• 물과 미래
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• 제27권4호
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• pp.135-143
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• 1994

본 연구에서는 상수도 급수량의 시간적 변화형태를 조사하고, 수요량의 시간적인 변화량에 통계학적 개념을 이용하여 수요량의 시간적 변화에 관한 확률적 분산모형에 관하여 검정 결정하였다. 연구대상의 지역으로 광주시를 선정하고, 자료로는 2시간 간격으로 측정된 배수지의 수위와 1일 상수도 생산량을 이용하였다. 급수계통의 모형에 통제용적과 연속방정식을 적용하여 2시간별로 변화되는 수요량을 결정하고, 매월 단위로 정리하여 수요수량의 변화를 알 수 있도록 하였다. 2시간별 수요수량은 1일 총 급수량에 대한 백분율로 환산하여 지수화하였으며, 시간별로 변화되는 각각의 급수량은 통계학적으로 추론될 수 있는지 알 수 있도록 분산모형에 관하여 검정을 하였다. 검정결과를 이용하면 시간별 확률 급수량의 산정이나 급수량의 통계학적 해석을 통하여 상수도 시설의 운용에 이용할 수 있는 것으로 판단되었다.

• 토지주택연구
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• 제9권3호
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• pp.9-18
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• 2018

Administrative city has been developed step by step aiming to being a public transport-oriented new city. In spite of its primary goal, administrative city is dominated by car-oriented tansportaion system because the supply of public transportation has not been adequately and timely performed. In this study, we investigate the current situation related to (public) transportation use in administrative city. Also, we examine the issues of traffic system through a survey on residents' consciousness about public transportation use. Additionally, the analysis of demand elasticity according to the change of the conditions of using public transportation and passenger car is conducted for passenger car users. As a result, it is analyzed that as the neighborhood is more stabilized after the completion of development the resistance to the abandonment of passenger car is higher when the tide demand control method is introduced. Therefore, it is concluded that pre-emptive public transportation supply and the management of car demand management are necessary for the activation of public transportation in Administrative city.

• 대한안전경영과학회지
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• 제12권4호
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• pp.255-263
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• 2010

The research developes short-run standardized control charts(SSCC) and short-run acceptance control charts(SACC) under the various demand patterns. The demand patterns considered in this paper are three types such as high-variety and repetitive low-volume pattern, extremely-high-variety and nonrepetitive low-volume pattern, and high-variety and extremely-low-volume pattern. The short-run standardized control charts developed by extending the long-run ${\bar{x}}$-R, ${\bar{x}}$-s and I-MR charts have strengths for practioners to understand and use easily. Moreover, the short-range acceptance control charts developed in the study can be efficiently used through combining the functions of the inspection and control chart. The weighting schemes such as Shewhart, moving average (MA) and exponentially weighted moving average (EWMA) can be considered by the reliability of data sets. The two types according to the use of control chart are presented in the short-range standardized charts and acceptance control charts. Finally, process capability index(PCI) and process performance index(PPI) classified by the demand patterns are presented.

• 한국태양에너지학회 논문집
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• 제39권5호
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• pp.29-40
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• 2019

In response to the rapid climate change, in order to save energy in the field of buildings, the country is planning not only zero energy buildings but also zero energy cities. In the Urban Development Project, the Energy Use Plan Report is prepared and submitted by predicting the amount of energy demand at the planning stage. However, due to the activation of zero-energy buildings and the increase in the supply of new and renewable energy facilities, the energy consumption behavior of buildings in the city is changing from the previous ones. In this study, to estimate urban energy demand of Zero Energy City, building energy demand forecasts based on "Passive plans for use of energy based primary energy consumption", "Actual building energy usage data from Korea Appraisal Board" and "data from Certification of Building Energy Efficiency Rating" as well as demand forecast according to existing "Consultation about Energy Use Plan Code" were calculated and then applied to Multifunctional Administrative City 5-1 zone to compare urban total energy demand forecasts.

• 경영과학
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• 제29권1호
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• pp.101-114
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• 2012

The demand for naval spare parts is intermittent and erratic. This feature, referred to as non-normal demand, makes forecasting difficult. Hierarchical forecasting using an aggregated time series can be more reliable to predict non-normal demand than direct forecasting. In practice the performance of hierarchical forecasting is not always superior to direct forecasting. The relative performance of the alternative forecasting methods depends on the demand features. This paper analyses the influence of the demand features on the performance of the alternative forecasting methods that use hierarchical and direct forecasting. Among various demand features variability, kurtosis, skewness and equipment groups are shown to significantly influence on the performance of the alternative forecasting methods.

• ETRI Journal
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• 제7권3호
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• pp.35-41
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• 1985

The objective of this study is to estimate the price elasticity of demand for telephone use in Korea. This paper provides a comprehensive review of the existing empirical study and establishes the econometric demand estimation model applicable to Korean telephone service. By this model, the price elasticities of demand in local and toll uses are estimated and their implications are discussed.

