This paper describes a method for design of a phase-locked radio frequency (rf) control system to accelerate bunched beams in synchronism with rf. A set of transfer functions of an ion synchrotron system for suppressing phase oscillation Δφ and radial displacement ΔR of the bunched beams are derived by the use of classical control theory. The mathematical models of the beam dynamics are the same as Schnell employed previously (W. Schnell: CERN68-27, 1968) as the standpoint of the equivalent resonant circuits for the rf phase-locked beam control systems.
From the above transfer functions, the types of Δφ and ΔR controls can be determined. A simple method to obtain their control parameters is also presented. The results of simulations show the usefulness of our design technique.

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This paper describes protectors and multisensors using ferrite-magnetic semiconductor (FMS), which is a kind of ferrimagnetic substance. The useful FMS as a measuring and controlling device can be created with various Curie temperature over a wide range of -15 to 300°C, while keeping the ferromagnetic property below its Curie temperature.
The FMS's magnetic and electrical properties have temperature, humidity and gas concentration dependence, as well as a switching function. The magnetic reluctance increases with a temperature rise and approaches a high value at its Curie temperature, but is independent of humidity and concentration of combustible gas. The semiconducting resistance decreases from 225 to 170kΩ with humidity change of 50 to 90%. The FMS's specific dielectric constant above 900 is dependent on temperature, humidity and concentration of combustible gas including acetone, methanol and ammonia. In methanol, the capacity increases from 0.18 to 0.5nF with gas concentration of 0 to 850ppm. Further, bidirectional switching characteristics appear at a higher voltage range above 250V. Therefore, these characteristics are expected to be used practically in the field of protecting and measurement instruments. The overheating/ overvoltage protector with temperature/humidity/gas concentration sensors is composed of two ring-formed FMS's.

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This paper proposed IC igniter for fluorescent lamps using newly developed electronic circuit to improve the long ignition time of glow igniter that is widely used in domestic use. The IC igniter has not only short ignition time (within 2 s) but also compatibility with glow igniter since it has two terminal configuration.
Newly developed IC structure integrates high voltage transistor and field effect resistor that withstand over 1, 000V kick pulses, high current diode for over 1A preheat current of fluorescent lamp filaments, and pnpn device that detects a specific current value of the transistor and cuts off the transistor. Selective eching from the back of the silicon chip realizes high voltage isolation IC structure.

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Due to low distortion and high power efficiency over 80%, the hybrid class-BD power amplifier (HBD) is attractve for battery powered systems, but high cost on producing it of discrete parts decreases the utility.
This paper present a new architecture for the HBD amplifier suited to monolithic integration. This architecture enables to reduce a half of the high frequency power circuits based on the original architecture.
In new circuits, the signal is amplified by one unit of class-D power amplifier, unlike the original circuits by two units. The absolute value signal synthesized from input signal is amplified by the class-D power amplifier, and is feeded to the load resistor through full-bridged transistors to control load current directions. The power efficiency and harmonic distortions of the new circuits are the same as those of the original circuits.
This simplification facilitates to integrate the HBD amplifier, and enables us to reduce the size and costs.
An experimental HBD power amplifier powered by a single 9V supply based on new architecture has been fabricated. The maximum total stage power efficiency factor was 85% under 0.2% of total harmonic distortions.

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The present semiconductor thermo-electric-elements integrated into the thermo-electric units, which are commercially available, are not elaborately designed for low temperature-difference operation. Those elements available in the room-temperature range are usually applicable for the temperature-difference around 60K with relatively poor coefficient of performance. For air-conditioning purpose, it is expected for the thermo-electric-energy-conversion to have a high coefficient of performance as well as to have economical advantage because of the low temperature-difference operation.
The paper describes basic and analytical considerations for low temperature-difference operation and also the new design systems desired from viewpoints of the effective and economical exploit of environmental energy. An appropriate design allows the drastic economy in the material and also the drastic improvement in the coefficient of performance and it is possible to put the material, with the presently available figure of merit, in practical use.
The availability of a simple cascade connection is discussed for the operation under some increased temperature-difference. The concept of the cooling or heating systems using a thermoelectric units drived by a solar-cell array will be also proposed and an experimental results will be illustrated.

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In recent years, robust control design problem has drawn considerable attention because it allows one to ensure desirable closed-loop properties in the presence of model uncertainties, and several design method have been developed. In this paper, we will mainly discuss the problem of robust control design of systems with bounded uncertain parameters, and give a new design method, called “incentive design”, for this design problem. This method is mainly based on such a consideration that the designed robust control law can guarantee a most favourable value of the cost functional no matter how do the uncertain parameters vary within given bounds. Therefore, in this sense, the existence of the uncertainty in controlled systems has at least no bad effect on the optimal value of the cost functional.
In this paper, we first give the procedure for designing robust control of the systems with bounded uncertain parameters, in general. Then, for a class of uncertain linear-quadratic systems, we design concretely such a robust control law, and give a numerical illustrative example. It is shown from this derivation and this numerical example that the method proposed in this paper is effective and feasible for some practical control problems with bounded uncertain parameters. The design method developed here may be expected to have some further applications for the practical control problems in future.

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As is well-known, most of conventional studies on the sound insulation system were introduced mainly from the deterministic viewpoint in a frequency domain or based on the linear correlation technique in a time domain. However, in the actual noise environment, the resultant signal often shows a complicated fluctuation pattern apart from the usual Gaussian type, owing to the variety of phenomena and the complexity of human response, and the actual observation is inevitably contaminated very often by a background noise of arbitrary distribution type. Therefore, in this paper, an identification method of arbitrary sound insulation systems contaminated by a background noise is proposed, under the evaluation criterion based on the agreement between theory and experiment for the output probability distribution, especially by paying our attention to not only the lower order statistical information like mean and variance but also the higher order statistical one which is directly matched to the actual noise evaluation idices L_x (X=95, 90, 10, 5). Concretely, these systems are first described in a non-linear equation on the power flow in a time domain. Then, by newly introducing an error criterion on the deviation from the actually observed output probability distribution, a recurrence estimation algorithm for system parameter is introduced from three different viewpoints by use of the well-known stochastic approximation method. Finally, the effectiveness of our proposed method is confirmed experimentally by applying it to the non-parallel type double wall and sound-bridge type shielding systems which are very difficult to evaluate by the already-known theoretical analyses.

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In the field of Probabilistic Safety Assessment, evaluation of Common Cause Failure (CCF) is one of the most important problems difficult to evaluate it systematically, and many kinds of evaluation method for CCF have been developed.
The MGL (Multiple Greek Letter) method developed by K. N. Fleming is one of CCF evaluation methods. It was derived for the higher order (more than the third order) redundant systems as an extension of the β-factor method which is essentially applied only to the second order redundant systems.
Values of the parameters defined in the MGL method change with the order of redundancy due to its definition of the parameters, as an example, simultaneous failure probability of two units of the second order redundant system and that of the third order redundant system are different from each other even if failure probability of each unit has a same value.
This paper tried to modify the MGL method in order to have no change of its parameters through out all the order of redundancy.
As a result of this modification, the parameter change with the order of redundancy is eliminated, and acceptable ranges of values of new parameters are determined, while relations between new modified parameters and usual MGL parameters are obtained.
Furthermore, results of some application to practical redundant systems are shown.

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