An exercise data collection system and method of collection of data concerning the performance of weightlifters and the like which can be retrofitted for use with a power rack or half rack used by weightlifters and detached after use or alternatively set up in a freestanding arrangement, such as for use on a platform, in which by emitted electromagnetic radiation coupled detectors the movements of a barbell past such emitters is detected by the reflected emission and the speed of passage calculated by determining the interval between reflection of the detector beams between adjacent detectors, the height of such reflection beam being related to the portion of the musculature of the weightlifter that is undergoing extension or retraction during exercise.

1. Field of the Invention
The present invention relates to the fields of exercise devices and weightlifting, and more particularly the present invention relates to a system and method for measuring and tracking certain exercise parameters when performing a weightlifting exercise, and more particularly still to a portable free-weight exercise data gathering and feedback system and method whereby a motion sensor means connected to an electronic evaluation circuit and a means for displaying data concerning the exercise movements performed is provided.
2. Preliminary Discussion
Most newer weightlifting type exercise devices today are weight stack type machines, wherein a vertical stack of weights or plates is slidably arranged on guides, and a pulley, lever, and cable system including a handle is used by an exerciser to perform pulling, pressing, or lifting repetitions. Typically, the user selects the amount of weight to be lifted by placing a pin in the stack such that it passes underneath a particular or set number of weight plates and secures them to the guides. Despite the current popularity of such machines, which is due to their ease of use and the easily adjusted variable resistance of such machines, not to mention the safety feature of having the weight stack operate on guide rods, most serious or competition level weightlifters prefer to train in large part using free-weights, such as barbells and dumbbells, particularly when training using very heavy weights. While weight stack machines can be used to isolate and train particular muscles, such machines usually cannot mimic the natural lifting motion of a free-weight exercise closely enough to satisfy seriously training or elite athletes. In addition, free-weight lifting uses only the leverage created by the user's body and muscles, and is not supplemented by a machine. Competitive weightlifters, furthermore, are likely to train using free-weights rather than machines in training for their particular lifting event.
The most common free-weight exercises performed using a barbell with heavy weights are squat exercises and exercises using a so-called bench press. In performing a squat or squat lift exercise, which is essentially a deep knee bend, a frame apparatus, often referred to generally as a "power rack", is often used to aid the exerciser in grasping and positioning the barbell on his or her shoulders, so that the exercise is performed in a safe manner preventing injury to the weightlifter or possibly to bystanders. Bench press routines are also frequently performed in the confines of a frame or power rack apparatus. A power rack typically consists of a rectangular frame made of steel tubing comprised of pairs of front and rear vertical uprights or corner posts, usually also rectangular, connected together at their upper and lower ends to form a rigid open protective structure. Each vertical upright typically is provided with a series of spaced apart and aligned apertures or through-holes into which horizontal spotter arms or barbell support hooks may be adjustably secured. To perform the squat exercise, the barbell is placed on the support hooks at a height just below the shoulders of the exerciser. The exerciser will then position the barbell across his or her shoulders, grasp the barbell, lift the barbell upwardly slightly so that it is removed from the support hooks, move to a comfortable position away from but between the front and rear vertical uprights in the center of the rack, and perform the squatting exercise with all of the weight of the barbell being supported by the exerciser. As the barbell is moved upwardly and downwardly between the pairs of vertical uprights of the power rack, the outer ends of the barbell are long enough so that they extend beyond the outer edges of the front and rear corner posts of the rack. So-called horizontal "spotter" bars are thus often positioned extending between the front and rear posts at a height just below the lowest point of the range of motion of the squat exercise to serve as a safety barbell catching means. If the lifter is unable to complete a repetition or starts to lose control of the barbell, he or she can if possible place the barbell back on the support hooks, or if not possible he or she can simply rest it on or drop it completely on the horizontal spotter bars.
In addition to the simple frame or power rack apparatus described above, a large number of modified power rack devices are available. For example, the well known so-called "Smith machine" includes barbell guiding elements on or adjacent the front vertical uprights to which the barbell is rigidly connected. The guiding elements slide up and down on the vertical uprights as the squat exercise is performed, which keeps the barbell level during each repetition. In addition, a latch means on the barbell enables it to be hooked and unhooked from the upright at various vertical positions by twisting the barbell to move the latch toward or away from the apertures. Half racks, wherein there are only two vertical posts or uprights rather than four, are also increasingly popular. Other free-weight exercises, such as the bench press, curls, and the like, can be performed using the power rack or Smith machine, as well as one or more similar frame apparatus devices such as the half rack. Nevertheless, most serious weightlifters usually prefer to use the basic power rack, since the lifting motion is not restricted to a strictly up and down or vertical motion, which is somewhat unnatural.
As indicated above, frame apparatus such as the power rack, half rack, or other similar specialized machines and devices enable squat or other free-weight exercises to be performed more safely without the assistance of a human spotter, as such racks, in effect, include an integral safety spotter. While such equipment enables the exercises to be performed more safely, there is usually no means for providing exercise parameter feedback to the user. Weightlifters will typically keep a log book or record listing each exercise performed, the number of repetitions, and the amount of weight lifted in each exercise. In this way, the weightlifter can compare the amount of exercise accomplished during one period with the amount of exercise accomplished during the previous period, thereby monitoring his or her performance over time. However, while such data is certainly useful, it is also quite limited and gives little indication as to the manner in which each exercise or repetition is performed. For example, on one day a squat exercise might be performed at a faster pace or with a fuller range of motion than on another day, or the exerciser may fatigue more quickly and his or her pace may be faster over the first several repetitions but may slow over the later repetitions. In each instance, the exerciser will likely only record in his or her log book the number of repetitions completed, with no further indication as to the manner in which the repetitions were completed, except for possibly a few usually one or two words comments. Little feedback information or data, therefore, is available to the exerciser that may aid him or her in exercising in a more efficient or proper manner.
Recognizing the need to provide more detailed exercise parameter data and feedback to weightlifters, and in particular to those performing free-weight exercises, the present inventor has now provided a retrofittable detection device mountable on a power rack or similar apparatus such as a half rack which uses simple electronic detection means to provide detailed data concerning the performance of weightlifting exercises performed using a safety apparatus such as a power rack, half rack, or the like, although the device is also capable of being used in a freestanding orientation.
3. Description of Related Art
A search of the prior art references has revealed a large number of inventions related to the field of monitoring performance of an exercise and providing exercise parameter data or feedback to an exerciser. However, none provide the data in the manner and variety or as conveniently as the system of the present invention or anticipate or disclose the device and method of the present invention. The most relevant patent references known to the present inventor are discussed hereinbelow.
U.S. Pat. No. 4,907,795 issued to B. F. Shaw et al. on Mar. 13, 1990, entitled "COMPUTERIZED EXERCISE MONITORING SYSTEM AND METHOD OF MONITORING A USER'S EXERCISE PERFORMANCE," discloses a system for comparing one's exercise performance with past performances, thereby encouraging a more efficient workout. Provided is a portable memory unit that can be plugged into various weight stack type exercise machines and then used to record exercise data. Each weight stack machine used with the memory unit has a screen or monitor for displaying such performance data attached. Shaw et al. utilizes a disc situated between infrared detector sensors and having spaced holes in it. The disc rotates in response to movement of a chain attached to the weight stack. Pulse signals from the infrared detector sensors caused by interruption of the beam by the rotating disc are sent to the computer system, which uses the pulses to track the position of the weight stack. The Shaw system therefore depends upon movement of the weight stack chain to move the disc and to interrupt the infrared signal, and therefore is not designed to be used in a free-weight lifting environment.
U.S. Pat. No. 5,260,870 issued to K. Tsuchiya et al. on Nov. 9, 1993, entitled "APPARATUS FOR MEASURING INSTANTANEOUS POWER BY LEG-STRETCHING POWER," discloses an apparatus for measuring one's leg power including a seat, drive system unit, a slide rail having a foot plate slidably secured, foot load and rotation frequency sensors, and a control panel having an LED display. When the user presses his or her feet against the foot plate, the device calculates the foot pressing force, average power, and the like. Tsuchiya et al. does not teach the use of light sensors to detect a range of motion as in the present invention, however.
U.S. Pat. No. 5,314,394 issued to J. J. Ronan on May 24, 1994, entitled "SPOTTING APPARATUS FOR ASSISTING A WEIGHTLIFTER," discloses a unit for assisting a weightlifter upon partial muscle failure during a workout, as well as a system for monitoring the position of a weight within a range of movement. The barbell is supported on arms connected to a slidable arm support assembly in turn connected to a support structure, which also includes a counterweight and a power assist unit. A lower position sensor detects when the barbell has been moved to a low position and activates the power assist unit to aid in lifting the barbell. A speed sensor detects the speed and direction a wheel is moving, which activates the power assist if the control unit determines that the barbell is moving too quickly or slowly. While Ronan illustrates a weightlifting apparatus having various sensors for measuring the rate or speed of movement of a barbell during exercise, such sensors are not light sensors. In addition, the Ronan apparatus is primarily a lifting assist device, rather than a system for monitoring one's exercise performance. Furthermore, the barbell is coupled to the apparatus, which limits the range of motion of the lifting exercise.
U.S. Pat. No. 5,331,851 issued to A. Parviainen et al. on Jul. 26, 1994, entitled "METHOD FOR MEASURING THE WORKING CONDITION OF MUSCLES AND MEASURING AND TRAINING SYSTEMS FOR MEASUREMENTS OF THE WORKING CONDITION OF MUSCLES AND FOR MUSCLE TRAINING." discloses an exercise measurement system and method wherein, broadly speaking, sensors connected to a data processing unit and display screen are attached to a piece of exercise equipment to measure and monitor various conditions experienced during muscle training. While the Parviainen et al. machine can calculate or detect parameters such as force, range of motion, rate of fatigue, and power, the system is designed for use with a weight stack-type machine, rather than in a free-weight lifting environment as with the present invention.
U.S. Pat. No. 5,458,548 issued to I. F. Crossing et al. on Oct. 17, 1995, entitled "FITNESS QUANTIFICATION EXERCISER," discloses a device, preferably a potentiometer, which acts as an encoder and generates pulses which detect the degree of movement of a shaft. The pulses are fed into a micro processor, and the number of pulses is then used to calculate the distance traveled by the exerciser. In addition, a heart monitor is worn by the exerciser to measure his or her heart rate, which information is then processed and displayed on a display screen.
