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A stacked CdZnTe semiconductor detector, which is able to detect the 6.13 MeV γ-rays from 16N, was prototyped and the response calculation was carried out by a Monte-Carlo simulation. The detector response was simulated by using the electron and photon transport code, EGS4 and taking into account the carrier trapping phenomena. The results of the response calculation agreed with the experimental data from the checking source of 137Cs and 60Co. The prototype's response and sensitivity to 16N were calculated by simulating an incident energy of 6.13 MeV . The source spectra were unfolded with the detector's response function obtained by simulation, and it indicated that the incident γ-ray energy and its intensity ratio was identified. We have acquired the potential to measure the γ-ray energy in the high energy region about 6 MeV with the stacked CdZnTe detector.

A new mechanical alloying process for preparing amorphous powders by rubbing more than two types of elemental metal against each other under a certain pressure has been developed. A rotating bundle of Cu and Ti sticks pressed on the concave side of a Ti mortar is used to prepare a fine powder. The micromorphology of the powder was examined using scanning electron microscopy and optical metallography. Energy-dispersive X-ray spectroscopy analysis shows that the powder was not contaminated at all. The alloying procedure was investigated by X-ray diffraction analysis and differential scanning calorimetry. The fine powder mechanically alloyed for several hours showed the broad X-ray scattering maxima and the exothermic heat peak of thermal analysis curve referring to the amorphization and crystallization, respectively.

The purpose of this study is to establish a one dimensional large displacement theory for plane-curved members with thin-walled open sections. Consequently, this theory is applied in the analysis of lateral-torsional buckling of circular arches. Typical numerical examples are shown herein to illustrate how the ratio of different types of rigidities in non-dimensional form affects the buckling loads.

summary Up to this time, it has been difficult to recognize defects of machine and equipment by automatic system instead of skilled human sensors. Now authors have developed the new art which can catch the specific features of acoustic signal from rotating machines using diagnostic signature analysis. As a result, the automated inspection and diagnosis of the rotating state of motors have become possible. For the diagnostic analysis, the pattern recognition technique composed of signal averaging and normalization method is used. Especially, the statistical classifications using a characteristic function and an estimated function have proved their usefulness. A practical inspection equipment based on this analysis for rotating machines has been developed and tested in one of our plants. This statistical methods can be also applied to the preventive maintenance and automatic diagnostic system for other kinds of machines, tools and various kinds of plants.

A finite element method is applied to compute the elastic-plastic post-buckling behavior of initially deflected and eccentrically loaded steel plates and box sections. Comparisons with available theoretical and experimental results reveal that the present finite element analysis gives extremely accurate results even with small numbers of elements. Based on an extensive numerical study, an empirical formula is proposed to predict the ultimate strength of steel plates as well as steel box sections with various supporting conditions.

Oxygen precipitation in CZ silicon crystal depends on the existence of an ambryo. During crystal growth embryos are assumed to form at carbon atoms. We simulated the embryo formation based upon a thermally-activated heterogeneous nucleation model. Results for the case of an isothermal pre-anneal agree with experiment for homogenized wafers with various carbon content. Results for the cooling process during crystal growth indicate that the thermal history during tailing and slow cooling determine embryo formation in a large part of a silicon crystal with a larger diameter and reduced carbon content.

A ray-theoretical approach is attempted to interpret radial eigenfunctions (radial and tangential displacements) of spheroidal modes of a homogeneous elastic sphere. It is shown that surface displacements of the mode solutions agree well with those expected when relevant body waves are incident on the free surface. The possibility of interpreting amplitude dependence on depth in terms of interference phenomenon of up-going and down-going body waves is also demonstrated. The radial eigenfunctions are computed for a variety of spheroidal modes with relatively high radial mode numbers. An interesting feature is found in these functions: The number of node surfaces in the radial distribution of the radial displacement increases systematically for a given radial mode in conformity with a change of surface value of the tangential displacement from negative to positive with increasing colatitudinal order number.