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101.
Several longstanding issues in psychological research (e.g., self-determination vs. nonagentic determination in human action and nomothetic vs. idiographic research approaches) are explored. Reasons are presented that suggest why agentic and idiographic approaches (in combination with the more typical nomothetic, nonagentic studies) may enhance the predictive accuracy of psychological experiments. A study on the daily exercise behavior of 42 subjects over a 60-day period is presented and analyzed from 3 perspectives: nonagentic–nomothetic, nonagentic–idiographic, and agentic–nomothetic. The results suggest that substantial dividends in predictive accuracy accrue when nontraditional research perspectives are entertained. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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For many profoundly hearing-impaired listeners (hearing loss > 90 dB HL) speechreading is the most important means of communication; amplified speech may provide, at best, additional information to speechreading. In order to improve audiovisual communication, three speech pattern elements comprising voice-fundamental frequency (f0), the first formant (F1), and the first and the second formant (F1F2) were presented as supplements to speechreading. A fourth condition consisted of a natural speech supplement, a fifth of speechreading only. Twenty subjects were tested; all audiovisual speech scores were significantly higher than the purely visual scores. Audiovisual scores for amplified, natural speech were significantly higher than those for f0 and F1F2 coded speech. Scores for natural speech and for F1 coded speech were not significantly different. The relations between the increase in audiovisual speech scores over the visual scores and measures of difference limen for frequency (DLf) and gap detection were not clear. The most prominent correlations with the speech scores were found for the DLf at 125 Hz and for gap detection.  相似文献   
106.
Demographic futures are proposed as an empirical and normative guide for planning. Projections of demographic change help planners prepare future-oriented plans that are better targeted to the needs of a changing clientele. As an example, population changes in California highlight the growing importance of Latinos to the development of more compact cities. Demographic futures also entail normative interpretations of future scenarios as much as they do empirical relationships projected into the future. Several alternative stories are related of Latinos' future situation, each highlighting different value premises, problems, and conclusions. To effectively use demographic futures, planners must be conversant with both projected trends and competing interpretive stories.  相似文献   
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This article addresses the current identity crisis in the field of planning and offers a new vision of how it can be reconciled. Rather than retrench the profession and academia to a single paradigm of planning practice, we advocate expanding the domain of planning to reflect the rich variety of planning activities pursued by practitioners today. Key distinctions are proposed among three domains of planning—the organized profession, practice at large, and the academic field. Burgeoning activity within the realm of planning often occurs without the guidance of professional planners or academics. Working together, and following their distinctive missions, academia and the profession can better address emerging opportunities.  相似文献   
108.
Local housing-market effects on tenure choice   总被引:4,自引:0,他引:4  
The main objective of thepresent study is to find out which marketfactors affect homeownership attainment aftercontrolling for individual human capital. The1980 and 1990 individual Census data (PUMS) inthe U.S. are used to investigate the contextualinfluences on choosing two types of housing:single- and multi-family housing. Trichotomoustenure choice models are applied to fourrepresentative age groups. The study takesadvantage of the multi-level design, allowingrelationships between individual and housingmarket characteristics to vary from place toplace. One finding is that market variations aswell as individual characteristics affecttenure choices. The authors argue that researchon homeownership attainment should not onlyconsider individual or household attributes butshould be sensitive to spatiality thatrecognizes market effects. The conclusion isthat housing research needs to be comprehensiveenough to understand the complex interactionbetween the individual's human capital and themetropolitan housing-market characteristics.  相似文献   
109.
Concrete which contains waste products as aggregate is called ‘Green’ concrete. Use of hazardous waste in concrete-making will lead to green environment and sustainable concrete technology and so such concrete can also be called as ‘Green’ concrete. Concrete made with ceramic electrical insulator waste as coarse aggregate shows good workability, compressive, tensile and flexural strengths and modulus of elasticity. Further, study of its durability will ensure greater reliability in its usage. Permeation characters are used widely to quantify durability properties of concrete. This paper presents an experimental investigation on the permeation characteristics [volume of voids and water absorption (ASTM C642-06), chloride penetration (ASTM C1202-10), and sorption] of concrete with ceramic electrical insulator waste coarse aggregate (hereafter it is called recycled aggregate concrete) of six different water–cement ratios in comparison with those of corresponding conventional concrete mixes. From the results it has been observed that there is no significant change in the basic trend of permeation characteristics of this recycled aggregate concrete when compared to the conventional concrete. This recycled aggregate concrete possesses higher permeation characteristic values than those of conventional concrete. These values decrease with decrease in water–cement ratio for both the recycled aggregate concrete and the conventional concrete.  相似文献   
110.
Much economic activity depends on the environmentalresource base (soils, water, vegetation, climate) that ultimately underpins virtually all human endeavor. This environmental-resource support is obviously important for agriculture, forestry, fisheries and hydropower generation. It is less obviously important for public health: without regular supplies of domestic-household water with sufficient quantity and quality, the risk of sanitation-disease increases. Much the same applies, through indirect linkages, to such further economic sectors as communications and education.These considerations are especially significant for developing countries. A greater share of their economies is usually dependent on the environmental-resource base than is the case with developed-world economies; and at the same time, the resource base, being generally tropical in location, is more fragile and hence susceptible to depletion than is the case with temperate-zone countries. Thus there is a premium on safeguarding the environmental-resource base as an integral part of those processes known as sustainable development.This is a revised and expanded version of a paper prepared for a Seminar on Land and Water Management, Economic Development Institute, The World Bank, November 10–21, 1986. The author is a consultant in Environment and Development, Upper Meadow, Old Road, Headington, Oxford, United Kingdom. The views expressed in this paper are those of the author, and should not be attributed to the World Bank, to its affiliated organizations or to any individual acting on their behalf.  相似文献   
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