• Title/Summary/Keyword: breakdown structure

Search Result 685, Processing Time 0.03 seconds

작업분류체계(WBS)를 이용한 안전해체공사 시스템 개발에 관한 연구 (A Study on the Development of Safety Demolition Work System by using Work Breakdown Structure)

  • 김광서;양극영;이용수;윤여완;김천학
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제2권3호
    • /
    • pp.176-187
    • /
    • 1998
  • The Dismantlement and Construction of the buildings have the characteristic of floating change with repetition within a Time Schedule which has fixed resources, that is, Manpower, Materials and Equipments, and involve many disaster factors in performing each processes. But as these factors are variable, a work supervisor should be able to understand data analysed distinctive factors of each activities systematically, organizationally, and scientifically, and diagrammatic information media so that he can control any complex and situation beyond forecast. Thus this study is intended to be a barometer of weighing if the existing process schedule has taken security into consideration by making the characteristics of organization and action of Work package per process in a building field with more factors like these into a network system and is intended to minimize construction disasters by systematizing this into a Transformational Network.

  • PDF

Cost-effective structural health monitoring of FRPC parts for automotive applications

  • Mitschang, P.;Molnar, P.;Ogale, A.;Ishii, M.
    • Advanced Composite Materials
    • /
    • 제16권2호
    • /
    • pp.135-149
    • /
    • 2007
  • In the automobile industry, structural health monitoring of fiber reinforced polymer composite parts is a widespread need for maintenance before breakdown of the functional elements or a complete vehicle. High performance sensors are generally used in many of the structural health monitoring operations. Within this study, a carbon fiber sewing thread has been used as a low cost laminate failure sensing element. The experimentation plan was set up according to the electrical conductance and flexibility of carbon fiber threads, advantages of preforming operations, and sewing mechanisms. The influence of the single thread damages by changing the electrical resistance and monitoring the impact location by using carbon thread sensors has been performed. Innovative utilization of relatively cost-effective carbon threads for monitoring the delamination of metallic inserts from the basic composite laminate structure is a highlighting feature of this study.

컨테이너 터미널 장비의 RAM 향상을 위한 관리 시스템 (Management System for Improving RAM of Equipment in Container Terminals)

  • 윤원영;김귀래;하영주;손범신;김혜정
    • 산업공학
    • /
    • 제19권3호
    • /
    • pp.245-254
    • /
    • 2006
  • Equipments in container terminal have a lot of parts, and an equipment breakdown affects the productivity of terminal. In this paper, we develop a maintenance management system for improving reliability, availability and maintainability of equipments in container terminals. The developed system consists of five modules : equipment structure module, equipment operation management module, maintenance control module, spare part control module and data analysis module. The system supports reliability engineers to manage and improve RAM of equipments in container terminals. For example, FMEA, failure state analysis and life distribution parameters estimation are easily or automatically done by the system. This system also provides optimal preventive maintenance intervals by simulation and optimal yearly PM schedules for equipments in container terminal are recommended.

Structural and Electrical Properties of Bismuth Magnesium Niobate Thin Films deposited at Various Temperatures

  • Park, Jong-Hyun;Yoon, Soon-Gil
    • Transactions on Electrical and Electronic Materials
    • /
    • 제8권4호
    • /
    • pp.153-156
    • /
    • 2007
  • Structural and electrical properties of the fully crystallized-bismuth magnesium niobate ($Bi_2Mg_{2/3}Nb_{4/3}O_7$, BMN) films with 15 mol% excess bismuth deposited on Pt bottom electrode by pulsed laser deposition are characterized for various deposition temperatures. The BMN films were crystallized with a monoclinic structure from $300^{\circ}C$ and the surface roughness slightly decreases with increasing deposition temperature. The capacitance density of the films increases with increasing deposition temperature and especially, films deposited at $400^{\circ}C$ exhibit a capacitance density of approximately $620nF/cm^2$. The crystallized BMN films with approximately 170 nm thickness exhibit breakdown strength above 600 kV/cm (${\leq}10V$) irrespective of deposition temperature and a leakage current density of approximately $2{\times}10^{-8}A/cm^2$ at 590kV/cm (at 10 V).

건설공사에서 주요공종 대안평가를 위한 품질모델 제안 (A Proposal of Quality Model for Alternative Evaluation of Major Construction Projects)

  • 이종민;서보람;손현정;이태신;양진국;이상범
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
    • /
    • pp.43-44
    • /
    • 2019
  • Major construction projects will be directly related to construction costs and disclosure period depending on the selection of the construction method. However, there are some sites that choose without taking into account sufficient conditions. Therefore, the company wants to present a quality model that suits the characteristics of major engineering fields.

