A metal oxide semiconductor gas sensor and a method for production thereof. The sensor comprises a sensor-active metal oxide thin layer applied to a substrate, in contact with at least one electrode. The sensor-active metal oxide thin layer comprises a chromium/titanium oxide (CTO) layer with a thickness of about 10 nm to about 1 μm. The chromium and titantium layers are applied over each other using thin layer technology and are subsequently tempered.

The invention pertains to a metal oxide semiconductor gas sensor, which has a chromium/titanium oxide (CTO) layer as a sensor-active thin metal oxide layer, and a process for its manufacture.
Metal oxide semiconductor gas sensors are known, and are used in many sectors for detecting particles in the air. Semiconductor gas sensors generally comprise a sensor-active metal oxide layer that is arranged on a substrate, whereby the sensor-active layer is connected to at least one electrode. The earlier sensors are preferably constructed in such a way in this regard that contact electrodes are applied directly to an inert support. The sensor-active layer is then deposited onto the contact electrodes. An integrated heating unit is usually provided in order to adjust to the operating temperature, whereby this heating unit can be arranged, for example, on the rear side of the substrate. A thin SiO2 layer, for example, is provided for passivation purposes both for the contact electrodes and for the heating unit, whereby this thin silica layer can be applied directly to the substrate. In this regard, use is also often made, in a controlled manner, of promotors/catalysts for specifically activating a gas reaction at or on the surface. Sensors that have been modified in this way are used for a plurality of gases.
As far as the sensor-active layer is concerned, it is also known that it can be applied by means of thin layer technology. A sensor array with metal oxide semiconductor gas sensors is described in DE 44 24 342 A1, whereby these sensors are operated in the form of resistance elements, and whereby the sensor-active layer is a SnO2 layer that has been applied by means of thin layer technology. Further thin layer gas sensors of this type are also described in DE 197 10 456.8 A1 as well as in DE 197 18 584.3 A1. The following are recommended as metal oxide materials, which are suitable for thin layer technology, in the documents that are described above: SnO2, TiO, ZnO, FexOy, ZrO2, Ga2O3, CuO, InO3, and WO3.
It is also known from the prior art that use can be made of a layer that comprises a mixed oxide, namely one comprising chromium/titanium oxide (CTO), as a sensor-active layer for gas sensors. However, the manufacture of such sensors, i.e. a gas sensor in which use is made of a mixed oxide of the type described above as a sensor-active layer, has been possible thus far only in the thick layer technology sector.
A disadvantageous feature in this connection is that sensors, which have a CTO layer as a sensor-active layer, do not have any structuring possibilities in the μm region. Thus these gas sensors cannot be introduced, in the form of micro-electronic components, into appropriate circuits.
Starting from here, the problem for the present invention is to propose a metal oxide semiconductor gas sensor that has a mixed oxide as a sensor-active layer, so that it can be introduced, in the form of a micro-electronic component, into appropriate circuits.
A further problem is to indicate a suitable process for the manufacture of such metal oxide semiconductor gas sensors that have a mixed oxide as a sensor-active layer.
The invention therefore pertains to a metal oxide semiconductor gas sensor that has a chromium/titanium oxide layer as a sensor-active thin metal oxide layer. Such a gas sensor, which has a thin CTO layer as a sensor-active layer, has not previously become known from the prior art. Thus now, for the first time, gas sensors with CTO layers can also be incorporated, in the form of microelectronic components, into appropriate circuits. The thin layer sensor with the CTO layer in accordance with the invention has a layer thickness of 10 nm to 1 μm. The layer thickness is preferably selected in such a way that it lies in the range from 100 to 500 nm. Thus the sensor in accordance with the invention involving thin layer technology differs clearly from the previously known sensor of WO 01/38867 A1 that also has a CTO layer as a sensor-active layer because its morphology derives from the sector involving thick layer technology. Thus utilization for micro-electronics is not possible.
An essential aspect of the sensor in accordance with the invention is that the mixed oxide is present in the form of a single phase material that has the corundum structure, whereby this phase advantageously corresponds to that of sensors involving thick layer technology. The gas sensor with the thin CTO layer in accordance with the invention can hereby have up to 40 atom-% of titanium in the cation sub-lattice.
The gas sensors in accordance with the invention with thin CTO layers have specific layer resistances of approximately 10 kΩ to 10 MΩ, and preferably several multiples of 100 kΩ, at operating temperatures of approximately 350° C.
As previously, the CTO layer of the gas sensor in accordance with the invention can of course contain catalysts or promoters that are already known from the prior art.
In the case of the substrates, use can likewise be made of all substrates that were previously known for gas sensors of the prior art. Use is preferably made of silicon as a substrate with SiO2 as an insulator along with Al2O3 or quartz glass.
The thin layer gas sensor with the CTO layer in accordance with the invention can also have a passivation layer that is arranged between the substrate and the CTO layer. Use is preferably made of SiO2 as a passivation layer for the gas sensor in accordance with the invention. The passivation layer can have a thickness of 100 nm to 1 μm.
The thin layer gas sensor in accordance with the invention is not subject to any restrictions whatsoever in regard to the electrode arrangement. In principle, all structures, which are previously known from the prior art for the production of electrodes, can also be used for the thin layer gas sensor in accordance with the invention. It is preferable in this regard if the sensor is constructed in the form of a contact pad on the substrate. Reference is made to DE 44 24 342 C1 in regard to the design of this contact pad and the corresponding materials. Reference is made exclusively to the disclosed contents of this document [translator: i.e. for the purpose of the present patent document as well].
The invention also comprises the possibility of connecting together several sensors to give a sensor array. In order to do this, reference is also made to the aforementioned DE 44 24 342 C1 and to DE 197 10 4568 A1 and DE 197 18 584.3 [translator: i.e. for the purpose of the present patent document as well]. The possibilities that are pointed out therein for constructing sensor arrays and the structuring thereof also apply to the gas sensor that is described above.
The invention also comprises a process for the manufacture of the metal oxide semiconductor gas sensor that is described above.
An essential aspect in the case of the process in accordance with the invention is that the metal layers are applied one above the other by means of thin layer techniques that are known as such, and that tempering then takes place. It is hereby immaterial which layer is applied first. The chromium layer can be applied to the titanium layer or the titanium layer can be applied to the chromium layer. Surprisingly, the inventors have been able to show that inter-diffusion, reaction, and crystal growth take place simultaneously when the metal layers are applied one above the other as in the above process. It is to be emphasized in this regard that the process in accordance with the invention leads to a single phase material having the corundum structure.
Thin layer processes such as thermal evaporation or sputtering can be used for assembling the layers. Basically, processes such as MOCVD and MBE-derived methods are also extremely suitable.
In this connection, it is immaterial for the thermal processes whether the metals are transformed into the vapor form from suitable evaporator sources by means of resistance heating, or whether the metals are transformed into the vapor phase via the use of electron beam evaporators. For sputtering processes, use can be made of processes with individual metal targets as well as those with suitable mixed targets. Simple and variable process implementation is preferably achievable via individual targets.
The selection of the individual layer thicknesses relative to one another is hereby essential both for pre-adjusting the chromium to titanium ratio and for the formation, in accordance with the invention, of the homogeneous mixed oxide. The layer thicknesses of the individual metal layers preferably lie in the range from 2 to 200 nm, and preferably in the range from 5 to 75 nm.
Appropriate layer thickness ratios for sensitive layers can hereby be derived directly from the molecular data and the density of the metals. Thus it is possible to cover the concentration range up to 40 atom-% of titanium in the cation sub-lattice, whereby this concentration range is important for sensitive layers.
The layer thickness ratios are limited by the necessity, by means of a subsequent tempering process, of ensuing homogeneous intermixing of the metals via inter-diffusion, and of ensuring complete oxidation to give CTO via oxidative implementation of the tempering process. The coating process itself has to be carried out in such a way that the coating adheres to substrates that are suitable for sensor applications. The coating rates are hereby in the 10-20 nm/minute range. The overall layer thicknesses are governed by the overall resistances in the 10 to 100 Ω range that are to be achieved at the usual temperature of these layers when used as gas sensors. These are temperatures of up to 500° C.
A further special aspect of the process in accordance with the invention is the tempering process, whereby this is a low temperature process in comparison to the temperatures of up to 1300° C. that are necessary for the formation of homogeneous mixed crystals. This low temperature process, which is suitable for temperatures below and up to 850° C., is possible because—in comparison to the prior art, and as a result of the above designated deposition process—significantly closer molecular contact is present between the participating partners than in the case of a conventional solid state reaction between the prescribed and also nano-scale proportions of the separate oxides Cr2O3 and TiO2. The essential difference relative to the prior art in regard to the formation of the CTO resides in the aspect that inter-diffusion, reaction, and crystal growth take place simultaneously here. The tempering times are approximately 12 hours. The layer thickness increases during tempering. Tempering can take place both under controlled atmospheres in a conventional diffusion oven and also via rapid thermal annealing equipment.
The process is successfully demonstrated, on the one hand, by means of adhesion studies via temperature shock treatment in liquid nitrogen (detachment of layers that are not in accordance with the invention) and, on the other hand, by means of electron microscopy, preferably by means of scanning electron microscopy (SEM) combined with energy dispersive x-ray analysis (EDX), whereby the latter method is for determining the elemental composition. The crystal structure is successfully demonstrated by means of conventional Θ/2Θ x-ray studies. Within the limits of detection, these show none of the metals and exclusively single phase material having the crystal structure that is expected: i.e. the corundum structure.
An essential aspect of all the forms of embodiments with the above designated methods is that, following the tempering process, the CTO has the same advantageous properties as the CTO of the prior art in terms of structure, electrical properties, and sensitive properties.
In forms of embodiment that are typical, the tempered layers, when in a suitable sensor layout (e.g. DE 44 22342 C1, DE 197 10456 C1, DE 197 18584 C1, DE 199 44 410 A1), have specific layer resistances of approximately 10 Ω to several MΩ, and preferably several multiples of 100 kΩ at operating temperatures of approximately 350° C.
FIG. 1 shows the basic structure, in schematic form, of a sensor in accordance with the invention. FIG. 1 does not hereby contain the necessary electrodes for operating the sensor.
The sensor in accordance with FIG. 1 comprises a silicon substrate onto which a 1 μm thick SiO2 layer has been deposited. The CTO layer has a thickness of several multiples of 100 nm, and was deposited via the process in accordance with the invention as explained above in the specification. In this case, FIG. 1 merely shows a possible form of embodiment by way of example. In exactly the same way, it is also possible to build up the layer structure on other substrates, such as Al2O3 in its usual morphological forms including sapphire, that are suitable for the particular use in question of the gas sensor.
FIG. 1 hereby shows the layer structure in the form of an individual sensor. As already stated above in the specification, the invention also naturally comprises all other forms of embodiment in which the individual sensor is serially connected in the form of an array. In this regard, reference is explicitly made [for the purpose of the present patent document as well] to the disclosed contents of DE 44 22 342, DE 197 10456 A1, DE 197 18 584 A1, and DE 199 44 410 A. The forms of embodiment that are described therein in the form of an array are also possible with the sensor in accordance with the invention. A preferred form of embodiment comprises an array with SnO2 with and without catalyst[s], with WO3 with and without catalysts, and also with V2O5 with and without catalysts primarily formed for oxide layers using thin layer technology. In exactly the same way, combinations are also possible in the form of an array on a chip with sensitive layers that have been applied using conventional thick layer techniques.
Next, FIG. 2 shows a SEM photograph of a thin layer CTO surface in accordance with the invention. The surface in accordance with FIG. 2 was tempered in synthetic air at 900° C. Crystals of the size order of 50 nm to 200 nm can be seen that are connected to the various faces. As can be seen from FIG. 2, the CTO surface has a uniform structure both in a transverse fracture and in the grains and in the distribution of grain sizes on the surface. The patent applicant has been able to show via experiments that such layers withstand the adhesion test (LN2 shock test).
Next, FIG. 3 shows an example of characteristics that are typical of a layer in accordance with the invention.
FIG. 3 hereby shows the change in resistance as a function of time in combination with a sensor layout in accordance with DE 197 18 584 when being impacted with various target gases in synthetic air (50% relative humidity) at an operating temperature of 420° C.
The high sensor sensitivity in the case of being impacted with ammonia is to be emphasized in this connection. The slow adjustment to the basic resistance following impacting with ammonia is not engendered by the sensor in this case. Hence only the desorption properties are shown of the measurement equipment that was used here.
In addition to these typical characteristics, the layers in accordance with the invention are also characterized by a typical low sensitivity to humidity at various ammonia concentrations.
FIG. 4 shows the influence of the relative atmospheric humidity at various ammonia concentrations on the resistance of a CTO sensor at an operating temperature of 380° C. In this typical example, the ammonia concentration is 0-100 ppm, and the relative atmospheric humidity has been varied from 0-70%.
The typical properties with respect to conventional target gases, such as methane, CO, NO, H2, and ammonia, combined with the low sensitivity to moisture permits additional forms of embodiment together with a moisture sensor in an array. Such a combination results in the possibility of quantitatively determining the target concentration via the combined sensor reaction comprising sensitivity to the corresponding targets together with low moisture sensitivity by means of subsequent evaluation using a second exclusive[ly] moisture sensitive sensor.

