• 대한조선학회논문집
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• 제44권5호
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• pp.534-541
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• 2007

This paper suggests the mathematical method for the estimation of the required engine output for WIG crafts. The engine size of a WIG craft Is a key parameter in the design stage, because WIGs should overcome the hump drag during the take-off. Therefore, it is very important for a WIG designer to estimate required power and state change during take-off. The mathematical method was developed based on the steady planing state model of a planing boat. Through numerical calculations on various take-off states, it was found that the suggested method could give reasonable estimation of required power and state change during take-off.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.585-598
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• 2021

The course-keeping stability of a high speed planing boat should be considered at the design stage for its safe operations. The shape of waterjet intake plane is one of important design parameters of a waterjet propelled planing boat. That has significant influences on the stern flow patterns and pressure distributions. In this study, the effects of the waterjet intake shapes of planing boats on the course-keeping stabilities are investigated. Two kinds of designed planing boats have the same dimensions, but there are differences in waterjet intake plane shapes. Captive and free-running model tests, Computational Fluid Dynamics (CFD) analyses are carried out in order to estimate their hydrodynamic performances including course-keeping stabilities. The results show that the flat and wide waterjet intake plane of the initially designed boat makes the course-keeping stability worse. The waterjet intake shape is redesigned to improve the course-keeping stability. The improved performances are confirmed by free-running model tests and full-scale trials.

• 수산해양기술연구
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• 제34권3호
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• pp.283-286
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• 1998

활주선 선형을 갖는 고속어선의 저항특성을 체계적으로 연구하기 위한 제 1단계로서 단면형상 및 장-폭비와 저항특성과의 관계에 대한 실험적 연구를 수행하였다. 본 연구는 새로운 고속 활주형 어선을 개발하기 위한 초기연구로서 다음의 내용을 포함하고 있다. - 4가지 단면형상에 대한 저항 특성 - 4가지 장-폭비에 대한 저항 특성

• 대한조선학회논문집
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• 제51권5호
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• pp.369-379
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• 2014

Planing hull forms have significant influences on those hydrodynamic performances in calm water and in waves. Therefore, the hydrodynamic performance of a planing vessel should be predicted by model tests or theoretical calculations, and be confirmed whether it shows the performance requirements at the design stage. In this study, four planing hull forms are designed with the goal of the improvement of resistance and seakeeping performance, and 1/6.5 scale model tests are carried out in Seoul National University towing tank. The effects of design parameters such as length-to-beam ratio, deadrise angle and forebody shape on the hydrodynamic performance are investigated, based on model test results. Running attitude and resistance of model ships in calm water are also estimated by empirical formulae proposed by Savitsky (1964; 2007; 2012), and compared with the model test results. It is shown that calm water performance of non-prismatic planing hulls can be predicted well by Savitsky (2012)'s formula which improves the original Savitsky(1964/2007)'s formula by taking into account the variations of deadrise angles, and the actual angles between the hull bottom and the free surface.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 추계종합학술대회
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• pp.274-277
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• 1999

대형 선박에는 각종 저장용 탱크가 산재해 있으며, 이들 각 탱크의 잔존량 및 이상 유무를 실시간으로 취합하여, 모니터링 할 수 있는 시스템은 선박에 있어서 필수적이다. 기존의 선박용 탱크 모니터링 시스템에서 입력되는 데이터의 종류가 많은 경우, 이를 구분하기 위한 처리와 전송 과정에서 발생되는 전송 에러에 대한 처리를 호스트 컴퓨터에서 수행하므로 많은 부하가 걸리게 된다. 따라서 된 논문에서는 에러 자동 검출 및 정정의 자동 수행 및 실시간 분산 제어 기능을 제공하는 CAN을 이용해 실시간 탱크 모니터링 시스템을 설계하고, 구현한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1758-1761
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• 1997

The problem of long range capacity expansion planing for chemical processing network under uncertain demand forecast secnarios is addressed. This optimization problem involves capactiy expansion timing and sizing of each chemical processing unit to maximize the expected net present value considering the deviation of net present values and the excess capacity over a given time horizon. A multiperiod mixed integer nonlinear programming optimization model that is both solution and modle robust for any realization of demand scenarios is developed using the two-stage stochastic programming algorithm. Two example problems are considered to illustrate the effectiveness of the model.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1980-1983
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• 2005

The characteristic of sheet metal process is the few loss of material during process, the short processing time and the excellent price and strength. The sheet metal process with above characteristic is common used in industrial field, but in order to analysis irregular field problems the reliable and economical analysis method is demanded. Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behaviour. Among Finite element method, The static-implicit finite element method is applied effectively to analyze real-size auto-body panel stamping processes, which include the forming stage. In this paper, it was focussed on the drawability factors on auto-body panel stamping by AUTOFORM with using tool planing alloy to reduce law price as well as high precision from Design Optimization of ide. According to this study, the results of simulation will give engineers good information to access the Design Optimization of die.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 제5회 박판성형 SYMPOSIUM
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• pp.81-85
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• 2006

The characteristic of sheet metal process is the few loss of material during process, the short processing time and the excellent price and strength. The sheet metal process with above characteristic is common used in industrial field, but in order to analysis irregular field problems the reliable and economical analysis method is demanded. Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behaviour. Among Finite element method, The static-implicit finite element method is applied effectively to analyze real-size auto-body panel stamping processes, which include the forming stage. In this paper, it was focussed on the drawability factors on auto-body panel stamping by AUTOFORM with using tool planing alloy to reduce law price as well as high precision from Design Optimization of die. According to this study, the results of simulation will give engineers good information to access the Design Optimization of die.

• 산업공학
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• 제12권4호
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• pp.514-531
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• 1999

This paper deals with the design of the manufacturing information system which is able to respond rapidly to various requirements of customers in make-to-order environment. The system is required to maintain a consistent flow of information from the start to the end. For this, we adopt an approach based on Information Engineering (IE) methodology, which consists of four stages: planning, analysis, basic design, and detail design. The first is a planing stage which establishes a project goal and organizes a project team. In the second stage, current activities are analyzed and problems are defined. The basic design is accomplished in the third stage, where a project scope is defined and an overall feature of the new system is presented. And then, in the last stage, the operation plan of each subsystem is drawn up in detail and all subsystems are integrated. This study applies the methodology to the case of H company and focuses on designing forms which are easy-to-write, easy-to-understand, and field-oriented. These forms are interrelated and can be used for systematic analysis and design. By applying them to the system design, we have obtained effect of reducing cost and time.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.120-125
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• 2003

기획단계에서의 예상 공사비 추정은 사업성 자체를 판단하는 중요한 자료로써 활용된다. 그러므로 사업주는 보다 정확한 금액자료의 산출을 기대하는데 이를 위해서 세계적으로 Cost 전문가들의 많은 연구검토가 있어 왔으나 아직 국내의 적산사는 주로 물량산출 및 상세 견적업무에만 매달려 있는 실정이다. 본 논문은 요소별/기능 부위별 비용의 분석을 통한 Database를 활용하여 개산견적의 결과물을 보다 정확하게 만든 사례의 소개를 통해 국내 개산견적 실무에 일조하고자 한다.