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71.
Divyani Kohli Richard Sliuzas Norman Kerle Alfred Stein 《Computers, Environment and Urban Systems》2012
Information about rapidly changing slum areas may support the development of appropriate interventions by concerned authorities. Often, however, traditional data collection methods lack information on the spatial distribution of slum-dwellers. Remote sensing based methods could be used for a rapid inventory of the location and physical composition of slums. (Semi-)automatic detection of slums in image data is challenging, owing to the high variability in appearance and definitions across different contexts. This paper develops an ontological framework to conceptualize slums using input from 50 domain-experts covering 16 different countries. This generic slum ontology (GSO) comprises concepts identified at three levels that refer to the morphology of the built environment: the environs level, the settlement level and the object level. It serves as a comprehensive basis for image-based classification of slums, in particular, using object-oriented image analysis (OOA) techniques. This is demonstrated by with an example of local adaptation of GSO and OOA parameterization for a study area in Kisumu, Kenya. At the object level, building and road characteristics are major components of the ontology. At the settlement level, texture measures can be potentially used to represent the contrast between planned and unplanned settlements. At the environs level, factors which extend beyond the site itself are important indicators, e.g. hazards due to floods plains and marshy conditions. The GSO provides a comprehensive framework that includes all potentially relevant indicators that can be used for image-based slum identification. These characteristics may be different for other study areas, but show the applicability of the developed framework. 相似文献
72.
This paper is the second in a series recording the effects of breed and nutrition on the productive traits of Nelore, Guzerá, Charolais and Canchim cattle in south-east Brazil. Significant treatment variations were recorded in carcase bone weights but differences in meat to bone ratios were not sufficiently marked to demonstrate that bone might grow at the expense of muscle when animals are maintained on particularly severe nutritional regimes. A simple carcase weight to length ratio was shown to be highly correlated with total bone proportion but not with yield of saleable meat. Recovery of total saleable meat was only marginally and not significantly affected by breed but was significantly affected by treatment. The increased levels of fatness in the carcases of the zebu and, in particular, all animals finished in feedlot, that affected the yield of saleable meat, was also thought to be responsible for the decreased recovery of first quality meat in these carcases. In general, tissue differences were more noticeable between treatments than between breeds and reflected the varying nutritional status of the animals pre-slaughter. 相似文献
73.
Norman GA 《Meat science》1982,6(2):79-96
Significant differences in a number of economically important appearance and palatability traits were recorded between the Bos indicus and Bos taurus breeds. Muscles from the Charolais and Canchim animals were consistently and significantly lighter in colour than those from the zebu breeds, even after pH effects had been taken into account. Differences were shown to be directly related to variations in muscle myoglobin levels, but may have been complicated by observed textural differences. Muscles from the zebu animals were not noticeably coarser grained, having significantly larger fibre diameters and fibre bundle sizes. The inferiority of the Bos indicus breeds in terms of muscle tenderness was clearly demonstrated. Significantly higher shear force values were recorded in all muscles from the Nelore and Guzera breeds, except the Psoas major. These differences were also detected by taste panel evaluation. Major differences between breeds were demonstrated in the thermo-stability of extracted intra-muscular connective tissue elements, being highest in the zebu breeds, intermediate in the Canchim and lowest in the Charolais. These solubility characteristics were thought to be due to differences in the relative proportions of genetically different collagen types in the muscles and an association between coarseness of texture and toughness was shown. 相似文献
74.
75.
