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141.
Relative efficiency of R&D activities: A cross-country study accounting for environmental factors in the DEA approach 总被引:1,自引:0,他引:1
This paper applies the production framework associated with the data envelopment analysis (DEA) method to evaluate the relative efficiency of R&D activities across countries. R&D capital stocks and manpower are treated as inputs while patents and academic publications are considered as outputs. A three-stage approach, which involves using DEA for evaluating efficiency and using Tobit regressions for controlling the external environment, is applied to 30 countries in recent years. The results show that less than one-half of the countries are fully efficient in R&D activities and that more than two-thirds are at the stage of increasing returns to scale. Most countries have a more significant advantage in producing SCI cum EI publications than in generating patents. 相似文献
142.
本文对秦始皇兵马俑博物馆室内采集的长短期降尘、大气悬浮颗粒物和彩绘漆层进行了SEM-EDX研究,在大气悬浮颗粒、短期和长期降尘中,含硫颗粒的粒径分别为0.9~22.8μm、1.0~29.0μm和1.2~37.7μm,多为石膏与粘土或石英以内部混合的状态存在。降尘中的附着型絮状硫酸钙多于大气悬浮颗粒物中,显示降尘和大气中的二氧化硫发生了累进的化学反应。彩绘漆层表面的坑和裂隙附近观察到原位生长的硫酸钙晶体,显示漆层材料或降尘颗粒物与大气二氧化硫之间的酸化学反应,可能是彩绘漆层表面受侵蚀形成微小坑和裂隙的原因之一。 相似文献
143.
紧生成l—群的一个结构定理 总被引:1,自引:0,他引:1
吕新民 《商丘师范学院学报》2001,17(6):53-54
l-群G称为紧生成的,如果对于G的任意子集{αλ|λ∈Λ}且α=∨λ∈Λαλ存在,必存在{αλ|λ∈Λ}的有限子集a1、a2……an,使得a=∨ni=1ai。主要结果是:G∈F,则G是紧生成的当且仅当G的任一个l-子群是闭的,且Г(G)满足极小条件。 相似文献
144.
Research Findings. The present study examined relations between social-cognitive skills, aggression, and social competence using teacher questionnaires and tabletop tasks with preschool and kindergarten children. It was hypothesized that the acquisition of a theory of “mind”, as indexed by an understanding of false beliefs, might be related to social behavior for this age group. Overall, results indicated that both generation of forceful solutions in a traditional social-problem solving task and performance on the false belief tasks were significantly related to social competence, after controlling for the effects of age, language comprehension, and teacher ratings of aggression. In addition, theory of mind understanding was a better predictor of social competence than performance on a more traditional social information-processing task that involved the generation of alternative solutions to interpersonal problems. Practice. The implications of these findings for preschool and kindergarten peer relations and their potential relevance to treatment of deficits in social skills are discussed. Specifically, training in an understanding of counterfactual thinking (e.g., through increased and structured opportunities to engage in pretend play and storytelling) may enhance preschooler social skills. 相似文献
145.
Richard L. Venezky 《Journal of Science Education and Technology》2001,10(1):17-30
The application of information and computer technology (ICT) to education, particularly when ICT is a component of a major school reform, raises difficult issues for program evaluation. In many cases even defining the program goal is difficult because so many different changes are often instituted at the same time: installation of a local area network, development of technical support, staff development for integrating ICT into the curriculum and for new teaching methods, and so on. To assist program developers and evaluators in gaining control of such complex interventions in education, two basic procedures are described: the history of the future and program logic mapping. The former is a goals and methods clarification scheme, built around a press release that describes at the projected end of the project what was achieved and how. The latter procedure draws on the goals defined in the history of the future, along with the project strategy, to make explicit all of the major links between project inputs and project outputs. This map then serves as a guide for planning an evaluation that would verify causal linkages as well as outcomes. For each type of node in such a diagram, appropriate evaluation techniques are defined. 相似文献
146.
