A catadioptric camera having a perspective camera and multiple curved mirrors, images the multiple curved mirrors and uses the epsilon constraint to establish a vertical parallax between points in one mirror and their corresponding reflection in another. An ASIFT transform is applied to all the mirror images to establish a collection of corresponding feature points, and edge detection is applied on mirror images to identify edge pixels. A first edge pixel in a first imaged mirror is selected, its nearest feature points are identified, and a rigid transform is applied to them. The rigid transform is fitted to corresponding feature points in a second imaged mirror. The closest edge pixel to the expected location as determined by the fitted rigid transform is identified, and its distance to the vertical parallax is determined. If the distance is not greater than predefined maximum, then it is deemed correlate to the edge pixel in the first imaged mirror.

1. Field of Invention
The present invention generally relates to matching pixel points in multiple images having different view angles, and more specifically relates to edge pixel matching in multiple images taken with catadioptric cameras.
2. Description of Related Art
Edge detection algorithms are part of many image manipulation operations. Edge detection is fundamental to image processing and computer vision, particularly in the areas of feature detection and feature extraction. Edge detection aims to identify points, i.e. pixels that outline objects within an image. There are many edge detection algorithms, but generally they attempt to identify pixels at which discontinuities occurs, i.e. where the image brightness changes sharply. In the ideal case, the result of applying an edge detector to an image leads to a set of connected curves that indicate the boundaries of objects, the boundaries of surface markings, and discontinuities in surface orientation. Once the boundaries have been identified, various image processing operations may be applied to the digital image.
For example FIG. 1A shows a typical digital image, and FIG. 1B shows the results of applying edge detection to the image of FIG. 1A. Edge detection may be designed to identify thick or thin lines, or may be optimized to separately identify thick and thin lines. In the example of FIG. 1B, both thick and thin lines are separately identified, which permits them to be separately processed. This permits the processing of the digital image to be more specialized by adjusting the size of a pixel-processing window according to line thickness. As a result, application of a specific image processing algorithms, such a bilateral filter, may be optimized along the edge of objects according to line thickness to achieve a sharper final image, as shown in FIG. 1C.
Another use of edge detection is feature detection. As an example, if one has a library of identifying features of a specific object, then one may search an input digital image for those identifying features in an effort to determine if an example of the specific object is present in the input digital image. When this is extended to multiple digital images of a common scene taken from different view angles, it is possible to index, i.e. match or correlate, feature points from one image to the other. This permits the combined processing of the multiple digital images.
For example in FIG. 2, images 2, 4, 6 and 8 each provide partial, and overlapping, views of a building in a real-world scene, but none provide a full view of the entire building. However, by applying edge detection and indexing (i.e. identifying matching pairs of) feature points in the four partial images 2, 4, 6 and 8 that correlate to the same real feature point in the real-world scene, it is possible to stitch together the four partial images (i.e. applying an image stitching tool) to create one composite image 10 of the entire building. The four partial images 2-8 of FIG. 2 are taken from the same view angle, but this approach may be extended to the field of correspondence matching, where images of a common scene are taken from different view angles.
In the field of computer vision, correspondence matching (or the correspondence problem) refers to the matching of objects (or object features or feature points) common to two, or more, images. Correspondence matching tries to figure out which parts of a first image correspond to (i.e. are matched to) which parts of a second image, assuming that the second image was taken after the camera had moved, time had elapsed, and/or the pictured objects had moved. For example, the first image may be of a real-world scene taken from a first view angle with a first field of vision, FOV, and the second image may be of the same scene taken from a second view angle with a second FOV. Assuming that the first and second FOVs at least partially overlap, correspondence matching refers to the matching of common features points in the overlapped portions of the first and second images.
Correspondence matching is an essential problem in computer vision, especially in stereo vision, view synthesis, and 3D reconstruction. Assuming that a number of image features, or objects, in two images taken from two view angles have been matched, epipolar geometry may be used to identify the positional relationship between the matched image features to achieve stereo view, synthesis or 3D reconstruction.
Epipolar geometry is basically the geometry of stereo vision. For example in FIG. 3, two cameras 11 and 13 create 2D images 15 and 17, respectively, of a common 3D scene 10 consisting of a larger sphere 19 and a smaller sphere 21. 2D images 15 and 17 are taken from two distinct view angles 23 and 25. Epipolar geometry describes the geometric relations between points in 3D scene 10 (for example spheres 19 and 21) and their relative projections in 2D images 15 and 17. These geometric relationships lead to constraints between the image points, which are the basis for epipolar constraints, or stereo constraints, described more fully below.
FIG. 3 illustrates a horizontal parallax where, from the view point of camera 11, smaller sphere 21 appears to be in front of larger sphere 19 (as shown in 2D image 15), but from the view point of camera 13, smaller sphere 21 appears to be some distance to the side of larger sphere 19 (as shown in 2D image 17). Nonetheless, since both 2D images 15 and 17 are of a common 3D scene 10, both are truthful representations of the relative positions of larger sphere 19 and smaller sphere 21. The geometric positional relationships between camera 11, camera 13, smaller sphere 21 and larger sphere 19 thus establish geometric constraints on 2D images 15 and 17 that permit one to reconstruct the 3D scene 10 given only the 2D images 15 and 17, as long as the epipolar, or stereo, constraints are known.
Epipolar geometry is based on the pinhole camera model, a simplified representation of which is shown in FIG. 4. In the pinhole camera model, cameras are represented by a point, such as left point OL and right point OR, at each respective camera's focal point. Point P represents the point of interest in the 3D scene being imaged, which in the present example is represented by two crisscrossed lines.
Typically, the image plane (i.e. the plane on which a 2D representation of the imaged 3D scene is captured) is behind a camera's focal point and is inverted. For ease of explanation, and to avoid the complications of a an inverted captured image, two virtual image planes, ImgL and ImgR, are shown in front of their respective focal points, OL and OR, to show non-inverted representations of captured images. Point PL is the 2D projection of point P onto left virtual image ImgL, and point PR is the 2D projection of point P onto right virtual image ImgR. This conversion from 3D to 2D may be termed a perspective projection, and is described by the pinhole camera model, as it is known in the art. It is common to model this projection operation by rays that emanate from a camera and pass through its focal point. Each modeled emanating ray would correspond to a single point in the captured image. In the present example, these emanating rays are indicated by dotted lines 27 and 29.
Epipolar geometry also defines the constraints relating the positions of each camera relative to each other. This may be done by means of the relative positions of focal points OL and OR. The focal point of a first camera would project onto a distinct point on the image plane of a second camera, and vise-versa. In the present example, focal point OR projects onto image point EL on virtual image plane ImgL, and focal point OL projects onto image point ER on virtual image plane ImgR. Image points EL and ER are termed epipoles, or epipole points. The epipoles and the focal points they project from lie on a single line, i.e. line 31.
Line 27, from focal OL to point P is seen as a single point, PL in virtual image plane ImgL, because point P is directly in front of focal point OL. This is similar to how image 15 of camera 11, in FIG. 3, shows smaller sphere 21 in front of larger sphere 19. However, from focal point OR, the same line 27 from OL to point P is seen a displacement line 33 from image point ER to point PR. This is similar to how image 17 of camera 13, in FIG. 3, shows smaller sphere 21 displaced to the side of larger sphere 19. This displacement line 33 may be termed an epipolar line. Conversely from focal point OR, line 29 is seen as a single point PR in virtual image plane ImgR, but from focal point OL line 29 is seen as displacement line, or epipolar line, 35 on virtual image plane ImgL.
Epipolar geometry thus forms the basis for triangulation. For example, assuming that the relative translation and rotation of cameras OR and OL are known, if projection point PL on left virtual image plane ImgL is known, then the epipolar line 33 on the right virtual image plane ImgR is known by epipolar geometry. Furthermore, point P must projects onto the right virtual image plane ImgR at a point PR that lies on this specific epipolar line, 33. Essentially, for each point observed in one image plane, the same point must be observed in another image plane on a known epipolar line. This provides an epipolar constraint that corresponding image points on different image planes must satisfy.
Another epipolar constraint may be defined as follows. If projection points PL and PR are known, their corresponding projection lines 27 and 29 are also known. Furthermore, if projection points PL and PR correspond to the same 3D point P, then their projection lines 27 and 29 must intersect precisely at 3D point P. This means that the position of 3D point P can be calculated from the 2D coordinates of the two projection points PL and PR. This process is called triangulation.
As is explained above, however, epipolar geometry and the stereo constraint are based on the pinhole camera model, and thus do not apply to cameras that do not adhere to the pinhole camera model. Consequently, the availability of corresponding matching tools for non-pinhole cameras has been limited.
Examples of cameras that do not adhere to the pinhole model are orthographic cameras, pushbroom cameras, cross-slit cameras and catadioptric cameras. Such cameras, however, typically provide a larger field of vision than is possible with pinhole cameras.
It would be desirable to facilitate the extension of correspondence matching to the larger field of vision available to non-pinhole cameras, and in particular to catadioptric cameras.

