• Bulletin of the Korean Space Science Society
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• 2007.10a
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• pp.135-138
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• 2007

The present work is to estimate the stability region of the State-Dependent Riccati Equation (SDRE) controlled system, which is used for a decentralized coordinated attitude control in satellite formation flying. In this research, currently emerging methods which estimate region of attraction for the SDRE controllers are introduced and the methods are applied to attitude control systems. The results guarantee the stability of the given decentralized coordinated attitude control system in satellite formation flying.

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1116-1127
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• 2016

• Korean Management Science Review
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• v.19 no.1
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• pp.107-116
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• 2002

A major challenge to supply chain managers is how to control inventories and costs along the supply chain while maximizing customer service Performance. In the literature, although the optimal management of inventory along the supply chain has received considerable attention during the past decades, the attention has been mainly given to multi-echelon control policies. A prerequisite for applying these policies is full information transparency in the supply chain, which is hard to accomplish in practice because it may require major organizational chanties. In the case that a decentralized control (local (R, S) policy) should be used at each location in multi-stave distribution systems, this paper presents the coordinating approach of determining the best policy which satisfies predetermined target customer service levels and minimizes the mean physical stock along the system.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.5
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• pp.530-537
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• 2009

A graphic simulator can be a useful tool for planning gaits or dynamic behaviors to a walking pet robot. Microsoft describes robotics developer studio (MSRDS) as an end-to-end robotics development platform including simulation engine based on dynamics. In this paper, we propose a pet robot simulator (PRS), based on MSRDS, which supports interactively controlled two walking robots connected over network. To be pet robot simulator, modeling a commercial pet robot is performed and gait planning is also implemented. By using concurrency and coordination runtime (CCR) and decentralized software services (DSS) of MSRDS software platform, we connect two robots which are displayed together but controlled separately over network. The two walking pet robots can be simulated interactively by joysticks. It seems to be an internet game for pet robots.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.3
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• pp.17-39
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• 2005

The coordination of a three-level supply chain consisting of a supplier, a retailer, and a discount outlet (DCO) is studied here. We assume that the product is sold in two consecutive periods a Normal Sales Period (NSP) and a subsequent Clearance Salvage Period (CSP). A benchmark case is studied Initially in which the supply chain is coordinated by a s1n91e agent. Thus, the supplier the retailer, and the discount outlet design a common system that allows centralized decision making about stocking quantities, markdown time schedules, and policies on disposing of leftovers to deliver the greatest possible expected supply chain profit. Next, we consider a decentralized supply chain. Here, decisions are made without coordination. The objective is to maximize an individual party's expected profits. The focus of the study is on the following questions: what factors make the coordination an effective approach for the supply chain? How do we coordinate the supply chain so as to maximize the supply chain Joint expected profit? These and other related study issues are explored in this paper.

• Journal of Communications and Networks
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• v.14 no.6
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• pp.662-671
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• 2012

Plug-in hybrid electric vehicles (PHEVs) will be widely used in future transportation systems to reduce oil fuel consumption. Therefore, the electrical energy demand will be increased due to the charging of a large number of vehicles. Without intelligent control strategies, the charging process can easily overload the electricity grid at peak hours. In this paper, we consider a smart charging and discharging process for multiple PHEVs in a building's garage to optimize the energy consumption profile of the building. We formulate a centralized optimization problem in which the building controller or planner aims to minimize the square Euclidean distance between the instantaneous energy demand and the average demand of the building by controlling the charging and discharging schedules of PHEVs (or 'users'). The PHEVs' batteries will be charged during low-demand periods and discharged during high-demand periods in order to reduce the peak load of the building. In a decentralized system, we design an energy cost-sharing model and apply a non-cooperative approach to formulate an energy charging and discharging scheduling game, in which the players are the users, their strategies are the battery charging and discharging schedules, and the utility function of each user is defined as the negative total energy payment to the building. Based on the game theory setup, we also propose a distributed algorithm in which each PHEV independently selects its best strategy to maximize the utility function. The PHEVs update the building planner with their energy charging and discharging schedules. We also show that the PHEV owners will have an incentive to participate in the energy charging and discharging game. Simulation results verify that the proposed distributed algorithm will minimize the peak load and the total energy cost simultaneously.