Semiconductor devices including a first transistor and a second transistor are integrated on a substrate. Each of the first and second transistors include a nano-sized active region including source and drain regions provided in respective end portions of the nano-sized active region and a channel forming region provided between the source and drain regions. The source and drain regions of the first transistor have the same conductivity type as those of the second transistor, and the second transistor has a threshold voltage lower than that of the first transistor. The channel forming region of the second transistor may include a homogeneously doped region, whose conductivity type is the same as the source and drain regions of the second transistor and is different from the channel forming region of the first transistor.

Example embodiments of the inventive concepts relate to semiconductor devices, and in particular, to semiconductor devices with transistors whose threshold voltages are different from each other.
Semiconductor integrated circuit devices are increasingly being used in consumer, commercial and other electronic devices. The semiconductor devices can include a memory device for storing data, a logic device for processing data, and a hybrid device including both of memory and logic elements. Due to the increased demand for electronic devices with fast speed and/or low power consumption, the semiconductor devices should provide a fast operating speed and/or a low operating voltage. To satisfy these technical requirements, the complexity and/or increased integration density of semiconductor devices may increase.

Integrated junction and junctionless nanotransistors


A wireless communication method and a wireless communication system wherein any communication interruption caused by changing RRB arrangement information can be avoided. In ST301, Node B (100) transmits informative information including the RRB arrangement information and RRB arrangement version. In ST302, UE (200) holds the RRB arrangement information and RRB arrangement version included in the informative information received from Node B (100). In ST303, UE (200) creates CQI information including both a CQI report value, which is calculated by use of the held RRB arrangement information, and the held RRB arrangement version. In ST304, UE (200) transmits the CQI information to Node B (100). In ST305, Node B (100) performs a scheduling based on the RRB arrangement information determined from the RRB arrangement version included in the received CQI information. In ST306, Node B (100) transmits the scheduling information to UE (200).

In recent years, in LTE (Long Term Evolution), carrying out channel definition in the physical layer according to scheduling differences is studied. As specific examples of this channel definition, there are channels such as the localized channel and the distributed channel based on the OFDM system.
FIG. 1 is a conceptual diagram of the localized channel and the distributed channel in the frequency domain. In FIG. 1, blocks 1, 2 and 3 show the distributed channel and blocks 4, 5, 6, . . . , 29 and 30 show the localized channel. Further, in this figure, three subcarriers are assigned to one block of the localized channel. Hereinafter, this block will be referred to as "RRB (Radio Resource Block)."
The localized channel refers to a method of assigning RRB's to users in the frequency domain and the time domain in a concentrated manner, and is directed to improving throughput by scheduling by assigning only RRB's of good received quality to users. Further, the operation of UE's includes measuring received power per RRB (in FIG. 1, blocks 4, 5, 6, 29, and 30) which is arranged in the localized channel, and calculating and reporting the CQI of each RRB, and Node B reports the scheduling result to UE's using RRB numbers.
On the other hand, the distributed channel refers to assigning RRB's in the frequency domain and the time domain in a distributed manner, and is directed to providing stable quality to users by obtaining frequency and time diversity. Further, the operation of UE's include calculating and reporting the CQI based on average full band received power, and Node B reports the scheduling result to UE's using RRB numbers.
In this way, first, UE's report the CQI's in RRB units (in the case of the localized channel) and are assigned schedulings in RRB units, and so need to learn how RRB's are arranged, that is, learn RRB arrangement information.
Next, the characteristics of the localized channel and the distributed channel will be described. The localized channel assigns high quality frequency band and time to users, and so high speed communication can be anticipated. Further, the localized channel needs to report the CQI's per RRB frequently, and, for this reason, cannot be applied to UE's which receive significant fading variation. In view of these, the localized channel is suitable for massive downloading services such as web browsing and is preferably used for users who are not moving at a high speed.
On the other hand, with the distributed channel, high speed communication cannot be anticipated but frequency diversity and time diversity can be obtained, so that stable communication can be anticipated. Further, the frequency of CQI report can be reduced compared to the localized channel. For this reason, the distributed channel does not carry out high speed transmission, but is suitable for services such as speech requiring stable quality, and so is preferably used for users when scheduling functions do not work effectively because users move fast.
In this way, uses are different between channels. For this reason, if the arrangement of the localized channel and the distributed channel is fixed, the distributed channel is likely to be assigned to users originally suitable for the localized channel, or, on the other hand, the localized channel is likely to be assigned to users originally suitable for the distributed channel. Therefore, the arrangement of the localized channel and the distributed channel is preferably variable.
The arrangement pattern of the localized channel and the distributed channel may be changed, for example, in the case where, for UE's in the same cell, the distributed channel is assigned to 20% of the UE's and the localized channel is assigned to the rest of 80% of the UE's (which is shown in the upper part of FIG. 2), and, in the case where the distributed channel is assigned to 10% of the UE's and the localized channel is assigned to the rest of 90% of the UE's (which is shown in the lower part of FIG. 2).    Non-Patent Document 1: "Downlink Channelization and Multiplexing for EUTRA," Samsung, 3GPP TSG RAN WG1 Ad Hoc on LTE, R1-050604, Sophia Antipolis, France, Jun. 20 to 21, 2005.    Non-Patent Document 2: "Radio Resource Control (RRC) Protocol Specification," 3GPP TR25.331

Wireless communication base station apparatus, wireless communication mobile station apparatus, wireless communication method, and wireless communication system


A thermal treatment furnace is described in which gas leakage does not occur during thermal treatment at a high temperature. A thermal treatment furnace having a reaction tube is provided with an opening at one end and a flange surrounding the opening and covered by a cap abutting on the reaction tube at the flange to cover the opening. The flange is provided with a feature which introduces an inert gas to provide back pressure into the joint portion between the flange and the cap, thus preventing reaction gas from leaking to the outside of the furnace through the gap between the flange and the cap. The flange may be further modified to discharge gas under back pressure from between the joint surfaces of the flange and the cap to prevent the inert gas from affecting the reaction in the tube.

The present invention relates generally to a thermal treatment furnace and, more particularly, to a thermal treatment furnace having a function of preventing a gas in the furnace from leaking to the outside. The term xe2x80x9cthermal treatmentxe2x80x9d used in this specification widely means that an object is heated for treatment in a gas atmosphere, and includes the case where a chemical reaction such as oxidation or reduction takes place.
FIG. 1 illustrates a cross-sectional view of a conventional thermal treatment furnace. A thermal treatment furnace 10 includes a reaction tube 1 and a cap 2. The cap 2 closes an opening 3 of the tube 1 to confine a gas in the tube 1. The tube 1 has a supply port 4 and an exhaust port 5 for a reaction gas. The reaction gas goes to the supply port 4 from a gas supply apparatus (not shown) through a pipe, and is supplied into the tube 1. The gas going out through the exhaust port 5 is treated by a gas treatment apparatus (not shown) and is exhausted. Within the tube 1 are mounted objects 6, for example, semiconductor substrates such as silicon wafers. The interior of the tube 1 is heated by a heater (not shown) provided inside or outside the tube 1.
FIG. 2 is an enlarged view of the portion of a conventional thermal treatment furnace indicated by symbol A in FIG. 1. In the case where the treatment temperature increases to a high temperature of about 800xc2x0 C. or higher, an O-ring for sealing cannot be used at a joint portion between the tube 1 and the cap 2. This is because the heat resistance of the O-ring is low. Therefore, as shown in FIG. 2, a small gap 7 is undesirably produced at the joint portion between the tube 1 and the cap 2, and a problem arises in that the gas in tube 1 leaks through this gap (reference numeral 7 in FIG. 2). Especially when the leaking gas is a highly reactive (corrosive) gas, it has a greatly adverse influence on an external environment. Therefore, a thermal treatment furnace without gas leakage during high-temperature thermal treatment is demanded.
An object of the present invention is to provide a thermal treatment furnace without gas leakage even at the time of high-temperature thermal treatment.
A thermal treatment furnace in accordance with the present invention is characterized by having a reaction tube provided with an opening at one end thereof and a flange surrounding the opening, and a cap abutting on the reaction tube at the flange to close the opening, and including means for preventing a gas in the reaction tube from leaking to the outside through a gap formed at the joint portion between the flange and the cap and further including means for discharging a leaking gas in the gap between joint surfaces of the flange and the cap.
Also, the thermal treatment furnace in accordance with the present invention is characterized in that the flange of the reaction tube constituting the thermal treatment furnace has a groove and a hole for supplying an inert gas into the gap between the joint surfaces of the flange and the cap, and that the flange further has a groove and a hole for discharging the leaking gas passing through the gap between the joint surfaces of the flange and the cap.
The novel features believed to be characteristic of this invention are set forth in the appended claims. The invention itself, however, as well as other objects and advantages thereof, may be best understood by reference to the following detailed description of an illustrated preferred embodiment to be read in conjunction with the accompanying drawings.

Thermal treatment furnace having gas leakage preventing function

International Business Machines Corporation


A semiconductor device has a dielectric strength for a gate oxide film at a trench bottom that is higher than that of side walls used for channels. An n+0 type substrate 1 having substrate plane orientation of (110) is prepared, and the side walls of a trench where channels are formed are in (100) planes. The other, non-channel forming, side walls of the trench are in (110) planes. Thus, the growth rate of the gate oxide film 7 in the non-channel forming side walls and the trench bottom is faster than that in the channel forming side walls. As a result, the film thickness at the non-channel-forming side walls and the trench bottom is greater than that of the channel-forming side walls. Accordingly, the device has high mobility, and there is no drop of dielectric strength due to partial reduction of the thickness of the gate oxide film 7. This achieves both a reduction of the ON resistance and an increase in the dielectric strength of the semiconductor device.

