Anisotropic alignments of hierarchical Li2SiO3/TiO2 @nano-C anode//LiMnPO4@nano-C cathode architectures for full-cell lithium-ion battery     

Hesham Khalifa  Sherif A El-Safty  Abdullah Reda  Mohamed A Shenashen  Alaa I Eid 《国家科学评论(英文版)》2020,7(5):863

We report on low-cost fabrication and high-energy density of full-cell lithium-ion battery (LIB) models. Super-hierarchical electrode architectures of Li₂SiO₃/TiO₂@nano-carbon anode (LSO.TO@nano-C) and high-voltage olivine LiMnPO₄@nano-carbon cathode (LMPO@nano-C) are designed for half- and full-system LIB-CR2032 coin cell models. On the basis of primary architecture-power-driven LIB geometrics, the structure keys including three-dimensional (3D) modeling superhierarchy, multiscale micro/nano architectures and anisotropic surface heterogeneity affect the buildup design of anode/cathode LIB electrodes. Such hierarchical electrode surface topologies enable continuous in-/out-flow rates and fast transport pathways of Li⁺-ions during charge/discharge cycles. The stacked layer configurations of pouch LIB-types lead to excellent charge/discharge rate, and energy density of 237.6 Wh kg⁻¹. As the most promising LIB-configurations, the high specific energy density of hierarchical pouch battery systems may improve energy storage for long-driving range of electric vehicles. Indeed, the anisotropic alignments of hierarchical electrode architectures in the large-scale LIBs provide proof of excellent capacity storage and outstanding durability and cyclability. The full-system LIB-CR2032 coin cell models maintain high specific capacity of ∼89.8% within a long-term life period of 2000 cycles, and average Coulombic efficiency of 99.8% at 1C rate for future configuration of LIB manufacturing and commercialization challenges.  相似文献   

Book reviews     

N. L. McCaslin  Douglas Thom  Harold J. Noah  R. Murray Thomas  Emile G. Mc Anany  Michael Eraut  W. Patrick Leonard  John Wilson  Peter McPhail  Haydn Mathias  Mohamed Idwan Ganie  Willy Wielemans  Antonio Valbuena Paz  M. Dino Carelli  Egbert Jahn  Donald K. Sharpes  Daya A. Perera  Friedhelm Zanter  Carole L. Hahn  Walter Hahn  Linda A. Dove  J. A. Akinpelu  Ruth W. Salmon 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1983,29(1):83-119

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Considering mobile device constraints and context-awareness in adaptive mobile learning for flipped classroom     

Fatima Ezzahraa Louhab  Ayoub Bahnasse  Mohamed Talea 《Education and Information Technologies》2018,23(6):2607-2632

Today, the mobile technologies and Information and Communication Technology development opened the door on new methods and pedagogies of learning. We are talking here about the mobile learning and the flipped classroom approaches. The flipped classroom means that the activities that have traditionally taken place inside the classroom now take place outside the classroom and vice versa. The mobile learning and as its name suggests is done in a mobile and changeable environment by mobile learners. Therefore, the context notion plays a significant role in this type of learning. Hence, the usefulness of the context-aware mobile learning systems. These systems take into account the different context dimensions to offer to the learners an adapted learning according to their situations. The approach proposed in this paper called Smart Enhanced Context-Aware for Flipped Mobile Learning “SECA-FML” aims to provide learners with an adapted course content format based on their context by taking into account the different context dimensions and especially the mobile device context. The latter has a significant influence on multimedia content in adaptive mobile learning. The contribution was applied in the context of the flipped learning in order to manage the heterogeneity of context imposed by this approach. To validate our contribution, we have developed an Android mobile application. This application has been made available to learners to try and exploit it. At the end of the experimentation phase, the learner is asked to complete a questionnaire. Based on this questionnaire, we measured the reliability and effectiveness of our contribution, as well as the satisfaction of the learners towards the latter. The evaluation results showed that the use of the context dimensions and specifically the device context in adaptive mobile learning is more beneficial for learners especially in the flipped classroom.  相似文献   

Differences Among Low‐, Average‐ and High‐achieving College Students on Learning and Study Strategies     

Mohamed A. Albaili 《教育心理学》1997,17(1-2):171-177

Abstract The purpose of the present investigation is to examine the differences between low‐, average‐ and high‐achieving college students on the Learning and Study Strategies Inventory scales. A total of 168 undergraduate students at the United Arab Emirates University participated as subjects. Subjects were classified into three achieving groups based on their grade point average (GPA) scores. Analysis of variance procedures indicated that low‐achieving students scored significantly lower than the average‐ and high‐achieving students on all of the scales. However, no significant differences were observed between the average‐ and high‐achieving groups on any of the scales. Furthermore, a stepwise discriminant analysis revealed that Motivation was the most powerful discriminating factor that separated low‐achieving students from their high‐achieving peers.  相似文献   

Can images provide contextual support for prose?     