Chromium/titanium oxide semiconductor gas sensor and method for production thereof

Fraunhofer-Gesellschaft zur Forderung der Angewandten Forschung e.V.


Objects to be achieved by the invention are to provide a nanobio device in which cultured cells are organized at a high-level in a state near in vivo, and to provide a method of using the nanobio device of imitative anatomy structure. The nanobio device of imitative anatomy structure of the invention is obtained by manufacturing a substrate with a bio-compatible substance and arranging a plurality of types of cells thereon in a desired array. A method of manufacturing a nanobio device in the invention includes a step of manufacturing a substrate for a nanobio device by a micromachine processing technique and a step of arranging a plurality of cultured cells on the substrate in a desired array with laser optical tweezers.

1. Field of the Invention
The present invention relates to a fusion of a technique in a biotechnology and a nanotechnology that realizes a highly integrated substrate device and, more specifically, to a technique for manufacturing a nanobio device in which a group of cells are arranged in array according to a rule which is formed by imitating a certain anatomy structure.
2. Description of the Related Art
In the field of biotechnology in recent years, individual cell can be controlled freely owing to improvement of laser trapping technique and the like, and a shape having dimensions or design according to an intended use can be processed on a substrate since high-integration degree or high-speed degree of the substrate device is enhanced due to recent development of nanotechnology. This technique has reached a level which intends to manufacturing of a nanobio device in which a group of cells are arranged in array according to a rule obtained by imitating a certain anatomy structure. In other words, organization of a cultured cell on a nanodevice in a high level which is substantially in vivo state, which has been believed to be difficult in the related art is in the course of realization owing to the fusion of these technologies. Consequently, it can be expected as an effective tool only in manufacture of material for regeneration medicine, but also in analysis of intercellular action which has been difficult to be figured out in vitro. On the other hand, exhaustive analysis such as transcriptome analysis using a DNA micro-array method or proteome using two-dimensional electrophoresis and a mass spectrograph is utilized in various fields of medical science and biology, and a high throughput analysis attracts attention. It is because not only understanding of the molecules in individual level, but also exhaustive understanding of diversification of molecular mechanism in a network of cells by the high-throughput analysis is required as the entire gene array retained by each living organism is made known by a genome project or a DNA project. Such tendency of new technology is in the course of developing an age of analysis not only by gene expression or an interaction of proteins, but also on a level of living cells by using a system of nanobio device combined with the high-throughput approach, and establishment of anew system as a successor of a biological test and application to a medicament screening and so on are now in the level of being promised.
Regeneration medicine is one of the fields of research which gets the highest attention recently. The prime reason is that it is expected as a medical practice in a new century which supplements serious lack of transplant internal organs. However, it is still in the level of cell transplant treatment at the present moment, and is not in the level of regenerating the internal organ itself. The reasons why regeneration of the internal organs is not realized are as follows. The internal organ has a regular, but very complicated structure such that the internal organ is composed of a plurality of cells, and that a vascular network for supplying nutrition and oxygen is present therein. Therefore, it has been considered that even though it is possible to provide individual cells, it is very difficult to build an internal organ itself therefrom. In other words, with the conventional technology, it is extremely difficult to arrange and constitute an organization of each internal organ by controlling the cells.
However, owing to innovation of laser manipulator technique and development of micro-fabrication technique in the field of nanotechnology in recent years, the cell itself is now able to enjoy benefits of nanotechnology sufficiently. Accordingly, although it is still far from the level at which the internal organ itself can be regenerated at the present moment, it is now possible to arrange cells as desired in a state of segments of an internal organ on an artificial substrate. Therefore, if the substrate having cells arranged thereon can be built using this technique, a three-dimensional internal organ structure can be manufactured by laminating the same into a plurality of layers. Furthermore, if the substrate can be built with a bio-compatible substance such as collagen or hyaluronic acid, an adverse reaction with respect to the cells can further be reduced, and hence manufacture of an internal organ unit that can be transplanted will also be possible in future in combination with a technique of revascularization.
As a source to be used actually for building an internal organ, a systematic stem cell such as a bone marrow cell or an embryonic-stem cell (ES cell) is considered as one of examples. Although the systematic stem cell has a problem such as cell fusion, there is an advantage such that immunological rejection may not occur in theory since it can be taken from an adult and since it is a cell of his/her own, which is one of factors fascinating for building an internal organ. On the other hand, in a problem regarding the embryonic-stem cell, a way to practical use in the field of medical practice is now being explored since a gene relating to formation of a teratoid tumor, which has been an obstacle for transplantation, is now identified and, as regards immunological rejection, a clone embryo technique for transplanting a somatic nucleus of a patient to a fertilized egg and establishing the embryonic-stem cell is enabled. Further development of research on such stem cells to enable foundation of a system in which these stem cells can be supplied as a source (individual cells) for building an internal organ is required for the internal organ regeneration by means of nanotechnology.
[Non Patent Document 1] Oode K, Furuya T, Harada K, Kawaguchi S, Yamamoto K, Hirano T. Sasaki K. "The development of a cell array and its combination with laser-scanning cytometry allows a high-throughput analysis of nuclear DNA content" Am J Pathol. 157(3) pp. 723-728 September 2000.
[Non Patent Document 2] Teratani Ko, Ochiai Takahiro, "Stem Cell, ES cell—Mesenchymal Stem Cell" Regeneration medicine Vol. 3, No. 4 pp. 126-133, 2004)

Nanobio device of imitative anatomy structure


Each upright of an electronic, especially telecommunication equipment rack comprises an outer profile and an inner profile delimiting a hollow interior volume used to run connections along equipment supported by said uprights. The profiles are such that the interior volume has in the heightwise and depthwise directions an opening accessible from the front side of the rack providing easy access to the connections along all of their path between the points at which they enter and leave the interior volume.

