• Title/Summary/Keyword: Flexible Network

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An Active Network Execution Environment for on Demand Customization of Communication Protocols and Services (맞춤형 통신 프로토콜과 서비스를 위한 액티브 네트워크 실행환경)

  • Lee Hwa Young;Kang Bo-young;Lim Kyungshik
    • The KIPS Transactions:PartC
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    • v.11C no.7 s.96
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    • pp.937-950
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    • 2004
  • In this paper, we present the design and implementation of new execution environment named Customizable Architecture for Flexible Execution Environment(CAFEs) that supports the mechanism of protocol customization and service referencing. We introduce a new concept as micro protocols and active services to enhance software reusability. Micro protocol represents a specific algorithm or functionality of existing network protocol and the active service is in charge of binding legacy application and releasing the active network oriented services. The pro-posed active network execution environment is made up of three parts, virtual network system, protocol and service manager, event engine. First, the virtual network system is used to connect each active nodes using virtual network channels which are based on multiple existing protocol layers. Second, the protocol and service manager is responsible for composing micro protocols and active services to develop new network proto-col and service easily. Finally, the event engine is used to detect the automatic transition of system components using event delegation model. To verify the CAFTs, we have an experiment about the delivery of web contents which are suitable for the user's terminals in the wireless Internet environment. As a result. we are able to obtain the availability of developed execution environment.

Strategy based PSO for Dynamic Control of UPFC to Enhance Power System Security

  • Mahdad, Belkacem;Bouktir, T.;Srairi, K.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.3
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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.

Compensation for the Distorted WDM Channels through the Dispersion-managed Optical Links with Non-midway Optical Phase Conjugator (Non-midway 광 위상 공액기를 갖는 분산 제어 전송 링크를 통한 WDM 채널의 왜곡 보상)

  • Lee, Seong-Real
    • Journal of Advanced Navigation Technology
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    • v.19 no.6
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    • pp.595-600
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    • 2015
  • The implementation possibility of the flexible optical network configuration using the non-midway optical phase conjugator (OPC) in the dispersion-managed (DM) optical link for wavelength division multiplexed (WDM) transmission is demonstrated in this paper. It is confirmed that the implementation possibility of flexible link configuration is more increased, as number of fiber spans is more bigger and the residual dispersion per span (RDPS) is more large. It is also confirmed that the non-midway OPC link, in which RDPS of the latter half transmission section (after OPC) is decided by the averaged RDPS of the former half transmission section (before OPC), has more advantage for the flexible network configuration.

A Study on the Effects of Flexible Operation of Imported Grain Transportation Vehicles on Logistics Costs by Considering Empty Transfer Rates (공차율을 고려한 유연한 수입곡물 화물차운영이 물류비용에 미치는 영향에 관한 연구)

  • Kim, Byeong Chan;Yang, Dae Yong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.4
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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.

Saving Tool Cost in Flexible Manufacturing Systems: Joint Optimization of Processing Times and Pallet Allocation (유연생산시스템에서 절삭공구 비용절감을 위한 가공시간과 팔렛배분의 최적화)

  • 김정섭
    • Journal of the Korean Operations Research and Management Science Society
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    • v.23 no.4
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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.

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Continuous hitting by a flexible link hammer with neural networks generating input pattern

  • Hitaka, Yoshikazu;Izumi, Teruyuki
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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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.

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A study on the Performance Evaluation of Flexible Manufacturing Systems (유연생산시스템의 성능평가에 관한 연구)

  • 장진익;김원중
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.61
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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.

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A Determination on Optimal Configuration of Flexible Manufacturing System (유연생산시스템의 최적구성 결정)

  • 장진익;김원중
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.24 no.67
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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.

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Hybrid-Feature Extraction for the Facial Emotion Recognition

  • Byun, Kwang-Sub;Park, Chang-Hyun;Sim, Kwee-Bo;Jeong, In-Cheol;Ham, Ho-Sang
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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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.

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Implementation of Inter-vehicle Communication System and Experiments of Longitudinal Vehicle Platoon Control via a Testbed

  • Kim, Tae-Min;Choi, Jae-Weon
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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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.

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