U.S. Pat. No. 5,653,669 issued to C. L. Cheng on Aug. 5, 1997, entitled "UNIVERSAL GYM WITH UNIFORM RESISTANCES," discloses a cable-type weightlifting apparatus having a lever-type strain gauge for detecting the force applied during exercise, which measurement is conveyed to the user via a monitor or similar display means. While the Cheng lever-type strain gauge as shown may be unique in combination with a universal gym, such invention is not similar to the present inventor's arrangement, and Cheng does not teach the use of light sensors to obtain data concerning exercise repetitions.
U.S. Pat. No. 5,655,997 issued to A. D. Greenberg et al. on Aug. 12, 1997, entitled "FITNESS FEEDBACK SYSTEM FOR WEIGHT STACK MACHINES," discloses a system for conveying exercise parameter data to users of weight stack type exercise machines. As the cables supporting the weight stack are moved, an encoder attached to the weight stack pin by a cable converts the linear motion of the cable and weight stack into a series of electrical impulses which are transmitted to an assembly that computes the speed and distance of the cable movement as detected by a pair of proximity sensors, which are aligned vertically with the weights. The proximity sensors may be photosensors which detect a reflective tape on the weight plates, with a light source placed on one side of the weight stack and light detectors placed so as to detect motion of the weight stacks and the number of weights in a stack. The computations are then displayed on a display device. Greenberg et al. provides a means for obtaining data by measuring the movement of a weight stack using sensors. However, Greenburg et al. does not use multiple light sensors to measure multiple ranges of motion of the weight stack, and therefore is incapable of matching the accuracy of the speed, direction, and other measurements taken using the present inventor's system. The light detectors also are not mounted or movable as in the present invention, which is designed primarily for use in free-weight lifting, rather than with weight stack machines. See also U.S. Pat. No. 5,785,632 also issued to A. D. Greenberg et al. on Jul. 28, 1998, entitled "FITNESS FEEDBACK SYSTEM FOR WEIGHT STACK MACHINES," which is a divisional patent of U.S. Pat. No. 5,655,997.
U.S. Pat. No. 5,667,460 issued to R. S. Smith on Sep. 16, 1997, entitled "BALLISTIC FORCE EXERCISER," discloses a means for measuring ballistic force, or the force generated by momentum exchange during a weightlifting exercise repetition. A time switch and counter switch are connected to an upright of a power rack, which records the lowering and raising of the barbell, from which the ballistic force can be measured. While Smith illustrates a unique system for measuring one's exercise performance, Smith does not include a light sensor means for determining the position of the ends of a barbell at various points in a weightlifting exercise repetition, or a similar display means for displaying such information. The Smith invention also is not designed for use in free-weight lifting, as the barbell is rigidly and slidably connected to the power rack in such invention.
U.S. Pat. No. 5,827,154 issued to J. C. Gill on Oct. 27, 1998, entitled "CONCENTRIC/ECCENTRIC EXERCISE APPARATUS," discloses a leg exercising machine having a control for monitoring or selecting the speed at which the apparatus can be moved, including both positive and negative movements. Such apparatus is provided primarily as a safety feature rather than an exercise measuring feature.
U.S. Pat. No. 5,916,063 issued to N. Alessandri on Jun. 29, 1999, entitled "PORTABLE MEMORY-MEDIATED SYSTEM AND METHOD FOR PROVIDING CUSTOMIZED TRAINING PROGRAM FOR USER OF PLURAL UNITS OF EXERCISE APPARATUS," discloses an exercise system wherein each exercise apparatus in a gym or workout area is connected to a central system computer so that exercise results taken from any single piece of equipment can be monitored and gathered into an overall workout regimen. While such system includes a graphic display for such information, and can monitor one's workout schedule and provide feedback concerning the timing and intensity of such workouts, Alessandri does not appear to anticipate the present inventor's system and method for improving one's training on a free-weight lifting apparatus.
U.S. Pat. No. 6,149,550 issued to D. Shteingold on Nov. 21, 2000, entitled "MUSCLE STRENGTH TESTING APPARATUS," discloses a bar-like apparatus hingedly connected between two vertical posts. A plurality of tension sensors, preferably piezo-electric sensors, are provided so that when a force is applied to the apparatus, such force is computed and a reading is displayed on a display unit. A horizontal force measuring unit is also provided secured to each post. While Shteingold uses sensors to determine exercise parameter data, such sensors respond to tension as opposed to the light sensors used by the present inventor, which record when a barbell passes through or interrupts the light path.
U.S. Pat. No. 6,190,287 issued to L. M. Nashner on Feb. 20, 2001, entitled "METHOD FOR MONITORING TRAINING PROGRAMS," discloses a workout monitoring means including a display and a remote computer controlling or monitoring device attached to an exercise quality and quantity measuring device, such as a force plate. Nashner uses mathematical algorithms to measure performance, but the physical movements of the user are not measured using sensors to determine the range of motion of such exercise.
U.S. Pat. No. 6,224,512 issued to U. Arnesson on May 1, 2001, entitled "TEST AND TRAINING DEVICE AND METHOD," discloses a method and device for performing static and dynamic strength tests as well as for training the leg and knee areas. Such device includes a force measuring means, a display screen, and a keyboard for controlling the device, but light sensors are not used to record data related to each exercise performed.
U.S. Pat. No. 6,228,000 issued to A. A. Jones on May 8, 2001, entitled "MACHINE AND METHOD FOR MEASURING STRENGTH OF MUSCLES WITH AID OF A COMPUTER," discloses an exercise device including a force measuring device such as a strain gauge which measures the force exerted by an exerciser to determine the strength of such person's muscles. A device for measuring the angle of one's body is also provided. Such information is then displayed on a screen. Although the invention is used with a variety of different exercise machines, a light sensor does not appear to be used in any of such different embodiments.
U.S. Pat. No. 6,231,481 issued to K. B. Brock on May 15, 2001, entitled "PHYSICAL ACTIVITY MEASURING METHOD AND APPARATUS," discloses an apparatus for measuring the power generated by an exerciser, which apparatus may be used either with free weights, free weight machines, or cable-type machines. Exercise parameters such as velocity and acceleration are measured and displayed on a display screen. Although infrared or laser sensors/transducers may be used with the invention, Brock shows only mechanical connections and does not arrange one or more pairs of light sensors to a weightlifting power rack apparatus or in a freestanding arrangement to measure exercise movements as in the present invention.
U.S. Pat. No. 6,261,205 issued to P. M. Elefson on Jul. 17, 2001, entitled "RESISTANCE TRAINING APPARATUS," discloses a vertical rack support upon which a barbell may be mounted or clamped. The apparatus detects when movement of the barbell is decelerated in a positive movement as a result of tiring of the exerciser and begins to aid in moving the barbell, or if the negative movement is accelerated in a negative direction as a result of tiring, the device will slow the movement. The machine replaces a human spotter in the practice of so-called forced repetition by weightlifters. The device is therefore basically a variation of the Ronan disclosure of the U.S. Pat. No. 5,314,394 patent.
U.S. Pat. No. 6,358,188 issued to R. Ben-Yehuda et al. on Mar. 19, 2002, entitled "EXERCISE TRACKING SYSTEM", discloses a tracking system wherein reflectors are placed on a side edge of each plate in a weight stack, while a detector connected to a computer via either a hard wire or wireless connection is placed adjacent the reflectors. A user interface including a display screen and card reader is connected to a computer. The detector includes a light source aimed at the reflectors on the weight stack and a light detector, so that during exercise the movement of the weights is detected, with the time of reflections being indicative of the speed and direction of a lift. Using such measurements, various data can be calculated. Since the Ben-Yehuda system depends on reflection of light off of the weight stack, such system could not be adapted for use when lifting free-weights with a power rack or even using a "Smith machine" arrangement. In addition, the use of multiple pairs of detectors enables the present inventor to generate more detailed exercise parameter data than is possible with the Ben-Yehuda et al. system.
U.S. Patent Application Publication No. 2003/0032529 by N. Alessandri et al. and published on Feb. 13, 2003, entitled "Remote Measuring Device for an Exercise Machine with Counterweights", discloses another measuring system for use with weight stack type exercise machines, whereby a signal indicative of the position of the weight stack pin is generated by an element attached to the pin, and such signal is detected by a stationary detection device. Such signal is preferably an ultrasonic signal, although visible or infrared light waves may be used.
German Patent No. DE 3807038 C1 issued to P. Beutel and published on Sep. 28, 1989, entitled "Arrangement for Collecting Training Data for Mechanical Training Equipment", discloses an electronic control unit that is attached to a piece of training equipment for collecting and recording training data. A portable data carrier is used to output the data, which is collected by a contactless sensor such as a magnetic proximity sensor which senses movement of the training equipment. For example, the sensor may be placed adjacent a weight stack, a permanent magnet attached to each plate in the stack, and movement is sensed and recorded, and then shown on an LCD display. Such arrangement is not closely similar to the present inventor's light bar system and method.
German Patent No. DE 3914437 C1 issued to H. Leutheuser and published on Nov. 16, 1989, entitled "Device for Carrying Out Training Exercises", discloses an exercise apparatus having a sensor device for sensing movement of the user or apparatus that is operably connected to an electronic circuit for evaluating the signals detected by the sensors. The sensor device is comprised of an electro-optical transmitter, such as an LED light, and a receiver, so that when the light is interrupted, such interruption is detected and recorded. From this data, simple exercise parameters such as the number of repetitions may be determined. Heinz however uses only a single light sensor to record movement of a barbell or the like, so that the amount of data available is severely limited in comparison to the present inventor's multiple sensor arrangement, wherein detailed information concerning single repetitions as well as overall and historical workout data can be determined.
While the use of sensors to detect and record exercise repetitions and movements is therefore shown in various references available in the prior art, and while each of the devices disclosed in such references is useful in its own respect, none of the known arrangements solves the problems addressed by the present invention, wherein multiple measurements are taken and evaluated during single exercise repetitions by electromagnetic wave detection apparatus, preferably infrared light beams. For example, during a bench press or squat exercise, the present inventor may position multiple sensors on either side of the barbell being lifted. As the barbell is moved within a range of motion during each repetition, such movement will by or through interruption of the light beam by the barbell be detected and recorded by each sensor device. For such measurements, in addition to simple calculations such as the number of repetitions completed, a multitude of additional data is available, such as whether the barbell is moving at a slightly faster speed during certain parts of the repetition, whether the barbell is being held parallel or whether it is leaning to one side so that one side is being lifted ahead of the other, and the like. Such detailed information is extremely valuable in evaluating and improving one's exercise routine, and may be used to ascertain certain strengths and weaknesses of the exerciser, as well as to track the exerciser's progress over time. By detecting certain patterns or weaknesses, such weaknesses can be addressed and corrected, thereby improving the overall conditioning process. Applicant's apparatus, furthermore, is designed in one embodiment to be easily and conveniently mounted upon existing power racks or half racks either as a permanent retrofit or as a temporary provision of data collection apparatus provided for a particular weightlifter, and may be designed and or calibrated especially for a particular weightlifter enabling lifters to have available their own lift measuring system in a gym environment. Alternatively, the apparatus may be provided in a freestanding arrangement and used with a conventional bench press or other exercises wherein a weight, limb, body part, or other device is repeatedly moved through a range of motion, or even completely embedded in the frame of a power rack or half rack. The apparatus and method are particularly designed for use in a free-weight lifting environment, where there is a need for a system for gathering and interpreting exercise data, and where most professional and serious weightlifters are likely to concentrate their workout routines.

