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51.
The Student Counselling Needs Scale (SCNS) was administered to 867 participants recruited from high schools in Kenya. The data were analyzed using exploratory factor analysis yielding five factors: human relationships, career development, self development, social values, and learning skills were assessed. The findings highlighted the importance of using assessment instruments to identify students’ counselling needs in Kenya.  相似文献   
52.
It is complicated to design a computer simulation that adapts to students with different characteristics. This study documented cases that show how college students’ prior chemistry knowledge level affected their interaction with peers and their approach to solving problems with the use of computer simulations that were designed to learn electrochemistry. Students with different prior knowledge levels were found to use different approaches to solving problems with the use of computer simulations. In particular, the cases showed that students with a high level of prior knowledge tended to use the equations and formulas to accomplish the learning tasks and then use the computer simulations to confirm their predictions. Students with a low level of prior chemistry knowledge used the computer simulations as the main resources to accomplish their tasks. Considerations of individual differences and the integration of learning materials were suggested for further research on instructional use of computer simulations.  相似文献   
53.
Hamiltonian system for the problem on clamped Mindlin plate bending was established by introducing the dual variables for the generalized displacements in this letter. By separation of variables, the transverse eigen-problem was derived based on the sympletic geometry method. With the solved sympletic eigen-values, the generalized sympletic eigen-solution was derived through eigenfunction expansion. An example of plate with all edges clamped was given. The sympletic solution system was worked out directly from the Hamiltonian system. It breaks the limitation of traditional analytic methods which need to select basis functions in advance. The results indicate that the sympletic solution method could find its more extensive applications.  相似文献   
54.
In this paper we study the scaling behavior of nucleotide cluster in 11 chromosomes of Encephalitozoon cuniculi Genome. The statistical distribution of nucleotide clusters for 11 chromosomes is characterized by the scaling behavior of P(S) ∝ e^-αs' where S represents nucleotide cluster size. The cluster-size distribution P(S1+S2) with the total size of sequential C-G cluster and A-T cluster S1+S2 were also studied. P(S1+S2) follows exponential decay. There does not exist the case of large C-G cluster following large A-T cluster or large A-T cluster following large C-G cluster. We also discuss the relatively random walk length function L(n) and the local compositional complexity of nucleotide sequences based on a new model. These investigations may provide some insight into nucleotide cluster of DNA sequence.  相似文献   
55.
Novel high torque bearingless two-sided rotary ultrasonic motor   总被引:3,自引:0,他引:3  
Applications are limited at present because the currently available ultrasonic motors (USMs) do not provide suffi-ciently high torque and power. The conventional travelling-wave USM needs the bearing to support, which required lubricant. To solve the above problem, a bearingless travelling-wave USM is designed. First, a novel structure of the two-sided USM consisting of a two-sided teeth stator and two disk-type rotors is designed. And the excitation principle of the two-sided travelling-wave USM is analyzed. Then, using ANSYS software, we set up the model of the stator to predict the excitation frequency and modal response of the stator. The shape of the vibration mode was obtained. Last, the load characteristics of the USM are measured using ex-perimental method. The maximum stall torque and the no-load speed were obtained. The results showed that the characteristics of the two-sided USM are better than those of the conventional one-sided USM.  相似文献   
56.
Contemporary international higher education scholarship tends to focus on the global financial crisis,on massification,privatization,cross-border education,university ranking,and student mobility.However,few studies deal with the development of liberal arts programs around the world and they are often related to Western systems of higher education or that of the US,where liberal arts education has long been seen as a fundamental issue.Comparative studies,however,could help scholars to become aware of critical trends and reforms,also the impact they might have on a global society.  相似文献   
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The purpose of this review was to synthesize the research on the relationship between performance on Piagetian tasks of concrete operations and performance on mathematics learning tasks in order to determine whether the Piagetian tasks make useful readiness measures. The research consistently indicates that, while there is a positive correlation between performance on Piagetian tasks and mathematics achievement, many school mathematics tasks can be mastered by children who have not yet developed the reasoning abilities measured by Piagetian tasks. This does not diminish the validity of Piaget's theory, but rather suggests that the kinds of reasoning processes identified by Piaget are not essential in solving many school mathematics tasks.  相似文献   
60.
In the current climate of accountability, action research is one way for teachers to evaluate instructional changes designed to improve assessment results. It may become increasingly common for administrators to mandate teacher involvement in action research, yet few studies have been conducted in such settings. This article focuses on one middle school where the principal mandated action research for all teachers. Projects were carried out within academic departments, and department chairs were given latitude in how to organize and implement projects. This study explores project implementation and teacher perceptions of the action research. Interviews were used as an appropriate tool to explore teacher perceptions, with document analysis providing triangulation. Results from interviews of administrators, department chairs, and department members suggest an overall positive attitude toward action research, as well as variation in how action research projects were carried out. Differences occurred across several dimensions of action research, including context, motivation/ purpose, definition of action research, and organization of projects. Variations appeared to be influenced by each department chair’s experience with action research and approach to departmental work, and each department’s history of working together on instructional improvement efforts. This study suggests that administrators who mandate teacher participation in action research projects need to think about both the positive (providing teacher ownership and interest within the mandated context) and problematic (possibly leading to variation in the instructional impact of projects) aspects of project variation.  相似文献   
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