A method and apparatus for adjusting corneal curvature of the eye comprising an adjustable split device formed of a flexible hollow shell which is implantable into the cornea in encircling relation to the central optic zone of the cornea. The implant is filled by a predetermined amount with a select quantity of solid biocompatible material in various forms such as rings or strands and composed of flexible polymeric materials of various shape and length. The biocompatible filler material is strategically located within the flexible shell to alter its dimensions in thickness or diameter and thereby adjust the corneal curvature to correct for refractive error. Further adjustment of the implant may be made post-operatively after implantation by select removal of the biocompatible filler material, shifting of the material, or addition of new material to the device.

This invention relates to a method and apparatus for adjusting corneal curvature and, more particularly, to an implantable device adapted for insertion into the cornea of an eye and which may be modified in the amount of volume it displaces at the time of insertion and at post-operative times to correct refractive error by adjusting or removing solid material from the implanted device or augmenting said device with solid material.
Ametropia, an undesirable refractive condition of the eye, has three main subdivisions: myopia, hyperopia, and astigmatism. In myopia, by far the most common type of ametropia, the parallel light rays 20 which enter the eye as shown in FIG. 1 come to a focus F1 in front of the retina 24 as shown in FIG. 2. In hyperopia, the rays of light 20 come to a focus F2 behind the retina 24 as shown in FIG. 2 When the rays of light converge to not one, but several foci, it is referred to as astigmatism, in which condition the various foci may all lie before the retina; all lie behind the retina; or partly before and partly behind the retina.
Ametropia is usually corrected by glasses or contact lenses. However, these refractive disorders may also be corrected by surgery. Refractive eye surgery is defined as that surgery on the eye which acts to change the light-bending qualities of the eye. More common current refractive procedures include radial keratotomy, as described in U.S. Pat. Nos. 4,815,463 and 4,688,570 and also laser ablation of corneal stroma, described in U.S. Pat. No. 4,941,093. Various other surgical methods for the correction of refractive disorders have been tried including thermokeratoplasty for the treatment of hyperopia, epikeratoplasty to correct severe hyperopia, and keratomileusis which can steepen or flatten the central cornea. Keratomileusis was introduced by Barraquer of Colombia in 1961 and essentially involves grinding a corneal button into an appropriate shape to correct the refractive error and replacing the reshaped corneal button. Some of the more common keratorefractive procedures are discussed below, none of which have currently shown itself to have all the characteristics of an ideal keratorefractive procedure. The disadvantages of corneal refractive surgery include limited predictability, lack of reversibility, corneal destabilization, optical zone fibrosis, post-operative discomfort, and visual symptoms such as glare, halos, and starbursts.
In radial keratotomy (RK) multiple peripheral radially directed incisions are made into the cornea at 90-95% depth in an attempt to flatten the central cornea and thus correct myopia. The problem of unpredictability of result was tackled by multiple extensive retrospective analyses of the patients in whom surgery had already been performed. These studies revealed certain factors that seemed to control the outcome of the surgery, such as the size of the optical zone, the initial keratometric readings, corneal diameter, corneal rigidity, number of incisions, incision depth, intra-ocular pressure, thickness of the cornea, and degree of astigmatism. Age and sex are also factors that are taken into consideration in most of the nomograms which have been devised to predict what effect to expect for a certain surgery. At one point, many experts in the field considered it nearly impossible to fully and accurately correct patients in one surgery and felt that RK should be considered a two-stage surgery, with the initial surgery to achieve the "ball-park" correction, followed by an enhancement procedure to adjust or titrate the result near the desired outcome for an individual eye. It was felt that because of individual variability which may lead to an under or over-correction in the individual different from that predicted by the nomogram, attempting to fully correct the refractive error in one surgery could lead to over-correction in a not insignificant percent of the surgeries, resulting in hyperopia which is much more difficult to correct. Unfortunately, the second-stage surgery is even less predictable than the initial procedure. No one has yet devised a formula to take into account the profound changes which occur in the cornea after the initial RK, especially when weeks or months have passed. Most studies quote only 50-60% of eyes achieving 20/20 or better visual acuity following RK. Patients who are accustomed to 20/20 or better corrected visual acuity before surgery are not typically satisfied with less than 20/25 or 20/30 uncorrected post-operative visual acuity.
In addition, a gradual hyperopic shift is a major concern after RK. Refractive stability is critical for all refractive procedures but all corneal refractive procedures show significant degrees of instability. To date, there have been no clear explanation of why the cornea is destabilized by RK. A recent report on the long-term results of RK stressed the "natural" hyperopic refractive progression of "normal" eyes as a function of age. It is possible that patients are initially over corrected and the over-correction masked by the patient's accommodative powers. With time and loss of accommodation, the hyperopia may be gradually unmasked with the hyperopia becoming visually symptomatic. At the time of surgery, a patient may be corrected with resultant slight hyperopia and yet have 20/20 vision because of the ability of the lens to accommodate. There is a range of residual correction within which the patient can have 20/20 ncorrected vision. This range varies depending on the individual but probably spans two to three diopters. Even with this range, the percentage achieving 20/20 is only 50-60%. This reflects poorly on the precision of the technique. It is important to note that this range diminishes with presbyopia, or loss of accommodation which usually begins at about 45 years of age. This results in the percentage achieving 20/20 dropping from the 50-60% described above. It is obvious that RK does not qualify as a simple, safe, predictable procedure to adjust the refractive outcome after the initial RK has been performed. Most ideas to contend with the corneal shape after this event have been purely empirical. Thus an easy method to fine-tune a refractive correction that is minimally invasive and easily performed, would require serious consideration.
Laser stromal ablation procedures, such as photorefractive keratectomy (PRK) for correction of refractive disorders are currently popular and have had reasonable success. These procedures are not, however, spared from the problem of unpredictability. Essentially, in the treatment of myopia, laser energy is imparted to the central cornea thereby causing excision of more tissue centrally and a resultant flattening of the cornea. Unfortunately, the final refractive effect is determined not only by the amount of ablation but also by the healing response to the keratectomy. The cornea actively lays down new collagen and the epithelium undergoes a hyperplastic response, among other responses, in an attempt to repair the damage to its surface. This causes regression, or a shift backwards towards myopia, which can gradually occur over a period of months to years. An undesired effect of new collagen deposition is stromal scar formation which manifests as stromal haze and possible decrease in contrast sensitivity by the patient. This corneal stromal opacification is variously referred to as fibrosis, scarring, or haze which is associated with reduced visual acuity and contrast sensitivity, regression of the refractive effect, and poor night vision. Predictability with PRK is an issue, as with RK. Most published results of outcome after PRK treatment for myopia show 80-94% of eyes obtaining uncorrected visual acuity of 20/40 or better while the percentage of patients achieving 20/20 is significantly less. These numbers are in spite of the fact that there is a range of residual refraction at which the patient can still see 20/20 as previously explained. It can be assumed that a significant proportion of those achieving 20/20 after PRK are actually slightly hyperopic. It may very well be that with time, a significant percentage of those patients develop "progressive hyperopia", or an unmasking of the latent hyperopia. So, although the percentage of patients achieving 20/20 after PRK is not acceptable by the definition of an ideal refractive procedure, it may be inflated as was the initial results with RK. Although visual recovery is slow in RK, it is quicker than after PRK. A second laser ablation procedure is usually undertaken with caution since it may cause a greater healing response with even more regression than the initial procedure. Again, as in RK, the laser ablation procedure is not completely predictable, partly because one cannot predict an individual's wound healing response.
