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991.
992.
文章针对海洋渔业资源的多种预测算法得到的结果集,提出了以框架的知识表示理论为基础的不确定规则推理预测系统修正算法,利用框架系统KBIF(Knowledge Base in Frame)的知识表示理论与黑板结构、不确定推理相结合对预测算法根据不同环境参数进行多种方式的修正,可以对系统预测结果进行有效的分析,以期得到更好的应用。 相似文献
993.
994.
用速度系数K对振动切削的动态切削过程进行了分析,由试验研究得出:加工硬脆材料时,关键是振动切削中的冲击作用,当K=0.308时,冲击作用最强,切削效果最好,试验结果与理论分析基本一致。 相似文献
995.
本文以水厂控制为背景,研究一类受随机扰动作用、以时滞动态过程为关联约束的大系
统最优控制问题,提出一种自适应双反馈递阶控制方法.它既能象闭环控制那样满足约束条
件、改善性能指标,又能象开环控制那样,计算量小,收敛性好. 相似文献
996.
The emerging multi-layer functional model for network operations decomposes management functions into several layers:Service Management Layer, Network Management Layer, Element Management Layer, andElement Layer. To realize the full benefits of this functional distribution, a reference architecture for operations applications is needed. This architecture should enable flexible placement of functions in computing systems or nodes, enable hiding of the complexities of distribution from applications, and prescribe principles for the specification of application interfaces to facilitate application interoperability. This paper describes such a framework architecture. In this framework, applications are deployed in software units calledbuilding blocks, each of which is independently installed and administered. Building blocks interact via interfaces calledcontracts. A contract is an open interface that is specified according to some principles, such as adherence to standard communication paradigms, separation of engineering aspects from functional aspects, and support for previous interface versions. The infrastructure, called theDistributed Processing Environment (DPE), provides communication and security services that enable building blocks to interact via contracts. The DPE provides access and location transparency to applications. The paper presents details of this architecture framework and an example to illustrate specification of contracts for network management functions. 相似文献
997.
H. Courteney 《Cognition, Technology & Work》2000,2(3):142-153
Cognitive engineering has developed enormously over the last fifteen years. Yet, despite many excellent research projects
and publications, its full potential has not been embraced into mainstream system design. This paper will examine the reasons
for this failure and argue that the problem is not simply inertia or lack of education. There are strong organisational influences
that cause resistance to this particular approach. The discipline itself has characteristics that make it fragile in the modern
corporate structure. In addition, the cognitive engineers themselves are not blameless in the equation. They appear to have
done exactly what they criticise the engineering community for doing: they have packaged their product in a manner that is
not ‘user friendly’ to its target population, not structured to suit its application, and not output in the format required.
Suggestions will be made to rectify the situation: a list of actions is proposed for practising cognitive engineers to make
their product more likely to enjoy widespread uptake. 相似文献
998.
一个商业决策支持系统的设计与实现 总被引:1,自引:0,他引:1
介绍一个商流计划决策支持系统的设计思想和实现方法 ,并讨论开发基于知识的决策支持系统的策略。对决策支持系统中的问题处理系统和模型库的组织提出了新观点 ,给出PPS的功能结构和模型的三层表示法。把组件技术引入到系统设计与实现中来 ,用三层client/server结构来实现DSS。 相似文献
999.
Effect of NaOH on the decomposition of halogenated hydrocarbon by supercritical water oxidation 总被引:1,自引:0,他引:1
Sang-Ha Son Jong-Hwa Kim Hyeon-Chul Lee Chang-Ha Lee 《Korean Journal of Chemical Engineering》2006,23(3):385-390
To protect alloys from corrosion phenomena in the supercritical water oxidation (SCWO) process, the effects of neutralizer
on the conversion and corrosion were investigated. The surface morphologies of all the alloy coupons exposed to 2,4-Dichlorophenol
(2,4-DCP) in the SCWO were significantly changed in microscopic images. The theoretical amount of NaOH as a neutralizer was
calculated under the assumption of complete oxidation of 2,4-DCP. The pre-dosed NaOH in the range of 100% to 300% stoichiometric
amount could not affect significantly the pH value in the SCWO. Moreover, the pH = 7 was not achieved until 700% stoichiometric
amount of NaOH was pre-dosed to the reactor. It is noted that the conversion rate recorded over 99% without oxidant when 800%
of NaOH was pre-dosed into the reactor. In addition, under the addition of H2O2 as an oxidant, the increased amount of NaOH led to the improvement of conversion rate. The pre-dosed NaOH may contribute
to the conversion rate of 2,4-DCP in the SCWO. However, due to low solubility of salt in the SCWO, the fouling problem should
be solved in the SCWO process. 相似文献
1000.
Catalytic ozonation of natural organic matter on alumina 总被引:3,自引:0,他引:3
B. Kasprzyk-Hordern U. Raczyk-Stanisawiak J.
wietlik J. Nawrocki 《Applied catalysis. B, Environmental》2006,62(3-4):345-358
The paper aims to show the potential of catalytic ozonation in the presence of alumina for the removal of natural organic mater from drinking water. An investigation into the efficiency of catalytic ozonation, ozonation by-products formation and their biodegradability was the main goal of the paper. Characterisation of fresh and worn alumina was also conducted. The results clearly indicated the high activity of alumina over a long period of time, which is crucial in water treatment technology. The application of alumina to the ozonation system doubled the efficiency of NOM removal from water when compared to ozonation alone. Furthermore, catalytic ozonation resulted in lower by-products and biodegradable organic carbon formation. 相似文献