An apparatus on a vehicle comprises one or more sensors, one or more nozzles that output fluid to clean the respective one or more sensors, and a compressor that generates fluid such as compressed air. The compressor is in fluid communication with the one or more nozzles. The apparatus further comprises one or more processors, and a memory storing instructions that, when executed by the one or more processors, cause the system to predict a trajectory of the vehicle and control an operation of the compressor based on the predicted trajectory of the vehicle.

A vehicle, such as an autonomous vehicle, includes a myriad of sensors that provide continuous streams of sensor data captured from the vehicle's surrounding environment. Such sensor data enables an autonomous vehicle to perform a number of functions that would otherwise be performed by a manual human operator including various vehicle navigation tasks such as vehicle acceleration and deceleration, vehicle braking, vehicle lane changing, adaptive cruise control, blind spot detection, rear-end radar for collision warning or collision avoidance, park assisting, cross-traffic monitoring, emergency braking, and automated distance control. A vehicle such as an autonomous vehicle can include a variety of different types of on-board sensors including, for example, cameras, light detection and ranging (LiDAR) systems, radar systems, Global Positioning System (GPS) devices, sonar-based sensors, ultrasonic sensors, accelerometers, gyroscopes, magnetometers, inertial measurement units (IMUs), and far infrared (FIR) sensors. On-board vehicle sensors disposed on an exterior of a vehicle may be provided in or integrated with protective housing to protect the sensors from damage. The housing, however, can be subjected to environmental elements such as rain, heat, wind, dust, or the like that can impede the ability of sensors encased in the housing to perform their functions. Technical solutions that mitigate the effect of such factors on sensor performance and enhance the functional capabilities of sensors, such as cleaning, are described herein.
Additionally, noise may be generated from the operations of the cleaning. Technical solutions that mitigate the effects of the noise specifically generated from the operations of the cleaning are described herein. Furthermore, cleaning needs of the sensors and scheduling of the cleaning of the sensors may depend on various factors such as types of the sensors, desired levels of cleanliness of the sensors, along with external factors such as traffic, weather, vehicle speed, and background noise. Technical solutions may account for the effects of the external factors in adjusting the cleaning needs and cleaning schedule accordingly, while providing a cleaning operation tailored to the particular sensor rather than a one size fits all approach.


The invention relates to a process for sanitizing post-consumer wastepaper fibers for liquid packages and containers, a paper product for food packaging and a liquid food container. The process comprises providing paper fibers from a wastepaper recycle process, adding water to the paper fibers to achieve a slurry, de-watering the slurry to obtain a paper fiber stream and passing the fiber stream through a mixing device while heating the fiber stream and supplying hydrogen peroxide in the mixing device.

Various processes for recovering paper fibers from scrap paper such as paperboard food cartons and packages, office waste paper, magazines and newspapers have been proposed. Typically, these recycle processes involve treating the waste paper in a hydrapulping machine wherein the fibers are separated by the agitation of the water, and the use of caustic soda or similar reagents break down the integrity of the waste paper. This results in a stream of separated paper fibers which may be passed through various screening devices to remove contaminants, and the resulting slurry containing the paper fibers may pass through a de-inking process. After appropriate treatment, which may include bleaching, the slurry of paper fibers passes through a de-watering stage, so that the recovered paper fibers are collected in an essentially dry state and may be packed in bales for subsequent use in making paper. An example of a recycle process that would be suitable for obtaining dry paper fibers is disclosed in U.S. Pat. No. 5,390,860, "Method and Apparatus for Separating Paper Fiber and Plastics from Mixed Waste Materials", which is incorporated herein by reference.
If recovered paper fibers are to be used for making packages or containers for food products, government regulations require that they meet the same standards as for virgin paper fibers, e.g., the recommendation by the International Dairy Federation (IDF) of a maximum bacterial load of 250 colony-forming units per gram ("cfu/g").
In a typical paper plant, virgin pulp is digested and bleached in a slurry that is supplied directly to the paper-making machine. Recycled paper fibers are often processed in local recycle plants, dried, stored in bales, and subsequently transported to paper-making plants for further processing into cartons and containers. While the bales of fibers are being stored, microorganisms that are present may multiply and cause contamination of the final paper product. It has been proposed to sterilize recycled fibers by heating the fibers to a pasteurizing temperature. However, this sterilization process requires steam-heating equipment and vessels, and thus can be very expensive. Addition of bactericides to a dilute pulp slurry has also been proposed to control bacterial load in food packaging, but also requires substantial input of energy and chemicals to achieve the desired results. Moreover, use of bactericides may leave undesirable residues in the pulp. The efficiency and economy of the recycle process is important because of the substantial costs incurred in obtaining the recycled fibers. For recycling to succeed as an economically feasible process, these costs must be as low as possible while achieving the desired sanitary standards.
Among the microorganisms most difficult to kill are spore-forming bacteria. Spore-formers can survive the drying temperatures which are normally employed in a paper-making machine. If these spore-formers are present in the paper fibers that are supplied to the paper-making machine, the resulting paper and paperboard are likely to have substantially more than the 250 limit of colony-forming units per gram ("cfu/g").

Process for sanitizing post-consumer paper fibers using heat and hydrogen peroxide


The invention, in one embodiment, is a novel fracturing fluid composition comprising an aqueous metal hydrated galactomannan gum, buffered to a pH of from about 9 to about 11. In another embodiment, a method of fracturing a formation is disclosed, the method being characterized by the use of the compositions mentioned.

In the process of recovering hydrocarbon values from subterranean formations, it is common practice to treat a hydrocarbon-bearing formation with a pressurized fluid to provide flow channels, i.e., to fracture the formation, or to use such fluids to control sand to facilitate flow of the hydrocarbons to the wellbore. Well treatment fluids, particularly those used in fracturing, typically comprise a water or oil based fluid incorporating a thickening agent, normally a polymeric material. The thickening agent helps to control leak-off of the fluid into the formation, and aids in the transfer of hydraulic fracturing pressure to the rock surfaces. Primarily, however, the thickening agent permits the suspension and transfer into the formation of proppant materials which remain in the fracture or sand when the hydraulic pressure is released, thereby holding the fracture open or stabilizing the sand.
Typical polymeric thickening agents for use in such fluids comprise galactomannan gums, such as guar and substituted guars such as hydroxypropyl guar and carboxymethylhydroxypropyl guar. Cellulosic polymers such as hydroxyethyl cellulose may be used, as well as synthetic polymers such as polyacrylamide. To increase the viscosity, and, therefore, the proppant carrying ability of the fracturing fluid, as well as increase its high temperature stability, crosslinking of the polymeric materials employed is also commonly practiced. Typical cross linking agents comprise soluble boron, zirconium, and titanium compounds.
By necessity, well treatment fluids are prepared on the surface, and then pumped through tubing in the wellbore to the hydrocarbon-bearing subterranean formation. While high viscosity, thickened fluid is highly desirable within the formation in order to transfer hydraulic pressure efficiently to the rock and to reduce fluid leak-off, large amounts of energy are required to pump such fluids through the tubing into the formation. To reduce the amount of energy required, various methods of delaying crosslinking have been developed. These techniques allow the pumping of a relatively less viscous fluid having relatively low friction pressures within the well tubing with crosslinking being effected near or in the formation so that the advantageous properties of thickened crosslinked fluid are available at the rock face.
One typical delayed crosslinking well treatment fluid system comprises borate crosslinked galactomannan gums such as guar or hydroxypropyl guar. The galactomannan polymers, which may be provided as a solid or as a suspension in a hydrocarbon, hydrate in neutral or acidic solution to form a gel. Under these conditions, i.e., pH of 7 or lower, no crosslinking of guar or hydroxypropyl guar will occur with borate ion. To effect borate crosslinking of guar and hydroxypropyl guar, the pH must be raised to at least 9.0. The requirement to raise the pH to this level has been exploited to delay the crosslinking of the galactomannan gums by borate ion.
The practice of delaying crosslinking of thickening agents in such fluids, however, presents its own set of difficulties. Thus, sophisticated techniques must be employed to adjust the pH of the fluid at the proper location, i.e., in or near the formation. U.S. Pat. No. 5,259,455, for example, describes the practice of controlled dissolution of MgO in a fracturing fluid to provide such pH adjustment. To be able to operate effectively where formation temperatures are above 200.degree. F., the patent discloses additives to prevent the magnesium precipitation which would lower the pH of the system.
An alternative approach to downhole pH adjustment would be some reduction of the concentration of the thickening agent in the well treatment fluid, with crosslinking being accomplished or being only slightly delayed, the reduced loading thereby reducing the friction penalty. However, reduction of the thickening agent concentration (i.e., use of a lower concentration) in such fluids has not been practiced to any significant extent because of a long-established belief by those skilled in the art that minimum levels of loading of the thickening agents mentioned are required for effective or sufficient crosslinking. In the case of guar, for example, this concentration has been considered to be about 17 pounds of guar per one thousand gallons of aqueous fracturing fluid. This belief was based on studies of the radius of gyration of the guar molecule and the theory that if the radius of gyration of two molecules in solution do not overlap, the molecules cannot be crosslinked to produce the type of gel required for reliable fracturing operations. As a general proposition, most well treatment solutions employed in the field utilizing crosslinking of the thickening agent prior to the invention have utilized concentrations of the delayed crosslinking thickening agents that are well above the level mentioned, and, typically, 30 pounds per 1000 gallons of liquid or greater are used.
Accordingly, a need has existed for a well treatment fluid, especially a fracturing fluid, that exhibits relatively low friction loss in the well tubing, while avoiding the difficulties associated with raising the pH at the proper time or location, and further avoids those difficulties associated with insufficient crosslinking. Further, there has existed a need for an effective fluid having reduced concentrations of thickening agent or agents, thereby reducing the costs of such solutions and improving the conductivity of the formations. Finally, there has existed a need for a method of treating or fracturing a subterranean formation characterized by use of a low cost fracturing fluid that is not dependent on precision pH adjustment downhole. The invention addresses these needs.

