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91.
Trigeneration or combined heat, cooling and power (CHCP) is becoming an increasingly important energy option, particularly on a small-scale basis (below 1 MWe), with several alternatives nowadays available for the cooling power production and the coupling to cogeneration systems. This paper deals with the introduction of a suitable framework for assessing the energy saving performance of trigeneration alternatives, orientated towards energy planning studies and the development of regulatory policies. In particular, a new generalized performance indicator—the trigeneration primary energy saving (TPES)—is introduced and discussed, with the aim of effectively evaluating the primary energy savings from different CHCP alternatives. The potential of the TPES indicator is illustrated through specific analyses run over different combinations of trigeneration equipment, providing numerical examples based on time-domain simulations to illustrate the dependence of the energy saving characteristics on the CHCP system configurations and equipment, as well as on the loading levels. In addition, the key aspect of adequately establishing the reference efficiencies for the conventional separate production of electrical, thermal and cooling power is addressed in detail. This aspect affects both equipment selection and potential profitability of the considered solutions under the outlook of receiving financial incentives.  相似文献   
92.
As microscopes have a very shallow depth of field, Z-stacks (i.e. sets of images shot at different focal planes) are often acquired to fully capture a thick sample. Such stacks are viewed by users by navigating them through the mouse wheel. We propose a new technique of visualizing 3D point, line or area markers in such focus stacks, by displaying them with a depth-dependent defocus, simulating the microscope's optics; this leverages on the microscopists' ability to continuously twiddle focus, while implicitly performing a shape-from-focus reconstruction of the 3D structure of the sample. User studies confirm that the approach is effective, and can complement more traditional techniques such as color-based cues. We provide two implementations, one of which computes defocus in real time on the GPU, and examples of their application.  相似文献   
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94.
Although the definition of service-oriented architecture (SOA) included the presence of a service registry from the beginning, the first implementations (e.g., UDDI) did not really succeed mainly because of security and governance issues. This article tackles the problem by introducing DREAM (Distributed Registry by ExAMple): a publish/subscribe-based solution to integrate existing, different registries, along with a match-making approach to ease the publication and retrieval of services. DREAM fosters the interoperability among registry technologies and supports UDDI, ebXML Registry, and other registries. The publish/subscribe paradigm allows service providers to decide the services they want to publish, and requestors to be informed of the services that satisfy their interests. As for the match-making, DREAM supports different ways to evaluate the matching between published and required services. Besides presenting the architecture of DREAM and the different match-making opportunities, the article also describes the experiments conducted to evaluate proposed solutions.  相似文献   
95.
Conifer trees resist pest and pathogen attacks by complex defense responses involving different classes of defense compounds. However, it is unknown whether prior infection by biotrophic pathogens can lead to subsequent resistance to necrotrophic pathogens in conifers. We used the infection of jack pine, Pinus banksiana, by a common biotrophic pathogen dwarf mistletoe, Arceuthobium americanum, to investigate induced resistance to a necrotrophic fungus, Grosmannia clavigera, associated with the mountain pine beetle, Dendroctonus ponderosae. Dwarf mistletoe infection had a non-linear, systemic effect on monoterpene production, with increasing concentrations at moderate infection levels and decreasing concentrations at high infection levels. Inoculation with G. clavigera resulted in 33 times higher monoterpene concentrations and half the level of phenolics in the necrotic lesions compared to uninoculated control trees. Monoterpene production following dwarf mistletoe infection seemed to result in systemic induced resistance, as trees with moderate disease severity were most resistant to G. clavigera, as evident from shorter lesion lengths. Furthermore, trees with moderate disease severity had the highest systemic but lowest local induction of α-pinene after G. clavigera inoculation, suggesting a possible tradeoff between systemically- and locally-induced defenses. The opposing effects to inoculation by G. clavigera on monoterpene and phenolic levels may indicate the potential for biosynthetic tradeoffs by the tree between these two major defense classes. Our results demonstrate that interactions between a biotrophic parasitic plant and a necrotrophic fungus may impact mountain pine beetle establishment in novel jack pine forests through systemic effects mediated by the coordination of jack pine defense chemicals.  相似文献   
96.
