A high spatial resolution X-ray computed tomography (CT) system is provided. The system includes a support structure including a gantry mounted to rotate about a vertical axis of rotation. The system further includes a first assembly including an X-ray source mounted on the gantry to rotate therewith for generating a cone X-ray beam and a second assembly including a planar X-ray detector mounted on the gantry to rotate therewith. The detector is spaced from the source on the gantry for enabling a human or other animal body part to be interposed therebetween so as to be scanned by the X-ray beam to obtain a complete CT scan and generating output data representative thereof. The output data is a two-dimensional electronic representation of an area of the detector on which an X-ray beam impinges. A data processor processes the output data to obtain an image of the body part.

1. Field of the Invention
This invention relates to high spatial resolution, X-ray computed tomography (ct) systems.
2. Background Art
The current state of imaging modalities used in these areas of dentomaxillofacial practice, with a particular emphasis on implantology, is described in the following subsections.
Implantology: Pre-operative and Post-operative Imaging
The use of dental implants is becoming an increasingly common treatment to replace missing teeth. Successful outcome of the treatment, osseointegration of the implant, depends heavily on precise presurgical planning. Since the functional load in implants can be high, it is important that the implant be placed in a position where it can contact cortical bone and at an angle where the forces are as perpendicular as possible. Selection of the appropriate size and inclination of the implant in both a bucco-lingual and mesio-distal direction requires precise knowledge of the anatomy of the proposed site, including its dimension in all planes, the presence of knife-edge ridges and undercuts, as well as the location of anatomic structures, such as the nasal fossae, the maxillary sinus, and the mandibular canal. An evaluation of the thickness of the cortical bone and the density of the medullary bone is also important to the success of the implant.
Acquiring the information needed for implant treatment planning requires some type of imaging examination. A number of imaging modalities have been used over the years, but they all have limitations and none are completely satisfactory.
Periapical radiography has enough resolution to depict trabecular bone pattern and the floor of the maxillary sinuses, but the images are limited in size and anatomic coverage and often suffer from geometric distortion. In addition, periapical radiographs are only two-dimensional images and do not provide information about the third, bucco-lingual, dimension.
Panoramic radiography is commonly used for implant site assessment because it is readily available, inexpensive, and provides wide coverage of the jaws. However, there are a large number of disadvantages to this technique that limit its usefulness for implant site assessment. The two primary problems are lack of information in the bucco-lingual plane and variability of the degree of magnification in different parts of the image due to changing distance between the rotational center, jaw structures, and film as the X-ray beam rotates around the head. Minor errors in positioning the patient's head in the machine can also exaggerate the degree of enlargement variability, particularly in the horizontal direction. Although dentists frequently try to overcome these magnification problems by having the patient wear a surgical stent with metal markers of a known size during the examination, this device is not adequate to solve all distortion errors.
Conventional (i.e., non-computed, "focal-plane" or "linear") tomography has found an important application in the presurgical examination of proposed implant sites. Its major advantage over periapical and panoramic radiography stems from its ability to show bucco-lingual cross-sectional images. From these cross-sectional images, the dentist can estimate the spatial relationships of anatomic structures, bone height and width, and the inclination of the alveolar processes at the areas into which the implants are to be placed. Numerous studies have demonstrated that conventional tomography can depict the location of important anatomic structures, such as the mandibular canal, more accurately than panoramic radiography. Dimensional measurements are generally reliable with complex-motion tomography, and less so with linear-motion systems.
Conventional tomographs, however, have been reported not to be of diagnostic quality sufficient to allow identification of the canal in as many as 20% of cases. This is primarily due to the unavoidable blur that is inherent in the method, although some canals are poorly corticated and thus would be difficult to visualize with any technique. Another very important disadvantage of conventional tomography is that it is usually necessary to acquire multiple slices to ensure that the region of diagnostic interest is sampled adequately. Because each slice is acquired successively, the process is time-consuming and laborious, thus expensive, and it exposes the patient to a radiation dose that can be high, depending on the number of slices obtained.
X-ray computed tomography (CT) is a more sophisticated method for obtaining cross-sectional images than conventional tomography. It has been considered to be the most reliable technique for the assessment of bone height and width and localization of the inferior alveolar canal, mental foramen, nasopalatine canal, and maxillary sinuses. Consequently, it has been widely recommended for implant planning.
Conventional CT has its drawbacks, however. First, with its merely 2-D reformatted images, it may not clearly depict the inferior alveolar canal. Second, it is time-consuming: conventional CT requires more than 20 minutes to get all the axial slices for a dental implant study. With such a long scanning time, patient fatigue and patient swallowing start blurring the image. Third, conventional CT exposes the patient to a high radiation dose. Fourth, it is expensive. Fifth, it suffers from poor resolution, especially in the z-direction. Sixth, metal streak artifacts can occur in the presence of metallic dental restorations, requiring judicious selection of scan orientation and boundaries to minimize its occurrence.
Spiral CT is one of the most advanced imaging modalities available and is gradually replacing conventional CT. It is primarily used in the areas of medicine that require full body imaging, but is finding its use in dentistry as well. Spiral CT can generate not only 2-D cross-sectional images, but also fully 3-D images. Its 3-D capability is due to the fact that the X-ray source and detector continuously move along a spiral path relative to the body, thus acquiring data that are essentially 3-D. Spiral CT has been successfully used for the presurgical assessment for implant treatment planning.
However, the use of spiral CT in dentistry is hampered by its high cost and radiation dose, low spatial resolution in axial direction, and metal streak artifacts. In order to overcome some of the disadvantages, specifically high cost and radiation dose, two dental imaging methods have been proposed: Tuned-Aperture Computed Tomography (TACT™) and Ortho-CT.
TACT™, "an inexpensive alternative to CT," is based on the theory of tomosynthesis. The relatively low cost of TACT is party due to its simplicity and partly due to its use of equipment that already exists at the facility. The use of TACT in implantology has been suggested, but no controlled studies have yet been performed. Nevertheless, its disadvantages in implant planning can be assessed from its characteristics. First, TACT requires the use of fiducial markers to estimate the imaging geometry and perform the reconstruction. This adds to the complexity of operating the instrument. Second, it uses CCD sensors of a low contrast resolution. Third, TACT does no have actual 3-D capabilities, but so-called pseudo-3D; 2-D images are being displayed from different angles, simulating varying projection geometries and providing some perception of three dimensions to the viewer. So, with TACT, the gain in cost-effectiveness is offset by a lower quality scan.
Ortho-CT is another potentially inexpensive alternative to spiral CT. Ortho-CT is basically a small cone-beam CT unit obtained by modifying a maxillofacial radiographic unit called Scanora® (Soredex, Helsinki, Finland) in order to acquire a "partial" CT scan.
In this context, the term "partial CT scan" refers to a cone-beam CT scan using a circular orbit, which, in addition to having the usual cone-beam incompleteness problem (i.e., a circular orbit does not satisfy Tuy's completeness conditions), is more incomplete in the sense that the data is insufficient for quantitatively reconstructing 3-D cross-sectional images to the use of a detector and scan geometry that do not measure all necessary rays through the object.
As an example, the "fan-beam scan" or central slice of the circular-orbit cone-beam scan is complete if the detector and scan geometry measure all parallel rays through the object at angles ranging from 0 to 180 degrees.
In the Ortho-CT device, a complete set of parallel rays is not measured at any view angle. It has a good spatial resolution; the resolving power at an MTF of 0.5 can be 1 lp mm−1 and the visual resolution limit about 2.0 lp mm−1. Radiation dose is low; skin dose is almost the same as with panoramic radiography and several dozen times lower than with conventional CT.
However, the applicability of Ortho-CT in implant planning is limited for four reasons. First, it can image only small areas (32×38 mm). If a larger area needs to be imaged, multiple scans are required. Second, its contrast resolution is so low that Ortho-CT is incapable of discriminating soft tissue. Third, its values are only relative and do not correspond to the absolute values of bone density. This is a consequence of its use of incomplete data. Fourth, although its behavior in the presence of metal fillings has not been reported on, it is expected that it suffers from metal streak artifacts.
In addition to presurgical planning of implants, there is a need for long-term maintenance and monitoring of tissue health around the implant after surgery has been performed. Peri-implantitis can progress around dental implants in a manner similar to the progression of periodontitis around natural teeth. If the determination of a failing implant could be made before the implant actually fails, therapeutic intervention might prevent further deterioration of implant support and loss of the implant. A long-standing goal of periodontal research is to find a diagnostic tool with a high sensitivity for detecting subtle disease activity around teeth. In particular, the detection of subtle changes in bone mass may be of great value for evaluating progressive periodontal disease or bone gain/loss after therapy.
Conventional radiography is routinely used by periodontists for the postsurgical assessment of the implant. It can display the mesial and distal aspects of the implant site, but it provides little information about the facial and lingual aspects of the implant site because of the obscuring effects of the radiopaque implant material. Its other major limitations include the subjective interpretation of the radiographic image, lack of sensitivity, and the inability to quantify bone mass.
Digital subtraction radiography can quantify bone mass and thus can be used for postsurgical implant assessment. The method involves taking two separate radiographic scans and then subtracting them. The two images are made at different times and must be as identical as possible. The exposure factors and processing parameters that affect density and contrast must be consistent between the two scans and the projection geometry must be duplicated as nearly as possible All this makes the method laborious and inefficient, especially when the medium is film, which is often the case. Finally, it cannot overcome the obscuring effects of a metal implant sufficiently to allow reliable detection of facial and lingual bone loss at implant sites.
The Temporomandibular Joint (TMJ)
When a patient presents complaints referable to the TMJ region, the findings from the clinical examination may indicate the need for imaging to aid in diagnosis and treatment planning. The osseous structures can be visualized with a variety of imaging techniques, including plain and panoramic radiography, conventional tomography and CT, depending on the degree of detail required.
Conventional tomography plays a significant role in TMJ imaging. Tomographic studies in the lateral and coronal planes demonstrate osseous components of the joint, whereas arthrotomographic examinations provide information about the status of the soft-tissue intra-articular disk. However, tomography of the TMJ is technically demanding because the imaging protocol must be customized for each patient due to the variability of condylar angles. Images made with linear-motion machines may also be suboptimal due to streaking artifacts and incomplete blurring of adjacent structures.
The use of computed tomography for TMJ imaging has generally been reserved for complex cases as a result of its relatively high cost and high radiation dose. Evaluation of articular disk position and function is usually performed with magnetic resonance imaging or arthrotomography, again both expensive techniques.
Detection of Facial Fractures
Another important problem in dentistry is the determination of the location and displacement of facial fractures in patients who have suffered trauma to the maxillofacial region. Complex trauma to the facial skeleton requires both highly qualified clinical knowledge and an accurate imaging technique.
Conventional radiography is unsuitable for the task because it requires multiple scans to obtain all the views that are necessary for evaluation. Even with a series of radiographs, it is sometimes difficult to detect subtle fractures. And conventional tomography, while theoretically capable of demonstrating complex anatomy better than planar projection radiographs, has generally been superseded by CT in most hospitals.
Spiral CT imaging is a better solution for detection of facial fractures. Only one spiral CT scan is needed for the examination, and it does not require movement of the patient to obtain multiple views. It is very fast and can scan the entire midface and the frontal sinus in less than a minute. Thus, it allows the diagnostician to move on to other essential diagnostic and therapeutic interventions without delay. Also, it allows for further processing of the data without requiring the patient's continued presence in the CT unit. Finally, spiral CT produces images of superior quality and can be used to generate 3-D images that can be rotated on a video screen to demonstrate the anatomy and pathology from all angles.
However, the use of spiral CT for detecting facial fractures has drawbacks. It is costly and it exposes the patient to a high radiation dose. It also suffers from metal streak artifacts, which can result in misleading scans of the facial complex.
Lesions and Diseases of Soft Tissue in the Head and Neck
In addition to imaging of the bony structures of the maxillofacial complex, a very important task is the imaging of the soft tissues in the head and neck. Particularly important is imaging of inflammations, cysts, and tumors.
While conventional radiography produces adequate bone images, it provides little information regarding soft tissues as a result of the inability of film-screen systems to record X-ray attenuation differences of less than 2%.
CT, however, is much more effective at separating subtle tissue contrast difference (as low as 0.5%). CT can differentiate not only soft tissue from bone, but also various types of soft tissues from each other. Consequently, CT has found a very important application in the evaluation of the presence and extent of clinically suspected pathology in the head and neck, including tumors, cysts, and inflammations. When additional information concerning the soft tissues is required, an intravenous contrast agent can be used. Cavalcanti et al. have successfully used spiral CT to measure the volume of oral tumors.
Although CT has proven superior in many aspects to other modalities in this application, its use has been limited by three factors: cost, radiation dose and metal streak artifacts. In addition, the spatial resolution available in current CT scanners, which are designed primarily for full-body imaging, may not be optimal for lesions in the head and neck.
MRI has also been used to image soft tissue of the head and neck. Some advantages of MRI over CT include better contrast resolution, absence of artifact degradation from dental restorations, visualization of major vessels without intravenous injection of contrast material, and direct, three-plane imaging without patient repositioning. MRI, however, is more expensive than CT, and requires a longer time to obtain a scan. To date, there is no general consensus about which imaging technique is optimal for use in diagnosis of lesions in the head.
Reconstructive Facial Surgery
Surgery of craniofacial deformities is a complex task that requires careful preoperative planning and specific, detailed information on patient's pathology and anatomy. The goals of maxillofacial surgery are not limited to treating the condition of bone, but extend to improving both the morphology and function of soft tissues, such as facial appearance for the patient. It is necessary, therefore, to ascertain how the proposed alteration of bone will affect the form and function of the surrounding soft tissue. Effective planning of reconstructive facial surgery requires not only adequate imaging of the bone and soft tissue but also the means of interpreting these images in combination to predict how the surgical alteration of bone will affect soft tissue.
Radiography has been used with a certain amount of success for planning facial reconstructive surgery. However, facial reconstructive surgery presents a three-dimensional problem of anatomical rearrangement and cannot be effectively planned using two-dimensional images. Morever, some facial and skeletal anomalies, specifically those involving facial asymmetry, are not amenable to analysis using only two-dimensional images.
CT and MRI can supply detailed, three-dimensional information on the patient's anatomy, and have therefore become the methods of choice in maxillofacial surgery planning. They are typically used in conjunction with computer software that shows the predicted three-dimensional rendered postoperative facial surface. However, both are expensive. In addition, CT suffers from metal streak artifacts and exposes the patient to a high radiation dose while MRI is not particularly useful for examining bony structures.
Several devices have been conceived for dentomaxillofacial imaging. Ortho-CT is a vertically oriented device that acquires a partial CT scan, and while spatial resolution is adequate, the device suffers from artifacts due to the incomplete nature of the scan and does not produce quantitatively accurate estimates of attenuation (necessary for assessing bone quality).
TomCAT is a cone-beam imaging device in which the patient lies supine on an imaging table similar to conventional spiral or single-slice CT instruments. The TomCAT uses an image intensifier and CCD camera for the detector—a combination that has relatively poor dynamic range (reducing quantitative accuracy) and also suffers from spatial distortions. Although images reconstructed from TomCAT have spatial resolution similar to conventional general-purpose CT instruments, contrast resolution is quite poor and images appear to suffer from a great deal of X-ray scatter (and perhaps veiling glare from the image intensifier).
Individual methods are known to be close to the techniques described herein (e.g., Wagner's method for scatter estimation and correction).
The following U.S. patents are deemed to be relevant to the present invention: U.S. Pat. Nos. 5,390,112; 5,615,279; 6,018,563; 5,909,476; 6,118,842; 6,075,836; and 5,999,587. The following U.S. patents are deemed to be of less relevance to the present invention: U.S. Pat. Nos. 5,927,982; 6,094,467; 6,125,193; 5,461,650; 4,812,983; 4,590,558; 4,709,333; 5,243,664; 5,798,924; 6,035,012; 5,293,312; 5,390,112; 5,615,279; 5,644,612; 5,751,785; 5,042,487; and 5,909,476. The following U.S. patents are also deemed to be relevant: U.S. Pat. Nos. 5,778,045; 5,793,838; 5,805,659; 5,815,546; 5,864,146; 5,878,108; 5,881,123; 5,903,008; 5,921,927; 5,949,846; 5,970,112; 5,995,580; 6,052,428; 6,101,234; 6,101,236; 6,104,775; 6,118,841; 6,185,271B1; 6,285,733B1; 6,285,740B1; 6,289,074B1; 6,292,527B1; 6,298,110B1; 6,324,246B1.