Metal ion crosslinked fracturing fluid and method


An analog-to-digital converter generates an output digital value equivalent to the difference between two analog signals. The converter forms part of a set of converters. The converter receives a first analog signal and a second analog signal (Vreset, Vsig) and a ramp signal (Vramp). A clock is dedicated to the converter, or a sub-set of converters. A control stage enables a first counter based on a comparison of the ramp signal with the first analog signal and the second analog signal. The converter can be calibrated by at least one reference signal (Vref1, Vref2) which is common to the set of converters. A-to-D conversion can include a first A-to-D conversion stage which determines a signal range, selected from a plurality of signal ranges, and a second A-to-D conversion stage which determines an M-bit digital value equivalent to the difference between the first and second analog signals by comparing the signals with a ramp signal, with the ramp signal having the signal range determined by the first analog-to-digital conversion stage.

Imaging sensors comprise an array of unit elements (pixels). The array of pixels is exposed to radiation during an exposure period and, subsequently, the signal value of each pixel is read from the array. The array can be a one dimensional array (linear sensor) or a two dimensional array (area array) with pixels arranged in rows and columns.
FIG. 1 shows the typical architecture of a CMOS imaging sensor. Impinging photons are converted into charges in the pixel array 10 and are accumulated during a certain integration period. Typically, the pixels are selected row by row for readout of their signals. A typical four transistor (4T) pixel is shown in FIG. 2. The pixel includes a photodiode PD, a transfer gate to transfer the charges in the photodiode to the floating diffusion FD, a reset transistor M1, a source follower M2 and a row selection transistor M3. The reset transistor M1 is used to reset the floating diffusion FD to a known state before transferring charge from the photodiode PD to it as is known in the art. The source follower M2 converts the charges stored at the floating diffusion FD into an electrical output voltage signal at the column bus. The useful signal outputs of a pixel are analog voltages representing: (i) the reset signal level Vreset and (ii) the signal level Vsig that is generated after charge transfer from the photodiode. The final signal that represents the amount of photons impinged onto the pixel is the difference signal between these two signals. In the sensor of FIG. 1, there is sample and hold circuitry 15 associated with each column of the array. During the process of reading the array, the sample and hold circuitry 15 for each column stores the two signal values (Vreset, Vsig) for a pixel in a selected row. The two signals (Vreset, Vsig), or the difference between these signals (Vreset−Vsig), must be converted from an analog value to a digital value. In FIG. 1 the analog-to-digital conversion is performed by a single ADC 16 in the output stage of the array and this single ADC 16 is used, on a time-shared basis, by the column circuits. In turn, signal values are transferred from each of the column circuits to the ADC 16 and converted to digital form.
FIG. 3 shows an alternative approach. Analog-to-digital conversion is performed, in parallel, in each column of the array. The single-slope ADC comprises a ramp generator 20 and a synchronous counter 17. Each column has two data latches 18 and a comparator 19. A ramp signal is applied to each of the columns circuits. The ramp signal is distributed to all columns. The counter 17 is incremented in synchronism with the ramp signal such that, at any point in time, the counter 17 provides a digital representation of the analog value of the ramp signal output by the ramp generator 20. The comparator 19 in each column compares the level of the input signal (Vreset or Vsig) against the gradually changing ramp signal. When the ramp voltage reaches the value of the input signal voltage, the comparator 19 output changes state and latches the digital code of the counter into a first memory 18. Afterwards, the same process is repeated for the other of the signals (Vreset, Vsig) and the code is latched into a second memory 18. The difference in digital codes is then sent to the output of the sensor.
A refinement of this arrangement is described in U.S. Pat. No. 7,088,279 and U.S. Pat. No. 7,321,329 and shown in FIG. 4. The circuitry associated with each column is provided with a dedicated counter 31 which is able to count in a downwards direction and in an upwards direction. When converting the reset signal Vreset, the counter 31 counts down until the ramp signal reaches the reset level. The direction of counting of the counter 31 is then switched. During the next ramp signal, the counter 31 counts up until the level of the light induced signal Vsig is reached. The technique is depicted in FIG. 5. This architecture has some advantages compared to the conventional architecture. In the conventional architecture, the code generated by counter 17 needs to be distributed over the columns. Column-to-column variations of clock skew, which cause conversion error, are generated when a high-speed clock is used. Both reset level and signal level include offset noise from pixel, column circuitry and comparator, the ADC automatically performs the calculation of the difference between the reset and signal values and no additional subtraction circuitry is required. Ripple counters can be used in this architecture because it is unnecessary for them to be synchronized with the high-speed clock. Column-to-column variations of clock skew and counter delay which cause A/D conversion error are corrected for.
It is desirable that the analog-to-digital conversion occurs as quickly as possible. The rate at which the ADC can operate is limited by several constraints. A significant constraint is the period of the ramp signal against which the analog reset level and signal level are compared. The gradient of the ramp signal Vramp signal can be increased but, for a given resolution (number of bits), it is necessary to proportionally increase the frequency of the master clock that is distributed to the counters in the column processing units. In practice, there is a limit to the clock frequency that can be achieved.
The present invention seeks to provide an alternative way of performing analog-to-digital conversion.

Analog-to-digital conversion in pixel array


Instrument and systems for applying ablative energy to epicardial tissue via a subxiphoid access surgical approach. The instrument has a head assembly sized and shaped for a subxiphoid surgical approach to a patient's heart and defines a contact face. The head assembly includes a paddle body, a first ablation electrode, and a second ablation electrode. The ablation electrodes are coupled to the paddle body in a spaced apart, spatially-fixed fashion. The ablation electrodes are exteriorly exposed at the contact face. A tubular member extends from the head assembly and maintains wiring connected to the ablation electrodes. The instrument is manipulable to locate the contact face on epicardial tissue of a patient's heart via a subxiphoid surgical approach, such as between the left and right pulmonary vein junctions of the posterior left atrium.

Atrial fibrillation is a common cardiac condition in which irregular heart beats cause a decrease in the efficiency of the heart, sometimes due to variances in the electrical conduction system of the heart. In some circumstances, atrial fibrillation poses no immediate threat to the health of the individual suffering from the condition, but may, over time, result in conditions adverse to the health of the patient, including heart failure and stroke. In the case of many individuals suffering from atrial fibrillation, symptoms affecting the patient's quality of life may occur immediately with the onset of the condition, including lack of energy, fainting, and heart palpitations.
In some circumstances, atrial fibrillation may be treated with drugs or through the application of defibrillation shocks. In cases of persistent atrial fibrillation, however, surgery may be required. The surgical procedure originally developed to treat atrial fibrillation is known as a "MAZE" procedure where the atria are surgically cut apart along specific lines and sutured back together. While possibly effective, the MAZE procedure tends to be complex and may require highly invasive access to the thorax. In order to reduce the need to open the atria, thermal ablation tools have been developed to produce lines of inactive tissue along the heart wall that mimic the MAZE procedure. This is most commonly done using radio frequency (RF) ablation devices to ablate and electrically isolate tissue that may be responsible for the improper or electrical conduction that causes atrial fibrillation.
A variety of cardiac ablation devices and methods are currently available for treatment of atrial fibrillation and other arrhythmias. With some systems, endocardial tissue is contacted and ablated, for example via a catheter-based ablation instrument. Conversely, epicardial tissue can be ablated. Conventionally, cardiac surgeons access the epicardial tissue via a standard sternotomy. More recently, certain atrial fibrillation treatment procedures have been advanced that entail ablating small segments of epicardial tissue on a minimally invasive basis, such as via a single or bilateral thoractomy approach. For example, the junctions of pulmonary veins with the left atrium have been identified as being a common area where atrial fibrillation-triggering foci reside. For many patients, then, atrial fibrillation can be effectively treated by ablating only a portion of the complete MAZE pattern, such as at the pulmonary vein/left atrium junction. More particularly, a viable cardiac arrhythmia treatment technique entails ablating an epicardial lesion into the posterior left atrium around or circumscribing the left pulmonary veins and another epicardial lesion encircling the right pulmonary veins. These island ablation lesions can be formed on a minimally invasive basis via bilateral thoractomy using clamp-type ablation instruments, for example a surgical ablation device available under the trade name Cardioblate® Gemini™ available from Medtronic, Inc. While well-accepted, the bilateral thoractomy surgical approach may require the surgeon to perform various additional procedures, such as dissection of pericardial reflections, in order to laterally access the posterior left atrium ablation site(s). Additionally, while the pulmonary vein island ablation represents only a small portion of a complete MAZE procedure, additional epicardial lesions along the left atrium may be beneficial to prevent re-entry of an unwanted sympathetic pathway.
In light of the above, a need exists for systems and methods of making epicardial lesions on selected cardiac locations on a minimally invasive basis, such as along the posterior left atrium via a subxiphoid surgical approach.

This patent is subject to a terminal disclaimer.

