A display includes connection lines each of which is provided for the corresponding scanning line of the display and is connected to a light emission element driving circuit, a ramp voltage generating section for generating ramp voltage for varying the control electrode voltage of each of the driver transistors relative to the voltage of the other electrode of the corresponding driver transistor to change the emission state of the corresponding light emission element, and a ramp voltage driver for supplying the ramp voltage to each of the connection lines provided for the corresponding scanning line in response to the scanning.

1. Field of the Invention
The present invention relates to a display apparatus including active elements for driving light emission elements such as EL (electroluminescent) elements and LEDs (light emission diodes) and its driving method, and more particularly to a display apparatus including thin film transistors (TFTs) as active elements and the driving method therefor.
2. Description of the Related Art
TFTs are widely used as active elements for driving an active matrix display such as an organic EL display and a liquid crystal display. FIG. 1 shows a pixel PLi,j in an example of an equivalent circuit of a driving circuit in an organic EL (organic electroluminescent) element (OEL) or an organic light emission diode (OLED) 100.
As illustrated in FIG. 1, the equivalent circuit includes two p-channel TFTs 101 and 102 as active elements and a capacitor (Cs) 104. A scanning line Ws is connected to the gate of the selector TFT 101. A data line Wd is connected to the source of the selector TFT 101. A power supply line Wz for supplying constant supply voltage Vdd is connected to the source of the driver TFT 102. The drain of the selector TFT 101 is connected to the gate of the driver TFT 102. The capacitor 104 is provided between the gate and the source of the driver TFT 102. The anode of the OEL 100 is connected to the drain of the driver TFT 102, and the cathode of the OEL 100 is connected to the ground voltage (or common voltage).
When a selecting pulse is applied to the scanning line Ws, the selector TFT 101 as a switch is turned on and the selector TFT 101 becomes conductive across its source and drain. Simultaneously, data voltage is supplied through the connection between the source and drain of the selector TFT 101 from the data line Wd and accumulated in the capacitor 104. The data voltage accumulated in the capacitor 104 is applied between the gate and source of the driver TFT 102. As a result, drain current Id corresponding to gate-source voltage Vgs of the driver TFT 102 is generated and supplied to the OEL 100, and the OEL 100 having received the drain current Id emits light.
The active matrix display having this structure displays images by supplying data signals corresponding to input video data to the respective pixels PLi,j via the data lines while sequentially applying selecting pulses (scanning pulses) to the respective scanning lines.
However, the known active matrix display holds display data for a period of one frame. This type of display is referred to as a hold-type display apparatus.
When the display continues image display while holding the display data for the frame period, the image display quality, particularly the image display quality of the moving images display, is deteriorated. That is, contours of images are blurred and recognized as blurred images, or false contour noise is generated.
For overcoming these drawbacks, for example, Japanese Patent Applications Kokai No. 2003-223136 and No. 2003-5709 disclose structures for stopping light emission from light emission elements for a predetermined time in a frame period.

Active matrix display apparatus and driving method therefor


A method and apparatus are disclosed for browsing one or more Management Information Base (MIB) objects that are stored in a network device, such as a router or switch. In one embodiment, the network device receives a connection of a Web browser at an HTTP daemon and further receives a request from the Web browser to obtain the current value of the MIB variable. The request may be sent in a Hypertext Transfer Protocol (HTTP). The HTTP daemon passes the request to an HTTP-SNMP interface. The HTTP-SNMP interface creates an SNMP query for the current value of the MIB variable and sends the query to an SNMP daemon of the network device. The SNMP daemon obtains the current value of the variable from a MIB of the network device. The network device then returns the current value of the MIB variable to the Web browser which can display it.

Computer networks consisting of end stations, routers, hubs, switches, gateways, firewalls, and other network devices are in widespread use. Management and support issues are perhaps the most difficult issues to grapple with in networked computing. The upside is that the benefits of networks are real—lower hardware and software costs, more flexible systems, easier to use front-ends. Unfortunately, administration and support is more costly than for centralized systems. Networked computing often disperses network devices across a wide geographic area and creates time-consuming problems for network administrators concerned with keeping these systems running.
Several conventional standards are available to administrators for managing networks and systems. One such standard is Simple Network Management Protocol (SNMP), which is currently the most widely implemented protocol for management of network devices such as routers, hubs and switches. SNMP performs relatively simple management of the components in a network. SNMP uses object-oriented techniques to describe the information to be managed. Each piece of information to be managed is called a managed object. The managed objects can represent anything that needs to be managed, for example, an entire host, a program, or a variable maintaining a counter of Transmission Control Protocol (TCP) packets.
A Management Information Base (MIB) defines a structured collection of the managed objects. This structured collection of managed objects is commonly referred to as a MIB tree, which is a hierarchical data base with names and variables for each object component within the tree. Objects are defined by their hierarchical location in the MIB tree. For example, the IP object group is defined by the location value 18.104.22.168.2.1.4. This number is referred to as a MIB variable. A new object and its corresponding MIB variable is always added in the tree "down and to the right." SNMP is the protocol used to set values and retrieve values of MIB variables.
FIG. 1 shows a conventional network system. A local area network (LAN) 103 is protected from a separate public or untrusted network 100 by a firewall 102, which is a gateway device that is configured or programmed to control access to network 103 of devices coupled to network 100. The network 100 may be, for example, the global, packet-switched internetwork known as the Internet, a wide area network (WAN), etc.
LAN 103 includes one or more network devices 106, 108. Each network device is a router, switch, hub, etc., that is coupled to one or more servers, printers, workstations, personal computers, or other end station devices. There may be multiple LANs 103 connected to the Network 100. Although FIG. 1 depicts only two network devices 106, 108 in a practical system there may be hundreds or thousands of network devices, distributed over a wide geographic area, and many network management systems 104.
A MIB 110 is stored in and managed by each of the network devices 106, 108. Each MIB 110 stores values of MIB variables that pertain to the associated network device 106, 108.
A network management system (NMS) 104 manages the network devices 106, 108 by, among other things, collecting information from the MIBs 110, processing the MIB information, and presenting it to a user or display device. As mentioned above, SNMP is typically the protocol for doing such managing. NMS 104 comprises one or more software program elements that manage one or more local databases of network management information. An example of a commercial product that is suitable for use as NMS 104 is Resource Manager Essentials, commercially available from Cisco Systems, Inc., San Jose, Calif.
As an example of NMS processing, a MIB engine in the NMS provides active background daemons that monitor current values of network device MIB variables as compared to historical data in order to identify trends and unusual developments in the network devices. From the NMS, triggers can be used to launch corrective actions in the network devices 106, 108. Since a portion of the management data is maintained by the network devices themselves and stored in the MIBs, data of interest may be spread on MIBs 110 throughout the network system. The NMS 104 maintains aggregate snapshots of this distributed data. However, the data stored by the NMS 104 is not as up-to-date as the data in the MIBs.
The primary value of SNMP comes from the MIB data it manages. In practice, the primary value of SNMP comes from the ability to navigate through MIB trees and to understand the MIB vocabularies. Unfortunately, there is nothing simple about MIBs or their arcane vocabularies. MIBs are not very human-friendly as they have been designed to be used by applications.
Moreover, MIBs are typically accessible by humans only through NMS terminals, which are not always convenient for administrators. The conventional NMS features do not provide human-friendly tools for accessing MIB variables. NMS tools, for example, typically do not present to the network administrator the MIB variables in an organized format, such as a MIB tree, which was discussed above. Only the most experienced network administrators can make sense of the multitude of MIB variables within a MIB. In other cases, NMS functions that retrieve and set values of MIB variables are embedded in the NMS software and cannot be used to selectively retrieve values of MIB variables that interest a particular user.
Thus, there is a need for a method and apparatus that makes objects in MIB trees more accessible to human users. More specifically, there is a need for tools to make MIBs more accessible and thereby reduce the number of costly problems that administrators must deal with on a daily basis in keeping their network systems running.
In particular, there is a need for a method and apparatus that enables a human user to view values of MIB variables through means other than a network management system.

Method and apparatus for browsing a management information base


An electronic device includes a keypad and a sensor that indicates proximity of a user to the electronic device, whereupon the keys of the keypad are illuminated. In particular, when the distance between the user and the sensor is less than a predetermined threshold, the keypad is illuminated in anticipation of the user providing keypad input to the electronic device. The sensor can be an infrared, an ultrasonic or a capacitive sensor. Alternately, the sensor can indicate contact between the user and the sensor, wherein the contact does not provide keypad input to the electronic device, for example, when the user touches but does not push a key of the keypad.

