Apparatus and methods provide individual blades driven by drives configured to reduce a tendency of sludge to be moved in an undesired return direction. Drive configurations apply “pull” and “pull” forces that only pull on tensile structures, avoiding a need in actual commercial practice for use of extra structural drive members having high resistance to both tension and compressive forces exerted parallel to a sludge movement direction. Each of two separate tensile structures carries one blade, or a separate set of blades, with blade(s) of one structure adjacent to, and alternating with, blade(s) of the other structure. Embodiments move sludge from a corner of a basin and across a floor of the basin. The reduced tendency of sludge movement in the return direction results from moving one tensile structure and blade(s) in the sludge movement direction as the other tensile structure and adjacent opposed blade(s) move in the return direction.

1. Field
The present invention relates generally to removing materials from liquids, and more particularly to adjacent opposed, oppositely moving blades for, and methods of, moving sludge in a sludge collection basin for removal of the sludge from the basin.
2. Description of the Related Art
In the past, containers (e.g., basins or tanks) have been provided to house apparatus in which materials are collected. The materials may have any of a wide variety of compositions, and generally consist of pieces of the materials that move under the force of gravity to the bottom (or floor) of the basin ("settleable-particles"). For example, in municipal waste water systems, the materials may be formerly biologically-active waste materials that are no longer biologically-active, and that are in the form of the settleable-particles.
For ease of description, materials within the wide range of compositions and that consist of the settleable-particles, are referred to as "particles", and in the context of particles that have settled, or moved, to the bottom of the basin, such materials are referred to as "sludge".
The settleable-particles may be collected from liquids by plate or tube settlers that promote settling of the settleable-particles to the bottom of the basin. In other cases, flocculators may be housed in such containers. Settleable-particles often inadvertently move in the flocculators to the bottom of the basin. Because the flocculators are designed to circulate liquid and materials, rather than to promote settling of the materials, the materials that inadvertently collect at the bottom of the basin present a problem.
In the case of the settlers, for example, the sludge must be removed from the bottom to make room for more sludge collected from more liquid and materials that flow into the basin. In the past, sludge removal equipment has been mounted on or near the bottom for moving the sludge along the bottom to sludge outlets that allow removal of the sludge from the basin. The moving has been done by scrapers that are mounted together for traverse together from one end of the basin to an opposite end of the basin. On each traverse in one direction, each of the scrapers pushes sludge in the same direction to the outlet at one end. On each reverse traverse in the opposite direction, each of the scrapers pushes sludge to the outlet at the other end. In this scraper system, the scrapers must be able to push the sludge in each of the directions, and move together in the respective direction to perform the pushing.
Others have attempted to use scrapers of a different design, in which the scrapers need only be able to push the sludge in one direction across the bottom while moving together in the one direction to perform the pushing. In the use of these different scrapers, such as those described in U.S. Pat. No. 5,431,818 to K. D. Zickert issued Jul. 11, 1995, the distance through which each of the scrapers is moved has been greatly reduced, e.g., to about two feet. Problems are described in that patent in the use of a wedge-shaped scraper having a generally right-triangular cross-section, such as the scrapers 30 shown in FIGS. 1A and 1B. Many such scrapers 30 are attached to one net 32. The one net 32 is moved in a "to" (forward, sludge-moving direction, arrow 34) and in a "fro" (return, or reverse direction, arrow 36) reversing traverse. In this manner, the one net 32 moves all of the scrapers 30 together in one time period (TP) through the two foot distance in one direction (e.g., the forward, "to", direction 34, FIG. 1A). The one net 32 then reverses, and moves all of the scrapers 30 together in a next TP through the same two foot distance in the opposite direction (arrows 36, FIG. 1B).
In an effort to increase the efficiency of sludge movement in the forward direction 34, in U.S. Pat. No. 5,431,818 the cross-section of the scrapers 30 was modified, and all of the modified scrapers 40 (FIGS. 1C and 1D) were moved together in the same "to" direction 34 and together in the "fro" direction 36 at controlled speeds in the same time periods. Unfortunately, that cross-section of the modified scrapers 40 was made more complex by the selection of a curved configuration 41 shown in FIGS. 1C and 1D. That configuration 41 was described as a downwardly facing bottom surface 42, a substantially oblique, convex surface 44, and a substantially vertical, concave surface 46 facing in the forward direction (arrow 34). The complex, modified scraper 40 was said to minimize turbulence.
However, Applicant's analysis of the complex modified scraper 40 indicates that those advantages may be offset (i.e., substantially reduced) by many factors. One such factor is the movement of all of the scrapers 40 together (i.e., in the same direction at the same time). Applicant's analysis indicates that there is a tendency, for example, for undesired movement of the sludge in the return direction 36 due to all of the scrapers 40 moving together (at the same time in the return direction 36), which tendency is also promoted by the one net 32 attached to and moving with all of the blades. The undesired movement in the return direction reduces the efficiency of the desired movement in the "to" (or forward) direction.
Also, although the one net 32 is described in U.S. Pat. No. 5,431,818 as being pulled in the forward direction 34, and as being pulled in the return direction 36 (as by a spring), there are commercial embodiments that appear similar to the above-described system that uses the complex modified scrapers 40. Those commercial embodiments have the one net 32 reinforced and driven by a structural drive member (not shown) that has high resistance to both tension and compressive forces exerted parallel to the directions 34 and 36. Thus, in commercial practice, an extra structural member has been used to apply respective "to" and "fro" forces to the one net 42 to cause the to and fro motion. Such an extra structural member has increased the cost and weight of those commercial embodiments, and the extra weight increases the required energy (e.g., electrical power and thus operating cost) to move the scrapers.
Applicant's analysis further indicates another disadvantage of the substantially oblique, convex surface 44 (or the right-triangular cross-section of the blades 30), in combination with all of the modified scrapers 40 (or all of the scrapers 30) moved together in the same "to" direction 34 and together in the "fro" direction 36 in the same time periods. As noted, this structure and movement results in undesired movement of the sludge in the return direction 36 due to all of the scrapers moving together (at the same time in the return direction 36). In an apparent attempt to reduce the undesired movement of the sludge in the return direction 36, the U.S. Pat. No. 5,431,818 teaches use of a higher speed for the return stroke than for the forward stroke (e.g., 12 m/minute return vs., 3 m/minute forward). Such a higher speed return stroke can agitate the particles of the sludge causing some of the particles to be reintroduced into the liquid that was clarified by the settler, for example. This further reduces the efficiency of the overall operations because the reintroduced particles have to be again settled and then removed from the basin.
Applicant's analysis further indicates yet another disadvantage of all of the scrapers 30 or 40 moving together in the same "to" direction 34 and together in the same "fro" direction 36 in the same time respective periods. All of the prior push surfaces (e.g., 46) engage and push the sludge at the same time and are thus resisted by the sludge at the same time. The requirement for higher power for this pushing of all blades together at the same time, and the increased weight of the extra compressive member that enables pushing instead of pulling the structure, result in the motor used for moving the system being more costly than a lower-power motor. Also, such extra compressive member makes the net 32 less compliant with respect to uneven floors of the basin, which in turn results in higher costs to initially provide a smoother floor for the basin (e.g., of concrete) and higher repair costs in not damaging the smoother floor of the basin during repair.
Lastly, if a generally-triangular cross-section blade is to be used, there is additional cost to manufacture the convex and concave shapes of the scrapers 40.
Accordingly, there is a need for a sludge system and methods that reduce the tendency of the sludge to be moved in the return direction 36 (such tendency being caused by all of the scrapers moving together in the same return direction during a given time period). Further, there is a need for such system and methods to avoid the need, in actual commercial practice, for the use of any structural drive member other than the one net (or a main frame) that supports (or carries) the blades themselves. Thus, there is a need in actual commercial embodiments to eliminate the above-described extra structural drive member that has high resistance to both tension and compressive forces exerted parallel to the directions 34 and 36. Also, there is a need in actual commercial embodiments for the individual scrapers, or blades, to have a configuration manufacturable in a low-cost manner.

Methods of and sludge collector with adjacent opposed oppositely-moving blades for moving sludge in a basin


Communications signals are transmitted over a power distribution network. A plurality of communications stations which are coupled to the power lines are served by a base station. Communications signals are coupled between the base station and the distribution network, and the flow of the communications signals is controlled according to the station that it is desired to communicate with by preferentially transmitting along or receiving from a power line to which the desired communications station is coupled. The base station can be coupled to each of the power lines or to the busbars at a distribution station.

It has been proposed to transport telecommunications signals over a power line. International Patent Application WO 98/06188 A1 (Northern Telecom) describes such a network. Delivering a telecommunications service in this manner is attractive as it overcomes the need for installing cabling to each subscriber, which is one of the greatest costs in providing a new telecommunications network. Existing power lines are used to carry the telecommunications signals to subscribers.
Power line transmission is one of several ways for delivering communications to subscriber premises and is therefore sensitive to competition with existing copper wires and more recent alternatives such as optical fibre/coaxial cable delivery and fixed radio access techniques. Therefore, there is a desire to provide a system that is capable of delivering an acceptable quality of service at a cost that is attractive to a subscriber.
In the above-mentioned WO 98/06188 A1 communications signals are injected onto one or more of the power lines leading from an electricity substation at a position on the line near to the substation.

Transmitting communications signals over a power line network


A device for electrical isolation is suitable for installation in the core hole of a toroidal core. The device includes a center section that has a rotational axis, and branches that extend outwards and that are deformable in the rotational direction about the rotational axis. Each branch has an insulating region that preferably extends in the radial direction and that is thicker than the branches.

