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The orbital angular momentum (OAM) multiplexing controversy: OAM as a subset of MIMO | Recently the orbital angular momentum (OAM) multiplexing scheme has been proposed to increase without limit the channel capacity between a transmitter and a receiver node communicating in line of sight. A controversy arose about the far-field effectiveness of this method and about it being or not a subset of MIMO communication schemes. In this contribution we first illustrate that OAM multiplexing can be completely understood as line of sight MIMO, and hence that the technique cannot bring additional advantages in far field communications. Secondly, we show that it is possible to build similar line of sight near field MIMO systems based on lenses with similar or better performance than their OAM counterparts. |
Self-Autonomous Wireless Sensor Nodes With Wind Energy Harvesting for Remote Sensing of Wind-Driven Wildfire Spread | The satellite-based remote sensing technique has been widely used in monitoring wildfire spread. There are two prominent drawbacks with this approach of using satellites located in space: (1) very low sampling rate (temporal resolution problem) and (2) lack of accuracy (spatial and spectral resolution problem). To address these challenges, a wireless sensor network deployed at ground level with high-fidelity and low-altitude atmospheric sensing for wind speed of local wildfire spread has been used. An indirect approach in sensing wind speed has been proposed in this paper as an alternative to the bulky conventional wind anemometer to save cost and space. The wind speed is sensed by measuring the equivalent electrical output voltage of the wind turbine generator (WTG). The percentage error in the wind speed measurement using the proposed indirect method is measured to be well within the ±4% limit with respect to wind anemometer accuracy. The same WTG also functions as a wind energy harvesting (WEH) system to convert the available wind energy into electrical energy to sustain the operation of the wireless sensor node. The experimental results show that the designed WEH system is able to harvest an average electrical power of 7.7 mW at an average wind speed of 3.62 m/s for powering the operation of the wireless sensor node that consumes 3.5 mW for predicting the wildfire spread. Based on the sensed wind speed information, the fire control management system determines the spreading condition of the wildfire, and an adequate fire suppression action can be performed by the fire-fighting experts. |
Compartmentalization of S-RNase and HT-B degradation in self-incompatible Nicotiana | Pollen–pistil interactions are crucial for controlling plant mating. For example, S-RNase-based self-incompatibility prevents inbreeding in diverse angiosperm species. S-RNases are thought to function as specific cytotoxins that inhibit pollen that has an S-haplotype that matches one of those in the pistil. Thus, pollen and pistil factors interact to prevent mating between closely related individuals. Other pistil factors, such as HT-B, 4936-factor and the 120 kDa glycoprotein, are also required for pollen rejection but do not contribute to S-haplotype-specificity per se. Here we show that S-RNase is taken up and sorted to a vacuolar compartment in the pollen tubes. Antibodies to the 120 kDa glycoprotein label the compartment membrane. When the pistil does not express HT-B or 4936-factor, S-RNase remains sequestered, unable to cause rejection. Similarly, in wild-type pistils, compatible pollen tubes degrade HT-B and sequester S-RNase. We suggest that S-RNase trafficking and the stability of HT-B are central to S-specific pollen rejection. |
Effectiveness, safety, and acceptability of cryotherapy by midwives for cervical intraepithelial neoplasia in Maharashtra, India. | OBJECTIVE
To evaluate the effectiveness, safety, and acceptability of cryotherapy for cervical intraepithelial neoplasia (CIN) when provided by trained midwives in rural India.
METHOD
Women with colposcopic findings of CIN lesions suitable for ablative treatment received cryotherapy from trained midwives before the biopsy results were known. Cure rates, adverse effects, and complications were assessed and factors influencing cure rates were evaluated by chi(2) tests. Cure was defined as no clinical or histologic evidence of CIN lesions 6 or more months after treatment.
RESULTS
Of 1068 women treated with cryotherapy, 728 had histologically proven CIN in their pretreatment biopsy specimens; of the 574 reporting for follow-up, 538 (93.7%) were cured (95% confidence interval [CI], 92.1%-96.3%). Cure rates were 96.4% (95% CI, 94.6%-98.1%) for CIN 1 and 82.1% (95% CI, 74.7%-89.4%) for CIN 2 and CIN 3 lesions combined. Minor adverse effects were documented in 5.2% of the women.
CONCLUSION
Cryotherapy provided by midwives was found to be safe, effective, and acceptable by the women. |
Use and misuse of serum troponin assays in pediatric practice. | Cardiac troponin (cTn) is instrumental in screening and diagnosing myocardial ischemia in adults. However, the role of cTn screening in the pediatric population is less clear. The purpose of this study was to evaluate the current clinical practice, diagnostic and prognostic value, and resource utilization associated with cTn assays in the pediatric population. A multicenter, retrospective review of all cTn assays performed on patients aged ≤18 years from January 2003 to December 2010 in the Intermountain Healthcare system was conducted. Data collected included patient demographics, location, presenting symptoms, provisional and discharge diagnoses, additional tests, clinical outcomes (hospitalization days, ventilation, and death), and patient charges. During the study period, cTn assays were performed on 3,497 pediatric patients. The most common presenting diagnoses were chest pain (40%), trauma (11%), and poisoning or drug overdose (9%). Irrespective of diagnosis, elevated cTn was associated with an increased rate of hospitalization, ventilation, and death. Overall, 12% of patients had elevated cTn. Of the patients with chest pain, 4% had elevated cTn, 53% of whom were diagnosed with myopericarditis. In the myopericarditis group, 66% presented with fever, and 98% had abnormal electrocardiographic findings. For patients presenting with chest pain, approximately $162,000 was spent per positive result. In conclusion, cTn screening has strong prognostic value in pediatric patients, even in noncardiac diagnoses such as trauma or drug overdose. However, cTn screening in pediatric patients with chest pain provides minimal benefits and is associated with increased resource utilization, unless patients have constitutional symptoms, such as fever and/or electrocardiographic abnormalities. |
Rule Based Part of Speech Tagging of Sindhi Language | Part of Speech (POS) tagging is a process of assigning correct syntactic categories to each word in the text. Tag set and word disambiguation rules are fundamental parts of any POS tagger. No work has hitherto been published of tag set in Sindhi language. The Sindhi lexicon for computational processing is also not available. In this study, the tag set for Sindhi POS, lexicon and word disambiguation rules are designed and developed. The Sindhi corpus is collected from a comprehensive Sindhi Dictionary. The corpus is based on the most recent available vocabulary used by local people. In this paper, preliminary achievements of rule based Sindhi Part of Speech (SPOS) tagger are presented. Tagging and tokenization algorithms are also designed for the implementation of SPOS. The outputs of SPOS are verified by Sindhi linguist. The development of SPOS tagger may have an important milestone towards computational Sindhi language processing. |
Treatment of cutout of a lag screw of a dynamic hip screw in an intertrochanteric fracture | Sixteen consecutive patients with cutout of a lag screw of a dynamic hip screw fixation in an intertrochanteric fracture were treated with reinsertion of a lag screw, bone cement supplementation in the neck-trochanter, and subtrochanteric valgus osteotomy. Postoperatively, patients were permitted to ambulate with protected weight-bearing. Fourteen patients were followed-up for at least 1 year (median 2 years; range 1–3 years), and all had a solid union. The union period took a median of 5 months, with a range of 3–7 months. Usually, union of an intertrochanteric fracture was faster than that of subtrochanteric osteotomy (P < 0.01). There were no complications of wound infection, loss of reduction, cutout of a lag screw, or osteonecrosis of the femoral head. From clinical and theoretical considerations, we conclude that despite cutout of a lag screw of a dynamic hip screw fixation being difficult to treat, out technique still can provide an excellent outcome. Therefore, we strongly recommend its wide use. |
A model of prehospital trauma training for lay persons devised in Africa. | OBJECTIVES
Few low income countries have emergency medical services to provide prehospital medical care and transport to road traffic crash casualties. In Ghana most roadway casualties receive care and transport to the hospital from taxi, bus, or truck drivers. This study reports the methods used to devise a model for prehospital trauma training for commercial drivers in Ghana.
METHODS
Over 300 commercial drivers attended a first aid and rescue course designed specifically for roadway trauma and geared to a low education level. The training programme has been evaluated twice at one and two year intervals by interviewing both trained and untrained drivers with regard to their experiences with injured persons. In conjunction with a review of prehospital care literature, lessons learnt from the evaluations were used in the revision of the training model.
RESULTS
Control of external haemorrhage was quickly learnt and used appropriately by the drivers. Areas identified needing emphasis in future trainings included consistent use of universal precautions and protection of airways in unconscious persons using the recovery position.
CONCLUSION
In low income countries, prehospital trauma care for roadway casualties can be improved by training laypersons already involved in prehospital transport and care. Training should be locally devised, evidence based, educationally appropriate, and focus on practical demonstrations. |
Deep Temporal Architecture for Audiovisual Speech Recognition | The Audiovisual Speech Recognition (AVSR) is one of the applications of multimodal machine learning related to speech recognition, lipreading systems and video classification. In recent and related work, increasing efforts are made in Deep Neural Network (DNN) for AVSR, moreover some DNN models including Multimodal Deep Autoencoder, Multimodal Deep Belief Network and Multimodal Deep Boltzmann Machine perform well in experiments owing to the better generalization and nonlinear transformation. However, these DNN models have several disadvantages: (1) They mainly deal with modal fusion while ignoring temporal fusion. (2) Traditional methods fail to consider the connection among frames in the modal fusion. (3) These models aren’t end-to-end structure. We propose a deep temporal architecture, which has not only classical modal fusion, but temporal modal fusion and temporal fusion. Furthermore, the overfitting and learning with small size samples in the AVSR are also studied, so that we propose a set of useful training strategies. The experiments show the superiority of our model and necessity of the training strategies in three datasets: AVLetters, AVLetters2, AVDigits. In the end, we conclude the work. |
Online Deduplication for Databases | dbDedup is a similarity-based deduplication scheme for on-line database management systems (DBMSs). Beyond block-level compression of individual database pages or operation log (oplog) messages, as used in today's DBMSs, dbDedup uses byte-level delta encoding of individual records within the database to achieve greater savings. dbDedup's single-pass encoding method can be integrated into the storage and logging components of a DBMS to provide two benefits: (1) reduced size of data stored on disk beyond what traditional compression schemes provide, and (2) reduced amount of data transmitted over the network for replication services. To evaluate our work, we implemented dbDedup in a distributed NoSQL DBMS and analyzed its properties using four real datasets. Our results show that dbDedup achieves up to 37x reduction in the storage size and replication traffic of the database on its own and up to 61x reduction when paired with the DBMS's block-level compression. dbDedup provides both benefits with negligible effect on DBMS throughput or client latency (average and tail). |
Implementation of Real Time Bus Monitoring and Passenger Information System | In the daily operation of a bus system, the movement of vehicles is affected by uncertain conditions as the day progresses, such as traffic congestion, unexpected delays, and randomness in passenger demand, irregular vehicle dispatching times, and incidents. In a real-time setting, researchers have devoted significant effort to developing flexible control strategies, depending on the specific features of public transport systems. This paper focuses on the implementation of a Real Time Passenger Information (RTPI) system, by installing GPS devices on city buses. The Real Time Bus Monitoring and Passenger Information system is a standalone system designed to display the real-time location(s) of the buses in city. This research will enable the tracking devices to obtain GPS data of the bus locations, which it will then transfer it to centralized control unit and depict it by activating symbolic representation of buses in the approximate geographic positions on the route map. Specific software’s will be used to interface the data received to the map. The main Objectives of this research work are : 1. RTPIS rolling display on bus stops – expected time of arrival in real time. 2. Web based interface for control room to monitor buses in real time. 3. Mobile application for end user to find out bus schedules and RTPIS. |
Mobile Commerce: Framework, Applications and Networking Support | Advances in e-commerce have resulted in significant progress towards strategies, requirements, and development of e-commerce applications. However, nearly all e-commerce applications envisioned and developed so far assume fixed or stationary users with wired infrastructure. We envision many new e-commerce applications that will be possible and significantly benefit from emerging wireless and mobile networks. To allow designers, developers, and researchers to strategize and create mobile commerce applications, we propose a fourlevel integrated framework for mobile commerce. Since there are potentially an unlimited number of mobile commerce applications, we attempt to identify several important classes of applications such as mobile financial applications, mobile inventory management, proactive service management, product location and search, and wireless re-engineering. We discuss how to successfully define, architect, and implement the necessary hardware/software infrastructure in support of mobile commerce. Also, to make mobile commerce applications a reality, we address networking requirements, discuss support from wireless carriers, and present some open research problems. |
100 000 Frames/s 64 × 32 Single-Photon Detector Array for 2-D Imaging and 3-D Ranging | We report on the design and characterization of a multipurpose 64 × 32 CMOS single-photon avalanche diode (SPAD) array. The chip is fabricated in a high-voltage 0.35-μm CMOS technology and consists of 2048 pixels, each combining a very low noise (100 cps at 5-V excess bias) 30-μm SPAD, a prompt avalanche sensing circuit, and digital processing electronics. The array not only delivers two-dimensional intensity information through photon counting in either free-running (down to 10-μs integration time) or time-gated mode, but can also perform smart light demodulation with in-pixel background suppression. The latter feature enables phase-resolved imaging for extracting either three-dimensional depth-resolved images or decay lifetime maps, by measuring the phase shift between a modulated excitation light and the reflected photons. Pixel-level memories enable fully parallel processing and global-shutter readout, preventing motion artifacts (e.g., skew, wobble, motion blur) and partial exposure effects. The array is able to acquire very fast optical events at high frame-rate (up to 100 000 fps) and at single-photon level. Low-noise SPADs ensure high dynamic range (up to 110 dB at 100 fps) with peak photon detection efficiency of almost 50% at 410 nm. The SPAD imager provides different operating modes, thus, enabling both time-domain applications, like fluorescence lifetime imaging (FLIM) and fluorescence correlation spectroscopy, as well as frequency-domain FLIM and lock-in 3-D ranging for automotive vision and lidar. |
Malignancies in cases with screening-identified evidence of coeliac disease: a long-term population-based cohort study. | BACKGROUND AND AIMS
The association between diagnosed coeliac disease and malignancy has been established. The present study was conducted to determine whether previously unrecognised and thus untreated adults with screening-identified evidence of coeliac disease carry an increased risk of malignancies.