Subxiphoid connective lesion ablation system and method


Advertisements in broadcast television programming are digitally replaced with different ads prior to viewing. Replacement can occur in time and/or place shifted content, and can be used to promote a particular advertisement that the viewer has not yet seen, thereby improving the reach of the ad without oversaturation. Data reporting by the playback devices is collected in a database of viewed ads. The information in the database can be used to refresh previously-viewed ads, to increase saturation of particular ads, to replace previously-broadcast but no longer relevant ads, or for other purposes as desired.

As television receivers, media players and other media playback devices become increasingly sophisticated, additional functions and features have been enabled. Many modern media devices are now capable of enhancing the viewer's access to media content through place and time shifting, video on demand, local and remote storage digital video recorders and/or any number of other features, to provide just a few examples.
As player capabilities become more sophisticated, advertisers are facing increasing challenges in providing advertising content that is engaging and relevant to a wide number of viewers. While advertisers often attempt to improve the reach and frequency of their advertisements, in practice this can be extraordinarily difficult, particularly as digital video recorders (DVRs) and similar technologies make ad skipping easier than ever.
While it would be desirable to replace ads that are stored in DVR content and/or to perform other actions that would improve the reach and frequency of various digital ads, this can be very difficult to implement in practice. Amongst the challenges that are encountered, it can be very difficult for a cable, direct broadcast satellite (DBS) or other content distributor to know in advance when certain commercials will be run, making it very difficult to place identifiers or the like in the actual broadcast content itself. Conventional electronic program guides, for example, typically provide information about programming schedules, channel lineups and the like, but do not typically include detailed information about the specific content components of the broadcast, particularly the timing and identities of commercials that may be present in the broadcast stream. Moreover, due to the nature of live broadcasting, it is not always possible to know in advance where the ads will be located in the program stream, or what ads will be run. During a live broadcast of a sporting event, for example, it is very difficult to predict when the commercial breaks will occur, or even how many advertisements will run during the course of the program. It is extraordinarily difficult to predict the actual commercials that will be broadcast before they actually appear in the program stream. This difficultly is compounded by the large number of different channels and programs where an ad may (or may not) appear.
Moreover, the distributed nature of broadcast television makes ad replacement or enhancement technologically difficult to implement. A typical broadcaster or other content distributor source often has many thousands or even millions of subscribers, each receiving their own copies of the broadcast content on their own receiving equipment. Modern television viewers frequently time and/or place shift their viewing using a local or remote storage DVR, thereby leading to thousands (or millions) of separate and distributed copies of the same content, each stored in a different location, and potentially recorded with slightly different parameters (e.g., start and end times). Further, many viewers receive slightly different broadcasts of the same content (e.g., different regional broadcasts), thereby leading to content variations even amongst customers of the same content distributor. These variations amongst the many different copies can make content enhancements (such as ad refreshment) extraordinarily difficult to implement using current technologies. Ad replacement or refreshment is especially difficult after the program has been broadcast when the program is stored in any number of different video recorders that are spread across a wide geographic area.
It is therefore desirable to create systems, device and automated processes to reliably identify and refresh advertisements in television programming even after the content has been broadcast. These and other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background section.

Automated replacement of video program content


The present invention provides a leaning vehicle comprising a leaning frame (1), a front suspension assembly (2), an undercarriage element (3), a rear suspension assembly (4) and a motor (10), wherein the leaning frame (1) comprises a straddle seat (5) and a hand steering element (6), the hand steering element operatively connected to the front suspension assembly (2); the undercarriage element comprises a front section (7) and a rear section (8), and is connected to a suspension connecting element (9); the front suspension assembly (2) comprises two ground engaging members (13) and at least one shock absorber (20), and is connected to the leaning frame (1) and the suspension connecting element, such that the ground engaging members (13) of the front suspension assembly will tilt in the same direction as the leaning frame; the rear suspension assembly (4) comprises at least one rear ground engaging member (23) and is connected to the rear section (8) of the undercarriage element; wherein the leaning frame (1) is pivotally connected to the undercarriage element (3), such that the leaning frame and the two ground engaging members may tilt in a sideways direction relative to the undercarriage element, the rear ground engaging member and the rear suspension assembly.

Leaning vehicles (also known as tilting vehicles) having 3 or 4 wheels are well known. A common feature of such vehicles is the presence of two front wheels connected such that both front wheels lean in the same direction when the leaning vehicle is tilted in a sideways direction. Leaning vehicles have a number of advantages in that two front wheels increase the braking efficiency, i.e. reduced stopping length, and further in that the risk of front wheel slip is substantially reduced. The latter is a common cause of motorcycle/scooter accidents.
Balancing the weight of vehicles during low speed maneuvering, especially those with a high Centre of Gravity (CoG), is a known problem for leaning vehicles having 3 or 4 wheels. Leaning vehicle with 3 or 4 wheels will typically have a higher total mass than a comparable 2-wheeler (motorcycles/scooters), and the problem of weight balancing is thus even more noticeable.
The weight balancing problems are also applicable to snowmobiles and snow bikes having a pair of front skis and a rear belt drive.
It is also desirable to add more functionality to such leaning 3 or 4 wheel vehicles. Such functionality includes weather protection like a front window and safety by adding a rollover protection/cage. This may in the largest extent of the solution be a fully enclosed cabin providing a driver/passenger compartment to the vehicle. A major problem with such extensive additions is an even higher CoG, and consequently, an increased problem of balancing the weight of the vehicle.
Although the weight balancing problem is more pronounced for large and/or enclosed leaning vehicles, it is also relevant for small and open 3 or 4 wheelers.
A further issue with leaning vehicles, is that the presence of three or four rotating wheels, as opposed to two in a common motorcycle, provides an increased resistance towards change of the tilt angle of the vehicle due to the increased total moment of inertia.
WO 2005/002957 A1 discloses a leaning vehicle comprising footboards on which the weight of the tilting part of the vehicle may be balanced. However, the force needed to balance the total weight is quite high and the use of footboards is not an ideal solution for most people.
The present invention provides a leaning vehicle, wherein at least some of the disadvantages of present leaning vehicles are avoided or alleviated.


A rowing apparatus having support tubing that extends over the gunnels of the canoe, and to which the oars are mounted, is angled upwardly to provide added clearance in choppy waters. The elongated track support to which the seat and the support tubing are mounted is provided with repositionable mounting brackets that enable the height from the floor of the elongated support member to be adjusted within a range of several inches to maintain a suitable center of gravity for a wide range of weather conditions. In this manner the rower is capable of maximizing the transfer of power through the rowing apparatus, and still maintain the stability of the canoe. Since wilderness rowing is a physically demanding activity, the rowing apparatus is easily adaptable for use as a training device, permitting the user of the apparatus to use the same device in their home for exercise and training purposes that they can also use in their canoe on an actual wilderness rowing expedition.

1. Technical Field
The present invention relates generally to rowing mechanisms used in small watercraft. In particular, the invention relates to rowing machines using human power that may be mounted within canoes or rowing sculls, and which also may be used separately for physical conditioning.
2. Background Information
Rowing machines for exercise in the home and gym have been known for a long time. Similarly, albeit more recently, rowing mechanisms for use in canoes or other small watercraft have also been commercialized. One of the central advantages of these mechanisms in small watercraft is that, by using the strength of the legs and both arms, combined with the leverage provided by an oar pivoting at an oar lock extended outwardly from the side of the canoe, they more efficiently convert the energy generated by the human body for propelling the boat over the water.
Initial iterations of this type of mechanism have proven effective, although not particularly sturdy. When used in actual rowing conditions, especially over extended periods of time and over great distances, the construction of these machines has proven to be unreliable and not sturdy enough to handle the rigors of demanding use.
It has also been learned that certain adjustments made to the configuration of components of the apparatus result in significant improvements in performance. For example, in waters with large waves, the outriggers to which the oars are mounted on prior art devices have proven to be too low for practical use. Furthermore, the rolling mechanism of the seat has not been very durable, resulting in breakdowns, which can be a significant problem if the rower is in the wilderness and unable to summon assistance. It is also helpful to permit the position of the foot rests to be adjustable relative to the outriggers to which the oars are mounted for rowers of different sizes.
Prior rowing mechanisms have also added greatly to the weight of the canoe or other small watercraft. When portages of great distances are contemplated for the canoe, the added weight can be a significant difficulty for the person carrying the load.
The rowing apparatus of the present invention overcomes difficulties described above and affords other features and advantages heretofore not available.


A pneumatic cylinder with a piston rod movable to fully extended, intermediate and fully retracted positions. The cylinder may have a first head engaging one end of a first tube with a first piston slidably received therein, an intermediate connector engaging the other end of the first tube and one end of a second tube with a second piston slidably received therein, and a second head engaging the other end of the second tube. The piston rod may be attached to the second piston for movement therewith and extend through the intermediate connector, first piston, first tube, and the first head to the exterior thereof.

A three position pneumatic or air cylinder assembly in the form of two separate opposed cylinders each having a piston rod attached to a piston and providing a first position with both piston rods fully retracted, an intermediate position with one piston rod fully retracted and the other piston rod fully extended and a fully extended position with both piston rods fully extended is previously known. These back-to-back cylinders may also provide two intermediate positions if the piston rods have different stroke lengths. With these back-to-back cylinders, the cylinder casings may move relative to a fixed reference point. Another form of a three-position pneumatic cylinder is known with first and second cylinders in series and each having a piston rod attached to a piston with the first piston rod of the first cylinder extending into the casing and a tubular second piston rod of the second cylinder and engageable with the second piston. With this series arrangement, both the first and second piston rods may be in a fully retracted first position, the second tubular piston rod may be moveable to a partially extended position to provide a second intermediate stroke position, and in a third fully extended position both the first piston and rod and the second piston and rod are in their fully extended positions.


