• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.225-230
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• 2002

중부 옥천대 구룡산층 분포지역에서, 채석장 지류는 특징적으로 낮은 pH와 높은 EC를 나타내는 산성광산폐수의 형태를 보이고 있었으며, 황갈색 철 침전물을 나타내고 있었다. 이들은 탄산염이 풍부한 화전리층(상층) 지류와의 혼합으로 백색 알루미늄 침전물을 형성시켰으며, 따라서 산성수의 영향 범위가 크게 나타나지 않는 것으로 확인되었다. 포화지수와 열역학 데이터를 이용한 결과, 본 연구지역 채석장 지류에 황갈색 침전물을 생성시키는 용존철은 래피도크로사이트와 침철석의 복합적인 작용에 의해 농도가 조절되고 있음을 확인하였다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 한국화재소방학회 2002년도 추계학술대회논문집
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• pp.358-374
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• 2002

최근 빈번하게 발생하고 있는 사우나 등의 열을 방사하는 도크내에서 발생하는 화재사고는 다중이용업소를 이용하는 불특정한 사람들의 생명을 위협하고 있는 수준에 도달하고 있다. 특히 이런 시설의 화재는 화재발생 후에 소방대에 의한 진압에만 치중하고 있어 향후 계속하여 화재가 발생할 우려가 큼에도 불구하고 착화원인을 규명하는데 소홀히 하고있다. 특히 현장감식에 의한 육안조사만을 실시하여 화재원인을 추정하거나 설정하는 경우가 대부분이라 근본적인 대책을 세우지 못하고 있다. 따라서 본 연구에서는 육안조사 등에 의하여 설정한 착화원인을 과학적인 분석법 즉, EU국가에서 널리 사용하는 CFD(컴퓨터수치해석)시뮬레이션 S/W를 사용하여 연소모델링에 의한 검증조사기법을 적용하여 원인을 검증하는데 사용하여 국내화재조사기술의 과학화를 시도하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.245-249
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• 2004

This paper deals with two most important problems, from both practical and theoretical standpoints, arising when building the ships in docks. Such docks have become core components of modern ship construction. One problem is to minimize the number of building docks in the shipyard, while the other is to keep the usage rate of resources fed into dock as constant as possible. In this paper the combined problem is formulated as a single-integer programming model. The LP-relaxation of this model is solved by column-generation techniques. The results of an experimental evaluation show that the lower bounds are tight. Practical applications of this formulation are also discussed.

• Journal of Intelligence and Information Systems
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• 제2권1호
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• pp.59-73
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• 1996

전체적인 조선 생산일정계획을 수립하기 위해서 계층적 구조를 채택하였다. 이 구조에 의하면 도크의 상위 일정계획 생성기는 탑재 일정계획을 생성하고, 조립공정의 하위 일정계획 생성기는 상위 일정계획 생성기가 요구하는 범위 내에서 각각 세부적인 조립 일정계획을 세우게 된다. 그런데 하위 일정계획 생성기가 아무리 노력하여도 상위 일정계획 생성기로부터의 제약조건을 만족시킬 수 없는 상황이 발생하면, 일정계획 수정기에 통보하여 초기 탑재 일정계획을 수정해야 한다. 하위 일정계획 생성기로부터의 조정요청을 반영하기 위해서 부분 수정을 통해 충격을 최소화시키는 일련의 휴리스틱으로 구성된 알고리즘을 제시하였다. 각각의 휴리스틱은 여유시간 제거, 버퍼 제거, 작업시간 축소, 다단계 여유시간 제거, 과부하 자원 공유블럭 조정, 자원 제약조건 완화 등이고, 흡수되지 않은 일부의 충격은 주변으로 전파된다. 이와같은 방법론을 대우조선의 상황에 적용하여, 조선일정계획 수정 시스템인 DAS-REACT를 개발하였다.

• Journal of the Korean Society of Marine Environment & Safety
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• 제28권1호
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• pp.153-160
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• 2022

This study presents the bogie arrangement of the load-out system for on-ground shipbuilding. The load-out system is one of the most important systems to perform the bogie arrangement of the on-ground shipbuilding technique without dry dock facilities, and this system is composed of four pieces of equipment: bogies, driving bogie with motors, trestles, and power packs. Also, the bogie arrangement analysis (BAA) is employed to simply calculate the reaction forces at the trestle for structural safety. In this context, the purpose of this study is to propose an optimal design method to perform the bogie arrangement satisfying structural safety requirements with minimal cost. It is expected that the proposed methodology will contribute to the effective practice as well as to the improvement of competitive capability for shipbuilding companies at the on-ground shipbuilding stage. Furthermore, we describe some problems and their solutions of the deformation that may occur in the bottom of the hull during the load-out process. As a result, it is shown that we applied it to the 114K crude oil tanker (Minimum bogie 54EA) and the 174K CBM LNG carrier (Minimum bogie 88EA), it can minimize the number of bogie and critical risks (Safety rate 1.61) during the load-out of on-ground shipbuilding. Through this study, the reader will be able to learn successful load-out operation and economic shipbuilding in the future.

