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41.
针对溢洪道设计中经常遇到的方案优选问题,提出将多因素、多层次模糊优选理论引入溢洪道的设计选型工作中。对影响因素复杂、确定隶属函数主观因素较强的情况,引入因素的优先关系法来确定优选矩阵的隶属度,这样减少了确定隶属函数的人为影响,通过此优选模型利用影响溢洪道选型的主要因素对多种溢洪道设计型式进行了多级模糊综合优选决策,得到了比较理想的决策结果,为溢洪道设计选型提供了新的思路。 相似文献
42.
Although word stress has been hailed as a powerful speech-segmentation cue, the results of 5 cross-modal fragment priming experiments revealed limitations to stress-based segmentation. Specifically, the stress pattern of auditory primes failed to have any effect on the lexical decision latencies to related visual targets. A determining factor was whether the onset of the prime was coarticulated with the preceding speech fragment. Uncoarticulated (i.e., concatenated) primes facilitated priming. Coarticulated ones did not. However, when the primes were presented in a background of noise, the pattern of results reversed, and a strong stress effect emerged: Stress-initial primes caused more pruning than non-initial-stress primes, regardless of the coarticulatory cues. The results underscore the role of coarticulation in the segmentation of clear speech and that of stress in impoverished listening conditions. More generally, they call for an integrated and signal-contingent approach to speech segmentation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
P. Remagnino Author Vitae Author Vitae G.A. Jones Author Vitae 《Pattern recognition》2004,37(4):675-689
Latest advances in hardware technology and state of the art of computer vision and artificial intelligence research can be employed to develop autonomous and distributed monitoring systems. The paper proposes a multi-agent architecture for the understanding of scene dynamics merging the information streamed by multiple cameras. A typical application would be the monitoring of a secure site, or any visual surveillance application deploying a network of cameras. Modular software (the agents) within such architecture controls the different components of the system and incrementally builds a model of the scene by merging the information gathered over extended periods of time. The role of distributed artificial intelligence composed of separate and autonomous modules is justified by the need for scalable designs capable of co-operating to infer an optimal interpretation of the scene. Decentralizing intelligence means creating more robust and reliable sources of interpretation, but also allows easy maintenance and updating of the system. Results are presented to support the choice of a distributed architecture, and to prove that scene interpretation can be incrementally and efficiently built by modular software. 相似文献
44.
针对电动汽车充电行为不确定性问题,建立了基于出行链理论的电动汽车出行及电池电量变化模型,提出了引入马尔可夫决策过程(Markov decision processes, MDP)的电动汽车用户充电行为分析方法。该方法将用户充电行为作为马尔可夫决策集,根据车辆在各区域间的转移概率构造状态转移矩阵,设置用户满意度指标作为决策过程报酬函数,通过求解有限阶段总报酬准则得到电动汽车用户在每个决策点处的最优充电决策。算例部分根据抽取电动汽车特征量数据进行马尔可夫决策过程仿真,得出充电负荷的时间与空间分布情况,通过与传统蒙特卡洛方法进行对比表明该文所提方法可以较好地模拟用户整个出行过程中的充电行为,反映充电需求的时空分布特点;同时,分析了不同区域、不同停车时长情况下电动汽车的不同充电行为,能够为电动汽车充电桩的规划建设提供参考。 相似文献
45.
Demarcating distribution area of goods is often guided by the rule of thumb by business proprietors.However,this method seems to be unsuitable when the demand points increase to a certain large extent.The present work attempted to convert the problem of distribution area demarcation into a localized problem of warehouseing and networking,and tried to establish district-based planning mode based on location based heuristic (LBH).Two methods were used in this study:1) the manual method to construct the mathematical model and conduct simulation;2) the automatic method using TransCAD software of geographical information system (GIS) for simulation.By comparing the effects of the two methods,the research provides theoretical support for business proprietors to demarcate the distribution area rationally with the application of GIS system.The results show that GIS has very good graphics construction function to replace complex text,and the automatic demarcating mode with human-machine interaction provides a good business decision-making support. 相似文献
46.
It is argued that classical measures of computer system performance, for example mean response time, are inadequate in the context of fault-tolerant system design. Alternative, perception-based measures are proposed and theorems established describing their properties. Focus is directed upon the homogeneous M/M/m system in which total processor power is constrained by budget and processors are subject to failure and repair. A numerical technique for extracting both classical and perception-based measures from the associated two-dimensional Markov process is offered, along with bounds on time and space required for its execution. It is seen that the perception-based approach to system design can call for twice as many processors as the classical approach. 相似文献
47.
The spatially varying coefficient process model is a nonstationary approach to explaining spatial heterogen-eity by allowing coefficients to vary across space. In this article, we develop a methodology for generalizing this model to accommodate geographically hierarchical data. This article considers two-level hierarchical structures and allow for the coefficients of both low-level and high-level units to vary over space. We assume that the spatially varying low-level coefficients follow the multivariate Gaussian process, and the spatially varying high-level coefficients follow the multivariate simultaneous autoregressive model that we develop by extending the standard simultaneous autoregressive model to incorporate multivariate data. We apply the proposed model to transaction data of houses sold in 2014 in a part of the city of Los Angeles. The results show that the proposed model predicts housing prices and fits the data effectively. 相似文献
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区域水资源短缺风险决策研究 总被引:5,自引:0,他引:5
为选择区域水资源短缺风险管理方案,在水资源短缺风险分析和评价的基础上,研究了水资源短缺风险决策的期望益损值法,最后对包括北京和天津在内的首都圈进行水资源短缺风险决策.结果表明,要彻底解决首都圈的水资源短缺问题,南水北调具有重要的作用,在南水北调存在的情况下,其他水资源管理措施的投资规模应该适度,这样才能保证区域社会经济的可持续发展和区域水资源的可持续利用. 相似文献