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51.
In recent years, many U.S. states have introduced growth models as part of their educational accountability systems. Although the validity of growth‐based accountability models has been evaluated for the general population, the impact of those models for English language learner (ELL) students, a growing segment of the student population, has not received sufficient attention. We evaluated three commonly used growth models: value tables or transition matrices, projection models, and student growth percentiles (SGP). The value table model identified more ELL students as on track to proficiency, but with lower accuracy for ELL students. The projection and SGP models were more accurate overall, but classified the fewest ELL students as on track and were less likely to identify ELL students who would later be proficient. We found that each model had significant trade‐offs in terms of the decisions made for ELL students. These findings should be replicated in additional state contexts and considered in the development of future growth‐based accountability policies.  相似文献   
52.
The world culture framework posits a convergence in the organisation of education across the world. On the other hand, scholars observing teaching practices inside classrooms find significant variation among nations and regions of the world. This study examined the global change patterns of classroom practices at the between- and within-country levels, drawing on teacher reports from the Trends in Mathematics and Science Study. Results indicate clear between-country convergence toward more student-centred and conceptual instruction. But a nation’s degree of conformity or resistance to this model was contingent upon other nation-specific factors, including centralised curriculum control or world regional location.  相似文献   
53.
中国省际能源利用效率的空间自相关研究   总被引:2,自引:0,他引:2  
能源效率研究在能源可持续发展和能源环境问题上具有重要的理论和现实意义。结合地理信息系统的空间相关分析功能,对比分析了1995,2000和2003年我国31省市自治区的能源效率与经济发展关系,论证了能源效率不仅与经济发展水平具有明显的空间相关关系和空间集聚性,说明能源效率同样受周围省份影响作用,在区域经济调控和宏观政策制定中必须得考虑这一因素以更好的为能源安全服务。  相似文献   
54.
中学生物理实验操作能力是物理实验能力的核心部分。本文探讨了物理实验操作能力的定义及其特点 ,并在此基础上构建了物理实验操作能力的结构模型 ,讨论了该模型的特点 ,即整体性、静态性、动态性和自调性。根据物理实验操作能力的结构模型及其特点 ,给出了物理实验操作能力的主要指标  相似文献   
55.
This study explored the factors affecting repeat theatrical viewing of movies. Integrating content, social influence, and access/competition variables, the analysis reveals that the drivers of theatrical repeat viewing are different from those for box office performance. For example, the effects of genre, transmedia content, and audience review were significant only for the latter and factors such as movie length, critics’ review, and level of news coverage actually played a negative role in the repeat consumption.  相似文献   
56.
This study employed the uses and gratification approach to investigate how journalists perceive relational satisfaction with the public on Twitter, specifically the associations between journalists’ motivations to use Twitter, their Twitter use, and their relational satisfaction with the public. Through a survey of South Korean journalists, this study revealed that journalists’ motivations for Twitter use are positively related to their job-related activities on Twitter (e.g., posting/sharing their news and interacting with audience), which consequently influences perceived relational satisfaction with the public. The findings provide new insight into an increasingly important part of the public’s engagement and news/information flows in the digital media environment. This study expands upon the literature by analyzing how journalists’ motivations for using Twitter and their job-related activities on Twitter are associated with relational satisfaction with the public.  相似文献   
57.
This study investigated relationships between social media motivation, relative preferences for social media type, and network heterogeneity, using a U.S. national survey. By classifying social media into the symmetrical and the asymmetrical, we showed that relationship motivation was more likely to be associated with a preference for the symmetrical type, whereas information motivation with a preference for the asymmetrical. Network heterogeneity was positively predicted by relationship motivation but not by information motivation. Finally, a relative preference for the symmetrical type was found to mediate the association between relationship motivation and network heterogeneity.  相似文献   
58.
宋国营  常春  苏楠  张媛  郭瑞  石朝云  熊曾 《编辑学报》2016,28(5):453-456
以哮喘机制研究为例,使用GoWeb生物医学专业搜索引擎搜索学科领域研究热点,以PubMed文献检索服务系统来源的国外权威期刊和ISIS系统检索获得的国家自然科学基金项目为评价标准,比较国内权威医学期刊对学科领域研究热点及其发展趋势的把握度.结果发现,免疫学、气道重塑、表观遗传学为哮喘机制研究3大热点,三者发文量或项目数占比之和由高到低排列分别为《中华医学杂志》(96.0%)、国家自然科学基金项目(89.5%)、国外权威期刊(87.0%)、《中华结核与呼吸杂志》(75.7%).与国外权威期刊及国家自然科学基金项目相比较,国内权威期刊中免疫学机制比例较高,而气道重建比例较低,表观遗传学研究见于国外权威期刊、国家自然科学基金项目及《中华医学杂志》中,发文量或项目数占比基本相当;在国内期刊中,《中华医学杂志》对哮喘机制研究热点的把握度较好.基于GoWeb对科技期刊研究领域进行对比分析有利于医学期刊及其编辑把握有关领域的研究热点及其发展趋势,组织发表紧跟国际研究热点的高水平的医学科研论文.  相似文献   
59.
1985年以后,“朦胧诗人”逐渐引退,“朦胧诗”的单向度写作已经不再为更年轻诗人所满足。随着国人艺术观念的解放,诗歌写作风格也日趋多样。以时间为标志的“第三代”、“70后”、“中间代”、“80后”和以作品价值取向为标志的“知识分子写作”、“民间立场”、“下半身”等命名相继出现;各种写作潮流之间分野日益明显,并引发多次论争;民刊的日益兴盛与互联网的出现,使诗歌写作和发表打破了以前官办刊物的垄断地位。这一切,使近20年来的中国诗坛充满活力。  相似文献   
60.
Accelerometer-based systems are often used to quantify human movement. This study’s aim was to assess the reliability and validity of the Myotest® accelerometer-based system for measuring running stride kinematics. Twenty habitual runners ran two 60 m trials at 12, 15, 18 and 21 km·h?1. Contact time, aerial time and step frequency parameters from six consecutive running steps of each trial were extracted using Myotest® data. Between-trial reproducibility of measures was determined by comparing kinematic parameters from the two runs performed at the same speed. Myotest® measures were compared against photocell-based (Optojump Next®) and high-frequency video data to establish concurrent validity. The Myotest®-derived parameters were highly reproducible between trials at all running speeds (intra-class correlation coefficient (ICC): 0.886 to 0.974). Compared to the photo-cell and high-speed video-based measures, the mean contact times from the Myotest® were 34% shorter and aerial times were 64% longer. Only step frequency was comparable between systems and demonstrated high between-system correlation (ICC ≥ 0.857). The Myotest® is a practical portable device that is reliable for measuring contact time, aerial time and step frequency during running. In terms of validity, it provides accurate step frequency measures but underestimates contact time and overestimates aerial time compared to photocell- and optical-based systems.  相似文献   
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