This application relates to and incorporates by reference Japanese Patent application No. 2001-29975 filed on Feb. 6, 2001.
The present invention relates to a trench gate type semiconductor device where a trench gate is formed on a silicon wafer and to a method of manufacturing a trench gate type semiconductor.
A silicon substrate including a substrate surface in a (100) plane orientation and an orientation flat in a (110) plane orientation has been used for manufacturing an insulated gate type semiconductor device such as a MOSFET, an IGBT or the like where a gate electrode is located within a trench.
In this case, since the trench of a trench gate usually has parallel side walls that are perpendicular to the orientation flat, the side walls are located in (110) planes. However, since mobility at a (110) plane is lower than that at a (100) plane, when a channel is formed at a (110) plane, the channel resistance is relatively high, which undermines the goal of reducing the ON resistance of elements.
Therefore, as explained in Japanese unexamined patent application publication (JP-A) No.H2-46716, the side wall surface of a trench gate is located in a (100) plane, which results in higher mobility, and the channel resistance is reduced, which reduces the ON resistance. This is done by using a silicon substrate having a surface in a (100) plane and an orientation flat in a (100) plane.
It is widely known that the growth rate of an oxide film is dependent on the plane orientation when a silicon oxide film is grown through thermal oxidation of silicon. Such dependence is shown in FIG. 7. As indicated by this figure, mobility is relatively high but the oxidation rate is the lowest at the plane (100). On the contrary, mobility at the planes (111) and (110) is lower than that at the plane (100) but the oxidation rate at these planes is higher.
In the trench described in unexamined patent publication (JP-A) No.H2-46716, the side walls and the trench bottom, where the channel is formed, are all located in (100) planes, thus the mobility at each plane in the trench is high and the growth rate of oxide film formed at each plane is does not vary from one surface of the trench to another.
It is preferred that the dielectric strength of a gate oxide film formed within the trench be higher at the trench bottom than that at the side walls, since the side walls are usually used to form a channel. However, when an effort is made to improve the dielectric strength of the film at the trench bottom by increasing the thickness of the film at the bottom, the thickness of the film at the side walls also increases, and the ON resistance of the element increases.
Thus, when the plane orientation is like that in unexamined patent publication (JP-A) No.H2-46716, there is an advantage with regard to the dielectric strength because the gate oxide film thickness of the side walls and the bottom, which are used as the channel, are identical due to the dependence on the plane orientation of the growth rate of the oxide film.
However, if the aspect ratio of the trench is high, for example, when the trench depth is 15 xcexcm or more, less oxidation gas is supplied to the trench bottom during thermal oxidation, and the film thickness 15 at the bottom of the side walls is less than the film thickness 14 at the area near the opening of the trench 51. Thus, the film thickness 16 at the trench bottom is relatively low as shown in the cross-sectional view of the gate oxide film 50 of FIG. 8A. In the case of an element oriented like the MOS transistor proposed in the unexamined patent publication mentioned above, the reduction of the thickness of the gate oxide film at the trench bottom part is significant because the trench gate is deeper, for example, deeper than 15 xcexcm or more, for reducing the ON resistance.
As explained above, when forming a trench gate on a silicon substrate that has a surface in a (100) plane and an orientation flat in a (110) plane, the growth rate at the bottom of the trench 51, which is in a (100) plane, is low, as shown in the cross-sectional view of the gate oxide film 50 of FIG. 8B. Thus, this arrangement is disadvantageous with regard to dielectric strength.
Considering the background above, it is an object of the present invention to provide a trench gate type semiconductor device in which the dielectric strength of a gate oxide film is higher at the trench bottom than at a pair of side walls that are used for forming a channel.
The invention is basically a trench gate type semiconductor device that includes a silicon substrate, in which semiconductor layers are formed. The silicon substrate includes a main surface and a rear surface, the rear surface being opposite to the main surface. The main surface is in a (110) plane. A trench is formed in the semiconductor layers, and the trench has at least a first pair and a second pair of opposed sidewalls, and the first pair of sidewalls are in (100) planes. A gate oxide film, which is formed by thermally oxidizing the walls of the trench, coats the surfaces of the trench. A gate electrode is located on the gate oxide film inside the trench, and channels are formed at the first pair of side walls when a predetermined voltage is applied to the gate electrode.
The invention includes a method, which basically includes preparing a silicon substrate that includes semiconductor layers. The substrate has a main surface and a rear surface. The main surface is opposite to the rear surface and is oriented in a (110) plane. The method further includes forming a trench in the semiconductor layers, such that the trench has at least a first pair and a second pair of opposed sidewalls, and the first pair of sidewalls are in (100) planes. A gate oxide film is formed by thermally oxidizing the walls of the trench. Then, a gate electrode is formed on the gate oxide film inside the trench such that channels are formed at the walls that are in (100) planes when a predetermined voltage is applied to the gate electrode.

Trench gate type semiconductor device and method of manufacturing


There are provided a receiver and a transmitter-receiver in which an automatic gain control loop is promptly performed and even in the case of a modulated wave having information in its amplitude, wave distortion can be eliminated. A received signal is received by an antenna and is amplified by a power amplifier. The gain of the received signal is attenuated by a variable attenuator in accordance with an output voltage of a holding circuit. After the signal is converted to an intermediate-frequency signal and amplified through a common procedure and detected, a comparator compares an output signal of the detector and a reference voltage V.sub.ref, and obtains a signal indicating whether the output signal exceeds a reference voltage or a differential voltage therebetween. When the output signal or the differential voltage is brought to a positive level, a timing signal generating section generates a timing signal T.sub.m, and the holding circuit holds a detection signal. In the variable attenuator, the signal is attenuated in accordance with the detection signal. Thereafter, output of the detector is integrated in a time constant circuit, and addition of respective outputs of the time constant circuit and the holding circuit is performed in a computing unit.

1. Field of the Invention
The present invention relates to an attenuator controlling circuit provided in radio equipment such as a receiver or a transmitter-receiver, in which a time division multiple access (TDMA) system is adopted.
2. Description of the Related Art
In a TDMA system, a base station performs transmitting and receiving operations to and from a mobile station in accordance with a transmit-receive frequency assigned to the mobile station, and with a receiving slot and a transmitting slot within a frame. In this case, the receiving electric field varies according to the distance between the base station and the mobile station. For this reason, in order to prevent saturation of the receiving electric field and obtain the maximum output for a base band processing section, an attenuator is controlled such that the receiving power thereof is kept constant so as to cope with a change in the receiving electric field.
FIG. 2 is a functional block diagram of a conventional receiver in a base station.
In the receiver shown in this drawing, a signal inputted from an antenna 1 is amplified by a power amplifier 2 at a fixed gain, and the output is attenuated in a variable attenuator 3 in accordance with an output voltage of a comparator 12 which is considered to be a control signal.
Frequency conversion is carried out by a mixer (which will be hereinafter referred to as MIX) 4 and a local oscillator 5. The input signal is converted to an intermediate frequency lower than that of the input signal, and the frequency band is limited by a band pass filter (which will be hereinafter referred to as BPF) 6. Frequency conversion is further carried out by a local oscillator 8 and MIX 7, and the frequency band is further limited by BPF 9.
The thus obtained signal is amplified in a limit amplifier (which will be hereinafter referred to as LIM amplifier) 10 at a fixed gain up to an amplitude in which base band processing is allowed, and a modulation envelope is detected at a detector 11. A differential voltage between an output of the detector 11 and a reference voltage V.sub.ref, which indicates power in which LIM amplifier 10 is not saturated, is obtained in the comparator 12. The gain of the received signal is attenuated by the variable attenuator 3 with the thus obtained differential voltage as the control voltage. Through the above-described process, the received signal is controlled in a fixed receiving electric field.
However, the conventional receiver has the following drawbacks.
When the signal is controlled in the fixed receiving electric field of the receiver as described above, there exists a drawback in that a modulated signal such as a .pi./4-shift QPSK signal, which has information in its amplitude, loses amplitude information and is thereby not demodulated correctly.
In order to overcome the above drawback, there has been adopted a method in which an output of the detector 11 is integrated by a time constant circuit, and a timing for synchronization with a TDMA frame is controlled by a timing signal generating means in a control section so as to control a gain to be attenuated in the variable attenuator 3. However, in this method, when there is no burst wave, the gain to be attenuated in the variable attenuator 3 is 0 dB. For this reason, when the burst wave is thereafter inputted, an input modulated signal is greatly amplified. When the receiving electric field of the burst wave is large, saturation is caused. In addition, since integration of the output of the detector 11 is effected by the time constant circuit, more time for integration is required. As a result, there exists a drawback in that an AGC (Automatic Gain Control) loop cannot respond, and a head portion of the input signal is thereby distorted.

Receiver and transmitter-receiver having variable attenuator to avoid saturation by a strong signal


A method for determining a malfunction of a pressure sensor determines that a stick malfunction occurs in the pressure sensor by an ECU calculating a difference between a maximum value and a minimum value of a voltage value output from the pressure sensor mounted in a fuel tank and determining that a malfunction has occurred in a case that the difference is less than a predetermined value.