• 한국ITS학회 논문지
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• 제15권4호
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• pp.1-11
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• 2016

본 연구는 카셰어링의 대중교통 접근성이 카셰어링 이용수요에 미치는 영향을 분석하는 것을 목적으로 한다. 이를 위해 수원시에서 운영 중에 있는 그린카의 대여이력 데이터베이스와 대중교통 GIS DB를 활용하여 카셰어링 대여소별로 대중교통 접근성에 따른 카셰어링 이용수요 모형을 구축하고 이를 해석하였다. 연구 결과 카셰어링 대여소로의 접근수단은 도보가 73%로 가장 많으며, 자전거 3%, 버스와 도시철도는 20%로 나타났다. 버스와 도시철도의 접근성이 반영된 카셰어링 이용 모형의 적합도는 0.818로 대중교통 접근성은 유의한 변수임을 확인하였다. 즉, 카셰어링의 대여소는 대중교통과의 환승이 용이한 장소에 설치되는 것이 보다 이용수요를 증진시킬 수 있음을 확인하였다. 특히 대중교통 수단 중 버스 접근성은 유의한 변수로 확인된 반면, 도시철도 접근성은 유의하지 않은 것으로 나타났는데, 타 대중교통 수단과의 상호 이용수요 증진 측면에서 도시철도와 카셰어링간의 원활한 연계를 위한 환승할인 및 편도 반납 정책 등 다양한 보완적 정책이 필요할 것으로 판단된다. 본 연구 결과는 카셰어링에 대한 기초적 연구에 불과하지만, 대중교통간 환승수요를 증진시키는데 기여할 것으로 기대된다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.833-836
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• 2012

최대수요전력 관리 장치는 현재 사용전력을 모니터링하여 예측 전력을 계산해 수용가에서 설정한 목표전력을 초과하지 않게 부하를 제어하는 장치이다. 부하의 제어는 예측된 최대수요전력이 목표전력을 초과할 경우 경보를 발생하고 부하를 차단하는 방식을 사용하기 때문에 최대수요전력에 대한 정확한 예측이 중요하다. 전력 변동이 심한 수용가에서는 기존의 예측 방법을 사용할 경우 최대수요전력 관리가 안정적이지 못하다는 단점이 있다. 본 논문에서는 기존의 최대수요전력 예측 방법 및 지수평활방법을 살펴보고 칼만 필터를 사용한 예측 방법을 제안한다.

• 농촌계획
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• 제14권3호
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• pp.37-51
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• 2008

This study aims to build a model dealing with the location decision of new manufacturing firms and their land demand. The model is composed with 1) the binary logit model structure identifying a future probability of manufacturing firms to locate in a city and their land demand; and 2) the land use suitability of the land demand. The model was empirically tested in the case of Anseong City. We used establishment-level data for the manufacturing industry from the Report on Mining and Manufacturing Survey. 48 industry groups were scrutinized to find the location probability in the city and their land demand via logit model with the dependent variables: number of employment, land capital, building capital, total products, and value-added for a new industry since 2001. It is forecasted that the future land areas (to 2025) for the manufacturing industries in the city are $5.94km^2$ and additional land demand for clustering the existing industries scattered over the city is $2.lkm^2$. Five industrial complex locations were identified through the land use suitability analysis.

• 수산경영론집
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• 제48권2호
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• pp.19-32
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• 2017

The purpose of this study is to identify problems and suggest improvements of estimating procedures and item of fisheries supply-demand statistics served as a basis for the fisheries supply-demand policies. Korea Rural Economic Institute(KREI) and Ministry of Oceans and Fisheries(MOF) respectively publish the fisheries supply-demand statistics. But the reliability of data is low as the statistics of these two organizations are limited and show discrepancy in the numbers. It is therefore difficult to use them as the basic data for policies. Also, an accurate data aggregation is difficult due to following problems in the items of statistics. 1) Problems in estimating route sales and non-route sales of production, 2) adequacy of fishery product yield rate compared to raw material in the fisheries import/export sector, 3) selection of target companies for understand stocks and survey scope of fish species, 4) applying'0'to non-edible product demand etc. In order to develop the fisheries industry as a future growth industry, it is necessary to establish the accurate fisheries supply-demand policy as the instability of fisheries supply and demand is increasing. To do this, statistical reliability has to be improved. The improvements proposed in this study should be implemented considering urgency. First of all, an exhaustive analysis of stock statistics and conversion rates of raw material yield in the fisheries import/export sector should be conducted. In the medium term and the long term, transferring production statistics to MOF and surveys on the use demand of non-food product and the level of reduced and discarded seafood products should be carried out in consecutive order.