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41.
With advanced prediction modes of intra prediction, intra coding of H.264/AVC offers significant coding gains compared with previous video coding standards. It uses an important tool called Lagrangian rate-distortion optimization (RDO) technique to decide the best coding mode for a block, but the computational burden is extremely high. In this paper, we proposed an improved fast intra prediction algorithm including block type selection and mode decision algorithm based on analysis of edge feature of a block. Our algorithm filters out unlikely block type and candidate modes to reduce the RDO calculations. Experimental results showed that the proposed algorithm can reduce the computation complexity of intra prediction from 52.90% to 56.31%, with 0.04 dB PSNR degradation and 2% increase of bit rate. 相似文献
42.
A clinical task-based interview can be seen as a situation where the interviewer–interviewee interaction on a task is regulated
by a system of explicit and implicit norms, values, and rules. This paper describes how documenting and mapping triadic interaction
among the interviewer, the interviewee, and the knowledge negotiated can be used to increase procedural replicability of the
interview and accuracy of drawn conclusions about the interviewee’s thinking process. Excerpts from interviews with 25 inservice
mathematics teachers working on a task to make up a problem whose solution requires division of two fractions are discussed.
The excerpts illustrate the relationship between methodological decisions taken by the interviewer during the interview and
the applicability of the interview output to the research questions. A divergent analysis of the interviews with these teachers,
which spanned over two years and were conducted by four interviewers, is used to offer a framework for analyzing data collected
in clinical task-based interviews. 相似文献
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ABSTRACTBlended learning has been a feature of higher education practice and research for almost two decades. This article takes stock of current blended learning research, contributing to the growing number of meta-analyses of higher education and blended learning research more generally, through a review of ninety-seven articles relating to blended learning in higher education published in fifteen journals between 2012 and mid-2017. The review focused on where and when the articles were published; their provenance, scale, scope; methodological approach; the broad research themes; and definition of blended learning used. The review shows that despite its ubiquity, blended learning’s definition is all-encompassing; its spread is global but research is dominated by key players; it is of technical interest; and its research is small-scale, individually focused, seeking to evidence the benefits of blended learning. The article concludes with recommendations of how higher education research could provide institutions with evidence to ensure their ‘best of blends’. 相似文献
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McCurdy K 《Child abuse & neglect》2005,29(3):251-268
OBJECTIVES: This study examines an expanded version of Belsky's (1984) multi-dimensional process model of parenting to determine whether changes in stress and support influence maternal attitudes during the first year of a child's life. METHOD: Data were collected from mothers of newborns eligible for Hawaii's Healthy Start program who had been randomly assigned to home visitation (n=108) or control (n=104) status. Multiple regression analyses were used to test hypotheses regarding the influence of change in contextual sources of support and stress on parenting attitudes as measured by the Child Abuse Potential Inventory (CAPI) Abuse Scale. A post hoc analysis of variance was conducted to explore interactions among the predictor variables and home visitation. RESULTS: Stress in the form of change in public assistance status led to more punitive parenting attitudes while increased support from the partner and from close associates emerged as significant predictors of less punitive parental attitudes. The exploratory analyses suggest that home visitation may moderate the impacts of stress and support on maternal attitudes. CONCLUSIONS: In line with Belsky's (1984) process model of parenting, increased stress adversely impacted maternal attitudes regarding physical punishment while increased support exerted favorable effects. The results also support further elaboration of Belsky's model including the expansion of marital support to include unmarried partners and the need to consider the impact of formal support sources on parenting. 相似文献
46.
1IntroductionBackground subtraction methods are extensively ex-ploited for moving object detection in videos in manyapplications ,such as traffic monitoring[1],human mo-tion capture[2]and video surveillance[3]. The centralidea behind such methods is to segment foreground ini mage sequences taken from a fixed camera by com-paring each newframe to a model of the scene back-ground . Therefore , correctly and efficiently modelingand updating the background model is one of the mostchallenging aspec… 相似文献
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Takashi Sagawa 《浙江大学学报(A卷英文版)》2018,19(1):80-85
Composite materials of Fe/Al2O3, which consist of small particles of iron supported by thermally stable alumina even at 500–700 °C, have been widely used in the water-gas shift reaction for natural gas reforming. Therefore, Fe/Al2O3 is one of the promising candidates for re-transformation of exhausted CO2 into fuels such as alcohols and hydrocarbons. The development of a CO2 reforming system using the composite materials of Fe/Al2O3 through CO2 reduction to CO, dissociation of water into hydrogen, and methanol synthesis has been investigated. It was found that dry and steam (i.e. wet) reforming of CO2 produced almost the same amount of CO. At a temperature above 500 °C, maximal and saturated yields of CO and H2 from CO2 and water were obtained. However, this CO2 reforming system requires higher-pressure conditions from several tens to hundreds standard atmospheric pressure in order to achieve high yield and selectivity for methanol production. In this study we developed the modified CO2 reforming system by the utilization of Ni and/or Cu instead of Fe in order to obtain other types of useful products such as CO, CH4, and carbon, more efficiently and selectively under atmospheric pressure. When Ni or Cu was used, conversion of CO2 was reduced to 76%, while 9% of methane was detected in the case of Ni. On the other hand, though the CO2 conversion reduced half of the Fe, the selectivity of CO from CO2 increased to 95% in the case of Cu. 相似文献
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