• Journal of the Korean Institute of Gas
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• v.28 no.2
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• pp.93-104
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• 2024

Facility diagnosis is essential for the smooth operation and life extension of rotating equipment used in industrial sites. Compared to other diagnostic methods, vibration diagnosis can find most of the initial defects, such as unbalance, alignment failure, bearing defects and resonance, compared to other diagnostic methods. Therefore, vibration analysis is the most commonly used facility diagnosis method in industrial sites, and is usefully used as a predictive preservation (PdM) technology to manage the condition of the facility. However, since the vibration diagnosis method is performed based on experience based on the standard, it is carried out by experts. Therefore, it is intended to contribute to the reliability of the facility by establishing a system that anyone can easily judge defects by establishing a vibration diagnosis method performed based on experience as a knowledgeable code system. An algorithm was developed based on the ISO-20816 standard for vibration measurement, and the reliability was verified by comparing the results of vibration measurement at various demonstration sites such as petrochemical plant compressors, hydrogen charging stations, and industrial machinery with the results of analysis using a development system. The developed algorithm can contribute to predictive maintenance (PdM) technology that anyone can diagnose the condition of the rotating machine at industrial sites and identify defects early to replace parts at the exact time of replacement. Furthermore, it is expected that it will contribute to reducing maintenance costs and downtime due to the failure of rotating machines when applied to various industrial sites such as oil refining facilities, transportation, production facilities, and aviation facilities.

• Journal of Information Technology and Architecture
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• v.11 no.1
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• pp.1-10
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• 2014

From 2004 to 2013, the annual investment for the ICT sector in Korea amounted to about 3.2 trillion won. Depending on whether the government policy allowed for budget increases and/or decreases, this impacted the investment in the ICT sector. In particular, the fixed costs of operation and maintenance lead to a reduced chance for a new potential demands in IT programs. Even though a situation may exist that there are insufficient funds available, there is a need for building a sustainable long-term IT investment management system. The purpose of this study is to conduct basic research for the arrangement of preparation to meet IT needs required in the public sector. For this, this paper introduces the concept of IT Investment Management based on prudent forecasting. After both foreign and domestic relevant cases are reviewed, implications will be derived from the aforementioned cases. Through this process, the direction of IT Investment Management based on forecasting for the IT projects decision making will be suggested. These research results could be used for helping to develop better policies and a more efficient management of the public sector IT budget.

• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.115-122
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• 2010

The importance of the life cycle cost (LCC) analysis for bridges has been recognized over the last decade. However, it is difficult to predict LCC precisely since the costs occurring throughout the service life of the bridge depend on various parameters such as design, construction, maintenance, and environmental conditions. This paper presents a methodology for the optimal life cycle cost design of a bridge. Total LCC for the service life is calculated as the sum of initial cost, damage cost, maintenance cost, repair and rehabilitation cost, user cost, and disposal cost. The optimization method is applied to design of a bridge structure with minimal cost, in which the objective function is set to LCC and constraints are formulated on the basis of Korean Bridge Design Code. Initial cost is calculated based on standard costs of the Korea Construction Price Index and damage cost on damage probabilities to consider the uncertainty of load and resistance. Repair and rehabilitation cost is determined using load carrying capacity curves and user cost includes traffic operation costs and time delay costs. The optimal life cycle cost design of a bridge is performed and the effects of parameters are investigated.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.41-48
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• 1988

Fatigue phenomena usually occur in the structures such as bridges subjected to repeated loading with increasing service year. Especially, applied stresses happen to approach to design values due to rapid increase of traffic volume and vehicle weight, so it gives serious effects to the stability of bridges. Therefore, in this paper, the data for load carrying capacity of bridges obtained from field tests were analysed statistically to investigate bridge behaviour and a basic approach to estimate the impact factor was proposed after a comparison war made between field-test data and the calculated values obtained by using matrix structural analysis method.

• 한국공간정보시스템학회:학술대회논문집
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• 2001.11a
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• pp.287-303
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• 2001

지리정보의 중요성이 널리 인식되고 사회 각 분야에서 지리정보에 대한 수요가 날로 증가되고 다양해지고 있지만 GIS의 개발, 설치, 유지, 보수의 어려움에 따른 고가의 비용과 시장에 대한 적응력부족으로 GIS의 광범위한 활용이 저해 받고 있는 실정이다. 또한, 개인을 위한 GIS 서비스나 응용프로그램의 하나의 기능 컴포넌트로서의 GIS 서비스가 GIS의 주류로 발전할 것으로 예측되고 있지만 이를 지원하기 위한 GIS 개발, 배포 모델과 기반기술이 결여되어 있다. 그러나, 사용자가 월 정액요금을 지불하고 인터넷 또는 인트라넷을 통하여 ASP (Application Service Provider)에 의해 원격 중앙 서버에 설치, 관리되고 있는 소프트웨어 응용프로그램을 사용하는 형식은 혁신적인 소프트웨어 개발과 배포 모델로서 차세대 컴퓨터 환경의 기초로 각광 받고 있으며 이를 GIS에 적용할 때 GIS의 광범위한 응용과 원활한 유통을 크게 추진할 것으로 기대된다. 그러므로, 현시점에서 GIS ASP를 위한 합리적인 모델과 이에 근거한 소프트웨어 플랫폼에 대한 연구와 개발이 절실히 필요하다. 본 논문에서는 ASP 환경 하에서 더욱 신속하고 편리한 GIS 개발, 통합, 배포를 가능하게 하고 보다 나은 질의 GIS ASP 서비스를 제공하기 위하여 마이크로소프트의 ASP 플랫폼인 .NET 기반의 3 계층 GIS ASP 모델을 중심으로 하는 GIS ASP 소프트웨어 플랫폼의 설계를 제시하였다.