1. Field of the Invention
The present invention concerns the general construction of an electronic, especially telecommunication equipment rack.
2. Description of the Prior Art
In equipment of this kind the printed circuit boards carrying the basic electronic components and constituting the equipment are usually grouped together in structures called subracks in which they are usually disposed vertically, these subracks being in turn grouped together in structures called racks in which they are usually disposed horizontally.
The racks are usually of the type comprising two uprights supporting the subracks and each having a shape designed to constitute a hollow interior volume for passing connections internal to the rack along the subracks from an entry point at which the connections are fed into the rack and an exit point where they leave this volume to run transversely to their destination point on the subrack, this interior volume being open to provide access to the connections from one side of the rack, called the access side, from which an operator can access the subracks.
The remainder of the description concerns only one upright per rack and therefore only one interior volume, but it is obvious that the rack comprising two identical uprights has a second interior volume identical and symmetrical to that described.
The destination points for the same subrack are usually grouped together on a device called a connection strip and comprising, for example, on the posterior part of the subrack a heightwise extension of the backplane printed circuit board to which are fixed and connected the half-connectors providing connections to these destination points. Mechanical and electromagnetic protection is provided by the appropriate adaptation of the mechanical structure of the back and top of the subrack. The resulting strip is set back from the subrack front panel and therefore provides a space between two superposed subracks providing access to the exit points and to the connectors.
This type of rack is usually of substantially parallelepiped shape, having upper and lower sides, two lateral sides and front and rear sides, one of the last two sides constituting said access side. The interior volume is also usually of substantially parallelepiped shape, fitting within the aforementioned parallelepiped and consequently having a height and depth less than or equal to those of the latter and a width very much less than that of the latter. In the following the expression "first side" refers to that of the lateral sides of an interior volume that is inside the rack, the term "second side" refers to the front or rear side of an interior volume which is accessible via the access side of the rack and the terms "third side" and "fourth side" respectively refer to the sides of an interior volume respectively facing said first and second sides.
The present invention is more particularly concerned with the problem of access by an operator to said connections, especially those conveying signals to be processed by the equipment in the rack, which may need to be worked on, possibly after installation of the equipment, for example to modify the wiring of these connections to said destination points or to replace a faulty connection. More generally, it must be possible under normal operating conditions to solve problems arising on any particular connection without disturbing or disconnecting a neighboring connection even for a minimal time interval. Given these conditions, it is essential that the operating personnel has easy and individual access to each of the various connecting cables of a rack.
Until now, this problem has usually been solved in the manner now to be described with reference to FIGS. 1 and 2 showing two prior art embodiments of racks of the above type.
FIG. 1 shows a typical rack of this type in schematic plan view. In this example an upright 1 delimits an interior volume 2 symbolically represented by the crossed dashed lines and whose depth is similar to that of the rack 3, the difference in depth being used to fix subracks 4 to the uprights. Such fixing, symbolically represented at 5, uses the second side 6 of this interior volume.
The interior volume has an opening occupying depthwise the majority of the first side of the interior volume, said opening 7 containing said exit points and the solid parts 8 and 9 of this side increasing the stiffness of the upright. A drawback of this type of upright is that it considerably complicates access by an operator to the interior volume. Assuming that work must be carried out without disturbing or interrupting the operation of the equipment whose connection do not require any work to be carried out, in other words excluding any possibility of taking out a subrack to facilitate such access, considerable skill and dexterity are required to guide the connections along the length of this interior volume from the entry point which is usually on the upper or lower side of the interior volume and at which the connections are fed into the rack and the exit point situated in this case on said first side where the connections leave the interior volume to be run transversely to their destination point on the equipment via a connecting strip as previously explained. Guidance is here rendered difficult by the fact that the interior volume is usually extremely narrow to leave the maximum space available for electronic equipment inside the rack.
FIG. 2 shows another example of this type of rack, also in schematic plan view.
In this example an upright 10 delimits an interior volume 11 symbolically represented by crossed dashed lines whose depth is substantially equal to half that of the rack 12. The subracks 13 are fixed substantially halfway along the depth of the rack to the first side 14 of this interior volume using an intermediate spaced 14. The interior volume is open on its second side 16 to provide access to said exit points.
In the present example of access to the interior of the rack from its front side, all the destination points of said connections are again disposed on a strip at the rear of the subrack and a space is left between two superposed subracks. A drawback of the type of upright used here is that it imposes a plurality of successive changes of direction on the path of said connections between the point at which they leave said interior volume and their destination point on said equipment, with one part of this path in particular situated perpendicular to said access side, rendering the stowage of these connections within the rack somewhat anarchic and difficult to carry out over this portion of the path.
An object of the present invention is to provide a rack structure for electronic, especially telecommunication equipment whereby the above drawbacks can be avoided.

Electronic, especially telecommunication equipment rack


A serial communications protocol is provided that has mandatory features such as an idle code feature and optional features such as an optional automatic lane polarity reversal feature and an optional automatic lane order reversal feature, an optional clock tolerance compensation feature, an optional flow control feature, and an optional retry-on-error feature. A user that desires to create a protocol-compliant integrated circuit design can either choose to include or to not include the optional features. Integrated circuits in which the optional features are implemented are able to perform the associated functions. Integrated circuits in which the optional features have not been implemented are not able to perform these functions, but can be fabricated using fewer circuit resources.

This invention relates to serial communications, and more particularly, to serial communications protocols having optional serial communications features.
Serial communications formats are often used in modern electronics systems. Serial communications can be faster than parallel communications, use fewer pins, and, particularly when differential signaling schemes are used, can have higher noise immunity.
It can be challenging to handle serial data streams at high data rates (e.g., at data rates above several Gbps). As a result, it is often advantageous to support high-speed serial data communications using multiple smaller serial data paths operating in parallel. These smaller serial data paths are often referred to as "lanes."
A number of functions are involved in controlling the operation of a successful serial communications link. These functions include link initialization, idle character generation, insertion, and deletion, clock tolerance compensation, flow control, and retry-on-error, etc. Serial communications protocols in which these functions are mandatory can become "heavy" and require a large amount of resources to implement on an integrated circuit. Serial communications protocols that do not support these functions do not require as many resources to implement, but can be inadequate for many communications tasks.

This patent is subject to a terminal disclaimer.

Serial communications control plane with optional features


A system for generating a time overcurrent curve from a set of time and current inputs. The overcurrent curve is generated by simultaneously finding four coefficients of a standard overcurrent equation. Two of the coefficients are found by successive approximation and two of the coefficients are found via a least squares fit approximation. After the coefficients are found, they are used in the standard overcurrent equation to produce a set of data points indicative of the overcurrent curve. The data points are transferred to an overcurrent relay for the detection of overcurrent conditions.

Current microprocessor-based overcurrent relays operate on standard time-overcurrent trip characteristics. Those standards evolved as the technology of relays progressed from the initial electro-mechanical relays to solid state relays to the current microprocessor-based relays. When overcurrent relays were first developed they employed electro-mechanical switching mechanisms to provide the required overcurrent protection. Such electro-mechanical switching mechanisms, such as induction-disk type relays, exhibited certain time response characteristics. Accordingly, as the electro-mechanical relays became entrenched in the industry, their characteristic time-overcurrent response characteristics became standardized, resulting in the development of generally accepted families of overcurrent curves. Subsequently, as overcurrent relay development progressed to solid state devices, the solid state devices were designed to emulate standard electro-mechanical like overcurrent curves. These standard overcurrent curves were likewise emulated by the microprocessor-based relays that followed the solid state relays.
The solid state devices that developed used a series of linear segments to emulate the non-linear characteristics of the electro-mechanical relays. U.S. Pat. No. 4,017,766 (Vercellotti et al.), issued in 1977, discloses a solid state overcurrent relay that purportedly emulates the standard overcurrent curves via a series of successive linear time-overcurrent segments. By concatenating the linear segments Vercellotti emulated the non-linear electromechanical overcurrent relay characteristics. In this way, all the benefits of solid-state devices were brought to bear on the relay arts while accepted standard performance characteristics were maintained.
Eventually, the overcurrent relay industry adopted microprocessor-based mechanisms that emulated the earlier solid state devices, but with the added flexibility gained by a microprocessor. For example, the microprocessor-based relay overcurrent response curves could be quickly and relatively easily changed by reprogramming the relay. That is, microprocessor-based relays employ linear segments to emulate non-linear time-overcurrent characteristics. However, the linear segments could be rather easily changed to provide different time-overcurrent characteristics. For example, by simply changing data points (i.e., line segmented points), a previously installed relay time-overcurrent characteristic is altered to accommodate changes in the system in which it is employed. As a result, the useful life of a relay was extended because it could adapt to changing characteristics of the circuit.
Eventually, ANSI standards emerged that provided a standard time-overcurrent equation representative of the time-overcurrent response curves used by microprocessor-based overcurrent relays. The current proposed ANSI standard equation, per Draft ANSI standard C37.112, is defined below: ##EQU1## where: t is the trip time in seconds;
M is a current ratio that is equal to I divided by I.sub.P ; PA1 I is equal to the expected input current; PA1 I.sub.p is equal to the pickup set point current (i.e., the relay current set point as is well know to those of ordinary skill in the art); PA1 A is selected for the desired curve slope characteristic and must be greater than zero; PA1 P is selected for the desired curve characteristic and must also be greater than zero; and PA1 B is selected for the desired time to trigger offset. PA1 M is equal to I divided by I.sub.P ; PA1 I is equal to the input current; PA1 I.sub.P is equal to the pickup set point current; PA1 A is selected for the desired curve characteristic and must be greater than zero; PA1 P is selected for the desired curve characteristic and must also be greater than zero; and PA1 B is selected for the desired curve offset.
Notably, the ANSI standard is asymptotic to the time axis. That is, as the value of M.sup.P approaches one, t approaches infinity. Many applications find this to be an undesirable characteristic. Accordingly, the ANSI equation has been modified to define a value of t when M.sup.P is equal to one. Many microprocessor-based relays employ the modified ANSI equation of the form: ##EQU2## where C is less than or equal to one and the other variables are the same as in equation (1). This equation is often referred to as the modified ANSI standard.
In some conventional microprocessor-based relays, the values for the coefficients A, B, C and P in equations (1) and (2) are provided by the user to a computer which then computes a set of data points representing linear line segments representative of the desired non-linear overcurrent curve. Those line segments are then communicated to the microprocessor-based relay.
The present inventor has recognized that the prior art systems require a user to know the coefficients representative of a particular non-linear curve; however, the coefficients are difficult to derive from a graphical representation. In fact, the inventor has recognized that the user may not have ready access to the coefficients. Thus, there is a need for a system and method for supplying overcurrent curve data to an overcurrent relay that overcomes the drawbacks of the prior art.

