• The Journal of Information Systems
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• v.17 no.4
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• pp.99-127
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• 2008

E-learning becomes an important part of education these days in Korea. Students had no choice but to accept the e-learning when the e-learning was used as a supplementary learning tool within a traditional class or a stand-alone distance education. This study focuses on the students' intention of e-learning acceptance for voluntary studies. In voluntary study, students have the rights to adopt the e-learning or not for their personal study. We used individual characteristics as the external variables of TAM to explain user acceptance of e-learning for voluntary studies and examined the effect of individual characteristics on user's beliefs. Research model and nine hypotheses were set up to identify the relationships among these variables based on investigations of previous researches. The theoretical model is tested with questionnaires from 420 users who accept e-learning for voluntary studies. We tested the measurement and research models by applying a structural equation modeling(SEM) approach, using the AMOS 5.0. Overall, the results provided support for the model as explaining acceptance of an e-learning system. Most path coefficients in the research model were found statistically significant. The results showed usefulness and enjoyment and subject norm were the factors affecting attitude of students using e-learning. In addition, usefulness and subject norm were the factors affecting intention of students using e-learning. The results show innovation and self-efficacy have a significant impact on user's perception of ease of use. Self-efficacy also have significant effects on user's perception of usefulness.

• The KIPS Transactions:PartD
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• v.9D no.6
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• pp.1091-1096
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• 2002

This paper presents the development of a protein interaction database. The developed system is characterized as follows. First, the proposed system not only maintains interaction data collected by an experiment, but also the genomic information of the protein data. Secondly, the system can extract details on interacting proteins through the developed wrappers. Thirdly, the system is based on wrapper-based system in order to extract the biologically meaningful data from various web sources and integrate them into a relational database. The system inherits a layered-modular architecture by introducing a wrapper-mediator approach in order to solve the syntactic and semantic heterogeneity among multiple data sources. Currently the system has wrapped the relevant data for about 40% of about 11,500 proteins on average from various accessible sources. A wrapper-mediator approach makes a protein interaction data comprehensive and useful with support of data interoperability and integration. The developing database will be useful for mining further knowledge and analysis of human life in proteomics studies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.6
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• pp.1098-1115
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• 2010

An inseparable challenge associated with every random access network is the design of an efficient Collision Resolution Algorithm (CRA), since collisions cannot be completely avoided in such network. To maximize the collision resolution efficiency of a popular CRA, namely Binary Exponential Backoff (BEB), we propose a reactive backoff algorithm. The proposed backoff algorithm is reactive in the sense that it updates the contention window based on the previously selected backoff value in the failed contention stage to avoid a typical type of collision, referred as cross-collision. Cross-collision would occur if the contention slot pointed by the currently selected backoff value appeared to be present in the overlapped portion of the adjacent (the previous and the current) windows. The proposed reactive algorithm contributes to significant performance improvements in the network since it offers a supplementary feature of Cross Collision Exclusion (XCE) and also retains the legacy collision mitigation features. We formulate a Markovian model to emulate the characteristics of the proposed algorithm. Based on the solution of the model, we then estimate the throughput and delay performances of WLAN following the signaling mechanisms of the Distributed Coordination Function (DCF) considering IEEE 802.11b system parameters. We validate the accuracy of the analytical performance estimation framework by comparing the analytically obtained results with the results that we obtain from the simulation experiments performed in ns-2. Through the rigorous analysis, based on the validated model, we show that the proposed reactive cross collision exclusionary backoff algorithm significantly enhances the throughput and reduces the average packet delay in the network.

• Journal of Korea Spatial Information System Society
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• v.7 no.2 s.14
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• pp.15-27
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• 2005

The purpose of this study is to present a methodology of GIS audit system which fully reflects standardization regarding GIS. With the recognition of the problems stemming from data exchange, building costs, and budget waste, this study utilized the standardization for evaluation factors of GIS audit. After analyzing the advantages and disadvantages of current audit methodology, this study pointed out the importance of audit, then presenting main audit factors followed by analyzing national standardization and extracting contents of audit to be added into the existing auditing items. Through the analysis of different types and characteristics, and both advantages and disadvantages of GASP, this study identifies and introduces a highly improved and practical methodology called Modified-GASP (M-GASP) that is basically set to be complementary and supplementary to GASP. Ultimately, the result of this study will support the higher degree of efficiency, stability, and extendability of GIS system, not to mention of strengthening the competitiveness of organizations involved.

