• 한국시뮬레이션학회논문지
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• 제21권1호
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• pp.1-8
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• 2012

최근들어, 글로벌 조선소들은 친환경 선박 건조와 환경 친화적 생산 공정에 큰 관심을 보이고 있다. 이러한 추세에 따라 이 연구는 조선소 레이아웃에 전 과정 평가를 적용하는 연구를 수행하였다. 전 과정 평가는 제품과 시스템의 전수명주기와 관련된 환경적 영향을 평가하는 기법으로 특정 산업분야에서 ISO 14040 표준에 따라 적용연구가 수행되고 있다. 전 과정 평가를 조선소 레이아웃에 적용하기 위해 조선소 레이아웃 계획 프레임워크를 분석하고, 조선소 레이아웃에 대한 목록분석을 수행하였으며, 환경적 영향에 대한 이산 사건 시뮬레이션 모델을 구축하였다.

• 한국해양공학회지
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• 제11권3호
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• pp.191-199
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• 1997

This paper develops the piece creation of Hull-structure using PC(Personal Computer) which is from CADRA of graphic program. Large-sized shipbuilding yard was carried out on the development of CNC(Computer Numerical Control) auto cutting system used in super S/W such as AUTODEF, TRIBON. But this system needs lots of expenses and high technician, and only used in large-sized shipbuilding yard, not medium-sized and small-sized shipbuilding yard. To bring up the small and medium-sized ship building yard lacking a little competitive power. Small and medium-sized shipbuilding yard need the piece creation of Hull Structure S/W which is joined with the CADRA. Therefore the piece creation of Hull-Structure S/W is developed to joined with the CADRA of graphic S/W to create the piece to be needed on as auto cutting process using PC.

• Journal of Welding and Joining
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• 제16권3호
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• pp.102-110
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• 1998

The horizontal fillet welding is prevalently used in heavy and ship building industries to fabricate the large scale structures. A deep understanding of the horizontal fillet welding process is restricted, because the phenomena occurring in welding are very complex and highly non-linear characteristics. To achieve the satisfactory weld bead geometry in robot welding system, the seam tracking algorithm should be reliable. The number of seam tracker was developed for arc welding automation by now. Among these seam tracker, the arc sensor is prevalently used in industrial robot welding system because of its low cost and flexibility. However, the accuracy of arc sensor would be decreased due to the electrical noise and metal transfer. In this study, the signal processing algorithm based on the neural network was implemented to enhance the reliability of measured welding current signals. Moreover, the seam tracking algorithm in conjunction with the signal processing algorithm was implemented to trace the center of weld line. It was revealed that the neural network could be effectively used to predict the welding current signal at the end of weaving.

• 건축역사연구
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• 제26권4호
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• pp.19-34
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• 2017

The purpose of this study was to comprehend the assignment and the procurement method of wood works' craftsman through the Salleung-dogamuigwes in royal tombs constructions in the late Joseon period. Following conclusions have been reached through the study. First, Carpenter and other nine craftsmen were introduced in carpentry works. The craftsmen were put in by occupation to maintain the quality of the government building construction by wood processing area. It was distinguished by frame member, Sujangjae, window framing wood, decorative member. Second, sawyer showed a sharp increase in the latter half of the 18th century and declined since the middle of the 19th century. This is closely related to the increase in demand for building materials and the growth of civilian wood products. As a maximum of 300 people have been assigned to the craftsmen in the woodwork, it can be seen that the work has been divided by the process. Third, the national carpenter was difficult to procure from the 17th century to the beginning of the 18th century. From the middle 18th century, the system procuring national carpenter was stabilized. In the 19th century, the input ratio of the national craftsmen seems to have decreased significantly and seems to have kept it at the minimum level. Forth, sawyer were procured through Seongonggam from the late 18th century through the mid 19th century. That means that the role of the sawyer had become important. Since Jogakjang is not a necessary manpower, it usually has civilian artisans.

