全文获取类型
收费全文 | 173篇 |
免费 | 1篇 |
专业分类
教育 | 112篇 |
科学研究 | 26篇 |
各国文化 | 4篇 |
体育 | 21篇 |
文化理论 | 2篇 |
信息传播 | 9篇 |
出版年
2022年 | 3篇 |
2020年 | 3篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 8篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 29篇 |
2012年 | 10篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 4篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2002年 | 3篇 |
2000年 | 2篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1983年 | 3篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1969年 | 3篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 2篇 |
1965年 | 1篇 |
1963年 | 1篇 |
1962年 | 2篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1957年 | 2篇 |
1956年 | 5篇 |
1955年 | 2篇 |
1935年 | 1篇 |
1932年 | 1篇 |
1931年 | 1篇 |
1929年 | 1篇 |
1928年 | 1篇 |
1926年 | 2篇 |
1897年 | 2篇 |
1885年 | 1篇 |
1877年 | 1篇 |
1866年 | 1篇 |
1843年 | 1篇 |
排序方式: 共有174条查询结果,搜索用时 31 毫秒
81.
Development of a reciprocal multi-state shared resources network is described. The Basic Health Sciences Library Network (BHSL) is one the largest interlibrary loan networks free of direct charges to participants and any direct federal or state funding. Established in June 1986, BHSL started with 132 member libraries from three northeastern states. Current membership is 460 libraries in 10 states. Interlibrary loan activity for 1992 resulted in a collective cost savings of $592,672. This model of resource sharing can be applied to any group of libraries that access a common locator tool. 相似文献
82.
83.
Ian C. Kenny Eric S. Wallace Steve R. Otto 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):183-186
Abstract In this study we compared the kinematic features of the throwing motion between young baseball players of different age groups. Forty‐four Japanese baseball players aged 6.1 to 12.3 years who regularly played baseball, including pitchers and position players, had their throwing actions analyzed three‐dimensionally using high speed videography. Of this sample, 26 players aged above 9 years of age were categorized as the senior group, while the remaining 18 were categorized as the junior group. Senior group throwers had greater height and body mass, and produced a greater ball speed than junior group throwers. The throwing arm movement of senior group throwers was similar to that of adult skilled players. However, in the junior group throwers, the shoulder horizontal adduction angle was larger during the arm acceleration phase, and the maximum angular velocities of elbow extension and shoulder internal rotation occurred later than in senior group throwers. These results indicate that players aged above 9 years can acquire a mature throwing arm movement, while players younger than that will use an immature motion. A possible reason why these differences were shown is that the official baseball is relatively heavy for junior group throwers; they would be better advised to use a lighter ball in throwing practice. 相似文献
84.
The Nike Foundation, the philanthropic arm of Nike, Inc., seeks to prove the “The Girl Effect,” its theory of change, through investments in adolescent girls in the Global South. The foundation defines it as the “unique potential of 250 million adolescent girls to end poverty for themselves and the world.” This article examines the elaborate, yet continually contested processes of attempting to prove “The Girl Effect.” It draws on ethnographic research in the U.S. and Brazil (2009–2010) to analyze how the Nike Foundation funds, produces, and distributes knowledge on the purported potential of particular adolescent girls to end poverty. It focuses on how the monitoring and evaluation practices of one grantee in Brazil were informed by and contributed to the foundation's broader project of proving “The Girl Effect.” The analysis explains how this occurred through processes of knowledge production and educational intervention that were predicated on an epistemological understanding of the trope of “Third World girl.” It provides insights into how the foundation extends it power and authority over new bodies, institutions, and geographies by asserting itself as an expert on adolescent girls and by influencing the development agendas of more powerful global institutions. 相似文献
85.
Saskia Kistner Katrin Rakoczy Barbara Otto Charlotte Dignath-van Ewijk Gerhard Büttner Eckhard Klieme 《Metacognition and Learning》2010,5(2):157-171
An implication of the current research on self-regulation is to implement the promotion of self-regulated learning in schools.
