• Earthquakes and Structures
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• v.21 no.5
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• pp.505-514
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• 2021

A formulation based on structural reliability and cost effectiveness is proposed to provide recommendations to select the best retrofit strategy for schools with reinforced concrete frames and masonry walls, among three proposed alternatives. The cost calculation includes the retrofit cost and the expected costs of failure consequences. Also, the uncertainty of the seismic hazard is considered for each school site. The formulation identifies the potential failure modes, among shear and bending forces for beams, and flexure-compression forces for columns, for each school, and the seismic damages suffered by the schools after the earthquake of September 17, 2017 are taken into account to calibrate the damaged conditions per school. The school safety level is measured through its global failure probability, instead of only the local failure probability. The proposed retrofit alternatives are appraised in terms of the cost/benefit balance under future earthquakes, for the respective site seismic hazard, as opposed to the current practice of just restoring the structure original resistance. The best retrofit is the one that corresponds to the minimum value of the expected life cycle cost. The study, with further developments, may be used to develop general recommendations to retrofit schools located at seismic zones.

• Journal of Korea Water Resources Association
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• v.55 no.6
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• pp.405-419
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• 2022

Flood frequency analysis commonly used to design the hydraulic structures to minimize flood damage includes uncertainty. Therefore, the most appropriate design flood within a uncertainty should be selected in the final stage of a hydraulic structure, but related studies were rarely carried out. The total expected cost function introduced into the flood frequency analysis is a new approach for determining the optimal design flood. This procedure has been used as UNCODE (UNcertainty COmpliant DEsign), but the application has not yet been introduced in South Korea. This study introduced the mathematical procedure of UNCODE and calculated the optimal design flood using the annual maximum inflow of hydroelectric dams located in the Bukhan River system and results were compared with that of the existing flood frequency. The parameter uncertainty was considered in the total expected cost function using the Gumbel and the GEV distribution, and the Metropolis-Hastings algorithm was used to sample the parameters. In this study, cost function and damage function were assumed to be a first-order linear function. It was found that the medians of the optimal design flood for 4 Hydroelectric dams, 2 probability distributions, and 2 return periods were calculated to be somewhat larger than the design flood by the existing flood frequency analysis. In the future, it is needed to develop the practical approximated procedure to UNCODE.

• Korean Journal of Computational Design and Engineering
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• v.16 no.1
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• pp.61-72
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• 2011

As the customer's needs for diverse colors, the process of bus painting shop is becoming more and more complex. In particular, frequent changes of paint colors in each spray process require the cleaning of the painting nozzles and setting them up for the new paints, which results in increased time and cost and reduced production. This also increases environmental influences. This paper proposes, as a solution to this issue, the use of color selection field (CSF). CSF is physically a system of conveyors that are used to rearrange objects in a flow line. CSF is proposed, in this paper, to be introduced right before the spray process so that buses are better grouped according to their desired colors. Various parameters of the CSF, such as the number of conveyors and algorithms to determine the rearranged sequence of buses, have been determined by running simulations using the digital manufacturing technology, and investigating the simulation results. As an outcome of the proposed solution, the CSF system is expected to reduce approximately 30% of the nozzle cleaning cost for a Korean motor company case, which will not only benefit the company economically, but will also benefit the environment.

• The Research Journal of the Costume Culture
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• v.24 no.2
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• pp.218-232
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• 2016

The purpose of this study was to investigate the differences in various fashion lifestyle segments' perceived benefits and design preferences for outdoor clothing to improve the development of outdoor clothing. Data were collected by questionnaire from 600 subjects aged 30 years and over with experience purchasing outdoor clothing in the past year. Frequency analysis, factor analysis, cluster analysis, reliability analysis, ANOVA, and chi-square analysis were used for the data analysis. The results of this study were as follows. Four segments were identified based on fashion lifestyle: manifoldly conscious, sensation conscious, practicality conscious, and brand conscious. Perceived outdoor clothing benefits generated three dimensions, including premium brand, practicality, and functionality, and preferred image produced two factors, tasteful/refined and comfortable/casual. Significant differences were found in the purpose of purchasing outdoor clothing, perceived benefit, and image and t-shirt pattern design preference among the segments. The manifoldly conscious group had a higher tendency to pursue various benefits and images of outdoor clothing and to prefer t-shirt textile designs with foulards and stripes. The sensation conscious group considered fashion and individuality in daily life but not in outdoor clothing. The practicality conscious group showed a preference for simple and casual styles with functionality and foulard patterns for t-shirts. The brand conscious group tended to prefer a striking design to functionality. This study is expected to be used as preliminary data for merchandising planning of outdoor clothing.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.4
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• pp.181-188
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• 2010

