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71.
水电厂的经济考核是发电公司经营管理的重点和难点,过去由于体制和考核手段的原因该问题一直没有解决好。现本文从水电厂正常生产和经济运行的要求出发,论述了经济考核的原则,讨论了水电厂生产和经济运行的措施及效益计算办法,提出了水电厂生产运行管理和考核的实用模式,期望对水电厂的生产运行管理和公平考核起到促进作用。  相似文献   
72.
In this paper, a bi-objective multi-products economic production quantity (EPQ) model is developed, in which the number of orders is limited and imperfect items that are re-workable are produced. The objectives of the problem are minimization of the total inventory costs as well as minimizing the required warehouse space. The model is shown to be of a bi-objective nonlinear programming type, and in order to solve it two meta-heuristic algorithms namely, the non-dominated sorting genetic algorithm (NSGA-II) and multi-objective particle swarm optimization (MOPSO) algorithm, are proposed. To verify the solution obtained and to evaluate the performance of proposed algorithms, two-sample t-tests are employed to compare the means of the first objective value, the means of the second objective values, and the mean required CPU time of solving the problem using two algorithms. The results show while both algorithms are efficient to solve the model and the solution qualities of the two algorithms do not differ significantly, the computational CPU time of MOPSO is considerably lower than that of NSGA-II.  相似文献   
73.
基于相似孤立系数的孤立点检测算法   总被引:1,自引:0,他引:1  
基于聚类的孤立点检测算法得到的结果比较粗糙,不够准确。针对该问题,提出一种基于相似孤立系数的孤立点检测算法。定义相似距离以及相似孤立点系数,给出基于相似距离的剪枝策略,根据该策略缩小可疑孤立点候选集,并降低孤立点检测算法的计算复杂度。通过选用公共数据集Iris、Labor和Segment—test进行实验验证,结果表明,该算法在发现孤立点、缩小候选集等方面相比经典孤立点检测算法更有效。  相似文献   
74.
Some decentralized smoothing problems are solved by applying a forward-pass fixed-interval smoother formula in discrete-time systems. It is assumed that a simple estimation structure consists of a global processor and of two local processors. Two cases are considered for the problems of decentralized smoothing and smoothing update: when the local backward-pass information filtered estimates are available, and when the local-smoothed estimates are available. Some features of present algorithms are discussed from the point of view of data transmissions and numerical computations, etc.  相似文献   
75.
Gene clusters are becoming promising tools for gene identification. The study reveals the purposive genomic distribution of genes toward higher inheritance rates of intact metabolic pathways/phenotypes and, thereby, higher fitness. The co-localization of co-expressed, co-interacting, and functionally related genes was found as genome-wide trends in humans, mouse, golden eagle, rice fish, Drosophila, peanut, and Arabidopsis. As anticipated, the analyses verified the co-segregation of co-localized events. A negative correlation was notable between the likelihood of co-localization events and the inter-loci distances. The evolution of genomic blocks was also found convergent and uniform along the chromosomal arms. Calling a genomic block responsible for adjacent metabolic reactions is therefore recommended for identification of candidate genes and interpretation of cellular functions. As a case story, a function in the metabolism of energy and secondary metabolites was proposed for Slc25A44, based on its genomic local information. Slc25A44 was further characterized as an essential housekeeping gene which has been under evolutionary purifying pressure and belongs to the phylogenetic ETC-clade of SLC25s. Pathway enrichment mapped the Slc25A44s to the energy metabolism. The expression of peanut and human Slc25A44s in oocytes and Saccharomyces cerevisiae strains confirmed the transport of common precursors for secondary metabolites and ubiquinone. These results suggest that SLC25A44 is a mitochondrion-ER-nucleus zone transporter with biotechnological applications. Finally, a conserved three-amino acid signature on the cytosolic face of transport cavity was found important for rational engineering of SLC25s.  相似文献   
76.
