1. Field of the Invention
The present invention relates to a lithographic apparatus, a projection assembly and a combination of a structure and an active damping assembly.
2. Background Art
A lithographic apparatus is a machine that applies a desired pattern onto a substrate, usually onto a target portion of the substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, a patterning device, which is alternatively referred to as a mask or a reticle, may be used to generate a circuit pattern to be formed on an individual layer of the IC. This pattern can be transferred onto a target portion (e.g. including part of, one, or several dies) on a substrate (e.g. a silicon wafer). Transfer of the pattern is typically via imaging onto a layer of radiation-sensitive material (resist) provided on the substrate. In general, a single substrate will contain a network of adjacent target portions that are successively patterned. Conventional lithographic apparatus include so-called steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion at once, and so-called scanners, in which each target portion is irradiated by scanning the pattern through a radiation beam in a given direction (the “scanning”-direction) while synchronously scanning the substrate parallel or anti-parallel to this direction. It is also possible to transfer the pattern from the patterning device to the substrate by imprinting the pattern onto the substrate.
The high accuracy and high resolution currently aimed at in lithography require an accurate positioning of parts of the lithographic apparatus such as the reticle stage to hold the mask, the projection system and the substrate table to hold the substrate, with respect to each other. Apart from the positioning of e.g. the reticle stage and the substrate table, this also poses requirements on the projection system. The projection system in current implementations may consist of a carrying structure, such as a lens mount (in case of transmissive optics) or a mirror frame (in case of reflective optics) and a plurality of optical elements such as lens elements, mirrors, etc. In operation, the projection system may be subject to vibrations due to a plurality of causes. As an example, movements of parts in the lithographic apparatus may result in vibrations of a frame to which the projection system is attached, a movement of a stage such as the substrate stage or the reticle stage, or accelerations/decelerations thereof, which may result in a gas stream and/or turbulence and/or acoustic waves affecting the projection system. Such disturbances may result in vibrations of the projection system as a whole or of parts thereof. By such vibrations, displacements of lens elements or mirrors may be caused, which may in turn result in an imaging error, i.e. an error in the projection of the pattern on the substrate.
Commonly, a damping system is provided to dampen vibrations of the projection system or parts thereof. Thereto, a passive damping system may be provided as known in many forms, or a active damping system, or a combination of a passive and a active damping system. In this document, the term active damping system is to be understood as a damping system which comprises a sensor to detect an effect of a vibration (e.g. a position sensor, velocity sensor, acceleration sensor, etc) and a actuator to act on the structure to be damped or a part thereof, the actuator being driven by e.g. a controller in dependency of a signal provided by the sensor. By driving the actuator in dependency of the actuator, i.e. in response to a signal provided by the sensor, an effect of the vibration on the projection system or a part thereof, may be reduced or cancelled to a certain extent. An example of such active damping system may be provided by a feedback loop: the sensor to provide a position quantity (such as a position, speed, acceleration, jerk, etc of the projection system or a part thereof), the controller being provided with the position quantity and generating a controller output signal to drive the actuator, the actuator in turn acting on the projecting system or the part thereof so that a feedback loop is provided. The controller may be formed by any type of controller and may be implemented in the software to be executed by a microprocessor, microcontroller, or any other programmable device, or may be implemented by dedicated hardware.
A problem needing to be solved relates to the stability of the feedback loop, i.e. it is desirable to achieve a frequency behavior of the feedback loop wherein ringing and/or oscillation is prevented. At the same time, a high bandwidth of the active damping system is required, as a high bandwidth of the active damping system will allow to suppress vibrations within such high bandwidth. Due to the ever increasing demands on speed of the lithographic apparatus, movements in the lithographic apparatus tend to take place at a higher speed and consequently involving faster transients, which may result in a generation of vibrations at increasingly higher frequencies. Thus, as speed increases, it is desirable to achieve a higher bandwidth of the active damping system.
A projection system is commonly built up from a variety of parts, comprising e.g. lenses, mirrors and/or other optical elements, lens mountings and/or mirror mountings, a housing of the projection system such as a lens body, etc. As a consequence, a frequency behavior of the projection system starts, at a low frequency extreme, as a rigid body mass, thereby providing a transfer function which is inversely proportional to frequency, as illustrated in FIG. 2, where on a vertical axis a transfer function has been plotted (on a logarithmic scale), while in a horizontal axis a frequency has been plotted (on a logarithmic scale), and where RBM indicates a frequency behavior substantially corresponding to a rigid body mass. In a resonance frequency range RES, a resonance of the projection system is observed, which may be followed by a plurality of further resonance frequencies with increasing frequency, thereby overall resulting in an increase of the magnitude of the transfer function. Effectively, as from the resonance area, the projection system does not behave as a single object anymore, however instead shows a variety of resonance phenomena each corresponding to resonance of an element of the projection system. As a result thereof, the higher the frequency, the lower the remaining mass which “contributes” to the transfer function, which may be considered an explanation for the fact that the magnitude of the transfer function increases with increasing frequency, in the frequency range above the resonance frequency range. As will be understood by a skilled person, the frequency behavior of the projection system as outlined above, may result in stability problems when attempting to achieve a bandwidth of the active damping system which reaches or exceeds the resonance of the projection system. The transfer function may be expressed in terms of e.g. velocity of the projection system as a function of a force on the projection system. It is noted that the transfer function may also be expressed in any other suitable quantity, such as acceleration of the projection system as a result of force on projection system. In that case, a low frequency behavior of the transfer function will show to be frequency independent, followed by a resonance frequency range and an increase of the transfer function (showing multiple resonance peaks) above the resonance frequency range.


1. Field of the invention
The present invention relates to a solar battery type indication apparatus used in road signs, guide signs, or the like, and particularly relates to a solar battery type indication apparatus which is improved to attain reduction both in weight and in cost and eliminate the unevenness of bending of optical fibers to thereby make it possible to perform light transmission securely, receive various parts in a body of the indication apparatus efficiently and connect the optical fibers easily without entanglement in the indication apparatus body.
Further, the present invention relates to an indication apparatus for performing an indication by using light from light-emitting diodes (LEDs), a light source such as a solar lighting apparatus, or the like, and particularly relates to an indication apparatus which is improved in optical fiber-mounting property.
2. Description of the Related Art


1. Field of the Invention
The present invention relates to electrochemical electrodes and, more particularly, to combination electrodes for measuring the ion concentration of solutions.
2. Description of the Prior Art
Combination electrodes comprising a sensing portion and a reference portion incorporated in a glass or a plastic structure are known in the art. One known electrode assembly for measuring pH includes a generally flat, pH-sensitive glass membrane having one face for contacting a sample to be measured and an opposite face contacting an internal electrolyte within the assembly. In addition, a liquid junction is provided between the sample and a reference electrolyte within the assembly. By virtue of its flat ion-sensing structure the electrode assembly is able to measure a small quantity of sample solution on a relatively flat surface without the need to immerse the electrode in a large volume of the solution. Thus, the electrode is particularly suited for measuring, for example, the pH of moisture on the skin of a human subject.
While electrodes of the foregoing nature have performed satisfactorily, they have been confined generally to laboratory, clinical, or other specialized applications requiring trained operating personnel. Further, the sensing portion of such prior electrode assemblies must be carefully positioned on the sample to be measured with the electrode assembly vertically oriented with respect to the sample. This is necessary to ensure that the conventional liquid junction included in the prior art electrode makes contact with the sample and to ensure that any air bubbles within the electrode assembly rise to the top thereof so as not to contact either the ion-sensitive membrane or the liquid junction. If these precautions are not taken, erroneous measurements can result. In addition, the reference electrolyte is generally consumed during normal operation of the electrode and must be periodically refilled. The refilling operation requires a skilled operator to ensure that a proper electrolyte is employed and that no contamination is introduced during the filling operation.
Recently, the need has arisen for a combination electrode assembly which can be operated over prolonged time periods at any physical orientation by non-technical operators. For example, a particular need exists in the cosmetic and hairdressing industry for an electrode assembly which can be routinely employed by hairdressers, beauty operators, and the like for monitoring the pH of a subject's hair, skin, or other body parts. The present invention provides such an assembly.


A semiconductor gas sensor is operated to determine a concentration of a detection gas by using a degree by which a resistance of a detection material such as a metal oxide, a polymer and a carbon nano tube is changed during an oxidation/reduction reaction of the detection gas and the detection material. To this end, the semiconductor gas sensor employs a dedicated heater for a smooth oxidation/reduction reaction of a detection gas and a detection material, and such a reaction is generated in a temperature section of 200 to 500 degrees Celsius.
An electrochemical gas sensor is operated to determine a concentration of a gas through a degree by which a current or an electromotive force is changed while the detection gas and a detection material such as an alkaline metal or an alkaline earth metal carbonate react each other at a high temperature to influence an ion conductivity of a solid electrolyte.
The semiconductor gas sensor or the electrochemical gas sensor employs a heater therein in terms of operation principle. The detection material used for the semiconductor gas sensor or the electrochemical gas sensor mainly includes a metal oxide, an alkaline metal carbonate, a carbon nano tube, graphene or a polymer.
However, a gas sensor according to the related art is known that sensitivity, selectivity and the like are influenced by humidity, that is, water molecules in the air (Jianwei Gong et al., Sensors and Actuators B 114(2006) 32-39). To solve this problem, a study for improving humidity stability of a gas sensor through a filter for adsorbing moisture to a gas inlet port or removing moisture from the gas inlet port while the gas sensor is packaged (U.S. Pat. No. 5,841,021). Such a filter technology helps remove moisture of a part of a gas sensor and secure stability of the gas sensor, deteriorates efficiency of the gas sensor in a situation where excessive moisture is present. And the filter has a limit in life when the filter is stored for a long time. Therefore, a process of replacing a filter after a predetermined time period is required to protect a gas sensor.


