Development of lanthanum strontium cobalt ferrite composite cathodes for intermediate- to low-temperature solid oxide fuel cells     

Nurul Akidah BAHARUDDIN  Hamimah Abd RAHMAN  Andanastuti MUCHTAR  Abu Bakar SULONG  Huda ABDULLAH 《浙江大学学报(A卷英文版)》2013,14(1):11-24

Solid oxide fuel cells(SOFCs) offer high energy conversion,low noise,low pollutant emission,and low processing cost.Despite many advantages,SOFCs face a major challenge in competing with other types of fuel cells because of their high operating temperature.The necessity to reduce the operational temperature of SOFCs has led to the development of research into the materials and fabrication technology of fuel cells.The use of composite cathodes significantly reduces the cathode polarization resistance and expands the triple phase boundary area available for oxygen reduction.Powder preparation and composite cathode fabrication also affect the overall performance of composite cathodes and fuel cells.Among many types of cathode materials,lanthanum-based materials such as lanthanum strontium cobalt ferrite(La1-xSrxCo1-yFeyO3- have recently been discovered to offer great compatibility with ceria-based electrolytes in performing as composite cathode materials for intermediate-to low-temperature SOFCs(IT-LTSOFCs).This paper reviews various ceria-based composite cathodes for IT-LTSOFCs and focuses on the aspects of progress and challenges in materials technology.  相似文献   

Science Teachers’ Views and Stereotypes of Religion,Scientists and Scientific Research: A call for scientist–science teacher partnerships to promote inquiry-based learning     

Nasser Mansour 《International Journal of Science Education》2013,35(11):1767-1794

Despite a growing consensus regarding the value of inquiry-based learning (IBL) for students’ learning and engagement in the science classroom, the implementation of such practices continues to be a challenge. If science teachers are to use IBL to develop students’ inquiry practices and encourage them to think and act as scientists, a better understanding of factors that influence their attitudes towards scientific research and scientists’ practices is very much needed. Within this context there is a need to re-examine the science teachers’ views of scientists and the cultural factors that might have an impact on teachers’ views and pedagogical practices. A diverse group of Egyptian science teachers took part in a quantitative–qualitative study using a questionnaire and in-depth interviews to explore their views of scientists and scientific research, and to understand how they negotiated their views of scientists and scientific research in the classroom, and how these views informed their practices of using inquiry in the classroom. The findings highlighted how the teachers’ cultural beliefs and views of scientists and scientific research had constructed idiosyncratic pedagogical views and practices. The study suggested implications for further research and argued for teacher professional development based on partnerships with scientists.  相似文献   

DistanceRank: An intelligent ranking algorithm for web pages     

Ali Mohammad Zareh Bidoki  Nasser Yazdani 《Information processing & management》2008

A fast and efficient page ranking mechanism for web crawling and retrieval remains as a challenging issue. Recently, several link based ranking algorithms like PageRank, HITS and OPIC have been proposed. In this paper, we propose a novel recursive method based on reinforcement learning which considers distance between pages as punishment, called “DistanceRank” to compute ranks of web pages. The distance is defined as the number of “average clicks” between two pages. The objective is to minimize punishment or distance so that a page with less distance to have a higher rank. Experimental results indicate that DistanceRank outperforms other ranking algorithms in page ranking and crawling scheduling. Furthermore, the complexity of DistanceRank is low. We have used University of California at Berkeley’s web for our experiments.  相似文献   

Gender and higher education in different national spaces: Female Palestinian students attending Israeli and Jordanian universities     

Sarab Abu‐Rabia‐Queder  Khaled Arar 《Compare》2011,41(3):353-370

This study examines the higher education experience among Palestinian Arab females in two national spaces and seeks to determine whether studying at an Arab institution of higher learning in a nearby Arab country can alleviate the emotional and economic difficulties that affect Palestinian women at Israeli universities. What can institutions of higher learning in Israel learn or derive from the proposed model to relieve the alienation and exclusion that their female Palestinian students experience? The study will compare two geographically distinct groups of women students. The first is a group of Palestinian women who attend university in Jordan, while the second consists of Palestinian women of Bedouin origin from southern Israel who study in the Jewish Israeli cultural space. The study seeks to shed light on the experience of Muslim students in Western and Muslim universities.  相似文献   

Analysis on fused deposition modelling performance     

Nur Saaidah Abu Bakar  Mohd Rizal Alkahari  Hambali Boejang 《浙江大学学报(A卷英文版)》2010,11(12):972-977