An electrostatic discharge noise suppression method and system is disclosed for electronic devices, particularly those connected to data buses. Electrostatic discharge protection is provided by breaking high-frequency ground loops by inserting common mode inductors where they can be most effective-in the DC power supplies themselves, in the DC power connections, or just behind the DC connector in the electronic devices. Saturation of the cores of the common mode inductors is prevented in a preferred way by equalizing supply and return currents in the common mode inductors and by preventing DC ground currents from flowing in a chassis between the power supply and the electronic device.

The invention is directed to a noise suppression method and circuit for an electronic device for suppressing electrostatic discharge (ESD) noise pulses which affect the electronic device and data buses connected to these devices.
Most of the problems encountered with ESD are caused by electrostatically charged human bodies touching the electronic devices, either its chassis or external cables, causing discharge currents to flow towards ground. For example, hard to solve problems occur when tape cassettes, cartridges or diskettes are inserted into data storage devices. These devices are usually mounted as subassemblies in the computer chassis.
During a discharge event, tens of amperes can flow in less than a nanosecond. An electromagnetic wave will propagate towards ground on the chassis and the cables leaving the device. Due to the very high frequencies involved, much of the prior art ESD problem solving has been directed towards proper shielding and grounding of the electronic devices. The coupling mechanisms can be divided into four parts: Direct conduction, secondary arcing, electric field, and magnetic field couplings. To solve the problems associated with electric field coupling to the circuits, it is recommended not to float the signal grounds with respect to the chassis ground or not to provide an external ground connection independent of the chassis ground to the electronic devices. A multiple grounding scheme is therefore often used for the devices inside the chassis. To solve the problems with magnetic coupling, shielding is usually recommended. However, for cables used for data buses, problems arise due to this multiple grounding scheme. When the signal ground of, say, both ends of a data bus cable is connected to the chassis, a ground loop is formed. Noise currents can then flow if the chassis potential is different at the two ends or if voltages are induced in the loop due to magnetic coupling. For a discussion of the prior art, see Ott, H. W., "Noise Reduction Techniques in Electronic Systems", 2nd ed. John Wiley & Sons, New York, 1988; and Hewlett Packard Course No. HP 11949A; "Designing for Electromagnetic Compatibility", Application Support Division, Mountain View, Calif., U.S.A., 1989.
It is known in the art that ESD protection of the data buses can be obtained by using ferrite tubes or clamped ferrite pieces around the signal cables. See Murakami, Yuichi, JEE Journal of Electronic Engineering, Vol. 8, No. 174, July 1981, page 49, FIG. 8; and Hewlett Packard Course No. HP 11949A, supra.
The function of these ferrite components is then as a common-mode inductor.
The problem with these data bus protection schemes can be divided into two parts. First, due to the leakage inductance of the common mode inductors available, the high frequency components of the differential signal currents may also be attenuated if the common mode impedance is too high. It is therefore very difficult to obtain a good protection against noise. Second, the data buses typically consist of as many as 50 signal and ground wires and a common mode inductor for all these signal lines becomes very expensive. An alternative consists of using ferrite clamps around the cables, but even those tend to be expensive parts.
It can be also mentioned here that other types of usage exists for common-mode inductors. They can be used to prevent conducted radiated electromagnetic noise from leaving the devices via cables. See, for example, Siemens Aktiengesellschaft, "EMC EMI Suppression Components, Filters", Data Book 1987/88. For signal lines, the leakage inductance can also be utilized to limit the bandwidths of the differential signal waveforms transmitted on the cables.

Electrostatic discharge noise suppression method and system for electronic devices


A semiconductor memory structure includes a semiconductor layer, a conductive layer disposed over the semiconductor layer, a gate penetrating through the conductive layer and the semiconductor layer, and an interposing layer disposed between the gate and the conductive layer and between the gate and the semiconductor layer, wherein a pair of channel regions is formed in the semiconductor layer at two sides of the gate.

Recently, great progress has been achieved in development of semiconductor memory devices. Due to continuously increasing requirements for memory devices with mass capacity, integration density of memory cells in a memory device keeps increasing. Scaling the memory cell size and realizing high-density memory are eagerly needed for various applications such as internet of things (IoT) and mechanism learning. As critical dimensions of devices in integrated circuits shrink to the limits of common memory cell technologies, designers have been looking to techniques for stacking multiple planes of memory cells to achieve greater storage capacity, and to achieve lower costs per bit. A three dimensional (3D) memory array architecture has been realized by stacking several cells in series vertically up on each cell which is located in two dimensional (2D) array matrix. There is a continuous demand to develop improved semiconductor memory structures for satisfying the above requirements.

Semiconductor memory structure and device

TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.


The present application relates to processes for changing the composition of surfaces and the application of such processes. The process involves the introduction of a surface augmentation composition within an aerosol formed from a liquid precursor with bombarding particles in an ultrasonic shot peening apparatus.

Shot peening is a process whereby the physical nature of an existing device surface may be modified. In shot peening, solid particulate is propelled at high velocity by means of a carrier fluid either wet or dry, typically water and air respectively, so as to impact the surface of a target substrate typically a metallic substrate.
Shot peening has long since been established as a method to induce desirable stress properties in the surfaces of metallic devices wherein the impinging particles act as peening hammers causing a local plastic deformation at the surface rendering it less prone to cracking and corrosion. In addition to the significant pressures, large amounts of thermal energy, instantaneous temperatures as high as 1000° C. have been reported, are also generated locally at the surface in the vicinity of the impact. The limitation of shot peening processes involving the use of fluid streams to propel the shot particles to surfaces is that while shot may be recovered, large amounts of shot are required in the process itself. This places practical cost limitations on the quality of shot that can be used and a proportion of the shot used is consequently of irregular shape. The action of such irregular shot particles on surfaces can be abrasive in nature resulting in a degraded surface finish.
In addition shot peening nozzles are generally configured orthogonal to the surface so that the shot strikes the surface at a constant angle of incidence of close to 90°. As a result the resulting shot peened substrate surfaces are typically dimpled and uneven in texture.
Ultrasonic shot peening (Cheppe and Duchazeaubeneix, U.S. Pat. No. 6,343,495) has been developed as a means to circumvent these limitations. In this process shot is projected to the surface by means of a sonotrode. A sonotrode is a device that oscillates at ultrasonic frequencies and which impels the shot to the substrate surface. The sonotrode can be located in the bottom of a chamber such as a metal bowl. The rim of the bowl may contact the surface to be peened or the surface may form a wall or walls of a chamber that encloses the piece to be shot peened. This confinement of the shot means that much less shot is required as individual shot can repeatedly peen the work piece given that shot will continually rebound from the work piece and chamber walls back to the sonotrode from which it is again impelled to the work piece surface. The requirement for lower quantities of shot means that shot of higher material and geometry quality may be selected and a superior surface finish obtained. Additionally the random direction from which the shot impacts a work piece results in a surface less dimpled and less uneven in nature. Ultrasonic shot peening has largely been used for specialist applications and in particular for the work hardening of materials in the aerospace sector including for example turbine blades.
Shot peening and abrasive processes have been used extensively in surface science as a means to clean and condition surfaces in preparation for further treatments. A shot peening process is known for the simultaneous cleaning and painting of substrates (Kik and Schuurink—U.S. Pat. No. 4,517,248). The advantage being that the delay between cleaning and painting is eliminated minimizing re-oxidation of the cleaned metal surface prior to application of the paint. Gruss and Shapiro (U.S. Pat. No. 4,634,603) describe a process for the coating of printed circuit boards in which shot peening is employed to clean and condition the surface in preparation for subsequent coatings. A number of techniques have been disclosed which use shot peening or abrasive processes as a means to modify the surface chemistry/composition of metallic and other substrates by embedding desired solid material in the surface and these techniques may be broken into three distinct methodologies.
In a first methodology, a single type of single-phase solid particulate is used as the peening or abrasive media. In this method the shattered pieces of the particulate become embedded in the surface of the metal on impact. Such processes are mostly used to embed ceramic materials into a surface as the particles must have sufficient hardness size and mass to abrade or peen the surface. Examples include silica, alumina or calcium phosphate ceramics among others as, for example, disclosed in Arola and McCain (U.S. Pat. No. 6,502,442) and that of Kuo (U.S. Pat. No. 5,441,763).
The second methodology also involves the use of a single type of solid particle as the peening or abrasive media but the particles themselves are comprised of multiple components usually a hard component that gives the particle mass and density and a softer component that is desired to embed in or attach to the surface on impact. Examples are to be found in (Muller and Berger—US2004/158330; Bru—Maginez et al. U.S. Pat. No. 6,431,958; Hisada and Kihira U.S. Pat. No. 6,726,953; Omori and Kieffer—U.S. Pat. No. 6,015,586) and in the Rocatek™ bonding system for dental implants provided by 3M ESPE.
The third methodology is to employ a mix of different types of solid particulate media, a primary abrasive or peening material and a secondary material desired to embed or augment the surface in the same fluid stream so that they impinge the surface simultaneously. Examples of this process may be found in (Babecki and Haehner—U.S. Pat. No. 3,754,976; Chu and Staugaitis U.S. Pat. No. 4,552,784; Spears—U.S. Pat. No. 4,753,094; Vose—US20060089270; O'Donoghue. et al.—WO2008033867, O'Donoghue et al—US WO2009112945, where such processes are claimed to modify the surface composition of a variety of substrates with a number of materials including plastics, ceramics and metals. WO/2008/033867 teaches the use of grit blasting for the impregnation of metal oxide layers with solid particles delivered to the surface during a standard grit blasting treatment, the disruption caused to the surface oxide by the abrasive action allowing the smaller/softer solid particulate to become entrained in the oxide as it reforms.
Recently a fourth methodology for augmenting the surface of substrates, as detailed by Haverty and Kennedy—WO/2009/050251 (, has been described. This method involves atomising a liquid based precursor coating composition to form an aerosol, which is directed to the surface of the substrate in conjunction with a stream of hard, solid particles carried to the surface in a gas that may be of irregular shape (grit) but are more preferably of regular spherical shape (shot). In this process the collision energy released by the impacting shot mediates the transformation of the precursor composition into a well-adhered coating. This process solves problems associated with the prior art because the species augmenting the surface chemistry is not restricted to solid materials alone, the flow of augmenting species to the surface can be controlled precisely and those materials such as polymers particles that are typically prepared as colloidal suspensions can be used in the process. Both of these technologies suffer from the same limitation of regular shot peening processes with respect to quantities of shot used and consequently there exists the need for an improved process.