(a) Field of the Invention
The present invention relates to a method for determining malfunction of a pressure sensor. More particularly, the present invention relates to a method for determining malfunction of a pressure sensor in a fuel tank.
(b) Description of the Related Art
Generally, a pressure sensor is mounted in a fuel tank for measuring a pressure of a fuel evaporation gas therein and detecting a leakage of the fuel tank. Evaporation gas in the fuel tank is captured in ordinary times and, when an engine starts, the evaporation gas is transmitted to a surge plenum and ignited in the engine.
Malfunctions of the pressure sensor mounted in the fuel tank include a malfunction by disconnection of a circuit of the sensor, a malfunction by a short, and a stick malfunction. The stick malfunction means that a voltage output from the sensor is locked up as one value because of an error occurrence of a current circuit in the sensor.
According to a method for determining malfunction of a pressure sensor of the prior art, the malfunction by a disconnection of a circuit of the sensor and the malfunction by a short can be determined but the stick malfunction cannot be determined.
Therefore, in a case that the fuel leaks from the fuel tank, when there is a stick malfunction the sensor determines that the fuel does not leak and thus the sensor outputs an error value. Therefore a problem occurs in that the leakage is not detected. In addition, in a case that the fuel does not leak from the fuel tank, when there is a stick malfunction the sensor determines that the fuel leaks and so the sensor outputs an error value. Therefore a problem occurs in that an engine warning lamp is erroneously turned on.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Method for determining malfunction of pressure sensor


An apparatus for transporting a sheet recording medium (12) has an entrance drive roller (16) paired with a corresponding entrance pressure roller (18) to form an entrance nip (14) for transporting the sheet recording medium (12) into a scanning section (20) between the entrance nip (14) and an exit nip (24). The exit nip (24) is formed by an exit drive roller (26) with a corresponding exit pressure roller (28) for transporting the recording medium (12) out from the scanning section (20). At each end of the entrance pressure roller (18), an entrance pressure roller actuation arm (120) actuates the entrance pressure roller (18) to exert variable force against the entrance drive roller (16). At each end of the exit pressure roller (28), an exit pressure roller actuation arm (130) actuates the exit pressure roller (28) to exert variable force against the exit drive roller (26).

Nip-fed sheet media transport systems using paired rollers are widely used in various printing applications. In a nip-fed system, a drive roller is pressed against a backing roller to form a nip and provides drive motion at the nip. A nip-fed transport can be engineered to perform with a suitable degree of accuracy in devices such as printers and office copiers. However, conventional nip-fed media transport mechanisms do not provide sufficient precision for imaging applications that require high resolution. For example, many types of medical imaging apparatus print onto a sheet of recording medium at resolutions well exceeding 600 dots per inch. For such devices, a sheet media transport must provide extremely accurate motion when moving the sheet through the image recording mechanism. This problem becomes even more pronounced with full-sheet imaging, in which little or no margin is to be provided at the leading or trailing edges of a sheet. As is well appreciated by those skilled in media transport arts, the dynamics of handling and urging a sheet of recording medium through a printing mechanism can be much more complex at the leading and trailing edges that along more central portions of the sheet.
Dual nip apparatus provide advantages where it is necessary to provide more precise motion control for sheet media. By using two pairs of rollers in series along the transport path, a more stable sheet media transport is provided, since the motion of the medium is controlled through at least one nip at any point during the image recording process. FIG. 1 shows, in schematic form, a conventional dual nip transport apparatus 10 as used for a sheet of recording medium 12. In the travel path, recording medium 12 is fed through an entrance nip 14 formed between an entrance drive roller 16 and a pressure roller 18, then through an exit nip 24 formed between an exit drive roller 26 and a pressure roller 28. Image data is recorded by a printhead 56, or other type of write head or recording head, that records the image onto recording medium 12 as it is progressively scanned through an imaging area 20 between entrance nip 14 and exit nip 24. Typically printhead 56 is a scanned point source, such as a laser or other source of electromagnetic radiation, that is scanned across recording medium 12 in a direction orthogonal to the direction of motion Q. In order to provide uniform speed with dual nip media transport apparatus 10, it is necessary to couple the speed of entrance drive roller 16 at entrance nip 14 with the speed of exit drive roller 26 at exit nip 24. The conventional method for coupling rotation of entrance and exit drive rollers 16 and 26 is using a belt 22, as shown in FIG. 1.
Dual nip transport devices such as dual nip transport apparatus 10 in FIG. 1 perform sufficiently well for many types of imaging applications. However, dual nip transport arrangements using conventional design approaches fall somewhat short of performance levels needed for high-resolution medical imaging applications. One notable type of problem relates to transitions as the sheet medium moves through the entrance and exit nips, particularly at leading and trailing edges of a sheet. At certain points in the transport cycle, the sheet medium goes through a transition between being held in one nip and being held in both nips. As the sheet edge enters or exits a nip, any abruptness in handling can cause a corresponding effect on the image recording operation.
Thus, it can be seen that there is a need for a transport mechanism that provides precision handling of single sheet media at a constant transport speed, allowing full sheet scanning and imaging from leading to trailing edge and minimizing the effects of transitions at leading and trailing edges.

Actuated pressure roller in media transport


A device for determining the weight per unit area of a moving material web, in particular a fibrous material web includes at least one microwave sensor that has an element for coupling the microwaves and a reference element. The coupling element and the reference element are located at a distance from one another in such a way that the material web can be moved therebetween. At least one microwave sensor element, the coupling element and/or the reference element can be moved such that the distances between the material web and the elements can be adjusted for or during the measurement of the moving material web.

1. Field of the Invention
The present invention relates to a device and a method to determine the basis weight of a moving material web, in particular a fibrous web, including at least one microwave sensor which has an element for coupling the microwaves and a reference element, whereby the coupling element and the reference element are located at a distance from each other in a manner that the material web can be moved between them.
2. Description of the Related Art
Basis weight is generally understood to be the total weight of, for example a fibrous web, in other words the weight of all fibrous web components such as fibers, ash and water together. The fibrous web may be a paper web, tissue web or cardboard web.
Previous measurement technologies are usually based on the absorption of health hazardous radioactive radiation, so that such a measurement is always connected with considerable regulatory constraints.
The fundamental measuring principle is already known for example, from patent specification U.S. Pat. No. 4,755,678 by J. R. Izatt et. al. "Simultaneous measurement of moisture content and basis weight of paper sheet with sub-millimeter laser", or from the publication by E. Nyfors and P. Vainikainen "Industrial Microwave Sensors", published by Artech House Norwood 1989. One characteristic of such measurements is that the measurement signal is subjected to extreme intrinsic distance sensitivity.
Patent application EP 1 703 275A1 discloses a measuring device and a measuring method, and describes a microwave measurement which indeed considers this fact by measuring the distance and an appropriate signal correction, whereby the thus obtainable measurement results are too imprecise in practice.
What is needed in the art is a device and a method to determine the basis weight of web materials, which allows for a more precise basis weight measurement on a moving material web, using microwave radiation.

Determination of basis weight of a material web using a microwave sensor, whereby the distance between the material web and the surfaces of the microwave sensor is being adjusted to a constant value by air cushions


A pressure control valve in which the mass to be moved by the diaphragm is reduced by providing that a valve seat body having a valve seat face is placed in a middle region of the diaphragm. When the valve seat face lifts away from the valve closing body, fuel to be diverted flows from the pressure control side of the diaphragm to the return side of the diaphragm, via the valve seat face and a return conduit The pressure control valve is especially suitable for use in fuel supply systems of internal combustion engines.

The invention is based on a pressure control valve for an internal combustion engine. A pressure control valve is already known (U.S. Pat. No. 5,078,167) that is disposed on a fuel filter of a fuel supply system for an internal combustion engine and that has a base body in the middle region of which a tubular valve seat body with a valve seat face is secured. Between the base body and the valve seat body, a diaphragm is fastened firmly into the middle region, its periphery being fastened to a flange of the base body. A fuel inlet neck protrudes with great play into the valve seat body and is connected to the pressure side of the fuel feed pump. Some of the fuel flowing via the fuel inlet neck reaches the valve seat body and from there passes through the filter cloth of the fuel filter and after that, via an opening in the base body, acts on a pressure control side of the diaphragm. Connected to the return side of the diaphragm, remote from the pressure control side of the diaphragm, is a valve closing body, which in sealed fashion surrounds the fuel inlet neck and is displaced on the diaphragm by a motion of the diaphragm, so as to be lifted more or less away from the valve seat face of the valve seat body, counter to the force of a compression spring engaging the return side of the diaphragm. Such a pressure control valve is very complicated in design and because of the friction resulting from the sealing of the valve closing body on the fuel inlet neck, there is undesirable hysteresis and imprecision of control. Moreover, the valve closing body has a very large mass, which must be moved by the diaphragm fastened in its middle region and on its periphery firmly to the base body, and as a result the reaction speed of the pressure control valve to pressure changes is also impaired.
A pressure control valve is also known (U.S. Pat. 4,300,510) that is disposed on a fuel distributor line. A diaphragm of the pressure control valve is fastened on its periphery between an annular flange and the cap and in its middle region supports a valve closing body, which cooperates with a flat valve seat face on a valve seat body protruding into the fuel distributor line. A compression spring is supported on the side of the diaphragm remote from the valve seat body and on its other end rests on the cap. The pressure of the engine prevailing in the air intake line also acts on the side of the diaphragm remote from the valve seat body. Such a pressure control valve has the disadvantage that the masses that must be moved by the diaphragm are still relatively great, so that the reaction speed in the event of pressure changes is still too slow.


