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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
971.
雨季施工时基坑工程受暴雨入渗以及邻近河流水位涨落耦合作用,容易发生渗透破坏事故。基于裘布依(Dupuit)假定建立分层地基地下水耦合渗流方程,以此确定在暴雨入渗以及河流水位涨落耦合作用下基坑周边地下水位。同时基于渗流-应力耦合分析理论与Midas分析软件,以某基坑工程实例为研究对象,建立基坑工程渗流-应力耦合分析模型,对基坑工程渗流破坏现象进行分析研究,由此得出了对其它工程有重要参考价值的结论。 相似文献
972.
973.
水利水电工程通航技术研究进展 总被引:1,自引:0,他引:1
随着我国水利水电工程向具有供水、防洪、发电、通航等多目标开发方向的发展,高坝通航技术得到了迅猛发展。总结了通航建筑物船闸及升船机的技术研究进展,特别是具有国际领先水平的船闸输水形式及阀门防空化新技术,湿运全平衡钢丝绳卷扬提升式垂直升船机、齿轮齿条爬升式升船机和水力浮动式升船机新技术。我国高坝通航升船机及船闸建设水平已跃居世界前列。 相似文献
974.
运用改进西原蠕变模型,建立了能反映蠕变全过程的非线性粘弹塑性蠕变模型,结合渗流力学理论得出了平面应变情况下的流固耦合方程。通过算例数值计算对降雨条件下土质坡体特征点的水平和垂直位移进行了分析,结果与现场调查相符。计算结果表明,土质边坡在降雨入渗初期位移变化较大,且水平位移比垂直位移大;降雨入渗具有迟滞效应,雨水渗流主要集中在坡体浅层,加强坡面防护很关键。 相似文献
975.
Jan Wassenberg 《Software》2012,42(9):1095-1106
This report introduces a new lossless asymmetric single instruction multiple data codec designed for extremely efficient decompression of large satellite images. A throughput in excess of 3GB/s allows decompression to proceed in parallel with asynchronous transfers from fast block devices such as disk arrays. This is made possible by a simple and fast single instruction multiple data entropy coder that removes leading null bits. Our main contribution is a new approach for vectorized prediction and encoding. Unlike previous approaches that treat the entropy coder as a black box, we account for its properties in the design of the predictor. The resulting compressed stream is 1.2 to 1.5 times as large as JPEG‐2000, but can be decompressed 100 times as quickly – even faster than copying uncompressed data in memory. Applications include streaming decompression for out of core visualization. To the best of our knowledge, this is the first entirely vectorized algorithm for lossless compression. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
976.
I‐Ching Hsu 《Software》2012,42(10):1211-1227
Web 2.0 Mashups offer entirely new opportunities for context‐aware application (CAA) developers by integrating Web 2.0 technologies to facilitate interoperability among heterogeneous context‐aware systems. From a software engineering perspective, a visualized approach for Web 2.0‐based CAA modeling is crucial. Current CAA development, however, cannot provide a conceptual model for Web 2.0‐based CAA. Therefore, the development efficiency and potential for reuse are decreased. The UML is a general purpose modeling language with potential for use in many application domains. However, UML often lacks elements needed to model concepts in specific domains, such as Web 2.0‐based CAA modeling. To address the above issues, this study presents the Web 2.0‐based CAA UML profile, a UML profile for modeling Web 2.0‐based CAA. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
977.
《Behaviour & Information Technology》2012,31(1-2):154-159
Abstract This article defines a quantitative goal that is cheap to measure for the usability of a business application system for casual users. The article also describes a cost-effective method for attaining the goal. The goal is to eliminate all user interface disasters (UIDs) in a given system. UIDs are usability problems that seriously annoy users, or prevent them from accomplishing their work without help from a human being. The method consists of series of simple user tests without audio or video recording, and with little analysis after each user test. The article concludes by describing Baltica's results of applying the method to a medium-size business application for casual users. 相似文献
978.
Software modernization is critical for organizations that need cost-effective solutions to deal with the rapid obsolescence of software and the increasing demand for new functionality. This paper presents the XIRUP modernization methodology, which proposes a highly iterative process, structured into four phases: preliminary evaluation, understanding, building and migration. This modernization process is feature-driven, component-based, focused on the early elicitation of key information, and relies on a model-driven approach with extensive use of experience from the previous projects. XIRUP has been defined in the European IST project MOMOCS, which has also built a suite of support tools. This paper introduces the process using a case study that illustrates its activities, related tools and results. The discussion highlights the specific characteristics of modernization projects and how a customized methodology can take advantage of them. 相似文献
979.
Sotirios Liaskos Shakil M. Khan Marin Litoiu Marina Daoud Jungblut Vyacheslav Rogozhkin John Mylopoulos 《Information Systems》2012
Customizing software to perfectly fit individual needs is becoming increasingly important in information systems engineering. Users want to be able to customize software behavior through reference to terms familiar to their diverse needs and experience. We present a requirements-driven approach to behavioral customization of software systems. Goal models are constructed to represent alternative behaviors that users can exhibit to achieve their goals. Customization information is then added to restrict the space of possibilities to those that fit specific users, contexts, or situations. Meanwhile, elements of the goal models are mapped to units of source code. This way, customization preferences posed at the requirements level are directly translated into system customizations. Our approach, which we apply to an on-line shopping cart system and an automated teller machine simulator, does not assume adoption of a particular development methodology, platform, or variability implementation technique and keeps the reasoning computation overhead from interfering with the execution of the configured application. 相似文献
980.