Processes and apparatus for surface modification


Provided is an unobtrusive client verification system with one verification devices having processors that are configured to receive a first request from an unverified client device, generate a random number in response to receiving the first request from the unverified client device, define a set of expressions as a browser challenge problem that evaluates to an answer specified by the random number, encrypt the answer within an answer token, provide the browser challenge problem with the answer token to the unverified client device, receive a second request with a solution to the browser challenge problem and the answer token from the unverified client device, and verify the unverified client device in response to the solution matching the answer that is decrypted from the answer token provided with the second request.

CAPTCHA is a form of obtrusive client verification that requires human interaction. CAPTCHA and/or other obtrusive client verifications may be used to verify that network requests and/or data originate from a valid user as opposed to a bot.
Browser challenges are a form of unobtrusive client verification that do not require human interaction. To perform a browser challenge, a server may send a problem in response to a request or data from a client. The server may verify that the client is running a valid browser instance, and is therefore a valid user and not a bot, that simply generates traffic, upon receiving a correct answer to the problem from the client.
Browser challenges may be subject to replay attacks. Specifically, a server or platform may have a finite set of problems that are issued as the browser challenges. A replay attack may involve using one or more client devices to gradually obtain each of the problems, and to generate the correct answers for the finite set of problems issued by the server or platform. The answers may then be distributed across a botnet. The botnet may be configured with simple logic that maps each answer to a corresponding problem. The botnet may then able to thwart the protections afforded by the browser challenges by simply replaying the answers to the problems issued by the server or platform rather than solving the problems.

Systems and methods for distributed, stateless, and dynamic browser challenge generation and verification


A package for storing and/or shipping discs has at least one section with a first panel, a second panel and at least one intermediate panel, the intermediate panel being positioned between the first panel and the second panel, where the first and second panels each include at least one opening for receiving a disc and the intermediate panel is solid in at least the area between the first and second panels below the openings where the discs are inserted. The package includes a fastener between the second panel and the intermediate panel positioned above the disc receiving opening on the second panel and a fastener between the first panel and the intermediate panel at a terminal edge of the first panel above the disc receiving opening on the first panel.

Removable data storage media including floppy discs and the like, are used for recording and playing back data such as audio, video and computer related or machine-readable data. Recent advances in technology have dramatically increased their data storage capacity, while reducing their overall physical dimensions and weight. Optical discs are one type of data storage media which utilize optical technology for managing and storing data. Optical discs are available in several formats including, but not limited to, minidisks, compact discs ("CDs"), digital video discs ("DVDs") and the like. Their large data storage capacity and compact size have made optical discs highly preferred over other types of data storage media including magnetic recording tape. The performance of these optical discs, however, can be adversely affected by minor distortions in the disc surface cause by abrasions, debris, cracks and the like. Such distortions can cause data loss or degradation in the affected optical disc.
To minimize data loss and physical damage, optical discs are typically packaged in rigid plastic containers or boxes. However, such containers are usually bulky, heavy, and prone to breakage. Other optical disc are packaged in flimsy paper sleeves that provide little or no protection against physical damage from impact or stress, or must be placed into bulky packing made from stiff paper or paperboard in order to reinforce the packaging.
Accordingly, there is a need for a package that can provide convenient and economical storage and display of discs such as optical data storage media (e.g., CDs, minidisks, DVDs and the like) that can be easily formed from a unitary blank, preferably from a rigid, foldable material.
A package that has helped fill this need is shown and described in U.S. Pat. No. 6,938,759. However, the package described therein utilizes a complex arrangement with slots and flaps interior to the opening for receiving the discs, requiring a number of cuts and perforations in the blank. Additionally, although the arrangement avoids contact of two opposed discs at the point that the second disc is being inserted, the fully inserted opposed discs can contact each other.
There is therefore a further need for a package for storing discs that is more efficient to manufacture, easier to use and friendly to the environment which has the capability of storing the discs in back to back relationship for enhanced functionality.


A receiver circuit processes a received signal to determine information regarding a guard interval therein. The receiver circuit typically forms digital samples from the received signal; generates a correlation function with peaks at positions that are determined by the size of the guard interval and a position of the guard interval within the received signal. The receiver circuit includes one or more comb filters, each corresponding to a possible guard interval size, each receiving a series of locations at which the correlation function exceeds a predetermined threshold, and each producing an output that provides information about the guard interval size and/or position. This advantageously allows the receiver circuit to determine the guard interval size quickly, for example, even in the case of received signals with relatively low signal-noise ratio.

1. Field of the Invention
This invention relates to a communication receiver, in particular for receiving signals in which a portion of a transmitted signal forms a guard interval.
2. Description of Related Art
The European DVB-T (Digital Video Broadcasting-Terrestrial) standard ETS 300 744 for digital terrestrial television (DTT) uses Coded Orthogonal Frequency Division Multiplexing (COFDM) of transmitted signals, which are therefore grouped into blocks and frames.
It is necessary to transmit the DTT signals over transmission paths which are of uncertain quality. In particular, the area close to the transmission path may include objects such as tall buildings, which cause reflections. That is, a signal may be received at a receiver twice, once on a direct path from the transmitter, and then, after a short delay, as an indirect reflected path. As is well known, this can cause inter-symbol interference (ISI) in the receiver. To reduce this problem, DVB-T COFDM signals include a cyclic prefix guard interval to each active symbol. Specifically, the end portion of the active symbol is repeated before the current active symbol.
These cyclic signals must be correctly removed before demodulation, or the demodulation performance can be seriously degraded. Before the cyclic signals can be removed, it is necessary to know the duration of the guard interval. This is not a constant value, because the presence of the guard interval reduces the efficiency with which the transmission channel can be used, and so it is advantageous to vary the size of the guard interval to be the minimum allowed by the conditions.
The receiver must therefore include a mechanism for determining the size of the guard interval. The chosen mechanism must be robust enough to deal with noisy signals, and with signals which suffer from multipath and co-channel interference.

Guard interval analysis method and apparatus


The present disclosure provides a cleaning system and a cleaning apparatus. The cleaning system includes a cleaning apparatus and a robot. The robot includes at least one robot arm. The cleaning apparatus includes at least one adaptor mechanism and a cleaning mechanism. The adaptor mechanism connects the cleaning mechanism to the robot arm. By controlling robot arms of the robot, the cleaning mechanism of the cleaning apparatus performs cleaning operations for platforms. The cleaning system achieves continuous and efficient cleaning effects, and operates object cleaning in diverse manners.

The present disclosure relates to a field of cleaning technology, and particularly to a cleaning system and a cleaning apparatus.
During manufacturing of liquid crystal displays (LCDs), there are many steps that require manufacturing equipment to include a platform, on which glass substrates are disposed, to provide a planar level. For example, coaters include a platform in order to have glass substrates be uniformly coated, and pre-baking equipment include a platform to have glass substrates be heated evenly. However, impurities and foreign matters falling on platforms affect the planar level provided by platforms. For instance, height of impurities formed on platforms affect desired thickness of coated photoresist, which is coated on glass substrates disposed on platforms. This results in a phenomenon, called mura (uneven brightness), which often occurs on display panels. Therefore, a platform is one of various major components that is required to be cleaned in each periodic maintenance.
Platforms have to be regularly cleaned in order to ensure that cleanliness of platforms can prevent abnormality of products from happening. According to prior art, platform cleaning operation is executed manually. Manual cleaning operation is performed by directly contacting products, and visual checks of cleaned products can be conducted at the same time while manual cleaning operation is performed, therefore manual cleaning operation achieves acceptable cleaning effects. In addition, under cost considerations, automatic cleaning equipment is not developed and used. However, manual cleaning operations still have two disadvantages: (1) it is difficult for manual cleaning operations to prevent impurities carried by cleaning operators from falling on platforms to cause secondary pollution; and (2) manual cleaning operation is extremely complicated, cleaning operators need to be cleaned from head to foot first before entering the equipment, and cleaning range is smaller and thus cleaning efficiency is low.
Therefore, there is a need to provide a technical solution in order to solve the problems existing in prior art, where platforms cannot be cleaned automatically.

Wuhan China Star Optoelectronics Technology Co., Ltd.