Method of configuring a microprocessor-based relay for use in overcurrent protection


A semiconductor memory device includes: a memory cell array region having a plurality of normal cell lines and a plurality of repair cell lines; a plurality of normal cell line selection units suitable for selecting the plurality of normal cell lines, respectively, in response to a local address; a plurality of repair cell line selection units suitable for selecting the plurality of repair cell lines, respectively, in place of normal cell line selection units corresponding to fail information of the local address; a fuse driving unit comprising a fuse array in which the fail information is programmed, suitable for disabling the normal cell line selection units corresponding to the fail information, and enabling normal cell line selection units unrelated to the fail information; and an address determination unit suitable for controlling the plurality of repair cell line selection units based on the fail information.

1. Field
Exemplary embodiments of the present invention relate to a semiconductor design technology, and more particularly, to a semiconductor memory device.
2. Description of the Related Art
Generally, semiconductor memory devices such as a double data rate synchronous dynamic random access memory (DDR SDRAM), have a large number of memory cells. Since the integration degree has increased with the development of process technology, the number of memory cells has further increased. When a fail occurs in any one of the memory cells, a semiconductor memory device having the memory cell must be discarded because the semiconductor memory device cannot perform a desired operation. Recently with the development of the process technology for semiconductor memory devices, a defect occurs only in a small number of memory cells. When a semiconductor memory device is discarded due to such a small number of defects, it is very inefficient in terms of yield. Thus, to solve such a concern, a semiconductor memory device additionally includes redundancy memory cells as well as normal memory cells.
A redundancy memory cell is provided to replace a normal memory cell in which a fail occurred (hereinafter, referred to as a "repair target memory cell"). Specifically, when the repair target memory cell is accessed during a read/write operation, the redundancy memory cell is accessed instead of the repair target memory cell. Thus, when an address corresponding to the repair target memory cell is inputted, the semiconductor memory device performs an operation for accessing the redundancy memory cell instead of the repair target memory cell hereinafter, referred to as a "repair operation"). The repair operation may guarantee a normal operation of the semiconductor memory device.
Generally, a redundancy circuit for the repair operation is provided in each of a plurality of banks included in the semiconductor memory device. The bank includes a cell mat having a plurality of unit cells, a row control region having circuits for controlling a row access, and a column control region having circuits for controlling a column access. The redundancy circuit may include a row redundancy circuit for storing a row address of a unit cell having a defect and a column redundancy circuit for storing a column address of a unit cell having a defect. The row redundancy circuit and the column redundancy circuit are included in the row control region and the column control region of the bank, respectively.
FIG. 1 is a block diagram illustrating a conventional semiconductor memory device for describing a repair operation of a row control region.
Referring to FIG. 1, the semiconductor memory device 100 includes a normal mat 110, a repair mat 120, an address latch unit 130, a normal word line selection unit 140, a repair word line selection unit 150, and a mat selection unit 160.
When an active command (not illustrated) is applied to the semiconductor memory device 100, a row address XADD applied from outside is compared with a fail address stored in the address latch unit 130, and a first repair word line select signal XHIT0 is generated when the row address XADD coincides with the fail address. The address latch unit 130 may include a plurality of latches 130_1 to 130_N that may compare the row address XADD with the fail address and generate a plurality of repair word line select signals. The address latch unit 130 may activate a first control signal NXKILL when all of the repair word line select signals are activated. At this tune, the activated first control signal NXKILL is transmitted to the mat selection unit 160 to deactivate a mat select signal MATENB. Thus, in response to the deactivated mat select signal MATENB, the normal word line selection unit 140 does not perform a word line decoding operation for selecting a normal word line within the normal mat 110, and the repair word line selection unit 150 performs a word line decoding operation for selecting a repair word line within the repair mat 120. The first repair word line select signal XHIT0 is transmitted to the mat selection unit 160 and the repair word line selection unit 150. That is, after the first control signal NKKILL which is used to determine whether the row address XADD applied from outside is identical to the fail address or not is generated, the mat selection unit 160 may operate in response to a bank select signal BKSEL. Therefore, tRCD (Row to Column Access Strobe Delay "RAS to CAS Delay") and tAA (Column Address Access Time) are delayed by a delay time of the first control signal NXKILL and the bank select signal BKSEL.
Although not illustrated, a column control region is configured in a similar manner to the row control region. That is, fail information F_DATA is stored in an address latch unit, and then compared with a column address inputted from outside so as to generate a plurality of signals, and the plurality of signals are used to generate a second control signal. When the column address coincides with the fail information F_DATA, the second control signal does not operate a normal column line selection unit for generating a column select signal. Similar to the row control region, after the second control signal is generated, which is used to determine whether or not the column address is identical to the fail information F_DATA, the mat selection unit may operate in response to a strobe signal. Thus, a delay time of the second control signal and the strobe signal inevitably occurs.
FIG. 2 is a timing diagram describing a repair operation of the conventional semiconductor memory device.
Referring to FIG. 2, when an address A applied after an active command ACT is identical to a fail address, the first control signal NXKILL is generated to determine whether or not a repair operation is required. Then, a repair word line Red.WL is activated in response to the bank select signal BKSEL to be applied afterwards. When an address B applied after a read command RD or write command WT is identical to a fail address, the second control signal NYKILL is generated to determine whether or not a repair operation is required. Then, a repair column select signal Red.YI is activated in response to the strobe signal STROBE to be applied afterwards. Thus, tRCD and tAA are delayed by a delay time t1 between the first control signal NXKILL and the bank select signal BKSEL and a delay time t2 between the second control signal NYKILL and the strobe signal STROBE.

Semiconductor memory device for performing repair operation


A thermal and magnetic trip unit for a multi-pole circuit breaker includes a thermal structure having a bimetallic element and one or more heater elements. Each of the heater elements and a portion of the bimetallic element is generally "U" shaped defining a conductive path which extends from one leg of the U to the other leg. The heater elements and bimetallic element may be configured in parallel to reduce the level of current flowing through the bimetallic element and thus increase the current level at which the bimetallic element will trip the breaker. Alternatively, the heater elements may be configured in series with the bimetallic element, by inserting electrical insulators between the bimetallic element and each of the heater elements and connecting the various "U" shaped elements using a connecting bus which connects the second leg of one element to the first leg of the next element. In this configuration, the thermal structure defines a coil having one turns for each heater element and the bimetallic element. This coil may be used to implement a magnetic trip structure by inserting one or two magnetically permeable yokes, each yoke surrounding one leg of the combined thermal structure. An armature is positioned to be separated from the yoke by a gap such that, when the armature is pulled toward the yoke, it will engage the trip unit. In addition, the trip unit includes a calibration and adjustment bar that allows the gap to be adjusted as well as the force exerted on the armature by a biasing spring. The calibration and adjustment bar also allows each pole of the circuit breaker to be independently calibrated.

