The invention provides a photothermographic material containing a tabular photosensitive silver halide having an average silver iodide content of 40 mol % or higher, 50% or more of a total projected area of the photosensitive silver halide being occupied by tabular grains having an aspect ratio of 2 or more, the photosensitive silver halide grains having a mean equivalent spherical diameter of from 0.2 μm to 5 μm and a variation coefficient of an equivalent spherical diameter distribution of 30% or less. Further, a method for preparing the photosensitive silver halide used in the photothermographic material is characterized in that grains are formed in the presence of at least one selected from a silver halide solvent and an amino group-modified gelatin. A high-sensitivity photothermographic material exhibiting a low fog and a high optical density is provided.

1. Field of the Invention
The present invention relates to a photographic silver halide emulsion, to a silver halide photosensitive material, and to a photothermographic material. More particularly, the invention relates to an ultrathin tabular photographic silver halide emulsion having an average silver iodide content of 40 mol % or higher, to a silver halide photosensitive material, and to a photothermographic material.
2. Description of the Related Art
(Tabular Silver Iodide Grain)
Photosensitive silver halide emulsions for use in photographic technologies generally contain silver chloride, silver bromide, or a silver salt comprising a combination of chloride ion and bromide ion, to each of which a small amount of iodide is added.
Photosensitive silver iodide emulsions are rarely used in photographic technologies, but they are known in this technical field. Silver halide emulsions using grains containing silver iodide of different phases have been reported. Phosphoric acid silver iodide photographic emulsion resulting from coprecipitation of silver with iodide and phosphate has also been reported. However, there have been no reports on different silver iodide phases.
The crystal structure of silver iodide has been studied by crystallographers, especially those involved in photography. It is widely known that silver iodide can exist in three different crystal forms. A silver halide crystal in the most stable form is hexagonal wurtzite-type silver iodide, and is called β phase silver iodide. In addition, silver iodide in a face-centered cubic form, called γ phase silver iodide, is also stable at room temperature. Silver iodide in a body-centered cubic structure, which is stable only at temperatures of about 147° C. or higher and is called α phase silver iodide, also exists.
Regarding the shape of silver iodide grains, many shapes have been reported and tabular silver iodide crystals have been observed. With regard to the method for preparing tabular silver iodine crystals, a preparation method using an excess amount of iodine ions which yields a hexagonal crystal structure composed mainly of β phase silver iodide has been reported.
Concerning tabular silver iodide having a high aspect ratio, a method for preparing tabular silver iodide having a face-centered crystal structure, a thickness of less than 0.3 μm, and an average aspect ratio of 8 or more has been reported as disclosed in Japanese Patent Application Laid-Open (JP-A) Nos. 59-119344 and 59-119350. As a particularly desirable method, disclosed is a method in which the pAg is kept in a range from 1.0 to 2.0 during precipitation of silver iodide and the temperature in the reaction vessel is kept in a range of from 30° C. to 50° C.
A photosensitive silver halide is required to have grains in a uniform average grain size and uniform shape. To realize stable photographic properties and express the photographic characteristic of gradation as required according to applications, grains with these uniform distributions have generally been prepared and, when necessary, mixed or layered.
(Photothermographic Material)
In recent years, in the medical field and the graphic arts field, there has been a strong desire for a dry photographic process from the viewpoints of environmental conservation and economy of space. Further, the development of digitization in these fields has resulted in the rapid development of systems in which image information is captured and stored in a computer, and then when necessary processed and outputed by communicating it to a desired location where the image information is outputed onto a photosensitive material using a laser image setter or a laser imager, and developed to form an image at the location on the photosensitive material. It is necessary for the photosensitive material to be able to record an image with high-intensity laser exposure and that a clear black-tone image with a high resolution and sharpness can be formed.
While various kinds of hard copy systems using a pigment or a dye, such as ink-jet printers or electrophotographic systems, have been distributed as general image forming systems using such digital imaging recording material, images in the digital imaging recording material obtained by such a general image forming system are insufficient in terms of image quality (sharpness, granularity, gradation, tone) needed for medical images used in making diagnoses and high recording speed (sensitivity). These kinds of digital imaging recording materials have not reached a level at which they can replace medical silver halide film processed with conventional wet development.
A thermographic system using an organic silver salt has already been known. This system has an image forming layer including a reducible silver salt (for example, an organic silver salt), a photosensitive silver halide, and if necessary, a toner for controlling the color tone of silver, dispersed in a binder.
A photothermographic material forms a black silver image by being heated to a high temperature (for example, 80° C. or higher) after imagewise exposure to cause an oxidation-reduction reaction between a silver halide or a reducible silver salt (functioning as an oxidizing agent) and a reducing agent. The oxidation-reduction reaction is accelerated by the catalytic action of a latent image on the silver halide generated by exposure. As a result, a black silver image is formed on the exposed region. There is much literature in which photothermographic materials are described, and the Fuji Medical Dry Imager FM-DP L is an example in practice of a medical image forming system using a photothermographic material that has been marketed.
Since this kind of image forming system utilizing an organic silver salt has no fixing step, undeveloped silver halide remains inside the film after thermal development. Thus, there have intrinsically been two serious problems in the system.
One problem is that of instability in preserving an image after a thermal developing process, particularly fogging due to print-out when the material is exposed to light. As a way to improve the print-out, a method making use of silver iodide is known. However, the sensitivity of silver iodide grains known until now is extremely low, and silver iodide grains do not achieve a level of sensitivity that can be used in an actual system. And when a measure for preventing recombination between photoelectrons and positive holes is effected to improve the sensitivity, there is an inherent problem that the characteristic of having good print-out resistance will be lost.
As a way of increasing the sensitivity of a silver iodide photographic emulsion, academic literature discloses, for example, using a halogen acceptor such as sodium nitrite, pyrogallol, or hydroquinone, or immersion in an aqueous silver nitrate solution, or sulfur sensitization at a pAg of 7.5, and the like. However, the sensitization effect of these halogen acceptors is very small and extremely insufficient for use in photothermographic materials of the invention.
Another problem is that light scattering due to the remaining silver halide grains may cause cloudiness whereby the film turns translucent or opaque and image quality is degraded. To solve this problem, ways in which the grain size of photosensitive silver halide grains is made fine (to within a range of practical use of 0.08 μm to 0.15 μm) and the addition amount is reduced as much as possible to suppress the cloudiness caused by the silver halide have been practically employed. However, the compromise results in decreasing the sensitivity further, the problem of cloudiness is neither completely solved, and a dark milky color continues to remain and generate haze in the film.
In the case of a conventional wet developing process, the remaining silver halide is removed by processing with a fixing solution containing a silver halide solvent after the developing process. For the silver halide solvent, many kinds of inorganic and organic compounds are known which can form complexes with silver ions.
Even in the case of a dry thermal developing process, many attempts to introduce similar fixing measures in the material have been made. For example, a method has been proposed where a compound capable of forming complexes with silver ions is incorporated in the film and the silver halide is solubilized (usually referred to as fixing) through thermal development. However, this proposal only applies to silver bromide and silver chlorobromide, and the process also requires an additional heat treatment step for fixing, and the heating conditions require a high temperature within a range of 155° C. to 160° C. Thus, the system is one in which fixing is difficult to achieve.
In another proposal, a separate sheet (referred to as a fixing sheet) that includes a compound able to form complexes with silver ions is prepared, and after thermally developing the photothermographic material to form an image, the fixing sheet is overlaid on the developed photothermographic material, heating is carried out and the remaining silver halide is dissolved and removed. However, since this proposal requires two sheets, from a practical viewpoint the obstacles are that the processing step is complicated and the operational stability of the process is hard to maintain, and that there is a necessity to discard the fixing sheets after processing, resulting in generation of waste.
As another fixing method usable in thermal development, a method is proposed where a fixing agent for the silver halide is encapsulated in microcapsules, and thermal development releases the fixing agent and causes it to act. However, it is difficult to achieve a design that effectively releases the fixing agent. A method for fixing using a fixing solution after thermal development is also proposed, but it requires a wet process and therefore is not adequate for a completely dry process.
As described above, known methods for improving the turbidity of film have negative effects, and there have been substantial difficulties in their practical application.
Attempts have also been made at applying the above-mentioned photothermographic material as photosensitive material for photographing. The "photosensitive material for photographing" as used herein means a photosensitive material on which images are recorded by a one-shot exposure through a lense, rather than by writing the image information by a scanning exposure with a laser beam or the like. Conventionally, photosensitive materials for photographing are generally known in the field of wet developing photosensitive materials, and include films for medical use such as direct or indirect radiography films and mammography films, various kinds of photomechanical films used in printing, industrial recording films, films for photographing with general-purpose cameras, and the like.
For example, an X-ray photothermographic material coated on both sides containing tabular silver iodobromide grains using a blue fluorescent intensifying screen is described in JP-A No. 59-142539. As another example, a photosensitive material for medical use containing tabular grains that have a high content of silver chloride and have (100) major faces, and that are coated on both sides of a support, is described in JP-A No. 10-282606. Double-sided coated photothermographic materials are also disclosed in other patent documents. However, according to these known examples, although fine particle silver halide grains having a grain size of 0.1 μm or less do not cause further hazing, the sensitivity is very low. These grains are therefore not usable for practical applications in photographing. And conversely, when using silver halide grains having a grain size of 0.3 μm or more, because the remaining silver halide increases the degree of haze and adversely affects the print-out, there is severe deterioration of the image quality, and the grains are not usable for practical applications.
Photosensitive materials containing tabular silver iodide grains serving as the silver halide grains are well known in the wet developing field, but there have been no examples of applications thereof in a photothermographic material. The reasons are that, as mentioned above, the sensitivity is low, there is no effective sensitization method, and the technical barriers are even higher in thermal development.
To be usable for this kind of photosensitive material for photographing, the photothermographic material needs a higher degree of sensitivity as well as an even higher level of image quality with respect, for example, to the degree of haze of the obtained image.

