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121.
Peer assessment provides a useful mechanism to develop many positive qualities in students studying in higher education (HE). Potential influences on peer‐awarded marks include student qualities such as gender, HE background (e.g. university affiliation) and participation in the development of the assessment criteria. Many studies that have investigated peer assessment have placed great emphasis on marks from a single tutor, or very few tutors, from a single university. This study examined grades awarded by 11 tutors (affiliated with four universities) to oral presentations delivered on a residential field course by second‐year undergraduate students from two universities studying environmental or biological disciplines. Student assessors awarded marks of fairly high precision (correlating strongly with tutor grades) but averaged 5% higher than their tutors (i.e. of only moderate accuracy). Marginally higher marks (circa 1.6%) were awarded by student assessors to speakers studying at the same university. Gender influences were detected as males tended to grade other male speakers very slightly more highly than female speakers. Marks from females were unaffected by speaker gender. Students who participated in the development of the assessment criteria did not achieve higher grades for their presentations. However, when these ‘participants’ were assessing, they awarded lower marks than their peers (i.e. closer to, but not as low as, those awarded by tutors). Lower marks were also awarded during the middle of sessions, possibly resulting from factors associated with motivation and attention of speakers and markers. Overall, the potential biases in marking by naive assessors examined in this study may influence the validity of marks generated by peer assessment schemes, but the experience of this type of assessment had positive effects on those involved.  相似文献   
122.
Professional development is critical in supporting teachers’ use of technological tools in classrooms. This review of empirical research synthesizes the effective elements of professional development programs that support science teachers in learning about technology integration. Studies are examined that explore how professional development supports technology use within inquiry-based and traditional science instruction. Implications for future research are discussed in four areas: understanding and building on teachers’ beliefs about science and technology; supporting teacher learning by supporting teachers’ examination of students’ work; using technology to support teacher communities and social networks; and sustaining teachers’ learning beyond formal professional development programs.
Tara E. HigginsEmail:
  相似文献   
123.
There has recently been a renewed interest in three types of comparability of standards in the United Kingdom [1] public examination system: between years, between subjects and between the six examination boards. Whilst comparisons of raw grade distributions are now generally acknowledged to be invalid indicators of relative standards, comparisons are regularly made for this purpose between adjusted grade distributions. Such adjustments are typically the result of statistically controlling for some of the relevant variables. The dangers of such an approach are that only easily quantifiable variables are used in the adjustment and that any residual differences between distributions will automatically be attributed to difference in standard. Using candidate‐level data from four 1994 Advanced level (A level) [2] mathematics examinations (designed for 18‐year‐old students), and paying particular attention to the Schools’ Mathematics Project (SMP) 16‐19 [3] syllabus, the paper reports on two such analyses. It then discusses some reasons why attributing differences in the adjusted grade distribution to differences in standard could be invalid. Whilst the study focuses on four A level mathematics syllabuses, the same principles apply irrespective of the context in which statistical comparisons of examination results are made. The methodologies, their shortcomings and the pleas for caution are not, therefore, specific to this study, this type of comparison or this examination system.  相似文献   
124.
复配型特稠原油降粘剂研究   总被引:3,自引:0,他引:3  
文中优化了稠油、特稠油复配型降粘剂的组成配方 .实验表明 ,优化的复配型降粘剂较其单组分的降粘性能明显增强而非优化的复配型降粘剂甚至不及其某些单组分的降粘性能 ,说明复配型降粘剂组分间存在着配伍性和协同效应 .  相似文献   
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126.
Although most Guatemalan rural students currently have access to primary school, there are large differences in the levels of learning that take place among different populations and in different contexts. This paper uses multiple data and methods to examine the interrelated factors underlying achievement disparities in Guatemalan primary schools. The research suggests that strong levels of disadvantage connected to attending schools in poor rural communities are connected to systematic differences in the way school quality is supported in different contexts. There are inadequate resources, capacity, and authority to monitor and enforce fundamental educational issues, especially in marginal communities.  相似文献   
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129.
This is an exploratory study of public library services in Singapore for young people (defined as those people between thirteen to nineteen years of age) who are wheelchair bound. The research was carried out originally in 2000, but the study still informs policy makers in the Singapore system. Three main research questions are explored:
  • What are the information needs of wheelchair-bound young people?

  • What are their perceptions of libraries and library services?

  • What are the problems they face in using library facilities and services?

The study involves eleven wheelchair-bound people between the ages of twelve and twenty who were selected by means of a purposive sample.

Findings indicate that most participants enjoyed reading books but did not read newspapers. The computer was used primarily as a recreational tool, and the convenience of the Internet appealed to them. There were, however, problems in using computer equipment in the libraries. School libraries were generally inaccessible. There were also problems in using public library services and facilities as well as being in public places. Their use of public libraries was infrequent. They were unaware of the full range of library facilities and services.

The study concluded that there was a need and demand for library services by wheelchair-bound young people. Their information needs and reading habits were no different from those of any young person. Current library promotions were inadequate in stimulating or sustaining their awareness and interest. Transportation was the main obstacle in getting to libraries. The problems faced in using libraries were mainly related to architectural and physical access to library facilities and services.  相似文献   
130.
为揭示多级压气机中上下游叶轮对中间叶片叠加气动影响特性,阐述不同叠加干涉情况下下游叶轮进气角度变化,采用数值方法模拟了一级轴流和一级离心组成的组合压气机非定常流场。详细讨论了上游动叶尾迹和下游动叶势流对中间导流叶栅段气流非定常流动的异频和同频叠加干涉特性,依据计算结果,直观地展示了静叶通道中两种干涉间相互激励和抑制作用的位置和时间,与数学公式的推导结果相互印证。研究结果表明:当上下游动叶对中间静叶段异频干涉时,干涉的激励、抑制区域的轴向位置随时间发生变化;当上下游动叶对中间静叶干涉频率相同时,干涉的相互激励、抑制区域的轴向位置不随时间发生变化,但干涉的激励、抑制区域的轴向位置受时序位置影响。另外,上游动叶尾迹与下游离心叶轮势流的不同叠加情况,决定着下游离心叶轮进口相对气流角的大小及波动幅值。   相似文献   
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