Статьи журнала - International Journal of Modern Education and Computer Science
Все статьи: 968
Voltage quality evaluation of distribution network based on probabilistic load flow
Статья научная
Voltage quality for residents of 10kV and below is affected by some factors: voltages of substation 10kV buses, power supply topologies, line types, and power supply distances of 10kV lines, reactive power compensation and loads of distribution transformers. As loads of distribution transformers vary randomly in space and time, voltages of distribution transformers fluctuate randomly as well as distribution network power flows, even network structures and parameters are invariable when voltages of 10kV buses. According to the definition of voltage eligibility rate, a random fluctuation model of distribution transformer loads was built through long term statistical analysis of distribution transformer loads on actual distribution network. By calculating the probabilistic load flows and considering correlation of random fluctuations, static voltages of distribution transformers were analyzed with probability method and power supply voltage eligibility rates of all 10kV lines could be calculated. The simulations show that the power supply voltage eligibility rates can be analyzed and evaluated more comprehensively by probabilistic load flow calculation, such a calculation provides the theoretical calculation basis for both reasonably controlling the bus voltages and improving the power supply voltage eligibility rates.
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Web Pages Retrieval with Adaptive Neuro Fuzzy System based on Content and Structure
Статья научная
Volume of web pages and information on the web is constantly increasing. In this paper, we presented a system to retrieve pages relevant to a query, that can be used by the search engines. The design of our proposed system, content, Page content of neighbors, Connectivity (link analysis) features were used and the methods of fuzzy Sugeno and adaptive fuzzy neural network methods considered .Results showed that the neural method, the error is less than other methods, in the retrieval of web pages tailored to the users search query on the Web, can increase the efficiency of search engines.
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Web Services Privacy Preserving Based on Negotiation and Certificate Authorities
Статья научная
Nowadays, Web services are the leading solution for solving the problem of information systems' integration. Web services are based on the service oriented architecture (SOA). Preserving privacy of web services is one of the main challenges during their interaction. Therefore, minimizing the number of the disclosed credentials that are required for accessing the web services resources during the interaction is a desirable behavior. Credentials generalization and substitution and credentials encryption can be used for privacy preserving. To the best of our knowledge, in the current privacy preserving approaches for web services, there is no technique that uses the negotiation for credential generalization and substitution between the consumer and the provider in conjunction with the credentials encryption using certificate authority as a third party. In this paper, a proposed approach for web services privacy preserving is proposed. This approach is based on the negotiation, encryption, and certificate authorities as third parties. The proposed approach is implemented and tested. The results show that the number of disclosed sensitive credential is the minimum number of credentials that can be disclosed to guarantee the accessing of the service.
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Статья научная
Open Source Software (OSS) provide a number of advantages to Higher Learning Institutions (HLIs) in developing countries, such as Tanzania. This is because they are freely available, free to make copies and free to distribute. Through literature reviewed, it has been observed that OSS usage in HLIs in Tanzania is low due to lack of awareness of OSS designed for academic purposes. This paper presents a study on how to implement a reliable and effective web-based application tool for recommendation of OSS for enhancing awareness of HLIs on existing OSS designed for academic purposes. There are three recommendation algorithms that were employed for filtering the OSS in this study: the content-based, collaborative, and demographic filtering. We used various web technologies for the implementation of application functionalities. The result is the reliable and effective web-based application tool that recommends OSS to individuals in HLIs for enhancing their awareness of OSS designed for academic purposes.
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Web-enabled Simulated and Remote Control Virtual Laboratory of Transducer
Статья научная
In the era of Information and Communication Technology (ICT), virtual laboratories in the field of engineering and sciences have gained popularity, as a smart way of imparting practical and theoretical education. This paper discusses the realization of web-enabled simulated and remote control virtual laboratory of transducer based on one of the modular transducer kit/trainer commonly used in conducting experiments in Instrumentation and Control Engineering curriculum or related fields. Using component-based modeling methods, apparatus/devices used in a particular transducer experiment been have accurately modeled and assembled virtually. The virtual experiment panel mimics the functionality and physical appearance of the actual experimental set up. It provides various options to study and simulate the experiment by varying the input signal or device parameters. The remote control lab facility is also provided that enables the user to remotely perform the experiment on the kit. The experiment is interfaced to PC using suitable data acquisition system. Interactive virtual panel with web-cam connectivity is implemented and published on the web. It allows the user to control the set up and perform the experiment interactively; acquire and analyze real-time data and capture online view of the physical experimental setup remotely. The outcome of this work is the virtualization of transducer based experiments and development of integrated educational tool with high level of pedagogical effectiveness and technical support.
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What Factors Impact Student – Content Interaction in Fully Online Courses
Статья научная
The rapid advancement of fully online courses has made education accessible from "anywhere" and "anytime". One of the major success factors of online courses is effective student - content interaction - which defines how students interact with the content in the fully online learning environment. However, there appears to have been little research published about the relationship of content to course design and consequent outcomes for students. In this article, we report on our research on the investigation of factors that affect student - content interaction in fully online computing courses. We have conducted our research through surveys and used a grounded theoretic approach for data analysis. Our results identify the factors that are perceived by students as critical in ensuring effective student - content interaction in fully online computing courses.
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Статья научная
This study aims to examine how learners engaged in wiki-based collaborative writing when they were using their first language (L1) or second language (L2). Issues concerning similarities and differences in wiki collaborative writing activities, wiki participation levels, wiki interaction patterns and wiki collaboration levels between the L1 and L2 writing groups are discussed. This paper reports a case study of a group of Hong Kong secondary school students who were required to use “Google Sites” to complete their Liberal Studies group projects. Student’s wiki writings and comments in their L1 (Chinese) and L2 (English) were collected and examined. Results indicated that, while similarities in writing activity patterns, participation levels and collaboration levels were shown in the two groups, differences did exist in their interaction patterns, which were affected by the different ways they used the wiki comment sections. This study can help educators to become aware of the different needs of L1 and L2 groups and to implement wiki collaborative writing more effectively to support students.
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Статья научная
In the last two decades many document management systems have evolved and have been deployed for use in business areas such as marketing, production, sales, shipping, banking, education, etc. The demand for electronic document management system has continued to rise with new application areas discovered from day to day. This paper is the first of a two-part study that dwells on the conceptualization, development and deployment of an online documentation system for trade facilitation applications. This paper demonstrates how an organization can build a cost-effective and efficient electronic document management system using open source like MySQL and PHP. The domain of application stressed in this paper is X-ray Cargo Scanning operations as conducted by Government agencies especially the Customs and Excise or their appointees during imports, exports inspection and cargo clearance at the ports. In this paper, the authors investigated various operations that preceed clearance of shipments at ports in Lagos Nigeria. The role of Cargo scanners, image acquisition and subsequent analysis as well as challenges were buttressed. Following the investigation, analysis and design of a solution were done. This paper presents the results of the analysis as well as the system specifications which are considered vital for the implementation of a realtime integrated solution. The proposed system would provide a platform that enhances productivity in a risk management and scanning service organization especially in managing and exchanging large volumes of scanner-generated documentation across a network as well as with other agencies.
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