• 한국기계가공학회지
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• 제18권1호
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• pp.116-121
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• 2019

The LVDT (Linear Variable Displacement Transducer) type sensor used for the existing ship's steering gear is simple on / off that does not perform proportional control operation to the control & unloading device. When the main spool is located at both extremes, It is reflected in the price by using an expensive sensor for import. In this paper, the Hall Effect Sensor is applied to Hydraulic Locking Alarm to analyze classification rules, structure, characteristics and operation principle of valves, and research on localization development in terms of cost reduction. The comparative analysis of the existing prototypes and the cause analysis of the problems were carried out, and the structural analysis showed satisfactory results within the allowable stress range. In addition, it was verified through experiments that the actual operation is realized by applying the actual developed product, and it was confirmed that the load on the maximum value exceeds the allowable maximum load even in the case of the universal tensile test in preparation for the departure of the rod casing.

• 대한조선학회논문집
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• 제31권3호
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• pp.38-46
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• 1994

통합 생산 시스템의 역할은 제품의 전 생명주기에 걸쳐 필요한 다수의 응용 프로그램을 통합하는 것이다. STEP은 독립적으로 개발된 응용 프로그램의 통합을 쉽게 하기 위하여 정보모델과 인터페이스를 정의하는 국제 표준화 작업이다. STEP을 이용한 조선 통합생산시스템(CIMS)에서 정보모델은 EXPRESS로 정의되어 있으며, 이 정보모델은 데이타베이스의 스키마로 번역되어 진다. 논문에서는 조선공정계획 시스템에 포함된 두개의 응용 프로그램(즉, 블럭분할 시스템과 탑재 시스템)을 이용하여 개발된 프로토타입의 운용을 설명한다. 예로서 본 논문에서는 관계형 데이타베이스(Oracle)에 저장되어 있는 실제의 데이타를 보여준다.

• 대한조선학회논문집
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• 제38권2호
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• pp.71-78
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• 2001

조선분야에서 CNC, 혹은 CAM이 사용되는 분야는 주로 강재 절단, 프로펠러 제작 자동화와 수조 실험용 모델제작에 관한 것이며 대학에서는 대부분 선형과 구조 설계용 CAD 연구를 수행하고 있고 CAM 분야는 활성화되어 있지 않은 편이다. 본 문에서는 Pro/Engineer CAD 시스템으로 3차원 선체 형상을 모델링 하고 이를 CNC 공작기계로 제작하는 과정을 수행하고 부수적으로 이기종 소프트웨어간 데이터 교환을 위한 중립 데이터 양식에 관한 기초 조사연구도 하였다. CIM 과정에서 소프트웨어간의 형상 정보 교환 시 IGES, STEP을 사용할 수 있으나 본 연구에 적용된 CAM s/w에서 STEP을 인식할 수 없어 IGES를 사용하였고 TRIMC VMC 공작기계의 제작물 크기에 제한이 있어 작은 규모의 선박 모형(prototype) 가공을 수행하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.272-276
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• 2003

In this paper, current application of VR in naval architecture and ocean eng. Design is surveyed and VR process is implemented in ship navigation system. So far, very sophisticated VR applications have announced but not published yet. The reason not published may be that the application is for the navy ship of which the information could not be opened to the public. Also there is another area implementing Simulation Based Design, i..e., visualization of the integration process from initial design to the manufacturing. Herein, the tendency of VR in this area is surveyed, so the international application of VR is introduced. Trough the analysis the most appropriate applicability of VR in this area can be distinguished. And to show the application, ship navigation VR is programmed using OpenGL graphics software.

• 산업공학
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• 제15권3호
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• pp.230-240
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• 2002

Information technologies centered on the internet in the area of shipbuilding and marine engineering further incur the needs to increase the flexibility of the organization, the dispersion of work process, and the use of out sourcing, as well as the globalization of related market. In near future, electronic commerce and concurrent engineering based on CALS/EC and the Internet will be an integral part of the environment and upon these changes, ship design and construction will become a computer supported cooperative work of many dispersed and specialized groups. As the means of active response to these environmental changes, many new concepts such as digital shipbuilding, virtual shipyard, and simulation based design are appearing. In this paper, the concept and current status of digital manufacturing in general manufacturing industry will be reviewed. Then, related technologies, area of application and methods of digital manufacturing in shipbuilding and marine industries are presented. In addition, virtual assembly simulation system for shipbuilding(VASSS), a tool for crane operability and block erection simulation in virtual dock based on 3D product model, will be introduced.