METHODS
A Finnish population-based adult-representative cohort of 8000 individuals was drawn in 1978-1980. Stored sera of the participants with no history of coeliac disease or any malignancy were tested for immunoglobulin A (IgA) class tissue transglutaminase antibodies (Eu-tTG) in 2001. Positive sera were further analysed by another tissue transglutaminase antibody test (Celikey tTG) and for endomysial antibodies (EMAs). Malignant diseases were extracted from the nationwide database and antibody-positive cases were compared with negative cases during a follow-up of nearly 20 years.
RESULTS
Altogether 565 of all the 6849 analysed serum samples drawn in 1978-80 were Eu-tTG positive. In further analyses, 202 (2.9%) of the participants were Celikey tTG positive and 73 (1.1%) were EMA positive. The overall risk of malignancy was not increased among antibody-positive cases in the follow-up of two decades; the age- and sex-adjusted relative risk was 0.91 (95% CI 0.60 to 1.37) for those who were Celikey tTG positive and 0.67 (95% CI 0.28 to 1.61) for those who were EMA positive.
CONCLUSIONS
The prognosis of adults with unrecognised coeliac disease with positive coeliac disease antibody status is good as regards the overall risk of malignancies. Thus, current diagnostic practice is sufficient and there is no need for earlier diagnosis of coeliac disease by mass screening on the basis of the findings of this study. |
Prefrontal cortical dysfunction in abstinent cocaine abusers. | The anterior cingulate cortex (ACC) and lateral prefrontal (LPFC) cortex are brain regions important to executive cognitive functions (ECF). We determined ACC and LPFC function in 23-day abstinent cocaine abusers using positron emission tomography (PET H(2)(15)O) during performance of a modified version of the Stroop Task. Cocaine abusers showed less activation than non-drug-using comparison subjects in the left ACC and the right LPFC and greater activation in the right ACC. Average amount of cocaine used per week was negatively correlated with activity in the rostral ACC and right LPFC. Disruption of ECF in substance abusers could interfere with attempts to stop drug use and undermine treatment. Since impairment in ECF may be a common feature of various neuropsychiatric disorders, these findings have applicability beyond the neurobiology of addiction. |
Limitations of the approximation capabilities of neural networks with one hidden layer | Let s/> 1 be an integer and W be the class of all functions having integrable partial derivatives on [0, 1] s. We are interested in the minimum number of neurons in a neural network with a single hidden layer required in order to provide a mean approximation order of a preassigned e > 0 to each function in W. We prove that this number cannot be O(e -s log(I/e)) if a spline-like localization is required. This cannot be improved even if one allows different neurons to evaluate different activation functions, even depending upon the target function. Nevertheless, for any 6 > 0, a network with O(c -s-6) neurons can be constructed to provide this order of approximation, with localization. Analogous results are also valid for other L p n o r m s . |
Lovastatin effects on bone mineral density in postmenopausal women with type 2 diabetes mellitus | The objective of this study was to examine the effects of lovastatin on bone mineral density (BMD) of postmenopausal women with type 2 diabetes mellitus (DM). The study was an open-label clinical trial conducted from March 2002 to November 2003. Fifty-five postmenopausal women age 54–67 years with type 2 DM were allocated to lovastatin-treated and control (without lovastatin) groups based on low-density lipoprotein cholesterol (LDL-C) >130 or ≤130 mg/dl. The first group received lovastatin (20 mg daily titrated every 3 months to keep LDL-C less than 130 mg/dl) for a total of 18 months. The second group received their own diabetic regimen without statin. The BMD of the lumbar spine (L1-L4), femoral neck, Wards triangle, trochanter and total hip was measured by dual-energy X-ray absorptiometry at baseline and after 18 months. In the 28 women treated with lovastatin, the BMD increased in lumbar spine (from 0.946 (0.122) to 0.978 (0.135) g/cm2, p<0.01) and Ward’s triangle (from 0.685 (0.123) to 0.780 (0.186) g/cm2, p<0.01). In the 27 women not treated with statin, the changes in BMD at all bone sites were not statistically significant. BMD was higher in femoral neck (1.2% vs. −2.7%, p<0.05), Ward’s triangle (13.9% vs. 3.3%, p<0.05), trochanter (−0.1% vs. −2.9%, p<0.05), total hip (1.2% vs. −1.4%, p<0.05) and lumbar spine (3.4% vs. 1.2%, p>0.05) at the end of the study. Treatment with lovastatin may prevent bone loss in postmenopausal women with type 2 DM. |
Fast and Space-Efficient Entity Linking for Queries | Entity linking deals with identifying entities from a knowledge base in a given piece of text and has become a fundamental building block for web search engines, enabling numerous downstream improvements from better document ranking to enhanced search results pages. A key problem in the context of web search queries is that this process needs to run under severe time constraints as it has to be performed before any actual retrieval takes place, typically within milliseconds.
In this paper we propose a probabilistic model that leverages user-generated information on the web to link queries to entities in a knowledge base. There are three key ingredients that make the algorithm fast and space-efficient. First, the linking process ignores any dependencies between the different entity candidates, which allows for a O(k2) implementation in the number of query terms. Second, we leverage hashing and compression techniques to reduce the memory footprint. Finally, to equip the algorithm with contextual knowledge without sacrificing speed, we factor the distance between distributional semantics of the query words and entities into the model.
We show that our solution significantly outperforms several state-of-the-art baselines by more than 14% while being able to process queries in sub-millisecond times---at least two orders of magnitude faster than existing systems. |
Protection: principles and practice | The protection mechanisms of computer systems control the access to objects, especially information objects. The range of responsibilities of these mechanisms includes at one extreme completely isolating executing programs from each other, and at the other extreme permitting complete cooperation and shared access among executing programs. Within this range one can identify at least seven levels at which protection mechanisms can be conceived as being required, each level being more difficult than its predecessor to implement:
1. No sharing at all (complete isolation).
2. Sharing copies of programs or data files.
3. Sharing originals of programs or data files.
4. Sharing programming systems or subsystems.
5. Permitting the cooperation of mutually suspicious subsystems---e.g., as with debugging or proprietary subsystems.
6. Providing "memoryless" subsystems---i.e., systems which, having performed their tasks, are guaranteed to have kept no secret record of the task performed (an income-tax computing service, for example, must be allowed to keep billing information on its use by customers but not to store information secretly on customers' incomes).
7. Providing "certified" subsystems---i.e., those whose correctness has been completely validated and is guaranteed a priori. |
Accuracy of diagnostic tests read with and without clinical information: a systematic review. | CONTEXT
Although it is common practice to read tests with clinical information, whether this improves or decreases the accuracy of test reading is uncertain.
OBJECTIVE
To determine whether diagnostic tests are more accurate when read with clinical information or without it.
DATA SOURCES
MEDLINE search (1966-December 2003) extended by search of reference lists and articles citing the articles retrieved (Web of Science, 1985-December 2003).
STUDY SELECTION
All articles comparing the accuracy of tests read twice by the same readers, once without and once with clinical information, but otherwise under identical conditions. Only articles that reported sensitivity and specificity or receiver operating characteristic (ROC) curves were included.
DATA EXTRACTION
Data were extracted by one author and reviewed independently by the other. When the data were difficult to interpret, differences were resolved by discussion.
DATA SYNTHESIS
Sixteen articles met the inclusion criteria. Eleven articles compared areas under ROC curves for tests read with and without clinical information, and 5 compared only sensitivity and specificity. Ten articles used actual clinical information; 6 used constructed clinical information that was plausible. Overall, clinical information improved test reading accuracy although the effect was smaller in the articles using actual clinical information when compared with those using constructed clinical information. There were no instances in which clinical information resulted in significant reduction in test reading accuracy. In some instances, improved test reading accuracy came from improved sensitivity without loss of specificity.
CONCLUSIONS
At least for the tests examined, the common practice of reading diagnostic tests with clinical information seems justified. Future studies should be designed to investigate the best way of providing clinical information. These studies should also give an estimate of the accuracy of clinical information used, display ROC curves with identified data points, and include a wider range of diagnostic tests. |
Social Exchange in Organizations : Perceived Organizational Support , Leader-Member Exchange , and Employee Reciprocity | Social exchange (P. Blau, 1964) and the norm of reciprocity (A. W. Gouldner, 1960) have been used to explain the relationship of perceived organizational support and leader-member exchange with employee attitudes and behavior. Recent empirical research suggests that individuals engage in different reciprocation efforts depending on the exchange partner (e.g., B. L. McNeely & B. M. Meglino, 1994). The purpose of the present study was to further investigate these relationships by examining the relative contribution of indicators of employee-organization exchange and subordinate-supervisor exchange. Structural equation modeling was used to compare nested models. Results indicate that perceived organizational support is associated with organizational commitment, whereas leader-member exchange is associated with citizenship and in-role behavior. |
Adaptive-Critic-Based Robust Trajectory Tracking of Uncertain Dynamics and Its Application to a Spring–Mass–Damper System | In this paper, the robust trajectory tracking design of uncertain nonlinear systems is investigated by virtue of a self-learning optimal control formulation. The primary novelty lies in that an effective learning based robust tracking control strategy is developed for nonlinear systems under a general uncertain environment. The augmented system construction is performed by combining the tracking error with the reference trajectory. Then, an improved adaptive critic technique, which does not depend on the initial stabilizing controller, is employed to solve the Hamilton–Jacobi–Bellman (HJB) equation with respect to the nominal augmented system. Using the obtained control law, the closed-loop form of the augmented system is built with stability proof. Moreover, the robust trajectory tracking performance is guaranteed via Lyapunov approach in theory and then through simulation demonstration, where an application to a practical spring–mass–damper system is included. |
Large-scale joint map matching of GPS traces | We present a robust method for solving the map matching problem exploiting massive GPS trace data. Map matching is the problem of determining the path of a user on a map from a sequence of GPS positions of that user --- what we call a trajectory. Commonly obtained from GPS devices, such trajectory data is often sparse and noisy. As a result, the accuracy of map matching is limited due to ambiguities in the possible routes consistent with trajectory samples. Our approach is based on the observation that many regularity patterns exist among common trajectories of human beings or vehicles as they normally move around. Among all possible connected k-segments on the road network (i.e., consecutive edges along the network whose total length is approximately k units), a typical trajectory collection only utilizes a small fraction. This motivates our data-driven map matching method, which optimizes the projected paths of the input trajectories so that the number of the k-segments being used is minimized. We present a formulation that admits efficient computation via alternating optimization. Furthermore, we have created a benchmark for evaluating the performance of our algorithm and others alike. Experimental results demonstrate that the proposed approach is superior to state-of-art single trajectory map matching techniques. Moreover, we also show that the extracted popular k-segments can be used to process trajectories that are not present in the original trajectory set. This leads to a map matching algorithm that is as efficient as existing single trajectory map matching algorithms, but with much improved map matching accuracy. |
IMAGE AUTHENTICATION AND RECOVERY USING WAVELET-BASED DUAL WATERMARKING | In this paper a novel watermarking scheme for image authentication and recovery is presented. The algorithm can detect modified regions in images and is able to recover a good approximation of the original content of the tampered regions. For this purpose, two different watermarks have been used: a semi-fragile watermark for image authentication and a robust watermark for image recovery, both embedded in the Discrete Wavelet Transform domain. The proposed method achieves good image quality with mean Peak Signal-to-Noise Ratio values of the watermarked images of 42 dB and identifies image tampering of up to 20% of the original image. |
Hyponatraemia in adults with community-acquired bacterial meningitis. | BACKGROUND
Hyponatraemia in adults with bacterial meningitis has been described as a common complication, but its true prevalence and clinical importance are unknown.
AIM
To investigate the prevalence, clinical characteristics and consequences of hyponatraemia in bacterial meningitis in adults.
DESIGN
Nationwide observational cohort study.
METHODS
We prospectively assessed the prevalence and clinical characteristics of hyponatraemia among 696 adults with community-acquired bacterial meningitis. Symptoms and signs on admission, blood and CSF test results, radiological examinations and complications during admission were recorded.
RESULTS
Sodium levels were determined at admission in 685/696 episodes of bacterial meningitis (98%). Hyponatraemia (<135 mmol/l) was seen in 208/685 (30%) and was classified as severe (<130 mmol/l) in 38 (6%). Hyponatraemia developed during admission in an additional 53 episodes. Hyponatraemia was not associated with an increase in symptoms, with complications or with unfavourable outcome. Treatment for hyponatraemia was initiated in 16% of episodes, but did not influence its duration.