[Correction Notice: An erratum for this article was reported in Vol 13(2) of Psychological Methods (see record 2008-06808-007). In Figures 3B and 3D, the question marks (?) should read as multiplication signs (×). That is, it should read as β×λ?, β×λ?, and β×λ?? instead of β?λ?, β?λ?, and β?λ?? in Figure 3B and as γ×λ? and γ×λ? instead of γ?λ? and γ?λ? in Figure 3D.] In a recent article, A. Maydeu-Olivares and D. L. Coffman (2006; see record 2006-22258-002) presented a random intercept factor approach for modeling idiosyncratic response styles in questionnaire data and compared this approach with competing confirmatory factor analysis models. Among the competing models was the CT-C(M-1) model (M. Eid, 2000). In an application to the Life Orientation Test (M. F. Scheier & C. S. Carver, 1985), Maydeu-Olivares and Coffman found that results obtained from the CT-C(M-1) model were difficult to interpret. In particular, Maydeu-Olivares and Coffman challenged the asymmetry of the CT-C(M-1) model. In the present article, the authors show that the difficulties faced by Maydeu-Olivares and Coffman rest upon an improper interpretation of the meaning of the latent factors. The authors' aim is to clarify the meaning of the latent variables in the CT-C(M-1) model. The authors explain how to properly interpret the results from this model and introduce an alternative restricted model that is conceptually similar to the CT-C(M-1) model and nested within it. The fit of this model is invariant across different reference methods. Finally, the authors provide guidelines as to which model should be used in which research context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
Saltiness and fattiness were systematically varied in combinations of wheat bread (unsalted vs regular-salt), spread (none vs regular-salt and regular-fat), cheese (low-salt and low-fat vs low-fat). All possible combinations, amounting to sixteen samples of sandwich and milk, were presented to 43 subjects for ratings of pleasantness. The subjects also rated the pleasantness of individual components. The unsalted bread without spread but with low-salt, low-fat cheese and any of the milk types received the lowest hedonic ratings, whereas the regular-salt bread with spread and with any of the cheese and milk options received the highest. The pleasantness of individual components predicted the pleasantness of a combination by only 10–40% (multiple regression analysis). Thus the pleasantness of an entity depended on the pleasantness of components only to a very limited extent. The absence of major elements, such as spread on bread or the salty taste in bread, had major effects on acceptance.  相似文献   
78.
The proposition that the difference in memory span between Welsh digits and English digits is accounted for by the longer articulatory duration of Welsh digits is critically reexamined. Two methods of measuring digit duration are contrasted. One is derived from digits spoken in isolation, the other is based on digits spoken in list format. Duration of Welsh digits was greater only when spoken in lists; with isolated production Welsh digits were significantly shorter than English digits. Also, span was shorter for Welsh digits. The results are interpreted in the light of the different articulatory demands made at the junctures between words in the English and Welsh lists. A supplementary experiment, using English words, illustrated that articulatory complexity at item boundaries increased serial recall error. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
In a bid to enhance the search performance, this paper presents an improved version of reduced candidate mechanism (RCM), an algebraic codebook search conducted on an algebraic code‐excited linear‐prediction (ACELP) speech coder. This improvement is made on the basis of two findings in our prior work. The first finding is that a pulse with a high contribution in the associated track is more likely to serve as the optimal pulse in the optimal codevector; the second is that the speech quality can be well maintained at a search accuracy above 50% approximately. Subsequently, a new finding in this study is that there is a 0.8321 probability that the No. 1 ranked pulse in a global sorting by pulse contribution is indeed one of the optimal pulses. Hence, the No. 1 pulse in the global sorting is labeled as one of the optimal pulses, following which a sequence of search tasks is fulfilled through RCM. This proposed complexity reduction algorithm, implemented on a G.729A speech codec, takes as few as eight searches, a search load amounting to 2.5% of G.729A, 12.5% of global pulse replacement method (iteration = 2), 16.7% of iteration‐free pulse replacement method, and 50% of RCM (N = 2). This proposal is thus found to successfully reduce the required computational complexity to a great extent as intended. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
80.
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