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排序方式: 共有700条查询结果,搜索用时 437 毫秒
101.
针对电子调查存在的不少安全问题,如信息欺骗、隐私安全等,构建了一个基于非交互零知识证明(NIZK,non-interactive zero knowledge proofs)的匿名电子调查系统,系统具有自组织、非交互、防重放、更安全等特点。系统采用NIZK协议和Boneh-Boyen签名方案对用户的身份进行非交互式的验证,保证了系统的真实性;系统还采用Pedersen承诺方案和伪随机函数对用户的身份和相关信息进行隐藏,保证了系统的匿名性。安全性分析表明,系统具有抵抗恶意用户并发攻击和匿名性等安全特性。最后,对系统的功能进行了仿真并验证,结果表明,系统能够正确完成各项功能,并有效地保证系统的匿名性与真实性。 相似文献
102.
103.
Juan Chen Xiaojiang Du Binxing Fang 《Wireless Communications and Mobile Computing》2012,12(14):1302-1312
Anonymous communication is very important for many wireless sensor networks, because it can be used to hide the identity of important nodes, such as the base station and a source node. In sensor networks, anonymous communication includes several important aspects, such as source anonymity, communication relationship anonymity, and base station anonymity. Existing sensor network anonymous schemes either cannot achieve all the anonymities or have large computation, storage, and communication overheads. In this paper, we propose an efficient anonymous communication protocol for sensor networks that can achieve all the anonymities while having small overheads on computation, storage, and communication. We compare our anonymous communication protocol with several existing schemes, and the results show that our protocol provides strong anonymity protection and has low overheads. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
104.
Eighty pomelo samples and 80 soil samples were examined using a multielement component test to predict the geographical origins of pomelos produced in 4 regions (Sichuan, Chongqing, Fujian, and Guangxi Provinces) of China. The concentrations of 8 elements were determined by atomic absorption spectrometry. Ca, K, and Na were the most abundant elements. Principal component analysis (PCA) and linear discriminant analysis (LDA) were applied to reduce the dimensionality of the multielement data from 8 to 2 while retaining the highest possible variance. Using PCA and LDA, 69.66% and 91.30%, respectively, of the pomelo origins were classified correctly using multielement variables, along with 67.06% and 83.40% for soil multielement analysis. Results indicated that the LDA method was more effective for geographical origin classification than PCA. The results of the multielement component test demonstrated its capability to screen pomelo origins rapidly. 相似文献
105.
Niu L Mantri N Li CG Xue C Wohlmuth H Pang EC 《Journal of the science of food and agriculture》2011,91(7):1310-1315
BACKGROUND: Food adulteration remains a major global concern. DNA fingerprinting has several advantages over chemical and morphological identification techniques. DNA microarray‐based fingerprinting techniques have not been used previously to detect adulteration involving dried commercial samples of closely related species. Here we report amplification of low‐level DNA obtained from dried commercial ginseng samples using the Qiagen? REPLI‐g® Kit. Further, we used a subtracted diversity array (SDA) to fingerprint the two ginseng species, Panax ginseng and Panax quinquefolius, that are frequently mixed for adulteration. RESULTS: The two ginseng species were successfully discriminated using SDA. Further, SDA was sensitive enough to detect a deliberate adulteration of 10% P. quinquefolius in P. ginseng. Thirty‐nine species‐specific features including 30 P. ginseng‐specific and nine P. quinquefolius‐specific were obtained. This resulted in a feature polymorphism rate of 10.5% from the 376 features used for fingerprinting the two ginseng species. The functional characterization of 14 Panax species‐specific features by sequencing revealed one putative ATP synthase, six putative uncharacterized proteins, and two retroelements to be different in these two species. CONCLUSION: SDA can be employed to detect adulterations in a broad range of plant samples. Copyright © 2011 Society of Chemical Industry 相似文献
106.
Anonymous channel tickets have been proposed as a way to provide user anonymity and to reduce the overhead of re‐authentication for authentication in wireless environments. Chen et al. proposed a secure and efficient protocol, based on a protocol proposed by Yang et al., which is resistant to guessing attacks on networks from which users’ secret keys are easy to obtain. However, their scheme is time‐consuming in the phases of ticket issuing and authentication. Furthermore, a malicious attacker can utilize the expired time, Texp, to launch a denial of authentication (DoA) attack, which is a type of denial of service attack. Because Texp is exposed to any user, it would be easy to launch a DoA attack that could make the scheme impractical. To resist against DoAs that the scheme of Chen et al. might suffer, we propose an improved scheme based on elliptic curve cryptography in this paper. Our scheme not only reduces time cost but also enhances security. The basis of the proposed scheme is the elliptic curve discrete logarithm problem. The operations of points of an elliptic curve are faster and use fewer bits to achieve the same level of security. Therefore, our scheme is more suitable for mobile devices, which have limited computing power and storage. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
107.
Edoardo Capuano Teresa Oliviero Martinus A.J.S van Boekel 《Critical reviews in food science and nutrition》2018,58(16):2814-2828
ABSTRACTThe same chemical reaction may be different in terms of its position of the equilibrium (i.e., thermodynamics) and its kinetics when studied in different foods. The diversity in the chemical composition of food and in its structural organization at macro-, meso-, and microscopic levels, that is, the food matrix, is responsible for this difference. In this viewpoint paper, the multiple, and interconnected ways the food matrix can affect chemical reactivity are summarized. Moreover, mechanistic and empirical approaches to explain and predict the effect of food matrix on chemical reactivity are described. Mechanistic models aim to quantify the effect of food matrix based on a detailed understanding of the chemical and physical phenomena occurring in food. Their applicability is limited at the moment to very simple food systems. Empirical modeling based on machine learning combined with data-mining techniques may represent an alternative, useful option to predict the effect of the food matrix on chemical reactivity and to identify chemical and physical properties to be further tested. In such a way the mechanistic understanding of the effect of the food matrix on chemical reactions can be improved. 相似文献
108.
109.
本文在对无线mesh网络深入研究的基础上,针对mesh网络环境下的隐私保护需求,提出在无线mesh网络下基于网络编码的匿名通信机制。该方案将多径路由技术与网络编码技术相结合,应用跨层协作机制降低了无线环境下的数据包重传,提高了网络的传输效率,保证了网络传输的可靠性。 相似文献
110.
J. D. Nunes-Miranda G. Igrejas E. Araujo Miguel Reboiro-Jato J. L. Capelo 《Critical reviews in food science and nutrition》2013,53(7):751-759
In this work we have critically revised and updated the literature dealing with wine quality control based on protein or peptide mass spectrometry-based fingerprinting. A number of pitfalls in the experimental design of most work dealing with this subject are highlighted along with recommendations on how to circumvent them. As a general trend, the conclusions reported to date in the literature of the topic are inconclusive mainly due to the (i) low number of representative samples, (ii) lack of basic analytical concepts, and (iii) lack of adequate statistical and software tools. In addition, we have critically revised the sample treatments commonly used to separate proteins from wines, emphasizing that the majority of literature is devoted to white wines, probably because of difficulties in isolating the protein content in red wines. 相似文献