DISCUSSION
Hyponatraemia appears both common and benign in adults with bacterial meningitis. In cases of severe hyponatraemia, we suggest the use of fluid maintenance therapy. |
Security issues in SCADA networks | The increasing interconnectivity of SCADA (Supervisory Control and Data Acquisition) networks has exposed them to a wide range of network security problems. This paper provides an overview of all the crucial research issues that are involved in strengthening the cyber security of SCADA networks. The paper describes the general architecture of SCADA networks and the properties of some of the commonly used SCADA communication protocols. The general security threats and vulnerabilities in these networks are discussed followed by a survey of the research challenges facing SCADA networks. The paper discusses the ongoing work in several SCADA security areas such as improving access control, firewalls and intrusion detection systems, SCADA protocol analyses, cryptography and key management, device and operating system security. Many trade and research organizations are involved in trying to standardize SCADA security technologies. The paper concludes with an overview of these standardization efforts. a 2006 Elsevier Ltd. All rights reserved. Modern industrial facilities, such as oil refineries, chemical factories, electric power generation plants, and manufacturing facilities are large, distributed complexes. Plant operators must continuously monitor and control many different sections of the plant to ensure its proper operation. The development of networking technology has made this remote command and control feasible. The earliest control networks were simple point-to-point networks connecting a monitoring or command device to a remote sensor or actuator. These have since evolved into complex networks that support communication between a central control unit and multiple remote units on a common communication bus. The nodes on these networks are usually special purpose embedded computing devices such as sensors, actuators, and PLCs. These industrial command and control networks are commonly called SCADA (Supervisory Control and Data Acquisition) networks. In today’s competitive markets, it is essential for industries to modernize their digital SCADA networks to reduce costs and increase efficiency. Many of the current SCADA networks * Corresponding author. E-mail addresses: [email protected] (V.M. Igure), sal4t@virginia 0167-4048/$ – see front matter a 2006 Elsevier Ltd. All rights reserve doi:10.1016/j.cose.2006.03.001 are also connected to the company’s corporate network and to the Internet. This improved connectivity can help to optimize manufacturing and distribution processes, but it also exposes the safety-critical industrial network to the myriad security problems of the Internet. If processes are monitored and controlled by devices connected over the SCADA network then a malicious attack over the SCADA network has the potential to cause significant damage to the plant. Apart from causing physical and economic loss to the company, an attack against a SCADA network might also adversely affect the environment and endanger public safety. Therefore, security of SCADA networks has become a prime concern. 1. SCADA network architecture A SCADA network provides an interconnection for field devices on the plant floor. These field devices, such as sensors and actuators, are monitored and controlled over the SCADA network by either a PC or a Programmable Logic Controller .edu (S.A. Laughter), [email protected] (R.D. Williams). d. c o m p u t e r s & s e c u r i t y 2 5 ( 2 0 0 6 ) 4 9 8 – 5 0 6 499 (PLC). In many cases, the plants also have a dedicated control center to screen the entire plant. The control center is usually located in a separate physical part of the factory and typically has advanced computation and communication facilities. Modern control centers have data servers, Human–Machine Interface (HMI) stations and other servers to aid the operators in the overall management of the factory network. This SCADA network is usually connected to the outside corporate network and/or the Internet through specialized gateways (Sauter and Schwaiger, 2002; Schwaiger and Treytl, 2003). The gateways provide the interface between IP-based networks on the outside and the fieldbus protocol-based SCADA networks on the factory floor. The gateway provides the protocol conversion mechanisms to enable communication between the two different networks. It also provides cache mechanisms for data objects that are exchanged between the networks in order to improve the gateway performance (Sauter and Schwaiger, 2002). A typical example of SCADA network is shown in Fig. 1. Apart from performance considerations, the design requirements for a SCADA network are also shaped by the operating conditions of the network (Decotignie, 1996). These conditions influence the topology of the network and the network protocol. The resulting SCADA networks have certain unique characteristics. For example, most of the terminal devices in fieldbus networks are special purpose embedded computing systems with limited computing capability and functionality. Unlike highly populated corporate office networks, many utility industry applications of SCADA networks, such as electric power distribution, are usually sparse, yet geographically extensive. Similarly, the physical conditions of a factory floor are vastly different from that of a corporate office environment. Both the large utility and factory floor networks are often subjected to wide variations in temperature, electro-magnetic radiation, and even simple accumulation of large quantities of dust. All of these conditions increase the noise on the network and also reduce the lifetime of the wires. The specifications for the physical layer of the network must be able to withstand such harsh conditions and manage the noise on the network. Typical communications on a SCADA network include control messages exchanged between master and slave devices. A master device is one which can control the operation of another device. A PC or a PLC is an example of a master device. A slave device is usually a simple sensor or actuator which can send messages to the command device and carry out actions at the command of a master device. However, the network protocol should also provide features for communication between fieldbus devices that want to communicate as peers. To accommodate these requirements, protocols such as PROFIBUS have a hybrid communication model, which includes a peer-to-peer communication model between master devices and a client–server communication model between masters and slaves. The communication between devices can also be asymmetric (Carlson, 2002; Risley et al., 2003). For example, messages sent from the slave to the master are typically much larger than the messages sent from the master to the slave. Some devices may also communicate only through alarms and status messages. Since many devices share a common bus, the protocol must have features for assigning priorities to messages. This helps distinguish between critical and non-critical messages. For example, an alarm message about a possible safety violation should take precedence over a regular data update message. SCADA network protocols must also provide some degree of delivery assurance and stability. Many factory processes require realtime communication between field devices. The network protocol should have features that not only ensure that the Fig. 1 – Typical SCADA network architecture. c o m p u t e r s & s e c u r i t y 2 5 ( 2 0 0 6 ) 4 9 8 – 5 0 6 500 critical messages are delivered but that they are delivered within the time constraints. |
Graph-based Knowledge Representation - Computational Foundations of Conceptual Graphs | Spend your few moment to read a book even only few pages. Reading book is not obligation and force for everybody. When you don't want to read, you can get punishment from the publisher. Read a book becomes a choice of your different characteristics. Many people with reading habit will always be enjoyable to read, or on the contrary. For some reasons, this graph based knowledge representation computational foundations of conceptual graphs advanced information and knowledge processing tends to be the representative book in this website. |
Structured Attentions for Visual Question Answering | Visual attention, which assigns weights to image regions according to their relevance to a question, is considered as an indispensable part by most Visual Question Answering models. Although the questions may involve complex rela- tions among multiple regions, few attention models can ef- fectively encode such cross-region relations. In this paper, we demonstrate the importance of encoding such relations by showing the limited effective receptive field of ResNet on two datasets, and propose to model the visual attention as a multivariate distribution over a grid-structured Con- ditional Random Field on image regions. We demonstrate how to convert the iterative inference algorithms, Mean Field and Loopy Belief Propagation, as recurrent layers of an end-to-end neural network. We empirically evalu- ated our model on 3 datasets, in which it surpasses the best baseline model of the newly released CLEVR dataset [13] by 9.5%, and the best published model on the VQA dataset [3] by 1.25%. Source code is available at https://github.com/zhuchen03/vqa-sva. |
Design and control of a wearable hand exoskeleton with force-controllable and compact actuator modules | In this paper, a wearable hand exoskeleton with force-controllable and compact actuator modules is proposed. In order to apply force feedback accurately while allowing natural finger motions, the exoskeleton linkage structure with three degrees of freedom (DOFs) was designed, which was inspired by the muscular skeletal structure of the finger. As an actuating system, a series elastic actuator (SEA) mechanism, which consisted of a small linear motor, a manually designed motor driver, a spring and potentiometers, was applied. The friction of the motor was identified and compensated for obtaining a linearized model of the actuating system. Using a LQ (linear quadratic) tuned PD (proportional and derivative) controller and a disturbance observer (DOB), the proposed actuator module could generate the desired force accurately with actual finger movements. By integrating together the proposed exoskeleton structure, actuator modules and control algorithms, a wearable hand exoskeleton with force-controllable and compact actuator modules was developed to deliver accurate force to the fingertips for flexion/extension motions. |
A Model-Based Method for Remaining Useful Life Prediction of Machinery | Remaining useful life (RUL) prediction allows for predictive maintenance of machinery, thus reducing costly unscheduled maintenance. Therefore, RUL prediction of machinery appears to be a hot issue attracting more and more attention as well as being of great challenge. This paper proposes a model-based method for predicting RUL of machinery. The method includes two modules, i.e., indicator construction and RUL prediction. In the first module, a new health indicator named weighted minimum quantization error is constructed, which fuses mutual information from multiple features and properly correlates to the degradation processes of machinery. In the second module, model parameters are initialized using the maximum-likelihood estimation algorithm and RUL is predicted using a particle filtering-based algorithm. The proposed method is demonstrated using vibration signals from accelerated degradation tests of rolling element bearings. The prediction result identifies the effectiveness of the proposed method in predicting RUL of machinery. |
Practice variation in neuroimaging to evaluate dizziness in the ED. | BACKGROUND
The appropriate role of neuroimaging to evaluate emergency department (ED) patients with dizziness is not established by guidelines or evidence.
METHODS
We identified all adults with a triage complaint of dizziness who were evaluated at 20 EDs of a large Northern California integrated health care program in 2008. Using comprehensive medical records, we captured all head computed tomographies (CTs) or brain magnetic resonance images (MRIs) completed at presentation or within 2 days and all stroke diagnoses within 1 week. We assessed variation in neuroimaging use by site using a random-effects logistic model to account for differences in patient- (demographic and vascular risk factors) and site-level factors (volume, % patients with dizziness, and % patients with dizziness admitted) and linear regression to assess the relationship between neuroimaging rates and stroke diagnosis rates by site.
RESULTS
Of 378 992 patients seen in 2008, 20 795 (5.5%) had at least one ED visit for dizziness. Overall, 5585 patients (26.9%) had a head CT and 652 (3.1%) had a brain MRI. Between 21.8% and 32.8% of ED patients with dizziness at each site had a head CT (P<.001). For brain MRI, the range was 0.8% to 6.2%-a nearly 8-fold variation (P<.001) that persisted after adjustment for patient- and site-level factors. Higher neuroimaging rates did not translate into higher stroke diagnoses rates, with 0.7% to 2.5% of patients with dizziness diagnosed with stroke by site.
CONCLUSION
The use of neuroimaging for ED patients with dizziness varies substantially without an associated improvement in stroke diagnosis, which is identified only rarely. |
Short- and long-term COX-2 inhibition reverses endothelial dysfunction in patients with hypertension. | Hypertension is associated with endothelial dysfunction that is attributable to oxidative stress and a proinflammatory state. Under these conditions, enhanced expression of cyclooxygenase-2 might lead to increased production of vasoconstrictor prostanoids and reactive oxygen species that reduce the bioavailability of endothelium-derived nitric oxide. To investigate the contribution of cyclooxygenase-2 activity to endothelial dysfunction in human hypertension, we evaluated brachial artery vasodilator function by ultrasound in 29 hypertensive patients before and after treatment with the selective cyclooxygenase-2 inhibitor celecoxib or placebo in a randomized, double-blind study. Brachial artery flow-mediated dilation improved from a baseline of 7.9+/-4.5% to 9.9+/-5.1% (P=0.005) 3 hours after the first dose and to 10.1+/-6.1% (P=0.006) after 1 week of treatment with celecoxib. In contrast, placebo treatment had no significant effect on flow-mediated dilation (8.1+/-4.4%, 8.3+/-3.5%, and 8.0+/-3.2%, respectively). Neither treatment altered nitroglycerin-mediated dilation, extent of reactive hyperemia, or baseline arterial diameter. Celecoxib treatment had no significant effect on the urinary concentrations of F2 isoprostane or thromboxane metabolites. However, urinary concentrations of the prostacyclin metabolite 2,3-dinor-6-ketoprostglandin F1alpha were significantly lower after 1 week of celecoxib treatment. Thus, cyclooxygenase-2 products contribute to endothelial dysfunction in hypertension, and treatment with a cyclooxygenase-2 inhibitor could have a beneficial effect in this setting. However, cyclooxygenase-2 inhibition also has an adverse effect on prostacyclin production that could promote thrombosis, and the net clinical consequences of improved endothelial function versus loss of prostacyclin merits further investigation. |
Algorithm engineering for a quantum annealing platform | Recent advances bring within reach the viability of solving combinatorial problems using a quantum annealing algorithm implemented on a purpose-built platform that exploits quantum properties. However, the question of how to tune the algorithm for most effective use in this framework is not well understood. In this paper we describe some operational parameters that drive performance, discuss approaches for mitigating sources of error, and present experimental results from a D-Wave Two quantum annealing processor. |
The Spanish version of the Insomnia Severity Index: a confirmatory factor analysis. | OBJECTIVE
To examine the psychometric properties of the Spanish version of the Insomnia Severity Index (ISI) and to determine its factor structure with confirmatory factor analysis (CFA).
METHODS
Self-reported information was collected from a sample of 500 adults (mean age 39.13 [standard deviation 15.85]years) drawn from a population of medical students and their social networks. Together with the ISI, a measure of the subjective severity of insomnia, subjects completed the Pittsburg Sleep Quality Index, the Epworth Sleepiness Scale, and the Profile of Mood States to study concurrent validity of the ISI. CFA was used to test alternative models to ascertain the factorial structure of the ISI.
RESULTS
The Spanish version of the ISI showed adequate indices of internal consistency (Cronbach's α=0.82). CFA showed that a three-factor structure provided a better fit to the data than one-factor and two-factor structures. The ISI was significantly correlated with poor sleep quality, fatigue, anxiety, and depression, and discriminated between good and poor sleepers.
