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61.
National educational standards (NES) were released in Germany 2003/2004 as obligatory performance standards substantively and normatively defining an acceptable degree of proficiency. The NES describe tangible competencies in the form of can-do statements for core subjects to be acquired by students at the end of defined stages of schooling. To evaluate standards-based performances the Standing Conference of the Ministers of Education and Cultural Affairs of the Federal States in Germany (KMK) implemented a test-based monitoring system that comprised a centralized evaluation in a nationwide study sample comparing the German federal states (Ländervergleich), as well as state-wide testing schemes at the end of grade 3 and grade 8 linked to the NES. All test items were designed by didactic experts on the basis of domain specific competence models that were psychometrically evaluated. The potential practical benefit from competence testing is discussed for the various system levels of feedback (state, school, teacher, and student). It is argued that, in order to tap the full potential of standards-based performance feedback, it must be appropriately communicated to the target system level and should be accompanied by suitable measures of action support.  相似文献   
62.
Despite the rising implementation of RFID technology-based healthcare services, few empirical studies have been conducted to assess the potential of this technology within the healthcare sector. The purpose of this study is to help initiate and direct such empirical research by both conducting a review of the extant literature and using the findings to provide a discussion of current trends and future directions in this domain. In this paper, we develop a conceptual framework that can be used to classify publications on RFID applications and issues in the healthcare industry. We then use this framework to systematically summarize relevant articles. We conclude by highlighting future research directions where the deployment of RFID technology is likely to transform the healthcare sector.  相似文献   
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64.
We analyze a recently introduced approach for the sorting of aqueous drops with biological content immersed in oil, using a microfluidic chip that combines the functionality of electrowetting with the high throughput of two-phase flow microfluidics. In this electrostatic sorter, three co-planar electrodes covered by a thin dielectric layer are placed directly below the fluidic channel. Switching the potential of the central electrode creates an electrical guide that leads the drop to the desired outlet. The generated force, which deflects the drop, can be tuned via the voltage. The working principle is based on a contrast in conductivity between the drop and the continuous phase, which ensures successful operation even for drops of highly conductive biological media like phosphate buffered saline. Moreover, since the electric field does not penetrate the drop, its content is protected from electrical currents and Joule heating. A simple capacitive model allows quantitative prediction of the electrostatic forces exerted on drops. The maximum achievable sorting rate is determined by a competition between electrostatic and hydrodynamic forces. Sorting speeds up to 1200 per second are demonstrated for conductive drops of 160 pl in low viscosity oil.  相似文献   
65.
Cut‐scores were set by expert judges on assessments of reading and listening comprehension of English as a foreign language (EFL), using the bookmark standard‐setting method to differentiate proficiency levels defined by the Common European Framework of Reference (CEFR). Assessments contained stratified item samples drawn from extensive item pools, calibrated using Rasch models on the basis of examinee responses of a German nationwide assessment of secondary school language performance. The results suggest significant effects of item sampling strategies for the bookmark method on cut‐score recommendations, as well as significant cut‐score judgment revision over cut‐score placement rounds. Results are discussed within a framework of establishing validity evidence supporting cut‐score recommendations using the widely employed bookmark method.  相似文献   
66.
The purpose of this study was to evaluate the relationship between the physicochemical properties of saliva such as flow rate, pH, buffering capacity, calcium level, total protein and total antioxidant levels in caries free and caries active children. The present study included one hundred and twenty healthy children who were divided into two groups; group I and group II comprising of age groups 7–10 and 11–14 years, respectively. Both the groups were then sub-divided equally according to gender. They were further divided into caries free and caries active with 15 children in each group. Unstimulated saliva was collected by suction method and flow rates were determined. The samples were then analyzed for pH, buffering capacity, total protein, calcium and total antioxidant capacity. The data was statistically analyzed using student t test (unpaired). The results revealed that when all these parameters were compared among the caries free and caries active children, flow rate, pH, buffering capacity were slightly reduced in caries active children, but total protein and total antioxidant capacity of saliva increased significantly in caries active children and the total calcium decreased significantly in caries active children. Within the limitation of this study, we conclude that, the physicochemical properties of saliva play a major role in the development of caries.  相似文献   
67.
教育中的优异、公平和多样性   总被引:1,自引:0,他引:1  
Will.  CV 《教育展望》2000,(4):35-43
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69.
It is well known that a fractional-order system with a continuous right hand side does not have finite-time stable equilibria, but the discontinuous case has remained elusive in literature. Thus, based on novel mathematical tools, recently published in literature, it is demonstrated that attaining finite-time stable equilibria is not possible for a fractional-order system, not even in the case of an impulsive or discontinuous feedback. In consequence, it is demonstrated that, for a fractional-order system, a Lyapunov stable equilibrium cannot be at the same time finite-time stable.  相似文献   
70.
The modeling of understanding consumers buying behavior requires a technique, which does not only incorporate the preferences of the consumers but also have the ability to trade-off between multi-characteristics products and services. This study is supported by evaluating a framework via a marketing research technique of Conjoint Analysis wherein we have shown how certain attributes of mobile phones when studied jointly can affect the overall buying behavior of the youth towards various brands taken into consideration. Further, customers' choice probabilities of the mobile phones, based on preferences have been evaluated and potential market size is determined. Also, this study has determined and forecasted the sales on the basis of choice probability and utility obtained via conjoint analysis. Customers of the mobile phone located in Delhi have been targeted for this study.  相似文献   
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