Abstract: A semiconductor device according to the invention has a channel layer, which is sandwiched by a first and a second barrier layers, and an electron supply layer for supplying the channel layer with electrons through at least one of the barrier layers. The channel layer has a superlattice structure formed by periodically repeating, in the direction of electron movement, a first and a second semiconductor material regions, each of which has a different band gap from the other. With this superlattice structure, a plurality of mini-bands are formed within a potential well, which is formed by the first and second barrier layers. Impurity concentration of the electron supply layer is so controlled that electrons may move mainly within a mini-band in which effective mass of electrons is minimum among those mini-bands. Thus, a semiconductor device having a high electron mobility in the room temperature can be obtained without requiring high purification of crystal.

Abstract: A method of monitoring abnormality of a clock driver in an electronic apparatus having a clock supply unit that supplies a clock signal and a plurality of function executing units to which the clock signal is inputted for executing prescribed functions at an identical clock, wherein each function executing unit is provided with a clock driver which, on the basis of the clock signal, oscillates internally to reproduce a clock signal, includes monitoring cut-off of an input clock signal and cut-off of an output clock signal of the clock driver, and outputting an alarm upon judging that the clock driver is abnormal in a case where the output clock signal has been cut off but the input clock signal has not.

Abstract: When an object of treatment is subjected to, for example, a gas treatment in an airtight chamber, reaction products adhere to the inner wall surface of the chamber, an object holder therein, and the corner portions of the chamber. When a cleaning medium is injected into the chamber, according to the present invention, the reaction products are dissolved in the cleaning medium by hydrolysis. Thereafter, the cleaning medium is discharged from the chamber. Then, the chamber is heated and evacuated, so that water vapor is discharged to provide a predetermined degree of vacuum, whereupon the treatment can be started anew. Therefore, a wiping operation can be omitted. Moreover, the reaction products remaining at the corner portions of the chamber can be removed without forming a source of polluted particles, so that the necessity of overhauling can be obviated. Thus, fully automatic cleaning, so to speak, can be effected, and the chamber need not be open to the atmosphere, so that the throughput can be improved.

Abstract: A mobile telephone apparatus connects a portable telephone terminal to a vehicle-mounted booster device and performs communication via a vehicle-mounted antenna. The apparatus includes means for detecting that the portable telephone terminal has been connected to the vehicle-mounted booster device, means for decreasing transmitting power of the portable telephone terminal to fixed level when the portable telephone terminal has been connected to the vehicle-mounted booster device, and means for performing control so as to vary the transmitting power of the booster device when the portable telephone terminal has been connected to the vehicle-mounted booster device.

Abstract: A first terminal unit is connected to a line switch via a set of data lines. A second terminal unit is connected to the first terminal unit via a set of data lines. A third terminal unit is connected to the second terminal unit via a set of data lines. Therefore, the terminals are sequentially connected in series. Cells transmitted to the terminals are multiplexed by each terminal and sequentially transmitted upstream, to the third terminal unit, the second terminal unit, and the first terminal unit together with a token. Since the first terminal unit receives a first identification signal from a switch and a second identification signal from downstream, the first terminal unit recognizes that it is the highest order terminal unit, and sends a cell to the switch after separating the cell from a token which is to be returned downstream.

Abstract: A system for and a method of recognizing and tracking a target mark with a video camera is disclosed. The system includes a target mark (10) disposed on an object (1) and composed of a black circle and a white triangle mounted centrally on the black circle and three-dimensionally shifted from the black circle, a video camera (20) for imaging the target mark (10), a robot (30) supporting the video camera (20) and movable in directions with six degrees of freedom, an image processor (40) for processing image data of the target mark which is produced by the video camera (20), a shift calculating unit (50) for detecting a shift of the target mark (10) from projected histogram information of the target mark (10) which is produced by the image processor (40), and a robot controller (60) for controlling movement of the robot depending on the shift to enable the video camera (20) to track the target mark (10). The system is capable of tracking the target mark ( 20) attached to the object (1) on a real-time basis.

