• Title/Summary/Keyword: Facility maintenance

Search Result 872, Processing Time 0.027 seconds

Evaluating Level of Information Provided According to User Satisfaction of VMS on the Continuous Traffic Flow (연속류 도로 VMS의 이용자를 고려한 정보제공수준 평가)

  • Sin, So-Yeong;Lee, Su-Beom;Im, Jun-Beom;Hong, Ji-Yeon
    • Journal of Korean Society of Transportation
    • /
    • v.29 no.3
    • /
    • pp.49-58
    • /
    • 2011
  • As a part of the ITS, the traffic information system is more widely adopted to deliver traffic information to vehicle drivers via various types of media. As the ITS system establishment has been recognized as somewhat accomplished, the focus has shifted to the efficient operation and maintenance of the system. In this paper, we propose a method for evaluating a VMS traffic information service system from a user's perspective. In particular, relational expressions for the level of information provided and the level of user satisfaction are generated for the evaluation to take place from the user psychological satisfaction aspect of all other beneficial features of the system. As continuous flow facility is the one that has limited entry and exit, the traffic information of VMS plays a significant role for vehicle drivers to make their decisions. A method suggested in this paper could be used for evaluating an existing system as well as setting up the target service level of the system of a new system. If individual system properties are considered along with various VMS functions being as supplement of this research, more systematic evaluation method could be arranged.

Prevention of Insulation Damage Layer and Shell Corrosion in Thermal Storage Tanks for District Heating (지역난방용 축열조의 단열재 손상과 외각부식 개선방안)

  • Bang, Yong-Eoon;Yoo, Ho-seon
    • Plant Journal
    • /
    • v.10 no.4
    • /
    • pp.35-41
    • /
    • 2014
  • The height and capacity of the thermal storage tank can be decided by the altitude and heat load of the heat supply area. Evaporation in heat pipe can be prevented by pressurizing it with the hydraulic head of the thermal storage tank. In addition, it absorbs the expanded volume from the temperature changes and supplies water to the pipelines in case of the shortage of water. One of the most important roles of the thermal storage tank is a stable heat supply facility. It can control the heat demand by accumulating the surplus heat and supplying in changing heat demand time. The purpose of this thesis is to be helpful for the operation and maintenance of the thermal storage tanks. The study has been carried out for 18 thermal storage tanks, which have been used polyurethane foam as insulation, among 27 tanks in district heating plants. The characteristics of the insulation materials, the reasons for the damages of the insulation and how impact the insulation damages to the corrosion of the thermal storage tank have been studied.

  • PDF

Establishment of Efficient Organization for Coordination Center on Clinical Research in Traditional Korean Medicine (한의학임상협연연구의 필요성과 효율적인 조직체계의 구축)

  • Ko Seong-Gyu;Jun Chan-Yong;Park Jong-Hyeong;Han Chang-Ho;Jung Woo-Sang;Moon Sang-Kwan;Cho Ki-Ho;Kim Young-Suk;Bae Hyung-Sup
    • The Journal of Korean Medicine
    • /
    • v.27 no.1 s.65
    • /
    • pp.196-203
    • /
    • 2006
  • Objectives : The aim of this study is to investigate how does the methods of treatment and diagnosis of Traditional Korean Medicine(TKM) get the evidence of efficacy and safety and what type of efficient body and appropriate facility of the coordination center for clinical trial in TKM. Methods : We have got the information of clinical trial center or clinical collaboration center by site invitation, search of paper and reports and internet exploration for the domestic or foreign site. Results : Coordination center for clinical trial usually involves every steps of clinical trials, such as development of Case Report From (CRF), design of study, calculation of sample size, randomization, maintenance of blinding, monitoring and audit of the resource document, data and CRF, data entry, quality control of data, analysis and report. Conclusions : The body needs several aresa of experts, which are epidemiologists, biostatisticians, research nurses for coordination, data manager and programmer, and administrator. This body would be enhance and help he clinical researches including clinical trials in TKM.

