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151.
In this paper, we consider three different search strategies for a cut-free sequent system formalizing orthologic, and estimate the respective search spaces. Applying backward search, there are classes of formulae for which both the minimal proof length and the search space are exponential. In a combined forward and backward approach, all proofs are polynomial, but the potential search space remains exponential. Using a forward strategy, the potential search space becomes polynomial yielding a polynomial decision procedure for orthologic and the word problem for free ortholattices.  相似文献   
152.
Abstract: Ninety‐nine Japanese students received one of three offers in an ultimatum bargaining scenario: unfavorable and unequal; equal; or favorable but unequal. These offers were determined by either the other participant or by a computerized lottery. We also manipulated the arbitrariness of the role assignment procedure. Participants perceived the intentional small offer as more unfair in the interactional sense than the unintentional small offer, while they perceived the same offers as unfair in the distributive sense, regardless of intentionality. The intentional small offer was more likely to be rejected than the unintentional small offer. Participants perceived the arbitrary procedure of the role assignment as highly unfair, whereas the difference of arbitrariness in role assignment procedures had no significant impact on their reactions to the offer. Acceptance of the offer was strongly determined by interactional fairness, as well as by distributive fairness, and these types of fairness were influenced by different situational characteristics, such as intentionality, the size of the offer, and the equality of the offer.  相似文献   
153.
Pigeons were trained in a matching task with either color (group color-first) or line (group line-first) samples. After asymmetrical training in which each group was initially trained with the same sample on all trials, marked retention asymmetries were obtained. In both groups, accuracy dropped precipitously on trials involving the initially trained sample and remained high on trials involving the sample introduced second in training, suggesting that asymmetrical training encouraged a single-code/default strategy in which only the sample trained initially was coded. Pigeons next received concurrent training with the alternate set of samples mapped to the same set of comparisons as were the first set of samples (many-to-one, MTO, procedure). Retention testing revealed no marked retention asymmetries in group line-first whereas marked retention asymmetries occurred with both sets of samples in group color-first. Hence, only birds in group color-first continued to use a single-code/default strategy after MTO training.  相似文献   
154.
普遍的正义如何可能——柏拉图正义论及发微   总被引:1,自引:0,他引:1  
柏拉图试图解决正义是什么、正义如何可能和正义是何种价值这样一些根本问题 ,其提问题的方式、解决路径都是柏拉图式的。有借鉴意义的是正义植根于心灵深处的土壤以及社会供给正义的途径。实现正义是一个艰难且复杂的社会历史过程 ,推进民主进程、使正义理念扎根于民众的日常生活深处 ,相对正义的社会才会被建立起来 ,基于此种理念之上的用以保证、体现和实现正义的制度才会被设计出来。  相似文献   
155.
微创技术的发展:历史、现实和未来   总被引:5,自引:0,他引:5  
根据"看"的技术不同,微创技术可以分为两类和三种.目前,微创技术正处于以内镜、腔镜、介入X-线、介入超声以及微创化外科技术为主的技术发展阶段.展望未来,微创技术可能出现三种发展趋势:(1)现有技术的进一步完善、提高;(2)现有不同技术的相互融合;(3)微创新技术的发明.  相似文献   
156.
医院门诊计算机就医流程中的人文思考   总被引:2,自引:0,他引:2  
医院门诊就医流程是门诊服务和管理的基础,应用现代网络技术是将传统的就医模式转变为以人为本模式的重要技术手段.介绍了医院在"军字一号"上自行设计的,涵括门诊挂号排队系统、门诊预交金卡系统、门诊药房后台摆药系统、门诊检验条形码系统、门诊医学影像传输系统的"直通式"就医流程.就门诊新就医流程中医患互动、人-机-人对话和门诊病人知情权等可能出现的状况加以人文思考.  相似文献   
157.