The present invention relates to the field of electronic devices in general, and more particularly, to electronic devices and methods responsive to user proximity.
Many electronic devices, such as radiotelephones, include controls which may be used to operate the electronic devices. For example, a radiotelephone may include a keypad used to input information into the radiotelephone such as telephone numbers to be dialed.
Electronic devices may be used over a wide range of operating conditions. For example, radiotelephones may be used in conditions where the ambient lighting is dim. The radiotelephone may, therefore, have the capability to back-light the keypad to assist the user in seeing the keys more clearly in low-light conditions. More specifically, the back-light may illuminate the keys when the user pushes a button or otherwise invokes an operation of the radiotelephone.
Unfortunately, if the ambient light level is too low for the user to see the controls of the electronic device the user may push an incorrect control, thereby causing the electronic device to carry out an unintended operation or provide erroneous input. Once the controls of the electronic device are illuminated, the user may see the error and wish to correct it. The user may, for example, correct the error by deleting the erroneous input and providing the correct input. In view of the above, there is a need for improved interfaces of electronic devices and methods thereof.
In view of the above, it is an object of the present invention to allow improved electronic devices and related methods.
It is another object of the present invention to allow improved interfaces to electronic devices and related methods.
It is another object of the present invention to allow reduction in power consumption of electronic devices and related methods.
These and other objects of the present invention are provided methods and apparatus that illuminate keys of a keypad of an electronic device, such as a radiotelephone, when the proximity of a user to a sensor of the electronic device is less than a predetermined threshold. In particular, a processor of the electronic device controls operations of the electronic device. A keypad includes a plurality of keys, wherein the keypad provides keypad input to the electronic device when at least one of the plurality of keys is pushed. A sensor indicates the proximity of the user to the sensor, whereupon the processor determines the proximity of user to the sensor. When the processor determines that the proximity of the user to the sensor is less than the predetermined threshold, a light illuminates the plurality of keys, thereby improving the visibility of the keys. The sensor can be an infrared or capacitive sensor.
Accordingly, the keys of the electronic device can be illuminated without providing keypad input to the electronic device. For example, when a user""s finger is within a predetermined threshold distance, the keys of the keypad are illuminated in anticipation of the user wanting to use the keypad. The present invention, therefore, may avoid the need to push a key to illuminate the keys of the keypad, thereby allowing an improved interface to the electronic device for the user. Furthermore, the present invention may provide a reduction in power consumption by avoiding unneeded input simply to illuminate the keys so that the user can provide the intended input.
In a further aspect of the present invention, the light illuminates the keys when the processor determines that a user is in contact with at least one of the keys, wherein the contact between the user and at least one of the keys does not provide keypad input to the electronic device. For example, the light can illuminate the keys of the keypad when the user touches, but does not push, one key.
The sensor may include contacts on the keys and a comparator, electrically connected to the contacts, wherein the comparator provides a voltage level in response to contact with the user. The contacts can be made of a conductive material on the keys such as gold, silver, or copper.
In particular, the contacts can include first and second contacts on keys. The first and second contacts are electrically connected to each other in response to contact between the user and one of the keys. For example, the first and second contacts can be on the faces of the keys so that when the user touches a keyface, the first contact is electrically connected to the second contact which causes a detector to signal the processor that the user is touching a key.
In another aspect of the present invention, the light illuminates the keys when the processor determines that the user is in contact with at least two of the keys, wherein the contact between the user and the two keys does not provide keypad input to the electronic device. For example, the light can illuminate the keys of the keypad when the user touches, but does not push, two of the keys.
In a further aspect of the present invention, the keys of the keypad can be in one of two states: depressed and non-depressed. For example, when a key is pressed the key is in the depressed state and when the key is not pressed, such as when the radiotelephone is not being used, the key is in the non-depressed state. According to the present invention, input can be provided to the radiotelephone when a key is in the depressed or the non-depressed state. For example, input can be provided to the radiotelephone when the user depresses a key or when the sensor detects proximity of the user. As a result, the present invention may allow, for example, increased input with fewer keys or allow the number of keys in the keypad to be reduced.
Detected contact by a user can also be used to initiate operations of the electronic device. For example, a radiotelephone that operates according to the present invention can detect contact between the sensor and the user""s face when the user places the radiotelephone near his or her ear. Accordingly, the contact may be used to answer the call rather than by pushing a button or opening a cover of the radiotelephone.

Electronic devices including keypads that illuminate in response to proximity of a user and methods of operating such electronic devices


A device for decomposing images into at least three levels by wavelet transform comprises a first unit executing a first level of decomposition and a second unit executing the higher levels of decomposition by performing a sequence of processing tasks. The tasks are ordered in time by using a sequence of rows, a routing unit serving to configure the second unit when the level of decomposition associated with the processing task currently being executed changes relative to the level of decomposition associated with the processing task executed previously. The processing tasks are ordered so that any given row is associated with only one level of decomposition.

By using the wavelet representation of a signal it is possible not only to decompose the signal into different frequency bands, as is done by Fourier analysis, but also to obtain different representations of the signal at different scales. The extension of this decomposition to two-dimensional (2D) signals also provides information on the orientation of the irregularities present in the image.
The wavelet transform has qualities which are useful for signal and image processing, because it enables a temporal, frequency and multiscale representation of a signal to be obtained. This method of analysis is a logical development of Fourier transform analysis, the dimensional analysis associated with this wavelet transform enabling the signal to be studied at different scales.
By contrast with the analysis of a continuous signal, the mother wavelet translation and expansion parameters vary in a discrete manner for the analysis of a discrete signal. The progressive increase of the expansion factor is obtained by applying the wavelet filtering operation recursively to the same discrete signal.
By way of illustration, a one-dimensional (1D) signal is decomposed by the following procedure: the original signal is decomposed into a detail signal Wd1 amplifying the high-frequency components of the signal and into an approximation signal Wa1 which provides a smoothed view of the original signal. The latter is, in turn, decomposed into a detail signal Wd2 and an approximation signal Wa2. This procedure is then repeated until the desired number of levels of decomposition have been obtained. A series of detail signals, Wd1, . . . , Wdn is obtained, together with a signal Wan, all of which enable the input signal to be analyzed on different scales.
By using orthogonal decomposition filters it is possible to reconstruct the information and suppress the redundancy present in the approximation and detail bands. It is therefore possible to apply an operation of subsampling by a factor two to the output of each filter, thereby providing a concise representation of the information, the number of samples between the input and the output of the transform being conserved.
2D decomposition of a signal is carried out by successive decomposition along the horizontal axis and then along the vertical axis. Three detail subimages LH, HL and HH are obtained, together with an approximation subimage. The signal HH, corresponding to the result of two successive high-pass filters, is commonly called the diagonal signal. Similarly, the signals LH and HL can be related to vertical and horizontal signals respectively. The approximation signal is decomposed again to obtain a multiscale decomposition. The resulting coefficients are interlaced in terms of both orientation and scale.
FIG. 1a shows an interlaced representation of the decomposition of an image. FIG. 1b shows a non-interlaced representation of the decomposition.
2D architectures of the DWT type (an acronym for the English expression "Discrete Wavelet Transform") may be classified according to two different methods. The first method is called "row-column" and the second method is called "row by row".
FIG. 2 shows the row-column decomposition method. The operation is divided into two 1D transforms, of which one, 200, is horizontal and the other, 201, is vertical. The horizontal transform operation 200 is applied initially to an input image 204. The transformed coefficients are placed in a short-term memory 202 with a size of N×M, corresponding to the size of the initial image. The vertical transform operation 201 is then applied in a second step, to provide a final image 205. This structure has the advantage of being easy to implement, since the two transforms 200, 201 are totally independent. A major drawback of this method is the large amount of memory required for this type of implementation. This memory, exclusively reserved for the transform operation, has a size of N×M and must be located close to the processing units to avoid costly reading and writing of the coefficients. This memory significantly increases the total surface area of the component executing the coding. Consequently, this type of structure is little used in practice.
FIG. 3 is a schematic illustration of the nature of a row-by-row transform. This type of transform can reduce the intermediate memory cost. This is because, in this type of implementation, a row memory 302 is used, with a size of L×M, where L is the size of the filter used. This memory replaces the image memory, and allows the short-term storage of the coefficients produced by the horizontal transform unit 300. By way of example, L=3 for the CDF 5/3 wavelet.
The vertical transform operation 301 is then launched as soon as the number of rows in memory is sufficient to apply the vertical filter. With this type of implementation, it is possible to change from an image memory with a size of N×M to a row memory with a size of L×M. For the 9/7 transform, five rows of coefficients must be stored. Only four rows of coefficients are required in some architectures. An inherent drawback of the use of this method is that finer control is required, both in reading to and writing from the buffer memory 302, and in the launching of the vertical transform 301.
FIG. 4 shows an example of an architecture that requires no intermediate memory for storing the wavelet coefficients between the vertical and horizontal passes.
An architecture for reducing the memory requirements was proposed in the paper by Peng Cao, ChaoWang, Jun Yang and Longxing Shi entitled Area-efficient line-based two dimensional discrete wavelet transform architecture without data buffer, ICME 2009, IEEE International Conference on Multimedia and Expo, pages 1094-1097, 28, 3 Jul. 2009. This architecture does not require an intermediate memory, known as a transposition memory, for storing the wavelet coefficients between the vertical and horizontal passes. It also allows the execution of a 5/3 or 9/7 decomposition, direct or inverse according to the configuration. The input pixels 400 are scanned row by row, one pixel being transmitted in each calculation cycle. Two elementary modules 401, 402 are used. A first module 401 performs the vertical transform, using CPE (Column Processing Element) calculation elements 403, 404. A second module 402, receiving the results 407 from the preceding unit 401, performs the horizontal transform, using RPE (Row Processing Element) calculation elements 405, 406. The resulting approximation coefficients are stored 408 in a RAM (Random Access Memory) to enable the next level of decomposition to be executed. Here again, a problem of memory arises. In this example, a quarter of an image has to be stored in the RAM 408.
The paper by H. Liao, M. K. Mandal, and B. F. Cockburn, entitled Efficient architectures for 1-d and 2-d lifting-based wavelet transforms, IEEE Transactions on Signal Processing, 52(5): 1315-1326, 2004, proposes the execution of a multi-level 2D decomposition using a recursive implementation of the DWT transform. The transform module is composed of two 1D transform units, one horizontal and one vertical, separated by a plurality of FIFOs used for storing the coefficients of each level. These FIFOs are used to accumulate a sufficient number of coefficients for the execution of the column by column transform, for each transform level. It was decided that the processing of the first level of decomposition would be carried out in only one out two calculation cycles, so that the higher levels of decomposition could be inserted between the first-level decompositions. Although the architecture ultimately requires only four lines of short-term memory for the execution of the CDF 9/7 transform, a complicated control system is required to manage the various FIFOs as well as the delay registers. This architecture performs the multi-level decomposition of an image by ordering the decomposition tasks related to the different levels on the same row. Since all the levels of decomposition can be processed on the same row, the decomposition unit is used intensively during the processing of these rows, and not at all during the following rows, where there is no need to carry out several levels of decomposition. It is also necessary to reconfigure the processing unit data path at each calculation cycle during the transform rows according to the current level of decomposition. Furthermore, the number of storage registers in the horizontal decomposition units must be increased, and specific addressing must be developed, so as not to overwrite the intermediate coefficients within a row. Thus this choice greatly increases the critical path length, and reduces the overall performance of the transform module. This architecture uses two rows of memory to delay the data produced between the different levels of decomposition and a complex mechanism is used to upload and download the coefficients to and from these memories.
Many on-board applications require the use of wavelet transforms. It is therefore important to find architectures that enable the requisite memory size to be reduced, with the lowest possible difficulty of implementation.
In the rest of the description, the CDF 5/3 and CDF 9/7 filters are used as examples. These are wavelet filters invented by Cohen, Daubechies and Fauveau. Each of these filters has specific properties. The 5/3 filter allows loss-free compression and decompression. The 9/7 filter offers a better compression rate, but introduces losses. The equivalent size of these filters is three coefficients for the 5/3 and five coefficients for the 9/7 filter. Although these two filters are used as examples, the invention can be applied using any type of filter.

