Synchrotron radiation plays a crucial role in the analysis of valence states which play an important role in the function of materials. In this paper, the development and application of the analysis using synchrotron-radiation-based soft X-rays are outlined, and the research expected in the next generation synchrotron radiation NanoTerasu is commented.

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To determine the role of leptin in endotoxin-induced anorexia in ruminants, circulating leptin levels were measured during acute experimental endotoxemia in sheep. Injection of bacterial lipopolysaccharide (450 ng/kg, i.v.) induced anorexia accompanied with fever and increases in serum levels of cortisol, insulin and glucose which are known to stimulate leptin secretion in rodent and human, while it did not affect serum leptin levels at all. These results indicate that serum leptin levels in sheep during acute endotoxemia are differentially regulated from those in rodent and human, and that leptin might not be involved in the endotoxin-induced anorexia in sheep.

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The strain in the bulk of material was evaluated using high energy white X-rays from a synchrotron radiation source of SPring-8 in Japan. An austenitic stainless steel (JIS-SUS304L) was used for a specimen. The specimen of 5mm thickness was subjected to the bending. The internal strain of it could be measured using white X-rays which range of energy from 60 keV to 125 keV. The measurement of the internal strain with a high accuracy was accomplished using the strain data from several lattice planes of γ-Fe simultaneously. Furthermore, the measurement error of strain could be decreased by using the diffracted beam with high energy, high peak count and the similar profile with the Gaussian distribution. The results showed that the high energy white X-rays is effective for the internal strain measurement in the depth of the order of millimeter.

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Residual stresses which occur in a thin plate and a film of both MEMS and an electric device have become a direct cause of a deformation and a destruction of them. To evaluate the residual stress is therefore very important for improving their mechanical reliability. A strain gauge is often incapable of using to measure the strain of the thin plate and the film, while X-ray diffraction method is effective in the nondestructive measurement of residual stress of them. If a diffracted X-ray transmitted through the thin plate is available, spacing of the lattice plane orthogonal to the direction along the surface could be measured directly. It suggests potentiality for the strain measurement of thin plate with high precision and efficiency. This paper presents a new measurement method of the stress in a polycrystalline thin plate by using transmission diffracted X-rays. This method is able to determine the principal stress and its direction in the thin plate from the measurement of the lattice spacing with random three directions within thin plate and the vertical direction of thin plate surface. The method was verified using a pure aluminum thin plate of 50μm thickness which was loaded with tension using compact tensile loading equipment. The X-ray elastic modulus of Al(311) lattice plane which was measured at the start of the experiment was derived as Young's modulus of 61.7GPa and Poisson's ratio of 0.33. As a result, principal stress and its direction in the aluminum thin plate could be evaluated with errors of less than about 9MPa and 3degree, respectively. It was confirmed that this method is effective for the stress measurement of thin plate.

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High-energy X-rays from a synchrotron radiation source, SPring-8, are available to obtain the microstructural information at deep positions inside the materials, because of its large penetration depth. Using the high-energy X-rays with an energy level of about 73keV, the internal stress in the bond coating was measured through the top coating in the thermal barrier coatings (TBCs) which consisted of a zirconia top coat with thickness of 0.24mm and a NiCoCrAlY bond coat with thickness of 0.2mm. A furnace, which could heat up the specimen up to 1473K was developed for the purpose of the in-situ stress measurement of the TBC in the goniometer at Beam Line BL02B1 of SPring-8. The diffraction of Ni₃Al-311 from the bond coat obtained through the top coat with about 0.24mm thickness was strong enough for stress determination. The internal stress in the bond coating was measured at the room temperature, 773K, 1073K and 1373K. The internal stress in the bond coat at a room temperature was tensile, and it was decreased with increase in temperature. At 1073K or higher, the internal stress in the bond coat was released due to softening of the bond coat. The change of internal stresses in the bond coat with temperatures was explained by thermal mismatch of expansion between top and bond coats.

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This paper described a new nondestructive measurement of the in-depth distribution of residual stresses by using monochromatic high energy X-rays from synchrotron radiation source of SPring-8. The measurement was carried out by using the sin²ψ method with the Ψ-diffractometer. It was first proved to have a high accuracy in measuring the loading stress by four-point bending.
The diffractions with five different penetration depths obtained by X-rays with three energy levels, 30, 60, and 72keV, were adapted to measure the residual stress below the surface of shot peened steels. The residual stress distribution measured by five penetration depths agreed well with the residual stress distribution determined by the conventional Cr-Kα radiation combined with the method of the successive removal of the surface layer by electropolishing. The compressive zone extended 150 and 300μm below the surface depending on the intensity of shot peening.

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Deformation properties of austenitic stainless steel foils of 0.05 mm in thickness were evaluated by using transmitted polychromatic X-rays under monotonic tensile loading. A conventional laboratory X-ray equipment with a rotating Mo anode was adopted at a tube current of 40 mA and an acceleration voltage of 60kV. Soller slits with a divergence angle of 0.5 deg were attached on both divergent and receiving sides. By the preset time of 500s, enough diffraction intensity was obtained to determine the stress. The diffraction elastic constants were measured under monotonic loading by the cos²χ method. The diffraction energy decreased almost linearly with increasing cos²χ, and the slope of the cos²χ diagram decreased with increasing applied stress. Measured diffraction elastic constants were compared with the theoretical values calculated by the Kröner model. The experimental value obtained from a single peak with high intensity agreed well with theoretical one, and the standard deviation was enough small. The lattice strain measured during plastic deformation depended on the diffraction plane. For the single peak profile, the full width at half maximum increased with applied plastic strain. From the the diffraction-plane dependence of the lattice strain, the full width at half maximum and the diffraction intensity, deformation properties of the materials can be evaluated. Diffraction method of laboratory polychromatic X-rays is effective as a simple technique to measure multiple X-ray parameters.

