• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.73-78
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• 2008

This paper predicts the future power demands of Gaesung industrial complex. Power flow and voltage dynamics are shown and an efficient method for supplying the electric power to Gaesung industrial complex is proposed.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.339-340
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• 2015

본 연구의 목적은 우리나라의 소방력을 효율적으로 배치하기 위해 전문가를 중심으로 설문조사를 실시하여 우리나라의 환경과 수요에 부합하는 소방력 배치기준의 핵심요소를 파악하기 위함이다. 설문조사는 소방력 배치기준 핵심요소들의 객관적인 비교결과를 제시하기 위하여 델파이 기법을 활용하였다. 연구결과를 종합해 볼 때, 우리나라의 소방력배치는 관할면적과 관할인구에 기초한 단순배치에 머물고 있다. 국내 소방력 배치의 문제점을 개선하기 위해서는 소방환경과 소방수요, 소방력과 관련된 다양한 변수들을 반영할 수 있는 새로운 소방력 배치기준을 마련해야 하며, 시 도별 지자체의 환경에 따른 소방력 배치가 이루어져야 할 것으로 사료된다.

• Annual Conference of KIPS
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• 2000.04a
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• pp.715-718
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• 2000

본 논문은 WDM 광 통신망에서 망의 효율적인 설계에 필요한 알고리즘에 관한 것이다. WDM 광 통신망은 경로설정 및 파장할당이 중요한 변수로 s-d 노드 쌍간에 필요한 연결수요가 주어질 때 이 연결수요를 만족시켜주는 광 경로를 설정하고, 파장을 할당해 줌으로써 사용 파장수를 최소화하면서 파장을 재사용 할 수 있는 효율을 최대로 하는 것이 목적이다. WDM 방식을 이용하여 전기적 변환에 따른 지연 없이 전광통신망에서 여러 개의 파장을 다중화하여 동시에 자료를 전송함으로서 수Gbps, 혹은 그이상의 전송이 가능해질 것으로 기대되어 진다. 이들 설계 문제들은 일반적인 토폴로지 망에서 정적인 경로 설정 및 파장할당을 대상으로 하여 발견적인 알고리즘을 얻고자 하였다. 또한 이를 통해 LP모형으로 얻은 하한 한계 값과 휴리스틱 알고리즘의 최소파장수와 동일한 값이 나올 수 있는 알고리즘을 구하였다.

• Korean Journal of Construction Engineering and Management
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• v.6 no.3 s.25
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• pp.144-155
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• 2005

Since 1950s, the Korean housing market has continually experienced the chronicle lack of housing stock because of lower housing investment in comparison with a population explosion, prompt urbanization and rapid restructuring of family. The Korean housing market have thus been driven not by the pricing model by housing demand-supply chain but by the Korean housing policies focusing on the increase of housing supply and the living stability of the middle or low-income bracket. After all, repetitive economic vicious circle of housing price and the increase of unsold apartments aggravated the malfunction of the Korean housing market. Meanwhile, the Korean construction firms have exacerbated their profitability. Such terrible situations are mainly triggered by the Korean construction firms that weighed on the short-term profits and quick response of the government policy alterations rather than the prospect of housing market Therefore, this research focusing on the dynamics of housing market identified and classified the demand and supply elements that consist not only of housing system structures but also of the environmental elements that affect the structures. Based on the system thinking and traditional theory of consumer's choice, the interactions of these elements were constructed as a causal loop diagram that explains the mutual influences among housing subsystems with feedback loops. This paper describes and discusses about the causes of the dynamic changes in the Korean housing market. This study would help housing suppliers, including housing developers, construction firms, etc., to form a more comprehensive understanding on the fundamental issues that constitute the Korean housing market and thereby increasing their long term as well as minimizing the risk involved in the housing supply businesses.

