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181.
Theory Reduction in the Social Sciences. The example of balance theories. A central topic both in philosophy of science as well as in the empirical sciences is the reconstruction of the relations between theories. In the past comparisons of theories by means of traditional linguistic methods have proved to be extremely difficult and complicated. In this article the reconstruction of intertheoretical relations based on model-theoretical terms is propagated, as formulated within the structuralist view of theories. The efficiency of a model theoretical based comparison of theories is demonstrated by two theory elements from the social science research program of balance theories: The basic element by Heider and the transitivity theory by Holland and Leinhardt. First of all both theory elements are introduced informally and reconstructed in the structuralist format. On the basis of these reconstructions can be shown, that the Heider theory can be formally reduced to the Holland-Leinhardt theory and that the theory younger in history means an improvement. However, an integration of all balance theoretical elements into a theory net is not possible. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
182.
Models of choice in concurrent-chains schedules are derived from melioration, generalized matching, and optimization. The resulting models are compared with those based on Fantino's (1969, 1981) delay-reduction hypothesis. It is found that all models involve the delay reduction factors (T - t2L) and (T - t2R), where T is the expected time to primary reinforcement and t2L, t2R are the durations of the terminal links. In particular, in the case of equal initial links, the model derived from melioration coincides with Fantino's original model for full (reliable) reinforcement and with the model proposed by Spetch and Dunn (1987) for percentage (unreliable) reinforcement. In the general case of unequal initial links, the model derived from melioration differs from the revised model advanced by Squires and Fantino (1971) only in the factors affecting the delay-reduction terms (T - t2L) and (T - t2R). The models of choice obtained by minimizing the expected time to reinforcement depend on the type of feedback functions used. In particular, if power feedback functions are used, the optimization model coincides with that obtained from melioration.  相似文献   
183.
Responding on concurrent-chains schedules in open and closed economies.   总被引:1,自引:1,他引:0  
Pigeons' key pecks were reinforced according to concurrent-chains schedules of reinforcement. The programmed average time from the onset of the initial links to a terminal link entry was held constant across conditions while the value of variable-interval schedules in the terminal links was varied. Performance was assessed under two economic conditions: (a) an open economy in which session duration was limited to 1 hr and subjects were maintained at 80% of their free-feeding body weights with postsession food when necessary; and (b) a closed economy in which sessions were 23.5 hr long and no deprivation regimen was in effect. In all cases, the relative rate of responding in the initial links matched the reduction in overall delay to primary reinforcement correlated with entry into one terminal link relative to the reduction in delay correlated with entry into the other terminal link. Although the sum of responses made in the initial links and terminal links was found to increase, then decrease, as the rate of food presentation decreased in the closed economy, there was no consistent effect of overall rate of food presentation on total responding in the open economy. The choice data suggest that relative delay reduction predicts choice accurately, regardless of economic context.  相似文献   
184.
In order to tackle food waste at the prevention stage of the waste hierarchy, an understanding of behaviour that leads to wastage is required. This article examines consumer food waste behaviour in a university setting and the implications for encouraging sharing as a means of mitigating food waste. The embodied and embedded nature of consumption and wasteful behaviours are contended, giving explanation to the transition of food into waste. By undertaking a mixed‐method study and a social media‐based intervention, behaviour that causes food to be wasted within a campus environment is discussed, furthering the current domestic focus of research. The paper argues that consumer food waste behaviour can be better understood by focusing on the practices, routines and habits of consumers given the hidden nature of the food waste issue. A number of barriers are also presented regarding the sharing of food as a means of food waste prevention. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
185.