High spatial resolution X-ray computed tomography (CT) system

The Regents of the University of Michigan


A medical hand and arm protection apparatus and method of protection comprising a protective shell which is capable of receiving a patient's hand and arm. A sheet is attached to the protective shell, which is tucked under the patient to anchor the hand and arm protector in place. The protective shell also has one or more perforations that allow the medical professional access to the interior of the surgical arm protector to view the patient's IV sites and other medical equipment attached to the patient's hand or arm.

1. Field of the Invention
The present invention relates to medical hand and arm protectors, and in particular to medical hand and arm protectors capable of allowing access to intravenous (IV) sites, and other medical equipment connected to the patient's hand and arm during surgery, medical treatment, and/or recovery.
2. Brief Description of the Related Art
During many types of surgeries and medical procedures, including neurosurgery, cardiac surgery, ear, nose, and throat (ENT) surgery, robotic-performed surgeries, pacemaker procedures, I-port procedures, and other local procedures, the arms of the patient must be tucked to their side. Most commonly, the patient's arm is placed on a piece of foam either on the bed or a sled and taped to another piece of foam that is placed on top of the patient's arm. The draw sheet that the patient is laying on is then pulled over the arm and tucked back underneath the patient to secure their arm.
The inventors have observed that this process of tucking the patient's arms commonly requires up to 15 minutes of valuable time in the operating room. In addition, the inventors have recognized the potential for nerve injuries to the patient's arm, burns to the patient's hands, and the lack of easy access to IV sites using the prior art apparatus and method.
Nerve damage can result either because the arm is pulled too tight, the arm is not resting on a sufficiently padded surface, or because the arm is not positioned anatomically correct during the tucking process. Ulcers from decreased blood circulation can also result when the pressure points of the arm or bony prominences are not padded properly. In addition to during surgery and other medical procedures, nerve damage can also occur in patients that are bedridden, especially when the patients are unable to move their arms.
The inventors also recognize the risk for burns to the patient's hands during surgery. If the patient's finger tips are not properly covered during surgery, the fingers may come in contact with a hot surface, including the bed, the sled, or a cautery that is being used during the surgery.
As described above and in U.S. Pat. No. 5,546,963 to Doody, surgical arm protectors are known in the art. However, the prior art arm protectors do not allow adequate access to the patient's IV sites, and other medical instruments connected to the patient's arm or hand during surgery, medical treatment, and/or recovery. Specifically, all patients have at least one IV connected to their hand or arm ranging from the antecubital region of the arm, forearm, wrist, and/or back of the hand. In addition, in some cases, patients require an arterial line which is usually placed in the wrist to draw blood to monitor the patient's blood pressure and blood oxygen level. In order to draw blood from this line, the anesthesiologist must have free access to this line. However, with the prior art apparatus and method of tucking, the anesthesiologist is frequently required to get under the sheet to reposition and re-tuck the arm because the arterial line is extremely sensitive. The pressure from tight tucking causes movement and sometimes loss of the line. In addition, the arterial line and the other IV lines can get caught in the frame of the bed and the other appliances clamped to the bed during surgery if they are not properly stowed and secured. Easy IV site access is even more challenging in robotic surgeries where the patient is placed in a sharp trendelenberg position.
It would therefore be desirable to develop a medical hand and arm protector that is capable of providing support and protection of the arm during surgery, medical treatment, and/or recovery, while also allowing the medical professional access to IV sites and other medical equipment that is connected to the patient's hand and arm.