CONCLUSIONS
The ISI is a reliable and valid instrument to assess the subjective severity of insomnia in Spanish-speaking populations. Its three-factor structure (i.e., night-time sleep difficulties, sleep dissatisfaction and daytime impact of insomnia) makes it a psychometrically robust and clinically useful measure. |
Learning Programs: A Hierarchical Bayesian Approach | We are interested in learning programs for multiple related tasks given only a few training examples per task. Since the program for a single task is underdetermined by its data, we introduce a nonparametric hierarchical Bayesian prior over programs which shares statistical strength across multiple tasks. The key challenge is to parametrize this multi-task sharing. For this, we introduce a new representation of programs based on combinatory logic and provide an MCMC algorithm that can perform safe program transformations on this representation to reveal shared inter-program substructures. |
An Integrated Four-Port DC/DC Converter for Renewable Energy Applications | This paper proposes a novel converter topology that interfaces four power ports: two sources, one bidirectional storage port, and one isolated load port. The proposed four-port dc/dc converter is derived by simply adding two switches and two diodes to the traditional half-bridge topology. Zero-voltage switching is realized for all four main switches. Three of the four ports can be tightly regulated by adjusting their independent duty-cycle values, while the fourth port is left unregulated to maintain the power balance for the system. Circuit analysis and design considerations are presented; the dynamic modeling and close-loop design guidance are given as well. Experimental results verify the proposed topology and confirm its ability to achieve tight independent control over three power-processing paths. This topology promises significant savings in component count and losses for renewable energy power-harvesting systems. |
The health burden of breast hypertrophy. | Women seeking consultation for the surgical relief of symptoms associated with breast hypertrophy have been the focus of many studies. In contrast, little is known about those women with breast hypertrophy who do not seek symptomatic relief. The purpose of this study was to describe the health burden of breast hypertrophy by using a set of validated questionnaires and to compare women with breast hypertrophy who seek surgical treatment with those who do not. In addition, this latter group was compared with a group of control women without breast hypertrophy. Women seeking consultation for surgery were recruited from 14 plastic-surgery practices. Control subjects were recruited by advertisements in primary-care offices and newspapers. Women were asked to complete a self-report questionnaire that included the European Quality of Life (EuroQol) questionnaire, McGill Pain Questionnaire, Multidimensional Body Self Relations Questionnaire (MBSRQ), the Short Form-36 (SF-36) questionnaire, and questions regarding breast-related symptoms, comorbidities, and bra size. Descriptive statistics were compiled for three groups of women: (1) hypertrophy patients seeking surgical care, (2) hypertrophy control subjects (those whose reported bra-cup size was a D or larger), and (3) normal control subjects (those whose reported bra-cup size was an A, B, or C). The multiple linear regression method was used to compare the health burdens across groups while adjusting for other variables. Two hundred ninety-one women seeking surgical care and 195 control subjects were enrolled in the study. The 184 control subjects with bra-cup information available were further separated into 88 hypertrophy control subjects and 96 normal control subjects. In the control group, bra-cup size was correlated with health-burden measures, whereas in the surgical candidates, it was not. When scores were compared across the three groups, significant differences were found in all health-burden measures. The surgical candidates scored more poorly on the EuroQol utility, McGill pain rating index, MBSRQ appearance evaluation, physical component scale of the SF-36, and on breast symptoms than did the two control groups. In addition, the hypertrophy control subjects scored more poorly than the normal control subjects. With multiple linear regression analysis incorporating important potential confounders, the poorer scores in the surgical candidates remained statistically significant. It was concluded that breast hypertrophy in those seeking surgical care and those not seeking surgery has a significant impact on women's quality of life as measured by validated and widely used self-report instruments including the EuroQol, MBSRQ, McGill Pain Questionnaire, and the SF-36. Likewise, a new assessment instrument for breast-related symptoms also demonstrated greater symptomatology in women with breast hypertrophy. |
Smart Random Neural Network Controller for HVAC Using Cloud Computing Technology | Smart homes reduce human intervention in controlling the heating ventilation and air conditioning (HVAC) systems for maintaining a comfortable indoor environment. The embedded intelligence in the sensor nodes is limited due to the limited processing power and memory in the sensor node. Cloud computing has become increasingly popular due to its capability of providing computer utilities as internet services. In this study, a model for the intelligent controller by integrating internet of things (IoT) with cloud computing and web services is proposed. The wireless sensor nodes for monitoring the indoor environment and HVAC inlet air, and wireless base station for controlling the actuators of HVAC have been developed. The sensor nodes and base station communicate through RF transceivers at 915 MHz. Random neural network (RNN) models are used for estimating the number of occupants, and for estimating the predicted-mean-vote-based setpoints for controlling the heating, ventilation, and cooling of the building. Three test cases are studied (Case 1—Data storage and implementation of RNN models on the cloud, Case 2—RNN models implementation on base station, Case 3—Distributed implementation of RNN models on sensor nodes and base stations) for determining the best architecture in terms of power consumption. The results have shown that by embedding the intelligence in the base station and sensor nodes (i.e., Case 3), the power consumption of the intelligent controller was 4.4% less than Case 1 and 19.23% less than Case 2. |
Motivation Classification and Grade Prediction for MOOCs Learners | While MOOCs offer educational data on a new scale, many educators find great potential of the big data including detailed activity records of every learner. A learner's behavior such as if a learner will drop out from the course can be predicted. How to provide an effective, economical, and scalable method to detect cheating on tests such as surrogate exam-taker is a challenging problem. In this paper, we present a grade predicting method that uses student activity features to predict whether a learner may get a certification if he/she takes a test. The method consists of two-step classifications: motivation classification (MC) and grade classification (GC). The MC divides all learners into three groups including certification earning, video watching, and course sampling. The GC then predicts a certification earning learner may or may not obtain a certification. Our experiment shows that the proposed method can fit the classification model at a fine scale and it is possible to find a surrogate exam-taker. |
Influence of inclination error in sedimentary rocks on the Triassic and Jurassic apparent pole wander path for North America and implications for Cordilleran tectonics | [1] Because of paleomagnetic inclination error (I error) in sedimentary rocks, we argue that previous estimates of Triassic and Jurassic paleolatitudes of the North American craton have generally been too low, the record being derived mostly from sedimentary rocks. Using results from all major cratons, we construct a new composite apparent pole wander (APW) path for Triassic through Paleogene based on 69 paleopoles ranging in age from 243 to 43 Ma. The poles are from igneous rocks and certain sedimentary formations corrected for I error brought into North American coordinates using plate tectonic reconstructions. Key features of the new APW path are a 25° northward progression from 230 to 190 Ma to high latitudes (off northernmost Siberia) where the pole lingers until 160 Ma, a jump to the Aleutians followed by a hook in western Alaska by ∼145 Ma that leads to the 130–60 Ma stillstand, after which the pole moves to its present position. As an example of the application of this new path we use paleomagnetic results to determine that southern Wrangellia and Stikinia (W/S), the two most westerly terranes in the Canadian Cordillera, lay 630 to 1650 km farther south than at present relative to the craton during the Late Triassic and Early Jurassic. This is consistent with an exotic Tethyan origin as paleontological and mantle geochemical evidences imply. During the Late Triassic through Early Cretaceous, W/S moved northward more slowly than the craton, implying oblique sinistral net convergence over this 130 Myr interval. This was followed by dextral shear in latest Cretaceous through Eocene. |
Addition related arithmetic operations via controlled transport of charge | This work investigates the single electron tunneling (SET) technology-based computation of basic addition related arithmetic functions, e.g., addition and multiplication, via a novel computation paradigm, which we refer to as electron counting arithmetic, that is based on controlling the transport of discrete quantities of electrons within the SET circuit. First, assuming that the number of controllable electrons within the system is unrestricted, we prove that the addition of two n-bit operands can be computed with a depth-2 network composed out of 3n+1 circuit elements and that the multiplication of two n-bit operands can be computed with a depth-3 network composed out of 4n-1 circuit elements. Second, assuming that the number of controllable electrons cannot be higher than a given constant r determined by practical limitations, we prove that the addition of two n-bit operands can be computed with a depth-(n/r+3) network composed out of 3n+1+n/r circuit elements. Under the same restriction, we suggest methods to reduce the addition network depth in the order of logn/r and to perform n-bit multiplication in an O(logn/r) delay. Finally, we propose SET-based implementations for a set of basic electron counting building blocks and implement a number of circuits operating under the electron counting paradigm as follows: 4-bit digital to analog converter, 5-bit analog to digital converter, 4-bit adder, and 3-bit multiplier. All proposed implementations are verified by means of simulation. |
Segmenting and Tagging Text with Neural Networks | Shao, Y. 2018. Segmenting and Tagging Text with Neural Networks. Studia Linguistica Upsaliensia 21. 76 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-513-0340-6. Segmentation and tagging of text are important preprocessing steps for higher-level natural language processing tasks. In this thesis, we apply a sequence labelling framework based on neural networks to various segmentation and tagging tasks, including sentence segmentation, word segmentation, morpheme segmentation, joint word segmentation and part-of-speech tagging, and named entity transliteration. We apply a general neural CRF model to different tasks by designing specific tag sets. In addition, we explore effective ways of representing input characters, such as utilising concatenated n-grams and sub-character features, and use ensemble decoding to mitigate the effects of random parameter initialisation. The segmentation and tagging models are evaluated in a truly multilingual setup with more than 70 datasets. The experimental results indicate that the proposed neural CRF model is effective for segmentation and tagging in general as state-of-the-art accuracies are achieved on datasets in different languages, genres, and annotation schemes for various tasks. For word segmentation, we propose several typological factors to statistically characterise the difficulties posed by different languages and writing systems. Based on this analysis, we apply language-specific settings to the segmentation system for higher accuracy. Our system achieves substantially better results on languages that are more difficult to segment when compared to previous work. Moreover, we investigate conventionally adopted evaluation metrics for segmentation tasks. We propose that precision should be excluded and using recall alone is more adequate for sentence segmentation and word segmentation. The segmentation and tagging tools implemented along with this thesis are publicly available as experimental frameworks for future development as well as preprocessing tools for higher-level NLP tasks. |
'Leave me alone' lesions of the petrous apex. | PURPOSE
When troublesome MR imaging findings are noted in the petrous apex, the radiologist must determine if the area in question needs surgical therapy. Two nonsurgical entities, asymmetric fatty marrow and fluid-filled petrous air cells (trapped fluid), can be noted on conventional brain MR images and confused with pathologic lesions. Our observation that radiologists do not always confidently define the nonsurgical petrous apex lesions precipitated this investigation.
METHODS
Twenty-three patients with either asymmetric fatty marrow (six) or unilateral effusion in a pneumatized petrous apex (17) on MR images were studied. Eighteen patients underwent high-resolution temporal bone CT. For all patients, the medical charts were reviewed retrospectively and/or the surgical and clinical follow-up findings were reviewed with the referring physician.
RESULTS
In the patients with asymmetric fatty marrow, MR signal intensity followed fat on all sequences. The questioned apex in the patients with trapped fluid showed mixed MR signal characteristics (low to high T1 signal, high T2 signal). CT scans confirmed nonexpansile air-cell opacification.
