• 한국경영과학회지
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• 제37권1호
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• pp.1-18
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• 2012

The present study provides some extensions over a recent work in Won (2011) which investigates properties of the static newsvendor problem under a schedule involving progressive multiple discounts under the assumption that demand is given exogenously. Khouja (1995, 1996) formulated the extended versions over the classical newsvendor model with various discount policies including all-units discount and/or multiple discounts and found that the extended newsvendor models with discount schedules yield higher optimal expected profits than the classical newsvendor model with no-discounts. In this study, we establish a robust conjecture as a stronger statement than Khouja's findings with regard to the general relationship among the expected profits of newsvendor models in the sense that the conjecture holds for every order quantity as well as the optimal order quantity. The conjecture encourages the newsvendor facing quantity discounts to safely implement her own discounts policy to customer or accept quantity discounts offered by the supplier even if the optimal order quantity cannot be ordered due to additional restrictions such as budget or warehouse capacity constraints because the newsvendor models with quantity discounts always yield higher expected profit than the classic newsvendor model without quantity discounts regardless of the order quantity. Results from wide experiments with various probability distributions of demand strongly support our conjecture.

• Management Science and Financial Engineering
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• 제18권2호
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• pp.23-27
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• 2012

The problem of jointly determining a robust optimal bundle of price and order quantity for a retailer in a single-retailer, single supplier, single-product supply chain is considered. Demand is modeled as a decreasing power function of product price, and unit purchasing cost is modeled as a decreasing power function of order quantity and demand. Parameters defining the two power functions are uncertain but their possible values are characterized by ellipsoids. We extend a previous study in two ways; the purchasing cost function is generalized to take into account the economies of scale realized by higher product demand in addition to larger order quantity, and an exact transformation into an equivalent convex optimization program is developed instead of a geometric programming approximation scheme proposed in the previous study.

• 한국산학기술학회논문지
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• 제14권10호
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• pp.4812-4818
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• 2013

본 논문은 한국의 식용 천일염 수요 및 공급 규모를 예측한 내용을 담고 있다. 2007년 염관리법 규정에 의해 식용으로 허용된 천일염은 그 이전에는 광물로 분류되어있었기 때문에 식용 천일염 관련 별도의 연도별 통계자료가 정비되어 있지 않은 실정이다. 최근 식용 천일염에 대한 소비자 수요증대와 더불어, 산업계에서 시장규모 파악 및 그 성장가능성에 대한 관심이 높다. 이 연구는 식용 천일염 수급 추정을 위한 관련 자료가 제한적인 상황에서 생산을 위한 기후여건, 생산업체 현황, 소비추세, 수출입 동향 등을 고려하여 식용 천일염 수요 및 공급규모를 예측하였다. 연구결과, 2013-2017년 동안 생산량은 222-384천 톤 수준, 수입량은 498-565천 톤, 수출량은 2.67-3.62천 톤, 소비량은 767-996천 톤 수준에 이를 것으로 예측되었다.

• 한국산림과학회지
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• 제98권3호
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• pp.311-318
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• 2009

본 연구는 GIS를 이용하여 산림 바이오 에너지에 대한 공급 및 수요의 잠재량을 파악하고, 잠재지도 제작을 목적으로 하였다. 산림이 많고, 지리적으로 같은 위치에 해당하는 강원도 영동 지방 4개 시군(고성군, 양양군, 강릉시, 삼척시)을 연구 지역으로 선정하였으며, 수치 임상도의 임상과 영급정보, 통계연보의 가구수 정보를 GIS 자료 형태로 전환한 후 산림 바이오에너지의 잠재된 공급량과 수요량을 파악하였다. 숲가꾸기사업 계획을 기초로 가구수를 고려한 수요대비 잠재적 공급가능량은 약 3,144 Tcal로써, 시군단위에 상관없이 초과공급이 가능한 것으로 나타났으나, 강원도의 평균 수집률인 10%를 고려하면, 시의 경우 6%, 군은 15% 공급 가능한 것으로 나타났다. 한편, 수집률 변화에 따른 공급가능성을 비교한 결과, 60% 이상인 경우, 초과공급이 가능한 지역이 발생하였다.

• 자원ㆍ환경경제연구
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• 제9권2호
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• pp.311-332
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• 2000

The main aim of this paper is to estimate the change in the quantity demanded of public water when the economic factors such as income and water price are changed. The privious methods to estimate the quantity of public water demanded has been usually based on the LPCD(liter per capita per day). Implicitly, this method regards the price of water as given. If the water price and income elasticities of water demand are estimated using the time-series and pooled data analysis. In the second step, the quantity demanded of public water are forecasted using the estimated elasticities. The results show that we can reduce the quantity demanded of residential water considerably when the water price is changed.

