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71.
钢轨表面擦伤检测是保障铁路运输安全的重要手段之一。应用图像处理和模式识别技术来处理钢轨数字图像,检测并定位擦伤区域是一种可行且发展迅速的研究手段。课题组在前期工作中提出了一种鲁棒实时的钢轨表面擦伤检测算法,该算法首先对钢轨图像进行灰度对比度增强,在此基础上定位可疑擦伤区域并进行判定。算法对于常规擦伤图像具有较高的检测性能,但对于钢轨图像包含多处擦伤且擦伤区域灰度值差异较大的情况,往往造成漏检。针对原算法的不足,提出了一种基于空间滤波的钢轨表面擦伤检测改进算法,该算法对原算法检测到的擦伤区域进行钢轨灰度图均值填充,并对填充后的图像进行二次检测,在重新生成的灰度对比度图中,原检测图像中灰度值不明显的擦伤区域的灰度对比度值得到增强,从而增加了检出的可能性。经实验结果验证,改进算法具有较高的检测性能:在总的时间耗费没有明显增加的情况下,检测的平均准确率为90.8%,平均漏检率为4.0%,较原算法有较大改善。  相似文献   
72.
随着我国经济进入加速转型期,市场机制在劳动力资源配置中作用不断加大,我国企业工资水平宏观调控体系机制已成为繁复的工程系统。本文运用广义数学期望算法构建企业工资水平宏观调控评价体系,从经济发展,社会和谐,生活协调三个方面对中国企业工资水平宏观调控体系展开综合评价,分析存在的问题,为优化和完善中国企业工资水平宏观调控机制提供决策依据和政策建议。  相似文献   
73.
Context: The emergence of the long-tail in the market of software applications is shifting the role of end-users from mere consumers to becoming developers of applications addressing their unique, personal, and transient needs. On the Web, a popular form of such applications is called mashup, built out of the lightweight composition of Web APIs (reusable software components delivered as a service through the Web). To enable end-users to build mashups, there is a key problem that must be overcome: End-users lack programming knowledge as well as the interest to learn how to master the complex set of Web technologies required to develop mashups. End-User Development (EUD) is an emerging research field dealing with this type of problems. Its main goal is to design tools and techniques facilitating the development of software applications by non-programmers.Objective: The paper describes the design and evaluation of NaturalMash, an innovative EUD tool for mashups (a mashup tool). NaturalMash aims at enabling non-professional users without any knowledge of programming languages and skills to create feature-rich, interactive, and useful mashups.Methods: The design of NaturalMash adopts a formative evaluation approach, and has completed three design and evaluation iterations. The formative evaluations utilize usability testing, think aloud protocol, questionnaires, observation, and unstructured interviews. Additionally, we compare the expressive power of naturalmash with the state-of-the-art mashup tools.Results: The results from the formative evaluations helped us identify important usability problems. From an assessment point of view, the results were promising and sggested that the proposed tool has a short and gentle learning curve in a way that even non-programmers are able to rapidly build useful mashups. Also, the comparative evaluation results showed that NaturalMash offers a competitive level of expressive power compared with existing mashup tools targeting non-programmers.Conclusion: As the evaluation results indicate, NaturalMash provides a high level of expressive power while it is still highly usable by non-programmers. These suggest that we have successfully achieved the objective of the proposed tool, distinguishing it from existing mashup tools that are either too limited or highly specialized for non-professional users.  相似文献   
74.
Objective: We present a new non-photorealistic rendering method to render 3D scenes in the form of pencil-like sketches.Methods: This work is based on the observation that the dynamic feedback mechanism involving the human visual system and the motor control of the hand collectively generates the visual characteristics unique to hand-drawn sketches. At the heart of our approach is a trajectory planning and tracking algorithm that generate the sketch in multiple layers using a dynamic pen model. On each layer, a set of target strokes are generated from the silhouette lines, edges, and shaded regions which serve as the target trajectory for a closed-loop dynamic pen model. The pen model then produces the rendered sketch, whose characteristics can be adjusted with a set of trajectory and tracking parameters. This process continues in several layers until the tonal difference between the sketch and the original 3D render is minimized.Results: We demonstrate our approach with examples that are created by controlling the parameters of our sketch rendering algorithms.Conclusion: The examples not only show typical sketching artifacts that are common to human-drawn sketches but also demonstrate that it is capable of producing multiple sketching styles.  相似文献   
75.
