The present disclosure features a high metal cation content zeolite-based binary catalyst (e.g., a high copper and/or iron content zeolite-based binary catalyst, where the zeolite can be a chabazite) for NOx reduction, having relatively low N2O make, and having low corresponding metal oxide content; where the metal in the metal oxide corresponds to the metal of the metal cation. The present disclosure also describes the synthesis of the zeolite-based binary catalyst having high metal cation content.

Internal combustion engine exhaust emissions, and especially diesel engine exhaust emissions, have come under scrutiny with the advent of stricter regulations, both in the U.S. and abroad. While diesel engines are known to be more economical to run than spark-ignited engines, diesel engines inherently suffer disadvantages in the area of emissions. For example, in a diesel engine, fuel is injected during the compression stroke, as opposed to during the intake stroke in a spark-ignited engine. As a result, a diesel engine has less time to thoroughly mix the air and fuel before ignition occurs. The consequence is that diesel engine exhaust contains incompletely burned fuel known as particulate matter, or "soot". In addition to particulate matter, internal combustion engines including diesel engines produce a number of combustion products including hydrocarbons ("HC"), carbon monoxide ("CO"), nitrogen oxides ("NOx"), and sulfur oxides ("SOx"). Aftertreatment systems may be utilized to reduce or eliminate emissions of these and other combustion products.
FIG. 1 shows a block diagram providing a brief overview of a vehicle powertrain. The components include an internal combustion engine 20 in flow communication with one or more selected components of an exhaust aftertreatment system 24. The exhaust aftertreatment system 24 optionally includes a catalyst system 96 upstream of a particulate filter 100. In the embodiment shown, the catalyst system 96 is a diesel oxidation catalyst (DOC) 96 coupled in flow communication to receive and treat exhaust from the engine 20. The DOC 96 is preferably a flow-through device that includes either a honeycomb-like or plate-like substrate. The substrate has a surface area that includes (e.g., is coated with) a catalyst. The catalyst can be an oxidation catalyst, which can include a precious metal catalyst, such as platinum or palladium, for rapid conversion of hydrocarbons, carbon monoxide, and nitric oxides in the engine exhaust gas into carbon dioxide, nitrogen, water, or NO2.
Once the exhaust has flowed through DOC 96, the diesel particulate filter (DPF) 100 is utilized to capture unwanted diesel particulate matter from the flow of exhaust gas exiting engine 20, by flowing exhaust across the walls of DPF channels. The diesel particulate matter includes sub-micron sized solid and liquid particles found in diesel exhaust. The DPF 100 can be manufactured from a variety of materials including but not limited to cordierite, silicon carbide, and/or other high temperature oxide ceramics.
The treated exhaust gases can then proceed through a compartment containing a diesel exhaust fluid (DEF) doser 102 for the introduction of a reductant, such as ammonia or a urea solution. The exhaust gases then flow to a selective catalytic reduction (SCR) system 104, which can include a catalytic core having a selective catalytic reduction catalyst (SCR catalyst) loaded thereon.
System 24 can include one or more sensors (not illustrated) associated with components of the system 24, such as one or more temperature sensors, NOx sensor, NH3 sensor, oxygen sensor, mass flow sensor, particulate sensor, and a pressure sensor.
As discussed above, the exhaust aftertreatment system 24 includes a Selective Catalytic Reduction (SCR) system 104. The SCR system 104 includes a selective catalytic reduction catalyst which interacts with NOx gases to convert the NOx gases into N2 and water, in the presence of an ammonia reductant. The overall reactions of NOx reductions in SCR are shown below.4NO+4NH3+O2→4N2+6H2O  (1)6NO2+8NH3→7N2+12H2O  (2)2NH3+NO+NO2→2N2+3H2O  (3)
Where Equation (1) represents a standard SCR reaction and Equation (3) represents a fast SCR reaction.
The performance of the SCR catalyst is often counterbalanced by catalyst durability. This challenge is further compounded by the increasingly stringent emissions regulatory demands on the one hand, and the economic pressure surrounding fuel economy on the other. Furthermore, the performance of the SCR catalyst is influenced by the level of engine out NOx (EO NOx) that has to be processed by the SCR catalyst. The current trend is in the direction of higher engine out NOx to improve fuel economy, while emission levels are simultaneously being reduced. For example, at present, EO NOx can reach as high as 7 g/kW-hr for at least a short period of time. However, it is anticipated that in the future, there will be a move towards very low tailpipe NOx (e.g., decreasing from about 0.2 to about 0.02 g/kW-hr).
High EO NOx has been shown to result in urea deposit build up in the SCR, due to the extremely high levels of diesel exhaust fluid that is introduced into the system, and insufficient residence time for complete decomposition to form NH3. The formation and accumulation of urea deposits on the SCR catalyst can result in severe damage to both the chemical and physical integrity of the SCR coating. Furthermore, the high intensity of diesel exhaust fluid dosing and the relatively long duration of the dosing in urea decomposition reactor can result in large quantities of water being released onto the SCR catalyst. As the SCR catalyst can be primarily composed of zeolites, which are powerful water adsorbing materials, the quantities of water can present a problem with both durability and cold start performance of the SCR catalyst.
At low EO NOx conditions, challenges are similar to those present under extended idling and cold start conditions. In other words, when SCR temperatures are too low for diesel exhaust fluid dosing and normal SCR operation (between about 250-450° C.), other strategies are required to meet emissions standards.
Without wishing to be bound by theory, it is believed that the advent of engine gas recirculation (EGR) has resulted in reduced peak in-cylinder temperatures for combustion to reduce engine out NON. The reduced peak in-cylinder temperatures are highly desirable from an emissions control perspective. However, the lower peak in-cylinder temperatures also result in undesirable lower fuel economy. The reduced engine exhaust temperatures that result from increasing use of EGR also have a negative impact on cold-start conditions for engine aftertreatment system (EAS) performance. Effective emissions control by EAS requires temperatures of at least 200° C. to be attained before DEF dosing may commence. Therefore, during the EAS heat-up period under cold-start conditions (i.e., at temperatures of less than 200° C.), there is no emissions control.
Thus, some challenges that are encountered in emissions control include:
(1) Cold-start conditions with relatively low engine exhaust temperatures. While cold start conditions can be addressed by close coupling the SCR to the engine to achieve maximum heat-up rate, with exposure of the SCR catalyst to non-pretreated exhaust directly from the engine; however, only partial NOx reduction can be achieved in this manner. Therefore, a second downstream SCR (or a SCRF) is required.
(2) Increased system size and complexity, which arise when the EAS includes a close coupled zeolite-based SCR, therefore, a DOC upstream of the SCR is required for NO2-make for optimal performance, with a DEF doser and an ammonia slip catalyst (ASC), also called an ammonia oxidation catalyst (AMOX), downstream of the SCR to decrease NH3 slip into the DOC. In some instances, while a close coupled vanadia-based SCR would not require a DOC upstream of the SCR, there exists a risk of sublimed vanadium escaping into the environment.
(3) Space limitations for close coupling, which require that the EAS be made more compact, for example, by combining SCR and DPF to form a SCRF, which presents the following challenges:
Competition between the fast SCR reaction and soot oxidation reaction for the available NO2 from the DOC;                (ii) No passive soot oxidation, because platinum group metals (PGMs) cannot be used on the DPF substrate due to the presence of NH3 for the SCR reaction. Oxidation of NH3 with PGMs also produces N2O, which is an undesirable greenhouse gas.        (iii) The reduced ash loading capacity of the SCRF relative to a DPF and the associated higher pressure change (ΔP) dictate a shorter ash cleaning interval and higher cost of ownership for the consumer.        (iv) The potential for NH3 and/or DEF to suppress passive soot oxidation due to:                    (a) Neutralization of NO2 by ammonium nitrate formation, and/or            (b) Deposition of undecomposed urea particulates onto the catalysts from DEF, which contribute to ΔP and potential catalyst poisoning.
(4) The potential for increased poisoning and hydrothermal aging of EAS catalysts are a major concern that arises from both close coupling of the SCR and in particular, when SCR on DPF (e.g., SCRF) technologies are employed.
(5) Increasingly stringent emissions regulations are likely to be enforced in the future; including tailpipe (TP) NOx≤0.02 g/kw-hr, lower N2O emissions standards, and generally tightened greenhouse gas regulation.
Without wishing to be bound by theory, it is believed that the properties of synthetic aluminosilicate zeolite molecular sieves form the basis of numerous commercially important catalytic, adsorption, and ion exchange applications due to a unique combination of high surface area, uniform porosity, and electrostatically-charged sites induced by tetrahedrally coordinated Al3+. It is believed that the active sites of zeolites can be modified and adsorbents and catalysts can be tailor-made for a wide range of uses.
Emissions control is one of the most important uses for zeolite-based catalysts. To increase copper loading, which leads to increased ammonia storage, two main strategies have been used by catalyst suppliers:
(1) Increased Al2O3 content of the zeolite (for locking Cu ions in place in the zeolite framework) increases the number of catalytic sites for ammonia storage and NOx reduction. For example, the Cu can be held in close association with the Al3+ sites of the framework by ion exchange forces (e.g., ionic bonds), and can have a certain degree of mobility and can be exchanged with other cationic species. However, higher Al2O3 content results in lower SiO2 content and reduced durability. Therefore, the optimum Si/Al ratio is considered to be 12, which provides a compromise between ammonia storage, NOx reduction, and catalyst durability. As used herein, the term "framework" refers to the crystal lattice of a given material.
(2) Prolonged (and often repeated) dilute copper exchange steps are required for achieving optimal copper loading in zeolite catalysts, while minimizing formation of copper oxide (CuO). Copper oxide is not catalytically active for NOx conversion, but is directly responsible for N2O formation, particularly in the presence of NO2. In particular, it is believed that formation of CuO occurs under two conditions:                (a) To decrease the likelihood of CuO formation during copper loading, very dilute copper solutions, extended ion exchange procedure times, and acid conditions (pH ˜3) are used. The acidic conditions maintain CuO in solution and decrease the likelihood of deposition on the zeolite crystal surface.        (b) Catalyst aging causes copper migration from the active sites created by Al2O3 content to form CuO crystals outside of the (Si/Al) framework. High copper loading in the zeolite framework tends to cause more than one copper ion in each location, thus facilitating CuO nanocrystal formation in the zeolite crystal upon aging. When nanocrystals of CuO form within the zeolite crystal, this can erode the crystal structure from the inside, and contribute to physical damage of the catalyst in the aging process (in addition to contributing to N2O-make). In order to minimize this occurrence, very dilute copper exchange solutions and long process times are employed. In addition, ion exchange is an equilibrium process, which sets a limitation on how much copper can be loaded into the available active sites of the zeolite during each loading step; thereby limiting catalytic activity. Thus, multiple copper loading steps with dilute solution is a common practice.
Prolonged ion exchange procedures in relatively dilute solution achieve the desired level of copper loading for conventional SCR catalysts. A strategy based upon decreasing (Si/Al) ratio enables the optimization of ammonia storage. However, this approach tends to reduce hydrothermal durability as aluminum content increases.
A strategy based upon decreasing (Si/Al) ratio enables the optimization of ammonia storage. However, this approach tends to reduce hydrothermal durability as aluminum content increases. Likewise, the manipulation of other process parameters to achieve the same goal can potentially reduce low temperature durability. Therefore, the achievement of ultra-low NOx emissions requires the development of new synthetic approaches for making catalyst compositions. The present disclosure seeks to fulfill these needs and provides further related advantages.

