城市承办大型体育赛事生态风险评估体系的构建研究

大型体育赛事为城市发展创造良好的社会效益和经济效益的同时,也在一定程度上给城市生态环境带来了风险。运用文献资料法、专家调查法、层次分析等方法对城市承办大型体育赛事带来的生态风险类型、风险源、风险受体进行了分析,构建出一个由4个一级指标、14个二级指标、40个三级指标组成的生态风险评估体系。结果表明:城市承办大型体育赛事的生态风险类型主要分为生态失衡风险、生态空间占用风险、环境污染累积集中爆发风险、资源能源无序利用过度消耗风险;生态环境指标是诱发城市生态风险的首要因素,生态空间指标是诱发城市生态风险的次要因素,生物种群和能源资源指标是诱发城市生态风险的第三和第四个因素。结果显示在大型体育赛事承办过程中首先要加强对城市生态环境污染的防治;其次要做好城市建设规划,防止造成对城市生态空间和生态环境的剥夺与胁迫;再次,做好城市人口规划,合理控制外来人口规模;最后要提高城市居民环保意识,构建全民参与的生态环保社会行动体系。     

User Navigation in Large-Scale Distributed Digital Libraries: The Case of the Digital Public Library of America

ABSTRACT

This article presents the findings of a case study that examined user navigation in a large-scale digital library in the context of academic use. Using the Digital Public Library of America (DPLA) as a case, the study explored user navigation and understanding of a distributed model of large-scale digital libraries. The DPLA model involves two- or three-step navigation pathways. Most study participants could navigate the DPLA distributed, multilayered system effectively. This study found some confusion among the participants when they must move through a three-step process to locate digital objects provided by a metadata aggregator service hub. The study participants also pointed out the advantages of a distributed model in collocating digital resources and connecting users to a wide range of digital libraries.     

工业4.0背景下职业学校五年制机械制造及自动化专业人才的工作岗位探讨

中国工业4.0将推动我国制造业由大变强,将为传统制造业发展方式带来颠覆性和革命性的变化。通过阐述工业4.0的内涵,对机械制造业中工业4.0重要标志性的基础装备数控机床加工以及规模化生产流水线的生产方式进行了分析,指出职业学校五年制机械制造及自动化专业面临的就业导向目标变化,为本专业的人才培养计划提供修正依据。     

大型工程项目建设管理中关键路径法和关键链法的应用

利用关键路径法和关键链法解决大型工程项目建设管理中的问题,分析AOE网络中寻找关键路径和关键活动的方法,介绍了在约束集理论上的关键链法的基本思想,并指出根据不同项目建设需求,在大型工程项目建设管理中对关键路径和关键活动方法的应用．     

一类广义大系统的稳定性

广义大系统的稳定性是一个非常有意义的问题,由于广义大系统的复杂性,对其稳定性的研究也是一件比较困难的事情．给出了广义大系统渐近稳定的一个充分条件,得到了一个与矩阵的特征值无关的参数域,因此,对于一些广义大系统,能够较快地判断出它的稳定性．     

Mean Effects of Test Accommodations for ELLs and Non‐ELLs: A Meta‐Analysis of Experimental Studies

The objective was to examine the impact of different types of accommodations on performance in content tests such as mathematics. The meta‐analysis included 14 U.S. studies that randomly assigned school‐aged English language learners (ELLs) to test accommodation versus control conditions or used repeated measures in counter‐balanced order. Individual effect sizes (Glass's d) were calculated for 50 groups of ELLs and 32 groups of non‐ELLs. Individual effect sizes for English language and native language accommodations were classified into groups according to type of accommodation and timing conditions. Means and standard errors were calculated for each category. The findings suggest that accommodations that require extra printed materials need generous time limits for both the accommodated and unaccommodated groups to ensure that they are effective, equivalent in scale to the original test, and therefore more valid owing to reduced construct‐irrelevant variance. Computer‐administered glossaries were effective even when time limits were restricted. Although the Plain English accommodation had very small average effect sizes, inspection of individual effect sizes suggests that it may be much more effective for ELLs at intermediate levels of English language proficiency. For Spanish‐speaking students with low proficiency in English, the Spanish test version had the highest individual effect size (+1.45).     

Validating English Language Proficiency Assessment Uses for English Learners: Academic Language Proficiency and Content Assessment Performance

States use standards‐based English language proficiency (ELP) assessments to inform relatively high‐stakes decisions for English learner (EL) students. Results from these assessments are one of the primary criteria used to determine EL students’ level of ELP and readiness for reclassification. The results are also used to evaluate the effectiveness of and funding allocation to district or school programs that serve EL students. In an effort to provide empirical validity evidence for such important uses of ELP assessments, this study focused on examining the constructs of ELP assessments as a fundamental validity issue. Particularly, the study examined the types of language proficiency measured in three sample states’ ELP assessments and the relationship between each type of language proficiency and content assessment performance. The results revealed notable variation in the presence of academic and social language in the three ELP assessments. A series of hierarchical linear modeling (HLM) analyses also revealed varied relationships among social language proficiency, academic language proficiency, and content assessment performance. The findings highlight the importance of examining the constructs of ELP assessments for making appropriate interpretations and decisions based on the assessment scores for EL students. Implications for policy and practice are discussed.     

中国影视文化贸易的现状和对策分析

我国影视文化贸易仍处于逆差地位,但近年来,影视文化产业表现出前所未有的活跃景象,势头正劲,不可抵挡。从现状来看,存在的主要问题有：贸易逆差巨大,影视产品类型及进出口国家过分集中,影视产业地位虽有所转变,但占世界份额小等。通过分析以上问题产生的原因,提出一些有效的解决措施,为我国影视产业发展提供一点思路。     

Formative assessment in mathematics for engineering students

In this paper, we present a range of formative assessment types for engineering mathematics, including in-class exercises, homework, mock examination questions, table quizzes, presentations, critical analyses of statistical papers, peer-to-peer teaching, online assessments and electronic voting systems. We provide practical tips for the implementation of such assessments, with a particular focus on time or resource constraints and large class sizes, as well as effective methods of feedback. In addition, we consider the benefits of such formative assessments for students and staff.     

制度视野下的农地规模化流转探讨——兼谈促进我国农地规模化流转的对策

在农地规模化流转的过程中一系列制度的完善和构建极其重要。文章从宏观的制度环境是农地规模化流转的基本前提、微观的流转规范是促进规模化流转的必要条件、政府的服务制度是农地规模化流转的重要因素等几个方面对我国的农地流转、农地规模化发展加以研究,并提出了促进我国农地规模化流转的对策,力图为我国农地规模化经营、农业现代化经营提供理论指导。