Teachers can promote self-regulated learning either directly by teaching learning strategies or indirectly by arranging a
learning environment that enables students to practise self-regulation. This study investigates teachers’ direct and indirect
promotion of self-regulated learning and its relation to the development of students’ performance. Twenty German mathematics
teachers with their overall 538 students (grade 9) were videotaped for a three-lesson unit on the Pythagorean Theorem. Students’
mathematics performance was tested several times before and after the observed lessons. A low-inferent coding system was applied
to assess the teachers’ implicit or explicit instruction of cognitive strategies (e.g., organisation), metacognitive strategies
(e.g., planning), and motivational strategies (e.g., resource management). High-inferent ratings were used to assess features
of the learning environment that foster self-regulation. Results reveal that a great amount of strategy teaching takes place
in an implicit way, whereas explicit strategy teaching and supportive learning environment are rare. The instruction of organisation
strategies and some features of the learning environment (constructivism, transfer) relate positively to students’ performance
development. In contrast to implicit strategy instruction, explicit strategy instruction was associated with a gain in performance.
These results reveal a discrepancy between the usefulness of explicit strategy instruction and its rare occurrence in classrooms. 相似文献
86.
87.
88.
Previous studies have shown that the start plays a critical role in sliding events and explains more than 55% of the variance of the final time in luge. Experts evaluate the contribution of the arm strokes to be 23% of the total starting performance. The aim of the present study was to develop a measurement and feedback training tool (Speedpaddler) for the arm strokes of high-performance luge athletes. The construction is an aluminium alloy framework with a customary belt conveyor system, which is driven by two synchronized servo motors. Training is possible with constant speeds up to 12 m · s(-1) or several speed curves, which simulate the acceleration of different luge tracks. The construction facilitates variations in the inclination and speed of the conveyor belts and thereby the resistance and movement speed. If the athlete accelerates the conveyor belts during arm-paddling, the torque of the motors decreases. Torque measurements and high-speed video offer valuable insights into the several technique criteria. Comparisons of arm-paddle cycle durations on ice and on the Speedpaddler with 18 luge athletes (national team and juniors) showed no statistical differences. The Speedpaddler might be a useful tool to improve starting performance all year round. 相似文献
89.
Popadic Gacesa J Dragnic NR Prvulovic NM Barak OF Grujic N 《Journal of sports sciences》2011,29(6):635-641
The aim of this study was to determine whether triceps brachii muscle volume can be adequately estimated from a single anatomical cross-sectional area (ACSA) and can the same model be used for prediction after training. Thirty-five healthy male non-athletes (age 21.6 ± 2.5 years, body mass index 24.8 ± 3.5 kg · m(-2)) volunteered for this study. The volumes of the upper arm extensors were calculated from magnetic resonance imaging (MRI) sequence scans and regression models were developed, which were used to predict muscle volumes from single MRI cross-sectional scans taken at different points along the humerus length. The same procedure was repeated after 12 weeks of maximal resistance training of the elbow extensors. Correlation coefficients were calculated for Model A with CSA(max), humerus length (HL), and body mass index (r = 0.919), a model with CSA(50%) and HL (r = 0.922), and a model with CSA(60%) and HL (r = 0.920) (P < 0.001). The standard error of estimate for Model A, Model CSA(50%), and Model CSA(60%) was 8.0%, 7.7%, and 7.8% respectively. Thesame prediction formula can be used for the left arm (r = 0.904). If a single ACSA is used for triceps brachii volume prediction, the best fit is with Model CSA(60%) and HL, both before and after training (r = 0.941). By introducing humerus length into the calculation, we simplify the procedure for volume measurement, since it can be obtained during MRI scanning. 相似文献
90.
Otto Rauh 《Informatik - Forschung und Entwicklung》1997,12(3):117-127
Zusammenfassung. Redundante Komponenten in Entity-Relationship-Schemata führen zu Speicherverschwendung und Fehlern bei der Nutzung der aus
dem Schema gewonnenen Datenbanken. Zwischen Schemaredundanz und dem Konzept der ableitbaren Komponenten besteht eine enge
Verbindung, denn redundante Schemakomponenten sind stets ableitbar. Andererseits ist nicht jede ableitbare Komponente auch
redundant. Es wird deshalb zun?chst das Verh?ltnis zwischen redundanten und ableitbaren Komponenten diskutiert und eine Klassifizierung
eingeführt, welche die Modellierer bef?higt, entbehrliche von nicht entbehrlichen Komponenten zu unterscheiden. Eine spezielle
Art ableitbarer Komponenten, die Verkettung von Beziehungsarten, wird anschlie?end mit allen ihren Erscheinungsformen vorgestellt.
Au?erdem werden Methoden diskutiert, die helfen k?nnen, Verkettungen aufzudecken.
Eingegangen am 30. Mai 1996 / Angenommen am 8. April 1997 相似文献