• Journal of Korea Technology Innovation Society
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• v.19 no.3
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• pp.511-544
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• 2016

Standards boost technological innovation by promoting information sharing, compatibility, stability and quality. Identifying groups of companies that particularly benefit from these functions of standards in their technological innovation and commercialization helps to customize planning and implementation of standards-related policies for demand groups. For this purpose, this study engages in profiling of SMEs whose R&D objective is to respond to standards as well as those who need to implement standards system for technological commercialization. Then it suggests a prediction model that can distinguish such companies from others. To this end, decision tree analysis is conducted for profiling of characteristics of subject SMEs through data mining. Subject SMEs include (1) those that engage in R&D to respond to standards (Group1) or (2) those in need of product standard or technological certification policies for commercialization purposes (Group 2). Then the study proposes a prediction model that can distinguish Groups 1 and 2 from others based on several variables by adopting discriminant analysis. The practicality of discriminant formula is statistically verified. The study suggests that Group 1 companies are distinguished in variables such as time spent on R&D planning, KoreanStandardIndustryClassification (KSIC) category, number of employees and novelty of technologies. Profiling result of Group 2 companies suggests that they are differentiated in variables such as KSIC category, major clients of the companies, time spent on R&D and ability to test and verify their technologies. The prediction model proposed herein is designed based on the outcomes of profiling and discriminant analysis. Its purpose is to serve in the planning or implementation processes of standards-related policies through providing objective information on companies in need of relevant support and thereby to enhance overall success rate of standards-related projects.

• Environmental and Resource Economics Review
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• v.24 no.4
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• pp.747-761
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• 2015

This paper investigates the impact of an increase in unit price of solid waste collection on demand for alternative solid waste disposal types. I control for other variables affecting the demand and employ both community and time fixed effects models in the estimation of each reduced-form demand functions. Estimation results show that an increase in unit price reduces the demand for garbage bag collection services of non-food solid wastes while it increases the demand for food wastes and source-separated recyclables. These results imply that reduction in the demand for non-food solid wastes collection is mainly achieved by increasing the amount of recyclables and food wastes collected. However, it appears that an increase in unit price increases the total amount of solid wastes generated. This suggests that price incentive effects are offset by the decrease in source-reduction efforts because of feedback effects resulting from the increase in recycling, food waste separation, and illegal disposal of wastes.

• Journal of Korean Society of Transportation
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• v.29 no.1
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• pp.17-27
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• 2011

This paper investigates some critical errors influencing travel demand estimation in Korea Transportation Data Base (KTDB), and through this investigation reasonable traffic analysis zone (TAZ) size and internal trips ratio are analyzed. With varying zone size, the accuracy of travel demand estimation is studied and appropriate level of zone size in KTDB is also presented. For this purpose zonal structure consisting of location of zone centroid, number of centroid connecters has been constructed by social economic index, and then some descriptive statistical analyses such as F-test, coefficient of correlation are performed. From the results, this paper shows that the optimum levels of zone system were various according to the order and capacity of roads, and also shows that the smaller TAZ, the less error in this research. In conclusion, in order to improve accuracy of traffic demand estimation it is necessary to make zone size smaller.

• Korea Real Estate Review
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• v.24 no.1
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• pp.27-37
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• 2014

Recently increasing the supply of housing policy has not been able to reflect social phenomena as like decreasing birth rate, aging of the population and increasing 1 or 2 person households. This study analyze the housing demand in the city with the point of population growth rate and economic character changes. Growing cities have positive population growth rate and economic character, but shrinking cities have the opposite. By comparing housing demand of growing cities and shrinking cities, we want to find out housing policy implications. In this study, results suggest that the peak age of housing demand of shrinking cities is the late 60's. But the growing cities's age peak is the mid-80's. But further analysis of the economic variables and 1 or 2 person old and young household dummies, the result is that the peak age of housing demand is reduced. These results suggest that housing demand should be differentiated the cities's population structure and economic characteristics of the household. In short, housing demand will vary depending on the condition of individual cities.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1522-1526
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• 2007