Free-weight exercise monitoring and feedback system and method


In accordance with the present invention, there are provided normal modified forms of nonsteroidal anti-inflammatory drugs. Modified NSAIDs according to the invention provide a new class of anti-inflammatory agent which provide the therapeutic benefits of NSAIDs while causing a much lower incidence of side-effects then typically observed with such agents.

Despite the advent of modem pharmaceutical technology, many drugs still possess untoward toxicities which often limit the therapeutic potential thereof. For example, although non-steroid anti-inflammatory drugs (NSAIDs) are a class of compounds which are widely used for the treatment of inflammation, pain and fever, NSAIDs (e.g., naproxen, aspirin, ibuprofen and ketoprofen) can cause gastrointestinal ulcers, a side-effect that remains the major limitation to the use of NSAIDs (see, for example, J. L. Wallace, in Gastroenterol. 112:1000-1016 (1997); A. H. Soll et al., in Ann Intern Med. 114:307-319 (1991); and J. Bjarnason et al., in Gastroenterol. 104:1832-1847 (1993)).
There are two major ulcerogenic effects of NSAIDs: (1) irritant effects on the epithelium of the gastrointestinal tract and (2) suppression of gastrointestinal prostaglandin synthesis. In recent years, numerous strategies have been attempted to design and develop new NSAIDs that reduce the damage to the gastrointestinal tract. These efforts, however, have largely been unsuccessful. For example, enteric coating or slow-release formulations designed to reduce the topical irritant properties of NSAIDs have been shown to be ineffective in terms of reducing the incidence of clinically significant side effects, including perforation and bleeding (see, for example, D. Y. Graham et al., in Clin. Pharmacol. Ther. 38:65-70 (1985); and J. L. Carson, et al., in Arch. Intern. Med., 147:1054-1059 (1987)).
It is well recognized that aspirin and other NSAIDs exert their pharmacological effects through the non-selective inhibition of cyclooxygenase (COX) enzymes, thereby blocking prostaglandin synthesis (see, for example, J. R. Van in Nature, 231:232-235 (1971)). There are two types of COX enzymes, namely COX-1 and COX-2. COX-1 is expressed constitutively in many tissues, including the stomach, kidney, and platelets, whereas COX-2 is expressed only at the site of inflammation (see, for example, S. Kragan et al. in Gastroenterol., 111:445-454 (1996)). The prostagladins derived from COX-1 are responsible for many of the physiological effects, including maintenance of gastric mucosal integrity.
Many attempts have been made to develop NSAIDs that only inhibit COX-2, without impacting the activity of COX-1 (see, for example, J. A. Mitchell et al., in Proc. Natl. Acad. Sci. USA 90:11693-11697 (1993); and E. A. Meade et al., in J. Biol. Chem., 268:6610-6614 (1993)). There are several NSAIDs presently on the market (e.g., rofecoxib and celecoxib) that show marked selectivity for COX-2 (see, for example, E. A. Meade, supra.; K. Glaser et al., in Eur. J. Pharmacol. 281:107-111 ((1995) and Kaplan-Machlis, B., and Klostermeyer, BS in Ann Pharmacother. 33:979-88, (1999)). These drugs appear to have reduced gastrointestinal toxicity relative to other NSAIDs on the market.
On the basis of encouraging clinical as well as experimental data, the development of highly selective COX-2 inhibitors appears to be a sound strategy to develop a new generation of anti-inflammatory drugs. However, the physiological functions of COX-1 and COX-2 are not always well defined. Thus, there is a possibility that prostagladins produced as a result of COX-1 expression may also contribute to inflammation, pain and fever. On the other hand, prostagladins produced by COX-2 have been shown to play important physiological functions, including the initiation and maintenance of labor and in the regulation of bone resorption (see, for example, D. M. Slater et al., in Am. J. Obstet. Gynecol., 172:77-82 (1995); and Y. Onoe et al., in J. Immunol. 156:758-764 (1996)), thus inhibition of this pathway may not always be beneficial. Considering these points, highly selective COX-2 inhibitors may produce additional side effects above and beyond those observed with standard NSAIDs, therefore such inhibitors may not be highly desirable.
Accordingly, there is still a need in the art for modified forms of NSAIDs which cause a reduced incidence of side-effects, relative to the incidence of side-effects caused by such pharmacologically active agents in unmodified form.

Protected forms of pharmacologically active agents and uses thereof


The present disclosure describes systems and techniques relating to generating three dimensional (3D) models from range sensor data. According to an aspect, 3D point clouds are captured using a 3D camera, where each of the 3D point clouds corresponds to a different relative position of the 3D camera with respect to a body. One of the 3D point clouds can be set as a reference point cloud, and transforms can be determined for coordinates of the other captured 3D point clouds to transform these to coordinates of the reference point cloud. The body represented in the reference point cloud can be segmented into body parts corresponding to elements of a 3D part-based volumetric model including cylindrical representations, and a segmented representation of the physical object of interest can be generated in accordance with the 3D part-based volumetric model, while taking localized articulated motion into account.

The present disclosure describes systems and techniques relating to generating three dimensional models from range sensor data, for example, performing three dimensional modeling in the presence of motion.
Three dimensional modeling from range sensor information is an active field. Many advances have been made in using software to build complex three dimensional models using range sensor information. For example, U.S. Pat. No. 7,583,275 to Newmann et al. describes generating a three dimensional model of an environment from range sensor information representing a height field for the environment. In addition, much work has gone into face recognition and reconstruction. For example, U.S. Pat. No. 7,856,125 to Medioni et al. describes a three dimensional face reconstruction technique using two dimensional images, such as photographs of a face. Other approaches for three dimensional modeling using images include those described in U.S. Pat. No. 7,224,357 to Chen et al.

3D body modeling, from a single or multiple 3D cameras, in the presence of motion


A medicine holder encloses one or more medicines which are in their original labeled containers, and emits an alarm signal when each dose is due. The alarm is automatically silenced when the holder is opened to retrieve the medicine. The timer is then automatically restarted when the holder is closed. The dose regimen is determined by an easily-operated selector switch, and is visibly displayed.