• Journal of the Korea Society of Computer and Information
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• v.7 no.2
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• pp.59-67
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• 2002

Major Characteristic of the 7th National Curriculum in science is to provide deep and supplementary learning, depending on the level of each learner. In the level-oriented curriculum, coursewares are used to present teaching materials to various levels. In most coursewares, however, they provide their contents at a uniform level and hence it is hard to expect level-oriented learning. This paper presents learner's modeling for developing student's level-oriented dynamic tutoring system for science class , Instructional module of this system made by component unit is able to be reconstructed dynamically. Learning module is constructed using a hybrid model mixed of Overlay and Bug model. Testing module interprets diagnostic errors to be established by given differentiated weight in accordance with item's difficulty and discrimination. Through ITS student modeling, this system presents various problem solving methods reconstructed by learner's level differentiated.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.1 s.24
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• pp.61-69
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• 2003

The study is the open area keeping a few visible satellites and the urban area covered with the high building, an electric pole were chosen for evaluation of accuracy of satellite positioning. First, suggest the validity of RTK-GPS, RTK-GPS/GLONASS and compared the accuracy with that of the classical surveying method. As a result. In urban area, in case of real time kinematic positioning when compare between the method combined by GPS/GLONASS and by GPS alone the result of GPS/GLONASS - combination more excellent. And in open ana positioning combined GPS/GLONASS was more excellent than GPS alone in both real time differential and real time kinematic. So, RTK-GPS, RTK-GPS/GLONASS contribute to the digital mapping of Basic map and the existed map necessary for the building of PBLIS to the computerization of cadastral map in the effectiveness in time and in cost and hereafter the combined GPS/TS is expected to contribute to the development of NGIS, Re-investigation of a land register, the execution drawing on site.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.5C
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• pp.514-522
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• 2003

Contrary to the previous methods, in this paper, we propose an enhanced shot change detection method using multiple features and binary decision tree. The previous methods usually used single feature and fixed threshold between consecutive frames. However, contents such as color, shape, background, and texture change simultaneously at shot change points in a video sequence. Therefore, in this paper, we detect the shot changes effectively using multiple features, which are supplementary each other, rather than using single feature. In order to classify the shot changes, we use binary classification tree. According to this classification result, we extract important features among the multiple features and obtain threshold value for each feature. We also perform the cross-validation and droop-case to verify the performance of our method. From an experimental result, it was revealed that the EI of our method performed average of 2% better than that of the conventional shot change detection methods.

• Journal of the Korea Society of Computer and Information
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• v.8 no.3
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• pp.188-196
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• 2003

The hazardous enterprise has been increasing its relative importance day by day in the economy of our country and the world. However, it's mostly true to have been relatively neglected in the field of technical strategy. This is to provide for methodological frame about the research in this field in the future by researching on what kind of technical and marketing strategies make what kind of effect on the result of hazardous enterprise together with the strategy for success by meeting the necessity of this research. Therefore, the individual variable within this research was divided into three parts like technical strategy, marketing strategy and industrial environment. It used the type division of venture-company(High-tech type, Superior enterprise type, Boutique type, General enterprise type) as a controllable variable and the result of hazardous enterprise as a subordinate variable. The result of this research is that the technical strategy of hazardous enterprise has lots of possibilities to raise the financial result if it raises technical reform and supplementary character and technical integration level in case that newly-established hazardous enterprise with relatively lower capital power than big enterprise pursues technical strategy.

• Korean Journal of Community Nutrition
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• v.14 no.6
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• pp.846-860
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• 2009

We investigated the foodservice management practices in various operation types of childcare centers in Asan, Chungnam Province, with the intention of improving the quality of foodservice and providing the basic information for establishing more effective and efficient foodservice model system. Self-completed questionnaires were collected from the directors of 174 child care centers. The statistical analysis was completed using SPSS Ver. 12.0 program. The followings are about the results of this study. Approximately 94.8% of the directors were women with the average age of 40.3. All of the investigated facilities executed foodservice; the facilities of 96.2% had been self-operated, 1.9% was contract-managed and the remaining 1.9% served delivered meal from outside. Only 20.0% of the investigated centers employed a dietitian. In most of the centers, meals were prepared in a conventional manner and approximately 85.3% of the centers are serving only snacks twice a day as a supplementary due to financial difficulties. Menu planner of the facilities, which have no dietitian was the director (35.8%) or the cook (25.7%). In most centers, the directors purchased the food materials (67.5%). Material inspection was done by the director (54.9%) or the cook (40.5%). However, home care centers did not inspect the food material. These results indicate that food service management guidelines need to be established by the facility type with the government control and financial support. Especially, dietitian employment and the efficient foodservice model system establishment are questions that confront us.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.81-90
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• 2006

The GNUnet proposed a file encoding method by 1KB block size to support anonimity of files, decentralizes encoded block to peers through unstructed mode and original data decoding method a block searching or encoded blocks. but, the encoding and block decentralizing method with $600\sim700MB$ large multimedia file appered two problems. First problem, it need addition R block and I block, which make about 4% of storage resource. Second problem, unstructured model added network load by broadcasting decentralizing method. Third problem, The critical point of keyword search function. This paper suggest variable encoding block size and structured model by block decentralizing solution. Suggested encoding method reduced block request supplementary block generation from 4% to 1%, network load by proposal structured model sending answer through dedicated peer to decentralize block and we defined content-based keyword and identifier of sharing file.