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41.
Combined tension and torsion experiments with thin wall specimens of Cu-Al-Zn-Mn polycrystalline shape memory alloy (SMA) were performed at temperatureT =A f + 25 K. The general stress-strain behaviors due to the thermoelastic martensitic transformation, induced by a combination of external forces of axial load and torque, were studied. It is shown that the progress of martensitic transformation (MT) at general stress conditions can be well considered as triggered and controlled by the supplied mechanical work (a kind of equivalent stress) in the first approximation. Pseudoelastic strains in proportional as well as nonproportional combined tension-torsion loadings were found fully reversible, provided that uniaxial strains were reversible. The axial strain can be controlled by the change of torque andvice versa due to the coupling among tension and torsion under stress, not only in forward transformation, but also in reverse transformation on unloading. The pseudoelastic strains of SMA polycrystal are path dependent but well reproducible along the same stress path. The evolution of macroscopic strain response of SMA polycrystal, subjected to the nonproportional pseudoelastic loading cycles with imposed stress path, was systematically investigated. The results bring qualitatively new information about the progress of the MT in SMA polycrystal, subjected to the general variations of external stress. PETR SITTNER, Research Associate, formerly with the Faculty of Engineering, Mie University  相似文献   
42.
Bioassays were performed on malePeriplaneta americana L. using synthetic (–)-periplanone-B (P-B) and Hauptmann's (–)-periplanone-A (P-A), and their mixtures at various ratios to estimate the roles of both periplanones for the sexual communication of the species. Both P-A and P-B elicited qualitatively the same responses, such as antennal movement, rapid locomotion, wing raising, and homosexual behavior of male cockroaches, but the threshold of the pheromone activities for P-B was two orders of magnitude lower than that of P-A. Neither synergistic nor inhibitory but only a simple integrated effect on the responses was observed when mixtures of P-A and P-B were applied.  相似文献   
43.
Four coals with similar ultimate analyses were Soxhlet-extracted with pyridine before and after heat treatment at 400 °C and with quinoline at 350 °C. Pyridine extraction yield tended to be proportional to log maximum fluidity (MF), but with some discrepancies. Quinoline extraction yield was more nearly proportional to log MF. However, the best correlation with log MF was obtained for quinoline extraction yield corrected for inert content.  相似文献   
44.
A method of developing strategic CIM is described. Relationship between CIM and firm's competitive power is clarified, and a fundamental planning procedure for CIM is developed for enhancing the competitiveness. In the procedure, the system configuration of CIM is analyzed using 0–1 goal programming techniques. A numerical example is also demonstrated to show the effectiveness of the procedure.  相似文献   
45.
Methanol, ethanol, straight-chain propanol, isopropanol, straight-chain butanol, sec-butanol, tert-butanol, straight-chain pentanol, and iso-pentanol were used for the reaction of coal with NaOH-alcohol at 290 °C for 1 h. All the products dissolved in pyridine with an extraction yield > 80 wt%. Straight-chain alcohols are less reactive than the secondary alcohols owing to the differences in hydrogen donating ability.  相似文献   
46.
NitrogenDopingEfectinaGe:HFilmsDueToHighHydrogenDilutionJ.Xu1K.J.Chen1D.Feng1,SeichiMiyazaki2MasatakaHirose2(1.Dept.ofPhysic...  相似文献   
47.
Using the values of the rotational molecular parameters (including cencrifugal distortion terms) of the H2 16O molecule, which can explain 12 observed transitions below 800 GHz, all rotational energy levels with normalized Boltzmann factors larger than 5×10?8 at 300°K are calculated. Probabilities of all possible electric dipole transitions among these states, 2277 lines, are calculated using the eigenfunctions thus obtained, and the permanent electric dipole moment of 1.8546 Debye. Assuming the single and full Lorentzian line forms, we calculated the absorption coefficient for millimeter to submillimeter region. Our result, using the single term Lorentzian line form, agrees quite well with experiment for 1 Torr of water vapor in 760 Torr air at 300°K.  相似文献   
48.
Low-noise amplifiers for u.h.f. colour t.v. broadcasting translator use have been successfully developed by using 1 ?m gate GaAs m.e.s.f.e.t.s. The obtained performances revealed that a GaAs m.e.s.f.e.t. has low-noise and low intermodulation distortion characteristics, even in the 500?800 MHz frequency range, compared with a Si bipolar transistor.  相似文献   
49.
