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961.
Robert C. Berring 《Legal Reference Services Quarterly》2013,32(2):105-118
This is the third installment in Robert Berring's autobiography, The Education of a Twentieth Century Law Librarian. The first installment is at 32 Legal Reference Services Quarterly 1 (2013). The end of the traditional world of law libraries is chronicled through a study of the workings of the Harvard Law Library in the period 1978-1981. Computerized catalogs, changing styles of reference and difficult questions of management are explored. The painful transition that faced all libraries is discussed. This is the third installment of a five part series on the profound change in law libraries during this period. 相似文献
962.
963.
关联规则挖掘是解决电子商务推荐问题的重要方法之一.针对传统关联规则挖掘算法在解决移动电子商务环境个性化推荐问题时反复扫描数据库,频繁项挖掘效率低,关联规则挖掘准确率低以及规则大量冗余等不足,提出一个基于事务矩阵和用户兴趣度的关联规则挖掘算法(Matrix-and-Interestingness-based Association Rules Mining,MIbARM).该算法仅需扫描一次数据库,并在挖掘过程中不断缩小算法搜索空间以避免生成冗余候选项,同时避免了冗余规则挖掘,从而提高了挖掘效率.最后,在四组人工数据和160种参数组合的数值实验环境下,引入Apriori、CBAR 及BitTableFI算法对MIbARM进行对比验证.结果表明,在不减少有趣规则的前提下,MIbARM不但可有效避免冗余候选项集的产生,而且大幅减少了冗余规则数量,极大提高了算法的搜索效率,同时提升了个性化推荐的质量,更适用于移动电子商务环境下的个性化推荐问题. 相似文献
964.
V. B. Saputra S. K. Ong A. Y. C. Nee 《上海大学学报(英文版)》2014,(3):222-230
This paper presents a calibration method for parallel manipulators using a measurement system specially installed on an external fixed frame. The external fixed frame is important as an error reference for calibration in certain operations, such as in the configuration of a parallel manip- ulator functioning as a machine tool where the workpiece is fixed to a worktable. The pose of the end-effector is mea- sured using three digital indicators installed on the external fixed frame. To enable measurement, the end-effector is assumed to be a plane large enough that all digital indicators could touch. The error is defined as the difference between the theoretical and actual readings of the digital indicators. The geometric parameters of the parallel manipulator are optimized to minimize this error. This calibration method is low cost and feasible for compensating geometric parameter errors for a parallel manipulator. Optimal pose selection for the calibration is achieved using a swarm intelligence search algorithm. The method is implemented on a prototype of a six degrees-of-freedom (DOFs) Gough-Stewart platform constructed to function as a machine tool. 相似文献
965.
Effective teachers are often creative ones, yet an examination of creative teaching is largely invisible in the North American creativity literature. Even within education there is little about teachers’ own creative practice. Nonetheless, there are benefits to studying creative teachers: in education it can explicate ways of enhancing teachers’ creativity and enriching praxis; and in psychology it can extend our understanding of social and interpersonal creativity, as well as everyday creativity. This paper reviews 12 Canadian case studies of creative teaching conducted by a creative teaching research group. An in-depth elaboration of two themes, creative person and community, is presented. 相似文献
966.
Meaghan C. Guiney Jamie Zibulsky 《Journal of educational and psychological consultation》2017,27(1):52-71
ABSTRACTUsing samples of novice and advanced consultants in training (CITs), this study explored the development of consultation self-efficacy (CSE) for both process-oriented and problem-oriented aspects of consultation. Regardless of experience level, self-efficacy in both domains increased with training. However, significantly greater gains were made by novice CITs as compared to their advanced counterparts. In addition, feedback collected from consultees was generally favorable, and consultants received high ratings on items that reflected both process- and problem-focused skills. Implications for consultation training are discussed. 相似文献
967.