Ammonia facilitated cation loading of zeolite catalysts


Systems, methods, and devices are provided for performing a workflow with two or more electronic devices. Embodiments include an initiator electronic device that may function to control the workflow and send instructions for executing the workflow to a target electronic device. The initiator device may generate instructions for the workflow based on properties received from the target device. The instructions generated by the initiator may allow both devices to accomplish a shared goal, such as exchanging contact information. In some embodiments, the initiator device may include a graphical user interface for creating workflows, downloading workflows from a web service, and entering preferences governing the performance of the workflows.

1. Field of the Invention
Embodiments of the present disclosure relate generally to workflows that may be performed on electronic devices and, more particularly to shared execution of workflows on multiple electronic devices.
2. Description of the Related Art
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Consumers frequently store many types of data on electronic devices, such as cellular telephones, portable media players, laptop computers, and personal data assistants. For example, consumers may store contact information, calendar appointments, to-do lists, pictures, and links to web pages on electronic devices. Due to the increasing portability of electronic devices, consumers frequently share data stored on electronic devices with other people. For example, consumers may exchange shopping lists or contact information stored on electronic devices over the Internet, through flash drives, or over serial connections.
Typically, several actions are required to transfer data to and between electronic devices. For example, to create a new contact file, a consumer may perform the following steps: open a mail application, enter the contact person's phone number and email address, select a ring tone, open a camera application, take a picture of the person, and store the picture with the contact file. The consumer may frequently repeat the same series of steps each time a new contact is added. The consumer also may need to instruct the other person on how to generate or transmit the requested data. Further, electronic devices may operate using different operating systems and software applications. Additional steps may be required to convert information on one device into a format compatible with another device. The series of repeated steps may be complicated and time consuming.


A dry friction clutch plate is of the kind having a metallic support plate with ring-shaped friction pads arranged on either side of it. A ring-shaped compression element is arranged between the friction pads, this ring-shaped element being of a cellular material. The cellular material is a deformable material having open and/or closed cavities or pores such as to cause the thickness of the ring-shaped compression element to be reduced when the clutch plate is subjected to compressive stresses, and to cause it to revert to its original thickness on the removal of the compressive stresses.

Such a clutch plate is generally formed from a metallic support plate which includes axially deformable portions that constitute a progressive action device, with two ring-shaped friction pads being carried on either side of the support plate. The purpose of the progressive action device is firstly to enable progressive transmission to be received without snatching of the engine torque during an operation of engaging the clutch, and secondly to compensate for geometrical variations in the surface of the clutch.
The friction liners are usually attached to the support plate by riveting. This results in limitation of the useful thickness of each friction liner to that part which lies outside the level of the heads of the securing rivets. For this reason, the weight of the clutch plate is detrimentally increased, and in particular, its inertia is increased. This gives rise to difficulty in achieving synchronism during declutching and gear changing operations.
In order to avoid having to secure the friction pads by riveting, it has already been proposed to attach them adhesively on to flat metallic plates. Resilient arms, made of elastomeric material, are interposed in discrete zones. Such an arrangement is for example described in the specification of United States Pat. No. 2 253 316 and that of French Pat. No. 2 450 977.
In another type of construction, which is described in the specification of published European patent application No. EP 0 252 583A, the friction pads are secured on a flat metallic support plate through circular, concentric beads or bands of elastomeric material.
In these known expedients, the arms or bands of elastomeric material do however have the disadvantage that the elastomer is distributed unevenly. This gives rise to nonuniformity in the deformation of the progressive action device in the region of the friction pads, and also gives rise to premature wear of the latter because the heating which occurs in service is concentrated in zones having somewhat limited local zones of the friction pads.
An elastomeric material such as that used in the present state of the art as described above deforms by a flow action, provided that in all the zones concerned there is sufficient space to enable this to take place. This is in general not the case in known clutch plates.


A method and system for detecting a keylogger on a computer is described. One illustrative embodiment creates, in a memory of the computer, a hidden window; generates a unique, unpredictable data pattern; inputs, to the hidden window, the unique, unpredictable data pattern in a manner that mimics keyboard input from a user; scans running processes in the memory other than a keylogger detection process for the unique, unpredictable data pattern; and performs a secondary scan of a suspect process, the suspect process having an associated buffer that contains the unique, unpredictable data pattern.

Protecting personal computers from a never-ending onslaught of pestware or malware has become increasingly important and challenging. Some types of pestware or malware can compromise a user's privacy by sending sensitive information about the user or the user's computer to a remote destination without the user's knowledge or permission. Such malware is commonly referred to as "spyware." One particular type of spyware, a "keylogger," secretly records a user's keystrokes as the user types on a keyboard and captures the resulting text in a data file, which is often encrypted. The keylogger may also secretly send the captured data file to a remote destination by e-mail or some other communication protocol. Such a keylogger can be used by a remote party to acquire information such as credit card numbers, social security numbers, and other sensitive information.
Clearly, computer users have a strong motivation to detect and remove unwanted keyloggers from their systems. Many computer users rely on anti-spyware programs to detect and remove such threats. Since keyloggers are usually designed to be difficult to detect, however, conventional anti-spyware programs may fail to detect them quickly and effectively. It is thus apparent that there is a need in the art for an improved method and system for detecting a keylogger on a computer.

Method and system for detecting a keylogger on a computer


A method, apparatus, and computer program product are provided for training a neural network or providing a pre-trained neural network with the weight-updates being compressible using at least a weight-update compression loss function and/or task loss function. The weight-update compression loss function can comprise a weight-update vector defined as a latest weight vector minus an initial weight vector before training. A pre-trained neural network can be compressed by pruning one or more small-valued weights. The training of the neural network can consider the compressibility of the neural network, for instance, using a compression loss function, such as a task loss and/or a weight-update compression loss. The compressed neural network can be applied within a decoding loop of an encoder side or in a post-processing stage, as well as at a decoder side.

Neural networks are being utilized in an ever-increasing number of applications for many different types of devices, such as mobile phones and various internet of things (IoT) devices. Neural networks may be used to, e.g., image and video analysis and processing, social media data analysis, and device usage data analysis.
Running neural network(s) require large memory and computational resources. Requirements for large memory and computational resources prohibit efficient use of neural networks and deployment of neural network(s) to devices having limited memory and computational resources, such as mobile phones and IoT devices. Further, transmission of neural networks among devices may be cumbersome, since transmission requires substantial bandwidth.

Compressing weight updates for decoder-side neural networks


An internal data storage unit stores distributed music data. A copyright management table stores a process right to each music data item. The process right includes a playback right and a right to copy the data to an external storage medium. A control unit refers to the stored process right to determine whether an inputted instruction can be executed. If determining that the instruction can be executed, the control unit supplies a control signal to a playback unit or another relevant process unit. A display unit displays the stored process right based on an operation mode set in a mode storage unit. The playback and copy rights to the data are displayed with icons. If an icon indicating a copyright in use is selected, information is displayed about the external medium to which the data was copied. If the inputted instruction cannot be executed, a warning screen is displayed.