Context and epsilon stereo constrained correspondence matching


In a radiographic image connection processing method of connecting plural partial radiographic images, the partial radiographic images are selected, and if appropriate the operation mode is changed, e.g., from an image position adjustment mode, for adjusting a position of the selected partial radiographic image, to an image measurement mode, for measuring the selected partial radiographic image, or vice versa. The selected partial radiographic images are connected. Thus, it is possible to achieve image position adjustment and image measurement during radiographic image connection, and it is also possible to achieve smooth performance of the operations for image position adjustment and image measurement.

1. Field of the Invention
The present invention relates to a radiographic image connection processing method, a radiographic image connection processing apparatus, a computer program for executing the radiographic image connection processing method, and a computer-readable recording medium storing the computer program for executing the radiographic image connection processing method. In particular, the present invention relates to a technique which is suitable for generating a whole image based on plural partial radiographic images generated from a common subject portion.
2. Related Background Art
Conventionally, a so-called radiographic image diagnosis which obtains an image of a patient by using electromagnetic radiation (X-rays) and thus obtains internal information about the patient is widely executed. Here, in conventional radiography, a film is held together with an intensifying screen in a cassette, a patient is photographed using radiation rays, and the photographed film is developed, whereby a radiographic image of the patient is obtained.
The size of the film to be used at that time is standardized, and the maximum film that is generally and widely used is a so-called half-size film, having the size 14 inches×17 inches.
In a case where so-called lower limb whole-length photographing or whole spine (or backbone) photographing, which aims to measure a bone, is performed, the half-size film of 14 inches×17 inches is too small in size to be used. Thus, in that case, there is used a method in which a so-called long cassette capable of holding a long film is used to photograph a whole-length lower limb or a whole spine and thus obtain the image thereof on the long film. However, even in that case, another method may be adopted because it is hard for an operator to deal with the long film when developing it. In this alternative method, plural half-size films (each 14 inches×17 inches) are held in the long cassette so that the successive films partially overlap each other, and the image obtained by photographing the whole-length lower limb or the whole spine is formed on these films. Further, in this method, the films on which the photographed image has been formed are developed one by one, and then the developed images are appropriately connected with each other using adhesive tape or the like, to obtain the whole image.
On one hand, in recent years, an apparatus which can directly photograph a subject and thus obtain a radiographic image thereof as a digital image has been developed. Japanese Patent Application Laid-Opens Nos. S55-012429 and S63-189853 and the like disclose, e.g., a method in which a photostimulable phosphor detector is used as an apparatus for detecting an amount of radiation irradiated on the subject and then forming as an electrical signal the radiographic image in correspondence with the detected amount of the radiation.
In the apparatus like this, photostimulable phosphor is applied or evaporated on and then fixed to a sheet-like substrate to form the photostimulable phosphor detector, and the radiation transmitted through the subject is irradiated on the formed detector, whereby the irradiated radiation is absorbed by the photostimulable phosphor. Then, the photostimulable phosphor is excited by light or heat energy, the radiation energy stored in the photostimulable phosphor as the result of the above absorption is emitted as fluorescence, and the emitted fluorescence is photoelectrically converted, thereby obtaining the electrical image signal.
In addition, Japanese Patent Application Laid-Open H03-287248 proposes a method of performing, e.g., whole spine photographing by using such an apparatus as above. In this method, more specifically, a long cumulative phosphor sheet which has a recording area corresponding to the length of the whole spine of a subject is used to perform the photographing.
Moreover, Japanese Patent Application Laid-Open No. H11-244269 proposes a method in which plural cassettes respectively holding photostimulable phosphor detectors are arranged partially overlapping each other, the cassettes are held in this arrangement in a special cassette holder, and the subject is photographed.
Japanese Patent Application Laid-Open No. H03-287249 proposes a method in which plural photostimulable phosphor detectors are arranged partially overlapping each other, a subject is photographed to obtain plural partial radiographic images, and then the partial radiographic data corresponding to these images are synthesized to generate a whole image.
On one hand, in recent years, an apparatus which can photograph a subject by using a semiconductor sensor and obtain a radiographic image thereof as a digital image is developed. More specifically, in this type of apparatus, which uses the semiconductor sensor, generally, phosphor is applied or adhered to the semiconductor sensor in advance. Thus, incident radiation is first converted into light by the applied or adhered phosphor, the converted light is detected by the semiconductor sensor, and the detected light is then photoelectrically converted into an electrical signal.
In the apparatus of this type, because the area photographable by the semiconductor sensor is limited or restricted, it is impossible to photograph the whole spine of a subject with one exposure. For this reason, the subject is photographed plural times to obtain plural partial radiographic images, the obtained plural images are displayed, and whole-image data, representing a single whole image, is then generated based on plural sets of partial radiographic image data corresponding to the displayed plural images.
Japanese Patent Application Laid-Open No. 2000-342567 proposes a method of generating whole-image data from plural partial radiographic image data respectively obtained by photographing a subject plural times. According to this method, generally, a user interactively generates the whole image data. More specifically, in a synthesis image generation step to be performed in this method, the radiographic image of the subject (target) is first displayed, the partial radiographic images to be synthesized are appropriately selected from the displayed image, the connection positions at which the successive partial radiographic images should be connected with others are designated respectively on the selected partial radiographic images, and the partial radiographic images are actually connected and synthesized on the basis of the designated connection positions, thereby generating a whole image. As described above, various examples for mutually synthesizing or connecting the plural partial radiographic images are proposed, but none of these examples mention a problem which may occur during in measuring the radiographic image.
In a case where plural radiographic images are connected as above, when position adjustment of the radiographic images and measurement of the radiographic images are simultaneously performed, there is a fear that the position adjustment of the images may shift immediately after the measurement of the images, and, in such a case, the connected and synthesized image is different from the measured result.
Moreover, in a case where a mark used for the position measurement and/or the measured result obtained by the position measurement are displayed on the radiographic images, there is a fear that the mark and/or the result remaining on the display may interfere with the position adjustment of the radiographic images and/or the measurement of the radiographic images, which are the intended purpose.
Furthermore, in a case where a distance extending across the successive radiographic images is measured and then an enlargement ratio of one of these images is changed, there is a fear that the accuracy of the measured result may suffer.

Radiographic image connection processing method, radiographic image connection processing apparatus, computer program, and computer-readable recording medium


A phase-locked loop (PLL) generates an oscillator signal based on an input reference signal. A voltage-to-current converter converts a control voltage to a first current. A current-controlled oscillator generates the oscillator signal based on the first current. A dual charge pump circuit generates first and second charge pump currents having a predetermined ratio, based on a second current generated by a current mirror circuit and an error (feedback) signal. An active loop filter generates the control voltage based on the first and second charge pump currents. The active loop filter includes an input capacitance that varies with a variation in the predetermined ratio of the charge pump currents. The active loop filter also includes a transconductance stage having a transconductance that varies based on a third current generated by a current mirror circuit. The PLL bandwidth is independent of PVT variations and dependent only on the frequency of the input reference signal. In addition, the size of the input capacitor is relatively small so that the circuit requires very little space.

The present invention relates generally to a system for generating an oscillator signal and, more particularly, to a phase-locked loop (PLL) for generating an oscillator signal.
A phase-locked loop (PLL) is a control system that generates an oscillator signal having a constant phase relationship with an input reference signal. PLLs are widely used in various applications such as radios, telecommunications, computers, and other electronic applications. A PLL includes a voltage-controlled oscillator (VCO) for generating the oscillator signal based on a control voltage, and a phase detector for comparing the phase of the oscillator signal with that of the input reference signal and for generating an error signal based on the detected phase difference. The PLL also includes a loop filter for filtering the error signal and generating the control voltage used by the VCO.
For stable operation, the bandwidth of the PLL is required to be dependent only on the frequency of the input reference signal. However, the bandwidth may vary with various other parameters, such as process, voltage and temperature (PVT) variations, loop division factor 'N', PLL design parameters and the like. These parameters introduce undesired variance into the PLL bandwidth and degrade the loop stability of the PLL. Further, the input capacitance of the loop filter is known to consume a substantial portion of the overall circuit area.
It would be advantageous to have a PLL whose bandwidth is independent of PVT variations, loop division factor, and PLL design parameters, and dependent only on the frequency of the input reference signal. It would be further advantageous to reduce the area consumed by the input capacitor used in the PLL loop filter.