This patent is subject to a terminal disclaimer.

Medical hand and arm protection apparatus and method of protection

Board of Trustees of the University of Arkansas


An electrical potential difference between a slider body and a hard disk of a hard disk drive is eliminated based on the flying-height spacing of the slider body between the slider body and the hard disk. A predetermined bias voltage is applied between the slider body and the hard disk that includes a DC component and an AC component and that is based on the detected flying-height spacing of the slider body. The flying-height spacing can be detected based a minimum slider-to-disk clearance change from a design flying height of the slider at a frequency of the AC component as the DC component of the predetermined bias voltage is varied. Alternatively, the flying-height spacing can be detected based on a minimum electrodynamic response of the slider to a first harmonic of the AC frequency of the AC component as the DC component is varied.

1. Field of the Invention
The present invention relates to hard disk drives (HDDs). More particularly, the present invention relates to a technique for detecting and eliminating an electrical potential difference between a slider body and a disk surface of an HDD, such as a contact potential caused by material differences between the slider and the disk or a potential generated by tribocharging.
2. Description of the Related Art
FIG. 1 shows an exemplary hard disk drive (HDD) 100 having a dual-stage servo system for positioning a slider assembly 101 over a selected concentric data information track on a magnetic disk 102 for writing data to and/or reading data from the selected track. The dual-stage servo system of HDD 100 includes a primary actuator 104, such as a rotary voice-coil motor (VCM), for coarse positioning an actuator arm 105 and a read/write head suspension 106, and a secondary actuator (not shown in FIG. 1), such as a microactuator or micropositioner, for fine positioning slider assembly 101 over a selected track. A microactuator, as used herein, is a small actuator that is placed between a suspension and a slider and moves the slider relative to the suspension. Slider assembly 101 includes a read/write head (not shown in FIG. 1) having a read element, such as a Giant Magnetoresistive (GMR) element, and a write element that respectively read data from and write data to a selected data track. While HDD 100 is shown as having only a single magnetic disk 102, HDDs typically have a plurality of stacked, commonly rotated, rigid magnetic disks and a corresponding number of actuator arms, read/write head suspensions, secondary actuators and slider assemblies.
As slider-to-disk spacing becomes smaller than 10 nm, electrostatic and intermolecular forces between a slider and a disk become increasingly significant. Even when a slider body and a disk are both grounded, a potential difference can exist between the slider body and the disk that can generate an electrostatic force greater than the van der Waals force. One source of the potential difference is tribocharging, or frictional electrification of non-conducting materials on the slider body. (See, for example, J. D. Kiely et al., "Tribocharging of the magnetic hard disk drive head-disk interface," Journal of Applied Physics, Vol. 91, No. 7, pp. 4631–4636, Apr. 1, 2002.) Another source is the contact potential between the conducting materials of the slider body and the disk.
FIG. 2 depicts an electrostatic field that can exist between a slider body 201 and a hard disk 202 of a hard disk drive. A suspension supporting slider body 201 is not shown. As disk 202 rotates, disk 202 moves from right to left with respect to slider body 201, as indicated by arrow 203. Enlargement 204 of the slider-disk interface shows lines representing an electric field 205 that is formed from a potential difference between slider body 201 and disk 202. Electric field 205 exists between slider body 201 and disk 202 all along the length of slider body 202, but is only indicated in enlargement 204 because the intensity of electric field 205 is greatest at the trailing edge of slider body 201. As mentioned, one source for the potential difference is the contact potential that originates from the conducting portions of the slider body and disk having different work functions and from tribocharging of the non-conducting portions. Another source for the potential difference is tribocharging associated with the spindle motor bearing, which can shift the disk potential significantly from ground potential.
Electric field 205 between slider body 201 and disk 202 generates an electrostatic force that acts the on the surfaces of slider body 201 and disk 202 within the slider-disk interface. The electrostatic force associated with electric field 205 depends on the applied voltage and the other physical parameters of the slider-disk interface. As the potential difference between the slider body and the disk increases, the slider flying height is reduced from the design flying height of the slider.
For example, FIG. 3 shows the flying height (FH) for a high-pitch air bearing design and a low-pitch air bearing design as a function slider-disk potential difference. Both air bearing designs have a design fly height 9 nm above a disk. The high-pitch slider has a dynamic pitch angle of 180 μrad. The low-pitch slider has a dynamic pitch angle of 70 μrad at a flying height of 9 nm. Curve 301 represents the flying height for the high-pitch slider as a function of the slider-disk potential difference. Curve 302 is the flying height for a low-pitch slider as a function of the slider-disk potential difference. The low-pitch slider is more sensitive to an applied DC electric field than a high-pitch slider because a low pitch design has on average a smaller separation distance than a high-pitch design when the electrostatic force is integrated over the slider. The flying height is reduced by about 0.5 nm for a potential difference of about 0.5 V for both the high-pitch and low-pitch air bearing designs. The value of the flying height at 2.5 V for the low-pitch slider is extrapolated to 0 nm because contact occurs at 2.5 V.
In current hard drives, the disks are lubricated using perfluoropolyether-type lubricants having long polar chains, such as Fomblin Z-DOL. The polarity of the lubricant in the presence of an electrostatic field at the head-disk interface can cause lubricant to be removed from the disk surface and possibly be depleted from the disk surface. The removed lubricant is usually picked up by the slider and can lead to drive failure. Consequently, as lubricant is removed, the lubricant is attracted to slider body 201 by the polarity of the lubricant and the electrostatic force and becomes concentrated in areas on slider body 201 that have a high electric field, such as the trailing edge of the slider body. Once concentrated, the lubricant can form droplets that can lead to read/write errors when the droplets of lubricant enter the head-disk interface. Electric field 205 can also attract particles onto slider body 201 that can lead to scratches on both slider body 201 and the surface of disk 202. Yet another potential problem that is caused by the electrostatic force is an increased vibrational coupling between slider body 201 and disk 202, leading to larger modulations of the slider-disk spacing.
A number of researchers have found over the past years that slider-to-disk spacing can be controlled by adjusting a DC bias applied to the slider-disk interface. See, for example, U.S. Pat. No. 6,005,736 to E. T. Schreck; U.S. Pat. No. 6,529,342 to Z. Feng et al.; and U.S. Pat. No. 6,366,416 B1 to D. W. Meyer et al.
Accordingly, what is needed is a technique for determining the optimum bias voltage that should be applied between a slider body and a disk for eliminating an electrical potential difference that exists between the slider body and the disk, such as a contact potential.

Method for actively controlling electric potential at the head/disk interface of a magnetic recording disk drive

Hitachi Global Storage Technologies Netherlands B.V.


The present invention discloses a surface orientation sensing structure, where six printed circuit boards are combined to form a regular hexahedron as the axis of an intelligent magic cube, and a main control chipset can recognize layer rotation by simply sweeping a copper foil through a brush sheet to cause a level change, so that the position change of the layer can be recognized more accurately, a step loss rate is reduced, parts are reduced, and the assembly process is simplified. The present invention further discloses an intelligent magic cube, where all the parts related to orientation sensing are concentrated on the axis, so that the intelligent magic cube can be operated more easily and smoothly, the intelligent functions of the intelligent magic cube can be used more smoothly, and user experience is improved.

A magic cube is a very popular intellectual toy that has a simple structure and is changeable. A conventional third-order cube is composed of one central shaft, six central blocks connected to the central shaft, 12 edge blocks embedded between every two central blocks, and eight corner blocks embedded among every three edge blocks.
The conventional third-order magic cube has the following disadvantages:                (1) The magic cube is changeable; and it is difficult to solve the magic cube without knowing the complicated formulas, which cannot be easily remembered.        (2) It is difficult to time accurately. In current magic cube solving competitions, players need to press the button to stop the timer after the cube is solved, so there will always be a timing error of about 0.5 seconds.        (3) It is inconvenient for the players to perform technical communication with each other. Because of hand occlusion during the solving operation, it is difficult for bystanders or cameras to observe the complete operation process. In addition, it is difficult to record the solving steps.
To resolve the above-mentioned technical problems, the prior art provides an intelligent magic cube with reminding and recording functions, which is disclosed in WO/2016/173476. However, the intelligent magic cube has the following disadvantages:                (1) There are many electronic accessories and plastic parts, therefore the magic cube is heavy, and the players cannot operate the magic cube quickly.        (2) The assembly process is complex, resulting in a high manufacturing cost and inconvenience for the user to disassemble and debug.        (3) Due to excessive layout of parts related to surface orientation sensing, sensing errors are easy to occur, which results in main control judgment errors in the intelligent magic cube and affects the user experience.        (4) A surface orientation sensor of the intelligent magic cube, that is, a physical detection module circuit in the prior art, is generally installed in a central block, and consequently, the user cannot adjust the axis and the floating amplitude of the intelligent magic cube by using the axis floating elasticity adjustment system disclosed in the prior application CN210384805U.        (5) Various sensors and surface orientation detection mechanisms of the intelligent magic cube use wire welding and FPC flat wire welding, therefore the welding cost is high, the wire layout is disordered, and the intelligent magic cube cannot be normally used due to the fact that poor welding and wire breakage are easy to occur in long-term use.