An insulating part suitable for electrical isolation (or potential isolation) is known, for example, from the publication of German patent application DE 10223995 C1. The insulating part includes the toroidal core of a toroidal core choke and has projections for fixing wire windings and also for maintaining a grid dimension. The insulating part has branches, which provide the potential isolation, in the center region.
Another insulating part suitable for potential isolation is known, for example, from German patent application publication DE 10308010 A1. The insulating part has branches that extend outward in the radial direction and can be deformed elastically in the radial direction by pressure.

Device for electrical isolation, toroidal core choke, and method for producing the toroidal core choke


A method of conducting smooth motor startup is provided and includes operating a motor in an open loop control scheme at startup, operating the motor in a closed loop sensorless control scheme at a time after startup and transitioning between the open loop control scheme and the closed loop control scheme by reducing a difference between an estimated rotor angle of the motor and a commanded ramping angle of the motor.

Variable speed technology using permanent magnet synchronous motors (PMSMs) for compressors is one of the emerging technologies to lead efficiency improvements in today's Heating, Ventilating and Air Conditioning (HVAC) systems. Different from induction motors, PMSMs need to know rotor position to be able to control the rotor. Since the motor is normally disposed inside the compressor without any speed sensor, rotor angle and speed estimation is needed to control the PMSM compressors. Most rotor angle and speed estimation techniques operate at relatively low efficiencies at low speeds due to noise and low currents, however, and the general approach in these cases is therefore to start the compressor in an open loop control scheme and then switch to a sensorless vector control scheme.
With this approach, the switch transition may at times cause high spike currents, oscillations and stability issues that tend to reduce the product's lifetime and may increase failure rates. Also, the PMSM compressor has to release its pressure difference, which means the compressor may not be able to immediately restart leading to energy stored in the compressor potentially being lost.


A power module is configured to accept power from a cable, wherein the power module may be inserted into a standard wall cavity via a small hole. A processor module coupled to the power module comprises a processor and is configured to accept power from the cable for the processor, wherein the processor module may be inserted into the standard wall cavity via the small hole. A sensor module coupled to the processor module, comprises a sensor and is configured to accept input from the sensor for the processor, wherein the sensor module may be inserted into the small hole.

One use for technology is to establish a system of control. In premises automation, for example home automation, a system controls various aspects of the premises such as lighting, music, and heating, ventilation and air conditioning (HVAC) based in part on user input. Premises are architected to be livable spaces for humans, which include architectural and aesthetic design to appeal and be compatible with humans. Without an architecturally acceptable system, some designers may only rely on manual or simplistic control of the premises, which may be overwhelming, confusing, and/or time consuming for a manual operator. Thus, it would be an improvement to have architecturally compatible ways to provide premises automation.

Small architectural distributed premises automation


An improvement is proposed in the so-called urea method for the preparation of fine particles of yttrium oxide, according to which, while an aqueous reaction mixture containing a water-soluble yttrium salt, e.g., nitrate, and urea dissolved therein in specified concentrations is heated at 90.degree. to 100.degree. C. to effect precipitation of yttrium carbonate hydroxide particles followed by calcination of the carbonate hydroxide in air into yttrium oxide, the aqueous reaction mixture is diluted with addition of a specified volume of preheated water within a critical period between incipient appearance of turbidity in the reaction mixture by the precipitation of the carbonate hydroxide and a moment 30 minutes thereafter. In this way, the yttrium oxide particles obtained have a globular particle configuration with a very small average particle diameter D.sub.50 in the range from 0.1 to 0.3 .mu.m and are suitable for use in various fine applications.

The present invention relates to a method for the preparation of fine globular particles of yttrium oxide or, more particularly, to a method for the preparation of fine particles of yttrium oxide having a globular or spherical particle configuration and having usefulness as a base material of a sintered body of yttrium oxide, sintering aid of various kinds of ceramic materials, base material of luminescent phosphors, coating agent on the particles of a luminescent phosphor and so on by virtue of absence of agglomeration and good dispersibility of particles.
While yttrium oxide powders are used widely in the above mentioned applications, it is desirable that the particles of the yttrium oxide powder therefor are as fine as possible to have a particle diameter in a submicron range and also the particles have dispersibility as high as possible. Such fine particles of yttrium oxide can be prepared in two different ways in the prior art. The first of the known methods therefor is to mechanically comminute separately prepared particles of yttrium oxide having a coarse particle diameter exceeding the desired submicron order by the use of a suitable pulverizing machine such as beads mills, optionally, with addition of a dispersing aid. This mechanical method, however, is industrially not feasible due to several problems and disadvantages. For example, it is by no means possible to avoid contamination of the yttrium oxide particles by the materials of the pulverizing machine and the beads as the pulverization medium as well as by the dispersing aid, when used. In addition, the efficiency of conventional pulverizing machines is generally not high enough when the desired particle size of the powder concerned is so fine as in the submicron range so that the productivity of the method is low as an industrial process.
As a natural consequence of the particle size reduction by a mechanical means, moreover, the particles obtained by this mechanical pulverization method usually have an irregular particle configuration with rugged surfaces as is evidenced by the discrepancy between the specific surface area obtained by the so-called BET method utilizing adsorption of nitrogen molecules and the imaginary specific surface area estimated by calculation from the value of the average particle diameter D.sub.50 of the particles assuming a perfectly spherical particle configuration and monodispersed distribution of the particle diameters, the former value usually being much greater than the latter. This discrepancy is presumably due to the fact that the specific surface area obtained by the BET method involves the additional areas due to the surface ruggedness of the particles as well as the internal surface areas provided by the cracks, fissures and pores occurring inside of the particles. In this regard, one of the evaluation items of a yttrium oxide powder is the discrepancy between or ratio of the specific surface area obtained by the BET method and the imaginary specific surface area calculated from the average particle diameter of the particles as mentioned above.
The second of the known methods for obtaining submicron particles of yttrium oxide, referred to as the urea method hereinafter, is a chemical method in which an aqueous solution of a water-soluble inorganic salt of yttrium is admixed with urea and the thus prepared reaction mixture is heated so that the urea in the solution is hydrolyzed into ammonium and carbonate ions which cause precipitation of fine particles of yttrium carbonate hydroxide having a submicron particle diameter followed by recovery of the precipitates and calcination thereof in an oxidizing atmosphere to convert the same into particles of yttrium oxide. A problem in this urea method is that, when yttrium oxide particles having an average particle diameter not exceeding 0.2 .mu.m are desired as the product, the concentration of the yttrium salt in the aqueous reaction mixture must be kept so low as not to exceed 0.01 mole/liter relative to yttrium. Accordingly, the urea method is undertaken only in a laboratory scale and is practically not industrial due to the low productivity.

Method for the preparation of fine globular particles of yttrium oxide


Exemplary embodiments are directed to an amplifier module which may comprise a transmit path including a first amplifier and a second amplifier. The exemplary amplifier module may further include a transformer coupled between the first amplifier and the second amplifier and switchably configured for coupling the first amplifier in series with the second amplifier in a first mode and coupling the first amplifier to bypass the second amplifier in a second mode.

1. Field
The present invention relates generally to power amplifiers. More specifically, the present invention relates to methods, systems, and devices for multi-mode, multi-band power amplifiers.
2. Background
In a wireless communication system, a transmitter may process (e.g., encode and modulate) data to generate output samples. The transmitter may further condition (e.g., convert to analog, filter, frequency up-convert, and amplify) the output samples to generate an output radio frequency (RF) signal. The transmitter may then transmit the output RF signal via a wireless channel to a receiver. The receiver may receive the transmitted RF signal and perform the complementary processing on the received RF signal. The receiver may condition (e.g., amplify, frequency down-convert, filter, and digitize) the received RF signal to obtain input samples. The receiver may further process (e.g., demodulate and decode) the input samples to recover the transmitted data.
The transmitter may support multiple modes and multiple frequency bands. Each mode may correspond to a different radio technology, and each frequency band may cover a different range of frequencies. The transmitter may include a number of power amplifiers to support the multiple modes and the multiple bands. For example, each power amplifier may support a specific mode on a specific band. A relatively large number of power amplifiers may then be required for the transmitter, which may increase size and cost of the transmitter.
A need exists for an enhanced multi-mode, multi-band power amplifier. More specifically, a need exists for increasing power added efficiency and decreasing insertion loss of a multi-mode, multi-band power amplifier.


A method for managing focus in a graphical user interface using a directional controller that allows a directional or selection input. The method comprising: determining whether the input is directional or selection; determining whether there is a sibling object of a currently focused object in a given direction of the input if the input is directional; transferring the focus to the sibling object if there is a sibling object in the given direction; transferring the focus to an ancestor object of the currently focused object if there is no sibling object in the given direction; determining whether the currently focused object is a group; transferring the focus to a descendant object of the currently focused object if the currently focused object is a group and the input is selection; and selecting the currently focused object if the currently focused object is not a group and the input is selection.