1. Field of the Invention
The present invention relates to a method and apparatus for processing copyrighted data, and more specifically, to a method and apparatus for processing copyrighted data that is distributed through a network.
2. Description of the Background Art
In recent years, various digitized information has become widely available, and a large number of digital productions have been distributed with multimedia contents including images and sounds. Such digital productions are provided for users through recording media such as CD-ROMs or communication means such as the Internet. Downloading digital productions to personal computers through a communication network is especially a convenient distribution method, and therefore this method is expected to spread increasingly. Digital productions are easy to copy without deteriorating the characteristics thereof. For this reason, copyright protection for digital productions is highly required.
The following conventional arts have been known for protecting the copyright for digital productions. A first conventional art is a contents control method which is used in a music distribution system, which has been published in "Internet-based music distribution requires immediate improvements in copyright protection technologies", Nikkei Electronics, Issue, no. 738, Mar., 8, 1999, PP. 87∝111. In the contents control method, a file containing encrypted music data (hereinafter referred to as file A) and a file containing control information, a decryption key for decrypting the file A, and other data (hereinafter referred to as file B) are distributed through a communication network. To play back the music data that is contained in the file A, it is determined, with reference to the control information contained in the file B, whether or not the file A is allowed to be played back or copied.
FIG. 17 is a block diagram showing the structure of a data processing apparatus which uses the first conventional art. The data processing apparatus shown in FIG. 17 is connected to a communication network (not shown) when the data processing apparatus is in use. A distributed data storage unit 101 stores the file A that is distributed through a communication network such as the Internet and CATV (Cable TV). A copyright management table 102 stores the file B that is distributed through the communication network in relation to the file A. A purchase process unit 103 communicates with a billing server (not shown) to purchase a process right that is required for playback and other processes, and records the purchased process right in the copyright management table 102. When an instruction is inputted by an input unit 104, a control unit 105 determines, with reference to the process right recorded in the copyright management table 102, whether the instruction is to be executed or not. A playback unit 106 receives a decryption key that is contained in the file B from the control unit 105, and plays back the music data that is contained in the file A.
As a second conventional art, a method of preventing unauthorized copying of digital data by encrypting the digital data has been known, which is disclosed in Japanese Patent Laid-Open Publication No. 9-320192 (1997-320192). FIG. 18 is a diagram showing the structure of a copyright protection apparatus according to the second conventional art. The copyright protection apparatus shown in FIG. 18 is characterized in that digital data that is read from a disk 111 is encrypted before being placed on a bus 114. In other words, a data format unit 112 provides the data that is read from the disk 111 with encryption start information, an encryption key, information about a unit of encryption, copy management information indicating whether data copying is allowed or not, and identification information of an encryption algorithm to be used. An encryption unit 113 encrypts the data by using the encryption key that is provided by a key delivery unit 110. The encrypted data flows on the bus 114. A decryption unit 115 decrypts the data by using a decryption key that is provided by the key delivery unit 110. The decrypted data is restored by a data format unit 116 to the state in which the digital data was read from the disk 111, and then the restored data is played back by a playback unit 117.
As such, according to the first conventional art, received copyrighted data can be processed within a purchased process right, while, according to the second conventional art, copyrighted data can be protected from unauthorized copying.
In these conventional arts, however, the process right that is required for processing copyrighted data is not presented to the user in an appropriate manner. Therefore, the user cannot recognize which process can be executed on each data item.

Copyrighted data processing method and apparatus

Matsushita Electric Industrial Co., Ltd.


When a malfunction nozzle occurs in a joint portion of print elements in a print head, the print head is controlled to minimize image impairments caused by the malfunction nozzle. This prevents an increase in cost of the print head and increases the printing speed while at the same time realizing a high quality of printed image. For the control of the overlapping nozzles in the adjoining print chips, a desired control mode is selectively set from among a plurality of control modes, the control modes having different nozzles removed from use.

1. Field of the Invention
The present invention relates to an ink jet printing apparatus that forms an image by using a print head having a plurality of print elements each comprising a plurality of ink ejection nozzles arrayed in line. The present invention also relates to an ink jet printing method, a method of setting a print control mode, and a program.
2. Description of the Related Art
A printing apparatus of an ink jet system (ink jet printing apparatus) that ejects ink from nozzles arrayed in an ink jet print head to form an image on a print medium is finding a wide range of applications in such equipment as printers, facsimile machines and copying machines. A color printer capable of forming a color image using a plurality of color inks, in particular, is becoming increasingly popular as its print quality is enhanced.
In such ink jet printing apparatus, an increased printing speed as well as the enhanced print quality constitutes an important factor for their widespread use. An effort to increase the printing speed is being made, which includes increasing a drive frequency of ink ejection from the print head and using a greater number of nozzles arrayed in the print head. A technique currently available to dramatically enhance the printing speed, for example, involves elongating the print head and increasing a nozzle arrangement density to print in one scan an image that is otherwise printed in a plurality of scans.
Among the methods for elongating the print head, it is the most desirable in terms of production cost to arrange a plurality of print heads in line. More specifically, where each of the print heads is constructed of a chip having a plurality of nozzles, an elongate print head is formed by arranging in line the same number of chips as the print heads. In the following description a portion connecting the adjoining chips, each composed of a plurality of nozzles, is taken as a joint between the print heads.
At a portion of the printed image corresponding to the joint between the print heads, an image flaw that looks like a white line is likely to be produced. This is caused by a phenomenon in which an air flow produced between the print head and the print medium deflects ink droplets coming out of those nozzles at the ends of a nozzle column toward the inside of the nozzle column. As a result, the ink droplets fail to land where they are intended (this is also called an "end dot deflection"). Other possible causes for the stripe-like image defect include a difference in ink ejection volume among the print heads, a precision of arranging a plurality of print heads in line, and variations in time taken by ink droplets to land on the print medium.
To prevent such a stripe-like image flaw that occurs at a part of the printed image corresponding to the joint between the print heads, a method has been proposed, as in Japanese Patent Disclosure No. 5-57965, which overlaps the nozzles at the joint portion of the print heads.
In the ink jet print head, however, there is a possibility of ink droplets failing to be ejected normally (so-called "ejection failure"), which may be caused by dirt that enters into nozzles during manufacture, degradation of nozzles over the long period of use, and deterioration of ink ejection elements. If such faulty nozzles occur at the joint portion between the print heads, they in combination with the "end dot deflection", the cause of the stripe-like image flaw, may produce more serious image impairments.
Even if the nozzles are not completely in the ejection failure state, the stripe-like image impairments such as caused by the ejection failure would likely occur also when the ink droplet ejection direction greatly deviates from an intended direction (also called an "excessive ejection deflection") or when the ink droplet ejection volume differs greatly from the desired one (also referred to as an "ejection volume variation" or "drop diameter variation"). If nozzles in such an "excessive ejection deflection" state or "ejection volume variation" state should occur in the joint portion between the print heads, worse image impairments would result.
To realize both an increased printing speed and an enhanced print image, a method may be conceived that uses two print heads that eject inks of the same color and performs one print head scan to print at high speed with almost the same level of image quality that can be achieved with two scans (this method is referred to also as a "dual head configuration"). In this dual head configuration, if abnormal nozzles in the state of "ejection failure", "excessive ejection deflection" or "ejection volume variation" should occur in one print head, the nozzles in the other print head that ejects the same color ink can complement the printing operation in place of the abnormal nozzles. However, if those nozzles of the second print head that are supposed to perform the complementary printing have troubles such as "ejection failure", "excessive ejection deflection" or "ejection volume variation", the desired complementary printing cannot be done.
The "ejection failure", "excessive ejection deflection" and "ejection volume variation" of the abnormal nozzles have been able to be suppressed in the frequency of occurrence by improving the print head manufacturing environments and thus have not posed a serious problem. However, when two or more print heads are arrayed in line to increase the number of nozzles for faster printing speed, the "ejection failure", "excessive ejection deflection" or "ejection volume variation" of the abnormal nozzles cannot be ignored. Efforts to produce print heads that do not include abnormal nozzles or which do not easily cause "ejection failure" will entail an increase in manufacturing cost, making the print heads very expensive.

Ink jet printing apparatus, ink jet printing method, method of setting print control mode, and program


A privacy-preserving index system addresses the problem of providing a privacy-preserving search over distributed access-controlled content. Indexed documents can be readily reconstructed from inverted indexes used in the search. The privacy-preserving index system builds a centralized privacy-preserving index in conjunction with a distributed access-control enforcing search protocol. The privacy-preserving index utilizes a randomized algorithm for constructing a privacy-preserving index. The privacy-preserving index is strongly resilient to privacy breaches. The privacy-preserving index system allows content providers to maintain complete control in defining access groups and ensuring its compliance, and further allows system implementors to retain tunable knobs to balance privacy and efficiency concerns for their particular domains.

