• Title/Summary/Keyword: operation research

Search Result 12,940, Processing Time 0.047 seconds

A Study on the Satellite Launch Vehicle Separation Detection Interface to Improve the Reliability of the Launch and Early Operation Phase

  • Lee, Nayoung;Kwon, Dong-young;Jeon, Hyeon-Jin;Jeon, Moon-Jin;Cheon, Yee-Jin
    • Journal of Aerospace System Engineering
    • /
    • v.15 no.4
    • /
    • pp.57-63
    • /
    • 2021
  • The launch vehicle (LV) separation detection interface of the satellite, which is designed to initiate the launch and early operation phase (LEOP) for S-band data transmission and the solar array deployment after the LV separation, is one of the hazard items at the launch site. Therefore, this interface should satisfy the single-fault tolerance requirement for the range safety. In this paper, we discuss the LV separation detection interfaces for two different satellite launch configurations and propose a method to guarantee for the satellite to start the LEOP even under the emergency case such as a partial separation from the LV. Furthermore, the proposed method meets the range safety requirement of the launch site. As this method only changes the external harness configuration of the satellite, it increases the reliability of the satellite early operation without any modification of the existing internal logics to detect the separation event.

A study on dynamic simulation for estimation of leakage current (누설전류 예측을 위한 동적 시뮬레이션에 관한 연구)

  • Jung, Ho-Sung;Han, Moon-Seob;Park, Young;Chung, Sang-Gi;Kwon, Sam-Young;Lee, Jea-Bong
    • Proceedings of the KIEE Conference
    • /
    • 2008.11a
    • /
    • pp.250-252
    • /
    • 2008
  • DC traction system generates leakage current because running rails are used in return circuit. And it is very important to estimate the leakage current to the train operation situation. Therefore this paper presents dynamic simulation technique that is very similar to the real operation situation using TPS and PSCAD/EMTDC. For this we model DC traction system included in DC substation, variable feeding circuit model and variable train model. And we extract train location and power using TPS program and use these data for dynamic simulation. Finally we can estimate leakage current to the various operation condition using dynamic simulation.

  • PDF

Quick Evaluation of Spacecraft Orbit Maneuver Using Small Sets of Real-time GPS Navigation Solutions

  • Lee, Byoung-Sun;Lee, Ho-Jin;Lee, Seong-Pal;Kim, Jong-Ah;Park, Hae-Jin
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.458-458
    • /
    • 2000
  • Quick evaluations of two in-plane orbit maneuvers using small see of real-time CPS navigation solutions were peformed lot the KOMPSAT-1 spacecraft operation. Real-time GPS navigation solutions of the KOMPSAT-1 were collected during the Korean Ground Station(KGS) pass. Only a few sets of position and velocity data after completion of the thruster firing were used for the quick maneuver evaluations. The results were used for antenna pointing data predictions for the next station contact. Normal orbit maneuver evaluations using large see of playback GPS navigation solutions were also performed and the result were compared with the quick evaluation results.

  • PDF

Study on anode in SOFC (SOFC 연료극의 전극특성)

  • Eom, S.W.;Kim, G.Y.;Moon, S.I.;Lim, H.C.;Lee, C.W.
    • Proceedings of the KIEE Conference
    • /
    • 1995.11a
    • /
    • pp.404-405
    • /
    • 1995
  • Solid Oxide Fuel Cell has advantage of high utility because of having high operation temperature. In case of anode, Ni and YSZ being widly used as anode start materials. But Ni can be sintered during operation because that its operation temperature is very high, so it cause to lower the cell performance. It is very important to control the ratio of Ni to YSZ. In this paper, we studed on characterization of anode by controlling the Ni-YSZ contents.

  • PDF

Life Comparision of 2$\frac{1}{2}$ Ton Truck Considering The Operation Terrains (운행지형형태에 따른 2$\frac{1}{2}$톤 트럭의 수명비교)

  • Kim Jang-Hyeon;Ha Seok-Tae
    • Journal of the military operations research society of Korea
    • /
    • v.16 no.2
    • /
    • pp.1-13
    • /
    • 1990
  • The life of an equipment depends upon its operating characteristics and physical environment factors. This paper presents the economic life length of 2 1/2 ton truck considering the operation terrains. For this specific research, the operation terrains are categorized into seacoast area, mountain area and plain area. To compute the life length, the method of equivalent annual cost is employed. The sample vehicles from each corresponding area are randomly selected from those vehicles whose ages exceed 9 years. This research finds the following results : (1) The life length operated at seacoast area is 9.75 years, (2) The life length operated at mountain area is 11.25 years, (3) The life length operated at plain area is 14 years. This research argues that the key factor such as characteristics of operating enviroment for allocation of operating and maintaining cost should be considered.

