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121.
The effect of self-modeling as an intervention to increase individual participatory behavior in the classroom was investigated using a multiple baseline design across three second grade students with a follow-up. In addition, a control student was employed to further investigate the effects of the intervention. Self-modeling is defined as the positive change in behavior resulting from spaced viewing of oneself on edited tapes depicting exemplary behavior. Students viewed edited videotapes of themselves successfully volunteering to participate in class by raising their hand. The three students, during baseline, had a mean participation rate ranging between 8% and 24% compared with the control student's rate ranging between 53% and 63%. During intervention, the mean participation rate ranged between 28% and 60% compared with the control student's rate ranging between 43% and 46%. At follow-up, students had a mean percentage rate ranging between 44% and 64% compared with the control student's rate of 53%. Thus, they more closely approximated or surpassed the control student's mean rate of participation during intervention and follow-up, suggesting that the self-modeling intervention was effective in increasing individual participatory behavior in the classroom. © 1998 John Wiley & Sons, Inc.  相似文献   
122.
Part of the controversy about allowing examinees to review and change answers to previous items on computerized adaptive tests (CATs) centers on a strategy for obtaining positively biased ability estimates attributed to Wainer (1993) in which examinees intentionally answer items incorrectly before review and to the best of their abilities upon review. Our results, based on both simulated and live testing data, showed that there were instances in which the Wainer strategy yielded inflated ability estimates as well as instances in which it yielded deflated ability estimates. The success of the strategy in inflating ability estimates depended on the ability estimation method used (maximum likelihood versus Bayesian), the examinee's true ability level, the standard error of the ability estimate, the examinee's ability to implement the strategy, and the type of decision made from the ability estimate. We discuss approaches to dealing with the Wainer strategy in operational CAT settings.  相似文献   
123.
Lean six sigma is a management methodology that firms can employ to achieve substantial improvement in supply chain performance. However, few pedagogical exercises facilitate students’ use of a comprehensive set of lean six sigma principles within a supply chain context. We describe the Airplane Supply Chain Simulation that helps students understand how lean six sigma concepts may be leveraged to improve supply chain performance. The basis of this simulation is a four‐tier supply chain, consisting of suppliers (two tiers), a manufacturer, and a customer, that produces three models of paper airplanes to meet randomly distributed customer demand. In the first of three successive runs, a highly structured simulation is executed in which supply chain roles are well defined, material flows are convoluted, and a “push” production strategy is followed. The first simulation as the “current state” and, for the second and third simulation runs, challenge competing student teams to leverage lean six sigma concepts to develop a “future state” that enables the fulfillment of all customer orders at the lowest cost. Results based on statistical analyses of survey response data from 194 MBA students show that the Airplane Supply Chain Simulation is an effective participative, team‐based learning tool.  相似文献   
124.
We demonstrate the method of non-inertial lift induced cell sorting (NILICS), a continuous, passive, and label-free cell sorting approach in a simple single layer microfluidic device at low Reynolds number flow conditions. In the experiments, we exploit the non-inertial lift effect to sort circulating MV3-melanoma cells from red blood cell suspensions at different hematocrits as high as 9%. We analyze the separation process and the influence of hematocrit and volume flow rates. We achieve sorting efficiencies for MV3-cells up to EMV3 = 100% at Hct = 9% and demonstrate cell viability by recultivation of the sorted cells.  相似文献   
125.
In this paper a new integrated observer-based fault estimation and accommodation strategy for discrete-time piecewise linear (PWL) systems subject to actuator faults is proposed. A robust estimator is designed to simultaneously estimate the state of the system and the actuator fault. Then, the estimate of fault is used to compensate for the effect of the fault. By using the estimate of fault and the states, a fault tolerant controller using a PWL state feedback is designed. The observer-based fault-tolerant controller is obtained by the interconnection of the estimator and the state feedback controller. We show that separate design of the state feedback and the estimator results in the stability of the overall closed-loop system. In addition, the input-to-state stability (ISS) gain for the closed-loop system is obtained and a procedure for minimizing it is given. All of the design conditions are formulated in terms of linear matrix inequalities (LMI) which can be solved efficiently. Also, performance of the estimator and the state feedback controller are minimized by solving convex optimization problems. The efficiency of the method is demonstrated by means of a numerical example.  相似文献   
126.
Research and development (R&D) investment activity plays a crucial role in developing high-tech industries. In recent decades, China has made sustained investments in its domestic high-tech industries, with the goal of increasing their productivity. This paper investigates the effect of this investment on relative R&D efficiency across China's high-tech sectors. Data Envelopment Analysis (DEA) was used to generate quantitative indices for sector comparisons. The analysis of this study indicates that overall R&D investment efficiency did not increase from 1998 to 2009, despite R&D expenditure increasing by 2188%. Over the same period, most sectors suffered from decreasing returns to scale (DRS), presumably also reflecting the inefficient R&D investment. Most of the sectors showed significant fluctuation on R&D investment efficiency. This research result indicates that the problem of China's high-tech industry may be from the inefficiency of its technology commercialization processes, and therefore represents a critical parameter for policy makers and managers.  相似文献   
127.
Unilateral enterprise resource planning (ERP) curriculum improvements from the instructor's perspective are likely to generate only limited success. Understanding student motivations and beliefs with ERP systems is the missing link to effective ERP education. Relatively little attention in the ERP literature has been given to student learning associated with ERP experience, and almost none to factors influencing current and expected student beliefs and behaviors relative to ERP. The complexity of ERP systems demands that beliefs and behaviors be considered when planning ERP curricula. In the present study, the Theory of Planned Behavior was extended to examine students’ intentions to explore additional aspects of ERP after their class exercises. When considering all students, attitude and subjective norm had positive and significant effects on intentions to continue ERP learning. Subjective norm also affected attitude, and availability of support materials had a positive effect on subjective norm. Distinctive patterns are found for the construct relationships between student groups who valued ERP education (the engaged) and those who placed little or no value on ERP education (the undecided). Results from competing model analyses indicate that support materials influenced the engaged and undecided groups differently. Strategies for ERP curriculum design are provided.  相似文献   
128.
We analyze the impact of exercising sports during childhood and adolescence on educational attainment. The theoretical framework is based on models of allocation of time and educational productivity. Using the rich information from the German Socio-Economic Panel (GSOEP), we apply generalized ordered probit models to estimate the effect of participation in sport activities on secondary school degrees and professional degrees. Even after controlling for important variables and selection into sport, we find strong evidence that the effect of sport on educational attainment is statistically significant and positive.  相似文献   
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