Device for image decomposition using a wavelet transform

COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES


To prevent patients from being overexposed or underexposed, it has been attempted to modulate either voltage or current in conventional single energy CT systems. The voltage modulation causes incompatibility in projection data among the views while the current modulation reduces only noise. To solve these and other problems, dual energy CT is combined with voltage modulation techniques to improve the dosage efficiency. Furthermore, dual energy CT has been combined with both voltage modulation and current modulation to optimize the dosage efficiency in order to minimize radiation to a patient without sacrificing the reconstructed image quality.

Conventional computed tomography (CT) systems with an X-ray tube operating at a constant voltage and a constant current face image-quality problems in scanning various parts of a patient in one acquisition or scanning one part where the attenuation strongly depends on a view angle. Since the physical dimensions of certain body parts significantly vary with respect to views, the transmitted X-ray attenuates at a different level. In other words, since a prior art X-ray energy source provides the same spectrum and flux of the X-ray beams to acquire projection data sets regardless of the physical dimensions of a scanned part, an image quality varies depending upon the physical dimension and other variables such as a material distribution. To improve image quality, as the voltage and current are fixedly increased with respect to large dimensional views, a patient is exposed to an unnecessary amount of high radiation while projection data are acquired from small dimensional views. On the other hand, as the voltage and current are fixedly decreased with respect to small dimensional views, image quality suffers from artifacts due to the poor quality of data from large dimensional views. The constant exposure level prevents the optimal data acquisition. Consequently, the patient may be either overexposed or underexposed during the data acquisition.
With respect to the above issue, prior art techniques modulated either a tube voltage or a tube current of a single energy X-ray source. For example, Japanese Patent Publication 53-110495 discloses that an amount of X ray at a detector is kept constant across various parts of the scanned body by modulating the tube voltage based upon a feedback signal from the X-ray detector. In other words, assuming the same X-ray attenuation coefficient through various parts of a different thickness, a large amount of high-energy X ray is projected into a thicker portion while a small amount of low-energy X ray is projected into a thinner portion so that the attenuated x-radiation is constant at the detector across the various portions via a feedback control.
The above prior art technique assumes the constant attenuation coefficient across various parts of the patient body. In contrast to the assumption, various body parts have a different attenuation profile. Furthermore, the voltage is modulated while the scanning process is taking place. In other words, since the voltage is being modulated at various angles about the scanning axis and also at various positions along the same scanning axis, the acquired projection data are not compatible with each other for the image reconstruction processes. For example, for a given projection, there is only a single set of projection data at a particular voltage level, and this projection data cannot be generally combined with another set of projection data at a different energy level due to the energy-dependent nature of the attenuation coefficient. Consequently, image reconstruction fails to yield a desirably artifact-free image.
In this regard, Japanese Patent 2704084 discloses that an attenuated X-ray level is kept substantially constant at various angles and positions along the scanning direction by modulating a tube current level. In order to accomplish the substantial consistency, an attenuated x-radiation value at the present angle and position is approximated to an average attenuated x-radiation value at the previously detected angle and position based upon current modulation. In other words, the tube voltage is kept constant throughout the scanning process while the tube current alone is modulated to avoid the above described projection data incompatibility.
The current modulation is generally useful in controlling the noise level but not the penetration of x-ray beam that relates to the dose efficiency. Roughly speaking, the higher a tube current level is during the projection data acquisition, the lower a noise level becomes in the acquired projection data sets. More precisely, the noise level, variance of the projection data, is inversely proportional to the current level. On the other hand, the tube current is proportional to the dosage to the patient. In this regard, the current modulation may improve image quality and achieve an optimal dosage level in the case of fixed dose efficiency. However, the optimal dosage level can be further reduced by improving the dose efficiency through adjusting the penetration of X-ray beam.
In order to improve the patient safety, an optimal dose efficiency level must be achieved during the CT scanning procedure. That is, the patient is exposed to a minimally necessary radiation level while the image quality in the reconstructed image is not sacrificed. The dose efficiency is generally defined to be (S/N)2 divided by a dose level, where (S/N) is a signal-to-noise ratio. The dose efficiency depends on x-ray spectrum, detector characteristics and attenuation of the imaged subject. Thus, an optimal dose efficiency level is obtained for a particular material of a certain physical size by controlling the spectrum through the tube voltage modulation.
From the above background information, it appears necessary to modulate the tube voltage level in order to optimize the dose efficiency level since a current modulation alone does not achieve the ultimate goals both in patient safety and image quality. On the other hand, from the prior art attempts, the voltage modulation has an inherent issue of data incompatibility among the projection data if images are reconstructed with a single energy CT reconstructor. In this regard, more recent prior art techniques involve dual energy imaging techniques.
Dual energy imaging in CT has been a promising technique since the first days of CT and was even mentioned in Godfrey Hounsfield's paper (1973) that introduced CT. The basic idea is to acquire two data sets at low and high energy levels and to use the pairs of the data sets to deduce additional information about the patient.
The physical basis of dual energy imaging includes two main mechanisms of the interaction of X rays with matter in the clinically relevant diagnostic energy-range from 30 keV to 140 keV, and the two interactions are photoelectric absorption and Compton scattering, each having its own functional dependence on X-ray energy. Photoelectric absorption is a rapidly decreasing function of energy while Compton scatter is a gentle function of energy. As shown in FIG. 1, the photoelectric interaction is a strong function of the effective atomic number (Z) of the absorbing tissue while scattering is nearly independent of Z. The physics enabled Alvarez and Macovski (1976) to develop a mathematical scheme, called dual-energy decomposition, to use the dual energy information.
In addition to the energy dependence, dual-energy decomposition must take X-ray sources into account. Since commercial clinical CT-scanners generally use polychromatic sources, the mathematics of dual energy imaging is not trivial. In this regard, single-energy imaging with a polychromatic source does not have an exact and analytic solution. One mathematical approach in dual-energy decomposition using a polychromatic source has been described in a related U.S. application Ser. No. 12/361,280 filed on Jan. 28, 2009 and Ser. No 12/106,907 filed on Apr. 21, 2008 as well as in a reference entitled as "Analysis of Fast kV-switching in Dual Energy CT using a Pre-reconstruction Decomposition Technique," by Yu Zou and Michael D. Silver (2009). In dual energy computed tomography (CT), fast kV-switching techniques generally alternate voltages between projections (also called views) so that the odd (or even) projections correspond to the low (or high) tube voltage. These references are incorporated into the current application by external reference to supplement the specification. Instead of the polynomial approximation method, in the previously proposed approach combining a linear term with a non-linear beam hardening term, an iterative solution to the dual energy data domain decomposition converges rapidly due to the dominant linear term.
In the past two years, prior art attempts have implemented certain dual energy CT systems. For example, Siemens has installed a number of dual source CT-scanners, which is equipped with two X-ray sources, and each runs at a different energy level for generating the two data sets. Another example is that Philips at their Haifa research facility has developed a sandwich detector where the upper layer records the low energy data and the lower layer records the high energy data. A prototype system is installed at the Hadassah Jerusalem Hospital. In this regard, GE has developed a specialized detector using garnet for capture 2496 total projections per rotation (TPPR) at a high speed. The fast detector has been combined with a fast kV-switching X-ray source to acquire the low and high energy data sets.
TABLE 1 below summarizes advantages and disadvantages of selected ways to acquire dual energy data sets. Fast kV-switching techniques change voltages between projections (also called views) so that the odd and even projections respectively correspond to the low or high tube voltage. Among these prior art approaches, the fast kV-switching appears an attractive technique for dual energy acquisition for a number of reasons. Since the dual source CT-scanners and the sandwich detector CT-scanners respectively require additional costs for the dual X-ray sources and the sandwich detectors, they may not be cost-effective to obtain dual energy data sets. Similarly, although GE's detector for fast kV-switching energy CT is not summarized in TABLE 1, the semi-precious gem detector also incurs additional costs. In addition, both the dual source CT-scanners and the sandwich detector CT-scanners must resolve other technical difficulties that are associated with these systems as listed in the table below. On the other hand, although the slow kV-switching does not require additional parts or equipment, dual energy data sets result in poor temporal registration that is off by at least one rotation period as well as poor spatial registration in particular from helical scans. For these reasons, the prior art technologies remain to find a cost effective system and method to utilized the dual energy data for CT.
TABLE 1OptionsAdvantagesDisadvantagesFastTemporal and spatialLimited energy separationkV-registration very good.unless square-wave waveformswitchingData domain methodsdeveloped.(alternatingpossible leading to betterDifficult to equalize dose/noiseviews)IQ and flexibility.between high/low data sets.Helical acquisition noDevelopment time and cost forproblem.fast, switching HVPS.SlowGood energy separation.Poor temporal registration; offkV-Easy to equalizeby at least one rotation period.switchingdose/noise betweenPoor spatial registration,(alternatinghigh/low data sets.especially if doing helical scansrotations)Little equipmentand thus limited to imagedevelopment necessary.domain methods.Little or no added H/WHelical scans may require lowercosts.pitch and thus more dose.DualGood energy separation.Temporal registration off by ¼sourceEasy to equalizeof the rotation period.dose/noise betweenSpatial registration requireshigh/low data sets.tube alignment.Cost of two imaging chains.Field-of-view for dual energylimited by the smaller of thetwo imaging chains.Cross-scatter contamination.SandwichPerfect temporal andLimited energy separation.detectorspatial registration.Cost and development of theData domaindetector.decomposition methodsvalid.Helical acquisition noproblem.
As already shown in TABLE 1, prior art fast kV-switching techniques without the use of dual sources or special detectors nonetheless have both advantages and disadvantages in acquiring dual energy data sets. The prior art fast kV-switching techniques have very good temporal and spatial registrations between corresponding high and low energy projections, which make data domain methods possible and lead to better IQ and flexibility. In addition, prior art fast kV-switching techniques acquire good dual energy data sets also through helical projections. A disadvantage is the one view misregistration between corresponding high and low energy projections. Another problem is the difficulty of high noise in the low energy data because it may be technically difficult to swing the mA as fast as the kV.
Regardless of the clinical significance, several hurdles remain for successful dual energy imaging. One important image quality issue is related to the different dose and noise levels between the two data sets. Depending on how the dual energy is achieved, the low energy data set could be very noisy compared with the high energy data set because X-ray tubes are less efficient at lower voltages, and the lower energy X rays usually have worse penetration in tissues, which will be a problem for larger patients. The same issue may be also problematic with scanning various parts of the same patients since the physical dimensions of these body parts significantly vary.
With respect to dual energy CT, one algorithm is described to modulate a current level in "Dual energy exposure control (DEEC) for computed tomography: Algorithm and simulation study," Phillip Stenner and Marc Kachelrie, Med. Phys. 35 (11), November 2008. The prior art technique claims that DEEC minimizes the noise in the final monochromatic image while it keeps the dose constant. Alternatively, the prior art technique claims that DEEC minimizes the dose while it keeps the noise constant. In other words, either the dose or the noise is improved by the current modulation in the above DEEC. In this regard, the prior art DEEC still fails to improve the dose efficiency.
Despite the above described prior art techniques, patient safety from X-ray overdose remains to be improved without sacrificing image quality. The advantages of dual energy CT includes some improved image quality and other potentially significant contributions.

