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Computer-based testing – is an effective teacher’s tool, intended to optimize course goals and assessment techniques in a comparatively short time. However, this is accomplished only if we deal with high-quality tests. It is strange, but despite the 100-year history of Testing Theory (see, Anastasi, A., Urbina, S. (1997). Psychological testing. Upper Saddle River, NJ: Prentice-Hall) there still exist some misconceptions. Modern wide-spread systems for computer based course management and testing reveal a set of problems corresponding to certain features of testing methods.  相似文献   
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Scenarios are possible future states of the world that represent alternative plausible conditions under different assumptions. Often, scenarios are developed in a context relevant to stakeholders involved in their applications since the evaluation of scenario outcomes and implications can enhance decision-making activities. This paper reviews the state-of-the-art of scenario development and proposes a formal approach to scenario development in environmental decision-making. The discussion of current issues in scenario studies includes advantages and obstacles in utilizing a formal scenario development framework, and the different forms of uncertainty inherent in scenario development, as well as how they should be treated. An appendix for common scenario terminology has been attached for clarity. Major recommendations for future research in this area include proper consideration of uncertainty in scenario studies in particular in relation to stakeholder relevant information, construction of scenarios that are more diverse in nature, and sharing of information and resources among the scenario development research community.  相似文献   
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Musculoskeletal disorders (MSDs) affect much of the workforce and remain a major form of occupational ill health. With a view to improving the efficacy of interventions, this review examined preventative actions relating to these disorders. A detailed analysis grid was used to classify the information contained in the 47 reviewed articles whose common aspect was to report actions carried out in the workplace that led to the implementation of changes to prevent MSDs. The analysis identified and characterized three major categories of intervention processes in MSD prevention: the complete type (n=17), the shortened type (n=16), and the turnkey type (n=14). These three groups of intervention processes were differentiated by their approaches and their contexts of application. The result was important differences in the changes implemented. Because of the variability in intervention processes and possible impacts on MSD prevention, a proposal to "delimit" these processes so as to improve their effectiveness is presented.  相似文献   
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Algebraic techniques are used to prove that any circuit constructed with MOD q gates that computes the AND function must use (n) gates at the first level. The best bound previously known to be valid for arbitraryq was (logn).  相似文献   
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A thermal model was built to account for the effects of geometrical parameters of sheet specimen, process parameters and material parameters on the temperature increase of the sheet specimen in Electricity-Assisted Incremental Sheet Forming (EISF). In the EISF, the local area of sheet specimen contacting with a forming tool is heated by direct current, which flows through the forming tool to the sheet specimen. EISF experiments of two high strength steel sheets were carried out to validate the thermal model. The thermal model can be integrated into the control program of EISF system to achieve more accurate temperature control.  相似文献   
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The aqueous-core enclosed in lipid nanoballoons integrating multiple emulsions of the type water-in-oil-in-water mimic, at least in theory, the environment within viable cells, thus being suitable for housing hydrophilic protein entities such as bioactive proteins, peptides and bacteriophage particles. This study reports a complete physicochemical characterization of optimized biomimetic aqueous-core lipid nanoballoons housing hydrophilic (BSA) protein entities, evolved from a statistical 23×31 factorial design study (three variables at two levels and one variable at three levels) that was the subject of the first paper of a series of three, aiming at complete stabilization of the three-dimensional structure of protein entities attempted via housing the said molecular entities within biomimetic aqueous-core lipid nanoballoons integrating a multiple (W/O/W) emulsion. The statistical factorial design followed led to the production of an optimum W/O/W multiple emulsion possessing quite homogeneous particles with an average hydrodynamic size of (186.2?±?2.6) nm and average Zeta potential of (?36.5?±?0.9) mV, and exhibiting a polydispersity index of 0.206?±?0.014. Additionally, the results obtained for the diffusion coefficient of the lipid nanoballoons integrating the optimized W/O/W multiple emulsion were comparable and of the same order of magnitude (10?12 m2 s?1) as those published by other authors since, typically, diffusion coefficients for molecules range from 10?10 to 10?7 m2 s?1, but diffusion coefficients for nanoparticles are typically of the order of magnitude of 10?12 m2 s?1.  相似文献   
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