1. The Field of the Disclosure
The disclosure relates generally to a system and methods for determining whether an energetic substance or material has experienced a reaction (“go”) or a non-reaction (“no-go”) for storage, transportation or in-process handling, and more particularly, but not necessarily entirely, to a system and methods using a video capturing device, a CPU or computer, sensitivity test equipment, such as an electrostatic discharge device or impact assessment device for testing and assessing the substance or material reaction or explosion sensitivities, and a set of rules or instructions to be followed for quantifying and determining whether a reaction has occurred or not.
2. Description of Related Art
Reaction detection for sensitivity test equipment is not automated. As a consequence, the determination of whether a reaction actually occurred (i.e., a go reaction) or whether a no reaction occurred (i.e., a no-go reaction) is subjective in nature and is based on an operator's varying experience and perception of what actually transpired during a reaction event. Because of the subjectivity of determining whether a reaction occurred or not, standardization of sensitivity test results between laboratories is very difficult to achieve. Standardization between laboratories is possible provided an objective system and methods for determining whether a reaction occurred or not are used.
In the industry, various types of equipment are used to assist an operator in determining whether a reaction occurred or not while testing an energetic material or substance for sensitivity. Some of these operator assisted devices include, but are not limited to, a noise dosimeter, a gas analyzer, a light meter, a strain gauge, and a video capturing device (such as a standard or high-speed camera). One of the best ways in the industry to determine whether a reaction occurred or not is to use a high-speed video capture device for at least the following reasons: (1) it provides a reviewable visual record of the reaction event; and (2) it provides better spatial and temporal visual resolution of the reaction event.
The disclosure is directed to a unique and advantageous system and methods for determining whether a reaction occurred or not using automated equipment, thereby reducing the amount of subjectivity resulting from an operator determination based on an image or collection of images. The automated system and method may use a high-speed video capturing device, sensitivity test equipment, a computer processor and a set of rules or instructions that objectively compares a set of quantified image trial data to a set of quantified image baseline or background data to determine whether a reaction occurred.
An additional difference between the disclosure and what is done in the industry is instead of the operator making a subjective reaction determination based on sensory perception or a less subjective determination using a threshold for auditory, or a gas analyzer, or intensity of light, the operator makes a determination on quantifiable data relating to the acceptable level of error or the likelihood of a false positive and/or a false negative. With that level of error identified, the reaction detection threshold can then be calculated through the use of the system and method of the disclosure. Knowledge of the error or the likelihood of a false positive and/or a false negative allows for much better risk assessment of the sensitivity testing outcome.
The disclosure improves upon known techniques used in the industry by, inter alia, using four unique identifiers or quantifiers relating to the images identified as being of interest and significant. Those identifiers or quantifiers include: brightness, shape, buoyancy, and the uniformity of the event. The disclosure also detects decomposition or reaction of energetic materials. The method and process disclosed may also be advantageous in that multiple characteristics of the images are simultaneously quantified to determine if a reaction has occurred. It is noteworthy that none of the known systems or methods known to Applicant provides the above-identified advantages.
The features and advantages of the disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the disclosure without undue experimentation. The features and advantages of the disclosure may be realized and obtained by the methods and means of the instruments and combinations particularly pointed out in the appended claims. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base, or were common general knowledge in the field relevant to the disclosure as it existed before the priority date of each claim of this application.


1. Technical Field
This invention relates generally to textile sleeves, and more particularly to braided textile sleeves.
2. Related Art
It is known to protect elongate members in textile sleeves against a variety of environmental conditions and affects, or to just contain elongate members in textile sleeves for bundling and routing purposes, such as in knit, woven or braided sleeves. In the case of braided sleeves, the braided wall is commonly braided as a circumferentially continuous, seamless wall, sometimes referred to as a ‘closed’ wall. One known advantage of a closed, braided wall construction is that the wall can be circumferentially expanded to facilitate sliding the wall over an elongated member by manually pushing and physically holding the opposite ends of the wall in a compressed fashion. By pushing the opposite ends toward one another and manually holding the wall in an axially compressed state, the braided wall is caused to take on an increased diameter and a reduced length. When in the increased diameter state, the wall can be readily disposed over the elongate member. Then, after sleeve is installed over the elongate member, the installer can release the wall and the opposite ends automatically spring axially away from one another, thereby taking on a circumferentially decreased diameter and increased length.
Although the aforementioned ability to increase and decrease the diameter of a braided wall has an advantage over some other known types of sleeve construction, such as woven sleeves, it does come with potential drawbacks. Namely, the ability to manually increase the diameter of the braided sleeve requires applying a continual, externally applied compression force during installation, which can prove challenging, and thus, can complicate the ability of the installer to readily install the sleeve over the elongate member. Further complicating installation of a braided sleeve arises when the sleeve has a relatively long length. With the sleeve having a relatively long length, difficultly arises by having to axially compress the opposite ends toward one another without causing the sleeve to fold or buckle along the length of the sleeve. In addition, upon releasing the wall to have the sleeve resume its lengthened, decreased diameter state, the wall generally has a tendency to spring back, at least partially, toward its axially compressed configuration due to a pattern retention phenomenon caused by friction between the interlaced yarns. As such, the effective length of the sleeve can be unintentionally decreased.
It is further known to stretch, cut or tear openings in a sidewall of the sleeve to provide access for branches of wires and branched wire connections, such as with Y or T-shaped connectors. Unfortunately, stretching yarns to form openings is time consuming and can result in inadvertently breaking yarns, while cutting the sidewall typically results in frayed, loose yarns, which not only appear unsightly, but can also diminish the useful life of the sleeve by allowing the opening to become enlarged over time, thereby subjecting the contents to contamination. It is further known to bundle branches and branched connections with multiple sleeves, thereby avoiding having to form openings in a sleeve wall, and further, to use tape about the branches. Although this can prove useful, it is time consuming, cumbersome, and as discussed above, can result in an unappealing appearance, particularly if the tape comes loose. In addition, increased cost is generally associated with having to use multiple sleeves and/or tape.


1. Field of the Invention
The present invention relates to laser scanning systems for reading bar code symbols, and more particularly, pertains to a novel digitizer processing circuit for detecting the times at which a scanning light spot moves from a space onto a bar code symbol or moves from a bar code signal onto a space.
2. Description of the Prior Art
The increased use of bar code symbols to identify products, particularly in retail businesses, has resulted in the development of various bar code reading systems. Many users of bar code readers require portable hand-held scanners which place a premium on small size, lightweight, and low power consumption requirements for the devices. One such system is a laser scanning bar code reading system as described in U.S. Pat. No. 4,496,831, commonly assigned to the same assignee as the present patent application.
The laser scanning system disclosed in U.S. Pat. No. 4,496,831 includes a portable hand-held scanning head which may be embodied in various shapes but preferably has a gun-shaped housing made of lightweight plastic. A handle and barrel portion are provided to house the various components of the scanning head therein. Within the barrel portion are mounted a miniature light source, a miniature optic train including focusing lenses and a scanning system for directing light from the light source across a bar code symbol, and miniature sensing means for detecting reflected light from the bar code symbol being scanned.
The miniature light source can comprise a laser tube such as a coaxial helium neon laser tube, or preferably a semiconductor laser diode which is considerably smaller and lighter than a laser tube, thus reducing the required size and weight of the scanning head and making the scanning head easier to handle and more maneuverable. Light generated by the light source passes through the optic train which directs the beam onto the scanning system which is mounted within the barrel portion of the scanning head. The scanning system sweeps the laser beam across the bar code symbol and comprises at least one scanning motor for sweeping the beam lengthwise across the symbol, and may comprise two motors wherein the second motor sweeps the beam widthwise across the symbol. Light reflecting means such as mirrors are mounted on the motor shafts to direct the beam through the outlet port to the symbol. A sensing circuit then detects and processes the light reflected from the symbol and generally comprises a photodetector element such as a semiconductor photodiode. The user positions the hand-held unit so the scan pattern traverses the symbol to be read, and the photodetector element produces serial electrical signals to be processed for identifying the bar code. A circuit such as that of the present invention for a digitizer signal processing circuit for a bar code produces a signal which is directed to a bar pattern decoder circuit for decoding the bar pattern. The reader unit can have a movable trigger employed to allow the user to activate the light beam and detector circuitry when pointed at the symbol to be read, thereby conserving battery life if the unit is self-powered. The lightweight plastic housing contains the laser light source, the detector, the optics, signal processing circuitry, a CPU, and a battery. The reader is designed to be aimed at a bar code symbol by the user from a position where the reader is spaced from the symbol, i.e., not touching the symbol or moving across the symbol. Typically, this type of hand-held bar code reader is specified to operate in the range of perhaps several inches.
Although the present invention is described with respect to linear or single line bar codes, it is not limited to such embodiments, and may also be applicable to more complex scanning patterns and to stacked or two dimensional bar codes such as Code 49 and similar symbologies. The present invention may also find application for use with various machine vision or optical character recognition applications in which information is derived from other types of indicia such as characters or from the surface characteristics of the article being scanned.
It is well known that it is desirable to locate in time the moment when the center of the moving scanning laser spot is located on the edge of a bar as it moves onto the bar and again when it moves off the bar. It is also well known that there is an inflection point in the analog signal that corresponds to the above-stated moments in time. Various forms of signal processing have been used in bar code scanners to locate these inflection points.
The most common technical approach to accomplish this is to use a zero crossing detector to locate when the second derivative of the analog signal crosses through zero, as this zero crossing corresponds in time to the inflection points of the analog signal. One problem with this approach is that there also are zero crossings of the second derivative that do not correspond to the inflection point of the analog signal. Various technical approaches have, therefore, been developed to distinguish between the desired zero crossings and false ones. Most of these approaches depend upon information obtained from either the analog signal or the first derivative of the analog signal. Examples of these technical approaches are disclosed in Spectra Physics Patent Nos. 4,000,397 and 4,749,879. Another known method is to offset the analog signal by half of its amplitude so that it is centered around zero and then to compare it directly to the second derivative with a voltage comparator. Another common feature is a circuit to ensure noise-free margins the white area on either side of the bar code) by setting a noise threshold based upon the averaging of noise over a period of time. Signals below this average noise level will not be digitized.