Photothermographic material and method for preparing photosensitive silver halide emulsion


A system for generating a digital subtraction image of at least two input images. The system comprises a registration subsystem (1) for generating a plurality of different registrations of the input images (7, 8), based on different values of a registration parameter (6). The system further comprises a subtraction subsystem (2) for generating a plurality of subtracted images by subtracting the input images in accordance with respective ones of the plurality of registrations. The system further comprises a combining subsystem (3) for combining the plurality of subtracted images into a combined subtracted image (9). The registration parameter (6) represents an assumed depth of an object which is visible in the input images (7, 8). The combining subsystem (3) is arranged for assigning a combined pixel value to a pixel position of the combined subtracted image, based on pixel values of or around corresponding pixel positions in the plurality of subtracted images.

Subtraction images are a good means to visualize interval changes between follow-up images. The technique has been applied, for example, to thorax X-ray images. Some studies show that reporting accuracy and speed increase with the use of subtraction images. For example, a non-rigid 2D image registration method is used prior to subtraction of the current image in order to align corresponding anatomical parts. Ideally, the subtraction image should become medium grey except for the places where interval changes have occurred. The most prevalent reason for image artifacts in subtraction images is a difference in patient pose between both acquisitions. In particular, the patient may be rotated in between image acquisitions. For this reason, a technique has been proposed to compensate for a known patient rotation.
The paper "A novel registration method for interval change detection between two chest X-ray images with different rotation angles", by A. Shimizu et al., in: Acad. Radiol. 2006; 13:503-511, hereinafter: Shimizu, discloses a registration technique in which it is assumed that all the X-ray absorption recorded by an X-ray image has taken place in a coronal plane intersecting the patient. The position of this coronal plane is referred to as the depth of the shadow of interest. With this limitation, a synthetic radiographic image is constructed that compensates the difference in patient pose, and thus eliminates the artifacts which may occur in subtracted images when the anatomic structure is imaged from differing angles. According to Shimizu et al., when the depth of the shadow of interest is known from another clinical examination, such as tomography, a subtraction image is computed by registering the two images, based on the known patient rotation and known depth of the shadow of interest, and the interval change of the shadow is examined on the subtraction image. If the depth is unknown or interval changes are detected at different depths, the depth is continuously varied and a series of the subtraction images are constructed and interpreted. To this end, the clinical user observes a sequence of subtraction images with changing depth parameter.


A radio frequency (RF) receiver for receiving transmissions of different modulations includes cycling between a first mode for receiving transmissions of a first modulation that occurs frequently and a second mode for receiving transmission of a second modulation that occurs infrequently. The example RF receiver is cycled between a first modulation for receiving a frequency shift keyed (FSK) transmission from a tire pressure monitoring (TPM) system and a second modulation for receiving an amplitude shift keyed (ASK) transmission from a remote keyless entry (RKE) system. The RF receiver cycles between different modulations to detect the most frequent FSK modulated transmissions while also detecting and receiving the relatively infrequent ASK modulated RKE transmissions without an undesirable delay.

This invention generally relates to a method and system for receiving multiple signals with a single receiver. More particularly, this invention relates to a method of operating a radio frequency (RF) receiver for an automobile to receive signals from multiple systems and modulations.
Increasing numbers of systems installed within an automobile utilize radio frequency communication protocols. For example, nearly all vehicles include a remote entry system that sends a signal that is received by an RF receiver within the vehicle to actuate door and trunk locks. Additionally, the same vehicle may include a tire pressure monitoring system including a sensor in each tire that transmits a signal indicative of current tire conditions.
In addition to the multiple signals from multiple sources, each of the signals is typically transmitted in different modulations that are selected according to characteristics of origins and characteristics of the data transmitted. Accordingly, the RF receiver is programmed to receive different signal modulations. Some signals have priority over other signals in specific circumstances. For example, when an automobile is parked, a remote keyless entry signal may be of increased priority as compared to a signal representing conditions within a tire. Although during operation of the vehicle, the signals from the tire pressure monitoring system would be of increased importance.
Another concern is to ensure that the signal with the current highest priority is received according to desired criteria to provide the desired performance. In some instances, merely cycling the RF receiver to look for each different modulation of signal in turn can result in missing a priority signal for an undesirable length of time. As appreciated such operation can result in unfavorable operation.
Accordingly, there is a need for an RF receiver and method of operating an RF receiver that provides for the receipt of multiple signals of different modulations that receives all signals to prevent delay of any operation for each vehicle system.

Radio frequency (RF) receiver with amplitude-shifted keying/frequency-shifted keying (ASK/FSK) duty cycle optimization algorithm


A dry etching method includes loading a wafer on a lower electrode having at least two cooling paths. Cooling fluids having different temperatures are supplied to each of the cooling paths of the lower electrode so that the multiple cooling paths are at different temperatures from one another. The wafer is etched during cooling.

(a) Field of the Invention
The present invention relates to a dry etching method and an apparatus for performing dry etching, and more particularly to the dry etching method and apparatus including multiple cooling paths.
(b) Discussion of the Related Art
Equipment for manufacturing semiconductor devices is generally classified as either equipment for preceding processes or equipment for subsequent processes. The equipment for preceding processes is used to form a photoresist pattern on a semiconductor substrate, such as coating a photoresist layer, exposing, and developing. In contrast, the equipment for subsequent processes is used for various processes related to a patterned substrate, such as an ion implantation process wherein impurity ions are implanted into the patterned substrate, an etching process wherein a target layer is selectively removed by using the photoresist pattern, a deposit process wherein a thin film is deposited on the semiconductor substrate, and a metallization process wherein a circuit pattern is interconnected.
Etching is generally performed by either a wet etching apparatus or a dry etching apparatus. The known dry etching apparatus includes a lower electrode disposed opposite an upper electrode in an etching chamber. In the known dry etching apparatus, a wafer is loaded on the lower electrode, and process gases are supplied and converted into plasma by the upper electrode.
FIG. 1 shows an example of a lower electrode in the known dry etching apparatus. As shown in the figure, the lower electrode 102 defines cooling paths 104 in which cooling gas flows. A clamping part 106 presses a wafer W loaded on the lower electrode 102, such that the wafer W is held on the lower electrode 102, and is cooled by the cooling gas flowing in the cooing paths 104 during etching of the wafer W.
When the known dry etching apparatus is used to etch the wafer W, the uniformity in the thickness of the remaining layer after the etching process depends on process conditions, such as a source power of the dry etching apparatus, chamber pressure, ratio of process gases, and uniformity of an etch target layer. The uniformity in thickness of the remaining layer is also largely dependent on a rear surface temperature of the wafer.
FIG. 2 is a graph showing etch rate and uniformity in thickness of the remaining layer on the wafer as a function of the rear surface temperature of the wafer. As shown in FIG. 2, both the etch rate and the uniformity in the thickness of the remaining layer are increased as the rear surface temperature of the wafer is increased.
FIG. 3 is a graph showing simulated data of the thickness of the remaining layer as a function of position after etching with the known dry etching apparatus. As shown in FIG. 3, the remaining layer is not uniformly thick.
As described above, in the known dry etching apparatus the temperature of the lower electrode is uniform over the entire rear surface of the wafer. However, uniformity, or lack thereof, of the deposited etch target layer is not accounted for during the setting of process conditions. The uniformity of the deposited etch target layer affects the uniformity in the thickness of the remaining layer. Therefore, it is difficult to improve the uniformity in the thickness of the remaining layer.

Dry etching method and apparatus for performing dry etching


Disclosed is a method for controlling travel of construction heavy equipment with electronic joysticks. The method includes the steps of; inputting a joystick travel function selection signal, first manipulation signals of the joysticks and second manipulation signals of acceleration pedals into a controller; determining whether a joystick travel function is selected or released; when the joystick travel function is selected, performing long-distance travel; and when the joystick travel function is released, performing a work. The working unit such as the boom and the arm and the traveling unit can be selectively driven by using the electronic joystick. Thus, the driver can control the travel of the construction heavy equipment in a comfort sitting posture.

