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排序方式: 共有1197条查询结果,搜索用时 31 毫秒
131.
Nobuaki Kamimoto Yutaka Yamada Masami Kitamura Kiyoshi Nishikawa 《Artificial Life and Robotics》2005,9(1):7-11
We propose a method of evaluating the vibration of motor-operated electric tools (MOETs) by using a self-organizing feature map (SOM). The vibration spectrum is used to evaluate the MOET vibration. These vibration spectra are derived from 18 vibration data obtained by measurements on three different positions of a MOET. The spectra are then sent to the SOM network for the calculations. The vibration spectra are classified by the SOM, and calculations give the Euclidean distance from the weight vector in order to develop a quantitative evaluation. A statistic analysis of the Euclidean distance allows a quantitative evaluation of a MOET with respect to vibration stress and other relevant parameters.This work was presented, in part, at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30, 2004 相似文献
132.
K. Mitsui T. Aoki A. Okada Y. Ohashi Y. Muraki S. Shibata I. Nakamura H. Kojima T. Kitamura Y. Minorikawa Y. Kato T. Takahashi S. Higashi K. Kobayakawa Y. Kamiya 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1990,290(2-3):565-578
Accurate measurements of the total number of muons in an air shower are important for the discrimination of showers produced by astronomical gamma rays from those produced by protons. In order to perform this discrimination, muon detectors with a total area of about 400 m2 have been constructed in the Ohya stone mine. At ground level, scintillation detectors have been distributed for determining the total number of electrons in the air shower. The arrival direction of the air shower determined by usual timing information was examined using independent data on the arrival direction determined by muons in the shower. The angular resolution thus obtained at the shower maximum is 1.7° in the south-north plane and 2° in the east-west plane. The difference of the resolution is due to the asymmetric arrangement of scintillation detectors. 相似文献
133.
H Iso T Shimamoto Y Naito S Sato A Kitamura M Iida M Konishi DR Jacobs Y Komachi 《Canadian Metallurgical Quarterly》1998,29(8):1510-1518
BACKGROUND AND PURPOSE: Although randomized clinical trials have demonstrated the benefit of antihypertensive treatment in preventing stroke, the effectiveness of community-based programs is largely unknown. We investigated long-term community-based prevention activities. METHODS: In rural northeastern Japan, people aged > or = 30 years numbered 3219 in the full intervention community and 1468 in the minimal intervention community in 1965. Systematic blood pressure screening and health education began in 1963. Stroke was registered through 1987. RESULTS: More than 80% of people aged 40 to 69 years were screened in both communities in the 1960s. One community charged for screening services after 1968, whereas the other community intensified intervention; subsequently, screening rates and the follow-up of hypertensive individuals declined in the minimal intervention community, especially in men. In men, stroke incidence declined more (P < 0.001) in the full intervention (42% in the period 1970 to 1975, 53% in the period 1976 to 1981, and 75% in the period 1982 to 1987) than in the minimal intervention community (5% increase, 20% decrease, and 29% decrease, respectively); in women, the stroke incidence declined about 45% to 65% in both communities. Changes in stroke prevalence paralleled those in stroke incidence. Trends in systolic blood pressure levels tend to explain the differential stroke rates in men. CONCLUSIONS: Delivery of hypertension control services through intensive, free, community-wide screening and health education was effective in prevention of stroke for men in a community. 相似文献
134.
Three male patients, aged 43, 41 and 44 years, were referred to the cardiologist because of complaints of angina pectoris; one of them also had an aortic valve stenosis. Nine to 22 years before, they had received radiotherapy on the mediastinum because of Hodgkin's disease. Coronary angiography showed severe stenoses of the ostium of the right coronary artery or of the main left coronary artery, following which the patients were treated with coronary artery bypass surgery, aortic valve replacement and (or) drugs. These locations are very unusual in patients with angina who did not receive any radiation therapy, but they are seen frequently in patients who have received radiotherapy on the mediastinum. The pathogenesis of these lesions is not exactly known. The normal risk factors for atherosclerosis plus free oxygen radicals are probably involved. The free oxygen radicals, generated by radiation, locally activate coagulation via various hypothetical mechanisms. The damaging effect of radiotherapy could therefore be prevented by antioxidants. However, the therapeutic effect of radiation would most likely decrease as well. A more rational approach to prevent these vascular lesions would be to reduce the radiation load, to treat the risk factors for atherosclerosis and to give platelet aggregation inhibitors such as acetylsalicylic acid. 相似文献
135.
136.