The present invention provides formulations which greatly improve the physical and chemical stability of pesticides such as insect growth regulators, in liquid feeds, and liquid feed supplements. The present invention prevents or reduces stratification in liquid feeds and liquid feed supplements.

Liquid feeds and liquid feed supplements for economic and companion animals can be formulated to deliver a complete supplemental package for a full-range of diets. Such liquid feeds and liquid feed supplements can supply protein, mineral, additives and vitamin nutrition necessary to support desired performance levels. In general, these "liquid" products are suspensions of protein sources, and actually contain about 60–70% dry materials. However, no matter how well-balanced a diet, or how effective an additive, the feed offered must be eaten to be effective.
Ideally, a ration would reach every animal exactly as it was formulated, with each bite throughout the day representing the desired mix of ingredients and additives. In reality, feedstuffs can separate in the bunk, and animals may sort for preferred portions of the diet (i.e., grain), eating them first. If a pesticide were to be contained within the liquid feed, it would be important that it stay uniformly mixed throughout. Otherwise, undesired dosing could occur.
In view of the foregoing, there is a need in the art for economic and companion liquid feed and liquid feed supplement, which contains a pesticide, to remain uniformly mixed. A liquid feed which eliminates stratification in animal feed such as in a holding tank or a lick tank, is highly desirable. The present invention satisfies these and other needs.


A fuel cell includes a membrane-electrode assembly and a separator. The membrane-electrode assembly has an electrolyte and a pair of electrodes that are disposed on respective sides of the electrolyte. The membrane-electrode assembly and the separator are stacked in a stacking direction. A reaction surface of the membrane-electrode assembly is in a vertical direction along a direction of gravity and has a shape having a longer dimension in a horizontal direction. The fuel cell is provided with a reactant gas passage to allow a reactant gas to flow along a longitudinal direction of the reaction surface. The reactant gas is an oxidant gas or a fuel gas. A drain channel to allow product water from the reactant gas passage to be drained away is disposed between the membrane-electrode assembly and the separator and under the reaction surface in the direction of gravity.

1. Field of the Invention
The present invention relates to a fuel cell.
2. Discussion of the Background
For example, in a solid polymer electrolyte fuel cell, a membrane-electrode assembly (MEA) is sandwiched between a pair of separators, the membrane-electrode assembly including a polymer electrolyte membrane formed of a polymer ion exchange membrane, and the anode and cathode electrodes that are disposed on the respective sides of the polymer electrolyte membrane. In general, a plurality of fuel cells is stacked together to form a fuel cell stack, and in addition to stationary use, the fuel cell stack is incorporated into a fuel cell vehicle to be used as an in-vehicle fuel cell system.
The above-mentioned fuel cell is provided with a fuel gas passage for passing a fuel gas to the anode electrode (hereinafter, referred to as a reactant gas passage), and an oxidant gas passage for passing an oxidant gas to the cathode electrode (hereinafter, also referred to as a reactant gas passage), within the respective surfaces of the separators. In addition, a cooling medium passage for passing therethrough a cooling medium is provided in the longitudinal direction of the separators, for each power generation cell or for each set of a plurality of power generation cells.
In this type of fuel cell, in order to secure a favorable ionic conduction property, the electrolyte membrane needs to be maintained at a certain water content. For this reason, a system is employed, in which an oxidant gas (for example, air) and a fuel gas (for example, hydrogen gas) as reactant gases are humidified and supplied to the fuel cells.
When the reactant gases are humidified, water contained in the reaction gases used for the humidification may be liquefied without being absorbed in the electrolyte membrane, and may stay in the reactant gas passages. On the other hand, in the fuel cell, water is produced in the cathode electrode by the power generation reaction, while the product water diffuses back into the anode electrode via the electrolyte membrane. Consequently, at the lower end, in the direction of gravity, of the reactant gas passage, water content tends to condense and remain due to the effect of gravity, and thus flooding of the condensed water may occur.
As a fuel cell configured to efficiently drain product water while effectively discharging exhausted gas, there is known, for example, the solid polymer electrolyte fuel cell disclosed in Japanese Patent No. 3123992. As shown in FIG. 11, the fuel cell includes a frame 1. A cell 2 and a cathode-side passage substrate 3 are installed on one surface of the frame 1, while an anode-side passage substrate 4 is installed on the other surface of the frame 1.
The cell 2 includes a solid polymer electrolyte 2a which is sandwiched between a cathode 2b and an anode 2c. In the cathode-side passage substrate 3, a plurality of cathode-side passages 3a are formed, while in the anode-side passage substrate 4, a plurality of anode-side passages 4a are formed.
On the upstream side of the frame 1, there are formed a pair of water supply manifold holes 5a, a groove hole 5b through which the water supply manifold holes 5a communicate with the anode-side passages 4a, a pair of fuel gas supply manifold holes 6a, and a groove hole 6b through which the fuel gas supply manifold holes 6a communicate with the anode-side passages 4a. On the downstream side of the frame 1, there are formed a pair of fuel gas discharge manifold holes 7a, a groove hole 7b through which the fuel gas discharge manifold holes 7a communicate with the anode-side passages 4a, a pair of water discharge manifold holes 8a, and a groove hole 8b through which the water discharge manifold holes 8a communicate with the anode-side passages 4a.
Then unreacted fuel gas which has passed through the anode-side passages 4a is discharged from the groove hole 7b to the outside of the battery through the fuel gas discharge manifold holes 7a, while the water which has passed through the anode-side passages 4a is discharged from the groove hole 8b to the outside of the battery through the water discharge manifold holes 8a.


Apparatus for the selective palletization of articles, particularly boxes, having different characteristics, including an article bar code reader which controls an automatic transfer device for the selective transfer of the articles from a feeder conveyor to respective pallets arranged in respective processing stations for loading the pallets with articles and for removing the loaded pallets, in which the processing stations are aligned above respective segments of a conveyor for transferring empty pallets from an accumulation unit for a stack of unloaded pallets, and an elevator device for the unloaded pallets which is interposed between the exit conveyor and each processing station, which defines, together with the related segment of the conveyor and with the related elevator device, a processing module which is actuated in a substantially independent manner.

The present invention relates to an apparatus for the selective palletization of articles having different characteristics.
The present invention solves, in a simple and fully automatic manner, a problem which is common to many manufacturing industries and relates to the provision of a palletization apparatus which is able to remove articles having different characteristics, for example boxes, from a common feeder, of selecting said articles according to their characteristics, and of grouping together the articles which have common characteristics, i.e. that belong to a same type or "family", on pallets whose feeding to respective loading stations is performed s as to entail no substantial interruption of the production cycle.

Apparatus for the selective palletization of articles having different characteristics


An aircraft anti-icing system includes a source of high temperature gas, a housing, at least one conduit to carry the high temperature gas from the source to the housing, the at least one conduit coupled to the housing and the source, at least one nozzle coupled to the at least one conduit, at least one nozzle configured to impart a rotational motion to the high temperature gas before exhausting the high temperature gas into the housing, and a port for exhausting air from the housing.

The present invention relates to an improvement in anti-icing systems for aircraft jet engine propulsion systems.
The formation of ice on aircraft wings, propellers, air inlets of engines, etc. has been a problem since the earliest days of heavier-than-air flight. Any accumulated ice adds considerable weight, and changes the airfoil or inlet configuration making the aircraft much more difficult to fly and in some cases has caused loss of aircraft. In the case of jet aircraft, large pieces of ice breaking loose from the leading edge of an engine inlet housing can damage rotating turbine blades or other internal engine components and cause engine failure.
One of the most common anti-ice techniques has been the ducting of hot gases into a housing adjacent to the likely icing area. Current techniques to solve this problem generally fall into one of two types of systems: Impingement style ring systems or swirl nozzle systems. In each case, the hot gas conduits simply dump hot gases into a housing, such as the leading edge of a jet engine housing or a wing leading edge. While often useful, these systems are not fully effective due to the low quantity of hot gases introduced relative to the mass of air in the housing, the heating effect tending to be limited to the region near the hot gas introduction point, and the complexity of the hot gas duct system.
In impingement style ring systems, hot air is impinged on the metal lipskin by strategically positioned holes in an annulus shaped tube that runs 360 degrees around the front of the inlet. The air impinges on the internal lipskin surface and causes the metal temperature to increase and break off any ice accretion.
The existing swirl nozzles discharge the hot air through a few non-circular sub-nozzles that create a flow field. The air is discharged at a high velocity so that it creates a swirling effect in the forward most inlet compartment, commonly referred to as the D-duct. The air continues to move 360 degrees around the annular D-duct compartment. It circulates around the compartment several times until it exits into the ambient through an exhaust port. Since the inlet lipskin consists of most of the internal compartment surface area, the hot air heats the lipskin and causes any ice accretion to break loose. Although the figures and verbiage of the specification use nose cowl deicing for explanatory purposes, the invention disclosed herein may apply to any other housing subject to ice formation including, but not limited to, wing conduits and ducts.
Both systems have limitations. The impingement ring style anti-ice systems have a cumbersome tube and support structure that runs 360 degrees around the front inlet compartment. While these systems generally have very high heat transfer ratios they are also very heavy. Swirl nozzle systems are generally significantly lighter than impingement ring style systems and use less air to de-ice but suffer from lower heat transfer.