Homework: a cross-cultural examination 总被引:5,自引:1,他引:5
Cultural differences in the amount of time spent on homework and in beliefs and attitudes about homework were investigated through interviews with more than 3,500 elementary school children, their mothers, and their teachers. The children lived in 5 cities: Beijing, Chicago, Minneapolis, Sendai (Japan), and Taipei. Chinese children were assigned more homework and spent more time on homework than Japanese children, who in turn were assigned more and spent more time on homework than American children. Chinese children also received more help from family members with their homework than American and Japanese children. Chinese children were found to have more positive attitudes about homework than American children; Japanese children's attitudes were between those of the Chinese and American children. Relations between amount of time spent on homework by children, amount of time parents spent assisting their children with homework, and children's achievement were also explored. The views of both parents and teachers about the value of homework are discussed. 相似文献
968.
Eric C. Haakonssen Martin Barras Louise M. Burke David G. Jenkins David T. Martin 《European Journal of Sport Science》2016,16(6):645-653
The aims of this study were to describe normative values and seasonal variation of body composition in female cyclists comparing female road and track endurance cyclists, and to validate the use of anthropometry to monitor lean mass changes. Anthropometric profiles (seven site skinfolds) were measured over 16 years from 126 female cyclists. Lean mass index (LMI) was calculated as body weight?×?skinfolds?x. The exponent (x) was calculated as the slope of the natural logarithm of body weight and skinfolds. Percentage changes in LMI were compared to lean mass changes measured using dual-energy X-ray absorptiometry (DXA) in a subset of 25 road cyclists. Compared to sub-elite and elite cyclists, world class cyclists were (mean [95% CI]) 1.18?kg [0.46, 1.90] and 0.60?kg [0.05, 1.15] lighter and had skinfolds that were 7.4?mm [3.8, 11.0] and 4.6?mm [1.8, 7.4] lower, respectively. Body weight (0.41?kg [0.04, 0.77]) and skinfolds (4.0?mm [2.1, 6.0]) were higher in the off-season compared to the early-season. World class female road cyclists had lower body weight (6.04?kg [2.73, 9.35]) and skinfolds (11.5?mm [1.1, 21.9]) than track endurance cyclists. LMI (mean exponent 0.15 [0.13, 0.18]) explained 87% of the variance in DXA lean mass. In conclusion, higher performing female cyclists were lighter and leaner than their less successful peers, road cyclists were lighter and leaner than track endurance cyclists, and weight and skinfolds were lowest early in the season. LMI appears to be a reasonably valid tool for monitoring lean mass changes. 相似文献
969.
Serum glycoproteins were evaluated in oral squamous cell carcinoma patients treated with radiotherapy and also the effect
of vitamin E was studied. Cell surface glycoconjugates are important parameters in the detection of malignancy. Thus, the
objective of the present study is to evaluate the efficacy of vitamin E on glycoproteins in oral cavity cancer patients treated
with radiotherapy. The study includes 26 age and sex matched normal healthy individuals and 26 patients with squamous cell
carcinoma of oral cavity. These patients were divided into two groups, one for radiotherapy alone (at a dosage of 6000 cGy
in five fractions per week for a period of six weeks) and the other for radiotherapy plus vitamin E supplementation (at a
dosage of 400 IU / day of vitamin E) for the entire period of radiotherapy. Levels of hexose, hexosamine, fucose and sialic
acid were increased in oral squamous cell carcinoma patients and a significant decrease was observed in radiation treated
patients when compared to control. The levels of glycoconjugates were significantly decreased in radiation treated patients
supplemented with vitamin E. This measurement may be useful in assessing disease progression and identifying patients resistant
to therapy and a possible role of vitamin E on reduction in glycoconjugate levels of radiation treated oral squamous cell
carcinoma patients. 相似文献
970.
Investigations employing primates have sometimes used tests of concurrent object-discrimination as indexes of multiproblem memory in comparative studies of neuropathological impairment. The present investigation was an attempt to employ a comparable test procedure with rats. Data from two experiments indicated that rats could indeed be trained on a concurrent object-discrimination task. Furthermore, results from the second experiment indicated that these performances and brightness discriminations shared the property of disruption by posterior decortication. Implications for the neuropsychology of learning and memory are discussed. 相似文献