• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.12
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• pp.3938-3948
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• 1996

This study is related with the experimental investigation on the heat transfer and pressure drop characteristics of the fin-and-tube heat exchangers with three different interrupted fins and a plane fin for air-conditioning application. Experiments were conducted accordingly following the appropriate development process. Geometry similitude experiment was introduced to predict the performance of fins, and prototype experiment was also performed to confirm the validity of geometry similitude experimental results. However, these experimental results were limited to the sensible heat transfer characteristics of the heat exchangers. Hence, additional experiment was performed using refrigerant to investigate the latent heat transfer characteristics. This paper presents an appropriate process for the development of a new type heat exchanger. Sensible and latent heat transfer characteristics for each fin configuration is also provided along with the optimal fin configuration.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.151-155
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• 2012

The cafeteria of university is one of the largest consumption point for the chicken meat of university students. However, few papers conducted research to analyze the consumption behavior of university students. The object of this paper is to conduct survey analysis about the students' behavior for consumption of chicken meat at the cafeterias of university and to measure WTP (Willingness-to-pay) for food cooked with domestic chicken meat. The results present that most of students show higher preference of domestic chicken meat and that they can pay 4,426 Korean won for food cooked with domestic chicken meat.

• Environmental and Resource Economics Review
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• v.21 no.4
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• pp.777-807
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• 2012

This study analyzed the impacts of FTAs (Free Trade Agreements) actively being promoted by the Korean government on the Korean economy, energy consumption and greenhouse gas (GHG) emissions and found the policy implications in terms of the linkage amongst them. The simulation analysis by using a global CGE model, KEEI-GCGE, found that the effectuation of Korea-USA, the Korea-EU and the Korea-China-Japan FTAs at the same time would increase the real gross domestic product (GDP) of Korea by 2.04%. In addition, the energy consumption and GHG emissions of Korea are estimated to increase by 3.33% and 1.53% respectively. These results imply that the various medium and long-term plans and policies related to energy and GHG emissions in Korea should systematically reflect those potential impacts of the FTAs.

• Journal of Digital Convergence
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• v.12 no.12
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• pp.611-620
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• 2014

This research analyzed the operation efficiency and influence factors of housing facilities for the severely disabled in Jeolla region by using the DEA model. First, the analysis of efficiency for 2012 was carried out using the CCR model. As a result, 12 DMUs were proved to be efficient, and the average efficiency of CCR was 0.85, confirming that the efficiency of all DMUs were satisfactory. Second, regression analysis was carried out to analyze the factors affecting the efficiency of the DEA model by using the Tobit model. In this case, the inputs and calculated variables were set as independent variables whereas the efficiency as the dependent variable. As a result, the detailed variables had a low significance; the overall input variables showed a negative influence while the calculated variables tended to be a positive influence. In terms of operation efficiency, there was no meaningful result in input variables besides the number of workers. Instead of expanding the input variables, the following should be made for housing facilities of the severely disabled; more efforts should be put in to improve welfare service delivery system and operating environment and structure, and the program must be supplemented as well.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.4
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• pp.26-40
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• 2018

The aim of this research is to analyze factors affecting bicycle accidents using the PLS structural equation. Accident types in this study were categorized into total accidents, serious injuries including death, and light injuries which occurred at nationwide Si Gun Gu. It was found that urbanization was the main factor for bicycle accidents through the accident models developed in this study. Population, ratio of economically active population, density of intersections, ratio of urbanized area, commercial and industrial land-uses, number of drive license holders, number of education institutions, number of parks were the main factors causing bicycle accidents. Besides, length of bicycle roads, number of bicycles, and ratio of bicycle as mode choice also increased bicycle accidents.