Voltage and or current modulation in dual energy computed tomography


A Device and method are provided to split a single chambered IAB device into at least two IAB distinct chambers, that work in conjunction with each other, each being smaller than the single chamber, but the combination of the two chambers may be greater than the single chamber.

1. Field of the Invention
This invention relates generally to cardiopulmonary support equipment, and more particularly, to intra-aortic balloon pumping devices and methods in which a working fluid is used to selectively inflate and deflate two or more intra-aortic balloons.
2. Description of the Related Art
Intra-aortic balloon catheters are used to reduce the burden on a still-beating heart, or to force blood to flow to the arteries, for example, the coronary arteries which are not receiving an adequate blood supply.
Intra-aortic balloon catheters typically consist of an intra-aortic balloon ("IAB"), an extension catheter and a connecting catheter which joins the balloon and the extension catheter. The extension catheter, connecting catheter and balloon are in fluid communication so that forcing gas through the connecting catheter causes the IAB to inflate and removing gas through the connecting catheter caused the IAB to deflate.
IAB catheters can be positioned in a patient's body using minimally-invasive catheterization procedures, rather than surgery. Typically, the furled intra-aortic balloon is inserted through a puncture wound in the groin into the patient's femoral artery and is advanced until it is disposed within the patient's descending aorta. Now the heart can be assisted by inflating and deflating the IAB in counterpulsation to the beating heart.
In designing IABs, a consideration is the benefits of minimizing the size of the wrapped membrane of the balloon which dictates the minimum size of the catheter that has to close off the puncture site in the femoral artery following the wrapped balloon membrane passage. The catheter should also be large enough to allow for the fast passage of gas, heretofore, described. All this usually causes limitation in the design and benefit to the patient.
First of all, certain percentage of LAB patients have atherosclerotic disease in their femoral and iliac arteries. That may lead to partial or near total occlusion of these vessels. That, in turn, may cause difficulties with inserting of an IAB and could provoke limb ischemia due to restricted distal blood flow. Similar complication may occur in smaller patients without this disease. It is estimated that 10-15% of IAB patients suffer from limb ischemia. Some patients are even completely denied the benefits of IAB therapy because of insertion difficulties.
A second problem is the removal of the IAB at the end of the procedure. A typical catheter has an OD of 9 to 10 Fr. After IAB removal, a clinician has to stop arterial bleeding which may not be a simple task. Pressure is usually applied to the groin area of the patient for several hours which is uncomfortable for the patient and present a constant risk of massive bleeding. Reduction of the OD of the inserted device from say 10 Fr or 11.5 Fr in the case of present insertion using a sheath to say 6 or 8 Fr will significantly improve hemostasis as known from PTCA and angiography procedures which use a smaller catheter and have a reduced time to hemostasis after the removal of the catheter.
Still another limitation of IAB therapy is the inability of the patient to move while receiving the IAB therapy. The reason for this is that movement often causes kinking of the IAB catheter which normally does not occur when small catheters, such as those used in PTCA and angiography are used.
Finally, the overall balloon volume of a catheter is limited by only a few standard volumes being presently offered for use.
An object of the present invention is therefore to overcome the various previously stated problems of the prior art by providing:
a. Smaller OD balloons to reduce the size of the insertion puncture; PA1 b. An ability to mix and match different volume size balloons to obtain the exact volume needed without having to stock numerous sizes of balloons to obtain the proper volume, and PA1 c. Reducing the overall OD of the total catheter in order to facilitate the insertion of the catheter into arteries that are restricted in size for one reason or another while allowing for the maximum flow of blood through said arteries when the catheter is in place.

Device and method for an IAB assist with multiple balloons


In a first embodiment, a wind to energy conversion system is constructed out of a number of modular power units (110), each modular power unit (110) comprised of 36 air jet tunnels (106). Each air jet tunnel (106) is constructed using a cantilever array mounted in a cascaded frame (104) with each cantilever (102) attached on one edge to a window edge of the frame (104). The cantilever (102) is constructed of a brass (130) layer sandwiched between two layers, each layer composed of an electrode (126) attached to a Poly Vinylidene Fluoride (PVDF) (128) layer. Each modular power unit (110) is mounted in a case (108), and a set of cases are mounted in a panel (114) attached to a pedestal (116). The cantilever arrays (117) are wired together into electrical regulating circuits that generate power with a high wind to power conversion efficiency. Other embodiments are presented.

Current wind power generators generally employ wind turbines and electric motors to generate electricity. These systems are inefficient and expensive to construct and maintain. They are also noisy, intolerant to damage, and relatively difficult to transport and assemble1,2. They can also impose safety and environmental concerns. Unfortunately, a compact, modular, bladeless wind energy system does not exist although some approaches have been proposed. The potential advantages to its development include reduced noise, size, and cost combined with improved portability, efficiency, and cost-effectiveness.
The most common approaches to the design of a bladeless wind generator are based on electro-kinetic phenomena that involve the interaction between an electrostatic and a charged medium in a liquid phase. Electro-kinetic systems require designs that convert air movement to liquid movement and that separate and collect charge for electrical output. Air-liquid and liquid-solid interfaces have to be included in such system, resulting in very low conversion efficiency and high cost of manufacture. For example, Marks, "Charged aerosol generator with uni-electrode source" U.S. Pat. No. 2,406,396, 19773 proposed a vaneless ion wind generator that produces electrical energy directly by using the wind to pump charged aerosols (water droplets) from one electrode to another, with no moving parts. It is obvious that most of the wind's kinetic energy is lost in order to move the charged aerosol from one electrode to another. Daniel Y Kwok, et al, "Electrokinetic microchannel battery by means of electrokinetic and microfluidic phenomena", Journal of Micromechanics and Microengineering, 13, 964-970, 20034 proposed a microfluidic approach to extract energy from a pressure driven liquid flow in a microchannel.
However, this approach also exhibits low efficiency and high cost because it requires an additional energy-absorbing process to drive the liquid flow in the microchannels where only a weak electric current is induced due to the presence of an electrical double layer in the interface between the liquid and microchannel walls.


