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951.
Y Ikeda T Suehiro M Inoue Y Nakauchi T Morita K Arii H Ito Y Kumon K Hashimoto 《Canadian Metallurgical Quarterly》1998,47(5):598-602
We investigated pressures at 1 cm intervals along the carpal tunnel in 39 patients with carpal tunnel syndrome (CTS) and 12 controls. Pressures were measured for relaxed and gripping hand positions in combination with neutral, extended, and flexed wrist positions. Patient pressures exceeded control pressures, were below the previously reported 30 mmHg threshold for four of five locations in the relaxed neutral position and were typically greater in extension than in flexion. In the neutral position, both patient and control pressures were slightly above threshold levels just distal to the tunnel. Maximum intratunnel pressures were generally found in the central part of the tunnel and minimum pressures in the distal tunnel. Gripping hand pressures in the tunnel were lowest with the wrist flexed. In both controls and CTS patients, only in the neutral wrist and relaxed hand positions were pressures highest at the point where nerve conduction studies have indicated the nerve is most likely to be compromised (in the midpalm just distal to the distal margin of the carpal tunnel). 相似文献
952.
This paper presents a new speed control method for a two-mass system coupled by a flexible shaft. Two control loops are proposed; the outer angular speed control loop calculates the reference signal for the inner loop, where the torsion of the shaft is handled as a variable under control. In this paper, the observer-based discrete-time sliding-mode (ODSM) control implementation and experimental verification of direct torsion control is presented. The experimental system consists of a conventional DC servo gear motor with encoder feedback and inertia load coupled by a flexible shaft. The controller was implemented using a transputer as the computation engine 相似文献
953.
Hashimoto T. Nakasuga Y. Yamada Y. Terui H. Yanagisawa M. Akahori Y. Tohmori Y. Kato K. Suzuki Y. 《Lightwave Technology, Journal of》1998,16(7):1249-1258
A two-step bonding technique for optical device assembly on a planar lightwave circuit platform was developed, which consists of a chip-by-chip thermo-compression prebonding step and a simultaneous reflow bonding step. The technique was used to realize multichip optical integration on the platform. The characteristics of the bonding technique were examined by investigating its strength and accuracy. The bonding accuracies in the horizontal and vertical directions were 1.1 and 0.8 μm, respectively, with high bonding strength. The technique was first applied to a 3 chip integrated transceiver module and the 136 fabricated modules exhibited good performance. The average coupling loss between the laser diodes and the waveguide was estimated to be 4.1 dB and stable characteristics were observed during 1200 cycle thermal shock tests between -40 and 85°C. Next, the two-step bonding technique was used for a 4 channel laser diode module on which 8 optical device chips were integrated and a low coupling loss was achieved of better than 4.2 dB which is as good as that of the 3 chip integrated optical modules 相似文献
954.
M. Hashimoto E. Marui S. Kato 《International Journal of Machine Tools and Manufacture》1996,36(10):1073-1092
A plain milling operation is characterized by a transient and intermittent cutting process, in which undeformed chip thickness varies continuously. The reverse is the case in variations of undeformed chip thickness in the processes of up- and down-milling. In the present study, the property of regenerative chatter vibration in a plain milling operation is investigated from the viewpoint of cutting force variation. With primary chatter vibration, the vibration energy supply is closely related to the collision of the cutting tool flank against the workpiece surface during vibration, which is induced by the bending vibration or the torsional vibration of the arbor. In addition to this factor, the regenerative effect is considered to be one of the main causes of the chatter excitation in regenerative chatter vibration. The simulation result of the cutting force variation during regenerative chatter vibration agrees well with the experimental result, when considering these factors. It is shown that the regenerative chatter vibration in the-down-milling process occurs more easily than in the up-milling process. 相似文献
955.
Takeshi Mizuno Hannes Bleuler Hiroaki Tanaka Hideki Hashimoto Fumio Harashima Hirochika Ueyama 《Electrical Engineering in Japan》1996,117(5):124-133
Active magnetic bearings (AMBs) are applied to turbomolecular pumps (TMPs) and milling spindles. However, their application areas are limited because they are costlier and require larger space than conventional mechanical bearings. Omitting position sensors from AMBs is one of the promising methods to solve such problems. An additional merit is that rotors can be shortened to have a higher critical speed by removing sensor targets from the rotor. The sensorless operation of AMBs has already been achieved in several instruments developed for experimental study. In this research, the sensorless magnetic suspension method is applied to a TMP manufactured as an industrial product, and it is demonstrated that sensorless AMBs can suspend a high-speed rotor. 相似文献
956.