1. Field of the Invention
The present invention generally relates to a method of controlling travel of construction heavy equipment with electronic joysticks, with which a driver can control the travel of the construction heavy equipment in a comfort sitting posture.
The present invention specifically relates to a method of controlling travel of construction heavy equipment with electronic joysticks, capable of selectively driving a working unit and a traveling unit by using the electronic joysticks for the working unit such as a boom, an arm or so forth.
2. Description of the Related Art
In general, construction heavy equipment such as an excavator makes use of an acceleration pedal or a travel lever connected with the acceleration pedal which is for performing travel operation, and a manipulation lever, such as a joystick, for a working unit such as a boom, an arm, a bucket, a swing unit or so forth.
Currently, an electronic joystick is widely used as the manipulation lever, wherein the joystick outputs a signal in proportion to a quantity of manipulation caused by a driver or operator. The signal outputted from the joystick may be an analog voltage signal, a PWM (Pulse Width Modulation) signal, a communication signal, etc.
Various working units including the swing unit and the traveling unit are driven by a hydraulic fluid supplied from a hydraulic pump operated by an engine. A control unit controls a direction and a flow rate of a hydraulic fluid supplied to the working units by controlling various control valves according to the manipulation quantity of the manipulation lever, so that the working units and the traveling unit are driven.
In order to make the heavy equipment travel, the driver has either to press the acceleration pedal with his/her foot or to manipulate the travel lever connected with the acceleration pedal with his/her hand. When the driver manipulates the joystick for the working unit, he/she can work in a state where he/she assumes a comfortable posture on the driver's seat. However, when the travel lever installed a little apart in front of the driver's seat is manipulated, the driver must manipulate the travel lever in a state where he/she leans forward in the driver's seat to a certain degree.
During long-distance traveling, the driver must step on the acceleration pedal under continuous application of a constant force. For this reason, the travel lever is used instead of the acceleration pedal. In this case, the driver must lean forward in the driver's seat for a long time. Thus, the driver easily feels tired.
According to a prior art for overcoming these drawbacks, a manipulation lever for a traveling unit has been installed around a joystick for a working unit. With this configuration, the manipulation lever must be installed separately from a hydraulic line, so that the configuration becomes complicated and production costs are increased.
According to another prior art, a control valve has been installed on a pilot signal line connected to a joystick of a working unit. When the control valve is switched, a pilot signal pressure of the joystick being supplied to the working unit is adapted to be supplied to a traveling unit, so that any one of the working unit and the traveling unit is selectively driven by using the joystick.
However, according to these prior arts, a configuration of a hydraulic circuit becomes complicated, and thereby production costs are increased. Further, there is a limitation that this configuration can not be applied to the state-of-the-art heavy equipment where all the units of the heavy equipment are controlled by electrical and electronic signals from an electronic proportional valve etc.

Method of controlling travel of construction heavy equipment with electronic joysticks

Volvo Construction Equipment Holding Sweden AB


A method and apparatus for rendering a plurality of objects. The method includes receiving ray differential information associated with a ray, determining a first resolution associated with a first surface patch based on at least information associated with the ray and the first surface patch, processing information associated with the first resolution and a database, and determining whether a first geometry representation associated with the first surface patch tessellated at the first resolution is present in the database. The database is associated with a plurality of predetermined resolutions, and the first resolution is equal to one of the plurality of predetermined resolutions. At least one of the plurality of predetermined resolutions includes a first tessellation rate associated with a first dimension and a second tessellation rate associated with a second dimension. The first tessellation rate is different from the second tessellation rate.

The present invention relates in general to computer animation techniques. More particularly, the invention provides a method and system for multiresolution geometry caching based on ray differentials. Merely by way of example, the invention is described as it applies to a ray tracing process, but it should be recognized that the invention has a broader range of applicability.
Throughout the years, movie makers have often tried to tell stories involving make-believe creatures, far away places, and fantastic things. To do so, they have often relied on animation techniques to bring the make-believe to "life." Two of the major paths in animation have traditionally included drawing-based animation techniques and stop motion animation techniques.
Drawing-based animation techniques were refined in the twentieth century, by movie makers such as Walt Disney and used in movies such as "Snow White and the Seven Dwarfs" (1937) and "Fantasia" (1940). This animation technique typically required artists to hand-draw or paint animated images onto transparent media or cels. After painting, each cel would then be captured or recorded onto film as one or more frames in a movie.
Stop motion-based animation techniques typically required the construction of miniature sets, props, and characters. The filmmakers would construct the sets, add props, and position the miniature characters in a pose. After the animator was happy with how everything was arranged, one or more frames of film would be taken of that specific arrangement. Stop motion animation techniques were developed by movie makers such as Willis O'Brien for movies such as "King Kong" (1933). Subsequently, these techniques were refined by animators such as Ray Harryhausen for movies including "Mighty Joe Young" (1948) and "Clash Of The Titans" (1981).
With the wide-spread availability of computers in the later part of the twentieth century, animators began to rely upon computers to assist in the animation process. This included using computers to facilitate drawing-based animation, for example, by painting images, by generating in-between images ("tweening"), and the like. This also included using computers to augment stop motion animation techniques. For example, physical models could be represented by virtual models in computer memory, and manipulated.
One of the pioneering companies in the computer graphics (CG) industry was Pixar. Pixar developed both computing platforms specially designed for CG, and rendering software now known as RenderMan®. RenderMan® was particularly well received in the CG industry and recognized with two Academy Awards®. RenderMan® software is used to convert graphical specifications of objects and convert them into one or more images. This technique is known generally in the industry as rendering.
Pixar pioneered techniques of scanline rendering to render complex scenes. With scanline rendering, geometric complexity is reduced by dividing a scene into separate tiles and by rendering one image tile at a time. As a result, only visible objects within a tile are tessellated. To account for reflection and refraction effects, reflection and refraction maps are used. Using scanline techniques, color bleeding effects of global illumination are simulated by laboriously placing colored light sources in the scene. These lights are sometimes called "bounce lights." The addition of ray tracing techniques to scanline rendering techniques is straightforward as long as the rays intersect geometry in a coherent fashion. Such rays are often called coherent rays. Specular reflection and refraction rays from flat or slightly curved surfaces are usually coherent rays. Furthermore, shadow rays from point lights, spot lights, directional lights, and small area lights are typically also coherent rays. Accordingly, it has been possible to combine ray tracing and scanline rendering.
For general path tracing, there is often much less geometric coherency than for classic ray tracing. This obstacle may be overcome by reordering rays. Unshot rays may be inserted into a pool of rays. For example, the image contribution of each ray is computed before the ray is inserted in the pool, and this weight as well as the ultimate pixel position of the ray color is stored with the pending ray. When sufficiently many rays are waiting to be intersection tested against an object, the geometry is read in, tessellated if not already in tessellated form, and inserted into the cache. This way, scenes can be rendered that are ten times larger than the geometry cache.
One common method to speed up rendering is to simplify geometry that only covers a small part of the image. For example, a coarse geometry representation is used for computing an approximate radiosity solution. Clusters of complex geometry can be substituted by boxes with similar reflective and transmissive properties. During rendering, rays for computing diffuse interreflection are intersected with the original geometry near the ray origins and with the boxes further away. A user-defined distance threshold can be used to switch between the two representations. Additionally, clustered geometry can be used for efficient light transport between distant groups of objects. Instead of computing light transport between all pairs of objects, the far-field radiance of one cluster of objects is computed, the light is transported to the other cluster, and then "pushed down" to its individual surfaces.
Some research has also been performed to speed up direct ray tracing without tessellation. For example, only the high-level description of the objects and a spatial acceleration data structure need to fit in memory. The high-level description may include the control points of NURBS patches or top-level subdivision meshes. These methods appear suitable for ray tracing of complex scenes, at least from a memory usage standpoint.
Additionally, certain conventional ray tracers use parallel ray tracing techniques. For example, many processors can be used on a shared memory computer to obtain interactive frame rates. For good performance, scenes need to fit in the rather small on-chip cache on each processor. In another example, a cluster of PCs is used for interactive ray tracing of complex scenes up to 50 million triangles. Ray coherency ensures that each PC only needs parts of the scene. In simpler scenes, indirect illumination can also be rendered. For example, 20–25 shadow rays per pixel are shot to virtual point lights generated by random walks, and indirect illumination is averaged between neighbor pixels to reduce noise. In yet another example, complex scenes can be handled by dividing the objects between a cluster of PCs. Each surface is tessellated and assigned to a processor. Packets of rays to be tested for intersection are communicated between the processors. After all rays have been shot by a shader, the shader is inserted into a pool of suspended shaders. When all those rays have been traced and shaded, the shader is taken out of the pool and its computation continues.
Moreover, some conventional ray tracers use ray differential techniques. Beam tracing, cone tracing, and pencil tracing trace bundles of light paths instead of infinitely thin rays. General intersection, reflection, and refraction calculations may be difficult since each bounce can split the light beam, light cone, or light pencil. As an improvement, a ray differential method traces single rays, but keeps track of the difference between each ray and two real or imaginary "neighbor" rays. These differences give an indication of the cone or beam size that each ray represents. The curvature at ray-surface intersection points determines how those ray differentials are propagated at specular reflection and refraction. For example, if a ray hits a highly curved, convex surface, the specularly reflected ray may have a large differential, which represents highly diverging neighbor rays. Ray differentials can help in texture antialiasing since they may indicate the best texture filter size, but they often do not help in aliasing of ray hits in terms of visibility: the ray either hits an object or not.
The ray differentials may be generalized for glossy and diffuse reflections. For example, the ray differential corresponds to a fraction of the hemisphere for distribution ray tracing of diffuse reflection. The more rays are traced from the same point, the smaller the fraction becomes. For path tracing of diffuse reflection, the "path differential" is a global value 2d√{square root over (N)}, where d is the ray depth and N is the total number of rays that reach that depth. Distribution ray tracing usually gives smaller, more accurate ray differentials than path tracing.
Conventional ray tracing techniques have limited ability to efficiently compute ray tracing and global illumination in very complex scenes. Hence it is highly desirable to improve techniques for ray tracing.