Abstract: A FIFO memory device includes a storage device and an address translator. The storage device contains a plurality of FIFO storage units cells connected in parallel, wherein data is input to and output from each of the FIFO storage unit cells one word at a time, and data is input to the storage device one word at a time and output from the storage device in units of a plurality of words. The address translator is disposed between a central processing unit and an input side of the storage device for translating an address specified by the central processing unit into an address specifying one of the storage unit cells of the storage device. The address translator includes a count enable signal output element responsive to addressing from the central processing unit for outputting a count enable signal, a counter responsive to the count enable signal from the count enable signal output element for counting up, and a selector responsive to a count value of the counter for selecting one of the storage unit cells.

Abstract: An apparatus for controlling the transportation speed of a sheet, such as a printed sheet or manuscript, includes a sheet transportation system and a speed controller. The transportation system includes a single drive motor and a plurality of rollers driven by the single motor and arranged in such a manner that a sheet to be transported is held by the rollers one after another. The speed controller includes a sensor for detecting the position of the sheet. The number of rollers which hold the sheet is determined. A speed controller provides the motor with a designated speed command calculated on the basis of the numbers of rollers, so that the actual sheet transportation speed is always constant regardless of the numbers of rollers which hold the sheet.

Abstract: The number of present updating data is detected from an updating bit map of a backup target medium. When it is equal to or larger than a reference value, a whole backup is executed. When it is smaller than the reference value, a differential backup is executed. After the backup was obtained, a copy coupling is executed and a merge process to reduce the number of media is performed. By eliminating the unnecessary media among the media which are used and by executing the successive reading or parallel reading from backup destination media, a decoding process to a recovery medium can be executed in a shortest time.

Abstract: A fault control system for a multi-processor system in which a plurality of processors are connected to each other via first and second communications buses, including a plurality of stations provided in the first communications bus and respectively connected to the processors. A supervisory station function unit, which is provided in each of the stations, supervises a state of the first communications bus. An ordinary station function unit, which is provided in each of the stations, establishes an interface between the processors and the first communications bus. One of the stations functions as a supervisory station in which only the supervisory station function unit is activated, and remaining stations respectively function as ordinary stations in which only the respective ordinary station function units are activated.

Abstract: An optical communication system transmits information with a pumping light beam acting as the carrier, and with a signal light beam. This optical communication system includes an optical fiber amplifier adapted to amplify the signal light beam by having the signal light beam and the pumping light beam propagate through a rare-earth-doped fiber doped with a rare-earth element. A modulating circuit modulates the pumping light beam with a high-frequency modulating signal having a period shorter than the life span of fluorescence resulting from an excited state. When the signal light beam and the pumping light beam are propagated in the same direction through the rare-earth-doped fiber, the transmission of information with the pumping light beam acting as the carrier, can provide transmission of a supervisory signal for an optical repeater.

Abstract: In a disk unit including a plurality of disk media of which any one surface is a servo surface and the other surfaces are all data surfaces; a servo head and data heads arranged on the servo surface and the data surfaces; a positioning mechanism for positioning the servo head and the data heads on desired tracks; and a control unit for controlling the positioning mechanism; the control unit reading servo data from the data surfaces and updates them to find offtrack compensated data, and the head positioning operation being controlled by using the offtrack compensated data and servo information on the servo surface, an offset occurring in the disk unit is compensated by setting the servo track center of the servo head as a reference for positioning the head; writing a pair of servo data for positioning the head onto said data surface while giving a predetermined offset amount which is offset from said track center; giving a predetermined offset amount to thus read and measure the pair of servo data and using t

Abstract: A non-volatile semiconductor memory device includes a semiconductor substrate with a first conductivity type, a first well of a second conductivity type formed on the semiconductor substrate, a second well of the first conductivity type formed on the first well, a plurality of memory cells provided in the second well and each including a tunneling insulation film having a thickness allowing a tunneling of carriers, a floating gate electrode provided on the tunneling insulation film, an interlayer insulation film provided on the floating gate electrode, a control electrode provided on the interlayer insulation film, and a pair of diffusion regions of the first conductivity type formed on the second well at both sides of a channel region.