In a typical window-based graphical user interface (GUI), a group of visually distinct display objects are provided on the display screen. The GUI objects include objects that are visual images such as text and/or a picture. More specifically, the GUI objects include a button, a list box, a check box, a menu bar, and other related objects such as an "icon". The GUI objects provide certain information to the user and allow selection by the user.
A focus displayed on a GUI display screen allows the user to point at a given GUI object on the screen using input units such as a keyboard, a remote controller of a television, a controller of a game console, or a keypad for a PDA. The focus is a visual indication showing an area on a GUI screen currently referenced by the user and is represented, for example, by a shaded box enclosing the currently referenced GUI object. Such a focus is necessary when the user uses an input unit such as a keyboard, a group of directional buttons, or a keypad, unlike a pointing device such as a mouse, and cannot directly point at a given area on the GUI display screen.
A GUI screen control system controls the focus so that the focus moves from one area to another on the GUI screen in response to operations of a button or a key indicating a direction such as up, down, right, or left on a controller or a keypad. When the user presses a button or a key indicating confirmation, the GUI screen control system recognizes a focused GUI object as having been selected by the user and controls the processing according to the properties of the selected GUI object.
However, the need exists for a technique to design an efficient focus management system for a GUI screen that is controlled by input units such as a keyboard, a controller, or a keypad.


In one embodiment, a probe adapter includes: a holder configured to be detachably attached to an ultrasonic probe; a marker configured to be disposed at a predetermined position in an array direction of the ultrasonic probe and mark a surface of an object which the ultrasonic probe is brought into contact with, under a state where the holder is attached to the ultrasonic probe; and a wiper configured to remove an ultrasonic medium coated on the surface of an object.

An ultrasonic diagnostic apparatus is configured to non-invasively acquire information inside an object by transmitting an ultrasonic pulse and/or an ultrasonic continuous wave to an object's body and converting the reflected ultrasonic wave into an electric signal with the use of transducers. Note that the reflected ultrasonic wave is generated due to difference in acoustic impedance between respective tissues in the object. In an ultrasonic diagnostic apparatus, transducers are included in an ultrasonic probe, and are controlled such that the transducers transmit an ultrasonic pulse and/or an ultrasonic continuous wave and receive the reflected ultrasonic wave(s).
In a medical examination with the use of an ultrasonic diagnostic apparatus, various type of moving image data and real-time image data can be easily acquired by scanning an object with the ultrasonic probe, i.e., bringing the ultrasonic probe into contact with the surface of the object. Thus, an ultrasonic diagnostic apparatus is widely used for diagnosis of shape and property of an abnormal part such as a tumor and for imaging blood-flow dynamics.
For instance, in a biopsy examination, a living tissue including an abnormal tissue such as a tumor is extracted by using a puncture needle punctured into inside of an object while the inside of the object is being imaged with an ultrasonic diagnostic apparatus on a real-time basis, and the cells included in the extracted living tissue are examined. In a biopsy examination, a puncture position is carefully determined in such a manner that a puncture needle is infallibly punctured into a living tissue including a tumor. Thus, when a biopsy examination is performed, in some cases, a puncture position is determined in advance while a position of a tumor is being observed with an ultrasonic diagnostic apparatus, and then marking is performed on a skin surface of an object with, e.g., a medical marker.
When a tumor is surgically removed aside from a biopsy examination, a tumor position is sometimes marked on a skin surface of an object by preoperative imaging with the use of an ultrasonic diagnostic apparatus. Additionally, in an operation called percutaneous transluminal angioplasty, a running state of blood vessels are sometimes confirmed by imaging with the use of an ultrasonic diagnostic apparatus prior to the operation so that marking indicative of the running state of blood vessels is performed on the skin surface of the object.
Further, as compared with other modalities such as a magnetic resonance imaging apparatus, it is difficult to reproduce imaging of the same region of the same object without marking in the case of an ultrasonic diagnostic apparatus. In imaging with the use of an ultrasonic diagnostic apparatus, it is possible to image the same region again with satisfactory reproducibility by marking a moving trace of an ultrasonic probe on a skin surface of an object. When it is required to display the abnormal part identified in the examination again at the time of the operation, the region to be imaged can be easily reproduced by the marking performed in the examination.
In the above-described case, a user such as a doctor performs marking on a skin surface of an object while imaging inside of the object with manipulating the ultrasonic probe. In this case, when a user performs marking on a target, i.e., a skin surface of an object with a medical marker, the user holds the ultrasonic probe with one hand and holds the medical marker with the other hand so as to perform different manipulations with both hands. When the user performs marking with the non-dominant hand, operability of the ultrasonic probe, marking efficiency, and marking accuracy are reduced.

Probe adapter, ultrasonic probe, and ultrasonic diagnostic apparatus


A Poisson-quantization noise model for modeling noise in low-light conditions is described. In one aspect, image information is received. A Poisson-quantization noise model is then generated from a Poisson noise model and a quantization noise model. Poisson-quantization noise is then estimated in the image information using the Poisson-quantization noise model.

Noise is inevitable in any imaging device. This is especially the case in low-light situations (also known as photon limited situations) arising from either a weak light source illuminating an object being photographed, or the use of a small or low quality lens by the device attempting to photograph the object. In either case, the low light situation often precludes the capture and rendering of a high quality image.

Determining intensity similarity in low-light conditions using the Poisson-quantization noise model


According to some embodiments, a tactile information estimation apparatus may include one or more memories and one or more processors. The one or more processors are configured to input at least first visual information of an object acquired by a visual sensor to a model. The model is generated based on visual information and tactile information linked to the visual information. The one or more processors are configured to extract, based on the model, a feature amount relating to tactile information of the object.

Recently, research regarding machine learning dealing with a plurality of pieces of information such as visual information, audio information, and operation information is widely conducted. Research regarding performance of control of an object by using information such as detection of force input from a tactile sensor is also widely conducted.
However, results of such research indicate that it is difficult to obtain tactile information from obtained visual information, which is an operation experientially performed by a human being such that, for example, a portion of an object which is unlikely to be slippery is determined from visual information. For this reason, it is a difficult task to make a robot perform an operation such as seeing an object, judging a portion of the object which is unlikely to be slippery, and grasping the object based on the judgment result, in a manner that a human being performs normally.

Tactile information estimation apparatus, tactile information estimation method, and program


A collision avoidance device for an aircraft of the type comprises means for the geographical localization of the aircraft, means for the computation, for each geographical place, of a safety floor above which the aircraft must be positioned, means to predict the position in the air of the aircraft between a first given instant and a second given instant and means to compare the predicted position in the air of the aircraft with respect to the specified security floor. The safety floor, which is used for the comparison, is consolidated beforehand by means of a sensor that detects the obstacles in a forward sector of the aircraft and provides means with measurements enabling the computation of the altitude of these obstacles with respect to a reference level. The disclosed device has the advantage of enabling a reduction in the risk of delayed alarms and harmful alarms.

1. Field of the Invention
The present invention relates to a collision avoidance device, especially a device for avoiding collisions with the ground. It can be applied in particular to civilian airliners. More generally, it can be applied to all aircraft that, in the course of their mission, have to come excessively close to the ground, for example when they are near mountains, or that have to maneuver in sectors of air space where they constitute a danger or are themselves in danger, for example in areas to which access is prohibited.
2. Description of the Prior Art
Devices for avoiding collision between aircraft and the ground are known. These devices are characterized chiefly by the use of radio-altimeters, computers that give the barometric height on the basis of pressure and temperature measurements and navigation means such as an inertial guidance system or a flight management system. The principle of these devices lies in making use of an altimeter height, taken with respect to the ground, and in making use of variations in radio-altimeter height or barometric height. The latter is used in particular because, as compared with altimeter height variations, it is available for great heights. These distances from the ground are compared with threshold values that themselves depend on the values of heights and the configuration of the aircraft, depending on whether its undercarriage, flaps or slats are deployed for example. When the parameters measured, the heights and the variations of heights as a function of time in particular, exceed the threshold values, an alarm is sent to the crew. However, such devices have the drawback of giving measurements that are excessively delayed with respect to the maneuvering of the aircraft, and hence of generating alarms that are often excessively delayed and prevent the crews from reacting in time. It is therefore likely that such devices will not to prevent collision. This may happen in particular when the relief takes a sudden upward turn, for example when the aircraft moves towards the side of a sharply rising mountain. Another drawback of the known devices is that they generate unwarranted alarms which are also called false alarms. These may occur for example when the aircraft are flying over low-altitude mountains with a good safety height but when rising features of the relief for example, while being harmless, cause false alarms. These drawbacks seriously reduce the credibility of these anti-collision devices.
Improvements have been made to these devices, for example by introducing databases that enable the modulation of the value of the thresholds to be taken into account as a function of the geographical position of the aircraft. These improvements are likely to reduce the false alarms. However, they require databases adapted to each type of terrain. As an extension of this latter approach, it is possible to envisage the preparation of a digital field model that would provide permanent knowledge, depending on the position of the aircraft, of the nature of the relief ahead of this aircraft. Nevertheless, the use of such a model would require a database describing the relief in a sufficiently precise way, hence a database that requires large-sized memories. In addition to this drawback, there is the need for procedures of exchange and for updating a database of this type. This complicates its use. The large number of information elements stored furthermore entails non-negligible risks of error. The performance characteristics of these devices, especially in terms of harmful alarms, is related essentially to the resolution of the database. Indeed, the uncertainty of measurement as regards the position of the aircraft must be taken into account in the computation of the alarm in order to prevent any belated alarm. This leads to a possibility of harmful alarms.
The present Applicant, in the document FR 2.697.796, has already proposed a collision-avoidance device for an aircraft that mitigates the above-mentioned drawbacks, especially by getting rid of random factors of variation in relief and by determining the position of the aircraft no longer with respect to the ground but with respect to known safety altitudes.
This document describes a collision avoidance device for an aircraft comprising means of geographical localization, means for the computation, on the basis especially of each geographical location and of safety altitudes memorized in a database, of a safety floor above which the aircraft should be located, means for predicting the air position of the aircraft between a first given instant and a second given instant and means to compare the predicted air position of the aircraft with respect to the constructed floor.
During operation, an alarm is, for example, activated as soon as the result of the comparison indicates that a predicted air position of the aircraft is below the floor.
The present invention is an improvement on the above device, enabling an increase in the resolution of the information elements used in the computation of alarms, without however increasing the volume of the database. It also makes it possible to be no longer dependent on possible errors in the measurement of navigation and thus makes it possible to cancel the risk of a belated alarm.

