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91.
Dhiah Al-Shammary Ibrahim Khalil Zahir Tari Albert Y. Zomaya 《Journal of Parallel and Distributed Computing》2013
The significant increase in the usage of Web services has resulted in bottlenecks and congestion on bandwidth-constrained network links. Aggregating SOAP messages can be an effective solution that could potentially reduce the large amount of generated traffic. Although pairwise SOAP aggregation, that is grouping only two similar messages, has demonstrated significant performance improvement, additional improvements can be done by including similarity mechanisms. Such mechanisms cluster several SOAP messages that have high degree of similarity. This paper proposes a fractal self-similarity model that provides a novel way of computing the similarity of SOAP messages. Fractal is proposed as an unsupervised clustering technique that dynamically groups SOAP messages. Various experimentations have shown good performance results for the proposed fractal self-similarity model in comparison with some well-known clustering models by only consuming 31% of the clustering time required by the K-Means and 23% when using principle component analysis (PCA) combined with K-Means. Furthermore, the proposed technique has shown “better” quality clustering, as the aggregated SOAP messages have much smaller size than their counterparts. 相似文献
92.
Herein we report for the first time the preparation and catalytic use of the ceria supported manganese(0) nanoparticles in hydrogen generation from the hydrolysis of sodium borohydride. They are in situ formed from the reduction of manganese(II) ions on the surface of ceria nanopowders during the catalytic hydrolysis of sodium borohydride in aqueous solution at room temperature. Manganese(0) nanoparticles are isolated from the reaction solution by centrifugation and characterized by a combination of analytical techniques. Nanoceria supported manganese(0) nanoparticles are highly active and long-lived catalysts providing a turnover frequency of 417 h?1 and 45,000 turnovers in hydrogen generation from the hydrolysis of sodium borohydride at 25.0 ± 0.1 °C. They also have high durability as they retain 55% of their initial catalytic activity after the fifth cycle of hydrolysis providing a release of 4 equivalent H2 gas per mol of sodium borohydride. The noticeable activity loss in successive runs of hydrolysis is attributed to the deactivation due to agglomeration. High activity and stability of ceria supported manganese(0) nanoparticles are ascribed to the unique nature of reducible cerium oxide. The formation of cerium(III) defects under catalytic conditions provides strong binding for the manganese(0) nanoparticles to oxide surface which makes the catalytic activity and stability favorable. Our report also includes the results of kinetic study of catalytic hydrolysis of sodium borohydride depending on the temperature, catalyst and substrate concentration. 相似文献
93.
Ochratoxin A (OTA) is a mycotoxin that can be found in several food commodities including cereals, wine, coffee, cacao, spices or dried fruits, resulting in chronic human exposure. The aim of our study was to investigate the presence of OTA in widely consumed cereal-derived products commercialized in Turkey. A total of 142 samples were collected from different supermarkets and traditional bazaars in Istanbul during 2008-2010 years. The analytical methods used in our study involved the liquid/liquid extraction of OTA, immunoaffinity clean-up and high performance liquid chromatography determination with fluorescence detection. The frequencies of OTA contamination were 21.62%, 19.05% and 55.95% and the mean concentrations of positive samples were 0.32 μg/kg, 0.14 μg/kg, 0.41 μg/kg for breakfast cereals, cereal-based baby foods and tarhana samples, respectively. Our findings show that contamination levels of OTA in all cereal-derived products were lower than the permitted level by European Commission Regulation. 相似文献
94.
Neural Processing Letters - This paper deals with the problem of the global asymptotic stability of Takagi–Sugeno (T–S) fuzzy Cohen–Grossberg neural networks with multiple time... 相似文献
95.
Gina Choi Andy H. Choi Louise A. Evans Sibel Akyol Besim Ben-Nissan 《Journal of the American Ceramic Society》2020,103(10):5442-5453
The prospect of modifying the surface properties of the substrate (or base) material to enhance its corrosion and wear resistance as well as its reliability, performance, and more importantly its bioactivity is made possible using nanocoatings. An effective technique of synthesizing high purity nanocoatings in addition to nanopowders and fibers is to utilize the sol-gel approach. It is an attractive and versatile method that can be carried out with relative ease. Ceramic coatings, such as hydroxyapatite (HAp), can be fabricated through chemical means from solutions and consequently complex shapes can be coated economically. Given the fact that mixing takes place on the atomic scale, one of the key advantages of the sol-gel technique is its capacity to produce homogeneous materials, and it has been shown that the mechanical properties of sol-gel coatings are enhanced due to the presence of nanocrystalline grain structures. This review covers a brief insight into the recent application of HAp nanocoatings derived from sol-gel technique. 相似文献
96.
