• Title/Summary/Keyword: Form parameter

Search Result 941, Processing Time 0.023 seconds

Preliminary Hull Form Design Using Form Parameter Method and Neural Networks (Form Parameter 방법과 신경망을 이용한 초기 선형 설계)

  • Park, Won;Shin, Sung-Chul;Kim, Soo-Young;Jang, Hyeon-Jae
    • Journal of Ocean Engineering and Technology
    • /
    • v.13 no.4 s.35
    • /
    • pp.174-181
    • /
    • 1999
  • A form parameter method compounds the form parameters which define the hull geometric characteristics. This method can transform a hull form by changing the form parameters. The form parameter method is a hull define method without utilization of mother ships. However it is difficult to determine these form parameters. Thus, we are complemented the form parameter method using the neural networks. It is found that the form parameter method using the neural networks is efficient in hull form design by consideration of application examples.

  • PDF

Preliminary Hull Form Generation Using Fuzzy Model (Fuzzy 모델을 이용한 초기선형 생성)

  • Soo-Young Kim;Yeon-Seung Lee
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.29 no.4
    • /
    • pp.36-44
    • /
    • 1992
  • To improve the B-spline form-parameter method being used in preliminary hull form generation, this research considers fuzzy modeling of the relationships among form-parameters based on the actual ship data analysis. Form-parameter values are determined through fuzzy inference. To verify the validity of the proposed fuzzy model the hull forms of actual ships are compared with hull forms generated by fuzzy model.

  • PDF

Hull Form Optimization Based on From Parameter Design (Form Parameter Design 을 이용한 선형최적화)

  • Lee, Yeon-Seung;Choi, Young-Bok
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.46 no.6
    • /
    • pp.562-568
    • /
    • 2009
  • Hull form generation and variation methods to be mainly discussed in this study are based on the fairness optimized B-Spline form parameter curves (FOBFC). These curves can be used both as indirect modification function for variation and as geometric entities for hull form generation. The flexibility and functionality of geometric control technique play the most important role for the success of hull form optimization. This study shows the hydrodynamic optimization process and the characteristics of optimum design hull forms of a 14,000TEU containership and 60K LPG carrier. SHIPFLOW has been used as a CFD solver and FS-Framework as a geometric modeler and optimizer.

Ship Lines Creation by B-Spline Form Parameter Method (B-Spline 형상계수 방법에 의한 선형 생성)

  • S.Y. Kim;S.W. Kang
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.29 no.2
    • /
    • pp.8-17
    • /
    • 1992
  • There has been considerable reseach on the representation of a hull form which is a 3-dimensional free surface. A form parameter method to describe the hull form by means of form parameters which represent the characteristics of the given hull form geometry has been recently paid special attention with the advent of powerful computer. However, there have been reported many problems to the conventional form parameter for the practical hull form generation. In the present paper, an attempt has been made to creak hull form by combining the form parameter method with the B-spline curve which can be best fitted to free surfaces. In an application, the present method is used to generates a Bulk carrier hull form and compared with the existing hull form to prove its applicability for the hull form generation.

  • PDF

A Study on Form Parameter Method by Optimum Vertex Point Search (조정점 최적탐색에 의한 Form Parameter 방법에 관한 연구)

  • 김수영;신성철;김덕은
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.39 no.4
    • /
    • pp.60-65
    • /
    • 2002
  • In order to generate hull form, we introduced optimization process. Fairness criteria is applied to object function, B-Spline control vertices are considered as design variables, optimization is proceeded with satisfying geometric constraint conditions. GA(Genetic Algorithm) and optimality criteria are applied to optimization process in this study.

Preliminary Hull Form Generation by Form Parameter Method using GA (GA를 이용한 Form parameter 방법에 의한 초기선형 생성)

  • Kim, Su-Young;Shin, Sung-Chul;Shin, KYoung-Yup
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.12 no.1
    • /
    • pp.44-51
    • /
    • 2002
  • In order to generate hull form, fairness criteria applies to object function, B-spline curve vertices are considered as design variables, optimization is proceeded with satisfying geometric constraint conditions. GA(Genetic Algorithm) and optimality criteria apply to optimization process in this study.

Color lens CIE L*a*b* coordination transfer by tinted time (착색시간에 따른 칼라렌즈 색좌표 이동)

  • Jeong, Byung-Mann;Park, Kwang-Ho;Kim, Yong-Geun
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.8 no.1
    • /
    • pp.53-57
    • /
    • 2003
  • R, G, Y, B color lenses Manufactured increasing tinted time by 5 min term. CIE $L^*a^*b^*$ coordination's analysis used spectrophotometer and CIE $L^*a^*b^*$ color system. CIE $L^*a^*b^*$ coordination transfer form about tinted time being $$b^*(Y-B)={\beta}a^*+{\alpha}$$ change to do linear almost. In red case, move in $G{\rightarrow}R$, $B{\rightarrow}Y$ form tinted time increases, and Parameter ${\alpha}$, ${\beta}$ value got each -3.49 and 0.90. In green case, CIE $L^*a^*b^*$ coordination transfer form is $R{\rightarrow}G$, $B{\rightarrow}Y$ form. Got the pure green color color in 10 min's tinted time. Parameter ${\alpha}$, ${\beta}$ value got each -0.72 and -0.55. Get into pure yellow and blue color case tinted time increases. Parameter ${\alpha}$, ${\beta}$ value are 14.11 and 1.58 in yellow, and Parameter ${\alpha}$, ${\beta}$ value are -11.62 and 1.30 in blue color.

  • PDF

Mathematical Description of Seedling Emergence of Rice and Echinochloa species as Influenced by Soil burial depth

  • Kim Do-Soon;Kwon Yong-Woong;Lee Byun-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.51 no.4
    • /
    • pp.362-368
    • /
    • 2006
  • A pot experiment was conducted to investigate the effects of soil burial depth on seedling emergences of rice (Oryza sativa) and Echinochloa spp. and to model such effects for mathematical prediction of seedling emergences. When the Gompertz curve was fitted at each soil depth, the parameter C decreased in a logistic form with increasing soil depth, while the parameter M increased in an exponential form and the parameter B appeared to be constant. The Gompertz curve was combined by incorporating the logistic model for the parameter C, the exponential model for the parameter M, and the constant for the parameter B. This combined model well described seedling emergence of rice and Echinochloa species as influenced by soil burial depth and predicted seedling emergence at a given time after sowing and a soil burial depth. Thus, the combined model can be used to simulate seedling emergence of crop sown in different soil depths and weeds present in various soil depths.

A Study on the Preliminary Design of Hull Form considering Viscuous Resistance (점성저항을 고려한 선형의 초기설계에 관한 연구)

  • 이경도
    • Journal of Ocean Engineering and Technology
    • /
    • v.14 no.2
    • /
    • pp.112-116
    • /
    • 2000
  • To determine a preliminary hull form with a minimum viscous resistance this study considers the systematic variations of full form and calculations of the viscous resistance for varied hull forms. A preliminary hull form can be determined from a parametric study of viscous resistance.

  • PDF

Necessary Conditions of Optimal Distributed Parameter Control Systems (분포정수계통의 최적제어 필요조건)

  • Kyung Gap Yang
    • 전기의세계
    • /
    • v.19 no.2
    • /
    • pp.21-23
    • /
    • 1970
  • Necessary conditions of optimal distributed parameter control systems, Hamiltons coanonical equations, welerstress condition, transversality condition and boundary condition are obtained, when the control function is constrained and the performance index takes on the general form. Also it is concluded that the lumped parameter system is the special case of the distributed parameter system.

  • PDF