An improved extrusion process is provided for the production of freezeable breadings which can be applied to frozen food products and which essentially eliminates the problem of "frosty tips", i.e., the tendency of prior extruded breadings to exhibit an unappealing whitish color when breaded products were fried or baked. The process of the invention involves first preparing a moisturized breading mixture containing a major proportion of wheat flour, together with water and active yeast; this mixture is then passed into and through an extruder under moderate conditions of temperature, pressure and shear, followed by shredding and drying of the extrudate to a moisture content of from about 8-12% by weight.

1. Field of the Invention
The present invention is broadly concerned with an improved process for the low cost extrusion production of breadings which can be applied to frozen foods such as fish and chicken. More particularly, the breadings of the invention eliminate the problem of "frosty tips", or the tendency of extrusion-produced breadings to give an unappealing, whitish appearance when applied to frozen foods which are ultimately baked or fried. The process of the invention involves use of a breading mixture containing flour, water and active yeast which is processed under relatively low temperature, shear, and pressure conditions within an extruder, followed by shredding and drying of the extrudate to yield the desired breadings.
2. Description of the Prior Art
Dry breadings are traditionally applied to a variety of foods such as fish, chicken and pork prior to cooking thereof. Further, such breadings are often applied to uncooked products prior to freezing so that the consumer may directly bake or fry the frozen item without the bother of breading application. Most breading products heretofore used in the context of frozen prepared foods have been traditionally prepared breads which have been shredded to yield breadings. However, breadings of this type are relatively expensive.
Attempts have been made in the past to extrude breadings. When initially applied to food products, such extruded breadings appear to be fully equivalent to their traditional counterparts. However, when such breadings are applied to foods subjected to freezing, the breadings tend to exhibit whitened outer tips when the frozen foods are cooked. This phenomenon is referred to in the art as "frosty tips", and has been the principal reason why food processors have not used the generally less expensive extrusion-produced breadings.

Extrusion process for the production of freezeable breading product


A system and method for cleansing a harbor are disclosed which utilize the natural wave-like surface behavior of a tide wave propagating up a natural harbor or bay. Surface elevation changes along the propagating wave provide hydrostatic pressure differentials which drive the system. The system includes a conduit which connects an open sea area with an inner harbor area. The conduit may be either positioned on the bottom of harbor so that it extends through the harbor bay or it may be positioned so that it cuts across or cuts through a strip of land separating the harbor from the open sea. The conduit inlet is positioned in the open sea area and the conduit outlet is positioned in the inner harbor area. The outlet has a one way valve which both allows water flow through the conduit from the open sea area directly into the inner harbor area and also prevents water flow in the conduit in the reverse direction. The one way valve may be automatically responsive to directional water flow in the conduit, differential tidal water pressures between the open sea area and the inner harbor area, or it may be actuated by a suitable power source.

The invention relates generally to systems and methods for cleansing harbors and more particularly to such systems and methods which utilize the forces produced by the tides to flush water through the harbor and thereby remove therefrom harbor contaminants which are suspended or dissolved in the harbor waters or which may be simply carried away by the forces of the water currents. The invention is particularly useful in harbors which do not have a river stream emptying thereinto and which therefore do not have a natural flushing system to cleanse the harbor.
Harbors without a river must rely instead on ocean tide action for cleaning. The effectiveness of the tide in replenishing polluted water is diminished by the absence of any inherent flow of water associated with the tide. In that sense the tide is similar to wind driven waves which manifest only minor flow of water. This minor actual water flow renders the un-modified tide action a poor general cleaning instrument.
Water movement near the harbor inlet moves in and out from the ocean and thus replenishes the inlet with clean water from the ocean. This therefore results in effective cleaning. However, the water substantially inside the inlet is not connected directly with ocean water. This water therefore tends to slosh aimlessly back and forth with the tide without yielding effective cleaning. The waters in the inner areas of the harbor are thus generally stagnant and pollutants consequently tend to accumulate unabated in these areas.
This invention utilizes the natural characteristics of the tide to establish and maintain clean water circulation throughout the entire harbor. This circulation bring clean water directly to the inner harbor, or back harbor, to replace stagnant water.
Consider the phenomenon that is the tide. The tide is caused primarily by cyclic forces provided by the gravitational pull of the moon on the ocean waters. In response to these gravitational forces the water surface seeks to follow the relative position of the moon with respect to the earth. However, the actual forward propagation velocity of the elevation changes is modified by the free velocity of propagation in water in response to external disturbances. This free velocity constitute the propagation velocity of the tide. It is equal to the square root of the product of the acceleration of gravity and the depth of the water.
The combination of cyclic gravitational forces with the free velocity of propagation combine to give the tide a natural, wave-like nature. Thus the tide propagates in the form of a series of crests and troughs similar to wind-driven waves. The wavelength, the distance from crest to crest, of the tide wave is determined by the propagation velocity in water and the lunar period according to well understood physical principles.
The change of surface elevation along the path of propagation resulting from the wave tide wave is a fundamental characteristic of tide behavior. This characteristic provides the fundamental underlying principle supporting this invention. These elevation changes result in corresponding hydrostatic pressure changes in the water along the path of propagation of the tide. A comparison of hydrostatic pressure between diverse points along the path produces a hydrostatic pressure differential, or head.
The instant invention relies on the natural head between points along the path of propagation and implements the invention by connecting a submerged pipe from one point along the propagation path to another. For example, if the pipe connects a tide crest with a through, then water will flow according to well understood hydraulic principles of flow of fluids.
The principle is completely general. Therefore, the invention as described would theoretically function equally well in an open ocean. It needs no artificial abstruction to generate a head; the generated hydraulic head is inherent in the propagation of the tide itself.
In practical terms the wavelength in an open ocean, measured in hundreds of miles, is prohibitively long to implement the invention there. However, in a small boat harbor, or in a wetlands area or bay, the water depths are such that the wavelengths are measured in miles or fractions of miles instead of hundreds of miles. This makes the invention entirely feasible in such a harbor. Therefore the applicant's invention does not need any dam means or artificially created constrictions which impedes shipping in a harbor for the purpose of generating a head.
Some prior art systems use the energy of water currents or waves to cleanse a harbor. An example of such a device is dislcosed in U.S. Pat. No. 833,543 to Parker. The Parker device uses the force of impact or dash of waves against a floating apron. The apron floats so that the top of the apron lies int he water surface. The waves, upon impact, splashes over the top of the apron and into a connecting reservoir behind the apron. The level of water in the reservoir consequently rises to produce a head that is at a wave-determined differential height relative to the sea level at a particular time. This differential head is used to effect flow of fresh sea water into the bay via a connective canal.
The apron of the Parker patent floats with the surface of the ocean water. It therefore also floats with the tide. Consequently, the reservoir behind the apron is independent of the tide. Thus, the Parker invention does not utilize the tide as a head producing agent.
The problem with the Parker patent is that it ignores the effects of tide variances within the bay. This may in fact render the method inoperable as the tide in the bay may be higher than the wave generated head of water.
Other types of prior art devices for cleansing harbors utilize reservoirs to collect waters moved by tidal flow. An example of such a device is disclosed in U.S. Pat. No. 4,162,864 to Maeda. The Maeda device uses one or more reservoirs to collect water brought therein by the tides.
Floodgates are also provided to control water flow into and out of the reservoirs. Appropriate floodgates are opened to release water from the reservoirs into the harbor when the reservoir waters have a head higher than the sea and when the tide has begun to ebb. However, a primary disadvantage with such a system is that construction of such reservoirs may be unreasonably expensive and operation and maintenance of the floodgates may also be inordinately expensive. In addition, the large size and number of the reservoirs take up valuable space in the harbor and may also interfere with normal usage of the harbor.
A harbor cleansing system is thus needed which can effectively flush water from stagnant (or dead water) areas of a harbor. A harbor cleansing system is also needed that is economical and neither requires a lot of harbor space nor interferes with normal harbor usage.

Tidal system and method for cleansing a harbor


A mattress including an air pressure indicator configured to indicate the pressure of the mattress.