While private and semi-private information on the Internet has grown rapidly in recent years, mechanisms for searching this information have failed to keep pace. A user faced with the problem of locating an access-controlled document would typically identify and individually search each relevant repository, assuming of course the user knows and remembers which repositories are relevant.
For example, company XYZ wishes to share some but not all of their internal research documents with company ABC. The documents that company XYZ wishes to share might refer to a collaborative project between the two companies. Company XYZ would like to be able to offer a search facility for that data, where company ABC can only search for documents to which they have access. However, company XYZ does not want company ABC to be able to determine what company XYZ is sharing with company Q. Currently, no method exists for uniformly searching data in this format between companies and individuals wishing to share data in an access-controlled format.
The lack of tools for searching access-controlled content on the network stems from the considerable difficulty in creating a search-engine that indexes the content while respecting the security and privacy requirements of the content providers. Contemporary search engines build inverted indexes that map a keyword to its precise locations in an indexed document.
Conventional inverted indexes represent an indexed document in its virtual entirety. The indexed document can thus be easily reconstructed from the index. The trust and security thus required of any host providing such an index over access-controlled content is enormous. Conferred with knowledge of every searchable document, the trust required of a search engine over access-controlled content grows rapidly with each participating provider. This enormous trust requirement, coupled with the potential for a complete breach of access control by way of malicious index disclosure, render such an approach impractical.
Conventional search solutions include centralized indexing, query broadcasting, distributed indexing, and centralized fuzzy indexing. The most common scheme for supporting efficient search over distributed content is centralized indexing, in which a centralized inverted index is built. The index maps each term to a set of documents that contain the term. The index is queried by the searcher to obtain a list of matching documents. This is the scheme of choice of web search engines and mediators
Centralized indexing can be extended to support access-controlled search by propagating access policies along with content to the indexing host. The index host applies these policies for each searcher to filter search results appropriately. Since only the indexing host needs to be contacted to completely execute a search, searches are highly efficient. However, a centralized index may allow anyone who has access to the index structure to "provably expose" content providers. A provable exposure occurs when an adversary (i.e., hacker) can provide irrefutable evidence that provider p is sharing document d. In cases where the index host is completely trusted by all content providers, this violation of access control may be tolerable. Finding such a trusted host is immensely difficult. Further, compromise of the index host by hackers could lead to a complete and devastating privacy loss should the index be revealed publicly.
At the other end of the search efficiency spectrum lie query broadcasting, broadcast-based schemes that send the query to all participating content providers. Such schemes include a network of content providers, where providers locally evaluate each query and directly provide any matching documents to the searcher. The query broadcasting search protocol may be augmented to implement access control. In such a protocol, the query will be broadcast along with the identity and IP address of the query originator. Providers could securely deliver search results back to the authenticated searcher over an encrypted connection to avoid interception.
Since content shared by a provider p resides at the provider's database alone, providers are assured absolute privacy and the goal of content privacy is naturally preserved. However, while this adaptation to query broadcasting has excellent privacy characteristics, it suffers from poor scalability and severe performance penalties. Consequently, the protocols for query broadcasting adopt heuristics (e.g., time-to-live fields) that limit search horizons and compromise search completeness.
The performance limitations of query broadcasting have led to work on distributed indexing methods that support efficient search without the need for a single centralized index provider. For example, a peer-to-peer network may leverage "super-peers" (machines with above-average bandwidth and processing power) by having them host sub-indexes of content shared by several less capable machines.
Another system distributes a search index using a distributed hash table. In these systems, the distributed index is used to identify a set of documents (or machines that host the documents) matching the searcher's query. These machines are then contacted directly by the searcher to retrieve the matching documents.
Access control for distributed indexing systems can be supported by simply having the providers enforce their access policies before providing the documents. However, much as in the case of a centralized index, any node with access to a portion of the distributed index can provably expose any of the providers indexed by that portion.
Further, indexes are typically hosted by untrusted machines over whom the providers themselves have no control. An active adversary that does not host a portion of the index can search the distributed index to inflict privacy breaches. For example, the adversary can determine the precise list of providers sharing a document with a particular keyword by issuing a search on that keyword, breaching content privacy with provable exposure. Content privacy can also be breached by mounting phrase attacks. Such attacks take advantage of the observation that most documents have characteristic sets of words that are unique to them.
To identify a provider sharing some document, the adversary need only compose a query consisting of such terms for the document. The resulting list of sites are then known to share the document but with possible innocence. Possible Innocence occurs when the claim of an adversary about provider p sharing document d can be false with a non-trivial probability. By choosing an appropriate set of terms, the adversary can achieve a near provable exposure.
Some search applications do not maintain precise inverted index lists, but instead maintain structures that allow mapping of a query to a "fuzzy" set of providers that may contain matching documents; this approach is called centralized fuzzy indexing. A bloom filter index, which is a type of a fuzzy index, can be probed by a searcher to identify a list of all providers that contain documents matching the query. The list however is not necessarily precise, since bloom filters may produce false positives due to hash collisions. Given such a list, the searcher contacts each provider to accumulate results. These schemes can be extended to support access-controlled searches by having the providers enforce their access policies at the point a searcher requests matching documents.
Bloom filter indexes do offer limited privacy characteristics by virtue of potential false positives in the list of providers. Each provider in the list is thus possibly innocent of sharing a document matching the query. However, this privacy is spurious. An active adversary can perform a dictionary-based attack on the Bloom filter index to identify the term distribution of any indexed provider.
Dictionary-based attacks take advantage of the fact that sentences in natural language (e.g., English) use words from a restricted vocabulary that are easily compiled (e.g., in a Oxford/Webster dictionary). Thus, the adversary can compute a hash for each word in the vocabulary. A provider in the Bloom filter entry for such a hash is, with some probability, sharing a document with the corresponding word. In addition, the scheme remains prone to phrase attacks.
While these conventional search solutions might be adapted to support searches over access-controlled content, such adaptations fail to adequately address privacy and efficiency. Any search mechanism that relies on a conventional search index allows a provider to be "provably exposed" because of the precise information that the index itself conveys. Efficient privacy-preserving search therefore requires an index structure that prevents breaches of "content privacy" even in the event that the index is made public.
What is needed is a system and associated method that will allow searchers privileged access to access-controlled documents without exposing the contents of the document, the provider of the document, or even existence of the document to unauthorized searchers. The need for such a system and method has heretofore remained unsatisfied.

Uniform search system and method for selectively sharing distributed access-controlled documents

International Business Machines Corporation


A current input interface circuit of a mouse circuit includes a first current mirror circuit connected to a second current mirror circuit permitting the mouse signal inputted thereto by the current parameter instead of voltage parameter thus constituting a current comparator.

This invention relates to a current-input type interface circuit of a mouse, especially for one interface circuit in which current parameters instead of voltage parameters are utilized to constitute the input parameters for a mouse.
The presently available mice all have a ball to frictionally drive two rollers to respectively correspond to the shift of the mouse in X and Y directions. Each roller coaxially carries a photogrid (optic interrupter) which co-rotates with the roller, thus the X and Y displacements can be photoelectrically converted into corresponding electrical signals. Two photo-coupling sensors each cooperates with one of the corresponding roller to sense the X displacement or Y displacement.
Referring to FIG. 4, either of the photo-coupling sensors comprising a light emitting diode (LED) 51 and a photo-transistor 52, which are respectively arranged at the opposite sides of the photogrid device, generates pulsative signal similar to a train of pulses. The frequency of the pulse-like signal represents the displacement of X-axis (Y-axis), thus reflecting the displacement and the direction of the mouse. Referring to FIG. 3, a mouse-input sensing circuit 53 receives the pulse-like signal from the photo-transistor 52 and transmits the signal to a control/processing circuit 54 for converting the pulse-like signal into a standard digital signal. An output circuit 56 is provided to promote the signal level of the digital signal from the control/processing circuit 54 and to give an output signal receivable/readable by a computer.
The mouse-input sensing circuit 53 used at the present time comprises a resistor R and an inverter 531, as shown in FIG. 5. The resistor R is connected between the emitter electrode of the photo-transistor 52 and a grounding point. The input of the inverter 531 is also connected to the emitter electrode of the photo-transistor 52. When the photo-transistor 52 receives the light emitted from the diode 51, an electrical signal is produced, so a potential is obtained across the resistor R. The signal is further inverted by means of the inverter 531 and outputted at the output terminal 0/P for driving subsequent circuits. Therefore, the mouse-input sensing circuit 53 cooperates with the photo-transistor 52 to generate required voltage to drive the subsequent circuits. However, the mouse-input sensing circuit 53 is integrated in a mouse control chip, the manufacturing process of which affects the stability of the input voltage and the response speed as described below.
Due to the manufacturing process of the integrated circuit, the transition point of the inverter 531 has a relatively large range of errors; also the receiving characteristic of each photo-transistor 52 has its individual difference; the conducting current of the photo-transistor is relatively small (possibly lower than 5 micro-ampere), thus causing the insufficient tolerance of the transition of the inverter 531. For example, if the transition point of the inverter 531 is 1.4 volts, the resistor R should be 280 K-ohm during the minimum current (5 micro-ampere). The relatively high resistance (280 K-ohm) of the resistor R requires a relatively large area in the integrated circuit, contrary to the trend of miniaturization for integrated circuit. Moreover, due to the offset of the manufacturing process, the practical resistance might have an error up to 20%, i.e., the real resistance of the resistor R might vary in the range between 233 K-ohm and 336 K-ohm. If the resistance is 233 K-ohm, the output voltage is only 1.16 volts, which is not enough to enable the inverter 531 to transit its status. One could solve this problem by increasing the resistance of the resistor R. However, the increased resistance will lead to reduction of the V.sub.CE value of the photo-transistor to a too small value, thus causing the transistor 52 to enter its saturation status and decreasing its response speed. For example, when the photo-transistor 52 receives a total bombardment of the emitted light, the current therethrough might be as high as 40 to 50 micro-ampere. If the resistor is 280 K-ohm (notice that the 280 K-ohm falls in the above mentioned range between 233 K-ohm and 336 K-ohm), the potential across the resistor R is up to 11.2 volts, which is greater than the source voltage 5-volt. Therefore, the voltage will actually not undergo the above situation, but remain in a certain equilibrium point, which renders the V.sub.CE relatively small, thus causing the photo-transistor 52 to enter its saturation status. At this time, if the photo-grid device rotates in a too high speed, then the photo-transistor will not be able to catch up to timely respond with a switching over (from ON to OFF, or vise versa), thus causing the malfunction (wrong interpretation) of the mouse. Therefore, the resistance of the resistor R of the conventional voltage-input sensing circuit must neither be too great nor too small, and must be restricted in a narrow range. However, such an accuracy in resistance is practically very difficult for circuit integration.

