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991.
Service orientation has been a major buzz-word in recent years. While the buzz is on a decline, organizations are slowly, but steadily moving towards service oriented designs. However, service orientation turns out to be as much of a managerial challenge as of a technical one. The most important complexity drivers in the service oriented design of information systems seem to be (a) inconsistent design goals of stakeholders and (b) the pursuit of exhaustive service orientation coverage. This research focuses on the following two questions: (1) What are the characteristics of successful implementations of service oriented information systems, and (2) what are the critical success factors influencing, driving and/or determining these characteristics? Data of an empirical analysis is used to test a set of cause-effect relationship hypotheses based on nine latent variables. In the core of this model we differentiate the variables ??overall service orientation infrastructure success?? and ??service orientation project success??. The hypothesized interrelationships between the nine variables lead to a causal model which is proven to hold.  相似文献   
992.
993.
In recent years, manufacturing companies and service providers have moved towards offering customer-specific problem solutions. These integrated bundles usually consist of hardware, software, and service components and are called product service systems (PSS) or hybrid products. Since the success of the resulting solution depends on the understanding of all requirements, requirements engineering (RE) has become a key factor. The article analyzes the state of the art of RE for PSS based on an extensive literature review in the domains of product-, software-, and service engineering. For this, criteria are derived from the characteristics of PSS and from the task area of RE in the life cycle of PSS. Based on these criteria we analyze the most established RE approaches for their suitability for PSS. An important finding is that integrated/interdisciplinary approaches for RE are missing. Moreover, the maturity of RE approaches in the three domains varies significantly. All analyzed approaches heavily rely on concepts and solution characteristics of their own domain so that a transfer to other domains is hardly possible. This literature review lays the foundation for successful RE for PSS and especially for future research aiming at combining and integrating RE approaches and models of product-, software-, and service engineering. Such requirement models could connect concepts of single domains and enable an integrated and seamless RE for PSS.  相似文献   
994.
We present the results of a novel micro-beam deflection test used to investigate the static and dynamic mechanical behavior of submicron-thick metal films. The method demonstrated in this study allows researchers to observe the motion of micro and nano-scale thin films responding to electrostatic loads, by means of laser reflection measurements at frequency rates of up to 500 Hz. Researchers fabricated a supporting frame and a novel triangular shaped “paddle” beam designed to provide uniform plane stress distribution while undergoing deflection. A simple geometric calculation, based on cantilever deflection, enabled the degree of strain to be determined, which in turn provided the Young’s modus for aluminum film of a given thickness. We also studied the dynamic behavior using the dynamic frequency response of the beam, generated by electrostatic forces under various loads and vacuum pressure conditions. Our results showed that air damping has a significant influence on the free damping behavior of specimens, and only a minor influence on damping frequency. We determined the loss angle and frequency using sweep frequency and free damping methods, which were very consistent with paddle resonant frequencies. The loss angle obtained from a simple silicon micro-beam was 2.001 × 10−4°using the free damping method and 2.23 × 10−4°using the sweep frequency method. The dynamic response loss mechanism measured in this experiment provides incentive for the further study of grain boundary motion and dislocation motion in thin films.  相似文献   
995.
In this work, we initiated the effort of developing a so-called water microflotilla, which was capable of moving on a water surface. We explored its design, fabrication, propulsion, and motions in straight and circular channels. A water microflotilla comprised five microboats connected with a Nylon rope, and was fabricated using ultra-violet lithographic techniques. It was actuated by the difference between fore-and-aft surface tensions. The water microflotilla was tested in three straight and one circular channels at water levels of 3, 6 and 9?mm, respectively. In all the tests, the microflotilla moved like a rigid object, and no collisions were observed between neighboring microboats. Travel distances were above 0.44?m, and average speeds varied from 40.2 to 103.2?mm/s. Both the travel distances and the average speeds were found to increase with the increasing water depth and channel width. The two ends of the microflotilla had direct contact with the outer sidewall of the circular channel during a circular motion. The support forces of the outer sidewall at these contact points provided the centripetal force needed for the circular motion. Compared with a single microboat, such a microflotilla can be potentially employed to transport a large amount of supply in small-scale fluidic applications.  相似文献   
996.
