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In the development of sound isolation type generators, a three-division case structure divided into two cool zones and one hot zone was studied. This study was aimed at achieving compatibility between sound isolation and cooling capabilities that are in a trade-off relationship. Sound isolation of 12.1 dB(LWA) was achieved by this structure, while obtaining equivalent cooling capabilities to that of open type generators. As a result of adopting this new generator structure for India domestic consumption, the compliance with the Indian noise regulation phase II was achieved for the first time by a mass produced generator.

Dimethyl ether (DME) has been attracting notable attention as a clean alternative fuel for diesel engines. The authors developed a medium duty DME truck, and investigated aspects of vehicle performance such as engine power, exhaust characteristics, fuel consumption, noise, in-vehicle systems, and so on. Results indicated that higher engine torque and power could be achieved with DME compared to diesel fuel operation of the base engine at any engine speed. Results also showed that emissions decreased dramatically, to 27% for NOx, 74% for HC, 95% for CO and 94% for PM (Particulate Matter) compared to maximum allowed Japanese 2003 emission regulations. The operating noise of the DME vehicle was slightly lower than the base vehicle with diesel fuel, because the combustion noise with DME was decreased compared to with diesel fuel operation. The DME vehicle was given a public license plate in October 2004, after which running test continued on public roads and on a test course.

In this report, trace levels of harmful substances, such as formaldehyde, acetaldehyde, SO2, benzene and so on, emitted from a DME fueled direct injection (DI) compression ignition (CI) engine were measured using a Fourier Transform Infrared (FTIR) emission analyzer. Results showed that the NO portion of NOx emissions with DME exceeded diesel fuel operation levels. DME fueling caused greater amounts of water than with diesel fuel operation. DME fueling was also associated with higher formaldehyde emissions than with diesel fuel operation. However, using an oxidation catalyst, formaldehyde could be decreased to a negligible level.

Characteristics of dimethyl ether spray formation were observed using schlieren photography, and the combustion characteristics and performance of a dimethyl ether-operated diesel engine were investigated. Accordingly, this paper describes the basic characteristics of engine performance and the potential for decreased exhaust emissions, as well as discussing problems concerning the practical application of dimethyl ether-operated diesel engines.

Japan National Oil Corporation (JNOC) has been tackling the technical research and development of natural gas conversion technology since FY1998 in collaboration with five Japanese private companies in order to aim at establishing the option technology to explore stranded gas reserves. The Syngas section of JNOC's GTL process applies the steam/CO2 reforming and the FT section employs the slurry reactor with Ru- or Co- catalysts. JNOC's GTL process is capable of utilizing CO2 contained in the natural gas and does not require any O2 supply. Namely, the characteristics of JNOC's GTL process in contrast to those of the existing ones using ATR or POX are (1) no use of the O2 plant, (2) no use of the CO2 separation unit, and (3) no use of the H2 conditioning unit. Such facility savings will bring about a remarkable reduction of the plant cost for its election and operation.

The smaller and lighter SV-06 sliding vane type compressor has been developed as the successor of the swash plate type 10P08 compressor for mini-car air conditioning applications. The SV-06 is the first vane type compressor in the world which utilizes an aluminum cylinder and rotor to achieve weight reduction. This was accomplished by introducing several new features to the design, such as a boron treated vane and smooth cylinder profile. Thinner vanes and a high performance oil separator were also introduced for compactness. This paper presents the many design features that allow small size and low weight while maintaining compressor performance and reliability, and focuses on the most important technology: (1) Abrasion Characteristics of Boron Treated Vane Against Al-Si Alloy (2) Oil Separator Performance

ASP-I and ASP-II (under development) are the CMOS single chip signal processor designed for the purpose of the sound field control for the electronic acoustic instruments. ASP-I, II are provided with the audio signal interface control, Multiplying/accumulating operation, external RAM control and IIR digital filter operation, and these operation can be performed concurrently. Plural IIR digital filter operation realizes the simulation for the frequency characteristic of reflection sound, and external RAM control as ring buffer realizes the echo pattern operation. With these features, the ASP-I, II can reproduce the realistic sound field of music halls, churchs, ect. and can control the sound field freely.