It is common for circuit breakers to employ thermal and magnetic elements which trip the circuit breaker under various overcurrent conditions. The thermal component typically includes a bimetallic element which responds to relatively long duration overload conditions to trip the breaker when a specified current level is exceeded for a period of time. In a typical thermal trip unit, at least a portion of the current flowing through the breaker is channeled through the bimetallic element. The ohmic resistance of the bimetallic element causes it to generate heat in proportion to the square of the level of current flowing through the breaker. As the bimetallic element becomes warmer, it bends and, when it reaches a predetermined temperature, engages a trip mechanism. The trip mechanism releases a latch which holds the breaker contacts closed. When this latch is released, the breaker contacts open, typically responsive to a relatively strong force.
A typical magnetic tripping element includes an armature which is attracted by a magnetic field generated by a relatively high magnitude overcurrent flowing through the breaker. This magnetic field is concentrated by a magnetically permeable yoke which surrounds the conductor through which the current flows. When the armature is attracted to the yoke, it also engages the trip mechanism causing the circuit breaker to open. Both thermal and magnetic structures are used in a typical circuit breaker trip unit to enable the breaker to be tripped on a relatively low overload condition having a long duration and to trip quickly in response to a relatively high overcurrent condition.
It is desirable to be able to configure and adjust the current levels and current durations which cause a breaker to trip in order to customize the circuit breaker to a particular application. Typically, thermal and magnetic structures in circuit breaker trip units may be adjusted to accommodate a relatively narrow variation in current magnitude and current flow duration. These adjustments are made by changing the distance between the bimetallic element and the trip bar for a thermal element and by adjusting the separation between the armature and the yoke for a magnetic trip element.

Variable thermal and magnetic structure for a circuitbreaker trip unit


An apparatus for abrading or deburring a workpiece is provided and includes in combination a conveyor for moving the workpiece from a first position to a second position and at least two assemblies intermediate the first and second positions and opposite the conveyor for abrading one side of the workpiece in a plurality of directions. In an alternate embodiment of the invention, a third assembly may be provided which deburrs an opposite side of the workpiece as it is passed through the deburring assembly. The conveyor for moving the workpiece positively fixes the location of the workpiece with respect to the conveyor and translates the workpiece through the deburring assembly.

Historically, parts or components stamped from sheets or ribbons of steel were hand-ground to remove sharp edges and burrs produced during the stamping process. Later, with the advent of power equipment, workers individually removed sharp edges and burrs from the stamped products using grinding and wire wheels. Although the advent of the power equipment expedited the process, parts or components were still being worked on individually on a piece-by-piece basis by a worker in a factory.
Continued technological advances in machinery, stamped components of the same pattern or design were stacked in magazines wherein a shuttle would remove a part from an end of the magazine and slide the component along the surface of a grinding belt to deburr the surface of the component facing the grinding belt surface. Water would be sprayed on the components as they pass along the belt to act as a coolant and remove the swarf from the belt during the process. At the end of the process, the component was discharged onto a ramp where the component was then stacked manually by the operator so the components could be moved on to the next station.
A disadvantage with this process was that the shuttle placed no force on the component which was perpendicular to the direction of travel to ensure that the component had been fully deburred. Because the grinding belt ran in a direction opposite to the translation followed by the shuttle, occasionally the component would be rocked up on edge such that deburring occurred only along a portion of the surface rather than along the entire lower surface. This resulted in poor quality and the occasional need to reverse the orientation of the part in the magazine to deburr the side that was missed. Furthermore, occasionally components would slide under the shuttle, either causing a jam of the grinding belt and ultimate destruction of the belt, or colliding with the subsequent component and cause a disruption of the grinding process. Furthermore, the parts or components needed to be loaded in a magazine which required manual labor and reduced the efficiency and throughput of the components through the grinding machine.
Accordingly, there has been a long-felt yet unresolved need to produce a machine which efficiently and thoroughly deburrs the entire surface of a stamped product wherein the components are positively retained and moved through the grinding process and wherein the production rate is substantially uninterrupted as a result of an operator need to load magazines and the like. The assembly described below, and embodying the invention, satisfies this need.


A moving device assembly includes a moving device and a shield. The moving device is movable between a first position and a second position, to move a detector including a detection surface relative to an opposing member disposed opposite the detector. The shield shields the detection surface of the detector. As the moving device is at the first position, the detector is at a proximal position at which the detector is near the opposing member, and as the moving device is at the second position, the detector is at a shield position at which the detector is separated from the opposing member and the detection surface of the detector is shielded by the shield.

1. Technical Field
Exemplary aspects of the present invention generally relate to an image forming apparatus, such as a copier, a facsimile machine, a printer, or a multi-functional system including a combination thereof, and more particularly to, a moving device assembly that moves a detector toward and away from an opposing member such as an intermediate transfer belt employed in the image forming apparatus.
2. Description of the Related Art
Conventionally, known image forming apparatuses, such as a copier, a facsimile machine, a printer, and a multi-functional system including a combination thereof form test image patterns on a surface of an intermediate transfer member such as an intermediate transfer belt for detection of the density and the position of a toner image. Such image patterns are detected by a detector.
In order to enhance accuracy of the detector, the detector needs to be disposed near the surface of the intermediate transfer member on which the image patterns are formed. However, if the detector is disposed close to the intermediate transfer member, the surface of the intermediate transfer member may contact and damage a detection surface of the detector upon replacement of the intermediate transfer member.
In view of the above, there is known an image forming apparatus in which the detector is separated from the intermediate transfer member as necessary. Furthermore, in order to facilitate separation of the detector from the intermediate transfer member, the known image forming apparatus includes a moving device that moves the detector in conjunction with movement of a cover provided to the image forming apparatus.
Although advantageous, if the detection surface of the detector is exposed while the detector is separated from the intermediate transfer member and other components, the detection surface of the detector may easily come into contact with technicians replacing the intermediate transfer member and/or contaminated by foreign substances. Contamination of and damage to the detection surface of the detector degrade detection accuracy of the detector.

Moving device assembly and image forming apparatus including the moving device assembly


A tire air pressure abnormality warning device includes a transmitter for transmitting a signal of the air pressure of a tire measured by a pressure sensor, a portable device for opening and closing a door lock of a vehicle, and a vehicle-installed device for determining whether or not the signal from the transmitter indicates an abnormal air pressure of the tire and for driving the door lock by a signal from the portable device. The vehicle-installed device has a recording section for recording tire air pressure abnormality data. When the vehicle-installed device communicates with the portable device, it searches for any abnormality data from the recording section. If there is any abnormality data, it transmits a tire air pressure abnormality signal to the portable device. The portable device indicates a warning of abnormal air pressure of the tire by the tire air pressure abnormality signal using a warning indicating section.

1. Field of the Invention
The present invention relates to a tire air pressure monitoring system (TPMS) comprising a vehicle-installed device, a portable keyless entry device, and a tire air pressure transmitter, and, more particularly, to a technology for giving a warning when an abnormality in the air pressure of a tire occurs.
2. Description of the Related Art
According to a related technology, a tire air pressure abnormality warning device comprises air pressure sensors for detecting the internal air pressures of tires. Detection signals from the sensors are output from transmitters mounted to wheels, and a receiver in an automobile receives the output detection signals. When an abnormal air pressure of any tire is detected, a warning is given by a driver's indicator panel.
Japanese Patent No. 2716335 discloses a structure in which a receiver, which receives a door lock signal and a door unlock signal from a radio-wave key (operating key), in a vehicle receives an abnormality detection signal from a transmitter that indicates an abnormal state of a tire. It also discloses a technology in which, based on the tire abnormality detection signal, a first warning unit or a second warning unit is selectively driven in order to output a warning inside or outside the vehicle. In other words, by selectively giving a warning inside or outside the vehicle when an abnormality of a tire is detected, the warning is given in accordance with whether a person is in the vehicle or is not in a parked vehicle.
The related technology for giving a warning by a driver's indicator panel causes inconvenience to a driver because, after a warning has been given by the indicator panel, the driver must get out of the vehicle in order to check the actual air pressure of a tire. In particular, when an abnormality in the air pressure of a tire of a parked vehicle is detected, a person cannot confirm any warning unless the person gets into the vehicle and looks at or listens to the driver's indicator panel. Therefore, after confirming the warning, the person must get off the vehicle again and actually check the abnormality of the tire, thereby causing inconvenience to the person.
In addition, in the technology that is disclosed in the aforementioned document, although, when the driver is outside the vehicle, he can know that a tire abnormality has occurred by a warning that is directed to the outside of the vehicle, the driver cannot know that the abnormality has occurred when he is outside a range that allows him to hear the warning.

Tire air pressure abnormality warning device and method


A piston, having a first side subject to major thrust loading and a second side subject to minor thrust loading, is provided. The piston has a crown portion and a first and second pin boss portion depending therefrom. An axially extending pin bore is provided within the first and second pin boss portions. A first axially extending slot is provided within the piston pin bore on the first side. Additionally, a second axially extending slot is provided within the piston pin bore on the second side of the piston. The second axially extending slot is positioned closer to the crown portion than the first axially extending slot. The first and second axially extending slots are generally concave in shape.

Internal combustion engines may utilize pistons, which are mounted for reciprocal movement within corresponding cylinders. The mounting of a piston within a cylinder involves the use of a connecting rod having a lower end journaled to a rotatable crankshaft and an upper end similarly attached to a piston pin extending in a diametrical pin bore within pin boss portions of the piston. The piston pin in a typical piston is supported at its ends by the pin bosses such that the piston pin acts as a journal with the pin bore functioning as a supporting bearing. The upper end of the connecting rod engages the piston pin intermediate of its piston-supported ends, thus completing the connection of the piston with the rotatable crankshaft. The piston pin to pin bore interface is a highly stressed area requiring proper lubrication and design to ensure adequate performance and reliability of the piston assembly.

