• ETRI Journal
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• v.45 no.4
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• pp.627-635
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• 2023

In vehicular edge computing (VEC) networks, the rapid expansion of intelligent transportation and the corresponding enormous numbers of tasks bring stringent requirements on timely task offloading. However, many tasks typically appear within a short period rather than arriving simultaneously, which makes it difficult to realize effective and efficient resource scheduling. In addition, some key information about tasks could be learned due to the regular data collection and uploading processes of sensors, which may contribute to developing effective offloading strategies. Thus, in this paper, we propose a model that considers the deterministic demand of multiple tasks. It is possible to generate effective resource reservations or early preparation decisions in offloading strategies if some feature information of the deterministic demand can be obtained in advance. We formulate our scenario as a 0-1 programming problem to minimize the average delay of tasks and transform it into a convex form. Finally, we proposed an efficient optimal offloading algorithm that uses the interior point method. Simulation results demonstrate that the proposed algorithm has great advantages in optimizing offloading utility.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.37
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• pp.111-115
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• 1996

This study is to decide each level ordering policy for deterministic demand in multilevel distribution system. The ordering policy is used the combinations of EOQ and LTC. The combinations of EOQ and LTC are 4 cases. Case 1 : Regional Warehouse∼EOQ, Central Warehouse∼EOQ. Case 2 : Regional Warehouse∼EOQ, Central Warehouse∼LTC. Case 3 : Regional Warehouse∼LTC, Central Warehouse∼EOQ. Case4 : Regional Warehouse∼LTC, Central Warehouse∼LTC. The criterion is to minimize total cost per year.

• The Journal of the Korea Contents Association
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• v.7 no.10
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• pp.165-174
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• 2007

It is expected that demand for cultural industry will be increased rapidly with economic growth. But it is doubtful how much desire of demander to be fulfilled. Because cultural products have public goods characteristics and they are supplied by government. Therefore this paper analysed deterministic factors of cultural demands in Chung-buk province, and suggested criteria of cultural products, which is supplied by regional government. For these purposes, we analysed three topics, first, deterministic factors of demander's satisfaction, second deterministic factors of cultural demand type, which are classified by type of participants and spectators, third deterministic factors of leisure type, which are classified by goods intensive leisure and time intensive leisure, and we analysed these through econometric methods. And we tried to suggest optimal criteria for cultural products supply by regional government, which needs of demanders are fully fulfilled.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.4
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• pp.559-569
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• 1998

Cellular manufacturing system (CMS) has been recognized as an alternative to improve manufacturing productivity in conventional batch-type manufacturing systems through reducing set-up times, work-in-process inventories and throughput times by means of group technology. Most of the studies on the design of CMS assumed that each part has a unique process plan, and that its demand is known as a deterministic value despite of the probabilistic nature of the real world problems. This study suggests an approach for designing CMS, considering both alternative process plans and uncertain demand. A mathematical model is presented to show how to minimize the expected amortized and operating costs satisfying these two relaxations. Four heuristic algorithms are developed based on tabu search which is well suited for getting an optimal or near-optimal solution. Example problems are carried out to illustrate the heuristic algorithms and each of them is compared with the deterministic counterpart.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.3
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• pp.194-200
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• 2005

A stochastic dynamic lot sizing problem for multi-item is suggested in the case that the distribution of the cumulative demand is known over finite planning horizons and all unsatisfied demand is fully backlogged. Each item is produced simultaneously at a variable ratio of input resources employed whenever setup is incurred. A dynamic programming algorithm is proposed to find the optimal production policy, which resembles the Wagner-Whitin algorithm for the deterministic case problem but with some additional feasibility constraints.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.3
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• pp.81-91
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• 1994

This paper is to build an economic production quantity model for situations, in which, during the stockout period, a fraction .betha.(backorder ratio) of the demand is backordered and remaining fraction (1-.betha.) is lost. This paper develops an objective function representing the average annual cost of a production system by defining a time-weighted backorder cost and a lost sales penalty cost per unit lost under the assumptions of deterministic demand rate and deterministic production rate, and provides an algorithm for its optimal solution. At the extreme .betha.= 1, the presented model reduces to the Fabrycky's model with complete backorders.

• Journal of the Korean Operations Research and Management Science Society
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• v.5 no.1
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• pp.53-59
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• 1980

An order level inventory model is developed for deteriorating items. The demand during prescribed scheduling period is constant and deterministic in which the demand follows power pattern. Deterioration is assumed to be a constant fraction of the on hand inventory. The expression for the optimal order level is developed and an example is given to illustrate the model.

• Management Science and Financial Engineering
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• v.18 no.1
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• pp.21-26
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• 2012

Two previous studies that attempted to generalize the deterministic joint pricing-inventory decision model are reevaluated. We prove analytically that even in a single-product environment, the EOQ model with constant priceelastic demand cannot find optimal solutions unless two optimality conditions associated with price elasticity and demand magnitude are satisfied. Due to the inexistence of the general optimality for the problem, demand function and price elasticity must be evaluated and bounded properly to use the methods proposed in the previous studies.

• Journal of the Korean Operations Research and Management Science Society
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• v.33 no.1
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• pp.1-17
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• 2008

Market segmentation is a key strategic factor in increasing the expected profits, especially in the practice of revenue management. A manufacturing firm should manage both manufacturing quantities and pricing decisions over its segmented markets to maximize the expected profits, setting different price for each different segment. Also, market segments should be kept separate in order to prevent demand leakages between different market segments. In fact, even though the markets for different products are firmly segmented, it is not easy to keep separate segmentation because many products might be substitutable by customer buying behavior. That is, customers respond to price changes by purchasing other market's products instead of purchasing the originally requested products, which causes demand substitution effect ; This kind of substitution is referred to as price-driven substitution. Therefore, decisions on optimal prices should take into account the differences in customers' valuation of the different products. We consider a deterministic model for deciding optimal prices in the presence of price-driven substitution, and we compare both symmetrical-and asymmetrical-type demand substitutions between two segmented markets. The objective of this study is to develop analytical and numerical models to examine the impact of price-driven substitution on the optimal price levels and the total expected profits.

• Journal of the Korea Safety Management & Science
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• v.11 no.1
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• pp.205-211
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• 2009

In reality, distribution planning for a supply chain is established using a certain probabilistic distribution estimated by forecasting. However, in general, the demands used for an actual distribution planning are of deterministic value, a single value for each of periods. Because of this reason the final result of a planning has to be a single value for each period. Unfortunately, it is very difficult to estimate a single value due to the inherent uncertainty in the probabilistic distribution of customer demand. The issue addressed in this paper is the selection of single demand value among of the distributed demand estimations for a period to be used in the distribution planning. This paper proposes an efficient demand selection scheme for minimizing total inventory costs while satisfying target service level under the various experimental conditions.