The measurement of object dimensions as well as the detection and localization of external defects are of large importance for many sectors in industry including agriculture, transportation and production. In this paper we investigate the feasibility of using commercial depth-sensing devices, based on a time-of-flight technology, such as the Kinect v2 camera, for the measurement and inspection of cuboidal objects (boxes). This paper presents a simplified system using only one Kinect sensor. At the beginning, object dimensions are roughly estimated by discovering the best-fit planes for a cloud of point based on a modified version of RANSAC (RANdom Sample Consensus). The precise geometry and morphology of the objects are then achieved by a transformation from depth to RGB representation of the points estimated as belonging to the object. RGB representation is finally processed (using scanlines on the RGB plane perpendicular to the initial edge estimate) to approximate at best the contour of the bounding box. In addition to the above, the paper proposes a method to automatically highlight defects on the objects’ surfaces: this inspection task is performed through the analysis of both the 2D object contours and the histogram of the normalized depth values. The proposed methodology takes a few seconds to deliver the results for the monitored object and, it experienced encouraging results in terms of accuracy. Indeed, the system measured the dimensions of a set of cuboidal objects with an average error of 5 mm and it was able to identify and locate defects and holes on lateral and topmost surfaces. The experimental outcomes pointed out that the system could be effectively exploited within industrial inspection applications, even more so if the low cost of the system is taken under consideration.  相似文献   
97.
Many websites allow users to rate items and share their ratings with others, for social or personalisation purposes. In recommender systems in particular, personalised suggestions are generated by predicting ratings for items that users are unaware of, based on the ratings users provided for other items. Explicit user ratings are collected by means of graphical widgets referred to as ‘rating scales’. Each system or website normally uses a specific rating scale, in many cases differing from scales used by other systems in their granularity, visual metaphor, numbering or availability of a neutral position. While many works in the field of survey design reported on the effects of rating scales on user ratings, these, however, are normally regarded as neutral tools when it comes to recommender systems. In this paper, we challenge this view and provide new empirical information about the impact of rating scales on user ratings, presenting the results of three new studies carried out in different domains. Based on these results, we demonstrate that a static mathematical mapping is not the best method to compare ratings coming from scales with different features, and suggest when it is possible to use linear functions instead.  相似文献   
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99.
In this paper, we have reviewed recent achievements in the field of asymmetric catalysis by metal complexes immobilized onto inorganic and organic supports. Besides allowing for facile catalyst recovery and reuse, immobilized metal complexes show a number of diverse applications and unique performances.  相似文献   
100.
Fatty acids, tocopherols, and phenolic compounds biogenesis from two major Spanish olive cultivars (Arbequina and Manzanilla) were analyzed for the function of the thermal regime during the fruit ontogeny in a non‐Mediterranean environment. Bilinear models characterized the dynamics of fatty acid biogenesis. Regressions between the accumulated thermal time (TT) and the levels of both oleic and linoleic acids showed different responses to temperature of each olive cultivar. After reaching similar absolute maximum oleic acid contents at similar TT, the levels of this fatty acid decreased markedly in cv. Arbequina and its final concentration was 10 % lower than that found in cv. Manzanilla. In both cultivars, concentrations of all tocopherol isoforms were negatively associated with the TT accumulated over the entire oil accumulation period. Dynamics of phenolic compounds biogenesis showed no clear tendencies with TT. Nevertheless, and whatever the stage of fruit development, secoiridoids were the major phenolic components. Results suggest greater sensitivity of fatty acid metabolism to temperature in cv. Arbequina. This fact points out the necessity of appropriate evaluation of the ambient thermal characteristics before introducing this cultivar into new growing environments.  相似文献   
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