Piston having asymmetrical pin bore slot placement


Switches with passive bootstrap that can achieve good sampling performance are described. In one design, a sampling circuit with passive bootstrap includes first and second filters and a switch. The first filter filters an input signal and provides a filtered input signal. The second filter filters a clock signal and provides a filtered clock signal. The switch receives a control signal formed based on the filtered input signal and the filtered clock signal and either passes or blocks the input signal based on the control signal. The first filter may be a lowpass filter having a first corner frequency that is higher than the bandwidth of the input signal. The second filter may be a highpass filter having a second corner frequency that is lower than the fundamental frequency of the clock signal. The first and second filters may both be implemented with one resistor and one capacitor.

I. Field
The present disclosure relates generally to electronics circuits, and more specifically to switches.
II. Background
Switches are commonly used in various electronics circuits for various applications. For example, switches are widely used in mixed-signal integrated circuits to sample analog signals. Sampling switches may be implemented with various types of transistors such as metal oxide semiconductor field effect transistors (MOSFETs). A sampling MOSFET switch typically receives an analog signal at a source and a control signal at a gate, passes the analog signal if the switch is turned on by the control signal, and blocks the analog signal if the switch is turned off by the control signal.
The performance of a sampling switch may be characterized by an on impedance when the switch is turned on and an off impedance when the switch is turned off. Low-distortion sampling may be realized with a high off-impedance to on-impedance ratio in combination with moderate device parasitics. For a MOSFET switch, the on and off impedances are determined by the voltages of the analog signal at the source and the control signal at the gate of the switch. A particular change in voltage (e.g., more than 1 Volt) between the gate and source may be needed to achieve a high off/on impedance ratio with moderate device size for acceptable parasitics. However, as integrated circuit (IC) fabrication technology improves and transistor size shrinks, lower power supply voltage is often used to avoid oxide breakdown due to smaller transistor geometry. With the power supply voltages of modern scaled semiconductor technologies approaching 1 Volt, realization of high off/on impedance ratio for good sampling performance becomes more challenging.
There is therefore a need in the art for switches that can achieve good performance even with low power supply voltages.

Switches with passive bootstrap of control signal


A method for coupling a keyboard base board with a keyboard base seat includes (a) a keyboard base board being formed with a plurality of through holes; (b) a mold being formed with a keyboard base board space and a keyboard base seat cavity corresponding to a keyboard base seat; (c) the keyboard base board being placed on the mold, and the mold being closed for injection molding; (d) a plastic material being poured from a concave trough through the through hole into the keyboard base seat cavity, the through hole of the keyboard base board and the keyboard base seat cavity being filled up with the plastic material; and (e) the mold being opened to take out the keyboard base board integrated with the keyboard base seat after cooling. The keyboard base board is formed integrally with the keyboard base seat for saving the working procedure.

1. Field of the Invention
The present invention relates to a method for coupling a keyboard base board with a keyboard base seat, and more particularly to a method for coupling the keyboard base board with the keyboard base seat direct.
2. Description of the Prior Art
Electronic products are to be changed with each passing day, in particular to computers. A keyboard is used as an input apparatus to a computer. There are different keyboards on the market. As shown in FIG. 1, a conventional keyboard structure comprises a base board A having a through hole, a keyboard base seat B coupled to the base board A, a support C engaged with the keyboard base seat B, a key unit D disposed on the support D. The keyboard base seat B is formed by injection molding singly, and then placed on the keyboard base board A for fusion one by one. This assembly method is complicated and needs a lot of time, increasing the cost. In order to reduce the assembly procedure and lower the cost, the inventor of the present invention has devoted himself based on his many years of practical experiences to the development of a method for coupling a keyboard base board with a keyboard base seat.

Method for coupling a keyboard base board with a keyboard base seat


A technique for finding malicious code such as viruses in an executable binary file converts the executable binary to a function unique form to which function unique forms of virus code may be compared. By avoiding direct comparison of the expression of the viral code but looking instead at its function, obfuscation techniques intended to hide the virus code are substantially reduced in effectiveness.

The present invention relates to computer programs and, in particular, to a computer program for detecting malicious programs such as computer viruses and the like.
In the interconnected world of computers, malicious programs have become an omnipresent and dangerous threat. Such malicious programs include "viruses" that are programs attached to other programs or documents that activate themselves within a host computer to self-replicate and attach to other programs or documents for further dissemination. "Worms" are programs that self-replicate to transmit themselves across a network. "Trojan horses" are programs that masquerade as useful programs but contain portions to attack the host computer or leak data. "Back doors" are programs that open a system to external entities by subverting local security measures intended to prevent remote access and control via a network. "Spyware" are programs that transmit private-user data to an external entity.
Methods for detecting malicious programs may be classified as dynamic or static. In dynamic methods, the suspected program is executed in a "sandbox". A sandbox is a safe execution area created in a computer that uses hardware and/or software to prevent the executing program from damaging interaction with the computer and to monitor attempts at such interaction, such as writing data outside of a predefined memory area.
Static detection does not require execution of the suspected program, but instead reads and analyzes the program instructions or "code" before it is executed. One "heuristic" detection technique looks for changes in certain program locations (normally the beginning and end of the code) where the virus is likely to be attached. A second "signature" detection technique checks for known virus-specific sequences of instructions (virus signatures) inside the program. Such signature detection is effective when the virus does not change significantly over time and when multiple viruses have the same signature.
Viruses may disguise their signature by encrypting themselves using a changing encryption key so that the encrypted viral code is always different. In this case, the signature detection may be directed to signatures in unvarying decryption programs. Another method of detecting encrypted viruses executes the programs in a sandbox until they are decrypted and then detects the decrypted virus using conventional static techniques of signature analysis. This technique requires frequent scanning of the in-memory image of the program while the program executes.
Many signature-detection systems may be defeated by relatively simple code obfuscation techniques that change the signature of the virus or the decrypting code without changing the essential function of the code. Such techniques may include changing the static ordering of the instructions using jump instructions (code transposition), substituting instructions of the signature with different synonym instructions providing the same function, changing the registers used by the viral code, and the introduction of code ("dead code") that does not modify the functionality of the virus.
Simple obfuscation may be countered by more complex search instructions, "regular expressions" that ignore simple dead code like no-op instructions at instruction boundaries. Also new signatures can be developed for each different obscured version of the viral code.
More complex metamorphic viruses may evade these more sophisticated signature detection systems by changing the obfuscation specifics as the virus is propagated. Such viruses may weave the viral code into the host program, also defeating the traditional heuristic approach to finding the virus.

Method and apparatus to detect malicious software


A method of providing a translation within a voice stream can include receiving a speech signal in a first language, determining text from the speech signal, translating the text to a second and different language, and encoding the translated text within the speech signal.

1. Field of the Invention
The invention relates to speech or voice translation systems.
2. Description of the Related Art
Spoken language is typically the most natural, most efficient, and most expressive means of communicating information, intentions, and wishes. Speakers of different languages, however, face a formidable problem in that communication is thwarted unless the language barrier is removed. As the global economy brings together persons of various nationalities, a forum is needed that provides efficient and accurate communication, which effectively eliminates the language barrier.
Translation systems have emerged to address this need. Presently available translation systems are capable of receiving a speech signal in a first language. Typically, the speech signal is provided to a speech recognition system to determine a textual transcript from the speech signal. The textual transcript then can be processed or translated into a different language, for example through the use of a translation system such as one using natural language processing. The resulting translated text then can be provided to another person or device as text or played through a text-to-speech system.

Providing translations encoded within embedded digital information

International Business Machines Corporation


An exhaust gas purifying catalyst wherein the catalytic activity can be recovered over a wide temperature range is provided. Also provided are a method for recovering an exhaust gas purifying catalyst, and a catalyst system for exhaust gas purification. The exhaust gas purifying catalyst is characterized by containing an oxide A containing an oxide (A-1) containing an alkaline earth metal and/or a rare earth metal and an inorganic oxide (A-2), and a noble metal B supported by the oxide A. This exhaust gas purifying catalyst is also characterized in that the weight ratio of the oxide (A-1) containing an alkaline earth metal and/or a rare earth metal to the noble metal B is from 1:10 to 1:500.

Conventionally, an exhaust gas purifying catalyst for use in an automobile or the like is known to include an oxide of alkali earth and rare earth supported by a noble metal such as Pt, Rh, Pd, and others.
While the above exhaust gas purifying catalyst processes an exhaust gas, sintering sometimes occurs to the noble metal (especially Pt), which results in deterioration in catalytic activity. In such cases, an oxidation treatment process and a reduction treatment process are applied after processing of the exhaust gas. There is a proposal for a method for recovering the catalytic activity in that manner (see Patent Literature 1).    Patent Literature 1: Unexamined Japanese Patent Publication No. 8-144748

Exhaust gas purifying catalyst, method for recovering exhaust gas purifying catalyst, and catalyst system for exhaust gas purification


A new and distinct Coreopsis plant named ‘Firefly’ characterized by daisy-type inflorescences that grow to 4 cm in diameter, inflorescences that are bright yellow with dark red eyes, hardy to Zone 6 (maybe lower), grass green foliage on short stems, flowering for the whole summer, a very compact, mounding habit, and excellent vigor.