1. Field of the Invention
Applicant's invention relates to surgical instruments and, more particularly, to trocars. Trocars are used to pierce or puncture an anatomical cavity to provide communication with the inside of the cavity during a surgical procedure.
2. Background Information
Endoscopic surgery, particularly laparoscopic surgery, is currently becoming a significant method for performing surgeries. It is projected that by the year, 2000 half of all surgical procedures will be performed endoscopically. Laparoscopic surgery has become the surgical procedure of choice because of its patient care advantages over "open surgery."
For the past several decades, endoscopic surgery has been available as a method of diagnosis and, for a very limited number of disorders, a treatment. Until recently, a factor limiting the types of surgeries that could be performed laparoscopically was the ability to employ intraoperative assistance. In the past, endoscopes allowed only direct visualization by the surgeon, such as the endoscope disclosed in U.S. Pat. No. 4,254,762 issued to Yoon. This led to the situation where the surgeon had one hand holding the laparoscope to his eye and then had only one hand available to operate.
Fortunately, miniaturization of video camera computer chips has led to the development of video cameras that can easily be attached to an endoscope or laparoscope. During surgery, connecting a video camera and monitor to the laparoscope enables all the operating room personnel to view the surgical procedure, rather than just the surgeon. Thus, the operating room personnel are able to provide operative assistance just as they do with open surgery. The type and number of surgical procedures amenable to laparoscopic surgery is presently one of the most rapidly developing areas of medicine.
The pivotal advantage of laparoscopic surgery over open surgery is the decreased post-operative recovery time. In many instances, a patient is able to leave the hospital within twenty four hours after laparoscopic surgery has been performed. This is compared to a five day to ten day hospitalization necessary to recover from an open surgical procedure. Additionally, laparoscopic surgery provides a decreased incidence of post-operative abdominal adhesions and decreased post-operative pain with enhanced cosmetic results.
An essential medical instrument for endoscopic procedures is the trocar. Trocars are sharp, pointed surgical instruments used to puncture the wall of an anatomical cavity. The trocar consists of a tube or cannula and a cutting element called an obturator or stylet. The obturator fits within the cannula and has a sharp piercing tip at its end.
A conventional laparoscopic trocar insertion procedure usually follows insufflation of the abdominal cavity with CO.sub.2 gas. The introduction of CO.sub.2 gas into the abdominal cavity lifts the abdominal wall away from the internal viscera. Once this is done, the abdominal wall is penetrated with the trocar. After insertion of the trocar through the abdominal wall, the surgeon removes the obturator leaving the cannula or tube protruding through the body wall. A laparoscope or laparoscopic instruments can then be inserted through the cannula to view internal organs or perform surgical procedures.
Penetrating the wall of the abdominal cavity with the trocar is done quickly. The sharp point of the obturator encounters great resistance from the skin, muscle, and tissue membranes of the abdominal wall while it is being pushed through these structures. Once the trocar's sharp point and blade pass through the abdominal wall and into the cavity, the resistance to the trocar drops quickly. Unless the surgeon immediately stops pushing the trocar just as soon as penetration of the abdominal wall is complete, there is a chance that the trocar will penetrate further into the abdominal cavity and injure internal organs.
Within the abdominal cavity, the obturator's sharp point could easily injure or cut an internal organ upon the slightest contact. If an internal organ is inadvertently injured or cut, unless immediate and massive hemorrhage occurs, the injury may not become apparent until long after completion of the surgery. At a minimum, such an injury will delay a patient's recovery and, more likely, could seriously endanger the patient's health. Additional corrective surgery on an open basis may be required, subjecting the patient to additional risks and costs.
Prior to 1987, the only trocars available for laparoscopic use were instruments made from stainless steel, such as those disclosed in U.S. Pat. No. 3,994,287 issued to Turp et al., and U.S. Pat. No 3,613,684 issued to Sheridan. A problem common to all of these "classic" trocars is that they do not have a safety shield which covers the sharp, cutting tip of the obturator once it pierces the cavity wall.
Several changes and additions have been made on the functional design of these classic trocars. The most significant improvement on the classic trocar is the addition of a spring-loaded safety shield that snaps forward to cover the sharp point and blade of the obturator once the trocar has penetrated the abdominal wall, such as those disclosed in U.S. Pat. No. 4,601,710 issued to Moll, U.S. Pat. No. 4,654,030 issued to Moll et al. and U.S. Pat. No. 4,535,773 issued to Yoon. In these devices, the safety shield is a plastic sleeve which is concentrically mounted to the obturator. Because of this safety feature, trocars with a spring loaded safety shield have become the most used trocars in laparoscopic surgery.
However, these spring loaded safety shields have cumbersome safety shield control mechanisms which are difficult to tell if the safety shield is armed or engaged. To be sure of the safety shield's operation, a surgeon will need to verify the proper operation of the safety shield prior to use. Since the safety shields are mounted to the obturator, surgeons are required to test the safety shield's operation with the obturator in place by manually pressing the safety shield of the trocar. Unfortunately, this results in many slight puncture wounds being experienced by the surgeons as they are attempting to verify the safety shield's operation.
Currently, laparoscopic trocars with the spring loaded safety shields are manufactured only as a thin wall plastic disposable instruments. These light weight plastic instruments are used once and then discarded as medical waste, adding significantly to the already escalating health care costs. For example, the single use disposable plastic trocars cost approximately sixty five dollars to ninety dollars each. Usually two to four trocars are used for each laparoscopic procedure. Thus, surgical costs are unnecessarily increased about two hundred dollars to three hundred and fifty dollars per laparoscopic procedure, as well as adding to the overbearing problem of medical waste by the use of these disposable trocars. Presently, however, the increased health care cost has been unavoidable because the only safety shielded trocar available was a disposable item. No one had invented a easily disassembled, easily cleaned, sterilized, and easily reassembled for reuse, safety shielded trocar.