Current-input type interface circuit of a mouse


The disclosure provides a method and an apparatus for re-establishing a radio link. The method comprises: a destination base station receiving a re-establishment request message sent by a User Equipment (UE), a cell identifier and an identifier of the UE are carried in the re-establishment request message, and attribute information used for indicating UE handover success or handover failure is carried in the cell identifier and the identifier of the UE (S102); and the destination base station determining, according to the attribute information, a security algorithm applied to radio link re-establishment between the destination base station and the UE, and establishing a radio link using the security algorithm (S104). The disclosure solves the problem in the related art that the radio link re-establishment fails as a security algorithm fallback process fails, thereby improving the success rate of radio link re-establishment.

When a User Equipment (UE) hands over, after the UE hands over to a destination side E-UTRAN Node B (eNB), the UE needs to adopt a new security algorithm configuration; however, for a scenario of UE handover failure, the UE will initiate a re-establishment request and fall back the security algorithm to an old security algorithm (that is, the security algorithm used by a source side eNB); therefore, as mentioned in the related art, when the UE hands over, the source side eNB needs to transfer the security algorithm thereof to the destination side eNB for being used under a scenario of radio link re-establishment.
However, in the related art, transferring the security algorithm of the source side eNB to the destination side eNB is mentioned only, which is used in the potential scenario of radio link re-establishment, and specific scenarios of radio link re-establishment are not distinguished; however, there are a variety of scenarios of radio link re-establishment; some of the scenarios of radio link re-establishment are not caused by the UE handover failure; and in this scenario, the problem of fallback process failure will occur based on the security algorithm of the UE falling back to the old security algorithm.
For example, in a scenario of non-competition handover, the UE receives an Msg 2 (a randomly accessed second message), at the moment, the UE considers that the handover succeeds; however, due to the quality problem of a radio link, when a re-configuration complete message is sent to the destination side eNB, Radio Link Control (RLC) layer at a user surface of the UE exceeds the maximum times of re-transmission, and at the moment, the UE could also initiate the re-establishment request to the destination side eNB; according to the related art, since the destination side eNB does not receive the re-configuration complete message, the destination side eNB considers that the handover does not succeed, at the moment the security algorithm of the UE will be updated to the old security algorithm based on receiving the re-establishment request; however, at the moment, since the UE considers that the handover succeeds, the security algorithm used by the UE has been a new security algorithm, but because of the failure of sending the re-configuration complete message to the destination side eNB, the UE sends the re-establishment request to the destination side eNB, which is not caused by the UE handover failure in a real sense; therefore, the security algorithm fallback process performed by the destination side eNB is bound to fail.
In the related art, since the security algorithm fallback process is wrongly performed in the process of radio link re-establishment, thereby it results in the problems of radio link re-establishment failure and a low success rate of the radio link re-establishment.

Method and apparatus for re-establishing radio link


Display device integration techniques and structures are disclosed that improve display performance, usability, and reduce system cost. The improved designs and techniques involve direct view display devices, pen/stylus input devices, Integrated Circuit (IC) driver units (74), backlight devices (41) and fiberoptic faceplates (3, 6). The types of display devices, included in the inventions, may involve Cathode Ray Tube (CRT) displays, Liquid Crystal Displays (LCD), as well as other type of displays, including flat panel displays. The pen/stylus input device consists of a pen/stylus (5), a sensor/emitter film (4), and pen encoding electronics (20). One or more fiberoptic faceplates may be included. The inside surface of the fiberoptic faceplate may be reticulated, having reflective structures (28) and phosphor dots (12) applied. Distributed Index planar micro lens arrays may be incorporated instead of fiberoptic faceplates. The backlight device may include several light sources (41A, 41B), a fiber backplate (45) and several pig tail regions (56, 58). A new micro tip semiconductor tunneling technology is disclosed for the interconnection of two or more IC units or display sub-panels, without actual physical conductor-to-conductor contact.

The prior art in the field of flat panel display devices includes: Liquid Crystal Displays (LCD), Cathode Ray Tube (CRT) displays, pen/stylus input screen means, and fiberoptic faceplates. There is a great amount of prior art in LCD and CRT devices and systems. There is a fair amount of prior art in pen or stylus position input encoding means, which is defined as apparatus used to determine (encode) the position of a stylus or pen as it is moved over an area by the hand of a person. Thus, when a person writes, draws or sketches onto or over and an active area, a signal is generated representing its position repeatedly as the pen is moved. Typically, these devices make use of a electromagnetic sensors or emitters that either cover the front of a display screen or placed behind the screen. Prior art combinations of pen input devices with display devices include U.S. Pat. No. 4,361,725 of Dagnelie, which discloses a CRT with a roughly transparent grid placed onto a conventional CRT glass faceplate. Prior art in the combination of touch panels to a displays include Japanese Patent 59-184925 of Sugiyama, which discloses a touch screen placed over a CRT. U.S. Pat. No. 4,911,536 of Ditzik discloses a graphic tablet encoding means placed over an projection screen of a non-direct view projection display device. Each of these prior art combinations suffer from several shortcomings, such as the parallax effect, large number of parts, and/or high cost.
Prior art in fiberoptic (FO) faceplates involve placing them onto display devices for the purpose of optical coupling the display screen to an optical system, or using them in high brightness direct view displays. CRTs have been manufactured with fiberoptic plates, which focuses and relays the image from the CRT to a light valve or large screen projection system. U.S. Pat. No. 4,591,232 of Jeskey disclosed fiberoptic CRT faceplates that have light absorbing black fibers dispersed throughout the bundle to reduce "halation" or "ballooning" of the image. U.S. Pat. No. 4,573,082 of Jeskey disclosed a similar CRT fiberoptic faceplate for optical transfer of an enhanced image to a projection screen. In addition, European Patent 0122829 of Rover et. al. disclosed a fiberplate to act as an optical filter in order to provide optimum visibility of a display device under a variety of ambient viewing conditions. The primary shortcoming of the these piror art display devices is that they do not disclose or anticipate pen/stylus input means integrated with a display. This puts such display devices at a severe disadvantage in the highly interactive computer, display, and PDA markets.
There is prior art in placing stylus digitizers onto display devices. For example, U.S. Pat. No. 3,671,668 of Reiffel discloses a CRT having a standard glass faceplate with a transparent spatial signal generator placed onto it and separated by an air gap. U.S. Pat. No. 4,723,836 of Kono and Inoue disclosed an electromagnetic opaque digitizer tablet placed behind a LCD panel. However, in each of these cases, there exists a top glass substrate, a polarizer and other components between the display image and the viewer's eyes. The thickness of these components causes an undesirable effect of parallax. The parallax effect is defined as the viewable gap or distance between the pen/stylus tip placed onto the screen and the actual viewed image. The above display devices and pen/stylus input device combinations have parallax. This is very annoying and objectionable effect to the user who is trying to write or draw onto the display screen. It is especially a problem with CRT displays, which may have faceplates roughly 0.5-0.85 inch thick.
U.S. Pat. No. 4,873,398 of Hubby discloses means to reduce the parallax effect by introducing a lens or lens arrays placed between a LCD panel and a transparent digitizer means. Hubby's lens or array projects the image from the display through the digitizer plate to a separate rear projection screen. This may reduce the parallax effect somewhat, but it has several shortcomings. First, the lens array will have significant light loss from lens to lens cross transmission. This will cause a low contrast image. Secondly, the disclosed projection screen must have a thickness; therefore, the screen itself will cause some parallax. Finally, with the prior art components, the displayed image will be distorted by digitizer layer and lens array layers. U.S. Pat. No. 4,943,348 of Ibamoto et al disclose two or more micro lens arrays placed between a LCD and a protective glass or pen tablet means. However, Ibamoto's arrangement introduces unnecessary complexity by having two or more lens arrays to register with respect to each other, for providing an erect image. Ibamoto's fails to realize that an erect image on a pixel bases is not necessary in display devices. The above embodiments suffer from an overly complex design with a high parts count and high associated cost.
Besides the parallax effect, another shortcoming of prior art display devices and pen display combinations is optical glare from the front surface of the screen. Prior art solutions for screen glare involve special coating(s) or frosting the front surface. A disadvantage of placing anti-glare optical coatings onto a display screen is that it adds significant cost to the display. Both of the above anti-glare techniques cause some degradation of the displayed image, due to light scattering and light absorption of the material. These image degradation effects are caused by the various coatings, plates or films placed between the image material (LC or phosphor) and the user's eyes. These shortcoming cause serious ergonomic problems, especially when a person is trying to point, write and/or draw onto the display screen.
The inventions of the applicant overcomes each of the above prior art shortcomings and disadvantages by tightly integrating one or more fiberoptic faceplates to a direct view display device. A first faceplate may be manufactured as a part of the display device. A second faceplate may form a substrate for a pen/stylus input sensor/emitter means. When the second faceplate is placed against the first with very little or no gap, the two faceplates will appear as one plate, of zero thickness, to the viewer. This embodiment will virtually eliminate any parallax effect for the viewer. In addition, there will be less front surface glare and a wider viewing angle. In LCD display panels, a fiberoptic faceplate will provide for a brighter image in darken ambient room lighting conditions. These advantages over the prior art will insure a wider acceptance of the display device in the highly interactive computer, communications, and entertainment markets.
Certain flat panel display devices, such as Liquid Crystal Displays (LCD), may require a backlight for better viewability. A number a backlight technologies are known to provide a relatively uniform light to the back of display panels. Prior art in backlights include electro luminescent, fluorescent, incandescent, and LED light sources. A number of light guide devices have been used to apply light to the rear of the display panel, using various fiber, glass, and plastic optical guides. However, several problems arise when the display must be viewed under sunlight, twilight, or night conditions. Each of these viewing conditions require different backlighting designs. The new multiple backlight invention described herein solves these problems by providing a simple way of using multiple light sources and integrating their light to the rear of an LCD panel.

