• 제목/요약/키워드: Parameterization

검색결과 326건 처리시간 0.024초

공작기계상에서의 측정데이터를 이용한 자유곡면 생성 (Generation of freeform Surface using Measured Data on the Machine Tool)

  • 이세복
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1998년도 추계학술대회 논문집
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    • pp.13-18
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    • 1998
  • The assessment of machined surface is difficult because the freeform surface must be evaluated by surface fairness as well as dimensional accuracy. In this paper, the methodology of freeform surface generation using measured data on the machine tool is presented. The reliability of measured points data is obtained by measuring error compensation. The compensated data are formulated through Non-uniform G-spline surface modeling. In order to improve the surface fairness, the generated model si smoothened by parameterization The validity and usefulness of the proposed method are examined through computer simulation and experiments on the machine tool.

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Constructing Nonlinear Sliding Surface for Spacecraft Attitude Control Problems

  • Cheon, Yee-Jin
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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    • pp.41-44
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    • 1999
  • Nonlinear sliding surface design in variable structure systems for spacecraft attitude control problems is studied. A robustness analysis is performed for regular form of system, and calculation of actuator bandwidth is presented by reviewing sliding surface dynamics. To achieve non-singular attitude description and minimal parameterization, spacecraft attitude control problems are considered based on modified Rodrigues parameters(MRP). It is shown that the derived controller ensures the sliding motion in pre-determined region irrespective of unmodeled effects and disturbances.

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An interpolation method of b-spline surface for hull form design

  • Jung, Hyung-Bae
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제2권4호
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    • pp.195-199
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    • 2010
  • This paper addresses the problem of B-spline surface interpolation of scattered points for a hull form design, which are not arbitrarily scattered, but can be arranged in a series of contours permitting variable number of points in the contours. A new approach that allows different parameter value for each point on the same contour has been adopted. The usefulness and quality of the interpolation has been demonstrated with some experimental results.

유한요소법을 이용한 애자의 전계해석 및 최적형상 설계 (Analysis and Optimum Design of Ceramic Insulator Using FEM)

  • 이향범;박일한;한송엽
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 A
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    • pp.181-183
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    • 1997
  • In this paper the analysis and optimum design of ceramic insulator is studied. The finite element method (FEM) is used for the electromagnetic solution and the design sensitivity analysis is used for the optimization. The parameterization of design variables and movable points is introduced and the linear function is used as a interpolation function.

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가변 사구간을 갖는 적응 퍼지 제어기 (Adaptive Fuzzy Controller with Variable Deadzone)

  • 구근모
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 춘계학술대회 학술발표 논문집
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    • pp.39-42
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    • 1998
  • This paper proposes an adaptive fuzzy control scheme for a class of continuous-time nonlinear dynamic systems for which an explicit linear parameterization of the uncertainty is either unknown or impossible. In order to improve robustness under approximation errors and disturbances the proposed scheme includes deadzone in adaptation laws which varies its size adaptively. The assumption of known bounds on the approximation errors and disturbances is not required since those are estimated using adaptation laws. The overall adaptive scheme is proven to guarantee uniform ultimate boundedness in the Lyapunov sense.

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Accuracy of linear approximation for fitted values in nonlinear regression

  • Kahng, Myung-Wook
    • Journal of the Korean Data and Information Science Society
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    • 제24권1호
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    • pp.179-187
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    • 2013
  • Bates and Watts (1981) have discussed the problems of reparameterizing nonlinear models in obtaining accurate linear approximation confidence regions for the parameters. A similar problem exists with computing confidence curves for fitted values or predictions. The statistical behavior of fitted values does not depend on the parameterization. Thus, as long as the intrinsic curvature is small, standard Wald intervals for fitted values are likely to be sufficient. Accuracy of linear approximation for fitted values is investigated using confidence curves.

Energy-level alignment and charge injection at electrodeorganic interfaces

  • Helander, M.G.;Wang, Z.B.;Lu, Z.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.112-114
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    • 2009
  • Charge injection at electrode-organic interfaces is key to the performance, lifetime and stability of organic electronic devices. The link between fundamental material properties and the energy-level alignment at electrode-organic interfaces will be discussed. In addition the impact of the injection barrier height-a parameterization of the energylevel alignment-on device characteristics will also be discussed.

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혼합형 유전해법을 이용한 비대칭 외판원문제의 발견적해법 (A Heuristic Algorithm for Asymmetric Traveling Salesman Problem using Hybrid Genetic Algorithm)

  • 김진규;윤덕균
    • 산업경영시스템학회지
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    • 제18권33호
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    • pp.111-118
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    • 1995
  • This paper suggests a hybrid genetic algorithm for asymmetric traveling salesman problem(TSP). The TSP was proved to be NP-complete, so it is difficult to find optimal solution in reasonable time. Therefore it is important to develope an algorithm satisfying robustness. The algorithm applies dynamic programming to find initial solution. The genetic operator is uniform order crossover and scramble sublist mutation. And experiment of parameterization has been performed.

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POSITION VECTOR OF A DEVELOPABLE q-SLANT RULED SURFACE

  • Kaya, Onur;Onder, Mehmet
    • Korean Journal of Mathematics
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    • 제26권4호
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    • pp.545-559
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    • 2018
  • In this paper, we study the position vector of a developable q-slant ruled surface in the Euclidean 3-space $E^3$ in means of the Frenet frame of a q-slant ruled surface. First, we determinate the natural representations for the striction curve and ruling of a q-slant ruled surface. Then we obtain general parameterization of a developable q-slant ruled surface with respect to the conical curvature of the surface. Finally, we introduce some examples for the obtained result.

대기오염에 의한 대기투과도 감쇠에 대한 연구 (Attenuation of the Atmospheric Aerosol Transmissivity due to Air Pollution)

  • Kim, Yoo-Keun;Lee, Hwa-Woon;Lee, Yong-Seob
    • Journal of Korean Society for Atmospheric Environment
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    • 제11권E호
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    • pp.23-29
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    • 1995
  • 산업 도시 부산에서 관측된 기상자료와 대기오염 자료를 이용해 대기오염과 대기투과도의 상호 관계를 연구하였다. 부산에서 대기오염에 의한 대기투과도를 예측하는데 경험적인 모델을 구축하기 위해 여러 기상 요소와 대기오염을 사용하였고, 이 결과를 Yamamoto et al.(1968)에 의한 대기투과도 계산 방법과 비교하였다. 그 결과, 두 방법에 의한 결과는 좋은 상관을 나타내었다. 따라서 본 연구에 의해 제시된 대기오염의 모수화는 부산에서 대기투과도와 직달일사량을 신뢰성 있게 예측하는 하나의 방법이라 생각된다. Relationship between atmospheric aerosol transmissivity and air pollution was analyzed using observed data in a large industrial city, Pusan, Korea. The atmospheric aerosol transmissivity predicted by method of present study in Pusan was assessed by the method of Yamamoto et al.(1968) in order to set up an empirical model to predict the transmissivity using the various meteorological parameters and air pollution. As a result, good correlation between these tow method re observed. Thus, it is possible to conclude that the parameterization of air pollution suggested by this study is another method to give reliable estimate of atmospheric aerosol transmissivity and direct solar irradiance in Pusan.

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