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991.
992.
The perception of duration is crucial when we make choices between immediate and delayed rewards. Immediate rewards are valued more than the same rewards if they are delayed. Preferences for earlier rewards become even stronger when the reward can be received within a subjectively proximate time frame. A “rational” decision to wait for a delayed reward may be overruled by an “impulsive” choice when the option for the closer reward falls within this proximate time range. Based on findings on circadian and circannual physiological rhythms, we suggest that there are 2 time units that are both biologically and culturally determined and have an impact on human experience and behavior: the day and the year. We highlight results of a neuroimaging study showing that rewards with delays up to 1 year are discounted differently than reward delays longer than 1 year. This duration-dependent discounting is associated with specific brain activation in the striatum. We present various conceptualizations of subjective time incorporated in parametric models of intertemporal decisions that may lead to a better understanding of human choice behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
This article presents an agent-based microsimulation capable of forecasting the effects of policy levers that influence individual choices of new passenger cars. The fundamental decision-making units are households distinguished by sociodemographic characteristics and car ownership. A two-stage model of individual decision processes is employed. In the first stage, individual choice sets are constructed using simple, non-compensatory rules that are based on previously owned cars. Second, decision makers evaluate alternatives in their individual choice set using a multi-attributive weighting rule. The attribute weights are based on a multinomial logit model for cross-country policy analysis in European countries. Additionally, prospect theory and the notion of mental accounting are used to model the perception of monetary values. The microsimulation forecasts actual market observations with high accuracy, both on the level of aggregate market characteristics as well as on a highly resolved level of distributions of market shares. The presented approach is useful for the assessment of policies that influence individual purchase decisions of new passenger cars; it allows accounting for a highly resolved car fleet and differentiated consumer segments. As a result, the complexity of incentive schemes can be represented and detailed structural changes can be investigated. 相似文献
994.
There is growing concern in the United States about avoidable, unjust differences in health associated with sociodemographic characteristics, such as socioeconomic status and race/ethnicity. This concern has sparked research to identify how disparities develop and how they can be reduced. Studies showing that disparities occur at all levels of socioeconomic status, not simply at the very bottom, suggest that psychosocial factors play an important role. The author discusses both content and process issues in psychological research on disparities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
996.
A. G. Lanin 《Strength of Materials》2009,41(1):64-67
Fatigue behavior of brittle materials under compression is considered. The findings should be taken into account in the failure
probability assessment of components made of materials with limited plasticity, which are used in various stress states.
__________
Translated from Problemy Prochnosti, No. 1, pp. 83–87, January–February, 2009. 相似文献
997.
P. Papadopoulou N. Georgoulas L. Georgopoulos A. Thanailakis 《Electrical Engineering (Archiv fur Elektrotechnik)》2001,83(4):203-211
Contents This paper presents an analytical model for the dc electrical behavior of bulk barrier diodes (BBD's). The proposed model
extends previously published models, and includes analytical expressions for all significant quantities of the device dc performance,
i.e. barrier height, current density and ideality factor, with respect to the technological parameters and the applied voltage
in both bias conditions. The analytical results have been compared with those obtained using the 2-D device simulator S-PISCES,
which takes into account the drift–diffusion theory, as well as a concentration and field dependent mobility, the Shockley–Read–Hall
and Auger carrier recombination, and the band gab narrowing. Good agreement was obtained between theory and simulation. The
device simulation played a very important role in best understanding BBD's behavior, because it could easily take into account
parameters strongly affecting the behavior of BBD's, e.g. the free carrier presence in depletion layers, which was very difficult
for the analytical model to include.
Received: 15 January 2001 相似文献
998.
Crowd evacuation of a building has been studied over the last decades. In this paper, seven methodological approaches for crowd evacuation have been identified. These approaches include cellular automata models, lattice gas models, social force models, fluid-dynamic models, agent-based models, game theoretic models, and approaches based on experiments with animals. According to available literatures, we discuss the advantages and disadvantages of these approaches, and conclude that a variety of different kinds of approaches should be combined to study crowd evacuation. Psychological and physiological elements affecting individual and collective behaviors should be also incorporated into the evacuation models. 相似文献
999.
In the late 1980s, J. W. Fantuzzo and colleagues conducted a review of the self-management literature in order to better define the characteristics of this class of interventions. Results indicated that many interventions were minimally student-directed despite the title “self-managed” and that student-managed interventions demonstrated incremental effects above teacher-managed interventions. In the current study, updated information was compiled with regard to how self-management interventions have been described, including the degree to which self-management interventions continue to rely on external (i.e., teacher) contingencies. Review of the literature identified 16 different characterizations of self-management interventions, each of which varied widely in terms of the number of intervention components included as well as the degree to which students were involved in implementation. Although self-observation and recording of a predefined behavior appear to be the cornerstones of self-management interventions, meaningful differences were noted, including whether reinforcement was involved and whether changes in performance were tracked over time. Furthermore, although self-management interventions appear to have undergone a small shift toward increased reliance on internal (i.e., student-managed) contingencies, adults continue to play a large role in the implementation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
During the past decade, 3 major developments in psychotherapy have been converging: the establishment of evidence-based practices in psychology (EBPP); enormous growth in cognitive–behavior therapy and research (CBT); and increasing recognition of the impact of multicultural influences, as highlighted in the field of multicultural therapy (MCT). Cognitive–behavioral research has produced many empirically supported treatments used in the establishment of the scientific research base of EBPP, and MCT research has provided a wealth of qualitative information that balances this scientific emphasis with recognition of the importance of culturally competent clinical judgment, expertise, and experience. This article describes the advantages and potential limitations involved in the integration of CBT and multicultural considerations, with limitations reframed as opportunities to improve the relevance and effectiveness of psychotherapy. Ten suggestions are provided for integrating multicultural considerations into the clinical practice of cognitive–behavior therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献