For years it has been thought that refractive surgery with intracorneal implants could be used in the correction of ametropia. Early techniques included lamellar removal or addition of natural corneal stromal tissue, as in keratomileusis and keratophakia. These required the use of a microkeratome to remove a portion of the cornea followed by lathing of either the patient's (keratomileusis) or donor's (keratophakia) removed cornea. The equipment is complex, the surgical techniques difficult, and most disappointingly, the results quite variable. The current trend in keratorefractive surgery has been toward techniques that are less traumatic to the cornea, that minimally stimulate the wound healing response, and behave in a more predictable fashion. The use of alloplastic intracorneal lenses to correct the refractive state of the eye, first proposed in 1949 by Jose Barraquer, have been plagued with problems of biocompatibility, permeability to nutrients and oxygen, corneal and lens hydration status, etc. Other problems with these lenses included surgical manipulation of the central visual axis with the concomitant possibility of interface scarring.
More recent efforts toward the correction of refractive errors have focused on minimizing the effects of the wound healing response by avoiding the central cornea. There have been multiple attempts to alter the central corneal curvature by surgically manipulating the peripheral cornea. These techniques are discussed because of their specific relevance to this invention.
Zhivotosvskii, D. S., USSR patent no. 3887846, describes an alloplastic, flat, geometrically regular, annular ring for intracorneal implantation of an inside diameter that does not exceed the diameter of the pupil. Refractive correction is accomplished primarily by making the radius of curvature of the surface of the ring larger than the radius of curvature of the surface of a recipient's cornea in order to achieve flattening of the central area of the cornea. Surgical procedures for inserting the ring are not described.
A. B. Reynolds (U.S. Pat. No. 4,452,235) describes and claims a keratorefractive technique involving a method and apparatus for changing the shape of the optical zone of the cornea to correct refractive error. His method comprises inserting one end of a split ring shaped dissecting member into the stroma of the cornea, moving the member in an arcuate path around the cornea, releasably attaching one end of a split ring shaped adjusting member to one end of the dissecting member, reversibly moving the dissecting member about the path, and thereby pulling the adjusting member about the circular path, made by the dissecting member, withdrawing the dissecting member, adjusting the ends of the split ring shaped adjusting member relative to one another to thereby adjust the ring diameter to change the diameter and shape of the cornea and fixedly attaching the ring's ends by gluing to maintain the desired topographical shape of the cornea.
A major advantage of this ring was that a very minimal wound healing effect was expected. A marked corneal wound healing response would decrease the long-term stability of any surgical refractive procedure. However, there are two distinct problem areas affecting the refractive outcome of surgical procedures treating ametropia:
1. The first problem is concerned with the ability to predetermine the shape and size of a implant that will lead to a certain refractive outcome. In RK or PRK, retrospective studies have been performed that led to the development of nomograms which predict that a certain depth cut or a certain ablation amount will result in a predictable amount of correction. In the case of the ring, eventually nomograms will be developed that can be used to predict a given refractive correction for a given thickness or size of the ring. However, these nomograms can never fully account for individual variability in the response to a given keratorefractive procedure. PA1 2. The refractive outcome also depends on the stability of the refractive correction achieved after surgery. To reiterate, the advantage of the ring would be the stability of the refractive outcome achieved because of a presumed minimal wound healing response. This decreases the variability of the long-term refractive outcome but still does not address the problems posed in the first problem area,--the inherent individual variability, in that while the outcome may be stable, it may very well be an inadequate refractive outcome that is stable.
Another unaddressed issue is that even with the implant, surgeons will aim for a slight under-correction of myopia because, in general, patients are more unhappy with an over-correction that results in hyperopia. Again, the refractive outcome may be more stable than in RK or PRK but it may be an insufficient refractive result that is stable.
Simon (U.S. Pat. No. 5,090,955) describes a surgical technique that allows for modification of the corneal curvature by inter-lamellar injection of a synthetic gel at the corneal periphery while sparing the optical zone and intra-operative removal of such gel to decrease the volume displaced and thus adjust the final curvature of the central corneal region.
Siepser (U.S. Pat. No. 4,976,719) describes another ring-type device to either flatten or steepen the curvature of the cornea by using a retainer ring composed of a single surgical wire creating a ring of forces which are selectively adjustable to thereby permit selective change of the curvature of the cornea, the adjustable means comprising a turnbuckle attached to the wire
There are several mechanisms by which peripheral manipulation of the cornea affects anterior corneal curvature. The cornea, like most soft tissues, is nonlinear, viscoelastic, nonhomogeneous, and can exhibit large strains under physiologic conditions. The whole eye is geometrically extremely complex and the biomechanics technique capable of systematically modeling this reality is the finite element method which assumes small strains (a measure of deformity), homogeneity, and linear elastic behavior. Two simple mechanisms will be briefly described.
A simple example is helpful in understanding the first mechanism. Assume a loose rope R between two fixed points P1 and P2 as in FIG. 4a, which forms a curve, the lowest point P being in the middle. Referring to FIG. 4b, a weight w placed on the rope between the middle point P and one fixed point will cause the central portion of the rope to straighten. The cornea C demonstrated in FIG. 5(a) and FIG. 5(b) behaves similarly, the two fixed points, P1 and P2, analogous to the limbus of the eye and the weight W similar to the intrastromal implant 30 which, when inserted in the cornea in surrounding relation to the corneal central optical zone, causes the corneal collagen fibers to deviate upwards at (21) above the implant, and downwards at (22) below the implant. In essence, this deviation of the cornea around the peripheral implant caused by volume displacement in the peripheral cornea results in other areas of the cornea losing "slack", or relatively straightening as shown at (23).
Mechanical expansion of the implant diameter as shown by expansion of the implant 30 in FIG. 6(b) as compared to FIG. 6(a) also flattens the central corneal curvature whereas constriction of the implant 30 steepens the central corneal curvature, analogous to the two fixed points in the example, FIG. 4(a) and FIG. 4(b), being moved together and causing the rope in the middle to sag more. This is permitted to occur, in part, because the boundary nodes at the limbus are not completely fixed. In summary, there is a micro-deviation caused by the bulk of the implant 30 itself within the peripheral tissue, slightly flattening the central curvature of the cornea, and a constricting or expanding implant altering the fixed points and thus altering corneal curvature. A constricting or expanding implant is likely to cause a less stable refractive outcome because the inward or outward forces of the implant against the corneal stroma may gradually cause further lamellar dissection and dissipation of the forces. A more consistent outcome is likely to be achieved with varying the volume displaced in the peripheral cornea as described by Simon.
The second mechanism is aptly described by J. Barraquer in the following quote. Since 1964, "It has been demonstrated that to correct myopia, thickness must be subtracted from the center of the cornea or increased in its periphery, and that to correct hyperopia, thickness must be added to the center of the cornea or subtracted from its periphery." Procedures involving subtraction were called `keratomileusis` and those involving addition received the name of `keratophakia`. Intrastromal corneal ring add bulk to the periphery and increasing the thickness of the ring results in a more pronounced effect on flattening of the anterior corneal curvature by "increasing (thickness) in its periphery".
The ideal keratorefractive procedure allows all the advantages of eyeglasses or contact lenses, namely, being able to correct a wide range of refractive errors, accuracy or predictability, allowing reversibility in the event that the refractive state of the eye changes and it becomes necessary to adjust the correction again, yielding minimal complications, and associated with technical simplicity, low cost, and being aesthetically acceptable to the patient. The goal of refractive surgeons should be to achieve 20/20 uncorrected visual acuity with long-term stability in greater than 95% of patients. None of the currently available refractive surgery procedures generate this degree of accuracy or stability.
Once again, an easy procedure to post-operatively fine-tune the refractive correction and corneal curvature which is often influenced by changes in corneal hydration status, wound healing responses, and other unknown factors, is not available. Each of the techniques described suffers from a limited degree of precision. In this disclosure of the present invention, an easy method to adjust the refractive outcome after the corneal curvature has stabilized, a method that is minimally invasive, a method causing minimal stimulation of the wound healing processes, allowing repetitive adjustments as deemed necessary, and being almost completely reversible is described. It may make moot the pervasive issue of unpredictability and make obsolete the application of procedures which rely heavily upon nomograms to predict refractive outcome and are thus unable to adequately account for an individual's variable response to the procedure.