Method and apparatus for aircraft anti-icing


A hard bag cleaner door is disclosed having air directing rib vanes integral with its inner surface. These vanes take the form of, alternately, angled J-shaped ribs and short straight interleaved ribs. All the ribs are stepped so that the flow passage for air moving along the interior side of the bag door diverges as more bag air is introduced to it so that it directs efficiently air flow to a lower disposed motor-fan section of an adjoining hard bag portion.

1. Field of the Invention
This invention relates to floor care appliances and, more specifically, to an airflow arrangement for a hard bag cleaner.
2. Summary of the Prior Art
The use of hard bag cleaners with air directing internal ribs in their bag cavities is well known. But, with the advent of the entrance of more cleaners having a clean air system in the marketplace, effective, efficient direction of dirt collecting bag discharge air towards such a cleaner's motor fan system has become more critical. Accordingly, it would be advantageous to provide a cleaner having a clean air system with a ventilating arrangement which, downstream of the bag, minimized back pressures, eddy currents, noise and the like so that an efficient flow path could be established through the dirt bag cavity to provide a more effective vacuum cleaner suction air system.
It is, therefore, an object of this invention to aid in the provision of a lower energy loss airflow path from dirt bag discharge to the cleaner suction fan.
It is another object of the invention to provide a series of airflow directing vanes within a hard bag cavity to guide dirt bag discharge air.
It is a further object of the invention to provide airflow guide vanes on the internal side of a panel of a hard bag cleaner.
It is an additional object of the invention to provide these guide vanes of the bag door of the hard bag cleaner.
It is a still further object of the invention to provide an improved internally vaned hard bag panel and/or bag door.

Hard bag door with air directing arrangement


A shoe holder is disclosed, adapted to serve as display means in stores and more especially supermarkets, hypermarkets or specialized stores, with a view to facilitating sale of this type of article. The shoe holder comprises a central rod terminated by a hook for suspension and two lateral support elements on which the shoes are fitted. According to the invention, the shoes being joined by a supple tie of the fine steel cable or polyamide thread type, the shoe holder comprises means for connecting, via said tie, the central rod to the assembly constituted by the shoes and the supple tie. These so-called connection means are constituted in particular by at least one piece fast or integral with the central rod and comprising an opening whose periphery is closed and through which the supple tie passes. The invention mainly concerns shoe manufacturers and retailers and manufacturers of accessories made by injected plastic moulding.

In a supermarket, shoes are generally placed on shelves without being packaged and the customer chooses from the articles displayed. For current articles, they may even be selected directly from tubs where the goods are placed in bulk. This sales technique is not suitable for shoes since the customer must be able to examine the different styles offered for sale, then check that the style chosen is available in his/her size, find two matching shoes and, finally, try them on to make sure that they fit.
Due to the customers' lack of discipline, there is very rapidly disorder in the shelves and it is necessary to check, shoe by shoe, to find the sizes. To facilitate the search, it has become current to use a supple tie such as for example a fine steel cable or a polyamide thread to join the two shoes going together.
Furthermore, to facilitate storage of shoes, accessory manufacturers have developed shoe holders which enable the pair of shoes to be arranged by order of size on a bar fixed in the shelves. This type of shoe holder, described in particular in document GB-A-2 103 081, comprises a central rod terminated by a hook for suspension and two lateral support elements on which a pair of shoes may be fitted. The advantage is the saving of space since the shoes are disposed vertically; furthermore, the styles are largely displayed, which enhances the product in the eyes of the public and this helps the customer to make his/her choice.
Unfortunately, experience has shown that, when the customer has tried on a pair of shoes which does not suit him, he does not put it back on its shoe holder. Therefore, not only the shoes, but also the shoe holders are in disorder. Similarly, experience has shown that the shoe holders are abandoned in the aisles after the customer has taken the chosen shoes.
It is an object of the invention to propose a shoe holder which overcomes the drawbacks set forth hereinabove, in that it is fast with the pair of shoes that it supports, is difficult to disconnect therefrom, whilst allowing the shoes to be easily tried on.


A power unit operable to power equipment, the power unit including an electric motor, multiple removable and rechargeable battery packs, multiple switching elements, and a control unit. Each of the switching elements is connected between one of the battery packs and the electric motor and operate in one of an open position or a closed position. The control unit is operable to manage the position of the switching elements. The control unit is configured to determine whether one or more battery packs are supplying power for the electric motor, measure a voltage of each of the battery packs, determine whether each of the voltage measurements is within a predetermined value to each other, calculate a pulse width modulated (PWM) signal for each of the switching elements, assign each PWM signal to one of the switching elements, and apply each of the PWM signals to the assigned switching element.

Connecting multiple battery packs together can increase the capacity of the battery power supply system. For example, connecting multiple battery packs in parallel generally increases the capacity (amp-hours) of the battery power supply system while the combined output retains the voltage level of the individual battery packs. However, if the voltages of the battery packs, when connected in parallel, are not approximately equal, charging and discharging issues can arise.
One such issue for parallel-connected battery packs is referred to as cross charging. Cross charging can occur when one of the battery packs is at a higher voltage, or state of charge, than the state of charge of other parallel-connected battery packs. When this occurs, current from the battery pack at the highest state of charge will begin to charge the battery packs at lower voltages. This may reduce the cycle life of the battery packs or damage the battery packs during the undesired charging and discharging.
The present disclosure attempts to address this problem by providing a power unit that includes a control unit and switchable elements to control the discharging sequencing of the individual battery packs.

Power unit including multiple battery packs for use with outdoor power equipment


A method is described for producing silicon carbide particles using a silicon source material and a hydrocarbon. The method is efficient and is characterized by high yield. Finely divided silicon source material is contacted with hydrocarbon at a temperature of 400.degree. C. to 1000.degree. C. where the hydrocarbon pyrolyzes and coats the particles with carbon. The particles are then heated to 1100.degree. C. to 1600.degree. C. to cause a reaction between the ingredients to form silicon carbide of very small particle size. No grinding of silicon carbide is required to obtain small particles. The method may be carried out as a batch process or as a continuous process.

1. Field of the Invention
The present invention relates, generally, to methods for producing silicon carbide and, more particularly, to methods for producing silicon carbide having small particle size. Specifically, the present invention relates to improved methods which are more efficient than previously available for producing silicon carbide particles of very small diameter.
2. Description of the Prior Art
Silicon carbide is an abrasive material which is widely used in a variety of grinding and polishing applications. Its hardness is 9.5 on the Mohs scale and, therefore, is only slightly less than the hardness of diamond (which is 10 on the same scale).
Silicon carbide is conventionally made by reacting silica particles with carbon particles at 1800-2000.degree. C. The chemical reaction for the process (known as the Acheson process ) is: EQU SiO.sub.2 +3C.fwdarw.SiC+2CO
Silicon carbide was first made by this reaction in 1891 in an electric arc furnace. High temperature is required for this reaction because the silica and carbon are contained in separate particles. At 1800.degree. C., silica vaporizes, allowing the two reactants to come in contact.
Another known process involves the reaction of elemental silicon and carbon particles at 1100.degree. C. to make silicon carbide, as follows: EQU Si+C.fwdarw.SiC
Silicon carbide can also be produced with reactions between silanes and a hydrocarbon: EQU SiH.sub.4 +CH.sub.4 .fwdarw.SiC+4H.sub.2 EQU SiCl.sub.4 +CH.sub.4 .fwdarw.SiC+4HCl
Because the Acheson process requires high temperature and a long reaction time, particle growth during the reaction is significant and results in a relatively large particle size distribution (greater than 1 micron) that is not sinterable. These particles must be ground to a smaller size before they can be sintered.
The other two processes discussed above proceed at lower temperatures than the Acheson process, and the reaction times are shorter so that a small particle size distribution (less than 1 micron) results that can be sintered directly. The cost of the silicon sources (i.e., silicon and silane) for these two processes, however, are expensive as compared to the cost of silica, thereby resulting in an expensive silicon carbide product.
Today silicon carbide powders are produced in various grades. The differences between the high and low grades are purity and particle size. Low grade silicon carbide consists of relatively low purity (less than 98%) particles having a diameter of 0.1-10 millimeters. High grade silicon carbide consists of high purity particles (greater than 98%) having a diameter of 0.5 to 5 microns. Low grade silicon carbide is widely used as an abrasive in polishing and grinding wheels.
Because of its high melting point (2200.degree. C.), silicon carbide is also used as refractory in high temperature furnaces. High grade silicon carbide is also sintered to make various types of components, such as fittings, feed throughs, etc. for high temperature applications.
Conventional manufacturing methods for producing silicon carbide utilize electric-resistance furnaces to provide the thermal energy which is necessary to produce the material. Such methods use a significant amount of energy. A solar energy furnace has also been used.
The costs associated with handling large quantities of electricity, and the costs associated with crushing the silicon carbide to smaller particles, account for the major costs in producing the material using conventional techniques.
U.S. Pat. No. 4,419,336 (Kuriakose) describes an improved electric resistance furnace for producing silicon carbide. U.S. Pat. No. 4,534,948 (Baney) describes a process for producing silicon carbide using specific polysilane polymers as starting materials. The polymer is heated to 1600.degree. C. in an inert atmosphere to form silicon carbide. The main advantage of this approach is that the polymer can be pre-formed into fibers or other shapes which the silicon carbide assumes when it forms. These patents do not describe a process for forming silicon carbide of very small particle size.
U.S. Pat. Nos. 4,162,167; 4,789,536; 4,904,622; and 5,021,230 describe manufacture of silicon carbide particles using silica particles and carbon particles which are mixed and then heated to a very high temperature.
U.S. Pat. No. 4,327,066 describes the manufacture of silicon carbide particles by heating silica particles in an atmosphere of hydrocarbon gas and hydrogen gas in a one-step process.
Japanese Patent Application No. 61-6109 describes a process for forming silicon carbide by reducing silica by means of a hydrocarbon at 1300.degree. -1500.degree. C. The silica must be heated to this temperature range before the non-heated hydrocarbon gas is introduced. The hydrocarbon gas cannot be pre-heated or else it is said to decompose before reacting with the silica.
Japanese Patent Application No. 61-6113 describes a process for manufacturing metallic silicon. Silica powder is reacted with a hydrocarbon at a temperature of at least 1300.degree. C. such that part of the silica powder is reduced and converted into silicon carbide. Then silica powder and silicon carbide are charged into a furnace at a temperature of at least 1800.degree. C. to produce metallic silicon.
At the temperatures involved in the one-step process of U.S. Pat. No. 4,327,066 and the foregoing Japanese applications, the rate of pyrolysis of the hydrocarbon is so fast that the carbon will not coat the silica but will form its own distinct particles. This results in distinct silica and carbon particles (similar to the conventional Acheson process). If the carbon does not coat the silica particles, the silica will vaporize as silicon monoxide at the high temperature involved in the process described in the aforementioned U.S. patent and Japanese applications. As a result, there are low product yields.
U.S. Pat. No. 4,869,886 describes a process for producing high density silicon carbide sinters. Particulate silicon is produced by introducing a. silicon compound to a first reaction zone at a temperature higher than the melting point of silicon to form fused spherical silicon particles. These particles are then reacted with a carbon compound at a lower temperature to produce silicon carbide.
U.S. Pat. No. 4,900,531 describes a process in which a silicon-containing precursor gas is heated to yield molten silicon which can then react with carbon walls of the reactor to produce silicon carbide. The resulting product is not a powder.
U.S. Pat. No. 5,082,872 describes a process for producing ceramic materials by pyrolysis of preceramic polysilanes by rendering the polysilanes infusible prior to pyrolysis by exposure to UV radiation in the presence of a reactive gas.
U.S. Pat. No.5,093,039 describes a process for producing electrically conductive sintered silicon carbide by mixing two sizes of silicon carbide particles and then heating the mixture. The small silicon carbide particles are produced by reacting a silicon halide and a hydrocarbon.
There has not heretofore been provided a process for producing silicon carbide particles of small particle size in an efficient manner with high yields.

