浅析CNMARC格式中的字段指示符

机读目录的字段指示符，在录入机编数据时，容易被忽视或漏掉，致使书目数据库的字段指示符混乱，造成CNMARC格式与其他元数据格式转换困难。在此通过对字段指示符的分析，确定其在CNMARC格式中的重要性，同时指明其赋值情况。     

On the cultural validity of science assessments

We propose the concept of cultural validity as a form of test validity in science assessment. The conceptual relevance of cultural validity is supported by evidence that culture and society shape an individual's mind and thinking. To attain cultural validity, the process of assessment development must consider how the sociocultural context in which students live influences the ways in which they make sense of science items and the ways in which they solve them. These sociocultural influences include the values, beliefs, experiences, communication patterns, teaching and learning styles, and epistemologies inherent in the students' cultural backgrounds, as well as the socioeconomic conditions prevailing in their cultural groups. We contend that current approaches to handling student diversity in assessment (e.g., adapting or translating tests, providing assessment accommodations, estimating test cultural bias) are limited and lack sociocultural perspective. We find that attaining cultural validity may conflict with current basic principles and assumptions in testing, such as item independence and standardization. We discuss the ways in which adopting cultural validity as a criterion for test validity makes it necessary to shift assessment paradigms and adopt new procedures for assessment development. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 553–573, 2001     

A cross-national study of teacher’s perceptions of online learning success

This study examines success factors in online learning from the instructors’ perspective. Academic success comprises not only student satisfaction and good grades, but also perception of learning and knowledge transfer. A systemic model of inputs–process–outputs of learning was used. A total of 322 online teachers from four different universities and countries were used to study factors of attainment. Findings suggest that: (i) instructors from the University of Peking and the Autonomous Popular University of the State of Puebla reported learner factors as the most important for students on online courses, (ii) instructors from the University of New Mexico perceived institutional factors as the most important for establishing effective online learning and (iii) instructors from the Open University of Catalonia reported outcome factors as the most important for learners in online courses. Compared with other research results in online learning, instructors in this study generally reflect a greater concern about the content, social presence, instruction and their interactions than about technological matters.     

西部矿产资源分析与政策探讨

当今世界面临着人口、资源与环境三大热点问题,要使资源、生态环境与社会经济发展相协调,选择可持续发展的道路已成为世界各国的共识.本文通过研究西部矿产资源的环境承载力,应用环境承载力的综合量化模型,构建西部地区环境承载力评价指标体系,对2010年西部矿产资源的承载力指标数值进行了预测,提出西部矿产资源相应的开发战略和政策建议.     

Manufacturing and wetting low-cost microfluidic cell separation devices

Deterministic lateral displacement (DLD) is a microfluidic size-based particle separation or filter technology with applications in cell separation and enrichment. Currently, there are no cost-effective manufacturing methods for this promising microfluidic technology. In this fabrication paper, however, we develop a simple, yet robust protocol for thermoplastic DLD devices using regulatory-approved materials and biocompatible methods. The final standalone device allowed for volumetric flow rates of 660 μl min⁻¹ while reducing the manufacturing time to <1 h. Optical profilometry and image analysis were employed to assess manufacturing accuracy and precision; the average replicated post height was 0.48% less than the average post height on the master mold and the average replicated array pitch was 1.1% less than the original design with replicated posts heights of 62.1 ± 5.1 μm (mean ± 6 standard deviations) and replicated array pitches of 35.6 ± 0.31 μm.     

试述利用高中和标准化考试成绩确定大学申请学生的合格性──美国加州大学的经验与启示

本文以美国加州大学的招生实践为基础,分析高中成绩和标准化入学考试分数对大学一年级成绩的预测效度,以及它们在评定大学申请学生合格性中的作用,同时也阐述了加州大学利用这两种成绩确定申请学生合格性方法的问题与面临的挑战。研究表明,高中成绩对大学一年级成绩的预测效度高于标准化考试(SATI)。但高中成绩主要反映了学生掌握高中知识的程度,而标准化考试成绩则侧重于体现学生的认知能力。合理结合、使用这两种成绩对学生的知识和能力进行评价,将会使大学招生更为科学公允。     

用传感技术改造汽车的点火及配气系统

传感技术在高速发展时汽车工业中有广泛的应用，如发动机点火正时，配气系统，防抱总制的系统的控制，汽车电气装置等、可以预见，传感技术在汽车上应用具有广阔的前景。