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961.
The proposed work aims to explore and compare the potency of syntactic-semantic based linguistic structures in plagiarism detection using natural language processing techniques. The current work explores linguistic features, viz., part of speech tags, chunks and semantic roles in detecting plagiarized fragments and utilizes a combined syntactic-semantic similarity metric, which extracts the semantic concepts from WordNet lexical database. The linguistic information is utilized for effective pre-processing and for availing semantically relevant comparisons. Another major contribution is the analysis of the proposed approach on plagiarism cases of various complexity levels. The impact of plagiarism types and complexity levels, upon the features extracted is analyzed and discussed. Further, unlike the existing systems, which were evaluated on some limited data sets, the proposed approach is evaluated on a larger scale using the plagiarism corpus provided by PAN1 competition from 2009 to 2014. The approach presented considerable improvement in comparison with the top-ranked systems of the respective years. The evaluation and analysis with various cases of plagiarism also reflected the supremacy of deeper linguistic features for identifying manually plagiarized data.  相似文献   
962.
Introduction: Social roles in physical education (PE) classes have been much studied, especially mentoring and coaching roles. The studies have shown that mentoring and coaching are beneficial not only for motor learning, but also for methodological and social learning. To our knowledge, the role of the student referee in PE lessons has never been specifically studied. Yet refereeing is essential in many sports, including team sports, and provides an experience of responsibility that many teachers want to offer their students. Encouraging students to take on this role can nevertheless be difficult.

Objective: The objective of the present study was to gain access to students’ lived experiences as referees in order to determine their strategies for being effective. We particularly wanted to determine which concerns organized their activity so that we could identify a refereeing typology that would be useful for PE teaching. Our study is original in that we did not rely exclusively on experiential data to understand student refereeing activity. We also collected data on the students’ motivation in order to better understand their experiences. For this purpose, the study was conducted within the methodological framework of course-of-action theory and self-determination theory.

Method: Seventy-four students from three classes in the third year of middle school (about 13 years old) participated in the study. Among them, four (two girls and two boys and not experts in the sports in which they were going to referee) had volunteered to be filmed and to participate in self-confrontation interviews. The other students completed two questionnaires to provide information on their motivation for refereeing. The situations studied were basketball and handball matches held at the end of the lessons.

Two categories of data were collected: qualitative and quantitative. The qualitative data were based on audiovisual recordings of the students as they refereed matches and verbalization data from self-confrontation interviews; these data were used to document the students’ courses of experience during the activity period under study. The quantitative data were collected using two questionnaires, one to assess the determinants of motivation and the other to assess self-determined motivation.

Results and discussion: The qualitative analysis highlighted three typical student involvements: fulfilling the role of referee, getting help, and occasionally dropping out of the role. The quantitative analysis revealed that the students in the social role of referee mainly expressed amotivation, external regulation, and intrinsic motivation toward knowledge and accomplishment.

The results are discussed around two major points: (1) the students’ strategies of alternation from which their refereeing activity emerged and (2) proposals for PE teacher interventions.  相似文献   

