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31.
Numerical simulations have been carried out for two-dimensional wavy falling liquid film in order to investigatekinetic energy and surface energy of that liquid film.Governing equations,which are continuity equation,Na-vier-Stokes equation,and equations of interfacial boundary conditions including surface movement and effect ofsurface tension,have been solved directly by means of a numerical scheme based on the finite difference method.In most cases,periodic disturbances superimposed at inflow boundary grow to fully developed waves which re-tain the given periodic behavior.In some cases,however,random waves appear after the fully developed waves.Variations of kinetic energy and surface energy of the periodically developed waves and the random waves havebeen discussed. 相似文献
32.
Toshihisa Nishioka Masaki Nishi Takehiro Fujimoto Keigo Sakakura Jonathan S. Epstein 《International Journal of Pressure Vessels and Piping》1995,63(3):261-275
Moiré interferometry was used for direct measurements of the crack tip behavior in the homogeneous compact tension (CT) specimens of A533B and HT80 steels, and in electron-beam welded inhomogeneous CT specimens of the two materials. These two materials have considerably different yield stresses, although their elastic properties are the same. Five types of homogeneous and inhomogeneous specimens were used in the experiment. Moiré fringe patterns of the five specimen types were directly compared for elastic, elastic-plastic and unloaded stages. Although the global deformations in terms of the load versus COD relations exhibit little inhomogeneity effects, large inhomogeneity effects were observed in the moiré fringe patterns in the elastic-plastic and unloaded stages. The near-tip deformations were also compared with the corresponding HRR singular fields. In a horizontal weld specimen, due to strong hardening in the weld region, the slope of the displacement field does not shift the characteristic HRR field for the A533B or the HT80 steel for increasing load. 相似文献
33.
M Sato A Sakurada M Sagawa C Endo T Tanita T Kondo E Tsuchiya S Fujimura A Horii 《Canadian Metallurgical Quarterly》1998,23(4):367-370
This study was undertaken to determine whether melatonin (N-acetyl-5 methoxytryptamine) is effective in helping emergency medical services (EMS) personnel who work rotating night shifts reset their biological clocks and minimize circadian rhythm disruption. A double-blinded, randomized, crossover study was performed using 22 volunteers. Participants were working a span of consecutive night (2300 to 0700 hours) shifts and received either a melatonin capsule (6 mg) or placebo to be taken before each of the consecutive day sleeps. Each participant completed a total of 4 spans of consecutive night shifts (2 melatonin, 2 placebo). Collected data included daily sleep diaries, quantification of alcohol/caffeine consumed, and drug side effects. Assessment of sleep quality, posttreatment mood, and workload ratings were measured daily by 10-cm visual analog scale (VAS). Analysis of sleep diaries found no significant difference (P > .05) between the two treatments with respect to mean sleep latency, duration, and efficiency, and subjectively rated sleep quality. Similarly, no significant benefits were noted between the median VAS scores for daily posttreatment mood or workload ratings. Adverse effects were rare; one patient taking melatonin reported a prolonged sedative effect. Despite recent interest in melatonin for treatment of circadian-based sleep disorders, no clinical benefits were noted in EMS personnel working rotating night shifts. 相似文献
34.
