• Journal of the Society of Naval Architects of Korea
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• v.32 no.3
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• pp.29-36
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• 1995

This paper presents a variation method of the parent ship using sectional area curve & the definition of NURBS curve. That is, global variation of the hull form is made systematically by the geometrical property of sectional area curve, and Local variation of the hull form is executed by the definition of NURBS curve. Then the designer may determine New hull form considering New section area curve, design condition, etc.

• Journal of Ocean Engineering and Technology
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• v.12 no.3 s.29
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• pp.96-102
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• 1998

This paper presents to create a SAC(Sectional Area Curve) using an ANFIS(Adaptive-Network-based Fuzzy Inference System). First, it defines SACs of parent ships by using a B-spline approximation and a genetic algorithm and accumulates a database about SAC's control points. Second, it learns an ANFIS from parent ship data, which are related with principal dimensions and SAC's control points. This process is to model an ANFIS for SAC inferreice. When an ANFIS modeling is completed, we can determine a SAC through an ANFIS inferring.

• Bulletin of the Society of Naval Architects of Korea
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• v.25 no.4
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• pp.28-38
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• 1988

This paper describes the statistical analysis method of predicting the ship resistance. The equation for the wavemaking resistance coefficient is derived as the principal dimensions and sectional area coefficients by using the wavemaking resistance theory and its regression coefficients are determined from the regression analysis of the resistance test results. The equation for the form factor is derived by purely regression analysis of the principal dimensions, sectional area coefficients and resistance test results. Also, it is shown that the wavemaking resistance can be minimize by varying the sectional area curve without changing the principal dimensions of the ship. This methods were applied to the resistance prediction of a bulk carrier. And the, the modified hull form with minimum wavemaking resistance was obtained and the reduction of effective power was confirmed by the resistance test.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.2
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• pp.1-9
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• 1995

This paper suggests a numerical method that creates and varies hull form geometry of underwater vehicle. That is, it induces the cylindrical underwater vehicle from principal dimensions-total length, the length of parallel middle body, the coefficient defining entrance & run parts etc.-and represents using NURBS curve. Also, each section of hull form is varied by user interface and Sectional Area Curve is generated.

• Bulletin of the Society of Naval Architects of Korea
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• v.26 no.2
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• pp.1-12
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• 1989

This paper presents a method of minimizing the wave resistance components, due to the linear wave propagating to the far field and the breaking wave in the vicinity of the hull. This method consists of the linear optimization method for the linear wave resistance and the statistical optimization method for the breaking wave resistance through the analysis of the experimental data. For the purpose of the application, a wall-sided model with parabolic waterplane shape was selected as a basic hull form, and two modified hull forms with varied $C_p-curve$ of the fore-body were derived from the linear wave optimization method and the empirical method. The correlation between the linear wave resistance and the breaking wave resistance according to the $C_p-curve$ variation of the fore-body was investigated through the experimental and analytical results for the three hull forms. The fore-body shape optimized by the present method shows the reduction of the wave resistance by 47% comparing to the basic hull form at the design speed($F_n=0.26$).

• Journal of the Korean Institute of Intelligent Systems
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• v.8 no.5
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• pp.45-50
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• 1998

This paper presents the process generating the 3-dimensional free f o r m hull form by using an ASMOD(Adaptive Spline Modeling of Observation Data) and a hybrid curve approximation. For example, we apply an ASMOD to the generation of a SAC(Sectiona1 Area Curve) in an initial hull form design. That is, we define SACS of real ships as B-spline curves by a hybrid curve approximation (which is the combination method of a B-spline fitting method and a genetic algorithm) and accumulate a database of control points. Then we let ASMOD learn from the correlation of principal dimensions with control points and make the ASMOD model for SAC generation. Identically, we apply an ASMOD to the generation of other hull form characteristic curves - design waterline curve, bottom tangent line, center profile line. Conclus~onally we can generate a design hull form from these hull form characteristic curves.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.357-357
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• 2023

