There is currently a demand for active electronic components that function reliably at ambient temperatures over 300°C. This is especially true for instrumentation used in controlling jet engines in military aircraft. The IIL (Integrated Injection Logic) is a bipolar digital IC which has the ability to switch at temperatures higher than the TTL (Transistor-Transistor Logic).
To operate an IIL inverter at a high-temperature, its low-level output voltage must be kept at a low level and its high-level output voltage must be kept at a high level, even in high-temperature conditions. To satisfy these requirements, the built-in voltage of forward-biased junctions should be high and the leakage current of reverse-biased junctions should be low. The actual carrier concentrations are determined by comparing the experimental results from the characteristics of PN junctions with various carrier concentrations at high-temperatures.
To make the proposed original structure with high-carrier concentrations, we apply selective ion-implantation and successive epitaxy steps to the IIL, fabrication process.
The IIL, inverters made in this experiment operate at temperatures higher than 370°C.

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Today, it's remarkable that the operating systems attatch the “window system” as a user interface on the small computers such as personal computer, workstation, and so on.
In these window systems, as you know well, the “overlapping multi-window” method is used as a display control method. Although there are much merit in it, we can not disregard some demerits. One of the most undersirable situations is that when a window is enlarged or opened, some other windows may be hidden completely under the active window and become quite imvisible. To conquer this situation, several improved methods have been proposed. But, it seems that these are not focused on the center of the problem.
In this paper, we define it as a “fuzzy control” problem. Namely, the problem of recovering the windows which falled into a “disadvantageous” status by the window manipulation to the most “advantageous” status. And we propose a new method of automatic window rearrangement using fuzzy inference. Finally, we show the usefulness of the proposed method by several experiments.

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This paper investigates the coded high PRF radar which is capable of measuring the distance and velocity of moving target in wide range directly and simultaneously. The system uses radar waveform in which carrier wave of each pulse is modulated using bi-phase code of successive random sequences independent in each other. By this method, the system can expand measuring distance to the extend of sequence period having long time interval, and can measure high velocity corresponding to short sampling interval of transmitted pulses.
The system has a unique feature of the measuring distance capability under residued noise and clutter condition in contrast to conventional high PRF system using multi PRF ranging, and additionally has supression capability equal to the signal processing gain against unwanted incoming signal uncorrelated with radar signal. On the contrary, time sidelobe noise generated in the process of sequence correlation influences signal detection performance in case of receiving strong clutter. From a study on application to C-band surveillance radar operating in SEA STATE 4 clutter environment, it is found that the designed system can measure distance up to 150km (resolution 30m) and velocity up to 800m/s for moving target (radar crossection 5m²) under detection probability 0.5 and false alarm rate 10^-8

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We developed an input method of plant diagrams, which can convert paper-based diagrams efficiently to computer database. A diagram to be input contains so many elements, i. e. symbols, connection lines and characters, which are often touching each other, so that the conventional automatic input techniques were not adequate. Our method of recognition and verification together reduced the time needed to input a diagram to be 30%, compared to manual input using a CAD input terminal.
In recognizing such a diagram, we first detect elements with loops or black regions, which are apparently separable. And upon these features, the system parallelly detects and judges symbols. And the symbol recognition results are feedbacked to detect other elements, namely lines and characters. In this manner, we succeed to cope with elements, which are touching each other.

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