The objectives of this study are to analyze the possibility of the landfill gas recycling for the middle and small scale landfills where the recycling facilities are not installed in Korea. It was found that the power generation plants by landfill gas were installed in domestic 15 landfills and the gas engine generation was adopted in 14 places. As the result of economic analysis, the landfill gas recycling is found to be available in 12 places and CERs of 153,693 $tCO_{2e}$ can be secured per year. Through the reduction of the air pollutants and VOCs, the social benefits of 730 million won accrue per year. Also, the power production of 18.8 GWh will substitute the crude oil imports of 4,048 TOE and the revenue of 2.49 billion won is expected to power trading. It is also found that the power generation plants by landfill gas will give the social benefits such as the reduction of the environmental problems and the substitution effect of crude oil imports.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.3
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• pp.114-125
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• 2004

On the assumption that marketing is a useful technique to activate park use, this study aims to find what benefits people pursue and how much they attain them through a park visit. To achieve this, the survey of a Benefits-Sought for a park was conducted at four major parks in the city of Taejon and an Importance-Performance Analysis(IPA) was conducted. Additionally, a Present Condition survey was performed with the park managers. As a result, first, it was found that major benefits are a comfortable rest, an escape from bustling city life, to see natural scenery and to promote physical health, and so forth. Second, performance was relatively lower than importance in the case of recreation and leisure activities, which means that facilities should be improved and programs for park use should be developed. Third, at GaYang park, importance and performance are good in balance. DongChunDang park and Seattle park have 5 items and 7 items for which immediate improvements are required. Saemmeury park generally shows good proportions and it can be much activated by improving the learning and experiencing activities. The results objectively show conditions of neighborhood parks in the city of Taejon from a view of park users. Therefore, it is expected that the results would be useful in determining priorities when improving park facilities or their programs.

• The Journal of Information Technology
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• v.9 no.3
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• pp.15-25
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• 2006

Currently there is fast flow of America and South Korea FTA negotiation being issued. Aim of FTA, by having free trade between two countries to gain their economical benefit. Few benefits can be expected by Korea joining FTA with America It will increase export as well as increase in overseas investment and this will lead to booming of services industry. After America and Korea FTA Discussion being announced around the world, Australia and EU also has interest of doing FTA with South Korea, which mean that America and Korea FTA has effect of bring in the overseas interest of FTA to South Korea. Expectation of American can be, create the market in South Korea to gain benefit as well as able to check out the economical issue of north east Asia country such as China and Japan. Since American side has high agreement with the make FTA with South Korea, South Korea now has to make own decision about this matter. Since Korean economy highly influence by world trade, to survive from market competition with China and Japan, Korea must involve in Free trade with world.

• Korean System Dynamics Review
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• v.14 no.3
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• pp.105-134
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• 2013

Electrical construction business has public and professional characters. It may require appropriate interventions of the government because these business activities stand for not only profit-seeking competition, but also supplies of one of the key functions in our society. In other words, public benefit and private benefit are still in existence. The government therefore considers such an aspect of public importance of the business sector and needs to plan to adjust technical and engineering manpower of this market. This study focuses on the imbalance for labor supply and demand of technical engineer in electrical construction business. A system dynamics analysis is applied to understand and simulate the imbalance as a soft approach. It has the merit of causal loop diagram to alleviate the limitation of data lack problem. We find that excess demand is expected from 2010 to 2011, and excess supply is predicted from 2012 to 2021 about the manpower of technical engineer. It shows considerable disagreement between the supply and demand of human resource. So we suggest that it is strong necessity to construct statistics infrastructure for a manpower supply and demand plan.

• Journal of Energy Engineering
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• v.10 no.3
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• pp.177-182
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• 2001

This paper aims at evaluating HSDI diesel passenger cars introduction. The result of economic analysis after accounting for the life cycle cost per car shows a saving of 13,836 thousand won in fuel cost per diesel car assuming a life of 10 years and the annual travel distance of 20,000km. Assuming an average travel distance of 20,000km and a 10% increase in sales of diesel passenger car, the social benefit starts to accrue from the year 2002 and, in 2010, is estimated to be 154.1 billion won relative to the gasoline passenger car. The cumulative social benefit up to 2010 under the same assumptions is expected to reach 636.8 billion won.

• KEPCO Journal on Electric Power and Energy
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• v.1 no.1
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• pp.67-71
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• 2015

The concept known as Vehicle-to-Grid (V2G) is to provide power to help balance loads by charging at night when demand is low and sending power to the grid when demand is high. Therefore, it is important to model the cost-benefit characteristics of Electric vehicle(EV)'s operation considering the negawatt market in real time. This paper proposes a methodology to formulate the various costs and economic benefits for sending the EV's power back to the grid, including a concept of inconvenience costs caused by operating the EV as a battery. This paper also introduces the general decision-making process based on the cost-benefit analysis in order to simulate the reasonable participation of V2G service. In the case study, it is confirmed by two-case simulations that the proposed approach is useful to help EV owners' decision-making. In the future, it is expected that the proposed methodology can be used as a decision-making guideline to help prepare the EV' power transmission.