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101.
Prof. Dr.-Ing. G. Gerber 《Electrical Engineering (Archiv fur Elektrotechnik)》1975,57(3):127-131
Übersicht Die Ersatzbilder üblicher Nutenleiter werden angegeben, ihre Glieder werden beschrieben und die mathematischen Funktionen, insbesondere die Kombinationen der in den Gliedern auftretenden Besselschen und Hankelschen Funktionen, werden in der Gaußschen Zahlenebene bzw. in der konjugierten Gaußschen Zahlenebene graphisch dargestellt.Die Kurvenzüge bestätigen, daß bei geschichteten Leitern der Einfluß der obersten Schicht auf die Gesamtimpedanz um so größer wird, je größer dessen reduzierte Leiterhöhe ist.
Contents The equivalent circuits of standard slot conductors of electrical machines are given, their elements are described, and the mathematical functions, especially the combination of the Bessel and Hankel functions that occur in the elements, are represented graphically in the gauss-plane or in the conjugate gauss-plane, respectively.The curves confirm that in layered conductors the effect of the uppermost layer on the total impedance increases according to the size of its reduced conductor height.相似文献
102.
103.
VD Tsu 《Canadian Metallurgical Quarterly》1993,100(4):327-333
OBJECTIVES: To identify risk factors associated with postpartum haemorrhage (PPH) in order to improve the effectiveness of antenatal screening. DESIGN: A population-based case control study. SETTING: Harare, Zimbabwe. SUBJECTS: Two groups of women, one group consisting of those with postpartum haemorrhage after a normal vaginal delivery and the other of women with normal unassisted vaginal delivery without PPH. METHOD: Data abstracted from the medical records; relative risks were estimated by multivariate logistic regression. RESULTS: Low parity, advanced maternal age, and antenatal hospitalisation were among the strongest risk factors, with more modest associations for history of poor maternal or perinatal outcomes and borderline anaemia at the time of booking. No association with grand multiparity was found. CONCLUSIONS: These findings confirm the importance of previously recognised factors such as low parity, poor obstetric history, anaemia, and prolonged labour, but call into question the significance of grand multiparity. Previously undocumented factors such as maternal age greater than 35 years and occiput posterior head position emerged as predictors worthy of further investigation. 相似文献
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106.
Gerber R. Seongsoo Hong 《IEEE transactions on pattern analysis and machine intelligence》1995,21(5):389-404
We present a programming language called TCEL (Time-Constrained Event Language), whose semantics are based on time-constrained relationships between observable events. Such a semantics infers only those timing constraints necessary to achieve real-time correctness, without overconstraining the system. Moreover, an optimizing compiler can exploit this looser semantics to help tune the code, so that its worst-case execution time is consistent with its real-time requirements. In this paper we describe such a transformation system, which works in two phases. First, the TCEL source code is translated into an intermediate representation. Then an instruction-scheduling algorithm rearranges selected unobservable operations and synthesizes tasks guaranteed to respect the original event-based constraints 相似文献
107.
The present study is an exploratory survey attempting to get the point of view of the faculty of subjects considered responsible by teaching physical examination in the nursing undergraduate schools of S?o Paulo city that were selected for this study. The goals were: to detect the situation of teaching of propaedeutics basis; to identify factors that make them difficult; and to identify the recommendations of the faculty for the improvement of teaching and its implementation. The population studied was formed by 39 faculty of the subjects considered responsible by teaching physical examination. Results show us there is not a specific subject to teach physical examination, although it is taught mainly in Fundamental Nursing; faculty are not entirely prepared to teach physical examination. To improve teaching of physical examination, the faculty suggest enhancing their knowledge and skills as well as to create a specific subject to teach physical examination with sufficient hours according to the content. 相似文献
108.
DE Bierer LG Dubenko P Zhang Q Lu PA Imbach AW Garofalo PW Phuan DM Fort J Litvak RE Gerber B Sloan J Luo R Cooper GM Reaven 《Canadian Metallurgical Quarterly》1998,41(15):2754-2764
Cryptolepine (1) is a rare example of a natural product whose synthesis was reported prior to its isolation from nature. In the previous paper we reported the discovery of cryptolepine's antihyperglycemic properties. As part of a medicinal chemistry program designed to optimize natural product lead structures originating from our ethnobotanical and ethnomedical field research, a series of substituted and heterosubstituted cryptolepine analogues was synthesized. Antihyperglycemic activity was measured in vitro and in an NIDDM mouse model to generate the first structure-bioactivity study about the cryptolepine nucleus. 相似文献
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110.
Two polyacetylenic antibiotics, peniophorin A and B, have been isolated from a strain of Peniophora affinis. Both have antibacterial and antifungal activity, but B is 3 to 20 times more active than A. Gram-positive cocci and a strain of Proteus vulgaris were especially susceptible to these two antibiotics. Both peniophorins contained an aromatic ring; B was an acid, and A was neutral. Peniophorin B was shown to be 2-(1-oxo-2,4-pentadiynl)phenyl acetic acid. The structure of A was only partially elucidated; it is suspected to be 6-[2-(1-oxo-2,4-pentadiynl)phenyl]5-methoxy-3-oxo-4-hexene-1-ol. 相似文献