Surface orientation sensing structure and intelligent magic cube

GUANGZHOU GANYUAN INTELLIGENT TECHNOLOGY CO., LTD.


A two-cycle internal combustion engine provided with at least one fuel injection nozzle, wherein the fuel injection nozzle is provided with a heating element for heating the fuel so as to cause the fuel to undergo a phase change before the fuel is injected from the fuel injection nozzle. A fuel control circuit for controlling the heating element is attached to the engine so that an AC electromotive force generated at a generator portion of an ignition device is input therein and, based on such electromotive force, the heating element is controlled. All of the ignition device, the fuel controlling circuit and the generator portion are formed into a single integrated body which functions as an ignition/fuel controlling device.

1. Field of the Invention
This invention relates to a two-cycle internal combustion engine of the fuel injection type, and in particular to a two-cycle internal combustion engine of the fuel injection type which is relatively small in size and suited for use in a portable working machine such as a chain saw or a bush cutter.
2. The Prior Art
Because of the increasing concern in recent years of environmental problems, a reduction not only of the toxic substances in the exhaust gas but also of the engine noise is strongly demanded even in a small two-cycle internal combustion engine. In particular, there are pollution problems inherent to a two-cycle internal combustion engine, i.e. a problem of how to reduce the quantity of HC in the exhaust gas which is brought about due to a phenomenon of blow-by of unburnt air-fuel mixture from a combustion chamber, and a problem of how to prevent the discharge of unburnt fuel which is brought about due to a phenomenon of spitting of fuel toward the air-cleaner. These problems are also desired to be solved.
On the other hand, a lean burn engine, or a direct injection engine wherein fuel is directly injected into a combustion chamber has been recently proposed as a four-cycle internal combustion engine. In these types of engine, the reduction of toxic substances in the exhaust gas by means of a lean-burning technique is taken into consideration. Therefore, it is now studied how to apply this technique to a two-cycle internal combustion engine.
For example, a two-cycle internal combustion engine of the direct fuel injection type is proposed in U.S. Pat. No. 4,813,391. According to this technique, a fuel injection nozzle is disposed at a cylinder head portion of the combustion chamber so as to permit the injection of fuel to be effected directly into the combustion chamber. In this case, a fuel pump is actuated taking advantage of the fluctuation in pressure within a crank case, and, through this actuation of the fuel pump, fuel is fed to the fuel injection nozzle and then directly injected into the combustion chamber. The stroke of fuel injection, i.e. the injection of fuel from the injection nozzle, is performed as follows. Namely, as a piston is moved downward, the pressure inside a crank-case is proportionally increased, and when the piston is brought down to approximately the bottom dead center, the fuel pump is actuated by the pressure inside the crank-case, thus feeding fuel to the fuel injection nozzle, from which the fuel is injected by the pressing force of the fuel pump into the combustion chamber.
There is also known another example of a two-cycle internal combustion engine of the direct fuel injection type, wherein a fuel injection nozzle is disposed midway of an air passage (scavenging passage) communicating with a combustion chamber. Fuel from the injection nozzle is injected toward a heat conductive wall constituting a cylinder wall and impinged thereon so as to be gasified and mixed with air passing through the air passage, the resultant air-fuel mixture being fed to a combustion chamber (U.S. Pat. No. 4,876,999).
However, in the case of the former engine of the direct fuel injection type (U.S. Pat. No. 4,813,391), wherein the fuel injection nozzle is mounted on a cylinder body and fuel is directly injected from the fuel injection nozzle into the combustion chamber, the timing and manner of fuel injection are set such that the fuel pump is actuated depending on the pressure change inside the crank-case and the fuel is injected by the delivery pressure of the fuel pump, so that the timing of fuel injection as well as the quantity of fuel to be injected are rather difficult to adjust. At the same time, a fuel pump for injection of fuel as well as an operation system for actuating the fuel pump are required to be employed. Therefore, this fuel injection mechanism is not suited for the combustion control (air/fuel ratio control) of the engine and the structure thereof is rather complicated, thus raising a problem that the manufacturing cost thereof would be increased.
On the other hand, in the case of the injection system of a fuel injection nozzle which is commonly employed in a four-cycle internal combustion engine, fuel is compressed by means of a plunger pump and then fed to the fuel injection nozzle. An electrically operable member such as an electromagnetic solenoid is mounted on the fuel injection nozzle. On the occasion of fuel injection, the electrically operable member is magnetized to open or close the valve of the fuel injection nozzle.
In this fuel injection system, the timing of fuel injection is controlled electrically, thus making it possible to inject fuel at an appropriate timing and to adjust the quantity of fuel. However, it is required according to this system to provide the fuel injection nozzle with an electrically operable member and a nozzle shut-off valve, and at the same time to install a control device for controlling the fuel injection nozzle. These devices which are required in the manufacture of the fuel injection type engine as mentioned above are rather expensive, so that the application of the fuel injection nozzle of this system to a two-cycle internal combustion engine for a bush cutter, etc. is not suitable in terms of cost.


This weak signal detection system has: a statistical data acquisition unit which measures the average value or distribution of an input signal in which is noise superimposed on a desired signal, calculates parameters such as the amplitude or noise dispersion of the desired signal, and outputs the calculated data obtained thereby; a nonlinear characteristic unit which outputs a signal having a nonlinear response with respect to the magnitude of the voltage or the current of the input signal; a signal detection ratio evaluation unit which determines whether the output signal from the nonlinear characteristic unit is the desired signal, calculates the detection ratio in the event that the signal is the desired signal, and outputs detection ratio data; a parameter adjustment unit which, on the basis of detection ratio data obtained by the signal detection ratio evaluation unit and calculated data obtained by the statistical data acquisition unit, adjusts a control parameter pertaining to the responsiveness of the nonlinear characteristic unit; and a signal processing unit which performs signal processing of the output signal of the nonlinear characteristic unit, and conversion to digital data or image data. In so doing, it is possible to provide a weak signal detection system having improved signal detection accuracy, and an electron microscope equipped with the system.

In recent years, in a semiconductor inspection device, medical diagnosis/measurement instrument, or the like, as an inspection object is miniaturized, a signal to noise ratio (Signal to Noise Ratio: SNR) decreases in a detection signal that inspects and measures the object. It is required that a desired signal on which a shape, physicality, and the like of the inspection object are reflected is detected with high accuracy from such a detection signal of a low SNR. For example, a semiconductor inspection/measurement device is a device that irradiates laser, light, an electron beam, or the like onto a wafer being an inspection/measurement object, converts scattered light or a secondary electron from the wafer into an electrical signal by a detector such as photomultiplier or a scintillator, and inspects and measures shapes of foreign objects or patterns on the wafer through a preamplifier, a signal processing circuit, or a display.
In the semiconductor inspection/measurement device, along with the refinement of semiconductors, amount of laser, light, or an electron beam is narrowed down to thereby improve measurement resolving power. On the other hand, by narrowing down the dose, intensity of the desired signal becomes small relatively as compared to noise generated in a detector, an amplifier, or the like, and therefore it is difficult to detect the desired signal with high accuracy.
Therefore, a method is used, for example, by using randomness of noise, averaging detection signals, and detecting the desired signal with high accuracy. JP-A-2008-286736 (Patent Literature 1) describes, for example, "a signal that responds to amplitude of voltage or current of a certain input signal is set to a detection target. In a multichannel weak signal detection system that detects a plurality of response signals changing in time particularly, an input signal is time-division-multiplexed, conditions of multiplexing are optimized, and averaging-processing in two stages is performed with respect to the response signal, and thereby a weak signal is detected at a high SN ratio".
Further, as a method for improving a signal detection ratio of an input signal with high intensity noise, a technique disclosed in JP-A-2002-221546 (Patent Literature 2) is used. Patent Literature 2 describes "an input signal is input to a nonlinear circuit 11, its output time series is memorized (13), and its power spectrum is calculated (15). Further, noise is generated (16), its intensity is raised gradually, synthesized with the input signal after raising its intensity gradually, and provided to the nonlinear circuit 11. The power spectrum is calculated in each noise intensity, a peak of each power spectrum is detected (18), and its peak value is acquired. Further, a maximum peak value is acquired and used as a period of a weak signal for acquiring the period of the maximum peak (20)".

Weak signal detection system and electron microscope equipped with same


A transformer includes a primary winding coil, a plurality of electrically-conductive sheets, a bobbin and a magnetic core assembly. The bobbin includes a first tube member, a second tube member and plural partition plates. The first tube member and the second tube member have a first channel and a second channel therein, respectively. Each partition plate is sheathed around the first tube member and the second tube member and includes a receptacle for accommodating respective electrically-conductive sheet, and the primary winding coil is wound around the second tube member.

