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31.
The presence of outliers can considerably degrade the performance of linear recursive algorithms based on the assumptions that measurements have a Gaussian distribution. Namely, in measurements there are rare, inconsistent observations with the largest part of population of observations (outliers). Therefore, synthesis of robust algorithms is of primary interest. The Masreliez–Martin filter is used as a natural frame for realization of the state estimation algorithm of linear systems. Improvement of performances and practical values of the Masreliez‐Martin filter as well as the tendency to expand its application to nonlinear systems represent motives to design the modified extended Masreliez–Martin filter. The behaviour of the new approach to nonlinear filtering, in the case when measurements have non‐Gaussian distributions, is illustrated by intensive simulations. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
32.
Although Hodgkin's disease is considered one of the "curable" cancers, the high cure rates associated with this disease are not accomplished without risk of potentially severe, immediate, and late side effects. Because the predominant histologic subtype of Hodgkin's disease found in the United States generally affects the 15- to 25-year-old age group, the disease, its treatment, and the side effects of treatment will affect many women of childbearing age. The treatment and its effects on the patient and offspring, including posttreatment fertility, are key issues for perinatal nurses.  相似文献   
33.
Modern medicine uses large amounts of one-way-devices. This includes mass articles as well as technically sophisticated ones, all of them in accordance with GMP (Good-manufacturing-practice) guidelines. Recycling of selected one-way devices in technically possible and economically useful. Prerequisite for recycling is the inclusion of legal, economic and ecologic points of view. In addition the validation of processes and agreement on installation of continuous quality control is necessary to minimise risks. We suggest admission of recycling and reuse of one-way devices and suggest to proceed stepwise: 1. Principal decision to permit recycling 2. Appointment of an interdisciplinary Federal Board "Medical Devices" for coordination and channelling of activities 3. Selection of products for recycling 4. Principal decision for the systematics of the process together with: process control, product control during a pre-testing stage, random tests in prospective, multi-centre studies for the control of production and use. 5. Introduction of internal quality control systems to allow internal and external control of routine work.  相似文献   
34.
Novak G  Jarrett T 《Applied optics》1995,34(10):1672-1677
Using a technique for CCD polarimetry, we have obtained stellar polarization data with the 0.9-m telescope on Kitt Peak and with the Tek 2048 CCD camera. Measurements of stars viewed through holes in polarizing filters serve to correct for variations in atmospheric transparency. For the brightest stars the uncertainties in the measured polarization during a single, hour-long, polarimetric sequence are 0.3-0.5%, because of the residual effects of the variations in transparency. For fainter stars we are Poisson noise limited. Our technique provides some advantages over other techniques for CCD polarimetry, primarily because it can be easily integrated into existing photometric systems.  相似文献   
35.
OBJECTIVE: To document the incidence, source, and reasons for all complaints received by a large municipal emergency medical services (EMS) program. METHODS: A retrospective review of all complaints received during three consecutive years (1990-1992) in a centralized EMS system serving a large municipality (population 2 million). All cases were categorized by year, source, and nature of the complaint. RESULTS: In the three study years, EMS responded to 416,892 incidents with nearly a half-million patient contacts. Concurrently, 371 complaints were received (incidence of 1.12 per thousand); 132 in 1990, 129 in 1991, and 110 in 1992. Most complaints involved either: 1) allegations of "rude or unprofessional conduct" (34%), 2) "didn't take patient to the hospital" (19%), or 3) "problems with medical treatment" (13%). Only 1.6% (n = 6) were response-time complaints. Other complaints included "lost/damaged property," "taken to the wrong hospital," "inappropriate billing," and "poor driving habits." The most common sources were patient's families (39%) and the patients themselves (30%). Only 7.8% were from health care providers. CONCLUSION: Reviews of complaints provide information regarding EMS system performance and reveal targets for quality improvement. For the EMS system examined, this study suggests a future training focus on interpersonal skills and heightened sensitivities, not only toward patients, but also toward bystanders and family members.  相似文献   
36.
There is growing evidence that face recognition is "special" but less certainty concerning the way in which it is special. The authors review and compare previous proposals and their own more recent hypothesis, that faces are recognized "holistically" (i.e., using relatively less part decomposition than other types of objects). This hypothesis, which can account for a variety of data from experiments on face memory, was tested with 4 new experiments on face perception. A selective attention paradigm and a masking paradigm were used to compare the perception of faces with the perception of inverted faces, words, and houses. Evidence was found of relatively less part-based shape representation for faces. The literatures on machine vision and single unit recording in monkey temporal cortex are also reviewed for converging evidence on face representation. The neuropsychological literature is reviewed for-evidence on the question of whether face representation differs in degree or kind from the representation of other types of objects.  相似文献   
37.