The present invention relates to a new and distinct Coreopsis and given the cultivar name 'Firefly'. Coreopsis is in the family Asteraceae. This new cultivar originated from a controlled breeding program to produce hardy compact Coreopsis. The new cultivar originated from planned cross of two proprietary unnamed Coreopsis verticillata hybrid seedlings. The new cultivar of Coreopsis is an herbaceous perennial to be grown for landscape and container use in a sunny site.
Compared to the parent seedlings the new variety is much shorter with larger flowers and a more upright habit.
Compared to Coreopsis 'Bengal Tiger', U.S. Plant Pat. No. 23,345, the new cultivar is much more compact, with smaller flowers that have darker yellow color and a smaller more concentrated red center.


A worm is a malicious process that autonomously spreads itself from one host to another. To infect a host, a worm must somehow copy itself to the host. The method in which a worm transmits a copy of itself produces network traffic patterns that can be generalized as a traffic behavior. As a worm spreads itself across the network, the propagation of the traffic behavior can be witnessed as hosts are infected, one after another. By monitoring the network traffic for propagations of traffic behaviors, a presence of a worm can be detected.

1. Field of the Invention
The present invention relates to detecting computer worms in a computer network.
2. Background Art
A computer in a network is vulnerable to malicious activities in the network. One such threat is the computer worm. A worm is a process that spreads from one host to another across the network by stealthily copying and running itself on unsuspecting hosts. As the worm spreads and infects more and more hosts, the rate at which the worm can infect other hosts in the aggregate grows at an increasing, often exponential, rate.
A worm runs a copy of itself on an unsuspecting host by exploiting some vulnerability on the host. Since a worm is a computer process, it has the potential to execute malicious code on the host. For example, a worm may delete files or use the processing power of the host to make denial of service attacks on another host. Furthermore, as a worm copies itself to more and more hosts, the network traffic generated by the worm may cause major network congestion. The activities of a worm may impair a host and the network.
Since it is difficult to identify all the vulnerabilities of a host and to predict the new methods in which worms will exploit those vulnerabilities, automatic detection of new worms is particularly challenging.
Today, new worms are detected manually, often after the affects and damage of the new worm are well felt. Once a new worm is discovered, a particular characteristic of the worm is identified and this characteristic is used to detect the future presence of the known worm in the network. Hence, contemporary systems are generally limited to detecting worms that are known a priori.
What is needed is a method and system of detecting new worms automatically so that they may be detected and contained quickly before the worm spreads too far. Automatic detection and response is becoming an imperative because a newly released worm can infect millions of hosts in a matter of seconds.

Method, apparatus, and computer program product for detecting computer worms in a network


A process for preparing a water-absorbent resin made from an α,β-unsaturated carboxylic acid as an essential monomer characterized in that the process comprises allowing a metal chelating agent to be present at any step in the process in an amount of 0.001 to 6 parts by weight, based on 100 parts by weight of the α,β-unsaturated carboxylic acid; and adding a reducing agent or an oxidizing agent thereto in an amount of 0.001 to 6 parts by weight, based on 100 parts by weight of the α,β-unsaturated carboxylic acid before initiation of drying and/or during drying of a gelated product containing a water-absorbent resin obtained by polymerization.

Water-absorbent resins have been widely used as absorbent articles for hygienic materials such as paper diapers and sanitary napkins, utilizing the feature that a water-based liquid, for instance, a body fluid such as human urine, blood or sweat is quickly absorbed in a large amount, so that the liquid once absorbed is not released even under a load.
Conventional water-absorbent resins have some problems that the water-absorbent resins discolor into yellow even immediately after the preparation depending upon the preparation processes, or that the resins are likely to discolor into yellow, brown or the like by an external factor such as heat or humidity when the resins are allowed to stand even if the resins are white immediately after the preparation. In the field of the above-mentioned hygienic materials such as paper diapers, when a water-absorbent resin discolors in the absorbent article, the commercial value as an absorbent article is drastically lowered. Therefore, under severe high-temperature, high-humidity environment such as storehouse in the summer time, it has been desired that a water-absorbent resin does not discolor when the water-absorbent resin or absorbent article is subjected to storage for a long period of time.
As water-absorbent resins having an effect of preventing discoloration, there have been known, for instance, a high water-absorbent polymer composition in which an organic phosphoric acid compound or a salt thereof is added to a high water-absorbent polymer (Japanese Patent Laid-Open No. Hei 5-86251); an absorbent composition comprising an acidic water-swellable crosslinked polymer, a basic water-swellable crosslinked polymer, a discoloration preventive and/or an antioxidant and/or a boron-containing compound (Japanese Patent Laid-Open No. 2000-230129); an absorbent composition comprising a water-absorbent resin, and an organic carboxylic acid and/or a salt thereof (Japanese Patent Laid-Open No. 2000-327926) and the like. However, the above compositions do not exhibit a sufficiently satisfactory effect of preventing discoloration when subjected to high-temperature, high-humidity storage for a long period of time.
Accordingly, an object of the present invention is to provide a water-absorbent resin having no discoloration immediately after the preparation, and having suppressed discoloration even when subjected to a room temperature storage or even to a high-temperature, high-humidity storage for a long period of time.
These and other objects of the present invention will be apparent from the following description.

Process for producing water-absorbing resin


A low form-factor transceiver system appropriate for long-reach optical communications is presented. In accordance with the present invention, an electronic interface to a receiver optical sub assembly (ROSA) and a transmitter optical sub assembly (TOSA) is arranged on a multi-layer board to electrically shield the transmitter and receiver portions from a high-voltage power supply, which is utilized to provide bias voltages to optical detectors in the ROSA. In some embodiments of the invention, the high-voltage power supply is arranged on a top layer while the transmitter and receiver are arranged on a bottom layer in a split-ground arrangement. Layers between the top layer and the bottom layer include at least one ground plane and provide vias for electrical connections.

1. Field of the Invention
The present invention relates to optical communication systems and, particularly to an electronic interface for small form factor high-speed optical transceivers with high sensitivity optical receivers.
2. Discussion of Related Art
There is currently a demand for high-speed, long-distance, cost-effective, and highly integrated optical transceiver systems. Therefore, optical receiver systems that are high performance, low cost, and are of small size are desired. A transceiver typically includes both a transmitter system and a receiver system. A fiber optical transceiver, therefore, can include a receiver optical sub assembly (ROSA), a transmitter optical sub assembly (TOSA), and an electronic interface connecting the ROSA and TOSA.
For short reach and medium distance transmission, the ROSA may include a PIN photo detector based receiver for detecting light from an optical fiber. For long reach transceivers (e.g., for transmission over tens of kilometers), however, high sensitivity receivers are required to compensate for the optical signal loss due to long optical fibers. In long distance systems, then, an avalanche photodiode (APD) can be utilized instead of a PIN photodiode because of its higher sensitivity and lower noise characteristics.
The TOSA can include a laser diode and optics for coupling optical signals generated by the laser diode into a fiber. The electronic interface to the TOSA and ROSA, then, includes drivers for the TOSA, receivers for the ROSA, and power supplies to power the laser diodes and the receiver chips of the ROSA and TOSA. In conventional systems, the electronic circuitry of the power supplies, the transmission circuitry, and the receiver circuitry are well separated in order to minimize the amount of noise generated on the received signals and on the transmitted signals due to the electronics. However, such an arrangement can require a great deal of space for the transceiver system.
Therefore, there is a need for optical transceiver systems, and in particular for long reach optical transceiver systems that have a small form factor and that are arranged to minimize interference and noise on the received signals.

Electronic interface for long reach optical transceiver


Apparatus (10, 30, 60) and a method for generating low energy electrons (26, 46) for neutralizing charges (16, 36, 66) accumulated on a wafer (14, 34, 64) is provided. The apparatus includes a photocathode (24, 44, 67) located within a predetermined distance from the wafer (14, 34, 64), and a light source (20, 40, 70, 76, 86) operable to emit a light (22, 42, 72, 78, 88) striking the photocathode (24, 44, 67), the photocathode (24, 44, 67) generating a cloud of low energy electrons (26, 46) with a narrow energy distribution near the wafer (14, 34, 64).

During certain semiconductor processing steps, the wafer can become adversely charged as to threaten the integrity of the semiconductor devices being fabricated thereon. For example, in the ion implantation process, a beam of positive impurity ions is accelerated and directed onto the surfaces of semiconductor wafers. The wafers are typically positioned on a spinning wheel so that the wafers are periodically implanted and simultaneously charged by the high energy positive ions. Although the wheel is grounded, it is insufficient to remove all or a substantial portion of the positive charges accumulated on the wafers.
In order to neutralize the charging effect, a number of known apparatus and methods have been developed. One is the electron shower where primary electrons are thermionically emitted from a filament. The primary electrons strike a target which emits secondary electrons toward the wafers. In another known method using thermionic emissions from a filament, the primary electrons strike a target which emits secondary electrons through a gas to create a weak plasma. The weak plasma is the source of electrons that may be drawn toward the wafers to counteract positive charging.
In both electron shower schemes, the high energy primary electrons tend to reach the wafers in excess of the number needed to neutralize the positive charge, thus overcharging the wafers negatively. The primary electrons also tend to charge the surface of the target which causes the secondary electrons emitted therefrom to be charged at the same energy as the charged target. The presence of primary electrons also induces a space charge effect in the path of the electrons which tends to divert the primary electrons from the target. Efforts to filter the primary electrons are complicated and difficult to implement due to the unpredictable nature of the charging effects of the wafers. Therefore, a primary electron filtering scheme must be tailored to each individual ion implantation equipment and process. Further, the filament electron source is fragile and prone to breakage if not handled or operated properly.
A third known method for neutralizing the charged wafers is a plasma flood system which creates a plasma that is contained electrically and magnetically near the wafer. The electrons in the plasma are pulled to the wafer to counteract the positive charges thereon. One problem with the plasma flood system is the complex and sensitive nature of the plasma containment system which is difficult to control to achieve good results. Further, the filament used to generate the electrons in a plasma flood system often experiences reduced operating life due to the introduction of a variety of insulators in the containment system that tend to coat the filament.

