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71.
In order to perform business modelling as apart of information systems development, there is a need for frameworks and methods. The paper proposes a framework for business interaction based on a language/action perspective. The framework is an architecture of five generic layers. The first layer concept is ‘business act’, which functions as the basic unit of analysis. The following four layer concepts are ‘action pair’, ‘exchange’, ‘business transaction’, and ‘transaction group’. The framework is inspired by a similar framework constructed by Weigand et al. The paper makes a critical examination of this framework as a basis for the proposed framework. 相似文献
72.
The problem of weight initialization in multilayer perceptron networks is considered. A new computationally simple weight initialization method based on the usage of reference patterns is presented. A reference pattern is a vector which is used to represent data points that fall in its vicinity in the data space. On one hand, the proposed method aims to set the initial weight values to be such that inputs to network nodes are within the active region (in other words, nodes are not saturated). On the other hand, the goal is to distribute the discriminant functions formed by the hidden units evenly into the input space area where training data is located. The proposed method is tested with the widely used two-spirals classification benchmark problem and channel equalization problem where several alternatives for obtaining suitable reference patterns are investigated. Also, the effect of the initialization is studied when two commonly used cost functions are used in the training phase. These are the mean square error and relative entropy cost functions. A comparison with the conventional random initialization shows that significant improvement in convergence can be achieved with the proposed method. In addition, the computational cost of the initialization was found to be negligible compared with the cost of training. 相似文献
73.
In traditional approaches for clustering market basket type data, relations among transactions are modeled according to the items occurring in these transactions. However, an individual item might induce different relations in different contexts. Since such contexts might be captured by interesting patterns in the overall data, we represent each transaction as a set of patterns through modifying the conventional pattern semantics. By clustering the patterns in the dataset, we infer a clustering of the transactions represented this way. For this, we propose a novel hypergraph model to represent the relations among the patterns. Instead of a local measure that depends only on common items among patterns, we propose a global measure that is based on the cooccurences of these patterns in the overall data. The success of existing hypergraph partitioning based algorithms in other domains depends on sparsity of the hypergraph and explicit objective metrics. For this, we propose a two-phase clustering approach for the above hypergraph, which is expected to be dense. In the first phase, the vertices of the hypergraph are merged in a multilevel algorithm to obtain large number of high quality clusters. Here, we propose new quality metrics for merging decisions in hypergraph clustering specifically for this domain. In order to enable the use of existing metrics in the second phase, we introduce a vertex-to-cluster affinity concept to devise a method for constructing a sparse hypergraph based on the obtained clustering. The experiments we have performed show the effectiveness of the proposed framework. 相似文献
74.
Mayer Christopher B. Candan K. Selçuk Sangam Venkatesh 《Multimedia Tools and Applications》2004,24(3):233-251
Because of their size, service times, and drain on server resources, multimedia objects require specialized replication systems in order to meet demand and ensure content availability. We present a novel method for creating replication systems where the replicated objects' sizes and/or per-object service times are large. Such replication systems are well-suited to delivering multimedia objects on the Internet. Assuming that user request patterns to the system are known, we show how to create replication systems that distribute read load to servers in proportion to their contribution to system capacity and experimentally show the positive load distribution properties of such systems. However, when user request patterns differ from what the system was designed for, system performance will be affected. Therefore, we also report on results that reveal (i) how server loads are affected and (ii) the impact two system design parameters (indicators of a system's load distribution qualities) have on server load when request patterns differ from that for which a system was designed. 相似文献
75.
Joaquim Salvi Author Vitae Jordi Pagès Author Vitae Author Vitae 《Pattern recognition》2004,37(4):827-849
Coded structured light is considered one of the most reliable techniques for recovering the surface of objects. This technique is based on projecting a light pattern and viewing the illuminated scene from one or more points of view. Since the pattern is coded, correspondences between image points and points of the projected pattern can be easily found. The decoded points can be triangulated and 3D information is obtained. We present an overview of the existing techniques, as well as a new and definitive classification of patterns for structured light sensors. We have implemented a set of representative techniques in this field and present some comparative results. The advantages and constraints of the different patterns are also discussed. 相似文献
76.
A. G. Jackson 《Microscopy research and technique》1987,5(4):373-377
In general, diffraction patterns from the higher-order Laue zones are shifted with respect to the zero-order pattern. Expressions for the shift ( t ) have been derived in terms of the indices [u, v, w] of a zone, the interplanar spacing ( H ), and a reciprocal lattice vector [ g L (hkl)] in a holz. The resulting vector possesses the direction of t in terms of a zolz reciprocal lattice vector and has a magnitude which is a fraction of that of the zolz vector. Hence, the calculation of t allows quantitative determination of the location of specific planes in a holz with respect to the zolz, thus simplifying the determination of plane indices consistent with those used in the zolz. The expressions for determining t for cubic, hexagonal close-packed (hep), tetragonal, orthorhombic, and monoclinic crystal types are presented in a table and, when applied, allow calculation of t expressed as a fraction of a zolz vector. An example for graphite is presented to illustrate the use of the equation, and t vectors for several zones for the simple cubic system are tabulated. 相似文献
77.
利用安徽省宿州市1999—2010年的统计数据,运用塞尔奎因-钱纳里标准法分析其城市化与工业化发展阶段,采用协整检验、Granger因果检验对其城市化与工业化的因果关系进行实证研究。结果表明:1)宿州工业化和城市化水平低于全国平均水平,均处于初期发展阶段;2)宿州城市化与工业化有高度相关关系,城市化滞后于工业化;3)宿州当前城市化发展是工业化发展的Granger原因,加快城市化发展有利于促进工业化水平提高;4)宿州城市化水平与第二产业增加值比重和第三产业增加值比重具有长期稳定的协整关系,但与非农就业人口比重不存在长期稳定的均衡关系;5)宿州城市化水平与第二产业增加值比重和第三产业增加值比重的弹性系数分别为0.21和0.86,说明其城市化水平对第三产业的拉动作用要比对第二产业的拉动作用更大一些。因此宿州市应促进人口向中心城区的集聚,发挥城市化对工业化的促进作用。 相似文献
78.
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80.
Continuously Tunable Wettability by Using Surface Patterned Shape Memory Polymers with Giant Deformability 下载免费PDF全文
Lingyu Zhao Jun Zhao Yayun Liu Yufeng Guo Liangpei Zhang Zhuo Chen Hui Zhang Zhong Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(24):3327-3333
Designing smart surfaces with tunable wettability has drawn much attention in recent years for academic research and practical applications. Most of the previous methods to achieve such surfaces demand some particular materials that inherently have special features or complicated structures which are usually not easy to obtain. A novel strategy to achieve such smart surfaces is proposed by using the surface patterned shape memory polymers of chemically crosslinked polycyclooctene which shows a giant deformability of up to ≈730% strain. The smart surfaces possess the ability to continuously tune the wettability by controlling the recovery temperature and/or time. Coating the modified titanium dioxide nanoparticles onto such surfaces renders the surface superhydrophobicity and expands the tunable range of contact angles (CAs). Theoretical calculations of the CAs at different strains via modified Cassie model well explain the tunable wettability behaviors of such smart surfaces. 相似文献