Method for silicon carbide production by reacting silica with hydrocarbon gas


The invention refers to an amplifier (1) comprising a switchable capacitive divider (10) for dividing a supply voltage delivered to the amplifier (1), the switchable capacitive divider being coupled to a coupling circuit (15) via a first wire and a second wire, the coupling circuit determining a connection path between said first and second wire and a first capacitor (C2) and a switchable power circuit (20).

Class D amplifiers comprise a switching power stage for driving a load. The output signal is a pulse-width modulated (PWM) signal. The output signal is further low-pass filtered at the amplified output and the remaining signal is the analog output signal. A multi-level PWM signal, which represent more accurately the input signal may be used, for reducing the high frequency content, and simplify filtering. For such an amplifier, an output stage that can reproduce multiple output levels may be used. FIG. 1, shows a common way to implement a multi-level switching power-stage, that operates from a single supply voltage. It is implemented by putting multiple half-bridge switching stages in parallel i.e. combinations M1, M3 and Mx, My in FIG. 1. When the parallel stages are driven by appropriate signals and the outputs are summed up, a multi-level PWM output is generated. A three-level switching power stage using this principle is shown in FIG. 1. Z1 and Z2 are inductors, for making an accurate superposition of the output signals from the parallel half-bridge stages.
The three-level switching stage shown in FIG. 1 may generate an output signal with a level equal to ground, half supply voltage Vs or supply voltage Vs. A known circuit for deriving a voltage that equals half of the supply voltage is a capacitive divider as shown in FIG. 2 and also in Bekhout, Marco "Integrated Audio Amplifiers in BCD Technology", Kluwer Academic Publishers, 1997. If an output voltage V0 is larger then half the supply. Capacitor C2 will be discharged by the load current I1 and the voltage across the capacitor will decrease and hence the output voltage Vo. Capacitor C1 is charged by the load current I1 and the voltage across this capacitor will increase. When the output voltage drops a certain value below half the supply voltage the capacitors are interchanged. The capacitor C1 connected between nodes a and b before interchanging will be connected between nodes c and d afterwards with the positive plate of the capacitor connected to node c. Capacitor C2 connected between nodes c and d will after interchanging be connected between nodes a and b with the positive plate of the capacitor connected to node a. After the interchanging the output voltage is again above half the supply voltage. By repeating the interchanging of the capacitors continuously a voltage equal to half the supply voltage with some ripple is generated.
The circuit also works if only one capacitor is and it is switched as was the case for the situation with two capacitors. During switching the output voltage is not defined. A buffer capacitor can be added to supply the current to the load during switching. Because of the series-parallel connection of C1 and Cb there will be some charge redistribution and the steady-state output will be somewhat lower then half the supply voltage as is shown in FIG. 3. The implementation of this capacitive divider stage is less complex than that shown in FIG. 2 and requires fewer transistors.


Maintaining a reliable link includes altering a record of information transmitted across a network from a mobile unit to a destination based on an acknowledgment by the destination of receipt of the transmitted information and transmitting information from the mobile unit to the destination based on the record after the mobile unit establishes a new interface connection to the destination.

This invention relates to maintaining a reliable link.
Mobile nodes include devices such as laptop and portable computers, personal digital assistants, telephones, and other wireless or personal devices may be capable of connecting to a network from varied locations. To connect to an Internet Protocol (IP) based network, for example, a mobile node just needs to be attached to a network to establish a network presence that allows information to be sent between the mobile node and arbitrary points in the IP network.
Referring to FIG. 1, for example, a mobile node 100 can wirelessly and continuously be connected to a network infrastructure 102 using the same IP address regardless of the mobile node's physical location. The mobile node 100 is identified by a home address associated with the mobile node's home network 104. When the mobile node 100 connects to the network infrastructure 102 away from its home link 106, the mobile node 100 is identified by the home address and by at least one care-of address providing information about the mobile node's current location.
Information sent across the network infrastructure 102 to the mobile node's home address is transparently routed to the mobile node's care-of address. The information destined for the mobile node's home address is received at the home link 106 by a home gateway or router 108 that tunnels the information to the mobile node's care-of address via an IP tunnel 110. The care-of address may be an address for a foreign gateway or router 112 that forwards the information to the mobile node 100 over a foreign link 114 that may or may not use IP routing.
As the mobile node 100 changes its physical location and switches to a different foreign gateway or router to maintain connectivity to the network infrastructure 102, the mobile node 100 updates the home gateway or router 108 with its new care-of address. In this way, the mobile node 100 can relocate, connect to various foreign gateways or routers, and maintain a constant IP address presence without interruptions or disturbances in network connectivity. In switching between foreign gateways or routers, however, information may be lost in transit from the mobile node 100 to the home network 104.


A combined illuminating magnifier and flashlight has a housing with a pivot, a frame for carrying a magnifying lens mounted to the housing and being rotatable about the pivot between a retracted position, where the magnifying lens is located in the housing and an extended position where the magnifying lens is available for use. A light is mounted in the frame for illuminating the magnifying lens. The light, when the frame is retracted, is aligned with a flashlight lens such that the device can function as either an illuminating magnifier or as a flashlight.

A retractable illuminating magnifier which provides compactness and ease in operation is described in U.S. Pat. No. 5,754,349. That device utilizes, among other features, a conductive spring to simplify construction.
In U.S. Pat. Nos. 2,297,232 and 1,900,930, circular magnifying devices are shown which are extendable, but these have no illumination.
In U.S. Pat. No. 1,884,968, a combined flashlight with reading glass is shown.
These devices all have various shortcomings. In particular, it has been difficult to achieve a multifunctional device which still minimizes size, is easy to use yet provides not only magnification or illuminated magnification but can function as an effective flashlight.

Retractable lighted magnifier and flashlight


A water-disintegrable cleaning sheet comprising a web of water-dispersible fibers having incorporated thereinto a water-soluble binder having a carboxyl group; at least one metallic ion selected from the group consisting of ions of alkaline earth metals, manganese, zinc, cobalt, and nickel; and an aqueous cleaning agent containing an organic solvent, is disclosed. The sheet satisfies both water disintegrability and strength even when cotained a cleaning agent of high water content.