Method and apparatus for adjusting corneal curvature using a solid filled corneal ring


The exemplary embodiments of the invention provide at least a method and an apparatus to determine a beacon signal for a network node, where the network node is configured to connect with a cluster of access points in a wireless communication network, and where the beacon signal identifies the cluster; and send the beacon signal towards the wireless communication network. Further, the exemplary embodiments of the invention provide at least a method and an apparatus to determine a dominant access point of a cluster of access points based on signaling from at least one access point associated with the cluster of access points; and in response to the determining, direct communications towards the dominant access point of the cluster of access points.

Wireless data traffic is projected to grow by 26× between year 2010 and 2015 exceeding 6×10{circumflex over ( )}18 bytes per month by 2015. Recent innovations in cellular air-interface design, culminating in 3GPP LTE, provide spectral efficiency performance that will be difficult to improve on. To meet the growing traffic demand, the cellular capacity per square meter must be increased by either shrinking cell-sizes or acquiring additional spectrum. To that end, the industry is already pursuing smaller cells through the heterogeneous networks of picos and macros. Similarly, 500 MHz more of spectrum is being made available below 6 GHz to help meet the growing demand. While these efforts will help meet demand in the short term, the projected growth rate of data traffic will exceed this added capacity in the longer term. Moreover, the available spectrum below 6 GHz is limited and there are practical limits to how small cells can shrink. Therefore, the cellular industry must look for new resources in frequencies above to 6 GHz to meet this demand.

Millimeter wave access architecture with cluster of access points


The present invention relates to the discovery that compounds isolated from the leaves of the plant Eucalyptus camaldulensis can be used to treat or prevent hyperglycemia and/or hypertension.