A transformer has become an essential electronic component for various kinds of electric appliance. Referring to FIG. 1, a schematic exploded view of a conventional transformer is illustrated. The transformer 1 principally comprises a magnetic core assembly 11, a bobbin 12, a primary winding coil 13 and a secondary winding coil 14. The primary winding coil 13 and the secondary winding coil 14 are wounded around the bobbin 12. A tape 15 is provided for isolation and insulation. The middle portions 111 of the core 11 are embedded into the cylinder tube 121 of the bobbin 12. The primary winding coil 13 and the secondary winding coil 14 interact with the magnetic core assembly 11 to achieve the purpose of voltage regulation.
Since the leakage inductance of the transformer has an influence on the electric conversion efficiency of a power converter, it is very important to control leakage inductance. Related technologies were developed to increase coupling coefficient and reduce leakage inductance of the transformer so as to reduce power loss upon voltage regulation. In the transformer of FIG. 1, the primary winding coil 13 and the secondary winding coil 14 are superimposed with each other and wounded around the bobbin 12. As a consequence, there is less magnetic flux leakage generated from the primary winding coil 13 and the secondary winding coil 14. Under this circumstance, sine the coupling coefficient is increased, the leakage inductance of the transformer is reduced and the power loss upon voltage regulation is reduced, the electric conversion efficiency of a power converter is enhanced.
In the power supply system of the electric products in the new generation, for example LCD televisions, the transformer with leakage inductance prevails. The current generated from the power supply system will pass through a LC resonant circuit composed of an inductor L and a capacitor C. The inductor L is provided from the primary winding coil of the transformer. Meanwhile, the current with a near half-sine waveform will pass through a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor) switch. When the current is zero, the power MOSFET switch is conducted. After a half-sine wave is past and the current returns zero, the switch is shut off. As known, this soft switch of the resonant circuit may reduce damage possibility of the switch and minimize the noise.
In order to increase the leakage inductance of the transformer, the primary winding coil should be separate from the secondary winding coil by a certain distance to reduce the coupling coefficient of the transformer. Referring to FIG. 2, a schematic exploded view of a transformer with leakage inductance according to prior art is illustrated. The transformer 2 principally comprises a bobbin 21, a primary winding coil 22, a secondary winding coil 23 and a tape 24. The bobbin 21 comprises a first side plate 211, a second side plate 212 and a winding member 213. The tape 24 is wound around the middle portion of the winding member 213 and has a width d. The winding member 213 is divided into a first winding section 2131 and a second winding section 2132, which are located at bilateral sides of the tape 24. The primary winding coil 22 and the secondary winding coil 23 are wound around the first winding section 2131 and the second winding section 2132, respectively. The first winding section 2131 is separated from the first side plate 211 by wrapping a first side tape 25 on the winding member 213 between the first winding section 2131 and the first side plate 211. Likewise, the second winding section 2132 is separated from the second side plate 212 by wrapping a second side tape 26 on the winding member 213 between the second winding section 2132 and the second side plate 212. For safety regulations, the tape 24 is used for isolation between the primary winding coil 22 and the secondary winding coil 23. Via the first side tape 25 and the second side tape 26, the primary winding coil 22 and the secondary winding coil 23 are electrically isolated from the conductors outside the transformer 2. As the width d of the tape 24 between the primary winding coil 22 and the secondary winding coil 23 is increased, the coupling coefficient is reduced and the leakage inductance of the transformer is increased. Under this circumstance, the resonant circuit of the power supply system will be conveniently controlled.
Although the transformer structure of FIG. 2 is advantageous for increasing the leakage inductance, some drawbacks still exist. As previously described, the magnitude of the leakage inductance is dependent on the width d of the tape 24 between the primary winding coil 22 and the secondary winding coil 23. Since the tape 24 is made of flexible material and fails to be firmly fixed, the structure of the transformer is readily distorted due to a long-term using period or serious vibration. Under this circumstance, the magnitude of the leakage inductance is reduced or unstable, and the resonant circuit of the power supply system will be adversely affected. Since these tapes are sticky and narrow in width, the procedures of wrapping the tape 24, the first side tape 25 and the second side tape 26 are labor-intensive and complicated. In addition, if the wrapping result is unsatisfied, the electrical performance of the transformer is impaired.
Since the tape 24, the first side tape 25 and the second side tape 26 are wrapped on the winding member 213 of the bobbin 21, the remaining area or volume for winding the primary winding coil 22 and the secondary winding coil 23 around the winding member 213 is limited and thus the heat-dissipating effect is usually insufficient. Furthermore, after the procedures of winding the coils and wrapping the tapes, a layer of insulating tape is additionally wrapped around the primary winding coil 22 and the secondary winding coil 23. The insulating tape also impairs heat dissipation of the transformer during operation. Moreover, since the melting point of the tape 24 is relatively lower, the operating temperature of the transformer is restricted by the melting point of the tape 24.
Furthermore, since the secondary winding coil of the conventional transformer is manually wound and fabricated, the labor cost is increased and the fabricating efficiency is reduced. The diameter of the secondary winding coil is too small to be used in high power application.
In views of the above-described disadvantages, the applicant keeps on carving unflaggingly to develop a structure of a transformer according to the present invention through wholehearted experience and research.


An agricultural bagging machine is disclosed which includes a plurality of horizontally disposed and vertically spaced cables positioned at the rearward end of the tunnel of the machine. The cables are dragged through the silage being bagged as the bagging machine moves away from the closed end of the bag so that the proper amount of density is created in the material being bagged. Each of the cables defines a cable loop which extends rearwardly from the output end of the tunnel into the open end of the bag. The lengths of the cables may be adjusted to permit the density to be controlled. The number of cables may also be varied to control the density in various types of silage materials.

1. Field of the Invention
This invention relates to an agricultural feed bagging machine and more particularly to an agricultural feed bagging machine having means associated therewith to control the density of the material being packed in the bag without the need for a backstop and cable brakes.
2. Background Information
Agricultural feed bagging machines have been employed for several years to pack or bag silage or the like into elongated plastic bags. Two of the earliest bagging machines are disclosed in U.S. Pat. Nos. 3,687,061 and 4,046,068. In the prior art bagging machines, silage or the like is supplied to the forward or intake end of the bagging machine and is fed to a rotor which conveys the silage into a tunnel on which the bag is positioned so that the bag is filled. As silage is loaded into the bag, the bagging machine moves away from the filled end of the bag in a controlled fashion so as to achieve uniform compaction of the silage material within the bag. In U.S. Pat. No. 4,337,805, silage is forced by means of a rotor from the intake chamber of the machine through the output chamber of the machine and into the agricultural bag with a backstop structure yieldably engaging the closed end of the agricultural bag to resist the movement of the bagging machine away from the filled end of the agricultural bag as silage is forced into the bag. The structure of the '805 patent includes a pair of drums rotatably mounted on the bagging machine with a brake associated therewith for braking or resisting the rotation of the drum with a selected brake force. A cable is wrapped around the drum and is connected to the backstop.
Although the cable drum and backstop structure of the '805 patent and other similar machines do function generally satisfactorily, the cables, which are positioned on opposite sides of the bag, can create openings or holes in the bag which will adversely effect the fermentation process within the bag. A further disadvantage of the cable drum and backstop structure of the devices such as shown in the '805 patent is that the cables must be rewound after the filling of an individual bag. A further disadvantage of the cable drum and backstop structure of the machine such as disposed in the '805 patent is that a dangerous condition exists should one of the cables break.
In an effort to overcome some of the disadvantages of machines such as disclosed in the '805 patent, an attempt was made in U.S. Pat. No. 4,621,666 to achieve the desired bagging operation while eliminating the need for the cable drum and backstop structure. In the '666 patent, the wheels on the bagging machine were braked to provide the desired resistance to the filling of the bag. Although the brake system of the '666 patent apparently met with some success, it is believed that machines such as disclosed in the '666 patent experience slippage difficulties in wet field conditions which adversely effect the bagging operation. It is also believed that the brake means alone on the bagging machine such as those disclosed in the '666 patent do not achieve the desired compaction of the silage material within the bag.
In applicant's co-pending application, a bagging machine is described which has the capability of enabling the density of the silage material to be selectively controlled without the need of an elaborate braking system. Although the bagging machine of the co-pending application does satisfactorily achieve all of its objectives, a more simple way of controlling the density of the bagged material has been discovered and is believed to represent a significant advance in the prior art and a significant advance over the bagging machine of the co-pending application.

Density control means for an agricultural feed bagging machine


A water pump disconnect clutch including: a first race having first and second portions with first and second diameters, respectively; a second race having at least one ramp; at least one rolling element disposed radially between the first and second races; and an engagement means for axially displacing the at least one rolling element. In response to an increase in temperature for the pump above a specified level, the engagement means is for axially displacing the at least one rolling element from a first position, in which the first and second races are rotationally independent, to a second position to rotationally lock the first and second races. In response to a decrease in temperature for the pump below the specified level, the engagement means is for axially displacing the at least one rolling element from the second position to the first position.

It is desirable to disconnect unnecessary devices from an automobile engine when not needed to avoid parasitic drag. For instance, it is common to disconnect air conditioner compressors and cooling fans. Similarly, disconnection of an engine water pump when the engine is cool improves fuel economy and reduces the time necessary for the engine to reach optimal operating temperature.
It is known to use electrical devices to control water pumps. U.S. Pat. No. 6,915,887 describes an electromagnetic type clutch for disconnecting a water pump. At least one manufacturer is producing an electric driven water pump. However, use of electronic devices and controls introduces cost and complexity.
It is known to use thermostatic devices to couple and release relatively rotatable members. U.S. Pat. No. 2,570,515 describes a device for an automobile radiator fan in which jamming rollers with camming projections are engaged with a thermostat to couple and uncouple the driving and driven members. However, once engaged, it is difficult to disengage the jamming roller clutch by applying the minimal force from the thermostat to the projections.
U.S. Pat. No. 6,619,454 describes a disconnect device in which balls are held in place by a keeper that moves axially to release the balls and disconnect the drive. Such a device is designed to disconnect in the event of a malfunction. It is difficult to reconnect the input and output elements under load due to large contact angles and high friction.
Thus there is a long-felt need for a water pump disconnect clutch with low cost and complexity. There is also a need for a water pump disconnect clutch with low engagement friction that can be easily engaged and disengaged with a thermostatic device.


