全文获取类型
收费全文 | 76篇 |
免费 | 2篇 |
专业分类
教育 | 37篇 |
科学研究 | 8篇 |
体育 | 16篇 |
文化理论 | 1篇 |
信息传播 | 16篇 |
出版年
2022年 | 1篇 |
2019年 | 4篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 19篇 |
2012年 | 2篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2008年 | 3篇 |
2007年 | 3篇 |
2005年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 3篇 |
1999年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 5篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1964年 | 1篇 |
1872年 | 1篇 |
1871年 | 1篇 |
排序方式: 共有78条查询结果,搜索用时 0 毫秒
11.
12.
ABSTRACT Given the many changes in our students and their study and research practices, libraries are finding it necessary to seek new ways to reach these students. The Undergraduate Library at the University of Illinois at Urbana-Champaign created a new model to do so. Librarian's Office Hours are a hybrid of reference and instructional services that fulfill the dual purposes of meeting the needs of term paper research counseling and library workshops. This article discusses the strategies involved in the creation and implementation of this service and examines suggestions for the future of such a service. 相似文献
13.
Carole L. Hahn 《牛津教育评论》2013,39(1-2):231-250
This article reports on a comparative study of civic education in six countries-Britain, the USA, Germany, Denmark, the Netherlands and Australia. Differing policies and practices with respect to citizenship education among the six Western democracies were found to be associated with different patterns of adolescent student political attitudes and perceptions. In those contexts in which civic education includes political content and opportunities for students to explore and express opinions on public policy issues, and to engage in decision-making, young people (ages 15-19) appear to be more interested in the political arena than in those contexts in which they do not have such experiences. 相似文献
14.
Betzalel Avitzur Walter C. Hahn Samy Iscovici 《Journal of The Franklin Institute》1975,299(5):339-358
A variety of mathematical models may be used to analyse plastic deformation during a metal-forming process. One of these methods—limit analysis—places the estimate of required power between an upper bound and a lower bound. The upper and lower bound analyses are designed so that the actual power or forming stress requirement is less than that predicted by the upper bound and greater than that predicted by the lower bound. Finding a lower upper bound and a higher lower bound reduces the uncertainty of the actual power requirement. Upper and lower bounds will permit the determination of such quantities as required forces, limitations on the process, optimal die design, flow patterns, and prediction and prevention of defects.Fundamental to the development of both upper bound and lower bound solutions is the division of the body into zones. For each of the zones there is written either a velocity field (upper bound) or a stress field (lower bound). A better choice of zones and fields brings the calculated values closer to actual values.In the present work, both upper and lower bound solutions are presented for axisymmetric flow through conical converging dies. For the upper bound triangular velocity fields have been solved and compared to previously published work on spherical velocity fields. It is found that each type provides a lower solution over a part of the range of process variables. A previously published lower bound solution for axisymmetric flow is refined. 相似文献
15.
16.
17.
Corinne Hahn 《Educational Studies in Mathematics》1999,39(1-3):229-249
This article presents the results of a research study conducted with apprentices in order to examine the double hypothesis that vocational training incorporating work placement gives the opportunity to construct authentic situations out of the everyday practices of students and that these situations allow students to improve their understanding of mathematical problems. After analysis of workplace situations had shown that the only mathematical concept used by apprentices was that of proportionality applied to percentage calculations, we first analysed the way in which students at several levels handled this idea of percentage. We then devised an experimental framework in order to help the apprentices to transfer their knowledge. RéSUMé: Cet article présente les résultats d'une recherche menée avec des apprentis vendeurs afin de vérifier la double hypothèse qu'un enseignement professionnel en alternance donne l'opportunité de construire des situations authentiques, à partir des pratiques quotidiennes des élèves et que ces situations permettent aux élèves d'améliorer leur compréhension des problèmes mathématiques. L'analyse des situations de travail ayant montré que le seul concept mathématique dont les apprentis ont l'usage est le concept de proportionnalité appliqué aux calculs de pourcentage, nous avons d'abord analysé le comportement d'élèves de plusieurs niveaux face à cette notion de pourcentage. Nous avons ensuite mis en place un dispositif expérimental afin d'aider les apprentis à transférer leurs connaissances. This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
Infant Temperament: Stability by Age,Gender, Birth Order,Term Status,and Socioeconomic Status 下载免费PDF全文
Marc H. Bornstein Diane L. Putnick Maria A. Gartstein Chun‐Shin Hahn Nancy Auestad Deborah L. O'Connor 《Child development》2015,86(3):844-863
Two complementary studies focused on stability of infant temperament across the 1st year and considered infant age, gender, birth order, term status, and socioeconomic status (SES) as moderators. Study 1 consisted of 73 mothers of firstborn term girls and boys queried at 2, 5, and 13 months of age. Study 2 consisted of 335 mothers of infants of different gender, birth order, term status, and SES queried at 6 and 12 months. Consistent positive and negative affectivity factors emerged at all time points across both studies. Infant temperament proved stable and robust across gender, birth order, term status, and SES. Stability coefficients for temperament factors and scales were medium to large for shorter (< 9 months) interassessment intervals and small to medium for longer (> 10 months) intervals. 相似文献
19.