  • PDF

Numerical Study on a Hydrogen Recirculation Ejector for Fuel Cell Vehicle (연료전지 수소재순환 이젝터 시스템에 관한 수치해석적 연구)

  • NamKoung, Hyuck-Joon;Moon, Jong-Hoon;Jang, Seock-Young;Hong, Chang-Oug;Lee, Kyoung-Hoon
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2007.11a
    • /
    • pp.156-160
    • /
    • 2007
  • Ejector system is a device to transport a low-pressure secondary flow by using a high-pressure primary flow. Ejector system is, in general, composed of a primary nozzle, a mixing section, a casing part for suction of secondary flow and a diffuser. It can induce the secondary flow or affect the secondary chamber pressure by both shear stress and pressure drop which are generated in the primary jet boundary. Ejector system is simple in construction and has no moving parts, so it can not only compress and transport a massive capacity of fluid without trouble, but also has little need for maintenance. Ejectors are widely used in a range of applications such as a turbine-based combined-cycle propulsion system and a high altitude test facility for rocket engine, pressure recovery system, desalination plant and ejector ramjet etc. The primary interest of this study is to set up an applicable model and operating conditions for an ejector in the condition of sonic and subsonic, which can be extended to the hydrogen fuel cell vehicle. Experimental and theoretical investigation on the sonic and subsonic ejectors with a converging-diverging diffuser was carried out. Optimization technique and numerical simulation was adopted for an optimal geometry design and satisfying the required performance at design point of ejector for hydrogen recirculation. Also, some sonic and subsonic ejectors with the function of changing nozzle position were manufactured precisely and tested for the comparison with the calculation results.

  • PDF

A Study on the Analysis of Human-errors in Major Chemical Accidents in Korea (국내 화학사고의 휴먼에러 기반 분석에 관한 연구)

  • Park, Jungchul;Baek, Jong-Bae;Lee, Jun-won;Lee, Jin-woo;Yang, Seung-hyuk
    • Journal of the Korean Society of Safety
    • /
    • v.33 no.1
    • /
    • pp.66-72
    • /
    • 2018
  • This study analyses the types, related operations, facilities, and causes of chemical accidents in Korea based on the RISCAD classification taxonomy. In addition, human error analysis was carried out employing different human error classification criteria. Explosion and fire were major accident types, and nearly half of the accidents occurred during maintenance operation. In terms of related facility, storage devices and separators were the two most frequently involved ones. Results of the human error-based analysis showed that latent human errors in management level are involved in many accidents as well as active errors in the field level. Action errors related to unsafe behavior leads to accidents more often compared with the checking behavior. In particular, actions missed and inappropriate actions were major problems among the unsafe behaviors, which implicates that the compliance with the work procedure should be emphasized through education/training for the workers and the establishment of safety culture. According to the analysis of the causes of the human error, the frequency of skill-based mistakes leading to accidents were significantly lower than that of rule-based and knowledge based mistakes. However, there was limitation in the analysis of the root causes due to limited information in the accident investigation report. To solve this, it is suggested to adopt advanced accident investigation system including the establishment of independent organization and improvement in regulation.

Performance Analysis on a Hydrogen Recirculation Ejector for Fuel Cell Vehicle (연료전지 수소재순환 이젝터 성능 해석)

  • NamKoung, Hyuck-Joon;Moon, Jong-Hoon;Jang, Seock-Young;Hong, Chang-Oug;Lee, Kyoung-Hoon
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.256-259
    • /
    • 2008
  • Ejector system is a device to transport a low-pressure secondary flow by using a high-pressure primary flow. Ejector system is, in general, composed of a primary nozzle, a mixing section, a casing part for suction of secondary flow and a diffuser. It can induce the secondary flow or affect the secondary chamber pressure by both shear stress and pressure drop which are generated in the primary jet boundary. Ejector system is simple in construction and has no moving parts, so it can not only compress and transport a massive capacity of fluid without trouble, but also has little need for maintenance. Ejectors are widely used in a range of applications such as a turbine-based combined-cycle propulsion system and a high altitude test facility for rocket engine, pressure recovery system, desalination plant and ejector ramjet etc. The primary interest of this study is to set up an applicable model and operating conditions for an ejector in the condition of sonic and subsonic, which can be extended to the hydrogen fuel cell vehicle. Experimental and theoretical investigation on the sonic and subsonic ejectors with a converging-diverging diffuser was carried out. Optimization technique and numerical simulation was adopted for an optimal geometry design and satisfying the required performance at design point of ejector for hydrogen recirculation. Also, some ejectors with a various of nozzle throat and mixing chamber diameter were manufactured precisely and tested for the comparison with the calculation results.