963.
目的:观察8周规律游泳运动对脑组织不同区域的氧化应激体系和DNA损伤的影响。方法:符合实验条件的24只雄性SD大鼠随机分为两组:安静组、递增负荷8周规律游泳组。采用免疫组化染色和生物化学检测方法,观察8周规律游泳运动对脑组织不同区域丙二醛(MDA)含量和谷胱甘肽过氧化物酶(GSH-PX)活性以及8-羟基-2’-脱氧鸟苷(8-OHdG)表达情况的影响。结果:8周规律游泳可以使大鼠海马组织的GSH-PX活性增加,同时MDA含量降低(p<0.05);但皮层GSH-PX活性及MDA含量与安静组相比无统计学意义;DNA损伤的产物8-OHdG表达在皮层和海马组织中与安静组之间无差别。结论:规律游泳运动可增加海马组织GSH-PX活性,对皮层GSH-PX活性无影响;运动对皮层和海马组织GSH-PX活性的影响不同,但并没有增加皮层的DNA损伤,可能是氧化应激过程中不同脑区的调节机制不同。  相似文献   
964.
探讨急性亚极量运动诱发机体免疫抑制蛋白(Immune Suppressive Protein of Stress,ISPS)出现的最短时间。方法:以北京体育大学研究生院8名健康学生为研究对象,实施急性亚极量强度跑台运动,受试者分别于运动前、运动后24 h无菌采集静脉血进行指标测定。结果发现,急性亚极量运动后24 h机体内ISPS水平升高,证实在急性运动后短至24 hISPS就能在人体内被诱导出现。结论:与运动前相比,急性亚极量运动应激24 h后,受试者血清对正常小鼠ConA诱导的淋巴细胞增殖具有明显的抑制作用,是血清中ISPS蛋白水平升高引起。  相似文献   
965.
政策是发展职业教育的根本动力与保证   总被引:1,自引:0,他引:1  
高峰 《职大学报》2010,(1):129-131
学报学报,学术报道,理应主要刊发各科学术研究的成果;但因学报的服务对象主要是高等院校的广大教师,因此探讨教育教学工作经验、体会的文章,也不能不适当刊发若干。但是,近年此类经验体会之类的来稿实在太多,而本刊版面又有限制,故编辑部作出以下决定:一、此类稿件的采用率严格控制在二十分之一以下;二、此类稿件不再附加"摘要"、"关键词"、"作者简介"等等内容。恳切希望广大作者和读者理解并配合我们的工作。  相似文献   
966.
高校信息化建设中的CIO角色研究及启示   总被引:8,自引:0,他引:8  
在高校信息化建设中,如何统一战略规划,实现资源共建共享,建立与完善部门协调工作机制,并进一步推动高校管理体制的数字化、高效能重组,不仅已成为越来越多大学领导者的共识,而且成为大学改革深化发展的一种新趋势.本文对CIO体制的历史演变和CIO角色、职责、能力特征进行了较为深入的考察,并提出对我国高校信息化建设的启示.  相似文献   
967.
校长培训中专业教师的作用至关重要。培训具有培养学习气氛;激发学习愿望;创设多种形式;讲究交流互动;提升实战能力五大特征。专业教师认清自己的教师角色、教练角色、咨询角色、管理角色,才能使校长培训工作卓有成效。必要的行动策略是:分析培训需求、设计培训方案、开发培训课程、梳理办学问题、提炼实践经验、评估培训绩效。  相似文献   
968.
Dissipation mechanisms of excess photon energy under high-temperature stress were studied in a subtropical forest tree seedling, Ficus concinna. Net CO2 assimilation rate decreased to 16% of the control after 20 of high-temperature stress, and thus the absorption of photon energy exceeded the energy required for CO2 assimilation. The efficiency of excitation energy capture by open photosystem Ⅱ (PSII) reaction centres (Fv'/Fm') at moderate irradiauce, photochemical quenching (qp), and the quantum yield of PSII electron transport (φPSII) were significantly lower after high-temperature stress. Nevertheless, non-photochemical quenching (qHP) and energy-dependent quenching (qE) were significantly higher under such conditions. The post-irradiation transient of chlorophyll (Chl) fluorescence significantly increased after the turnoff of the actinic light (AL), and this increase was considerably higher in the 39 ℃-grown seedlings than in the 30 ℃-grown ones. The increased post-irradiation fluorescence points to enhanced cyclic electron transport around PSI under high growth temperature conditions, thus helping to dissipate excess photon energy non-radiatively.  相似文献   
969.
Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% (w/v) chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize (Zea mays L.) inbred lines, HuangC (chilling-tolerant) and Mo17 (chilling-sensitive). While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time (MGT), and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde (MDA) content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase (POD) activity, and catalase (CAT) activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60~64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.  相似文献   
970.
社会公正与大学角色   总被引:1,自引:0,他引:1  
Social justice is not only a vital ethical principle of the human society but also the all-important value of the entire social system. As a public sphere, the university undertakes the purpose to achieve public interest. It plays a significant role in reflecting, defending, and fostering social justice. Nurturing people with social justice awareness is a key mission of the university; it communicates and advocates the ideas of social justice, which helps to foster social justice consciousness of the public; and, for its own part, it must strive to embody and defend procedural justice. __________ Translated from Gaodeng Jiaoyu Yanjiu 高等教育研究 (Journal of Higher Education), 2007, 28(1): 13–19, revised by Zha Qiang, Faculty of Education, York University  相似文献   
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