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131.
Wool fibres are subjected to severe mechanical actions during the worsted-spinning process, especially on a high-speed system. The loss of crimp and crimp recovery of single wool fibres are examined by measuring the crimp shrinkage of single fibres and the bulkiness of fibre bundles sampled at various stages in a commonly used worsted-spinning system. It is found that the crimp and crimp recovery of single fibres gradually decrease with progress through the spinning system, the reduction being particularly noticeable during carding. Fibre bundles with a high crimp level showed greater bulkiness. 相似文献
132.
The “linearizing method” is a method used to predict the stress/strain relation of fabrics under biaxial extension in the warp and weft directions. The stress/strain relation is firstly linearized by using a transformed strain such as ei = ?i n where ei is the transformed strain (i =1, 2), ?i the strain, and n a constant, and the stress Fi is then expressed by a linear equation in ei. The elastic parameters are determined by strip–biaxial–extension experiments in the warp and weft directions. This method was proposed by Kawabata in 1985 without sufficient examination of its validity. In this paper, the validity of the method is inspected by biaxial–extension experiments for various kinds of fabric. It is concluded that the linearizing method has sufficient capacity to enable the biaxial–extension behaviour of the fabric to be estimated with considerable accuracy. For the case when the stress/strain relation is linearized in two zones of strain, the double–zone linearization is presented here to improve the accuracy of prediction and to expand the validity of this method over a wider range of strains. 相似文献
133.
The authors have shown that special formulations are required to give complete covering of steel surface (with no swelling, break away, cracks, etc) with flame sprayed film coating of epoxy resin. For this purpose, there should be minimum stress in the film, and it was concluded that treatments effective for this purpose involve adding adequate filler to reduce the thermal expansion coefficient, controlling the degree of cure, holding small closed pores in the film and semi-curing immediately after spray to keep the required tensile strength. 相似文献
134.
135.
Influence of cardiac motion on diffusion-weighted magnetic resonance imaging of the liver 总被引:1,自引:1,他引:0
Thomas C. Kwee Taro Takahara Tetsu Niwa Marko K. Ivancevic Gwenael Herigault Marc Van Cauteren Peter R. Luijten 《Magma (New York, N.Y.)》2009,22(5):319-325
Purpose
To assess cardiac motion-induced signal loss in diffusion-weighted magnetic resonance imaging (DWI) of the liver using dynamic DWI. 相似文献136.
M Niwa H Oyama T Kobayashi Y Kida T Tanaka S Maesawa M Furuse S Inao J Yoshida 《Canadian Metallurgical Quarterly》1997,37(11):825-8; discussion 828-9
The effect of glycerol on blood flow in tumoral and peritumoral tissue was measured in 32 patients with brain tumor, 17 gliomas and 15 meningiomas. Blood flow before and after the administration of glycerol was measured by stable xenon-enhanced computed tomography. The tumor part of glioma was significantly hypoperfused. In contrast, the tumor part of meningioma was significantly hyperperfused. Peritumoral edema of both glioma and meningioma was hypoperfused. After the administration of glycerol, blood flow increased in all regions except for the tumor part of glioma. Vascular responses to glycerol may be different in these two tumor types. The steal phenomena of blood flow might occur in cases of glioma. 相似文献
137.
Hideo Fujitani Masaomi Teshigawara Wataru Gojo Yoshinobu Hirano & Taiki Saito 《Computer-Aided Civil and Infrastructure Engineering》2005,20(1):62-77
Abstract: This article proposes a new framework for performance-based design (PBD) of building structures. This framework was proposed under the 3-year Japanese Government Comprehensive Research and Development Project on "Development of a New Engineering Framework for Building Structures" launched in the fiscal year of 1995. The primary objective of the project is to create a system in which the performance of buildings is clearly stated, and consumers, that is, occupants, are well informed of how their buildings will perform and how much it will cost to maintain their performance. The framework emphasizes the establishment of target performance, the performance evaluation, and the performance statement as the main three elements. It also stresses that an institutional framework and support systems need to be provided to enable PBD to be practiced efficiently. The implementation of the proposed framework is also expected to promote engineering innovation, progress in building engineering, and globalization. The new framework will also bring other benefits, such as improved design techniques, greater design flexibility, and international harmonization. It is also important for building structural performance to become one of the most important indexes for consumers to define a building's value. The Japanese building code was changed to the performance-based code, based in the clear and comprehensive manner proposed in this article. In the United States, "Vision 2000" ( SEAOC, 1995 ) was published, then many research activities were conducted simultaneously. 相似文献
138.
Sanae Shimizu Kazuhiko Yamamoto Caihau Wang Yutaka Satoh Hideki Tanahashi Yoshinori Niwa 《Electrical Engineering in Japan》2005,152(3):29-38
Moving object detection with a mobile image sensor is an important task in robotics and computer vision, when considering the practical use of robotics in human environments. In this paper, we propose a robust method that detects moving objects in the environment using the omnidirectional depth information obtained by a mobile Stereo Omnidirectional System (SOS). In order to detect only the moving objects within the depth image that are obtained by a sensor in motion, we first estimate the ego‐motion of the sensor, and generate a predicted depth image for the current time from the depth obtained at the previous time by only considering the ego‐motion of the sensor. Then the predicted depth image is compared with the actual one obtained at the current time, and the inconsistent regions are detected as moving objects. When the sensor moves, occlusions will occur in the scene and they will cause false detections. However, these false detections can be suppressed by estimating the occlusion regions using the ego‐motion parameters of the sensor and the jump edges in the depth image. The effectiveness of the method is shown with experimental results for a real environment. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 29–38, 2005; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20155 相似文献
139.
Hydrothermal flames in supercritical water oxidation: investigation in a pilot scale continuous reactor 总被引:1,自引:0,他引:1
Roberto M. Serikawa Takashi UsuiTatuya Nishimura Hirokazu SatoShusaku Hamada Hideo Sekino 《Fuel》2002,81(9):1147-1159
Hydrothermal flames at 25 MPa supercritical water environment were investigated using a 4800 ml reaction tower, in which the sapphire windows were fitted for optical access. Down flowing hydrothermal flames were observed for oxidation of 2-propanol when the reactor was fed with inlet organic concentration higher than 2 vol% and air ratio higher than 1.8. Flame temperature, as high as 1100 °C, was measured by means of a thermocouple and the temperature was found to be strongly influenced by air ratio. Effective and stable oxidation of organics with TOC removal rate of 99.9% was achieved. Dioxins were also decomposed with a ratio higher than 99.9%, within 1 min reaction time in this reactor configuration. 相似文献
140.