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91.
Hiroi Masato Hojo Masayuki Hashimoto Yukio Abe Yoshikazu Dote Yasuhiko 《Industrial Electronics, IEEE Transactions on》1986,(2):110-113
A methodology of discontinuous feedback and continuous feedforward control is developed to achieve accurate decoupled tracking in a class of nonlinear, time varying systems in the presence of disturbances, parameter variations and nonlinear dynamic interactions. The method is based on an improved variable structure control with a sliding mode. 相似文献
92.
It is reported that laser-processing is effective to repair the heat checks, which are fine shallow cracks on a surfaceof die-casting dies. 相似文献
93.
Masato Yamamura Takatoshi NishioToshihisa Kajiwara Kitaro Adachi 《Chemical engineering science》2002,57(15):2901-2905
The ordered necklace-like or cellular pattern formation has been investigated for ternary polymer solutions in which primary and secondary phase separations were induced by the solvent evaporation. The patterns consisted of regular droplet arrays of various diameters, which arose in the pre-existing polymer phases via the secondary phase separation. The pattern formation was enhanced with increasing air velocity and ambient humidity, while it was suppressed with decreasing initial film thickness. The regular pattern was independent of surface wettability of the solid substrate. We ascribe the morphology change to the evaporation-induced surface tension driven convection, which re-arranged the droplet distributions from disordered to flow-induced ordered patterns. 相似文献
94.
Kisaragi Yashiro Masato Naito Yoshihiro Tomita 《International Journal of Mechanical Sciences》2002,44(9):1845-1860
Molecular dynamics simulations are conducted on the dislocation behavior at the apices and edges of cuboidal Ni3Al precipitate in a pure Ni matrix, or the idealized γ/γ′ microstructure in a Ni-based superalloy. A tensile simulation of the [001] direction is implemented with a periodic cell that has eight cubic precipitates in order to investigate the nucleation site of dislocation in the idealized microstructure with no defects other than the γ/γ′ interfaces. The effect of residual internal stresses on the stability of the interfaces is also discussed. Other simulations are conducted on the behavior of edge dislocations nucleated from a free surface and proceeding in the γ matrix toward γ′ precipitates under shear force. Dislocation pinning at γ′ precipitates, bowing-out in the γ channel, pile-up and nucleation of superdislocation in the γ′ precipitate are simulated and inspected in detail. Discussions on the size of the γ/γ′ microstructure and the sharpness of the edge of the γ′ precipitate are also presented. 相似文献
95.
Mizuki Ono Tsunehiro Ino Masato Koyama Akira Takashima Akira Nishiyama 《Solid-state electronics》2004,48(12):2191-2198
It is shown that propagation delay time in CMIS (complementary metal insulator semiconductor field effect transistor) inverters is strongly affected by dielectric constant nonuniformity in gate dielectrics caused by the phase separation in silicate films. Influences of such nonuniformity on load capacitance are studied by analytical calculations based on a physical model which takes polarization into account. It is newly found that load capacitances are affected by the phase separation in qualitatively different ways, depending on the average metal concentration of their dielectric films. An experimental result is compared with those calculations. Influences of such nonuniformity on current drivability are studied by 3-dimensional device simulations. It is also newly found that such nonuniformity affects load capacitance and current drivability in different ways, resulting in an increase in propagation delay time of CMIS inverters for all metal concentrations studied. An explanation of this phenomenon is given with physical considerations. 相似文献
96.
Maohong YU Yoshiya ODA Dongping FANG Junhai ZHAO 《Frontiers of Architecture and Civil Engineering in China》2008,2(1):1-25
Chinese ancient architectures are valuable heritage of ancient culture of China. Many historical building have been preserved
up to now. The researches on the structural mechanics of ancient architectures show the different aspects of structure and
mechanics. Systematical studies on the structural mechanics of ancient architectures have been carried out at Xi’an Jiaotong
University since 1982. It is related with the need of repair of some national preservation relics in Xi’an. These studies
include: 1) Ancient wooden structures including three national preservation relics Arrow Tower at North City Gate, City Tower
at East City Gate, and Baogao Temple in Ningbao, Zhejiang province. 2) Ancient tall masonry building, the Big Goose Pagoda
and Small Goose Pagoda in Xi’an. 3) Mechanical characteristics of ancient soil under foundation and city wall; the influence
of caves in and under the ancient City Wall on the stability of the wall. 4) The typical Chinese ancient building at the center
of city: the Bell Tower and Drum tower. 5) The behavior of Dou-Gong and Joggle joint of Chinese ancient wooden structure.
6) The mechanical behavior of ancient soils under complex stress state. A new systematical strength theory, the unified strength
theory, is used to analyze the stability of ancient city wall in Xi’an and foundation of tall pagoda built in Tang dynasty.
These researches also concern differential settlements of Arrow Tower and resistance to earthquake of these historical architecture
heritages. Some other studies are also introduced. This paper gives a summary of these researches. Preservation and research
are nowadays an essential requirement for the famous monuments, buildings, towers and others. Our society is more and more
conscious of this necessity, which involves increasing activities of restoration, and then sometimes also of repair, mechanical
strengthening and seismic retrofitting. Many historical buildings have in fact problems of structural strength and stability;
the need for further studies on structural mechanics and materials is definitely growing.
__________
Translated from Advances in Mechanics, 2006, 36(1): 43–64 [译自: 力学进展] 相似文献
97.
Nao-Aki Noda Akifumi Inoue Masato Nagawa Fumitaka Shiraishi 《International Journal of Pressure Vessels and Piping》2002,79(12):807-818
This paper deals with a new seal system between flange joints without using a gasket. This gasketless flange includes a groove and an annular lip that is machined in one of the flange rings which when removed being in contact with the other flange to form a seal line when the flanges are assembled. In this study, firstly, fundamental dimensions are examined for unplasticized polyvinyl chloride (PVC-U JIS) to obtain the best sealing performance. Then, the effects of material difference and flange nominal size upon the sealing performance of the new gasketless flange are investigated for two types of materials, 0.25% carbon steel (S25C JIS) and PVC-U. It is found that the critical internal pressure at which leakage appears is mainly controlled by the maximum stress at the annular lip for each material even if the flange nominal sizes are different. The gasketless flange made by PVC-U shows the higher critical internal pressure compared with the case of S25C if the same clamping forces are applied. The effect of stress relaxation for PVC-U on the sealing performance is also considered. Then, it may be concluded that this PVC-U gasketless flange as well as S25C has good sealing performance. 相似文献
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