Flexible and modified multiresolution geometry caching based on ray differentials


A resistance defect assessment device provided on a wafer for assessing a resistance variation defect in a component of an integrated circuit device, the resistance defect assessment device including test patterns capable of measuring a resistance variation component to be the resistance variation defect in each chip area or each shot area of the wafer, wherein the number of test patterns included in one chip area or one shot area is set so that it is possible to estimate the yield of the integrated circuit device.

1. Field of the Invention
The present invention relates to a resistance defect assessment device, a resistance defect assessment method and a method for manufacturing a resistance defect assessment device, and more particularly to a monitoring device for detecting a resistance increase defect in a resistive element or a contact provided in a semiconductor integrated circuit device during the manufacture thereof, a method for assessing a resistance increase defect using such a monitoring device, and a method for manufacturing such a monitoring device.
2. Description of the Background Art
In recent years, the feature size of a semiconductor integrated circuit device has been reduced, and the degree of integration and the processing speed thereof have been increased. Moreover, the size (diameter) of a wafer used for manufacturing the same has been increased.
As the feature size of a semiconductor integrated circuit device is decreased and the degree of integration thereof is increased, the production yield thereof is decreased more significantly by a line-break defect or an inter-line shorting defect in a gate electrode wiring, a metal wiring, an impurity layer to be a source region and a drain region (hereinafter referred to as a "source/drain impurity layer"), a contact connecting a lower wiring layer with an upper wiring layer, or the like. Moreover, due to the increase in the degree of integration and the processing speed thereof, characteristics variations among transistors or resistive elements (e.g., gate electrode wirings, metal wirings or a source/drain impurity layer) provided therein also present a significant cause of a decrease in the production yield. Thus, in order to improve the production yield of a semiconductor integrated circuit device while realizing a high processing speed thereof, it may be necessary to suppress, particularly, the variations among the resistors (resistive elements), including the variations in the transistor characteristics.
Conventionally, complete line-break defects and inter-line shorting defects have been addressed as the primary defects in the gate electrode wiring of a transistor, the metal wiring on a transistor, etc. Moreover, the amount of line-break defect or shorting defect (the number of defects) has been measured in order to estimate the yield of a semiconductor integrated circuit device.
In a conventional method for assessing line-break defects and shorting defects, long wirings whose length is on the order of 10 cm to 1 m are routed to form a comb/serp pattern so as to assess the yield of the object layer (wiring layer) (see, for example, Charles Weber, "Standard Defect Monitor", 1988 IEEE Proceedings on Microelectronic Test Structures, Vol. 1, No. 1, February 1988, pp. 114-119 (hereinafter referred to as "Reference 1")).
FIG. 25 shows an example of a conventional comb/serp line pattern. Referring to FIG. 25, in the yield assessment method of Reference 1, the resistance between the comb pads is measured to detect a line-break defect, and the leak current between a comb pad and the serp pad is measured to detect a shorting defect. Particularly for the line-break defect, a very long line is virtually routed so as to allow for the yield assessment. Therefore, it only detects a complete line-break defect but does not detect a resistance increase (resistance variation) occurring in a portion of (at a certain point along) the line.
In another method proposed in the art for assessing a resistor variation, the dimension of the formed pattern is electrically measured so as to assess the influence of a dimensional variation in the gate electrode wiring, or the like (see, for example, Andrew Grenville, et al., "Electrical Critical Dimension Metrology for 100-nm Linewidths and Below", In Optical Microlithography XIII, Proceedings of SPIE, Vol. 4000, 2000, pp. 452-459 (hereinafter referred to as "Reference 2")). Such a dimensional variation leads to a resistor variation or a transistor characteristics variation, thus decreasing the yield. Therefore, assessment of the influence of a dimensional variation is also important.
A defect may occur even in a case where a gate electrode wiring, a metal wiring, a contact connecting an impurity layer with a wiring layer, or the like, is not completely broken, i.e., where a portion of such a component has an increased resistance (the resistance of the component is higher at a certain position than at other positions) even though the electrical connection thereof is maintained within the component. Such a defect may also cause a decrease in the yield or the reliability. The term "resistance increase defect (resistance variation defect)" or "soft-open defect" as used herein refers to such a defect where a component (a resistive element, a contact, etc.) has a locally-increased resistance (thereby also increasing the overall resistance of the resistive element) even though the component is not completely broken and the electrical connection therein is maintained. The term "line-break defect" or "hard-open defect" as used herein refers to a defect where a resistive element or a contact is completely broken.
Along with the recent reduction in the feature size of a semiconductor integrated circuit device and the increase in the degree of integration and the processing speed thereof, the delay time margin has been decreased, whereby even a resistance increase defect occurring at one position along a resistive element such as a line can cause a decrease in the yield and the reliability.
In the formation of a gate electrode wiring, for example, a silicide layer is typically formed on a polysilicon electrode using a salicide process. Even if the silicide layer on the polysilicon electrode is broken, the overall electrical connection of the gate electrode wiring is maintained by the lower polysilicon electrode. However, a resistance increase defect occurs at the position where the silicide layer is broken, thus causing a decrease in the yield and the reliability.
Similarly, a local resistance increase defect (soft-open defect) may occur at a certain position along a lower metal wiring, or in a contact connecting a source/drain impurity layer of a transistor, or the like, with an upper wiring layer. Thus, a variation (i.e., an increase) in the contact resistance, which is one form of a resistor variation, is a significant cause of a decrease in the yield and the reliability.
Recently, a semiconductor integrated circuit device uses a very large number of contacts therein. For example, in a 0.13 μm-rule chip having an area of about 40 mm2, the number of contacts used for the transistor-wiring layer connection is as large as about 20,000,000. Therefore, in a contact yield assessment using a monitoring device (assessment device), the assessment needs to be done for about 10,000,000 contacts.
Conventionally, the contact yield assessment has been done to detect complete line-break defects (hard-open defects). Specifically, for such a yield assessment, a large contact chain resistor pattern (including about 100,000 contacts) is provided to assess line-break defects (hard-open defects) in the contact chain.
FIG. 26A and FIG. 26B illustrate an example of a conventional contact chain resistor pattern, wherein FIG. 26A is a plan view and FIG. 26B is a cross-sectional view taken along line a-a′ of FIG. 26A.
Referring to FIG. 26A and FIG. 26B, a plurality of lower-layer wirings 3 formed from a polysilicon layer or an amorphous silicon layer are provided on a silicon substrate 1 with an insulating film 2 therebetween. An interlayer insulating film 4 is formed over the insulating film 2 and the lower-layer wirings 3, and a plurality of contact electrodes (contact holes) 5 connected to the lower-layer wirings 3 are formed in the interlayer insulating film 4. Moreover, a plurality of upper-layer metal wirings 6 are formed on the interlayer insulating film 4 so as to be connected to the contact electrodes 5. The lower-layer wirings 3 and the upper-layer metal wirings 6 are connected to each other via the contact electrodes 5 therebetween, thus forming a contact chain resistor pattern as illustrated in FIG. 26A. Note that the silicon substrate 1, the insulating film 2 and the interlayer insulating film 4 are not shown in FIG. 26A for the sake of simplicity. Alternatively, instead of providing the insulating film 2 and the lower-layer wiring 3, a transistor source/drain impurity layer may be formed on the surface of the silicon substrate 1 with contact electrodes being formed so as to connect the source/drain impurity layer with the upper-layer wirings.
The contact chain resistor pattern illustrated in FIG. 26A and FIG. 26B includes about 100,000 contacts. If a contact defect to be assessed is a complete line break (hard-open defect), it can be detected by detecting the contact chain resistance being infinitely high.
However, if only one contact becomes defective with the resistance thereof being increased to 10 times the normal value thereof, for example, the resulting variation in the overall resistance of the entire contact chain resistor pattern will be only about 1/10000 of the resistance increase defect. Therefore, it is difficult with an ordinary measurement method to detect such a resistance increase defect occurring in a single contact in the contact chain.
To address the problem, it has been proposed in the art to measure the resistance of each individual contact by providing a cross-contact array of 256 rows by 16 columns (a total of 4096 contacts) and using an 8-bit binary counter and a 256-bit decoder (see, for example, Takeshi Hamamoto, et al., "Measurement of Contact Resistance Distribution Using a 4k-Contacts Array", IEEE Transactions on Semiconductor Manufacturing, Vol. 9, No. 1, February 1996, pp. 9-14 (hereinafter referred to as "Reference 3")). With this method, it is possible to detect a resistance abnormality of a small resistance variation and thus to assess the yield.
However, the assessment of the resistance increase defects (soft-open defects) as described above is more difficult than the assessment of complete line-break defects (hard-open defects). For example, a line-break defect results in a very high or infinitely high electrical resistance, whereby it is possible to perform the defect assessment and the defect density assessment by virtually routing a very long line as described in Reference 1. However, it is difficult to detect resistance increase defects (soft-open defects) even by performing the defect assessment by virtually routing a very long line. This is because a resistance increase at the position of a soft-open defect will be inconspicuous in the overall resistance of the long line, whereby it is not possible to detect the resistance increase.
The methods described in Reference 2 and Reference 3 are disadvantageous in that they result in a very long process TAT (turn-around time) for providing the contact array, or the like. With these conventional techniques, the process TAT for providing the assessment device will be as long as that for making a semiconductor integrated circuit device, whereby the feedback of the assessment results for improving the process will take a very long time.

