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41.
Intrusion Detection Systems (IDSs) is a system that monitors network traffic for suspicious activity and issues alert when such activity is revealed. Moreover, the existing IDSs-based methods are based on outdated attacks that unable to identify modern attacks or malicious trends. For this reason, in this study we developed a new multi-swarm adaptive grasshopper optimization algorithm to utilize adaptation mechanism in a group of swarms based on fuzzy logic to protect against sophisticated attacks. The proposed (MSAGOA) technique has the capability of global optimization and rapid convergence that are used to attain optimal feature subsets to identify attack types on IDS datasets. In the MSAGOA technique, learning engine as Extreme learning Machine, Naive Bayes, Random Forest and Decision Tree is applied as a fitness function to select the highly discriminating features and to maximize classification performance. Afterward, select the best classifier which works as a fitness function in our approach to measure the performance in terms of accuracy, detection rate, and false alarm rate. The simulations are performed on three IDS datasets such as NSL-KDD, AWID-ATK-R, and NGIDS-DS. The experimental results demonstrated that MSAGOA method has performed better and obtained high detection rate of 99.86%, accuracy of 99.89% in NSL-KDD and high detection rate of 98.73%, accuracy of 99.67% in AWID-ATK-R and detection rate of 89.50%, accuracy of 90.23% in NGIDS-DS. In addition, the performance is compared with several other existing techniques to show the efficacy of the proposed approach. 相似文献
42.
D. Caroline Blanchard Nina K. Popova Irina Z. Plyusnina Irina L. Velichko Desiree Campbell Robert J. Blanchard Julia Nikulina Ella M. Nikulina 《Aggressive behavior》1994,20(5):387-397
Selective breeding of wild rats over many generations on the basis of low or high defensive threat and attack to human approach and contact has produced highly polarized “domesticated” and “wild-type” animals. Because the selection procedure selectively involves these two defense patterns, and these clearly differ in the two groups, it is of interest to determine if other, nonselected, defensive behaviors to threat stimuli also change. “Domesticated” and “wild-type” rats of the thirty-fifth generation were run in a fear defense test battery (F/DTB) to systematically evaluate defensive behaviors to a variety of present threat stimuli. “Domesticated” rats showed reduced avoidance and slower flight speed to an approaching experimenter, reduced jump/startle response to handelap and dorsal contact, less vocalization and boxing to vibrissae stimulation or to an anesthetized conspecific, and reduced defensiveness to an attempted pickup by the experimenter. These results indicate that selective bi-directional breeding for defensive threat and attack to human approach and contact produces group differences in a variety of defensive behaviors, and in defensiveness to stimuli other than those on which the selection was based. © 1994 Wiley-Liss, Inc. 相似文献
43.
Researchers have recently begun to evaluate video-based preference assessments; however, only two studies have evaluated the efficacy of this preference assessment modality in assessing preference for social interactions. Four individuals diagnosed with autism spectrum disorder who could not match pictures or graphic-interchange-format images (GIFs) of social interactions to in vivo interaction participated. We compared picture and GIF-based paired-stimulus preference assessments for social interaction and evaluated the preference assessment hierarchies by conducting a concurrent-operant reinforcer assessment including all social interactions. The GIF-based preference assessment produced similar hierarchies to the reinforcer assessment for all participants, whereas the picture-based preference assessments produced similar hierarchies to the reinforcer assessment for 2 of 4 subjects. Additionally, we conducted a modality preference assessment in which we evaluated participants' preference for viewing GIFs or pictures of social interactions, and found that 3 out of 4 subjects displayed a preference for GIFs. 相似文献
44.
Kate E. Fiske Robert W. Isenhower Meredith J. Bamond Stacy Lauderdale-Littin 《Journal of applied behavior analysis》2020,53(1):563-571
Token systems are widely used in clinical settings, necessitating the development of methods to evaluate the reinforcing value of these systems. In the current paper, we replicated the use of a multiple-schedule reinforcer assessment (MSA; Smaby, MacDonald, Ahearn, & Dube, 2007) to evaluate the components of a token economy system for 4 learners with autism. Token systems had reinforcing value similar to primary reinforcers for 2 of the 4 learners, but resulted in lower rates of responding than primary reinforcers for the other 2 learners. Differentiated responding across learners may warrant variation in clinical recommendations on the use of tokens. The results of this study support formal assessment of token system effectiveness, and the MSA procedure provides an efficient method by which to conduct such assessments. 相似文献
45.