Collision avoidance device for aircraft, especially for avoiding collisions with the ground


Disclosed herein is a multi-directional toothbrush for protecting teeth. The multi-directional toothbrush includes a rotatable toothbrush part, a rotatable toothbrush part support frame, and a vertically moving toothbrush part. The rotatable toothbrush part is configured such that a cylindrical toothbrush part is provided on the outer surface of a cylindrical body. The rotatable toothbrush part support frame is configured such that the cam shafts of the rotatable toothbrush part are fitted into respective cam shaft holes. The vertically moving toothbrush part includes a vertically moving frame that is contained in the internal space of the rotatable toothbrush part support frame, and reciprocates up and down using a vertical moving means.

1. Field of the Invention
The present invention relates generally to a multi-directional toothbrush for protecting teeth and, more particularly, to a multi-directional toothbrush for protecting teeth, which is provided with a rotatable toothbrush part, which vertically and laterally brushes teeth so that the front and rear surfaces of teeth are brushed by vertical movement and the ends of teeth are bushed by rotation, a vertically moving toothbrush part, which operates in conjunction with the rotatable toothbrush part and thus reciprocates up and down, and has side toothbrush parts so that two surfaces of teeth can be simultaneously brushed, and a rotatable toothbrush part support frame, which guides the rotation of the rotatable toothbrush part and is coupled to a toothbrush handle.
2. Description of the Related Art
Generally, a toothbrush is configured such that toothbrush bristles are implanted into a base surface, and thus teeth can be brushed by appropriately moving the toothbrush to conform to the shapes of the teeth. However, there are problems in that brushing takes a lot of time because the front and rear surfaces and ends of teeth must be sequentially brushed, in that the gums can be damaged, and in that it is difficult to brush teeth in the vertical direction of teeth, as is recommended by dentists.

Multi-directional toothbrush for protective teeth


A method of manufacturing a display device includes: preparing a carrier substrate by forming an adhesive layer on a hard glass substrate; forming a flexible substrate on the adhesive layer; forming a thin film transistor and an organic light emitting element on the flexible substrate and encapsulating the organic light emitting element; and separating the carrier substrate and the flexible substrate by irradiating laser light. The adhesive layer is formed on the carrier substrate in such a state that tensile stress is applied. The display device and the carrier substrate are also disclosed.

1. Field of the Invention
The present invention relates to a display device, a method of manufacturing the display device, and a carrier substrate for manufacturing the display device.
2. Description of the Related Art
Recently, display devices have been replaced with portable, thin flat panel display devices. From among flat panel display devices, organic or inorganic light emitting display devices which are self-emissive, have a wide angle of view, a high contrast ratio, and a high response speed are being noticed as next-generation display devices. In addition, an organic light emitting display device which includes an emissive layer formed of an organic material has better luminance, higher driving voltage, and higher response speed than inorganic light emitting display devices, and is capable of representing color images.
A thin display device is manufactured using a flexible substrate which is thin, and thus is likely to be damaged when a single thin flexible substrate is used in the manufacturing process of a flat panel display device. Accordingly, a flexible substrate is adhered to a carrier substrate and then inputted to the manufacturing process for flat panel display devices.
However, when a carrier substrate and a flexible substrate are adhered to each other and then heat is applied thereto, the flexible substrate may deform due to a difference in coefficients of thermal expansion (CTEs) between the carrier substrate and the flexible substrate which are formed of different materials. In particular, when the flexible substrate is deformed, problems may occur in terms of positions and alignment, etc. of each structure to be stacked on the flexible substrate.

Display device, method of manufacturing the display device and carrier substrate for manufacturing display device


A method for diagnosing a pervasive developmental disorder, such as autism, comprising obtaining a sample of cerebrospinal fluid from a subject; obtaining a sample of serum from a subject; testing the cerebrospinal fluid of the subject for a concentration of TNF-α; testing the serum of the subject for a concentration of TNF-α; and positively diagnosing a pervasive developmental disorder when the concentration ratio of TNF-α in the cerebrospinal fluid of the subject to TNF-α in the serum of the subject exceeds approximately 2:1 over normal control concentrations.

1. Field of the Invention
The present invention relates in general to a method for diagnosing a pervasive developmental disorder, for example, autism.
2. Background Art
Since the first clinical descriptions of autism in the 1940s, there has been no definite etiology or pathological finding leading to a cure or reversal of the condition. Recent reports suggest that there may be a combination of environmental or perhaps in utero risk factors, possible autoimmune risk factors, and perhaps localized inflammation of central nervous system neuroglia pointing to a compartmentalized central nervous system inflammatory response in at least some patients with autism.
Although no specific cell count elevation or direct central nervous system antibodies have been found, some recent studies of cytokines in the central nervous system may implicate an isolated response separate from the peripheral immune system.
These studies have not addressed direct neuroglial or innate central nervous system immune responses. The reports of elevated cytokines support possible increased tumor necrosis factor alpha (TNF-α) levels, in that interleukin-6 and elevated levels of TNF-receptor I antibodies have been reported in the cerebrospinal fluid of autistic patients. The role of TNF-α as a neuromodulating agent has been described in brain development as well, and it may play a role in neurons and neuroglial cells modulating glutaminergic transmission. Excessive glutamate excitotoxic effects acting on NMDA receptors could occur in the presence of excess TNF-α. This occurrence can lead to effects on microglial activation as well as other cytokines, such as nuclear factor-kappa-beta (NF-Kβ), among others. Such changes have also been seen in models of inflammation inducing epileptic activity in which neuroglial inflammation has caused epileptic spikes. Because of the high frequency of epileptic spikes seen in some subgroups of autistic children, and given that similar inflammatory mechanisms may play a role in spike formation, this finding may be more than a coincidence.
Vargas D L, et al. Neuroglial activation and neuroinflammation in the brain of patients with autism, Ann Neural 2005; 57:304 and Zimmerman A, et al. Cerebrospinal fluid and serum markers of inflammation in autism, Pediatr Neurol 2005; 35:195-201, disclose measuring cytokine profiles. However, neither article measures TNF-α, much less comparing the levels of TNF-α in cerebrospinal fluid and serum at the same time.
However, to the best of Applicant's knowledge, there are currently no known biological early diagnostic markers to identify at risk patients for a pervasive developmental disorder or to monitor treatment targets.

Method for diagnosing a pervasive developmental disorder


The invention provides a process for hydrotreating an organic feedstock containing thermally unstable compounds and a halogen component by means of contacting the organic feedstock and a gaseous recycle stream containing hydrogen and a hydrogen halide compound with a hydrogenation catalyst in a hydrogenation reaction zone to produce a hydrogenated hydrocarbonaceous stream having a reduced concentration of halogen and a halide compound stream. The resulting effluent from the hydrogenation zone is separated to produce a recycle stream containing a hydrogen halide compound.

The field of art to which this invention pertains is the conversion of organic feedstock which contains thermally unstable compounds and a halogen component to produce hydrocarbonaceous compounds having a reduced concentration of halogen moieties.
There has always been a demand for the conversion or disposal of waste or by-product streams which originate in the petroleum, chemical and petrochemical industries. More particularly, these by-products originate from the chlorination of olefins in the production of epichlorohydrin, propylene oxide and vinyl chloride monomers, for example. It is common in such streams for the predominate species to be halogenated alkanes, but, in addition, in some cases, there are present highly reactive species such as olefins and other thermally unstable compounds that can often polymerize or decompose during processing thereby leading to the plugging of the reactor and its associated piping. This polymerization or decomposition process is the primary mechanism leading to the formation of carbonaceous deposits and the resulting deactivation of the conversion catalyst. Previous techniques utilized to dispose of waste streams containing halogen components, olefins and other heteroatomic compounds have frequently become environmentally unpopular or illegal and, in general, have always been expensive. With the increased environmental emphasis for the treatment and recycle of chlorinated organic compounds, there is an increased need for the conversion of these products when they become unwanted. Therefore, those skilled in the art have sought to find feasible techniques to convert such feedstocks to provide hydrocarbonaceous product streams having a reduced concentration of halogen which may be safely and usefully employed or recycled. Previous techniques which have been employed include incineration and dumping which, in addition to potential pollution considerations, fail to recover valuable hydrocarbonaceous materials and the resulting halogen compounds.

Process for hydrotreating an organic feedstock containing olefinic compounds and a halogen component


The described CAD system enables a drafter to easily enter dimension entities, which describe the physical dimensions of an object in a CAD drawing or model. The dimension entities define either linear, angular, or radial dimensions, and for each dimension entity, the user defines a reference origin in addition to the normal dimensional information. The value of each defined dimension entity may be a simple constant, a parameter, or an expression of multiple constants and parameters. By virtue of the added reference origin, a very complex network of related dimension entities can be simply defined and easily modified. The recalculation of the dimension entities is performed by a parametric dimensioning engine that transforms groups of entities from the global space of the general CAD drawing or model into a local space. While in local space, the parametric dimensioning recalculates the coordinate data of the entities.