Quod MJ Martin DT Laursen PB Gardner AS Halson SL Marino FE Tate MP Mainwaring DE Gore CJ Hahn AG 《Journal of sports sciences》2008,26(14):1477-1487
The purpose of this study was to compare the effects of two practical precooling techniques (skin cooling vs. skin + core cooling) on cycling time trial performance in warm conditions. Six trained cyclists completed one maximal graded exercise test (VO2(peak) 71.4 +/- 3.2 ml x kg(-1) x min(-1)) and four approximately 40 min laboratory cycling time trials in a heat chamber (34.3 degrees C +/- 1.1 degrees C; 41.2% +/- 3.0% rh) using a fixed-power/variable-power format. Cyclists prepared for the time trial using three techniques administered in a randomised order prior to the warm-up: (1) no cooling (control), (2) cooling jacket for 40 min (jacket) or (3) 30-min water immersion followed by a cooling jacket application for 40 min (combined). Rectal temperature prior to the time trial was 37.8 degrees C +/- 0.1 degrees C in control, similar in jacket (37.8 degrees C +/- 0.3 degrees C) and lower in combined (37.1 degrees C +/- 0.2 degrees C, P < 0.01). Compared with the control trial, time trial performance was not different for jacket precooling (-16 +/- 36 s, -0.7%; P = 0.35) but was faster for combined precooling (-42 +/- 25 s, - .8%; P = 0.009). In conclusion, a practical combined precooling strategy that involves immersion in cool water followed by the use of a cooling jacket can produce decrease in rectal temperature that persist throughout a warm-up and improve laboratory cycling time trial performance in warm conditions. 相似文献
20.
Allen JR O'Keefe KB McCue TJ Borger JJ Hahn ME 《Sports biomechanics / International Society of Biomechanics in Sports》2008,7(1):38-53
Fly-fishing is a popular form of recreation. Recent evidence has associated overhand fly-casting movements with upper extremity pain. However, little research exists on the motions and coordination common to fly-casting. The aim of this study was to establish upper extremity kinematic trends of fly-casting while casting greater line lengths. It was hypothesized that kinematic casting parameters would increase and time between peak angular velocities would decrease with greater line length. Eighteen males participated in the study. Three-dimensional motion capture was conducted to calculate shoulder, elbow, and wrist kinematics during casting conditions of 6.1, 12.2, 18.3, and 24.4 m of line. Multiple analyses of variance were used to assess the condition effect of line length on the kinematic variables (P = 0.05). Overall, total range of movement increased with increasing length of line cast. Peak angular velocity exhibited a proximal-to-distal trend: peak shoulder internal rotation followed by elbow extension, then wrist ulnar deviation. Time between peak shoulder and elbow angular velocities increased significantly as line length increased. Our findings indicate that specific changes in total range of movement accommodate the demands of casting greater lengths of line. Also, joint velocity coordination patterns of fly-casting appear to follow a proximal-to-distal pattern. These findings represent an initial foundation for connections between kinematics and upper extremity pain reported by fly-fisherman. 相似文献