Three dimensions of equity of access to higher education     

Tristan McCowan 《Compare》2016,46(4):645-665

Concerns over equity of access to higher education are widespread, but there is significant disagreement over what should constitute a fair system. This article assesses diverse conceptualisations of equity and explores the ways in which they embody themselves in the policies of three systems, those of England, Brazil and Kenya. While showing significant disparities of income level and enrolment ratio, all three have made concerted efforts to expand higher education access, accompanied by increasing stratification in terms of the quality and prestige of institutions. Analysis of policy options and outcomes leads to a proposal of three principles for understanding equity of access: availability, accessibility and horizontality. The third of these principles addresses the little-acknowledged safeguard that disadvantaged students should not be confined to lower-quality institutions, while at the same time allowing for diversity of ethos and disciplinary focus.  相似文献   

基于零点的逻辑函数bj图和dj图的转换     

黄瑞祥  孙浙永  肖林荣 《科技通报》2007,23(4):540-543,567

图形化简法是逻辑函数化简的有效工具。bi图和西图分别是RM展开式、CRM展开式的图珏表示。通过对RM展开式、CRM展开式系数关系的分析，提出了2种bj图和dj图的图形转换方法，并廷各种方法予以实例说明。对于5变量以下的逻辑函数，这二种方法具有简单、直观等特点。  相似文献   

Optimization of some factors affecting the performance of query expansion     

Young Mee Chung  Jae Yun Lee 《Information processing & management》2004,40(6):29

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   

基于动态演化博弈的企业技术创新均衡策略研究     

张倩 《科技管理研究》2016,(21)

企业技术创新是解决环境污染和经济增长矛盾的根本所在,成为实现环境保护和经济发展“双赢”的有效途径.政府环境规制、企业技术创新和公众环境参与是相互影响及制约的利益关系,因此,探究三方利益相关者对企业技术创新行为的影响成为学者研究的重要课题.从演化经济学的视角,运用动态演化博弈理论,构建政府、企业和公众的三方博弈模型,根据演化的仿生学研究,引入Lotka-Volterra模型求稳态均衡解,探究环境利益相关者的规制行为对企业技术创新策略的演化影响,并利用Matlab通过数值模拟进行检验.研究结果表明:环境规制与企业技术创新战略选择是一场混合战略均衡的博弈过程,企业、政府和公众的行为决策受其收益和成本的大小影响,利益相关方的环保措施在一定程度上会促进技术创新.因此,应恰当选择政府环境规制手段和强度水平,合理规划规制成本,不断提高公众环保意识,强化环境监管,促使企业以环保为己任,实施技术创新策略,减少环境污染.  相似文献   

基于代数分解的MSI组合电路扩展技术     

曹天汉 《科技通报》1996,12(5):279-284

讨论了一位全加器及优编器的逻辑功能，给出了适当的代数表示形式，在此基础上提出了基于代数分解方法的扩展技术。  相似文献   

Parsimonious translation models for information retrieval     

Seung-Hoon Na  In-Su KangJong-Hyeok Lee 《Information processing & management》2007

In the KL divergence framework, the extended language modeling approach has a critical problem of estimating a query model, which is the probabilistic model that encodes the user’s information need. For query expansion in initial retrieval, the translation model had been proposed to involve term co-occurrence statistics. However, the translation model was difficult to apply, because the term co-occurrence statistics must be constructed in the offline time. Especially in a large collection, constructing such a large matrix of term co-occurrences statistics prohibitively increases time and space complexity. In addition, reliable retrieval performance cannot be guaranteed because the translation model may comprise noisy non-topical terms in documents. To resolve these problems, this paper investigates an effective method to construct co-occurrence statistics and eliminate noisy terms by employing a parsimonious translation model. The parsimonious translation model is a compact version of a translation model that can reduce the number of terms containing non-zero probabilities by eliminating non-topical terms in documents. Through experimentation on seven different test collections, we show that the query model estimated from the parsimonious translation model significantly outperforms not only the baseline language modeling, but also the non-parsimonious models.  相似文献   

A review of ontology based query expansion     

J. Bhogal  A. Macfarlane  P. Smith 《Information processing & management》2007

This paper examines the meaning of context in relation to ontology based query expansion and contains a review of query expansion approaches. The various query expansion approaches include relevance feedback, corpus dependent knowledge models and corpus independent knowledge models. Case studies detailing query expansion using domain-specific and domain-independent ontologies are also included. The penultimate section attempts to synthesise the information obtained from the review and provide success factors in using an ontology for query expansion. Finally the area of further research in applying context from an ontology to query expansion within a newswire domain is described.  相似文献   

An empirical study of query expansion and cluster-based retrieval in language modeling approach     

Seung-Hoon Na  In-Su Kang  Ji-Eun Roh  Jong-Hyeok Lee 《Information processing & management》2007

The term mismatch problem in information retrieval is a critical problem, and several techniques have been developed, such as query expansion, cluster-based retrieval and dimensionality reduction to resolve this issue. Of these techniques, this paper performs an empirical study on query expansion and cluster-based retrieval. We examine the effect of using parsimony in query expansion and the effect of clustering algorithms in cluster-based retrieval. In addition, query expansion and cluster-based retrieval are compared, and their combinations are evaluated in terms of retrieval performance by performing experimentations on seven test collections of NTCIR and TREC.  相似文献   

顾客参与和服务创新关系研究:基于服务过程中知识转移的视角   总被引：7，自引：0，他引：7  

张若勇  刘新梅  张永胜 《科学学与科学技术管理》2007,28(10):92-97

顾客是服务企业重要的创新思想来源,顾客与企业之间的互动过程会影响到服务创新绩效。在服务交互的情景下,基于知识转移的视角,提出了顾客参与的三个维度如何影响顾客知识转移,并进一步影响服务创新绩效的研究框架,揭示了顾客参与服务过程与服务创新绩效的关系。  相似文献   

在线健康社区用户参与行为的影响因素研究综述   总被引：2，自引：0，他引：2  

张薇薇  蒋雪 《图书情报工作》2020,(4):136-145

[目的/意义]在线健康社区是健康问题关注者交流经验、知识和情感的重要平台,而用户参与是社区发展的关键。对用户参与行为的影响因素进行综合评述,可为这方面研究提供系统参考。[方法/过程]从信息生态系统的综合视角出发,分别从信息人、信息、信息技术和信息环境4个维度,系统评述用户参与行为影响因素和影响机理的主要成果和研究现状。[结果/结论]用户参与行为受到信息人、信息、信息技术和信息环境各维度的综合影响,相关成果比较丰富,已经形成较为成熟的研究主题。从社区类型、用户类型、持续参与等方面对未来研究趋势进行展望。  相似文献