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Pirkko Pietiläinen 《Information processing & management》1982,18(2):55-59
A method using the amount of semantic information of query terms as weight in a fuzzy relation of resemblance is presented. The relation can be used to partially order documents in decreasing order of resemblance with the query. Large operational bibliographic data bases are used to test the validity of the approach. 相似文献
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Research shows that formative assessment can exert a powerful effect on student learning, yet the complexity of formative assessment is not well understood and some curricular structures and practices do not fully exploit its potential. This article outlines the background to the political promotion of employability and shows that institutional responses are influenced by multiple considerations. It discusses formative assessment and models it as a complex signalling system before considering the implications, for students’ employability, of accentuating the attention given to formative assessment. The potential for action is discussed with reference to three levels: those of the institution, the department, and the individual academic. 相似文献
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Marco?A.?HaanEmail author S.?Gerhard?Dijkstra Peter?T.?Dijkstra 《Journal of Cultural Economics》2005,29(1):59-78
For centuries, there have been discussions as to whether only experts can judge the quality of cultural output, or whether the taste of the public also has merit. This paper tries to answer that question empirically, using national finals of the Eurovision Song Contest. We show that experts are better judges of quality in the sense that the outcome of finals judged by experts is less sensitive to factors unrelated to quality than the outcome of finals judged by public opinion. Yet, experts are not perfect; their judgment does still depend on such factors. This is also the case in the European finals of the contest. 相似文献
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Salmanzadeh A Kittur H Sano MB C Roberts P Schmelz EM Davalos RV 《Biomicrofluidics》2012,6(2):24104-2410413
Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool. 相似文献