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991.
The relationship between video gameplay, video game genre preference, personality, and GPA was investigated in an online correlational study with university students. In addition to administering self-report measures of GPA and personality, we asked three different questions regarding styles of video gameplay. The first asked the average time spent playing video games per week (habitual players), the second asked the total time spent playing favorite video games (selective players), and the third asked the number of different video games played in a year (diverse players). Students who were medium in selective player style (spent 11-50 h) had significantly higher GPAs than students low on selective player style (spent 0-10 h). Students high on habitual playing style (7 or more hours a week) showed significantly lower levels of Conscientiousness compared to students low on habitual playing style (0-1 h a week). Students who were high on the diverse style (i.e., 7 or more games played a year) showed significantly higher Openness scores than students low on the diverse style (0-3 games a year). Finally, several notable relations were found between video game genre preference, GPA, and personality. Results are discussed in terms of the positive implications of video gameplay on academic performance. 相似文献
992.
This paper aims to propose a distributed task allocation algorithm for a team of robots that have constraints on energy resources and operate in an unknown dynamic environment. The objective of the allocation is to maximize task completion ratio while minimizing resource usage. The approach we propose is inspired by the social welfare in economics that helps extend the combined operational lifetime of the team by balancing resource consumptions among robots. This social welfare based task allocation method positions a robot team appropriately in preparedness for dynamic future events and enables to achieve the objectives of the system flexibly depending on the application context. Our simulation-based experiments show that the proposed algorithm outperforms a typical market-based approach in various scenarios. 相似文献
993.
Forced internal waves at the interface of a two-layer incompressible fluid in a two-dimensional domain with rigid horizontal boundaries are studied. The lower boundary is assumed to have a small obstruction. We derive a time-dependent forced modified KdV equation when the KdV theory fails and study the stabilities of four types of symmetric time-independent solitary-wave-like solutions numerically. 相似文献
994.
A number of studies have examined virtual worlds, which can facilitate knowledge sharing, education, and enjoyment, among others. However, no study has provided an insightful research model for evaluating virtual worlds. This study suggests that users’ identification with virtual communities and avatars plays a critical role in the construction of attractive virtual worlds. The proposed model measures the level of the user’s identification with virtual communities, through which the user builds his or her trust in other community members. In addition, the study suggests that users’ identification with avatars is an important element of their satisfaction with virtual worlds. The results indicate that users’ identification with virtual communities as well as avatars can enhance their efficacy and trust and thus facilitate their sustained use of virtual services. The results have important theoretical and practical implications. 相似文献
995.
The current study reconceptualized self-construal as a social cognitive indicator of self-observation that individuals employ for developing and maintaining social relationship with others. From the social cognitive perspective, this study investigated how consumers’ self-construal can affect consumers’ electronic word of mouth (eWOM) behavior through two cognitive factors (online community engagement self-efficacy and social outcome expectations) in the context of a social networking site. This study conducted an online experiment that directed 160 participants to visit a newly created online community. The results demonstrated that consumers’ relational view became salient when the consumers’ self-construal was primed to be interdependent rather than independent. Further, the results showed that such interdependent self-construal positively influenced consumers’ eWOM behavioral intentions through their community engagement self-efficacy and their social outcome expectations. 相似文献
996.
Social media services such as YouTube and Flickr have become online necessities for millions of users worldwide. Social media are online services that enable users to share contents, opinions, and perspectives that support communication with other users. Social media places an emphasis on the shared experience between users, which we call co-experience. However, the online characteristics of social media increase psychological distance between users, which, in turn, results in a decrease in the quality of co-experience. Hence, as the goal of this study, we theoretically modeled and empirically verified the antecedents and user experience-based consequences of psychological distance in a social media-enhanced real-time streaming video service. In order to reduce psychological distance, we introduced two system elements: inhabited space (the degree of being situated in context and in a meaningful place) and isomorph effects (the degree of preserving the structure of a user’s actions). We constructed a social media-enhanced real-time streaming video service prototype and conducted a field experiment with actual social media users. The prototype, which streamed a live baseball game, enabled users to simultaneously view the game from remote locations and to interact with each other through cheering tools. The results indicate that inhabited space and isomorph effects reduce psychological distance between users, and this, in turn, enhances co-experience. This paper ends with theoretical as well as practical implications of the study. 相似文献
997.