Direct view display device integration techniques


The dynamic DC offset canceling apparatus includes: section 104 that detects dynamic DC offset in longest overlapping part sequences from the differences between the sampling values of a first longest overlapping part sequence and the sampling values of a second longest overlapping part sequence, the first longest overlapping part sequence and the second longest overlapping part sequence being overlapping part sequences in a training sequence of the received signal; section 105 that detects dynamic DC offset outside the longest overlapping part sequences from the difference between an average value of sampling values of a received signal which exists in a burst before the first longest overlapping part sequence, and an average value of sampling values of a received signal which exists in a burst after the second longest overlapping part sequence; and section 106 that adaptively subtracts a DC offset value from the received signal based on these results.

1. Field of the Invention
The present invention relates to a dynamic DC offset canceling apparatus and a dynamic DC offset canceling method for a receiver in wireless communication, and primarily relates to a dynamic DC offset canceling apparatus and a dynamic DC offset canceling method used in the receiver having a radio section adopting the direct conversion scheme in digital mobile communication.
2. Description of Related Art
The receiver in digital mobile communication receives radio waves from a plurality of paths with different propagation times, due to the influence of multipath fading which may occur in a radio link. Therefore, delay distortion is produced in the received signal and bit error rate characteristics deteriorate. Faster symbol rates produce larger delay distortion, and so with future high-speed digital mobile communication equipment, the influence of delay distortion cannot be ignored, and cancellation of delay distortion becomes essential.
An equalizer is a typical means for correcting delay distortion. In radio communication, conventionally, equalizers are mounted on receivers that perform high-speed transmission, and, further, in recent years, equalizers are mounted on mobile telephones and the like adopting GSM (Global System for Mobile Communications), which is the European digital mobile telephone standard. Further, there is an increase in the number of receivers that improve equalization accuracy and improve bit error rate characteristics by estimating the DC offset component, which may be mainly produced in a radio RF section, using an average value of the received signal and canceling the DC offset component as preprocessing of the equalizer.
FIG. 11 is a block diagram showing the configuration of a receiver with a conventional DC offset canceling apparatus, and FIG. 12 shows the configuration of a DC offset compensating processing section in the receiver. In FIG. 11 and FIG. 12, receiver 10 with the DC offset canceling apparatus is configured with DC offset compensating processing section 11, equalizing processing section 12 and decoding processing section 13, and DC offset compensating processing section 11 is configured with average value calculating section 14 and DC offset canceling section 15. In DC offset compensating processing section 11, average value calculating section 14 estimates a DC offset component using an average value of the received signals, and DC offset canceling section 15 cancels the DC offset component.
In recent years, to reduce the circuit scale (cost) of the radio RF section, the direct conversion reception scheme is adopted instead of the heterodyne reception scheme which converts a received frequency to an intermediate frequency. However, to accompany the spread of the direct conversion reception scheme, in the narrow band digital modulation scheme used in GSM and the like, the received signal frequency is equal to a local frequency, and so the DC offset component remains in a detection output of the receiver (baseband received signal), and, in particular in GSM, DC offset (hereinafter "dynamic DC offset") increases rapidly in the middle of the burst, and, as a result, DC offset may become difficult to cancel by estimating an average value of the received signals, which may result in deterioration of bit error rate characteristics. Further, in GSM, known codes (training sequence) for acquiring synchronization and assisting reception are embedded in the middle of the burst, and dynamic DC offset in the middle of the burst deteriorates bit error rate characteristics significantly.
To cancel dynamic DC offset, with the conventional DC offset canceling algorithm, digital baseband signals are mapped on an IQ diagram, and the I and Q coordinates of the center point are determined by two-dimensional fitting of a geometric figure using a subset of signal values. It is possible to learn changes with dynamic DC offset from changes of the center point (see, for example, Patent Document 1: Japanese Patent Application Laid-Open No. 2000-278335).
However, a problem with such a conventional DC offset canceling apparatus is that calculation for determining the center point for an arbitrary consecutive subset of digital baseband signals increases the amount of processing.

Dynamic DC offset canceling apparatus and dynamic DC offset canceling method


An ink jet printer having an improved print head cleaning apparatus includes an ink cartridge provided with a print head on a lower portion thereof and performs a linear reciprocating movement in a predetermined direction by means of a carriage. A housing is disposed below a lower side of the carriage. A wiper is provided in the housing and cleans the print head in contact with the print head. A wiper variable position unit moves the wiper to change a contact position between the print head and the wiper.

1. Field of the Invention
The present invention relates to an ink jet printer with an improved print head cleaning apparatus and method of operating the same. More particularly, the present invention relates to an ink jet printer with an improved print head cleaning apparatus and method of operating the same, in which a contact position between a print head and a wiper is periodically changed, thereby preventing abrasion of the wiper and enhancing a wiping effect of the wiper.
2. Description of the Related Art
As a general rule, ink jet printers are designed so that a carriage with an ink cartridge is movably installed to a main frame. The carriage is reciprocated by a moving unit, with support on a timing belt and a guide shaft.
The ink cartridge is provided with a print head on a lower side thereof. The print head sprays ink on printing paper fed by a feeding roller, thereby generating an image. The print head sprays the ink on one side of the printing paper through an injection nozzle, and thus the ink transferred into the printing paper forms an image. Operation of spraying the ink through the injection nozzle is appropriately controlled according to image information received at a controller of the printer.
After printing, residual ink is found in the injection nozzle. Sometimes, especially after the printer has been idle for a long time, the residual ink in the injection nozzle becomes solidified. In this case, the injection nozzle is entirely or partly clogged by the solidified ink. As a result, a proper amount of ink is not sprayed during printing, which results in poor print quality.
The ink injection nozzle may be clogged by the ink as well as by a foreign material such as dust. Dust will also negatively affect print quality. Therefore, to prevent the ink injection nozzle from being clogged, a device for cleaning the print head is required.
Such a print head cleaning apparatus is disclosed in Japan Patent Publication No. 2001-18407 (publication date: Jan. 23, 2001; title: INK JET PRINTER), the entire contents of which are incorporated herein by reference.
As for its configuration, a nozzle head wiper holding member is mounted to a wiper carrier capable of reciprocating in the main scanning direction of a nozzle head in such a manner that the nozzle head wiper holding member can be vertically moved through a predetermined range. A spring for upwardly urging the nozzle head wiper holding member is provided between the wiper carrier and the nozzle head wiper holding member. Both elastically deformable nozzle head wipers, and a wiper contact angle adjusting roller rotatably engaged with the nozzle head side are attached to the nozzle head wiper holding member. The nozzle head is capable of being wiped by holding a contact angle of each of the nozzle head wipers with respect to the lower surface of the nozzle head to a constant level.
One example of the conventional print head cleaning apparatus is shown in FIG. 1. As shown, the device includes a housing 10 installed on the lower side of a cartridge 1, a plate 11 slidably mounted in the housing 10, and a wiper 13 vertically provided on the plate 11. The wiper 13 cleans a print head of the ink cartridge at a home position while it is reciprocated by the plate 11.
The conventional print head cleaning apparatus brings the print head into contact with the wiper at a single position at all times. For this reason, the wiper is subjected to concentrated abrasion at only that single position, thus decreasing wiping efficiency.