• 제어로봇시스템학회논문지
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• 제8권9호
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• pp.776-787
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• 2002

Automation of welding process in shipyards is ultimately necessary, since the welding site is spatially enclosed by floors and girders, and therefore welding operators are exposed to hostile working conditions. To solve this problem, a welding mobile robot that can navigate autonomously within the enclosure has been developed. To achieve the welding task in the closed space, the robotic welding system needs a sensor system for the working environment recognition and the weld seam tracking, and a specially designed environment recognition strategy. In this paper, a three-dimensional laser vision system is developed based on the optical triangulation technology in order to provide robots with 3D work environmental map. Using this sensor system, a spatial filter based on neural network technology is designed for extracting the center of laser stripe, and evaluated in various situations. An environment modeling algorithm structure is proposed and tested, which is composed of the laser scanning module for 3D voxel modeling and the plane reconstruction module for mobile robot localization. Finally, an environmental recognition strategy for welding mobile robot is developed in order to recognize the work environments efficiently. The design of the sensor system, the algorithm for sensing the partially structured environment with plane segments, and the recognition strategy and tactics for sensing the work environment are described and discussed with a series of experiments in detail.

• 플랜트 저널
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• 제13권2호
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• pp.39-45
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• 2017

본 논문은 시스템엔지니어링기법을 이용하여 해양플랜트 산업의 소형 유틸리티 장비의 입찰단계에서 사용가능한 FEED 검증 수행모델에 대한 연구이다. 현재 국내 해양플랜트 기자재산업계는 해양플랜트에 진출하면서 프로젝트 수행에 따른 재정적 위험에 직면한 상태이며, 그 주요한 원인으로 기자재업체의 발주처(COMPANY 또는 EPC: Engineering, Procurement and Construction) 로부터 제공받은 FEED 결과물에 대한 검증능력부족으로 조사되었다. 이에 요구사항 분석, 기능, 성능분석 및 물리적아키텍처 구축프로세스를 순차적으로 적용하는 시스템 엔지니어링 기법을 간략화 한 FEED 설계 검증방법을 제안하고 이를 소형 유틸리티 장비(Air Compressor)를 대상으로 기존의 경험에 의존한 검증방법과 개발한 FEED 검증 모델을 적용한 결과를 비교함으로써 개발된 모델의 사용적정성을 검증하였다.

• 한국기계가공학회지
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• 제20권1호
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• pp.80-87
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• 2021

Most container ships are currently being constructed as Ultra-Large Container Ships. Hence, the equipment of the ships is also becoming relatively large. In particular, propellers, rudders, and rudder stocks are large in the stern structure, and in relation, efficient design of the hull structures to safely secure these parts is important. The bottom shell plate surface of a stern skeg is a perforated plate from which the rudder stock penetrates, so it is an important component for the stern structure. In this paper, to determine the critical buckling of the shell plate, an interaction curve equation for the two-axis compression of the shell plate was derived using the maximum value of the static structural stress multiplier in a load multiplier mode. This equation predicts the timing of the buckling occurrence. By analyzing this interaction curve equation, the buckling behavior of the plates subjected to a combination load was determined and the usefulness of applying it to ship building was investigated.

• 한국환경보건학회지
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• 제33권6호
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• pp.506-512
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• 2007