• Journal of Mechanical Science and Technology
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• 제18권11호
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• pp.1923-1931
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• 2004

Manufacturing of complex surface plates in stern and stem is a major factor in cost of a preliminary ship design by computing process. If these hull plate parts are effectively classified, it helps to compute the processing cost and find the way to cut-down the processing cost. This paper presents a new method to classify surface plates effectively in the preliminary ship design using neural network. A neural-network-based ship hull plate classification program was developed and tested for the automatic classification of ship design. The input variables are regarded as Gaussian curvature distributions on the plate. Various applicable rules of network topology are applied in the ship design. In automation of hull plate classification, two different numbers of input variables are used. By observing the results of the proposed method, the effectiveness of the proposed method is discussed. As a result, high prediction rate was achieved in the ship design. Accordingly, to the initial design stage, the ship hull plate classification program can be used to predict the ship production cost. And the proposed method will contribute to reduce the production cost of ship.

• 대한조선학회논문집
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• 제45권5호
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• pp.547-553
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• 2008

Multi Progress Planning System problem in a multi-stage manufacturing system have a complexity and peculiarity different from other kinds of production system. World leading company has invested much cost and effort into a Real-Time Planning System and intelligent manufacturing field to obtain their own competitiveness. Especially Real-Time Planning System for ship production process as a part of intelligence for a shipyard. Real-Time Planning System, simulation based system, or virtual manufacturing system is an approach to achieve a such goal. It is expected that the Real-Time Planning System will contribute to the improvement of the productivity in working process at a shipyard. Also, This Real-Time Planning System will optimize the entire shipbuilding process in a multi progress planning environment for the delivery.

• 경영과학
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• 제29권2호
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• pp.143-155
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• 2012

The purpose of this study is to formulate and solve the scheduling problem to heat-treatment process in forging process and apply it to industries. Heat-treatment is a common process in manufacturing heavy forged products in ship engines and wind power generators. Total complete time of the schedule depends on how to group parts and assign them into heat furnace. Efficient operation of heat-treatment process increases the productivity of whole production system while scheduling the parts into heat-treatment furnace is a combinatorial problem which is known as an NP-hard problem. So the scheduling, on manufacturing site, relies on engineers' experience. To improve heat-treatment process schedule, this study formulated it into an MIP mathematical model which minimizes total complete time. Three methods were applied to example problems and the results were compared to each other. In case of small problems, optimal solutions were easily found. In case of big problems, feasible solutions were found and that feasible solutions were very close to lower bound of the solutions. ILOG OPL Studio 5.5 was used in this study.

• Journal of Ship and Ocean Technology
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• 제8권4호
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• pp.45-55
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• 2004

How to achieve engineering collaboration among diverse engineering activities is one of the key topics in manufacturing fields nowadays. The infrastructure for collaborative engineering is essential, and it can be realized by information technologies and intelligent engineering applications in digital environments. Digital Manufacturing is a technology to facilitate effective product developments and agile productions by computer models representing the physical and logical schema and the behavior of real manufacturing systems including products, processes and factories. A digital factory as a well-designed and integrated digital environment is incorporated in it. In this paper, digital manufacturing is recommended as a good strategy for collaborative engineering, especially in product developments and productions. By business process analysis and some case studies, we suggested sophisticated digital models are very useful to concurrent and collaborative engineering. It is expected that digital manufacturing is a very good strategy for achieving dramatic time and cost savings in many engineering activities of many manufacturing industries, including machinery, automotive and shipbuilding.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.719-723
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• 1997

The welding automation in ship manufacturing process,especially in the sub-assembly line is considered to be a difficult job because the welding part is too huge, various, unstructured for a welding robot to weld fully automatically. The weld orocess at the sub-assembly line for ship manufacturing is to joint the various stiffener on the base panel. In order to realize automatic robot weld in sub-assembly line, robot have to equip with the sensing system to recognize the position of the parts. In this research,we developed a vision system to detect the position of base panle for sub-assembly line is shipbuilding process. The vision system is composed of one CCD camera attached on the base of robot, 2-500W halogen lamps for active illumination. In the image processing algorithm,the base panel is represented by two set of lines located at its two corner through hough transform. However, the various noise line caused by highlight,scratches and stiffener,roller in conveyor, and so on is contained in the captured image, this nosie can be eliminated by region segmentation and threshold in hough transform domain. The matching process to recognize the position of weld panel is executed by finding patterns in the Hough transformed domain. The sets of experiments performed in the sub-assembly line show the effectiveness of the proposed algorithm.