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1.
In a bending load test for brittle materials, such as ceramics for spacecraft and aircraft, decreasing the number of test specimens required is a crucial problem. This paper discusses the effectiveness of using the information of both fracture stress and fracture location to decrease the number of specimens required to obtain the same precision as the Weibull estimator. The following results were obtained: It was found that by adding the fracture location information, the precision of the Weibull parameter estimation under the optimal design became 1.5–1.9 times better compared with the case of using only the fracture stresses. This means the number of samples necessary to attain the same precision becomes 1/1.5–1/1.9. Tables and figures which give information on the number of samples necessary to attain the required precision are given. 相似文献
2.
S. Matsuo Y. Mizuguchi Y. Tanaka H. Kubota R. Yamamoto 《International Journal of Thermophysics》1996,17(2):441-454
Densities of aqueous of 1,4-dioxane have been measured at temperatures from 298 to 348 K and at pressures up to 40 MPa by a vibrating-tube method. Molar volumes obtained with an estimated uncertainty of ±0.2°,% are correlated with pressure by the Tait equation within the experimental uncertainty. Pressure and composition dependences of the excess molar volume, partial molar volume, and isothermal compressibility are determined and they are compared with those of other aqueous solutions. 相似文献
3.
4.
K Maekawa H Ohnishi T Hirase T Yamada T Matsuo 《Canadian Metallurgical Quarterly》1994,235(5):489-492
A 33-year-old pregnant woman suffered from acute anteroseptal myocardial infarction at the 19th gestational week. Despite periodic attacks of myocardial ischaemia after admission, the coronary arteriograms under the use of nitroglycerin were normal. Thereafter, she remained free from the ischaemic events with diltiazem hydrochloride and delivered a healthy baby. The coronary arteriography at puerperium also showed no organic narrowing. However, the provocative test with acetylcholine chloride caused severe spasm of the left anterior descending coronary artery. These findings strongly suggest that acute myocardial infarction in this pregnant woman was caused by coronary artery spasm. 相似文献
5.
H Matsubara N Oya Y Suzuki S Kajiura K Suzumori Y Matsuo T Suzuki T Hashimoto 《Canadian Metallurgical Quarterly》1997,12(5):306-308
Both choledochal cyst and congenital biliary atresia (type I cyst) may share the same ultrasonographic pattern. We report 2 cases which were shown to have cystic structures on the upper abdomen by antenatal ultrasonography. The size of the choledochal cyst found at 24 weeks' gestation increased steadily as gestational age advanced. But the size of the cyst in congenital biliary atresia found at 29 weeks' gestation remained unchanged throughout the remaining pregnancy. Cyst enlargement, therefore, may suggest the possibility of a choledochal cyst. 相似文献
6.
Matsuo N. Matsui H. Tokunaga Y. 《Selected Areas in Communications, IEEE Journal on》1991,9(4):548-554
People faced with an unfamiliar product or service tend to fall back on mental models based on analogical relationships with familiar products or services. Two experiments on the analogical relationships or metaphors that people might use when operating a communications terminal are described. In the first experiment, the role previously acquired operating knowledge has in determining the mental models people use when directory dialing with novel equipment is examined. In a second experiment, it is shown that an explicit appeal to an analogy between conventional mail and electronic mail can help users learn to use an electronic mail system, and make it easier for them to remember how to use the system as long as 90 days after initial exposure. It is concluded that the mental model is constructed only from the user's operating knowledge acquired as a result of past experiences, and the metaphor method is effective when the instructions are metaphorically taught 相似文献
7.
Yamada T. Nakata Y. Hasegawa J. Amano N. Shibayama A. Sasago M. Matsuo N. Yabu T. Matsumoto S. Okada S. Inoue M. 《Solid-State Circuits, IEEE Journal of》1991,26(11):1506-1510
A 64-Mb dynamic RAM (DRAM) has been developed with a meshed power line (MPL) and a quasi-distributed sense-amplifier driver (qDSAD) scheme. It realizes high speed, t RAS=50 ns (typical) at V cc=3.3 V, and 16-b input/output (I/O). This MPL+qDSAD scheme can reduce sensing delay caused by the metal layer resistance. Furthermore, to suppress crosstalk noise, a V SS shield peripheral layout scheme has been introduced, which also widens power line widths. This 64-Mb DRAM was fabricated with 0.4-μm CMOS technology using KrF excimer laser lithography. A newly developed memory cell structure, the tunnel-shaped stacked-capacitor cell (TSSC), was adapted to this 64-Mb DRAM 相似文献
8.
Takada T. Oto T. Kitagaki K. Hatanaka N. Demura T. Fuji H. Odaka T. Sue H. Oku T. 《Solid-State Circuits, IEEE Journal of》1989,24(6):1656-1661
A video codec LSI for high-definition television (HDTV) systems has been developed. By using a time-compressed integration encoding technique, it converts a 20.0-MHz bandwidth luminance signal and two 5.0-MHz chrominance signals into a compressed image signal at 48.6-MHz sampling frequency. It is useful in many HDTV application systems, such as 400-Mb/s digital transmission system, a video disk player system, or an analog transmission system. Over 288000 elements, including a 52-kb one-transistor DRAM (dynamic random access memory) line memory specially developed for this LSI, were integrated on a 12.16×12.10-mm2 chip. A standard cell layout method and a 1.2-μm CMOS logic LSI process were used 相似文献
9.
Within the context of an extensive study of electroconvulsive therapy at the Psychiatric Clinic of the University of Bonn 15 patients suffering from therapy-resistant Major depression (DSM III-R) were examined with a detailed psychometric test battery, containing memory- and nonmemory tests. The test battery had been applied short time before, during and after the treatment with 10 ECT applied unilateral over the nondominant hemisphere. Comparing the test performances before and 1-2 days after the end of the series there were only few remarkable changes: a significant decrease was diagnosed exclusively in 30 min delayed recall of verbal items, while visual short-term memory and visual-constructive performance showed a significant improvement (in spite of unilateral stimulation on the right side). None of the other cognitive functions inclusively speed of performances and reaction time was detracted short time after the end of the ECT-treatment, instead all the measures improved albeit not significantly. Between responders to treatment (50% improvement in HAMD) and non-responders no significant differences neither before nor after the treatment were detected. The non-responders had in nearly all of the tests some better (but not significantly) results despite being older than the group of responders. 相似文献
10.
This paper describes a flexible random allocation program that assigns treatments to patients according to their prognostic factors in multi-institutional clinical trials. The source lists are available in the appendix of this paper. This program is based on Pocock and Simon's minimization method and Zelen's method for institution balancing. The numbers of institutions, treatments, and prognostic factors can be set arbitrarily. The maximum number of institutions, treatments, or prognostic factors that can be accommodated by the program is limited only by the size of the main memory. For example, an IBM-PC with a 640KB main memory can run a program of 1500 institutions, 4 treatments and 20 prognostic factors. 相似文献