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101.
Historically, Japan constructed its socio-cultural system so that it introduced, adopted, assimilated, and developed Western technology selectively without spoiling its own indigenous culture. And until recently, Japan learned and assimilated global best practices without being dependent on mergers and acquisitions (M&A). M&As in Japan were the lowest in the world until 2000, suggesting a low dependence on acquiring technology in this way. Recently, the number of M&As has increased dramatically among certain Japanese manufacturing firms. Prior to 2004, these firms were less profitable than their counterparts that did not depend on M&A. Today Japan's corporate technology and innovation strategy is at a crucial inflection point of maintaining the indigenous learning/assimilation function while also becoming more dependent on M&As. This paper explores the changing role of M&As in Japanese firms, and also considers the role of Web 2.0 and Enterprise 2.0 in the innovation process. Using an empirical analysis of the trajectories of Japan's leading electrical machinery firms, this paper explores the changing role of M&A in the context of business innovation in Japan, and the ongoing dialectic between indigenous strengths and global best practices. 相似文献
102.
M. ONO W. NAKAO K. TAKAHASHI K. ANDO 《Fatigue & Fracture of Engineering Materials & Structures》2007,30(12):1140-1148
Alumina is used in various fields as a machine component. However, it has a low fracture toughness, which is a weakness. Thus, countless cracks may be initiated randomly by machining, and these cracks decrease the component's mechanical properties and reliability. To overcome this problem, a crack‐healing ability could be a very useful technology. In this study, Al2O3/SiC composite was sintered. This alumina exhibits excellent crack‐healing ability. Small specimens for a bending test were made from the Al2O3/SiC. A semicircular groove was machined using a diamond ball‐drill. The machining reduced the local fracture stress from approximately 820–300 MPa. The machined specimens were crack‐healed under various conditions. The fracture stress of these specimens after crack healing was evaluated systematically from room temperature (RT) to 1573 K. It was found that the local fracture stress of the machined specimen recovered almost completely after crack healing. Therefore, it was concluded that crack healing could be an effective method for improving the structural integrity of machined alumina and reducing machining costs. 相似文献
103.
KYOKO TAKAHASHI CHIKAKO TERADA MISAO TASHIRO TOSHIO ASAO 《Journal of Food Biochemistry》2003,27(5):423-434
Changes in trypsin inhibitory activity and ovomucoid antigenicity in the egg white of Japanese quail egg were observed after subjecting the quail egg to boiling, saúteing and microwave irradiation. Boiling for 10 min caused about 50% loss of the initial trypsin inhibitory activity. With respect to antigenicity, the boiling caused an initial increase followed by a drop to the original level. Saúteing for 3 min resulted in about 90% loss of the inhibitory activity and about 75% loss of the initial antigenicity. Microwave irradiation for 90 s resulted in about 85% loss of the inhibitory activity and about 80% loss of the initial antigenicity. After pepsin digestion of the egg white boiled for 10 min, 100% of the starting trypsin inhibitory activity was retained even after 24 h digestion, while the antigenicity decreased to about 10% of the initial activity. These results suggest that about 50% of the original trypsin inhibitory and 10% of the original antigenic activity remain after a 24 h pepsin digestion of the egg white boiled for 10 min. Thus, we concluded that intact ovomucoid or ovomucoid degradation products with some trypsin inhibitory activity and antigenicity were introduced into the small intestine after ingestion of the cooked egg white of Japanese quail. 相似文献
104.
Ken'ichi Ichihara Chihiro Kohsaka Yoshihiro Yamamoto Takehiro Masumura 《Journal of the American Oil Chemists' Society》2021,98(2):149-155
Free fatty acids (FFA) in crude rice oil were selectively and stoichiometrically derivatized to fatty acid N,N-dimethylamides (FADMA) by catalytic condensation at 45 °C, and then esterified fatty acids (eFA) were directly converted to fatty acid methyl esters (FAME) at 37 °C. The mixture of FADMA and FAME formed in a single test tube was injected into the capillary column of a gas chromatograph (GC). No mutual contamination occurred between FFA and eFA, and reliability of the method was confirmed by comparison between GC data obtained by this method and by a conventional isolation method. The advantages of the present method are that no FFA isolation procedures are required, the reactions proceed under mild temperature conditions, and FFA and eFA can be analyzed simultaneously by GC. 相似文献
105.
