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121.
The goal of abstractive summarization of multi-documents is to automatically produce a condensed version of the document text and maintain the significant information. Most of the graph-based extractive methods represent sentence as bag of words and utilize content similarity measure, which might fail to detect semantically equivalent redundant sentences. On other hand, graph based abstractive method depends on domain expert to build a semantic graph from manually created ontology, which requires time and effort. This work presents a semantic graph approach with improved ranking algorithm for abstractive summarization of multi-documents. The semantic graph is built from the source documents in a manner that the graph nodes denote the predicate argument structures (PASs)—the semantic structure of sentence, which is automatically identified by using semantic role labeling; while graph edges represent similarity weight, which is computed from PASs semantic similarity. In order to reflect the impact of both document and document set on PASs, the edge of semantic graph is further augmented with PAS-to-document and PAS-to-document set relationships. The important graph nodes (PASs) are ranked using the improved graph ranking algorithm. The redundant PASs are reduced by using maximal marginal relevance for re-ranking the PASs and finally summary sentences are generated from the top ranked PASs using language generation. Experiment of this research is accomplished using DUC-2002, a standard dataset for document summarization. Experimental findings signify that the proposed approach shows superior performance than other summarization approaches.  相似文献   
122.
Software Quality Journal - Analyzing the behavior of sensors is becoming one of the key challenges due to their increasing use for decision making in IoT systems. The paper proposes an approach for...  相似文献   
123.
The current study presents results from a series of numerical analyses of non‐Newtonian liquid film formation on a rotating spoked annulus. The film flow of a common type of polyester, poly(ethylene terephthalate) (PET), on a vertically rotating disk was modeled numerically. Two different molecular weights, corresponding to different viscosities for PET, and under flow at different rotating speeds, were considered. The film thickness profile was obtained at different radial and angular positions of the rotating disk in the simulations, which is beneficial in calculating the volume of polymer taken up by the rotating disk and also in calculating the volumetric flow rates on the disk. Two types of disks, including a standard solid disk and a number of hollow disk designs with spoked annuli, were considered, and the film flow was modeled using a volume of fluid computational fluid dynamics analysis. The analyses of flow over spoked annulus designs highlighted the advantage of such designs over the use of a conventional solid disk. It was found that the variation in the film thickness for the spoked annulus was lower than that for the conventional solid disk. The parametric study also provided a favorable spoked annulus design for which the film thickness was essentially constant. A constant film thickness would provide a constant film flow, which can be a benefit to many industrial applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44943.  相似文献   
124.
This study focuses on the visual interface design of WebOPAC, which assists children in carrying out searching and browsing activities for bibliographical information in a library database. The existing interface of WebOPAC, called Ilmu, is investigated in this study; the interface is efficient in retrieving information from the database; however, its poor graphic design causes major usability problems. The graphic design of Ilmu is important in helping children to understand and visualise concepts of searching and browsing. Therefore, the interface must be constructed in such a way that can meet the needs of children aged 7–11 years. In this study, an analysis has been carried out on children’s requirements for the graphic design through participatory design activities using two approaches: cooperative inquiry and sketching of ideas. The cooperative Inquiry approach involved 40 children, while sketching children’s ideas involved 20 children as respondents. A total of 14 requirement specifications were generated and categorised into four areas—use of space, information organisation, function and use of colours; these would serve as a basis in designing a new WebOPAC interface. Synthesis of these requirements has shown that they are best supported through the implementation of visual interface display techniques. Chi-squared (χ 2) test was used to test the responses of children towards the usability of the new interface; the results showed a high level of acceptance by the children, recording a rate of 83.98 %.  相似文献   
125.
This paper describes the design and fabrication of an atom chip to be used in ultra-high-vacuum cells for cold-atom tunneling experiments. A fabrication process was developed to pattern micrometer- and nanometer-scale copper wires onto a single chip. The wires, with fabricated widths down to 200 nm, can sustain current densities of more than 7.5 × 107 A/cm2. Partially suspended wires, developed in order to reduce the Casimir–Polder force between atoms and surface, were also fabricated and tested. Extensive measurements for variable wire width show that the sustainable currents are sufficiently large to allow chip-based atom tunneling experiments. Such chips may allow the realization of an atom transistor.  相似文献   
126.
El-Oued Valley suffers from the problem of rising groundwater which affects agricultural and urban areas and degrades all aspects of the socioeconomic life of its inhabitants. This problem, which appeared in the 1980s, is primarily a result of overexploitation of deep groundwater, lack of sanitation network, and discharge of wastewater directly into the unconfined aquifer. To solve this problem, a megaproject was carried out, based on the principle of sewerage, to drain and evacuate excess water after treatment to a discharge site 70 km north of the region. In this project, the blade of groundwater above elevation of 60 m should be drained through wells of a vertical drainage system. However, the expected results have not been achieved in most affected cities, where the groundwater level continues to rise. Herein, we propose a solution to this problem, based on a new explanation of the hydrogeological structure of the unconfined aquifer that drives the rising groundwater to the surface. The main part of this research is based on interpretation of well tests carried out in wells of the vertical drainage system.  相似文献   
127.
Used tyres interact with soil, water and the atmosphere during temporary or permanent storage and also when used as additive or paving materials in landscapes, asphalt, concrete and for coastal protection. Various organic and inorganic compounds can penetrate into the environment from used tyres at various rates dependent on climatic and soil conditions. In this study, laboratory leaching batch experiments were conducted to determine the heavy metals and other constituents that could possibly penetrate into the leachate created during tyre usage/storage. The results obtained in this study showed that tyres were dissolved due to their usage and the climatic and environmental conditions thus leading to soil and groundwater pollution in their usage/reuse/storage/disposal areas. Zinc concentrations were the highest among the heavy metals measured in the simulated leachate. The average weight loss for all tyre samples was calculated as 3.6‰.  相似文献   
128.
129.
In this study, the influence of the cooling water temperature on the thermal efficiency of a conceptual pressurized‐water reactor nuclear‐power plant is studied through an energy analysis based on the first law of thermodynamics to gain some new insights into the plant performance. The change in the cooling water temperature can be experienced due to the seasonal changes in climatic conditions at plant site. It can also come into the question of design processes for the plant site selection. In the analysis, it is considered that the condenser vacuum varies with the temperature of cooling water extracted from environment into the condenser. The main findings of the paper is that the impact of 1°C increase in temperature of the coolant extracted from environment is predicted to yield a decrease of ~0.45 and ~0.12% in the power output and the thermal efficiency of the pressurized‐water reactor nuclear‐power plant considered, respectively. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
130.
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