High blood sugar (hyperglycemia) affects people who have diabetes. Several factors can contribute to hyperglycemia in people with diabetes, including food and physical activity choices, illness, nondiabetes medications, or not taking enough glucose-lowering medication (see e.g., http://www.mayoclinic.com/health/hyperglycemia/DS01168).
Research into alternative treatment for diabetes, such as plant treatments, may provide valuable clues for the development of new oral hypoglycaemic agents. Eucalyptus camaldulensis, commonly called River Red Rum, is a species being investigated for the hypoglycaemic principle present within the leaves. The eucalyptus is a large, fast-growing evergreen from the Myrtaceae family having over 800 species.


A wearable device comprises one or more circuit substrates comprising electrically conductive parts, a radio unit and a loop antenna coupled to the radio unit. The loop antenna comprises a conductor formed into a loop, wherein the electrically conductive parts of at least one of said one or more circuit substrates substantially act as a ground plane for the loop antenna. Said at least one circuit substrate is positioned substantially on the same plane with the loop and such that at least the electrically conductive parts of said at least one circuit substrate are within an area defined by the loop when said at least one circuit substrate and the loop are observed perpendicularly with respect to a plane of the loop in order to minimize the ground plane effect of the electrically conductive parts of said at least one circuit substrate on the loop antenna.

Wearable devices such as wrist-worn devices can nowadays comprise a plurality of functions. Examples of such functions are time display, measurement and display of various physical quantities like temperature, air pressure, heart beat rate and so on. A wearable device can also comprise a radio unit for receiving and/or sending radio signals, for instance a GPS receiver (Global Positioning System).
Integrating an antenna into a wearable device comprising a radio unit can be problematic because other electronics in the device, particularly a circuit substrate, such as a printed circuit board, comprising conductive parts, may act as a ground plane for the antenna and deteriorate the performance of the antenna. Also the proximity of a human body can deteriorate the performance of the antenna especially in a wrist-worn device. Furthermore, a wearable device is typically of limited size and on the other hand the antenna should not be very protruding which also constricts the antenna design.
A commonly used antenna type that can be placed inside a wearable device is a so-called patch antenna. A patch antenna typically comprises a planar radiator and a ground plane parallel thereto. A problem with the patch antenna type is the relatively large surface area it has on account of which it can be difficult to place a patch antenna inside a wearable device, especially a small wearable device.
U.S. Pat. No. 4,977,614 describes an antenna incorporated into a wristband of a wrist-worn device. A problem with this kind of antenna design is that the antenna may be strongly coupled to the wrist of a user thus impairing the antenna performance.
U.S. Pat. No. 5,926,144 describes an antenna located within the housing of a wearable electronic device. In the solution presented the antenna is a loop antenna which is positioned vertically with respect to the housing of the device. A problem with this kind of design is that it potentially increases the vertical space needed inside the housing.
U.S. Pat. No. 5,768,217 describes also an antenna located within the housing of a wearable electronic device. In the solution presented the antenna is a loop antenna which is positioned horizontally with respect to the housing of the device on top of the circuit board and the components therein. The potential problem with this kind of design is that especially the circuit board may act as a ground plane for the antenna and affect the performance of the antenna in an undesirable way.


The subject matter described herein is directed towards a technology that increases the reliability of transmitting information, by propagating received information in a location-controlled and route managed multiple-stage chain communication in a wireless communication system. A transmitting device transmits a broadcast or group-cast communication message in conjunction with transmitter and receiver location data (e.g., absolute or quantized coordinates). An intermediate device that receives the communication message determines a communication path based on the received location data, and determines whether the intermediate device is within the communication path based on its own location. Only intermediate devices that are within the communications path, and that otherwise satisfy retransmission policy, perform the retransmission. In one aspect, the communication path that is determined can be shaped based on one or more other factors, such as whether the communication message is highly reliable data traffic.

In LTE wireless communication systems, vehicle-to-everything (V2X) generally utilizes the Sidelink interface, alternatively referred to as PC5, to enable V2X communications, including V2V (vehicle-to-vehicle) communications, V2I (vehicle-to-infrastructure) communications, V2P (vehicle-to-pedestrian) communications and V2N (vehicle-to-network) communications. The PC5 interface is built based on a mesh architecture of peer-to-peer device communication. LTE V2X also supports Uu interface (the radio interface between the mobile device and the radio access network) enhancement to assist the PC5 communications.
NR V2X is being designed to support enhanced V2X use cases such as vehicle platooning that enables the vehicles traveling together to dynamically form a platoon. NR V2X is also being designed to support extended sensors that enable the exchange of raw or processed data gathered through local sensors or live video images among vehicles, road side units, devices of pedestrian and V2X application servers. Further, NR V2X is being designed to support advanced driving that enables semi-automated or full-automated driving. Each vehicle and/or RSU shares its own perception data obtained from its local sensors with vehicles in proximity and that allows vehicles to synchronize and coordinate their trajectories or maneuvers. Each vehicle shares its driving intension with vehicles in proximity too.
Existing (e.g., PC5-based) interfaces assume a mesh architecture in which every node is a peer to each other. This approach does not rely on any network infrastructure. However, spectrum efficiency cannot be very high because of the peer-to-peer structure. Another drawback of this mesh architecture is that it is not compatible with infrastructure-based cellular networks that utilize a hierarchical architecture. As a result, a separate spectrum needs to be obtained to deploy a V2X service based on a peer-to-peer mesh network architecture, which is very costly.
A wireless communication system, such as, for example, a three-party communication framework for V2X can be implemented, in which the three-party communication framework imposes a hierarchical structure in the peer-to-peer network. In the three-party communication framework, a given node—typically a node other than the transmitter and the receiver—is designated to coordinate the radio resource usage. This chosen node, (which can be chosen by the network or elected by other, managed nodes) can be referred to as a "local manager" or a "scheduler node" (Node-S), and is responsible for the scheduling and resource allocation among the nodes it manages, e.g., a transmitting node (Node-T), and one or more receiving node(s) (Node-R(s)). Such a three-party communication framework is beneficial in advanced use cases such as vehicle platooning, whereas a designated leader node is responsible for leading and managing the platoon.
The three-party communication might not however be sufficient to enable highly reliable communication between nodes that form a V2X connection, due for example to blockage, especially in mm-Wave frequencies, or due to an edge effect, where the transmitting node is too far from a node-S or a Node-R to reliably transmit the data.
A chain rebroadcast solution is able enhance the reliability of such sidelink communications by letting receiver user equipments rebroadcast a received message, which achieves a chain effect. While this solution effectively improves reliability, significant and unnecessary transmission and interference can result in the network, generally because the rebroadcast is "blind" in the sense that there is no route management. However, traditional route management is difficult to apply in a full mesh-based mobile environment, because any routing table would need to be relatively large and require frequent updating, and because it is difficult to guarantee a synchronized routing table with a mesh-like structure.

