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891.
随着计算、通信和数字媒体技术的发展和渗透,以及嵌入式计算和通信设备的兴起,普适计算作为智能空间的一种新型计算模式,从根本上改变了人们对信息技术的思考,对如何在远程教育中实现普适计算的智能教室进行了研究。智能教室把交互空间的概念引入远程教育系统,远程教育和课堂现场教育的边界被模糊了,教师完全可以同时给现场的学生和远程的学生进行授课。  相似文献   
892.
通过建立深度矢量所在的零空间和目标模型矩阵的零空间之间的关系,开发了一个从目标单视图线性地精确复原其三维位姿的新算法,该算法只需要6个特征点即可实现目标三维位姿的线性重建。理论分析和实验数据表明,该算法具有快速高效、简单实用、抗噪能力较强的优点。  相似文献   
893.
本文主要介绍利用VB6.0串行通信编程的方法,利用MSComm控件实现计算机与计算机间的串口通信。  相似文献   
894.
针对基于Web Service的数据交换系统的具体设计,提出了其中的两个技术关键即"基于WSDL的数据交换标准的制定"以及"可视化界面定义的数据转化方式",探讨了其实现方法。  相似文献   
895.
M.S.  C.  J.A.  B.R. 《Digital Signal Processing》2008,18(6):985-1012
This paper addresses the blind source separation (BSS) problem where the input data are mixtures of sources that are “sparse”—that is each source has zero amplitude for some of the time. It is shown that, under certain conditions, it is possible to separate these sources by the analysis of localised segments of the phase space trajectory where one source dominates rather than applying statistical methods to the whole phase space plot. Results are presented for both simulated data, and thoracic and abdominal ECG data taken from an expectant mother. It is shown that when applied to the ECG data, the proposed technique has a comparable performance to the standard Fast ICA method. For the particular simulated data set, the proposed method gives better results for relatively low noise levels but is less robust than the FastICA for higher noise levels. Subsequently, the potential advantage of using the proposed technique for mixtures of correlated sparse sources is demonstrated. However, for more general sources that are not sparse, the proposed technique in its present form has, as expected, an inferior performance compared to the FastICA technique.  相似文献   
896.
Ensuring model quality is a key success factor in many computer science areas, and becomes crucial in recent software engineering paradigms like the one proposed by model-driven software development. Tool support for measurements and redesigns becomes essential to help developers improve the quality of their models. However, developing such helper tools for the wide variety of (frequently domain specific) visual notations used by software engineers is a hard and repetitive task that does not take advantage from previous developments, thus being frequently forgotten.In this paper we present our approach for the visual specification of measurements and redesigns for Domain Specific Visual Languages (DSVLs). With this purpose, we introduce a novel DSVL called SLAMMER that contains generalisations of some of the more used types of internal product measurements and redesigns. The goal is to facilitate the task of defining measurements and redesigns for any DSVL, as well as the generation of tools from such specification reducing or eliminating the necessity of coding. We rely on the use of visual patterns for the specification of the relevant elements for each measurement and redesign type. In addition, SLAMMER allows the specification of redesigns either procedurally or by means of graph transformation rules. These redesigns can be triggered when the measurements reach a certain threshold.These concepts have been implemented in the meta-modelling tool AToM3. In this way, when a DSVL is designed, it is possible to specify measurements and redesigns that will become available in the final modelling environment generated for the language. As an example, we show a case study in the web modelling domain.  相似文献   
897.
Abstract— This study is intended to explore the legibility and visual fatigue of different age users under various surface treatments and reflectance of electronic paper. Through the method of character‐search task, the results indicated that compared with single types of treatment [anti‐reflection (AR) 0.8%, anti‐glare, 43% haze), the compound treatment of anti‐reflection and anti‐glare (ARC) exhibited the same legibility, and it showed superior properties to effectively reduce visual fatigue. Hence, it is suggested that electronic‐paper manufacturers should choose the compound surface treatment for better visual performance. On the other hand, the findings also validated that enhancing the reflectance of electronic paper to the same level as regular paper (about 80%) is worthy to be practically implemented. Based on the results of this study, electronic‐paper manufacturers can take useful information to fulfill ergonomic requirements on product design.  相似文献   
898.
Abstract— The intent of this study is to investigate some critical factors that affect legibility and visual fatigue while reading on an electronic‐paper display in terms of ergonomics. Anti‐reflection surface treatment, ambient illumination, and bending curvature are taken into account to evaluate their effects by using the method of letter‐search task. The results showed that the surface treatment with high degrees of anti‐reflection significantly improved the legibility and reduces visual fatigue. Thus, electronic‐paper manufacturers may choose a much better surface treatment in order to meet ergonomic demand. In addition, the findings in the present study also indicate that subjects reported less visual fatigue on a bending surface of a visual display unit, in comparison with a plane surface. It is proven that these ergonomic evaluations for electronic paper provide manufactures with useful information to design suitable products for users.  相似文献   
899.
To understand the building design process and to help designers involved, the idea of a research engine has been developed: In this engine cyclic transformations take place between spatial and structural building designs. With this engine, a design process can be studied closely and subjected to improvement, and designers can be supported. To develop the engine, in this paper a part of it is studied, namely the transformation from spatial to structural design, which can be divided into four sub transformations: (1) from spatial design to structural topology; (2) from structural topology to mechanical model; (3) from mechanical model to finite element model; (4) from finite element model to design recommendations. For the first sub transformation, two different techniques are presented: Spatial–Structural Transformation Rules and Element Selection. For the second sub transformation, also two techniques are presented: Element Approach and System Approach. Where possible, data models in EXPRESS and process models in IDEF0 are used. For the third and fourth sub transformation, new procedures have been developed using data models in EXPRESS. To test the data and process models for all four sub transformations, a simplified two-storey building, derived from a real six-storey apartment building, is used as case study. It can be concluded that the developed sub transformations function well, related to their application in the research engine, and that their development raises new research questions that have to be solved in the near future.  相似文献   
900.
In order to ensure the security and reliability of Web application, the testing of Web application is one of the most effective methods. This work regards a Web application as the composition of different interactive Logical Components (LCs). We combine LCs with agent to assist to automatic generate test cases for testing Web applications. From Pages-Flow-Diagram (PFD) of Web application under test, this research successively partitions Web applications into LCs, at different levels of abstraction, each of which is composed of Web pages and other LCs. We use an automaton to model each LC, and use compositions of automata to model interaction of LCs. Our approach supports concurrent access and interaction between LCs. It avoids the state space explosion problem effectively. It also enhances the reuse of component interactions and overcomes differences in actions between LCs by using an agent as a coordinator.  相似文献   
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