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121.
美国远程教育的新探索——西部州长大学的办学理念与实践 总被引:3,自引:0,他引:3
钱玲 《中国远程教育(综合版)》2006,27(3):72-75
西部州长大学作为美国远程教育领域具有特色的虚拟大学,因其办学的灵活性和创新性,创办9年来一直受到美国远程教育领域的关注。本文在简要介绍其办学动因和发展现状后,分析其办学的特色,以期对我国远程教育的发展有所借鉴。 相似文献
122.
提出了一个基于J2EE平台的企业MIS的设计模型,阐述了系统基于J2EE平台的架构和各个部分所应用的技术,包括多层体系结构、EJB、JSP及Servlet多项技术,其中重点介绍了EJB的设计,并结合作者开发此系统的实践,总结了其中的经验和教训. 相似文献
123.
边玲 《天津职业院校联合学报》2004,6(1):16-18
教师队伍建设是学校基本建设的主要任务之一,是校长的重要职责。学校应以调整为契机,积极稳妥地充实教师队伍;制定相关政策,支持教师进修学习;以科研为先导,提高教师的科研能力与水平;加强教学评估督导,促进教师提高教育教学质量;以现代信息技术为重点,加强教师队伍的全员培训。 相似文献
124.
Parallel machine scheduling problems, which are important discrete optimization problems, may occur in many applications. For example, load balancing in network communication channel assignment, parallel processing in large-size computing, task arrangement in flexible manufacturing systems, etc., are multiprocessor scheduling problem. In the traditional parallel machine scheduling problems, it is assumed that the problems are considered in offline or online environment. But in practice, problems are often not really offline or online but somehow in-between. This means that, with respect to the online problem, some further information about the tasks is available, which allows the improvement of the performance of the best possible algorithms. Problems of this class are called semi-online ones. In this paper, the semi-online problem P2|decr|lp (p>1) is considered where jobs come in non-increasing order of their processing times and the objective is to minimize the sum of the lp norm of every machine's load. It is shown that LS algorithm is optimal for any lp norm, which extends the results known in the literature. Furthermore, randomized lower bounds for the problems P2|online|lp and P2|decr|lp are presented. 相似文献
125.
126.
The purpose of the current study was to investigate a two-stage model in which parent-related stress and hopelessness each served as mediators of the relationship between perceived parental bonding and South Korean adolescent peer victimization. This study also examined whether the mediating relationships differed by the gender of parents and adolescents. A casual chain with three links and four sets of variables were analyzed using structural equation modeling. Data were collected from 800 adolescents attending 10 middle schools in the Busan region of South Korea. Results indicated that both maternal and paternal parental bonding were negatively associated with stress, stress was positively associated with hopelessness, and hopelessness was positively associated with South Korean adolescent peer victimization. Most importantly, the significant negative associations between both maternal and paternal parental bonding and peer victimization were mediated by both stress and hopelessness. Furthermore, gender differences in these relationships existed for both parents and adolescents. Limitations and implications to practice were discussed. 相似文献
127.
淮阴侯韩信的悲剧令千古叹惋,论述其成因可谓代有异说。然而,当我们对这一悲剧重新予以认识时发现,构成韩信悲剧的要素是多方面的,有封建制度的残酷和封建统治人才观的狭隘,也有其自身的人格缺憾。 相似文献
128.
129.
Word sense disambiguation (WSD) is meant to assign the most appropriate sense to a polysemous word according to its context. We present a method for automatic WSD using only two resources: a raw text corpus and a machine-readable dictionary (MRD). The system learns the similarity matrix between word pairs from the unlabeled corpus, and it uses the vector representations of sense definitions from MRD, which are derived based on the similarity matrix. In order to disambiguate all occurrences of polysemous words in a sentence, the system separately constructs the acyclic weighted digraph (AWD) for every occurrence of polysemous words in a sentence. The AWD is structured based on consideration of the senses of context words which occur with a target word in a sentence. After building the AWD per each polysemous word, we can search the optimal path of the AWD using the Viterbi algorithm. We assign the most appropriate sense to the target word in sentences with the sense on the optimal path in the AWD. By experiments, our system shows 76.4% accuracy for the semantically ambiguous Korean words. 相似文献
130.
This paper examines the factors affecting the performance of global query expansion based on term co-occurrence data and suggests a way to maximize the retrieval effectiveness. Major parameters to be optimized through experiments are term similarity measure and the weighting scheme of additional terms. The evaluation of four similarity measures tested in query expansion reveal that mutual information and Yule's Y, which emphasize low frequency terms, achieve better performance than cosine and Jaccard coefficients that have the reverse tendency. In the evaluation of three weighting schemes, similarity weight performs well only with short queries, whereas fixed weights of approximately 0.5 and similarity rank weights were effective with queries of any length. Furthermore, the optimal similarity rank weight achieving the best overall performance seems to be the least affected by test collections and the number of additional terms. For the efficiency of retrieval, the number of additional terms needs not exceed 70 in our test collections, but the optimal number may vary according to the characteristics of the similarity measure employed. 相似文献