全文获取类型
| 收费全文 | 662篇 |
| 免费 | 51篇 |
| 国内免费 | 19篇 |
专业分类
| 电工技术 | 10篇 |
| 综合类 | 26篇 |
| 化学工业 | 22篇 |
| 金属工艺 | 13篇 |
| 机械仪表 | 46篇 |
| 建筑科学 | 7篇 |
| 矿业工程 | 2篇 |
| 能源动力 | 11篇 |
| 轻工业 | 4篇 |
| 水利工程 | 3篇 |
| 石油天然气 | 4篇 |
| 武器工业 | 2篇 |
| 无线电 | 62篇 |
| 一般工业技术 | 37篇 |
| 冶金工业 | 2篇 |
| 原子能技术 | 4篇 |
| 自动化技术 | 477篇 |
出版年
| 2024年 | 4篇 |
| 2023年 | 10篇 |
| 2022年 | 7篇 |
| 2021年 | 14篇 |
| 2020年 | 14篇 |
| 2019年 | 16篇 |
| 2018年 | 11篇 |
| 2017年 | 20篇 |
| 2016年 | 19篇 |
| 2015年 | 30篇 |
| 2014年 | 27篇 |
| 2013年 | 44篇 |
| 2012年 | 36篇 |
| 2011年 | 53篇 |
| 2010年 | 15篇 |
| 2009年 | 38篇 |
| 2008年 | 53篇 |
| 2007年 | 47篇 |
| 2006年 | 39篇 |
| 2005年 | 27篇 |
| 2004年 | 28篇 |
| 2003年 | 22篇 |
| 2002年 | 18篇 |
| 2001年 | 22篇 |
| 2000年 | 15篇 |
| 1999年 | 12篇 |
| 1998年 | 8篇 |
| 1997年 | 9篇 |
| 1996年 | 14篇 |
| 1995年 | 6篇 |
| 1994年 | 13篇 |
| 1993年 | 8篇 |
| 1992年 | 4篇 |
| 1991年 | 2篇 |
| 1990年 | 4篇 |
| 1989年 | 6篇 |
| 1988年 | 4篇 |
| 1987年 | 2篇 |
| 1986年 | 3篇 |
| 1985年 | 4篇 |
| 1984年 | 1篇 |
| 1983年 | 2篇 |
| 1981年 | 1篇 |
排序方式： 共有732条查询结果，搜索用时 15 毫秒
91.
We review the literature on approximate dynamic programming, with the goal of better understanding the theory behind practical algorithms for solving dynamic programs with continuous and vector-valued states and actions and complex information processes. We build on the literature that has addressed the well-known problem of multidimensional (and possibly continuous) states, and the extensive literature on model-free dynamic programming, which also assumes that the expectation in Bellman’s equation cannot be computed. However, we point out complications that arise when the actions/controls are vector-valued and possibly continuous. We then describe some recent research by the authors on approximate policy iteration algorithms that offer convergence guarantees (with technical assumptions) for both parametric and nonparametric architectures for the value function. 相似文献
92.
With the increasing number of available XML documents, numerous approaches for retrieval have been proposed in the literature. They usually use the tree representation of documents and queries to process them, whether in an implicit or explicit way. Although retrieving XML documents can be considered as a tree matching problem between the query tree and the document trees, only a few approaches take advantage of the algorithms and methods proposed by the graph theory. In this paper, we aim at studying the theoretical approaches proposed in the literature for tree matching and at seeing how these approaches have been adapted to XML querying and retrieval, from both an exact and an approximate matching perspective. This study will allow us to highlight theoretical aspects of graph theory that have not been yet explored in XML retrieval. 相似文献
93.
94.
近似串匹配是生物信息学、文本检索、信号处理等领域的一个基础问题,如何提高近似串匹配的速度一直都是研究的关键问题。提出一种新的在大文本库中快速查找近似匹配的无损过滤算法。为保证在大文本库中的匹配速度,本算法使用了查询速度较快的q-gram索引。为通过提高过滤算法的过滤效率达到提升算法整体性能的目的,详细分析了含有匹配串的文本区域,提取了一些基于尾匹配q-gram特征的新过滤条件,然后用这些特征优化了过滤算法的过滤标准。实验数据表明,新过滤条件有效地提高了算法的过滤效率,提升了算法的整体性能。结果显示新算法适合各种匹配错误率下的近似匹配,算法的通用性较强。 相似文献
95.
Many efficient exact branch and bound maximum clique solvers use approximate coloring to compute an upper bound on the clique number for every subproblem. This technique reasonably promises tight bounds on average, but never tighter than the chromatic number of the graph.Li and Quan, 2010, AAAI Conference, p. 128–133 describe a way to compute even tighter bounds by reducing each colored subproblem to maximum satisfiability problem (MaxSAT). Moreover they show empirically that the new bounds obtained may be lower than the chromatic number.Based on this idea this paper shows an efficient way to compute related “infra-chromatic” upper bounds without an explicit MaxSAT encoding. The reported results show some of the best times for a stand-alone computer over a number of instances from standard benchmarks. 相似文献
96.
Approximate dynamic programming (ADP) relies, in the continuous-state case, on both a flexible class of models for the approximation of the value functions and a smart sampling of the state space for the numerical solution of the recursive Bellman equations. In this paper, low-discrepancy sequences, commonly employed for number-theoretic methods, are investigated as a sampling scheme in the ADP context when local models, such as the Nadaraya–Watson (NW) ones, are employed for the approximation of the value function. The analysis is carried out both from a theoretical and a practical point of view. In particular, it is shown that the combined use of low-discrepancy sequences and NW models enables the convergence of the ADP procedure. Then, the regular structure of the low-discrepancy sampling is exploited to derive a method for automatic selection of the bandwidth of NW models, which yields a significant saving in the computational effort with respect to the standard cross validation approach. Simulation results concerning an inventory management problem are presented to show the effectiveness of the proposed techniques. 相似文献
97.
98.
99.
目前在智能领域中对Vague集的研究已越来越广泛与深入,并运用于决策问题中,有学者已把Vague集用于多评价指标的模糊决策中,但其决策方法在某些时候却难以得到目标。为此,本文提出了一个基于Vague集模糊推理的多评价指标模糊决策方法。在这个方法中,从基于Vague集的模糊推理的观点来看待模糊决策问题。将评价指标和候选方案之间的关系用一组基于Vague集的推理规则来表示,将决策者的要求用一组Vague集来表示,经过模糊推理等过程最后得到决策结果。然后还给出了一个实例说明这种多评价指标模糊决策方法。这个基于Vague集模糊推理的多评价指标模糊决策方法的提出为决策系统提供了一个有用的工具。 相似文献
100.
缺电损失最小化减负荷算法的研究 总被引：1，自引：0，他引：1
在满足安全稳定限制的情况下,建立了寻求缺电损失最小的负荷减载模型和算法,以解决系统供电不足时的减负荷问题.该模型是具有等式和不等式约束的函数极值问题,属于最优潮流模型.该算法是在控制变量空间寻优的改进近似规划法：从初始可行的运行点开始,通过计算系统的状态变量对控制变量的灵敏度,将系统的目标函数和约束条件线性化,进行有效约束的筛选,以线性规划修正控制变量,进而解算潮流得到新的可行运行点.通过迭代收敛到最优解.并以IEEE-14节点系统和IEEE-30节点系统为试算系统,验证了该算法的有效性. 相似文献