影子教育提升了学业成绩吗?——来自CEPS的经验证据

本文利用中国教育追踪调查(CEPS2013)数据,运用倾向性得分匹配法(PSM),分析影子教育对学生学业成绩的影响,并基于影子教育参与时间选择异质性视角,构建中介效应模型,进一步考察了影子教育影响学生学业成绩的可能路径.研究表明:(1)总体上看,影子教育能够提高学生学业成绩,而且这种效应在优势学生群体(非流动学生、非留守学生和家庭经济条件较好的学生)中更明显.(2)周一到周五参与影子教育将显著降低学生学业成绩;周末参与影子教育将显著提高学生成绩,并且学生学业成绩与参与时间经历了一个“先上升再下降”的“倒U型”,当参与时间为4.45小时时,学生学业成绩提升程度最高.(3)在周一到周五,参与影子教育通过挤占休闲时间降低了学生的学业成绩;在周末,参与影子教育通过挤出娱乐时间提升了学生的学业成绩.     

T(1,2,n)∪(s∪i=0 CPi)及补图的匹配唯一性

本文研究了图的匹配唯一性，给出了T（1，2，n）∪（S∪i=0CPi）及补图匹配唯一的充要条件．     

A natural language user interface for fuzzy scope queries

This paper presents a two-agent framework to build a natural language query interface for IC information system, focusing more on scope queries in a single English sentence. The first agent, parsing agent, syntactically processes and semantically interprets natural language sentence to construct a fuzzy structured query language (SQL) statement. The second agent, defuzzifying agent, defuzzifies the imprecise part of the fuzzy SQL statement into its equivalent executable precise SQL statement based on fuzzy rules. The first agent can also actively ask the user some necessary questions when it manages to disambiguate the vague retrieval requirements. The adaptive defuzzification approach employed in the defuzzifying agent is discussed in detail. A prototype interface has been implemented to demonstrate the effectiveness. Project (No. 98-15) supported by the National Planning Committee of China     

国企改革的三分法及其前景

本文从国有企业本身的特点(内因)出发,把国企分为三类,不同类型的国企用不同的产权制度(外因)去对症下药,于是引出国企改革的三分法。同时借鉴国外国有经济行业分布,认为我国国有经济应实行有针对性的战略收缩,把国有经济从量的扩张转移到质的提高上来。     

Matching messages to the values underlying value-expressive and social-adjustive attitudes: reconciling an old theory with a contemporary measurement approach

Functional theory defines value-expressive attitudes as attitudes that are formed to aid in the achievement of one's values, and social-adjustive attitudes as attitudes that are formed from the desire to affiliate with others. The current investigation argues that both functions are based in a person's values, with the social-adjustive function being a specific form of a value-expressive attitude. Contemporary approaches to this theory have argued that these attitude functions can be inferred from scores on the self-monitoring scale, thus eliminating the need to measure the values underlying these functions. The current investigation argues that the success of studies using the self-monitoring scale to infer these functions should be due to the covariance of the other-directedness dimension of the scale with the values underlying those attitudes. Overall, the findings of the investigation indicate that the formation of these functional attitudes depends more on the match between the value-content of the persuasive messages and the extent to which the message recipients hold those values than their level of other-directedness. Other-directedness did not covary with the values that underlie value-expressive and social-adjustive attitudes, but did aid in the reception of the social-adjustive message. Thus, the research using the self-monitoring scale to infer functions cannot be fully reconciled with the conceptualizations of value-expressive and social-adjustive attitudes.     

基于神经网络的炸药与岩石匹配的研究

文章基于MATLAB神经网络工具箱平台,利用BP神经网络建立炸药岩石匹配模型,并根据工程实践中收集的数据和文献中的经典数据作为网络模型的学习训练和检验样本,从岩石爆破特性和爆破效果等因素出发来预测炸药爆炸特性和爆破设计参数,并结合某工程实例数据为输入值对模型进行检验,得到输出值预测误差均在10%以下,仿真效果较好。证明本模型对工程爆破实践有一定的指导意义和参考价值,并为炸药岩石匹配问题的研究提供了较好的思路。     

基于二分图匹配的一类多机调度问题研究

二分图是图论当中一种特殊的模型,求带权二分图的最佳匹配算法对许多具有最优解的实际应用问题的解决是准确和高效的。针对多机系统的操作系统的一类多机调度问题进行了分析,建立了该问题的二分图模型并给出了二分图匹配的算法,对所给算法的复杂度进行了分析和讨论。实验结果验证了所提出方法的有效性。     

A novel model for extending international co-operation in science and education

In September 1994 the University of Twente, the Netherlands, and Zhejiang University, China, decided to cooperate in the field of science, education and management. After several visits of delegations from both sides it was considered worthwhile to explore further opportunities for mutual cooperation. The directors of international cooperation on each side jointly commissioned a project to investigate the potential in a systematic way and to establish further contacts where appropriate. This paper reports on the results of the research cum matching project.To reveal promising matches between multiple departments of both academic institutions a matching model for universities was designed. The study was carried out along two parallel lines. In the research line the theoretical framework was developed into a model for international university co-operation. Moreover, an analysis was carried out on internal, external and cultural aspects resulting in a set of thirty four influencing factors.In the matching line a total of seventy interviews were held in order to identify promising matches between units at both universities. This line resulted in eleven promising matches for further co-operation.The novel model appeared useful in analyzing the variety of factors and in developing matches between both universities. In the further implementation of the model the issues of "level of co-operation" and "top-down versus bottom-up" need to be addressed in more detail.     

I形图的匹配唯一性

证明了In匹配唯一当且仅当n=7或n≥8为偶数。     

课堂多媒体演示课件色彩的选择与应用

该文结合色彩心理学和环境心理学理论,分析讨论了课堂多媒体演示课件色彩的选择与应用问题。