There is now considerable evidence that human sentence processing is expectation based: As people read a sentence, they use their statistical experience with their language to generate predictions about upcoming syntactic structure. This study examines how sentence processing is affected by readers' uncertainty about those expectations. In a self‐paced reading study, we use lexical subcategorization distributions to factorially manipulate both the strength of expectations and the uncertainty about them. We compare two types of uncertainty: uncertainty about the verb's complement, reflecting the next prediction step; and uncertainty about the full sentence, reflecting an unbounded number of prediction steps. We find that uncertainty about the full structure, but not about the next step, was a significant predictor of processing difficulty: Greater reduction in uncertainty was correlated with increased reading times (RTs). We additionally replicated previously observed effects of expectation violation (surprisal), orthogonal to the effect of uncertainty. This suggests that both surprisal and uncertainty affect human RTs. We discuss the consequences for theories of sentence comprehension.  相似文献   
186.
College students received points exchangeable for money (reinforcement) on a variable-time 60-second schedule that alternated randomly with an extinction component. Subjects were informed that responding would not influence either the rate or distribution of reinforcement. Instead, presses on either of two levers (“observing responses”) produced stimuli. In each of four experiments, stimuli positively correlated with reinforcement and/or stimuli uncorrelated with reinforcement were each chosen over stimuli correlated with extinction. These results are consistent with prior results from pigeons in supporting the conditioned-reinforcement hypothesis of observing and in not supporting the uncertainty-reduction hypothesis.  相似文献   
187.
The effects of two different procedures for reducing elevator energy use were assessed using a multiple-baseline design. In the first procedure, feedback about the amount of energy consumed by the elevators each week was posted on each elevator door. Later, signs advocating the use of stairs to save energy and improve health were posted next to the feedback signs. In the second procedure, the time required to travel between floors was increased by adding a delay to the elevator door closing mechanisms. Results indicated that neither feedback alone nor feedback plus educational signs reduced the amount of energy consumed by the elevators. However, use of the door delay reduced consumption by one-third in all elevators.A second experiment replicated the effect of the door delay on energy consumption and, in addition, demonstrated that the door delay also produced a reduction in the number of persons using the elevator. The second experiment also showed that, following an initial period during which a full delay was in effect, a gradual reduction of the delay interval resulted in continued energy conservation. Reduced convenience as a general strategy for energy conservation is discussed.  相似文献   
188.
Continued public support for the design, implementation, and dissemination of preventive interventions depends on achievement of four major criteria: (a) Reductions in the incidence or prevalence rates of diagnosable emotional and behavioral disorders, (b) reductions in the need for mental health services through effective primary and secondary interventions, (c) enhancement of the effectiveness of obtained services as screening and early detection efforts are implemented, and (d) reductions in the nation's health care costs associated with emotional and behavioral dysfunctions. Strategies including risk reduction, risk avoidance, health promotion, empowerment, and resource development are preventive insofar as they contribute to achievement of the aforementioned outcomes.  相似文献   
189.
Rats were trained on a free-operant procedure in which shock duration was controlled by responses within a limited range of interresponse times. Shocks of 1.6-mA intensity occurred randomly with average density of 10 shocks per minute. As long as interresponse times were 15 seconds or less, any shocks received were at the briefer of two durations (.3 second). Whenever interresponse times exceeded 15 seconds, any shocks received were at the longer duration (1.0 second). For six of eight animals, avoidance responding developed quickly and reached levels of better than 90%. Four yoked animals stopped responding within the first few sessions. Shock duration reduction without change in shock probability or intensity was sufficient for the acquisition and maintenance of avoidance responding.  相似文献   
190.
Social networking sites (SNS) are a rich source of extractive information about job applicants. Human resources (HR) professionals now use SNS to gather additional information about job applicants; consequently, job applicants begin interviewing even before the actual interview. The authors examine SNS in the context of hiring decisions, using uncertainty reduction theory as a framework of analysis to explain how individuals obtain and process information about interpersonal relationships to reduce uncertainty before a face‐to‐face meeting. The authors recommend mandatory training for HR professionals, recruiters, and applicants in the strategic use and placement of SNS profiles in the public domain.  相似文献   
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