High performance proprietary cementitious concretes or mortars developed for use as patch repair materials for corrosion damaged concrete often have high resistivities that inhibit the performance of sacrificial anodes located within the patch repair areas. A method of repair is disclosed which comprises removing the corrosion damaged concrete to form a cavity to receive a concrete repair material and forming within this cavity a smaller distinct cavity for assembling a sacrificial anode assembly and placing within this second cavity a pliable viscous ionically conductive backfill and a sacrificial anode and an activating agent to form a sacrificial anode assembly and connecting the anode to the steel and covering the anode and the backfill in the second cavity with a repair material to restore the profile of the concrete structure. In this arrangement a high resistivity repair material promotes the flow of protection current to steel in adjacent contaminated concrete that is at risk of corrosion.

Steel reinforced concrete structures suffer corrosion induced damage as the result of carbonation or chloride contamination of the concrete. The steel reinforcement corrodes to produce products that occupy a larger volume than the steel from which the products are derived. As a result expansion occurs around reinforcing steel bars. This causes cracking and delamination of the concrete cover to the steel. Repairs involve removing this patch of damaged concrete. It is good practice to remove the concrete (break it out) behind the corroding steel and to remove as much of the contaminated concrete as possible. The concrete profile is then restored with a compatible cementitious repair concrete or mortar. The concrete then consists of the parent concrete (remaining original concrete) and the repair material at the patch. Previous research effort has resulted in the generation of a number of competing high performance proprietary cementitious concretes or mortars for use as concrete repair materials.
The parent concrete adjacent to the repair area is likely to contain some aggressive contaminants as the result of its exposure to the environment that caused the damage at the patch. Sacrificial anode assemblies may be tied to the steel to provide galvanic protection to the steel that is in the adjacent parent concrete prior to covering the steel and restoring the concrete profile with the repair material. One example is shown in Repair Application Procedure number 8 published by the American Concrete Institute (ACI). The anode assembly typically comprises a pre-assembled anode and backfill wherein the backfill contains an activating agent and the assembly forms a rigid assembly that can be tied to the steel exposed in the cavity formed by the removal of the damaged concrete. One problem with this arrangement is that the current delivered to the steel in the adjacent concrete depends on the resistivity of the concrete repair material. Repair materials with a high resistance to the ingress of contaminants also tend to have a high electrical resistivity, but a high electrical resisitivity of the repair material reduces the current output of the anode and therefore the protection current delivered to the steel in the parent concrete adjacent to the repair. A proposed solution to this problem is to use a low resistivity bridging mortar to connect the preformed anode assembly tied to the steel to the original (parent) concrete prior to installing the concrete repair material. However this compromises the quality of the repair material and increases the number of interfaces between the sacrificial anode and the parent concrete where further problems may occur.

Sacrificial anodes in concrete patch repair


A process for reducing sulfur compounds in naphtha to produce gasoline of ultra-low sulfur content, i.e., 10–30 ppm of sulfur, from a fluidized catalytic cracking reactor effluent stream, withdraws a high sulfur content sidestream of catalytically produced medium and heavy cat naphtha with an endpoint of +430° F. that is fed to a side column where any thiophenic and benzothophenic compounds are catalytically reacted with hydrogen to convert them to hydrogen sulfide. The desulfurized light and mid-cut naphtha is returned to the main fractionation unit and the heavy catalytic naphtha is withdrawn as a product stream from the bottom of the side column.

International environmental conventions and trade agreements include provisions requiring national and regional legislation for the establishment of more stringent specifications on motor vehicle fuels to meet stricter air pollution emission standards from automobiles and other motor vehicles. Reduction in sulfur compounds is included in the new fuel specifications.
Engine manufactures are also establishing stricter fuel specifications for their new engines to meet these emission standards. Sulfur in gasoline reduces the effectiveness of catalytic converters and on-board diagnostic equipment in vehicles, thus increasing tailpipe emissions. The reduction of sulfur content in gasoline for internal combustion engines is included as one of the requirements in these more stringent specifications.
The sulfur containing compounds typically found in refinery feedstocks, and which be removed in order to meet impending regulatic thiophene, methylthiophene, tetrahydrothiophene (THT) C2-thiophenes, C4-thiophenes, thiophenol, methylthiophenol, benzothiophene, methylbenzothiophenes and alkylbenzothiophenes. Meeting the 30 ppm specification, which is anticipated for 2005, is projected to cost from 2–5 cents per gallon and will require very substantial capital investments by refiners.
As used herein ultra-low sulfur gasoline means naphtha gasoline products containing no more than 10–30 ppm of sulfur.
As used herein thiophenes and thiophenic compounds refer to all thiophene and alkylthiophenes and alkylthiophenic compounds; and benzothiophenes and benzothiophenic compounds refer to all benzothiophene, alkylbenzothiophenes and alkylbenzothiophenic compounds.
A used herein, the term distillation column reactor means the concurrent reaction and fractionation of a process stream in a column. For the purposes of the present invention, the term catalytic distillation includes reactive distillation and any other process of concurrent reaction and fractional distillation in a column.
The gasoline produced from the effluent of fluid catalytic cracking (FCC) units contributes more that 90% by weight of the sulfur in the gasoline pool. The major portion of the sulfur content in the naphtha stream is attributed to thiophene, thiophenic compounds, benzothiophene, benzothiophenic compounds and other high boiling range +430° F. compounds (alkylbenzothiophenes, benzothiophenes, for example). Unless removed, these heavier compounds can be entrained in the finished gasoline product. A reduction in FCC naphtha sulfur would be a significant step in meeting the current and future specifications for a cleaner burning and more efficient fuel.
Methods for the desulfurization of FCC naphtha are well known in industry. The following four prior art refinery processing options for reducing sulfur content in FCC naphtha are available:
1. Pretreatment of FCC feed—                Pretreatment of the FCC feed, i.e., hydrotreating the feed, can reduce the sulfur in all products produced from the FCC, including the naphtha. However, to reach the low sulfur levels required for the foreseeable "ultra-low sulfur" specifications, post-treatment is still required.
2. Reducing the naphtha distillation endpoint—                Reducing the naphtha endpoint by undercutting the naphtha product can drop the thiophenic and benzothiophenic compounds from the naphtha into the light cycle oil ("LCO"), thereby reducing the sulfur content of the naphtha. This process reduces the volume of desired gasoline produced and does not reduce sulfur in the light fractions.
3. Increase sulfur conversion in the FCC reactor—                Increasing sulfur conversion by the use of catalytic changes, by catalyst, reactor additives or by operating changes can only achieve a modest reduction in the sulfur content of the end products. In the finished FCC gasoline, this so-called "trimming" still requires further post-treatment to significantly reduce the sulfur content.
4. Post-treatment of the FCC naphtha—                Post-treatment of the FCC naphtha utilizing a traditional hydrotreating process is currently the most widely-used method of reducing sulfur to the desired low levels. There are currently numerous commercial and proprietary processes for post-treatment hydrotreating of FCC gasoline. The principal drawback to the use of this process is that post-hydrotreating reduces both the octane and volume of gasoline produced.
As used herein, the term "full-range naphtha" means the petroleum fraction from C5+ to 430° F. final boiling point. As used herein "gasoline" or "FCC gasoline" refers to naphtha that is to be blended with other components to produce a finished gasoline for use as an automotive fuel.
One post-treatment process utilizes prior art catalytic distillation that is a "non-traditional" hydrotreating process. This prior art catalytic distillation process transfers stabilized full range naphtha from the FCC unit to a naphtha splitter and splits the naphtha by distillation into three cuts, i.e., light cat naphtha (LCN), medium cat naphtha (MCN) and heavy cat naphtha (HCN). The LCN is further processed in a hydrotreating unit. The MCN and HCN are subjected to a hydrodesulfurization process. This process utilizes an outside distillation column that splits the naphtha first and then desulfurizes the naphtha.
The processes known to, and disclosed in the prior art for use in reducing sulfur in gasoline require major capital investments. Accordingly, further substantial capital investments will be required if these prior art processes are utilized to produce gasoline that meets the stricter ultra-low sulfur specifications of governmental environmental regulations and of the engine manufacturers.
It is therefore an object of the present invention to provide an improved process for desulfurizing naphtha/gasoline fractions that retains the high octane naphtha components and does not reduce the volume of naphtha fractions recovered from the FCC unit.
It is a further object of the invention to provide a process that minimizes the capital expenditures required to meet governmental regulations and allow refinery-produced finished gasolines having ultra-low sulfur content to be sold for use in the world markets that have established requirements for this type of fuel.
Yet another object of the invention is to provide an improved desulfurization process that is easy to control and that maximizes the end-product gasoline.