The invention relates to medicine timers, and more particularly to medication-holding enclosures with automatic timer means and alarm means.
Most medicines must be taken on a periodic schedule or dose regimen to obtain maximal effectiveness and safety. Many people find it difficult to follow a dose regimen, even with the best intent, due to distractions or disability or just being busy. This leads to missed or doubled doses, with potentially serious consequences. A wide assortment of medication holders and timers have been developed to remind people when a dose is due. However, all prior products fail to provide the combination of security and ease-of-use required for broad acceptance. The prior art medicine holders and timers can be categorized in four types, depending on the functions they perform for the patient:
Prior art medicine timers of type 1 are simply interval timers with an alarm function that alerts the patient when a dose is due (such as U.S. Pat. No. 7,330,101 to Sekura). Type 1 products fail to contain or identify the medication itself, and this leads to medicine mix-ups. Also there is no way for the timer to be reset automatically, by the act of medication-taking, and this causes further dose errors. For example, U.S. Pat. No. 7,054,231 to Valerio, U.S. Pat. No. 5,953,288 to Chappell, and U.S. Pat. No. 4,361,408 to Wirtschafter describe timers attachable to a pill bottle, but these fail to reset automatically when the medicine is taken.
Prior art of type 2 is a pill-carrier with timer means (such as U.S. Pat. No. 7,100,793 to Baum, U.S. Pat. No. 6,574,165 to Sharma, U.S. Pat. No. 6,449,218 to Lluch, U.S. Pat. No. 6,314,384 to Goetz, U.S. Pat. No. 6,169,707 to Newland, U.S. Pat. No. 5,915,558 to Girvetz, or U.S. Pat. No. 5,990,782 to Lee). Type 2 products hold the medicine or medicines, and provide a timed alarm. The products may also feature automatic restarting of the timer when the unit is opened. However, all type 2 medicine timers require that the medication be physically separated from the original labeled container that identifies the medicine. This is a major fault, potentially leading to medication mix-ups since many pills look similar. Also, there is no way to tell if a pill is outdated, such as a leftover medication still in the carrier from a previous prescription. Expired medication, although visually indistinguishable from the new medication, is potentially harmful. For these reasons, most people rely on a label to identify the medication and to provide a dispensing or expiration date to avoid such dosing errors. Therefore it is important to keep the medicine together with the original labeled container.
Prior art type 3 is a timer cap (such as U.S. Pat. No. 7,408,843 to Brandon, U.S. Pat. No. 7,382,692 to Hildebrandt, or U.S. Pat. No. 7,362,660 to Hildebrandt, or U.S. Pat. No. 6,859,136 to Gastel) that fits on the original labeled medicine container. The timer cap may be an add-on, or it may be a replacement for the original container cap. The product emits an alarm when each dose is due. The alarm is silenced, and the timer re-started automatically, when the cap is removed. Since the identifying label remains with the medication, type 3 products avoid the problem of medicine mis-identification discussed above. Unfortunately, type 3 products are useless for liquids and ointments that interfere with the timer circuit. Also, the type 3 products are so small it is difficult or impossible to change the timer battery; hence the product is normally thrown away as soon as the battery runs out. Also, it is difficult to select the timing interval since there is no room for a selection control such a knob. To set the dose time interval, type 3 products require the user to perform a complex series of steps, generally necessitating careful study of an instruction manual.
Another problem with the timer cap product is that it fits only one size of medicine container. Often the original container is incompatible with the timer cap, and so the medicine must be put into another container that fits the cap. This separates the medication from the identifying label, which defeats the purpose of keeping the medicine and its label together.
Prior art type 4 products are complex dispenser machines (such as U.S. Pat. No. 7,302,311 to Varts, U.S. Pat. No. 6,961,285 to Niemiec, U.S. Pat. No. 6,259,654 to de la Huerga, U.S. Pat. No. 5,838,224 to Andrews, U.S. Pat. No. 5,706,257 to Rothman, U.S. Pat. No. 5,289,157 to Rudick, or U.S. Pat. No. 4,275,384 to Hicks). Such products hold single or multiple medicines and are programmed to dispense or release each medication according to a schedule. Such machines are bulky and expensive, and are difficult to program. Some of these devices require separation of the medications from pharmacist containers or modifications to the pharmacist container for operation. Dispensing machines are notoriously prone to jamming, even when a single pill becomes broken during dispensing. Most people want to control their medications themselves and are reluctant to take a pill that some kind of machine simply dumps out.
What is needed is a simple and convenient medicine enclosure that accommodates medicine in its original labeled container, the medicine being in pill form or liquid form or ointment or any other form of medicine, while providing a fully automatic timed alarm to indicate when each dose is due, according to an easily-selected dose regimen. Here "easily" means that the user must be able to select the dose interval intuitively and without consulting a manual. Just for comparison, a toaster that has a single "light-medium-dark" switch is easy to set, whereas the clock on a VCR is not. Essentially all prior art medicine timers are difficult to set by this criterion. They involve multiple, non-intuitive steps that must be carried out in the right order, and are not user-friendly in any sense of the term.


An operator's station structure for a work vehicle having a motor section, comprising: a seat that is disposed on the operator's station for a work vehicle and has a moveable seat part; and a removable storage box that is disposed below the seat, that has an upwardly opening shape, and that has an interior accessible by moving the seat part.

1. Field of the Invention
The present invention relates to an operator's station structure for a work vehicle.
2. Description of the Related Art
In conventional work vehicles, a structure such as that disclosed in JP 2005-212783 is employed in which a plate-metal shielding cover is mounted on a vehicle body frame and a seat is disposed on the shielding cover.
A storage box into which small items are placed is preferably provided to the operator's station. The storage box is generally provided below the seat or on a dashboard at a front part of the operator's station. When the storage box is provided below the seat, a pullout-type storage box can be provided in a structure such as that described above in which the shielding cover is disposed below the seat. However, a slide-guiding structure must be employed so that the storage box can readily be pulled out and pushed in, which increases costs.

Operator's station structure for work vehicle


A home fuel gas refining system has a modifier for modifying a hydrogen-containing fuel to produce a modified gas. The modifier includes a hydrogen-containing fuel supply mechanism for supplying the hydrogen-containing fuel and a modifying air supply mechanism for supplying modifying air. The hydrogen-containing fuel delivered from the hydrogen-containing fuel supply mechanism and the modifying air delivered from the modifying air supply mechanism are mixed with each other by a modification fuel ejector, and then delivered to a reactor.

1. Field of the Invention
The present invention relates to a fuel gas manufacturing apparatus having a modifier for modifying a hydrogen-containing fuel which contains hydrocarbon, alcohol, or the like to produce a modified gas.
2. Description of the Related Art
There has been employed in the art a hydrogen manufacturing apparatus (fuel gas manufacturing apparatus) for modifying a hydrocarbon fuel such as natural gas or the like or a hydrogen-containing fuel containing alcohol such as methanol or the like to produce a hydrogen-containing gas (modified gas) and supplying the hydrogen-containing gas as a fuel gas to a fuel cell or the like.
Such a hydrogen manufacturing apparatus basically operates to modify a hydrocarbon fuel such as an LPG (liquefied petroleum gas), a city gas, or the like with water vapor to produce a hydrogen-containing gas as a high-concentration hydrogen-rich gas, and separate high-purity hydrogen from the hydrogen-containing gas with a PSA (Pressure Swing Adsorption) device according to pressure adsorption.
For example, Japanese Laid-Open Patent Publication No. 2002-201478 discloses a method of manufacturing hydrogen by mixing desulfurized kerosene and water vapor to vaporize the kerosene, and modifying the mixture of the vaporized kerosene and water vapor. According to the disclosed method, as shown in FIG. 8 of the accompanying drawings, kerosene stored in a kerosene tank 1 is delivered by a kerosene pump 2 to a desulfurizer 3. The kerosene is desulfurized by the desulfurizer 3 and then delivered as an ejector 4 which serves as a vaporizer. Water stored in a water tank 5 is delivered by a water pump 6 to a water vapor generator 7, which converts the water into water vapor that is delivered to the ejector 4.
The ejector 4 mixes the desulfurized kerosene with the water vapor to vaporize the kerosene, and delivers the mixture to a modifier 8. The modifier 8 modifies the mixture to extract hydrogen therefrom. The hydrogen is then delivered from the modifier 8 as fuel cell hydrogen to a fuel cell system (not shown).
In the conventional system shown in FIG. 8, the dedicated kerosene pump 2 is connected to the kerosene tank 1, and the dedicated water pump 6 is connected to the water tank 5. Therefore, the overall system is large in size and is not economical.

This patent is subject to a terminal disclaimer.


A sport footwear includes at least an upper part configured to act as an upper cuff and a lower part acting as a lower shell. The upper part has a pair of opposite and distanced lateral edges. At least one terminal closing mechanism is provided on the lateral edges and at least one other closing mechanism, positioned adjacent to the terminal closing mechanism, which extend frontally astride the lateral edges. The sport footwear includes a single command mechanism configured to drive both of the closing mechanisms at the same time. The command mechanism includes at least one main lever pivoted on a first of the lateral edges. Moreover, the closing mechanisms are each provided with a respective drive end connected to the main lever, near the first of the lateral edges, and with an opposite anchoring end connected to a second of the lateral edges.