Ink jet printer with improved print head cleaning apparatus and method of operating the same


A shape-memory polymers comprising at least one monomer subunit represented by the following structural formula (1).

Shape memory alloys, such as TiNi alloys, have been applied widely in medical fields (e.g. as a urethra arterial stent for enlarged prostate) due to their unique shape memory effect, high strength and excellent biocompatibility. However, these alloys show some obvious disadvantages, such as high manufacturing cost, limited recoverable deformation and lack of biodegradability.
Recently, biodegradable shape-memory polymers (SMPs) have attracted much attention and several kinds of biodegradable polymers have been reported. Specifically, SMPs can be produced from different natural or synthetic raw polymers, such as chitosan, cellulose, polyetherurethanes, poly(ε-caprolactone). The synthesis and post treatment methods of the polymers were complicated and the mechanical properties are insufficient for various biomedical applications.


An endoprosthetic implant is formed from a plurality of separate individual components that are inserted sequentially and transluminally into a bifurcated vascular region with each component being deployed in sequence by a sequence of catheter-like deployment devices. The separate components are placed relative to each other to define a bifurcated endoprosthesis. In one embodiment the deployment device includes a tubular sheath for maintaining the radially expandable tubular implant in a contracted configuration and a gripping device including a cup and a gripping member that cooperate to define an annular space by which the trailing end of the implant can be securely held by the deployment device during positioning of the device.

Among the long accepted practices to treat a variety of vascular disorders are surgical procedures that involve placement of a tubular graft in a patient's blood vessels. The construction and characteristics of the graft typically are adapted to optimize its use in the specific surgical environment and condition to be treated and, accordingly, a number of different types of grafts are available. Among the most common vascular grafts are those formed from a woven or knitted tubular fabric as well as non-fabric tubes such as expanded polytetrafluoroethylene. Such grafts typically are placed in a patient's vascular system in a highly invasive surgical procedure. In general, the complexity of the surgical procedure required to place the graft will depend on many factors, including the location and surgical accessibility of the portion of the patient's vasculature where the graft is to be placed.
Not all vascular conditions in which it would be desirable to place a graft can be so treated. Among the particularly troublesome medical conditions in which it is desirable to place a graft is that of an abdominal aortic aneurysm, in which a portion of the patient's aorta, the major artery carrying blood from the heart, has developed a weakened wall such that the weakened portion will tend to expand under the influence of the patient's blood pressure. An aortic aneurysm presents a life threatening risk that the aneurysm may burst causing massive internal bleeding. Treatment of the condition typically has involved deeply invasive abdominal surgery in which the patient's abdominal cavity is opened to reach and expose the aortic aneurysm. While maintaining the patient on an independent life support system, the region of the aneurysm is incised lengthwise to enable insertion of the graft into the aorta to span the weakened region and define a structurally strong tubular flow path between the remaining healthy portions of the aorta. The graft, so positioned, then is sutured in place. The graft thus serves as a reinforcing liner for the weakened portion of the aorta. Such surgical procedures have been characterized by a relatively high mortality rate. Typically, patients suffering from the condition are elderly and are less able to survive the rigors of major abdominal surgery. Additionally, there is a substantial degree of risk when the abdominal cavity is opened because the confining pressure of other abdominal organs on the aorta is released. In some cases, the aortic wall in the region of the aneurysm is so weak that upon release of the confining pressure, the aneurysm may burst with resulting immediate massive hemorrhaging.
Significant effort has been directed to the development of less invasive techniques for placement of a graft, such as in the abdominal aortic region, in a manner that presents less risk to the patient. Various devices in the form of a single tubular implant have been described for that purpose. Typically, such single tube devices have a means for anchoring the ends of the graft to healthy vascular tissue at the opposite ends of the aneurysmal region.
In the case of abdominal aortic aneurysms, however, by the time the aneurysm is discovered, it may have advanced to a stage where there is insufficient healthy tissue in the region where the aorta bifurcates into the two iliac arteries for the end of a single tubular graft to be secured. Often the aneurysm has advanced into and involves the iliac arteries as well. Such a condition cannot be treated by a single lumen tubular prosthesis. If an endoluminal prosthesis is to be placed in such anatomy, the prosthesis must have a bifurcated configuration in order to extend fully through the regions of aneurysm in all of the involved arteries and with the device being in secure engagement with healthy tissue to insure that it provides full endoluminal support and will not migrate from its implanted position.
The necessity for the use of a bifurcated graft has been recognized. One approach is described in U.S. Pat. No. 5,489,295 (Piplani) in which a one-piece bifurcated graft is described as being placed in the bifurcated region of the aorta and iliac arteries. The procedure described is complex and requires many difficult manipulations by the physician. Additionally, the unpredictable variations and vascular anatomy of an individual patient can be expected to present blood vessels of shapes and diameters that do not readily match the preformed configuration of a one piece, preformed, bifurcated graft. Consequently, the use of such a graft is likely to result in mismatches between one or more of the three legs of the bifurcated graft with the corresponding aorta and iliac arteries.
Another device is described in PCT patent application PCT/US95/01466 (International Publication No. WO95/21592) in which a bifurcated device is formed in two sections, one of which includes a graft having a main body and one integral leg extension. The main body is intended to be placed in the aorta and the extension in one of iliac arteries. The main body also has an opening adjacent the leg extension that can be aligned with the other iliac artery. The second section of the device includes a tubular graft that can be advanced through the other iliac artery into engagement with the opening in the main body. This arrangement also is awkward to place and presents additional difficulties. Among those difficulties is that where the body and one of the legs is formed in a unitary structure, the device similarly does not lend itself to modular construction in which the individual components can be combined to match the dimensions of the particular patient's anatomy. Also among the difficulties with the device is that it employs stenting elements formed from a shape memory alloy that is not readily visualized under fluoroscopic examination and must be placed relatively quickly, before the stent expands as a consequence of exposure to body temperature.
A third approach, described in PCT application PCT/DK94/00468 (International Publication No. WO95/16406) employs an endovascular device for placement at the region of an arterial bifurcation that includes a three-component system including a main, bag-like body intended for placement in the aorta. The bag-like body has a pair of openings formed at its lower end. Each of the openings is said to receive an end of a tubular prosthesis inserted through each of the iliac arteries. The tubular prostheses are said to attach to the main bag-like body and extend into the iliac arteries. Among the apparent difficulties with this arrangement are that there is no way for the physician to visualize, fluoroscopically, the main bag-like body or the location of the openings that must be accessed in order to insert the leg segments into the openings. Additionally, the apparently flexible structure of the bag-like body would enable the bag to flex under the influence of blood flow, body movement and engagement with the apparatus for delivering and placing the leg segments, all of which would present considerable difficulties in the placement process. Moreover, even if the leg segments could be attached to the main body, the apparent relationship of the leg segments with the main body is such as to present an irregular, turbulent flow path from the main body to the leg extensions.
None of the prior art relating to the placement of a bifurcated tubular endoprosthetic implant within the region of the aortic-iliac arteries has suggested a modular construction by which the components can be accurately positioned, assembled and, if necessary, is recaptured within the delivery device so that the module can be redeployed in its proper position or removed in its entirety. Additionally, none embodies an arrangement in which the leg portions of the stent have a high degree of flexibility in order to conform easily to the configuration of the particular patient's vascular anatomy.
It would be desirable to provide a modular implant that can be constructed in situ with modules that can be accurately placed and connected easily with individual modules selected to conform closely to the vascular anatomy of the individual patient. It is among the general objects of the invention to provide such a modular implant construction.

Deployment device for tubular expandable prosthesis


An optical disk apparatus for forming an image on an optical disk according to dot data which defines density of dots of the image, the optical disk apparatus includes: a framing unit which makes a frame data by grouping a plurality of unit data, wherein when the dot data, the dot data are treated as the unit data; a pit forming unit which sequentially forms pits defined by a bit train signal of the frame data; a discrimination unit which determines whether the section in the frame data corresponding to the dot data is a predetermined value; and a gate unit which, in case the discrimination result by the discrimination unit is affirmative, supplies the bit train signal to the pit forming unit and, in case the discrimination result by the discrimination unit is negative, interrupts supply of the bit train signal to the pit forming unit.

The present invention relates to an optical disk apparatus having a function of recording data onto an optical disk as well as a function of forming an image.
Some of the optical disk apparatuss available in recent years have an image forming function of forming an image of a character or a figure in addition to a recording function of recording data such as audio data onto an optical disk including a CD-R (Compact Disc-Recordable) (for example, refer to the Japanese Patent Laid-Open No. 7530/1996). This type of optical disk apparatus irradiates with laser light a recording surface on which data is recorded to change the color of part of the recording surface by means of heat, thereby forming an image of a character or a figure.
The image forming feature incorporated into an optical disk apparatus leads to a more complicated design of the optical disk apparatus, which results in an increase in device cost. A longer time required to form an image onto an optical disk or poor picture quality will impair the added value.

