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排序方式: 共有2543条查询结果,搜索用时 234 毫秒
1.
Jee-Hyub Kim Byung-Kwan Kwak Seungwoo Lee Geunbae Lee Jong-Hyeok Lee 《Information Retrieval》2001,4(2):115-132
In Korean information retrieval, compound nouns play an important role in improving precision in search experiments. There are two major approaches to compound noun indexing in Korean: statistical and linguistic. Each method, however, has its own shortcomings, such as limitations when indexing diverse types of compound nouns, over-generation of compound nouns, and data sparseness in training. In this paper, we propose a corpus-based learning method, which can index diverse types of compound nouns using rules automatically extracted from a large corpus. The automatic learning method is more portable and requires less human effort, although it exhibits a performance level similar to the manual-linguistic approach. We also present a new filtering method to solve the problems of compound noun over-generation and data sparseness. 相似文献
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This paper examines the historical background of the development of special education and how “Learning in Regular Classrooms” (LRC) has become the major service delivery model to universalise compulsory education for children with disabilities in China. The authors assert that the current model of inclusive education in China was conceptualised through the influence of the Western ideology of inclusion and the practical consideration of Chinese socio-economical conditions. To realise this model, a number of strategies were introduced and widely practised in an attempt to effectively implement the LRC programs. Adverse social climate, the exam-oriented education system, and limited resources in all aspects, however, remained as critical elements to be overcome for the future development of inclusive education in China. The LRC model is expected to continue to be the main form of inclusive education in China. 相似文献
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活血皇浆对田径运动员血液动力流变学和血液有形成分参数的影响 总被引:2,自引:1,他引:1
根据中医内科辩证和因时制宜原则 ,对校田径代表队在夏季比赛期间服用活血皇浆前后进行血液动力流变学和血液有形成分参数的比较观察结果表明 ,运动员服液后在脉率 (PR)、每搏量 (SV)、心输出量 (CO)、左心有效泵力 (VPE)和左心能量有效利用率 (EWK )改善的同时 ,出现心肌耗氧量 (HOV)、心肌耗氧指数 (HOI)、心肌血液需要量 (CMBN)、心肌血液灌注量(CMBV)和总周阻 (TPR)、标准周阻 (SPR)、收缩压 (SP)舒张压 (DP)等参数下降 ,呈现机能和能量节省化 ,而血液状态则表现为血容量 (BV)增多 ,全血粘度 (η)和还原血粘度 (ηr)下降 ,切变应力增高 ,血流速度加快 ,有利于维持微循环正常功能。血液有形成分的改变提示 ,血红蛋白 (Hb)红细胞比积 (HCT)和血小板 (PL T)有增高趋势 ;平均红细胞血红蛋白浓度 (MCHC)下降 ,则有可能与 BV相对增多 ,红细胞 (RBC)体积增大有关 相似文献
7.
Gary Burnett Paul T. Jaeger Kim M. Thompson 《Library & information science research》2008,30(1):56-66
Information access is central to library and information science, yet explorations of its conceptual nature have been limited. Given the importance of information access to the discipline, there is a need for research to create a better understanding of the concept and its many roles in all activities and behaviors related to information. Drawing on the theoretical work of Elfreda Chatman, this article proposes that the study of information access can be facilitated through the recognition and examination of the physical, intellectual, and social aspects of information access. These types of access are examined through three case studies in terms of different information behaviors and contexts, with a particular focus on the importance of social access. The article also discusses the future roles that considerations of social access can play in research and theory. 相似文献
8.
In Information Retrieval, since it is hard to identify users’ information needs, many approaches have been tried to solve
this problem by expanding initial queries and reweighting the terms in the expanded queries using users’ relevance judgments.
Although relevance feedback is most effective when relevance information about retrieved documents is provided by users, it
is not always available. Another solution is to use correlated terms for query expansion. The main problem with this approach
is how to construct the term-term correlations that can be used effectively to improve retrieval performance. In this study,
we try to construct query concepts that denote users’ information needs from a document space, rather than to reformulate initial queries using the term correlations
and/or users’ relevance feedback. To form query concepts, we extract features from each document, and then cluster the features into primitive concepts that are then used to form
query concepts. Experiments are performed on the Associated Press (AP) dataset taken from the TREC collection. The experimental evaluation
shows that our proposed framework called QCM (Query Concept Method) outperforms baseline probabilistic retrieval model on
TREC retrieval. 相似文献
9.
This study examined two levels of media agenda effects on aggregatepublic opinion from different news sources. The effects wereinvestigated immediately and cumulatively. Content analysisdata from the 2000 U.S. presidential election coverage by fournational news organizations were related to the Gallup pre-electionpoll standings of each candidate. Regression analyses foundthat both the salience of a candidate and the salience of theattributes of a candidate cumulatively, but not immediately,influenced his standing in the polls. An analysis of news sourcessupported the finding that the two levels of agenda-settingeffects seemed mostly cumulative rather than immediate. Newsfrom different sources, however, tended to have effects of differentdegrees and sometimes different directions on candidate pollstandings. Cumulative effects of candidate salience on aggregateopinion change were found for non-partisan and neutral newssourcesreporters, poll reporting and public documentswhereasthe effects of candidate attribute salience mostly came frompartisan sourcesthe candidate himself and members ofthe competing political party. Possible political implicationsof these findings are discussed. 相似文献
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