• The magazine of the Korean Society for Advanced Composite Structures
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• v.5 no.3
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• pp.38-52
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• 2014

도시주민생활에 없어서는 안 될 주요한 사회간접자본시설인 하수도, 하수도처리시설 등의 콘크리트 구조물에 대한 부식열화는 현재 세계 각국에서 급속히 진행되고 있다. 콘크리트 구조물은 반영구적인 것으로 인식하고 있다. 그러나 각종 열화 인자에 의해 구조물의 사용수명은 급속히 단축된다. 하수시설 내에서는 황산이외에도 다양한 염류에 의하여 콘크리트구조물이 부식될 가능성이 있지만 황산에 의한 부식이 가장 대상범위가 넓고 부식속도가 빠르기 때문에 부식현상이 발견되면 급속하고 적절한 대응조치가 필요하다. 열화예측결과 및 구조물의 공용연수를 감안한 신뢰성이 높은 공법의 도입이 필요하며 이러한 조건에 적합한 유기재료와 무기재료의 복합 특성을 발휘하는 갱생공법에 사용되는 주요 소재의 실험적 특성에 관하여 고찰하였다. 그 결과 경질염화비닐(이하 프로파일)은 내외수압 저항성에서 3분간 $1kgf/cm^2$의 압력에도 누수 및 압력의 이동이 없었으며 약품침지에 따른 중량변화량이 $0.2mg/cm^2$이하로 산에 대한 변화량은 거의 없었다. 주입재인 모르타르의 산성에 대한 저항성은 일반 콘크리트에 비해 우수하였으며 기존 모르타르에 비해 비확선성 또한 우수하였다. 장거리압송시험은 200m까지 안정적인 압송이 가능하여 이 기술에 필요한 요구 성능을 확보한 것으로 나타났다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.11
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• pp.2176-2181
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• 2011

This paper estimates the life cycle cost(LCC) of a propulsion control system using the maintenance information in the high speed train(KTX-1). Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Until now, most life cycle cost of the system has been studied as a whole system viewpoint. But in case of railway industry, LCC studies are needed on the subsystem like a propulsion control system because subsystems are developed continuously localization. This paper proposes the life cycle cost model which fitted to estimate life cycle cost (LCC) using maintenance information manual. As a result, LCC on propulsion control system increased moderately expect for periodical time when major parts are replaced at the same time. Results will be reflected in the development of domestic products.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06b
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• pp.112-114
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• 2006

최근 영상 인식 정보를 서비스 로봇 도메인에서 사용하기 위한 연구와 함께 전통적인 영상 인식 방법의 성능을 높이기 위한 연구가 진행되고 있다. 기존의 방법들은 기하학적 모델을 기반으로 예측 가능한 환경에서 상황을 인식하였기에 이를 실내 환경과 같은 동적인 환경에 적용하는 것은 정확도나 인식의 효율 면에서 한계를 갖는다. 이에 지식 기반 접근 방법을 통해 정확도를 항상 시키거나 계산 비용을 감소시킴으로써 영상 인식성능을 높이기 위한 다양한 연구가 있어 왔다. 본 논문에서는 서비스 로봇이 물체를 탐색할 때, 대상 물체가 다른 물체에 의해 가려짐으로써 발생하는 불확실한 상황을 해결하기 위한 방법을 제안한다. 제안하는 방법은 발견된 물체를 컨텍스트 정보로 사용하여 대상 물체의 존재 여부를 추론하며, 이를 위해 신뢰도를 모델링할 수 있는 확률적 모델인 베이지안 네트워크와 도메인 지식을 모델링 할 수 있는 온톨로지를 함께 사용한다. 효과적인 모델링을 위해 본 논문에서는 기본적인 물체 관계를 모듈화 하여 설계하기 위한 베이지안 네트워크 구조와 확률 값 선정 방법. 이들을 온톨로지를 기반으로 주어진 상창에 따라 결합하는 방법을 제안한다. 이는 물체 관계를 모델링할 때 발생하는 중복 설계를 감소시켜주고 유지 및 보수를 용이하게 한다. 설계된 추론 모듈은 실험 결과 5가지 장소에서 높은 정확도를 보여주었다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.2
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• pp.288-292
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• 2013

This paper presents the result of life-cycle cost (LCC) estimation for domestic products propulsion control system (motor block unit) of KTX-1 considering periodic maintenance. Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Life cycle costing includes the cost of concept design, development, manufacture, operation, maintenance and disposal. To estimate LCC for domestic products motor block unit, it was analyzed physical breakdown structure (PBS) on motor unit in view of maintenance cost and unit cost etc. As a results, life cycle cost on motor block unit increased moderately expect for periodical time when major parts are replaced at the same time. hereafter this results will be reflected in the domestic products being developed.

• Journal of Digital Convergence
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• v.19 no.8
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• pp.249-255
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• 2021

This study proposed a method for determining weights for the eight quality characteristics, such as functionality, reliability, usability, maintainability, portability, efficiency, security, and interoperability, which are suggested by international standards, focusing on software test reports. Currently, the test results for software quality evaluation apply the same weight to 8 quality characteristics to obtain the arithmetic average. Weights for 8 quality characteristics were applied using the results from text analysis, and weights were applied using the results of text analysis of test reports for two products. It was confirmed that the average of test reports according to the weighted quality characteristics was more efficient.