• 제목/요약/키워드: Performance engineering

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A Study on the Planning Technique of High-rised Housing Estates Applying Smart Green City Concept : Focus on Multi-functional Administrative City 2-1 Neighborhood (스마트 그린시티 개념을 적용한 고층주거단지 계획기법에 관한 연구 : 행정중심복합도시 2-1생활권을 중심으로)

  • Lee, Seo-Jeong;Lee, Eung-Hyun;Oh, Deog-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.379-387
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    • 2016
  • The goal of this research is to identify the planning techniques of high-rise housing estates applying a smart green city concept in order to understand the necessity of integrating 'planning & building' planning techniques and 'smart system' planning techniques and to analyze the current status of application. For the research, firstl, the definition of smart green city was established and high-rise housing estates planning was categorized according to a three space hierarchy, seven planning directions and 17 major features through literature review. Second, 28 'planning & building' planning techniques and 'smart system' planning techniques were derived through literature review and FGI analysis. Last, four cases in Multi-functional Administrative City were analyzed for the current status of application of planning techniques. In conclusion, planning techniques in 'Transportation Network', 'Environment-friendly layout planning of housing', 'Revitalization of green transportation', 'Utilization of new & renewable energy', 'Crime prevention and accident reduction', 'Use of high performance, and efficiency facility' main feature were identified as important planning techniques for Smart Green City and its implications were estimated.

A Basic Study on Sorting of Black Plastics of Waste Electrical and Electronic Equipment (WEEE) (폐가전의 검정색 플라스틱 재질선별에 관한 기초 연구)

  • Park, Eun Kyu;Jung, Bam Bit;Choi, Woo Zin;Oh, Sung Kwun
    • Resources Recycling
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    • v.26 no.1
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    • pp.69-77
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    • 2017
  • Used small household appliances(small e-waste) consists of a variety of complex materials and components. The small e-waste is mainly composed of plastics and an important potential source of waste plastic. The black plastics, particularly are very difficult to separate by resin type and therefore these are mainly recycled in the form of a mixtures. In the present study, the sorting technologies such as gravity and electro static separation, near-infrared ray(NIR) and IR/Raman optical sorting separation on mixture of black plastics were analyzed and their limitations on sorting process were also investigated. The Laser Induced Breakdown Spectroscopy(LIBS) spectrum of each black plastics was used for identification of black plastics by resin type, and after analyzing the normalization operation, Principal Component Analysis(PCA) was carried out. The spectrum data was optimized through PCA process. In order to improve the identification accuracy and sorting efficiency of black plastics, it is necessary to design a classifier with high efficiency and to improve the performance and reliability of the classifier by applying the field of intelligent algorithms.

Localization of Unmanned Ground Vehicle based on Matching of Ortho-edge Images of 3D Range Data and DSM (3차원 거리정보와 DSM의 정사윤곽선 영상 정합을 이용한 무인이동로봇의 위치인식)

  • Park, Soon-Yong;Choi, Sung-In
    • KIPS Transactions on Software and Data Engineering
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    • v.1 no.1
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    • pp.43-54
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    • 2012
  • This paper presents a new localization technique of an UGV(Unmanned Ground Vehicle) by matching ortho-edge images generated from a DSM (Digital Surface Map) which represents the 3D geometric information of an outdoor navigation environment and 3D range data which is obtained from a LIDAR (Light Detection and Ranging) sensor mounted at the UGV. Recent UGV localization techniques mostly try to combine positioning sensors such as GPS (Global Positioning System), IMU (Inertial Measurement Unit), and LIDAR. Especially, ICP (Iterative Closest Point)-based geometric registration techniques have been developed for UGV localization. However, the ICP-based geometric registration techniques are subject to fail to register 3D range data between LIDAR and DSM because the sensing directions of the two data are too different. In this paper, we introduce and match ortho-edge images between two different sensor data, 3D LIDAR and DSM, for the localization of the UGV. Details of new techniques to generating and matching ortho-edge images between LIDAR and DSM are presented which are followed by experimental results from four different navigation paths. The performance of the proposed technique is compared to a conventional ICP-based technique.

