基于核密度估计多样性采集的背景建模算法

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…     

Beyond words: the importance of gesture to researchers and learners

Gesture has privileged access to information that children know but do not say. As such, it can serve as an additional window to the mind of the developing child, one that researchers are only beginning to acknowledge. Gesture might, however, do more than merely reflect understanding-it may be involved in the process of cognitive change itself. This question will guide research on gesture as we enter the new millennium. Gesture might contribute to change through two mechanisms which are not mutually exclusive: (1) indirectly, by communicating unspoken aspects of the learner's cognitive state to potential agents of change (parents, teachers, siblings, friends); and (2) directly, by offering the learner a simpler way to express and explore ideas that may be difficult to think through in a verbal format, thus easing the learner's cognitive burden. As a result, the next decade may well offer evidence of gesture's dual potential as an illuminating tool for researchers and as a facilitator of cognitive growth for learners themselves.     

Hearing Words,Learning Words: How Different Presentations of Novel Vocabulary Words Affect Children’s Incidental Learning

Research Findings: Children learn most of their vocabulary incidentally, by hearing words used in their environment. This study explored which kinds of presentations of words, without any direct instruction, yielded greater depth of target word knowledge. Changes in 56 kindergartners’ depth of knowledge for each of 23 novel target words (N = 1,288) based on presentation in 1 of 3 conditions (read-aloud, teacher conversation, or both read-aloud and conversation) were explored and compared to control words that were never presented. A 2-level, cross-classification analysis modeled the postintervention score for each word for each child. Children’s word meaning knowledge improved most when words were presented via combined conversations and read-alouds. Vocabulary gains for words presented via conversations differed across classrooms. Practice or Policy: Both teacher conversations and read-aloud presentations of target vocabulary should be used together. Professional development for teachers’ effective vocabulary conversations may be needed.     

Histories of Romani Education in Slovakia: A Kazamian Perspective

Using the critical work of Andreas Kazamias on the history and methods of comparative education as conceptual framework, we investigate the education (over a 200-year period) of the Slovak Roma. We position our story as paradigmatic of the dual processes of enlightenment and obscurantism with which we are familiar in thinking about the history of racial violence. The article describes the encounter of a young British doctor, Richard Bright, with Roma and Slovaks in 1814, and explores the Enlightenment thinking about Roma in specific, and race in general, in Bright’s travelogue. We juxtapose these historical investigations with qualitative findings from research conducted recently in the same region of Slovakia. Our goal is to show that Kazamias’s calls for a return to the historical in educational research, and greater attention to the “paideia of the soul,” have relevance in considering the discouraging past and present of Roma in Slovak schools and society.     

THE DELPHI: EDUCATION AND ASSESSMENT IN INSTITUTIONAL GOAL SETTING

This paper describes and analysies the use of a delphi research methodology to assess faculty perceptions of institutional needs and goals in an osteopathic medical education program. Use of the delphi to educate faculty in the administrative and political functioning of the institution as well as to involve all faculty in the refinement of specific needs and goals is discussed. Full‐time clinical and basic science faculty of the New Jersey School of Osteopathic Medicine provided an example of the varied uses of the delphi research methodology in higher education and specifically in profesiional higher education. The three rounds of the delphi procedure produced faculty consensus on the following institutional variable items: (a) the philosophical and functional orientation of the curriculum; (b) location and design of the physical campus facilities and environment; (c) faculty issues of tenure, promotion, salary and merit; (d) teaching, and the evaluation of teaching; (e) student characteristics and admissions policies; and (f) administrative structure and communication networks.     

Conversion of CO<Subscript>2</Subscript> to useful substances with composite iron,nickel, and copper catalysts

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.