  • PDF

Design consideration and explosion safety of underground ammunition storage facilities (지하탄약고의 설계요소 및 폭발안전 연구)

  • Kim, Oon-Young;Lee, Myung-Jae;Kim, Min-Seok;Kim, Joon-Youp;Joo, Hyo-Joon
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.5 no.1
    • /
    • pp.55-70
    • /
    • 2003
  • Ammunition magazine, which is installed on the ground, has difficulty in protecting from the external attack, and accidental explosion should cause great damage to the life and property. For these reasons, it is needed to develop underground magazine that it has the advantages of safety, security and maintenance. This paper introduce the design case for blasting facilities, which should resist blasting pressure, as well as layout of underground magazine, which takes a safety for explosion and a working space of loading/unloading machine into consideration. On the layout, in case of ${\bigcirc}{\bigcirc}$ underground magazine, put three storage chambers in position almost parallel with principle stress direction, where less effected on discontinuity and hard rock area. Also, secured safe distance according to safety criteria of the Defense Ministry, and verified suitable layout by trace simulation for loading/unloading machine on working stage. Blasting design was performed on evaluation of maximum blast pressure between donar and acceptor chambers, and design condition for blast door, valve, etc. Diminution facilities against explosion, such as thrust block or debris trap, determined its size after plan in accordance with blasting criteria and calculation by structural analysis.

  • PDF

Medical Equipment Support System for Official Development Assistance : Case of Kitengela Health Center in Kenya (공적개발원조 의료기기 지원 체계 연구 : 케냐 키텐젤라 보건소 사례)

  • Choi, Tae-Seon
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.3
    • /
    • pp.257-268
    • /
    • 2016
  • The purpose of this research is to find the cause of low degree of utilization of medical equipment that are provided as Official Development Assistance(ODA) and to suggest an effective medical equipment support system for ODA. This research analyzes the supporting process of the medical equipment as ODA in Kitengela Health Center in Kenya. As the result of analysis, it has been found that the following problems. 1) It was found that users was attended insufficient to demand medical equipment. 2) The determination of medical equipment request was inadequate. 3) It was appeared to be organized the compilation of the budget for purchases and operation of medical equipment 4) The improvement of procurement system of medical equipment was appeared to need. 5) It was appeared to need to build conditions for installation of medical equipment. 6) It was necessary to secure finance, to conduct periodic management training, and to ensure available human resources in management and maintenance in order to sustain the medical equipment management ability and it is encouraged to promote leadership in healthcare facility management. Finally, the theoretical and practical implications of this research are discussed.

Preliminary Investigation for Apply of e-Government Framework at the Construction CALS System (건설CALS시스템에 전자정부 표준프레임워크 적용을 위한 사전 고찰)

  • Yang, Sung-Hoon;Kim, Nam-Gon
    • The Journal of the Korea Contents Association
    • /
    • v.13 no.11
    • /
    • pp.433-440
    • /
    • 2013
  • The Ministry of Land, Infrastructure and Transport was developed the Construction CALS system for improvement of the construction economy. Construction CALS system is consist by Construction Portal System, Construction Management System, Construction Authorization and Permission System, Compensation Management System, Facility Maintenance Management System and has utilized at construction site of more than 900. Ministry of Land, Infrastructure and Transport and related researcher was proposed method of various function improvements for usability of the system. However, the proposed method was expanded the problems like increase of system management cost and development cost with decrease of data process rate. The problem was increases because has added of only service function without modify of software structure to the system on each different platform base. One of the methods for solving problems is to apply the e-Government framework and then integrated the different platform. The purpose of this paper is analyse of the applicability and efficiency of e-Government framework to the construction CALS system. For that was analyzed the e-Government standard framework and the developments case. And then was verified about the adaption possibility and efficiency by use the Function Point tool.

A Design and Implementation of Web-based System for Real-Time Infographics of Airport Refueling Facilities (공항 급유 설비의 실시간 인포그래픽을 위한 웹 기반 시스템 설계 및 구현)

  • Shin, Seung-Hyeok
    • Journal of Advanced Navigation Technology
    • /
    • v.19 no.4
    • /
    • pp.305-310
    • /
    • 2015
  • A controlling system for airport refueling facilities is connected to sensors which collect various informations. Informations which are transmitted at a high speed in various sensors are processed by a dedicated software in the controlling system. The problems of system maintenance and network traffic caused by the use of dedicated software reduce the efficiency of the system operation. Therefore, a web-based system that can be accessed using the Internet environment is required. In this paper, we propose a system showing web-based real-time informations. To do this, we change the function of the communication by each sensor to a facade structure, and design a system for transferring web-based real-time informations. Also we propose data-driven infographics for displaying the real-time big data information at a high speed on the web. Finally, we compare and analyse the proposed system between the existing system and show that our system can effectively display the real-time information on the web.