Resistance defect assessment device, resistance defect assessment method, and method for manufacturing resistance defect assessment device

Matsushita Electric Industrial Co., Ltd.


An apparatus and method for detecting intrusions in Voice over Internet Protocol systems with distributed stateful intrusion detection. When a Session Initiation Protocol (SIP) signal is received as an application-layer protocol signal, the received application-layer protocol signal is distributed to a first finite-state machine and to a second finite-state machine. A data processing system detects that the application-layer protocol enters a first application-layer protocol state S1 at a first node at a first time, determines whether the application-layer protocol fails to enter a second application-layer protocol state S2 at a second node within δ seconds, a positive real number, and generates a signal that indicates a potential intrusion in response to the determination.

An intrusion is when an unauthorized user (e.g., a "hacker," etc.) attempts to break into or misuse (e.g., steal confidential data, etc.) a computer system. An intrusion-detection system (IDS) monitors messages (e.g., packets, etc.) incoming to a computer system and outgoing from the computer system, and based on these messages tries to determine whether an intrusion is being attempted. An intrusion-detection system might conclude that an intrusion attempt is in progress when an atypical or suspicious sequence of messages occurs, or when a sequence of messages matches a known attack signature.
FIG. 1 depicts a schematic diagram of telecommunications system 100 in accordance with the prior art. As shown in FIG. 1, telecommunications system 100 comprises internal network 101 (e.g., a corporate metropolitan-area network, a residential local-area network, etc.), which receives messages via an external network (e.g., the Internet, etc.) and sends messages via the external network to external data-processing systems.
FIG. 2 depicts a schematic diagram of the elements of internal network 101, in accordance with the prior art. As shown in FIG. 2, internal network 101 comprises: intrusion-detection system (IDS) 220, firewall 215, and computer systems 204-1 through 204-N, where N is a positive integer, interconnected as shown.
Each computer system 204-n, where nε1, 2, . . . , N, might be a personal computer, a server, a laptop computer, a personal digital assistant (PDA) with wireless local-area network communication capability, etc.
An incoming message that is directed to computer system 204-n, where nε1, 2, . . . , N, first passes through firewall 215, which inspects the message and decides whether to block the message from reaching its destination or to let the message through based on rules in a rule set. Examples of rules include: block all messages from domain badguys.com; block all messages except those of a certain protocol type; etc.
If firewall 215 lets the incoming message through, then intrusion-detection system (IDS) 220 subsequently receives the message and inspects it. Intrusion-detection system (IDS) 220 provides an additional layer of security by detecting intrusion attempts that comprise one or more messages that are allowed through firewall 215. For example, firewall 215 might restrict external access to a web server in internal network 101 to port 80, but without an intrusion-detection system, it might be possible to attack the web server itself via legitimate traffic through port 80 due to bugs in the web server software (e.g., ColdFusion, Apache, etc.). As an analogy, firewall 215 acts as a "fence" around internal network 101. A fence provides security but does not have the ability to detect when someone is trying to break in (e.g., by digging an underground tunnel, etc.). Intrusion-detection system (IDS) 220 typically can recognize some break-in attempts that firewall 215 cannot detect, and therefore it is advantageous to deploy intrusion-detection system (IDS) 220 in addition to firewall 215 for added security.
When intrusion-detection system (IDS) 220 relies on an attack signature database, it is essential to keep the database up-to-date. In particular, over time malicious users often discover new techniques to exploit vulnerabilities and attack systems, and in response security experts formulate new attack signatures to guard against these techniques. As in the case of antivirus software, the owner of intrusion-detection system (IDS) 220 typically has two options to ensure that the attack signature database is regularly updated with new attack signatures: either subscribe to an automated update service provided by the vendor of intrusion-detection system (IDS) 220, or manually check for new attack signatures and retrieve and install them. In either case, the efficacy of intrusion-detection system (IDS) 220 depends on the owner's diligence—in the former option, the owner must periodically pay subscription fees in a timely fashion, and in the latter option, the owner must check for new updates with great frequency—as well as some combination of time, effort, and money.
Voice over Internet Protocol (VoIP) systems transmit voice traffic over packet-switched Internet Protocol (IP) data networks in lieu of circuit-switched telephony networks (e.g., the Public Switched Telephone Network, etc.). Typically, Voice over Internet Protocol systems are based one of two main protocols: H323 and Session Initiation Protocol (SIP). In both types of systems, VoIP user agents at the calling and called telecommunications terminals (e.g., hardphones, softphones, etc.) send and receive packets that contain encoded voice signals in accordance with the Real-time Transport Protocol (RTP). In addition, a VoIP gateway might employ a media management protocol such as the Media Gateway Control Protocol (MGCP) or MEGACO/H.248 in order to translate traffic transparently between an IP-based network and a non-IP-based network (e.g., between a PSTN phone and an IP phone, etc.).
A key benefit of VoIP is that it enables the convergence of voice and data networks. By migrating voice traffic to data networks, however, the voice network becomes vulnerable to intrusions and other attacks (e.g., denial-of-service attacks, authentication attacks, etc.) that compromise privacy, quality of service, and accurate billing. Moreover, due to characteristics of Voice over Internet Protocol systems, some intrusion-detection systems of the prior art provide inadequate security against intrusions that employ VoIP packets (i.e., VoIP-based intrusions).

Distributed stateful intrusion detection for voice over IP


Techniques are disclosed relating to wide towing of marine survey signal sources. In one embodiment, an apparatus includes a signal source and a wing coupled to the signal source. In this embodiment, the wing is configured to impart a force to the signal source when towed through a body of water by a survey vessel. In this embodiment, the force includes a lateral component and a vertical component. The wing may be configured to impart the force based on a shape of the wing and an orientation of the wing. The wing may extend over at least a third of a length of a keel of the apparatus. At least a majority of a top surface of the wing may be oriented within 20 degrees of parallel to a surface of the body of water. The wing may include a plurality of wing sections.

Marine geophysical surveys are often used for oil and gas exploration in marine environments. Various types of signal sources and sensors may be used in different types of geophysical surveys. For example, seismic surveys are based on the use of sound waves. In such a survey, a vessel may tow an acoustic source (e.g., an air gun or a marine vibrator) and a plurality of streamers along which a number of sound sensors (e.g., hydrophones or geophones) are located. Sound waves generated by the source may then be transmitted to the earth's crust and then reflected back and captured at the sensors. Sound waves received during a seismic survey may be analyzed to help locate hydrocarbon-bearing geological structures, and thus determine where deposits of oil and natural gas may be located. As another example, electromagnetic (EM) surveys may be conducted using EM signals transmitted by a submerged antenna and detected by EM receivers.
U.S. Patent Application Publication No. 2012/0257474 entitled "Method for Seismic Surveying using Wider Lateral Spacing between Sources to Improve Efficiency," which is incorporated by reference herein, discloses some advantages of wide lateral spacing of towed signal sources.
This specification includes references to "one embodiment" or "an embodiment." The appearances of the phrases "in one embodiment" or "in an embodiment" do not necessarily refer to the same embodiment. Particular features, structures, or characteristics may be combined in any suitable manner consistent with this disclosure.
Various units, circuits, or other components may be described or claimed as "configured to" perform a task or tasks. In such contexts, "configured to" is used to connote structure by indicating that the units/circuits/components include structure that performs the task or tasks during operation. As such, the unit/circuit/component can be said to be configured to perform the task even when the specified unit/circuit/component is not currently operational (e.g., is not on). The units/circuits/components used with the "configured to" language include hardware—for example, circuits, memory storing program instructions executable to implement the operation, etc. Reciting that a unit/circuit/component is "configured to" perform one or more tasks is expressly intended not to invoke 35 U.S.C. §112, sixth paragraph, for that unit/circuit/component.
As used herein, the term "based on" is used to describe one or more factors that affect a determination. This term does not foreclose additional factors that may affect a determination. That is, a determination may be solely based on those factors or based only in part on those factors. Consider the phrase "determine A based on B." This phrase connotes that B is a factor that affects the determination of A, but does not foreclose the determination of A from also being based on C. In other instances, A may be determined based solely on B.