Sibel Saracoglu Kadriye O. Saygi Ozgur D. Uluozlu Mustafa Tuzen Mustafa Soylak 《Food chemistry》2007,105(1):280-285
The levels of trace elements in different types of baby foods consumed in Turkey were determined by flame and graphite furnace atomic absorption spectrometry. Dry, wet and microwave digestion procedures were compared and the microwave digestion method was found to be the best. The accuracy of the method was ensured by using a standard reference material (NIST-SRM 8418 Wheat Gluten). The levels of elements in analyzed samples were found to be under legal limits. The range of the investigated elements were 0.52–4.38 μg/g, 0.22–7.20 μg/g, 1.02–67.5 μg/g, 0.92–37.2 μg/g, 0.12–0.32 μg/g, 2.02–68.8 μg/kg, 10.7–66.8 μg/kg, 0.05–10.3 μg/g, 2.67–25.4 μg/kg for Cu, Mn, Fe, Zn, Se, Cr, Al, Ni and Co, respectively. 相似文献
97.
In this study we calculate the P - T phase diagram of ice II - V - VI using a mean field model. Our calculated phase line equations are fitted to the experimental data from the literature. There is a very good agreement between our calculated and experimentally observed P - T phase diagram of ice II - V - VI. 相似文献
98.
Color comprises both subjective and objective aspects within its contextual nature. Research on color design tends to explore this seemingly contradictory concerns from theoretical point of view, as well as architectural and design practice. The aim of this study was to observe subjective, intuitive or heuristic and objective, knowledge‐based or analytical attitudes toward color in design education. In the study 84 introductory design students were surveyed progressively to understand their color decision criteria after completion of three 2‐dimensional colored exercises, specific in terms of color education. Students' responses to open‐ended questions were coded according to the 5 categories, under 2 decision making processes derived from the literature; heuristic approach: preferential and symbolic criteria, and analytic reasoning: formal, thematic, and systematic criteria. A distinction between associative and emotional aspects of symbolic criteria was also revealed by the data analysis. The findings showed a shift from heuristic responses to analytic reasoning, as expected. Additionally, it is also investigated that students not only used heuristic approaches but also analytical components (formal and systematic) of color decision making in varying degrees as well, even before any color subjects covered. Thematic color decisions became a major part of the students' design considerations upon completion of color subjects. The observed increase in the number of color criteria interrelated by the students' among almost all categories explicated a complex decision making process particularly in color design and education. These findings were expected to lead to some further understanding in color decision making in design. 相似文献
99.
Hospital waiting times are considerably long, with no signs of reducing any-time soon. A number of factors including population growth, the ageing population and a lack of new infrastructure are expected to further exacerbate waiting times in the near future. In this work, we show how healthcare services can be modelled as queueing nodes, together with healthcare service workflows, such that these workflows can be optimised during execution in order to reduce patient waiting times. Services such as X-ray, computer tomography, and magnetic resonance imaging often form queues, thus, by taking into account the waiting times of each service, the workflow can be re-orchestrated and optimised. Experimental results indicate average waiting time reductions are achievable by optimising workflows using dynamic re-orchestration. 相似文献
100.
In recent studies, contextual situations of applied colours are compared to colours presented as samples or chips. Findings of such studies point out different results in terms of similarities or differences between the evaluations of isolated/abstract colours and contextualized situations. Architectural and spatial contexts have their own characteristics regarding colouring criteria, so it is of great importance to examine the architectural/spatial colouring process from this point of view. This study explores this process by investigating the consistency of semantic ratings of four sequential stages of the architectural colour design process, namely, colour chips/samples, abstract compositions, perspective drawings and 3D models. The architectural context for the study was a simple interior space. Fifteen different colour schemes were applied on the four media representing the stages. Subjects rated the 15 sets against seven bipolar, five‐step semantic differential scales. The scales consisted of harmonious‐discord, pleasant‐unpleasant, comfortable‐uncomfortable, spacious‐confined, static‐dynamic, exciting‐calming and extroverted‐introverted. Findings indicated that there are significant associations between the evaluations of the abstract compositions, the perspective drawings and the 3D models; however, the evaluations of colour chips are significantly different than the others. The medium effect observed mostly between abstract and contextualized media. Additionally, factor analysis showed that pleasantness, harmony, spaciousness and comfort are connected in the evaluations of contextual situations, while pleasantness and harmony differ from spaciousness and comfort in the evaluations of colour chips and abstract compositions. The factor of activity (arousal) (dynamism, excitement, and extroversion) stays the same for all four media. It is also found that different colour characteristics are determinative over different media. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010 相似文献