TD Mays  KD Mazan 《Canadian Metallurgical Quarterly》1996,51(1-3):93-102; discussion 102-9
The National Cancer Institute (NCI) is the US Government's principal agency for research on the prevention, diagnosis and treatment of cancer. A critical component of the Institute's mission is the identification and development of new and promising treatments for cancer and AIDS. For many years these efforts have included a program to investigate natural products for potential new therapeutic agents. In 1986, with the advent of new screening techniques, the National Cancer Institute stepped up its exploration of natural products and began world-wide collections of plants in tropical and subtropical regions. In recognition of the principles of the Biodiversity Treaty, NCI appreciates that continued access to the natural products of these countries depends on the Institute's ability to recognize the contributions of these source countries and their indigenous peoples, and to provide them adequate incentives to conserve their natural resources for the purposes of drug discovery. Accomplishing this goal presented several legal issues for the National Cancer Institute. As an agency of the US government, the NCI has an adjunct statutory mission to facilitate the transfer of technology developed through the Institute's programs into the private sector for further development and commercialization, and NCI operates under a national policy to use the patent system to transfer Federally supported research to the private domestic sector. Reliance on patent law may limit the Institute's ability to recognize the rights of source countries and their indigenous people and provide compensation for their contributions. However, other legal instruments, such as contracts, can serve as interim measures to provide compensation to source countries and indigenous populations. The National Cancer Institute's Letter of Collection agreement (LOC, formerly the "Letter of Intent'), is an example of an alternative means that "fills-in the gaps' created by patent law and through which source countries may share in the benefits of natural product development.  相似文献   
38.
This study develops a decision method for evaluating the social acceptability of industrial controls on hazardous materials. Decisions are based on a "multiple criteria approach" that jointly considers measures such as risk-benefit tradeoff, minimum reducible health risk, maximum acceptable cost and implicit value of human life. Health risks are calculated by combining separate estimates of production and usage patterns, emissions to air and water, effectiveness of controls, pollutant dispersion and human susceptibility. Economic benefits consider employment, trade and consumer impacts, as well as direct costs of controls. The analysis focuses on asbestos as an example hazard. Relative values of hazard reduction alternatives are examined for asbestos manufacturing exhaust filters and for asbestos substitutes in brake linings. Preliminary calculations indicate risk reductions of these alternatives cannot justify their social costs.  相似文献   
39.
This study is concerned with the diagnostic process of psychiatrists. Two concepts are investigated; the internalized nosological theory and the psychiatric diagnostic scheme. If patients or diseases are judged on predefined lists of symptoms (e.g. AMDP-list), we assume that judgments are based on the first one. If the psychiatrist, however, is free in the choice of relevant attributes in judging patients or diseases, we assume that his judgments are based on his individual diagnostic scheme. Results show high agreement in internalized nosological theories, but strong individual differences in diagnostic schemes. Interindividual agreement in internalized nosological theories is still greater than intraindividual agreement between diagnostic scheme and nosological theory. This proves that distinguishing the two concepts is meaningful. Structural components of both concepts, e.g., their dimensions, pregnant structures, and their metric, were analyzed by multidimensional scaling. We assume that the psychiatric diagnostic scheme determines the clinical diagnosis in everyday practice, whereas the internalized nosological theory is of importance mainly in research. The differences between both concepts suggest that lists of symptoms are not very helpful in analyzing clinical diagnosis. Thus, in order to achieve greater agreement in diagnosis, further and detailed analysis of individual "implicit" theories which determine the greater part of diagnostic schemes is necessary.  相似文献   
40.
Previous research demonstrated that 12 mo of total social isolation initiated at birth produced severe and seemingly permanent social deficits in rhesus monkeys. Such monkeys exhibited self-clasping, self-mouthing, and other stereotypic, self-directed responses. Recent research has indicated that 6-mo-isolated monkeys could develop social behaviors if exposed to younger, socially unsophisticated "therapist" monkeys. In the present experiment, 4 12-mo isolate-reared monkeys developed appropriate species-typical behavior through the use of adaptation, self-pacing of visual input, and exposure to 4 younger "therapist" monkeys. Adaptation enabled the isolate Ss to become familiar with their postisolation environment, while self-pacing facilitated their watching the therapist Ss' social interactions. The isolates showed a marked decrease in self-directed behaviors following extensive intimate contact with the therapists. Species-typical behaviors significantly increased during this period, so that the isolate behavioral repertoire did not differ substantially from the therapist behavioral repertoire by the end of the therapy period. Results clearly fail to support a critical period for socialization in the rhesus monkey, and an alternative environment-specific learning hypothesis is proposed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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