• 한국정보교육학회:학술대회논문집
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• 2011.01a
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• pp.211-217
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• 2011

Recent IT (information technology) environmental changes, such as emerging social network services or increasing user participation in multimedia environment, have made it necessary for e-learning systems to undergo changes in various ways. Metadata is an agreement for interoperability between different systems. The standardization of metadata for e-learning system has been driven by some domestic and international organizations, but applying diverse environmental changes into the design of e-learning metadata is in dire need. In this paper, we present a methodology for the analysis and design of modeling e-learning metadata and elicit the design requirements, on the basis of the metadata standard KEM 3.0, about the elements that are expected to be needed in future e-learning systems. Based on the requirements from the analysis, we present the three-layer model for classifying the requirements by the importance of metadata elements per Kana Model. An intelligent e-learning system is to be developed based on the proposed modeling design, which we hope to influence the development of an international standard in the future.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.631-637
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• 2014

Recently, following the application of modular housing techniques to not only residential sector, but also to business sector, the scope of modular housing market b expanding. In the case of other developed countries, such markets are entering into the maturity stage, though the market in Korea is not fully formed yet. Thus, it is difficult to check its trend to estimated mid- to long-term prospects of the market. In this context, the study predicted demand of the modular housing market by using a non-linear prediction model based on time series analysis. To get the prospects for the modular housing market, the quantity of housing supply was estimated based on the estimated quantity of newly built housings, and assumed that a portion of the supplied quantity would be the demand for modular housings. Based on the assumption of demand for modular housings, several scenarios were analyzed and the prospects of the modular housing market was obtained by utilizing the non-linear prediction model.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.327-334
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• 2020

Recently, mobile and smart devices are rapidly spreading. As a result, real estate services, which were formerly face-to-face, have now been replaced by mobile environments. This study focuses on the real estate app service and 261 samples were used for the empirical analysis. The results of the hypotheses test using structural equation model are summarized as follows. First, performance expectancy, facilitating conditions, security and aesthetic perceived by users of real estate services have positively influence on positive attitude, but effort expectancy and social influence do not. Second, positive attitude of real estate services have positive effects on service Acceptance. Third, involvement moderated the relationship between positive attitude and service Acceptance. Based on the results of the analysis, it provided meaningful implications for practitioners and researchers in related fields.

• The Journal of Korean Association of Computer Education
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• v.14 no.2
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• pp.23-32
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• 2011

The Internet is appearing a new paradigm called Web 2.0 which 'Participation', 'Sharing', 'Openness', 'Cooperation'. Web 2.0 is expanded by experts and general users and many people's ideas can solve more problems than an expert's idea. The collective intelligence is techniques that express the valuable of Web 2.0. For this reason, the collective intelligence has attracted attention because of its potential as an educational tool. The purpose of this study is to develop a PBL-based programming instruction model using collective intelligence to improve students' problem solving abilities and programming attitudes and verified its effectiveness. As a result, the developed instruction model showed significant differences in the students' problem solving abilities and programming attitudes. According to these results, these have been proved that a PBL-based programming instruction model using collective intelligence has an influence to the students' problem solving abilities and programming attitudes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.259-268
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• 2016

The core strategy of transit oriented development (TOD) is to promote high density mixed land use around railway stations. Case studies in advanced countries show that provision of policies for comprehensive maintenance of pedestrian facilities around railway station spheres is being pursued with efficacy. In spite of the importance placed on integrated pedestrian maintenance, domestic construction of integrated pedestrian infrastructure around railway station spheres lacks direction. Thus, there is a clear need for an evaluation standard that can provide the foundation for judgments on TOD improvement. This research proposes a network model that consolidates the interior of the station as well as its surrounding areas to determine the ease of pedestrian flow for effective TOD evaluation. The model considers the railway station and surrounding areas as an assembled network of pedestrian flow. The path chosen by the pedestrian is defined as the optimal degree of inconvenience, and expands on Wardrop's User Equilibrium (1952). To assess the various circumstances that arise on pedestrian facilities including congestion of the pedestrian pathway, constrained elevator capacity, and wait at the crosswalk, a variational inequality based pedestrian equilibrium distribution model is introduced.