Desulfurization of a naphtha gasoline stream derived from a fluid catalytic cracking unit


An electrical connector (100) comprises a first connector (1) and a second connector (2) electrically connected together by a printed circuit board assembly (3); a tubular shaped first shielding member (4) enclosing the printed circuit board assembly (3), partial of the first and second connector; a second shielding member (5) assembled to first shielding member and retaining the first connector and the second connector.

1. Field of the Invention
The present invention generally relates to electrical connector, and more particularly to a shielded electrical connector for high-speed transmission.
2. Description of Related Art
TW patent No. 239609 issued to Huang on Jan. 21, 1995 discloses an electrical connector. The electrical connector includes a first connector and a second connector interconnected each other via plurality of wires. The wires with opposite ends thereof are soldered to corresponding contacts of the first connector and the second connector, respectively. The electrical connector may result in lower productive efficiency and higher productive cost. With development of an electronic development, the aforementioned electrical connector is unable to meet complex and powerful function requirement. So an improved electrical connector (adaptor) is emerged in the market. The adaptor includes a first connector and a second connector connected together via a printed circuit board, and some other electronic elements, IC chip, resistor, capacitor etc. are also mounted to the printed circuit board. However ever, those electronic elements are delicate and unable to bear high thermal environment and easily to be damaged.
Hence, an improved electrical connector is highly desired to overcome the disadvantages of the related art.


A computer-implemented method for determining the healthiness of nodes within computer clusters may include (1) identifying a computer cluster that includes a plurality of nodes configured to provide substantially continuous availability of at least one application, (2) identifying at least one operating system kernel installed on at least one of the nodes, (3) configuring the operating system kernel to (a) asynchronously monitor performance of the node and (b) determine, based at least in part on the node's performance, whether the node is sufficiently healthy to execute the application, (4) receiving a notification from the operating system kernel that indicates that the node is not sufficiently healthy to execute the application, and then (5) performing at least one action configured to enable the computer cluster to provide substantially continuous availability of the application despite the unhealthy node. Various other systems, methods, and computer-readable media are also disclosed.

In a high-availability configuration, a computer cluster may include multiple nodes configured to provide high availability of at least one application. Such a configuration may be implemented in an effort to ensure that at least one node within the computer cluster is capable of executing the application at any given time. For example, a cluster engine may select a particular node within the computer cluster to execute the application but later determine (whether accurately or in error) that the node is not healthy enough to continue executing the application. In this example, upon determining that the node is not healthy enough to continue executing the application, the cluster engine may direct the application to fail over from the apparently unhealthy node to another node within the computer cluster in an attempt to reduce application downtime.
Unfortunately, while existing cluster technologies may facilitate application failover from one node to another node, such cluster technologies may also suffer from one or more shortcomings and/or inefficiencies that potentially lead to application downtime. For example, existing cluster technologies may implement a heartbeat mechanism in which the nodes within the computer cluster send periodic heartbeats (via a high-availability agent) to the cluster engine to indicate that such nodes are healthy. In this example, if the node executing the application experiences a system failure shortly after sending a heartbeat, the cluster engine may remain unaware of the node's system failure until the next time that the cluster engine is expecting a heartbeat from the node. As a result, the cluster engine may be unable to direct the application to fail over to another node within the computer cluster (potentially leading to application downtime) until the cluster engine determines that the node executing the application failed to send a timely heartbeat.
In some examples, existing cluster technologies may also determine in error that the node executing the application is unhealthy. For example, even though the node executing the application is completely healthy, the node's CPU may become so overloaded that the node is unable to send a timely heartbeat to the cluster engine. In this example, as a result of the node's inability to send a timely heartbeat, the cluster engine may determine in error that the node is not healthy enough to continue executing the application. Upon determining in error that the node is not healthy enough to continue executing the application, the cluster engine may direct the application to fail over from the apparently unhealthy node to another node in an unnecessary attempt to reduce application downtime.
In another example, the cluster engine may queue a heartbeat received from the node executing the application. However, in this example, the cluster engine may become so overloaded that the cluster engine is unable to process the heartbeat received from the node within a predetermined time interval. As a result of the cluster engine's inability to process the heartbeat received from the node within the predetermined time interval, the cluster engine may determine in error that the node is not healthy enough to continue executing the application. Upon determining in error that the node is not healthy enough to continue executing the application, the cluster engine may direct the application to fail over from the apparently unhealthy node to another node in an unnecessary attempt to reduce application downtime.
As such, the instant disclosure identifies a need for systems and methods for efficiently and accurately determining the healthiness of nodes within computer clusters to avoid (or at least further reduce) application downtime.

Systems and methods for efficiently determining the health of nodes within computer clusters


The invention comprises a process for obtaining a gas from a fluid fuel and an oxidising fluid, said process comprising steps in which the incoming fluid is subjected to temperature, photocatalytic action and reaction with catalysts, all this within a device with a tubular structure which the incoming fluid circulates through in a spiral manner, between a fixed bed attached to the walls of the duct and a circulating bed with an ionised gas stream that occupies a central position of the duct, producing a gas obtained.

Conventional systems of partial oxidation by ionised gas streams, known as thermal plasma torches, use a reactor with at least one plasma torch inside, in order to generate intense heat through which passes at least one reagent that provides oxygen and at least one fuel in gas, liquid or solid form, such as hydrocarbons, biomass, solid organic waste and pyrolysis gas, to produce carbon monoxide and hydrogen when the objective is to generate synthesis gas, or carbon dioxide and hydrogen when the objective is to generate hydrogen.
Said conventional systems for partial oxidation with plasma torches to generate heat generally comprise at least one reactor, a thermal plasma torch within the reactor and a way to feed in the reagents. These reactors usually comprise a metal or ceramic container through which the ionised gas of the plasma torch and the incoming fluid usually circulate.
In these conventional systems, not all the molecules of the fuel and oxidising agents come in contact with the plasma torch and not all the holding times are the same for all molecules, since a currents are formed inside the reactor with different speeds and distances with respect to the plasma torch, giving rise to a certain amount of unreacted fuel (URF) which shall hereinafter be referred to by its acronym.
In order to prevent the aforementioned problems, we have tried to place the wall of the reactors close to the plasma torch so that when the incoming fluid circulates around the ionised gas of said torch there is a propagation of free radicals causing the partial oxidation of the incoming fluid; however, the walls of the reactor suffer accelerated deterioration due to the high temperature at which the plasma torch operates, which is why the walls of the reactors are sometimes cooled, which reduces the efficiency thereof. On the other hand, if in this system we make the incoming fluid circulate at a greater speed in order to cool down the walls and thus prevent them from damage, then the portion of URF increases the efficiency of the process also decreases.
In the current state of the art there are patents where the fuel and the oxidising agents are introduced around the plasma torch in order to achieve greater efficiency, reducing the percentage of URF and also keeping the walls of the reactor at a temperature much lower than that of the plasma torch. Some of these use the term steam reforming instead of partial oxidation, and they use the term synthesis gas for the partially oxidised gas containing mostly hydrogen with carbon monoxide or with carbon dioxide.
The company Foret Plasma Labs LLC has carried out efforts in this direction through U.S. Pat. No. 9,163,584 of 20 Oct. 2015, which discloses a cylindrical reactor of ceramic material with a plasma torch connected to a turbine that reforms fuel in a compressed air burner, flowing as a vortex. Foret Plasma Labs LLC, by means of patent U.S. Pat. No. 7,622,693 of 24 Nov. 2009, also discloses a vertical truncated cone reactor with an induction plasma torch, where the raw material enters as a vortex from the top, which has the greatest diameter, towards the bottom, which has the smallest diameter. The same company, in patent US 2014/0209573 of 31 Jul. 2014, discloses the same as the previous one, only that it is aimed at producing synthesis gas for supplying power plants using a combination of induction plasma applied from outside the reactor and electrical arc plasma with the electrode inserted in the central part, within the cylindrical or truncated cone reactor, so that the incoming gas rotates as a vortex around the latter.
Igor Matveev was granted U.S. Pat. No. 7,973,262 B2 in July 2011 regarding steam reforming by plasma torch, using a device that comprised a triple vortex, with the reagents (fuel and oxidising agent) circulating in an opposite direction to that of the ionised gas of the plasma torch.
The company Hynergreen Technologies S.A., in patent PCT/2007/141350 filed in December 2007, discloses the process under which fuel can be reformed with steam at low temperature and at atmospheric pressure, via induction plasma with dielectric-barrier discharge, wherein the cathode is a steel cylinder with barely perceptible roughness, achieving a conversion of approximately 0.006 m3/hour applying a power of 15 to 30 kWh with a frequency from 3 to 15 kHz at temperatures below 500° C. and at atmospheric pressure, achieving approximately 0.0002 m3/kWh consumed by the plasma, with 15.7 minutes of holding time.
The company Alter NRG Corp. was granted U.S. Pat. No. 9,005,320 in August 2015, which discloses a vertical cylindrical device with the inlet for the plasma torch at mid-height. The company Platinum, in U.S. Pat. No. 6,680,137, discloses a reactor similar to that of Alter NRG, incorporating heat recovery, declaring as its achievement the conversion of approximately 4.54 kg of methane per square metre of internal surface of the reactor.
The company Plasco in patent CA 2424805 discloses a two-step photo-reactor for fuel reforming with steam or oxygen, wherein in the first step ash or coal is extracted in order to apply in the second step a plasma torch such as to produce with an oxidising agent a partial oxidation and thus obtain more synthesis gas in the system.
Siemens, in patent US 20150252274, discloses a plasma reactor wherein it uses low temperature steam to cool the walls of the photo-reactor and thus bring the fuel gas closer to the plasma torch. Drexel University, in U.S. Pat. No. 7,867,457 of 2011, highlighted as a novelty the different forms of turbulence that may be caused in cylindrical reactors with plasma torches in order to accelerate the partial oxidation process of the fuel gas.
It would be ideal that, at a pressure close to the atmospheric pressure, at temperatures of less than 750° C., with a holding time of less than 10 seconds and consuming less than 1 kWh per kg of carbon contained in the fluid fuel, the incoming fluid achieved, in a single pass, a partial oxidation of the fluid fuel, with a conversion to gas obtained of more than 80%.
The current state of the art has not found an economical and practical solution to achieve these conditions in fuel reforming, and this is precisely what was achieved with this invention.