The present invention relates to a mattress for a bed. More particularly, the present invention relates to a mattress including an indicator configured to provide an indication of the pressure of the mattress.
Beds, including mattresses, mattress overlays, mattress toppers, and mattress replacement systems having a plurality of air bladders or sacs to provide an adjustable patient support surface are well known in the art. Examples of inflatable patient supports are disclosed in U.S. Pat. No. 4,949,413 to Goodwin and U.S. Pat. No. 5,647,079 to Hakamiun et al., which are assigned to the assignee of the present invention and the disclosures of which are expressly incorporated by reference herein.
It is also known to provide hospital beds which perform functions such as the prevention/treatment of decubitus ulcers (bedsores), pulmonary rotational therapy, or percussion/vibration therapy. Additionally, it is known to use inflatable mattress with a variety of inflatable cell/zone structures. Illustrative functions of a mattress including cell/zone structures are disclosed in U.S. Provisional Application Ser. No. 60/567,215 to Balaton et. al., which is assigned to the assignee of the present invention and the disclosure of which is expressly incorporated by reference herein.
According to an illustrative embodiment of the present disclosure, a patient support apparatus is provided including a frame, a deck supported by the frame, a mattress, and a gauge. The gauge is coupled to the mattress and is configured to measure a mattress pressure. The gauge includes a push to read valve and an indicator. The indicator is configured to display a mattress pressure in response to actuation of the push to read valve.
According to another illustrative embodiment of the present disclosure, a pressure measuring device system is provided for use with a mattress. The pressure measuring device system is configured to determine a mattress pressure of the mattress. The pressure measuring device system comprises a measuring device, an indicator, and at least one sensor port coupled to the mattress and configured to receive the measuring device. The measuring device is configured to take a mattress pressure reading. The indicator is coupled to the measuring device and is configured to display the mattress pressure reading.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of illustrated embodiments exemplifying the best mode of carrying out the invention as presently perceived.

Mattress having an air pressure indicator


Systems and techniques for managing a user persona presented in a communication session. In response to a request from an originating user for a communication session, a persona manager for the originating user is invoked, examining request details and the nature and context of the requested communication session and selecting a persona for the user, selection of the persona being employed to indicate services associated with the communication. Similarly, in response to a request from an originating user for a communication session, a persona manager for the receiving user to whom the request is directed examines details of the request and the nature and context of the communication session and makes decisions relating to persona selection for the receiving user. The decision may involve accepting a persona indicated in the originating user's request, or selecting a different persona and creating routing a request to be routed to the receiving user.

The use of communication services, such as land and cellular telephony, text messaging, text, voice, and video instant messaging, and a host of other services, is of central and growing importance in the lives of many people, with many users of communication services taking on numerous different roles and employing many different communication devices and services in their day to day activities. Users may see themselves as acting in different roles in their different communications. These different roles involve interactions with different groups of people and often involve the use of different combinations of services commensurate with the different roles in which the users see themselves as acting.
It is advantageous to users to have flexibility in their communications, and it is highly desirable for service providers to afford users a wide range of services, without a need for a user to go to different providers for different services. Many providers therefore allow users to associate combinations of services with different service profiles, with a number of different service profiles being associated with a single user. A user may receive services from a provider through different devices, such as a landline telephone, a cellular telephone, a personal digital assistant, a computer, a set top box, and numerous other devices, and may establish communication sessions with other users through any of a number of devices.
Among its several aspects, the present invention recognizes the need for convenient and flexible selection of user personas to allow a user to operate in an appropriate role in a particular communication session with little or no regard for the particular mechanisms used to engage in the session. Modern users see themselves as engaging in interactions based on their needs at the time, and do not see themselves as operating in roles based on the equipment they happen to be using. In addition, users prefer to minimize the complexity of their interactions. For example, it is highly desirable to a user to deal with only a limited number of user IDs, or even only one user ID. At the same time, the user may wish to have access to a number of different services or sets of services that are selected based on an identity that the user wishes to assert for a particular interaction, and may wish that the choice of which identity to assert be made in a way that is relatively transparent to the user.
To address these issues, as well as others, a communication system according to an aspect of the present invention provides a persona manager used to analyze information and context surrounding a communication session and select a user persona based on the analysis. The user persona is suitably asserted in the form of a public user identifier (PUID) and the persona manager examines the circumstances of the initiation of a communication session and changes the PUID employed for the session as appropriate. A PUID is typically associated with a set of services to be employed or made available in the session.
A system stores a user profile for a user, associated with one or more PUIDs. Each PUID is associated with a service profile, which defines the services to be invoked in which the service profile is used, that is, in sessions in which the PUID associated with the service profile is asserted.
On many occasions, it may be desirable for a user to assert a particular PUID that may not necessarily be the default PUID associated with a particular mechanism for beginning a session. For example, a user device may be associated by default with a particular PUID. For example, the user's landline telephone may have a particular default PUID associated with it, so that making a call using the landline telephone may default to assertion of that PUID. To take another example, a shared landline telephone may assert a group PUID by default, but a particular user may be better served if an individual PUID for the user is asserted, and the circumstances under which the call is made, such as the date, time of day, or party being called, may provide insight into which PUID is appropriate.
Different PUIDs, as noted above, are associated with different service profiles, and the different PUIDs may suitably be associated with sets of services that are more suited to be invoked in one context or another. For example, one PUID might be associated with services suited to the user's work activities, and another PUID might be associated with services suited to the user's school activities. A user might wish to assert a different PUID from the default PUID, but it might not be convenient for the user to explicitly make such a choice, or the equipment that the user happens to be using for the session may not allow for convenient changing of the PUID.
In addition, a user receiving a call may wish for a different PUID to be asserted than that specified in the originating request, which typically includes the PUID for the originator and the PUID for the receiving user. The receiving user may wish to change treatment for a particular user, or may otherwise wish to change the service profile used in a communication from that associated with the PUID used in the request, and may find it convenient for this change to be accomplished automatically.
To this end, a communication system according to an aspect of the present invention provides for a persona manager, capable of selecting a user persona to be asserted in a session. The user persona selection is typically achieved by selecting the PUID to be asserted in the session, either by allowing a default PUID to be asserted or by changing the asserted PUID to another PUID, with the selection being made based on information useful for such selection, for example, information about the location of the user, time of day, originating user, receiving user, and other information indicating the context of a communication session. The communication system maintains one or more number of user profiles for each user, with each user profile being associated with one or more PUIDs. Each PUID is associated with a service profile and the service profile associated with a PUID determines which services are to be invoked during a communication session initiated using the PUID associated with the service profile.
When a communication session is initiated, the persona manager is invoked. The persona manager receives information associated with the initiation of the communication session, such as the PUID associated by default with equipment used to initiate the session, identification of a receiving user, such as a PUID for the receiving user included in the request to begin the session, as well as additional information, such as information related to the context in which the communication session is being conducted. For example, the time of day may be relevant to whether the student, work, or home persona for a user is to be invoked, the location from which the call is being made may be relevant to whether a leisure trip, business trip, home, or work persona is to be invoked, the party being called may be relevant to whether a work, home, student, known person, or stranger persona is to be invoked, to take a number of examples. Information may be obtained from any appropriate source from which it is available, such as the header of a session origination request, stored information or other information indicating the nature of the session, interactions with the user, or other sources. The persona manager selects the appropriate persona, suitably using a set of rules used to analyze the various information elements surrounding the communication session. The appropriate persona is selected, and a new origination request may be generated or the current request may be modified, asserting the PUID chosen by the persona manager for the session, so as to request that specified application servers provide the services to be invoked for the session. A further request is then generated, asserting the appropriate PUID and the services to be invoked.
A more complete understanding of the present invention, as well as further features and advantages of the invention, will be apparent from the following Detailed Description and the accompanying drawings.

This patent is subject to a terminal disclaimer.

Methods and apparatus for user persona management


In an embodiment, an electromagnetic reluctance actuator comprises: a core assembly including a plurality of magnetic cores arranged in a two-dimensional plane, each core comprised of ferromagnetic material and wound by a coil of conductive wire, the coils operable for producing magnetic flux density in response to electrical currents flowing in the coils, wherein the current in each coil flows in a direction that is opposite the currents flowing in adjacent coils; and an actuator, at least a portion of which comprises ferritic material magnetically coupled to the coils by a magnetic circuit, for producing mechanical force in response to the effect of magnetic flux on the portion, the portion of the actuator being mounted for movement relative to the core assembly.

Electromagnets usually include a number of closely spaced turns of wire or coil that create a magnetic field. The wire turns are wound around a magnetic core made from a ferromagnetic material. The magnetic core concentrates the magnetic flux to make a powerful electromagnet. The magnetic field can be changed by controlling the amount of electric current in the coil. The electromagnet requires a continuous supply of current to maintain the magnetic field. When current flows in the coil magnetic flux density is generated in the core material which can be concentrated in a single direction. Depending on the design of the electromagnet, the magnetic flux density can provide an attractive force (pull force) on a ferromagnetic target. This "pull" force can be used in electromagnetic reluctance actuators.
An electromagnetic reluctance actuator operates on the principle that a magnetic material, when placed in a magnetic field, will experience a mechanical force tending to move the material in a direction parallel to the field to minimize the system energy. At any point on the surface of the material the reluctance force is proportional to the square of the magnetic flux density B2 of the magnetic field experienced at that point, as shown in Equation [1]:
                                                        F              rel                        -                                          f                ma                            ·              A                                =                                                                      B                  2                                                A                                            2                                                  μ                  o                                                      =                                          Φ                2                                            2                                                  μ                  o                                                A                                                    ,                            [        1        ]            where Frel is reluctance force, fma is surface force density, A is the pole surface area, B is the magnetic flux density, Φ is magnetic flux and μo is vacuum permeability.
A typical design objective for electromagnetic reluctance actuator is to optimize the electromagnet design to delay magnetic field saturation. Magnetic field saturation is a state reached when an increase in an applied external magnetic field cannot increase the magnetization of the core material further, resulting in the total magnetic flux density leveling off. This may result in a force that is too weak for a particular application.