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Accurate values of X-ray elastic constants are required for a reliable stress measurement of thermal barrier coating films (TBC films). In this paper, atmosphere and pressureless plasma sprayed TBC films were removed from substrates, then X-ray elastic constants of both TBC films were determained by using newly developed tensile jig. For the atmosphere plasma sprayed film, the value of the mechanical elastic constant was much smaller than the X-ray elastic constant owing to cracks or pores existing in the films. The X-ray elastic constant of the atmosphere plasma sprayed TBC film was nearly equal to that of the pressureless plasma sprayed film. This means that the X-ray elastic constants are little influenced by cracks or pores. Residual stress distributions in both films coated on the substrates were obtained. In the surface region with the depth up 60 μm, residual stresses of both films showed a drastic variation. This variation of the residual stresses was build up during rapid quenching and solidifying of the molten droplet. In deeper regions, residual stresses were nearly constant. These constant values of residual stresses are caused by the thermal strain mismatch between the TBC film and the substrate.

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When electricity supply is interrupted due to a fault, it is of primary importance to restore the power system promptly according to an adequately planned restoration procedure. Recently, power system restoration problems have received much attention in the literatures.
This paper proposes an efficient restoration procedure by making use of the linear programming. in which a restoration problem is formulated as a minimum cost flow problem and solved by the LP algorithm. Assumptions postulated in this approach are: (1) the priorities in restorative operations have been mapped on to the costs of branches, (2) available power sources are allocated to source nodes, and pre-falut loads to sink nodes, and (3) the optimal restorative plan is decided from a solution of the optimal flow.
The proposed approach has been applied to the practical power system restoration problem, resulting appropriate solutions.

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This paper presents a basic research on a measurement of strain in the bulk of materials by using high energy white X-rays from a synchrotron radiation source of SPring-8. WEL-TEN780E (JIS G3128 SHY685) whose grain size was 13μm was used as a specimen shaped into G type. The specimen was loaded with bending. The white X-ray beam, which has a height of 50μm and width of 300μm, was incident in the specimen with the Bragg angle θ of 5degree. Bending strain at the surface of specimen was measured by a strain gauge. The strain in the loading direction of the specimen was obtained directly from a rate of change of peak energy of transmitted X-rays through the thickness. As a result, the internal strain of SHY685 of 5mm thickness could be evaluated using white X-rays which range of energy from 60keV to 150keV. It is suitable for the measurement with sufficient accuracy to include more than or equal to 5000 grains of crystal in the gauge volume. The measurement error of strain could be decreased by using the diffracted X-rays with high energy. Furthermore, the measurement with a high degree of accuracy was accomplished using α–Fe321 diffraction in this material. The results showed that the high energy white X-ray is effective for internal strain measurements.

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本論文においては, 角型構造の大規模多目的線形分数計画問題に焦点をあて, 問題の定式化に携わった専門化の人間としての判断をより適切に表現するために, パラメータのあいまい性がファジィ数として特性づけられるファジィパラメータを含む角型構造の大規模多目的線形分数計画問題の定式化を行う.また, すべてのファジィパラメータのメンバシップ関数の帰属度がα以上となるパラメータ設定の中で特に意思決定者にとって最も望ましい設定が選択される非ファジィなα-多目的線形分数計画問題とともにパレート最適解の概念を拡張したα-パレート最適解を導入する.さらに, 意思決定者が主観的に設計した基準値にミニマックスの意味で近いα-パレート最適解をDantzing-Wolfeの分解原理とRitterの分割法の適用により効率的に求め, もし意思決定者が満足しなければ対話的に基準値を更新することによりα-パレート最適解集合の中から意思決定者の満足解を導出する対話型意思決定手法を提案する.

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The X-ray diffraction method has been already established as one of the most effective nondestructive evaluation method of a stress in crystalline materials. Since white X-ray beam has a wide wavelength range, a diffraction angle has to fix during a measurement to obtain a lattice spacing using the Bragg’s low. Therefore, the white X-ray method has some different features from the characteristic X-ray method. For example, the information of lattice spacing of many lattice planes in a material can be obtained simultaneously on the same diffraction angle. Because all equipment are held fixed position during a measurement, it is advantageous to in-situ measurement under the special environment such as high temperature or high pressure. In the present review article, a brief history of development of the white X-ray method is covered and some factors related to the measurement accuracy is explained. Fundamentals of the measurement system using white X-ray and the energy dispersive method are presented. Applications of the method using white X-ray obtained from a rotating target type X-ray generator to the measurement of residual stress of a surface ground material and a coating material are described. Furthermore, applications of the method using high energy white X-ray generated in the synchrotron radiation facility SPring-8 to the measurement of internal strain of a material loaded by four-point bending and strain distribution in the vicinity of crack tip in a material introduced a fatigue crack are also described.

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