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1.
The present study investigates the emotional experience, expression, and regulation processes of high-quality Japanese elementary school teachers while they interact with children, in terms of teachers’ emotional competence. Qualitative analysis of interview data demonstrated that teachers had various emotional experiences including self-elicited negative emotions. The major expression patterns were identified as direct staging and the suppression of emotions. Teachers considered emotion expression in front of children as a skill, and their emotion regulation processes involved considering various purposes, appropriately using emotion expression, and ideal teacher images. The findings suggest that high-quality teachers effectively use emotional competence in teaching.  相似文献   
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In one study, parameters were estimated for constructed-response (CR) items in 8 tests from 4 operational testing programs using the l-parameter and 2- parameter partial credit (IPPC and 2PPC) models. Where multiple-choice (MC) items were present, these models were combined with the 1-parameter and 3-parameter logistic (IPL and 3PL) models, respectively. We found that item fit was better when the 2PPC model was used alone or with the 3PL model. Also, the slopes of the CR and MC items were found to differ substantially. In a second study, item parameter estimates produced using the IPL-IPPC and 3PL-2PPC model combinations were evaluated for fit to simulated data generated using true parameters known to fit one model combination or ttle other. The results suggested that the more flexible 3PL-2PPC model combination would produce better item fit than the IPL-1PPC combination.  相似文献   
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ZVS(zero voltage switching) PWM(pulse width modulation) inverters have attracted much attention recently. The basic idea is to use ZVS circuit as the main circuit of inverter resonance at the beginning of every carrier period so that each power device can commutate when voltage of the main circuit's DC bus line is zero. To ensure the resonant circuit to operate properly, sawtooth with alternate slope (positive or negative) is used as carrier. But the time of zero voltage vectors with such PWM pattern is greatly different from traditional hard-switching PWM pattern. This paper discusses the locus of flux linkage under soft-switching PWM pattern by using space voltage vector. It is pointed out that, under the hard-switching PWM pattern, speed of flux linkage is adjusted by zero space voltage vector. When soft-switching PWM pattern is used, however, effective time of space voltage vector varies considerably, sometimes even without zero space voltage vector. Therefore non-zero space voltage vector has been used to make the speed of flux linkage locus equal to that of hard-switching PWM pattern. The cause of current distortion in soft-switching PWM inverters is also discussed. Based on the flux linkage locus circle, corresponding compensation methods are proposed. Experimental results show that the described method can effectively improve output current waveform of inverter.  相似文献   
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日本大学图书馆期刊价格上涨对策研究   总被引:11,自引:0,他引:11  
通过分析日本大学图书馆面对期刊价格上涨所采取的一系列措施,希望对中国的图书馆应对期刊价格上涨问题起到参考作用。  相似文献   
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Reading and Mathematics tests of multiple-choice items for grades Kindergarten through 9 were vertically scaled using the three-parameter logistic model and two different scaling procedures: concurrent and separate by grade groups. Item parameters were estimated using Markov chain Monte Carlo methodology while fixing the grade 4 population abilities to have a standard normal distribution. For the separate grade-groups scaling, grade groupings were linked using the Stocking and Lord test characteristic curve procedure. Abilities were estimated using the maximum-likelihood method. In either content area, scatterplots of item difficulty, discrimination, and ability estimates from the two methods showed consistently strong linear relationships. However, as grade deviated from the base grade of four, the best-fit linear line through the pairs of item discriminations started to rotate away from the identity line. This indicated the discrimination estimates from the separate grade-groups procedure for extreme grades to be, on average, higher than those from the concurrent analysis. The study also observed some systematic change in score variability across grades. In general, the two vertical scaling approaches yielded similar results at more grades in Reading than in Mathematics.  相似文献   
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The origin(s) and role(s) of metal soaps in paints are a worldwide concern today. These hybrid compounds, containing both fatty acid chains and metals associated with a carboxylate function, are increasingly identified in paints. As reviewed in the first part of this work, the presence of metal soaps in paints is differently interpreted in scientific publications: metal soaps are sometimes considered to play a positive role as anchor points, during paint drying processes; they can also be considered as responsible for many degradation processes (protrusions, efflorescences, darkening, etc.). Their origins are also interpreted in various ways. In some paintings (in particular from the twentieth century), they have sometimes introduced on purpose, as additives, to modify the physical properties of the painting materials. In older paintings, metal soaps are usually thought to result from an uncontrolled reaction of oil with lead-based pigments, in particular lead white, red lead, and lead tin yellow. In the second part of this work, the review of historical recipes of lead-based paint shows an important number of recipes based on controlled mixing of oil with lead driers. In the third part, the experimental reproduction of such traditional recipes using walnut oil and litharge (PbO) shows that lead soaps can be formed, both in about one hour at ~100°C, or in about one month at room temperature. It shows as well that after a few years, litharge is no longer detected in the paint medium, while different lead carbonates are. Finally, the micro-infrared spectroscopy and micro-X-ray diffraction re-analysis of protrusions from a nine-year model painting shows together with lead soaps, the presence of Pb5(CO3)3(OH)2O (‘synthetic plumbonacrite’), an unusual phase recently observed in a protrusion from a painting by Vincent Van Gogh. This work highlights (i) the multiple origins and roles of metal soaps in paints and (ii) the importance of combining the analysis of fragments from historical paintings with the analysis and reproduction of historical recipes. In particular, we show that the components detected today in historical paintings may severely differ from those originally used or prepared by the painter, complicating the assessment of the painter's intentions. More than the presence of metal soaps, the key questions to be tackled should be about their origins and (re)mobilization.  相似文献   
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