CONCLUSION
Asymmetric fatty marrow in the petrous apex and petrous air-cell effusions have characteristic MR and CT features that facilitate their correct diagnosis. Effusions with intermediate or high T1 signal are most frequently confused with cholesterol granulomas. In those patients, long-term CT follow-up may be helpful to confirm their stability. |
Multirate Multimodal Video Captioning | Automatically describing videos with natural language is a crucial challenge of video understanding. Compared to images, videos have specific spatial-temporal structure and various modality information. In this paper, we propose a Multirate Multimodal Approach for video captioning. Considering that the speed of motion in videos varies constantly, we utilize a Multirate GRU to capture temporal structure of videos. It encodes video frames with different intervals and has a strong ability to deal with motion speed variance. As videos contain different modality cues, we design a particular multimodal fusion method. By incorporating visual, motion, and topic information together, we construct a well-designed video representation. Then the video representation is fed into a RNN-based language model for generating natural language descriptions. We evaluate our approach for video captioning on "Microsoft Research - Video to Text" (MSR-VTT), a large-scale video benchmark for video understanding. And our approach gets great performance on the 2nd MSR Video to Language Challenge. |
A 0.35μm CMOS sub-1V low-quiescent-current low-dropout regulator | A sub-1 V CMOS low-dropout (LDO) voltage regulator with 103 nA low-quiescent current is presented in this paper. The proposed LDO uses a digital error amplifier that can make the quiescent current lower than other LDOs with the traditional error amplifier. Besides, the LDO can be stable even without the output capacitor. With a 0.9 V power supply, the output voltage is designed as 0.5 V. The maximum output current of the LDO is 50 mA at an output of 0.5 V. The prototype of the LDO is fabricated with TSMC 0.35 mum CMOS processes. The active area without pads is only 240 mum times 400 mum. |
Studies on tissue culture of Chinese medicinal plant resources in Taiwan and their sustainable utilization | Medicinal plants are sources of important therapeutic aid for alleviating human ailments. With increasing realization of the health hazards and toxicity associated with the indiscriminate use of synthetic drugs and antibiotics, interest in the use of plants and plant-based drugs has revived throughout the world. However, a large number of medicinal plants remain to be investigated for their possible pharmacological value. Most of the pharmaceutical industry is highly dependent on wild populations for the supply of raw materials for extraction of medicinally important compounds. Due to a lack of proper cultivation practices, destruction of plant habitats, and the illegal and indiscriminate collection of plants from these habitats, many medicinal plants are severely threatened. Advanced biotechnological methods of culturing plant cells and tissues should provide new means of conserving and rapidly propagating valuable, rare, and endangered medicinal plants. This paper describes the work carried out at the Taiwan Agricultural Research Institute and Chaoyang University of Technology on in vitro propagation of some important medicinal plants. |
Vessel enhancing diffusion: A scale space representation of vessel structures | A method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffusion. The method performs better than most of the existing techniques in visualizing vessels with varying radii and in enhancing vessel appearance. A diameter study on phantom data shows that VED least affects the accuracy of diameter measurements. It is shown that using VED as a preprocessing step improves level set based segmentation of the cerebral vasculature, in particular segmentation of the smaller vessels of the vasculature. |
Receivables Management and Possible Use of Information Technologies | This paper is focused on receivables management and possibilities how to use available information technologies. The use of information technologies should make receivables management easier on one hand and on the other hand it makes the processes more efficient. Finally it decreases additional costs and losses connected with enforcing receivables when defaulting debts occur. The situation of use of information technologies is different if the subject is financial or nonfinancial institution. In the case of financial institution loans providing is core business and the processes and their technical support are more sophisticated than in the case of non-financial institutions whose loan providing as invoices is just a supplement to their core business activities. The paper shows use of information technologies in individual cases but it also emphasizes the use of general results for further decision making process. Results of receivables management are illustrated on the data of the Czech Republic. |
Entity resolution using inferred relationships and behavior | We present a method for entity resolution that infers relationships between observed identities and uses those relationships to aid in mapping identities to underlying entities. We also introduce the idea of using graphlets for entity resolution. Graphlets are collections of small graphs that can be used to characterize the “role” of a node in a graph. The idea is that graphlets can provide a richer set of features to characterize identities. We validate our method on standard author datasets, and we further evaluate our method using data collected from Twitter. We find that inferred relationships and graphlets are useful for entity resolution. |
Bioavailability of metronidazole in fasting and non-fasting healthy subjects and in patients with Crohn's disease | The possible influence of food intake on the bioavailability of metronidazole was examined in ten healthy volunteers by administration of a single dose of metronidazole on an empty stomach, and with a standardized breakfast. Food intake did not significantly alter the bioavailability of metronidazole. The interindividual variation in bioavailability appeared to be slight. In nine patients with Crohn's disease, the absorption of metronidazole appeared to be reduced and to be more variable than in healthy subjects. In both groups there was a clear relationship between the amount absorbed and dose/kg body weight. Thus, from the pharmacokinetic point of view, metronidazole can safely be given either with or between meals. The dose should be related to body weight. |
Docetaxel combined with vinorelbine: phase I results and new study designs. | This was a phase I dose-finding and pharmacokinetic study of vinorelbine (Navelbine) and docetaxel (Taxotere) as first-line chemotherapy for metastatic breast cancer. Vinorelbine dose, 20 or 22.5 mg/m2, on days 1 and 5, was followed on day 1 by docetaxel every 21 days, in doses increasing from 60 to 100 mg/m2. Two maximum tolerated doses were reached, the first at 75 mg/m2 of docetaxel and 22.5 mg/m2 of vinorelbine, and the second at 100 mg/m2 of docetaxel and 20 mg/m2 of vinorelbine. Symptomatic peripheral neuropathy was not observed. The recommended doses for phase II studies are 75 to 85 mg/m2 of docetaxel on day 1 and 20 mg/m2 of vinorelbine on days 1 and 5, every 3 weeks. The treatment regimen, which included 3-day corticosteroid prophylaxis, resulted in only mild fluid retention. Responses were seen at all dose levels, with an 80% overall response rate at the higher recommended dose; the overall response rate for patients at all dose levels was 66%. A high rate of response, including a complete response, was observed in patients with liver metastases. |
FEMINIST ATTITUDES AMONG AFRICAN AMERICAN WOMEN AND MEN | Research on the intersection of race and gender suggests that for African Americans, racial inequality is more salient than gender inequality. However theoretical perspectives on the multiplicative effects of status positions and "outsider within" models suggest that minority group membership can be a catalyst for the development of feminist attitudes. This article examines three issues central to feminism: (1) recognition and critique of gender inequality, (2) egalitarian gender roles, and (3) political activism for the rights of women. The authors found that support for feminist ideology was common for both African American women and men, although the level of support varied depending on the issue and by gender Factors predicting the endorsement of feminist ideology also varied depending on the issue and by gender The authors found partial support for the race saliency hypothesis, but there was also evidence of the multiplicative effects of status positions on African Americans feminist attitudes. Feminist Ideology | Race | African Americans | Gender Roles |
Impact of malaria morbidity on gross domestic product in Uganda | BACKGROUND
The burden of malaria is a key challenge to both human and economic development in malaria endemic countries. The impact of malaria can be categorized from three dimensions, namely: health, social and economic. The objective of this study was to estimate the impact of malaria morbidity on gross domestic product (GDP) of Uganda.
METHODS
The impact of malaria morbidity on GDP of Uganda was estimated using double-log econometric model. The 1997-2003 time series macro-data used in the analysis were for 28 quarters, i.e. 7 years times 4 quarters per year. It was obtained from national and international secondary sources.
RESULTS
The slope coefficient for Malaria Index (M) was -0.00767; which indicates that when malaria morbidity increases by one unit, while holding all other explanatory variables constant, per capita GDP decreases by US$0.00767 per year. In 2003 Uganda lost US$ 49,825,003 of GDP due to malaria morbidity. Dividing the total loss of US$49.8 million by a population of 25,827,000 yields a loss in GDP of US$1.93 per person in Uganda in 2003.
CONCLUSION
Malaria morbidity results in a substantive loss in GDP of Uganda. The high burden of malaria leads to decreased long-term economic growth, and works against poverty eradication efforts and socioeconomic development of the country. |
Genetic Improvement of Software: A Comprehensive Survey | Genetic improvement (GI) uses automated search to find improved versions of existing software. We present a comprehensive survey of this nascent field of research with a focus on the core papers in the area published between 1995 and 2015. We identified core publications including empirical studies, 96% of which use evolutionary algorithms (genetic programming in particular). Although we can trace the foundations of GI back to the origins of computer science itself, our analysis reveals a significant upsurge in activity since 2012. GI has resulted in dramatic performance improvements for a diverse set of properties such as execution time, energy and memory consumption, as well as results for fixing and extending existing system functionality. Moreover, we present examples of research work that lies on the boundary between GI and other areas, such as program transformation, approximate computing, and software repair, with the intention of encouraging further exchange of ideas between researchers in these fields. |
Exploring the link between reading fiction and empathy : Ruling out individual differences and examining outcomes | Readers of fiction tend to have better abilities of empathy and theory of mind (Mar et al., 2006). We present a study designed to replicate this finding, rule out one possible explanation, and extend the assessment of social outcomes. In order to rule out the role of personality, we first identified Openness as the most consistent correlate. This trait was then statistically controlled for, along with two other important individual differences: the tendency to be drawn into stories and gender. Even after accounting for these variables, fiction exposure still predicted performance on an empathy task. Extending these results, we also found that exposure to fiction was positively correlated with social support. Exposure to nonfiction, in contrast, was associated with loneliness, and negatively related to social support. |
Bullet-Proof Robust Real-Time Ball Tracking | This paper proposes a novel ball tracking approach for coping with difficult situations as occlusion and fast object movement, in the context of collective sports. In particular, in the context of soccer, the ball cannot be represented by the features which are commonly utilised in the state of the art, because of the high distortion of the ball in case of fast movement, and considering the small size of the ball (below 30 pixels), due to the distance of the static cameras with respect to football ground. In this work, we propose an elliptical model able to represent the distortion of the ball when is moving fast, which combines elliptical shape features with its current appearance, and the available information about the object dynamics. For ball tracking, we apply a two stage algorithm. At the first stage, a ball image matching method is applied, finding all the candidate regions for the position of the ball in the field. At the second stage, the detected regions are analysed in relation with the dynamics of the previously detected ball candidates, and their similarity with regions in the previous frames, rejecting candidates when the current region is more similar to previous no-ball regions in comparison to previous ball regions. If the ball is occluded by players or camouflaged by field lines, we apply a new additional method for recovering the position of the ball. The main contributions of our method are: the incorporation of the ball distortion to the ball model, and a new algorithm for the detection of the ball in occlusion situations. We have tested our approach in real benchmark sequences, facing complex challenges related to occlusion, low resolution, distortion due to speed, and illumination problems, with very competitive results. |
The Wisconsin Card Sorting Test: theoretical analysis and modeling in a neuronal network. | Neuropsychologists commonly use the Wisconsin Card Sorting Test as a test of the integrity of frontal lobe functions. However, an account of its range of validity and of the neuronal mechanisms involved is lacking. We analyze the test at 3 different levels. First, the different versions of the test are described, and the results obtained with normal subjects and brain-lesioned patients are reviewed. Second, a computational analysis is used to reveal what algorithms may pass the test, and to predict their respective performances. At this stage, 3 cognitive components are isolated that may critically contribute to performance: the ability to change the current rule when negative reward occurs, the capacity to memorize previously tested rules in order to avoid testing them twice, and the possibility of rejecting some rules a priori by reasoning. Third, a model neuronal network embodying these 3 components is described. The coding units are clusters of neurons organized in layers, or assemblies. A sensorimotor loop enables the network to sort the input cards according to several criteria (color, form, etc.). A higher-level assembly of rule-coding clusters codes for the currently tested rule, which shifts when negative reward is received. Internal testing of the possible rules, analogous to a reasoning process, also occurs, by means of an endogenous auto-evaluation loop. When lesioned, the model reproduces the behavior of frontal lobe patients. Plausible biological or molecular implementations are presented for several of its components. |
Fibroblast Growth Factor Receptor 2 (FGFR2) Mutation Related Syndromic Craniosynostosis | Craniosynostosis results from the premature fusion of cranial sutures, with an incidence of 1 in 2,100-2,500 live births. The majority of cases are non-syndromic and involve single suture fusion, whereas syndromic cases often involve complex multiple suture fusion. The fibroblast growth factor receptor 2 (FGFR2) gene is perhaps the most extensively studied gene that is mutated in various craniosynostotic syndromes including Crouzon, Apert, Pfeiffer, Antley-Bixler, Beare-Stevenson cutis gyrata, Jackson-Weiss, Bent Bone Dysplasia, and Seathre-Chotzen-like syndromes. The majority of these mutations are missense mutations that result in constitutive activation of the receptor and downstream molecular pathways. Treatment involves a multidisciplinary approach with ultimate surgical fixation of the cranial deformity to prevent further sequelae. Understanding the molecular mechanisms has allowed for the investigation of different therapeutic agents that can potentially be used to prevent the disorders. Further research efforts are need to better understand screening and effective methods of early intervention and prevention. Herein, the authors provide a comprehensive update on FGFR2-related syndromic craniosynostosis. |
High Reliability and Efficiency Single-Phase Transformerless Inverter for Grid-Connected Photovoltaic Systems | This paper presents a high-reliability single-phase transformerless grid-connected inverter that utilizes superjunction MOSFETs to achieve high efficiency for photovoltaic applications. The proposed converter utilizes two split ac-coupled inductors that operate separately for positive and negative half grid cycles. This eliminates the shoot-through issue that is encountered by traditional voltage source inverters, leading to enhanced system reliability. Dead time is not required at both the high-frequency pulsewidth modulation switching commutation and the grid zero-crossing instants, improving the quality of the output ac-current and increasing the converter efficiency. The split structure of the proposed inverter does not lead itself to the reverse-recovery issues for the main power switches and as such superjunction MOSFETs can be utilized without any reliability or efficiency penalties. Since MOSFETs are utilized in the proposed converter high efficiency can be achieved even at light load operations achieving a high California energy commission (CEC) or European union efficiency of the converter system. It also has the ability to operate at higher switching frequencies while maintaining high efficiency. The higher operating frequencies with high efficiency enables reduced cooling requirements and results in system cost savings by shrinking passive components. With two additional ac-side switches conducting the currents during the freewheeling phases, the photovoltaic array is decoupled from the grid. This reduces the high-frequency common-mode voltage leading to minimized ground loop leakage current. The operation principle, common-mode characteristic and design considerations of the proposed transformerless inverter are illustrated. The total losses of the power semiconductor devices of several existing transformerless inverters which utilize MOSFETs as main switches are evaluated and compared. The experimental results with a 5 kW prototype circuit show 99.0% CEC efficiency and 99.3% peak efficiency with a 20 kHz switching frequency. The high reliability and efficiency of the proposed converter makes it very attractive for single-phase transformerless photovoltaic inverter applications. |
Real time DDoS detection using fuzzy estimators | We propose a method for DDoS detection by constructing a fuzzy estimator on the mean packet inter arrival times. We divided the problem into two challenges, the first being the actual detection of the DDoS event taking place and the second being the identification of the offending IP addresses. We have imposed strict real time constraints for the first challenge and more relaxed constraints for the identification of addresses. Through empirical evaluation we confirmed that the detection can be completed within improved real time limits and that by using fuzzy estimators instead of crisp statistical descriptors we can avoid the shortcomings posed by assumptions on the model distribution of the traffic. In addition we managed to obtain results under a 3 sec detection window. a 2012 Elsevier Ltd. All rights reserved. |
Theory and Application of Digital Signal Processing | sprightly style and is interesting from cover to cover. The comments, critiques, and summaries that accompany the chapters are very helpful in crystalizing the ideas and answering questions that may arise, particularly to the self-learner. The transparency in the presentation of the material in the book equips the reader to proceed quickly to a wealth of problems included at the end of each chapter. These problems ranging from elementary to research-level are very valuable in that a solid working knowledge of the invariant imbedding techniques is acquired as well as good insight in attacking problems in various applied areas. Furthermore, a useful selection of references is given at the end of each chapter. This book may not appeal to those mathematicians who are interested primarily in the sophistication of mathematical theory, because the authors have deliberately avoided all pseudo-sophistication in attaining transparency of exposition. Precisely for the same reason the majority of the intended readers who are applications-oriented and are eager to use the techniques quickly in their own fields will welcome and appreciate the efforts put into writing this book. From a purely mathematical point of view, some of the invariant imbedding results may be considered to be generalizations of the classical theory of first-order partial differential equations, and a part of the analysis of invariant imbedding is still at a somewhat heuristic stage despite successes in many computational applications. However, those who are concerned with mathematical rigor will find opportunities to explore the foundations of the invariant imbedding method. In conclusion, let me quote the following: "What is the best method to obtain the solution to a problem'? The answer is, any way that works." (Richard P. Feyman, Engineering and Science, March 1965, Vol. XXVIII, no. 6, p. 9.) In this well-written book, Bellman and Wing have indeed accomplished the task of introducing the simplicity of the invariant imbedding method to tackle various problems of interest to engineers, physicists, applied mathematicians, and numerical analysts. |
Non-pharmacological treatment options for refractory epilepsy: an overview of human treatment modalities and their potential utility in dogs. | Refractory epilepsy is a common disorder both in humans and dogs and treatment protocols are difficult to optimise. In humans, different non-pharmacological treatment modalities currently available include surgery, the ketogenic diet and neurostimulation. Surgery leads to freedom from seizures in 50-75% of patients, but requires strict patient selection. The ketogenic diet is indicated in severe childhood epilepsies, but efficacy is limited and long-term compliance can be problematic. In the past decade, various types of neurostimulation have emerged as promising treatment modalities for humans with refractory epilepsy. Currently, none of these treatment options are used in routine daily clinical practice to treat dogs with the condition. Since many dogs with poorly controlled seizures do not survive, the search for alternative treatment options for canine refractory epilepsy should be prioritised. This review provides an overview of non-pharmacological treatment options for human refractory epilepsy. The current knowledge and limitations of these treatments in canine refractory epilepsy is also discussed. |
Modelling multivariate biomechanical measurements of the spine during a rowing exercise. | OBJECTIVE
To investigate the ability of statistical techniques to detect systematic changes in rowing technique during a rowing session and to discriminate between rowers of different abilities with and without back pain.