Apparatus and method for generating low energy electrons


A method for the preparation of a compound of general Formula:

Naturally occurring molecules which exhibit potentially beneficial pharmacological properties are isolable from a range of environments, such as marine, plant and microbial sources. One example of such molecules is the general class of compounds known as the Lamellarins. These polyaromatic alkaloids are isolated from marine sources and comprise a fused polyaromatic framework. Lamellarins C and D have been shown to cause inhibition of cell division in a fertilised sea urchin assay, whereas Lamellarins I, K and L all exhibit comparable and significant cytotoxicity against P388 and A549 cell lines in culture. Recently, Lamellarin N has been shown to exhibit activity in lung cancer cell lines by acting as a Type IV microtubule poison. Furthermore, these compounds have also been shown to possess cytotoxic activity on multidrug resistant cells as well as efficacy as non-toxic modulators of the multidrug resistant phenotype and, therefore, afford an attractive potential source of chemotherapeutic agents.
However, the potential clinical usefulness of the Lamellarins is severely limited by the modest quantities produced naturally as well as the difficulties involved in their isolation. Steglich & coworkers, in Angew. Chem. Int. Ed. Eng. 1997, 36, 155, have described a biomimetic sequence for the synthesis of Lamellarin G trimethyl ether, however, the process is limited in that it lacks regiochemical control and does not readily lend itself to the specific substitution patterns dictated by the natural products. There is a need, therefore, for a synthetic process which enables the production of the Lamellarins and analogues thereof.

Preparation of fused polycyclic alkaloids by ring closure of azomethine ylides, novel compounds thereof and their use as chemotherapeutic agents

Abstract: or pharmaceutically acceptable derivatives and salts, racemates, isomers and/or tautomers thereof comprising cyclizing an azomethine ylide of general Formula:

Abstract: wherein,

Abstract: A is a cyclic or non-cyclic group; Z is a carbon or a heteroatom; n is selected from 0, 1, 2 or 3; W, X and Y may be the same or different and each are selected from hydrogen; optionally substituted alkyl, alkenyl, alkynyl, amino, alkoxy, alkenoxy, alkynoxy, aryl, alkylthio, heterocyclyl; carboxy, carboxy ester, carboxamido, acyl, acyloxy, mercapto, halogen, nitro, sulfate, phosphate, cyano and optionally protected hydroxy; or W and X, together with the nitrogen and carbon atoms to which they are attached, form a saturated or unsaturated nitrogen containing heterocyclic group which may be optionally substituted or optionally fused to a saturated or unsaturated carbocyclic group, aryl group or heterocyclic group is provided.


Methods and systems for enabling transfer of digital content of a webpage to a user device for subsequent consumption by the user device are described. A client computing system receives user input indicating selection of a graphical user interface (GUI) element while presenting a webpage in a browser of the client computing system. The client computing system sends an unauthenticated request to transfer the digital content of the webpage presented in the browser and prompts a user of the browser to login to an account in response to the unauthenticated request. The client computing system sends an authentication request with login information to authenticate the user to automatically authorize operations to transfer the digital content. The client computing system sends an authenticated transfer request to a server computing system to transfer the digital content presented in the browser to the user device for the subsequent consumption by the user device.

A large and growing population of users is enjoying entertainment through the consumption of digital media items, such as music, movies, images, electronic books, and so on. The users employ various electronic devices to consume such media items. Among these electronic devices (referred to herein as user device) are electronic book readers, cellular telephones, personal digital assistants (PDAs), portable media players, tablet computers, netbooks, laptops, and the like. These electronic devices wirelessly communicate with a communications infrastructure to enable the consumption of the digital media items.
It is not uncommon for a user while visiting website on the Internet comes across web documents (e.g., webpages, pdf documents, articles, text documents, word processing documents, blog entries, etc.) that the user wants to send to another computing device, such as the electronic devices described above for subsequent viewing on the other device. The user may wish to read or view the web document on the other device because the user may prefer to view or read the web document on a portable device, or a device that is dedicated to long form reading, such as an electronic book reader. This may provide convenience and portability to the user for reading web documents on other devices. For example, a user may find an article on the web while at work, and may want to read the article on a different device, such as an electronic book reader, at home or while in transit.
Currently, in order to achieve transfers of web documents to these electronic devices, a user performs various manual, tedious steps. For example, to send a webpage to an electronic book reader, the user saves the webpage to disk of the computer on which the user is viewing the webpage (i.e., computer running a web browser). The user then has to convert the saved file into a native format of the user device and deliver the converted file to the user device, such as using a Universal Serial Bus (USB) storage drive, a USB cable, or the like.


A muscular tissue revascularizing apparatus. First electrodes generate a heat effect into the muscular tissue. Second electrodes generate pulsed spark discharge shockwaves into the muscular tissue.

The invention concerns a device for revascularizing muscular tissue by producing a tubular necrosis.
Such devices are known and are finding increasing clinical application, in particular in the field of cardiac surgery.
In the category of xe2x80x9ctransmyocardial laser revascularizationxe2x80x9d, such as laser myocardial revascularization (LMR), predominantly three different laser systems, i.e., pulsed CO2 laser, pulsed holmium-YAG laser, and pulsed excimer laser are currently used, primarily devices from the US companies PLC, CARDIO GENESIS, and United States Surgical Corporation. With these pulsed laser. systems, it is possible, through the use of the mechanism of so-called photoablation, to create transmyocardial channels; and, based on the system, thermally affected marginal zones and also shock waves are produced through the process of photoablation. These systems are extremely expensive, and, even so, amplitude and depth of effect of the shock waves cannot be optimized.
The object of the invention is, consequently, to provide a comparatively simple and economical device for revascularizing muscular tissue, in particular heart muscular tissues, which offers improved possibilities for optimization of the treatment parameters.
The invention includes the technical teaching of providing a device with which, independently of one another, the wall of a tubular necrosis or of the channel generated in the course of revascularization can be deliberately affected thermally and with which shock wave-like pressure amplitudes with separately adjustable parameters can at the same time be generated in the vicinity of the wall.
It also includes the idea of using different energy sources to produce the thermal effects on the one hand and the shock wave effects on the other, in the interest of separate control of the parameters. According to investigations by the inventor, the combined use of HF energy and electrical pulses with relatively high field intensities of an electrical shock wave generator is particularly economical and presents advantageous effects. The HF energy is expediently in the range of a few watts and the pulse field intensity is a few kV/cm.
Surprisingly, it turned out that the use of bifilar, helically wound high frequency electrodes, which are mounted mutually isolated on an puncture needle, causes shrinkage of this tissue upon input of the high frequency energies and distribution in the parietal tissue. After removal of the puncture needle, an open channel remains. At the same time, by deliberate variation of the high frequency energy, the heat introduced into the channel wall can be deliberately varied with a view to the expansion and consistency of the remaining tissue. Similar effects were also obtained with other HF electrode configurations.
By the additional installation of two mutually isolated high-voltage electrodes, which can lie exposed on the end or along the HF application system (the HF puncture needle), it is also possible to produce a spark-like puncture by the brief application of zero-potential high voltage, which in turn produces shock waves in the vicinity.
By variation of the high voltage in the duration of the high-voltage pulse, it is possiblexe2x80x94independently of the introduction of thermally active HF energy via the bipolar HF electrodesxe2x80x94to separately vary the strength of the shock wave amplitudes. Through selection of different bipolar electrode configurations, it is possible to control the thermal coagulation zone.
In a preferred exemplary embodiment, the HF puncture needle is made of a break-resistant ceramic metal composite capillary, on whose outside wall the bipolar HF electrodes are installed and in whose interior the leads of the HP electrodes are guided mutually isolated and attached on the edges of the distal end. However, other suitable materials, such as high temperature resistant plastics (PBEK, PPSU, etc.), may also be used as electrode carriers.
According to a preferred exemplary embodiment, the HF puncture needle is exchangeably mounted in an electrically, mechanically, or hydraulically driven advancing device located in the interior of a hand piece. The hand piece itself is advantageously designed with a distal attachment holder such that during use of the device for perforation of the heart muscle, anchoring in the epicardium is possible and the puncture needle can be inserted under control into the heart muscle by means of the advancing device.
Energy is supplied to the HF electrodes by a bipolar high frequency generator with adjustable output and appropriately adapted terminating impedance; the high-voltage pulse electrodes are supplied by a high-voltage pulse generator.
In further development of the idea according to the invention, to produce larger channel diameters, a rotating hollow knife by which the contour of the channel is cut into the tissue can be provided instead of the puncture needle. The addition of a suction pump on the above-described hand piece makes it possible to aspirate the excess tissue in the interior of the hollow knife.

Device for revascularizing muscular tissues

Laser-und Medizin-Technologies GmbH Berlin