E Inooka S Umeda Y Kutsuwa T Takahashi K Sagawa T Takahashi H Inooka 《Canadian Metallurgical Quarterly》1998,21(12):893-898
BACKGROUND: Heart failure has been evaluated by several methods, the New York Heart Association (NYHA) classification of heart failure based on symptoms being used most frequently. However, the degree of heart failure assessed by these criteria does not always correlate with cardiac function in daily life. HYPOTHESIS: The aim of the study was to evaluate cardiac function based on the walking pace/heart rate (HR) relationship to assess the effects of enalapril, an angiotensin-converting enzyme inhibitor, in patients with mild to moderate cardiac function. METHODS: To evaluate cardiac function objectively, we developed a method using a pedometer to count the steps walked while simultaneously recording HR using a Holter electrocardiograph (ECG). Step-count walk rate (WR) was recorded on the magnetic tape of the Holter apparatus, and both HR and walking pace were calculated automatically by the Holter ECG analysis system. Data were determined every hour, and mean pace and HR were plotted along the x and y axes, respectively. The slope of HR x WR was calculated using the least squares method. The slope and the total number of steps were regarded as indicators of cardiac function and quality of life, respectively. We analyzed 36 subjects, consisting of 8 normal volunteers, 8 patients in New York Heart Association (NYHA) class I. 11 in class II, and 9 in class III chronic mild heart failure, during maximal exercise work load by bicycle ergometer; furthermore, fractional shortening of the left ventricle on echocardiogram was determined in 14 patients with chronic mild heart failure and was compared with the slope of HR x WR. Enalapril was administered at a daily dose of 2.5-10 mg for 1-24 months (mean 6 months) in 60 patients to evaluate the effects of this drug on these parameters. RESULTS: There was a significant inverse relationship between maximal work load and the HR x WR slope, and also between the fractional shortening and the slope, suggesting that the slope may reflect the severity of cardiac dysfunction. Furthermore, the slope decreased significantly from 1.8 +/- 1.26 before enalapril to 1.0 +/- 0.94 (mean +/- standard deviation) after drug administration, while the total number of steps increased significantly from 4842 +/- 3581 to 7804 +/- 4793. CONCLUSION: The slope of the graph relating step count and HR proved to be a good, objective indicator of cardiac function, and enalapril therapy improved this parameter. 相似文献
35.
36.
Hitoshi Kakimoto Takehiro Hayashi Hirosi Handa Kenzi Yukihira Yukio Okamura Naotaka Odaka 《Electrical Engineering in Japan》1995,115(5):75-87
This paper describes the development of the Automatic Fault Point Locating and Sectional Isolating System. This system locates a single-line-to-ground fault point at each pole by using ground-current sensors, and isolates the faulted section by controlling pole switches with no outage of unfaulted sections. The ground-current sensor is connected to the line between allied ground terminals of pole devices and grounded conductor. It detects a ground fault current of more than 0.64 amperes that is determined so as to avoid an unexpected operation by stray current, but to detect the fault current accurately, and sends out an emergency signal with time delay of 0.1 s. Sectional isolation starts when both the emergency signal from the sensor and relay operation signals from a substation are received and ends within a feeder circuit-breaker tripping time of 1.5 s. 相似文献
37.
38.
Toyonaka T. Sagawa M. Hiramoto K. Shinoda K. Uomi K. Ohishi A. 《Electronics letters》1995,31(3):198-199
Highly reliable operation of 0.98 μm strain-compensated InGaAs/ InGaAsP lasers is demonstrated for the first time with an estimated lifetime of 170 kh at 25°C. Moreover, we reveal that the degradation rates at 90°C and 80 mW output power are four times smaller than those of identical lasers with GaAs barriers 相似文献
39.
T Sagawa H Negishi T Kishida H Yamada S Fujimoto 《Canadian Metallurgical Quarterly》1995,70(6):839-846
The purpose of our study is to see whether vaginal and cervical pH are helpful to screen for bacterial vaginosis and cervicitis during pregnancy. One hundred and seven pregnant women underwent prospectively both vaginal pH and cervical pH measurement and screening for microbial infections of the lower genital tracts at 10, 20 and 30 gestational week between February 1993 and August 1993. The value of vaginal pH significantly elevated in bacterial vaginosis (P < 0.05). Vaginal pH values also significantly elevated in patients who had had sexual intercourse 2 days before the dates of examinations (P < 0.01). Cervical pH value exhibited no significant change in bacterial vaginosis and cervicitis. Vaginal pH is a valid indicator for screening of bacterial vaginosis during pregnancy. However, vaginal pH might be influenced by the presence of semen. Cervical pH is not a useful parameter for screening of cervicitis during pregnancy. 相似文献
40.