优化问题的新步长法则     

吴庆军  韦增欣 《上海大学学报(英文版)》2007,11(2):135-141

The step-size procedure is very important for solving optimization problems. The Armijo step-size rule, the Armijo-Goldstein step-size rule and the Wolfe-Powell step-size rule are three well-known line search methods. On the basis of the above three types of line search methods and the idea of the proximal point methods, a new class of step-size rules was proposed. Instead of a single objective function f, f ＋1/2（x - xk）^TBk（x-Xk） was used as the merit function in iteration k, where Sk is a given symmetric positive definite matrix. The existence of the steplength for the new rules was proved. Some convergence properties were also discussed.  相似文献   

我国二手车市场目前存在的问题及发展方向   总被引：2，自引：0，他引：2  

陈超 《邢台职业技术学院学报》2005,22(5):32-33

随着我国汽车产销量的迅速增长,汽车保有量也越来越多,这就为二手车市场的发展带来了广阔的前景.本文主要讲述了目前我国二手车市场存在的问题,以及要解决目前二手车市场问题的具体措施.  相似文献   

构建大学生心理健康教育综合工作体系的实践和探索   总被引：3，自引：0，他引：3  

陈先建 《广西教育学院学报》2005,(3):47-49

高校大学生心理健康教育综合工作体系是根据大学生的心理发展特点，运用心理学的理论和技巧，结合学校及社会资源，开展学生心理健康教育、心理咨询以及心理危机干预工作的系统。本通过对温州医学院心理健康教育工作体系的个案剖析，提出了构建高校大学生心理健康教育综合工作体系应该确立多元参与的思想观念，体现三级功能确保教育的有效性，在实施心理健康教育中要坚持主体性原则、协同性原则、科学性与实效性统一的原则。  相似文献   

Super-proximity routing in structured peer-to-peer overlay networks     

吴增德  饶卫雄  马范援 《浙江大学学报(A卷英文版)》2004,5(1):16-21

Peer-to-Peer systems are emerging as one of the most popular Internet applications. Structured Peer-to-Peer overlay networks use identifier based routing algorithms to allow robustness, load balancing, and distributed lookup needed in this environment. However, identifier based routing that is independent of Internet topology tends to be of low efficiency. Aimed at improving the routing efficiency, the super-proximity routing algorithms presented in this paper combine Internet topology and overlay routing table in choosing the next hop. Experimental results showed that the algorithms greatly improve the efficiency of Peer-to-Peer routing.  相似文献   

The inquiry learning forum:     

Julie Moore  Sasha Barab 《TechTrends》2002,46(3):44-49

  相似文献   

化学农药对稻田昆虫群落组成及其动态的影响     

颜忠诚  陈常铭 《湘潭师范学院学报(社会科学版)》1989,(6)

本文对不同用药水平处理下的稻田昆虫群落及其动态的变化情况进行了研究。 1、稻田昆虫群落物种丰富度,在时间序列变化中,天敌种类数多于害虫类;在用药处理田,害虫和天敌种类数低于未用药田。经存在度分析,稻田共有27种以上的常见种,其中害虫10种,捕食性天敌昆虫5种,寄生性天敌昆虫6种。稻田蜘蛛6种。 2、优势度在用药处理下均趋降低,但降低水平不一致,害虫类优势度降低值比天敌类降低值高,而在叶面活动的天敌优势度降低明显。  相似文献   

Forming shared inquiry structures to support knowledge building in a grade 5 community     

Dan Tao  Jianwei Zhang 《Instructional Science》2018,46(4):563-592

This study explores the reflective processes by which a grade 5 science community co-constructed shared inquiry structures to focus and guide its inquiry about human body systems over a school year supported by a collaborative online environment. The co-constructed structures included a list of collective wondering areas as the shared focus of inquiry and models of the inquiry process in the form of “research cycle.” Qualitative analyses of field notes, classroom videos, student notebooks and interviews elaborate the evolution of the inquiry areas and the “research cycle” model as well as students’ adaptive use of the structures to guide deeper inquiry. Content analyses of students’ individual research questions and collaborative online discourse indicate that students used the structures to develop more advanced inquiry and make productive contributions. The results contribute to elaborating a reflective structuration approach to co-organizing and sustaining long-term, open-ended inquiry in knowledge building communities.  相似文献   

A technological pedagogical content knowledge based instructional design model: a third version implementation study in a technology integration course     

Chia-Jung Lee  ChanMin Kim 《Educational technology research and development : ETR & D》2017,65(6):1627-1654

This paper presents the third version of a technological pedagogical content knowledge (TPACK) based instructional design model that incorporates the distinctive, transformative, and integrative views of TPACK into a comprehensive actionable framework. Strategies of relating TPACK domains to real-life learning experiences, role-playing, and teachers as designers were developed based on the three views and integrated into the third version of the model. The model was then applied in a teacher education undergraduate course on technology integration. A case study approach was used. Data were collected from the participants’ discussion worksheets, lesson designs, and the researchers’ field observation notes. Data analysis results suggest that the strategies integrated into the model helped the participants deepen their understanding of student-centered technology applications and practice TPACK. Findings, implications, and future research possibilities are discussed.  相似文献   

杜威经验教育观之实践蕴涵 ——《民主主义与教育》解读     

陈秀兰 《高教发展与评估》2007,23(3):78-83

"经验"是杜威论著<民主主义与教育>的核心范畴与逻辑起点.他赋予"经验"以实践意蕴,认为经验是行为与结果的结合、主体与环境的互动;他将教育哲学、教育功能、教育目的定位于"经验",认为教育即"经验的改造";他视课程与教学为改组、改造"经验"的重要载体和基本途径,这对当下讨论教育回归"生活世界"有一定启示作用.  相似文献   

Career guidance in India based on O*NET and cultural variables     

Mohit Bhatnagar 《International Journal for Educational and Vocational Guidance》2018,18(1):81-99

The Occupational Information Network (O*NET) is the primary source of occupational information in the United States (US). In this study, I review O*NET’s usage for career guidance in India and conceive a career intervention based on it. In an empirical evaluation adopting a posttest-only experimental design with post-graduate management students (N = 220), effectiveness of the career intervention in reducing career decision-making difficulties is presented. An important cultural insight the study offers regarding occurrence of career decision-making difficulties, are the differences due to vertical–horizontal characteristics, apart from the more researched individualism–collectivism characteristics.  相似文献