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11.
Kenneth O. Stanley 《Genetic Programming and Evolvable Machines》2007,8(2):131-162
Natural DNA can encode complexity on an enormous scale. Researchers are attempting to achieve the same representational efficiency
in computers by implementing developmental encodings, i.e. encodings that map the genotype to the phenotype through a process of growth from a small starting point to a mature
form. A major challenge in in this effort is to find the right level of abstraction of biological development to capture its
essential properties without introducing unnecessary inefficiencies. In this paper, a novel abstraction of natural development,
called Compositional Pattern Producing Networks (CPPNs), is proposed. Unlike currently accepted abstractions such as iterative
rewrite systems and cellular growth simulations, CPPNs map to the phenotype without local interaction, that is, each individual
component of the phenotype is determined independently of every other component. Results produced with CPPNs through interactive
evolution of two-dimensional images show that such an encoding can nevertheless produce structural motifs often attributed
to more conventional developmental abstractions, suggesting that local interaction may not be essential to the desirable properties
of natural encoding in the way that is usually assumed.
相似文献
Kenneth O. StanleyEmail: |
12.
R. G. Hohlfeld N. F. Comins D. Shalit P. A. Shorey R. C. Giles 《The Journal of supercomputing》1993,7(4):417-436
The development of massively parallel supercomputers provides a unique opportunity to advance the state of the art inN-body simulations. TheseN-body codes are of great importance for simulations in stellar dynamics and plasma physics. For systems with long-range forces, such as gravity or electromagnetic forces, it is important to increase the number of particles toN 107 particles. Significantly improved modeling ofN body systems can be expected by increasingN, arising from a more realistic representation of physical transport processes involving particle diffusion and energy and momentum transport. In addition, it will be possible to guarantee that physically significant portions of complex physical systems, such as Lindblad resonances of galaxies or current sheets in magnetospheres, will have an adequate population of particles for a realistic simulation. Particle-mesh (PM) and particle-particle particle-mesh (P3M) algorithms present the best prospects for the simulation of large-scaleN-body systems. As an example we present a two-dimensional PM simulation of a disk galaxy that we have developed on the Connection Machine-2, a massively parallel boolean hypercube supercomputer. The code is scalable to any CM-2 configuration available and, on the largest configuration, simulations withN = 128 M = 227 particles are possible in reasonable run times. 相似文献
13.
Robert Cummins 《Minds and Machines》1991,1(1):31-42
In response to Michael Morris, I attempt to refute the crucial second premise of the argument, which states that the formality condition cannot be satisfied non-stipulatively in computational systems. I defend the view of representation urged in Meaning and Mental Representation against the charge that it makes content stipulative and therefore irrelevant to the explanation of cognition. Some other reservations are expressed. 相似文献
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16.
含化学反应体系多相平衡计算方法的研究进展 总被引:1,自引:0,他引:1
首先给出了含化学反应体系多相平衡计算问题的数学方程,然后对国内外含化学反应体系多相平衡计算方法的现状和进展做了综述,包括经典的非化学计量系数法和化学计量系数法以及最近提出的稳定性分析法、全局最优法和遗传算法等,并具体介绍了化学计量系数法中两种常用算法-S-C算法和KZ算法以及遗传算法的算法原理和计算步骤。 相似文献
17.
Incorporating Ancestors' Influence in Genetic Algorithms 总被引:1,自引:1,他引:1
A new criterion of fitness evaluation for Genetic Algorithms is introduced where the fitness value of an individual is determined by considering its own fitness as well as those of its ancestors. Some guidelines for selecting the weighting coefficients for quantifying the importance to be given to the fitness of the individual and its ancestors are provided. This is done both heuristically and automatically under fixed and adaptive frameworks. The Schema Theorem corresponding to the proposed concept is derived. The effectiveness of this new methodology is demonstrated extensively on the problems of optimizing complex functions including a noisy one and selecting optimal neural network parameters. 相似文献
18.
电厂启动备用变压器继电保护应用分析 总被引:1,自引:0,他引:1
针对电厂备用变压器分支较多这一特殊情况,从理论上对保护配置与整定上存在的问题进行了深入分析,提出了切实可行的保护配置和整定计算方法,具有较高的应用价值和推广意义。 相似文献
19.
本文从麦克斯韦方程出发,在圆柱坐标系下建立了圆筒型直线电机的多层理论分析模用该模型对一台样机进行实例计算,并与磁阻抗法和实验值进行了比较,计算结果表明该方法的正确性和有效性。 相似文献
20.
M. Khater 《Computers & Industrial Engineering》1998,35(3-4):447-450
One of the transformer major design elements is its core design. The good performance of the transformer requires its coil core to be laminated and composed of different - widths stepped layers of specific steel packed together. For optimum design, the cross sectional shape of the core must be as circular as possible. So, an optimal packing can be attained by maximizing the steel core coverage. The number of different widths of steel plates n is selected to compose the packed core for a coil of diameter d. Then, an optimum sequence of decisions, for the n widths as well as the number of thin plates of each, is required. Dynamic programming (dp) is concerned with this optimum sequential decisions. An adequate forward recursive equation is formulated , because there isn't a standard dp model for all sequential decision making problems. To implement the recursive computations, a FORTRAN program is developed. Assuming that d is given the values 150, 200, 250, 300, 400 and 500 mm. while giving n the values from 2 to 15, the program is run at different combinations of n and d. It is found that maximum core coverage is sensitive to changing of n but it is slightly affected by changing of d. 相似文献