The present disclosure relates generally to methods and apparatus for a computer aided drafting and design system, and more particularly, to the representation of objects in such a system. Computer aided design (CAD) systems use computers to assist in the design and testing of parts for a variety of applications ranging from large mechanical structures to tiny integrated circuits. CAD systems are equipped with efficient computer equivalents of many common drawing and drafting tools, thus liberating the user from countless tedious drafting details. An important time saving feature of many CAD systems is that sectional views and other auxiliary views can be automatically generated by the computer from an existing view, and the object being worked on can be automatically resized or rotated.
Typically, the user of the CAD system (the "drafter") enters a visual representation of the object(s) under design into the computer using the interface of the particular CAD system, and the CAD system stores the object(s) and their associated dimensions in a specialized format. The choice of format used to store the object(s) is not a trivial one. In particular, it is desirable to easily manipulate the dimensions of an object, and to easily identify and manipulate groups of related dimension parameters, such as groups of related dimension lines. For example, if one desires to enlarge the 2.times.2 square shown in FIG. 1A to the 4.times.4 square shown in FIG. 1B, one way to do it is to manually change the dimension and the position of each line in the square. Another equivalent way, supported by most CAD systems, is to specify to the CAD system the four lines to be modified, and then to scale the dimension of each line by a factor of two. However, in addition to selecting the four lines, it is also necessary to specify the final position of the scaled square, or a point about which to scale the selected object. Otherwise, merely scaling the lines could result in ambiguous results, as shown in FIGS. 1C and 1D.
As illustrated above, conventional CAD systems may require the drafter, when modifying an object, to tediously manipulate dimension lines of each entity (e.g., lines, circles, arcs, text) of the object, such as the manipulation of the dimension of each line of the square shown in FIG. 1A. Attempts have been made to correlate related dimensions and thus automate the modification of the related dimensions. For example, U.S. Pat. No. 5,548,706 to Koizumi et al. discloses a CAD system for manipulating multiple, parallel dimension lines. In Koizumi et al., the CAD operator selects one of the parallel lines as the "objective dimension line," and defines a reference point of the objective line (defined as beginning, middle, or end) to make subsequent changes. Subsequent changes to the objective dimension line (such as scaling) are also made to the other parallel dimension lines based on the reference point chosen for the objective line. Systems as described in Koizumi et al. are limited, however, in that because only one line is defined as an objective dimension line, only a single parameter can be used to describe multiple dimension lines. Further, the concept described in Koizumi et al. is only applicable to linear dimensions while CAD systems often specify objects with other, non-linear dimensional information such as angular dimensions.
Thus, there is a need for a CAD system method and apparatus which provides the capability to efficiently and conveniently dimension and manipulate related geometrical entities of an object in both two and three dimensions.

Reference based parametric dimensioning method and system


Apparati, methods, and computer-readable media for preventing unauthorized installs and uninstalls of software modules on a computer. One method embodiment of the present invention comprises the steps of amending (41) an uninstall instructions file (32) to include an invention attribute (33) and at least one pre-selected uninstall condition (34); detecting (42) an attempt to open said uninstall instructions file (32); checking (43) the uninstall instructions file (32) for presence of said invention attribute (33); determining (45) whether the at least one condition (34) is satisfied; and aborting (46) the uninstall when at least one condition (34) is not satisfied.

Nefarious individuals often attempt to install unwanted software modules (e.g., Trojan horses) on a user's computer. These unwanted modules can wreak havoc on said computer. Similarly, nefarious individuals often attempt to uninstall useful software modules from a user's computer without the user's consent. An example of an unauthorized uninstall is the case of a hacker uninstalling a protection program such as SymProtect manufactured by Symantec Corporation of Cupertino, Calif. Once the protective umbrella of SymProtect is removed from the computer, it is easier for the hacker to cause damage to other files on the computer. What is needed is a suite of apparati, methods, and computer-readable media by which a user can prevent unauthorized installs and uninstalls of software modules on his or her computer. These needs are satisfied by the present invention.

Preventing unauthorized installs and uninstalls of software modules


A method for fabricating a field emitter electrode includes the steps of: providing an electrolytic solution containing metal ions to an electrolytic bath; providing carbon nanotubes and a cationic dispersant for preventing the agglomeration of the carbon nanotubes to the electrolytic solution; and applying a predetermined voltage to a cathode drum and an insoluble anodic compartment, both of which are immersed in the electrolytic solution, and forming a metal film containing the carbon nanotubes along the surface of the cathode drum.

1. Field of the Invention
The present invention relates to a method for fabricating a field emitter electrode, and more particularly to a method for fabricating a field emitter electrode comprising carbon nanotubes by electrolytic copper plating, and a field emission device produced by using the method.
2. Description of the Related Art
Generally, field emission devices are light sources for emitting electrons in a vacuum environment, and use the principle that electrons emitted from fine particles are accelerated by a strong electric field to collide with fluorescent substances, thus emitting light. Such field emission devices provide superior luminous efficiency and are compact and lightweight, compared to light sources for general illuminators such as incandescent lamps. In addition, since field emission devices do not use heavy metals, unlike fluorescent lamps, they have environmentally friendly advantages. For these reasons, field emission devices have drawn attention as next-generation light sources for various illuminators and display devices.
The performance of field emission devices is mainly determined by emitter electrodes capable of emitting fields. Emitter electrodes currently used to improve electron emission properties have an electrode structure wherein carbon nanotubes (CNTs) are uniformly dispersed and are partially exposed to the surface.
FIG. 1 is a flow chart illustrating a conventional method for fabricating a field emitter electrode comprising carbon nanotubes.
Referring to FIG. 1, the conventional method for fabricating an emitter electrode is initiated by coating an electrode material onto a smooth substrate to form an electrode layer (S11). As the substrate, a metal, glass substrate or the like can be used. A paste of carbon nanotubes and a silver powder in the glassy state is prepared using a suitable resin and a solvent, and is then printed onto the electrode layer (S13). After drying, the resulting structure is subjected to an annealing process to remove the resin and the solvent (S15). The annealed structure is subjected to an additional annealing process, followed by taping, to partially expose the carbon nanotubes to the surface (S17), thereby fabricating the final field emitter electrode.
However, the conventional method has a problem that there is difficulty in uniformly dispersing the carbon nanotubes for the preparation of the paste. Due to this problem, the characteristics of the field emitter electrode may be deteriorated. In addition, sufficient physical and mechanical adherence of the paste to the electrode material cannot be achieved by known paste printing processes.
On the other hand, the conventional method requires the use of a substrate on which an electrode material is coated. Accordingly, when the structure of an emitter electrode needs to be modified in order to produce various field emission devices, there may be limitations depending on the kind of the substrate material used. For example, when an emitter electrode is wound in a cylindrical form to produce a rod-shaped field emission device, the use of a common glass or metal substrate makes modification of the structure of the field emission device difficult.

Fabrication method of field emitter electrode and field emission device produced by using the same


A method for creating test benches for digital circuit design verification (1) partitions a design for purposes of test bench creation according to circuit type, (2) identifies circuit types and creates packaged testing strategies, (3) uses ATPG techniques to create comprehensive test sequences based on the circuit type classifications, and (4) incorporates the ATPG-produced test stimuli and expected responses into the test bench templates.