Water-disintegratable papers or cleaning goods made of a chemical-containing water-disintegratable paper which can be thrown into water have been used as toilet paper or for cleaning a toilet room or toilet equipment. Conventional water-disintegratable paper usually contains a dry strength agent such as polyvinyl alcohol, carboxymethyl cellulose, and cationic starch, for enhancing dry paper strength without impairing water disintegrability.
However, a paper sheet containing a dry strength agent undergoes serious reduction of strength when impregnated with water. Therefore, where a water-disintegratable paper is combined with a cleaning agent for cleaning or sterilization of floors, walls, furniture, and toilet equipment or for use as toilet paper, the cleaning agent to be combined therewith has been limited to liquid substances or chemicals having no or very low water content.
In using a cleaning agent of high water content, it has been necessary that the cleaning agent should be foamed and sprayed on a water-disintegratable paper immediately before use and be used without delay in order to suppress water absorption into paper and to prevent strength reduction.
Polyacrylamide or the like, as a dry strength agent endows paper with strength enough to withstand use even with a small amount of water being impregnated in the paper sheet, but tends to impair water disintegratability of the sheet.
Hence, the conventional dry strength agents could not provide a strength enough to withstand cleaning use even when combined with a cleaning agent of high water content in good balance with water disintegratability.
It has been proposed to spray a binder solution containing polyvinyl alcohol and borax on a paper sheet followed by drying by heat whereby polyvinyl alcohol and borax are reacted to provide water-disintegratable paper having temporary water resistance, which is useful as absorbent materials such as napkin or diaper, as disclosed in JP-A-47-9486 (the term "JP-A" as used herein means an "unexamined published Japanese patent application"). Further, JP-A-61-296159 discloses a water-disintegratable paper in which an aqueous solution containing salts such as potassium salt, calcium salt and barium salt, is impregnated into a fibrous sheet containing carrageenan as a binder, which is used for a wetting tissue paper. Furthermore, JP-A-55-103393 discloses a method for preparing a paper having high strength in a dry state while low in wet state, which comprises treating paper surface with alkali metal and/or alkali earth metal salt of polyacrylic acid polymers, and that the paper can be used for writing paper, printing paper, wrapping paper, etc. These water-disintegratable papers, however, do not withstand the mechanical force in cleaning work when impregnated with water.


An electronic method for matching a user with a golf ball includes playing a first digital audio file to a user via a computer and playing a second digital audio file to the user via the computer. Each of the first digital audio file and the second digital audio file correspond to an acoustic response of a respective golf ball to a standardized impact force. The method then includes receiving an input from the user via the computer, where the input corresponds to a preferred acoustic response selected from the acoustic response of the first golf ball and the acoustic response of the second golf ball. Once the preferred response is determined, the method includes displaying a golf ball model that corresponds to the preferred acoustic response.

Golf balls are manufactured using a variety of processes and materials. The response of the ball when struck by a club may vary as a function of the hardness of the materials chosen. For example, a harder ball will typically travel further when struck by a driver than a softer ball. Likewise, a softer ball will typically spin more when struck by a wedge than a harder ball. Using these generalizations, many golfers will select a ball according to their preference for distance or spin control. These attributes are often referenced on golf ball packaging and advertising.
In addition to distance and spin control, however, many golfers also want a ball that has an expected "feel." Feel is generally a subjective assessment of the response of the ball when struck by a club, though it is largely influenced by the sound of the impact. While the acoustic response of the ball may be an important factor in ball selection to some golfers, it is typically not considered or referenced in current retail practices.

Fitting golf balls using acoustic response


An apparatus for the manual sharpening of blades of cutting tools, includes at least two sharpening elements each with at least one sharpening edge, wherein the sharpening elements can be disposed to be partially overlapping, and partially in contact with each other, such that in a first state, one sharpening edge of each of the first and the second sharpening elements defines a first and a second currently used sharpening edge, respectively, and these sharpening edges cross one another at a crossing point and form a V-shaped gap with an angle, into which the cutting tool blade is inserted. The first and second sharpening elements can be shifted with respect to each other while maintaining the angle, such that the crossing point is shifted along the first and/or second currently used sharpening edge, and the at least positionings of the sharpening elements with respect to one another are reversibly fixed.

1. Field of the Invention
This invention relates to an apparatus for manually sharpening the blades of cutting tools, in particular, knives or scissors.
2. Description of Related Art
Various forms of apparatuses having two sharpening elements allowing both sides of a blade to be processed, and thereby sharpened, simultaneously, are already known.
For instance, the patents DE 202 03 955 U1 and U.S. Pat. No. 4,599,919 provide for a sharpening apparatus in which two crossed sharpening elements (plates of hard metal) form a V-shaped gap for sharpening. The processing angle formed by the V-shaped gap in these cases is permanently predetermined. The hard-metal plates in DE 202 03 955 U1 have a basic rectangular shape, whereas in U.S. Pat. No. 4,599,919 the basic shape of the sharpening elements includes a triangular tip at one end. In both of these documents the two sharpening elements of the apparatus have the same shape as one another, each with two sharpening edges. This configuration makes it possible to exchange the sharpening elements for one another so as to employ the other sharpening edge of each of them, which increases the working life if the sharpening elements.
A disadvantageous feature of these constructions, however, is that the sharpening process always occurs at the same place on whichever sharpening edges are operative, so that this site rapidly becomes worn down. According to DE 202 03 955 U1, all that can be done is to make a second edge site usable by rotating the sharpening elements through 180° and exchanging their positions.
It is known from U.S. Pat. Nos. 562,223, 584,933 and 6,393,946 B1 to dispose the sharpening elements so that they can be rotated about an axis and fixed in selected positions within the sharpening apparatus. By appropriate choice or adjustment of the rotational position of the sharpening elements, the sharpening edges can be set at the desired angle for processing the blades. In this arrangement, a different site on the sharpening edges is used for sharpening, depending on the selected angle. For a given angle, however, it is always the same edge site that is used, and since in practice such an apparatus is often used repeatedly for blades of the same kind, rapid wear results. To prolong the working life, these documents disclose only that each of the sharpening elements comprises several sharpening edges, which can be employed in succession by appropriate repositioning of the cutting element.
The patent GB 505,871 furthermore, discloses a sharpening apparatus in which the operative site on each sharpening edge depends on the pressure with which the knife to be sharpened presses against the edge, and on the opposing force generated when the user presses the parts of a handle together. Here it is disadvantageous that the relative position of the two sharpening elements cannot be fixed, so that the effective sharpening region varies continuously and is determined only at random.
Accordingly, a sharpening apparatus which overcomes these disadvantages, is desired.

Apparatus for manual sharpening of the blades of cutting tools


A lens driving apparatus and a lens driving method are capable of quickly and precisely setting the position of a lens to a predetermined position, if the resolving power of the amount of lens moving according to drive pulses is not even in the lens driving apparatus. A count pulse signal detection unit detects a count pulse signal CP in accordance with a rotation of a manual focus (MF) ring. A lens driving control unit outputs a drive pulse MP for moving a focus lens in correspondence with the detected count pulse signal CP to a lens driving unit. The lens driving control unit performs a control so that: the number of the drive pulses MP for a count period T differs between a time period within an initial count detection time period for the detected count pulse signal CP and a time period after the initial count signal detection time period; and the number of pulses for the former period is minimum and the number of pulses for the latter period is larger than the minimum number.

1. Field of the Invention
The present invention relates to a lens driving apparatus and a lens driving method configured to drive a lens by operating a rotation operation member that is not mechanically coupled to the lens.
2. Description of Related Art
A conventional method relates to a lens driving apparatus configured to drive a lens, such as a focus lens and a zoom lens built in a camera lens barrel. The lens driving apparatus is configured to output a rotation signal when a rotation operation member not mechanically coupled to the lens, such as a focus operation ring or a zoom operation ring, is operated and to drive the lens by means of an actuator including a motor mechanism, and the like, based on the rotation signal. Japanese Patent Application Laid-Open No. 01-161325 discusses a lens driving apparatus including a pulse generation unit configured to generate a pulse signal when an operation member is manually operated; and a motor driving control unit configured to drive a focus lens according to the generated pulse signal. In addition, Japanese Patent Application Laid-Open No. 01-161325 includes units configured to detect an amount and a speed of an operation of the operation member, respectively. By controlling the motor driving control unit according to the detected operation amount and the detected operation speed, the lens can be quickly driven, and by a large amount, when the operation member is quickly operated, whereas the lens can be driven slowly, and by a small amount, when the operation member is slowly operated. Thus, Japanese Patent Application Laid-Open No. 01-161325 can implement a lens driving apparatus that is very easy to operate. Similarly, Japanese Patent Application Laid-Open No. 06-242361 discusses a lens driving apparatus including a pulse generation unit configured to generate a pulse signal when an operation member is manually operated, and a lens driving mechanism configured to drive a lens according to the pulse signal. In Japanese Patent Application Laid-Open No. 06-242361, a lens driving control is performed by using the speed of operation of the operation member as one parameter and with reference to the other parameters such as the operation amount, the focal length, the subject distance, and the like to reduce difficulty in operating the operation member.
In both Japanese Patent Application Laid-Open No. 01-161325 and Japanese Patent Application Laid-Open No. 06-242361, the lens driving control is carried out according to the speed and the amount of an operation of the operation member. However, these conventional apparatuses do not consider the resolving power for the lens driving amount. Accordingly, these conventional apparatuses do not satisfy the speed and the precision required in setting the lens to a predetermined position. More specifically, FIG. 8 shows an example of the resolving power for the focus lens built in a lens barrel of a camera. The axis of the abscissa denotes a lens position of a focus lens FL with respect to an image sensor (charge-coupled device (CCD)) and the axis of the ordinate denotes a subject distance (corresponding to the lens in-focus position). A focus lens driving apparatus includes a stepping motor that rotates stepwise according to a drive pulse. Therefore, the lens position denoted on the axis of the abscissa corresponds to the number of drive pulses to be supplied to a stepping motor for driving the lens. The axis of the ordinate denotes the short distance side in its lower part and the long distance side in its upper part.
As can be understood from FIG. 8, the number of drive pulses with respect to variation of the in-focus position is large on the short distance side of the focus lens FL, whereas the number of drive pulses is small on the long distance side. The above-mentioned resolving power can be also referred to as the amount of variation of the in-focus position with respect to one drive pulse. It is understood that the resolving power is uneven in relation to the variation of the in-focus position. Accordingly, because the variation of the in-focus position occurring according to one drive pulse is small (i.e., because the resolving power is fine (high)) on the short distance side of the focus lens, focusing can be precisely performed. However, in changing the in-focus position by a large amount, it becomes difficult to perform quick focusing because a large number of pulses are required. On the other hand, on the long distance side, the variation of the in-focus position occurring according to one drive pulse is great (i.e., the resolving power is low). Accordingly, the focusing can be quickly performed when the in-focus position is changed by a large amount. However, it becomes difficult to perform precise focusing. In both Japanese Patent Application Laid-Open No. 01-161325 and Japanese Patent Application Laid-Open No. 06-242361, the lens driving speed and the lens driving amount are merely controlled according to the speed of an operation of the operation member. Accordingly, the control of the driving speed and the driving amount cannot be performed following the variation of the in-focus position. Therefore, in these conventional apparatuses, it is difficult to satisfy both the speed and the precision required in focusing on both the short distance side and the long distance side described above at the same time. The problem of speed and precision occurring in setting the lens position, caused due to uneven resolving power with respect to the lens drive amount, may arise not only in the case of a focus lens but also in a case of a zoom lens, where the lens driving is performed between the telephoto end and the wide-angle end.
The purpose of the present invention is to provide a lens driving apparatus and a lens driving method capable of quickly and precisely setting a lens to a predetermined position in a lens driving apparatus in which the resolving power of lens moving amount according to a drive pulse is uneven.