Sport footwear is known, such as ski boots, snowboard boots, trekking boots or other similar sport footwear, which can be provided with an upper part, or cuff, and a lower part, or shell.
These known boots can assume a first clamped position, or position of use, to clamp the ankle and shin zone during sporting activity, and a second, released or loosened position to facilitate the user in putting on and removing the boot, and in walking.
The shell includes a front tongue, to cover a front opening near the shin zone of the user's leg, which is generally bent and/or moved forward to facilitate the removal/insertion of the foot from/into the boot.
Sport boots are also known in which the opening is defined by distancing and separating lateral portions of the shell which normally overlap in correspondence with the shin zone.
Associated with the front part of the sport boot there are normally one or more closing mechanisms which allow to selectively regulate the intensity of closure of the main structure of the boot, to clamp the latter with respect to the foot and the shin zone of the user's leg.
Known sport boots are also generally provided with other closing mechanisms attached to the shell and/or the upper cuff, which selectively allow to clamp the ski boot in the upper part thereof, for use during sporting activity, or to release it so that it can be put on or removed.
To this purpose different types of closing mechanisms are known, which can include, for example, an attachment member with teeth, with which a closing lever engages, or a screw-type regulator, both configured to tighten the front part of the sport boot by bringing together two opposite sides of the lateral portions. The closing or tightening force can be regulated and selected by the user according to his/her own requirements.
A subsequent opening of the closing mechanisms allows to loosen the sport boot, so as to allow the user to remove it at the end of his/her sporting activity, or to facilitate walking during a pause in the activity.
Known closing mechanisms have the disadvantage, however, that they normally consist of complex and bulky mechanisms that entail an increased complexity in maneuvering for the user.
Among the types of closing mechanisms with which a sport boot is provided there is also a Velcro® strip, typically positioned in the upper part of the front or shin zone of the sport boot, and attached in the external part of the upper cuff.
To clamp the sport boot it is provided to insert the Velcro® strip inside an eyelet on a lateral part of the upper cuff.
The Velcro® strip is then returned toward the opposite side of the upper cuff and adjusted according to the user's requirements.
One disadvantage of known sport boots is that it is very inconvenient to adjust the closing mechanisms, especially the type with teeth attachment, which are very difficult to adjust with respect to the Velcro® strip.
During pauses or rest-stops in the sporting activity, or for example during an ascent or while walking, it is possible to open the closing mechanisms in the upper part of the sport boot, that is, the Velcro® strip and the first closing clip, to allow better use of the sport boot while walking.
Another disadvantage is that, when the user again needs to clamp the sport boot after the pause or rest-stop, he/she will not always be able to obtain the same adjustment as desired and set at the start of the day.
Moreover, the operation to clamp a known sport boot can occupy the user for a long time because, during use, the user will be wearing gloves, which limit the mobility of the user's hands.
Furthermore, during the operation to clamp a sport boot during use, the user is generally precariously balanced, for example on the snow, on a slippery and/or icy surface, often on a slope, which conditions are potentially dangerous.
Another obstacle to manipulating known closing mechanisms is that generally they are positioned under the user's trouser-legs, and he/she is therefore obstructed in driving the levers of the mechanisms.
German Patent 69301215 describes a ski boot that provides a shell, a upper cuff articulated on the shell and an inner boot. The upper cuff is in turn formed by two parts that are articulated with respect to each other, a front part and a rear part, which are reciprocally brought together and kept clamped by a closing system of levers. Moreover, a strip system is provided to tighten the inner boot.
Swiss patent application publication CH 688,606 A also describes a clamping device for a ski boot, including a shell and a upper cuff consisting of a front part and a rear part clamped to each other by a closing system of levers.
Swiss patent application publication CH 471 553 A describes another ski boot of a known type, provided with a single closing system with a connection clip.
European patent application publication EP 2 591 696 A describes another ski boot of a known type, provided with a single closing system including a connection cable.
There is therefore a need to perfect sport footwear, such as a ski boot or other similar footwear, that can overcome at least one of the disadvantages of the state of the art.


A memory system and a method for operating the same are provided. The memory system includes a semiconductor memory device suitable for performing an erase operation in response to a control signal, and if an erase command is input from a host, a controller suitable for temporarily storing erase block information according the erase command, and when a program command is input after the erase command is input, transmitting the control signal according to the erase command to the semiconductor memory device.

1. Technical Field
Various embodiments of the present invention relate to an electronic device, and more specifically, to a memory system and a method for operating the same.
2. Related Art
Semiconductor memory devices are mainly categorized into volatile memory devices and non-volatile memory devices.
The volatile memory device is fast during write and read operations, but when power is interrupted stored data is lost. The non-volatile memory device is slow performing write and read operations when compared to the volatile memory device, but it retains its data even when power is interrupted. Therefore, the non-volatile memory device is used to store data required to be retained regardless of whether or not power is on. Examples of the non-volatile memory device include a read only memory (ROM), a mask ROM (MROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a flash memory, a phase-change RAM (PRAM), a magnetic RAM (MRAM), a resistive RAM (RRAM), a ferroelectric RAM (FRAM) etc. The flash memory is divided into a NOR type flash memory and a NAND type flash memory.
The flash memory has the strengths of the RAM, easy programming and erasing data, as well as the strengths of the ROM, retaining stored data when power is interrupted. The flash memory is used as a storage medium for portable electronic devices, such as digital cameras, personal digital assistants (PDA), and MP3 players.
When an erase command is input from a user, the flash memory may instantly perform an erase operation. Alternatively, when an erase command is input while the flash memory is performing another operation, the flash memory performs an erase operation after completing the other operation. Thereafter, when a program command is input from the user, a program operation is performed on the memory block having the completed erase operation.
After completion of the erase operation, if the program operation takes a long time then the retention characteristics of the memory cells included in a memory block during an erase state are lowered so that threshold voltages are shifted upward, and thus the erase distribution characteristics may be degraded.

Memory system and method for operating the same


The present invention can suppress variations in dispersion and grinding processing, apply stable shearing force to a material to be processed, and also enable efficient dispersion and grinding. The present invention has a supply portion (10A), a processing portion (10B), and a discharge portion (10C). The processing portion (10B) includes a stator (12b), and a rotor (11b). The material to be processed is processed in a gap (Gt) between an outer peripheral surface of the rotor (11b) and an inner peripheral surface of the stator (12b). The inner peripheral surface of the stator (12b) and the outer peripheral surface of the rotor (11b) are circular in a cross section orthogonally intersecting the axis of the rotor (11b) and linear in a cross section bearing the axis. The gap (Gt) is constant in the circumferential direction and the axial direction.

Various types of dispersion machines have been developed as the above-mentioned machines for performing dispersion or grinding processing. Among such dispersion machines, there is a colloid mill-type dispersion machine.
This dispersion machine includes a pair of upper and lower disk-shaped grindstones, and the upper and lower grindstones are relatively rotated with their axes aligning with each other. The granular material (material to be processed) that is supplied to a central charging part is thereby atomized in the course of being discharged to the outer periphery through a gap between the grindstones (for example, refer to Japanese Unexamined Patent Publication No. 2000-153167).
Meanwhile, with the dispersion machine of Japanese Unexamined Patent Publication No. 2000-153167, since the peripheral velocity at a portion near the axis of the grindstone is different from the peripheral velocity at a portion near the periphery in the gap between the grindstones, the shearing force applied to the material to be processed is smaller at the portion near the axis than at the portion near the periphery. Accordingly, since the material to be processed moves in a shearing force distribution having a gradient of shearing force, a difference in the shearing force that is applied to the material to be processed will arise depending on positions where the material to be processed moves, which causes a problem that variations tend to arise in the dispersion processing.
Moreover, with the dispersion machine of Japanese Unexamined Patent Publication No. 2000-153167, since there is a considerably great gradient in the shearing force distribution in the gap (dispersion region) between the upper and lower grindstones, it is difficult to apply a relatively stable shearing force to the material to be processed. In particular, there is a problem that a sufficient shearing force cannot be applied at a portion near the axis of the grindstones in the gap. In addition, with the dispersion machine of, a lower surface of the upper grindstone and an upper surface of the lower grindstone are not flat and are formed at a predetermined inclination. Thus, since the gap between both grindstones will change in the circumferential direction and the radial direction, the material to be processed in the form of a fluid existing in the gap will be seen to have changed viscosities in view of Newton's well-known viscosity equation, which causes a problem that dispersion cannot be performed efficiently.
The dispersion machine of Japanese Unexamined Patent Publication No. 2000-153167 will encounter the same situation when used for grinding a solid.


A power supply includes a casing mounted in a computer housing, a power module disposed in the casing, and an electrical socket and a switch module embedded in an exposed side wall of the casing. The switch module includes an operating unit mounted movably in a mounting seat, and operable so as to move among a first position adjacent to the side wall, where two terminal units coupled respectively to the electrical socket and the power module disconnect electrically from each other such that the switch module is in an OFF mode, a second position distal from the side wall, and a third position between the first and second positions, where a conducting member contacts electrically the terminal units such that the switch module is in an ON mode. When the switch module is switched from the ON mode to the OFF mode, the operating unit is moved from the third position to the first position via the second position.

1. Field of the Invention
The invention relates to a power supply, more particularly to a power supply for a computer device.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a conventional power supply 1 for a computer device is shown to include a casing 10, a power module 14, an electrical socket 15, a switch unit 16, and a fan module 13. The casing 10 is adapted to be mounted in a computer housing (not shown) of the computer device, and includes complementary upper and lower casing parts 11, 12 configured with an inner receiving space therebetween, as shown in FIG. 2. The power module 14 is disposed in the inner receiving space and is coupled to the fan module 13. The electrical socket 15 is embedded in an exposed side wall 121 of the lower casing part 12, and is adapted to be coupled to an external power source (not shown), such as a commercial power source, via a cord. The switch unit 16 is mounted to the side wall 121 of the lower casing part 12, and interconnects electrically the electrical socket 15 and the power module 14. The switch unit 16 is operable between an OFF mode, where the electrical socket 15 is not connected electrically to the power module 14, and an ON mode, where the electrical socket 15 is connected electrically to the power module 14 such that the power module 14 receives electric power from the external power source via the cord and the electrical socket 15, and processes the electrical power so as to supply an electric power to the fan unit 13 and the computer device.
It is noted that the switch unit 16 includes an inclined operating key 161. The switch unit 16 is switched from one of the ON and OFF modes to the other one of the ON and OFF modes by pressing the operating key 161. Since the operating key 161 projects outwardly from the side wall 121, unintentional operation of the operating key 161 easily occurs.


Provided are: a prepolymer which is capable of forming a non-linear optical material that has excellent non-linear optical effect, heat resistance, withstand voltage and transparency; a curable material which contains the prepolymer; a coating composition which contains the curable material and a solvent; a non-linear optical material which is obtained by curing the curable material; an optical waveguide which uses the non-linear optical material; and a light control device which is provided with the optical waveguide. The present invention uses a prepolymer having a crosslinkable functional group, which is obtained by reacting one or more compounds (X) that are selected from the group consisting of compounds (X1), compounds (X2) and compounds (X3), a compound (Y) that is represented by formula (Y), a compound (Z) that has three or more phenolic hydroxyl groups, and an organic compound (B) that exerts a non-linear optical effect and has a reactive group.

