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Diana Hurdowar-Castro Ioannis Tsanis Ilmar Simanovskis 《Journal of Great Lakes research》2007,33(1):232-252
A 3D transport model is used to perform a comparative analysis of several potential drinking water intakes located along the northwest shore of Lake Ontario between Toronto and Oshawa. The model is specifically used to assess each intake under both long- and short-term transport of a potential pollutant release from the Pickering Nuclear Generating Station and potential and actual pollutant releases from local land sources respectively. A model based on a 500 m grid resolution is calibrated using data collected in the aftermath of the 1992 tritium spill at the Pickering Nuclear Generation Station and subsequently used to simulate long-term transport. A model based on a 100 m grid resolution is verified using drogue studies and used to simulate short-term transport events. Both models are used to assess pollutant levels at each of nine potential intake locations under different wind scenarios and pollutant releases. Field data for the study included water quality and flow measurements from local sewers and rivers, and estimates of pollutant levels from the local waste water treatment plants. This paper describes the model setup for both the long-term and short-term transport models, calibration using field data, long-term transport modeling, short-term transport modeling, and the comprehensive analysis approach used to evaluate the nine potential intake locations proposed. Results indicated that four intakes in particular outperformed other intake locations by maintaining bottom pollutant levels within governmental standards and warning times that exceeded 20 hours. 相似文献
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The authors examined whether participants can shift their criterion for recognition decisions in response to the probability that an item was previously studied. Participants in 3 experiments were given recognition tests in which the probability that an item was studied was correlated with its location during the test. Results from all 3 experiments indicated that participants' response criteria were sensitive to the probability that an item was previously studied and that shifts in criterion were robust. In addition, awareness of the bases for criterion shifts and feedback on performance were key factors contributing to the observed shifts in decision criteria. These data suggest that decision processes can operate in a dynamic fashion, shifting from item to item. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Participants' usage of informational variables in learning visual relative-mass discrimination in collisions was tracked by means of PROBIT correlations. Four groups received feedback that was true or accorded with either of three nonspecificational cue variables. A majority in each group adopted the feedback, but several participants defied the false feedback. Unlike in previous research, the fit to data of the relative-mass invariant could not be bettered by post hoc linear combinations of the cues. Discriminability was lower in the use of the invariant. Analytic complexity was rejected as an explanation for discriminability differences. A "smart mechanism" for pickup of the relative-mass invariant was developed as an extension of G. Johansson's (1950/1994) vector model. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Necessary and sufficient conditions for the existence of a static state feedback that achieves noninteraction and internal
stability are obtained. This is accomplished by first characterizing the set of all controllability subspaces (distributions)
that can arise as solutions to the noninteracting control problem. This characterization is then used to identify a fixed
internal dynamics that is common to every noninteractive closed loop. The stability properties of this dynamics is shown to
be the key factor in the problem of achieving noninteracting control with internal stability. 相似文献
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本文阐述阻尼式限流器参数设计选择和产品系列规划的依据原则,并结合实例说明实施步骤与方法,以有助于限流器的正确设计与选用。 相似文献
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中频变频器UFV故障探析 总被引:2,自引:1,他引:1
本文对中频变频器的UFV故障进行了系统试验和原因分析,并对UFV故障的关键因素进行了详细探析。 相似文献
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