Winding Method to Reduce Vibration and Loss Caused by Fractional Slot of Synchronous Machine

Fractional‐slot windings are widely used in rotating machines in order to improve the output voltage waveform, increase the design flexibility, and gain many other advantages. However, fractional‐slot windings are known to produce different harmonic components such as an even order and/or fractional number of space flux harmonics compared to integral‐slot windings. These harmonics may increase stray losses and cause stator core vibration. This paper describes an analysis of space flux harmonics and proposes new winding methods such as “novel interspersed windings” to reduce these harmonic components. The proposed winding methods were verified by numerical analysis and model tests.     

Development of –1 MV DC Filter and High‐Voltage DC Measurement Systems for ITER NBI

This paper presents the development results of a ?1 MV dc filter and dc measurement systems for an ITER (International Thermonuclear Experimental Reactor) neutral beam injector (NBI) system. High accuracy of 0.5% and fast responsivity of 3.3 μs, ?3 dB are required for the dc measurement systems: both dc voltage dividers and DCCTs. Circuit design and thermal flow design were carried out to clarify and minimize their effects on the accuracy and responsivity. The validity of the established design was demonstrated by the actual‐product tests; temperature rise of each components fell below the allowable value; inner components of dc filter withstood dc ?1.2 MV; each voltage divider accurately measured the voltage during the dc ?1.2 MV withstand voltage test; the voltage dividers and the DCCTs were adequate to the requirements of responsivity (3.3 μs, ?3 dB).     

Regional noise prediction and management system using remote sensing

Abstract

This paper deals with the prediction and management of regional and environmental noise using remote sensing techniques. Landsat-MSS and -TM data are used to estimate noise pollution by means of a group method of data handling. They estimate ground roughness from the proportion of the area occupied by buildings thus determining the shielding factor of noise propagation on the ground. The noise level predicted by the method presented in this paper showed a satisfactory agreement with that obtained from measurements from various other cases in urban areas.     

Effect of deformation mode,dynamic recrystallization and twinning on rolling texture evolution of AZ31 magnesium alloys

In order to obtain quantitative relationship between (0002) texture intensity and hot rolling conditions, conventional rolling experiments on AZ31 magnesium alloys were performed with 20%–40% reductions and temperatures within the range of 300–500 °C. Shear strain and equivalent strain distributions along the thickness of the rolled sheets were calculated experimentally using embedded pin in a rolling sheet. Rolling microstructures and textures in the sheet surface and center layers of the AZ31 alloys were measured by optical microscopy (OM), X-ray diffractometry (XRD) and electron back scatter diffraction (EBSD). Effects of the rolling strain, dynamic recrystallization (DRX) and twinning on the texture evolution of the AZ31 alloys were investigated quantitatively. It is found that the highest (0002) basal texture intensities are obtained at a starting rolling temperature of 400 °C under the same strain. Strain–temperature dependency of the (0002) texture intensity of the AZ31 alloy is derived.     

DISTRIBUTION OF ASCORBATE OXIDASE ACTIVITIES IN THE FRUITS OF FAMILY CUCURBITACEAE AND SOME OF THEIR PROPERTIES

Activities and some other properties of ascorbate oxidases (AAO) from the fruits of family Cucurbitaceae were investigated. The peel and the flesh of seven varieties had activities ranging between 35–56500 units/mg protein and 14–1250 units/mg protein, respectively. AAO from different varieties had a similar pH optimum of around 6–6.5 and a broad pH stability ranging from pH 5 or 6 to pH 10 or 11. These properties appear to be conserved in the AAO's from the family of Cucurbitaceae. The AAO's of melon cv. andes, kinsho and papaya were more susceptible to heat denaturation than AAO from pumpkin.     

Optimized Energy‐Saving Speed Profile in Linear‐Motor Railway System

The most striking characteristic of linear‐motor railway system is that the structure consists of a primary and secondary linear induction motor (LIM). The primary side of the LIM is installed in a rolling stock, and the secondary side of LIM is installed on the track. The magnetic attractive vertical force produced by the LIM increases the running resistance since this force is in the same direction as the gravitational force due to which rolling stocks gain weight virtually from the track side of view. In addition, the efficiency of the LIM has different characteristics of efficiency compared with the rotary motor. Previous studies have focused on the design method of LIM to improve motor efficiency and decrease energy consumption. However, it is a well‐known fact that this kind of approach requires hardware renewal which requests large amount of investments. The purpose of this study is to analyze these characteristics of LIM effects and design the optimal speed profile to minimize the energy consumption as a linear‐motor railway system. This smart and economic energy‐saving approach is based on the optimization of speed profiles of the linear‐motor railway system using dynamic programming.     

Enhanced angular current intensity from Schottky emitters

Even though the Schottky emitter is a high‐brightness source of choice for electron beam systems, its angular current intensity is substantially lower than that of thermionic cathodes, rendering the emitter impractical for applications that require high beam current. In this study, two strategies were attempted to enhance its angular intensity, and their experimental results are reported. The first scheme is to employ a higher extraction field for increasing the brightness. However, the tip shape transformation was found to induce undesirably elevated emission from the facet edges at high fields. The second scheme exploits the fact that the angular intensity is proportional to the square of the electron gun focal length [ Fujita, S. & Shimoyama, H. (2005) Theory of cathode trajectory characterization by canonical mapping transformation. J. Electron Microsc. 54 , 331–343], which can be increased by scaling‐up the emitter tip radius. A high angular current intensity (J_Ω∼ 1.5 mA sr⁻¹) was obtained from a scaled‐up emitter. Preliminary performance tests were conducted on an electron probe‐forming column by substituting the new emitter for the original tungsten filament gun. The beam current up to a few microamperes was achieved with submicron spatial resolution.     

大型高炉超短工期大修技术

高炉约每15年就要进行一次大修,大型高炉采用传统施工方法大修工期大约需要130天.JFE钢铁公司开发了比传统施工方法工期减少一半的大件施工法(Large Block Ring Construction Method),1998年千叶厂6号高炉大修创造了62天的世界最短工期记录,2005年福山厂5号高炉大修采用同一施工法又将记录缩短到58天.传统的施工法以10～20t为单位进行炉体拆除、安装,而大件施工法则以2000t的大件为单位进行炉体的拆除、安装,是一种全新的施工方法.     

对苯二甲酸降解微生物的驯化及筛选

从涤纶织物加工厂废水处理系统中取活性污泥获得菌源，分别提供不同的培养条件，经约40d驯化筛选得到约200株对苯二甲酸(TA)降解微生物．采用平板分离法分离出186株，通过对其分解能力的测定，又选出生长势态良好的28株，其中9-18B菌株对TA降解率接近100％。     

A successive estimation scheme of an occupation probability†

This paper treats of an estimation problem of an occupation probability of some targets in a Tegion M by an infra-red detector followed by a threshold device in a satellite.

First, a successive estimation scheme is proposed for an estimation problem of an occurrence probability of signal 1 of the 1,0 type binary signal sequence disturbed by some noise. The estimate obtained by this scheme is shown to converge to the true value with probability one and in the mean square. Then, as an application of this scheme for the occurrence probability, an estimation scheme for an occupation probability is proposed. Two examples illustrating the scheme for an occupation probability are presented.