최근 영국의 Institute of Hydrology에서는 Generalized logistic (GL) 분포형을 홍수빈도해석시 GEV 분포형을 대체하는 분포형으로 추천한 바 있으며, 그로 인해 GL 분포형의 사용이 증가하고 있는 추세이다. 하지만 아직 그 사용빈도에 반하여 분포형 자체의 특성, 그 중에서도 확률홍수량의 근사적 분산에 관한 연구는 거의 이루어지지 않았다. 따라서 본 연구에서는 최우도법을 이용하여 GL 분포형의 확률홍수량에 대한 근사적 분산에 관한 연구를 수행하였으며, 이를 표본 크기, 재현기간, 매개변수들의 함수로 나타내었다. 또한 확률홍수량의 근사적 분산의 적용성을 검토하기 위해 Monte Carlo 모의실험을 수행하였으며, 모의실험은 형상 매개변수$(\beta)$가 $\pm0.5$이면 gamma function으로 인하여 표본 크기에 관계없이 분산값이 무한대에 가까워지므로 형상매개변수의 범위는 $-0.5{\leq}{\beta}{\leq}+0.5$로 제한하였다. 모의결과 최우도법에 의해 계산된 분산식은 형상매개변수 $-0.25{\leq}{\beta}{\leq}+0.5$의 범위에서 비교적 잘 맞는 것을 확인할 수 있었으며, 기존에 알려진 대로 표본크기가 크면 클수록 정확해지는 것을 알 수 있다. 또한 표본크기가 작은 경우 형상매개변수 전 범위에서 정확도가 떨어지는 것을 확인할 수 있으며, 최우도법의 경우 표본크기가 작은 경우를 제외하고 $-0.25{\leq}{\beta}{\leq}+0.5$ 범위에서 quantile 산정시 quantile이 약간 과다추정되는 경향이 있는 것을 알 수 있으며, 이는 분산이 과다 추정되는 결과를 초래하며 이로 인해 해석해보다 약간씩 큰 값을 나타내는 것으로 판단되었다..이 극단적인 선정적인 폭력성에 탐닉하게 되는 경향이 있다. 현실은 결코 아름답지 못하고, 행복하게 살 수 없다는 것에 대한 깨달음에서 기인한다. 욕구불만의 강도가 심해질수록 폭력성은 더욱 강하게 나타나는데 개인에게서 뿐만 아니라 가족, 동료, 사회 단체나 종교, 국가간에도 집단적으로도 발생하게 된다. 사회적으로 볼 때 폭력은 용인되는 것이 아니므로 도덕적으로 절제를 하거나 상대방과 적절한 타협과 조정을 필요로 한다. 그러나 절제의 한계를 넘어선다고 생각되거나, 조정의 노력이 불가능하거나, 실패했을 때 폭력적인 행동으로 나타나게 된다. 리차즈(I.A Richards)는 분노와 공포는 일단 겉잡을 수 없는 경향이 있다고 하면서 오늘날 폭력에 대한 요구가 일상의 정서 생활에 있어, 억압을 통한, 빈곤함을 반영하고 있지 않은지 생각해봐야 할 것이라고 충고한다. 조성 가이드라인(안)을 제시하였다.EX>$\ulcorner$세종실록$\lrcorner$(世宗實錄) $\ulcorner$지리지$\lrcorner$(地理志)와의 비교를 해보면 상 중 하품의 통합 9개소가 삭제되어 있고, $\ulcorner$동국여지승람$\lrcorner$(東國與地勝覽) 에서는 자기소와 도기소의 위치가 완전히 삭제되어 있다. 이러한 현상은 첫째, 15세기 중엽 경제적 태평과 함께 백자의 수요 생산이 증가하자 군신의 변별(辨別)과 사치를 이유로 강력하게 규제하여 백자의 확대와 발전에 걸림돌이 되었다. 둘째, 동기(銅器)의 대체품으로 자기를 만들어 충당해야할 강제성 당위성 상실로 인한 자기수요 감소를 초래하였을 것으로 사료된다. 셋째, 경기도 광주에서 백자관요가 운영되었으므로 지방인 상주지역에도 더 이상 백자를 조달받을 필요가 없이, 일반 지방관아와 서민들의

• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.332-342
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• 2012

The current research aims at classifying the bus stops as transfer center in order to establish the rational bus transfer systems. Existing research typically identifies characteristics of demands for bus stops and land use surrounding the bus stops and classifies and profiles the bus stops. A common problem with this type of research is that the results with cross-sectional characteristics of land use and bus stop usage do not capture the details of trip chain, the fundamental characteristics of the trips with transfer. This paper therefore examines bus stop classifications with such variables as transport mode chains, intermediate stop chains and timing chains. The analysis on the data collected on Monday 20 April 2009 for passengers of Gyeong-gi bus results in a clear classification among bus stops in terms of such trip chain variables. The research would provide useful information for the decision support of transfer stops location choice and infrastructure design.