Wing for wide tow of geophysical survey sources


The present invention relates to a method for assembling molecules on the surface of a two-dimensional material formed on a substrate, the method comprises: forming a spacer layer comprising at least one of an electrically insulating compound or a semiconductor compound on the surface of the two-dimensional material, depositing molecules on the spacer layer, annealing the substrate with spacer layer and the molecules at an elevated temperature for an annealing time duration, wherein the temperature and annealing time are such that at least a portion of the molecules are allowed to diffuse through the spacer layer towards the surface of the two-dimensional material to assemble on the surface of the two-dimensional material. The invention also relates to an electronic device.

The possibility to assemble organic molecules on two-dimensional materials (2D materials), such as for example graphene has recently been proposed to provide enhanced electronic properties of 2D materials. The assembly of molecules on 2D materials may also provide means for creating novel 2D materials with properties which are not available in bare 2D crystals.
It appears that the organization and conformation of molecules on the 2D crystal may influence the electronic structure of the 2D material by interplay of interactions between the 2D material and deposited molecules. However, it is of importance that the molecules form a layer on the 2D material and not form closely packed islands.
Traditionally, molecules are deposited onto the 2D material in ultra high vacuum (UHV) conditions. However, the molecule-2D material complex prepared by sublimation of molecules onto the 2D material in UHV conditions—is chemically unstable and deteriorates upon exposure to ambient conditions, and this complicates the use of the molecule-2D material for some implementations, such as implementations employing doped 2D-materials, where the doping may be achieved by assembly of dopant molecules on the surface of the 2D material.
Accordingly, there is room for improvements in processes for preparing composites of 2D material having a molecular layer on the 2D material surface. There also appears to be a need for such composites with improved chemical stability.

Assembling of molecules on a 2D material and an electronic device


For configuring and installing access control devices at an installation site, configuration data for unidentified access control devices of the installation site is stored (S10) in a cloud-based computer system (1). The cloud-based computer system (1) receives (S2) a registration assigning the installation site to a media identifier stored in a setup media device. A particular one of the access control devices (4) at the installation site reads (S40) the media identifier stored in the setup media device (5). The media identifier from the particular access control device (4) is received (S5) in the cloud-based computer system (1). In the cloud-based computer system (1), the particular access control device (4) is mapped to one of the unidentified access control devices of the installation site. The configuration data of the mapped access control device is transmitted (S80) from the cloud-based computer system (1) to the particular access control device (4).

Access control devices that control access to restricted areas closed off by doors are separate units which are connected to the doors on the site where the door is installed. Typically, the access control devices include an electromechanical locking device and an access controller controlling the locking device. The access controller may include a keyboard for entering a passcode and/or a card reader for reading identification and/or authorisation information from a user's card through an RFID (Radio Frequency IDentification), magnetic, or contact-based interface. Unfortunately, different types and sizes of doors or gates have different connection interfaces and require different control signals. Unless, an access control device is pre-configured for a specific type of door or gate, the access control device needs to be configured on-site after it has been installed and connected to the door or gate. While pre-configuration of access control devices would make on-site configuration unnecessary, it requires laborious management of the pre-configured devices (the particular device must be at the right time at the right location with the right configuration and assignable to a specific door or gate) and is inflexible and error-prone. On the other hand, on-site, ad-hoc configuration of individual access control devices is extremely inefficient, particularly in buildings having a lot of restricted areas with different types of doors and gates.
EP 2701124 describes a method of configuring a lock control unit of an access control system. The lock control unit is associated with an electronic key and is configured for wireless communication with a mobile user unit. According to EP 2701124, prior to installing the lock control unit at a particular location, the lock control unit and the particular location are registered in the access control system. The lock control unit sends its lock control unit identifier to the mobile unit. An electronic key is requested from the access control system. The mobile unit communicates with the lock control unit and sends to the lock control unit the electronic key and optionally one or more parameters.
WO 2014/044832 describes a method and a system for the configuration of locking systems with electronic locks that communicate with passive RFID cards. According to WO 2014/044832, the electronic locks and the RFID cards are configured by way of smartphones. An administration app of the smartphone accesses a cloud service for storing centrally in the cloud data of the locking system and requesting key and programming data. The smartphone is then be used to transfer the key data and the programming data to the locking system and the RFID cards.

Method and devices for configuring access control devices at an installation site


Aspects disclosed pertain to providing trust recommendations. The innovation receives fidelity data of an advisor. The fidelity data can include audio or visual data of the advisor in which the advisor is providing advice. A trust score for the advisor is determined based on a biometric or other analysis of the fidelity data. The trust score is compared to a threshold trust score to determine a recommendation to the user. The recommendation can be to trust or distrust the advisor or the advice. The recommendation is communicated or otherwise provided to the user.

Various advisors provide financial advice, whether in person or on television, to a user. The financial advice is relied upon to make important decisions regarding a user's accounts and investments. However, it is challenging to determine the accuracy or trustworthiness of a financial advisor. A natural language processing system may be able to inform the user regarding the trustworthiness of the advisor's assertions.


The efficiency of converting electrical energy into a mechanical output is maximized by alternatively matching selection of power supply for the drive coil applying a magnetic field to transducer element made of a magnetostrictive material having a near-zero magnetic anisotropy, or matching selection of the magnetostrictive material to the required magnetostriction for a given power supply.

The present invention relates in general to magnetostrictive transducer devices through which electrical energy is converted into mechanical energy output.
Magnetostrictive materials are now being used as transducer elements in a variety of installations such as high power underwater sound projectors and high strain active vibration isolators. Electrical energy sources providing a high power supply are usually required for such installations in order to generate relatively large dynamic magnetic fields. Frequently, the capability of the power supply for such installations limits the mechanical output to be produced. Also in order to obtain good efficiency in converting the electrical energy within such installations, the magnetostrictive transducer output under stress and strain is matched to the expected load impedance. It is therefore an important object of the present invention to avoid the mechanical output limitation heretofore experienced in the aforementioned type of energy conversion installations while providing acceptably good conversion efficiency.
In accordance with the present invention, energy conversion efficiency for high power installations involving magnetostrictive transduction is maximized by either matching the magnetostrictive material to the power source or matching the power source to the required strain imposed by loading on magnetostrictive transduction material having a near zero magnetic anisotropy.

Efficiency maximized conversion of electrical to mechanical energy by magnetostrictive transduction

The United States of America as represented by the Secretary of the Navy


A pipe handling apparatus for handling pipe stands and stands of collars. The pipe handling apparatus improves the safety and efficiency of a rotary drilling operation. The pipe handling apparatus is integrated with a derrick monkey board, away from the heavy machinery within the derrick. The pipe handling apparatus is used for handling, storing and replacing pipe stands during the tripping out and tripping in processes.