DESIGN
Statistical techniques were applied to kinematic datasets of elite level rowers, in order to construct an empirical model of the rowing stroke.
BACKGROUND
The size and complexity of datasets generated by biomechanical kinematics evaluations has led to opportunities for analysing pathology whilst introducing substantial challenges for statistical analysis.
METHODS
Spinal motion and load output of 18 International and National standard competitive rowers were monitored during ergometer rowing sessions. International rower data were used to construct an empirical model of this activity. Linear stroke models were derived using principal components and a generalized cross-validation procedure. Performance characteristics of the identified models were calculated for all rowing groups. The stroke model was applied to distinguishing pattern variations within and between rowers. A multivariate logistic regression analysis was carried out to examine the relationship between stroke model parameters on the incidence of low back pain.
RESULTS
90% of the variability in the data was explained by the first three principal component variables. Stroke models with three basis functions were selected for each variable. The models performed well on the National rowers, providing validation of the models. A 2-variable model showed a significant difference between the rowing stroke characteristics of rowers with and without low back pain (P<0.01).
CONCLUSIONS
A parsimonious collection of empirical models effectively describes motion and load characteristics of ergometer rowing. Patterns in rowing technique are found to be strongly associated with the incidence lower back pain.
RELEVANCE
Empirical statistical models can be used to track changes in rowing technique, and discriminate between different rowing groups. This may impact rowing training, and rehabilitation. |
Outlier Detection with Kernel Density Functions | Outlier detection has recently become an important problem in many industrial and financial applications. In this paper, a novel unsupervised algorithm for outlier detection with a solid statistical foundation is proposed. First we modify a nonparametric density estimate with a variable kernel to yield a robust local density estimation. Outliers are then detected by comparing the local density of each point to the local density of its neighbors. Our experiments performed on several simulated data sets have demonstrated that the proposed approach can outperform two widely used outlier detection algorithms (LOF and LOCI). |
Amorphous Fe Co Ni oxide for oxygen evolution reaction | Abstract Development of scalable, efficient and stable nonprecious metal electrocatalysts for oxygen evolution is of great significance in electrochemical water splitting. Multicomponent metal mixed oxides with controlled structures and compositions are recently considered as promising candidates to realize efficient oxygen evolution reaction at low overpotential. Herein, a Fe Co Ni gel with uniform dispersion of Fe/Co/Ni is prepared by a facile sol-gel method, followed by a vacuum drying process to obtain an amorphous ternary Fe Co Ni oxide. Of note, this strategy can be extended to synthesize other amorphous multicomponent metal oxides in force. Benefiting from the structural and compositional advantages, the as-prepared FeCoNiO x exhibits superior electrocatalytic performance for the oxygen evolution reaction in alkaline solution with an overpotential of only 240 and 203 mV at a current density of 10 mA cm −2 on a glassy carbon electrode and Ni foam electrode, respectively. The present approach provides some insight in design and synthesis of amorphous multicomponent metal oxide materials for energy storage and conversion applications. |
Graft maturity of the reconstructed anterior cruciate ligament 6 months postoperatively: a magnetic resonance imaging evaluation of quadriceps tendon with bone block and hamstring tendon autografts | The purpose of this study was to report the potential differences associated with graft maturity measured on magnetic resonance imaging (MRI) between quadriceps tendon with bone block and hamstring tendon autografts 6 months after ACL reconstruction. Twenty-six patients (15 male, 11 female; mean age 29.4 ± 17 years, range 13–46 years) who had undergone anatomic SB ACL reconstruction with either hamstring or quadriceps tendon with bone block autografts and had postoperative MRI 6 months after surgery. In 12 cases, the quadriceps tendon with bone block was used and hamstring in 14 cases. The signal/noise quotient was calculated to compare the difference between quadriceps tendon with bone block and hamstring autografts. Mean signal/noise quotient is lesser in quadriceps tendon with bone block (1.74 ± 0.39) compared with HS (2.44 ± 0.61) autografts (p = 0.020). For hamstring autograft, the distal region showed a significantly lower mean signal/noise quotient value compared with middle region, and the mean signal/noise quotient value in proximal region was the highest (distal vs middle p < 0.001; middle vs proximal p = 0.007; proximal vs distal p < 0.001). The mean signal/noise quotient of proximal region in quadriceps tendon with bone block autograft was lesser than that in hamstring. The middle region of the quadriceps tendon with bone block graft demonstrated the greatest signal/noise quotient [distal vs middle p = 0.001; middle vs proximal p = 0.027; proximal vs distal (n.s.)]. The maturity of quadriceps tendon with bone block was better in comparison with hamstring 6 months after anatomic SB ACL reconstruction. This study is clinically relevant in that modifying the individual rehabilitation according to the extent of graft maturity may be necessary to optimize patient function and prevent re-injury of the ACL graft. Retrospective case series, Level IV. |
A single sensor based PFC Zeta converter Fed BLDC motor drive for fan applications | A novel PFC (Power Factor Corrected) Converter using Zeta DC-DC converter feeding a BLDC (Brush Less DC) motor drive using a single voltage sensor is proposed for fan applications. A single phase supply followed by an uncontrolled bridge rectifier and a Zeta DC-DC converter is used to control the voltage of a DC link capacitor which is lying between the Zeta converter and a VSI (Voltage Source Inverter). Voltage of a DC link capacitor of Zeta converter is controlled to achieve the speed control of BLDC motor. The Zeta converter is working as a front end converter operating in DICM (Discontinuous Inductor Current Mode) and thus using a voltage follower approach. The DC link capacitor of the Zeta converter is followed by a VSI which is feeding a BLDC motor. A sensorless control of BLDC motor is used to eliminate the requirement of Hall Effect position sensors. A MATLAB/Simulink environment is used to simulate the developed model to achieve a wide range of speed control with high PF (power Factor) and improved PQ (Power Quality) at the supply. |
Unsupervised Word Segmentation in Context | This paper extends existing word segmentation models to take non-linguistic context into account. It improves the token F-score of a top performing segmentation models by 2.5% on a 27k utterances dataset. We posit that word segmentation is easier in-context because the learner is not trying to access irrelevant lexical items. We use topics from a Latent Dirichlet Allocation model as a proxy for “activities” contexts, to label the Providence corpus. We present Adaptor Grammar models that use these context labels, and we study their performance with and without context annotations at test time. |
Personalized PageRank Based Multi-document Summarization | This paper presents a novel multi-document summarization approach based on personalized pagerank (PPRSum). In this algorithm, we uniformly integrate various kinds of information in the corpus. At first, we train a salience model of sentence global features based on Naive Bayes Model. Secondly, we generate a relevance model for each corpus utilizing the query of it. Then, we compute the personalized prior probability for each sentence in the corpus utilizing the salience model and the relevance model both. With the help of personalized prior probability, a Personalized PageRank ranking process is performed depending on the relationships among all sentences in the corpus. Additionally, the redundancy penalty is imposed on each sentence. The summary is produced by choosing the sentences with both high query-focused information richness and high information novelty. Experiments on DUC2007 are performed and the ROUGE evaluation results show that PPRSum ranks between the 1st and the 2nd systems on DUC2007 main task. |
Inbreeding depression on female fertility and calving ease in Spanish dairy cattle. | Inbreeding depression on female fertility and calving ease in Spanish dairy cattle was studied by the traditional inbreeding coefficient (F) and an alternative measurement indicating the inbreeding rate (DeltaF) for each animal. Data included records from 49,497 and 62,134 cows for fertility and calving ease, respectively. Both inbreeding measurements were included separately in the routine genetic evaluation models for number of insemination to conception (sequential threshold animal model) and calving ease (sire-maternal grandsire threshold model). The F was included in the model as a categorical effect, whereas DeltaF was included as a linear covariate. Inbred cows showed impaired fertility and tended to have more difficult calvings than low or noninbred cows. Pregnancy rate decreased by 1.68% on average for cows with F from 6.25 to 12.5%. This amount of inbreeding, however, did not seem to increase dystocia incidence. Inbreeding depression was larger for F greater than 12.5%. Cows with F greater than 25% had lower pregnancy rate and higher dystocia rate (-6.37 and 1.67%, respectively) than low or noninbred cows. The DeltaF had a significant effect on female fertility. A DeltaF = 0.01, corresponding to an inbreeding coefficient of 5.62% for the average equivalent generations in the data used (5.68), lowered pregnancy rate by 1.5%. However, the posterior estimate for the effect of DeltaF on calving ease was not significantly different from zero. Although similar patterns were found with both F and DeltaF, the latter detected a lowered pregnancy rate at an equivalent F, probably because it may consider the known depth of the pedigree. The inbreeding rate might be an alternative choice to measure inbreeding depression. |
Inverse Reinforcement Learning Based Human Behavior Modeling for Goal Recognition in Dynamic Local Network Interdiction | Goal recognition is the task of inferring an agent’s goals given some or all of the agent’s observed actions. Among different ways of problem formulation, goal recognition can be solved as a model-based planning problem using off-theshell planners. However, obtaining accurate cost or reward models of an agent and incorporating them into the planning model becomes an issue in real applications. Towards this end, we propose an Inverse Reinforcement Learning (IRL)based opponent behavior modeling method, and apply it in the goal recognition assisted Dynamic Local Network Interdiction (DLNI) problem. We first introduce the overall framework and the DLNI problem domain of our work. After that, an IRL-based human behavior modeling method and Markov Decision Process-based goal recognition are introduced. Experimental results indicate that our learned behavior model has a higher tracking accuracy and yields better interdiction outcomes than other models. |
Paper in Business Analytics Feature Selection using LASSO | Which are the most relevant attributes to describe a response variable? This is one of the first question a researcher need to ask himself while analyzing a dataset, and the answer is not trivial. This research paper aims to explain and discuss the use of the LASSO method to address the feature selection task. Feature selection is a crucial and challenging task in the statistical modeling field, there are many studies that try to optimize and standardize this process for any kind of data, but this is not an easy thing to do. In the first chapter an introduction of feature selection task and the LASSO method are presented. In the second chapter we will apply the LASSO feature selection property to a Linear Regression problem, and the results of the analysis on a real dataset will be shown. Finally, in the third chapter the same analysis is repeated on a Generalized Linear Model in particular a Logistic Regression Model for a high-dimensional dataset. In the same chapter the findings of the scientific study of J.Chen and Z.Chen [4] are presented. |
Animal-inspired design and aerodynamic stabilization of a hexapedal millirobot | The VelociRoACH is a 10 cm long, 30 gram hexapedal millirobot capable of running at 2.7 m/s, making it the fastest legged robot built to date, relative to scale. We present the design by dynamic similarity technique and the locomotion adaptations which have allowed for this highly dynamic performance. In addition, we demonstrate that rotational dynamics become critical for stability as the scale of a robotic system is reduced. We present a new method of experimental dynamic tuning for legged millirobots, aimed at finding stable limit cycles with minimal rotational energy. By implementing an aerodynamic rotational damper, we further reduced the rotational energy in the system, and demonstrated that stable limit cycles with lower rotational energy are more robust to disturbances. This method increased the stability of the system without detracting from forward speed. |
A Role for the Superior Colliculus in Decision Criteria | Simple decisions arise from the evaluation of sensory evidence. But decisions are determined by more than just evidence. Individuals establish internal decision criteria that influence how they respond. Where or how decision criteria are established in the brain remains poorly understood. Here, we show that neuronal activity in the superior colliculus (SC) predicts changes in decision criteria. Using a novel "Yes-No" task that isolates changes in decision criterion from changes in decision sensitivity, and computing neuronal measures of sensitivity and criterion, we find that SC neuronal activity correlates with the decision criterion regardless of the location of the choice report. We also show that electrical manipulation of activity within the SC produces changes in decisions consistent with changes in decision criteria and are largely independent of the choice report location. Our correlational and causal results together provide strong evidence that SC activity signals the position of a decision criterion. VIDEO ABSTRACT. |
Security threats in cloud computing | Cloud computing is set of resources and services offered through the Internet. Cloud services are delivered from data centers located throughout the world. Cloud computing facilitates its consumers by providing virtual resources via internet. General example of cloud services is Google apps, provided by Google and Microsoft SharePoint. The rapid growth in field of “cloud computing” also increases severe security concerns. Security has remained a constant issue for Open Systems and internet, when we are talking about security cloud really suffers. Lack of security is the only hurdle in wide adoption of cloud computing. Cloud computing is surrounded by many security issues like securing data, and examining the utilization of cloud by the cloud computing vendors. The wide acceptance www has raised security risks along with the uncountable benefits, so is the case with cloud computing. The boom in cloud computing has brought lots of security challenges for the consumers and service providers. How the end users of cloud computing know that their information is not having any availability and security issues? Every one poses, Is their information secure? This study aims to identify the most vulnerable security threats in cloud computing, which will enable both end users and vendors to know about the key security threats associated with cloud computing. Our work will enable researchers and security professionals to know about users and vendors concerns and critical analysis about the different security models and tools proposed. |
