Dynamic Distribution Model with Prime Granularity for Parallel Computing

Dynamic distribution model is one of the best schemes for parallel volume rendering. However, in homogeneous cluster system, since the granularity is traditionally identical, all processors communicate almost simultaneously and computation load may lose balance. Due to problems above, a dynamic distribution model with prime granularity for parallel computing is presented. Granularities of each processor are relatively prime, and related theories are introduced, A high parallel performance can be achieved by minimizing network competition and using a load balancing strategy that ensures all processors finish almost simultaneously, Based on Master-Slave-Gleaner （ MSG） scheme, the parallel Splatting Algorithm for volume rendering is used to test the model on IBM Cluster 1350 system. The experimental results show that the model can bring a considerable improvement in performance, including computation efficiency, total execution time, speed, and load balancing.     

A Model for Socialization Studies in Mental Retardation?

By focusing on how parents protect their children from stressful events and help them both appraise and cope with such events when they occur, Power (this issue) outlines the territory for socialization studies. This commentary examines how Power's tripartite division of parental behaviors (protection, appraisal, coping) can be profitably employed by parents, researchers, and professionals involved with children with mental retardation.     

A Causal Model of Secondary Students’ Achievement in Chemistry

Abstract

A causal model is proposed in order to explain secondary students’ achievement in chemistry; the seven predictor variables used in the explanation are: students’ attitude towards chemistry, understanding of science, scientific attitude, traditional cosmological world‐view, cognitive style, teachers’ attitude towards the teaching of chemistry and understanding of science. Some 460 students chosen by means of stratified cluster sampling and their 25 teachers make up the student and teacher samples, respectively. The numerical values of all the variables are obtained and their intercorrelations computed. Path analysis procedure is applied to the data to estimate the coefficients of the structural equations of the proposed model. The results of the analysis indicate that the hypothesised model is tenable. The seven predictors directly account for 21?6% of the variance in the criterion; their indirect effect is 8?4%. The implications of the findings for chemistry instruction, teacher education and curriculum development are discussed.     

Changes in University Students’ Explanation Models of DC Circuits

One well-known learning obstacle is that students rarely use the concepts in the way that scientists use them. Rather, students mix up closely related concepts and are inclined towards matter-based conceptualisations. Furthermore, some researchers have argued that certain difficulties are rooted in the student’s limited repertoire of causal schemes. These two aspects are conveniently represented in the recent proposal of the systemic view of concept learning. We applied this framework in our analyses of university students’ explanations of DC circuits and their use of concepts such as voltage, current and resistance. Our data consist of transcribed group interviews, which we analysed with content analysis. The results of our analysis are represented with directed graphs. Our results show that students had a rather refined ontological knowledge of the concepts. However, students relied on rather simple explanation models, but few students were able to modify their explanations during the interview. Based on the analysis, we identified three processes of change: model switch, model refinement and model elaboration. This emphasises the importance of relevant relational knowledge at a later stage of learning. This demonstrates how concept individuation and learning of relational structures occurs (and in which order) and sets forth interesting research questions for future research.     

The Effects of Motion Math: Bounce on Students’ Fraction Knowledge

National assessments suggest that many students do not display proficiency with fractions. Considering that time and materials are precious resources, many educators are looking to use technology to provide supplemental instruction with low demand on the instructor. The current study utilized a multiple-baseline design to examine the effects of the Motion Math: Bounce application on the fraction quantity comparison and number line placement skills of three fifth-grade students. Results indicate that Motion Math: Bounce improved the quantity comparison skills of all three participants and the number line skills of one participant. Additionally, all three participants made improvements from pre- to posttest on a measure of general fraction knowledge. Implications for future research and intervention implementation are discussed.     

Impact of Secondary Students’ Content Knowledge on Their Communication Skills in Science

The expert blind spot (EBS) hypothesis implies that even some experts with a high content knowledge might have problems in science communication because they are using the structure of the content rather than their addressee’s prerequisites as an orientation. But is that also true for students? Explaining science to peers is a crucial part of cooperative learning methods such as the “jigsaw method”. Our study examined the relationship between science communication competence (SCC) and content knowledge (CK) of 10th-grade students (N = 213). Using latent class analysis, we identified two types of students with a different relationship between CK and SCC. Using path analysis, we found that the first type of 109 students primarily used their science CK as the “resource” for addressee-oriented science communication and both their SCC and their CK were correlated with each other. For the second type of 104 students (who used other resources), their CK even had a small negative effect on their SCC. Using t tests, we found that those students primarily using their CK as the resource for communication performed significantly worse in the communication test than did those students who used other resources. Using the EBS hypothesis, we suggest that students’ CK might have ambiguous effects in communication if the content structure—rather than their addressee’s prior knowledge—is used as the primary orientation for communication. We suggest that an effective use of cooperative learning techniques in classroom requires a special prior training for their science communication skills.     