In an oil or gas drilling operation, the derrick is the support structure for the equipment used to lower and raise the drill string into and out of the wellbore. The drill string is a column of coupled drill pipes and drill collars that transmit torque and drilling fluid to the drill bit. Either a kelly drive or a top drive apparatus provides the torque to rotate the drill string and induce cutting and crushing of subterranean earth digging by the drill bit. Drill collars comprise the section of the drill string nearer the drill bit and are heavy, thick-walled tubes used between traditional drill pipe and the bit in the drill stem. The increased mass of the thicker collars provides increased downward force for the drill bit. As drilling depth increases, drill pipes are inserted between the derrick and the heavier drill collars.
The drill depth may reach many thousands of feet. Although the drill bit is made of hard materials, such as tungsten carbide, and continuously lubricated with drilling fluid, drill bit wear is inevitable. Consequently, the entire drill string must be removed several times during the drilling process to replace worn drill bits. The drill string may also be removed for replacing other equipment, running casing, or other reasons. The drill string removal and replacement process is known as "tripping pipe."
During the pipe tripping process, a portion of the drill string is pulled out of the well bore and up into the derrick. Drill pipes, typically about 30 ft in length, are removed in sections of coupled drill pipes called pipe stands. The number of drill pipes that comprise a pipe stand is governed by the height of the derrick. Pipe stands typically comprise 3 coupled drill pipes, but may comprise 2 or 4 coupled drill pipes. As the drill string is pulled out from the well bore, a pipe stand is threadably uncoupled from the drill string below. An uncoupled pipe stand is suspended by elevators attached to a drill line more than 90 ft. above the drill floor.
A typical five man drilling crew comprises two floorhands and a derrickman, who employ heavy equipment and physical strength to disassemble and reassemble a pipe string and temporarily store pipe stands during the tripping process. The lower portion of a pipe stand rests on one end of the drill floor called the setback area. The upper portion of a pipe stand is racked within the fingers of a racking board. In a concerted effort, the derrickman pulls the top of a suspended drill stand away from the well bore center line while a floorhand pushes the lower portion of the suspended pipe stand to the setback area. The drill line lowers the pipe stand onto the setback area of the pipe rack floor. The derrickman racks the upper portion of the drill stand within the racking board for temporary storage during the tripping process. The process is repeated until all the pipe stands and collars, often comprising a total of thousands of feet in length, have been removed. After replacement of the drill bit or other equipment, this process is reversed to reinsert all the pulled collars and pipe stands into the well bore to continue the drilling process.
The pipe tripping process is extremely dangerous. Rig personnel are working alongside heavy equipment and machinery capable of exerting exceedingly powerful forces. The derrickman works unaccompanied more than 90 ft above the drill floor. The drilling process usually continues for 24 hours a day, despite adverse weather conditions. Drilling mud, a viscous but slippery hydrated polysaccharide suspension, spills out of drill pipes, litters the drill floor and equipment, and obscures safety goggles. Human error, fatigue, extreme weather conditions, and chemical contaminants contribute to the dangers of pipe tripping. The International Association of Drilling Contractors (IADC) recognizes pipe tripping as the operation that involves the most lost-time and recordable injuries. The IADC recognizes drill pipes and collars as the equipment responsible for the most lost time after drilling rig accidents.
The drilling industry has attempted to address the dangers associated with personnel working on the drilling floor by developing mechanical pipe handling equipment.
U.S. Pat. No. 3,633,767 describes a pipe-racking apparatus employing a pantographic transfer arm that telescopes toward the well bore center line to retrieve pipe stands. U.S. Pat. No. 4,013,178 describes a pipe racker with a maneuverable arm that can pivot about an axis but requires an additional cable-lift system for handling drill collars. U.S. Pat. No. 4,044,895 describes a pipe racking apparatus comprising a pivotally mounted chute that positions single drill pipes, but not pipe stands, within a container. U.S. Pat. Nos. 4,117,941 and 4,274,778, and 4,621,974 describe devices for handling and racking drill pipes comprising upper and lower manipulators, requiring significant modification of upper and lower sections of the derrick. U.S. Pat. No. 4,345,864 descries a pipe stand moving apparatus having a gripping head mounted to a cantilever arm, but relies on several moving parts for operation including a worm gear, chains, drive sprockets, and other gears. U.S. Pat. No. 5,183,122 describes a derrick for raising or lowering drill string comprising a derrick frame, a rack, a gantry, and a pipe gripping unit. U.S. Pat. No. 6,343,662 describes a hydraulic drilling rig with a movable pipe support cradle that transfers pipe stands to a storage area. U.S. Pat. No. 6,821,071 describes an automated pipe racking apparatus with a rotatable arm support member that moves the top of a pipe stand and base grids mounted on the drill floor. U.S. Pat. No. 7,731,746 describes a pipe manipulator arm mounted to a rotatable assembly attached to the derrick.
The mechanical pipe handling equipment of the prior art includes integrated mechanisms for movement in forward, rear, up, and down directions and circular or rotational movement. The mechanical integration of the mechanisms responsible for movement in multiple directions requires complicated equipment that is difficult to service. There is a need in the art for a simple, compact, efficient, stable mechanical pipe handling apparatus that obviates the need for a derrickman and can be attached to an existing derrick. There is also a need in the art for a mechanical pipe handling apparatus that separates the mechanisms responsible for forward and rear, up and down, and rotational movement. While the invention has been described with a certain degree of particularity, it is to be noted that many modifications may be made in the details of the invention's construction and the arrangement of its components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification.


A water valve assembly includes a valve body having defined therein (1) a first fluid inlet, (2) a temperature sensing port, (3) a fluid outlet, and (4) a fluid channel in fluid communication with the first fluid inlet, the temperature sensing port, and the fluid outlet. The assembly also includes a first water valve being in fluid communication with the first fluid inlet. The assembly also includes a sensing device having a temperature sensing surface being positioned in thermal communication with the temperature sensing port. In addition, the assembly further includes a pressure inlet member having a pressure channel defined therein. The sensing device further has a pressure sensing surface, and the pressure channel is positioned in fluid communication with the pressure sensing surface. A method of operating a water valve assembly is also disclosed.

The present invention relates generally to a water valve assembly, and more specifically to a water valve assembly having a temperature and pressure sensing device integrated therein.
Solenoid-controlled water valve assemblies are commonly used in many household appliances such as clothes washing machine and dishwashers. Such appliance water valve assemblies typically include a cold water valve and a hot water valve and are generally controlled by a controller included in the appliance thereby providing a flow of water for use by the appliance.
The appliance typically includes a pressure switch. The pressure switch is coupled to a pressure sense line. Air pressure within the pressure sense line varies proportionally as the water level within a wash basin in the appliance changes. More specifically, as the water level within the wash basin increases, air pressure within the pressure sense line also increases, and vice versa. If the air pressure within the pressure sense line exceeds a predetermined limit associated with the switch, the switch actuates thereby causing the controller to generate an output signal which closes the cold water valve and the hot water valve thereby ceasing the flow of water into the wash basin of the appliance.
Moreover, the appliance sometimes includes a temperature sensor. The temperature sensor senses the temperature of the water entering the appliance. If the water temperature varies from a predetermined temperature, the controller generates an output signal which causes either the cold water valve or the hot water valve of the water valve assembly to open thereby providing for a flow of either cold or hot water, respectively, into the wash basin of the appliance.
One drawback associated with appliances which have heretofore been designed is that the water valve assembly, the pressure switch, and the temperature sensor are each separate, discrete devices. Such a configuration is undesirable in that separate, discrete devices generally consume more space and increase the cost associated with the appliance. This is true since each of the devices must be individually installed in the appliance thereby increasing labor cost associated with manufacturing the appliance.
What is needed therefore, is an appliance water valve assembly which has a temperature and pressure sensing device integrated therein. What is further needed is a water valve assembly which reduces the number of separate devices associated with the appliance relative to appliances which have heretofore been designed thereby reducing the cost associated with the appliance.

Water valve assembly having a temperature and pressure sensing device integrated therein


A central differential has first and second output members for distributing power of an engine through a transmission to front and rear wheels respectively, and has a third output member for controlling distribution of the power. A first friction clutch is operatively connected to the first and second output members for restricting differential operation of the central differential and for controlling distribution of the power to the front and rear wheels. A second friction clutch is operatively connected to the second output member and either the front or rear wheels. A brake is provided for braking the second output member for providing a higher speed gear ratio than that of the smallest gear ratio of said transmission and to improve driveability of said vehicle.

The present invention relates to a system for transmitting power of an engine to four wheels of a four-wheel drive motor vehicle having a central differential, and more particularly to a system which may increase the number of the speed ranges of an automatic transmission.
A conventional four-wheel drive motor vehicle has the central differential having a functional control device for restricting the differential operation and for controlling distribution of an output torque of the transmission to front and rear wheels of the vehicle. Recently, the central differential is used for variably controlling the torque distribution, or used as a reduction gear or speed-up gear for the automatic transmission, thereby improving driveability, operability, stability and braking effect of the vehicle.
Japanese Patent Application Laid-Open 4-27622 discloses the four-wheel drive motor vehicle providing the central differential which comprises a complex planetary gear device and a control device is provided. The control device comprises first and second fluid operated multiple-disk friction clutches and a brake for a 5th speed for providing a 5th speed. The first clutch is provided for transmitting the power of an engine from a transmission to front and rear wheels. The second clutch is provided for restricting the differential operation of the central differential and variably distributing the output torque of the transmission to the front and rear wheels.
However, in such a system, the torque distribution function and differential operation function are limited by the 5th speed providing system.
Furthermore, it is desirable for be capable of using such a central differential for a two-wheel drive motor vehicle such as a front-wheel drive motor vehicle having a front-mounted engine.

Power transmitting system for a four-wheel drive motor vehicle


An electronic device includes a circuit board, a first microphone module, and a second microphone module. The first microphone module includes a first omnidirectional microphone connected to the circuit board, a first boot also connected to the circuit board, and a first tube extending from the first boot. The second microphone module includes a second omnidirectional microphone connected to the circuit board, a second boot also connected to the circuit board, and a second tube extending from the second boot. The first and second omnidirectional microphones are identical, and the first and second boots are identical.

1. Field of the Invention
The invention relates to a microphone array in a housing of an electronic device capable of adequate performance.
2. Description of the Related Art
A typical microphone array includes a number of microphones disposed in tandem. A simple example is shown in FIG. 1, wherein the microphone array 10 includes two microphones 11 and 12 placed side by side. Directivities of the microphone array 10 can be achieved by manipulating the signal received by the two microphones 11 and 12. Assuming the two microphones 11 and 12 are omni-directional and have the same characteristics, the directivity of the microphone array 10 depends on the distance D between the two microphones 11 and 12.
The disclosed microphones 11 and 12 are placed in an open space for achieving directivity. Most electronic devices (cellular phones, personal digital assistants, etc.), however, have plastic or metal housings, which are acoustic isolators. Acoustic isolators block audio signals increasing difficulty in placing microphones.