Objectives: OpenMusic (OM) is a domain-specific visual programming language designed for computer-aided music composition. This language based on Common Lisp allows composers to develop functional processes generating or transforming musical data, and to execute them locally by demand-driven evaluations. As most historical computer-aided composition environments, OM relies on a transformational declarative paradigm, which is hard to conciliate with reactive data-flow (an evaluation scheme more adequate to the development of interactive systems). We propose to link these two evaluation paradigms in the same and consistent visual programming framework.Methods: We establish a denotational semantics of the visual language, which gives account for its demand-driven evaluation mechanism and the incremental construction of programs. We then extend this semantics to enable reactive computations in the functional graphs.Results: The resulting language merges data-driven executions with the existing demand-driven mechanism. A conservative implementation is proposed.Conclusions: We show that the incremental construction of programs and their data-driven and demand-driven evaluations can be smoothly integrated in the visual programming workflow. This integration allows for the propagation of changes in the programs, and the evaluation of graphically designed functional expressions as a response to external events, a first step in bridging the gap between computer-assisted composition environments and real-time musical systems.  相似文献   
76.
ObjectiveThis paper proposed a new approach for inner-knuckle-print (IKP) recognition. In traditional IKP recognition systems, the region of interest (ROI) is extracted from the image of the whole hand and the directions of the fingers being imaged are not restricted. The result maybe incorrect because that the shape and surface of the fingers may vary greatly. Moreover, if the direction of the finger being imaged is not restricted, there may be severe rotation transform between intra-class IKPs. To overcome these drawbacks, we develop a new data acquisition scheme as well as an efficient personal authentication algorithm.MethodsThe new scheme is designed to capture the image of the inner surface of the middle knuckles of the middle and ring fingers. The fingers being imaged are kept horizontal with two pegs, so that the rotation angle between different images obtained from the same hand can be minimized. The new personal authentication algorithm consists of the next four steps. Firstly, two regions of interest (ROI), each of which contains the inner surface of a knuckle, are cropped from the original image. Secondly, line features are extracted from the ROIs based on the combination of Gabor filtering and derivative line detection method. Then, binary line images are matched by using a cross-correlation-based method. Finally, the input data is classified through score level fusion.ResultsTo evaluate the proposed IKP recognition system, a finger image database which includes 2000 images from 100 volunteers is established. The images are captured on two separate occasions, at an interval of around two months. Most of the volunteers are not familiar with the image acquisition process. The experimental results show that the proposed system achieves high recognition rate and it works in real time. Moreover, the proposed line feature extraction method outperforms traditional Gabor filter based line detection method and derivative line detection method in accuracy.ConclusionThe proposed IKP system is robust and accurate. It may promote the application and popularization of IKP recognition.  相似文献   
77.
ObjectiveCreate a visual mobile end user development framework, named Puzzle, which allows end users without IT background to create, modify and execute applications, and provides support for interaction with smart things, phone functions and web services.MethodsDesign of an intuitive visual metaphor and associated interaction techniques for supporting end user development in mobile devices with iterative empirical validation.ResultsOur results show that the jigsaw is an intuitive metaphor for development in a mobile environment and our interaction techniques required a limited cognitive effort to use and learn the framework. Integration of different modalities and usage of smart things was relevant for users.ConclusionPuzzle has addressed the main objective. The framework further contributes to the research on mobile end user development in order to create an incentive for users to go beyond consuming content and applications to start creating their own applications.PracticeUsage of a mobile end user development environment has the potential to create a shift from the conventional few-to-many distribution model of software to a many-to-many distribution model. Users will be able to create applications that fit their requirements and share their achievements with peers.ImplicationsThis study has indicated that the Puzzle visual environment has the potential to enable users to easily create applications and stimulate exploration of innovative scenarios through smartphones.  相似文献   
78.
对蓝光激发叶绿素的荧光光谱进行了分析,讨论了叶绿素荧光光谱的来源,采用调制式470nm绿光LED激发叶绿素,制成叶绿素荧光光谱仪,线性范围0—100μg/L,检出限0.1μg/L,该方法快速、灵敏、有很好的特异性.  相似文献   
79.
在1990年12月以前,建筑作品是作为绘画、图形和雕塑作品获得版权保护的.但是建筑本身被认为是一种实用物品,因而不受版权的保护.然而在1989年3月1日,美国加入《伯尔尼公约》.为了履行公约义务,美国国会通过了《1990年建筑作品版权保护法》(简称AWCPA),对《1976年版权法》进行了相应的修正,建筑作品作为独立的一类作品受版权法的保护,拓宽了建筑作品的保护范围,对建筑作品侵权的认定标准也发生变化.  相似文献   
80.
通过SPSS相关性分析了我国的房地产周期对金融稳定的影响程度.针对我国现在存在的问题,提出了加强房地产信贷监管力度、控制房地产投资与信贷投入比、强化土地储备贷款的管理、规范个人住房贷款业务和加强商业银行房地产金融人才的培养等五个方面的建议,来减少房地产周期波动对金融稳定的影响.  相似文献   
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