An airbag assembly in a vehicle is provided. The airbag assembly comprises a base and a housing to be inserted into the base. The housing includes a first connection part protruding from an outer wall of the housing and a second connection part extending from the first connection part and facing the outer wall and the base includes a first slot extending in a first direction and a second slot extending from the first slot at a second direction different from the first direction, and the first slot includes an open end to receive the first connection part. The housing is connected with the base when first connection part is received in the second slot.

For the convenience of replacement and maintenance, the parts in a vehicle are usually designed to be detachably connected with a vehicle panel. An airbag assembly is such an example of a vehicle part.
Current airbag assemblies usually comprise an installation base and a vehicles part. The installation base comprises a plurality of receiving slots, and the vehicle part comprises a plurality of elastic connection members corresponding to the plurality of the receiving slots. The connection member's free end has an extension disposed at a direction away from the vehicle parts. When the vehicle part is inserted into the installation base, the elastic connection member is deformed under a force until the extensions are pressed into the receiving slots. Such assembly needs sufficient force to clip or snap the vehicle part into its assembly position. Further, it is difficult to detach the vehicle part which is snap fitted with the installation base. Furthermore, due to a gap between the installation base and the vehicle part, a noise can be generated during the vehicle operation especially when driving on a bumpy road.


A buck regulator having a voltage sensor for sensing a voltage reversal caused by freewheeling current from an output inductor in the regulator. Upon sensing a reversed voltage, the voltage sensor triggers a gate controller to turn on a switch in the regulator, and thereby terminate a dead time. The voltage sensor and gate controller are high speed circuits, and therefore can reduce the duration of the dead time. Reducing the dead time duration improves efficiency by reducing the duration of body diode conduction. The dead time can be reduced to less than a turn-on time of the body diode, thereby preventing charge buildup in the body diode, and, consequently, preventing reverse recovery loss in the body diode. The present invention improves electrical conversion efficiency, and allows for increased operating frequency in buck regulators.

The present invention relates generally to electrical power supplies. More particularly, it relates to a method and apparatus for reducing dead time and reverse recovery losses in buck regulators to provide increased efficiency and higher operating frequency.
Buck regulators are commonly used in electronics for changing the voltage or polarity of a power supply. Buck regulators typically employ two electronic switches (typically MOSFETs) in combination with an output inductor. The switches are alternately turned on, thereby providing voltage pulses to the output inductor.
During portions (dead times) of the switching cycle, both switches are off. When both switches are off, the output inductor produces freewheeling current that flows through the integral body diode of one of the switches. Body diode current produces substantial energy loss due to the forward-bias voltage drop across the diode, thereby reducing the energy efficiency of the buck regulator. Additionally, reverse recovery loss occurs when the body diode later becomes reverse-biased. In order to improve the efficiency of buck regulators, body diode conduction and reverse recovery losses must be reduced.
In order to provide buck regulators with small size and weight, and reduced cost, it is best to operate the buck regulator at high frequency. However, energy loss from both body diode conduction and reverse recovery increase dramatically with increasing operating frequency. In this way, body diode conduction and reverse recovery tend to limit the maximum operating frequency of buck regulators.
It would be an advance in the art of buck regulator design to provide a buck regulator having greatly reduced dead time, and a greatly reduced or eliminated reverse recovery loss. Such a buck regulator could operate with very high efficiency compared to conventional buck regulators, and could operate at high frequency. High frequency capability can provide many benefits such as smaller size and weight, and reduced cost.
The present invention includes a buck regulator having an output inductor, first and second switches, a voltage sensor, and a gate controller. The first and second switches and the inductor are connected at a swing node. The voltage sensor is connected to the swing node and senses a voltage at the swing node. An output of the voltage sensor is connected to the gate controller. The gate controller controls the second switch in response to signals from the voltage sensor.
The gate controller may also control the first switch. In one embodiment, the voltage sensor triggers the gate controller in response to a voltage reversal of greater than 0.3 volts at the swing node.
The voltage sensor can comprise a bipolar transistor with an emitter connected to the swing node, and a collector connected to the gate controller. A base of the bipolar transistor may be connected to a voltage within about 0.7 volts of ground potential. The bipolar transistor may be made from a parasitic bipolar transistor integral to a lateral diffusion (LD) MOSFET, commonly used in power integrated circuits.
The voltage sensor can also comprise a first sense MOSFET and a second sense MOSFET connected in series. The first sense MOSFET is connected to the swing node, and the second sense MOSFET is connected to the gate controller. Also, a current amplifier can be connected between the second sense MOSFET and the gate controller.
The gate controller may control both first and second switches in response to the output of the voltage sensor. Specifically, the gate controller can turn on the second switch when the voltage sensor detects a voltage reversal at the swing node resulting from turn off of the first switch. Also, the gate controller can turn on the first switch when the voltage sensor detects a voltage change close to 0.7 volts at the swing node resulting from turn off of the second switch.
In another aspect of the present invention, the buck regulator comprises an output inductor, first and second switches, a gate controller, and a voltage sensor comprising a bipolar transistor with an emitter connected to the swing node, and a collector connected to the gate controller. The bipolar transistor can comprise a parasitic bipolar transistor integral to an LDMOSFET. The base of the bipolar transistor can be connected to a voltage within about 0.7 volts of ground potential.
In yet another aspect of the present invention, the buck regulator comprises an output inductor, first and second switches, a gate controller, and a voltage sensor comprising a first sense MOSFET connected to the swing node, and a second sense MOSFET connected in series with the first sense MOSFET. The first sense MOSFET has a gate connected to a reference voltage; the second sense MOSFET has a gate connected to a ground potential, or to a voltage within 0.7 volts of ground potential. A current amplifier can be connected between the second sense MOSFET and the gate controller. The second sense MOSFET can be a MOSFET.

Method and circuits for reducing dead time and reverse recovery loss in buck regulators

Virginia Tech Intellectual Properties, Inc.


At a conveying path 10 for continuously carrying a sheet material 1, an electron beam irradiation means 20 is arranged in opposition to at least one surface of the sheet material 1, and at least one surface of the sheet material 1 is sterilized using such an electron beam. The conveying path 10 takes shape of a hollow box surrounding the sheet material, and has an electron beam irradiation area 11 at a part of this area, while keeping a reduced-pressure state ranging from 10 to 80,000 Pa using a pressure reduction means 16. Further, the electron beam irradiation area 11 where the electron beam irradiation means 20 is arranged at least one sub area 12 at each of adjacent hollow box-shaped conveying path 10 at carry-in side and carry-out side of the sheet material, providing the pressure reduction means 16 for depressurizing the sub area 12.

