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排序方式: 共有433条查询结果,搜索用时 15 毫秒
91.
新型履齿履带试验研究 总被引:1,自引:1,他引:0
本文反映新型履齿带的最新试验研究成果.在新型履齿带对履带式车辆的 能系数fφμ改善的基础上,进一步试验研究了对牵引系数q=φ-f车辆经济性Ge等性能改善 的效果.同时,开始对人f、φ、μ、q、Ge等的影响因素V、δz、δy作了探索性试验研究. 相似文献
92.
80Kr核谱中4个8+态的微观研究 总被引:2,自引:1,他引:1
应用微观sdIBM-2 2q.p.案,计算了^80Kr核的基态带、γ带和部分高自旋态能诸,计算值与最新实验结果符合得较好。方案指认81^ 、82^ 和83^ 态很可能分属基态带、两中子和两质子准粒子态,而84^ 态则属于γ带,并都获得最新实验结果支持。计算表明:核的一个玻色于突然拆对不会明显改变前后状态。讨论了两准粒子顺排态能量及其指认问题。 相似文献
93.
We present a compositional method for deciding whether a process satisfies an assertion. Assertions are formulas in a modal q10r40327544/xxlarge957.gif" alt="ngr" align="BASELINE" BORDER="0">-calculus, and processes are drawn from a very general process algebra inspired by CCS and CSP. Well-known operators from CCS, CSP, and other process algebras appear as derived operators. The method iscompositional in the structure of processes and works purely on the syntax of processes. It consists of applying a sequence ofreductions, each of which only takes into account the top-level operator of the process. A reduction transforms a satisfaction problem for a composite process into equivalent satisfaction problems for the immediate subcomponents. Using process variables, systems with underfined subcomponents can be defined, and given an overall requirement to the system,necessary and sufficient conditions on these subcomponents can be found. Hence the process variables make it possible to specify and reason about what are often referred to ascontexts, environments, andpartial implementations. Since reductions are algorithms that work on syntax, they can be considered as forming a bridge between traditional noncompositional model checking and compositional proof systems. 相似文献
94.
This paper describes how vector processing, a supercomputer technique, can be useful in analyzing and evaluating the performance of large-scale nonlinear econometric models. The efficacy of the proposed procedures is illustrated through experiments performed on macromodels developed at the Research Department of the Bank of Italy. 相似文献
95.
Joseph A. Ball J. William Helton 《Mathematics of Control, Signals, and Systems (MCSS)》1992,5(3):233-261
We analyze various aspects of the nonlinear time-invariantHq53ml4t862t77245/xxlarge8734.gif" alt="infin" align="MIDDLE" BORDER="0"> control problem in the discrete-time setting. A recipe is presented that is shown to generate a solution of theH
q53ml4t862t77245/xxlarge8734.gif" alt="infin" align="MIDDLE" BORDER="0"> problem in a precise but weak sense, and which is conjectured to generate a genuine solution in very general circumstances. The recipe involves a version of the Hamilton-Jacobi-Bellman-Isaacs equation from differential game theory. An illustrative example is presented. 相似文献
96.
97.
汽轮机组非平稳运行过程振动数据的时间序列分析 总被引:1,自引:0,他引:1
时间序列的分析方法已经在许多工程领域得到广泛而成功的应用。文中通过对实际电厂运行汽轮机组非平稳过程中轴系振动数据的相关分析 ,对汽轮机组振动数据非平稳时间序列的MA(q)模型的识别和建模进行初步的探讨。为验证MA(q)模型对于汽轮机组非平稳过程中的振动数据分析的有效性 ,分别采用MA(2 )、AR(2 0 )和 3阶多项式回归分析的方法 ,利用现场实测数据进行对比预测实验。实验结果表明利用MA(2 )模型的预测效果明显优于采用AR(p)模型预测方法和传统的多项式回归预测方法的预测结果 ,从而验证采用MA(q)模型对于汽轮机组非平稳运行过程中振动信号分析研究的有效性。 相似文献
98.
P. W. J. Van Eetvelt S. J. Shepherd S. K. Barton 《Wireless Personal Communications》1995,2(1-2):87-96
This paper presents the results of a preliminary investigation into the distribution of peak factors in the QPSK message space for different numbers of carriers with the aim of determining those messages which exhibit a low peak factor relative to a given threshold. A group structure is suggested which associatescosets of 16 messages intoequivalence classes having the same peak power. Algorithms for finding the members of cosets and equivalence classes are given. These messages are then rank ordered by peak power to show how a suitable code could be derived. It appears that allocating just one or two bits of redundancy to such a code will be sufficient to achieve substantial reductions in peak factor. 相似文献
99.
It is shown that for Bi2Sr2CaCu2O8+q54p2087351211/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0"> the quantitative correlation between charge-carrier density, temperature, and oxygen content of the surrounding atmosphere and dopant concentration can be understood with the help of a simple defect model that relies essentially on a significant degree of defect electron trapping. This is consistent with high-temperature Hall effect measurements at different oxygen partial pressures. In addition, electrochemical experiments allow the determination of oxygen diffusion coefficients and their correlation with the defect model. The influences of anisotropy and micro structure are also discussed. The results are interpreted in the context of earlier work on YBa2Cu3O6+q54p2087351211/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0"> and (La, Sr)2CuO4+q54p2087351211/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">. 相似文献
100.
This article studies the problem of data‐driven (DD) fault detection (FD) for linear systems. First, based on the DD realization of kernel representation, new residual generators are designed via a q‐step residual iteration method. Then, it is proved that the proposed residual generators guarantee the stability and L1 performance of the FD error systems, and the presented residual design method is more sensitive to faults than the existing ones constructed directly from available process data. Finally, two simulation examples are provided to verify the effectiveness and advantages of the designed method. 相似文献