Lens driving apparatus and lens driving method


Some of the embodiments of the present disclosure provide a method for operating a testing system to test a device, wherein the testing system comprises a pressing module, the method comprising attaching the device to the pressing module of the testing system; while the testing system operates in a first mode of testing, pressing the pressing module to a first position such that (i) the device is electrically coupled to a first component via a first pin, and (ii) the device is electrically isolated from a second component via a second pin; and while the testing system operates in a second mode of testing, pressing the pressing module to a second position such that (i) the device is electrically isolated from first component via the first pin, and (ii) the device is electrically coupled to the second component via the second pin.

In various computing systems, a device may need to be coupled to a first component during a first time period, and to be coupled to a second component during a second time period. For example, during a first mode of testing a device, the device has to be coupled to a test engine. During a second mode of testing the device, the device has to be coupled to a memory (or to another test engine). An electro-mechanical relay can be used to selectively couple the device to either the test engine or the memory, based on the mode of the test. In a typical test environment, a large number of electro-mechanical relays can be used. However, such electro-mechanical relays usually consume large amount of space, and generally cannot be densely arranged in a test environment.

Pressure activated high density switch array


A method of demodulating a square root for processing digital signals is disclosed. The demodulation includes the following steps. First, define |l arg e| to be the larger one between the absolute value of two input values I and Q and define |small| to be the smaller one between the absolute value of the two input values I and Q. Next, define a first determining form by the inequalities 16|small≦16|l arg e|≦18|small| and 16|l arg e|=16|small|. In addition, define a second determining form by the inequalities 16|small|≦16|l arg e|≦18|small| and 16|l arg e|≠|small|. When the relation between |l arg e| and |small| conforms to the first determining form, the approximate root-mean-square value of the two input values I and Q is |l arg e|+2−5|l arg e|. When the relation between |l arg e| and |small| conforms to the second determining form, the approximate root-mean-square value of the two input values I and Q is |l arg e|+2−6|l arg e|.

1. Field of the Invention
The present invention relates to a method and apparatus for demodulating a square root. More particularly, the present invention relates to a method and apparatus used by a digital system or a signal communication system for demodulating a square root.
2. Description of the Related Art
In a very large scale integrated circuit (VLSI) digital system or a signal communication system, two input signals I and Q are often modulated into √{square root over (I2+Q2)}. In other words, the input values I and Q are combined to form a square root of the sum of squares. To obtain an accurate value of the square root, lots of hardware is required. Moreover, the performance of hardware is usually poor and the processing time is usually long. Hence, hardware circuits are not too suitable for the real-time computation of square roots. To resolve this problem, methods and apparatus for finding an approximate solution such as the coordinate rotation digital computer (CORDIC), the angular cone approximate wave envelop inspection method and circuits and so on have been developed.
In Taiwan Patent No. 480.415, a square root demodulation apparatus is disclosed. In the invention, a coordinate slicing theory is utilized to obtain an approximate square root of two input signals I and Q. Although the patent is capable of resolving the aforementioned problems, too many comparators must be used to obtain the solution. Therefore, the required integrated circuit is large and its production cost is high.
FIG. 1 is a table listing the relation between angle and error ratio for the aforementioned Taiwan Patent No. 480.415. As shown in FIG. 1, the error ratios within some range of phase angles (the ones inside the circles) for the input signals I and Q are large. For example, the error ration when the angle is 76° is as high as 3.00303%. This error ratio is quire significant in a communication system or other digital computation system having a narrow tolerance for errors.

Method and apparatus of demodulating square root for processing digital signals

Chung Shan Institute of Science and Technology, Armaments Bureau, M.N.D.


The present invention relates to methods, systems, and apparatus for inducing fractures in a subterranean formation and more particularly to methods and apparatus to place a first fracture with a first orientation in a formation followed by a second fracture with a second angular orientation in the formation. The first and second fractures are initiated at about a fracturing location. The initiation of the first fracture is characterized by a first orientation line. The first fracture temporarily alters a stress field in the subterranean formation. The initiation of the second fracture is characterized by a second orientation line. The first orientation line and the second orientation line have an angular disposition to each other.

The present invention relates generally to methods for inducing fractures in a subterranean formation and more particularly to methods to place a first fracture with a first orientation in a formation followed by a second fracture with a second angular orientation in the formation according to a time determination.
Oil and gas wells often produce hydrocarbons from subterranean formations. Occasionally, it is desired to add additional fractures to an already-fractured subterranean formation. For example, additional fracturing may be desired for a previously producing well that has been damaged due to factors such as fine migration. Although the existing fracture may still exist, it is no longer effective, or less effective. In such a situation, stress caused by the first fracture continues to exist, but it would not significantly contribute to production. In another example, multiple fractures may be desired to increase reservoir production. This scenario may also be used to improve sweep efficiency for enhanced recovery wells such as water flooding steam injection, etc. In yet another example, additional fractures may be created to inject with drill cuttings.
Conventional methods for initiating additional fractures typically induce the additional fractures with near-identical angular orientation to previous fractures. While such methods increase the number of locations for drainage into the wellbore, they may not introduce new directions for hydrocarbons to flow into the wellbore. Conventional method may also not account for, or even more so, utilize, stress alterations around existing fractures when inducing new fractures.
Thus, a need exists for an improved method for initiating multiple fractures in a wellbore, where the method accounts for tangential forces around a wellbore and the timing of inducing a subsequent fracture.

Methods for maximizing second fracture length


A reinforcing strip is applied to sheets by longitudinally advancing a leading sheet while the strip is adhered to it along a travel path to a downstream stop station and thereby drawing the strip from a supply and extending it longitudinally through an upstream stop station while simultaneously adhering the strip to the full length of the leading sheet. Then the leading sheet is arrested in the downstream stop station while a trailing sheet upstream of the arrested leading sheet is advanced downstream until a leading edge of the trailing sheet engages an upstream stop in the upstream station immediately upstream of a trailing edge of the leading sheet. The trailing sheet is then arrested with its leading edge engaging the upstream stop which it pushes downstream against the upstream edge of the leading sheet. Generally simultaneously the strip is adhered upstream of the upstream stop to the trailing sheet and the strip is severed at the upstream stop between the leading and trailing sheets. The leading sheet is then advanced longitudinally away from the upstream stop and the upstream stop is moved out of the path to longitudinally advance the trailing sheet downstream while the strip is adhered to it to the downstream stop station while drawing the strip from the supply and extending the strip through the upstream stop station. The cycle is repeated with the trailing sheet taking the place of the leading sheet and with another sheet following the trailing sheet and taking its place.

It is common practice in the paper art to reinforce of the edge of a sheet subjected to considerable use or stress by applying a segment of a reinforcing film to the edge. A good example of such apparatus is disclosed in U.S. Pat. No. 4,698,114.
A serious limitation of this apparatus as well as with other similar apparatuses stems from the fact that separate standard sheets vary in length. As a result, the sequence of operations is frequently disturbed and the reinforced sheets are delivered with cut edges or with severed reinforcing-film segments having lengths greater than the sheets they are adhered to. Recalibrating the known machines for use with sheets of a different length is an onerous task involving resetting various cams, timers, stops, and the like.
Another disadvantage of the known machines is that the rely on complex timing and control equipment. Thus if a sheet jams the machine may continue to operate, spoiling numerous work-pieces and jamming itself with material. Alternately if there is a sheet misfeed and a sheet is not fed, the machine may shut down, waiting for an operator to fix the problem, if necessary, and restart it.