首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   25729篇
  免费   847篇
  国内免费   12篇
  26588篇
  2019年   245篇
  2018年   297篇
  2017年   336篇
  2016年   381篇
  2015年   298篇
  2014年   327篇
  2013年   1833篇
  2012年   629篇
  2011年   643篇
  2010年   406篇
  2009年   421篇
  2008年   600篇
  2007年   542篇
  2006年   481篇
  2005年   477篇
  2004年   443篇
  2003年   448篇
  2002年   465篇
  2001年   685篇
  2000年   674篇
  1999年   469篇
  1998年   244篇
  1992年   467篇
  1991年   452篇
  1990年   457篇
  1989年   458篇
  1988年   408篇
  1987年   420篇
  1986年   445篇
  1985年   481篇
  1984年   410篇
  1983年   376篇
  1982年   271篇
  1981年   314篇
  1980年   243篇
  1979年   439篇
  1978年   317篇
  1977年   286篇
  1976年   274篇
  1975年   409篇
  1974年   459篇
  1973年   484篇
  1972年   410篇
  1971年   403篇
  1970年   378篇
  1969年   401篇
  1968年   493篇
  1967年   476篇
  1966年   453篇
  1958年   252篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
Binary programming models are presented to generate parallel tests from an itembank. The parallel tests are created to match item for item an existing seed test and match user supplied taxonomic specifications. The taxonomic specifications may be either obtained from the seed test or from some other user requirement. An algorithm is presented along with computational results to indicate the overall efficiency of the process. Empirical findings based on an itembank for the Arithmetic Reasoning section of the Armed Services Vocational Aptitude Battery are given.The Office of Naval Research, Program in Cognitive Science, N00014-87-C-0696 partially supported the work of Douglas H. Jones. The Rutgers Research Resource Committee of the Graduate School of Management partially supported the work of Douglas H. Jones and Ing-Long Wu. A Thomas and Betts research fellowship partially supported the work of Ing-Long Wu. The Human Resources Laboratory, United States Air Force, partially supported the work of Ronald Armstrong. The authors benefited from conversations with Dr. Wayne Shore, Operational Technologies, San Antonio, Texas. The order of authors' names is alphabetical and denotes equal authorship.  相似文献   
102.
In recent psychophysiological conceptualizations of the orienting response (OR) within the framework of information processing, the OR is increasingly considered a "call for processing resources", something which is especially inferred from variations in the event-related skin conductance response (SCR). The present study, therefore, was concerned with certain implications arising from this framework or perspective, particularly in regard to the question of whether stimuli eliciting skin conductance responses obligatorily receive/evoke processing priority or not. In order to examine whether these electrodermal responses denote a capturing of attention or merely a call for processing resources, short (1 s) pure sine tones of 65 dB with sudden onset (commonly used as orienting stimuli) were inserted in a reaction time paradigm with an additional memory load. This demand was primarily given because memory processes play a key role in theories of orienting and habituation. The task was run under two different conditions of complexity, factorially combined with a novelty variation of the added auditory stimuli. The results revealed a substantial deterioration of task performance subsequent to the occurrence of the tones, which, however, was dependent on task complexity and on novelty of the tones. The task impairment is particularly remarkable as subjects were asked to avoid distractions by paying attention to the task and as the tones were introduced as subsidiary and task-irrelevant. Together with the missing effects of task complexity on phasic and tonic electrodermal activity, results suggest that information-processing conceptualizations of the OR can only be a meaningful heuristic contribution to theoretical developments about human orienting and its habituation if the setting of processing priority, its conditions, as well as its implications are adequately taken into account. In addition, it seems to be promising to consider the strength of the SCR as an index of urgency of elaborate, attention-demanding processing and not as a peripheral physiological manifestation of the OR, or, respectively, of a call for unspecific processing resources. Such a view would also do justice to the aspect of prioritization. The sufficient conditions for an OR's occurrence could, in this context, be equated with, among others, some of those which activate a mechanism subserving selective attention and, as a possible result, which lead to further and more elaborate processing of potentially important information.  相似文献   
103.
30 subjects participated in a discrimination experiment learning face-letter associations under four rotation conditions (45 degrees, 90 degrees, 135 degrees, 180 degrees). Under each condition two thirds of the faces were presented twice, upright and rotated away from the vertical; the remaining faces were presented once, upright or rotated. Learning is described by a joint Markov model: For faces that are presented twice it assumes a separate association and encoding process (two-stage-model), for faces that are presented once it assumes an association process (all-or-none-model). The Markov model fits the data for all four rotation conditions. The angle of rotation does not affect learning for faces that are presented once. For faces that are presented twice it influences both the association and the encoding process. For the angles employed, the effect of rotation can be approximated linearly. The results suggest that the encoding of a rotated face differs increasingly from an upright face as a function of these angles of rotation. This confirms analogous conclusions from mental rotation experiments.  相似文献   
104.