Previous studies of computer criminals have attempted to differentiate between offenders, but have not used data from the actual attacks. Drawing on theories from investigative psychology as well as information security, the current study differentiates 2755 computer security incidents using information about Method of Operation (MO), Impact, and Source Sector from reported attacks. Multivariate statistical analyses were applied on the data‐matrix of 22 variables and showed the co‐occurrences of various aspects of computer security incidents. A radex structure emerged where the high frequency variables were positioned in the centre of the data‐plot. Based on a previously developed taxonomy of cyber intrusions, the results of the analysis showed that it was possible to draw inferences about the less informative category of Objective, from information about Attacker, Tools, Access, and Results. By applying the division‐lines indicating the Objectives of Challenge/Status, Destruction, Political Gain and Financial Gain on the SSA‐plot, it was shown how the taxonomies could be further developed by taking into account the relationships between the categories. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
158.
Two experiments investigated the derived transfer of functions through equivalence relations established using a stimulus pairing observation procedure. In Experiment 1, participants were trained on a simple discrimination (A1+/A2-) and then a stimulus pairing observation procedure was used to establish 4 stimulus pairings (A1-B1, A2-B2, B1-C1, B2-C2). Subsequently, a transfer of the simple discrimination functions through equivalence relations was observed (e.g., C1+/C2-). These procedures were modified in Experiment 2, which demonstrated that spider-fearful and non-spider-fearful participants show differing levels of a transfer of self-reported arousal functions for stimuli used in equivalence relations with video-based material depicting scenes with spiders. The results demonstrate that the stimulus pairing observation procedure provides a viable alternative to matching-to-sample, and also offer tentative support for a derived-relations model of the acquisition of anxiety responses in at least one sub-clinical population.  相似文献   
159.
This experiment tested for transitivity in pigeons' choices between variable-time (VT) and fixed-time (FT) schedules. In a discrete-trials procedure, a subject chose between two alternatives by making a single key peck. Each choice was between a "standard alternative," which was the same schedule throughout a condition, and an "adjusting alternative," in which the delay to reinforcement was systematically increased or decreased many times a session. These adjustments enabled an approximate indifference point to be identified--the value of the adjusting delay at which the subject chose each alternative about equally often. Each test of transitivity involved four conditions. In one, the standard alternative was a variable-time schedule with a 2-s reinforcer, and the adjusting alternative also delivered a 2-s reinforcer. A second condition was similar except that the adjusting alternative delivered a 5-s reinforcer. The indifference point from each of these conditions was then converted to a fixed-time schedule for subsequent comparisons in the third and fourth conditions, respectively. Each of these last two conditions compared one of the fixed-time schedules (based upon the previous conditions and including their different reinforcer durations) with an adjusting schedule that delivered the alternative reinforcer duration, to determine whether the obtained indifference points would be those predicted from the prior alternative-duration comparisons with the VT schedule. There was little evidence for intransitivity of choice: Averaged across subjects and replications, the obtained indifference points deviated from perfect transitivity by less than 8%, and these deviations were not statistically significant. These results contrast with those of Navarick and Fantino (1972), who found frequent violations of transitivity between periodic and aperiodic schedules using a concurrent-chains procedure with variable-interval schedules in the initial links.  相似文献   
160.
Rats' responses were reinforced on concurrent variable-ratio variable-ratio schedules in which responses on one lever incremented the ratio counter and responses on a second lever changed the schedule and correlated stimulus. The relative frequency of reinforcement was varied from .10 to .99. In one set of conditions, responding on the main lever incremented both ratio counters, but reinforcement required a response in the presence of the stimulus correlated with the ratio that had been completed. In a second set of conditions, responses on the main lever incremented only the ratio correlated with the stimulus that was currently present. When main-lever responses incremented both ratio counters, subjects distributed responding and time in a manner consistent with the generalized matching law. When responses on the main lever incremented only the schedule currently in effect, the rats responded almost exclusively on the schedule producing the higher frequency of reinforcement. These results extend the applicability of the generalized matching law to dependent ratio schedules.  相似文献   
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