Location-based route management for vehicle-to-everything relay communications


A lower body exercise device for use with a seat. Other embodiments of the seat mountable lower body exercise device include a lower body exercise mechanism (20) for simultaneous use by a user while working, reading or doing other sedentary activities, and a simple installation mechanism (10) for various forms of seat. In addition, simple detachable function (11a), (11c), and multiple adjustment functions (21aa), (23), (30) for various user's circumstances is available, and one or more exercise alteration is also available by adjustment (30), (33a), (27c), (24b). Other embodiments include a magnetic cycle system which may reduce the exercise device body (21″) in size.

1. Field
This application generally relates to exercise device, specifically to a seat mountable exercise device with alternative lower body exercise variations for use on any type of seat or chair.
2. Prior Art
Extended period of time of active hours is being increasingly required to be spent sedentarily, whether working in an office, watching television, using computer or playing videogames. Prolonged immobilization or sedentary position may not only generate discomfort, especially on the lower-body, but increasing medical studies are reporting the close connection with health risks such as blood circulatory difficulties, obesity, deep-vein thrombosis, varicose vein, mental state decrease and/or other problems. Most physical activity is available in a location or area away from office or desk, requiring additional time investment and the trouble to prepare for exercise. Considering modern day environment, it demands extra effort and time which is difficult for most people to keep up with over long period of time, whereas exercising while working at the office is being introduced as the new alternative for an efficient and convenient physical exercise.
Numerous exercise devices which provide exercise function while sitting at an office chair or simultaneous performance of physical exercises and office work have been introduced, usually by attachment of the device to either a desk or a chair, or a seat with a built-in exercising function. The following examples are of typical prior art to this field of endeavor.
U.S. Pat. No.:Des. 158,675LongfellowJan. 13, 19493,751,033RosenthalAug. 7, 19733,968,963SileoJul. 13, 19764,601,464MouselJul. 22, 19864,913,423FarranApr. 3, 19905,044,633RiceJan. 9, 19915,108,092HurstApr. 28, 19925,599,260RovinskyFeb. 4, 19975,690,594MankovitzNov. 25, 19975,807,212NelsonDec. 4, 19965,833,575HolslagNov. 10, 19986,056,675AruinMay 2, 20006,099,445RovinskyFeb. 4, 19986,866,618B2Rusinak-ConnorsMar. 15, 20059,813,059WillisSep. 26, 200210,698,295AndreJul. 22, 200410,950,931NeffMar. 10, 200511,766,299BowserOct. 18, 200711,797,090Oren; ReismanJan. 3, 2008
However, most prior art describe devices that have rather limited range of movement, exercise capacity, or is applicable only for a limited type of chair or are too bulky to use under conventional office desks. Moreover, considering that the majority users would use these devices in the office where the furniture belong to the company, easy installation and removal without damaging the office furniture is important while requiring small space for diverse office circumstances. Prior arts which satisfy such requirements either have weak resistance on the pedal bearing or require the user to replace the whole chair itself, as the chair has built-in exercise system. Otherwise, some prior art describe devices that may be used in offices but require additional time for exercise, instead of simultaneous exercise with conventional office work such as computer or phone conversation.
Health related studies show that exercising the lower body, such as thighs where large amount of muscles are formed, burns more calories while it also prevents deep-vein thrombosis, varicose vein and other blood circulatory troubles, thus is especially recommended for people with extended stationary or sedentary work. Efforts to solve such exercise deficiency issue with more efficient and effective lower body movements for office workers have lead to the following prior art examples.
U.S. Pat. No.:5,813,947DensmoreNov. 8, 199610,265,501KehrbaumApr. 8, 200411,380,642PowellNov. 2, 200611,583,764PerryApr. 24, 2008
Although above-noted prior art propose most efficient and effective calorie-burning exercise system that could be performed in the office, few concerns are raised. One is the eyesight failure which might occur when performing computer or desk work while walking, since minor but consistent motion would disturb and fatigue the eyes. Another concern is the budget, since the mentioned prior art require the user to purchase a new desk, system or work station which is rather costly. It also may attract undesired attention from colleagues, since the system consumes much space and requires the user to work while walking. For companies that wish to install such exercise work station system for the employees' health and benefits, the noise that the treadmill may produce is a negative aspect since it could disturb other employees. The fact that mentioned prior art are power consuming is also another aspect which needs to be addressed for eco-friendly environment.
Advantages of this application of one or more aspects are to provide a convenient mountable lower body exercise device without damaging the existing furniture, and which could be mounted to any form of chair including conventional chairs and couch. Other advantages of one or more aspects are to provide variations of lower body exercise, such as aerobic exercise and muscle training, which may be practiced simultaneously while performing other activities such as conventional office work, doing simple works at a table or desk, watching television or video games, without requiring much movement of the upper body to prevent eyesight fatigue. This application describe device which also does not require electric power and is quiet enough to exercise in the office without disturbing others. These and other advantages of one or more aspects will become apparent from a consideration of the ensuing description and accompanying drawings.


The invention(s) relates to a wafer test system including a circuit to communicate an overdrive to a chuck, the chuck moving a wafer towards a probe head responsive to the overdrive, a circuit to measure a contact resistance of at least one channel in each of a plurality of dies associated with the wafer using the probe head, a circuit to compute a per channel standard deviation responsive to measuring the contact resistance, a circuit to compare the standard deviation on the at least one channel to a threshold, and a circuit to increase the overdrive responsive to the comparison.