An image recognition and classification system (a machine vision system) includes a preprocessor in which a "top-down" method is used to extract features from an image, an associative learning neural network system which groups the features into patterns and classifies the patterns, and an attentional mechanism which focuses additional preprocessing and a neural network on relevant parts of an image.
Attempts to recognize and classify images have led to construction of automated artificial machine vision systems and to development of strategies to learn patterns in images and to recognize and classify images by using the learned patterns. Those developing artificial systems have continually attempted to incorporate principles of biological systems into their strategies, because biological systems outperform all artificial systems, implemented or proposed, by a wide margin. For example, machine vision systems based on artificial neural networks have been implemented on digital parallel computers, but a parallel implementation only provides an increase in speed without an increase in performance. Thus, the goal of emulating the pattern recognition performance of biological systems still eludes computer scientists.
In order for a biological nervous system to discriminate objects two fundamental problems must be solved: object segmentation and binding. "Object segmentation" deals with distinguishing separate objects; "binding" deals with how specific attributes such as shape and depth, are linked to create an individual object. A question addressed by object segmentation mechanisms is to which overlapping object does a border belong? An image of an object may be occluded (divided) by an overlapping image, and will need to be reconstructed as a whole image. Models have been proposed to explain this process, for example, using artificial neural networks. (Sajda and Finkel, 1992)
During the past half century, the theoretical infrastructure of machine vision systems has developed both top-down (beginning with large features of the image) and bottom-up (beginning at the lowest level of resolution, usually a pixel) views. However, actual development has focused almost exclusively on bottom-up approaches as exemplified by the title of Pentland's illuminating book From Pixels to Predicates, and comments therein such as: "Processing is primarily data-driven (i.e., bottom-up), although it can be responsive to the goals and expectations at the higher levels." (Pentland, 1986, part 1, page 1).
Ongoing efforts have focused on the extraction of "features" in an image by local manipulations of small micro-features (often 3.times.3 rarely more than 9.times.9 pixel areas), with the intent of identifying larger features (macro-features) from their combination. The paucity of robust results from this approach may be attributed to several causes, two of the most important of which are (1) that the mathematical operations performed on the small areas are usually differential operators such as edge detectors that enhance rather than reduce noise; and (2) that not even humans are very good at visual recognition when allowed only a small instantaneous field of view. Similarity of tactual and visual picture recognition with limited field of view. Loomis et al. (1991).
During this same time period, cognitive psychologists and neurobiologists have made impressive advances in research on the processing mechanisms that are at work in the visual cortex of mammals, particularly cats and monkeys. Electrophysiological and psychophysical experiments on cats and monkeys demonstrate a wide variety of feature selective cells in the visual cortex. In the mammalian cortex, these include simple cells (Hubel and Weisel, 1962), whose shape is closely approximated by a Gabor function (Daugman, 1985; Jones and Palmer, 1987) or a difference of Gaussian functions; end-stopped cells (often called first order hypercomplex cells) (Hubel & Weisel, 1965; Gilbert, 1977); color sensitive cells; and even cells that respond only to faces. (Desimone, 1991). Face-selective cells in the temporal cortex of monkeys. Desimone (1991).
Complex cells and second order hypercomplex cells (Hubel and Weisel, 1962, 1965) are sensitive to the same features as simple and first order hypercomplex cells, respectively. One of the differences among these cells, of interest in the context of feature extraction from static images, is that the complex and second order hypercomplex cells have larger receptive fields than simple cells, and are insensitive to location of micro-features within their receptive fields.
In the development of artificial systems, preprocessing of data derived from an image has been used to extract features from an image and to select features for further processing by machine vision systems. Preprocessing generally proceeds in steps from the "bottom-up," although "top-down" preprocessing has been suggested as a model for human vision. Preprocessing is accomplished by preprocessors, which may be implemented in hardware or software. In some systems, preprocessors have served as the first layer of a two layered neural network. Preprocessing strategies have included subdividing a whole image to be processed into sub-images. Various filters have been suggested to operate on the data, converting the data to a different form or value distribution. Control masks have been used to focus a network on a specific domain of an image.
Prior approaches to the problem of modeling biological preprocessing have been addressed by Grossberg (1988) and Fukushima (1988). For example, the neocognitron neural network developed by Fukushima conceptually models simple, complex, first order and second order hypercomplex cells as well as layers of cells that are sensitive to higher order features. Second order hypercomplex cells are constructed from combinations of first order hypercomplex cells; complex cells are constructed from combinations of simple cells, and the like.
One means of making a complex cell insensitive to location, the approach used by Fukushima, is to design it to receive input from several adjacent simple cells, whose frequency and orientation tuning are similar. The complex cell is made sensitive enough to respond when only one of the simple cells responds to a stimulus. The result is a complex cell with the same frequency and orientation tuning as the simple cells, whose receptive field size is equivalent to the total receptive field size of all its input simple cells combined. Furthermore, the complex cell is insensitive to where in its receptive field the luminance pattern is located (i.e., the complex cell is insensitive to which simple cell has been activated.) Trying to apply biological principles to artificial vision systems, Porat and Zeevi (1989) determined from their work and the work of others, that "primitives of image representations in vision have a wavelet form similar to Gabor elementary functions (EF's)," and proposed a method for texture discrimination in images using a Gabor approach.
Although Porat and Zeevi (1989) proposed that "These localized operators (referring to Gabor functions) are also suitable for a pyramidal scheme of multiresolution which appears to be characteristic of vision, and can also serve as oriented-edge operators and in pattern recognition tasks," (p. 116), they adopted the prevailing approach to the process as a bottom-up hierarchy.
An alternative to extracting features using predefined, generally applicable fixed filters (detectors), such as generated by Gabor and end-stop filters, is to design a system that generates its own feature detectors. In biological systems, the feature detectors must be general enough to handle all possible inputs encountered during the life experiences of the animal. It has been shown that a linear neural network with a correlation rule, when stimulated by random noise, will develop feature detectors similar to the center-surround and Gabor filters found in some artificial visual systems. However, in most practical applications of artificial networks, the universe of possible inputs is more restricted. This suggests that a system for adaptive filter generation that can develop feature detectors specific to the range of images that are encountered in a practical application would be highly desirable. Self-modifying learning algorithms have been pursued wherein a learning algorithm learns about its own effectiveness and modifies itself so that it is the most effective algorithm for solving a certain class of problems.
Despite extensive efforts and much progress, "Forty years of research in artificial neural networks has yielded networks with the neural complexity of, perhaps, a sea slug." (Wenskay, 1991) Image recognition and classification remains a major frontier. The present invention advances toward this frontier.


The endogenous cholinergic neurotransmitter, acetylcholine, exert its biological effect via two types of cholinergic receptors, the muscarinic Acetyl Choline Receptors (mAChR) and the nicotinic Acetyl Choline Receptors (nAChR).
As it is well established that muscarinic acetylcholine receptors dominate quantitatively over nicotinic acetylcholine receptors in the brain area important to memory and cognition, and much research aimed at the development of agents for the treatment of memory related disorders have focused on the synthesis of muscarinic acetylcholine receptor modulators.
Recently, however, an interest in the development of nAChR modulators has emerged. Several diseases are associated with degeneration of the cholinergic system i.e. senile dementia of the Alzheimer type, vascular dementia and cognitive impairment due to the organic brain damage disease related directly to alcoholism. Indeed several CNS disorders can be attributed to a cholinergic deficiency, a dopaminergic deficiency, an adrenergic deficiency or a serotonergic deficiency.
WO 2004/029053 describes 1,4-diazabicycloalkane derivatives useful as modulators of the nicotinic receptors. However, the 1,4-diaza-bicyclo[3.2.2]nonyl oxadiazolyl derivatives of the present invention have not been described.