CMF-based Priority Processing Method for Multi-dimensional Data Skyline Query Processing in Sensor Networks (센서 네트워크에서 다차원 데이터 스카이라인 질의 처리를 위한 CMF 기반의 우선처리 기법)

  • Kim, Jin-Whan;Lee, Kwang-Mo
    • KIPS Transactions on Software and Data Engineering
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    • v.1 no.1
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    • pp.7-18
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    • 2012
  • It has been studied to support data having multiple properties, called Skyline Query. The skyline query is not exploring data having all properties but only meaningful data, when we retrieve informations in large data base. The skyline query can be used to provide some information about various environments and situations in sensor network. However, the legacy skyline query has a problem that increases the number of comparisons as the number of sensors are increasing in multi-dimensional data. Also important values are often omitted. Therefore, we propose a new method to reduce the complexity of comparison where the large number of sensors are placed. To reduce the complexity, we transfer a CMF(Category Based Member Function) which can identify preference of specific data when interest query from sync-node is transferred to sub-node. To show the validity of our method, we analyzed the performance by simulations. As a result, it showed that the time complexity was reduced when we retrieved information in multiple sensing data and omitted values are detected by great dominance Skyline.

A Large Scale Distributed Presence Service System by SIP Message Control Session (SIP 메시지 제어 세션에 의한 대용량 분산 프레즌스 서비스 시스템)

  • Jang, Choonseo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.5
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    • pp.514-520
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    • 2018
  • Presence service provides various information about users such as locations, status of on/offline and network access methods, and number of presence resources required by each users increases largely in mobile environment. Therefore an effective method which can reduce load of presence servers is needed. In this paper, a large scale distributed presence service system which can distribute effectively total presence system load of presence servers using message control session has been presented. This large scale distributed presence service system provides various presence information for massive volumes of users. In this study, a new message control session architecture which can dynamically distribute loads of the presence servers to multiple servers has been presented, and a new presence information data architecture for controlling load of the presence servers has been designed. In this architecture, each presence server can exchange current load level in real time to get variance of the total system load change according to user numbers, and can distribute system load to maintain load level of each server evenly. The performance of the proposed large scale distributed presence service system has been analysed by experiments. The results has been showed that average presence resource subscription processing time reduced from 42.6% to 73.6%, and average presence notification processing time reduced from 37.6% to 64.8%.

A Study on 3[kW] PMA-RSG Optimal Design for Mobile Power Supply (이동형 전원장치용 3[kW] PMA-RSG의 최적 설계에 대한 연구)

  • Baik, Jei-Hoon;Toliyat, Hamid A.;Kim, Nam-Hun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.6
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    • pp.109-117
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    • 2009
  • In this paper, an analytical model using equivalent magnetic circuits for the PMA-SynRG is presented. The lumped parameter model (LPM) is developed from machine geometry, stator winding and machine operating specifications. By the LPM, magnetic saturation of rotor bridges is incorporated into model and it provides effective means of predicting machine performance for a given machine geometry. The LPM is not as accurate as finite element analysis but the equivalent magnetic circuits provide fast means of analyzing electromagnetic characteristics of PMa-SynRG. It is the main advantage to find the initial design and optimum design. The initial design of PMa_RSG is performed by LPM model and FEM analysis, and the final PMA-RSG design is optimized and identified by FEM analysis considering actual machine design. The linear LPM and the nonlinear LPM are programmed using MATLAB and all of machine parameters are calculated very quickly. To verify justification of the proposed design of PMa-RSM, back-EMF is measured.

The Mechanism of Proxy Mobile IPv4 to Minimize the Latency of Handover Using MIH Services (MIH 서비스를 활용한 Proxy Mobile IPv4의 핸드오버 지연 최소화 방안)

  • Kim, Sung-Jin;You, Heung-Ryeol;Rhee, Seuck-Ho
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.211-217
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    • 2008
  • Recently, there are many efforts to support seamless mobility in 802.11 WLANs using IP Layer mobility protocols. The IP layer mobility protocols are the most efficient mechanism to guarantee the service session continuity when IP subnet is changed during handover. Even if the IP layer mobility protocols are quite efficient, the feature of the protocols that had been designed to consider only L3 layer makes it difficult to improve the performance of hand over more and more. Nowadays, to overcome this limitation of IP mobility protocols, many researchers have worked on the mobility protocols integration of different layers (e.g., L2 layer). In this paper, we propose the enhanced Proxy MIPv4 to minimize the latency of handover using MIH protocol in 802.11 WLANs. The proposed mechanism minimizes the latency of authentication by exchanging security keys between Access Routers during handover. Moreover, it also minimizes packet losses by Inter-AP Tunneling and data forwarding.