As an effective technique to manage and explore large scale of video collections, personalized video search has received great attentions in recent years. One of the key problems in the related technique development is how to design and evaluate the similarity measures. Most of the existing approaches simply adopt traditional Euclidean distance or its variants. Consequently, they generally suffer from two main disadvantages: (1) low effectiveness—retrieval accuracy is poor. One of main reasons is that very little research has been carried out on designing an effective fusion scheme for integrating multimodal information (e.g., text, audio and visual) from video sequences and (2) poor scalability—development process of the video similarity metrics is largely disconnected from that of the relevant database access methods (indexing structures). This article reports a new distance metric called personalized video distance to effectively fuse information about individual preference and multimodal properties into a compact signature. Moreover, a novel hashing-based indexing structure has been designed to facilitate fast retrieval process and better scalability. A set of comprehensive empirical studies have been carried out based on two large video test collections and carefully designed queries with different complexities. We observe significant improvements over the existing techniques on various aspects.  相似文献   
997.
This paper presents a knowledge exchange framework that can leverage the interoperability among semantically heterogeneous learning objects. With the release of various e-Learning standards, learning contents and digital courses are easy to achieve cross-platform sharing, exchanging, and even reorganizing. However, knowledge sharing in semantic level is still a challenge due to that the learning materials can be presented in any form, such as audios, videos, web pages, and even flash files. The proposed knowledge exchange framework allows users to share their learning materials (also called “learning objects”) in semantic level automatically. This framework contains two methodologies: the first is a semantic mapping between knowledge bases (i.e. ontologies) which have essentially similar concepts, and the second is an ontology-based classification algorithm for sharable learning objects. The proposed algorithm adopts the IMS DRI standard and classifies the sharable learning objects from heterogeneous repositories into a local knowledge base by their inner meaning instead of keyword matching. Significance of this research lies in the semantic inferring rules for ontology mapping and learning objects classification as well as the full automatic processing and self-optimizing capability. Focused on digital learning materials and contrasted to other traditional technologies, the proposed approach has experimentally demonstrated significantly improvement in performance.  相似文献   
998.
服务发现的主要过程就是对服务请求和己注册服务间IOPE进行匹配.提出一种新的服务发现框架,以及改进的综合相似度算法.综合考虑语义距离,本体树中概念的深度、密度,以及信息共享来计算服务的相似度.将服务发现过程分为过滤和排序两阶段,并对服务的各参数分别采用更适合的相似度计算方法.将用户给出的服务输入用于最后的排序阶段,以减...  相似文献   
999.
冯诚  李治军  姜守旭 《计算机工程与设计》2011,32(5):1521-1526,1530
具有短距离通信能力的车载设备的改进和短距离微波通信授权频谱的分配推动了智能交通系统应用的发展,促进了车用自组织网络(VANET)的研究。对于VANET上的应用数据分发是各类应用实现的基础,同时数据聚合又是实现数据分发的关键技术。介绍了VANET的概念和网络构架,给出了当前VANET上的一些典型应用;详细阐述了VANET上的数据分发的基本结构,并对数据聚合算法的研究现状进行了详细的分析和比较;最后总结并展望了VANET上的数据聚合在未来一段时间的研究重点。  相似文献   
1000.
PCB检测中图像分割技术研究   总被引:2,自引:0,他引:2  
光学检测是进行印刷电路板(PCB)装配质量检验的重要手段,应用图像分割技术可以提取PCB中的目标物以进行检测。针对PCB图像分割,提出一种基于改进量子遗传算法的图像分割方法。该方法将基于阈值的图像分割方法转化为阈值优化问题,通过改进量子遗传算法的计算实现最优图像分割阈值的求取。仿真结果验证了该方法的可行性。  相似文献   
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