Unsupervised Neural Machine Translation with Weight Sharing | Unsupervised neural machine translation (NMT) is a recently proposed approach for machine translation which aims to train the model without using any labeled data. The models proposed for unsupervised NMT often use only one shared encoder to map the pairs of sentences from different languages to a shared-latent space, which is weak in keeping the unique and internal characteristics of each language, such as the style, terminology, and sentence structure. To address this issue, we introduce an extension by utilizing two independent encoders but sharing some partial weights which are responsible for extracting high-level representations of the input sentences. Besides, two different generative adversarial networks (GANs), namely the local GAN and global GAN, are proposed to enhance the cross-language translation. With this new approach, we achieve significant improvements on English-German, EnglishFrench and Chinese-to-English translation tasks. |
Remote controlling an autonomous car with an iPhone | This paper describes iDriver, an iPhone software to remote control “Spirit of Berlin”. “Spirit of Berlin” is a completely autonomous car developed by the Free University of Berlin which is capable of unmanned driving in urban areas. iDriver is an iPhone application sending control packets to the car in order to remote control its steering wheel, gas and brake pedal, gear shift and turn signals. Additionally, a video stream from two top-mounted cameras is broadcasted back to the iPhone. |
Cloud Load Balancing Techniques : A Step Towards Green Computing | Cloud computing is emerging as a new paradigm of large-scale distributed computing. It is a framework for enabling convenient, on-demand network access to a shared pool of computing resources. Load balancing is one of the main challenges in cloud computing which is required to distribute the dynamic workload across multiple nodes to ensure that no single node is overwhelmed. It helps in optimal utilization of resources and hence in enhancing the performance of the system. The goal of load balancing is to minimize the resource consumption which will further reduce energy consumption and carbon emission rate that is the dire need of cloud computing. This determines the need of new metrics, energy consumption and carbon emission for energy-efficient load balancing in cloud computing. This paper discusses the existing load balancing techniques in cloud computing and further compares them based on various parameters like performance, scalability, associated overhead etc. that are considered in different techniques. It further discusses these techniques from energy consumption and carbon emission perspective. |
Adding Communicative and Affective Strategies to an Embodied Conversational Agent to Enhance Second Language Learners’ Willingness to Communicate | This paper describes an embodied conversational agent enhanced with specific conversational strategies aiming to foster learners’ readiness towards communication in a second language (L2). Willingness to communicate (WTC) in a second language is believed to have a direct and sustained influence on learners’ actual usage frequency of the target language. To help overcome the lack of suitable environments for increasing L2 learners’ WTC, our approach is to build embodied conversational agents that can help learners surmount their apprehension towards communication in L2. Here, we focus on the dialogue management aspects of our approach and propose a model based on a set of communication strategies (CS) and affective backchannels (AB) to foster such agents’ ability to carry on natural and WTC-friendly conversations with learners. We examined learners’ expected WTC after interacting with one of the following versions of the system: an agent featuring both CS and AB; an agent featuring only CS; and an agent featuring only AB. The results suggested that combining CS and AB empowers the conversational agent and leads to higher expected WTC among L2 learners. We also found that even the AB-only version of the system had the potential to enhance WTC to some extent. These findings are evidence of the feasibility of enhancing L2 learners’ engagement towards communication using a computer-based environment coupled with appropriate conversational strategies. |
PCBs in sediments of the Great Lakes--distribution and trends, homolog and chlorine patterns, and in situ degradation. | A region-wide data analysis on polychlorinated biphenyls (PCBs) in the sediment of the Great Lakes reveals a total accumulation of approximately 300+/-50 tonnes, representing a >30% reduction from the 1980s. Evidence of in situ degradation of sediment PCB was found, with estimated t(1/2) of 11 and 17 years, at two open water locations in Lake Ontario. The relative abundance of heavy homologs as well as para-chlorines decreases with increasing depth, while the opposite is true for medium and light homologs and ortho-chlorines. In Lake Michigan, the vertical pattern features enrichment of heavier congeners and reduction of ortho-chlorines in deeper sediment layers, opposite to the trend in Lake Ontario. PCBs decrease log-linearly with increasing latitude and longitude. Air deposition of PCBs to lake sediment decreases at about 0.077 ng cm(-2) yr(-1) per degree latitude (N) for the geographic region extending from the Great Lakes to within the Arctic Circle. |
Non-prescription treatment of NSAID induced GORD by Australian pharmacies: a national simulated patient study | Background Patients regularly present to community pharmacies for advice about and treatment for reflux symptoms and NSAIDs are a common cause of these symptoms. There is no published literature detailing the approach that pharmacies take to these enquiries, the pharmacotherapy they recommend or whether they contribute to the safe and effective use of reflux medicines. Objectives To assess in an observational study design the clinical history gathering, recommendations for GORD management and counselling provided by community pharmacies in a simulated patient scenario involving suspected NSAID induced reflux symptoms. Setting Australian community pharmacies. Method Simulated patients visited 223 community pharmacies to request treatment for reflux symptoms. The interaction was audiotaped and assessed against guidelines for the treatment of reflux symptoms. Main outcome measures Alignment of community pharmacies with international expert gastroenterologist guidance and national professional practice guidelines for the treatment of reflux symptoms by pharmacists including: consultation with a pharmacist; confirmation of reflux diagnosis based on symptoms; recommendation of short courses proton pump inhibitor (PPI) therapy; advice on the safe and effective use of reflux medicines and referral to a doctor for further assessment. Results Pharmacists consulted with the simulated patient in 77 % of cases. Symptoms were enquired about in 95 % of cases and a medicines history taken in 69 % of cases. Recommendations for treatment included: PPIs (18 %), histamine H2 antagonists (57 %) and antacids (19 %). Advice on product use was given in 83 % of cases. Referral to a doctor to discuss reflux symptoms was made in 63 % of cases. Conclusion When assessing patients for the symptoms of GORD, Australian pharmacists and non-pharmacist support staff take a comprehensive history including symptomatology, duration of symptoms, concomitant medicines and medical conditions and any GORD treatments previously trialled. They provide comprehensive counselling on the use of antisecretory and antacid medicines. Counselling could involve more comprehensive information on lifestyle approaches for GORD management and side effects of antisecretory and antacid medicines. Further alignment with guidelines for the management of GORD would result in greater referral to a doctor for assessment of recurrent GORD and greater recommendation of PPIs for symptoms. However alignment with guidelines by all pharmacists is unrealistic if the guidelines are not universally available to them. |
Phase I study of intraperitoneal metalloproteinase inhibitor BB94 in patients with malignant ascites. | This was an open Phase I study of i.p. matrix metalloproteinase inhibitor BB94 in patients with malignant ascites. The objective of the study was to determine the effect of increasing i.p. doses of BB94 with reference to the tolerance, safety, and pharmacokinetics of the compound. Twenty-three patients with malignant ascites had BB94 instilled into the peritoneal cavity after paracentesis. The compound was well tolerated; no serious adverse events were seen, and no specific toxicities were observed. High plasma concentrations were seen an hour after dosing, and BB94 was still present in the plasma at day 28 after treatment at levels in excess of the IC50 identified in preclinical studies. Five of the 23 patients neither reaccumulated ascites nor died up to 112 days after dosing. Seven patients died without reaccumulating ascites. Although the study was not designed to demonstrate clinical efficacy, the results were encouraging and support the further therapeutic evaluation of matrix metalloproteinase inhibitors in the management of malignant ascites. |
Capacitive Pressure Sensor With Very Large Dynamic Range | A new capacitive pressure sensor with very large dynamic range is introduced. The sensor is based on a new technique for substantially changing the surface area of the electrodes, rather than the inter-electrode spacing as commonly done at the present. The prototype device has demonstrated a change in capacitance of approximately 2500 pF over a pressure range of 10 kPa. |
Generating Stopword List for Sanskrit Language | In the era of information burst, optimization of processes for Information Retrieval, Text Summarization, Text and Data Analytic systems becomes utmost important. Therefore in order to achieve accuracy, redundant words with low or no semantic meaning must be filtered out. Such words are known as Stopwords. Stopwords list has been developed for languages like English, Chinese, Arabic, Hindi, etc but standard stopword list is still missing for Sanskrit language. Identifying stop words manually from Sanskrit text is a herculean task hence this paper reflects an automated stop word generator algorithm based on frequency of word and its implementation to ease the task. To fine-tune the generated list still manual intervention by language expert is required thus following a hybrid approach. The paper presents the first of its kind, a list of seventy-five generic stopwords of Sanskrit language extracted from a data amounting to nearly seventy-six thousand words. |
Unsupervised Calibration for Multi-beam Lasers | Keeping pace with technological progress, robot sensors are generating increasing amounts of data; a particular recent trend has been a shift from single-beam LIDAR sensors to multi-beam versions. Whereas single-beam sensors can often be calibrated without great difficulty, deriving an accurate calibration for lasers with many simultaneous beams has been a tedious and significantly harder challenge. In addition, existing calibration methods require specific and known environmental features. Instead, we propose a fully unsupervised approach to multibeam laser calibration. We attempt to recover optimal parameters for each beam’s orientation and distance-response functio n as well as a fully probabilistic generative model for each beam’s remittance response to surfaces of varying reflectivity. Our method allows simultaneous calibration of tens or hundreds of beams, each with its own parameters. In addition, we recover the sensor’s extrinsic pose relative to the robot’s coordinate frame. Crucially, our approach requires no specific calibration target, instead relying only on the weak assumption that points in space tend to lie on contiguous surfaces. Specifically, we define an energy function on point clouds that penalizes points far away from surfaces defined by points from other beams. Then, by aggregating points acquired across a series of poses, we take derivatives of the energy function across pairs of beams with respect to individual parameters. Using an iterative optimization method we arrive at a globally consistent calibration with very low error. Demonstrating our algorithm with a 64-beam LIDAR unit on a moving vehicle equipped with an IMU, we show that we can precisely solve for the LIDAR’s extrinsic pose and derive accurate 192-parameter orientation and distance calibrations even from grossly inaccurate initializations and without any calibration target or environment measurements. We also show significant improvements to the resulting remittance environment maps resulting from these calibrated parameters as well as the learned Bayesian model for each beam’s remittance response. |
Defining Emotion Concepts | This article demonstrates that emotion concepts-including the so-called basic ones, such as anger or sadness-can be defined in terms of universal semantic primitives such as ‘good’, ‘bad’, ‘do’, ‘happen’, ‘know’, and ‘want’, in terms of which all areas of meaning, in all languages, can be rigorously and revealingly portrayed. The definitions proposed here take the form of certain prototypical scripts or scenarios, formulated in terms of thoughts, wants, and feelings. These scripts, however, can be seen as formulas providing rigorous specifications of necessary and sufficient conditions (not for emotions as such, but for emotion concepts), and they do not support the idea that boundaries between emotion concepts are “fuzzy.” On the contrary, the small set of universal semantic primitives employed here (which has emerged from two decades of empirical investigations by the author and colleagues) demonstrates that even apparent synonyms such as sad and unhappy embody different-and fully specifiable-conceptual structures. |
Game-theoretic approach towards network security: A review | Advancements in information technology has increased the use of internet. With the pervasiveness of internet, network security has become critical issue in every organization. Network attacks results in massive amount of loss in terms of money, reputation and data confidentiality. Reducing or eliminating the negative effects of any intrusion is a fundamental issue of network security. The network security problem can be represented as a game between the attacker or intruder and the network administrator where both the players try to attain maximum outcome. The network administrator tries to defend the attack and the attacker tries to overcome it and attack the system. Thus network security can be enforced using game theoretic approach. This paper presents a review of game theoretic solutions developed for network security. |
Adjustable Autonomy for Human-Centered Autonomous Systems | ion is also critical to the success of planning and scheduling activities. In our scenarios, the crew will often have to deal with planning and scheduling at a very high level (e.g., what crops do I need to plant now so they can be harvested in six months) and planning and scheduling at a detailed level (e.g., what is my next task). The autonomous system must be able to move between various time scales and levels of abstraction, presenting the correct level of information to the user at the correct time. Model-based diagnosis and recovery When something goes wrong, a robust autonomous should figure out what went wrong and recover as best as it can. A model-based diagnosis and recovery system, such as Livingstone [Williams and Nayak, 96], does this. It is analogous to the autonomic and immune systems of a living creature. If the autonomous system has a model of the system it controls, it can use this to figure out what is the most likely cause that explains the observed symptoms as well as how can the system recover given this diagnosis so its mission can continue. For example, if the pressure of a tank is low, it could be because the tank has a leak, the pump blew a fuse, a valve is not open to fill the tank or not closed to keep the tank from draining. However, it could be that the tank pressure is not low and the pressure sensor is defective. By analyzing the system from other sensors, it may say the pressure is normal or suggest closing a valve, resetting the pump circuit breaker, or requesting a crewmember to check the tank for a leak. |
An assessment of food supplementation to chronically sick patients receiving home based care in Bangwe, Malawi : a descriptive study | BACKGROUND
The effect of food supplementation provided by the World Food Programme to patients and their families enrolled in a predominantly HIV/AIDS home based care programme in Bangwe Malawi is assessed.