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Speed Control of Marine Gas Turbine Engine using Nonlinear PID Controller (비선형 PID 제어기를 이용한 선박용 가스터빈 엔진의 속도 제어)

  • Lee, Yun-Hyung;So, Myung-Ok
    • Journal of Navigation and Port Research
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    • v.39 no.6
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    • pp.457-463
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    • 2015
  • A gas turbine engine plays an important role as a prime mover that is used in the marine transportation field as well as the space/aviation and power plant fields. However, it has a complicated structure and there is a time delay element in the combustion process. Therefore, an elaborate mathematical model needs to be developed to control a gas turbine engine. In this study, a modeling technique for a gas generator, a PLA actuator, and a metering valve, which are major components of a gas turbine engine, is explained. In addition, sub-models are obtained at several operating points in a steady state based on the trial running data of a gas turbine engine, and a method for controlling the engine speed is proposed by designing an NPID controller for each sub-model. The proposed NPID controller uses three kinds of gains that are implemented with a nonlinear function. The parameters of the NPID controller are tuned using real-coded genetic algorithms in terms of minimizing the objective function. The validity of the proposed method is examined by applying to a gas turbine engine and by conducting a simulation.

The study of improving the performance of lower direction finding ability due to the interfered phase difference of circular array Antennas (원형배열안테나의 위상간섭에 의한 방향탐지 성능저하 개선연구)

  • Chung, Jae-Woo;Kim, Young-Kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.535-539
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    • 2010
  • This paper include to study DoA(Direction of Arrival) for radio collection and monitoring system. The direction finding calculated by applying the CVDF (Correlation Vector Direction Finding) algorithm for the five circular dipole antenna over V / UHF band. To improve the accuracy of direction finding by applying CVDF algorithm needs to obtain ideal phase difference each antennas. However, a circular array antenna phase difference pattern may be distorted on a specific frequency band or to particular direction. The effect of installing each array antennas circularly and the effect of the interference of center pole (located in the center of a circular array antenna mount) may make the distortion of phase pattern. If you use an active antenna instead of passive antenna to obtain good sensitivity, you would measure the more distortion. This paper propose how to change combination of antennas to measure the phase in real-time and how to use antenna beam patterns for minimizing the degradation phenomena at applying simple CVDF algorithm and increasing the direction finding capability.

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Cause Investigation for the Flooding and Sinking Accident of the Ro-Ro Ferry Ship (로로 여객선의 침수 및 침몰사고 원인규명)

  • Chung, Young-Gu;Lee, Jae-Seok;Ha, Jung-Hoon;Lee, Sang-Gab
    • Journal of Navigation and Port Research
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    • v.44 no.3
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    • pp.264-274
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    • 2020
  • The Ro-Ro ferry ship capsized and sank to the bottom of the sea because of the rapid turning for several reasons, such as lack of stability due to the center of gravity rise from the extension and rebuilding of the stern cabin, excessive cargo loading, and shortage ballast, poor lashing, etc. The purpose of this study was to investigate and analyze the cause of the ship's rapid flooding, capsizing, and sinking accident according to rapid turning scientifically and accurately using the Fluid-Structure Interaction( FSI) analysis technique. Several tests were conducted for this cause investigation of the flooding and sinking accident correctly and objectively, such as the realization of the accurate ship posture tracks according to the accident time using several accident movies and photos, the validation of cargo moving track, and sea water inflow amount through the exterior openings and interior paths compared with the ship's posture according to the accident time using the floating simulation and hydrostatic characteristics program calculation, and the performance of a full-scale ship flooding·sinking simulation.