The invention relates to digital design verification, and more specifically to a method for creating a design verification test bench using automatic test pattern generation (xe2x80x9cATPGxe2x80x9d) and test strategies based on circuit-type classifications.
Test benches for very large scale integrated circuit (xe2x80x9cVLSIxe2x80x9d) designs are difficult and time consuming to create. Additionally, the complexity of circuits is not being fully explored during (non-formal) verification testing. The techniques now being used to create test benches rely on an application of human intuition in the form of waveform editing and test benches written in a hardware description language (xe2x80x9cHDLxe2x80x9d), such as Verilog and VHDL.
These intuitive approaches suffer from the limitations that once plagued manufacturing test generationxe2x80x94the complexity overwhelms most human designers. Testing based on intuition is therefore generally inadequate, is prone to human design error, and takes much too long to create. The efforts of electronic design automation (xe2x80x9cEDAxe2x80x9d) tool designers have been directed primarily at helping the designer to produce larger designs in reasonably short time frames. Only a limited effort has been directed at helping the designer or test bench creator to create more useful test benches in less time. As a result, there is currently an imbalance between what a designer can produce and the ability of anyone to create test benches to adequately verify the design. What are needed are more powerful tools to aid in the creation of test benches.
The current state of the art is to provide rather elaborate assistance with waveform editing and HDL creation of test benches, but few tool makers have presented tools that help the test bench creator produce complex tests automatically, rapidly, in volume, and relatively free of error. The graphical means featured by many of today""s top-flight EDA tools are simply inadequate to the needs of serious designers of large digital circuits. Waveform editing, no matter how user friendly, cannot produce the volume and quality of tests needed for large circuits. Forcing designers to work with these graphical toolsxe2x80x94or, alternatively, requiring the designer to create test stimuli and expected responses using HDL techniquesxe2x80x94slows the entire design process. Also, the graphical techniques rely entirely on human intuition to create test stimuli and expected responses.
The present invention offers a solution to this dilemma. The invention is a test bench creation tool (FIG. 1) that is to be integrated into typical EDA design tool suites, preferably as part of a simulation package. The tool provides a designer with an ability to classify parts of a design using such techniques as special comment lines. Once the parts of a design have been classified in this manner, the tool (or alternatively, the designer) selects pre-existing test bench HDL design templates suitable for the identified circuit classes. These HDL design templates provide much of the boilerplate programming that must exist in any test bench effort. The templates require the tool (or alternatively, the designer) to provide circuit parameters such as bus width, etc. ATPG techniques are available for invocation by the designer to develop tests for combinational logic, and test sequences for sequential logic according to the circuit classifications. The ATPG techniques also create expected responses for use in comparison with actual responses. The tool (or alternatively, the designer) copies the test stimuli and expected responses into the test bench templates to complete the test bench. The completed test benches are applied to the circuits being tested via a simulation tool (FIG. 2).
The ATPG techniques used in manufacturing test are not directly suitable for verification testing and must be modified somewhat to provide useful test bench stimuli. The goal in verification is to demonstrate that the HDL defines a circuit that does what the designer intended it to do, rather than to prove that the HDL does what a fault-free copy of the circuit doesxe2x80x94the latter process sometimes called validation.
The test bench should operate in two modes, (1) a functional verification mode in which a few simple tests are applied to give the designer some assurances that the overall structure operates as intended, without too much attention to detail. A second mode (2) applies detailed tests and expected results to prove that there are no hidden surprises in the design.
Waveforms are useful during the functional verification mode because they rapidly give a designer confidence that the circuit is working properlyxe2x80x94it is important to remember that the goal here is to bring a very large design up to speed as rapidly as possible.
During the detailed mode of operation, waveform inspection is used only when a designer wants to zero in on a specific area, or when comparison with expected results fails.
There is a fundamental problem here that the present invention does not address: the expected results are derived from an analysis of the HDL, so if there is some subtle error in the HDL it won""t be caught by test benches produced in this way. That shortcoming notwithstanding, the present invention is an improvement over much of what is being offered today.

Method for creating a design verification test bench


A fastener is provided for attachment to a workpiece by a friction stir process. The fastener includes a base having an underside adapted to seat upon the workpiece and a fastener portion attached to the top side of the base. An anchor portion projects from the underside of the base and is adapted to be rotated and advanced at high speed and inserted into the workpiece by friction stirring of the workpiece. The anchor portion is embedded in the workpiece upon cooling of the workpiece. The anchor portion has an indent in the surface thereof enabling the softened stirred material to flow into the indent and thereby mechanically capture the anchor portion within the solidified workpiece.

It is known in the automotive industry and in other applications to attach a fastener onto a work piece. The fastener, such as a screw, a nut, a stud, etc., is most conventionally attached by resistance electric welding, and the fastener may have small projections that face toward the metal component so that the electric resistance heating is concentrated at these projections in order to facilitate the formation of the weld between the fastener and the metal component. Hence the process is often referred to as projection welding.
It has also known that a pair of work pieces, such as metal sheets, can be joined together by a friction stir rivet process in which a rivet is spun at high speed and advanced into the work pieces, thereby causing the a region of the work pieces surrounding the rivet to be plasticized and then, upon cooling, the rivet is captured within the cooled metal of the work pieces and thereby attaches the work pieces together. This friction stir riveting process is described in U.S. Pat. No. 6,702,535 assigned to the same assignee as this invention and herein incorporated by reference.

Fastener for attachment by friction stir processing


A method of dechucking a workpiece from an electrostatic chuck. The method adaptively produces a dechucking voltage for canceling any unpredictable residual electrostatic fields between a workpiece and the electrostatic chuck. The method contains the steps of (a) applying a lifting force to the workpiece; (b) altering the chucking voltage; (c) measuring the lifting force; (d) comparing the measured lifting force to a threshold level; and, depending on the result of the comparison, either (e) maintaining the chucking voltage at its present level for a predefined period of time and physically dechucking the workpiece or (f) repeating steps (b), (c), (d) and (e).

1. Field of the Invention
The invention relates generally to electrostatic chucks for holding a workpiece and, more specifically, to a method for releasing a workpiece (such as a semiconductor wafer) from an electrostatic chuck.
2. Description of the Background Art
Electrostatic chucks are used for holding a workpiece in various applications ranging from holding a sheet of paper in a computer graphics plotter to holding a semiconductor wafer within a semiconductor wafer process chamber. Although electrostatic chucks vary in design, they all are based on the principal of applying a voltage to one or more electrodes in the chuck so as to induce opposite polarity charges in the workpiece and electrodes, respectively. The electrostatic attractive force between the opposite charges presses the workpiece against the chuck, thereby retaining the workpiece.
In semiconductor wafer processing equipment, electrostatic chucks are used for clamping wafers to a support pedestal during processing. The support pedestal may form both an electrode and a heat sink as used in etching or chemical vapor deposition (CVD) applications. More specifically, the electrostatic chuck has a layer of dielectric material covering a conductive pedestal base. In a "unipolar" electrostatic chuck, voltage is applied to the conductive pedestal base relative to some internal chamber ground reference. Electrostatic force is established between the wafer being clamped and the electrostatic chuck. When the voltage is applied, the wafer is referred back to the same ground reference as the voltage source. Alternatively, the plasma can reference the wafer back to ground, although some voltage drop occurs across plasma sheaths that form at both the wafer being clamped and the reference electrode.
To cool the wafer during processing, an inert gas such as helium is pumped between the wafer and chuck surface so as to act as a thermal transfer medium to the water-cooled chuck. With helium pressure applied at the wafer-to-chuck interface, a relatively high electric field magnitude is required to generate the necessary electrostatic force required to clamp the wafer. For example, an electrostatic chuck using an alumina dielectric (a dielectric constant of approximately 10) that is operated at a heat transfer gas pressure in the range of 15 to 30 torr requires an electric field magnitude in the range of 0.5.times.10.sup.5 to 1.times.10.sup.5 V/cm. The electric field in a vacuum gap between the wafer and the chuck is higher by the ratio of the dielectric constants of the dielectric material and vacuum. In this example, the ratio is approximately 10 to 1; thus, the electric field in a vacuum gap can be ten times greater than the electric field at the surface of the wafer. Specifically, the resultant electric field can reach 1.times.10.sup.6 to 5.times.10.sup.6 V/cm in the vacuum gap.
Such high electric field magnitudes can cause charging of the dielectric material that may inhibit dechucking of the wafer after processing. In an ideal dielectric, i.e., bound charges only, the high electric field can cause charging of the surface between the wafer and the chuck. The mechanism causing this charging is field emission charging that is made possible by the high electric field reducing the potential barrier height, i.e., overcoming the work functions of the wafer and/or the chuck surface materials, allowing charges to tunnel from the wafer to the chuck surface or vice versa. The amount of charging caused by field emissions depends on the work functions of the surface materials concerned and the effective electric fields at the interface between the surfaces. The induced electric field resulting from field emission charging always opposes the applied electric field, reducing the net electric field and the resultant electrostatic force between the chuck and wafer. However, when the applied electric field is removed, i.e., the chuck voltage is set to 0 volts, a residual electrostatic force remains due to the presence of charge on the surface of the chuck and on the wafer backside surface as a result of the field emission charging. Consequently, dechucking of the wafer may be difficult because the residual electrostatic force must be overcome by a mechanical wafer lift mechanism to remove the wafer from the chuck.
The high electric field magnitude can cause other charging behavior that leads to additional dechucking difficulties. For example, if the chuck dielectric material is not an "ideal" dielectric, i.e., some unbound charge or "free charge" is present, then the free charge can drift through the dielectric material under the influence of the applied electric field. The free charges migrate toward the interface between the chuck and the wafer, producing an increase in free charge density near the surface of the chuck. Depending on the contact resistance between the wafer backside and the chuck surface, the charge may not be able to cross the interface. The result is an accumulation of charge within the dielectric material close to the surface of the chuck dielectric. This charge migration phenomenon depends upon material, time, temperature and electric field magnitude. The result is an effective increase in the electrostatic force at the wafer-to-chuck interface over that of the ideal dielectric. Since both polarization charges and free charges contribute to the electrostatic force, the force increase occurs due to the effective reduction in the separation distance between charges on the wafer backside and charges in the dielectric. However, when the applied electric field is removed, i.e., the chuck voltage is set to 0 volts, a residual electrostatic force remains due to the presence of migrated charges within the chuck dielectric and on the wafer backside surface. As such, the residual electrostatic force increases the physical force necessary to dislodge the wafer from the chuck.
The above effects are two examples of charging phenomenon that occur during electrostatic chuck operation that can affect the ability to dechuck a wafer. In fact, both charging phenomenon can occur on a particular electrostatic chuck depending on the conditions under which the chuck is operated. However, field emission charging and charge migration charging produce competing effects, i.e., field emission charging produces an electric field opposing the direction of the applied field and charge migration charging produces an electric field directed in the same direction as the applied field. For example, a unipolar chuck comprised of a plasma sprayed ceramic such as Al.sub.2 O.sub.3 /TiO.sub.2 dielectric operated in a high density plasma etch process at low temperatures (e.g., -10 degrees Celsius) has a dominant field emission charging phenomenon. Field emission charging reduces the electrostatic force during processing and leads to a residual electrostatic force after removing the applied electrostatic chuck voltage. If the wafer is somehow removed from the electrostatic chuck, and if another wafer is processed using the same chuck, an additional charging of the dielectric occurs. This cumulative charging effect continues until charge saturation occurs at some charge level that depends on the environmental conditions used during processing of the wafers.
Alternatively, if the same chuck is operated at a higher temperature (e.g., +30 degrees Celsius), under the same environmental conditions, then charge migration through the dielectric dominates the residual charging process. The high charge density at the wafer-to-chuck interface that results due to charge migration serves both to increase the applied electric field and to neutralize, to some degree, field emission charging at the chuck surface. The effective electric field and electrostatic force between the electrostatic chuck and the wafer is increased by the charge migration charging effect. However, once the applied chucking voltage is removed, a residual electrostatic force results which inhibits the dechucking of the wafer from the chuck. Because this charging depends on time, electric field strength and temperature, the residual effects are unpredictable. Additionally, the residual charge and force increases from wafer to wafer until some saturation condition is reached.
Consequently, there is a need for a dechucking method that is capable of dechucking a wafer from an electrostatic chuck under any environmental conditions and without damage to the hardware or the wafer being processed. Prior art techniques for dechucking the wafer include (1) setting the applied electrostatic chuck voltage to 0 and waiting some period of time for the wafer and electrostatic chuck to discharge; (2) setting the applied electrostatic chuck voltage to some other fixed voltage, waiting some period of time for the wafer chuck to discharge; (3) using either (1) or (2) followed by forcing the wafer off the electrostatic chuck by a mechanical means that overcomes the residual electrostatic forces; or (4) conductively connecting the wafer to ground by making ohmic contact between the wafer and ground. Methods (1), (2) and (3) suffer from unknown, and possibly very long, waiting periods. On the other hand, method (4) may not work on wafers with insulating backsides and may cause device damage to the wafers.
A significant shortcoming of the conventional approaches to removing the electric charge is that they fail to completely remove the charge such that some residual electrostatic force remains between the wafer and the chuck. This residual electrostatic force necessitates the use of a relatively large mechanical force to separate the wafer from the chuck. The force required for removal sometimes cracks or otherwise damages the wafer. Even when the wafer is not damaged, the difficulty of mechanically overcoming the residual electrostatic force sometimes causes the wafer to dislodge from the chuck unpredictably into a position from which it is difficult to retrieve using a conventional wafer transport robot.
Therefore, there is a need in the art for a method of dechucking a semiconductor wafer from an electrostatic chuck that minimizes the residual electrostatic force between the wafer and the chuck surface.