As a light control device utilizing a nonlinear optical effect, an optical modulator, an optical switch, etc. have been known. The nonlinear optical effect is a phenomenon showing a nonlinear relation between the electric polarization caused when a strong electric field (optical electric field) is applied to a substance, and the electric field applied. A nonlinear optical material is a material which remarkably shows such nonlinearity.
As a nonlinear optical material utilizing a quadratic nonlinear response, a material which causes second harmonic generation (SHG) or a material which causes Pockels effect (linear electro-optic effect) which produces a change in the refractive index proportionally to the electric field, i.e. an electro-optic effect (EO effect) and the like have been known.
As a nonlinear optical material to be used for the light control device, a nonlinear optical material (a so-called electro-optic polymer) in which an organic compound which develops a nonlinear optical effect is dispersed and oriented by an electric field orientation treatment in a matrix of an organic polymer, has attracted attention in view of easiness of a process for producing a light control device, and easiness of an increase in the area.
The nonlinear optical material is required to have the following properties (i) to (iv).
(i) It is excellent in the nonlinear optical effect.
(ii) The glass transition temperature (Tg) of its matrix is sufficiently high, that is, it is a material excellent in the heat resistance, since if Tg of the matrix is low, orientation of an organic compound to develop a nonlinear optical effect, which is forcibly oriented, is relaxed, and the nonlinear optical effect will be decreased.
(iii) When an organic compound to develop a nonlinear optical effect is oriented in the matrix by electric field orientation treatment, the material is more excellent in the nonlinear optical effect as the voltage applied is higher. If the dielectric voltage of the material is low, short circuiting will occur at the time of the electric field orientation treatment. Thus, the nonlinear optical material is a material having a high dielectric voltage.
(iv) It is excellent in the transparency at a wavelength used (1.3 μm band or 1.5 μm band), in view of small optical transmission loss.
Heretofore, a host-guest nonlinear optical material has been developed, since its material is easily available and it is easily produced. A host-guest nonlinear optical material may be produced by dispersing a compound (guest) having nonlinear optical properties in an optically transparent matrix (host). As the matrix, a polymethacrylate (PMMA) has been actively studied.
However, in a host-guest nonlinear optical material, guest molecules are merely dispersed and there is no bond nor interaction with the matrix, whereby orientation of the guest molecules is thermally unstable and is easily relaxed (Non-Patent Document 1).
Accordingly, it has been studied to suppress relaxation of orientation by bonding the guest molecules to the matrix to limit free movement of the guest molecules. For example, it has been studies to bond the guest molecules to PMMA by a covalent bond (Patent Document 1).
However, the nonlinear optical material the matrix of which is PMMA has a substantial problem such that if it is left to stand at a temperature less than about 100° C. after the electric field orientation treatment, the quadratic nonlinear response will be impaired (FIG. 2 in Non-Patent Document 2, FIG. 4 in Non-Patent Document 3, FIG. 3 in Non-Patent Document 4, FIG. 2 in Non-Patent Document 5). Further, since Tg of PMMA is so low as about 100° C., the process temperature after the electric field orientation treatment is limited to be less than about 100° C. The nonlinear optical material the matrix of which is PMMA has an insufficient dielectric voltage. Further, since PMMA has many C—H bonds, its transparency in 1.3 μm band and 1.5 μm band is insufficient.
As a nonlinear optical material of which the orientation relaxation is suppressed, a nonlinear optical material having a structure to develop a nonlinear optical effect in side chains of a polyimide having high heat resistance has been proposed (Non-Patent Document 6). Further, a nonlinear optical material having crosslinks by Diels-Alder reaction introduced to the matrix has been proposed (Non-Patent Documents 7 and 8).
As a nonlinear optical material which is highly transparent in 1.3 μm band and 1.5 μm band, a material the matrix of which is made of an amorphous fluorinated polymer has been proposed (Patent Document 2).
A nonlinear optical material having a structure to develop a nonlinear optical effect in side chains of a matrix containing fluorine has been proposed (Non-Patent Document 9).

Prepolymer, curable material, coating composition, non-linear optical material, optical waveguide and light control device


A package having a three dimensional shape and a plurality of modules each being adapted to contain a plurality of feminine hygiene articles. The plurality of modules can include a first end module, a second end module, and one or more middle modules. The first end module and the second end module each can have a free edge and a linked edge, and the one or more middle modules can have a first linked edge and a second linked edge. The linked edge of the first end module can be connected to the first linked edge of a middle module, the one or more middle modules can be connected together at the first and second linked edges, and the linked edge of the second end module can be connected to the second linked edge of a middle module to form a chain of modules. The plurality of modules can be arranged to form the package three dimensional shape.

Feminine hygiene articles can include absorbent articles, such as, e.g. sanitary napkins, liners, tampons, interlabial products, and incontinence articles, as well as other articles such as, e.g. wipes or powder. These articles are often carried and/or stored by a user in her purse, bag, pocket, or the like. Generally, feminine hygiene articles can be individually wrapped to facilitate ease of carrying and storage. These wrappers tend to degrade, rip, and/or break over time when carried in a purse or bag, however, after which the feminine hygiene article may need to be discarded.
A user may wish to carry multiple feminine hygiene articles in her purse or bag, such as, e.g., an amount sufficient for a day or for several days, such as, e.g., over the course of a menstrual period. In order to accomplish this goal, a user may transfer the desired number of individually wrapped feminine hygiene articles from the retail package into her purse or bag. These articles may become dispersed throughout her purse or bag such that they are difficult to find. In addition, such articles may be easily recognized as feminine hygiene articles, which can be undesirable to a user. As such, some users can carry feminine hygiene articles in discreet cases or pouches that can be reused. These reusable pouches, however, need to be refilled and may become worn or stained after extended use. Alternatively, some users may carry or store multiple feminine hygiene articles in the original retail packaging, which may be too large to facilitate ease of carrying and storage. Trial size retail packages can be purchased, although typically at a premium price, and multiple trial size packages must be purchased and handled to provide sufficient numbers of products for a typical menstrual cycle.
As such, it would be desirable to provide a package for feminine hygiene articles that can provide improved ease of carrying and storage.

Modular package for feminine hygiene articles


Disclosed are a ferrite carrier for electrophotographic developer and an electrophotographic developer using the ferrite carrier, wherein: the ferrite carrier is a composite ferrite composed of Li and Mg; when the composition of the ferrite is calculated as a mixture of a Li ferrite having a stoichiometric composition and a Mg ferrite having a stoichiometric composition, the excessive amount of Fe2O3 is less than 5 mol %, or the total excessive amount of Li2O and MgO is less than 1 mol %; the content of the elements other than Li, Mg, Fe and O is 2 % by weight or less; and further, the content of Mn in terms of element is 1000 to 9000 ppm.