Factors Affecting International Students’ Decisions on Destination for Studying Abroad: A Case Study in China

This qualitative study explores how to better attract international students as perceived from the viewpoints of both international students and university administrators. The 7Ps marketing mix conceptual framework and thematic analysis were utilized to analyze qualitative data solicited from both focus group discussions involving 75 international students and in-depth interviews with four administrators at two public universities in Yunnan province, China. The results indicate that two factors mainly affect students’ decisions on an international education destination: geographical location (Place) and cost of study (Price). Furthermore, the study recommends applying the 7Ps as a totality in university recruitment practices.     

Young Children’s Knowledge About the Moon: A Complex Dynamic System

The purpose of this research was to use a multidimensional theoretical framework to examine young children??s knowledge about the Moon. The research was conducted in the interpretive paradigm and the design was a multiple case study of ten children between the ages of three and eight from the USA and Australia. A detailed, semi-structured interview was conducted with each child. In addition, each child??s parents were interviewed to determine possible social and cultural influences on the child??s knowledge. We sought evidence about how the social and cultural experiences of the children might have influenced the development of their ideas. From a cognitive perspective we were interested in whether the children??s ideas were constructed in a theory like form or whether the knowledge was the result of gradual accumulation of fragments of isolated cultural information. Findings reflected the strong and complex relationship between individual children, their social and cultural milieu, and the way they construct ideas about the Moon and astronomy. Findings are presented around four themes including ontology, creatures and artefacts, animism, and permanence. The findings support a complex dynamic system view of students?? knowledge that integrates the framework theory perspective and the knowledge in fragments perspective. An initial model of a complex dynamic system of young children??s knowledge about the Moon is presented.     

A Model for Doctoral Students’ Perceptions and Attitudes Toward Written Feedback for Academic Writing

The purpose of this study is to investigate social science doctoral students’ perceptions and attitudes toward written feedback about their academic writing and towards those who provide it. The study culminates in an explanatory model to describe the relationships between students’ perceptions and attitudes, their revision decisions, and other relevant factors in their written feedback practices. The investigation used a mixed methods approach involving 276 participants from two large mountain west public universities. The main purpose of the qualitative phase was to develop a background for a questionnaire and provisional model to be used in the quantitative phase. Structural Equation Modeling analysis during the quantitative phase provided an eight-factor model that shows the relationships of different factors regarding feedback practices as they relate to doctoral students.     

Uncovering Implicit Assumptions: a Large-Scale Study on Students’ Mental Models of Diffusion

Students’ mental models of diffusion in a gas phase solution were studied through the use of the Structure and Motion of Matter (SAMM) survey. This survey permits identification of categories of ways students think about the structure of the gaseous solute and solvent, the origin of motion of gas particles, and trajectories of solute particles in the gaseous medium. A large sample of data (N?=?423) from students across grade 8 (age 13) through upper-level undergraduate was subjected to a cluster analysis to determine the main mental models present. The cluster analysis resulted in a reduced data set (N?=?308), and then, mental models were ascertained from robust clusters. The mental models that emerged from analysis were triangulated through interview data and characterised according to underlying implicit assumptions that guide and constrain thinking about diffusion of a solute in a gaseous medium. Impacts of students’ level of preparation in science and relationships of mental models to science disciplines studied by students were examined. Implications are discussed for the value of this approach to identify typical mental models and the sets of implicit assumptions that constrain them.     

A US-China Interview Study: Biology Students’ Argumentation and Explanation About Energy Consumption Issues

As China and the United States become the top two carbon emitters in the world, it is crucial for citizens in both countries to construct a sophisticated understanding of energy consumption issues. This interview study examines how U.S. and Chinese students compare in explaining and arguing about two critical energy consumption issues: burning fossil fuels and using electricity. In particular, we focused on using scientific knowledge to explain and argue about these issues. Based on relevant literature and our previous research, we developed a model to guide separate assessment and evaluation of students’ argumentation and explanation. We conducted clinical interviews with 40 biology majors, including 20 U.S. students and 20 Chinese students. This study generated several important findings. First, Chinese students tended to be less consistent across explanations and argumentation, and their levels of argumentation were lower than their levels of explanation. Second, in comparison to their Chinese counterparts, U.S. students provided more scientific arguments but many fewer scientific explanations. Finally, although all participants were college students and had completed at least one introductory level science course before the interviews, some of their explanations and arguments were based on informal ideas rather than matter and energy. We discuss the possible interpretations of these findings and their implications for teaching and learning of scientific explanation and argumentation in both countries.     