1. Field of the Invention(s)
The invention(s) relates to a semiconductor test system and method. More particularly, the invention(s) relates to a semiconductor test system and method that improves probe head to wafer contact using dynamic overdrive compensation.
2. Description of the Related Art
Semiconductor devices, e.g., wafers and integrated circuits, are typically tested at various points in their manufacture. This includes the wafer-test step, where the circuit units are tested while they are still part of a wafer and have not been packaged into individual units. Testing ensures the devices—and the manufacturing processes used to produce them—are working properly and within acceptable quality ranges.
A typical wafer-test is performed as follows. The wafer is placed on a chuck or similar mechanical tool that moves the wafer and brings the device under test (DUT) into contact with an interface unit, e.g., a sort interface unit (SIU). The SIU provides electrical signals received from a tester to the wafer through contact pins positioned on a probe head (which is a part of the SIU). The contact pins are often spring-loaded.
In some cases, the probe head flexes or bends due to the force from the chuck, resulting in poor electrical contact. Poor or inconsistent electrical contact can also result from contact pin non-planarity. That is, some pins are shorter than others such that the shorter pins do not connect to the wafer. Wafer-to-wafer variations can also contribute to poor electrical contact.
Other factors such as airflow within the prober and manufacturing floor shakes might cause enough pin movement to prevent reliable contact with the wafer. Poor or inconsistent electrical contact increases test failures, lowering yield and throughput.
One method of improving probe to wafer contact is to use Optical Z Alignment (OZA) followed by aggressive overdrive. In OZA, the chuck moves the wafer in X, Y, and Z directions to optically align it with the probe head's contact. Then, the chuck is significantly overdriven in the Z direction such that the wafer is brought into pin contact with increased force, whether necessary or not. This aggressive overdrive might cause long-term damage to the SIU and, more particularly, to the probe head. The overdrive amount is typically chosen to work with most SIUs and wafer types. As a result, a limitation of the OZA method followed by aggressive overdrive is that it does not account for SIU-to-SIU and wafer-to-wafer variations. The amount of overdrive, therefore, is chosen aggressively to envelope most SIUs and wafer lots. And the amount of overdrive is chosen without specific knowledge of the particular SIU used and the particular wafer being tested. The result is a very high overdrive that might cause long-term damage to the SIU or wafer.
Electrical Z Alignment (EZA) addresses some of the disadvantages associated with OZA. In EZA, the chuck moves the wafer closer to the SIU probe head until a bare electrical contact is established on all pins. A bare contact is established on all channels when any current flows through the pins. Once a bare contact is established on all pins, the test system overdrives the chuck to account for wafer-to-wafer variations, much like in the OZA method we describe above. Here, however, the overdrive used in the EZA method is not as aggressive or significant as it is in the OZA method. In both methods, however, the amount of overdrive is determined heuristically and its accuracy cannot be guaranteed until the product is mature.
If a contact between the probe head and the wafer is not reliable, the wafers often need to be re-tested, increasing test time and consequently, test cost.

Dynamic overdrive compensation test system and method


Provided is a technology which quantitatively measures blood flow in the vicinity of circulatory organs. An ultrasound image capture device according to the present invention removes an image portion corresponding to an organ shape by taking the difference of a multi-frame ultrasound image, and thereafter computes a measured value of a blood flow velocity vector on the basis of a plurality of images at different timings (as per FIG. 3).

In circulatory system that circulates bloods in body, efficiencies and forms of blood circulation have a close relation with circulatory diseases. For example, a circulatory system with low efficiency stresses the heart, which increases a risk of heart failure. The efficiency of blood circulation can be described by momentum or energy of blood.
Not only regarding heart but also in blood vessel disease such as arteriosclerosis, it has become apparent that a shear stress describing a kinetic exchange between a blood vessel and a blood flow when the blood flows is closely concerned with diseases (Non Patent Literature 1).
In order to examine circulation efficiency or blood flow dynamic state of a circulatory tissue, it is required to acquire the mechanistic mutual relation between the circulatory tissue and the blood flow. In order to achieve it, it is required to quantitatively calculate the circulatory tissue motion and the blood flow vector around the boundary between the circulatory tissue and the blood flow, and to digitize its effects to analyze them.
Patent Literature 1 listed below describes a method for calculating a blood flow vector by integrating a plurality of differential images.

Ultrasound image capture device, ultrasound image capture method, ultrasound image capture program


A metering system for distributing an agricultural product in a field includes a drive input and a drive shaft coupled to the drive input and configured to be driven in rotation by the drive input. The metering system also includes a first meter box assembly having a first housing, a first metering shaft extending through a first plurality of meter rollers within the first housing, and a second metering shaft extending through a second plurality of meter rollers within the first housing. The metering system includes a second meter box assembly having a second housing, a third metering shaft extending through a third plurality of meter rollers within the second housing, and a fourth metering shaft extending through a fourth plurality of meter rollers within the second housing. Each metering shaft is configured to be independently driven by the drive shaft.

The invention relates generally to agricultural metering systems and, more particularly, to a sectioned meter box assembly for an agricultural metering system.
Generally, seeding implements are towed behind a tractor or other work vehicle. These seeding implements typically include one or more ground engaging tools or openers that form a seeding path for seed deposition into the soil. The openers are used to break the soil to enable seed deposition. After the seeds are deposited, each opener is followed by a packer wheel that packs the soil on top of the deposited seeds.
In certain configurations, an air system is used to meter and deliver agricultural product (e.g., seeds, fertilizer, etc.) to ground engaging tools within the seeding implement. Certain air systems include a metering system configured to deliver metered quantities of product into an airflow that transfers the product to the openers. Certain metering systems are configured to rotate a shaft of a meter box assembly which, in turn, rotates each metering section of the meter box assembly. As such, the metering system may be engaged to provide product to each opener coupled to the meter box assembly, or stopped to block product delivery to each opener. Unfortunately, the metering system may deliver product to openers positioned above soil that has already received product, or soil that should not receive product (e.g., a headland), thereby resulting in wasted product.