As a usual method, a paper-made container (hereinafter referred to as "cartons") is widely used for packing liquid food like milk and juice. A sheet material for the carton is made by combining a cardboard made from pulp or similar raw material with a thin layer of heat-sealable plastic thereon or instead with a layer of aluminum foil thereon to keep liquid food in a sealed state for more extended period of time. These layers are laminated on at least such a surface of the cardboard as will become inner surface of a carton to which liquid food contacts when the cardboard is formed into the carton.
As commonly known, carton-packed food is shipped from a packing plant in the following manner: A sheet material in roll loaded on a payoff device is fed continuously into a carton forming line, in which line the sheet material is sized as designed and then folded into a desired shape of carton by a folding means. In the successive process, liquid food is filled into the carton thus formed and the filling port of the carton is sealed to complete packing process.
The sheet material for cartons is sterilized while travelling from the payoff device to the cartoning line and is transferred aseptically, a germfree condition without contamination, into the subsequent process.
Sterilization of sheet material conventionally used chemicals. This method however requires large scaled installations. Moreover, such method involves an anxiety about chemical residue on the sheet material sterilized. This anxiety therefore demands a process for a complete removal of chemicals from the sheet material. Consequently, an improvement has been desired in a sterilization device applicable to liquid food handling.
As a solution to this problem, an invention has been disclosed in JP2004-524895A1 (Patent Literature 1), which is known as a late alternative to a chemical sterilization apparatus for a sheet material. In Patent Literature 1, a unit for sterilization is proposed. The proposed unit is feasible for downsizing and efficiently sterilizes both surfaces of a sheet material with electron beam generated from an electron beam irradiation means while the sheet material is in high-speed transferring.
More specifically, the electron beam irradiation unit for sterilizing a sheet material defined in Patent Literature 1 has two electron beam irradiation means arranged across the sheet material facing each other in a part of a conveying path in the atmosphere. This arrangement radiates electron beam from each of the electron beam irradiation means to the sheet material in a high-speed transferring to sterilize both surfaces of the sheet material with electron beam. The sheet material thus sterilized is then transferred to the next stage of processing. Each of the electron beam irradiation means that generates low-energy electron beam accelerated at a voltage below 100 kV has its electron beam source enclosed by a vessel and has radiation shielding material such as lead plate installed inner wall of the vessel as a measure against X-rays that the electron beam source emits.
The above-stated electron beam irradiation unit for sterilizing a sheet material of a conventional style is able to efficiently sterilize both surfaces of sheet material. The unit however has a problem in that the unit is not compatible with such an electron beam irradiation means as works on a lower energy because such unit uses the electron beam irradiation means in the atmosphere in which electron beam having larger energy to certain degree is essential to sterilize.
Further, an electron beam irradiation means used in the atmosphere must have a radiation shielding material to shield X-rays emitted from the electron beam source of the irradiation means. This requirement results in a size-growth of the sterilization equipment as a whole possibly preventing the right positioning of the irradiation means on the sheet material conveying path.
Moreover, an electron beam irradiation means for use in the atmosphere easily generates plasma, which produces ozone (O3) from oxygen in the air.
The produced ozone, adhering to the sheet material sterilized, makes the sheet smell like ozone. Such smelling sheet material is not appropriate to a carton for liquid food packing. To remove the ozone odor, a measure such as lowering the oxygen concentration in the irradiation chamber by blowing nitrogen gas thereinto while electron beam irradiation is necessary; this arrangement makes the sterilization equipment sophisticated.
The object of the present invention is to provide an electron beam irradiation apparatus for sterilization of a sheet material. The device efficiently sterilizes at least one surface of a sheet material for a carton using a low-energy electron beam irradiation means under an appropriately regulated reduced-pressure atmosphere generating no ozone.

Electron beam irradiation apparatus for sterilizing sheet material


A method is followed to prepare a powder that includes carbon, silicon and boron, the silicon being in silicon carbide form and the boron being in boron carbide and/or free boron form. The method includes contacting a carbon-based precursor, a silicon-based precursor and a boron-based precursor BX3, X being a halogen atom, to obtain a mixture of these three precursors. The resulting mixture is subjected to laser pyrolysis. The boron-based precursor BX3 is heated, prior to the contacting step and/or simultaneously with the contacting step, to a temperature higher than the condensation temperature of the precursor.

Powders containing carbon, silicon and boron have been produced up until now using three types of techniques:                the mechanical alloying technique;        the technique using a solution route;        the technique using a thermal route.
The mechanical alloying technique consists of mechanically grinding submicron-size powders of silicon carbide (SiC) and boron carbide (B4C), in a device of crusher or ball mill type, for a sufficient time (often several hours) in an attempt to obtain a closely mixed powder having a silicon carbide phase and a boron carbide phase. However, no obtaining of powders of nanometric size has been reported using this technique. Moreover, the mechanical milling of powders may generate pollution of the resulting powders by elements originating from the milling device. As a result, the powders derived from this process cannot be used in applications requiring powders of high purity.
According to the solution technique, powders comprising carbon, silicon and boron are synthesized via sol-gel process using silicon-based precursors, carbon-based precursors and boron-based precursors. Such is the case in particular with the process described in Zhi-min et al. (Trans. Nonferrous Met. Soc. China, 16 (2006), 470-473), which respectively comprises:                a step to mix tetraethoxysilane, ethanol, sucrose and water;        a step to add tributyl borate to the resulting mixture, the pH being maintained until homogenization at a value of between 3 and 4;        a drying step in an oven at 60° C. to obtain a gel;        a carbothermal reducing step of the formed silica.
According to the technique via thermal route, the powders comprising carbon, silicon and boron can be prepared from gaseous precursors using different heat sources such as laser (in which case the term laser pyrolysis is used) or a plasma.
For example, Vassen et al. (Journal of Materials Science 31 (1996) 3623-3637), using laser pyrolysis, synthesized powders comprising carbon, silicon and boron from a mixture of precursors: SiH4—C2H4—B2H6 with a boron content not exceeding 4% by weight. This synthesis mode, inter alia, has the disadvantage of using diborane B2H6, which is an unstable gas of high cost, and on this account difficult to use for producing powders having higher boron contents than the above-mentioned content.
Guo et al. (Journal of Materials Science, 32 (1997), 5257-5269) synthesized powders comprising carbon, silicon and boron through the use of a thermal plasma from a mixture comprising solid silicon, boron trichloride BCl3 and methane CH4. The powders obtained with this synthesis mode comprise less than 4% by weight of boron and finally do not give any boron carbide phase (B4C) but boron nitride. The formation of boron nitride is generated by reaction of the nitrogen N2 derived from the plasma on the transiently formed boron carbide as per the following reaction:(½)B4C+N2→2BN+(½)C
In addition, the powders obtained with this method are of submicron size.
Other authors have endeavored to synthesize powders comprising carbon, silicon and boron using thermal plasma, in particular using a radiofrequency plasma torch, such as Saiki et al. in U.S. Pat. No. 4,847,060 starting from a mixture of reagents such as a mixture of SiCl4, CH4 and BCl3, and arriving at submicron powders having poor boron distribution in the particles of boron carbide and a boron content not exceeding 5% by weight.
On the basis of the drawbacks of prior art methods, the authors hereof have set themselves the objective of proposing a method for preparing powders comprising carbon, silicon and boron in the form of silicon carbide and boron carbide and/or boron alone, the said method being of simple implementation and low cost and which, by means of a reasoned combination of steps and reagents, allows powders to be obtained able to meet the following characteristics:                nanometric size of the constituent particles of the powder;        narrow size distribution;        a boron content which may be high (for example possible reaching 30% by weight relative to the total weight of the other elements present in the powder);        good dispersion of the silicon carbide and boron carbide phases;        controlled composition of the powder, in particular regarding the ratios Si/B, Si/C and B/C.

Method for preparing a powder comprising carbon, silicon and boron, the silicon being in silicon carbide form and the boron being in boron carbide form and/or boron alone

COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES


A semiconductor device includes a pad electrode layer and an align mark layer, formed on the semiconductor substrate. A passivation layer is formed on the semiconductor substrate and exposes at least a portion of the top of the pad electrode layer and at least a portion of the top of the align mark layer. A light-transmitting protecting layer covers at least a portion of the passivation layer, exposes the top portion of the pad electrode layer exposed from the passivation layer, and covers the portion of the align mark layer exposed from the passivation layer.

1. Technical Field
The present invention relates to a semiconductor device and a method of fabricating the same, and more particularly, to a semiconductor device having an alignment mark used as an alignment key in a packaging operation for semiconductor chips and a method of fabricating the same.
2. Discussion of the Related Art
Semiconductor devices formed on a semiconductor substrate are typically assembled for connection to external devices and also packaged to protect these semiconductor devices from the external environment. In particular, a semiconductor device may have a pad electrode layer used as an input/output terminal for being connected to an external device, and an alignment mark used as an alignment key for assembling the semiconductor device. For example, a semiconductor device used as a driving device of a LCD (liquid crystal display) device may be assembled on a glass substrate. This is known as the COG (chip on glass) assembly method.
According to the COG assembly method, the semiconductor device is aligned on the glass substrate, using an align mark. For example, as for the COG assembly method, "Panel Structure for Chip on Glass" of Korean Patent No. 0258719 can be referred. However, a conventional alignment mark structure for a semiconductor device may cause alignment errors when the processes change during a fabricating operation.
FIG. 1 is a cross-sectional view illustrating a semiconductor device having a conventional alignment mark structure.
Referring to FIG. 1, an align mark layer 55 is formed on a semiconductor substrate 50 and enclosed by a passivation layer 60. A polyimide layer 70 to protect the semiconductor device is formed on the passivation layer 60. The polimide layer 70 is patterned so as to expose the passivation layer 60 formed on the align mark layer 55. Generally, the align mark layer 55 is formed in a field region (not shown) which is formed of an insulating layer for isolation.
An optical alignment apparatus perceives the contrast between the field region and a portion of the align mark layer 55 and aligns a semiconductor device by using this contrast between the field region and the align mark layer 55. However, a thickness (h) deviation of the passivation layer 60 formed on the align mark layer 55 may change the color of the portion of the align mark layer 55, and this color change may result in an alignment error for these semiconductor devices. As optical alignment apparatus processes the alignment of a semiconductor device based upon the contrast between the field region and the align mark layer 55 within a standard range, these alignment apparatuses may as a result not achieve proper alignment for a semiconductor device having a contrast outside of the standard range.
The contrast of the passiviation layer 60 changes significantly according to the thickness (h) deviation of the passiviation layer 60. Thus, it may be difficult to control the contrast by controlling the thickness (h) of the passivation layer 60. Accordingly, even though the passivation layer 60 may be within an allowable process margin range, an alignment error with respect to the semiconductor device may still occur.
Thus, there is a need for a semiconductor device having reduced alignment error. In addition, there is also a need for a method of fabricating a semiconductor device that reduces alignment error during the assembly of the semiconductor device and that is cost-effective.