The invention discloses a wheel structure and a scooter comprising the wheel structure. The wheel structure comprises: an inner rim having a first inner annular face and a first outer annular face that are arranged radially, the first inner annular face is hollow and provided with an interface for connecting to a steering mechanism of the scooter; an outer rim having a second inner annular face which is arranged radially and a second outer annular face for contacting the ground; wherein an intermediate connecting assembly is disposed between the first outer annular face of the inner rim and the second inner annular face of the outer rim, and the outer rim, without need for hub, contacts the inner rim in a rolling manner via the intermediate connecting assembly and is rotatable relative to the inner rim. The wheel structure does not contain a hub and presents a hollow visual effect of the wheel.

Sport entertainment apparatus are being developed continuously. As a modern entertainment apparatus, the scooter has gradually entered individual families. The scooter can be either used as novel means of transportation, or as an entertainment apparatus, which therefore brings about a lot of convenience and happiness to people's lives. Therefore, the scooter has become very popular among people, especially the youth.
The steering mechanism of a scooter is typically disposed at a front end of the body. When performing a steering operation, the pedal is inclined to generate a steering torque, which is transmitted by the steering mechanism, eventually realizing turning of the front wheels. As is well known, the structure of a prior art wheel comprises at least an outer wheel, a hub and an inner wheel, wherein the outer wheel contacts the ground, the inner wheel is connected to the steering structure, and the hub is located between the outer wheel and the inner wheel. The prior art wheel is complicated in structure and has numerous parts and components, thus requiring complex steps of assembly and consuming time.

Shanghai Magic Wheels Sporting Goods Co., Ltd.


A transmission includes a ring gear driven by a first primary gear train, a carrier driven by a second primary gear train and a sun gear driven by a third primary gear train. Clutches are utilized to lock and unlock the ring gear, carrier and sun gear. When locked each rotate at the same speed and the torques are added together at an output shaft to provide a high torque low speed output from the transmission. As the transmission accelerates the clutches are disengaged allowing the ring gear, carrier and sun gear to rotate separately and achieve higher speeds, providing a continuous output from high torque to high speed operation.

The invention generally relates to a transmission providing an uninterrupted transition from high torque to high speed operation.
Transmissions commonly operate in both high torque, low speed and low torque, high speed situations. At start up of an associated vehicle the transmission is moving at low speeds with a higher torque output required by the vehicle. As the speed of the vehicle and transmission increases lower torque output from the transmission is required. Typically, when transferring from high torque to high speed operation the transmission requires at least one shift to change the gear ratios. Each time a gear shift occurs the output of power from the transmission is momentarily interrupted.
To reduce the number of such power interruptions, continuously variable transmissions have been utilized. Continuously variable transmissions employ electric motors to provide input to the transmission at low speeds. Use of the electric motor provides a greater range of operating speed for the transmission before a gear shift is required. However, while greater ranges of transmission speeds are available, known designs are limited in the amount of torque available at the output of the transmission. Thus, using continuously variable transmission in applications requiring high torque is not always practical.
An improved arrangement for providing a continuously variable transmission which allows an uninterrupted transition from high torque to high speed is needed.

Continuously variable constant mesh epicyclic transmission


A method for manufacturing a film, notably monocrystalline, on a flexible sheet, comprises the following steps: providing a donor substrate, forming an embrittlement zone in the donor substrate so as to delimit the film, forming the flexible sheet by deposition over the surface of the film, and detaching the donor substrate along the embrittlement zone so as to transfer the film onto the flexible sheet.

The formation of a film, notably monocrystalline, on a flexible sheet is not easy to accomplish.
Indeed, the flexible sheets of interest do not in general have a seed surface suited to the growth of a film of good crystalline quality.
Furthermore, techniques of bonding a film on a flexible sheet are also difficult to implement, because the surfaces to be placed in contact may not be sufficiently smooth to enable direct bonding. On the other hand, the flexibility of the sheet makes good application against the film difficult.
Furthermore, numerous adhesives would be unsuitable in view of their too high rigidity in view of the application. These adhesives may also prove to be unsuitable in view of their incompatibility with the heat treatments that can be necessary for shaping the monocrystalline film.

Method for manufacturing a film on a flexible sheet


A medicament for the preventive and/or therapeutic treatment of allergic diseases and/or endometriosis and/or hysteromyoma which comprises as an active ingredient a substance selected from the group consisting of a compound represented by the following general formula (I) and a pharmacologically acceptable salt thereof, and a hydrate thereof and a solvate thereof:

Allergic diseases are understood to be caused by production of IgE by an antigen stimulation invaded in a body, and successive release of various chemical mediators such as inflammatory cytokine, histamine, leukotriene and the like by a degranulation from an activated mast cell stimulated by a complex of the antigen and IgE, thereby constriction of airway, accentuation of vascular permeability, inflammation of skin, bronchi and the like are induced. Accordingly, antiallergic agents are understood mainly as drugs inhibiting allergic reaction type I and successively induced allergic inflammation, particularly as drugs inhibiting the production and release of the mediators from mast cells, or those as being antagonists against the aforementioned actions. At present, steroids, antihistaminic drugs, suppressants or inhibitors of the release of mediators and the like have been used as antiallergic agents. Although steroids are very effective drugs, they have a problem of side effects. Antihistaminic drugs are only for symptomatic therapies and fail to achieve radical therapy. Suppressants or inhibitors of the release of mediators are considered to have a high effectiveness. However, some of them lack immediate effectiveness or have central side effects. Accordingly, the antiallergic drugs currently available are not fully satisfactory as they are.
Patients with endometriosis are increasing in recent years, and currently, 10 to 14% of females are considered to be suffered from the disease. Endometriosis has been focused as a cause of sterility, as well as the disease lowers the quality of life of patients with severe pains during menstruation and coitus. For a treatment of the disease, a therapy by using a hormone drug has been currently applied as a pseudo menopausal therapy. However, the aforementioned therapy induces strong side effects, and it also has a risk of causing osteoporosis during a long-term administration. Therefore, at present, a drug or a method for treatment with safety and high efficacy is not available.
In recent years, it was found that mast cells exist apparently with high density in the lesion of endometriosis (American Journal of Reproductive Immunology (New York: 1998), (Denmark), Vol. 40, No. 4, p. 291-294), and that mast cells are activated to lead degranulation (Nikkei Medical, 2002, No. 415, p. 28; Fertility and Sterility, (USA), 2002, Vol. 78, No. 4, p. 782-786). Furthermore, a relation between endometriosis and allergy is strongly suggested, because interstitial hyperplasia, which is a major step of infiltration and lesion of mast cells, is significantly inhibited by the administration of a leukotriene antagonist having antiallergic action to an endometriosis model rat (Nikkei Medical, 2002, No. 415, p. 28; Fertility and Sterility, (USA), 2002, Vol. 78, No. 4, p. 782-786).
Therefore, an antiallergic drug, which strongly inhibits activation of mast cells and can be used as a therapeutic agent for radical treatment of allergic diseases, is usable as an effective therapeutic agent for endometriosis.
45% of patients with endometriosis are suffered from hysteromyoma, which suggests a relation of hysteromyoma and allergy in the same manner as endometriosis. Accordingly, it is highly probable that an antiallergic agent, which can be used as a therapeutic agent for radical treatment of allergic diseases, is useful as a therapeutic agent for hysteromyoma.
N-phenylsalicylamide derivatives are disclosed as a plant growth inhibitor in the specification of U.S. Pat. No. 4,358,443. As medicaments, said derivatives are disclosed as anti-inflammatory agents in the specification of European Patent No. 0,221,211, Japanese Patent Unexamined Publication (KOKAI) No. (Sho) 62-99329, and the specification of U.S. Pat. No. 6,117,859. Furthermore, they are disclosed as NF-κB inhibitors in the pamphlets of International Publication WO99/65499, International Publication WO02/49632, and International Publication WO02/076918, and as inhibitors against the production of cytokines in the pamphlet of International Publication WO02/051397.

Abstract: wherein X represents a connecting group whose number of atoms in the main chain is 2 to 5 (said connecting group may be substituted), A represents hydrogen atom or acetyl group, E represents an aryl group which may be substituted or a hetero aryl group which may be substituted, ring Z represents an arene which may have one or more substitutents in addition to the group represented by formula —O-A wherein A has the same meaning as that defined above and the group represented by formula —X-E wherein each of X and E has the same meaning as that defined above, or a heteroarene which may have one or more substitutents in addition to the group represented by formula —O-A wherein A has the same meaning as that defined above and the group represented by formula —X-E wherein each of X and E has the same meaning as that defined above.

Institute of Medicinal Molecular Design, Inc.


A precedence determination system including a first type memory bank configured to receive a first search signal and to provide first search result indications, a second type memory bank configured to receive a second search signal and to provide second search result indications, a precedence number table coupled to the first and second type memory banks and configured to provide programmable precedence numbers, and a precedence determination circuit coupled to the first and second type memory banks and the precedence number table and configured to provide a third search result indication is disclosed. In one embodiment, the first type memory bank can be a static random access memory (SRAM) and the second type memory bank can be a ternary content addressable memory (TCAM).