Optical disk apparatus and computer readable recording medium storing program


Information is transmitted in digital form over fading channels using DPSK coded modulation incorporating multi-level coding in order to provide unequal error protection for different classes of data such as generated by CELP or other speech encoders.

The present invention relates to the transmission of information in digital form over fading channels.
The increasing prominence of wireless telecommunications--particularly in the realm of digital cellular mobile radio--has given rise to the demand for improvements in the bandwidth efficiency of such systems. To this end, efficient coded modulation schemes, such as the built-in time-diversity technique disclosed in U.S. Pat. No. 5,029,185, issued to L. F. Wei on Jul. 2, 1991 and entitled "Coded Modulation for Mobile Radio," have been developed. Increased bandwidth efficiency is also achieved in these systems via the use of low-bit-rate speech coders, such as the so-called code-excited linear predictive (CELP) coders, which operate in the range of about 4 to 8 kilobits per second (kbps).
The low-bit-rate coders represent speech information in such a way that certain aspects of the coded information is of significantly greater importance than other aspects in terms of being able to recover intelligible speech at the receiver. In CELP coders, for example, that so-called "important information" may comprise a) the linear predictive coding (LPC) parameters, b) the pitch, and c) a bit of information which indicates whether the speech was voiced or unvoiced. It is thus desirable that the transmission scheme be able to communicate the "important information" with a high degree of reliability, even at the expense--if channel conditions make it necessary--of the other, "less important" information. Such transmission schemes are referred to herein generically as schemes which provide "unequal error protection." And it should also be noted at this point that, in general, there can be any desired number of classes of information, of varying importance, rather than being limited to, for example, two classes.
Transmission schemes which provide unequal error protection are, in fact, known in the prior art. Such known technology is exemplified by, for example, in Carl-Erik Sundberg, "Optimum Weighted PCM for Speech Signals," IEEE Transactions on Communications, Vol. COM-26, No. 6, June 1978, pp. 872-881; C.-E. W. Sundberg et al., "Logarithmic PCM weighted QAM transmission over Gaussian and Rayleigh fading channels," IEE Proceedings, Vol. 134, Pt. F, No. 6, October 1987, pp. 557-570; and in the commonly assigned co-pending patent applications of V. B. Lawrence et al., Ser. No. 07/611,225 filed Nov. 7, 1990 (now U.S. Pat. No. 5,164,963, issued Nov. 17, 1992) and entitled "Coding for Digital Transmission," and of L. F. Wei, Ser. No. 07/611,200 filed Nov. 7, 1990 (now U.S. Pat. No. 5,105,442, issued Apr. 14, 1992) and entitled "Coded Modulation with Unequal Error Protection." Wireless telecommunications of the type that the present invention is concerned with are typically carried out over so-called fading channels, by which is meant so-called Rayleigh or near-Rayleigh channels, where multiplicative Rayleigh noise is the predominant noise phenomenon. However, the prior art (for coded modulation) has generally addressed the unequal error protection problem in the context of transmission of the information over, for example, voiceband telephone channels and HDTV channels, where additive white Gaussian noise is the predominant noise phenomenon, and those schemes will not perform effectively if used for the fading environment. Moreover, although aforementioned coded modulation schemes as disclosed in the Wei patent application are, in fact, directed to fading channel applications, they provide equal error protection for the transmitted data rather than the unequal error protection that is so highly desirable for the aforementioned coded speech applications. It can also be noted that schemes which provide unequal error protection in conjunction with binary and quaternary phase shift keyed signals are known in the prior art. See "Rate-compatible punctured convolutional codes for digital mobile radio," by J. Hagenauer, N. Seshadri and C.-E. W. Sundberg in IEEE Transactions on Communications, Vol. 37, No. 7, July 1990. However, these schemes are limited to a maximum of two bits per symbol, irrespective of the signal-to-noise ratio (SNR) of the channel and are thus bandwidth-inefficient. Moreover, even when achieving two bits per symbol, these schemes are power-inefficient.
There thus remains in the art the need for effective, bandwidth- and power-efficient transmission schemes which can provide unequal error protection in fading channel environments.

Coded modulation with unequal error protection for fading channels


A head slider to which little amount of contaminants is adhered, that can form a uniform and flat head lubricant layer surface and that has excellent ultra-low floating properties, as well as a magnetic recording device equipped with the head slider are provided. The head slider is equipped with a head slider lubricant layer having an average film thickness of not more than 2.5 nm, and composed of a water-repellent resin, the lubricant layer being formed on the head slider surface and head slider protection layer surface facing the magnetic recording medium, and the surface tension of the head slider lubricant layer determined by the Fowkes equation is not more than those of the head slider surface and head slider protection layer surface.

1. Field of the Invention
The present invention relates to a head slider of a magnetic recording device.
2. Description of the Related Art
In a magnetic recording device, a head slider equipped with a record transducer (also simply referred to as "head" in the present invention) reads and writes information, while floating over a hard disk or a magnetic recording medium.
The distance between the head and a magnetic layer that records (writes) and/or reproduces (reads) magnetic information on the hard disk, is called a magnetic spacing. The smaller the magnetic spacing is, the more improved the recording density is. Accordingly, the present level of the floating gap for a head has become as small as 10 nm or less as a result of a strong need for higher recording density in recent years. In such an ultra-small floating gap, only a small amount of contaminants adhered onto a head slider may make the floating stability of the head greatly out of balance.
Volatile organic materials, debris. etc. brought about from the environment are examples of such contaminants. As the head slider moves, volatile organic materials, debris. etc. adhered to the hard disk are scraped together and collected on the head slider, and eventually fill in the head floating gap, resulting in head crashing.
Various methods are suggested to solve the problem described above. For example, a method is proposed to restrain adhesion of contaminants by providing a head slider surface that faces a magnetic recording medium (also simply referred to as "head slider surface" in the present specification) with patterning so as to decrease the surface energy (see Japanese Unexamined Patent Application Publication No. H09-219077). However, this method has a disadvantage that a high production cost is inevitable for the manufacturing of head sliders.
Also, a method is suggested in which a self-assembled membrane is formed on the head slider surface to decrease the surface energy (see, for example, Unexamined Patent Application Publication No. H11-16313). However, the film thickness of the self-assembled membrane (or the length of a molecular chain) is rather large, requiring wide magnetic spacing. Accordingly, this is not suitable for a higher recording density. Furthermore, the self-assembled membrane employed in this method comprises silicon that is known as a substance that tends to bring about head crashing. This also makes a drawback against the practical application.
Furthermore, it is proposed to decrease the adhesion of contaminants by applying a lubricant that is the same as or resembles to a lubricant applied to a hard disk, onto the head slider surface and the surface of a head slider protection layer (also referred to as "head protection layer" in the present specification), followed by UV-ray irradiation so as to lower the surface energy (see Japanese Unexamined Patent Application Publication No. H07-85438, for example). However, this method is disadvantageous in the following point. It is known in general that the lubricant is transferred from the disk surface to the head slider surface side by means of evaporation from the disk and intermittent contact with the head slider, etc., with the result that a film as thick as the lubricant layer on the disk is formed on the outermost head slider surface facing the disk (also referred to as "ABS" that is an abbreviation of "air bearing surface"). In a device having a sufficiently wide floating gap, such lubricants adhered to the ABS have been posing little problem. However, as the floating gap has been made smaller, it has come to be generally known that this behavior makes the floating of the head unstable. It is understood that the floating is obstructed by the lubricant on the ABS contacting with the disk, and forming a liquid bridge.
One advantage of this method is that the liquid lubricant layer is made into a solid form by fixing the lubricant applied to the head slider by means of UV ray irradiation, thus leaving the liquid bridging less liable to occur. However, simple application of such a lubricant having a polar molecular end group as disclosed in Japanese Unexamined Patent Application Publication No. H07-85438 will incur coagulation of the lubricant due to its cohesive force, and accordingly, not only solidifying of the lubricant with UV ray irradiation will result in uneven coating but also the height of the coagulated lubricant occupies a substantial portion of the floating gap, sometimes resulting in floating problems such as failure of floating of the head slider, head crashing, scratching of the magnetic recording medium, etc. Also, depending on the level of UV ray irradiation, part of the head slider lubricant layer (also referred to as "head lubricant layer" in the present invention) may exist as a liquid. Such part will still cause liquid bridging, letting down the expected effect.
As described above, it is difficult to achieve both of reduction of adhered contaminants to a head slider and ultra-low floating properties of the head slider. There is also a problem of coagulation of a resin that forms the head lubricant layer. Accordingly, there is a need for solving these problems. It is an object of the present invention to solve these problems, and provide technologies that can achieve reduction of adhered contaminants on a head slider, prevention of coagulation of a resin for forming the head lubricant layer, and ultra-low floating properties of the head slider. Other objects and advantages of the present invention will be clarified through the following explanation.

Magnetic recording device having a head slider utilizing a water-repellant resin lubricant having specified surface tension properties