An MRI system coil insert 2 for use within a bore B of a main MRI system 1, the coil insert 2 comprising at least one gradient coil, for creating a spatially varying magnetic field along a respective axis and being arranged to be electrically driven at an ultrasonic frequency.

MRI (Magnetic Resonance Imaging) systems are widely used for imaging subjects and also acquiring spectral information in the case of MRSI (Magnetic Resonance Spectroscopy Imaging). An MRI system typically comprises a magnet arrangement for creating a large static magnetic field B0, a set of radio frequency coils or antennas for generating an alternating magnetic field B1 and collecting a magnetic resonance signal (that is to say acquiring magnetic resonance data), and a set of gradient coils to allow spatial encoding on the B0 field to enable tomographic imaging. Further in the case of MRSI the gradient coils are also used to allow spectroscopic encoding.
Spatial encoding of the magnetic resonance signals is typically achieved by fast switching of three magnetic field gradients (X, Y, Z) created by gradient coils located around the scanner bore in which the subject to be investigated will be located.
Typically, in existing systems, the gradient coils are driven at in the range of 0-10 kHz. As the gradient coils are driven in the auditory range (20 Hz-20 kHz) considerable efforts have been made towards reducing the noise caused by the Lorenz forces induced in, and by, the switching gradients. Such methods include using material to dampen the noise which is created.
To boost MRI spatiotemporal resolution the gradient system can be driven "faster" and "stronger". That is to say with higher gradient slew rates (T per m per s) and higher gradient strengths (mT per m). At present gradient performance can be chiefly limited by uncomfortable peripheral nerve stimulations (PNS) induced by too fast switching of a strong magnetic field gradient. Switching of the gradients induces electric fields and currents in conducting tissue, such as muscles and nerves, and may result in nerve depolarisation and ultimately nerve stimulation.


A method for cleaning a metal plating tank is provided herein. In accordance with the method, the tank is exposed to a first acid (103), after which the tank is exposed to a second acid in the presence of a first oxidizing agent (107).

The use of copper interconnect technology has become widespread in the semiconductor industry, due to the increased circuit speed copper provides compared to older technologies. At the same time, the use of lower capacitance dielectric materials, commonly referred to in the art as low dielectric constant or "low k" materials, has become more common to provide insulation around the interconnect wiring of semiconductor devices. While the use of interconnect materials such as copper allows signals to travel faster through a device, the use of low-k materials decreases the capacitance factor of the dielectric material surrounding the interconnect. This further increases the speed at which signals can travel across the interconnect, because the signals have less interference with each other.
It is well known that copper has a much more pronounced tendency to diffuse into dielectric materials than older interconnect materials such as aluminum. This tendency degrades the dielectric constant of dielectric materials. Hence, in order to integrate the use of copper with dielectric materials, barrier films such as Ta, TaN and the like are used around the interconnect to prevent the diffusion of copper into the surrounding dielectric materials. Materials such as CoWB and CoWP are used to cap copper for similar reasons and also to enhance device reliability by increasing electromigration resistance. In the formation of these types of barrier films, a very selective deposition of the barrier films is required.
Electroless deposition has emerged as a desirable process for forming doped cobalt barrier films. In addition to having the requisite selectivity, certain electroless films such as CoWB do not require catalytic activation for deposition processes, and may be implemented at sufficiently low temperatures. A description of the use of an electroless deposition process in forming barrier films may be found in commonly assigned U.S. Pat. No. 6,924,232 (Mathew et al.).
Despite the significant advantages of the electroless process in forming doped cobalt barrier films, the commercial implementation of this process is beset by certain challenges. In particular, in practice, it is frequently found that the plating bath life in the electroless process is much shorter than should theoretically be the case. This necessitates frequent bath replacement and costly interruptions to the semiconductor fabrication process, and is also undesirable from an environmental perspective.
There is thus a need in the art for an electroless plating process that overcomes the aforementioned infirmities. In particular, there is a need in the art for a method for implementing an electroless plating process that provides for a longer bath life. These and other needs may be met by the devices and methodologies described herein.

Method for cleaning electroless process tank


Optical signal produced by a semiconductor electroabsorption modulator is passed through an optical discriminator to increase the optical and electrical modulation response of the device and decrease the output chirp for distortionless transmission through dispersive optical fiber.

This invention relates to optical signal processing and transmission in fiber-optic communication systems.
Fiber-optic communication systems require transmitters that can encode optical signals with digital information. The two most widely used data formats are non-return-to-zero (NRZ) where the intensity does not go to zero between continuous 1 bits and return-to-zero (RZ) where the intensity returns to zero between continuous 1s as shown in FIG. 1. Optical transmitters using external high-speed modulators with low-chirp are essential for high-data-rate long-haul communication systems. Lithium niobate electro-optic intensity modulators have nearly zero output optical frequency modulation or chirp and are commonly used in commercial transmitters. However, they require large driving voltages at high bit rates (>2.5 Gb/s). Semiconductor electroabsorption modulators are key components for high-speed transmitters because they can be driven at low voltages (<3 Volts) even at high bit rates as described by Kataoka et al. in Electron. Lett., vol. 28, pp. 897-898 (1992). They can be constructed to be polarization insensitive, and are integrable with semiconductor lasers and amplifiers. However, they have two drawbacks: limited modulation speed caused by device capacitance and chirp.
There are two main types of electroabsorption modulators, namely, multiple-quantum-well and bulk waveguide devices. Both of these modulators operate under the principle that the optical absorption coefficient of the semiconductor increases in response to an applied electric field as described by Wood in J. Lightwave Technology, vol. 6, p. 743 (1988) and Keldysh in Soviet Phys. JETP, vol. 34, p. 788 (1958). This effect is intrinsically high-speed with response time in the sub-picosecond range. However, the modulation bandwidth of electroabsorption modulators is critically limited by device capacitance. The capacitance can be reduced somewhat by decreasing device area and/or increasing the waveguide layer thickness. But this comes at a significant trade-off of lower modulation on/off ratio, higher drive voltages, and more complicated and expensive device packaging.
Intensity modulators with low or negative chirp parameters are essential for long-haul transmission in conventional 1.3-.mu.m zero-dispersion optical fiber. The chirp parameter is a measure of the broadening of the spectrum of the modulated optical signal relative to the amount of its amplitude modulation as described by Devaux et al., in J. Lightwave Technology, vol. 11, p. 1937 (1993). The chirp parameter of electroabsorption modulator varies between -5 to 5 depending on many factors such as material structure, input wavelength, and applied voltage. This should be compared with the Mach-Zehnder type electro-optic intensity modulator with a chirp parameter approaching zero independent of applied voltage as described by Koyama et al. in "Frequency chirping in external modulators," J. Lightwave Technology, vol. 6, p. 87 (1988). Nonetheless, propagation in conventional fibers up to 300 km at 2.5 Gb/s using electroabsorption modulator-based transmitter has been demonstrated by Ishimura et al. in "Small chirp and wide bandwidth integrated modulator-laser at zero offset-bias operation," ECOC '97 Technical Digest, p. 171, 1997. At higher bit rates, the maximum propagation distance is limited because of the finite output chirp from the electroabsorption modulator. Chirp leads to severe signal distortion, inter-symbol interference, and even timing jitter after propagation through long distance of dispersive optical fiber. This results in unacceptable bit-error-rate at the receiver.
Electroabsorption modulators exhibit a highly nonlinear transfer characteristic versus voltage as described by Devaux et al. in "Optical processing with electroabsorption modulators," OFC '98 Technical Digest, p. 285, 1998. This nonlinear transfer characteristic is a result of the exponential nature of the absorption edge of the semiconductor. The nonlinearity can be exploited in applications such as all-optical wavelength conversion as described by Edagawa et al. in OFC '97 Technical Digest, p. 77, 1997, and generation of optical pulses as described by Devaux in "Light pulse generator," U.S. Pat. No. 5,559,628. The speed of the electroabsorption modulator for these applications depends on how well the modulator can respond to high-speed electric field modulation and is also limited by the device capacitance. Because of the finite size of the device, there is a lower limit of the capacitance and thus there exists an ultimate limit of the modulation bandwidth of electroabsorption modulators as described by Wood. Beyond this limit, optical signals from the modulator are severely distorted.

System comprising an electroabsorption modulator and an optical discriminator


An emergency vehicle shelter designed for women, senior citizens, and/or individuals with limited disabilities in mind; including an inflatable unit configured for nested engagement with a vehicle for covering the vehicle's upper and outer surfaces. The unit may be inflated by a remotely activated inflation unit. Provision is made in the unit member to allow a vehicle operator to reenter the vehicle for shelter from inclement weather.