In networking systems, classification engines can be used to determine an action to perform and/or a rule to apply to a particular packet. Such classification can include the use of a lookup function, which can be implemented as a hardware "search engine" or the like. Such search engines can include content addressable memory (CAM) and/or a standard memory, such as static random access memory (SRAM). The standard memory is commonly accessed using "hashing" to essentially provide a "many-to-one" function. Such an approach can allow for a smaller memory size so that overall system costs can be reduced. Further, types of CAM include "ternary" CAM, which can allow for matching one of three possible storage states: 0, 1, or "x" (i.e., a "don't care" term).
A search key applied to a search engine, such as a TCAM, can result in several "hit" or "miss" indications. If the search key is found (i.e., a "match" occurs) at multiple locations within the TCAM, a priority or "precedence" determination must be employed in order to provide an overall winner. Referring now to FIG. 1A, a block diagram of a conventional precedence determination using physical address based priority in a TCAM is shown and indicated by the general reference character 100. The search key "Key" can be applied to TCAM 102, which contains a number of entries: Entry 104-0, 104-1, 104-2, . . . Entry 104-N. If the search key matches more than one entry in TCAM 102, search result signals 106 will provide the multiple hit indications to Precedence Determination 108. Of course, this precedence determination may be integrated within the TCAM chip. In any event, the determination in this example is based purely on physical address location. For example, if Entry 104-0 and Entry 104-2 have hit indications, because the address of location 104-0 is lower than the address of 104-2, Entry 104-0 is provided as Result_A by Precedence Determination 108.
More recently, TCAM solutions have incorporated programmable priority override mechanisms to allow for increased flexibility. Referring now to FIG. 1B, a block diagram of a conventional precedence determination using a programmable override based priority in a TCAM is shown and indicated by the general reference character 120. In this example, TCAM 122 contains entries: Entry 124-0, 124-1, 124-2, . . . Entry 124-N. However, each entry is also paired with a corresponding priority override: PO 130-0, 130-1, 130-2, . . . PO 130-N. Here, if the search key matches more than one entry in TCAM 122, search result signals 126 will provide the multiple hit indications to Precedence Determination 128. In this example, if Entry 124-0 and Entry 124-2 have hit indications and if PO 130-2 has a higher priority than PO 130-0, Entry 124-2 is provided as Result_B by Precedence Determination 128 due to the programmable priority override.
While the programmable priority override approach affords increased flexibility for TCAM-based solutions, classification systems having both SRAM and TCAM cannot effectively take advantage of these features. Further, while users can typically shuffle or otherwise change the priority of TCAM entries, it is a more difficult operation to perform using SRAM entries, so a software precedence approach may be more desirable for SRAM. Consequently, what is needed is a precedence determination system supporting overall programmable precedence levels that is suitable for classification systems that have both SRAM and TCAM portions.

Method and apparatus for determining precedence in a classification engine


An imaging system for scanning a volume of interest in an object, the system includes a radiation source configured to traverse in a plurality of focal spot positions yielding a plurality of focal spot trajectories. Each focal spot trajectory defines a two dimensional focal spot projection in an image acquisition plane. Each of the focal spot positions comprise at least two positions at unequal distances from the image acquisition plane.

The present invention relates generally to the field of imaging, and more specifically to the field of tomosynthesis. In particular, the invention relates to tomosynthesis systems and methods employing new scanning trajectories for an x-ray source and a detector to yield an improved image of an object.
Tomography is well known for both industrial and medical applications. Conventional tomography is based on a relative motion of the x-ray source, the detector and the object. Typically, the x-ray source and the detector are either moved synchronously on circles or are simply translated in opposite directions. Due to that correlated motion, the location of the projected images of points within the object moves also. Only points from a particular slice, typically called a focal slice, will be projected always at the same location onto the detector and therefore imaged sharply. Object structures above and below the focal slice will be permanently projected at different locations. Because of that, they are not imaged sharply and will be superimposed as a background intensity to the focal slice. This principle of creating a 3D image with one slice in focus (focal slice) using a discrete number of projections is called tomosynthesis.
Tomosynthesis systems for medical applications, typically use an x-ray source for producing a fan or cone-shaped x-ray beam that is collimated and passes through the patient to then be detected by a set of detector elements. The detector elements produce a signal based on the attenuation of the x-ray beams. The signals may be processed to produce a radiographic projection. The source, the patient, or the detector are then moved relative to one another for the next exposure, typically by moving the x-ray source, so that each projection is acquired at a different angle.
By using reconstruction techniques, such as filtered backprojection, the set of acquired projections may then be reconstructed to produce diagnostically useful three dimensional images. Because the three dimensional information is obtained digitally during tomosynthesis, the image can be reconstructed in whatever viewing plane the operator selects. Typically, a set of slices representative of some volume of interest of the imaged object is reconstructed, where each slice is a reconstructed image representative of structures in a plane that is parallel to the detector plane, and each slice corresponds to a different distance of the plane from the detector plane.
In addition, because tomosynthesis reconstructs three dimensional data from projections, it provides a fast and cost-effective technique for removing superimposed anatomic structures and for enhancing contrast in in-focus planes as compared to the use of a single x-ray radiograph. Further, because the tomosynthesis data consists of relatively few projection radiographs that are acquired quickly, often in a single sweep of the x-ray source over the patient, the total x-ray dose received by the patient is comparable to the dose of a single conventional x-ray exposure and is typically significantly less than the dose received from a computed tomography (CT) examination. In addition, the resolution of the detector employed in tomosynthesis is typically greater than the resolution of detectors used in CT examinations. These qualities make tomosynthesis useful for such radiological tasks as detecting pulmonary nodules or other difficult to image pathologies.
Though tomosynthesis provides these considerable benefits, the techniques associated with tomosynthesis also have disadvantages.
Reconstructed data sets in tomosynthesis often exhibit a blurring of structures in the direction of the projections that were used to acquire the tomosynthesis data. This is expressed in a poor depth resolution of the 3D reconstruction or depth blurring. The degree of depth blurring depends on the scanning parameters, the distance of the object from the plane of interest, and on the size and orientation of the object relative to the scan paths. For example, the traditionally used linear scanning trajectory may lead to a limited z-resolution, and a contrast that may depend on the orientation of the anatomy to be imaged, while the circular trajectory may lead to circular artifacts, caused by out-of-plane structures, that may be mistaken for pathology. The blurring of structures may create undesirable image artifacts and inhibit the separation of structures located at different heights in the reconstruction of the imaged volume. Some existing tomosynthesis reconstruction algorithms address streaking artifacts due to acquisition at discrete focal spot locations, but do not address depth blurring.
Also generally, the solid angular range and complexity of the acquisition projection geometries trade off against the physical limitations of an exam. For example, projection geometries which result from simple linear focal spot trajectories using a flat fixed detector over a small angular range are faster and less demanding of the focal spot positioning apparatus. The smaller exam time mitigates patient motion artifacts for medical imaging applications. However, because the angular range of these projection geometries is small, depth blurring will be more severe in volume reconstructions of objects imaged using such an acquisition configuration. Projection geometries which result from more complex three dimensional focal spot trajectories over a larger solid angular range where a custom geometry multiple surface detector may be repositioned during the scan require a longer exam time, demand more of the focal spot positioning apparatus, demand more of the detector positioning apparatus, and may require additional design considerations for the detector shape. The longer exam time exacerbates patient motion artifacts for medical imaging applications. However, because the solid angular range of these projection geometries is larger, the depth blurring artifacts in the reconstructed volume will be reduced relative to the simpler scan.
Therefore there exists a need to adapt the current tomosynthesis systems to provide for new scanning trajectories to address the depth blurring of the imaged object by using more general projection geometries that may be more suited to reconstructing the region of interest and the anatomy to be imaged.

Method and system for three dimensional tomosynthesis imaging


An element 40 for a metallic belt in a belt-type continuously variable transmission has a structure in which: a belt radial outer portion 46b of a metallic belt 7 is linearly shaped to come into line contact with a pulley radial inner portion 11a which is a constant-angle inclined generatrix portion of a pulley 5 or 8; a projecting portion 48 located below a locking edge portion 44a and extending inward in the belt radial direction is provided at each of the lower ends of both side edges of the element 40; and when the element 40 and a pulley radial outer portion 11b which is a curved generatrix portion of the pulley 5 or 8 contact each other, the projecting portion 48 bends inward in the axial direction of the pulley 5 or 8.

A belt-type continuously variable transmission including a drive pulley, a driven pulley, and a metallic belt wound around the two pulleys is conventionally known (for example, see Japanese Patent Application Laid-Open No. H6-307510).
FIG. 7 shows a deviation Δe in longitudinal center line of a metallic belt 97 in a cross section including the center axes of a drive pulley 98 and a driven pulley 95, in the case where the contact surfaces (hereafter referred to as "V surfaces") between the respective drive pulley 98 and driven pulley 95 and the metallic belt 97 in the cross section are linearly shaped. As shown in FIG. 7, when the gear ratio is changed from maximum (LOW ratio) through intermediate (MID ratio) to minimum (overdrive (OD) ratio), the metallic belt 97 moves in the direction of the center axes of the drive pulley 98 and driven pulley 95 according to changes in width of the pulley grooves of the two pulleys 98 and 95. Here, since the amount of movement of the metallic belt 97 differs between the drive pulley 98 side and the driven pulley 95 side, the deviation Δe in longitudinal center line of the metallic belt 97 changes in the right-left direction, and the orientation 99 of the metallic belt 97 fluctuates right and left (this deviation in longitudinal center line of the metallic belt 97 is hereafter referred to as "misalignment").
If the metallic belt is misaligned in this way, uneven wear occurs in the contact surfaces (V surfaces) between the respective drive and driven pulleys and the metallic belt, or the metallic belt is twisted and as a result decreases in durability.
In Patent Literature 1, misalignment is prevented in the following manner. The inclination angle (the angle with respect to a plane perpendicular to the center axis of the pulley) of the generatrix on the outer diameter side of the pulley is set larger than the inclination angle of the generatrix on the inner diameter side of the pulley to widen the pulley groove, while the boundary portion between the outer diameter side and inner diameter side of the pulley is shaped as a smooth convex curved surface. The side edge of the body portion of each element of the metallic belt is formed in correspondence with the pulley in such a manner that the angle on the outer diameter side of the metallic belt is set to make line contact with the inner diameter side of the pulley and the angle on the inner diameter side of the metallic belt is set to make line contact with the outer diameter side of the pulley.
A continuously variable transmission in which the generatrix from the inner diameter side to outer diameter side of the pulley is a smooth curve to prevent misalignment is also known (for example, see Japanese Patent Application Laid-Open No. 2002-31215).