Abstract: A thin film transistor (TFT) load type static random access memory (SRAM) which includes a memory capacitor in addition to the stray capacitance. The SRAM includes a semiconductor substrate and a memory cell provided on the semiconductor substrate. The memory cell includes first and second transfer transistors, first and second driver transistors, first and second thin film transistor loads and first and second memory capacitors. The first and second memory capacitors include a storage electrode, a dielectric layer which covers the storage electrode, and an opposing electrode formed on the dielectric layer. A connection region is provided in which the storage electrode of the first memory capacitor, the drain region of the second thin film transistor load and the gate electrode of the first driver transistor are connected.

Abstract: When amounts of processing of processes to be distributed are known, a scheduler in a client allots the processes in order of their respective amounts of processing to computers in ascending order respective of cumulative amounts of processing of the computer. The cumulative amount of processing in each computer is updated by adding the amount of processing of the allotted process to the cumulative amount of processing of the computer each time a process is allotted to a computer. Each computer supplies situation data such as usage, together with reliability thereof to a server which distributes computers, and the server allots usable computers to the client on the basis of these data. The agent of each usable computer supplies a resource use token to the client so as to permit exclusive use of a computer resource.

Abstract: On receiving voice data from a subscriber accommodated in a broadband network, a terminal adaptor separately puts the voice data in cells in 8-bit units every 125 .mu.s separately, and transmits the cells by a remote switching unit in the broadband network to subscriber terminal equipment. The subscriber terminal equipment accommodates and processes each item of 8-bit data in 24 channels in the PCM format, puts in cells the PCM-formatted data in 24 channels, and sends the cells sequentially to a broadband network transmission line through the remote switching unit. On receiving the above described data in cells, an adaptor provided between the broadband network and an existing telephone network converts the data to the PCM transmission format, and sends them to the existing telephone network after adding a signaling bit to them.

Abstract: Disclosed is an image forming apparatus for forming an image on a sheet. The image forming apparatus comprises a unit for forming a toner image on the sheet and a flash fixing unit for fixing the toner image onto the sheet by an emission of light from a flash lamp. The flash fixing unit includes a first unit having a first flash lamp disposed at the center and a second unit having second flash lamps disposed on both sides of the first flash lamp and exhibiting a light emitting energy larger than a light emitting energy of the first unit. The second flash lamps disposed at a pitch smaller than the pitch at which the first lamps are disposed. With this construction, the fixing energies at both ends of the flash fixing unit increase, and the fixing energy at the center decreases. It is therefore possible to prevent an ill-fixed state and improve a fixing efficiency.

Abstract: A semiconductor device includes a semiconductor chip, a die-pad on which the semiconductor chip is mounted, a package encapsulating the die pad and the semiconductor chip, and a plurality of leads electrically connected to the semiconductor chip and projecting from the package, wherein each of the leads has a lead body made of pure nickel (Ni) having a purity equal to or greater than 99% and a first film formed thereon, the first film being made of palladium (Pd).

Abstract: A high electron mobility transistor type group III-V compound semiconductor device includes a substrate of a group III-V compound semiconductor, an electron transfer layer of a group III-V compound semiconductor formed on the substrate, an impurity doped electron supply layer of a group III-V compound semiconductor having a wider band gap and smaller electron affinity than the electron transfer layer, and a spacer layer of a group III-V compound semiconductor having a lattice mismatch with the electron supply layer, the spacer layer being formed between the electron transfer layer and the electron supply layer. A HEMT type group III-V compound semiconductor device is provided which uses an Si-doped electron supply layer of material such as InGaP other than AlGaAs and has good device properties.

Abstract: A semiconductor device includes a package substrate and a semiconductor chip provided on the package substrate, wherein there is provided a jumper substrate carrying thereon electrodes and conductor patterns that connect the electrodes, such that the jumper substrate is mounted upon the package substrate for providing an interconnection between the electrode patterns provided on the upper major surface of the package substrate in electrical connection with the electrode pads on the semiconductor chip and the electrodes that are isolated in correspondence to the through-holes provided on the package substrate.