Semiconductor device having align mark layer and method of fabricating the same


A piezoelectric actuator includes a vibration plate which is joined to a flow passage unit to cover a pressure chamber formed in the flow passage unit, a piezoelectric layer arranged on the vibration plate, a first electrode arranged on the piezoelectric layer to face the pressure chamber, a second electrode arranged on the piezoelectric layer while being opposed to the first electrode, and a third area arranged in the remaining area of the piezoelectric layer opposed to the pressure chamber. A first portion of the piezoelectric layer interposed by the first and second electrodes is polarized in parallel to the thickness direction. A second portion of the piezoelectric layer disposed between the first and third electrodes in the plane direction, is polarized in parallel to the plane direction. Accordingly, there are provided the piezoelectric actuator having a high driving efficiency.

1. Field of the Invention
The present invention relates to a piezoelectric actuator, and a liquid transport apparatus provided with the piezoelectric actuator.
2. Description of the Related Art
Piezoelectric actuators have been hitherto known, which drive various objectives by utilizing the deformation of the piezoelectric layer (piezoelectric strain) brought about when the electric field is allowed to act. For example, Japanese Patent Application Laid-open No. 2006-304588 discloses a piezoelectric actuator for an ink-jet head, wherein the piezoelectric actuator is arranged on a surface of a flow passage unit including nozzles and pressure chambers, for applying the jetting pressure to the ink contained in the pressure chambers formed in the flow passage unit. The piezoelectric actuator is an actuator having the so-called unimorph structure. The piezoelectric actuator has a vibration plate which is made of metal and which is joined to one surface of the flow passage unit to cover the plurality of pressure chambers therewith, a piezoelectric layer which is stacked on the vibration plate, and individual electrodes which are formed in areas on a surface of the piezoelectric layer, the areas being opposed to central portions of the pressure chambers.
In this arrangement, the piezoelectric layer is polarized in the thickness direction. When a predetermined driving voltage is applied between the individual electrode and the vibration plate made of metal (common electrode), the electric field, which is parallel to the thickness direction as the direction of polarization, is allowed to act in the piezoelectric layer interposed by the individual electrode and the vibration plate. Accordingly, the piezoelectric layer is elongated or expanded in the thickness direction as the direction of polarization, and the piezoelectric layer is shrunk in the plane direction or the surface direction perpendicular to the direction of polarization. In this situation, the vibration plate is deformed so that the vibration plate is convex toward the side of the pressure chamber in the area facing the pressure chamber in accordance with the shrinkage deformation of the piezoelectric layer in the plane direction (unimorph deformation). Accordingly, the volume in the pressure chamber is decreased, and the pressure is applied to the ink contained in the pressure chamber.
The piezoelectric actuator, which has the conventional unimorph structure as described in Japanese Patent Application Laid-open No. 2006-304588, has involved such a problem that the driving efficiency is low. That is, it is necessary that the high driving voltage (difference in electric potential) should be applied between the individual electrode and the vibration plate in order to generate, in the vibration plate, a predetermined amount of the deformation required to apply the desired jetting pressure to the ink. As a result, a problem arises such that the electric power consumption of the actuator is raised or increased.

Piezoelectric actuator and liquid transport apparatus provided with piezoelectric actuator


A semiconductor package and a manufacturing method thereof are provided. The semiconductor package includes first and second package components stacked upon and electrically connected to each other. The first package component includes first and second conductive bumps, the second package component includes third and fourth conductive bumps, and dimensions of the first and second conductive bumps are less than those of the third and fourth conductive bumps. The semiconductor package includes a first joint structure partially wrapping the first conductive bump and the third conductive bump, and a second joint structure partially wrapping the second conductive bump and the fourth conductive bump. A curvature of the first joint structure is different from a curvature of the second joint structure.

In recent years, the semiconductor industry has experienced rapid growth due to continuous improvement in integration density of various electronic components, e.g., transistors, diodes, resistors, capacitors, etc. For the most part, this improvement in integration density has come from successive reductions in minimum feature size, which allows more components to be integrated into a given area. These smaller electronic components also require smaller packages that occupy less area than previous packages. Thus, new packaging technologies have begun to be developed. For example, some packages rely on bumps of solder to provide an electrical connection, and the different layers making up the interconnection in the packages have different coefficients of thermal expansion (CTEs). As a result, a relatively large stress derived from this difference is exhibited on the joint area, which causes the risk of delamination and/or cold joint. These relatively new types of packaging technologies for semiconductor devices face manufacturing challenges.

Joint structure in semiconductor package and manufacturing method thereof

Taiwan Semiconductor Manufacturing Company, Ltd.


A dynamic focusing electron gun for high resolution includes a triode part and a main lens. The main lens includes a first focusing electrode disposed proximate the triode part, a second focusing electrode disposed proximate an anode electrode, a static potential electrode and a dynamic potential electrode disposed between the first and second focusing electrodes to form a dynamic quadrupole lens. The dynamic focusing electron gun produces a high resolution image with a small radius beam spot with low astigmatism, low spherical aberration, and good voltage endurance characteristics.

Among the dynamic focusing electron guns, there is one which has a quadrupole lens as shown in FIG. 1. Said the electron gun comprises a prepositioned triode part consisting of cathode K, control grid G1 and screen grid G2, and a main lens system consisting of focusing electrode E1, dynamic electrode E2 and anode E3 which respectively receive a static focusing voltage, a dynamic focusing voltage, and a static anode high voltage.
On the beam exiting side of said focusing electrode E1 and on the beam entrance side of said dynamic electrode E2, vertically elongate beam passing holes H1 and laterally elongate beam passing holes H2 respectively are disposed facing each other to form a quadrupole lens. On the beam exiting side of said electrode E2 and on the beam entrance side of said anode E3, elongate common beam passing holes H2' and H3 are disposed. Isolating metal ribs 12, 12 and I3, I3 are vertically attached to the exit and entrance sides of the electrode E2 and the anode E3, respectively, to form three separate beam passing zones in holes H2' and H3.
Besides, in a conventional dynamic focusing electron gun constructed as described above, the dynamic electrode receives a parabolic dynamic focusing voltage which is synchronized with the horizontal and vertical scanning signals according to the scanning position of electron beam. The dynamic focusing voltage is applied to the dynamic electrode in addition to a static potential focusing voltage in such a manner that, when the electron beam lands on the central part of the screen, a dynamic voltage Vd of OV or low positive potential is applied, and when the electron beam lands on the periphery of screen, a high potential dynamic voltage is applied. Therefore, whether or not a quadripole dynamic lens is formed between the focusing electrode E1 and the dynamic electrode E2 is determined by the landing position of the electron beam. Thus, when a quadrupole lens is formed when the electron beam is scanned on the periphery of the screen, the electron beam becomes vertically elongated by the asymmetrical dynamic electric field formed by the vertically elongate beam passing holes H1,H1,H1 and laterally elongate beam passing holes H2,H2,H2.
The vertically elongated electron beam scanned toward the periphery of the screen passes through the deflection yoke for rectification of the distortion of the beam by a non-homogeneous magnetic field, with the result that a nearly complete circular beam spot is formed on the screen. Moreover, when the electron beam lands on the periphery of the screen, said dynamic voltage rises and thereby the strength of final acceleration and focusing lens formed between the dynamic electrode and the anode becomes weaker.
Thus, the focal distance of the electron beam becomes longer so that the focus of the electron beam is formed on the periphery of the screen which is farther from the electron gun than the central part of the screen and the beam spot formed on the screen becomes very small, thereby realizing high resolution of image.
However, there are shortcomings in the conventional dynamic focusing electron gun in that it is difficult to realize a voltage controlling device which can endure the high parabolic dynamic voltage, the static focusing, voltage must be applied to the dynamic electrode, and an arc may occur at the neck of the cathode ray tube by the leakage of current due to the high voltage. Further, the conventional dynamic focusing electron gun has two focusing electrodes, and therefore the magnification of the major lens which finally accelerates and focuses the electron beam must be increased. Thus, there is a fear that the quality of image will become worse because of spherical aberration due to the high magnification of the major lens.