Robert M. Bernard  Chris H. Petersen  Mohamed Ally 《Educational technology research and development : ETR & D》1981,29(2):101-108

This study sought to determine whether contextual organizers presented before prose passages can improve learning and retention among students who have no prior knowledge of the subject. The researchers used two types of organizers — an image and its verbal equivalent. Students who were provided the organizers scored better than control students on tests given two weeks later, but the predicted advantage of images over verbal learning adjuncts did not appear.  相似文献   

Exploration De La Résilience éducationnelle Chez Des Enseignants     

Manon Théorêt  Roseline Garon  Mohamed Hrimech  Anylène Carpentier 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2006,52(6):575-598

AN EXPLORATION OF THE EDUCATIONAL RESILIENCE OF TEACHING STAFF – This study focuses on the degree of resilience displayed by teaching staff with the aim of promoting their professional development and preventing job-related exhaustion. Seven underprivileged schools in Montreal were selected, and 24 teaching staff with contrasting personal profiles were interviewed on the subject of their work. The Alceste software was used to analyse the conversations, which revolved around techniques applied when dealing with critical incidents. The main analysis identified five different discourses among the respondents. Three of these were associated with the more resilient of the teachers and two were associated with the more vulnerable ones. Resilient teaching staff characteristically discussed dealing with aggressive behaviour, the teaching-learning relationship and the subject of social relationships, whereas vulnerable teaching staff focused on work beyond the classroom, people in positions of higher authority and the community. The authors note that teachers who are just embarking on their careers appear more vulnerable than more experienced teaching staff, which suggests that more resources should be provided to support teachers in their profession.  相似文献   

Arab media,corporate communications,and public relations: the case of Al Jazeera     

Mohamed Zayani 《亚洲交流杂志》2013,23(3):207-222

Over the past few decades, public relations has developed significantly in the West into a sophisticated management function which is recognized as an integral part of any organization's attempt to communicate with various persons, both within and outside the organization, in order to achieve its goals and objectives. However, this is not the case in the Arab world where public relations remains underdeveloped and, even when practised, is relatively unsophisticated. This paper deals with the public relations function in a prominent though controversial Arab media organization: Al Jazeera Satellite Channel. It explores how Al Jazeera has been dealing with internal and external communication issues impelled initially by its role as a satellite broadcaster spearheading changes in a vibrant Arab mediascape and subsequently by its expansion into a global broadcaster. Drawing on James Grunig's four models of communication to analyze Al Jazeera's public relations practices, the case study at hand outlines some of the communication challenges and opportunities the organization has been facing during its 10 years of existence. The case of an indigenous organization like Al Jazeera operating in a culturally distinct environment puts into perspective communications issues and complicates our understanding of how public relations is understood and practised outside the normative Western public relations paradigm.  相似文献   

Perceptions and Knowledge-Sharing Behavior of Pre-University Students     

Shaheen Majid  Chitra Panchapakesan 《International Information and Library Review》2013,45(1-2):30-38

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DESIGN, DEVELOPMENT AND VALIDATION OF A MODEL OF PROBLEM SOLVING FOR EGYPTIAN SCIENCE CLASSES     

Mohamed A. Shahat  Annika Ohle  David F. Treagust  Hans E. Fischer 《International Journal of Science and Mathematics Education》2013,11(5):1157-1181

Educators and policymakers envision the future of education in Egypt as enabling learners to acquire scientific inquiry and problem-solving skills. In this article, we describe the validation of a model for problem solving and the design of instruments for evaluating new teaching methods in Egyptian science classes. The instruments were based on an established model for problem solving and were designed to assess seventh grade students’ problem solving, experimental strategy knowledge, achievement and motivation towards science. The test for assessing students’ knowledge has been developed based on the topic, density and buoyancy which will be taught in seventh grade in a later intervention study. The instruments were partly self-developed and partly adapted from newly performed studies on strategy knowledge and problem solving in Germany. All instruments were translated into Arabic; the translation process and quality control are described. In order to determine the quality of the instruments, 44 students in Egypt completed the questionnaires and tests. The study’s aim to develop and validate the instruments did require an ad hoc and typical sample which was drawn from an accessible population. Accordingly, the characteristics of the sample are described. Data were analysed according to the classical test theory, but to underpin the results, the instruments were additionally analysed using the even stronger Rasch model. The findings demonstrated the reliability of the items and aspects of validity. In addition, this study showed how test items can be successfully developed and adapted in an international study and applied in a different language.  相似文献   

Citizens as consumers: Profiling e-government services’ users in Egypt via data mining techniques   总被引：1，自引：0，他引：1  

Mohamed M. Mostafa  Ahmed A. El-Masry 《International Journal of Information Management》2013

This study uses data mining techniques to examine the effect of various demographic, cognitive and psychographic factors on Egyptian citizens’ use of e-government services. Data mining uses a broad family of computationally intensive methods that include decision trees, neural networks, rule induction, machine learning and graphic visualization. Three artificial neural network models (multi-layer perceptron neural network [MLP], probabilistic neural network [PNN] and self-organizing maps neural network [SOM]) and three machine learning techniques (classification and regression trees [CART], multivariate adaptive regression splines [MARS], and support vector machines [SVM]) are compared to a standard statistical method (linear discriminant analysis [LDA]). The variable sets considered are sex, age, educational level, e-government services perceived usefulness, ease of use, compatibility, subjective norms, trust, civic mindedness, and attitudes. The study shows how it is possible to identify various dimensions of e-government services usage behavior by uncovering complex patterns in the dataset, and also shows the classification abilities of data mining techniques.  相似文献