• 대한산업공학회지
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• 제20권4호
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• pp.135-149
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• 1994

Demand forecasting is to estimate the demand of customers for products and services. Since the future is uncertain in nature, it is too difficult for us to predict exactly what will happen. Therefore, when the forecasting is performed upon the uncertain future, it is realistic to estimate the value of demand as an interval or a fuzzy number instead of a crisp number. In this paper, we propose a demand forecasting method using the standard back-propagation algorithm and then we extend the method to the case of interval inputs. Next, we demonstrate that the proposed method using the interval neural networks can represent the fuzziness of forecasting values as intervals. Last, we propose a demand forecasting method using the transformed input variables that can be obtained by taking account of the degree of influence between an input and an output.

• 전기학회논문지
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• 제65권7호
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• pp.1128-1134
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• 2016

Demand response provides customer load reductions based on high market prices or system reliability conditions. One type of demand response, price-based program, induces customers to respond to changes in product rates. However, there are large-scale general and industrial customers that have difficulty changing their energy consumption patterns, even with rate changes, due to their electricity demands being commercial and industrial. This study proposes an in-house pricing model for large-scale general and industrial customers, particularly those with multiple business facilities, for self-regulating demand-side management and cost reduction. The in-house pricing model charges higher rates to customers with lower load factors by employing peak to off-peak ratios in order to reduce maximum demand at each facility. The proposed scheme has been applied to real world and its benefits are demonstrated through an example.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.156-156
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• 2022

Explicitly spatially distributed and reliable data on industrial water demand is very much important for both policy makers and researchers in order to carry a region-specific analysis of water resources management. However, such type of data remains scarce particularly in underdeveloped and developing countries. Current research is limited in using different spatially available socio-economic, climate data and geographical data from different sources in accordance to predict industrial water demand at finer resolution. This study proposes a random forest regression (RFR) model to predict the industrial water demand at 0.50× 0.50 spatial resolution by combining various features extracted from multiple data sources. The dataset used here include National Polar-orbiting Partnership (NPP)/Visible Infrared Imaging Radiometer Suite (VIIRS) night-time light (NTL), Global Power Plant database, AQUASTAT country-wise industrial water use data, Elevation data, Gross Domestic Product (GDP), Road density, Crop land, Population, Precipitation, Temperature, and Aridity. Compared with traditional regression algorithms, RF shows the advantages of high prediction accuracy, not requiring assumptions of a prior probability distribution, and the capacity to analyses variable importance. The final RF model was fitted using the parameter settings of ntree = 300 and mtry = 2. As a result, determinate coefficients value of 0.547 is achieved. The variable importance of the independent variables e.g. night light data, elevation data, GDP and population data used in the training purpose of RF model plays the major role in predicting the industrial water demand.

• 산업경영시스템학회지
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• 제28권2호
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• pp.146-151
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• 2005

Some distributions have been used for diagnosing the lead time demand distribution in inventory system. In this paper, we describe the negative binomial distribution as a suitable demand distribution for a specific retail inventory management application. We here assume that customer order sizes are described by the Poisson distribution with the random parameter following a gamma distribution. This implies in turn that the negative binomial distribution is obtained by mixing the mean of the Poisson distribution with a gamma distribution. The purpose of this paper is to give an interpretation of the negative binomial demand process by considering the sources of variability in the unknown Poisson parameter. Such variability comes from the unknown demand rate and the unknown lead time interval.

• 산업경영시스템학회지
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• 제28권4호
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• pp.79-84
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• 2005

Some distributions have been used for diagnosing the lead time demand distribution in inventory system. In this paper, we describe the negative binomial distribution as a suitable demand distribution for a specific retail inventory management application. We here assume that customer order sizes are described by the Poisson distribution with the random parameter following a gamma distribution. This implies in turn that the negative binomial distribution is obtained by mixing the mean of the Poisson distribution with a gamma distribution. The purpose of this paper is to give an interpretation of the negative binomial demand process by considering the sources of variability in the unknown Poisson parameter. Such variability comes from the unknown demand rate and the unknown lead time interval.

• 자원ㆍ환경경제연구
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• 제14권2호
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• pp.475-491
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• 2005

공업용수 수요량 예측방법으로 현재 사용되고 있는 부지면적원단위법의 문제점을 분석하고 이에 대한 대안으로 수요함수를 이용하는 방법을 분석한다. 실제 조사 자료인 산업 총조사보고서의 자료와 비교하면 최근의 공업용수 수요량은 부지면적 원단법의 수요량 예측치보다는 본 연구에서 사용한 수요함수를 이용하여 추정한 수요량 예측치가 훨씬 더 정확하게 추정되었음을 보여준다. 그리고 가격 변화에 따른 수요량 변화 효과가 상당함을 보이고 있으므로 공업용수 수요량 관리를 위한 가격정책의 유효성을 보여준다. 따라서 향후 공업용수 수요량 추정에서는 부지면적원단위법보다는 용수 가격 및 산출량 등 경제적인 변수를 고려한 수요함수를 이용하는 것이 바람직하다.

• 대한산업공학회지
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• 제35권3호
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• pp.203-212
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• 2009

The bullwhip effect refers to the phenomenon where demand variability is amplified when one moves upward a supply chain. In this paper, we exactly quantify the bullwhip effect for cases of seasonal demand processes in a two-echelon supply chain with a single retailer and a single supplier. In most of the previous research, some measures of performance for the bullwhip effect are developed for cases of non-seasonal demand processes. The retailer performs demand forecast with a multiplicative seasonal mixed model by using the minimum mean square error forecasting technique and employs a base stock policy. With the developed bullwhip effect measure, we investigate the impact of seasonal factor on the bullwhip effect. Then, we prove that seasonal factor plays an important role on the occurrence of the bullwhip effect.

• 대한산업공학회지
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• 제33권4호
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• pp.439-446
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• 2007

A new location model, where the demand varies by periods, and the facility at each period can be open or closed depending on the demand, is discussed in this paper. General facility location problem is extended with the assumption that demands per period vary. A mixed integer programming is suggested and the solution is found for various instances which are randomly generated. Instances included various cases with respect to the length of periods, moving distance of customer locations, and cost structure. The characteristics of optimal solutions are analyzed for various cases, and it is shown that demand changing location model can be applied in a practical fields of supply chains.

• 산업경영시스템학회지
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• 제22권49호
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• pp.67-76
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• 1999

This research presents the relationship among machining time, cycle time and demand rate in a cellular manufacturing system. The manufacturing cell produces part families by automated machines. This paper discusses the cases of increasing demand rate in an existing cell and designing cell based on the demand rate. This research developed an algorithm for decision making such as cycle time, machines and workers in order to minimize the total machine capacity and the number of workers for any given demand rate. The proposed algorithm was successfully applied for the design and operation of cell manufacturing with a good result.

• 산업공학
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• 제16권4호
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• pp.400-410
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• 2003

Most of the demand forecasting which have been studied is about long-term time series over 15 years demand forecasting. In this paper, we set up the most optimal ARIMA model for the short-term time series demand forecasting and suggest demand forecasting system for short-term time series by appraising suitability and predictability. We are going to use the univariate ARIMA model in parallel with the bivariate transfer function model to improve the accuracy of forecasting. We also analyze the effect of advertisement cost, scale of branch stores, and number of clerk on the establishment of marketing policy by applying statistical methods. After then we are going to show you customer's needs, which are number of buying products. We have applied this method to forecast the annual sales of refrigerator in four branch stores of A company.