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排序方式: 共有206条查询结果,搜索用时 343 毫秒
101.
In recent years, firms have increasingly contributed to and been confronted with a patent landscape characterized by numerous but marginal inventions, overlapping claims and patent fences. As a result, firms risk their patent applications to be pre-empted or to be infringed upon by rivals. While both aspects constitute major challenges for the appropriation of returns to inventive activity, extant literature suggests that participation in the market for technology might actually resolve or at least alleviate these problems. In this paper, we investigate the effect of pre-empted and infringed patents on firms’ engagement in in- and cross-licensing. Based on a sample of more than 1100 German manufacturing firms our results show that firms engage in in-licensing as a reaction to pre-empted patents and in cross-licensing if their protected IP was infringed upon. However, these effects vary depending on the fragmentation of technology fields and whether the firm operates in a discrete or complex product industry. 相似文献
102.
This study focused on differences between teacher‐centred and learner‐centred experiments in soil ecology. After a pilot study, we selected three experiments simple enough to be carried out by pupils even with little experience in self‐determined learning and hands‐on practice. The sample comprised 123 fifth and sixth graders from a middle school (four classes). We found a significant influence of treatment on achievement and pupils enrolled in a learner‐centred environment scored higher. Girls scored higher than boys in both treatments. We found no differences in well‐being, boredom or difficulty of the tasks, but pupils of the learner‐centred group expressed a higher interest. 相似文献
103.
104.
Franziska Etter Arkadiusz Bukowski Christoph Alexander Rüst Thomas Rosemann Romuald Lepers 《Journal of sports sciences》2013,31(9):996-1006
Abstract This study investigated the participation and performance trends as well as the age and gender interaction at the Olympic distance ‘Zürich Triathlon’ (1.5?km swim, 40?km cycle and 10?km run) from 2000 to 2010 in 7,939 total finishers (1,666 females and 6,273 males). Female triathletes aged from 40 to 54 years significantly (P?<?0.05) increased their participation while the participation of younger females and males remained stable. Males of 50–54 years of age and females of 45–49 years of age improved their total race time. For elite top five overall triathletes, mean gender differences in swimming, cycling, running and overall race time were 15.2?±?4.6%, 13.4?±?2.3%, 17.1?±?2.5%, and 14.8?±?1.8%, respectively. For both elite and age group athletes, the gender difference in cycling time was significantly (P?<0.001) lower than for swimming and running. The gender difference in overall Olympic distance triathlon performance increased after the age of 35 years, which appeared earlier compared to long distance triathlon as suggested by previous studies. Future investigations should compare gender difference in performance for different endurance events across age to confirm a possible effect of exercise duration on gender difference with advancing age. 相似文献
105.
Research in Science Education - Science explanation videos, especially online ones, have become popular. They cover nearly all topics from school science curricula. Teachers use them in a flipped... 相似文献
106.
Bruno della Chiesa Vanessa Christoph and Christina Hinton 《Mind, Brain, and Education》2009,3(1):17-26
ABSTRACT— The Organization for Economic Cooperation and Development's (OECD) Center for Educational Research and Innovation (CERI) carried out the Learning Sciences and Brain Research project (1999–2007) to investigate how neuroscience research can inform education policy and practice. This transdisciplinary project brought many challenges. Within the political community, participation in the project varied, with some countries resisting approval of the project altogether, in the beginning. In the neuroscientific community, participants struggled to represent their knowledge in a way that would be meaningful and relevant to educators. Within the educational community, response to the project varied, with many educational researchers resisting it for fear that neuroscience research might make their work obsolete. Achieving dialogue among these communities was even more challenging. One clear obstacle was that participants had difficulty recognizing tacit knowledge in their own field and making this knowledge explicit for partners in other fields. This article analyzes these challenges through a knowledge management framework. 相似文献
107.
The revenue composition of for-profit and non-profit organisations is fundamentally different. Non-profit organisations have diversified revenues and must therefore manage an income portfolio. For the management of the income portfolio of a non-profit sport club it is not only important that sufficient revenues are available, but also where they come from as complex interactions exist among different revenue sources. These interactions are referred to as crowd-out effects (increases in one revenue source lead to decreases in another source) and crowd-in effects, respectively. The interactions among revenue categories of non-profit sport clubs were analysed using a longitudinal dataset from a nationwide sport club survey in Germany (n = 5026). Elasticity measures were calculated within a regression framework which provided information about the nature and significance of interactions. The results revealed a significant positive interaction between revenues from donations and sport supply (e.g., membership and service fees) pointing towards a crowd-in effect, i.e., increased revenues from donations have crowded in revenues from sport supply. Moreover, increased revenues from subsidies were found to crowd in revenues from donations and economic activities (e.g., sponsorship). Significant negative interactions were observed for revenues from economic activities and other supply suggesting that increased revenues from economic activities have crowded out revenues from other supply. The findings indicated an increased level of commercialisation supporting a modernisation of German clubs. Furthermore, the uncertainties have increased and therefore sport clubs have to consider the level of uncertainty of their revenue sources when they manage their income portfolio. 相似文献
108.
Christoph Gollmick und Uta St?rl 《Informatik - Forschung und Entwicklung》2002,17(4):157-166
Zusammenfassung. Die st?ndig wachsende Menge der in Datenbanksystemen verwalteten Daten und steigende Verfügbarkeitsanforderungen verlangen
die Entwicklung immer schnellerer und effizienterer Backup- und Re-covery-Verfahren. Die Ausnutzung von Parallelit?t beim
Backup und Restore ist dabei einer von verschiedenen “intelligenten” L?sungsans?tzen, die nicht allein auf schnellere Hardware
setzen, sondern helfen, eine bestehende Infrastruktur optimal auszunutzen. Der Beitrag stellt ein Puffer-Proze?-Modell vor,
mit dessen Hilfe parallele Backup- und Restore-Algorithmen systematisch abgeleitet werden k?nnen. Eine definierte Auswahl
von Algorithmen wird anhand praxisbezogener Kriterien bewertet und klassifiziert (inklusive Einordnung der wichtigsten DBMS-Produkte).
Me?ergebnisse prototypisch implementierter Algorithmen schlie?lich belegen die Anwendbarkeit des Puffer-Proze?-Modells zur
Implementierung effizienter paralleler Backup- und Restore-Algorithmen.
Eingegangen am 31. Januar 2002 / Angenommen am 5. Juli 2002 相似文献
109.
An analytical framework for the cross-country comparison of higher education governance 总被引:2,自引:0,他引:2
In this article we provide an integrated framework for the analysis of higher education governance which allows us to more systematically trace the changes that European higher education systems are currently undergoing. We argue that, despite highly insightful previous analyses, there is a need for more specific empirically observable indicators of policy change and inertia. We therefore propose a systematic classification of empirical indicators of higher education governance. To do so, we look at three historically entrenched and still highly relevant European models of higher education??academic self-governance, the state-centered model and the market-oriented model. Based on these broader overarching models which reflect the tensions between the state, market and academia, we develop three ideal-types that take internal university governance as well as the role of the state and external stakeholders into account. Against this background, we derive empirical indicators with regard to the institutional balance of power, financial governance, personnel autonomy and substantive matters. Our analytical contribution shall enable scholars, and in particular political and social scientists, to trace ongoing patterns of change and convergence as well as persistence and inertia in higher education governance arrangements. 相似文献
110.