• 정보처리학회논문지C
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• 제11C권7호
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• pp.937-950
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• 2004

본 논문에서는 프로토콜 조합 및 서비스 참조 기법을 지원하는 Customizable Architecture for Flexible Execution Environment(CAFEs) 실행환경을 실제 및 구현한다. CAFEs 실행환경은 프로토콜 및 서비스 소프트웨어의 재사용성을 높이기 위하여 기존 프로토콜의 기능 또는 알고리즘을 구현한 마이크로 프로토콜과 기존 응용과 호환하고 액티브 네트워크 서비스를 배포하기 위한 수단으로 동작하는 액티브 서비스라는 새로운 개념을 제시한다. 제안된 액티브 네트워크 실행환경은 기능에 따라 세 부분으로 설계되어 있다. 첫째, 가상 네트워크 시스템은 기존의 다양한 프로토콜 계층을 기반으로 가상 네트워크 채널을 형성하고 이를 바탕으로 액티브 노드를 연결한다. 둘째, 프로토콜 및 서비스 관리자는 마이크로 프로토콜 및 액티브 서비스를 합성함으로써 새로운 프로토콜과 서비스를 제공하는 역할을 담당한다. 마지막으로 이벤트 엔진은 이벤트 위임 모델을 사용하여 서비스에 존재하는 컴보넌트의 상태전이를 자동으로 감지한다. 그리고 개발된 CAFEs 실행환경을 검증하기 위하여 무선 인터넷 환경에서 사용자 단말에 적합한 웹 컨텐츠를 전달하기 위한 실험을 수행하여 가용성을 확보하였다.

• Journal of Electrical Engineering and Technology
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• 제4권3호
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• pp.315-322
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• 2009

Penetration and installation of a new dynamic technology known as Flexible AC Transmission Systems (FACTS) in a practical and dynamic network requires and force expert engineer to develop robust and flexible strategy for planning and control. Unified Power Flow Controller (UPFC) is one of the recent and effective FACTS devices designed for multi control operation to enhance the power system security. This paper presents a dynamic strategy based on Particle Swarm Optimization (PSO) for optimal parameters setting of UPFC to enhance the system loadability. Firstly, we perform a multi power flow analysis with load incrementation to construct a global database to determine the initial efficient bounds associated to active power and reactive power target vector. Secondly a PSO technique applied to search the new parameters setting of the UPFC within the initial new active power and reactive power target bounds. The proposed approach is implemented with Matlab program and verified with IEEE 30-Bus test network. The results show that the proposed approach can converge to the near optimum solution with accuracy, and confirm that flexible multi-control of this device coordinated with efficient location enhance the system security of power system by eliminating the overloaded lines and the bus voltage violation.

• 한국항행학회논문지
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• 제19권6호
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• pp.595-600
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• 2015

전통적인 midway 광 위상 공액기 (OPC; optical phase conjugator)가 아닌 non-midway OPC를 분산 제어 (DM; dispersion-managed) 광전송 링크에 적용하여 파장 분할 다중 전송 (WDM; wavelength division multiplexed)을 위한 융통적인 네트워크의 구성 가능성을 분석하였다. 중계 구간의 수가 많을수록, 또한 중계 구간 당 잉여 분산 (RDPS; residual dispersion per span)이 클수록 non-midway OPC를 통한 유연한 링크의 구성 가능성이 커지는 것을 확인하였다. 아울러 OPC 이후의 후반 전송 구획을 구성하는 각 중계 구간의 RDPS를 OPC 이전의 전반 구획의 RDPS의 평균값으로 설정하는 링크 구조가 융통적 링크 구성에 더욱 유리하다는 것을 확인하였다.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.193-203
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• 2012

This study analyzed regular transportation costs between port warehouses and processing plants and between processing plants and central distribution centers and further transportation costs relations according to empty transfer rates in each circulation by examining the distribution routes of imported grain including wheat, barley, corn, and soybean, namely port warehouses, processing plants, and central distribution centers. Based on the results, the study compared and reviewed the logistics transportation costs. The analysis results of the alternative model show that logistics operational costs could be considerably cut down by introducing a flexible vehicle transportation operational method, which is to change the vehicle loading parts for proper substitute transportation after unloading and transport them to other locations such as central distribution centers instead of returning empty, as an alternative to high operational costs deriving from empty vehicle operation in each circulation after unloading items in case of transportation of imported grain and processed items. The results allow for a more realistic approach to general problems with large-scale distribution network operation and provide a theoretical foundation to serve as a guide to establish policies for corporate operation of imported grain logistics systems.

