• Journal of Institute of Control, Robotics and Systems
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• v.13 no.5
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• pp.422-428
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• 2007

This paper presents a neural network based adaptive control approach to a reconfigurable flight control law that keeps handling qualities in the presence of faults or failures to the control surfaces of an aircraft. This approach removes the need for system identification for control reallocation after a failure and the need for an accurate aerodynamic database for flight control design, thereby reducing the cost and time required to develope a reconfigurable flight controller. Neural networks address the problem caused by uncertainties in modeling an aircraft and pseudo control hedging deals with the nonlinearity in actuators and the reconfiguration of a flight controller. The effect of the reconfigurable flight control law is illustrated in results of a nonlinear simulation of an unmanned aerial vehicle Durumi-II.

• Journal of Industrial Technology
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• v.22 no.B
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• pp.79-88
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• 2002

This paper deals with a case study on the process improvement and the layout design of a boiler factory with FactoryCAD. Firstly, two alternatives of job reallocation are suggested with the understanding of problems in current process. The layout planning for these new alternatives is carried out by simple procedure and the detailed analyses are performed by the aid of FactoryCAD program. The result shows that the new layout plan brings on about 10% reduction of travel distance. The utilization of FactoryCAD program can simplify the process of layout design.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.76-81
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• 2002

The purpose of this study is to set up the optimum economical formation of the purse seiner fishing system. For this task, the characteristics of existing purse-seiner fishing system were reviewed, and the possible formations of the fleet in tile purse-seiner fishing system were examined through the reallocation of function for each individual vessel. In addition, economic evaluations of the possible formations of the fleet are carried out. Consequently, it was found that 2-vessel formations have the most economic efficiency. Then, a conceptual system design for the main vessel in the 2-vessel formations was performed. As a result, this paper can be used as a helpful guideline to develop the most profitable and economical fishing system in the fleet type fishery.

• KDI Journal of Economic Policy
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• v.37 no.4
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• pp.55-74
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• 2015

Using the Census on Establishments collected by Statistics Korea, we analyze how the patterns of job creation and destruction differ across counties (si-gun-gu). We measure aggregate employment changes due to establishment startups, expansions, contractions, and shutdowns for each county and quantify the role of such reallocations in explaining variation in employment growth across counties. Overall we find that both rates of net entry and job creation play an important role in explaining differences in net job creation rates across regions. Moreover, counties with high employment growth rates also tend to have high exit and job destruction rates, which suggests that an active process of job reallocation is a key source of regional employment growth.

• Journal of Communications and Networks
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• v.16 no.5
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• pp.559-567
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• 2014

In this paper, a framework for power allocation of downlink transmissions in orthogonal frequency division multiple access-based decode-and-forward cellular relay networks is investigated. We consider a system with a single base station communicating with multiple users assisted by multiple relays. The relays have limited power which must be divided among the users they support in order to maximize the data rate of the whole network. Advanced power allocation schemes are crucial for such networks. The optimal relay power allocation which maximizes the data rate is proposed as an upper bound, by finding the optimal power requirement for each user based on knapsack problem formulation. Then by considering the fairness, a new relay power allocation scheme, called weighted-based scheme, is proposed. Finally, an efficient power reallocation scheme is proposed to efficiently utilize the power and improve the data rate of the network. Simulation results demonstrate that the proposed power allocation schemes can significantly improve the data rate of the network compared to the traditional scheme.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.200-202
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• 1999

This paper describes the optimization problem of real power rescheduling and present an algorithm based linear programming for studying the load-shedding and generation reallocation problem when a portion of the transmission system is disabled and at power flow solution cannot be obtained for the overload of some lines. And in case initial is infeasible, solution could not be converge. So this paper gives an algorithm being lie infeasible quantities within limit. The paper describes a LP-based algorithm to obtain the solution in power dispatch related to overload situations in power system and it is easily extened under various objective. The optimization procedures is based in linear programming with bounded variables and use the multi-segment curve method for a objective function and the validity of the algorithm is verified with two examples : 10-bus system and 57-bus system.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.5
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• pp.113-120
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• 2013

This paper presents a mathematical model to determine the optimal length of static messages that can achieve more efficient use of a FlexRay network. In order to determine the optimal length of static message, the proposed model evaluates the given set of messages with respect to a network utilization index, which is defined in this work. The efficient use of a FlexRay network is achieved by reallocating any static message whose length is equal or greater than the resulting value to the dynamic segment. The effectiveness of the proposed method is investigated by applying to the SAE benchmark data.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2005.11a
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• pp.3-7
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• 2005

본 논문에서는 방송에 사용되는 주파수 이용 현황을 조사, 분석하였다. 주파수 이용 기본 정비 방안과 세부추진 방안을 분석하여 바람직한 활용방안을 제시하였다. 주파수 할당을 위한 경매 제도를 분석하여 DTV의 스펙트럼의 재활용 방안으로서의 적합성을 검토하였다. DTV의 리턴채널 가능성도 분석하였다. 분석한 결과를 토대로 3가지 활용방안을 제시하고 각 방안의 장단점도 언급하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.85-87
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• 2001

다수의 이익-추구형 에이전트들 간의 자동화된 협상 과정을 통해 합리적으로 작업 분배가 이루어질 수 있도록 조정하는 것은 대부분의 다중 에이전트 시스템에서 매우 중요한 문제이다. 본 연구에서는 대표적인 다중 에이전트 작업 재할당 문제의 하나로서 다중 에이전트 외판원 여행 문제를 설명하고, 이 문제를 풀기 위한 조정 메커니즘으로 Vickrey 경매 프로토콜의 적용을 제안하였다. 대표적인 시장기반의 조정 메커니즘인 Vickrey 경매의 적용을 위해 본 논문에서는 각 에이전트의 이익, 협상의 최종 목표, 경매대상, 각 에이전트의 입찰전략, 전체적인 경매 진행과정 등을 정의하였다. 이와 같이 설계된 시장기반의 조정메커니즘의 장점은 각 에이전트의 이익만을 고려함으로써 문제를 단순화할 수 있고, 복잡도가 큰 중앙-집중식 제어 메커니즘이 필요치 않으며, 따라서 각 에이전트의 자율성을 최대한 보장할 수 있고, 큰 협상비용을 들이지 않고 최적의 할당에 도달할 수 있다는 점등이다. 본 논문에서는 하나의 다중 에이전트 외판원 여행문제에 대한 풀이과정을 통해 앞서 설계된 Vickrey 경매프로토콜의 진행방식을 설명하고 그 효과와 효율성을 예시하였다.

• Journal of Families and Better Life
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• v.19 no.2
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• pp.83-96
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• 2001

This study examined housework time management strategies between married female home-based workers and on-site workers, and found out the factors affecting the housework time management strategies. The data were collected from 165 married female home-based workers, and 292 married female on-site workers in Pusan and Kyungnam province, by self-administered questionnaire. Frequency distributions, Cronbachs alpha, t-tests, Pearsons correlations, and multiple regression analyses were conducted by SPSS/PC+. The major findings of this study were kas follows: 1) Married female home-based workers more used obtaining additional help and personal time reallocation than married female on-site workers. 2) For married female home-based workers, educational attainment and occupation were significant factors affecting housework time management strategies, and for married female on-site workers, employment hours per week and existence of elders/disability within the family were important variables.