• Journal of Korea Port Economic Association
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• 제38권3호
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• pp.69-86
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• 2022

This study analyses the necessity of the large-size shipyard and explores competitiveness factors of it. Furthermore, the competitiveness is evaluated and the economic feasibility of building and operation of shipyard is examined. As a result of AHP analysis of the determining factors of the competitiveness of the repairing shipyard, the importance of the factors was found in the order of arrival and departure safety, repair technology, dock and wharf facilities, repair cost, repair period (on time delivery), and repair parts supply. Moving distance, repair service quality, repair parts supply, arrival and departure safety, repair technology, dock and quay wall facilities, and repair period (on time delivery) were identified as key factors in the AHP analysis for competitiveness of the Busan Port repair shipyard to be built in the future. As a result of the analysing economic feasibility, the net present value of the Busan Port repair shipyard construction and operation investment project was KRW 435.6 billion, and the internal rate of return was 9.8%, higher than the social discount rate (4.5%), and the cost-benefit ratio (B/C) was high at 1.167. As a result of the study, the necessity and economic feasibility of the Busan Port repair shipyard are sufficiently ensured, and the competitiveness assessment was highly positive.

• Journal of Advanced Marine Engineering and Technology
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• 제36권2호
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• pp.250-257
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• 2012

Currently, large vessels and structures are manufactured into set of blocks, then assembled on-site. Large scale ships that weigh thousands of tons are built in a short period by making set of large blocks and assembled on a dock or a land. When a transporter encounters a slope during the process of transporting blocks, the heavy goods loaded on the transporter can be tilted. Further, if the vehicle moves down the slope in this state then it can cause an accident of overturn of loaded goods. The research has been taken into account to calculate the center of gravity of the transporter carrying heavy objects on a leveled surface or the three dimensions. In addition, ZMP (Zero Moment Point) is used to calculate the allowable slope degree that objects are predicted to overturn. Through the simulation, the objects' stability is tested when it is climbing the slope.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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• pp.1586-1591
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• 2006

조선사는 선주와의 계약에 의한 수주 생산방식으로 계약시 명시된 작업시작일, 도크작업시작일 진수일, 인도일을 지키기 위한 공정별 목표 생산완료일을 결정하게 되고, 각 공장별로 목표 생산완료일을 지키기 위한 일정계획을 수립하게 된다. 생산되는 선박은 선종, 선형에 따라 구성되는 블록의 수가 다르고 그 형태도 매우 다양하다. 그러므로 선박을 건조하기위해 제작되는 블록의 정확한 작업공기와 공수를 예측하기가 매우 어렵다. 본 논문에서는 불확실한 작업공기와 공수를 이용하여 작업장의 공간제약을 고려한 일정계획을 수립하는 문제에 대하여 기존의 공간제약 문제에 대한 연구에서 나아가 실행 단계에서의 운영프로세스를 개선하여 적용하는 연구를 수행하였다. 이번 연구의 결과로 목표 생산계획과 부서계획, 실행 실적을 과거 데이터와 비교분석 하여 개선된 운영프로세스의 효과를 검증하였다.

• Journal of Ocean Engineering and Technology
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• 제23권1호
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• pp.104-108
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• 2009

As the demands of ocean resource development increase, many offshore structures are required. To cope with the active ocean developments, many types of construction methods have been applied for offshore facilities, including oil, gas and harbors. One of the challenges is to transport and install the heave bridge caisson. Several construction methods are well understood. However, for the sake of safety and reliability, the F/D installation method can be utilized. While the caisson is carried by an F/D, the mooring force of the tug boat and the structure stability from exiting motions in the dock should be checked against external loadings and sea conditions. The external loads can be classified with wind force, current force, and wave force. In the stability analysis, transportation velocity and draft of F/D are important factors. The dynamic stability and hook load for crane barge installation for the same caisson are also studied. Considering external loads and dominant factors, the stability of caisson during transportation has been investigated.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 한국항해항만학회 2013년도 춘계학술대회
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• pp.132-133
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• 2013

Ship salvage crane is to salvage the equipment safely, this type of crane in the shipyard's large ships or port is being used a lot of container etc. Such a salvage crane was installed on the land and it is built to use the harbour facilities. In this paper, the response amplitude operator and the wave exiting force of floating type salvage crane is calculated and it is performed to structural response estimation.