Process for the partial oxidation of fuels and the device for applying said process


An optical time multiplexer for generating an N Gbits/s output signal (36) from n data modulated input pulse streams (21, 22) with a pulse frequency of N/n GHz, where nεIN and n≧2, with a combiner device for passively interleaving the n input pulse streams (21, 22) is characterized by at least n−1 first phase shifting elements (25) tuning the optical phases of at least n−1 input pulse streams (22) and being connected to a controller device (32), which derives at least n−1 control signals from a comparison of the optical phases of the n input pulse streams (21, 22) and controls the at least n−1 first phase shifting elements (25) such that the optical phases of all n input pulse streams (21, 22) are locked with respect to each other. This optical time multuplexer reduces the drifting penalty of ODTM signals due to multiplexer instability, it prohibits the broadening of RZ pulses, and it grants the possibility to easily generate carrier-suppressed RZ signals or similar modulation formats.

The invention is based on a priority application EP 02 360 159.4 which is hereby incorporated by reference.
The invention relates to an optical time multiplexer for generating an N Gbit/s output signal from n data modulated input pulse streams with a pulse frequency of N/n GHz, where nεIN (IN=natural series) and n≧2, with a combiner device for passively interleaving the n input pulse streams.
An optical time multiplexer of that type and the related method of signal transmission was described by M. Nakazawa, T. Yamamoto and K. R. Tamura in ECOC 2000, presentation 2.6; see also Electron. Lett. 36, p. 2027–2028 (2000).
The optical time multiplex technique is a method for transmitting a plurality of channels as a single optical signal. For coding, the signals of the channels are interleaved into the single optical signal. The optical demultiplexing by gating of the single optical signal according to a fixed time schedule allows the recovery of the original channel information.
In order to generate e.g. a 160 Gbit/s RZ (return to zero) signal out from four 40 GHz pulse streams, the four 40 Gbit/s RZ pulse streams are passively interleaved in a combiner (coupler) device after introducing proper mutual delay times of 0, ¼, ½ and ¾ bit periods (one bit period=25 ps) to the four signals.
Production tolerances of the equipment and temperature drift usually leads to non-constant optical phases between the four signals which leads to non-constant interference between different bits and thus to drifting and worst-case signal distortion. This must be taken into account by using very short pulses with a 30 dB extinction at the position of an adjacent bit, so the interference can be neglected. However, such short pulses are highly susceptible to dispersion,. Moreover, the non-constant optical phases between the four signals lead to a strong penalty at the receiver after pulse broadening due to dispersion.
Nakazawa et al. used very short pulse widths on the order of 200 fs and a complex pre-chirping technique applying a grating pair, a spatial light modulator and a reverse dispersion fiber to compensate for dispersion during multiplexing.
I. Moita and N. Edagawa, OFC 2002, Presentation TuA4, p. 5–6, showed that good long distance transmission (2000 km) properties of optical time division multiplex (OTDM) signals can be achieved with carrier suppressed RZ signals having a phase shift of 180° between two interleaved channels. However, the generation of carrier suppressed RZ signals suffers from the same difficulties as the generation of time multiplexed signals in general.
It is the object of the invention to present an optical time multiplexer which reduces the drifting penalty of ODTM signals due to multiplexer instability, and which avoids worst-case distortions which are likely in the case of broad RZ pulses with non-constant mutual phase differences, and which grants the possibility to easily generate carrier-suppressed RZ signals or similar modulation formats.


A military vehicle configured for transport by cargo aircraft. The vehicle has a cab portion that can be reduced in height by removing and/or collapsing and/or telescoping various components of the cab, such as the doors, roof, roll bar, windshield, and/or steering column.

Tactical wheeled vehicles for military operations are often transported into an operational theater on transport aircraft. The tactical vehicles must be able to fit into the relatively confined space of the cargo holds of these aircraft.
Although some wheeled vehicles are relatively compact and are able to fit into the cargo holds of many different transport aircraft relatively easily, other vehicles (e.g., military ambulances and command/control shelters) are comparably larger due to the functions which these other vehicles serve. The larger sizes of these other vehicles has heretofore dictated that larger transport aircraft be used to transport them into the operational theater. Larger transport aircraft, however, are more expensive to operate and/or may be more limited in terms of where they can land. Therefore, there is a need to be able transport larger tactical vehicles using smaller transport aircraft to do so.
While there are a number of example of trailers or other shelter parts of vehicles which can be reduced in size for transport, such as is used in the recreational vehicle art, such methods and structures can not be easily used for the cab portion of a vehicle whether the cab is separate or an integral part of the vehicle.
U.S. Pat. No. 5,282,661 for a collapsible driver's cab for a truck discloses a vehicle in which the upper parts of the wall panels are connected to the lower parts by hinges and the roof is removable.

Height reduction for tactical truck system


The present invention relates to a hard X-ray photoelectron spectroscopy (HAXPES) system comprising an X-ray tube, an X-ray monochromator, and a sample. The X-ray tube provides a beam of photons, which via the X-ray monochromator is directed through the system so as to excite electrons from the illuminated sample. The X-ray tube is connected to a monochromator vacuum chamber in which the X-ray monochromator is configured to monochromatize and focus the beam onto the sample. The monochromator vacuum chamber is connected to an analysis vacuum chamber, the illuminated sample being mounted inside the analysis vacuum chamber and the analysis vacuum chamber being connected to an electron energy analyser. The electron energy analyser is mounted onto the analysis vacuum chamber. Further, the beam of photons provided from the X-ray tube is divergent and has an energy above 6 keV. The X-ray monochromator also comprises a curved optical element arranged to both monochromatize and focus the diverging beam of photons.

To date, the majority of HAXPES experiments for different scientific and industrial purposes have been conducted on the approximately only 20 existing beamlines situated at synchrotrons worldwide. These few synchrotrons around the world are very large-scale facilities and belong to national laboratories. The small number of available beamlines and related instrumentation, the significant costs for operating them and associated access limitations, have restricted the amount of output and development efforts of the HAXPES technique. The main reason for HAXPES being confined to synchrotrons is the dramatic decrease in photo-ionisation cross sections with an increase in X-ray energy. In order to counteract said decrease in photo-ionisation, highest possible X-ray intensities combined with highly efficient photoelectron analysers with, in relative terms, very large acceptance angles are necessary.
Even though HAXPES is also afflicted with certain limitations, just as all other experimental techniques, there is a strong motivation to pursue this technique, including the ability to study bulk materials, buried layers and interfaces, and samples without any need of surface preparation. These measurements are enabled by the increase in information-depth with increasing photon energy.
The previously mentioned lack of wide ranging access to HAXPES facilities combined with a large number of potential applications is a strong motivation to develop the laboratory-based HAXPES system here described. Up to now, the development of laboratory systems has been impeded particularly by the limited availability of high intensity, monochromated X-ray sources and large angle, high-energy analysers. Therefore, only a very small number of systems have been developed so far, and then with a significantly lower maximum photon energy of 5.4 keV (Cr Kα).
In addition to the much higher photon energy, the laboratory-based HAXPES system according to the present invention comprises three separate vacuum chambers: 1) a monochromator chamber housing a monochromating optical element, 2) an X-ray tube housing an electron gun and a jet of liquid Gallium, and 3) an analysis chamber housing the photo-electron energy analyser and a fast-entry load lock in which the sample to be analysed is introduced into the vacuum system.
As mentioned initially, prior to the laboratory-based HAXPES system here described, synchrotron light sources have been in use to create X-rays for photo-electron spectroscopy experiments at the same high excitation energies. Such experiments are normally placed in a separate room, not accessible during experiments due to the harmful radiation levels. Experiment control is therefore normally made remotely. Other types of equipment in which these high excitation energies typically are used are in X-ray diffractometers. These types of experiments are normally enclosed in a cabinet, housing all instrumentation and by its size and thickness forming radiation protection.
Due to the demands on the setup, especially relating to operation and safety, the complexity on the construction of a HAXPES system increase with an increased size and maximum photon energy.
Thus, there is a need to address the difficulties in HAXPES system design associated with increased maximum photon energy in a compact embodiment.

Hard X-ray photoelectron spectroscopy system


A key blank or key has a rectangular parallel metal shaped blade which has side edges formed with grooves for cooperating with a complementary shaped keyway; the sides of the blank having a portion grooved for registration, another portion grooved for top-level hierarchical master keying, and two other portions, one on each side of the blade, for further master key variations and different combinations. One of the two further sections being curvilinear and the other rectangular or angular cuts.