T Ogura M Takaoka T Yamauchi T Oishi Y Mimura M Hashimoto N Asano M Yamamura F Otsuka H Makino Z Ota K Takahashi 《Canadian Metallurgical Quarterly》1996,27(1-2):41-55
To elucidate the renal injury induced by gold treatment, we administered various doses of gold sodium thiomalate (GST) to Wistar rats and investigated alterations in the urinary enzyme activity, gamma-glutamyl transpeptidase (gamma GTP) and N-acetyl-beta-glucosaminidase (NAG) activity, and histochemical change of enzymes, gamma GTP, alkaline phosphatase (ALP) and acid phosphatase (ACP) activity in the renal tissue. The single administration of a large dose of gold salts induced acute tubular necrosis and enzyme leakage was detected histochemically without damage to the glomerulus. After chronic administration of small doses of gold salts, the urinary gamma GTP activities gradually increased, but urinary NAG activities did not. These findings suggested that the change in urinary enzyme activities, which leaked from inside of brushborder or lysosome, indicated the degree or localization of tubular damage, because renal tubules were selectively injured by gold salts. 相似文献
957.
958.
T. Sakaki G. J. Weng K. Kakehi S. Hashimoto 《Metallurgical and Materials Transactions A》1996,27(2):317-326
A continuum mechanics model has been developed on the basis of Hill's theory of orthogonal anisotropy for predicting global
mechanical properties of sheets with a through-thickness texture gradient and strength gradient. By the present model, the
globalr value and yield and flow stresses of the entire sheet can be predicted from the local anisotropic parameters, yield and flow
stresses which are given as arbitrary functions of the through-thickness position of the sheet. 相似文献
959.
S Kawana T Hashimoto T Nishikawa S Nishiyama 《Canadian Metallurgical Quarterly》1994,130(12):1534-1538
BACKGROUND AND DESIGN: Several articles have described patients with pemphigus who showed a transition from pemphigus vulgaris (PV) to pemphigus foliaceus (PF) or vice versa. However, there have been no adequate reports in the literature on the association between transition in disease type and change in autoantibody reactivity against the pemphigus antigens. We investigated the antigen profiles of the serum samples obtained from two patients with pemphigus who were demonstrated to shift from PV to PF with evidence from clinical, histologic, and immunohistologic findings. Western blot technique was performed using normal human epidermal extracts as an antigen source. RESULTS: The serum samples of both cases at the PV stage reacted with the 130-kd antigen and the serum samples at the PF stage reacted with the 150-kd antigen. Accordingly, the dermatologic, histologic, and immunohistologic findings before and after the transition from PV to PF were clearly related to changes in the serum reactivity with the pemphigus antigens. CONCLUSIONS: This was the first investigation completely demonstrating changes in antigen profiles at the molecular level consistent with transition from the PV to the PF form of the disease. Moreover, the findings of this study confirmed the existence of a close correlation between the 130- and the 150-kd antigens, with the onset of each form of the disease. 相似文献
960.
LL Jiang A Kobayashi H Matsuura H Fukushima T Hashimoto 《Canadian Metallurgical Quarterly》1996,120(3):624-632
Human medium-chain enoyl-CoA hydratase was purified from liver, because we noticed the presence of a high medium-chain enoyl-CoA hydratase activity in human skin fibroblasts catalyzed by an enzyme different from the known enzymes catalyzing the enoyl-CoA hydratase reaction. Two enzyme preparations were obtained. One of them, preparation I, consisted of 46-kDa polypeptide, and its molecular mass was estimated to be 86 kDa. The other, preparation II, consisted of a major 77-kDa polypeptide and minor smaller polypeptides including 46-kDa polypeptide. The molecular mass of preparation II was 154 kDa. Both enzyme preparations catalyzed reversible dehydration of medium-chain D-3-hydroxyacyl-CoA to 2-trans-enoyl-CoA, but did not react with L-3-hydroxyacyl-CoA. Catalytic properties and immunochemical reactivities of these enzyme preparations were nearly the same. The cross-reactive material to the antibody was confirmed to be in peroxisomes by immunohistochemical study of cultured human skin fibroblasts. 相似文献