  • PDF

Study on DAS-Based Time Synchronization for Improving Reliability of Section Load Estimation

  • Lee, In-tae;Lee, Ji-Hoon;Jung, Nam-Joon;Jung, Young-Beom;Lee, Byung-sung
    • KEPCO Journal on Electric Power and Energy
    • /
    • v.1 no.1
    • /
    • pp.61-65
    • /
    • 2015
  • For effective distribution planning and operation, we need a reliable estimation of operation capacity. But it is difficult to ensure reliability due to the low accuracy of section load data, which is used as a basis in estimating the operation capacity. This paper discusses how to improve the accuracy of section load data by analyzing the existing method of estimating the section load, using statistical techniques to adjust the acquired data, and using the section load estimation algorithm to estimate the section load based on the adjusted data.

DISTRIBUTED CONTROL SYSTEM FOR KSTAR ICRF HEATING

  • Wang, Son-Jong;Kwak, Jong-Gu;Bae, Young-Dug;Kim, Sung-Kyu;Hwang, Churl-Kew
    • Nuclear Engineering and Technology
    • /
    • v.41 no.6
    • /
    • pp.807-812
    • /
    • 2009
  • An ICRF discharge cleaning and a fast wave electron heating experiment were performed. For automated operation and providing the diagnostics of the ICRF system, the ICRF local network was designed and implemented. This internal network provides monitoring, RF protection, remote control, and RF diagnostics. All the functions of the control system were realized by customized DSP units. The DSP units were tied by a local network in parallel. Owing to the distributed feature of the control system, the ICRF local control system is quite flexible to maintain. Developing the subsystem is a more effective approach compared to developing a large controller that governs the entire system. During the first experimental campaign of the KSTAR tokamak, the control system operated as expected without any major problems that would affect the tokamak operation. The transmitter was protected from harmful over-voltage events through reliable operation of the system.

Analysis of Remote Operation involved in Spent Nuclear Fuel Conditioning Process using its Virtual Mockup

  • Yoon, Ji-Sup;Kim, Sung-Hyun;Song, Tai-Gil
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.840-845
    • /
    • 2004
  • The remote operation of the Advanced Spent Fuel Conditioning Process (ACP) is analyzed by using the 3D graphic simulation tools. Since the spent nuclear fuel, which is a high radioactive material, is processed in the ACP, the ACP equipment is operated in intense radiation fields as well as in a high temperature. Thus, the equipment is operated in a remote manner and should be designed with consideration for the remote handling and maintenance. Also suitable remote handling technology needs to be developed along with the design of the process concepts. For this we developed a graphic simulator, which provides the capability of verifying the remote operability of the ACP without the fabrication of the process equipment. In other words, by applying virtual reality to the remote maintenance operation, a remote operation task can be simulated in the graphic simulator, not in the real environment. The graphic simulator will substantially reduce the cost of the development of the remote handling and maintenance procedure as well as the process equipment, while at the same time developing a remote maintenance concept that is more reliable, easier to implement, and easier to understand.

  • PDF

Development of the Regulatory Guidelines for Continued Operation of CANDU Reactor in Korea (CANDU형 원전 계속운전 평가지침서 개발)

  • Choi, Young-Hwan;Kim, Hong-Key
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.34 no.4
    • /
    • pp.495-499
    • /
    • 2010
  • In this paper, the regulatory guidelines for the continued operation of the CANDU reactor in Korea were introduced. Wolsong Unit 1, which is a CANDU 600 reactor in Korea, will reach its design life of 30 years in 2012. A licensee who wants to operate a nuclear power plant beyond its design life should submit reports of periodic safety reviews (PSRs) conducted on the basis of 11 safety factors. In addition, the licensee should provide the following: (1) scoping and screening results for aging management, (2) aging management program, (3) TLAA, including the continued operation term, (4) operation-experience feedback, and (5) important safety-research results. In this study, 54 regulatory guidelines for the five above-mentioned items for the CANDU reactor in Korea were developed.