The present invention relates to a novel concept in genetic engineering, according to which a eukaryotic organism is transformed and crossed so as to provide an offspring including a first exogene in a first chromosome of a chromosome pair and a second exogene in a second chromosome of the chromosome pair, the exogenes exhibiting allelic relationship, such that the exogenes obligatorily segregate to different gametes. The present invention further relates to expression cassettes for implementing the novel concept, to methods of implementing same for the obtainment of reversible male sterility in plants, and further to plants and plant products obtained thereby.
The gene is the basic functional unit of heredity. The gene concept was first set forth by Mendel in 1865 as a result of experiments conducted on pea plants. Mendel proposed that a genetic determinant of a specific character is passed on from one generation to the next as a unit without any blending of the units, a theory now known as the “one gene one trait” theory.
Two of mendel's proposed laws serve as the basis for modern genetics. Mendel's first law states that two members (alleles) of a gene pair obligatorily segregate to different gametes, such that one half of the gametes carry one member (allele) of the pair and the other half of the gametes carry the other member (allele) of the gene pair. Mendel's second law states that during gamete formation the segregation of alleles of a gene pair is independent of alleles other gene pairs.
Following Mendel's research, the discovery of chromosomes and the existence of linkage between genes closely positioned on a single chromosome have further contributed to our knowledge of inherited traits. Nowadays it is known that the second law of Mendel is valid for genes residing on different chromosomes and for genes residing on the same chromosome, provided that they are at least 50 centiMorgan apart, whereas for closer genes residing on the same chromosome, linkage dis-equilibrium is experienced.
Thus, in an individual, a genetic trait in it's simplest form is determined by a pair of closely related sequences known as alleles. Each allele, which is optionally an alternative form of a gene, resides on one of the chromosomes of a chromosome pair. The pair of alleles of a given individual can be identical in sequence or they can differ in sequence to various degree. In meiosis, which is the process of cell division which leads to the formation of sex cells (gametes), the chromosomes of any given chromosome pair segregate into different gametes. This chromosomal segregation is superseded by rearrangement of the DNA in chromosome pairs which takes place via inter chromosomal recombination events.
A specific trait of an individual is determined by a specific combination of two alleles carried by the individual. Thus, traits of an individual are determined by the genetic material inherited by that individual from both parents as determined by chromosomal segregation and recombination events in each of the individual's parents.
Alleles carried on a chromosome pair encode the same genetic trait. Allelic variance ensures a high degree of distinction between individuals.
Transformation of an exogene to a genome is typically random. Assuming one site of exogene integration, a resultant genome is said to be heterozygous of the type 1/0. By careful breeding and selection, a homozygous state for the exogene, i.e., 1/1 is obtainable. Although one can transform a genome with a second exogene (2), it is practically impossible, using conventional transformation techniques, to direct the second exogene to a given integration site, in a different genome. As such, using such conventional molecular biology and breeding techniques, it is practically impossible to achieve exogene allelism of the type 1/2.
Although it is theoretically possible to direct an exogene to a specific chromosomal site by gene knock-in techniques, which therefore could have been used to generate exogene allelism of the type 1/2, such techniques, are very poor in transformation yields. Indeed, no attempts of generating exogene allelism were made so far.
The production of hybrid plants has been practiced ever since the beginning of this century. Plant breeders discovered that crossing two distinct parental lines often resulted in a hybrid plant which displays what is termed as hybrid vigor or heterosis, which is characterized by an increased crop yield and/or adaptation to both biotic and abiotic stresses. Early on, hybrid plant production concentrated mainly on corn and sorghum which were found to benefit from crossing of well compatible parental lines. Later it was discovered that hybrid plant production is also applicable to other plant species.
Several explanations have been proposed for the existence of heterosis. It is clear that a wider allelic variety exist in hybrids plant lines as is compared to inbred plant lines, since the alleles present in a hybrid plant are inherited from two distinct parent plant lines. This allelic variety is favored as a likely explanation for hybrid vigor, however, at present no scientific evidence has been brought forth to support this explanation.
Since hybrid plants have been demonstrated to be superior to inbred lines with respect to yield and vigor, the development of hybrid seeds is one of the prime objectives of the seed industry. In addition, since hybrid plant varieties result from a unique combination, the possibility of duplicating or reusing the hybrid seeds is minimized, thus, providing breeders with an inherent commercial protection.
The production of hybrid seed on a large scale is challenging because many crops have both male and female reproductive organs (stamen and pistil) on the same plant, either within a single flower or in separate flowers. This arrangement results in a high level of self pollination and makes large scale directed crosses between parental lines to generate hybrid plants difficult to accomplish.
To guarantee that out-crossing will occur during the production of hybrid seed, breeders have either manually or mechanically removed stamens from one parental line. Although such manual emasculation is effective for some plants, such as wheat, it is labor intensive and impractical for plants with small bi-sexual flowers. To cross-pollinate such plants breeders have often resorted to using naturally occurring male sterile mutants in efforts to produce hybrid seeds. Although the use of naturally occurring male sterile mutants enables to cross pollinate plants with small bi-sexual flowers, the availability of such mutants and oftentimes the poor genetic makeup thereof severely limited wide spread use of this approach. In addition, using sterile mutants for out-crossing typically results in retention of sterility in a large fraction of the produced seeds. Such seeds when sown would then produce sterile plants which in the case of self pollinator crops such as wheat would lead to no crop yield for a fraction of the plants. To overcome the resultant low crop yield, a breeder is forced to select out the sterile seeds which can be a nearly impossible task.
Since important crops such as rice, wheat are self-pollinating plants with small bi-sexual flowers, there was a need and several attempts were made to develop systems for pollination control to assist in the production of F1 hybrids.
However, several conditions must exist in order to obtain economically feasible F1 hybrid plants. The male sterile line must be 100% sterile and yet female fertile, a natural pollen transfer from the male fertile line to the male sterile line must be facilitated, and in cases of grain or fruit crops, male fertility restoration (MFR) should be enabled in order to obtain crop yield in the F1 progeny.
There exist several mechanisms of male sterility in plants. One such mechanism is cytoplasmic male sterility (CMS). In general CMS has been used in corn, rice, sorghum and onion on a limited basis, see, for example, U.S. Pat. No. 3,861,079 to Patterson.
However, reliance on a single cytoplasmic-male-sterile system for the production of all hybrid plants is undesirable because it leaves the entire hybrid stock vulnerable to plant pathogens. For example, extensive use of one corn cytotype, cmsT lead to an eptiphytic outbreak of Southern Corn Leaf Blight in the early 1970's. Thus, it is important to develop alternative methods to produce male sterile lines in plant species where only a single male-sterility system is available.
An emerging alternative to cytoplasmic sterility is a nuclear sterility. Nuclear male-sterile-based pollination systems rely upon the introduction of a male sterility trait to one parental plant followed by the introduction of a fertility-restorer gene, as a result of cross-pollination, to produce fertile hybrid plants.
Typically, genetically engineered nuclear male sterility is effected by expressing, in a controlled and targeted manner, a protein toxin which destroys anther tissues of the plant in which it is expressed. The expression of this toxin can be either silenced or antagonized in the F1 progeny by the introduction of a fertility-restorer gene, as a result of cross-pollination.
Male reproductive processes in flowering plants occur in the anther. This organ is composed of several tissues and cell types, and is responsible for producing pollen grains that contain the sperm cells. A specialized anther tissue, the tapetum, plays an important role in pollen formation. The tapetum surrounds the pollen sac early in anther development, degenerates during the later stages of development and is not present as an organized tissue in the mature anther. The tapetum produces a number of proteins and other substances that either aid in pollen development or become components of the pollen outer wall. It is known that many male sterility mutations interfere with tapetum cell differentiation and/or function. Thus tapetal tissue is believed to be essential for the production of functional pollen grains.
As such, many nuclear male-sterile-based pollination systems known in the art utilize anther specific promoters to target the destruction of the tapetum or other anther specific tissues during maturation such that subsequent pollen development is arrested.
For example, U.S. Pat. Nos. 5,409,823, 5,659,124 and 5,824,542 to Crossland describe a dual method for producing male-sterile plants. Two genetically transformed plants, parents 1 and 2, are crossed to obtain male-sterile offspring. Parent 1 is transformed with an expression cassette comprising a nucleotide sequence encoding an anther-specific promoter which is operably linked to a nucleotide sequence encoding a trans-activator. Parent 2 is transformed with an expression cassette comprising a target nucleotide sequence, which is capable of being activated by the trans-activator, operably linked to a nucleotide sequence which encodes a toxin which can be an RNA or a polypeptide and which disrupts the formation of viable pollen. Therefore, crossing parent 1 with parent 2 results in male-sterile offspring. The male-sterile plants produced are useful for producing hybrid seed. Subsequent crossing of the male sterile plant with a plant which does not include the trans-activator restores fertility.
Although this system produces desirable male sterility in a portion of the produced offspring, restoration of fertility which relies upon the segregation of the trans-activator gene from the toxin gene cannot be efficiently effected using this system. In the male sterile plant the segregation of these two genes during meiosis relies a great deal on their physical chromosomal location, as such when a male sterile plant is crossed with a plant which does not express the trans-activator, the trans-activator and the toxin can be provided by the male sterile parent as a result of which a portion of the produced progeny will retain undesirable male sterility.
Thus the method by Crossland is not efficiently applicable for self pollinators such as, for example, wheat, cotton and rice.
U.S. Pat. No. 5,929,307 to Hodges describes a recombinant expression vector comprising a suicide gene flanked by site-specific recombination sequences, which vector, when introduced into a plant leads to male sterility. This invention further relates to a second expression vector including a recombinase gene which when introduced into the male sterile plant via a cross-pollinating restorer plant, leads to the deletion of the toxin gene and as a result to the restoration of fertility.
It will be appreciated in this case that since restoration of fertility is effected by a gene product which is introduced via a cross-pollinating restorer plant, a high copy number of the restorer gene must be maintained in the restorer plant such that highly efficient restoration of fertility in the resultant progeny is effected.
Thus, the presently available nuclear male-sterility pollination systems, although generally efficient in the production of male sterile plants, suffer from limitations when restoration of such male sterility via out-crossing is desirable, such as the case for grain or fruit producing hybrid plants. Since these systems cannot enable 100% restoration of fertility to the male sterile plants produced and since the resultant male sterile hybrid seeds are not typically selected out, a suboptimal crop yield from grain or fruit producing hybrid plants produced by these systems results.
There is thus a widely recognized need for, and it would be highly advantageous to have, a male sterile plant, which plant when out-crossed with a compatible male fertile plant generates male fertile offspring in substantially 100% of it's progeny. As further detailed hereinunder, such a plant can be generated by a transformation method which results in formation of allelism between two exogenes. There is thus a widely recognized need for, and it would be highly advantageous to have, a method and expression cassettes for the generation of exogene allelism.


1. Field of the Invention
The present invention generally relates to dispensing a product; and more particularly to a system and method of dispensing prepaid items using a uniquely identified container.
2. Description of Background
Currently, a typical method for dispensing food items, such as soft drinks, is to sell a generic container to a customer who can then fill it at a freestanding kiosk. This method does not insure that the customer will not allow others to use the authorized container for refills, or that only the authorized container is used. This method also does not insure that the container cannot be used beyond the period of time for which the sale was intended.
For systems that dispense items other than soft drinks, for example use of a company gas card at a company gas pump, existing schemes do not insure that the receiving container (usually a vehicle) is authorized. Such is the case for when a company gas card is utilized to fill the gas tank of a personal automobile.


1. Technical Field
The present disclosure relates to sutures and more particularly to sutures made from, incorporating and/or coated with compositions of therapeutic absorbable glass. The present disclosure also relates to pledgets coated with compositions of therapeutic absorbable glass.
2. Description of Related Art
Antimicrobial agents have been associated with surgical devices to prevent contamination with germs. For example, U.S. Pat. No. 5,019,096 to Fox, Jr. et al. describes applying a coating to a medical device, the coating containing a matrix polymer and antimicrobial agents. Other examples of antimicrobial devices include U.S. Pat. Nos. 3,674,901; 3,705,938; 3,987,797; 4,024,871; and 4,612,337.
Sutures prepared from biocompatible bioabsorbable polymers are well known in the art and are described e.g., in U.S. Pat. Nos. 2,668,162; 2,703,316; 2,758,987; 3,225,766; 3,297,033; 3,422,181; 3,531,561; 3,565,077; 3,565,869; 3,620,218; 3,626,948; 3,636,956; 3,736,646; 3,772,420; 3,773,919; 3,792,010; 3,797,499; 3,839,297; 3,867,190; 3,878,284; 3,982,543; 4,047,533; 4,060,089; 4,137,921; 4,157,437; 4,234,775; 4,237,920; 4,300,565; 4,523,591, U.K. Patent No. 779,291; Gilding et al., Biocompatibility of Clinical Implant Materials, Vol. II, ch. 9: “Biodegradable Polymers” (1981). Synthetic biocompatible bioabsorbable multifilament sutures such as DEXON®, VICRYL®, and POLYSORB® commercially available from Ethicon, Inc. (Somerville, N.J.) and United States Surgical (Norwalk, Conn.) are well known in the industry.
Examples of biocompatible non-bioabsorbable polymers useful for fabricating sutures include, but are not limited to, nylon, silk, polyester, polypropylene, polyethylene, cotton, linen, etc. Commercially available sutures fabricated from biocompatible non-bioabsorbable polymers, e.g., a polyester suture (SURGIDAC®, United States Surgical, Norwalk, Conn.) and a polyester braided suture (TICRON®, David & Geck, Danbury, Conn.) are also well known in the industry.
Suture coating compositions are also well known in the art. For example, U.S. Pat. No. 4,027,676 describes an absorbable coating composition for sutures. Other suture coatings are described, e.g., in U.S. Pat. Nos. 4,624,256; 4,190,720; 4,582,052; 4,605,730; 4,700,704; 4,705,820; 4,788,979; 4,791,929; 4,994,074; 5,047,048; 5,100,433; 5,352,515; 5,032,638; 4,711,241; 4,705,820; and 4,201,216.
Water-soluble glasses have been utilized for a variety of medical, cosmetic and other purposes. For example, UK Patent Specifications Nos. 1,565,906, 2,079,152, 2,077,585 and 2,146,531, describe the dissolution of glasses impregnated with various agents such as drugs, hormones, insecticides, spermicides, and fungicides to provide controlled release of these agents. The glass can be in the form of an implant or bolus. WO 98/44965, describes a water-soluble biodegradable glass composition containing various active agents, e.g., antimicrobials such as antibiotics and metal compounds, e.g., silver oxide, silver orthophosphate, steroids, painkillers, etc., which is used for implantation in soft tissue.
WO 96/24364, describes a controlled release glass having various metals, e.g., silver, copper, and zinc useful for combating infections.
WO 98/54104, describes the preparation of water-soluble glass fibres which optionally contain silver compounds. The glass fibres are utilized in undefined orthopaedic implants and tissue engineering applications.
U.S. Pat. No. 5,470,585, describes the use of medicinal substances for topical applications, e.g., wound dressings, which include a water-soluble glass containing a silver compound.
U.S. Pat. No. 4,612,923 is directed to glass-filled absorbable surgical devices made of a synthetic absorbable polymer containing an absorbable glass filler.
U.S. Pat. Nos. 5,290,544 and 5,766,611, describe cosmetic products containing soluble glass which contains silver, copper or zinc ions having antibacterial activity. U.S. Pat. No. 5,330,770, describes a boron-free water-soluble glass containing silver oxide useful as a water treating agent.
While the aforementioned references describe the use of water-soluble glass for certain implant and cosmetic applications, wound dressings, treating infections, and water-treating agents there is no indication in the references of water-soluble glass-based coating compositions for sutures or pledgets, or sutures manufactured from water-soluble glass, which provide controlled, sustained release of a therapeutic agent.