1. Field of the Invention
The present invention is generally directed toward vehicle covers. In particular, the present invention is directed toward a vehicle cover which may be quickly installed with minimal effort for the protection of the exterior surface of the vehicle in the event of a hazardous weather situation.
2. Background Information
A variety of vehicle covers are available for protecting a vehicle's exterior surface from environmental hazards. Typically, the conventional vehicle cover consists of a single ply of material to protect a vehicle's surface finish from the everyday environment experienced in a storage situation, such as sun, wind, rain, dust, and bird droppings, among other things. However, clearly something more is needed for protection from the more damaging effects of a hail storm or other hazardous weather situation.
Even a conservative estimate would place annual repair costs to vehicles from hail damage in the billions of dollars. In an effort to provide a solution, inventors have long attempted to fill the need of a vehicle cover that provides protection to the outer surface of the vehicle from the damaging effects of hail. However, the solutions provided in the prior art fall short of the optimum balance between quick and efficient deployment and maximum protection as needed in the event of a sudden hail storm.
In effect the prior art reveals two categories of vehicle covers for protecting the surface of a vehicle from the effects of a hail storm. These may adequately be referred to as (1) the padded cover and (2) the inflatable cover. Prior art falling in the padded cover category includes that described in U.S. Pat. Nos. 4,699,192; 4,807,922; 5,664,825; 6,070,629; and 6,220,648. Although no inflation is needed for these prior art covers, the covers themselves require the use of thick, heavy materials. While this does provide some protection for the vehicle, it also typically provides a bulky, heavy, difficult-to-install cover that is not suitable for an emergency covering of the vehicle body, particularly by a single individual.
The second category, or inflatable type of covers, includes those covers described in U.S. Pat. Nos. 4,294,483; 5,242,206; 6,044,881; 4,966,406; and 6,439,644. These car covers all integrate some type of inflatable envelope; however, all of these covers also fall short of the optimum, because they do not provide for single-user emergency deployment. For instance, U.S. Pat. No. 4,294,483 issued to Ferris discloses an inflatable vehicle cover, but the vehicle cover in Ferris is clearly not intended, nor capable of, emergency use. That is, although a single user may be able to place the deflated cover in Ferris onto a car in an emergency situation such as a hail storm, the individual would also be required to locate bungee strips provided in Ferris and attach them to the cover for proper fit to the vehicle. Next, the individual would need to locate an external air compressor (as is the disclosed mechanism for inflation in Ferris), inflate the Ferris cover to the proper level, and shut the compressor off. Finally, the individual would need to seek shelter elsewhere, as Ferris (and the other prior art examples) fails to provide for reentry into the vehicle for temporary protection from the storm.
In view of the limitations associated with the prior art, a substantial need exists for an inflatable vehicle cover for use in emergency situations, which is light, fully covers the vehicle, and allows an individual to re-enter the vehicle for temporary shelter from the elements. Applicant's invention, through a novel combination of component pieces, provides such a mechanism.


A semiconductor device includes a plurality of gate trenches, each of which has first inner walls, which face each other in a first direction which is perpendicular to a second direction in which active regions extend, and second inner walls, which face each other in the second direction in which the active regions extends. An isolation layer contacts a gate insulating layer throughout the entire length of the first inner walls of the gate trenches including from entrance portions of the gate trenches to bottom portions of the gate trenches, and a plurality of channel regions are disposed adjacent to the gate insulating layers in the semiconductor substrate along the second inner walls and the bottom portions of the gate trenches.

1. Technical Field
The present disclosure relates to a semiconductor device and a method of manufacturing the same, and more particularly, to a semiconductor device with a trench gate type transistor and a method of manufacturing the same.
2. Discussion of Related Art
As the integration density of semiconductor devices, such as DRAMs, has increased, the size of memory cells has been scaled down. A reduction in the memory cell size requires a reduction in the size of cell transistors. Thus, many new methods have been developed to secure a predetermined cell capacitance in a memory cell having a reduced size cell transistor. Cell transistors are required to maintain excellent characteristics despite their reduction in size. Thus, various methods of controlling the concentration of impurity ions in diffusion layers have been proposed. However, as the channel length is reduced, it is difficult to control the depth of the diffusion layers during a semiconductor device manufacturing process that includes various thermal processes. Also, since the effective channel length is decreased and the threshold voltage is reduced, a short channel effect may occur, which seriously degrades the operation of the cell transistors.
A trench gate type transistor, in which a trench is formed in a surface of a substrate and a gate electrode is formed in the trench, has been developed. The trench gate type transistor can improve short channel effects in the transistor because the gate electrode is formed in the trench to extend a source-drain distance and increase the effective channel length.
In conventional methods of manufacturing a trench gate type transistor, an isolation region is formed that defines an active region in a semiconductor substrate, and then a trench is formed in the active region of the semiconductor substrate to form a gate electrode (for example, refer to U.S. Pat. Nos. 6,476,444 and 6,498,062).
However, if the trench, which is required for forming the gate electrode, is formed after the isolation region is formed as described above, an undesired short channel may be formed between the isolation region and the gate electrode when a distance between the isolation region and the gate electrode is short.
The formation of the undesired short channel will be described in more detail with reference to FIG. 1. FIG. 1 is a sectional view of a conventional semiconductor device. Referring to FIG. 1, an isolation region 12 is formed by a shallow trench isolation (STI) process in a semiconductor substrate 10. A sidewall 12a of the isolation region 12, which contacts an active region 14, is sloped due to a taper etch process. When a gate trench 16 is formed to form a gate electrode 20, a sidewall 16a of the gate trench 16 is also sloped due to a taper etch process. As a result, when a distance between the isolation region 12 and the gate electrode 20 is sufficiently small, as illustrated in FIG. 1, after a cell transistor is completed, a narrow silicon region 18 caused by the sloped sidewalls 12a and 16a may remain between the isolation region 12 and the gate electrode 20 in the semiconductor substrate 10. The silicon region 18 leads to an undesired channel between the isolation region 12 and the gate electrode 20. As a result, the cell transistor cannot ensure a sufficient threshold voltage.
A method of controlling an angle of inclination of a trench profile during an etch process for forming a gate trench or a method of using a wet etch process may be considered. However, these methods cannot completely remove a remaining silicon region between an isolation region and a gate electrode. Consequently, an undesired short channel may remain, thus adversely affecting the reliability of the resultant transistor.

Semiconductor device with trench gate type transistor and method of manufacturing the same


A sizing apparatus for determining the anterior-posterior size of a distal end of a femur. The apparatus includes a block having a face engageable with the distal end of the femur, and a body mounted on the block and slidable relative to the block in a medial-lateral direction. A stylus is mounted on the body.

Knee replacement surgery is currently performed with a view toward minimizing joint exposure by applying small incision procedures, also known as minimally invasive procedures. To obtain consistent results and aid the surgeon in such procedures, new instrumentation adapted to the smaller incision size is advantageous.
One of the important steps in knee replacement surgery is sizing correctly the femoral component and, in particular, accurately determining the anterior-posterior dimension of the resected distal femur. Several types of femoral sizers are currently available for this purpose. Nevertheless, femoral sizers that avoid soft tissue impingement and are well-suited to small-incision procedures are still desirable.


The present invention improves the geometry of ferrite circulators in order to increase the average power handling by decreasing the temperature rise in the ferrite and associated adhesive bonds. Embodiments of the present invention utilize dielectric attachments on the sides of the ferrite element, which maximizes the area of contact and minimizes the path length from the ferrite element out to the thermally conductive attachments.