This paper describes a musical instrument identification method that takes into consideration the pitch dependency of timbres of musical instruments. The difficulty in musical instrument identification resides in the pitch dependency of musical instrument sounds, that is, acoustic features of most musical instruments vary according to the pitch (fundamental frequency, F0). To cope with this difficulty, we propose an F0-dependent multivariate normal distribution, where each element of the mean vector is represented by a function of F0. Our method first extracts 129 features (e.g., the spectral centroid, the gradient of the straight line approximating the power envelope) from a musical instrument sound and then reduces the dimensionality of the feature space into 18 dimension. In the 18-dimensional feature space, it calculates an F0-dependent mean function and an F0-normalized covariance, and finally applies the Bayes decision rule. Experimental results of identifying 6,247 solo tones of 19 musical instruments shows that the proposed method improved the recognition rate from 75.73% to 79.73%. This research was partially supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Grant-in-Aid for Scientific Research (A), No.15200015, and Informatics Research Center for Development of Knowledge Society Infrastructure (COE program of MEXT, Japan). Tetsuro Kitahara received the B.S. from Tokyo University of Science in 2002 and the M.S. from Kyoto University in 2004. He is currently a Ph.D. course student at Graduate School of Informatics, Kyoto University. Since 2005, he has been a Research Fellow of the Japan Society for the Promotion of Science. His research interests include music informatics. He recieved IPSJ 65th National Convention Student Award in 2003, IPSJ 66th National Convention Student Award and TELECOM System Technology Award for Student in 2004, and IPSJ 67th National Convention Best Paper Award for Young Researcher in 2005. He is a student member of IPSJ, IEICE, JSAI, ASJ, and JSMPC. Masataka Goto received his Doctor of Engineering degree in Electronics, Information and Communication Engineering from Waseda University, Japan, in 1998. He then joined the Electrotechnical Laboratory (ETL; reorganized as the National Institute of Advanced Industrial Science and Technology (AIST) in 2001), where he has been engaged as a researcher ever since. He served concurrently as a researcher in Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Corporation (JST) from 2000 to 2003, and an associate professor of the Department of Intelligent Interaction Technologies, Graduate School of Systems and Information Engineering, University of Tsukuba since 2005. His research interests include music information processing and spoken language processing. Dr. Goto received seventeen awards including the IPSJ Best Paper Award and IPSJ Yamashita SIG Research Awards (MUS and SLP) from the Information Processing Society of Japan (IPSJ), Awaya Prize for Outstanding Presentation and Award for Outstanding Poster Presentation from the Acoustical Society of Japan (ASJ), Award for Best Presentation from the Japanese Society for Music Perception and Cognition (JSMPC), WISS 2000 Best Paper Award and Best Presentation Award, and Interaction 2003 Best Paper Award. He is a member of the IPSJ, ASJ, JSMPC, Institute of Electronics, Information and Communication Engineers (IEICE), and International Speech Communication Association (ISCA). Hiroshi G. Okuno received the B.A. and Ph.D from the University of Tokyo in 1972 and 1996, respectively. He worked for Nippon Telegraph and Telephone, Kitano Symbiotic Systems Project, and Tokyo University of Science. He is currently a professor at the Department of Intelligence Technology and Science, Graduate School of Informatics, Kyoto University. He was a visiting scholar at Stanford University, and a visiting associate professor at the University of Tokyo. He has done research in programming languages, parallel processing, and reasoning mechanism in AI, and he is currently engaged in computational auditory scene analysis, music scene analysis and robot audition. He received the best paper awards from the Japanese Society for Artificial Intelligence and the International Society for Applied Intelligence, in 1991 and 2001, respectively. He edited with David Rosenthal “Computational Auditory Scene Analysis” from Lawrence Erlbaum Associates in 1998 and with Taiichi Yuasa “Advanced Lisp Technology” from Taylor and Francis Inc. in 2002. He is a member of IPSJ, JSAI, JSSST, JSCS, ACM, AAAI, ASA, and IEEE.  相似文献   
50.
The contents of nitrate and nitrite in vegetable juice (n = 63), tea beverage (n = 12) and mineral water (n = 15) were measured. The mean contents of nitrate were 0.73 +/- 14.57 mg/100 g, 0.61 +/- 1.12 mg/100 g and 0.25 +/- 0.33 mg/100 g as NO3-, respectively. The contents of the nitrite were 0.03 +/- 0.05 mg/100 g, 0.02 +/- 0.01 mg/100 g and 0.001 +/- 0.001 mg/100 g as NO2-, respectively. The content of nitrate is high in some vegetable juices, and warnings may be necessary for people who drink them frequently.  相似文献   
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