The invention relates to the field of computers, and more specifically to computer buses.
Present day computers comprise bus systems, onto which different devices may be plugged. More specifically, a bus system is often comprised of a bus controller and of a bus connected to the memory controller. Different devices may be connected to the bus, so as to be accessed by the bus controller.
One example of such buses is the DRAM bus designed by Rambus Inc. This bus is used for managing high speed DRAM devices. FIG. 1 is a schematic view of the architecture of this type of bus. It shows the memory controller 1, and the Rambus Channel 2. Several Direct Rambus DRAMs or Direct RDRams (trademark) 3-6 are connected to the Rambus Channel. As shown on FIG. 1, the memory controller as well as each of the RDRAMs comprises a Rambus interface 8 for using the bus. The bus 2 is terminated at one end by terminations, and is also connected to a reference voltage Vref as well as to a 400 MHz bus clock.
According to the Rambus specification, there is also provided a power down mode; it is contemplated in the specification that the power down mode is used for reducing power consumption, notably in portable computers.
Rambus products sold on the market are organised in Rambus RIMM (trademark) memory modules, each module supporting 4, 6, 8, 12 or 16 Direct RDRAMs devices. RIMM modules are compatible with standard motherboard form factors; a motherboard usually supports up to three module sockets. The Direct Rambus Channel signals are daisy chained through each module. See Rambus RIMM Module Preliminary Information, document DL0078 available from Rambus Inc.
There is also provided in the Rambus specification a SPD (Serial Presence Detect) device. The purpose of the SPD is to store and provide sufficient information for a system to initialise the memory subsystem correctly: the SPD is a ROM device provided on each RIMM module, which includes information relating to the DRAM timing and device parameters, core organisation, module parameters, and other system level information. The SPD EEPROM devices of each RIMM module conform to the I2C wire protocol, and may be read into or written into by the memory controller of a Rambus system. See Direct Rambus SPD Specification 1.0, available from Rambus Inc.
FIG. 2 is another view of a physical Rambus architecture, this time in an invalid configuration; it shows the memory controller 1 and the Direct Rambus Channel 2. Three modules 10-12 are connected to the bus; each side of each module may have up to 8 RDRAM devices, referenced again 3-6 on FIG. 2. Reference 13 is the SPD EEPROM of module 10; reference 14 shows the I2C protocol bus used by the memory controller for accessing the SPD EEPROMs of the different modules.
More details on Rambus may be found in the corresponding specification, issued by Rambus Inc. under the title Direct Rambus Technology Disclosure, Oct. 15, 1997.
One problem with Rambus is that the load of the bus is limited to 3 modules, and to 32 Direct RDRAM devices; if one of these limitations is violated, the bus system is not designed to be operational, and or even to boot at all; a computer in which the bus system is installed would in this case not be able to boot either.
This limitation on the number of modules is not likely in practice to be violated, since the bus normally comprises at most three module slots, and usually 2 or 3 module slots. However, a module may comprise up to 16 devices, so that the number of devices on the bus may exceed the highest allowable number of devices. This is the case in the configuration shown in FIG. 2.
Thus, the configuration of the bus hardware is such as to enable the bus to be improperly configured; in this case, a physical layer configuration constraint on the bus can be violated, and proper electrical operation of the bus is therefore not ensured. This can prevent the bus as a whole from booting properly. This possibility makes the system difficult for the user to upgrade or to diagnose problems that occur when they try to.
A variety of bus configuration problems have been addressed in other contexts and a variety of solutions proposed.
For instance, U.S. Pat. No. 5,550,990 discusses physical partitioning of logically continuous buses. This document is directed to the SCSI (Small Computer System Interface) bus architecture, and suggests partitioning the bus into two or more physical entities which to the computer appear as one logical entity. This allows addressing problems potentially arising because of the scope of the architecture to be resolved; one example of such problems is excessive signal degradation due to use of signal rates which although allowed by the architecture are inappropriate for a particular bus loading. The solution disclosed in this document is to provide on the bus an adapter; instead of ensuring physical continuity of the bus, the adapter separates the bus into two bus partitions. This makes it possible, e. g. to operate the two partitions of the bus at different speeds, or to increase the number of devices connected to the bus. Where the speed has to be determined, a negotiation between the adapter and the devices connected to the bus is carried out at the time the adapter is initialised.
U.S. Pat. No. 5,870,571 discusses automatic control of data transfer rates over a computer bus; this document is particularly directed to UltraSCSI buses. This document suggests detecting whether a SCSI external device is connected to the bus, and if this is the case, inhibiting the host adapter in order to reduce the data transfer rates to SCSI rate; otherwise, if no external SCSI device is detected, the UltraSCSI rate may be used, and the host adapter is not inhibited. In this document, the adapter polls the devices connected to the bus at initialisation, in order to know the transfer rate at which they may operate. Note that the operation of devices connected to the bus is not modified, since the host adapter only is inhibited.
U.S. Pat. No. 5,237,690 discusses configuration at boot of IBM PS/2 personal computers. These computers provide a POS (programmable option select) for defining or providing settings for the assignment of system resources to a system board and various adapters. In order to avoid having to reconfigure the computer each time an adapter is added, removed or changed, this document suggests testing at boot of the computer whether any adapter was added, removed or changed; if this is the case, the adapters that were altered are disabled, and the computer is operated with all other adapters.
U.S. Pat. No. 5,797,032 discusses a bus for connecting extension cards to a data processing system, and more particularly and ISA or EISA bus. For addressing the problem of collisions between the addresses of the different cards, this document suggests enabling all cards one at a time, for testing the addresses to which they respond. The cards that generate collisions are then disabled, and a message is displayed on a monitor for indicating to the user which cards were disabled.
The configuration constraints with which these two latter documents are concerned are logical-layer constraints and to resolve associated configuration problems the systems described rely on the buses concerned operating correctly at the physical level.
According to the invention, there is provided a bus system comprising a controller; a high speed data transfer bus, the data transfer bus being subject to one or more inherent physical-layer configuration constraints for proper electrical operation; and a separate control bus, said control bus and said data transfer bus connecting the controller and the, or each, device connected thereto, wherein the controller is arranged to communicate with devices using the control bus in order to verify whether or not one or more of the physical-layer configuration constraints are satisfied and, if such configuration constraints are not satisfied, to modify using control signals transmitted on the control bus the operation of at least some of the devices in order to bring the data transfer bus to an operable condition.
Preferably, if the configuration constraints are not satisfied, the controller is arranged to disable at least some of the devices using control signals transmitted on the control bus in order to bring the data transfer bus to an operable condition. The disabled devices may be the devices furthest from the controller on the data transfer bus. The controller may also be arranged to disable all devices connected to the bus, except one to five devices. The controller may also be arranged to set a stored indicator indicative of a error condition.
In one embodiment of the invention, the physical-layer constraints comprise a constraint on the number of devices connected to the bus.
The invention also provides a computer comprising such a bus.
The invention further relates to a process for bringing a data transfer bus to an operable condition in a bus system comprising a controller; a high speed data transfer bus, the data transfer bus being subject to one or more inherent physical-layer configuration constraints for proper electrical operation; and a separate control bus, said control bus and said data transfer bus connecting the controller and the, or each, device connected thereto. The process comprises the steps of
communicating with devices using the control bus in order to verify whether or not one or more of the physical-layer configuration constraints are satisfied and,
if such configuration constraints are not satisfied, to modifying the operation of at least some of the devices using control signals transmitted on the control bus.
The step of modifying may comprise disabling at least some of the devices using control signals transmitted on the control bus, and for instance, disabling devices furthest from the controller on the data transfer bus. The step of modifying may also comprises disabling all devices connect the bus, except one to five devices. The process may also comprise, if said configuration constraints are not satisfied, setting a stored indicator indicative of a error condition.
In one embodiment of the process, the physical-layer constraints comprise a constraint on the number of devices connected to the bus.
The invention also provides a computer program product for a computer with a bus system comprising a controller; a high speed data transfer bus, the data transfer bus being subject to one or more inherent physical-layer configuration constraints for proper electrical operation; and a separate control bus, said control bus and said data transfer bus connecting the controller and the, or each, device connected thereto. The computer program product comprises a computer readable medium having thereon:
computer program code means, when said program is loaded, to make the controller communicate with devices using the control bus in order to verify whether or not one or more of the physical-layer configuration constraints are satisfied and,
if such configuration constraints are not satisfied, to make the controller modify the operation of at least some of the devices using control signals transmitted on the control bus.
Preferably, if such configuration constraints are not satisfied, the computer program code means make the controller disable at least some of the devices using control signals transmitted on the control bus. The disabled devices may be the devices furthest from the controller on the data transfer bus. The computer program code means may also make the controller disable all devices connected to the bus, except one to five devices. In another embodiment, the computer program code means set a stored indicator indicative of a error condition.
The physical layer constraints may comprise a constraint on the number of devices connected to the bus.
The invention provides a solution to the above described problem. The invention allows a computer at least to boot, even if the bus is improperly configured; this makes it possible to display a message to the user, so that he may address the problem. For Rambus, the mechanical configuration of the bus makes it possible to violate the bus specification by connecting an excessive number of devices on the bus.
In the case of the Rambus system, the limitation in the number of modules and devices connected to the bus is thought to be due to the sensitivity of the high speed signalling used on the Rambus Channel (the RSL or Rambus Signalling Levels) to the number of loads.
In consequence, a number of loads higher than the highest allowable number has no impact on the control bus, and does not affect the RSL signals for a few devices close to the controller. This makes it possible to disable some devices and to allow the bus to operate in a degraded operation mode. This mode is sufficient for booting a computer, and for allowing a warning to be communicated to the user, e. g. by displaying a message, so that they may reduce the number of devices on the bus and fix the problem.
The invention is however not limited to such a problem in the number of devices, but also can be applied in order to resolve other types of improper configuration; for instance, the invention could be applied if the bus can comprise different types of attachable devices, e.g. devices operating at different speeds, or devices requiring a special controller. It could also be applied for solving problems such as the mechanical length of a bus.