Method of processing a wafer within a reaction chamber


A multi-stage transmission comprising two planetary gear sets (RS2, RS3) and one planetary reduction gear set (VS), one first clutch (A) and one second clutch (B), one third clutch (E) and one first brake (C), one second brake (D), the external disc carrier of the clutch (B) being connected with one output element of the planetary reduction gear set (VS), the internal disc carrier of the clutch (B) leads to the internal disc carrier of the brake (C) which is connected with one element of the planetary gear set (RS2), the internal disc carrier of the clutch (A) being connected with one output element of the planetary reduction gear set (VS) and the external disc carrier of the clutch (A) with one element of the planetary gear set (RS3), the external disc carrier of the clutch (E) being connected with one input element of the planetary reduction gear set (VS) and with the drive shaft (AN), the internal disc carrier of the clutch (E) being connected respectively with one element of the planetary gear set (RS2) and of the planetary gear set (RS3), the brake (D) being connected with the planetary gear set (RS2) and the housing being connected with one supporting element of the planetary reduction gear set (VS) and the driven shaft (AB) with the planetary gear set (RS2).

In the automatic transmission prior art, particularly for motor vehicles, transmissions comprise planetary gear sets which are shifted by means of friction or shifting elements, such as clutches and brakes, and are usually connected with a starting element, such as a hydrodynamic torque converter or a fluid clutch, subject to a slip effect and optionally provided with a lock-up clutch.
Such a transmission results from EP 0 434 525 A1. It essentially comprises one drive shaft and one driven shaft disposed parallel with each other, one double planetary gear set disposed concentrically to the driven shaft and five shifting elements in the form of three clutches and two brakes, the optional locking of which by pairs determines the different gear ratios between the drive shaft and the driven shaft. This transmission has one planetary reduction gear set and two power paths so that by selective engagement by pairs of the five shifting elements six forward gears are obtained.
In the first power path are needed two clutches for transmitting the torque from the planetary reduction gear set to two elements of the double planetary gear set. These are disposed, axially observed, essentially behind the reduction gear set in direction of the double planetary gear set. In the second power path is provided one other clutch which loosely connects it with one other element of the double planetary gear set. The clutches are arranged here in a manner such that the internal disc carrier constitutes the output.
From the published U.S. Pat. No. 6,139,463 is further known a multi-stage transmission in planetary design, specially for a motor vehicle, which has two planetary gear sets and one planetary reduction gear set, the same as three clutches and two brakes. In this already known multi-stage transmission, two clutches C-1 and C-3 are provided in the first power path for transmitting the torque from the planetary reduction gear set to the two planetary gear sets. The external disc carrier or the cylinder or piston and pressure compensation side of the clutch C-3 is connected with a first brake B-1. Besides, the internal disc carrier of the third clutch C-3 is connected with the cylinder or piston and pressure compensation side of the first clutch C-1, the internal disc carrier of the first clutch C-1 being situated on the output side and connected with a sun gear of the third planetary gear set.
The known multi-stage transmission has the disadvantage that, particularly in the sixth gear, the first brake B-1 is closed. Thereby stands the cylinder of the third clutch C-3 so that no hydrodynamic pressure can build up. In this manner, the pressure compensation space of the third clutch can run idle whereby the shifting quality of the known multi-stage transmission is impaired.
From the published U.S. Pat. No. 6,135,912 is further known a similar multi-stage transmission. In this multi-stage transmission which, likewise, has two clutches C-1 and C-3 for transmitting the torque from the planetary reduction gear set to the planetary gear sets, the internal disc carriers of these clutches are preferably connected with the planetary gear sets. One other embodiment disclosed within the scope of the cited publication provides that the external disc carrier of the clutch C-3 is situated on the output side. This construction, specially the arrangement of the clutches relative to the output or input, has also been disclosed within the scope of U.S. Pat. No. 6,120,410 which also describes a multi-stage transmission of the type mentioned.
The problem on which this invention is based is to propose a multi-stage transmission of the above mentioned type in which the shifting quality is improved. A clutch system is to be specially indicated which, in compact design, makes it possible to implement a quick and comfortable shifting behavior.


The present invention relates to methods of fabricating composite membranes wherein at least one of the components is initially provided in the form of a precursor. The composite material comprising the precursor is processed to transform the precursor and obtain a membrane having a desired property. Including a thermoplastic precursor to a desired component, which itself is less thermoplastic, permits separate pieces of the membrane to be joined by welding or other thermal processes relying on the meltability of the components to achieve a bond. The invention also encompasses fabricating a reinforced ion conducting membrane by melting and mixing a non ion-conducting precursor to an ion-conducting polymer with an essentially inert polymer. The composite material is then processed to transform the non ion-conducting polymer into the ion-conducting form. The mixing of the precursor and the inert polymer may also be achieved by co-precipitating a solution of the precursor and a suspension of the inert polymer; impregnating the precursor onto the walls of the pores of a porous, essentially inert polymer; filling the pores of a porous, essentially inert polymer with a solution comprising a non ion-conducting precursor to an ion conducting polymer and evacuating the solvent to substantially fill the pores of the porous, essentially inert polymer with the precursor; or melting the precursor, filling the pores of a porous essentially inert polymer with the melted precursor and cooling the precursor to form an essentially pore free composite membrane.

