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961.
The aim of the present study was to investigate the effects of war environment on political attitudes toward an enemy and on personality development. High school students from an Israeli town on the border of “Fatahland” and a town in central Israel were asked to fill out: A questionnaire on their political views toward the Israel-Arab conflict and the Repression-Sensitization (R-S) scale (Byrne et al., 1963). Results showed three factors in the students' political views: (a) Return of the Controversial Territories (Samaria, Judea, Gaza Strip, Golan Heights and Sinai); (bj Credibility of the Arabs in negotiation; (c) The policy of the previous government in its return of certain territories in Sinai.It was found that the students in the border town were less opposed to return the Controversial Territories than the students in the non-border town. Repressers in both towns gave more credibility to the Arabs in negotiation than did sensitizers. Girls agreed more with the policy of the previous government in its return of the territories in Sinai than boys. Results also showed that the students in the border area as well as boys in both towns were more repressive in their personality type than the students in the more peaceful area and girls of both towns respectively. 相似文献
962.
963.
Hairong Yu Mari Davis Concepcin S. Wilson Fletcher T.H. Cole 《Journal of Informetrics》2008,2(3):240-251
Informetric researchers have long chafed at the limitations of bibliographic databases for their analyses, without being able to visualize or develop real solutions to the problem. This paper describes a solution developed to provide for the specialist needs of informetric researchers. In a collaborative exercise between the fields of computer science and informetrics, data modelling was used in order to address the requirements of complex and dynamic informetric data. This paper reports on this modelling experience with its aim of building an object-relational database (ORDB) for informetric research purposes. The paper argues that ORM (object-relational model) is particularly suitable because it allows for the modelling of complex data and accommodates the various data source formats and standards used by a variety of bibliographic databases. Further, ORM captures the dynamic nature of informetric data by allowing user-defined data types and by embedding basic statistical calculating tools as object functions in these user-defined data types. The main ideas of the paper are implemented in an Oracle database management system. 相似文献
964.
The most common approach to measuring the effectiveness of Information Retrieval systems is by using test collections. The Contextual Suggestion (CS) TREC track provides an evaluation framework for systems that recommend items to users given their geographical context. The specific nature of this track allows the participating teams to identify candidate documents either from the Open Web or from the ClueWeb12 collection, a static version of the web. In the judging pool, the documents from the Open Web and ClueWeb12 collection are distinguished. Hence, each system submission should be based only on one resource, either Open Web (identified by URLs) or ClueWeb12 (identified by ids). To achieve reproducibility, ranking web pages from ClueWeb12 should be the preferred method for scientific evaluation of CS systems, but it has been found that the systems that build their suggestion algorithms on top of input taken from the Open Web achieve consistently a higher effectiveness. Because most of the systems take a rather similar approach to making CSs, this raises the question whether systems built by researchers on top of ClueWeb12 are still representative of those that would work directly on industry-strength web search engines. Do we need to sacrifice reproducibility for the sake of representativeness? We study the difference in effectiveness between Open Web systems and ClueWeb12 systems through analyzing the relevance assessments of documents identified from both the Open Web and ClueWeb12. Then, we identify documents that overlap between the relevance assessments of the Open Web and ClueWeb12, observing a dependency between relevance assessments and the source of the document being taken from the Open Web or from ClueWeb12. After that, we identify documents from the relevance assessments of the Open Web which exist in the ClueWeb12 collection but do not exist in the ClueWeb12 relevance assessments. We use these documents to expand the ClueWeb12 relevance assessments. Our main findings are twofold. First, our empirical analysis of the relevance assessments of 2 years of CS track shows that Open Web documents receive better ratings than ClueWeb12 documents, especially if we look at the documents in the overlap. Second, our approach for selecting candidate documents from ClueWeb12 collection based on information obtained from the Open Web makes an improvement step towards partially bridging the gap in effectiveness between Open Web and ClueWeb12 systems, while at the same time we achieve reproducible results on well-known representative sample of the web. 相似文献
965.
Siobhán Dunne 《New Review of Academic Librarianship》2016,22(4):410-429
The objectives of this study were to identify how, when, and where students research; the impact of learning environments on research productivity, and to recommend improved supports to facilitate research. An ethnographic approach that entailed following five students in the final six weeks of their program enabled deep level analysis. The study examined the practice of undergraduate research inside and outside the library walls and found that the research process can be influenced by a number of factors including age, experience, work commitments, family, peer, academic, and library support. Mobile research is continuing to grow among undergraduate students, particularly those juggling family and work commitments. The research suggests a correlation between intercultural issues such as ethnicity and language with library anxiety. Until they had immersed themselves in the research process, most of the students in this study believed that research was a linear process. 相似文献
966.