The present invention relates to a method of selecting transmission channel in a time division multiple access protocol and to a communication system using the method of the invention.
In the state of the art, for time division multiple access protocols, methods have already been proposed for selecting a transmission channel from a plurality of transmission channels as a function of the transmission conditions measured on each of those channels. These methods apply in particular to the case of a radio transmission between a base station and a set of mobile telephones, the quality of transmission of each channel linking the base station to a mobile telephone varying independently according to the mobility of the telephone and the change in its radio environment.
Thus a method described in document U.S. Pat. No. B1-6,449,490 consists in:                receiving for each channel a value representing the transmission rate currently achievable on that channel;        determining for each channel the transmission rate achieved on that channel during a time window;        selecting the channel for which the ratio of transmission rate currently achievable to the transmission rate achieved during a time window is the highest.
The value of this method relative to a selection method that does not take account of the variations in the quality of transmission of the channels is to increase the transmission rate of each channel by selecting the one on which the transmission conditions are the most favourable. The selection is made on the basis of the ratio of the transmission rate achievable to the transmission rate achieved to provide relatively equitable access to the transmission resource. The drawback of this method is that a channel on which the achieved rate would be limited for a reason other than the sharing of the transmission resource (a constraint linked to the reception capability of the mobile telephone for example) could be selected systematically, even when its transmission conditions are bad.
Another method aiming to take advantage of the independent variations in the transmission quality of the channels and described in the same document consists in:                receiving for each channel a periodic indication of the transmission quality of that channel;        computing for each channel the average transmission quality of that channel;        selecting the channel for which the ratio of the last transmission quality indication to the average transmission quality is the highest.
When applying this teaching of the art, it emerges that certain channels would be allocated a much larger portion of the transmission resource than others. In fact, the distribution of the transmission resource depends on the distribution of the random variations of the transmission conditions of the set of channels. In addition, this distribution of the resource and the transmission quality of each resultant selected channel are extremely difficult to evaluate when the distributions of random variations of the transmission conditions of the channels differ, which is the case in practice.


1. Field of the Invention
The present invention relates to an anti-skid controlling apparatus which controls the braking force applied to the wheels of a vehicle so that the wheels are not locked when braked.
2. Description of the Prior Art
When a running vehicle is abruptly braked and its wheels are locked thereby, the vehicle's purchase on the road surface may become unstable depending on the road surface condition. To prevent the wheels from getting locked in such a situation, the anti-skid controlling apparatus has been conventionally used on board the vehicle. The controlling apparatus controls the brake fluid pressure in the wheel cylinders attached to the wheels so as to optimally decrease or increase the braking force applied to the wheels.
As the brake fluid pressure in the wheel cylinders is raised, the wheel velocity abruptly drops just before the friction coefficient .mu. of the wheels reaches its maximum. This characteristic is utilized by prior art anti-skid controlling apparatus that control the brake fluid pressure in keeping with changes in the wheel velocity and wheel acceleration. The braking force is controlled in this manner so that the slip ratio of the wheels settles at around 20% where a maximum friction coefficient is acquired.
The representative prior art anti-skid controlling apparatus works as follows. The rotating speed of each of the wheels, i.e., the wheel velocity, is first detected. The vehicle velocity is deducted from the wheel velocity. In turn, the vehicle velocity is used to obtain a reference velocity for comparison with the velocity of the individual wheels. The result of the comparison is used to control the brake fluid pressure in the wheel cylinder of each wheel. Japanese Patent Laid-open No. 64-52568 discloses one such anti-skid controlling apparatus. This apparatus distinguishes a "pressure decreasing region" from a "pressure increasing region" in its pressure control setup depending on the slip ratio and wheel acceleration of the vehicle on which it is mounted, each region being variable as required. The disclosure also includes an apparatus capable of lowering the memory size required for skid control.
One disadvantages of the prior art above is that simply separating the pressure decreasing region from the pressure increasing region fails to address the diverse control conditions that vary depending on many factors: different pressure changing characteristics of the pressure controlling means for controlling the brake fluid pressure on different vehicles; different tires; different characteristics of the braking system as a whole from vehicle to vehicle; and different friction coefficients relative to different road surfaces. The above Japanese Patent Laid-open No. 64-52568 discloses that in order to control brake fluid pressure decreases, the pressure decreasing action and pressure holding action are alternated by pulse-based pressure decreasing controls. In this setup, the ratio of pressure decreasing time to pressure holding time is predetermined for the pressure decreasing region. This results in another disadvantage: predestined difficulty in flexibly achieving optimal pressure control.