• 품질경영학회지
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• 제40권4호
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• pp.441-452
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• 2012

Purpose: In this paper, we have considered a problem of newsvendor model in an environment of random yields in quality and customer balking behavior, in which only the mean and the variance of the demand are known. In practice, the distributional information of the demand is very limited and only the mean and variance are guessed by experience. In addition, due to the customers balking behavior occurring when the available inventory level decreases, the product's demand becomes a function of inventory level so that the classical newsvendor's optimal order quantity is no longer optimal. Methods: We have developed an optimal order quantity model that enables us to incorporate the random yield of a product and the customer balking information such as a threshold inventory level of balking and the corresponding probability of a sale during the balking. Results: We illustrated the concepts developed here through simple numerical examples and showed the robustness of our model in a various setting of parameters. Conclusion: This paper provides a useful analysis showing that our distribution-specific and distribution-free approach to the optimal order quantity in the newsboy model can act as an effective tools to match supply with demand for these product lines.

• KIEE International Transactions on Power Engineering
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• 제5A권4호
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• pp.403-411
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• 2005

At present, the Cournot model is one of the most commonly used theories to analyze the gaming situation in an oligopoly type market. However, several problems exist in the successful application of this model to the electricity market. The representative one is obtaining the inverse demand curve able to be induced from the relationship between market price and demand response. In the Cournot model, each player offers their generation quantity to obtain maximum profit, which is accomplished by reducing their quantity compared with available total capacity. As stated above, to obtain the probable Cournot equilibrium to reflect the real market situation, we have to induce the correct demand function first of all. Usually the correlation between price and demand appears over the long-term through statistical data analysis (for example, regression analysis) or by investigating consumer utility functions of several consumer groups classified as residential, industrial, and commercial. However, the elasticity has a tendency to change continuously according to the total market demand size or the level of market price. Therefore it should be updated as the trading period passes by. In this paper we propose a method for inducing and updating this price elasticity of demand function for more realistic market equilibrium.

• 전기학회논문지
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• 제59권9호
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• pp.1658-1662
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• 2010

This paper presents an advanced energy saving algorithm in building. It is important to aggregate a various demand side resource which is surely controllable at the peak power time to reduce the energy cost. Previous demand side algorithm appropriate for building is based on peak power. In this paper, we develop the new energy saving algorithm to reduce the quantity of power consumption. The simulation results show that the proposed tem is very effective.

• 한국항만경제학회지
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• 제37권1호
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• pp.71-85
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• 2021

기업이 물류비용을 절감할 수 있는 정교한 수요 예측 모형은 그동안 수많은 연구를 통해 다양한 방법들이 제시되었다. 이러한 연구들은 주로 수요 패턴에 의해서 적용 가능한 수요 예측 모형을 결정하고, 통계적 검증을 통해서 모형의 정확성을 판단하였다. 수요 패턴은 크게 규칙성과 불규칙성으로 나뉘어 질 수 있다. 규칙적인 패턴은 주문이 정기적이고 주문량이 일정한 경우를 의미한다. 이러한 경우에는 주로 회귀모형이나 시계열 모형을 통해서 수요를 예측하는 방법들이 사용된다. 그러나 불규칙적이고 주문량의 변동 폭이 큰 경우는 간헐적 수요(Intermittent Demand)라고 하는데, 기존의 회귀 모형이나 시계열 모형으로는 수요 예측의 오류 발생 가능성이 높기 때문이다. 간헐적 수요를 보이는 품목에 대해서는 주로 Croston모형 혹은 Holts모형 등을 사용하여 수요를 예측한다. 본 연구에서는 간헐적 수요 패턴을 보이는 항공 화물의 다양한 품목에 대해서 수요 패턴을 분석하고, 다양한 모형을 통해 수요를 예측하여 각 모형의 예측력을 비교 분석하였다. 이 과정에서 항공 화물의 품목별, 지역별로 다양한 모형의 적합도를 분석하여 항공사가 가장 효율적으로 운영할 수 있는 항공 화물의 수요 예측 모형에 대한 개발 방향을 제시하고자 함이 본 논문의 목적이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.168-170
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• 2005

At present Cournot model is one of the most commonly used theories to analyze the gaming situation in oligopoly market. But there exist several problems to apply this model to electricity market. The representative one is to obtain the inverse demand curve able to be induced from the relationship between market price and demand response. In Cournot model, each player offers their generation quantity to accomplish maximum profit, which is accomplished by reducing their quantity compared with available total capacity. As stated above, to obtain the probable Cournot equilibrium to reflect real market situation, we have to induce the correct demand function first of all. Usually the correlation between price and demand appears on the long-term basis through the statistical data analysis (for example, regression analysis) or by investigating consumer utility functions of several consumer groups classified as residential, industrial, and commercial. However, the elasticity has a tendency to change continuously according to the total market demand size or the level of market price. Therefore it should be updated as trading period passes by. In this paper we propose a method for inducing and updating this price elasticity of demand function for more realistic market equilibrium