A two-component developer used in electrophotography is composed of a toner and a carrier. The carrier is a substance which is mixed and stirred with the toner in a developer box to give a desired charge to the toner and carries the charged toner onto an electrostatic latent image formed on a photoreceptor to form a toner image. The carrier is held by a magnet so as to remain on the developing roller after the toner image formation, and is made to return to the developer box where it is again mixed and stirred with fresh toner particles for repeated use over a certain period.
In contrast to the one-component developer, the two-component developer contains the carrier which has the functions such that the carrier stirs toner particles to give a desired charge to the toner particles and carries the toner. As a result, the two-component developer is excellent in controllability in designing developers, and hence is widely used in the fields of full color machines required to provide high image qualities and high-speed machines required to secure reliability and durability in image maintenance.
In such a two-component electrophotographic developer, for the purpose of obtaining high-quality images, particles of ferrites such as Cu—Zn ferrite and Ni—Zn ferrite have been used as carriers in place of oxide-coated iron powders and resin-coated iron powders. As compared to conventional iron powder carriers, ferrite carriers using such ferrite particles as described above are generally spherical and have many advantageous properties for obtaining high quality images such that the magnetic properties thereof are controllable. Further, resin-coated ferrite carriers prepared by coating such ferrite particles used as the carrier cores with various resins are improved in abrasion resistance, durability and the like, and make the volume resistivity controllable.
However, the conventional ferrite carriers containing heavy metals such as Cu, Zn and Ni currently tend to be avoided from the viewpoint of reduction of the load on the environment, regulations of waste, and others. Additionally, such heavy metal-containing ferrite carriers tend to have lower electrical resistance leading to a problem such that image defects are caused by leakage under high electric field. Further, there have been problems that such heavy metal-containing ferrite carriers are heavy in specific gravity and hardly capable of attaining high durability.
On the other hand, for the purpose of solving the above-described problems, some light metal-containing ferrite carriers have been disclosed. For example, Japanese Patent Laid-Open No. 2001-154416 describes an electrophotographic carrier using a magnesium-containing ferrite; additionally, Japanese Patent Laid-Open No. 7-225497 discloses a ferrite carrier for electrophotographic developer using a lithium-containing ferrite and a developer using the carrier; further, Japanese Patent Laid-Open No. 7-333910 discloses a ferrite carrier for electrophotographic developer using a lithium-containing ferrite which is partially substituted with an alkali earth metal oxide (MgO, CaO, SrO or BaO) and a developer using the carrier.
However, these light metal-containing ferrite carriers suffers from a problem such that the magnetization variation and electrical resistance variation among particles tend to be generated, and accordingly tend to cause image defects such as carrier adhesion when used in electrophotographic developers. Specifically, as disclosed in Japanese Patent Laid-Open No. 2001-154416, a ferrite carrier containing only magnesium as a main component degrades the saturation magnetization. On the other hand, when the saturation magnetization is enhanced by developing a magnetite phase through excessively mixing iron oxide and sintering in a reductive atmosphere, the electrical resistance is drastically decreased to induce carrier adhesion.
Additionally, as disclosed in Japanese Patent Laid-Open No. 7-225497, a ferrite carrier containing a large amount of lithium tends to give a large magnetization variation among particles.
Japanese Patent Laid-Open No. 7-333910 discloses a carrier for electrophotographic developer excellent in image quality and durability, benign to the environment, long in life and excellent in environmental stability, wherein the carrier is prepared by substituting part of Li2O and/or Fe2O3 in a lithium-containing ferrite with an alkali earth metal oxide such as MgO, CaO, SrO or BaO. However, such substitution creates a part to be a hard ferrite substituted with CaO, SrO or BaO, and consequently the remanent magnetization and the coercive force are increased to degrade the fluidity, and the surface property variation tends to be generated.
Additionally, in Example 2 and Example 3 in Japanese Patent Laid-Open No. 7-333910, examples of composite ferrites containing Li and Mg. As described below, lithium is a monovalent metal and Mg is a divalent metal, and hence the Li ferrite is present in a form of (Li2O) (Fe2O3)5 and the Mg ferrite is present in a form of (MgO) (Fe2O3); accordingly, in the ferrite of above Example 2, it is assessed that (Fe2O3) is present in excess by approximately 7 mol %.
Similarly, the composition of above Example 3 is assessed to contain (Li2O) in excess by approximately 1.9 mol %, or (Li2O) and (MgO) in excess by approximately 5.7 mol % in total.
Further, Japanese Patent Laid-Open No. 7-333910 discloses an example (Comparative Example 20) in which Mn is contained in a Li-containing ferrite; however, as shown in the evaluation results of Japanese Patent Laid-Open No. 7-333910, the scattered amount is abnormally large, so that such a ferrite is far from a practically usable level. However, in contrast to the present invention, Japanese Patent Laid-Open No. 7-333910 does not present any disclosure or suggestion with respect to the effect and the appropriate content range of Mn contained in a trace amount.
An attempt to solve the above-described problems has been made by containing a trace amount of a heavy metal element in these light metal-containing ferrite carriers. Japanese Patent Laid-Open No. 2006-154806 describes a carrier having a coating layer and a carrier core containing 10 to 40 mol % of a metal oxide containing at least one metal element selected from the group consisting of magnesium, lithium and calcium and containing 50 to 4000 ppm, in terms of the total sum, of a metal oxide containing at least one metal element selected from the group consisting of manganese, copper, chromium and zinc.
However, even by controlling the elements, described in Japanese Patent Laid-Open No. 2006-154806, used in wide ranges and the contents thereof, and the contents of trace components, the carriers thus obtained hardly fulfill the high-level requirements in the image formation using recent electrophotography. In Examples of Japanese Patent Laid-Open No. 2006-154806, the "carrier 1," "carrier 13," "carrier 14," and "carrier 20" are disclosed as the carriers using the "carrier core 1." As can be seen from the results obtained for Examples and Comparative Examples using these carriers, no sufficient properties can be obtained depending on the fine particles contained in the coating resin even by using the carrier core materials evaluated to have sufficiently satisfactory compositions in Japanese Patent Laid-Open No. 2006-154806.
For example, the "carrier core 1" in Japanese Patent Laid-Open No. 2006-154806 is a ferrite containing Li and Mg as main components and is described to be composed of LiO: 12.9 mol %, MgO: 6.5 mol % and Fe2O3: 80.6 mol %. As described above, lithium is a monovalent metal and Mg is a divalent metal, and hence the Li ferrite is present in a form of (Li2O) (Fe2O3)5 and the Mg ferrite is present in a form of (MgO) (Fe2O3); accordingly, even if LiO (divalent Li) is used to give the above described composition, it is assessed that (Fe2O3) is present in excess by approximately 42 mol %.
Similarly, the "carrier core 3" in Japanese Patent Laid-Open No. 2006-154806 leads to an assessment that (Li2O) is contained in excess by 6 mol %, or (Li2O) and (MgO) are contained in excess by 15 mol % in total.
Such ferrites largely deviating from the stoichiometric compositions are hardly controllable in electrical resistance, and tend to undergo generation of the magnetic property variation and the surface property variation among particles, and hence, even by controlling other trace components, no sufficient properties can be obtained.
According to the description on p. 177 of "Iron Oxide for Ferrite (Ferrite You Sanka Tetsu, in Japanese)" by Toshiro Sumita, pp. 175 to 177, the manganese contents of the JIS first to third types of iron oxide are 0.30% by weight or less. Thus, the content of manganese as a concomitant impurity in the generally commercially available iron oxide can be found to be 3000 ppm or less.
Recently, in two-component electrophotographic developers, acceleration of the development performance and full-color development are strongly required. Among such requirements, higher durability and higher reliability are demanded, and no generation of image defects is also demanded.
Examples of the factors for improving the durability of electrophotographic developers include the light specific gravity of the carrier. Additionally, for the purpose of attaining high reliability, small variations among carrier particles are required for various properties such as the electrical resistance properties, magnetic properties and surface property. For the purpose of preventing the generation of image defects, it is required that the carrier be high in electrical resistance and no leakage be generated even in a high electric field. None of the ferrite carriers described in the above-described patent documents meets these requirements.

Ferrite carrier for electrophotographic developer and electrophotographic developer


Optical pickup 24 for operation in the far-field and in the near-field mode comprising a movable part 26 having an objective lens 2 comprising a solid immersion lens 4 and a multifocal lens 6, which are both disposed on a common optical axis A. The multifocal lens 6 comprises a central zone 8 and a peripheral zone 10 being circumferential to the central zone 8. The peripheral zone is adapted to constitute an optical system for a far-field mode. The central zone 8 of the multifocal lens 6 together with the solid immersion lens 4 are adapted to constitute an optical system for a near-field mode. The solid immersion lens and the multifocal lens are adapted to be moved in unison. A method for operating an optical pickup 24 comprises a first approach to a surface 21 of an optical storage medium 22 with the movable part 26 to reach a far-field working distance DF based on a focus control using an optical system for working in the far-field mode, and a subsequent approach to the surface 21 of the optical storage medium 22 which is performed by lowering the far-field working distance DF to a smaller near-field working distance NF.

Nowadays information technology is confronted with an increasing amount of data, due to more complex or multimedia applications. Accordingly, removable data storage devices with a high storage capacity are needed, e.g. for high resolution movies or video games. Well at the beginning of information technology, magnetic storage devices were favored, while nowadays, optical storage media such as CD (Compact Disk), DVD (Digital Versatile Disk) or BD (Blu-Ray Disk) are dominating the market for removable data storage media.
Optical data storage is generally limited by the optical resolution of the read/write-system. Straightforward methods of increasing the optical resolution involve widening of the focused beam and opening angle, i.e. the numerical aperture NA, at the costs of lens complexity. Further approaches are narrowing the allowable tilt margins for the optical storage media or reducing the wavelength of the scanning laser into the blue or near-UV range. A different approach for reducing the focus spot size in an optical data storage system is using near-field optics with a high numerical aperture (NA>1). This high numerical aperture is generally achieved by help of a solid immersion lens (SIL). While conventional systems like CD, DVD or BD operate in the optical far-field regime, which is described by classical optics, the aforementioned new systems work in the optical near-field regime, which is described by near-field optics. For conventional systems the working distance, i.e. the air gap between the surface of the optical storage medium and the first optical surface of the read/write-head, usually the objective lens, is in the scale of 100 μm. In contrast, systems making use of near-field optics need a very small working distance or air gap, which is in the scale of 50 nm. An optical storage system for recording and/or reading making use of near-field optics is disclosed in WO 2005/104109 A1. The low working distance between the surface of the storage medium and the surface of the objective lens is one of the main challenges of near-field technology. The small working distance requires setting strict specifications on the tilt and vertical deviation limits for the related optical storage medium e.g. a disc. Even if the disc specifications only allow vertical run out values which are several times smaller than for a current Blu-Ray Discs, e.g. 20 μm instead of 100 μm, it is still difficult for the read/write-head of an optical pick up to approach the disc surface and close the focus loop without head-disc contact or head crash.
A straight forward approach is to start the read/write operation from a lead-in area where tilt and deviation are usually lower compared to outer areas of the storage medium. However, for a near-field optical storage system it is desirable to reach outer areas of the storage medium without continuous focus operation at the aforementioned low working distance of approx. 50 nm.
Also, JP 11-259897 discloses an optical pickup capable of recording and reproduction for both high-density and low-density optical recording media. The pickup has a first objective for low-density media, which converges collimated light, a light shield which cuts off part of the light passing through the first objective, and an optical element consisting of a second objective and a solid immersion lens for high-density media. For low-density media the head is put close to the light shield by a slider. For high-density media the head is put adjacent to the recording medium.
US 2008/0198728 discloses an optical disk drive comprising an objective lens, a solid immersion lens, and an aperture element for collecting a part of a light beam reflected by an optical recording medium, corresponding to the effective aperture number of the objective lens and the solid immersion lens of less than 1 A speed-generating circuit reduces a speed of approach of the solid immersion lens to the recording medium in accordance with the level of a signal detected by a detecting element. A driver circuit drives the objective lens and the solid immersion lens in accordance with the output from the speed-generating circuit. In this way it is assured that the solid immersion lens does not get into contact with the optical recording medium.
US 2008/0089208 discloses a near field optical scanning device, which is adapted to bring a lens from a remote position to a near field position relative to the surface of an optical recording medium. Image processing of aperture pupil images indicating the size of a gap between a solid immersion lens and the surface of the optical recording medium is used for this purpose. Image analysis of the aperture pupil image allows to derive a control signal for an approach procedure for air gap distances in a range of micrometers. This allows for a fast, efficient, accurate and reliable approach procedure.