• 한국경영과학회지
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• 제23권4호
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• pp.75-86
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• 1998

We address the problem of determining the optimal processing times and pallet/fixture allocation in Flexible Manufacturing systems in order to minimize tool cost while meeting throughput targets of multiple part types. The problem is formulated as a nonlinear program superimposed on a closed queueing network of the FMSs under consideration. A numerical example reveals the potential of our approach for significant cost saving. We argue that our model can be Integrated Into the process planning system of an FMS to generate efficient process plans quickly.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.721-724
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• 1994

This paper proposes a continuous hitting by a flexible link hammer. This hammer system is used only the first mode of vibration for a desired hitting. The input of the hammer driver for a continuous hitting is obtained from numerical solutions of two sets of non-linear simultaneous equations which satisfy the hitting conditions. Being too complicated, these numerical calculations are not useful for online processing. Therefore, the multi-layered neural networks are applied to the generation of the input patterns of the hammer driver. The trained network outputs agree well to the numerical solutions.

• 산업경영시스템학회지
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• 제23권61호
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• pp.13-22
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• 2000

To apply the queueing network theory in evaluating performances of flexible manufacturing systems, it is generally assumed that the processing times are distributed exponentially. However, in FMS, processing times are usually deterministic. In this study the performance measures of FMS are approximated under the assumption that processing times are usually deterministic. Multi-classes of parts and single server and multi-server stations are considered in the model. This study also that, in the numerical example, this approach yields better solutions than those obtained by the pure Linearizer algorithm, when the processing times are deterministic.

• 산업경영시스템학회지
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• 제24권67호
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• pp.19-26
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• 2001

A design issue for a flexible manufacturing system is to find the number of each resource type which assures a given production ratio with a minimal cost. The FMS is modeled as a closed queueing network with a local buffer of limited capacity. An efficient method to determine this optical configuration is presented. The proposed method consists of three steps : 1) determine a lower configuration, 2) derive a heuristic solution, 3) find the optimal solution. The derived heuristic solutions are close to the optical solution.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1281-1285
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• 2004

There are numerous emotions in the human world. Human expresses and recognizes their emotion using various channels. The example is an eye, nose and mouse. Particularly, in the emotion recognition from facial expression they can perform the very flexible and robust emotion recognition because of utilization of various channels. Hybrid-feature extraction algorithm is based on this human process. It uses the geometrical feature extraction and the color distributed histogram. And then, through the independently parallel learning of the neural-network, input emotion is classified. Also, for the natural classification of the emotion, advancing two-dimensional emotion space is introduced and used in this paper. Advancing twodimensional emotion space performs a flexible and smooth classification of emotion.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.711-716
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• 2003

This study considers the implementation issues of the inter-vehicle communication system for the vehicle platoon experiments via a testbed. The testbed, which consists of three scale vehicles and one RCS(remote control station), is developed as a tool for functions evaluation between simulation studies and full-sized vehicle researches in the previous study. The cooperative communication of the vehicle-to-vehicle or the vehicle-to-roadside plays a key role for keeping the relative spacing of vehicles small in a vehicle platoon. The static platoon control, where the number of vehicles remains constant, is sufficient for the information to be transmitted in the suitably fixed interval, while the dynamic platoon control such as merge or split requires more flexible network architecture for the dynamical coordination of the communication sequence. In this study, the wireless communication device and the reliable protocol of the flexible network architecture are implemented for our testbed, using the low-cost, ISM band transceiver and the 8-bit microcontroller.