The present invention relates generally to the field of ionically conducting separators. The invention particularly relates to methods and processes of fabricating composite membranes especially useful in electrochemical devices requiring a proton conductor such as fuel cells.
The operation of an electrochemical cell requires the occurrence of oxidation and reduction reactions which produce or consume electrons. In operation, an electrochemical cell is connected to an external load or to an external voltage source, and electric charge is transferred by electrons between the anode and the cathode through the external circuit. To complete the electric circuit through the cell, an additional mechanism must exist for internal charge transfer. This mechanism includes one or more electrolytes, which support charge transfer by ionic conduction. Electrolytes must be poor electronic conductors to prevent internal short circuiting of the cell.
One category of electrolytes particularly suitable for use in conjunction with electrochemical cells are proton exchange membranes (PEM). PEMs usually consist of a polymer matrix to which are attached functional groups capable of exchanging cations or aions The polymer matrix generally consists of an organic polymer such as polystyrene, polytetrafluoroethylene (PTFE) or other polytetrafluoroethylene (PTFE) analogs. In general the material is acid with a sulfonic acid group incorporated into the matrix.
The apparent advantages of using PEMs in fuel cells are numerous. The solid electrolyte membrane is simpler and more compact than other types of electrolytes. Also, the use of a PEM instead of a liquid electrolyte offers several advantages, such as simplified fluid management and elimination of the potential of corrosive liquids. In systems using a PEM, the membrane also serves as an electronically insulating separator between the anode and cathode. However, a number of properties are desirable when using an acid ion exchange membrane as an electrolyte. These include: high ionic conductivity with zero electronic conductivity; low gas permeability; resistance to swelling; minimal water transport; high resistance to dehydration, oxidation, reduction and hydrolysis; a high cation transport number; surface properties allowing easy catalyst bonding, and mechanical strength.
Conventional proton conducting membranes for use in polymer electrolyte membrane (PEM) fuel cells consist of homogeneous polymer films. FIGS. 1 and 2 are schematic diagrams depicting three examples of homogeneous polymer films used in polymer electrolyte membranes The polymers depicted in FIG. 1 were developed at DuPont and Dow Chemical Company. These polymers represent a class of compounds known as perfluorosulfonic acids (PFSA). These polymers are fully fluorinated, i.e., all of the sites occupied by hydrogen atoms in a conventional hydrocarbon polymer have been replaced by fluorine atoms. This makes the polymers extremely resistant to chemical attack.
PFSA polymers are generally synthesized by the copolymerization of a derivatized, or active, comonomer with tetrafluoroethylene, (TFE), as illustrated in FIG. 3. After synthesis, the thermoplastic polymer, which is both hydrophobic and electrochemically inert, is converted into the active ionomer by a base hydrolysis process, as illustrated. The result of this step is an ionomer in its salt form. This can be converted to the proton form by ion-exchange with a strong acid. The sulfonate functionalities (Rxe2x80x94SO3xe2x88x92) act as the stationary counter charge for the mobile cations (H+, Li+, Na+, etc.) which are generally monovalent.
Another type of polymer, illustrated in FIG. 2, is a derivatized trifluorostyrene (TFS), of the type developed by Ballard Advanced Materials. This polymer has a fully fluorinated backbone, but some of the side chains have hydrogen atoms.
The polymer is synthesized by copolymerizing derivatized and non-derivitized trifluorostyrene monomers, as illustrated in FIG. 4. This process also produces an electrochemically inactive thermoplastic. In this system the derivatized monomers create the inert sites while the non-derivatized monomers can be sulfonated, as illustrated in FIG. 4. The result of this process is a proton conducting polymer.
Other homogeneous proton conducting polymers are tabulated in Table I. All of these polymers tend to have poor physical properties making them difficult to handle. For example, sheets of the polymers are easily torn or punctured, thereby requiring a minimum usable thickness of about 2 mils (0.002xe2x80x3, 0.05 mm).
In U.S. Pat. No. 5,547,551 Bahar et. al disclose a composite membrane fabricated by filling the void portion of a porous substantially inert polymer membrane with an ionically conducting polymer. This approach starts with a porous membrane fabricated from an inert polymer, such as polytetrafluoroethylene (PTFE) and converts it to an ion conducting membrane by filling the pores with ionomer deposited from solution. This approach leads to thinner membranes, with membranes less than 1 mil (0.001xe2x80x3, 0.025 mm) produced. These membranes are more conductive than pure PFSA membranes on a conductivity per unit area basis, but have lower specific conductivities. The advantage of these membranes is their strength. A 1 mil membrane produced using this technology is tougher than a conventional 5 mil homogeneous membrane.
In U.S. Pat. No. 5,654,109, Plowman et al. disclose an alternate approach to the fabrication of reinforced membranes. In this approach, a core layer of a tough membrane material is clad with surface layers of highly ionically conductive polymer. Typically all of the layers are PFSA type materials, with the core layer having a significantly higher equivalent weight than the surface layers. Although it would seem that the use of a high equivalent weight polymer would significantly impede the proton flux, it has been experimentally determined that a membrane with a core having an equivalent weight as much as 20% greater than the surface layers exhibits a conductivity equivalent to a solid membrane with the composition of the surface polymer.
While the above methods and processes may allow the fabrication of composite membranes that may present enhanced structural stability and ionic conductivity, the methods used do not allow the flexibility needed in fabricating composite membranes suitable for use in a wide range of applications. Thus there is a great need for membranes and membrane fabricating processes that allow greater flexibility in controlling the physical properties of the composite membranes.
The present invention provides a method of making a composite membrane, comprising: (a) combining a first polymer component with a second polymer component; wherein the first polymer component is a non ion-conducting precursor to an ion-conducting polymer; and (b) converting the first polymer component from the non ion-conducting precursor to the ion- conducting polymer.
The combining of the polymeric components may comprise melting and mixing the polymers, co-polymerizing two or more monomers, co-precipitating a solution of a first polymer and a suspension of a second polymer, filling the pores of a porous polymeric matrix with a solution of a second polymer, or filling the pores of a porous polymeric matrix with a melted polymer.
The invention encompasses a process wherein the step of combining the first and second polymer components comprises mixing a solution of the first component and a suspension of the second component, co-precipitating the first and second polymer components to form a gelatinous mass, and drying the gelatinous mass. The dried gelatinous mass may further be sintered and/or pressed into a sheet, optionally at temperatures of about 150xc2x0 C. or about 300xc2x0 C. Pressing the gelatinous mass into a sheet may be achieved by rolling the mass.
The processes of the invention may also combine the first and second polymer components by forming a solution of the first polymer component, filling the pores of the porous matrix with the solution; removing the solvent from the pores of the matrix to form an essentially pore-free composite material. Alternatively, the first and second polymer components may be combined by melting the first polymer component, filling the pores of the porous matrix with the first polymer component, and cooling the polymer to form an essentially pore-free composite material.
The composite membranes formed by the processes of the invention may comprise regions essentially made of the first polymer component and regions essentially made of the second polymer component. Further, the first polymer component may form an ion-conducting path, generally a hydrophilic path capable of transporting ions through the membrane.
The invention also encompasses a method of making a composite membrane, comprising: (a) initiating a living chain co-polymerization of a first monomer and a second monomer, wherein the first monomer is a non-derivatizable monomer and the second monomer is a non ion-conducting precursor to an ion-conducting monomer; (b) propagating the polymerization to form a co-polymer chain comprising a given number of non-derivatizable monomers and a given number of precursor monomers; (c) fabricating a membrane from the co-polymer chain; and (d) transforming at least a portion of the non ion-conducting precursor monomers into ion-conducting monomers. The non-derivatizable monomers and precursor monomers may be randomly distributed along the co-polymer chain. Depending on the application of the composite membrane, the number of non-derivatizable monomers in the co-polymer chain may be greater or lower than the number of precursor monomers in the co-polymer chain. The process of the invention allows the fabrication of composite membranes wherein the co-polymer chain comprises regions wherein most or all of the monomers are non-derivatizable monomers and regions wherein most or all of the monomers are precursor monomers or ion-conducting monomers obtained by transforming precursor monomers. The regions comprising precursor monomers or ion-conducting monomers obtained by transforming precursor monomers may form an ion-conducting path, generally a hydrophilic path capable of transporting ions through the composite membrane.
Finally, the processes of the invention are applicable to any combination of polymeric components as well as combination of a polymeric component and a non polymeric component. For example, the first component may be a precursor to an ion conducting polymer component selected from long side chain perfluorosulfonic acid, short side chain perfluorosulfonic acid, trifluorostyrene, partially derivatized trifluorostyrene, polystyrene, and mixtures thereof The second polymer component may be a substantially inert polymer selected from polytetrafluoroethylene (PTFE), perfluoroalkoxy derivative of PTFE (PFA), fluorinated ethylene-propylene copolymer (FEP), polyvinyl chloride, polyvinyl dichloride, polyvinyl fluoride (PVF), polystyrene, polytrifluorostyrene (TFS), polyetherketone, polyethersulfone, polyparaphenylene, and mixtures thereof. When the second component is a porous matrix, the second component may be an inorganic material selected from fiber glass, fibrous quartz, rock wool, fibrous alumina, fibrous silica, or other fibrous silicates or alumino-silicates, and mixtures thereof.


A one part curable adhesive composition that includes a multifunctional (meth)acrylate oligomer the homopolymer of which has a glass transition temperature (Tg) of at least 100° C., and a first (meth)acrylate monomer exhibiting a viscosity of no greater than 1000 centipoise (cP) at 25° C., the first (meth)acrylate monomer being at least one of a (meth)acrylate monomer whose homopolymer has a Tg of at least 100° C. and (alkoxy) tetrahydrofurfuryl (meth)acrylate, the curable adhesive composition exhibiting a viscosity of no greater than 100,000 cP when measured at 25° C. and a shear rate of 20 sec−1.

The invention is directed to formulating low temperature curable adhesive compositions that exhibit relatively high glass transition temperatures.
A variety of adhesive compositions are used as structural adhesives in electronic devices. However, it is often difficult to form a good adhesive bond to the types of substrates that are present in electronic devices. Such substrates include polycarbonate, alumina, metal and glass. In addition, many adhesive compositions must be heated to elevated temperatures to form good adhesive bonds. Many components in electronic devices are sensitive to heat and heating such components might cause the components to soften or melt or might impair or destroy the functionality of the component.
Thermally reactive adhesive compositions that are cured at low temperatures often exhibit low glass transition temperatures (Tgs). Adhesives that exhibit relatively low Tgs tend to exhibit poor performance reliability when used as structural adhesives. Adhesives that exhibit relatively high Tgs tend to exhibit good performance reliability when used as structural adhesives. To obtain a cured composition that exhibits a high Tg using a thermally reactive adhesive composition, it is often necessary to initiate the cure at a high temperature. Such temperatures often exceed 100° C. Curing an adhesive composition at a temperature greater than 100° C. while it is present in an electronic device might melt a component of the device or destroy the functionality of the device. Therefore, there is a need for a thermally curable adhesive composition that can be cured at a relatively low temperature, exhibit a relatively high Tg, and form good adhesive bonds to substrates such as polycarbonate, alumina, glass, and metal.

Low temperature curable adhesive composition and articles including the same