S Morimoto A Hirano T Ohkawa J Doi A Suzuki K Hagino S Kitamura Y Sawada T Morita Y Miyazaki 《Canadian Metallurgical Quarterly》1995,41(4):245-251
One hundred and sixty one patients with upper urinary stones were examined for antimicrobial prophylaxis following extracorporeal shock wave lithotripsy (ESWL). They were divided into two groups, the low-risk group (n = 133) and high-risk group (n = 28), according to the risk factors of urinary tract infection. The patients in the low-risk group were further randomized into two groups which were orally given ofloxacin for 7 days after ESWL (Group A, n = 66), no antimicrobial (Group B, n = 67). The patients in the high-risk group were randomly subdivided into three groups which were given flomoxef intravenously for 2 or 3 days and ofloxacin for 4 or 5 days thereafter (Group C, n = 10), flomoxef only for 2 or 3 days and no drugs later (Group D, n = 10), ofloxacin for 7 days (Group E, n = 8). In all of the patients in the low-risk group, during the 7 days after ESWL, fever elevation was observed in only 1.5% of patients, and bacteriuria in 10.0% on the 7th day. There was no difference in frequency of fever elevation and bacteriuria following ESWL between Group A and Group B. These findings indicate that prophylactic antimicrobial after ESWL treatment is not necessary for low risk patients with urinary tract infections. In the high-risk group, the over-all rates of fever elevation and bacteriuria were 21.4% and 24.0% respectively. The difference of effectiveness among the prophylactic regimens of the three groups (Group C, D, E) was not shown.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
137.
Creep cavity growth under interaction between lattice diffusion and grain-boundary diffusion 总被引:1,自引:0,他引:1
Tadahiro Shibutani Takayuki Kitamura Ryuichi Ohtani 《Metallurgical and Materials Transactions A》1998,29(10):2533-2542
A model and a method of numerical analysis of the cavity growth in grain boundaries in metals due to lattice diffusion are
proposed. The growth behavior simulated is compared to that due to grain-boundary (GB) diffusion. The simulation method is
extended to analyze the growth under the interaction between lattice diffusion and GB diffusion. The growth rate calculated
under the interaction is approximately equal to the linear sum of those due to the pure lattice diffusion and the pure GB
diffusion. 相似文献
138.
Y Murakami Y Ishinaga K Sano R Murakami Y Kinoshita J Kitamura K Kobayashi S Okada K Matsubara T Shimada S Morioka 《Canadian Metallurgical Quarterly》1996,19(6):473-476
BACKGROUND: Platelet activation and coagulation abnormality have been observed during coronary spasm. It is crucial whether platelet activation occurs even during a nonischemic period. HYPOTHESIS: This study was designed to determine whether platelets might be activated across the coronary bed during a nonischemic interval in patients with vasospastic angina. METHODS: Plasma levels of serotonin, 6-keto-prostaglandin F1 alpha, and catecholamines in the aorta and the coronary sinus were simultaneously measured in 16 patients with vasospastic angina and 13 control patients with nonischemic heart disease. RESULTS: None of these patients showed myocardial ischemia during sampling. The difference in transcardiac plasma levels of serotonin in patients with vasospastic angina was significantly higher than that in controls (1.48 +/- 1.08 ng/ml vs. 0.07 +/- 0.12 ng/ml, respectively, p < 0.001). Coronary sinus plasma norepinephrine levels in these two groups were almost the same (204.8 +/- 110.8 pg/ml vs. 190.4 +/- 131.6 pg/ml, respectively). The ratio of 6-keto-prostaglandin F1 alpha in the coronary sinus and the aorta was not different between the two groups (1.17 +/- 0.96 in patients with vasospastic angina vs. 1.15 +/- 0.68 in controls). CONCLUSIONS: These data suggest that platelet activation across the coronary bed should be ascribed to endothelial dysfunction. Lack of compensatory enhancement of prostacyclin production might be concerned with dysfunction of coronary endothelial cells in these patients. 相似文献
139.
140.
M. Kitamura H. Yamazaki T. Sasaki N. Kida I. Mito 《Photonics Technology Letters, IEEE》1991,3(4):305-307
Long cavity (1200 mu m) MQW-DFB-DC-PBH-LDs have been developed. The devices simultaneously showed less than 1 MHz spectral linewidth, lower than 15 kHz FM dip frequency, moderate FM efficiency (250-300 MHz/mA at 100 MHz modulation frequency), as well as 10-GHz FM bandwidth (6 dB down level from the peak), at 30 mW output power condition. Such LDs will be suitable for Gb/s continuous phase frequency shift keying (CPFSK) current optical fiber communication systems.<> 相似文献