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1.
Knowledge discovery systems can be traced back to their origin, artificial intelligence and expert systems, but use the modern technique of data mining for the knowledge discovery process. To that end, the technical community views data mining as one step in the knowledge discovery process, while the non-technical community seems to view it as encompassing all of the steps to knowledge discovery. In this exploratory study, we look at medical knowledge discovery systems (MKDSs) by first looking at three examples of expert systems to generate medical knowledge. We then expand on the use of data abstraction as a pre-processing step in the comprehensive task of medical knowledge discovery. Next, we look at how performance of a medical knowledge discovery system is measured. Finally, the conclusions point to a bright future for MKDSs, but an area that needs extensive development to reach its full potential.  相似文献   
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A number of policy proposals have recently been presented that seek to address the problem of declining productivity growth. Many of these are aimed at encouraging private R&D spending through tax incentives. This paper first reviews some of these proposals, then evaluates tax incentives per se as a policy tool for encouraging R&D growth, and finally offers suggestions for redesigning R&D related tax incentive policies.  相似文献   
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Despite its frequent use, there is little understanding of the concept of differential among upper high school and undergraduate students of physics. As a first step to identify the origin of this situation and to revert it, we have done a historic and epistemological study aimed at clarifying the role and the meaning of the differential in physics and at improving curricular and teaching models in the sense of Gilbert et al. (Gilbert J.K., Boulter C., & Rutherford, M.: 1998a, International Journal of Science Education 20(1), 83–97, Gilbert J.K., Boulter C., & Rutherford, M.: 1998b, International Journal of Science Education 20(2), 187–203). We describe the contributions of Leibniz and Cauchy and stress their shortcomings, which are overcome by the alternative definition proposed by the French mathematician Fréchet, dating from early 20th century. As a result of this study, we answer to some fundamental questions related to a proper understanding of the differential in physics education (for 17–19 years old students).  相似文献   
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The first important monograph describing the battered child syndrome was written in 1860 by Ambroise Tardieu, a French forensic physician. Here is a translation of his article, published in the Annales d'hygiene publique et de medecine legale, with the title "Etude medico-legale sur les sevices et mauvais traitements exerces sur des enfants." The first part of his article is entirely translated. A brief summary of the 32 cases report described by Tardieu in the second part of his article is presented.  相似文献   
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Proficiency in fundamental motor skills (FMS) is important for both the health and the overall growth and development of young children. To identify factors that facilitate the development of FMS, the study provided preliminary data on the effect of videomodeling (VM) on the acquisition of FMS by typically developing young children. Participants were six conveniently selected typically developing preschool-age children from an early care and education center. A multiple-baseline-across-participants single-subject research design was used to evaluate VM effects. Motor skill acquisition was assessed with validated developmental sequences of the standing long jump and the overarm throw. The results demonstrated that the VM intervention improved participants’ FMS performance and the improvement was maintained even after the withdrawal of the VM, 2 weeks after the last VM session. Qualitative data collected via a self-report enjoyment scale and field notes with the instructors elicited four factors that might have affected participants’ performance: their attention and motivation to perform the task and the skill complexity and reproduction. The data suggest that VM may be an efficient strategy for teaching FMS to preschool-age children.  相似文献   
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School‐wide positive behavior support (SWPBS) is a systemic approach for implementing a proactive schoolwide discipline and for improving students’ academic and behavioral outcomes by targeting the school’s organizational and social culture. With a multilevel approach, the present study evaluates the relative effectiveness of SWPBS on teachers’ perceptions of the student behavior (N = 3,295) across schools, teachers, and children using a multilevel approach. We assessed teacher perception of student problem behavior five times during a 3‐year implementation of SWPBS in 23 Dutch schools. Multilevel analyses not only revealed a small increase in perceived prosocial behavior and a small decrease in problems with peers, but also different effects across children, teachers, and schools. Effects were stronger for girls and for students with higher severity of perceived problems at baseline. At teachers’ level, higher mean baseline severity of perceived problems was associated with the reduced impact of SWPBS on perceived emotional problems and problems with peers. At the school level, effects were stronger for regular schools as compared with special needs schools.  相似文献   
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This study investigated reciprocal relations between adolescents' physical aggression and their perceptions of peers' deviant behaviors and attitudes. Analyses were conducted on four waves of data from 2,290 adolescents (ages 10–16) from three urban middle schools. Autoregression models revealed reciprocal relations between peer factors (i.e., friends' problem behavior, peer pressure for fighting, friends' support for fighting) and adolescents' reporting of their aggressive behavior. Bidirectional relations were also found between peer pressure for fighting and adolescents' frequency of physical aggression based on teacher ratings. Findings were consistent across sex, grade, and time. Findings suggest that multiple dimensions of peers' behaviors uniquely play a role in the development of adolescents' aggression and have important implications for interventions to reduce problem behaviors.  相似文献   
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Using data from a nation-wide survey on Spanish workers, this paper examines two issues: the determinants of school choice (distinguishing between public and private schools) and the influence of school type on the individual’s educational attainment. For that, bivariate probit models are estimated. The analysis is carried out separately by gender and birth cohort. We find that individuals who have attended a private school come from households with higher socio-cultural level and that having attended a private school does not raise the probability of reaching a higher degree, once potential endogeneity of school choice and educational outcomes are taken into account. However, the latter result depends on the instrumental variable used for observed school type in models of demand for higher education.  相似文献   
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