Light-emitting elements, such as light-emitting diodes, have recently come to be used widely as, for example, a source of light for electroluminescent display panels, or a source of backlight for cellular phones or personal computers, owing to the improved brightness of light thereby emitted. These light-emitting elements are used in packages in which they are stored.
Conventionally, as for a light-emitting element storing package, a light-emitting element storing package disclosed in Patent Document 1 (Japanese Patent Provisional Publication No. 2002-232017) is proposed.
The light-emitting element storing package 100 disclosed in the Patent Document 1, as shown in FIG. 6, has an insulating substrate 111, a reflector frame 112 disposed along the outer periphery of the substrate 111. Furthermore, in the package 100, a light-emitting element storing concave portion 119 is defined between the substrate 111 and the reflector frame 112.
At the position of the concave portion 119 of the insulating substrate 111, i.e. at the just under the position of the concave portion 119, a wiring through-hole (so called “via-hole”) 116, which is penetrated vertically through the substrate 111, is provided.
The wiring through-hole 116 is filled with a conductive member 117 and wiring pattern layers 114 and 115, which are respectively formed on the upper and lower surfaces of the substrate 111, are electrically connected to each other through the conductive member 117. As a result, the light-emitting element 118 mounted on the upper wiring pattern layer 114 may be electrically connected with an external electrical circuit.
After the light-emitting element 118 is mounted on the bottom of the light-emitting element storing concave portion 119, the concave portion 119 is filled with a transparent resin, such as an epoxy resin so that the light-emitting element is sealed gas-tightly. As a result, a light-emitting device as a final product is produced.
In the light-emitting element storing package 100, a light-reflecting layer 113 is formed on the inner wall surface of the concave portion 119, i.e. on the inner wall surface of the reflector frame 112. The light emitted by the light-emitting element 118 is reflected by the light-reflecting layer 113 so that brightness of the light-emitting element 118 is substantially increased.
As a result, the light emitted by the light-emitting element 118 shines brightly by the action of this light-reflecting layer 113, so that an electroluminescent display panel may display bright and very clear characters and images.
As for the light-reflecting layer 113, for example, gold, silver or nickel, etc. is utilized. In addition, for example, a metallized metal layer is previously formed on the inner concave wall surface of the insulating substrate 111 and gold, silver or nickel, etc. is formed on the metallized metal layer by plating, so that the light-reflecting layer 113 is formed on the inner wall surface of the reflector frame 112.
However, in such light-emitting element storing package 100 disclosed in the Patent Document 1, the light-reflecting layer 113 is formed on the whole inner wall surface of the reflector frame 112. Therefore, lower portion of the light-reflecting layer 113 and the wiring pattern layer 114 at the bottom of the light-emitting element storing concave portion 119 is short-circuited, so that there is a possibility of impairing the function of the light-emitting element 118.
For this reason, in a light-emitting element storing package 200 of Patent Document 2 (Japanese Patent Provisional Publication No. 2003-273405), as shown in FIG. 7, a light-reflecting layer 213 is formed on the inner wall surface of the light-emitting element storing concave portion 219 not to cover whole inner wall surface of the reflector frame 212. Moreover, in the package 200, the light-reflecting layer 213 is formed as it is spaced apart from the bottom of the light-emitting element storing concave portion 219.
As a result, the electrical short-circuit between the light-reflecting layer 213 and a wiring pattern layer 214 at the bottom of the light-emitting element storing concave portion 219 is prevented effectively.
Furthermore, in the package 200, an insulating layer 220 is disposed between the light-emitting layer 213 and the wiring pattern layer 214 to ensure the prevention of their electrical short-circuiting.
In addition, in the light-emitting element storing package 200 disclosed in Patent Document 2, as shown in FIG. 7, there is no wiring through-hole in an insulating substrate 211, and a wiring pattern layer 201, which is provided between the reflector frame 212 and the substrate 211, is extended along the outer surface of the substrate 211. As a result, the wiring pattern layers 214 and 215, which are respectively formed on the upper and lower surfaces of the substrate 211, are electrically connected to each other.
However, in the light-emitting element storing package 200 disclosed in this Patent Document 2, the light-reflecting layer 213 is formed as it is spaced apart from the bottom of the light-emitting element storing concave portion 219 and the insulating layer 220 is disposed therebetween. Therefore, the light emitted from the light-emitting element 218 is not reflected by the surface of the insulating layer 220 so that brightness is substantially lowered.
Furthermore, according to both of Patent Documents 1 and 2, the light-reflecting layer is of, for example, gold, silver or nickel. However, gold and nickel have a light reflectance of as low as 50% or less for a wavelength of 400 nm or less. In addition, silver generally has a reflectance of as low as 50% or less for a wavelength of 350 nm or less, since it has absorption at a wavelength of 300 to 350 nm.
However, a light-emitting element for a white LED usually emits blue or near-ultraviolet light and it is converted to various wavelengths by various fluorescent materials. Therefore, it is important for improving its brightness that a light emitted from a light-emitting element having a wavelength of 350 to 430 nm is efficiently reflected.
Therefore, in Patent Document 3 (Japanese Patent Provisional Publication No. 8 (1996)-274378), as shown in FIG. 8, a light-reflecting layer is not formed and an insulating substrate 312 itself formed from a white sintered compact of aluminum oxide having relatively high light-reflecting property. As a result, a light emitted from a light-emitting element 318 is reflected by a light-reflecting surface 320.
In addition, in the light-emitting element storing package 300 disclosed in Patent Document 3, as shown in FIG. 8, a wiring through-hole 316 is formed. The wiring through-hole 316 is extending from the lower portion of a light-emitting element storing concave portion 319 of the insulating substrate 312 to the bottom surface of the insulating substrate 312 through an intermediate wiring portion 313 formed in the middle position of the insulating substrate 312.
The wiring through-hole 316 is filled with a conductive member 317 and wiring pattern layers 314 and 315, which are respectively formed on the upper and lower surfaces of the insulating substrate 312, are electrically connected to each other. Consequently, the light-emitting element 318, which is mounted on the upper wiring pattern layer 314, may be electrically connected with an external electrical circuit.
However, the white sintered compact of aluminum oxide constituting the substrate 312 according to Patent Document 3 has a relatively low thermal conductivity in the order of about 20 W/m·K despite its reflectance of 50% or more for light having a wavelength of 350 to 400 nm. Therefore, the heat from the light-emitting element 318 is thermally accumulated in the light-emitting element storing package 300 and the accumulated heat can not radiate therefrom so that there is possibility of damaging the light-emitting element 318.
Moreover, Patent Document 4 (Japanese Patent Provisional Publication No. 2004-152952) discloses a light-emitting element storing package in which a reflector frame is composed of white ceramics.
However, in this Patent Document, the ceramics actually used for the reflector frame are SiO2—Al2O3—MgO—ZrO2—CaO ceramics having a specific composition, which is mainly consisting of alumina. As apparent from this Patent Document, the ceramic has 96.25% by weight of alumina content so that it has a low thermal conductivity.
Patent Document 4 also states that, as a reflectance of 80% or higher for light having a wavelength of 400 to 700 nm with respect to aluminum nitride (AlN), the amount of Er2O3 in a sintered compact of aluminum nitride is preferably from 1 to 10% by weight based on the weight of the sintered compact.
However, in Patent Document 4, there is no specific embodiment corresponding to this statement. In addition, in fact, it has been confirmed that no white sintered compact of aluminum nitride can be obtained by sintering a material having an Er2O3 content of 1 to 10% by weight (see Comparative Example 4 below).
Patent Document 1 (Japanese Patent Provisional Publication No. 2002-232017)
Patent Document 2 (Japanese Patent Provisional Publication No. 2003-273405)
Patent Document 3 (Japanese Patent Provisional Publication No. 8 (1996)-274378)
Patent Document 4 (Japanese Patent Provisional Publication No. 2004-152952)


This specification relates to using synthetic descriptive text to rank search results.
Internet search engines aim to identify resources, e.g., web pages, images, text documents, or multimedia content, that are relevant to a user's needs and to present information about the resources in a manner that is most useful to the user. Internet search engines generally return a set of search results, each of which identifies a resource, in response to a user submitted query.


1. Field of the Invention
The present invention relates to a differential amplifier circuit and, more particularly to, a differential amplifier circuit wherein the offset voltage is compensated for.
2. Description of the Related Art
FIG. 10 shows a conventional differential amplifier circuit comprising NPN transistors Q1 and Q2, current source A, and PNP transistors Q3 and Q4. Input signals V1 and V2 are supplied to the base of transistor Q1 and the base of transistor Q2, respectively. Current source A is connected between the common emitter of transistors Q1 and Q2 and the ground GND. PNP transistors Q3 and Q4 function as active loads of transistors Q1 and Q2, respectively. The offset voltage of this differential amplifier circuit will be discussed.
The bases of PNP transistors Q3 and Q4 are mutually connected, and the emitters of these transistors are coupled to power-supply Vcc terminal. Therefore, the base-emitter voltage Vbe3 of transistor Q3 is equal to the base-emitter voltage of transistor Q4. Hence: EQU (Ic3/Is3)=(Ic4/Is4)
where Ic3 is the collector current of transistor Q3, Ic4 is the collector current of transistor Q4, Is3 is the reverse saturation current of transistor Q3, and Is4 is the reverse saturation current of transistor Q4.
The collector current Ic2 of transistor Q2 is given: EQU Ic2=Ic4=Ic3(Is4/Is3)
The collector current Ic1 of transistor Q1 is given: EQU Ic1=Ic3(1+2/.beta.p)
where .beta.p is the current-amplification factor of PNP transistors Q3 and Q4.
Thus, the offset voltage Vos of the differential amplifier circuit shown in FIG. 10 is: ##EQU1## Here, let us assume that: ##EQU2## Then, the offset voltage Vos can be represented as follows: ##EQU3## Since .DELTA.Isp<<Isp, and .DELTA.Isn<<Isn, this equation reduces to: ##EQU4## Here is the relationship: EQU ln(1+x)=x-(x.sup.2 /2)+(x.sup.3 /3) . . .
And .DELTA.Isp/Isp<<1, .DELTA.Isn/Isn<<1, and 2/.beta.p<<1. Therefore, the second term et seq. of the above equation can be neglected. Hence: ##EQU5## The values of .DELTA.Isp/Isp and .DELTA.Isn/Isn, both included in equation (1), are determined by the characteristics of the transistors used in the differential amplifier circuit. The third term in the right side, i.e., 2/.beta.p, is a factor which is determined by the structure of the circuit and the characteristics of the transistors used therein.
Assuming that V.sub.T =26 mV, .DELTA.Isp/Isp=5%, .DELTA.Isn/Isn=5%, and .beta.p=10, then the worst value for Vos will be: EQU Vos=26 (0.05+0.05+0.1)=7.8 mV
Hence that portion of the offset voltage which is determined by the their term in the right side of equation (1) is 2.6 mV (=26.times.0.1).
As has been pointed, the third term in the right side of equation (1) is determined by the structure of the circuit and the characteristics of the transistors used in this circuit. When PNP transistor Q5 is added to the circuit shown in FIG. 10, with its base coupled to the collector of transistor Q3 its emitter connected to the common base of transistors Q3 and Q4, and its collector connected to the ground, as is illustrated in FIG. 11, then, equation (1) changes to: ##EQU6##
When factors which are similar to those mentioned above, is applied, then: EQU Vos=26 (0.05+0.05+0.0182)=3.07 mV
In the circuit shown in FIG. 11, that portion of the offset voltage which is determined by the third term in the right side of equation (2) is 0.47 mV (=26.times.0.0182), far lower than the corresponding portion of the offset voltage of the differential amplifier circuit shown in FIG. 10. Nonetheless, the offset voltage (i.e., 2.6 mV) of the circuit is still too high.