A capacitor element (20) for a power capacitor with a dielectric film layer (3) and an electrode layet arranged on each flat side of the film layer, which electrode layers are divided into at least three metallized areas (4, 9, 10), separate from each other, in order to form an inner series connection arranged to conduct a load current, of which thee areas at least one is divided into segments (5) separated by non-metallized sections (6), and at least one bridge (7) arranged to electrically connect two of the segments together. In accordance with the invention the bridge is so arranged that, in the area divided into segments, the load current appears substantially only in the segments. The invention also relates to a power capacitor with such a capacitor element and also a metallized tape for such a power capacitor.

The present invention relates to a capacitor element for a power capacitor, including at least one elongated film layer of dielectric material, and an electrode layer of metal material arranged on each flat side of the film layer, which two electrode layers are divided into at least three metallized areas, separated from each other, in order to form an inner series connection arranged to conduct a load current. The three areas extend in the longitudinal direction of the film layer and at least one area of said at least three areas is divided into segments separated by non-metallized sections, and at least one bridge arranged to electrically connect two of the segments together.
The invention also relates to a power capacitor comprising such a capacitor element and also a metallized tape for such a power capacitor.
In this context power capacitors refers to capacitors for alternating or direct current applications for voltages exceeding 1 kV, preferably at least 5 kV.
In power capacitors it is known to use rolled capacitor elements comprising metallized tapes formed from sandwiched films of dielectric material and electrode layers of metal material. It is also known to divide the electrode layer into electrically separated, parallel metallized areas extending in the longitudinal direction of the films, in order to achieve series-connected part-capacitors between the end surfaces of the roll, known as xe2x80x9cinner series connectionxe2x80x9d. It is further more known to divide one or more of the metallized areas into segments separated by non-metallized sections, and also bridges arranged to electrically connect the segments together. Segmentation increases the equivalent surface resistivity of the metallized area, which has been found to benefit the so called xe2x80x9cself-healingxe2x80x9d capacity of the capacitor element. This means that in the event of an electric puncture in a film layer, the electrode material nearest the fault point is vaporized due to a powerful, but brief, discharge current endeavouring to pass the short circuit. The electric strength in the area is restored when the electrode material nearest the fault point has vaporized, and the capacitor element has thus self-healed. As a result of the lost electrode area, every self-healing process produces a slight decrease in the capacitance of the capacitor element. If a self-healing process occurs in a segment, the bridges ensure that sufficient energy can be transferred from adjacent elements to enable efficient vaporization of the electrode material around the fault point. If a serious fault occurs, e.g. if the puncture passes through several film layers, a strong current surge occurs through the bridges connected to the defective segment. If the current surge is sufficiently strong the bridges themselves may be vaporized, in which case the faulty segment is isolated. The lose in capacitance is in this case greater than at the self-healing process.
A segmented, metallized tape for a capacitor element of the above type is described, for instance, in the document GB 2 298 962A in connection with FIG. 4. The tape described consists of a film on which two segmented, metallized areas are arranged. Each segment is connected by bridges to two of its neighbouring segments. The metallized film is in this case intended for a capacitor element with one inner series connection.
During operation the rolled capacitor element is electrically connected at both its end surfaces and a current, in the following termed load current, flows continuously between these surfaces and causes Joule losses in the capacitor element. The load current follows the path of least resistance between the end surfaces. In the case of alternating current the alternating current itself is responsible for a considerable proportion of the Joule losses and in the case of direct current, ripple currents are responsible for most of the Joule losses. One problem with capacitor elements comprising known metallized tape of the type described above is that Joule losses occur in the bridges during normal operation. This is particularly so in applications involving high current. The generation of heat in known capacitor elements with metallized tape of the above type may be so great that it determines the dimensions of their design.
One object of the present invention is to eliminate the above-mentioned problems and provide a capacitor element comprising a segmented, metallized area where two adjacent segments are electrically connected by means of a bridge in accordance with a new principle.
The capacitor element and the power capacitor in accordance with the invention provide the bridge so arranged that the load current in the area divided into segments appears primariry in segments.
The metallized tape in accordance with the invention provides that at least one of the bridges is arranged in a portion of the non-metallized section that extends perpendicularly or substantially perpendicularly to the long sides of the dielectric film.
In accordance with the invention the bridge is arranged so that the load current appearing in the capacitor element does not pass through this to any great extent. However, the bridge is arranged so that a certain current exchange is permitted between neighbouring segments, e.g. at self-healing processes or in order to equalize small differences in potential. Contrary to the load current, the currents at these current exchanges are so low or of such short duration that they do not cause any great Joule losses.
In accordance with one embodiment of the invention the bridges are arranged in parts of non-metallized sections extending perpendicularly or substantially perpendicularly to the connection surfaces of the capacitor element. Since the load current strives to follow as xe2x80x9cstraightxe2x80x9d a current path as possible, i.e. strives to follow an electric circuit extending perpendicularly to the connection surfaces of the capacitor elements, forming the shortest path between the connection surfaces, a bridge that connects together two segments perpendicularly to this electric circuit will not be included in the electric circuit of the load current. This embodiment of the invention also contributes to a high resistance perpendicular to the direction of the load current, which is beneficial.
In accordance with another embodiment of the invention the segments connected together by the bridge are uniform.
In accordance with one embodiment of the power capacitor according to the invention, the power capacitor comprises a plurality of capacitor elements, that have substantially circular-cylindrical shape, are arranged close together so that their axial directions coincide, and are connected to each other so that they form a series-connected capacitor stack. In such a power capacitor for high voltage the technique of using inner series-connections in the capacitor elements is an obvious advantage since the number of series-connected capacitor elements can be reduced. The technique is particularly advantageous together with the technique mentioned above for self-healing. Since successful self-healing requires particularly thin metal coating and the currents flowing through the metal generate active power dissipation (heat), thinner layers result in higher losses. One way of reducing the losses without compromising the requirement for a thin metal coating is to choose a shape for the metallized film, and thus a shape for the capacitor element, such that the dimension of the metal coating perpendicular to the rolling direction is decreased and the length of the roll is increased. Unless internal series-connection is used, the consequence of this will be that the cylindrical capacitor elements acquire a relatively little height in relation to their diameter. Series-connecting many such elements, which is required for high voltage, becomes detrimental from the cost point of view. With inner series connections, therefore, several series-connected part-capacitors can automatically be built into a cylindrical capacitor element with an optimal relation between height and diameter, from the manufacturing aspect, and with good self-healing properties.

Capacitor element for a power capacitor, a power capacitor comprising such element and a metallized film for a power capacitor


A writing-utensil packed kit assembly comprises a body pivotally joined to a lid member so as to be openable. The lid member is laid with a mat formed of polyurethane foam, etc., and having a fingertip-inserting hole, the mat including a miniature ruler in its opening. The body includes a miniature eraser received in an end portion cut off by a partition and a suitable number of miniature writing utensils in the other portion. Male and female lid-member stoppers are formed on the peripheral edges of the body and lid member.

This invention relates to a novel kit assembly designed to compactly pack therein writing utensils and so on, esp., those of small size.
Heretofore, there have been available various types of writing-utensil packed kits. However, such existing writing-utensil packed kits have been only designed for writing utensils, etc. of normal sizes. Not until now has there been unavailable such a kit assembly packed with small-sized writing utensils as designed in this invention.


A method of predicting collisions between a mission air vehicle and an airborne object of a plurality of airborne objects present in a flight scenario of the mission air vehicle is described. The mission air vehicle and the airborne object move along corresponding routes. The method acquires data representing the state of flight and flight parameters of the plurality of airborne objects and the mission air vehicle; assigns to each of said airborne objects a mode of calculating the collision prediction; determines a subset of airborne objects to be surveilled; calculates equivalent routes for the mission air vehicle and for each airborne object of the subset; synchronizes the equivalent route of the mission air vehicle with the equivalent route of each airborne object of the subset; and calculates, for each airborne object, a collision prediction based on the synchronized routes according to an assigned calculation mode.

A necessary condition for the flight of unmanned air vehicles (UAVs) on civil flight paths is that they have an equivalent level of safety (ELOS) to that of conventional manned vehicles, in other words that they have collision avoidance systems which can reduce the risk of air-to-air collisions to an equivalent level to that which is found for manned air vehicles.
The access of unmanned air vehicles to non-segregated airspaces is dependent not only on their capacity to detect the presence of an airborne object and manoeuvre autonomously to avoid it, but also on their capacity to interpret data relating to the airspace in which they are located, as a pilot would, in other words to surveil any airborne objects present and to predict sufficiently far in advance any points of impact to be avoided.
Collision prediction systems and methods are known, for example, from EP 1 630 766 (Saab) or WO 2008020889 (Boeing). However, these systems are limited both as to the type of prediction which they can provide, since they make only a short-term prediction, and as to the operating modes which they use to make this prediction.

Method of collision prediction between an air vehicle and an airborne object