2017년 7월 16일 집중호우로 인해 무심천 상류에 위치한 충청북도 청주시 상당구 남일면 고은리 655번지의 농경지 침수 피해가 발생하였다. 대상지역의 우안 제방에는 기존에 수동식 수문이 설치되어 있었으나 내구연한이 지나고 부식되어 수년전에 망실되었으며, 2017년 7월 홍수 이후 유사한 규모의 홍수가 발생 할 경우 대상지역은 홍수피해를 겪을 수밖에 없는 상황에 처해 있다. 이에 따라 홍수방어 시설인 전동식 수문을 설치하여 설치 전·후의 침수 피해를 분석하였다. 본 연구에서는 청주 수위관측소의 2017년 7월 15~16일 수위자료를 수집하여 수위-유량관계곡선식(Rating Curve)을 적용한 시간당 유량자료를 산정하였으며, 수문설치 지점인 고은리 655번지를 시점으로 하류 약 15.871km에 위치한 흥덕교까지 HEC-RAS 모형을 이용하여 홍수분석을 수행하였다. 무심천 우안 제방 내 수문이 설치되기 전과 후에 따른 대상지역의 제내지 침수구역 범위를 산정하여 비교 분석하였다. 측점은 96개의 횡단면으로 구성하였으며, 부정류 해석을 위한 경계조건으로 상류단 유입량, 측방 유입량 및 하류단 수위를 적용하였다. 홍수분석 결과 단면별 최대수위는 EL.41.92m~EL.66.29m의 범위를 나타내고 있으며, 적용 홍수에 따른 최대 유속은 3.17 m/s로나타났다. 수문설치 지점의 하천 횡단에서 발생하는 최고 수위는 EL.66.29m로 산정되었으며, EL.66.29m를 기준으로 전동식 수문이 설치되기 전과 후의 침수범위를 분석하였다. 설치 전 홍수분석 결과 제내지 침수구역의 면적은 141,309.3m²로 분석되었다. 전동식 수문을 설치함에 따라 대상지역의 제내지 침수 피해를 겪지 않은 것으로 분석되었다. 향후 전동식 수문과 IoT기술을 접목하여 지자체의 재난관리 시스템과 연동할 수 있다면, 유사한 침수피해를 최소화 하는데 기여할 것으로 판단된다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.2
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• pp.89-100
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• 1993

This paper is a study on the earth volume calculation using CAD and LISP(LIST Processing) in the route alignment. The utility enlargement in the industry field and the considerable progress of computer make the automatic design and manufacture for the development of CAD/CAM/CAE technique possible, and the automatic design of civil engineering works is continuously progressive. In this study we are intend to improve an effect of civil engineering work by the automatic earth volume calculation in route alignment. This paper aims to construct the automatic design system of civil engineering work and the procedures; (1) The programming of the self-scanning program of the land information introducing Digital Terrain Model concept in the map (2) Systematic algorithm construction using LISP and grafting CAD system (3) Automatic design and calculation of the mass curve and earth volume.

• Journal of Ocean Engineering and Technology
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• v.27 no.2
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• pp.1-7
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• 2013

This paper aims at contributing to the field of ship design by introducing new systematic variation methods for ship hull forms. Hull form design is generally carried out in two stages. The first is the global variation considering the sectional area curve. Because the geometric properties of a sectional area curve have a decisive effect on the global hydrodynamic properties of ships, the design of a sectional area curve that satisfies various global design conditions, e.g., the displacement, longitudinal center of buoyancy, etc., is important in the initial hull form design stage. The second stage involves the local design of section forms. Section forms affect the local hydrodynamic properties, e.g., the local pressure in the fore- and aftbody. This paper deals with a new method for the systematic variation of sectional area curves. The longitudinal volume distribution of a ship depends on the sectional area curve, which can geometrically be controlled using parametric variation and a variation that uses the modification function. Based on these methods, we suggest a more generalized method in connection with the derivation of the lines for a new design compared to those for similar ships. This is the so-called the volumetric balanced variation (VOB) method for ship forms using a B-spline modification function and an optimization technique. In this paper the global geometric properties of hull forms are totally controlled by the form parameters. We describe the new method and some application examples in detail.

• Journal of Ocean Engineering and Technology
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• v.30 no.4
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• pp.235-242
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• 2016

In general, ship hull form design is carried out in two stages. In the first stage, the longitudinal variation of the sectional area curves is adapted from a similar mother ship to determine the volume distribution in ships. At this design stage, the initial design conditions of displacement, longitudinal center of buoyancy, etc. are satisfied and the global hydrodynamic properties of the structure are optimized. The second stage includes the local designing of the sectional forms. Sectional forms are related to the local pressure resistance in the fore- and aft-body shapes, cargo boundaries, interaction between the hull and propeller, etc. These relationships indicate that the hull sections need to be optimized in order to minimize the local resistance. The volumetric balanced (VOB) variation of ship hull forms has been suggested by Kim (2013) as a generalized, systematic variation method for determining the sectional area curves in hull form design. This method is characterized by form parameters and is based on an optimization technique. This paper emphasizes on an extensional function of the VOB considering a geometrical wave profile. We select a container ship and an LNG carrier to demonstrate the applicability of the proposed technique. Through analysis, we confirm that the VOB method, considering the geometrical wave profile, can be used as an efficient tool in the hull form design for ships.