The present invention discloses a TFT array substrate and a display panel. Multiple pixel electrodes structured with at least one domain are arranged in each pixel area, and the angle/angles of at least one deflection in the same-sided deflections of the pixel electrodes of the same domain in the pixel area in the direction parallel to the initial arrangement direction of liquid crystal not driven by a voltage to rotate is different from the angles of other deflections. Through the design of different deflection angles of the pixel electrodes of the same domain, even under a low gray scale, since the rotating angles of liquid crystal molecules driven by different pixel electrodes are different, the inner parts of the liquid crystal molecules driven by the pixel electrodes may be relatively completely compensated.

In the existing dual-domain design, the design of deflection parts of upper and lower pixel electrodes is shown in FIG. 1. In a pixel area, the upper domain has three pixel electrodes (denoted pixel electrode a, pixel electrode b and pixel electrode c), the lower domain also has three pixel electrodes (denoted pixel electrode a′, pixel electrode b′ and pixel electrode c′), and the three pixel electrodes of each of the upper domain and the lower domain are inclined at certain angles in the direction parallel to the initial arrangement direction of liquid crystal not driven by a voltage to rotate, namely produce deflections; the angles of the deflections produced by any two pixel electrodes of the same domain are the same, namely θ1=θ2=θ3, wherein θ1, θ2 and θ3 are respectively the deflection angles of the pixel electrode a, the pixel electrode b and the pixel electrode c in the direction parallel to the initial arrangement direction of liquid crystal not driven by a voltage to rotate; and the deflections of the pixel electrodes of the upper domain and the lower domain are identical in size but opposite in direction.
In the dual-domain design shown in FIG. 1, when the pixel electrodes are not electrified (i.e., the liquid crystal is not driven by the voltage to rotate), the initial arrangement direction of liquid crystal molecules is shown in the left diagram of FIG. 2; and when the pixel electrodes are electrified, the liquid crystal molecules may be driven to rotate for the same angle as shown in the middle diagram and the right diagram of FIG. 2, thus realizing self-compensation of the liquid crystal molecules, suppressing color shift and tone reversal and improving optical characteristics of visual angle, color shift and the like. However, under a low gray scale, the rotation of the liquid crystal molecules is incomplete (i.e., rotating angles are relatively small), and the inner part of the liquid crystal cannot be completely compensated.

TFT array substrate used in a dual domain liquid crystal display panel and a dual-domain liquid crystal display panel

XIAMEN TIANMA MICRO-ELECTRONICS CO., LTD.


An electric connection box having a main body, a guide wall disposed on the main body for retaining an electric component in a final connected state, and a protrusion disposed on an inner face of the guide wall for preventing movement of the electric component. The guide wall has flexibility and the protrusion contacts with the electric component, with the guide wall being bent outwardly when the electric competent is positioned in the final connected state. The electric connection box further includes a second cover having a locking member; wherein the locking member extends vertically and passes trough an aperture formed in the main body for engaging and locking the electric component.

1. Field of the Invention
The present invention relates to an electric connection box for preventing wear of heavy electric component terminals, such as a relay, and busbar terminals and trunk terminals in the electric connection box, due to movement of the electric component with vibration.
2. Description of the Related Art
FIG. 7 shows an embodiment of a conventional electric connection box (JP, 2000-331759,A).
The electric connection box 71 includes a relay 72, as an electric component, having relay male terminals 73, conductive trunk terminals 76 disposed between an upper cover 74 and a lower cover 75, and busbar boards 77 having busbars 78 with busbar male terminals 79. The relay male terminals 73 are connected with the busbar male terminals 79 through the trunk terminals 76.
The relay 72 turns on and off a main circuit with excitation of a coil in the relay against the busbars 78. The busbars 78 are strip-shaped conductive circuit bodies and have the busbar male terminals 79, which are formed by bending vertically end portions of the busbars 78. The upper cover 74 has a relay attachment portion 80 and a trunk terminal receiving room 81. A lower face of the relay 72 abuts to an upper face of the relay attachment portion 80. The lower cover 75 is fixed to the upper cover 74 and receives a plurality of the busbar boards 77 which are laminated each other.
Each busbar board 77 has the plurality of the busbars 78 separated by insulation substrates made of a synthetic resin. The trunk terminals 76 each have a pair of resilient contact pieces at an upper and lower portion of the vertical substrate. The relay male terminals 73 and busbar male terminals 79 are inserted between the substrate and the resilient contact pieces.
FIGS. 8 and 9 show another embodiment of a conventional electric connection box.
An electric connection box 82 includes an upper cover 83, a lower cover 3, guide walls 51, and flexible locking frames 53, which extend outwardly from the upper cover 83. The guide walls 51 have an L-shape and are arranged to be fitted with corners of the relay 6. The lower portions of the four corners of the relay 6 are guided by the guide walls 51 and locking protrusions 27 of the relay 6 are engaged with the locking frames 53. The relay 6 is usually for a high current and high voltage use.
The upper cover 83 and lower cover 3 are fitted together with flexible side locking frames 10 and side locking protrusions 11. The lower cover 3 has brackets 85 for fixing the lower cover 3 to a vehicle body. A middle plate 47 made of a synthetic resin is disposed above the lower cover 3. The busbars 86 are arranged on the middle plate 47 and between the middle plate 47 and the lower cover 3. Busbar male terminals 49 upstanding from the busbars 86 are connected to the relay male terminals 30 through the trunk terminals 48.
The trunk terminals 48 have resilient contact pieces 63 at middle portions thereof and contact walls 68, 69 opposed to the resilient contact pieces 63. The busbar male terminals 49 and relay male terminals 30 are connected together through the common resilient contact pieces 63.
In the conventional electric connection box 82 of FIGS. 8 and 9, as shown in FIG. 10, spaces S3 and S4 are formed in respective directions of X and Y between the guide walls 51 and the relay 6 when the relay 6 is attached to the relay attachment portion 84. Vibration of a vehicle at running or stopping moves the heavy relay 6 in the directions of X and Y, back and forth and leftward and rightward. This movement causes wears of the relay male terminals 30 and trunk terminals 48 and bends the resilient contact pieces 63 of the trunk terminals 48. As a result of that, the contact pressure between the relay male terminals 30 and the busbar male terminals 49 is reduced.
As shown in FIG. 11, the guide walls 51 are tapered for easy molding. An upper space S5 is larger than a lower space S6. Accordingly, the relay 6 swings inside the guide walls 51 in a direction of C and the relay male terminals 30 swing in a direction D. This movement accelerates the wear of the relay male terminals 30 and the trunk terminals 48 and the bending of the resilient contact pieces 63.
As shown in FIG. 9, there are other spaces S2 and S7 in a direction of Z for locking between the locking protrusions 27 and the locking frames 53 and between the side locking frames 10 and the side locking protrusions 11. An upper wall of the upper cover 83 is deformed with the weight of the relay 6 or the depression force of attachment of the relay 6. The spaces S2, S7 and the deformation of the upper cover 83 change a distance of H2 between an upper face of the lower cover 3, which contacts with the busbars, and a lower face of the relay 6 and a distance of H3 between an upper face of the middle plate 47, which contacts with the busbars, and the lower face of the relay 6. The large changes of H2 and H3 cause the wear of the relay male terminals 30, trunk terminals 48 and busbar male terminals 49.
When a large and heavy fusible link is utilized instead of the relay 6 and the relay male terminals 30 are directly connected to the busbar male terminals 86, not shown, without the trunk terminals 48, the same problems, such as the wear and bending, occur.


According to one embodiment, a document search apparatus includes processing circuitry. The processing circuitry acquires an event text relating to an event, acquire a phenomenon expression from the event text, the phenomenon expression indicating a phenomenon of the event, acquires a synonymous expression having a meaning similar to a meaning of the phenomenon expression, and acquires at least one co-occurrence expression co-occurring with an expression selected from among the phenomenon expression and the synonymous expression. The processing circuitry performs search using the selected expression and one of the at least one co-occurrence expression as search terms to acquire a related-event document relating to the event from document information.

For product designs of, for example, a heat power plant, a hydraulic power plant, a nuclear power plant, an air-conditioning management system for buildings, and a water and sewage management system, it is important for a designer to grasp problems that have occurred with existing products in the past, and prevent the same problems from occurring again. Particularly in the case of the above products, since a long service life is expected, a designer can be involved in only a limited number of product designs. Since the knowledge relating to problems in the past and measures to be taken thereto are mostly dependent upon an experienced designer, unless such knowledge is passed on to a novice designer through guidance, necessary knowledge may not be preserved. Therefore, in recent years, a system has been introduced for storing phenomena, causes, and measures relating to problems that occurred in the past (hereinafter, referred to as nonconforming cases) in a database, and, when a new product is designed, referring to the nonconforming cases that occurred to existing products similar thereto.

Document search apparatus and document search method