M. TAKAHASHI N. OKABE X. ZHU K. KAGAWA 《Fatigue & Fracture of Engineering Materials & Structures》2003,26(5):391-398
ABSTRACT Residual stresses generated by the mismatch of thermal expansion coefficients of ceramics and metals affect the strength of ceramic–metal joints. An interlayer metal can be inserted between the ceramic and metal in order to relax this stress. An analysis was carried out of the residual stresses produced during joint‐cooling and in 4‐point bending tests. The effects of interlayer thickness on ceramic–metal joint strength were then studied by considering a superimposed stress distribution of the residual stress and the bending stress. Finally, joint strength was estimated from fracture mechanics and strength probability analysis by considering the residual stress distribution, defect size and position of pre‐existing defects in the ceramic parts. As a result of this study, we suggest an optimum material selection and interlayer thickness for ceramic–metal joint structures. This approach is generally suitable for the design of electrical and mechanical structures. 相似文献
106.
Hiromu Hashimoto Yasuhiro Ibi Shigeyoshi Kiribe Chihiro Kondou 《Microsystem Technologies》2007,13(8-10):965-971
This paper describes the theoretical modeling for the prediction of slippage onset condition between the paper web and steel roller with experimental verifications. For the first step of modeling, the occurrence of slippage is observed for the cases of uncoated paper (newsprint) and coated paper, and the relation between the slip ratio and roller velocity is measured by changing web tension. Two kinds of theoretical model are proposed, and the applicability of the models is confirmed experimentally. 相似文献
107.
Kinetics of trichloroethene dechlorination with iron powder 总被引:1,自引:0,他引:1
The dechlorination of trichloroethene (TCE) with metallic iron is an advantageous method for the remediation of contaminated groundwater and soil. The toxic reaction intermediates such as dichloroethenes (DCEs) and vinyl chloride (VC), however, occasionally accumulate in the pathway of the reaction. We have been trying to suppress these intermediates by using metallic iron powder containing impurities. In order to investigate the reaction pathways, we measured the production rates of the intermediates and the final products of the dechlorination of TCE such as DCEs, VC, ethyne or ethene. Ethyne, ethene, ethane and cis-DCE were observed as the major products, and trans-DCE, 1,1-DCE, VC, C3-hydrocarbons (such as propane, propylene), C4-hydrocarbons (such as n-butane) and methane were observed as the minors. Also the rate constants of TCE to ethyne and ethyne to ethene were larger than any other constants. These fact show the production of ethene/ethane via ethyne is the main pathway of the dechlorination of TCE using the metallic iron powder. 相似文献
108.
109.
Inter- and/or transgranular crack paths in sintered silicon nitride (Si3N4) during fracture were investigated by in situ straining experiments in a transmission electron microscope at room temperature, using a high-precision micro-indenter. By this technique, cracks introduced in an in situ manner were observed to propagate in the grain interior and along grain boundaries. High-resolution electron microscopy (HREM) observation revealed that the crack propagation takes place at an interface between Si3N4 grains and an intergranular glassy film (IGF) in the case of intergranular fractures. According to the results by previous molecular dynamics simulations, a number of dangling bonds are present at the Si3N4/IGF interface, which should result in the observed fracture behavior at the interface. On the other hand, the crack path introduced during transgranular fracture of Si3N4 grains was found to be sharp and straight. The observed crack propagated towards [1120] inside the Si3N4 grain with the crack surface parallel to the (1100) plane. The HREM observations of crack walls revealed them to be atomically flat. The atomic termination of the crack walls was identified in combination with image simulations based on atomic models of the cleaved crack walls. 相似文献
110.
WATANABE Makoto HATANO Tadashi SAITO Katsuhiko HU Weibing EJIMA Takeo TSURU Toshihide TAKAHASHI Masahiko KIMURA Hiroaki HIRONO Toko WANG Zhangshan CUI Mingqi YAMAMOTO Masaki YANAGIHARA Mihiro 《核技术(英文版)》2008,19(4):193-203
Multilayer polarization elements and their applications to polarimetric studies in 20~400 eV region are mainly reviewed.General principle of selecting material combinations to get high linear polarizance multilayers of reflection type is given with practical examples,with periodic or non-periodic layer structures depending on the usage.Transmission type is introduced as linear polarizer and phase shifter.Their applications include polarization diagnosis of laboratory optical systems and synchrotron radiation beamlines of linear and circular polarization,magnetic rotation experiments such as Faraday rotation and magnetic Kerr rotation on magnetic films and multilayers,and ellipsometry to measure optical constants of thin films precisely.Polarization analysis of soft X-ray fluorescence using multilayer-coated grating is also mentioned.Finally this review is summarized with outlook of further developments. 相似文献