  • PDF

성과관리시스템(EVMS) 도입을 위한 원전 건설사업비 관리체계 세분화 방안에 관한 연구 (A Study on the Cost Hierarchical System of Nuclaer Power Plant Construction Project for Introcusting Earned Vaule Management System)

  • 이상현;김우중
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
    • /
    • pp.230-231
    • /
    • 2019
  • The nuclear power plant construction project is large-scale, has various stakeholders and computer system, and is produced and managed a large amount of information. The domestic nuclear power plant construction project has accumulated data based on many years of experience in the system. It has the competitiveness to suggeest alternatives that meet the requirement of the client in the overseas nuclear power plant project. Earned value management, which integrates schedule and cost, is possible to risk management. It was developed the earned value management system considering the the actual data properties and types of the preceding nuclear power plant construction projects. It will be able to increase the nuclaer power plant export competieiveness. Therefore, it was palned to carry out future stuies so that it be able to complement the measure to integrate cost and schedule in consideration of actual data(quantity of activity, etc.).

  • PDF

Burn Damage에 따른 도막의 방청성 평가 (Evaluation of the Corrosion Protection Coating in Accordance with Burn Damage)

  • 서창호;박진환
    • Corrosion Science and Technology
    • /
    • 제15권6호
    • /
    • pp.290-296
    • /
    • 2016
  • This study was conducted in order to examine the effect of burn damage and the resultant anti-corrosion performance. The breakdown and defect of the paint film caused by burn damage are considered to affect not only the macroscopic appearance but also the adhesive force and the anti-corrosion performance of the paint film. The material of the paint film was epoxy paint that is used most widely for heavy-duty coating, and in order to induce burn damage, heat treatment with a torch was applied to the other side of the paint film. Surface and chemical structure changes according to aging were analyzed using FE-SEM and infrared absorption spectroscopy, and variation in the anti-corrosion performance was analyzed through the AC impedance test.

SOI 응용을 위한 반도체-원자 초격자 구조의 특성 (Characteristics of Semiconductor-Atomic Superlattice for SOI Applications)

  • 서용진
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제53권6호
    • /
    • pp.312-315
    • /
    • 2004
  • The monolayer of oxygen atoms sandwiched between the adjacent nanocrystalline silicon layers was formed by ultra high vacuum-chemical vapor deposition (UHV-CVD). This multilayer Si-O structure forms a new type of superlattice, semiconductor-atomic superlattice (SAS). According to the experimental results, high-resolution cross-sectional transmission electron microscopy (HRTEM) shows epitaxial system. Also, the current-voltage (Ⅰ-Ⅴ) measurement results show the stable and good insulating behavior with high breakdown voltage. It is apparent that the system may form an epitaxially grown insulating layer as possible replacement of silicon-on-insulator (SOI), a scheme investigated as future generation of high efficient and high density CMOS on SOI.

MAS (Metal-$Al_2O_3$-Si) 구조에 있어서 전기적 특성에 관한 연구 (A Study for Electrical Characteristics of MAS (Metal-$Al_2O_3$-Si) Structure)

  • 박성희;이동엽;장지근;이영희
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
    • /
    • pp.461-464
    • /
    • 1987
  • With the fabrication of Al-$Al_2O_3$-n(p) type Si devices, the analysis and measurement of various characteristics, this study presented the electric physical property theory for the charge distribution of MAS device $Al_2O_3$ films, and inquired out the devices available. In order to study them, Al-(450A)$Al_2O_3$-n(p) type Si was the main objects in the study. They were examined through carrier injection, C-V curves of devices on time, ${\Delta}V_{FB}$-t curves, I-V curves and $Al_2O_3$ film's breakdown characteristics.

  • PDF

Twin-well 구조로 제작된 N채널 및 P채널 FET의 특성 (Characteristics of N-and P-Channel FETs Fabricated with Twin-Well Structure)

  • 김동석;이철인;서용진;김태형;김창일;장의구
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1992년도 춘계학술대회 논문집
    • /
    • pp.86-90
    • /
    • 1992
  • We have studied the characteristics of n-and p-channel FETs with submicron channel length fabricated by twin-well process. Threshold voltage variation and potential distribution with channel ion implantation conditions and impurity profile of n-and p-channel region wee simulated using SUPREM-II and MINIMOS 4.0 simulater, P-channel FET had buried-channel in the depth of 0.15 $\mu\textrm{m}$ from surface by counter-doped boron ion implantation for threshold voltage adjustment. As a result of device measurement, we have obtained good drain saturation characteristics for 3.3 [V] opreation, minimized short channel effect with threshold voltage shift below 0.2[V], high punchthrough and breakdown voltage above 10[V] and low subthreshold value.

  • PDF