1. Field of the Invention
The present invention relates to waveguide circulators, and more particularly to improved power handling capabilities for ferrite waveguide circulators through the use of thermally-conductive dielectric attachments.
2. Description of the Related Art
Ferrite circulators have a wide variety of uses in commercial and military, space and terrestrial, and low and high power applications. A waveguide circulator may be implemented in a variety of applications, including but not limited to transmit/receive (T/R) modules, isolators for high power sources, and switch matrices. One important application for such waveguide circulators is in space, especially in satellites where extreme reliability is essential and where size and weight considerations are very important. Ferrite circulators are desirable for these applications due to their high reliability, as there are no moving parts required. This is a significant advantage over mechanical switching devices.
A commonly used type of waveguide circulator has three waveguide arms arranged at 120° and meeting in a common junction. This common junction is loaded with a non-reciprocal material such as ferrite. When a magnetizing field is created in this ferrite element, a gyromagnetic effect is created that can be used for circulating the microwave signal from one waveguide arm to another. By reversing the direction of the magnetizing field, the direction of circulation between the waveguide arms is reversed. Thus, a switching circulator is functionally equivalent to a fixed-bias circulator but has a selectable direction of circulation. Radio frequency (RF) energy can be routed with low insertion loss from one waveguide arm to either of the two output arms. If one of the waveguide arms is terminated in a matched load, then the circulator acts as an isolator, with high loss in one direction of propagation and low loss in the other direction.
Generally, these three-port waveguide switching circulators are impedance matched to an air-filled waveguide interface. For the purposes of this description, the terms "air-filled," "empty," "vacuum-filled," or "unloaded" may be used interchangeably to describe a waveguide structure. Conventional three-port waveguide switching circulators typically have one or more stages of quarter-wave dielectric transformer structures for purposes of impedance matching the ferrite element to the waveguide interface. The dielectric transformers are typically used to match the lower impedance of the ferrite element to the higher impedance of the air-filled waveguide so as to produce low loss. Thin adhesive bondlines are used to attach the transformers to the ferrite element and the waveguide structure, so they also provide a thermally conductive path from the ferrite element to the waveguide structure for transferring heat out of the ferrite element.
Previous patents have described approaches for achieving broad bandwidth through the addition of impedance matching elements. Broadband circulators have high isolation and return loss and low insertion loss over a wide frequency band, which is desirable so that the circulator is not the limiting component in the frequency bandwidth of a system. Broad bandwidth also allows a single design to be reused in different applications, thereby providing a cost savings. These previous approaches for achieving broad bandwidth generally involve the addition of quarter-wave dielectric transformers or steps in the height or width of the waveguide structure to thus achieve impedance matching the ferrite element to the waveguide port. For example, previous approaches have disclosed achieving impedance matching by providing a step or transition in the waveguide pathway. This technique eliminates the standard dielectric transformers, thereby eliminating a thermal path for conducting heat out of the ferrite element. This technique also relies on the presence of a significant gap or spacing between adjacent ferrite elements, increasing the size and weight of the structure. These methods all require impedance matching elements in addition to the ferrite element in order to achieve acceptable performance. Other approaches include changing the shape of the ferrite resonant structure to achieve broadband performance. However, these ferrite structures are restricted to fixed-bias applications with a single direction of circulation.
Referring now to FIG. 1, there is shown a top view of a conventional ferrite element. Although magnetizing windings are not shown, dashed lines 135 denote the apertures for the magnetizing windings. The apertures 135 for the magnetizing windings may be created by boring a hole through each leg of the ferrite element, for example. If a magnetizing winding is inserted through the apertures, then a magnetizing field may be established in the ferrite element, as would be evident to those possessing an ordinary skill in the pertinent arts. The polarity of this field may be switched, alternately, by the application of current on the magnetizing winding to thereby create the switchable circulator.
Resonant section 130 exists where the legs of device 101 converge inside the three apertures 135. As would be evident to those possessing an ordinary skill in the pertinent arts, the dimensions of resonant section 130 determine the operating frequency for circulation in accordance with conventional design and theory. The sections 140 of the ferrite element in the area outside of the magnetizing winding apertures 135 may act as return paths for the bias fields in the resonant section 130 and as impedance transformers out of the resonant section. Faces 150 of the ferrite element are located at the outer edges of the three legs.
Referring now to FIG. 2, there is shown a top view of a conventional single-junction waveguide circulator structure. FIG. 2 shows a ferrite element 101 with a quarter-wave dielectric transformer 103 attached to each leg. As shown in FIG. 2, the quarter-wave dielectric transformers 103 are generally much narrower than the ferrite element 101, which limits the ability of the quarter-wave dielectric transformers 103 in providing a thermally conductive path from the ferrite element 101 to the waveguide structure 100. A dielectric spacer 102 may be disposed on the top and bottom surfaces of ferrite element 101. Spacer 102 may be used to properly position the ferrite element in the housing and to provide a thermal path out of ferrite element 101 to the conductive (electrically and thermally) waveguide structure 100. Conventional circulators have minimized the diameter of this spacer for impedance matching purposes, and the diameter is generally smaller than the size of resonant section 130 discussed hereinabove. Generally, a smaller diameter spacer will provide more frequency bandwidth and a poorer thermal path. This opposing effect makes high power, broadband circulators difficult to achieve.
The conventional components described above may be disposed within the conductive waveguide structure 100, which is generally air-filled. For the purposes of this description, the terms "air-filled," "empty," "vacuum-filled," or "unloaded" may be used interchangeably to describe a waveguide structure. Conductive waveguide structure 100 may include waveguide input/output ports 105. Ports 105 may provide interfaces, such as for signal input and output, for example. Empirical matching elements 104 may be disposed on the surface of conductive waveguide structure 100 to affect the performance. Matching elements 104 may be capacitive/inductive dielectric or metallic buttons that are used to empirically improve the impedance match over the desired operating frequency band.
Referring now to FIG. 3, there is shown a partial side view of a conventional single-junction waveguide circulator structure. As may be seen in FIG. 3, only one of the three legs of the ferrite element is shown. This view shows dielectric spacers 102 located between the walls of waveguide structure 100 and ferrite element 101. Adhesive materials are used to bond the dielectric spacers 102 to the waveguide structure 100 and to the ferrite element 101. As a result of the dielectric spacers 102 being much smaller in diameter than the legs of ferrite element 101, air gaps 110 exist above and below portions of the legs of the ferrite element. Air gaps 110 may be approximately one-third the height of the waveguide in the E-plane axis. Co-pending, commonly assigned patent application, U.S. non-provisional patent application Ser. No. 11/107,351 titled Latching Ferrite Waveguide Circulator Without E-Plane Air Gaps (the '351 application), incorporated herein by reference, describes implementations wherein the E-plane air gaps have been eliminated through the use of filler materials between the ferrite element 101 and the waveguide structure 100. The primary purpose of these filler materials is to suppress the high peak power breakdown effects such as arcing or multipactor. For broad bandwidth applications, these materials will generally have a low dielectric constant (less than 3), thereby preventing the use of the more thermally conductive dielectrics such as aluminum nitride, boron nitride, and beryllium oxide, which all have relative dielectric constants greater than 4.
The purpose of a ferrite circulator is to circulate RF power from one port to another while absorbing a minimal amount of the circulating power. All of the dielectric and ferrite materials in circulators absorb some power, but the majority of the power absorbed by a ferrite circulator is contained in the ferrite element due to the relatively high volume of the ferrite element 101 and the high electrical and magnetic loss tangents of the ferrite material. In conventional single-junction waveguide circulators, such as illustrated in FIG. 3, the ferrite temperature rise resulting from the power absorption is primarily dependent on the thermal resistance of the various paths from the ferrite element 101 to the thermally conductive waveguide structure 100. The waveguide structure 100 acts as a heat sink for the ferrite element 101, but the thermal paths between these two parts are limited in conventional circulators. These paths flow from the ferrite element 101 through adhesive bonds to either the dielectric spacers 102 or quarter-wave dielectric transformers 103 and on through adhesive bonds to the waveguide structure 100. The dimensions of the dielectric spacers 102 and quarter-wave dielectric transformers 103 are restricted by RF performance requirements rather than thermal requirements.
Accordingly, a need exits for a ferrite circulator that incorporates thermally conductive dielectric attachments in order to maximize the area of contact with the ferrite for improved heat transfer beyond the present art, thereby allowing ferrite circulators to operate at higher average microwave power levels.

Ferrite waveguide circulator with thermally-conductive dielectric attachments


The invention is directed to a method, system, and computer program product for the synchronization of similar data objects by exchanging event information to provide new and/or updated data objects to a mobile device or application for use on a device. The invention includes a method, system, computer program product, and combinations and sub-combinations thereof, for enabling similar data objects to be made available to users of mobile devices, and for the users of mobile devices to operate with such objects on their mobile devices in an interactive manner while in an off-line mode, i.e., while not actively connected to a network or external data source.

1. Field of the Invention
The present invention relates generally to mobile communications, and more particularly relates to technology for synchronizing data with mobile devices.
2. Related Art
Over the past few years, there has been a large growth in the number of hand-held computers, personal digital assistants (PDA), and other mobile devices. In addition, there has been a marked increase in the number of ways for mobile devices to connect to the global Internet and the World-Wide Web (WWW), corporate internets, intranets, and other networks. This collective expansion allows users of mobile devices to access various types of information, disseminate information, and be exposed to electronic commerce (e-commerce) activities, all with a greater degree of freedom. E-commerce includes entities such as large corporations, small businesses, individual entrepreneurs, organizations, and the like who offer their information, products, and/or services to people all over the world via these networks.
The rise in use of mobile devices, however, also presents users, particularly users of more than one device, computer, or part of a company or group which uses such devices, with the problem of keeping their information contemporary and continuous. Various synchronization techniques have been developed to convey information from a computer or server to a mobile device and from the mobile device to the computer or server. However, these techniques do not provide the dynamic mobility required by users of one or more mobile devices connected to one or more networks.
Increasingly, the users of mobile devices have more than one mobile device, such as a cellular telephone and a personal digital assistant (PDA) the sharing of information among which benefits the user. In addition, corporations can have employees with more than one mobile device each, all of which require consistent information in order for the corporation to operate effectively.
Therefore, in view of the above, what is needed is a system, method and computer program product for the synchronization of similar data objects to one or more devices by exchanging event information. Similar data objects can include information requested or required by users of mobile devices. Event information can be constructed and exchanged by the system of the present invention. Further, what is needed is a system, method and computer program product that delivers event information to mobile devices based on information provided by one or more users.

Method, system, and computer program product for synchronization of similar data objects with event information


There is provided a polarizing plate with a retardation layer that can achieve an image display apparatus having excellent durability and excellent weatherability, and having an excellent hue. A polarizing plate with a retardation layer according to an embodiment of the present invention includes in this order: a polarizing plate including a protective layer and a polarizer; a retardation layer; and a pressure-sensitive adhesive layer. The protective layer has a light transmittance at a wavelength of 380 nm of 10% or less. The polarizing plate has a light transmittance at a wavelength of 380 nm of 5% or less. The pressure-sensitive adhesive layer has a light transmittance at a wavelength of 405 nm of 5% or less. The polarizing plate with a retardation layer has a light transmittance at a wavelength of 405 nm of 3% or less.

In recent years, image display apparatus typified by a liquid crystal display apparatus and an organic EL display apparatus have been rapidly gaining more widespread use. In the image display apparatus, a polarizing plate and a retardation plate are typically used. In practical use, a polarizing plate with a retardation layer, in which the polarizing plate and the retardation plate are integrated, is widely used (for example, Patent Literature 1). In this connection, recently, along with an increasing demand for thinning of the image display apparatus, there has also been an increasing demand for thinning of the polarizing plate with a retardation layer.
Incidentally, the image display apparatus (especially the organic EL display apparatus) involves a problem in that its characteristics deteriorate with time owing to UV light (its weatherability is insufficient). A technology involving imparting a UV-absorbing ability to an optical film to be used in the image display apparatus has been investigated for improving the durability of the image display apparatus. However, the technology involves a problem in that the hue of the apparatus changes, and hence desired display characteristics are not obtained.

Polarizing plate with retardation layer and image display device