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51.
One of the undisputed roles of the Internet is information spreading. However, to this day there is little understanding of the interaction between the way in which information is provided on the Internet and the behavior of different human personality types. This article focuses on the impact of the need for cognition on the desired level of interactivity of a given Website and on web surfing in general. For this experiment, four commercialized Websites were used: (1) flat with no hyperlinks and no time pressure; (2) flat with time pressure; (3) interactive1 with no time pressure; and (4) interactive with time pressure. All of the Websites contained identical information presented in different ways. The relations between need for cognition as a personality variable, time pressure as a situational stressor, the interactivity of the Web site, and several demographic variables were examined on Internet users’ behavior while surfing and on their preferences. One hundred and eighty-two experienced Web surfers took part in the experiment and were randomly assigned to one of the Websites. The number of hyperlinks used while surfing were counted by specially designed software. After surfing, the participants completed questionnaires regarding their satisfaction from the site, their willingness to return to the site, how persuasive the site was, and demographic data. It was predicted that people with high need for cognition would be more experienced in the Internet, use more hyperlinks, and stay longer in the site. People with a low need for cognition were predicted to prefer interactive over linear sites. Results support the preferences of people low in need for cognition of an interactive site. Other predictions were supported only partially. Implementations for Website design and further research are discussed. 相似文献
52.
Effective management of organizational memory (OM) is critical to collaboration and knowledge sharing in organizations. We present a framework for managing organizational memory based on transactive memory, a mechanism of collective memory in small groups. While being effective in small groups, there are difficulties hindering the extension of transactive memory to larger groups. We claim that information technology can be used to help overcome these difficulties. We present a formal architecture for directories of meta-memories required in extended transactive memory systems and propose the use of meta-knowledge to substitute for the lack of tacit group knowledge that exists in small groups. 相似文献
53.
One of the most vociferous criticisms of the Internet has always been that it contributes to loneliness among its users. This study analyses results from the World Internet Project, comprised of representative samples from 13 countries (22,002 participants). Thus creating an exceptional international representative sample. In analyzing those results, we argue that in order to achieve a comprehensive understanding of the Internet’s influence over individuals’ social lives; it is essential to consider the different types of social connections that might be influenced by the Internet. We assess the influence of Internet use over social interactions in separate life domains (e.g. with family members; friends; colleagues). Our analysis confirms that Internet usage can actually enhance the social lives of its users. Qualifications to the research are discussed while highlighting the different life domains in which we found significant correlations between Internet usage and increased social interactions. 相似文献
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Levin A Weiss Y 《IEEE transactions on pattern analysis and machine intelligence》2007,29(9):1647-1654
When we take a picture through transparent glass the image we obtain is often a linear superposition of two images: the image of the scene beyond the glass plus the image of the scene reflected by the glass. Decomposing the single input image into two images is a massively ill-posed problem: in the absence of additional knowledge about the scene being viewed there are an infinite number of valid decompositions. In this paper we focus on an easier problem: user assisted separation in which the user interactively labels a small number of gradients as belonging to one of the layers. Even given labels on part of the gradients, the problem is still ill-posed and additional prior knowledge is needed. Following recent results on the statistics of natural images we use a sparsity prior over derivative filters. This sparsity prior is optimized using the terative reweighted least squares (IRLS) approach. Our results show that using a prior derived from the statistics of natural images gives a far superior performance compared to a Gaussian prior and it enables good separations from a modest number of labeled gradients. 相似文献
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Amir Yair Danilov Claudiu Dolev Danny Kirsch Jonathan Lane John Nita-Rotaru Cristina Olsen Josh Zage David 《Dependable and Secure Computing, IEEE Transactions on》2010,7(1):80-93
This paper presents the first hierarchical Byzantine fault-tolerant replication architecture suitable to systems that span multiple wide-area sites. The architecture confines the effects of any malicious replica to its local site, reduces message complexity of wide-area communication, and allows read-only queries to be performed locally within a site for the price of additional standard hardware. We present proofs that our algorithm provides safety and liveness properties. A prototype implementation is evaluated over several network topologies and is compared with a flat Byzantine fault-tolerant approach. The experimental results show considerable improvement over flat Byzantine replication algorithms, bringing the performance of Byzantine replication closer to existing benign fault-tolerant replication techniques over wide area networks. 相似文献
58.
Studies have shown a connection between the individual personality of the user and the way he or she behaves on line. Today many millions of people around the world are connected by being members of various Internet social networks. Ross et al. (2009) studied the connection between the personality of the individual users and their behavior on a social network. They based their study on the self-reports of users of Facebook, one of the most popular social networks, and measured five personality factors using the NEO-PI-R (Costa & McCrae, 1992) questionnaire. They found that while there was a connection between the personalities of surfers and their behavior on Facebook, it was not strong. This study is based on that of Ross et al. (2009), but in our study the self-reports of subjects, were replaced by more objective criteria, measurements of the user-information upload on Facebook. A strong connection was found between personality and Facebook behavior. Implications of the results are discussed. 相似文献
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