Artificial neural networks (ANNs) have been popularly applied for stock market prediction, since they offer superlative learning
ability. However, they often result in inconsistent and unpredictable performance in the prediction of noisy financial data
due to the problems of determining factors involved in design. Prior studies have suggested genetic algorithm (GA) to mitigate
the problems, but most of them are designed to optimize only one or two architectural factors of ANN. With this background,
the paper presents a global optimization approach of ANN to predict the stock price index. In this study, GA optimizes multiple
architectural factors and feature transformations of ANN to relieve the limitations of the conventional backpropagation algorithm
synergistically. Experiments show our proposed model outperforms conventional approaches in the prediction of the stock price
index. 相似文献
998.
Currently, embedded systems have been widely used for ubiquitous computing environments including digital setup boxes, mobile
phones, and USN (Ubiquitous Sensor Networks). The significance of security has been growing as it must be necessarily embedded
in all these systems. Up until now, many researchers have made efforts to verify the integrity of applied binaries downloaded
in embedded systems. The research of problem solving is organized into hardware methods and software-like methods. In this
research, the basic approach to solving problems from the software perspective was employed. From the software perspective,
unlike in the existing papers (Seshadri et al., Proc. the IEEE symposium on security and privacy, 2004; Seshadri et al., Proc. the symposium on operating systems principals, 2005) based on the standardized model (TTAS.KO-11.0054.
2006) publicized in Korea, there is no extra verifier and conduct for the verification function in the target system. Contrary
to the previous schemes (Jung et al. , 2008; Lee et al., LNCS, vol. 4808, pp. 346–355, 2007), verification results are stored in 1 validation check bit, instead of storing signature value for application binary files
in the i-node structure for the purpose of reducing run-time execution overhead. Consequently, the proposed scheme is more
efficient because it dramatically reduces overhead in storage space, and when it comes to computing, it performs one hash
algorithm for initial execution and thereafter compares 1 validation check bit only, instead of signature and hash algorithms
for every application binary. Furthermore, in cases where there are frequent changes in the i-node structure or file data
depending on the scheme application, the scheme can provide far more effective verification performance compared to the previous
schemes. 相似文献
999.
Sangseok Yun Bongjin Jun Daijin Kim Jaewoong Kim Sukhan Lee Mun-Taek Choi Munsang Kim Joong-Tae Park Jae-Bok Song 《Journal of Intelligent and Robotic Systems》2012,67(2):79-99
This paper describes a scheme for proactive human search for a designated person in an undiscovered indoor environment without human operation or intervention. In designing and developing human identification with prior information a new approach that is robust to illumination and distance variations in the indoor environment is proposed. In addition, a substantial exploration method with an octree structure, suitable for path planning in an office configuration, is employed. All these functionalities are integrated in a message- and component-based architecture for the efficient integration and control of the system. This approach is demonstrated by succeeding human search in the challenging robot mission of the 2009 Robot Grand Challenge Contest. 相似文献
1000.
IP traceback is an effective measure to deter internet attacks. A number of techniques have been suggested to realize IP traceback. The Fragment Marking Scheme (FMS) is one of the most promising techniques. However, it suffers a combinatorial explosion when computing the attacker?s location in the presence of multiple attack paths. The Tagged Fragment Marking Scheme (TFMS) has been suggested to suppress the combinatorial explosion by attaching a tag to each IP fragment. Tagging is effective because it allows the victim to differentiate IP fragments belonging to different routers, thereby greatly reducing the search space and finding the correct IP fragments. TFMS, however, increases the number of false positives when the number of routers on the attack path grows beyond some threshold. In this paper, we rigorously analyze the performance of TFMS to determine the correlation between the number of routers and the false positive error rate. Using a probabilistic argument, we determine the formulas for combination counts and error probabilities in terms of the number of routers. Under TFMS, our results show that we can reduce the required time to find an attacker?s location at the cost of a low error rate for a moderate number of routers. 相似文献