This study was conducted to describe the exposure levels of welding fumes by the type of manufacturers, work process, welding type and the size of manufacturers, and to find out the trend of chronological changes of airborne welding fume levels. The subjects of this study were 509 manufacturers, consisting of 11 types of manufacturers, 3 work processes, 7 welding types, in Busan from January, 1997 to December, 2005. Airborne concentration of welding fume was determined by manual of National Institute for Occupational Safety and Health (NIOSH), and the data were analyzed by using SPSS 10.0 for Windows program. The mean concentration of airborne welding fume in all manufacturers was $1.29\;mg/m^3$ (Range: $0.01{\sim}3.00\;mg/m^3)$. The level of welding fume was the highest, as $1.96\;mg/m^3$, for manufactures of motor vehicles, trailers and semi-trailers, which was lower than $5.0\;mg/m^3$ of 8 hr-TWA in Korean permissible exposure limit for welding fume. There was a significant difference in the mean levels of welding fumes by work process, showing the highest in welding workshop ($1.39\;mg/m^3$), followed by pipeline welding workshop ($1.26\;mg/m^3$) and engineering workshop ($1.20\;mg/m^3$). Among welding types, the mean level of welding fume was the highest in the type of $CO_2$ & arc welding, as $1.46\;mg/m^3$, followed by $CO_2$ welding ($1.40\;mg/m^3$), shielded metal arc welding ($1.31\;mg/m^3$), spot welding ($1.27\;mg/m^3$), and so on. The highest mean level of welding fume was $1.58\;mg/m^3$ in work process of pipe line welding workshop for the manufacturers of basic iron and steel, and $2.27\;mg/m^3$ in the type of arc welding for the manufactures building ship and boats. By the size of manufacturers, the mean concentration of welding fume for manufactures in small scale with less than 50 workers was the highest as $1.45\;mg/m^3$ (Range: $0.07{\sim}3.00\;mg/m^3)$. The mean level of welding fume was the highest as $1.39\;mg/m^3$ both in 1997 and in 2005, showing a trend of fluctuating periodically within a range of $1.10{\sim}1.39\;mg/m^3$. The above results suggested that more effective control program for work environment producing welding fumes should be developed and applied since there were significant variations in welding fume levels by the type of manufacturers, work processes, welding types, the size of manufactures, and by year.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권2호
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• pp.471-483
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• 2014

Since 2009 of global financial crisis, shipbuilding industry has undergone hard times seriously. After such a long depression, the latest global shipping market index shows that the economic recovery of global shipbuilding market is underway. Especially, nations with enormous resources are going to increase their productivity or expanding their shipyards to accommodate a large amount of orders expected in the near future. However, few commercial projects have been carried out for the practical shipyard layout designs even though those can be good commercial opportunities for shipbuilding engineers. Shipbuilding starts with a shipyard construction with a large scale investment initially. Shipyard design and the equipment layout problem, which is directly linked to the productivity of ship production, is an important issue in the production planning of mass production of ships. In many cases, shipbuilding yard design has relied on the experience of the internal engineer, resulting in sporadic and poorly organized processes. Consequently, economic losses and the trial and error involved in such a design process are inevitable problems. The starting point of shipyard construction is to design a shipyard layout. Four kinds of engineering parts required for the shipyard layout design and construction. Those are civil engineering, building engineering, utility engineering and production layout engineering. Among these parts, production layout engineering is most important because its result is used as a foundation of the other engineering parts, and also, determines the shipyard capacity in the shipyard lifecycle. In this paper, the background of shipbuilding industry is explained in terms of engineering works for the recognition of the macro trend. Nextly, preliminary design methods and related case study is introduced briefly by referencing the previous research. Lastly, the designed work of layout design is validated using the computer simulation technology.

• 해양환경안전학회지
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• 제14권4호
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• pp.325-331
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• 2008

최근 조선산업의 호황으로 인하여, 신생 조선소들이 많이 설립되고 있다. 이러한 조선소의 설비상의 특징은 기존의 조선소에 비해 규모가 크며, 또한 진수방식을 대형조선의 방식인 드라이도크 진수를 채택하고 있다. 본 연구 논문에서는 드라이도크 게이트의 구조 설계 및 유한요소법을 적용한 구조해석에 대해서 나타내고 있다. 설계는 트라이본을 사용하였고, 구조강도 평가는 범용 유한요소 해석 프로그램인 ANSYS Multiphysics 모듈을 이용하여 계산하였다. 드라이도크 게이트는 자주 개폐를 하지 않으며, 도크내에서 일정한 건조 기간동안 외부의 해수압을 견딜 수 있는 구조 강도를 갖고 있어야만 한다. 실제적으로, 이 구조물의 설계 및 구조강도 평가에 대한 자료는 거의 찾아볼 수가 없어서, 설계 기준 및 합리적인 구조강도 평가에 대한 기준이 필요시 되고 있다. 향후 이러한 구조물의 설계 및 구조강도 평가에 본 연구논문은 기초적인 자료 및 참고문헌으로 유익하게 사용되리라고 판단된다.