Objective lens and optical pickup comprising the objective lens


A shared bus hang prevention and recovery scheme for a data communication system is provided, where a shared bus is connected to a plurality of bus masters and corresponding slaves and located between an external bus connected to a system processor, and an internal bus connected to an internal processor. Some of the masters are associated with the external bus and others are associated with the internal bus, and one of the bus masters is a control master associated with the internal processor. The scheme utilizes a shared bus hang prevention and recovery device having a circuitry and a control code. The circuitry is timing each pending request of the control master for the shared bus and initiating bus recovery if the shared bus is hung up, when the control master exceeded a pre-determined time period allowed for waiting to acquire the shared bus control and complete the transfer on the shared bus. The control code is used for monitoring and controlling the circuitry and terminating the transfer in progress causing the shared bus hang-up. During the bus recovery the circuitry prevents bus request grants to the master attached to the external bus until the master subsequent reset, and the control program instructions initiates transfers for all pending requests for the shared bus from the control master queue. Each transfer is being timed and terminated if the shared bus is hung up again. Upon the control master queue clearing, the internal processor executes the control program instructions to reset and reinitialize all masters and slaves on the shared bus.

1. Field of the Invention
The present invention generally relates to bus hang prevention operations, and more particularly, to a bus hang prevention and recovery system and method for use in a multi-master bus system.
2. Description of Related Art
Digital communication over a communication channel is well known in the art. Modem data communication systems often have multiple high performance data processors and generally include a plurality of external devices interconnected by one or more various buses. For example, modem computer systems typically include a system processor coupled through a high bandwidth local expansion bus, such as the peripheral component interconnect (PCI) bus or the VESA (Video Electronics Standard Association) VL bus, to an external shared memory, peripheral devices, and other processors. Examples of devices which can be coupled to local expansion buses include SCSI adapters, network interface cards, video adapters, etc.
High performance bus architectures, such as the PCI bus architecture, provide a hardware mechanism for transferring large sequential groups of data between a peripheral controller""s local memory and a system processor""s shared memory via burst cycles. In many bus architectures, the maximum burst length is typically not defined.
Systems in which many devices share a common resource, typically utilize arrangements for allocating access to the resource under conditions during which a plurality of associated devices may concurrently request access. High performance systems have the potential to generate multiple independent requests for access to one or more external components, often via a single shared bus interface unit (BIU). Since multiple independent input/output (I/O) requests may appear at the BIU at any given time, the data communication system requires a shared bus arbitration scheme to determine the priority of the I/O requests for accessing the shared bus. In multi-master systems, where one or more data processors have the capability of becoming a bus master, the bus arbitration protocol determines which data processor becomes the bus master first. Typically, these multi-master systems employ an arbiter, external to the data processors, to control the shared bus arbitration, and each data processor requests access to an external shared memory or another external device from the arbiter.
In typical microprocessor systems the bus transports data among the processor and other components. The central processing unit (CPU) is usually the master of the bus, controlling the flow of data to and from the CPU and to the other components of the system, such as printers, memory, displays, and parallel and serial ports. Rather than have the CPU perform complex mathematical calculations, which is very slow, the data may be sent to the dedicated math co-processor where the calculations are performed, freeing the CPU to perform another task. Other masters in a multi-master arrangement may be used for ethernet control as part of a local area network (LAN), video controllers, or some other customized operation.
In a multi-master communication system a shared bus may become hung-up for various reasons. For example, a hang condition could happen due to an unrecognized address on a shared bus, when the system cannot abort the transfer or does not have the ability to ban the bus master from the shared bus. Sometimes a bus master does not give up the shared bus for a long time, thus causing other masters to be unable to proceed with a transfer in time. Other times a condition happening elsewhere in the system makes buffer space or data unavailable for an unacceptable amount of time, so that the bus becomes unusable.
If a bus hang condition occurs on a shared bus within a subsystem of a communication system with several subsystems, so that a transfer operation cannot be completed, it is possible that the entire subsystem will not be able to proceed any further. The subsystem processor may itself be unable to proceed (e.g. is presently attempting to read an address via the hung shared bus) and therefore cannot be used to recover from the hang condition. If the subsystem hang condition must be reset from an external source (i.e., from the system""s main computer via a bus external to the subsystem), the loss of information on either transferring data and/or error conditions may occur. It may also result in the subsystem being unable to interact with other subsystems while the recovery is taking place and/or during the time it takes for the external source to realize that a problem has occurred in the subsystem. This may in turn require further recovery efforts to become necessary. In other conventional systems, the entire subsystem has to be reset, via an external source. This not only causes the loss of error/recovery information but may cause additional problems with any other subsystem of the communication system, with which the subsystem getting reset is interfacing.
Therefore, there is a need for an improved hang prevention and recovery system and method, usable in high performance multi-master data communication systems with multiple shared external devices. This system and method should be able to prevent a permanent bus hang condition and allow recovery of the subsystem to a known state, so that the propagation of problems to other subsystems, which may otherwise cause severe consequences, can be avoided.
The foregoing and other objects, features, and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments which makes reference to several drawing figures.
One preferred embodiment of the present invention is a shared bus hang prevention and recovery device usable in a multi-master data communication system. The system preferably has a plurality of bus masters and corresponding slaves. The hang prevention and recovery device is connected to a shared bus, and the shared bus is located between an external bus connected to a system processor, and an internal bus connected to an internal processor. Some masters are associated with the external bus and other masters are associated with the internal bus. One bus master on the internal bus is named a control master, associated with the internal processor.
The shared bus hang prevention and recovery device has a circuitry for timing each pending request of the control master for the shared bus, and control program instructions for monitoring and controlling the circuitry. The circuitry initiates bus recovery if the shared bus became hung up, when the control master exceeded a pre-determined time period allowed for waiting to acquire the shared bus control and complete the transfer on the shared bus. At the bus hung-up, the circuitry terminates the transfer in progress, causing the shared bus hang-up to be freed, and performs shared bus recovery. During the recovery the circuitry prevents bus request grants to the master attached to the external bus until the master is subsequently reset. Next, the circuitry initiates transfers for all pending requests for the shared bus from the control master queue, where each transfer is timed and terminated if the shared bus became hung up again. Upon the control master queue clearing, the control program instructions instruct the circuitry to reset and reinitialize all masters and slaves on the shared bus.
Another embodiment of the present invention is the method for shared bus hang prevention and recovery, corresponding to the device embodiment described above.
Yet another embodiment of the present invention is a shared bus multi-master data communication system which has bus hang prevention and recovery capability. The system includes a shared bus located between an external bus connected to a system processor, and an internal bus connected to an internal processor, and a plurality of bus masters and corresponding slaves connected to the shared bus. Some of the masters are associated with the external bus and other masters are associated with the internal bus. One of the bus masters is a control master associated with the internal processor. The system has a shared bus hang prevention and recovery device connected to the shared bus. The device includes a circuitry and control program instructions. The circuitry performs timing of each pending request of the control master for the shared bus and initiates bus recovery if the shared bus became hung up, when the control master exceeded a pre-determined time period allowed for waiting to acquire the shared bus control and complete the transfer on the shared bus.
The control program instructions monitor and control the circuitry and initialize termination of the transfer in progress causing the shared bus hang-up. During the bus recovery the circuitry prevents bus request grants to the master attached to the external bus until the master subsequent reset. The circuitry initiates transfers for all pending requests for the shared bus from the control master queue, and each transfer is timed and terminated if the shared bus became hung up again. Upon the control master queue clearing, the control program instructions instruct the circuitry to reset and reinitialize all masters and slaves on the shared bus.

Bus hang prevention and recovery for data communication systems employing a shared bus interface with multiple bus masters


In one embodiment, a self-aligned contact (SAC) trench structure is formed through a dielectric layer to expose an active region of a MOS transistor. The SAC trench structure not only exposes the active region for electrical connection but also removes portions of a stress liner over the active region. This leaves the stress liner mostly on the sidewall and top of the gate of the MOS transistor. Removing portions of the stress liner over the active region substantially removes the lateral component of the strain imparted by the stress liner on the substrate, allowing for improved drive current without substantially degrading a complementary MOS transistor.

1. Field of the Invention
The present invention relates generally to integrated circuits, and more particularly to integrated circuit fabrication processes and structures.
2. Description of the Background Art
Stress liners have been employed to enhance the drive current of transistors in integrated circuits. FIG. 1 schematically shows an example integrated circuit structure 100 for a metal oxide semiconductor (MOS) transistor employing a stress liner 105. In FIG. 1, the structure 100 has a gate 101 formed on a gate oxide 103, which is formed on a substrate 102. Active regions 104 (i.e. source and drain) are formed in the substrate 102. The stress liner 105 comprises silicon nitride deposited under process conditions that result in either tensile or compressive strain, depending on the application. A silicon nitride film under tensile stress is referred to as "tensile nitride" and tends to generate tensile strain in the substrate under the gate, while a silicon nitride film under compressive stress is referred to as "compressive nitride" and tends to generate compressive strain in the substrate under the gate.
A problem with stress liners is that although they may be beneficial for one type of MOS transistor, it may be detrimental to the opposite type. This is particularly troublesome in the manufacture of transistors fabricated using complementary metal oxide semiconductor (CMOS) technology. A CMOS integrated circuit typically has a complementary n-channel MOS (NMOS) transistor and p-channel MOS (PMOS) transistor on the same substrate. Although a tensile nitride film may be beneficial to an NMOS transistor, the same film may degrade a PMOS transistor and vice versa. This is graphically illustrated by the plots shown in FIG. 2, which is discussed in H. S. Yang, et al., "Dual Stress Liner for High Performance sub-45 nm Gate Length SOI CMOS Manufacturing," IEDM Tech. Dig., pp. 1075-1078, December 2004. As shown in FIG. 2, while a tensile nitride film increases the drive current of an NFET, it lowers that of a PFET. Likewise, a compressive nitride film increases the drive current of a PFET but lowers that of an NFET.