This study examined the factor structure of the Emotional Autonomy Scale (EAS) as proposed by Steinberg and Silverberg. Participants were from three independent samples of adolescents in grades 6 (n = 1,842), 8 (n = 1,769), and 10 (n = 1,232), with each sample consisting of three ethnic groups: African American, European American, and Mexican American. None of the confirmatory factor analyses for these samples supported the factor structure proposed by Steinberg and Silverberg. From the three models tested, the EAS is best described by the four originally proposed factors, combined with two method factors, one consisting of the positively worded scale items and one consisting of the negatively worded scale items. Results show that the EAS exhibits poor construct validity and behaves quite differently for the different grade and ethnic groups. The strong impact of method variance on the factor structure is discussed. Although various alternative solutions to the psychometric problems in the EAS are proposed, the most credible solution may be to reexamine the conceptual foundations of emotional autonomy and develop better measures of those concepts for adolescents. 相似文献
147.
OBJECTIVE: A model was examined in which the association between a parent's history of abuse and the parent's own abusive behavior toward his or her children was hypothesized to be mediated by parental psychopathology, early childbearing, and consistency of discipline. Additionally, the effect of severity of abuse on the likelihood of becoming abusive was examined. METHOD: Participants were 109 parents (G1) and their male children (G2) who were involved in a longitudinal study. The G1 parents reported on their own experiences of abuse when they were children. Ten years later, the G2 youths reported on the G1 parents' abusive behavior toward them. A number of other factors, including parental socioeconomic status (SES), antisocial behavior, depression and Post-traumatic Stress Disorder (PTSD), consistency of discipline, and the perceived early difficulty of the G2 children were measured. RESULTS: As reported by their own children, parents who reported having been abused in childhood were significantly more likely to engage in abusive behaviors toward the next generation. Findings indicated that abuse experienced by the parents, as well as consistency of discipline and depression plus PTSD, were predictive of parental abuse of the child. Contrary to hypotheses, the effects were not fully mediated. However, there were significant interactions between parental history of abuse and consistency of discipline, as well as abuse history and depression and PTSD. Parents who had experienced multiple acts of abuse and at least one physical impact were more likely to become abusive than were the other parents. CONCLUSIONS: The implications of these findings for preventive interventions are discussed. 相似文献
148.
Komesaroff L 《Journal of deaf studies and deaf education》2001,6(4):299-314
This article describes a case study of an Australian deaf facility and its changes in language policy. The study documents the process of change in a school community as the researcher worked collaboratively with teachers and parents to investigate the place of Auslan and bilingual pedagogy in deaf education. Teachers' dissatisfaction with educational outcomes and current practices propelled the discussion about language policy. Gaining the support of parents is a key feature of this study. Beliefs about language policy and practices are explored and the implications for change investigated. This is part of a larger study of deaf education and the politics of language practices (see Komesaroff, 1998). 相似文献
149.
Are mathematics disabilities due to a domain-general or a domain-specific working memory deficit? 总被引:12,自引:0,他引:12
The relationship between verbal and visual-spatial working memory and mathematical computation skill was examined in children and adults with and without disabilities in mathematics. A hierarchical regression analysis showed that, when partialing for the influence of reading ability, age, and gender, mathematical computation was better predicted by verbal than by visual-spatial working memory. Furthermore, the results showed that the relationship between mathematics ability and working memory were not significantly moderated by age but were stable across a broad age span. We concluded that, regardless of age, deficits in mathematics are mediated by both a domain-general and a domain-specific working memory system. 相似文献
150.
Margo. L. Brewer Gisela van Kessel Brooke Sanderson Fiona Naumann Murray Lane Alan Reubenson 《高等教育研究与发展》2019,38(6):1105-1120
ABSTRACTThe health, wellbeing and employability of university students are key considerations within higher education. In response, interest in student resilience is on the rise. Reviews of contemporary resilience literature highlight both conceptual and methodological weaknesses, issues which hamper attempts to design effective resilience interventions. To inform the design of a student resilience program, to be piloted at three Australian universities, a scoping review of resilience specific to the higher education context was undertaken. Searches of three electronic databases (PsychINFO, CINAHL and ProQuest) were conducted. Seventy-two peer-reviewed articles published between 2007 and 2017 were included in the review. While the review reaffirms the conceptual and methodological issues found in previous resilience research, it provides a useful critique of key issues in relation to university student resilience and interventions to enhance students’ resilience. Recommendations for educators and researchers are provided. 相似文献