• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.115-121
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• 2013

A number of urban renewal projects are currently being implemented around the world. Current project management tools are limited in effectively dealing with numerous issues regarding management of these projects (e.g., simultaneous execution of multiple projects). As an effort to address this deficiency, an Intelligent Program Management Information System (i-PgMIS) was developed for effective management of urban renewal projects. The i-PgMIS is a web-based system consisting of various modules including cost management, schedule management, risk management, change management, eco-value engineering (EVE) and so on. Based on the recognition of increasing awareness of creating sustainable built environment, this paper focuses on the EVE module that can support eco-value analysis at program-level management. The EVE module is expected to enhance value and sustainability of construction processes throughout the whole 'program' lifecycle and further to support program feasibility study based on life cycle costing.

• 융합보안논문지
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• 제19권2호
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• pp.163-174
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• 2019

RAM 분석은 무기체계의 개발 목표를 제시함으로써 투입되어야 하는 재원의 범위를 결정짓는데, RAM 분석이 제대로 되지 않을 경우 사업비용의 막대한 증가를 초래할 수 있다. 개념연구 단계에서의 누적비용비율은 총 비용대비 1%미만이지만 총 수명주기비용의 65-70%가 결정되므로 탐색개발 전 단계까지 RAM 분석이 매우 중요하다. 새로운 기술에 기반한 신규 무기체계를 기존 방식의 OMS/MP로 작성하여 RAM 목표값을 산출하면, 미래 전장에서 적용될 신규 기능의 반영이 어렵다는 제한 사항이 있다. 따라서 본 논문은 무인전투차량의 사례를 중심으로 델파이기법과 베이지안 이론을 토대로 신규 기능을 반영한 인수를 도출하여 OMS/MP를 작성하는 방법을 제시한다.

• 한국건설관리학회논문집
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• 제20권5호
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• pp.21-30
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• 2019

최근 전 세계적으로 지구온난화에 따른 이상기온과 화석연료 고갈 등 환경과 에너지문제는 인류의 생존을 위협하는 중대 과제로 대두되고 있다. 이에 따라 건축물 에너지 절감 및 온실가스 감축에 획기적으로 기여할 수 있는 혁신적인 건축물로서 제로에너지빌딩에 대한 관심이 높아지고 있다. 그러나 시장에서는 추가되는 건설비용은 제로에너지 인증 활성화에 큰 걸림돌이 되고 있다. 본 연구에서는 일반적인 민간 분양아파트를 연구의 대상으로 선정하고 초기 설계단계부터 제로에너지 인증을 위한 세부 요소들을 친환경주택 건설기준에 근거하여 제시하였으며, 인증 세부요소들의 비용효율분석을 통해 적정 가산비용을 제시하였다. 아직까지 기술수준과 물리적인 한계로 인하여 공동주택에서는 3등급까지만 인증이 구현 가능 한 것으로 분석되었다. 또한 생애주기동안 비용추이를 검토해본 결과 아직까지 제로에너지빌딩 5등급의 경우에서만 준공 후 13년 이내 모든 비용의 회수가 가능한 것으로 검토되었다. 앞으로 발주예정인 공동주택 사업 검토 시 본 연구에서 제시된 추가사업비가 적절히 반영되어 제로에너지빌딩 인증 활성화에 기여하고자 한다.

• Structural Engineering and Mechanics
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• 제63권6호
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• pp.703-712
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• 2017

The composite blades of offshore wind turbines accumulate structural damage such as fatigue cracking due to harsh operation environments during their service time, leading to premature structural failures. This paper investigates various fatigue crack models for reproducing crack development in composite blades and proposes a stochastic approach to predict fatigue crack evolution and to analyse failure probability for the composite blades. Three typical fatigue models for the propagation of fatigue cracks, i.e., Miner model, Paris model and Reifsnider model, are discussed to reproduce the fatigue crack evolution in composite blades subjected to cyclical loadings. The lifetime probability of fatigue failure of the composite blades is estimated by stochastic deterioration modelling such as gamma process. Based on time-dependent reliability analysis and lifecycle cost analysis, an optimised maintenance policy is determined to make the optimal decision for the composite blades during the service time. A numerical example is employed to investigate the effectiveness of predicting fatigue crack growth, estimating the probability of fatigue failure and evaluating an optimal maintenance policy. The results from the numerical study show that the stochastic gamma process together with the proper fatigue models can provide a useful tool for remaining useful life predictions and optimum maintenance strategies of the composite blades of offshore wind turbines.

• 한국건설관리학회논문집
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• 제3권4호
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• pp.132-138
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• 2002

최근 건설시장의 선진화를 목적으로, 주어진 공기 내 완공 및 비용절감, 품질향상 등을 위하여 PMIS(사업관리정보시스템)의 활용이 심도 있게 요구되고 있다. 하지만, 현재 각 프로젝트에서 개발된 PMIS는 개발기간의 한시성으로 대개 공사현황위주로 되어 있고, 프로젝트 수행자들의 PMIS사용 역시 형식적으로 운용됨으로써, 발주자, 사업관리자, 시공자간의 효율적인 의사소통에 한계가 있는 실정이다. 이에 현재까지 개발된 사업관리정보시스템을 검토하고, 그동안 현업에서 개발한 경험을 토대로 효율적 인 PMIS의 구축방향을 제시코자 한다.