The Effects of a Flipped Classroom Model of Instruction on Students’ Performance and Attitudes Towards Chemistry

This study establishes the effects of a flipped classroom model of instruction on academic performance and attitudes of 66 first-year secondary school students towards chemistry. A pre-test and post-test experimental design was employed to assign students randomly into either the experimental or control group. In order to assess the suitability of using flipped model of instruction, students were divided in two groups. For the first group called the experimental group, a “flipped classroom” was used in which the students were given video lessons and reading materials, before the class to be revised at home. On the other hand, the second group followed traditional methodology, and it was used as control. The rate of reaction knowledge test and the chemistry attitude scale were administered. In addition, the researcher documented classroom observations, experiences, thoughts and insights regarding the intervention in a journal on a daily basis in order to enrich the data. Students were interviewed at the end of the research in order to enrich the qualitative data also. Findings from this study reveal that the flipped instruction model facilitates a shift in students’ conceptual understanding of the rate of chemical reaction significantly more than the control condition. Positive significant differences were found on all assessments with the flipped class students performing higher on average. Students in the flipped classroom model condition benefited by preparing for the lesson before the classes and had the opportunity to interact with peers and the teacher during the learning processes in the classroom. The findings support the notion that teachers should be trained or retrained on how to incorporate the flipped classroom model into their teaching and learning processes because it encourages students to be directly involved and active in the learning.     

Darwin’s Difficulties and Students’ Struggles with Trait Loss: Cognitive-Historical Parallelisms in Evolutionary Explanation

Although historical changes in scientific ideas sometimes display striking similarities with students’ conceptual progressions, some scholars have cautioned that such similarities lack meaningful commonalities. In the history of evolution, while Darwin and his contemporaries often used natural selection to explain evolutionary trait gain or increase, they struggled to use it to convincingly account for cases of trait loss or decrease. This study examines Darwin’s evolutionary writings about trait gain and loss in the Origin of Species (On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. D. Appleton, New York, 1859) and compares them to written evolutionary explanations for trait gain and loss in a large (n > 500), cross-cultural and cross-sectional sample (novices and experts from the USA and Korea). Findings indicate that significantly more students and experts applied natural selection to cases of trait gain, but like Darwin and his contemporaries, they more often applied ‘use and disuse’ and ‘inheritance of acquired characteristics’ to episodes of trait loss. Although the parallelism between Darwin’s difficulties and students’ struggles with trait loss are striking, significant differences also characterize explanatory model structure. Overall, however, students and scientists struggles to explain trait loss—which is a very common phenomenon in the history of life—appear to transcend time, place, and level of biological expertise. The significance of these findings for evolution education are discussed; in particular, the situated nature of biological reasoning, and the important role that the history of science can play in understanding cognitive constraints on science learning.     

A Survey on Students’Oral English Ability in High School

Oral communicative ability is of great importance to measure students’English ability.However,it long exists that English course of high schools focuses on grammar.In economically backward cities where high schools don’t treat speaking as a necessity,there is a prevailing phenomenon of high marks but dumb English.Based on the fact above,the author adopts some methods to conduct an investigation among teachers and students in a high school in Shanxi province.After an elaborate collection of data and a comprehensive conclusion of information related to students,the author points out problems existing in students’oral communication in the Grade Two;by analysis,the author points out some possible reasons for these problems;and lastly,the author puts forward some suggestions to these problems accordingly.     

Analysis on Dynamic Performance for Active Magnetic Bearing—Rotor System

In the application of active magnetic bearings(AMB),one of the key problems to be solved is the safety and stabiltiy in the sense of rotor dynamics,The project related to the present paper deals with the method for analyzing bearing rotor systems with high rotation speed and specially supported by active magnetic bearings,and studies its rotor dynamics performance,including calculation of the natural frequencies with their distribution characteristics,and the critical speeds of the system.one of the targets of this project is to formulate a theory and method valid for the analysis of the dynamic performance of the active magntic bearing-rotor systemby combining the traditional theory and method of rotor dynamics with the analytical theory and design method based on modern control theory of the AMB system.