Fused deposition modelling （FDM） is one of rapid prototyping （RP） technologies which uses an additive fabrication approach.Each commercially available FDM model has different types of process parameters for different applications.Some of the desired parts require excellent surface finish as well as good tolerance.The most common parameters requiring setup are the raster angle,tool path,slice thickness,build orientation,and deposition speed.The purpose of this paper is to discuss the process parameters of FDM Prodigy Plus （Stratasys,Inc.,Eden Prairie,MN,USA）.Various selected parameters were tested and the optimum condition was proposed.The quality of the parts produced was accessed in terms of dimensional accuracy and surface finish.The optimum parameters obtained were then applied in the fabrication of the master pattern prior to silicone rubber moulding （SRM）.These parameters would reduce the post processing time.The dimensional accuracy and surface roughness were analyzed using coordinate measuring machine （CMM） and surface roughness tester,respectively.Based on this study,the recommended parameters will improve the quality of the FDM parts produced in terms of dimensional accuracy and surface roughness for the application of SRM.  相似文献   

Performance contagion and human resource layout: New concepts in performance management     

Farid Ahmadi  Nasser Mirsepassi 《Performance Improvement》2010,49(1):25-33

Job performance can be defined as the extent to which one exhibits behaviors that further the goals of the organization, and leaders try to manage the factors influencing the performance in an organization to guide it toward organizational goals. A main factor that influences the performance is emotions and behavior of other people. The influence of people on each other can be divided into physical and metaphysical contagions in the scientific literature. In this article, we introduce a new kind of metaphysical contagion that has a close relationship with individual and organizational performance. We name it performance contagion and introduce two kinds of factors (content and process) and subfactors. We conceptualize a new concept in performance management defined as human resource layout. Tools are suggested for applying the steps of this model to improve both individual and organizational performance.  相似文献   

Student‐centered integrated anatomy resource sessions at Alfaisal University     

Michèle Cowan  Nasir Nisar Arain  Tawfic Samer Abu Assale  Abdulelah Hassan Assi  Raed Alwai Albar  Paul K. Ganguly 《Anatomical sciences education》2010,3(5):272-275

Alfaisal University is a new medical school in Riyadh, Kingdom of Saudi Arabia that matriculates eligible students directly from high school and requires them to participate in a hybrid problem‐based learning (PBL) curriculum. PBL is a well‐established student‐centered approach, and the authors have sought to examine if a student‐centered, integrated approach to learn human structures leads to positive perceptions of learning outcomes. Ten students were divided into four groups to rotate through wet and dry laboratory stations (integrated resource sessions, IRSs) that engaged them in imaging techniques, embryology, histology, gross anatomy (dissections and prosections), surface anatomy, and self‐directed learning questions. All IRSs were primarily directed by students. During two second‐semester organ system blocks, forty students responded to a structured questionnaire designed to poll students' perceptions of changes in their knowledge, skills, and attitudes as a result of IRS. The majority (60%) of students felt that the student‐centered approach to learning enhanced their medical knowledge. Most students also felt that the IRS approach was advantageous for formulating clear learning objectives (55%) and in preparing for examinations (65%). Despite their positive feelings toward IRS, students did not view this learning approach as an adequate replacement for the knowledge gained from lectures and textbooks. Students' performance on objective structured practical examinations improved significantly for the two curricular blocks that included IRS compared with earlier non‐IRS blocks. A student‐centered approach to teach human structure in a hybrid PBL curriculum may enhance understanding of the basic sciences in first‐year medical students. Anat Sci Educ 3:272–275, 2010. © 2010 American Association of Anatomists.  相似文献   

The concurrent validity of the Cognitive Levels Test with the Wechsler Intelligence Scale for Children-Revised for a sample of referred children and youth     

Booney Vance  Larry Mayes  Ronald C. Eaves  Naim Abu Homos 《Psychology in the schools》1991,28(2):100-105

The present investigation compared the Cognitive Levels Test (CLT) and the Wechsler Intelligence Scale for Children-Revised (WISC-R) scores for 55 children who were referred for remedial educational services. A comparison of the correlations for each of the criterion measures from the WISC-R showed a consistent significant positive relationship with the CLT. A repeated measures analysis of variance that compared standard scores for the CLT with those of the WISC-R indicated that significant differences existed between WISC-R IQs and the CLT Cognitive Index. Implications concerning the validity of the Cognitive Levels Test are discussed.  相似文献   

SCIENCE TEACHERS’ TYPOLOGY OF CPD ACTIVITIES: A SOCIO-CONSTRUCTIVIST PERSPECTIVE     

Heba EL-Deghaidy  Nasser Mansour  Saeed Alshamrani 《International Journal of Science and Mathematics Education》2015,13(6):1539-1566

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Using a Moodle-Based Professional Development Program to Train Science Teachers to Teach for Creativity and its Effectiveness on their Teaching Practices     

Sulaiman M. Al-Balushi  Nasser S. Al-Abdali 《Journal of Science Education and Technology》2015,24(4):461-475

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