• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1630-1642
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• 2016

Inter-domain routing is the most critical function of the Internet. The routing system is a logical network relying on the physical infrastructure with geographical characteristics. Nature disasters or disruptive accidents such as earthquakes, cable cuts and power outages could cause regional failures which fail down geographically co-located network nodes and links, therefore, affect the resilience of inter-domain routing system. This paper presents a model for regional failures in inter-domain routing system called REFER for the first time. Based on REFER, the resilience of the inter-domain routing system could be evaluated on a finer level of the Internet, considering different routing policies of intra-domain and inter-domain routing systems. Under this model, we perform simulations on an empirical topology of the Internet with geographical characteristics to simulate a regional failure locating at a city with important IXP (Internet eXchange Point). Results indicate that the Internet is robust under a city-level regional failure. The reachability is almost the same after the failure, and the reroutings occur at the edge of the Internet, hardly affecting the core of inter-domain routing system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.7
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• pp.3100-3116
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• 2016

With the rapid development of urban traffic system and fast increasing of vehicle numbers, the traditional centralized ways to generate the source-destination shortest path in terms of travel time(the optimal path) encounter several problems, such as high server pressure, low query efficiency, roads state without in-time updating. With the widespread use of smart cameras in the urban traffic and surveillance system, this paper maps the optimal path finding problem in the dynamic road network to the shortest routing problem in the smart camera networks. The proposed distributed optimal path generation algorithm employs the delay routing and caching mechanism. Real-time route update is also presented to adapt to the dynamic road network. The test result shows that this algorithm has advantages in both query time and query packet numbers.

• The Journal of Korean Association of Computer Education
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• v.4 no.2
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• pp.165-178
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• 2001

In order to attain a favorable result in the online education, well-developed lectures must be offered with appropriate evaluation feedback process. Internet-based questionnaire systems using CGI or ASP are the most general method under Web environment. This paper informs us of the characteristics and limits of present Internet-based questionnaire systems. For better education and overcoming the limits of the present system, we suggest the practical system which allows teachers to receive feedback from results of a questionnaire, that is easily composed and managed on the Internet using industry standard Microsoft IIS Web server and its embedded server-side script.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.411-420
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• 2006

There are many statistical information sites as the use of internet is increased quickly in recent years. In this paper, we explore and analyze internet sites for statistical information such as statistical survey system, education, database, and terminology. And then we classify these sites to apply statistical information to some particular spheres easily. Also, we analyze the patent map for domestic patents of statistical information. In so doing, the result of this study aims at enhancing our understanding of internet sites for statistical information.

• IE interfaces
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• v.12 no.1
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• pp.56-67
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• 1999

This paper is about implementation issues for use of the Internet technology in education. An examination of the current status of virtual university provides guidance for subsequent prototype development. A virtual university is the Internet based process by which students increase their specific knowledge and skills via electronic interaction with content and people. Virtual university enables colleges and universities to provide students and faculty with network access to courseware and educational materials on multimedia servers free from time and geography constraints. In this paper, we present a prototype instruction support system (ISS). The ISS consists of the following components in architecture: Internet, software, hardware, database systems, users, and workflow. The ISS also assists several functions as follows: lecture notes, register processes, attendance checks, built-in boards, grading systems, questions and answers, electronic libraries, chats, and search engines. Our work will provide a guideline for the development of a virtual classroom for distance education and learning.

• Health Policy and Management
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• v.12 no.2
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• pp.92-114
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• 2002

While making a vigorous discussion about self-regulation for exponential growth of harmful health information on the Internet, many countries lave made various efforts to select and circulate high quality health information on the Internet. The purpose of this study Is to review the serf-regulation methods of health information on the Internet and to suggest quality control methods of health information on the Internet suitable for Korea. Self-regulation methods of the health information on the Internet include ‘content rating system(or content selection system)’, ‘codes of conduct or guideline’, ‘internet hot-line’, ‘education for information providers and consumers’. Any self-regulation method should be used with other methods. We can regulate health information on the Internet effectively by using both self-regulation methods and compulsive methods such as law. Also information providers, information consumers, specialists, consumer representatives, scholars, governments officers should take part in doing these efforts and make concern.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.340-343
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• 1999

In this paper, we developed the cyber campus which is a internet based virtual education system. This system is designed by using the client/server architecture and server push mechanism. The basic design tool is mini SQL and PERL for design and implementation. Developed system is tested on the site of Honam university(cybercam.honam.ac.kr) and confirmed its performance. This tool will be very useful as a distance education method for every school and educational agency under the internet environment.

• Journal of Engineering Education Research
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• v.22 no.1
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• pp.55-60
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• 2019

This paper deals with the process and requirements of a capstone design project performed by undergraduate students. We discuss about the preliminary study for the capstone design, the derivation of a subject, the level descriptor of the subject, and the system requirements. And then, we summarize the results of the capstone design project entitled as Microsoft Azure based IoT (Internet of Things) system which is performed by 4 undergraduate students during 10 months. This system is composed of a Zigbee sensor network, the TCP/IP Internet, an IoT server, and a smartphone application program, with which we can gather the sensor data and control actuators at the far away area.

• Journal of The Korean Association of Information Education
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• v.9 no.3
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• pp.533-548
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• 2005

According to the increasing of the internet infrastructure and growth of contents technology, the users can access an education service at anytime and anywhere. In a field of English education, especially, internet technology has enabled learners to communicate with their teachers and multimedia contents technology has been able to provide learner not only lots of interests, but also good effect on English learning. In this paper, we propose a method diagnosing learner's level by using some question-items, which consist of item's type and item's function. Futhermore, the proposed system can support three devices which are PC, PDA, and Mobile Phone on wired and wireless internet communication environments. Also, the system provides multimedia contents including flash movies, image, and audio contents. We have applied the system into real classroom, and we verified that the question-items that system provides has no problem, and our method could improve each learner skill on English education. Therefore, we expect that learner who uses the proposed system will get level-based English learning service at anytime and anywhere.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.5
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• pp.2063-2081
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• 2018

A resource allocation algorithm is proposed in this paper to simultaneously minimize the total system power consumption and maximize the system throughput for the downlink of multi-user multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) systems. With the Lagrange dual decomposition method, we transform the original problem to its convex dual problem and prove that the duality gap between the two problems is zero, which means the optimal solution of the original problem can be obtained by solving its dual problem. Then, we use convex optimization method to solve the dual problem and utilize bisection method to obtain the optimal dual variable. The numerical results show that the proposed algorithm is superior to traditional single-objective optimization method in both the system throughput and the system energy consumption.