Influence of animation on dynamical judgments.   总被引:3,自引:0,他引:3  
The motions of objects in the environment reflect underlying dynamical constraints and regularities. The conditions under which people are sensitive to natural dynamics are considered. In particular, the article considers what determines whether observers can distinguish canonical and anomalous dynamics when viewing ongoing events. The extent to which such perceptual appreciations are integrated with and influence common-sense reasoning about mechanical events is examined. It is concluded that animation evokes accurate dynamical intuitions when there is only 1 dimension of information that is of dynamical relevance. This advantage is lost when the observed motion reflects higher dimension dynamics or when the kinematic information is removed or degraded.  相似文献   
105.
People find their way through cluttered environments with ease and without injury. How do they do it? Two approaches to wayfinding are considered: Differential motion parallax (DMP) is a retinal motion invariant of near and far objects moving against fixation; the information in optical flow (IOF) is a radial pattern of vectors, relying on decomposition of retinal flow. Evidence is presented that DMP guides wayfinding during natural gait, accounting for errors as well as correct responses. Evidence against IOF is also presented, and a space-time aliasing artifact that can contaminate IOF displays is explored. Finally, DMP and IOF are separated, showing they can yield different results in different environments. Thus, it is concluded that (a) DMP and IOF are different, (b) DMP and not IOF is used for wayfinding, (c) moving observers do not usually decompose retinal flow, and (d) optical flow may be a mathematical fiction with no psychological reality.  相似文献   
106.
Reminder treatments have been shown to facilitate the retrieval of a variety of conditioned responses. Whether or not similar results would occur with an experimental paradigm which involves primarily memory for a stimulus, i.e., where no particular response is specified, is unclear. Accordingly, using Sprague-Dawley rats, we employed a latent inhibition paradigm with a long (10 days) retention interval between sucrose (CS) preexposure and sucrose-illness pairing (training). The results demonstrated a loss of latent inhibition following the 10-day retention interval suggesting "forgetting" of the CS preexposure. However, placing a single reminder exposure to the CS within the preexposure-to-training interval reinstated the preexposure effect. Controls indicated that in the absence of the initial preexposure the reminder per se did not produce latent inhibition. Thus, a reminder can reinstate a stimulus attribute (flavor representation) and explicit conditioned responses.  相似文献   
107.
Ss tend to remember close-up photographs as having had extended boundaries (Intraub & Richardson, 1989). Three alternate explanations were tested: object completion, distortion toward a perceptual schema, and normalization toward a prototypic view. In three experiments, 55-130 undergraduates viewed 16 close-up, prototypic, or wide-angle views of objects for 15 s each. Immediately or 48 hr later, they rated test pictures on a 5-point scale as "same", "closer up", or "father away." Results ruled out object completion because boundary extension occurred when the picture contained no incomplete objects. Immediate tests supported the perceptual schema hypothesis because all unidirectional distortions involved boundary extension. Delayed tests were more suggestive of a memory schema effect because wide-angle pictures yielded boundary restriction. A two-component model of picture processing is proposed.  相似文献   
108.
This study explored patterns emerging in videotaped sessions of group psychotherapy with seven outpatients of a large mental health facility. The 22 sessions spanned the 12th to 27th months of the group's existence. Group members had long histories (25–50 years) of symptoms characteristic of schizophrenia. Each session was rated on the Group Environment Scale. One session from a group in its earlier stages was also rated on the same instrument to give some indication of baseline patterns. Analyses of changes across the 15 months were not statistically significant. However, some GES subscales, including Cohesion, Independence, and Self-Discovery, showed relatively high mean levels across the 15-month period. These elevations are discussed as suggesting the codevelopment of orientations that have sometimes been viewed as incompatible and unattainable for schizophrenics. Interpreted clinically, the GES patterns help to elaborate recent findings about the relatively good success of long-term group therapy with such populations. The study, although merely suggestive, illustrates the potential for gleaning solid and clinically useful data from group psychotherapy research.The authors would like to thank Drs. Jill Rierdan, Nina Fieldsteel, Joseph Christy, and an anonymous reviewer for their suggestions, Kendra Bryant for serving as the reliability rater, and Janet Eltinge for her skilled videotaping.  相似文献   
109.
The authors used a correlated motion paradigm to investigate the effects of aging and gender on motion sensitivity. In 2 experiments with a total of 50 elderly and 50 young subjects, motion thresholds were significantly higher for elderly women. The correlated motion signal, which was embedded in random motion, may have been coherent to subjects in much the same way a form is in Witkin's Embedded Figures Test (EFT). In Experiment 2, EFT scores were obtained. A significant positive relationship between motion thresholds and EFT performance was found within each age group. Although gender-related perceptual style differences may contribute to motion perception effects, the authors argue that a common neural factor contributes to performance on both the EFT and the correlated motion task.  相似文献   
110.
Gerontologists have long been concerned with the impact of individual-difference factors on memory. This study used a large sample (N = 2,495) of adult volunteers aged 18 to 90 years to determine if a set of individual-difference variables--vocabulary, education, depression, gender, marital status, and employment status--mediates the effects of aging on a wide range of laboratory-analogue tests of everyday memory. The data indicated that age was consistently the most significant predictor of memory performance, followed by vocabulary and gender. Vocabulary totally mediated age effects on a prose memory measure, and partial mediation of aging effects--primarily by vocabulary and gender--was observed on 5 other memory tests. These data suggest that when health samples of volunteers serve as research subjects, these individual differences can affect some memory test scores, but age remains the best overall predictor of memory performance.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号