A method of securely transferring files from an un-trusted to a trusted network is disclosed. A file that is an archive file of many component files is separated into constituent files. Each file is stored on a server connected to an un-trusted network, and a series of initial checks, such as virus, file size, and file extension are performed. If the files pass, additional, file format specific security rules are applied. An open format transform is performed on proprietary format type files, and embedded file components are separated out. A user-definable security rule set is performed on each open format transform component. If all security tests pass, the file is reassembled and saved as a trusted file in the same format as the original file.

With each coming year, office documents are required or expected to contain richer media content and more diverse methods of displaying data. The advantage is that it is substantially easier to produce professional-looking documents from the desktop.
These richly formatted, unstructured data files make it substantially easier to pass malicious code as well. Interpreters such as Microsoft Word or Ghostview open these files and may inadvertently execute malicious scripts, macros, etc. contained within the seemingly innocuous office file.
Deterring the malicious content is a challenge. The simplest solution for eliminating the risk of passing this kind of content is to simply prohibit the transfer of files that can contain malicious code. This leaves simple ASCII text files and images, among others, that can be transferred, making these content-oriented files less useful.
The key to safely emailing office documents is recognizing and prohibiting any code that could cause an interpreting application to do anything other than render the intended document. However, the list of known problems, vulnerabilities, and exploits is continually evolving. Since email exploit shields usually operate by specifying what a "bad" file or "bad" content, is, they cannot combat vulnerabilities newer than the last definition of "bad" files. This is an inherent design flaw of all signature-based solutions.
U.S. Pat. No. 5,940,591, entitled "APPARATUS AND METHOD FOR PROVIDING NETWORK SECURITY," discloses a method of performing security functions on a non-secure network. The method uses a multi-level secure network architecture to support services to many domains from one, offering communications services (video, audio, others) over a trusted security protocol, which exists at the security perimeter created by the secure network interface units. The guard is a session manager to an external set of networks. This method requires the selection of portions that do not require the same level of trust. Although the system checks access control, individual files are not verified for malicious code. The present invention is not limited in this regard. U.S. Pat. No. 5,940,591 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. No. 6,584,508, entitled "ADVANCED DATA GUARD HAVING INDEPENDENTLY WRAPPED COMPONENTS," discloses a method of increasing the security of a data guard. The data guard is configurable, for items such as HTTP traffic, SMTP traffic, etc. A set of proxy servers sits between an "internal" network and an "external" network and examines traffic. The first proxy server communicates with the internal computer network, and the second proxy server communicates with the external network. Protocol specific operations are converted to protocol independent data. Administrators define security policies that affect the information going between the proxy servers, deciding which information to pass. The system uses two-way communications that provide an adversary with information regarding the security protocols used. The present invention is not limited in this regard. U.S. Pat. No. 6,584,508 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. No. 6,826,694, entitled "HIGH RESOLUTION ACCESS CONTROL," discloses a method for performing security functions at a firewall. After a packet is received at a firewall, the header is checked. A rule specific to the header information is applied to analyze the content of the packet at the firewall. Changing the packet header to a benign file type is relatively simple. Malicious code may then pass through the firewall. The present invention is not limited in this regard. U.S. Pat. No. 6,826,694 is hereby incorporated by reference into the specification of the present invention.

This patent is subject to a terminal disclaimer.

The United States of America as represented by the Director, National Security Agency


A surface wave apparatus is disclosed having reduced sound attenuation across a surface along a known path having a path distance when compared to sound attenuation along a same path distance through air. The surface wave apparatus includes a plurality of cells defining a first surface. Sound presented at the first surface forms a surface wave over the surface and proximate thereto. Each cell includes four bounding walls and a bottom. Two of the bounding walls act to guide the sound within the known path and two are disposed across the known path to form a structure supporting formation of surface waves.

This invention relates to a sound-field-modifying structure and more particularly to a sound-field-modifying structure that makes use of air-coupled surface waves to provide noise reduction, spectral shaping, or sound amplification.
The modification of sound fields using passive, physical structures is useful in many application areas. These include applications where noise reduction or attenuation is the main goal, as with highway noise barriers or sound-absorbing ceiling tiles. In other applications, sound amplification is desired, as with parabolic dish microphones. And others involve attenuation in some frequency bands resulting in relative amplification in others, i.e., spectral shaping of sounds, as with the design of concert halls. Typical strategies include the use of porous damping materials, the incorporation of Helmholtz resonators, and the use of barriers, shaped reflectors and diffusers.
It is also possible to make use of an entirely different physical mechanisms, such as air-coupled surface waves, to achieve improvements in performance in all of these areas. Air-coupled surface waves form and propagate over porous surfaces that have been designed to have appropriate acoustic impedance. Acoustical energy collects into the surface wave and is localised close to the surface as it propagates over the surface. These structures are useful for sound attenuation through the introduction of acoustically absorbing materials into sections of the surface wave structure, so that acoustical energy is trapped into a surface wave and then dissipated by the absorbing materials. Thus, improved noise reduction is achieved.
For example, in U.S. Pat. No. 4,244,439 entitled xe2x80x9cSound-absorbing structurexe2x80x9d, issued to Wested, a structure for use to reduce traffic noise is proposed. The mechanism used to reduce the noise, although not explicitly noted as such, is air-coupled surface waves.
Different frequency ranges are addressable in different fashions, so spectral shaping of different signal types such as speech, music, and noise are achievable. Optionally, a surface wave structure is designed so that it behaves differently for sound arriving from different directions: there is a directivity potential that is optionally exploited. Also, surface waves propagate with a phase speed that is different than the free field sound speed.
Efforts are often made to reduce noise in boardrooms and conference rooms using absorptive panels and carpets. However, such noise control efforts also reduce the intensity level of speech signals resulting in difficulties hearing individuals at opposing ends of a room, particularly for long rooms. This reduced audibility is even more of a problem when a microphone is being used to pick up the speech signals because the visual cues are not present at the remote listening end. Two procedures in current use to reduce the above noted problem are (i) reinforcing the speech signals along the length of a boardroom by installing an overhead, ceiling-mounted reflective panel and (ii) use of electronic amplification with microphones at each talker position. However, the installation of an overhead reflector can involve considerable structural, aesthetic and lighting considerations and, moreover, the effects of the original noise control efforts are offset by such an approach. Electronic amplification requires electronic hardware, such as microphones, amplifiers, loudspeakers and mixers, and a technician to ensure that equipment is running properly and levels are appropriately set.
It would be advantageous to provide a method and structure for improving acoustic communication.
According to an embodiment of the invention there is provided a surface wave apparatus having reduced sound attenuation across a surface along a known path having a path distance when compared to sound attenuation along a same path distance through air comprising:
a plurality of cells defining a first surface for supporting acoustical communication between a sound field incident on the first surface and the plurality of cells, each cell including:
an end that is approximately acoustically sealed such that most acoustic energy does not pass therethrough and spaced from the first surface for providing an effective acoustic surface impedance for which air-coupled surface waves form and propagate at selected sound frequencies,
at least a bounding sidewall having 2 opposing bounding sides, between the first surface and the end, that are approximately acoustically sealed such that most acoustic energy does not pass therethrough, the 2 opposing bounding sides of adjacent cells approximately defining boundaries of the known path,
the at least a bounding sidewall having further sides between the first surface and the end spaced apart by a distance less than a wavelength of sound at a known frequency and each disposed across the known path on the surface wave apparatus.