METHODS
The survival and nutritional status of patients and the nutritional status of their families recruited up to six months before a food supplementation programme started are compared to subsequent patients and their families over a further 12 months.
RESULTS
360 patients, of whom 199 died, were studied. Food supplementation did not improve survival but had an effect (not statistically significant) on nutritional status. Additional oil was given to some families; it may have improved survival but not nutritional status.
CONCLUSION
Food supplementation to HIV/AIDS home based care patients and their families does not work well. This may be because the intervention is too late to affect the course of disease or insufficiently targeted perhaps due to problems of distribution in an urban setting. The World Food Programme's emphasis on supplementary feeding for these families needs to be reviewed. |
Wavelet based real-time smoke detection in video | A method for smoke detection in video is proposed. It is assumed the camera monitoring the scene is stationary. Since the smoke is semi-transparent, edges of image frames start loosing their sharpness and this leads to a decrease in the high frequency content of the image. To determine the smoke in the field of view of the camera, the background of the scene is estimated and decrease of high frequency energy of the scene is monitored using the spatial wavelet transforms of the current and the background images. Edges of the scene are especially important because they produce local extrema in the wavelet domain. A decrease in values of local extrema is also an indicator of smoke. In addition, scene becomes grayish when there is smoke and this leads to a decrease in chrominance values of pixels. Periodic behavior in smoke boundaries and convexity of smoke regions are also analyzed. All of these clues are combined to reach a final decision. |
How bees detect coloured targets using different regions of their compound eyes | Honeybees Apis mellifera detect coloured targets presented to the frontal region of their compound eyes using their colour vision system at larger visual angles (α > 15°), and an achromatic visual system based on the long-wave photoreceptor type at smaller visual angles (5° < α < 15°). Here we examine the capability of the dorsal, ventral and frontal regions of the eye for colour detection. The minimum visual angle αmin at which the bees detect a stimulus providing both chromatic contrast and receptor-specific contrasts to the three receptor types varies for the different regions of the eye: 7.1 ± 0.5° for the ventral region, 8.2 ± 0.6° for the dorsal region and 4.0 ± 0.5° for the frontal region. Flight trajectories show that when the target was presented in the horizontal plane, bees used only the ventral region of their eyes to make their choices. When the targets appeared dorsally, bees used the frontodorsal region. This finding suggests that pure dorsal detection of coloured targets is difficult in this context. Furthermore, αmin in the ventral plane depends on receptor-specific contrasts. The absence of S-receptor contrast does not affect the performance (αmin = 5.9 ± 0.5°), whilst the absence of M- and L-receptor contrast significantly impairs the detection task. Minimal visual angles of 10.3 ± 0.9° and 17.6 ± 3°, respectively, are obtained in these cases. Thus, as for many visual tasks, the compound eye of the honeybee shows a regionalisation of colour detection that might be related to peripheral or central specialisations. |
The ecology of adolescent activity and experience. | Twenty-five adolescents reported their daily activities and the quality of their experiences for a total of 753 times during a normal week, in response to random beeps transmitted by an electronic paging device. In this sample adolescents were found to spend most of their time either in conversation with peers or in watching television. Negative affects were prevalent in most activities involving socialization into adult roles. Television viewing appears to be an affectless state associated with deviant behavior and antisocial personality traits. The research suggests the importance of a systemic approach which studies persons' activities and experiences in an ecological context. The experiential sampling method described in this paper provides a tool for collecting such systemic data. |
NONDAMAGING RETINAL LASER THERAPY FOR TREATMENT OF CENTRAL SEROUS CHORIORETINOPATHY: What is the Evidence? | PURPOSE
To summarize the literature addressing subthreshold or nondamaging retinal laser therapy (NRT) for central serous chorioretinopathy (CSCR) and to discuss results and trends that provoke further investigation.
METHODS
Analysis of current literature evaluating NRT with micropulse or continuous wave lasers for CSCR.
RESULTS
Sixteen studies including 398 patients consisted of retrospective case series, prospective nonrandomized interventional case series, and prospective randomized clinical trials. All studies but one evaluated chronic CSCR, and laser parameters varied greatly between studies. Mean central macular thickness decreased, on average, by ∼80 μm by 3 months. Mean best-corrected visual acuity increased, on average, by about 9 letters by 3 months, and no study reported a decrease in acuity below presentation. No retinal complications were observed with the various forms of NRT used, but six patients in two studies with micropulse laser experienced pigmentary changes in the retinal pigment epithelium attributed to excessive laser settings.
CONCLUSION
Based on the current evidence, NRT demonstrates efficacy and safety in 12-month follow-up in patients with chronic and possibly acute CSCR. The NRT would benefit from better standardization of the laser settings and understanding of mechanisms of action, as well as further prospective randomized clinical trials. |
Data reorganization in memory using 3D-stacked DRAM | In this paper we focus on common data reorganization operations such as shuffle, pack/unpack, swap, transpose, and layout transformations. Although these operations simply relocate the data in the memory, they are costly on conventional systems mainly due to inefficient access patterns, limited data reuse and roundtrip data traversal throughout the memory hierarchy. This paper presents a two pronged approach for efficient data reorganization, which combines (i) a proposed DRAM-aware reshape accelerator integrated within 3D-stacked DRAM, and (ii) a mathematical framework that is used to represent and optimize the reorganization operations.
We evaluate our proposed system through two major use cases. First, we demonstrate the reshape accelerator in performing a physical address remapping via data layout transform to utilize the internal parallelism/locality of the 3D-stacked DRAM structure more efficiently for general purpose workloads. Then, we focus on offloading and accelerating commonly used data reorganization routines selected from the Intel Math Kernel Library package. We evaluate the energy and performance benefits of our approach by comparing it against existing optimized implementations on state-of-the-art GPUs and CPUs. For the various test cases, in-memory data reorganization provides orders of magnitude performance and energy efficiency improvements via low overhead hardware. |
A Novel MPPT Algorithm Based on Particle Swarm Optimization for Photovoltaic Systems | This paper describes a new maximum-power-point-tracking method for a photovoltaic system based on the Lagrange Interpolation Formula and proposes the particle swarm optimization method. The proposed control scheme eliminates the problems of conventional methods by using only a simple numerical calculation to initialize the particles around the global maximum power point. Hence, the suggested control scheme will utilize less iterations to reach the maximum power point. Simulation study is carried out using MATLAB/SIMULINK and compared with the Perturb and Observe method, the Incremental Conductance method, and the conventional Particle Swarm Optimization algorithm. The proposed algorithm is verified with the OPAL-RT real-time simulator. The simulation results confirm that the proposed algorithm can effectively enhance the stability and the fast tracking capability under abnormal insolation conditions. |
Adaptive Image Sampling and Windows Classification for On-board Pedestrian Detection | On–board pedestrian detection is in the frontier of the state– of–the–art since it implies processing outdoor scenarios from a mobile platform and searching for aspect–changing objects in cluttered urban environments. Most promising approaches include the development of classifiers based on feature selection and machine learning. However, they use a large number of features which compromises real–time. Thus, methods for running the classifiers in only a few image windows must be provided. In this paper we contribute in both aspects, proposing a camera pose estimation method for adaptive sparse image sampling, as well as a classifier for pedestrian detection based on Haar wavelets and edge orientation histograms as features and AdaBoost as learning machine. Both proposals are compared with relevant approaches in the literature, showing comparable results but reducing processing time by four for the sampling tasks and by ten for the classification one. |
Profile of Heavy Metals in Selected Medicinal Plants Used for the Treatment of Diabetes, Malaria and Pneumonia in Kisii Region, Southwest Kenya | Medicinal herbs are sources of chemical substances that have different biological activities including those useful in the treatment of human and animal diseases. Amongst the indigenous herbs used as phytomedicines for the treatment of diabetes, malaria and pneumonia in Kisii region, Southwest Kenya are Carissa spinarum, Urtica dioica, Warburgia ugandensis, Senna didymobotrya, Physalis Peruvian, Bidens pilosa, Leonotis nepetifolia and Toddalia asiatica. A study was carried out on these herbs in the year 2011 to 2012. The objective was to determine the essential and non-essential heavy metals present in the herbs and their levels. Leaf samples of these plants were obtained from Kisii region, washed, air-dried and milled. The samples were digested by wet digestion method and analysed by atomic absorption spectrometry. The essential and non-essential heavy metals in the plant extracts were quantified. As a guideline, FAO/WHO defined the permissible limits (ppm) of the various heavy metals in the consumed medicinal herbs for different countries as: chromium (2), manganese (44.6 to 339), iron (261 to 1239), cobalt (0.14 to 0.48), nickel (1.63), copper (20 to 150), zinc (27.4), cadmium (0.3), mercury (0.1) and lead (10). Results obtained in the present study showed that extracts of the medicinal herbs investigated contain heavy metals namely iron, chromium, copper, zinc, cobalt, manganese and nickel that are considered essential elements; and lead, cadmium and mercury which are nonessential. The concentration (ppm) of heavy metals in the plant extracts was found to be as follows: chromium (0.567 to 2.035), manganese (3.254 to 17.33), iron (0.967 to 6.067), cobalt (0.967 to 6.067), nickel (0.589 to 1.60), copper (0.305 to 1.44), zinc (0.989 to 1.833), cadmium (0.035 to 0.206), mercury (0.0024 to 0.00838) and lead (0.25 to 0.407). From the comparison of the results with the defined permissible limits, it was concluded that the levels of heavy metals present in the herbs fall in the permissible range for consumed medicinal herbs as defined for different countries. |
Pulmonary artery aneurysms in Behçet’s disease | Behçet’s disease is the most common cause of pulmonary artery aneurysms. Pulmonary artery aneurysms are rare, but they are life-threatening because of their high tendency to rupture. However, there is also a chance that the aneurysms may completely resolve with immunosuppressive therapy. A 30-year-old man was admitted with chest pain, painful oral and genital ulcers, skin rash, weakness, and intermittent hemoptysis. He had a history of Behçet’s disease for 6 years. The chest radiography showed a round opacity superior part of hilus on right. The helical thoracic computed tomography (CT) angiography demonstrated pulmonary aneurysms associated with Behçet’s disease. The patient was successfully treated with colchicine, corticosteroids, and cyclophosphamide. A discussion about pulmonary artery aneurysms associated with Behçet’s disease is provided in this case. |
International comparison of care for very low birth weight infants: parents' perceptions of counseling and decision-making. | OBJECTIVE
To characterize parent perceptions and satisfaction with physician counseling and delivery-room resuscitation of very low birth weight infants in countries with neonatal intensive care capacity.
STUDY DESIGN
Convenience sample of 327 parents of 379 inborn very low birth weight infants (<1501 g) who had received resuscitation and neonatal intensive care in 9 neonatal intensive care units (NICUs) in 6 Pacific Rim countries and in 2 California hospitals. The sample comprised mostly parents whose infants survived, because in some centers interviews of parents of nonsurviving infants were culturally inappropriate. Of 359 survivors for whom outcome data were asked of parents, 29% were reported to have long-term sequelae. Half-hour structured interviews were performed, using trained interpreters as necessary, at an interval of 13.7 months after the infant's birth. We compared responses to interview questions that detailed counseling patterns, factors taken into consideration in decisions, and acceptance of parental decision-making.
RESULTS
Parents' recall of perinatal counseling differed among centers. The majority of parents assessed physician counseling on morbidity and mortality as adequate in most, but not all, centers. They less commonly perceived discussions of other issues as adequate to their needs. The majority (>65%) of parents in all centers felt that they understood their infant's prognosis after physician counseling. The proportion of parents who expected long-term sequelae in their infant varied from 15% (in Kuala Lumpur, Malaysia) to 64% (in Singapore). The majority (>70%) of parents in all centers, however, perceived their infant's outcome to be better than they expected from physician counseling. A majority of parents across all centers feared that their infant would die in the NICU, and approximately one third continued to fear that their infant might die at home after nursery discharge. The parents' regard for physicians' and, to a lesser extent, partners' opinions was important in decision-making. Less than one quarter of parents perceived that physicians had made actual life-support decisions on their own except in Melbourne, Australia, and Tokyo, Japan (where 74% and 45% of parents, respectively, reported sole physician decision-making). Parents would have preferred to play a more active, but not autonomous, role in decisions made for their infants. Counseling may heighten parents' anxiety during and after their infant's hospitalization, but that does not diminish their recalled satisfaction with counseling and the decision-making process.
CONCLUSIONS
Counseling differs by center among these centers in Australasia and California. Given that parents desire to play an active role in decision-making for their premature infant, physicians should strive to provide parents the medical information critical for informed decision-making. Given that parents do not seek sole decision-making capacity, physicians should foster parental involvement in life-support decisions to the extent appropriate for local cultural norms. |
Introduction: fragmentation and integration in knowledge management research | Knowledge management (KM) research lacks a common conceptual core; it is cross-disciplinary, addresses a wide variety of phenomena, and has dif®culty distinguishing itself from many related areas of research. The result is a fragmented ®eld that is itself arti®cially split from the related literature on organizational learning. KM may be progressing through a predictable life-cycle that could end in collapse of the KM concept unless researchers can develop more integrative core theories of learningand knowledge-related phenomena in organizations. The diverse body of organizational learning and knowledge management research provides an impressive foundation for the synthesis of such broader theories of learning and knowledge that are creative, new, and integrative. |
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