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71.
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Joseph M. Watson 《Planning Perspectives》2017,32(4):639-649
In Looking Backward (1888) and Equality (1897), Edward Bellamy offered two distinct but interrelated visions of a utopian future. The first and more famous book was set in a luxuriant, centralized metropolis. The sequel detailed decentralized, suburbanized infrastructures. Within the literature on Bellamy these emendations have been treated as evidence of regressive anti-urbanism. This paper argues instead that Bellamy used correlations between topography and technology to mediate an evolving approach to social reform. The discrepancies between the two texts did not represent abandonment of the city but rather an expansion of the scale and scope necessary to ensure social progress. While Looking Backward has often been invoked in relation the Garden City and City Beautiful movements, a new reading of Equality offers opportunities to rethink Bellamy’s relationship to planning history. 相似文献
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J. D. Watson J. D. Allen C. A. Mattson S. M. Ferguson 《Structural and Multidisciplinary Optimization》2016,53(6):1277-1294
System evolvability is vital to the longevity of large-scale complex engineered systems. The need for evolvability in complex systems is a result of their long service lives, rapid advances to their integrated technologies, unforeseen operating conditions, and emerging system requirements. Building excess capability into complex systems can improve their ability to evolve while in service. However, excess capability increases initial build cost and operating cost, which is compounded across the service life of the system. Excess capability that is eventually used adds benefit by allowing for in-service evolution to meet emerging system requirements. Therefore, there is a trade-off between the cost of excess capability initially built into the system and the benefit that is added to the system by enabling future evolution. This paper introduces a process for optimizing the amount of excess capability in a complex system. This process results in a set of evolvable systems without excessive cost. We demonstrate how this process can be used to select the amount of excess capability that should be included in a military ground vehicle. 相似文献
75.
Child undernutrition, a form of malnutrition, is a major public health burden in developing countries. Supplementation interventions targeting the major micronutrient deficiencies have only reduced the burden of child undernutrition to a certain extent, indicating that there are other underlying determinants that need to be addressed. Aflatoxin exposure, which is also highly prevalent in developing countries, may be considered an aggravating factor for child undernutrition. Increasing evidence suggests that aflatoxin exposure can occur in any stage of life, including in utero through a trans-placental pathway and in early childhood (through contaminated weaning food and family food). Early life exposure to aflatoxin is associated with adverse effects on low birth weight, stunting, immune suppression, and the liver function damage. The mechanisms underlying impaired growth and aflatoxin exposure are still unclear but intestinal function damage, reduced immune function, and alteration in the insulin-like growth factor axis caused by the liver damage are the suggested hypotheses. Given the fact that both aflatoxin and child undernutrition are common in sub-Saharan Africa, effective interventions aimed at reducing undernutrition cannot be satisfactorily achieved until the interactive relationship between aflatoxin and child undernutrition is clearly understood, and an aflatoxin mitigation strategy takes effect in those vulnerable mothers and children. 相似文献
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Information systems (IS) research has drawn heavily on social and cognitive psychology to explain technology adoption. Indeed, the many variations of the technology acceptance model all share these same theoretical foundations. Focusing exclusively on the socio-cognitive lens can lead to overlooking enhanced explanations of technology acceptance, such that new theoretical perspectives may be warranted. In this qualitative grounded theory study, we discovered how the lens of evolutionary psychology, as embodied in the Four-Drive model, was helpful in understanding technology acceptance across three organizational sites. We contend that evolutionary psychology is an important addition to the theoretical repertoire of IS researchers, and propose including ‘evolved psychological mechanisms’ within traditional models of technology acceptance. 相似文献
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Jane M. Watson Ben A. Kelly 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(2):145-166
Abstract: A task adapted from one used by Tversky and Kahneman (1971) was used in an interview or questionnaire context with 122 students from Grade 3 to Grade 13. Two questions assessed student understanding of the relationship of a sample to a population and of the expected value of the arithmetic mean, with and without information on a single value from the sample. Combining responses to the two questions, increasingly complex hierarchical sequences were identified in the observed responses in relation to the expected value of the means, an expectation variable, and in relation to the degree that ideas about variation were used to support judgements, a variation variable. Using data from another task performed by 68 of the students, responses were associated with the observed development of understanding of sampling more generally, a basic sampling variable. Overall, the associations of levels of response among the variables was not strong, suggesting more explicit discussion of sampling issues is required in classrooms. 相似文献
80.
Ventilation system analysis for underground mines has remained mostly unchanged since the Atkinson method was made popular by Mc Elroy in 1935. Data available to ventilation technicians and engineers is typically limited to the quantity of air moving through any given heading. Because computer-aided modelling, simulation, and ventilation system design tools have improved, it is now important to ensure that developed models have the most accurate information possible. This paper presents a new technique for estimating underground drift friction factors that works by processing 3 D point cloud data obtained by using a mobile Li DAR. Presented are field results that compare the proposed approach with previously published algorithms, as well as with manually acquired measurements. 相似文献