Aviles Fredy; Earleywine Mitchell; Pollock Vicki; Stratton Joy; Miller Norman 《Canadian Metallurgical Quarterly》2005,19(1):108
The authors examined alcohol's effect on triggered displaced aggression, the hostile reaction to a second provoking person after provocation from a first. Participants consumed an alcoholic or a nonalcoholic beverage. Subsequently, one individual provoked all of them with moderate intensity. Then, 2 groups were studied: those who received or who failed to receive a second provocation of minimal intensity. Consistent with prior research, participants who received a second, minimal provocation displayed more aggression than those who did not. After participants drank alcohol, the magnitude of this difference was significantly greater, indicating that alcohol increases triggered displaced aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
The mapping of the human genome has reawakened interest in the topic of race and genetics, especially the use of genetic technology to examine racial differences in complex outcomes such as health and intelligence. Advances in genomic research challenge psychology to address the myriad conceptual, methodological, and analytical issues associated with research on genetics and race. In addition, the field needs to understand the numerous social, ethical, legal, clinical, and policy implications of research in this arena. Addressing these issues should not only benefit psychology but could also serve to guide such thought in other fields, including molecular biology. The purpose of this special issue is to begin a discussion of this issue of race and genetics within the field of psychology. Several scholars who work in the fields of genetics, race, or related areas were invited to write (or had previously submitted) articles sharing their perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Increasingly, application developers are looking for ways to provide users with higher levels of personalization that capture different elements of a user’s operating context, such as her location, the task that she is currently engaged in, who her colleagues are, etc. While there are many sources of contextual information, they tend to vary from one user to another and also over time. Different users may rely on different location tracking functionality provided by different cell phone operators; they may use different calendar systems, etc. In this article, we describe work on a Semantic e-Wallet aimed at supporting automated identification and access of personal resources, each represented as a Semantic Web Service. A key objective is to provide a Semantic Web environment for open access to a user’s contextual resources, thereby reducing the costs associated with the development and maintenance of context-aware applications. A second objective is, through Semantic Web technologies, to empower users to selectively control who has access to their contextual information and under which conditions. This work has been carried out in the context of myCampus, a context-aware environment aimed at enhancing everyday campus life. Empirical results obtained on Carnegie Mellon’s campus are discussed. 相似文献
78.
This paper presents a formulation of the facilities block layout problem which explicitly considers uncertainty in material handling costs on a continuous scale by use of expected values and standard deviations of product forecasts. This formulation is solved using a genetic algorithm meta-heuristic with a flexible bay construct of the departments and total facility area. It is shown that depending on the attitude of the decision-maker towards uncertainty, the optimal design can change significantly. Furthermore, designs can be optimized directly for robustness over a range of uncertainty that is pre-specified by the user. This formulation offers a computationally tractable and intuitively appealing alternative to previous stochastic layout formulations that are based on discrete scenario probabilities. 相似文献
79.
Rats were exposed to shock-paired cues immediately after training on an appetitive preference task. Elevated levels of freezing in and active avoidance of the shock-paired compartment were observed, and memory for the appetitive task was improved when tested 24 hr later. Intra-amygdala muscimol injected before the posttraining exposure eliminated freezing, avoidance, and memory modulation. The blockade of both freezing and active avoidance, which involve competing behavioral tendencies, makes it unlikely that the amygdala itself generates either behavior. The elimination of conditioned memory modulation suggests that conditioned neurohormonal responses were blocked. These conditioned internal responses may comprise the intervening variable of "conditioned fear" and may promote observable behaviors, the form of which is determined by the environment in which they occur. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Lambert Sharon F.; McCreary Beth T.; Joiner Thomas E.; Schmidt Norman B.; Ialongo Nicolas S. 《Canadian Metallurgical Quarterly》2004,72(5):904
In this study, the authors examined the validity of the tripartite model of anxiety and depression (L. A. Clark & D. Watson, 1991) in a community epidemiological sample of 467 urban African American youth. Participants completed the Baltimore How I Feel (N. S. Ialongo, S. G. Kellam, & J. Poduska, 1999), a measure of anxiety and depressive symptoms, in Grades 6 and 9. Confirmatory factor analyses indicated that a 3-factor model representing the tripartite model fit the data well and better than competing models. Longitudinal confirmatory factor analysis revealed configural invariance of the tripartite factor structure. However, a predicted divergence among dimensions over time was not evidenced. High correlations among the tripartite dimensions suggest that anxiety and mood symptoms may not differentiate in urban youth. Results are discussed in terms of the ethnicity and urban context of this community sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献