• Title/Summary/Keyword: space utilization

Search Result 1,059, Processing Time 0.032 seconds

Application of Instantaneous sinusoidal current tracking control inverter for photovoltaic system (순시직전류(瞬時直電流) 추종제어형(追從制御形) Inverter의 태양광발전(太陽光發電) 시스템에의 응용(應用))

  • Yu, Kwon-Jong;Jung, Myung-Woong;Song, Jin-Soo
    • Proceedings of the KIEE Conference
    • /
    • 1990.07a
    • /
    • pp.372-375
    • /
    • 1990
  • A sinusoidal PWM type inverter using 1GBT and a new instantaneous current tracking control stategy is described. Its utilization as an interface for a grid-connected photovoltaic system with maxmum power tracking capability is explaned, and competer simulation along with waveforms are discussed. Finally, experimental results are analysed by state space avarge method to actual grid-connected systems.

  • PDF

A New Estimation Method of Video Traffic Specification in QoS-guaranteed Networks

  • Thang, Truong Cong;Ro, Yong Man
    • Journal of Broadcast Engineering
    • /
    • v.8 no.1
    • /
    • pp.45-53
    • /
    • 2003
  • Traffic specification plays a crucial role in the resource reservation for video services over the packet-switching networks. The current development of QoS-guaranteed service still leaves a wide space for the selection of traffic specification. We propose a new method to estimate the traffic specification of variable-bit-rate (VBR) video for deterministic service. The method is based on the concept of empirical envelope and the delay bound. The solution shows to be simple yet it provides excellent network utilization.

Travel-Time Analysis for an Automated Mobile Racking System (이동랙(移動 rack) 자동창고의 주행(走行)시간 분석)

  • Lee, Moon-Kyu
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.21 no.2
    • /
    • pp.195-206
    • /
    • 1995
  • Higher utilization of warehouse space can be achieved by using automated mobile racking systems. Therefore, those systems may be employed for factories or distribution centers as a good option of increasing the storage capacity. In this paper, travel-time models are developed to estimate the average performance of the system assuming randomized storage. Expected travel times are determined for both single- and dual-command cycles. Two extreme input/output-point locations are considered. Some numerical results obtained from the models are given.

  • PDF

Analysist of Instantaneous Current Tracking Control Inverter Characteristics for Photovoltaic System (태양광 발전용 순시치 전류제어형 인버터의 특성 해석)

  • 조금배;김한성
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.43 no.5
    • /
    • pp.770-778
    • /
    • 1994
  • In this paper, the photovoltaic inverter system with instantaneous sinusoidal current tracking control is proposed to improve the utilization factor of photovoltaic power system which would be connected utility interactive system. The proposed inverter is designed to track maximum power point by two-state value control method and utility interactive operation, and to decrease output harmonics component. Optimal operating region is described by state space averaging method, and present tracking condition of standard guide line. The experimental result shows the effectiveness of inverter system using the instantaneous control method.

A new estimation method of video traffic specification in QoS-guaranteed networks

  • Thang, T.C.;Ro, Y.M.
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2002.11a
    • /
    • pp.85-90
    • /
    • 2002
  • Traffic specification plays a crucial role in the resource reservation for video services over the packet-switching networks. The current development of QoS-guaranteed service still leaves a wide space for the selection of traffic specification. We propose a new method to estimate the traffic specification of variable-bit-rate (VBR) video for deterministic service. The method is based on the concept of empirical envelope and the delay bound. The solution shows to be simple yet it provides excellent network utilization.

  • PDF

A Study on the Establishment of Preservation Area for the Preservation of Historical and Cultural Space in the Ancient Village - Focused on the Hongcun, China - (고촌락 역사문화공간 보존을 위한 보호구역 설정 방안 연구 - 중국 굉촌을 중심으로 -)