Andrew B. Speer Sydney R. Siver Neil D. Christiansen 《International Journal of Selection & Assessment》2020,28(1):68-84
Despite being an effective predictor of job performance, empirically keyed biodata assessments have been criticized as black box empiricism unlikely to generalize to new contexts. This paper introduces a model that challenges this perspective, explicating how biodata content, job demands, and criterion variables collectively influence the construct validity, and generalizability of empirically scored biodata. Across two field studies, expected changes in scale correlations with external measures were found that coincided with changes in the contextual similarity between calibration and holdout contexts, the criteria used, and the content validity of biodata items. Collectively, this paper offers a framework that helps understand and optimize empirical biodata keying in practice, furthering confidence for their use in applied settings. 相似文献
46.
Christopher J. Hartwell Michael A. Campion 《International Journal of Selection & Assessment》2020,28(1):1-16
The use of social networking websites (SNWs) during employee selection is gaining popularity in organizations. Using a foundation that integrates identity and situational strength theories, we develop a conceptual framework that differentiates SNW information from information gathered through traditional selection procedures, and distinguishes between SNW types. Research questions and hypotheses are tested using a survey of 291 hiring professionals. Results indicate that SNW content is considered useful and is regularly utilized during hiring. Some SNW content is viewed positively (e.g., information supporting qualifications), while other information leads to negative perceptions (e.g., discriminatory comments). Finally, results support a differentiation between personal and professional SNW, as the kind of information sought and the effectiveness of assessing various work‐related constructs differs between these SNW categories. 相似文献
47.
视觉工作记忆中(VWM)已稳定存储的表征,依然会受内部注意选择的影响,说明内部注意选择对VWM发挥重要作用。本文首先阐述该领域主要的研究方法,然后对VWM中内部注意选择的效果和四个特性:时程、对象、容量和可持续性,以及其背后可能的理论机制和神经机制进行分析和总结。并据此从VWM的存储结构、内部注意的产生机制和处理方式等方面,为未来研究提出方向和建议。 相似文献
48.
Lee Ellis 《Aggressive behavior》1986,12(1):57-71
Within the framework of modern evolutionary theory, arguments are reviewed that the nonlegal equivalent of aggressive criminal behavior may have evolved by natural selection among mammals, particularly primates, as part of their overall approach to reproduction. If so, the commission of aggressive crimes (or their nonlegal equivalent) by humans, and even efforts to prevent fellow social group members from being victimized by aggressive crimes, may also be partially explainable in natural selection terms. The plausibility of this deduction was explored, first, by specifying the three elements that a human act must have to be regarded as an aggressive crime. Summarily, these were that (1) injury to a victim must be a likely result of the act, (2) the act must be intended, and (3) the act must elicit negative responses from those witnessing it. The primate behavior literature was examined for evidence that some behavior of nonhumans met all three conditions. Affirmative results were obtained. Therefore, while further research is in order, human aggressive criminal behavior, as well as human efforts to control it, seem to have close parallels in other primates. This would be consistent with the notion that aggressive criminal behavior (along with its condemnation by fellow group members) is part of a social system produced and sustained by natural selection. 相似文献
49.
Lindauer SE Zarcone JR Richman DM Schroeder SR 《Journal of applied behavior analysis》2002,35(3):299-303
Functional analysis results indicated that maladaptive behaviors displayed by a 25-year-old man with profound mental retardation were maintained by attention from caregivers and possibly, to a lesser degree, by access to tangible items. A concurrent-schedules procedure was then used to study the relative reinforcing value for maladaptive behavior of attention versus tangible items. Results of the concurrent-schedules assessment and subsequent functional communication training indicated that preference for attention versus access to a tangible object varied. 相似文献
50.
Griffin ZM 《Brain and language》2002,80(3):465-487
Three experiments examined the contribution of phonological availability in selecting words as predicted by interactive activation models of word production. Homophonous words such as week and weak permitted a word's phonological form to be activated on priming trials without selection of its meaning or lemma. Recent production of a homophone failed to significantly increase production of its twin as a sentence completion. However, speakers were significantly more likely to complete a sentence with a recently read or generated unambiguous word. This increase in response probability was unaffected by word frequency. The results constrain the degree to which experience and phonological availability may affect word selection in spoken language production. 相似文献