• KIEAE Journal
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• 제15권3호
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• pp.15-20
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• 2015

Purpose: Suggesting a working prototype of a kinetic light shelf unit and revealing its energy efficiency by a series of building performance simulations were presented. Recently, kinetic building envelope has been an emerging technology as an innovative way to control exterior building environment, but products from many researches about the facade could not been reached to the industrialization so far. That is because its initial installation, operation and maintenance costs are still too high to use for the practical field, although buildings using kinetic envelopes could decrease their energy consumption significantly. This narrow point of view needs to be reconsidered, since buildings require great amount of energies to run their functions through the whole life and using better building components can lead to achieve much more benefits in aspects of the lifecycle cost (LCC). Method: A series of certified simulation tools like Ecotect and Green Building Studio that are normally used for researches and developments in the field of architecture were utilized. Result: Based on simulation analyses, the result of the study has showed that the proposed system definitely has adaptability to the professions and positively shows practicability as advanced integrative building envelopes with renewable energy association.

• Wind and Structures
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• 제22권1호
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• pp.107-131
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• 2016

The need for a more affordable, reliable, clean and secure energy has led to explorations in non-traditional sources, particularly renewable energies. Wind is one of the cleanest energy sources that plays a significant role in augmenting sustainability. Wind turbines, as energy convertors, are usually tall and slender structures, and depending on their location (inland or offshore), they can be subject to high wind and/or strong wave loadings. These loads can cause severe vibrations with detrimental effects on energy production, structural lifecycle and initial cost. A dissipativity analysis study was carried out to know whether wind turbine towers require damping enhancement or rigidity modifications for vibration suppression. The results suggest that wind turbines are lightly damped structures and damping enhancement is a potential solution for vibration lessening. Accordingly, the paper investigates different damping enhancement techniques for vibration mitigation. The efficacy of tuned mass damper (TMD), tuned liquid column damper (TLCD), tuned sloshing damper (TSD), and viscous damper (VD) to reduce vibrations is investigated. A comparison among these devices, in terms of robustness and effectiveness, is conducted. The VD can reduce both displacement and acceleration responses of the tower, better than other types of dampers, for the same control effort, followed by TMD, TSD, and finally TLCD. Nevertheless, the use of VDs raises concerns about where they should be located in the structure, and their application may require additional design considerations.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.47-48
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• 2012

In this study, the CO₂ emission and economic efficiency of high-rise apartment houses were evaluated, and were analyzed as a way to establish database on the evaluation of environment-friendliness of high-rise buildings. To that end, standard of buildings to be evaluated were proposed through analysis of the designing guideline for high-rise apartment houses proposed by Seoul city, and CO₂ emission of the subject buildings were evaluated based on the characteristics of materials admitted into each building and the amounts of energy consumed during lifecycle period. In addition, the initial costs in construction stage and annual costs in operation stage were set as analysis parameters, and along with calculation of direct cost by the consumption of construction materials and energy, the costs of CO₂ emission were evaluated and analyzed. As a result, the CO₂ emission and economic efficiencies of high-rise apartment houses by construction stage and operation stage could be analyzed quantitatively.

• 한국분말재료학회지
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• 제27권3호
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• pp.256-267
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• 2020

Metal additive manufacturing (AM) technologies are classified into two groups according to the consolidation mechanisms and densification degrees of the as-built parts. Densified parts are obtained via a single-step process such as powder bed fusion, directed energy deposition, and sheet lamination AM technologies. Conversely, green bodies are consolidated with the aid of binder phases in multi-step processes such as binder jetting and material extrusion AM. Green-body part shapes are sustained by binder phases, which are removed for the debinding process. Chemical and/or thermal debinding processes are usually devised to enhance debinding kinetics. The pathways to final densification of the green parts are sintering and/or molten metal infiltration. With respect to innovation types, the multi-step metal AM process allows conventional powder metallurgy manufacturing to be innovated continuously. Eliminating cost/time-consuming molds, enlarged 3D design freedom, and wide material selectivity create opportunities for the industrial adoption of multi-step AM technologies. In addition, knowledge of powders and powder metallurgy fuel advances of multi-step AM technologies. In the present study, multi-step AM technologies are briefly introduced from the viewpoint of the entire manufacturing lifecycle.

• Industrial Engineering and Management Systems
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• 제15권4호
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• pp.290-297
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• 2016

The successful transfer of technology, needs to recognize the industrial purposes, resources, technology, innovation and the mode of transmission, methods of transmission, influential factors, it's how to recruit and how to develop, and each of these cognitive relies on special expertise. One of the important technologies is automotive technology, and s technology is important for the transition and its development in recent years. Hence, in this paper, after studying Iran and the world's automotive and emerging technologies situation, the status of commercial vehicles and s technology model are studied based on external models, technical specifications, and cost. In this way, we examine the incidence and the applicability of the technology used in the production of heavy-duty vehicles, in recent years, with the passage of time, and we examine the technology lifecycle, from the perspective of physical characteristics and technical features. The results show that the technology of the studied heavy-duty vehicles (Titan) is close to the time of his fall, because spending puberty, so, according to the investigation of new technologies, we should strive to create changes in vehicle technology.