In a PET scanner, a method for processing coincidence data includes associating a selected portion of the coincidence data with one of a plurality of subspaces of a coincidence space; deriving, from the coincidence data associated with subspace, a contribution to be used in forming an image; and weighting the contribution by an amount that depends on a likelihood that the coincidence data associated with that subspace includes data indicative of trues.

A PET scanner includes a ring of detectors for detecting gamma-rays. For each pair of events detected by diametrically opposed detectors, these exists a probability that those events arose from a pair of gamma-rays received directly from within a patient. However, there also exists a probability that at least one of the received gamma-rays was scattered on its way to the detector, or that the gamma-rays did not even arise from the same annihilation event.
In rendering an image, the latter two types of event pairs contribute to noise. It is therefore desirable to suppress such noise when generating the image.

Diversity processing of coincidence data


A carriage is moved along a track by a motor connected in a first control loop to a carriage position sensor. The carriage carries a chassis which is coupled to it by a flexible linkage. The chassis carries an accelerometer connected by a second control loop independent of the first control loop to a linear actuator acting on the chassis and bearing on the carriage. The chassis carries a primary mirror fastened to it and a secondary mirror coupled to it by a piezo-electric actuator controlled via a third control loop by an optical path difference OPD error signal generated in the recombination station that includes the interferometer. The third control loop is desaturated by the first or second control loop, preferably by the second control loop. The preferably stellar interferometer may be on board a spacecraft.

1. Field of the Invention
The present invention concerns the highly accurate control (to within a few nanometers) of movement of an optical component of a cat's eye delay line in a stellar interferometer system. It is more generally concerned with an interferometer device such as a FOURIER TRANSFORM SPECTROMETER in which, in addition to dynamic stabilization of the optical component during programmed movement to eliminate the effect of vibration, disruptive optical path differences generated independently of the optical component and its movement in the remainder of the interferometer device or exterior thereto are compensated.
Programmed vibration-free displacement of this kind is needed, for example, to control an optical delay line within a coherent recombination type stellar interferometer. In this case, where the distance (called the base) between the telescopes is in the order of 100 meters, equalizing the optical paths, despite the rotation of the Earth, requires displacement of the retro-reflector device of the optical delay line over a distance of several meters, at a speed of several tens of millimeters per second, with an average positional accuracy of a few microns and with an instantaneous accuracy (during a setting time of a few hundredths of a second) of a few nanometers (amplitude of the vibrations): the constraints are therefore more severe in respect of the dynamic error than in respect of the static error.
Such displacement characteristics are also necessary if the optical paths are equalized by moving the telescopes themselves.
2. Description of the Prior Art
The 1986 MIT thesis by R. W. HOLM entitled "A High Speed High-Resolution Optical Delay Line for Stellar Interferometry Applications" discloses a device for displacing a "cat's eye" in a delay line comprising a slave carriage moving on rails and comprising a chassis mobile on flexible pivots to which the cat's eye is fixed.
The secondary mirror of the cat's eye is carried by a piezo-electric actuator. The position of the mobile chassis relative to the carriage is controlled by a displacement detector and a loudspeaker voice coil type linear actuator. Finally, the carriage is moved by a stepper motor.
The optical path introduced by the delay line is measured by a laser interferometer. The error signal is injected into the control loop of the piezo-electric actuator. Saturation of this actuator is avoided by the action of the linear actuator and saturation of the linear actuator is avoided by the action of the stepper motor (hence the above use of the term "slave"). There are therefore three control loops nested one within the other.
This displacement device makes it possible to achieve vibration-free displacement of the cat's eye similar to friction-free displacement. It offers good performance because the error signal corresponds directly to the magnitude to be controlled, that is to say to the optical path.
On the other hand, it is ill suited to high speeds because the laser measurement system would then have to have a resolution of a few nanometers while the ratio of the maximum speed of variation of the optical path of the carriage to the resolution is limited by the electronic circuitry for reasons of feasibility.
Also, the piezo-electric actuator cannot apply sufficient force for this device to be applicable to the movement of large masses such as telescopes.
Finally, this device is costly because of the presence of the three control loops and because of the need to have a high-performance laser measurement system which can only function correctly in a vacuum.
A device of this type is described in the publication: P. CONNES 1975 Applied Optics, Volume 14 No 9, p 2067-2084.
The Kachler et al U.S. Pat. No. 5,008,606 describes a device for programmed movement of a carriage carrying via a flexible coupling a payload which must be moved without vibration over a long travel and at high speeds. This device is of the kind used for the delay lines of a stellar interferometer and is free of the drawbacks mentioned above.
This document discloses a vibration-free displacement control device suitable for static and dynamic control of a mobile optical element movable along one direction in an interferometer device comprising a guide track, a carriage carrying a payload including said optical element and movable along said guide track, a motor by which said carriage is driven along said guide track, drive control means connected to said drive motor and adapted to move said carriage according to a predetermined law, flexible linkage means between said payload and said carriage enabling relative movement between said payload and said carriage parallel to said direction of displacement of said optical element, and at least one actuator adapted to act on at least part of the optical element under the control of at least one stabilization control loop connected to at least a second sensor, the device being characterized in that the stabilization control loop is independent of the drive control means, in that the second sensor is an accelerometer carried by the payload and responsive to acceleration of the payload parallel to said direction of displacement of said optical element, in that the actuator acts on all of the payload while bearing on the carriage, in that the stabilization control loop includes filter means for filtering signals from the accelerometer, and in that the drive control means comprises a control loop connected to a position sensor adapted to sense the position of the carriage on the guide track.
In practice the payload is provided with an accelerometer measuring acceleration in the direction of displacement of the carriage and carries a primary element of a linear electromagnetic actuator the secondary element of which is fixed to the carriage and the force applied by the linear motor is controlled by the signal from the accelerometer so that vibrations of the carriage are not transmitted to the payload.
Preferred features of the document included:
the filter means of the stabilization control loop was a second order filter having a transfer function F(p) of the form: ##EQU1## the accelerometer was of the piezo-electric or slaved pendulum type, the actuator was of the voice coil type, PA1 the guide track used crossed rollers, PA1 the drive motor was a brushless linear motor, PA1 the position sensor was an incremental type sensor, PA1 the drive control loop was a digital position/speed control loop, PA1 the optical element was a "cat's eye" retro-reflector in a delay line, PA1 the optical element was one of the telescopes of a stellar interferometer, mobile towards a recombination station. PA1 slow drift in pointing in the case of an interferometer device on board a spacecraft, PA1 vibrational deformations (at frequencies in the order of 10 Hz, for example) possibly due to flexibility of the spacecraft, PA1 atmospheric turbulence in the case of ground observations. PA1 a carriage carrying a chassis to which said primary mirror is fastened and which is movable along said guide track, a motor for driving said carriage along said guide track, a first drive motor control loop connected to a position sensor adapted to sense the position of said carriage on said guide track to move said carriage in accordance with a predetermined set point law, PA1 flexible linkage members coupling said chassis to said carriage enabling relative movement between said carriage and said chassis parallel to said direction, at least one actuator adapted to bear onto said carriage and act on said chassis under the control of a second control loop independent of said first control loop and connected to a second sensor in the form of an accelerometer carried by said chassis and responsive to acceleration of said chassis parallel to said direction, PA1 wherein said secondary mirror is coupled to said chassis by a piezo-electric actuator acting on said secondary mirror parallel to said direction and controlled by a third control loop receiving as input an optical path error signal generated in said recombination station and delivering also to at least one of said first and second control loops an actuator desaturation signal. PA1 space qualification was problematical because of the laser (service life, reliability, sensitivity to environmental constraints), PA1 large travels (>30 meters) were difficult to obtain because of diffusion of the laser light over the reflective surfaces in the cat's eye, PA1 the cost of the laser measuring system and of adjusting the three nested loops, PA1 the risk of mixing of the laser signal with the stellar signals and therefore of pollution of the stellar astronomic signal.
This document also proposed a stellar interferometer comprising one or more movement control systems of the aforementioned type.
In practice the novelty of the invention resided notably in the fact that, to damp very effectively vibrations of an optical element mobile along a given path with given kinetic properties, it taught, in a way that went counter to the received wisdom of those skilled in the art, dispensing with any interconnection between the drive and stabilization control systems; surprisingly, the resulting great simplicity (and high reliability) were combined with excellent damping.
This solution enabled very accurate programmed movements of the cat's eye over long distances (up to 100 m) without requiring laser measuring techniques.
An object of the present invention is to improve the teachings of U.S. Pat. No. 5,008,606 by further enabling real time compensation of disturbances due to random and unknown optical path differences generated upstream or downstream of the delay line, possible sources of such disturbances including:

Interferometer device, in particular a stellar interferometer device, incorporating a delay line

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