514 research outputs found

    A Novel Method for Calculating the Radiated Disturbance from Pantograph Arcing in High-speed Railway

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    Pantograph arcing is a key electromagnetic disturbance source to affect train control system in high-speed railway. Since the characteristics of pantograph arcing is related to train speed, it is necessary to investigate effective numerical modeling and measurement method. However, due to the uncontrollable train speed during on-site measurement, it is difficult to study the radiated disturbance from arcing in the corresponding speed and repeat the same measurement. Therefore, a method combined numerical modeling and reverberation chamber measurements for calculating the radiated disturbance from pantograph arcing in a high-speed railway is proposed. Numerical models of train and sensitive equipment are built to calculate the coupling coefficient in CONCEPT II. And a new measurement procedure in reverberation chamber using pulse signal as the reference source is proposed based on a speed-controllable laboratory replica to measure the total radiated power of pantograph arcing. Then the radiated disturbance from pantograph arcing to the sensitive equipment is achieved with the coupling coefficient and the total radiated power of arcing. The method is verified laboratory experiments. This method can solve the uncontrollable train speed problem during on-site measurement and improve the repeatability of measurement

    Psychological and educational testing and decision making:The lack of knowledge dissemination in textbooks and test guidelines

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    When it comes to decision-making based on psychological and educational assessments, there is compelling evidence that statistical judgment is superior to holistic judgment. Yet, implementing this finding in practice has proven to be difficult for both academic and professional psychologists. Knowledge transfer from research findings to practitioners and other stakeholders in psychological assessment is a necessary condition to close this gap. To obtain insight into how academic specialists in psychological testing disseminate knowledge about research findings in this area, we investigated how textbooks on testing and guidelines on test use report on, or do not to report on, decision-making in psychological and educational assessment. Second, we discuss some commonly encountered misunderstandings, and third we argue for a broader and more in-depth dissemination of research findings on this topic in textbooks and test standards; to this end we provide some suggestions

    Implementing evidence-based assessment and selection in organizations:A review and an agenda for future research

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    In personnel- and educational selection, a substantial gap exists between research and practice, since evidence-based assessment instruments and decision-making procedures are underutilized. We provide an overview of studies that investigated interventions to encourage the use of evidence-based assessment methods, or factors related to their use. The most promising studies were grounded in self-determination theory. Training and autonomy in the design of evidence-based assessment methods were positively related to their use, while negative stakeholder perceptions decreased practitioners’ intentions to use evidence-based assessment methods. Use of evidence-based decision-making procedures was positively related to access to such procedures, information to use it, and autonomy over the procedure, but negatively related to receiving outcome feedback. A review of the professional selection literature showed that the implementation of evidence-based assessment was hardly discussed. We conclude with an agenda for future research on encouraging evidence-based assessment practice

    A Tutorial on Mechanical Decision-Making for Personnel and Educational Selection

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    In decision-making, it is important not only to use the correct information but also to combine information in an optimal way. There are robust research findings that a mechanical combination of information for personnel and educational selection matches or outperforms a holistic combination of information. However, practitioners and policy makers seldom use mechanical combination for decision-making. One of the important conditions for scientific results to be used in practice and to be part of policy-making is that results are easily accessible. To increase the accessibility of mechanical judgment prediction procedures, we (1) explain in detail how mechanical combination procedures work, (2) provide examples to illustrate these procedures, and (3) discuss some limitations of mechanical decision-making
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