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991.
In view of the risk of E-commerce and the response of the insurance industry to it, this paper is aimed at one important point of insurance, that is, estimation of financial loss ratio, which is one of the most difficult problems facing the E-insurance industry. This paper proposes a quantitative analyzing model for estimating E-insurance financial loss ratio. The model is based on gross income per enterprise and CSI/FBI computer crime and security survey. The analysis results presented are reasonable and valuable for both insurer and the insured and thus can be accepted by both of them. What we must point out is that according to our assumption, the financial loss ratio varied very little, 0.233% in 1999 and 0.236% in 2000 although there was much variation in the main data of the CSI/FBI survey. 相似文献
992.
This article is concerned with the extended homogeneous balance method for studying the abundant lacalized solution structure of the (2 1)-dimensional asymmetric Nizhnik-novikov-Veselov equation.A Baecklund transformation was first obtained.and then the richness of the localized coherent structures was found,which was caused by the entrance of two variable-separated arbitrary functions,in the model.For some spectial choices of the arbitrary functions,it is shown that the localized structures of the model may be dromions,lumps,and rinmg solitons. 相似文献
993.
Noise affects most of the activities. The term noise is used to describe fluctuations about the mean deterministic stationary value of a physical quantity. Noise is generally associated, for example, with inaccuracies in measurements or impurities in signals such as musical notes and hence is undesirable. However, its essential role in physical processes was pointed out in the beginning the last century by Smoluchowski and others. It is only in the last two decades or so that the positive (active) aspects of its role has come to light and is being subjected to intense scrutiny. It is now being increasingly realised that noise is an important ingredient to bring order in dynamical processes. Though it appears counterintuitive, noise seems to help in directing transport processes in biological systems at the molecular level. 相似文献
994.
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996.
The purpose of this study was to describe and understand the range of outcomes of class visits to natural history museums.
The theoretical framework is based on the multifaceted process of learning in free choice learning environments, and emphasizes
the unique and individual learning experience in museum settings. The study’s significance is in highlighting several possible
cognitive as well as non-cognitive learning effects in museums class visits, by providing the student’s point of view. Data
was collected by semi-structured interviews with 50 students in grades 6–8 on the day following the visit. We present evidence
that students expressed several learning outcomes, connected directly and indirectly to the scientific content of the visit.
Content oriented outcomes included acquiring scientific knowledge and making connections to prior knowledge; social oriented
outcomes were identified in students’ statements regarding communicating knowledge and social aspects of learning; and interest
oriented outcomes were evidenced by students’ expressions about emotions, interest and curiosity. The aggregate data addressed
the common outcomes and the impact of class visits to natural history museums in the short term. Comparisons between two types
of museums show significant differences in several aspects, regarding the exhibit and/or the activity type. Practical ideas
for structuring the ultimate experience are included. 相似文献
997.
The need to equip science teachers with knowledge, skills, and habits of mind to face the challenges of teaching science through
inquiry informed this study, which analyzed the secondary science intern teachers’ beliefs about inquiry before, during, and
following a series of 2 consecutive science methods courses in an attempt to document the effect of such experiences on their
ability and willingness to infuse science inquiry in their science curricula. Nine science credentialing interns participated
in the study. Data was gathered from their written reflections and various assignments throughout the methods courses. Results
suggested that their beliefs changed significantly after the science methods courses. The implications of the study to secondary
science teacher educators and researchers were highlighted. 相似文献
998.
Libby F. Gerard Jane B. Bowyer Marcia C. Linn 《Journal of Science Education and Technology》2008,17(1):1-18
Reforms such as technology-enhanced instruction require principal leadership. Yet, many principals report that they need help
to guide implementation of science and technology reforms. We identify strategies for helping principals provide this leadership.
A two-phase design is employed. In the first phase we elicit principals’ varied ideas about the Technology-enhanced Learning
in Science (TELS) curriculum materials being implemented by teachers in their schools, and in the second phase we engage principals
in a leadership workshop designed based on the ideas they generated. Analysis uses an emergent coding scheme to categorize
principals’ ideas, and a knowledge integration framework to capture the development of these ideas. The analysis suggests
that principals frame their thinking about the implementation of TELS in terms of: principal leadership, curriculum, educational
policy, teacher learning, student outcomes and financial resources. They seek to improve their own knowledge to support this
reform. The principals organize their ideas around individual school goals and current political issues. Principals prefer
professional development activities that engage them in reviewing curricula and student work with other principals. Based
on the analysis, this study offers guidelines for creating learning opportunities that enhance principals’ leadership abilities
in technology and science reform. 相似文献
999.
Metacognition and Self-Regulation in James,Piaget, and Vygotsky 总被引：3，自引：3，他引：0
This article investigates the intertwined constructs of metacognition and self-regulation as they emerge in the works and
theories of James, Piaget, and Vygotsky. To coordinate this exploration, we use an interpretive framework based on the relation
of subject and object. In this framework, James’s perspective on metacognition and self-regulation is aligned with the Self,
Piaget’s with the other and object, and Vygotsky’s with the medium or agency of language. We explore how metacognition and
self-regulation function within the realm of human behavior and development as described in the works of each of these theorists.
Key questions or issues that emerge for current research are outlined, and the limitations and benefits of each theorist’s
perspective vis-à-vis metacognition and self-regulation are discussed. 相似文献
1000.