Air-coupled surface wave structures for sound field modification


A posture control apparatus, comprising a control unit that determines, on a basis of a static acceleration component, a gravity direction in a holding apparatus holding an object to be held, the static acceleration component being computed on a basis of a first acceleration detection signal and a second acceleration detection signal, the first acceleration detection signal being acquired by detecting a dynamic acceleration component acting on the holding apparatus, the second acceleration detection signal being acquired by detecting the dynamic acceleration component and the static acceleration component acting on the holding apparatus, and controls, by controlling posture of the holding apparatus on a basis of the gravity direction, posture of the object to be held.

In the past, a camera gimbal has been widely known as an apparatus that allows a camera to stably captures an image (see, for example, Patent Literature 1). The camera gimbal has a mechanism for rotating the camera around two axes or three axes, and controls the posture of the camera in space by rotating this mechanism.
The camera gimbal is often used by being held by a hand or placed at a predetermined place. However, in recent years, the camera gimbal is placed on a flight vehicle such as a drone for use in some cases (see, for example, Patent Literature 2).

Posture control apparatus, holding apparatus, posture control method, and program


A full phase shifting mask (FPSM) can be advantageously used in a damascene process for hard-to-etch metal layers. Because the FPSM can be used with a positive photoresist, features on an original layout can be replaced with shifters on a FPSM layout. Adjacent shifters should be of opposite phase, e.g. 0 and 180 degrees. In one embodiment, a dark field trim mask can be used with the FPSM. The trim mask can include cuts that correspond to cuts on the FPSM. Cuts on the FPSM can be made to resolve phase conflicts between proximate shifters. In one case, exposing two proximate shifters on the FPSM and a corresponding cut on the trim mask can form a feature in the metal layer. The FPSM and/or the trim mask can include proximity corrections to further improve printing resolution.

1. Field of the Invention
A full phase shifting mask for patterning a metal layer in an integrated circuit is described. In particular, the full phase shifting mask can be used with a damascene process, thereby allowing hard-to-etch materials, such as copper, to be used for the metal layer.
2. Description of the Related Art
A standard binary mask includes a patterned opaque (e.g. chrome) layer formed on a transparent (e.g. quartz) substrate. The pattern can be transferred onto the wafer using optical lithography. Specifically, for each layer of the circuit design, a radiation (e.g. light) source is shone on the mask (wherein the term mask can also refer herein to a reticle) corresponding to that layer. This radiation passes through the transparent regions of the mask and is blocked by the opaque regions of the mask, thereby selectively exposing a photoresist layer on the wafer.
The areas in the photoresist layer exposed to the radiation, i.e. irradiated areas, are either soluble or insoluble in a specific solvent, called a developer. If the irradiated areas are soluble, then the photoresist is called a positive photoresist. In contrast, if the irradiated areas are insoluble, then the photoresist is called a negative photoresist. After development of the photoresist layer, the underlying semiconductor layer no longer covered by photoresist can be removed by an anisotropic etch, thereby transferring the desired pattern onto the wafer. This process can be repeated for each layer of the integrated circuit design on the wafer.
A conventional process for patterning a metal layer comprises depositing that metal layer on the wafer and then depositing a positive photoresist layer on the metal layer. The positive photoresist can then be exposed using a clear field binary mask (wherein the opaque pattern on the mask represents features in the layout). At this point, etching can be performed to generate the desired pattern in the metal layer.
This process works well for metal patterns having critical dimensions greater than 0.13 microns. However, to enhance device performance at smaller critical dimensions, the semiconductor industry is moving from aluminum to copper. Unfortunately, copper is very difficult to etch. Therefore, a conventional metal process as described above cannot be used for a copper layer.
However, a damascene process can be used to form a copper pattern. The damascene process can include forming an oxide layer on the wafer and then depositing a negative photoresist layer on the oxide layer. The negative photoresist can be exposed using the clear field binary mask. After exposure, the exposed portions of the oxide layer can be easily etched to form the desired pattern. At this point, copper can be deposited and planarized (e.g. using a CMP operation), thereby forming the desired pattern in copper.
However, positive photoresists are currently the dominant resists for many applications as they provide better resolution than negative photoresists. Therefore, a need arises for a technique of patterning a metal layer, particularly a hard-to-etch metal, using a positive photoresist.

Full phase shifting mask in damascene process