The lock cylinders art is requiring higher and higher security and there is a need in the art for the development of a shape or profile of a cross section of key and corresponding shape of the keyway in the cylinder plug to accommodate a hierarchical lock providing high security. The shape of the keyway is the first barrier that rejects or filters an unauthorized key in attempt to operate the lock cylinder.
There is only a finite space in a lock cylinder plug that can be occupied by the key and that space must be structured to allow for the maximum number of unique keyway shapes to be able to develop lock systems of adequate size. In large modern lock systems it is usual to arrange the structure of the keyways in a manner so that at least three levels of a hierarchical system can be provided, with one master key blank at the top level of the system, some sub-master key blanks at a medium level and several change key blanks at the lowest level of the hierarchical system. A new key section design must be different from prior key sections so that the key blanks can be controlled by the manufacturer and the end user can benefit from the security offered by the exclusivity of this key control via the key blanks.
Unique key profile shapes provide for additional protection against unauthorized key copying. Most key blanks of the generally flat rectangular key profiles are manufactured with single pass formed milling cutters that shape the side of the key blank. The axis of rotation of the cutter is held parallel to the side of the blade. Keys using an undercut groove profile require additional form cutting on specially designed machines that are usually not available at commercial duplicator operations and thus the blanks are more difficult to copy or counterfeit.
Early in the development of lock cylinders, it became apparent that there were specific parameters that affected the size of the lock cylinder systems that could be developed and that there were many design factors that influenced the wear of the key and the cylinder and thus the longevity of the system. Key blanks were designed with these parameters in mind. Representative examples of the prior art include the following:
In U.S. Pat. No. 0,263,244, Taylor discloses a key blank design that offers an economically simple solution to the problem of having a key that moves too freely in the keyhole. This offers a very minimal keyway shape in the plug and key profile in the blank.
In U.S. Pat. No. 0,420,174, Taylor teaches a unique but limited master keying technique that uses a Y shaped key section in a plug that allows two differently shaped key profiles to contact their own areas of the non rotating tumbler pins.
In U.S. Pat. No. 0,567,305, Donavan discloses a method of expanding the number of key sections, thus increasing the available size of lock systems, by dividing the key blank height into various areas and using consistent warding techniques at these locations to develop hierarchical keyways or key profiles. This increases the system size of pin tumbler cylinders. The bittings of one key can be repeated on a different key blank, configured with a different key profile, and the cylinders into which these individual keys fit can also be operated by a higher level key designed to insert into both of the keyways.
In U.S. Pat. No. 0,608,069, Noack discloses an arrangement of key section warding that provides improved wear on the key and the key contact area on the tip of the locking pins. In addition it provides a narrow cross sectional width under the bitting area, thus making it difficult to manipulate pick tools under the tumbler pins.
In U.S. Pat. No. 3,499,304, M. Noujoks teaches a method of designing key section warding where both faces of the keys are provided with alternating ridges and grooves. It utilizes a master key blank that has all the grooves of the series but not the ridges, while the key blanks of a lower hierarchical level have varying ridges.
In U.S. Pat. Nos. 4,168,617 and 4,368,629, Prunbauer discloses more methods of designing key section warding where the master key will fit into the subordinate keyways but the lower keys will not fit into the master keyways. In one embodiment, the ridges and grooves defining the key section are of a rectangular cross-section shape, and the outwardly projecting variable ridge on the subordinate key extends laterally beyond any of the other variable ridges. The subordinate key is thicker at its further ridge than the master key is at any location. In another embodiment the master key is formed of a zigzag shape, that is with its opposite sides formed of a plurality of planar facets each of which is substantially parallel to a respective planar facet on the other side.
In U.S. Pat. No. 4,416,128, Steinbrink teaches another unique method of designing key sections where the longitudinal grooves on both sides of the key blank are formed with bottom faces that lay substantially along the arc of a circle.
In U.S. Pat. No. 4,653,298, Tietz discloses a method of designing master key section warding that incorporates an invariable or family profile near the bitting area on the blank, and the variations defining the individual key sections are located near the spline or bottom edge of the blank. Additionally there are at least two profile formations that cross a center line in the key blank, one ridge is extending beyond the surface of the blank, and the variations are made with longitudinal grooves having rectangular cross sections.
In U.S. Pat. No. 4,683,740, Errani illustrates a key section design that has a undercut groove shape making it very difficult to manipulate a pick tool in the keyway of the plug. The undercut groove is formed by means of cutters having their rotational axis inclined in relation to the sides of the key blank.
In U.S. Pat. Nos. 5,715,717 and 5,809,816, Widen teaches some very specific methods of designing key sections using a three sided undercut groove located closest to the bottom edge of the key blank and extending inwardly inclined towards the bottom of the key blank, or using an undercut groove with a substantially flat surface which is inclined towards the groove bottom surface.
In U.S. Pat. No. 6,145,357, Stefanescu teaches a method of designing master key section warding that utilizes a key blank with a T-shaped cross sectional area with all the profile ribs having specific curvilinear cross sectional contours, with rounded front and flank portions.
In U.S. Pat. No. 6,851,292, Kruhn discloses a method of designing lock and key warding that incorporates specific perpendicular groove surfaces on one side of the key section, and slanting surfaces on the other side that are positioned in a relationship designed to trap, or limit the motion of a picking tool inserted into the key way.
While the prior art has developed usable key sections, they fail to maximize the area of the plug and do not allow for the development of many large master keying systems.


A speed stabilization apparatus for use in a two shaft gas turbine is disclosed which includes a speed detector for detecting a rotational speed of a driving shaft of a turbine for driving a generator, a governer for controlling the amount of fuel supplied to a cumbustor, a plurality of delay circuits for providing load charging delay signals after predetermined time periods from when load charging commands are generated, and a forcible fuel supply control circuit. The governer usually controls the amount of fuel to the combustor in accordance with the detected speed signal from the detector so as to stabilize a rotational speed of the generator. When a load charging command is generated, the forcible fuel supply control circuit causes the governer controlling such that the full amount of fuel in supplied to the combustor. After the predetermined time duration from that, the corresponding charging load is connected to an output of the generator.

1. Field of the Invention:
The present invention relates to a speed stabilization apparatus for use in a two shaft gas turbine, and more particularly to a speed stabilization apparatus for use in a two shaft gas turbine which can improve load charging dip characteristics; that is a momentarily reduction of a rotational speed of a generator when a charging load is additionally connected to an output of the generator.
2. Description of Prior Art:
A well-known two shaft gas turbine employs a compressor driving shaft connected to a compressor driving turbine for driving a compressor, and a load driving shaft connected to an output turbine for driving a generator which is a load of the turbine, wherein these shafts are driven independently. Such a two shaft gas turbine usually incorporates a governer as a speed stabilization means. The governor is so designed that it responds to a rotational speed signal representing a rotational speed of the load driving shaft, and opens a fuel valve by a suitable degree when the rotational speed of the load driving shaft is lowered, so as to increase the amount of combustion gas supplied to the turbine from a combustor thereby causing an increase in the speed of the turbine, while when the rotational speed of the load driving shaft is increased it closes the fuel valve by a suitable degree so as to reduce the amount of combustion gas, thereby causing a decrease in the speed of the turbine. In this manner, the governer can stabilize the variation of the rotational speed of the generator resulting from a change in the electrical load to be connected to an output of the generator, and hence the output frequency of the generator can be stabilized.
According to the generator driven by the two shaft turbine provided with a speed stabilization apparatus comprised of the conventional governor mentioned above, since the compressor driving shaft is in principle independent of the load driving shaft, if a basic load normally charged to the generator is light, the compressor driven by the compressor driving shaft is caused to rotate at a speed much below that of the output turbine for the generator driven by the load driving shaft the speed of which is directly regulated by the governer so that the rotational speed of the generator is maintained at a level equal to that of the generator charged a rated load, whereby a highly efficient operation may be ensured at the time of light loading.
Conversely, when a large amount of load is additionally charged to the light basic load, the governer is activated to regulate the speed in response to the reduction of the rotational speed of the load driving shaft. In this case, since the compressor is rotated at a low speed and little air is supplied from the compressor to the combustor, even if the fuel valve is opened quickly, the combustion gas will not be actively supplied from the combustor so quickly. Thus, the rotational speed of the load driving shaft cannot be immediately returned to the previous higher speed and as a consequence a load charging dip may be caused in the rotational speed at the time of high load charging.
It is conceivable, in order to solve this load charging dip problem, to employ a single shaft gas turbine adapted to drive a compressor and a generator with one shaft. According to the monoaxial gas turbine, since the compressor is driven by the same driving shaft the rotational speed of which is governed to be at a constant and fixed speed even against a light basic load, and thus the compressor will not rotate at a reduced rotational speed at the time of light loading, an immediate response of the compressor may be secured and no or little load charging dip will be experienced. On the contrary, however, a high efficiency under a light basic load or partial load charging, cannot be anticipated. In view of the contradictory problems in terms of immediate response and high efficiency with regard to the two shaft gas turbine and the monoaxial gas turbine, there has been a demand for a speed stabilization apparatus for a two shaft gas turbine which is capable of simultaneously solving both the above problems.

Speed stabilization apparatus for two shaft gas turbine