Moisés de Hoyo Daniel Dylan Cohen Borja Sañudo Luis Carrasco Alejandro Álvarez-Mesa Juan José del Ojo 《Journal of sports sciences》2016,34(14):1363-1370
ABSTRACTWe analysed the time course of recovery of creatine kinase (CK) and countermovement jump (CMJ) parameters after a football match, and correlations between changes in these variables and match time–motion parameters (GPS-accelerometry) in 15 U-19 elite male players. Plasma CK and CMJ height (CMJH), average concentric force (CMJCON) and average eccentric force (CMJECC) were assessed 2 h before and 30 min, 24 h and 48 h post-match. There were substantially higher CK levels 30 min, 24 h and 48 h (ES: 0.43, 0.62, 0.40, respectively), post-match. CMJECC (ES: ?0.38), CMJH (ES: ?0.35) decreased 30 min post, CMJCON (ES: ?0.35), CMJECC (ES: ?0.35) and CMJH (ES: ?1.35) decreased 24 h post, and CMJCON (ES: ?0.41) and CMJH (ES: ?0.53) decreased 48 h post. We found correlations between distance covered at velocities ≤21 km · h?1 and changes in CK at 24 h (r = 0.56) and at 48 h (r = 0.54) and correlations between CK and distance covered >14 km · h?1 (r = 0.50), accelerations (r = 0.48), and decelerations (r = 0.58) at 48 h. Changes in CMJCON 30 min and 24 h post (both r = ?0.68) correlated with impacts >7.1·G. Decelerations >2 m · s?2 correlated with changes CMJCON (r = ?0.49) at 48 h and CMJECC (r = ?0.47) at 30 min. Our results suggest that match GPS-accelerometry parameters may predict muscle damage and changes in components of neuromuscular performance immediately and 24–48 h post-match. 相似文献
967.
Christian Tolstrup Jensen 《国际体育史杂志》2016,33(10):1079-1098
AbstractThis paper concludes that a number of different discourses marked the coverage of Danish–German sports collaboration during the Second World War in German newspapers, sports magazines and newsreels. From the outbreak of the Second World War to the German occupation of Denmark on 9 April 1940, the discourses cover neutrality and friendship with Germany. After the invasion of Denmark, a discourse of Nordic sentiments became very important in the communications of the press, with Danish athletes portrayed as Nordic citizens, which some circles of German society could interpret as a euphemism for the Nazi idea of a strong Aryan Scandinavia. During the autumn of 1941, the rising strain on Germany’s resources made the sports media a supplier of success. The discourse of a strong Germany replaced the previous discourses. As German–Danish sporting events ceased in 1942, Danish sport alone would still make occasional appearances in the German media until 1944, providing a German audience with entertainment and distraction. 相似文献
968.
Non-circular chainrings alter the crank velocity profile over a pedalling cycle. The aim of this study was to investigate the effect of this altered crank velocity profile on the aerobic performance compared to a circular chainring (CC). Ten male non-cyclists performed two incremental maximal tests at 80?rpm on a cycle ergometer: one with a circular (Shimano) and the other with a non-circular chainring Osymetric® (Somovedi), at least 50?h apart. Each test started with a workload of 100?W lasting 3?min. During the first 12?min, the workload was increased by 30?W every 3?min. Thereafter, the workload was increased by 30?W every 2?min until exhaustion. The power output, the intra-cycle crank angular velocity and the physiological parameters were monitored continuously, averaged over the last 30?s of each increment and at exhaustion, and compared for the two chainrings. Results showed a higher maximal aerobic power attained with the non-circular chainring (362.6?±?37.9 vs. 338.8?±?32.6?W, p?.001; moderate effect), which could be explained by a significantly lower energy expenditure during the first increment at 100?W. It could be hypothesised that the use of the non-circular chainring allowed saving a small part of energy expenditure throughout the test, allowing the exhaustion of the subject at a higher increment for a similar maximal energy expenditure, in comparison with a CC. Although this improvement is obtained only for non-cyclists, it allowed highlighting the link between cycling equipment modifying the pedalling motion and physiological responses. 相似文献
969.
Preschoolers' (M(age) = 48.7 months) social breadth (the number of peer children interact with and the frequency of these interactions) and the relations between breadth and externalizing behaviors were examined using the Q-connectivity method. After considering age, sex, and classroom effects on social breadth, children's externalizing behaviors were studied in relation to levels of social breadth across variations in frequency of exposure to peers and to patterns of decline in social breadth. Externalizing preschoolers occasionally interacted with most of their classmates. However, their individual peer networks moderately to rapidly became selective, and they engaged in repeated interactions with a relatively small number of peers. Although there were no sex effects, significant age and classroom effects were obtained. 相似文献
970.
Musicians, singers and bands can use their popularity to promote various causes and products, either through endorsements or more individual initiatives. Environmental activism is becoming more widespread as humans are trying to tackle and mitigate climate change. In this paper, we ask how best a band can compensate for the carbon emissions generated by fans travelling to its shows. We first report on the various “green” initiatives and practices of the music industry. We then focus on greenhouse gas emissions that result from tours and concerts since they are one of the largest environmental impacts generated by the music industry. We take the perspective of the artist or band wishing to internalize their carbon emissions and present a model of carbon offsets in the context of rock concerts, which amounts to the private provision of a public good. In our model, bands have the option to include offsets in the ticket price or to offer voluntary offsets. To illustrate our point, we present a field study conducted by a Quebec rock band at shows in Montreal and in Europe to show how the artists can reduce the environmental impact of their concert by buying carbon credits equivalent to their fans’ footprint. We show that at 1 % of the ticket price on average, the cost of carbon offsets is marginal and discuss the numerous challenges that arise for those artists wanting to engage in carbon offsetting. 相似文献