  • Shin, Hyun-Sil;Dai, Gai-Rong
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.40 no.1
    • /
    • pp.65-73
    • /
    • 2022
  • This paper analyzed the characteristics of ancient villages in Hongcun and the method of resetting the preservation area for the preservation of the changed historical and cultural space in Hongcun through the process of change. To this end, the current status of preservation areas and utilization areas in the village was identified through ancient documents, old paintings, policy materials, and interviews related to the village, and through this, the problem of resetting the preservation area was examined. As a result, the following conclusions were drawn. First, Hongcun is a village built under the influence of Confucianism, Buddhism, and Taoism, and the spatial organization was created according to the hierarchy of Confucianism. As a result, it was possible to inherit and preserve the heritage of ancestors even though the central government did not preserve it. Second, the concept of preservation in a limited sense has been applied as Hongcun has been recognized as a cultural heritage that has been passed down since ancient times, but the Great Leap Forward and the Cultural Revolution brought about changes in the village space. Since then, ancient buildings, water systems, and forests have been preserved through regulations on new construction and expansion of a building with the Hongchon preservation plan, but the development within the preservation area is underway due to changes in the lives of original inhabitants, which were followed by continued development pressure and reform and opening. Third, the original inhabitant of ancient villages had a high perception of the value of the heritage, but they demanded the preparation of measures to improve living conditions and create profits, and the active use of villages for this. Fourth, the forest consisting of old trees is being restored, but the gardens in the old house are showing a phenomenon that the garden space is reduced or transformed for use. The bridges and parking lots were newly built in the southern area, which was extended from the western area, the original entrance to the ancient village, resulting in changes in the existing entrance. This was found to be the primary cause of the spatial change of the ancient village, as the road system was modified to make it convenient for tourists to enter and exit. Fifth, the existing preservation area should be reset and preserved by resetting the preservation route centered on Wolso(half Moon Pool), while the surrounding area should be set as a direct and indirect experience space, and according to the hierarchy of each space, the utilization should proceed while the preservation is carried out by crossing the preservation and the utilization.

Analysis of Hydroelastic Response of a Pontoon-type Structure Considering Effect of Wave Breaker with Underwater Opening (해수순환 방파제를 고려한 폰툰형 구조물의 유탄성응답 해석)

  • 홍사영;최윤락;홍석원
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.40 no.5
    • /
    • pp.53-59
    • /
    • 2003
  • Ocean space utilization using VLFS(Very Large Floating Structures) can provide environmental impact free space by allowing sea water flow freely through the floating structure. Use of Pontoon type VLFS for that purpose needs employment of breakwaters for reduction of wave effects. Therefore, in order to maximize advantage of environmental impact free structure, the breakwater should be the one that can allow water flow freely through it, too. In this paper hydroelastic response of a pontoon type structure is analyzed considering breakwaters which allow water flow through its opening at bottom of the breakwaters. Mode superposition technique is used for solving equation of flexible body while interactions between the pontoon and breakwaters is considered based on generalized mode concept. Bi-quadratic nine node higher-order boundary element method is adopted for more accurate numerical treatment near sharp edged body shape. Performance of various combinations of breakwaters is investigated.

Optimization of LU-SGS Code for the Acceleration on the Modern Microprocessors

  • Jang, Keun-Jin;Kim, Jong-Kwan;Cho, Deok-Rae;Choi, Jeong-Yeol
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.14 no.2
    • /
    • pp.112-121
    • /
    • 2013
  • An approach for composing a performance optimized computational code is suggested for the latest microprocessors. The concept of the code optimization, termed localization, is maximizing the utilization of the second level cache that is common to all the latest computer systems, and minimizing the access to system main memory. In this study, the localized optimization of the LU-SGS (Lower-Upper Symmetric Gauss-Seidel) code for the solution of fluid dynamic equations was carried out in three different levels and tested for several different microprocessor architectures widely used these days. The test results of localized optimization showed a remarkable performance gain of more than two times faster solution than the baseline algorithm for producing exactly the same solution on the same computer system.

Calibration of Inertial Measurement Units Using Pendulum Motion

  • Choi, Kee-Young;Jang, Se-Ah;Kim, Yong-Ho
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.11 no.3
    • /
    • pp.234-239
    • /
    • 2010
  • The utilization of micro-electro-mechanical system (MEMS) gyros and accelerometers in low-level inertial measurement unit (IMU) influences cost effectiveness in a positive way under the condition that device error characteristics are fully calibrated. The conventional calibration process utilizes a rate table; however, this paper proposes a new method for achieving reference calibration data from the natural motion of pendulum to which the IMU undergoing calibration is attached. This concept was validated with experimental data. The pendulum angle measurements correlate extremely well with the solutions acquired from the pendulum equation of motion. The calibration data were computed using the regression method. The whole process was validated by comparing the measurement from the 6 sensor components with the measurements reconstructed using the identified calibration data.

FMS에서의 Deadlock 탐지와 방지에 관한 연구

  • Lim, Dong-Sun
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.20 no.1
    • /
    • pp.53-69
    • /
    • 1994
  • Deadlock in flexible manufacturing systems (FMS) which refers to the stop state of job flow in the system can be commonly occurred in operating FMS. This state mainly due to bad movements of jobs and commonly job routings should be avoided to maximize the utilization of high-capital resources in this study, the deadlock generated from the conflict between flow objects competing to occupy space resources in FMS is investigated. Capacity Designated Directed Graph (CDG) is constructed to represent the space resources and flow object routings. From the characteristics of CDG, an algorithm for the detection of the deadlock possibility is proposed. Finally two deadlock avoidance rule are proposed and implemented in the control on Automated Guided Vehicle system in an FMS.

  • PDF