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1.
Kyle A. Crawford
Osama K. Eyada PhD PE
《Computers & Industrial Engineering》1989,17(1-4):298-302The worldwide proliferation of fraudulent materials has brought about the need for a new approach to the control of purchased material quality. Nuclear power, defense, aerospace and many other industries are affected by the supply of poor quality clones that presume to be original replacement parts. Safety considerations abound as these highly defective materials are used in systems that are critical to the preservation of human lives. Commonly utilized quality assurance programs have not effectively stopped the influx of fraudulent materials. These programs fail to concentrate inspection efforts on materials and inspection attributes that would effectively prevent the acceptance of fraudulent materials. herein a solution is presented to this problem in the form of an expert system application. Information commonly available in industry is formulated into a knowledge based system wherein advisories are given to the user regarding key purchased material receipt inspection strategies. 相似文献
2.
Jin B. Ong Osama K. Eyada PhD PE Abu S. Masud PhD PE 《Computers & Industrial Engineering》1989,17(1-4):85-89
This paper presents a Knowledge-based system (KBS) developed to allow users, who may not be knowledgeable about sensors, to select sensors suitable for their specific needs. The KBS runs on a micro-computer. The selection criteria are user specified and are based on the desired measurement parameters. The system output includes all of the operational and dimensional parameters of the recommended sensor, price, and vendor information. 相似文献
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Covariance structures analysis is often used in nursing research to appraise statistical models reflecting complex human health processes. The model selection approach in covariance structures analysis is designed to select the "best" model from a specified set of theoretically defensible, competing alternatives, all of which are viewed as approximations. Model selection criteria explicitly incorporate both model misfit in the population and sampling error to evaluate the set of models. The result is that interpretability of model parameters and goodness-of-fit are enhanced simultaneously. Relative merits of the model selection approach are identified in light of technical concerns, parsimony, and use of scientific theory in nursing. 相似文献
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The difference in attention and cognitive performance between 26 hypotensive (systolic blood pressure < 100 mmHg and diastolic blood pressure < 60 mmHg) and 22 normotensive female university students was assessed. Attention was examined with contingent negative variation (CNV) recorded using light and tone as S1 and S2. Cognitive performance was assessed by free recall of a list of words and two German tests of cognitive speed performance and sustained attention: Zahlen-Verbindungs-Test and d2. The hypotensive participants demonstrated a lower increase in negativity on the CNV. Moreover, in the free recall test, hypotensive individuals remembered fewer words, in comparison with normotensive subjects. Scores for hypotensive individuals on the Zahlen-Verbindungs-Test and d2 were also lower. No difference was found in reaction times to imperative stimuli (S2). 相似文献
7.
Johan Gottfried Erichsen (1713-68), born in Germany and chief medical officer in Bergen from 1747, was probably the first to perform a forceps delivery in Norway, on 14 February 1748. The mother, who had been in labour for five days, survived; the child, however, did not. The obstetric forceps had been a secret in the Chamberlen family and had become more widely known only a few decades earlier. Erichsen, who was the first man-midwife in Norway, had learned obstetrics in Paris by the younger Grégoire. He mastered both the techniques of internal version and forceps delivery. This article describes Erichsen's medical and obstetric background and his qualifications for operative obstetrics. He worked in the period when the obstetric forceps changed obstetrics, birth delivery became an arena also for men, and a part of medicine. Obstetrics was established as a science and physicians had a tool whereby also children could be saved during complicated delivery. 相似文献
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P Mamunes PE Prince NH Thornton PA Hunt ES Hitchcock 《Canadian Metallurgical Quarterly》1976,57(5):675-680
An analysis was made of the obstetric history of 1,360 patients who were delivered in 1971. It involved 3,185 pregnancies. The aim of the study was to evaluate the risk of spontaneous termination of the pregnancy, worked out from its demographic aspect. Several ideas are worthy of consideration. The risk of spontaneous intra-uterine death is cumulative, sharply increased by a repetition of such cessation of pregnancy. The same patients often undergo intentional abortion repeatedly. The respective risks of spontaneous and provoked interruption of pregnancy have been studied in greater detail as a function of parity. 相似文献
10.
Thirty-six cases of premature thelarche in girls 9 months to 7 years old have been studied. In most cases, breast development began before 3 years and came to regression. Onset after 3 years was less common and led usually to breast persistance. Height was lightly but significantly advanced. Plasma levels of estrone, estradiol (in 21 cases) and gonadotropins (FSH and LH, in 12 cases) were not significantly increased. However, LH-RH test (in 12 cases) suggested prolongation and/or increase of the physiologic gonadotropic hyperactivity of normal female infants. 相似文献