• 제목/요약/키워드: exact

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광학탑재체 지지구조물 열지향오차 해석기법 연구

  • 김경원;김진희;이주훈;진익민
    • 항공우주기술
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    • 제4권1호
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    • pp.45-48
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    • 2005
  • 본 논문은 광학탑재체 지지구조물의 열지향오차 해석기법에 대한 연구이다. 광학탑재체 지지구조물의 열지향오차 해석을 수행하기 위해서는 위성본체 전체의 유한요소모델을 필요로 한다. 그러나 광학탑재체 지지구조물의 초기 설계시 위성본체의 유한요소모델이 정해지지 않기 때문에, 열지향오차 해석시 유한요소모델이 존재하지 않더라도 위성본체에 의한 열지향오차를 유도하는 해석기법이 필요하게 된다. 본 논문에서는 이러한 해석기법과 실제 해석시 이를 반영하는 구체적인 방법에 대해서 서술한다.

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PROJECTIONS OF PSEUDOSPHERE IN THE LORENTZ 3-SPACE

  • Birman, Graciela S.;Desideri, Graciela M.
    • 대한수학회보
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    • 제44권3호
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    • pp.483-492
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    • 2007
  • In this paper, we study the map projections from pseudo-sphere $S_1^2$ onto the non-lightlike surfaces in the 3-dimensional Lorentzian space, $L^3$, with curvature zero. We show geometrical means and properties of $\mathbb{R}{\times}S_1^1-cylindrical$, $S^1{\times}L-cylindrical$ and $\mathbb{R}{\times}H_0^1-cylindrical$ projections defined on $S_1^2$ to cylinders $\mathbb{R}{\times}S_1^1,\;S^1{\times}L$ and $\mathbb{R}{\times}H_0^1$, respectively, and orthographic and stereographic projections on $S_1^2$ to Lorentzian plane, $L^2$.

GENETIC ALGORITHMIC APPROACH TO FIND THE MAXIMUM WEIGHT INDEPENDENT SET OF A GRAPH

  • Abu Nayeem, Sk. Md.;Pal, Madhumangal
    • Journal of applied mathematics & informatics
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    • 제25권1_2호
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    • pp.217-229
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    • 2007
  • In this paper, Genetic Algorithm (GA) is used to find the Maximum Weight Independent Set (MWIS) of a graph. First, MWIS problem is formulated as a 0-1 integer programming optimization problem with linear objective function and a single quadratic constraint. Then GA is implemented with the help of this formulation. Since GA is a heuristic search method, exact solution is not reached in every run. Though the suboptimal solution obtained is very near to the exact one. Computational result comprising an average performance is also presented here.

요부(腰部) 독맥경(督脈經)의 혈위(穴位) 결정방법(決定方法)에 관한 연구(硏究)(X-선상(線像)을 중심(中心)으로) (The Research about Checking Method of Governor Vessel's Acupoints at Lumbar Regions : (compared with X-ray measuring))

  • 최익선
    • Journal of Acupuncture Research
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    • 제17권4호
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    • pp.1-4
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    • 2000
  • For checking the exact acupuncture points of Governor Vessel(GV) at lumbar regions, five kinds of method were used to 100 patients who have treated in outpatient in our hospital. They were attached distinguishable stainless steel by the methods. And those were compared with X-ray measuring. As a results, the best method to check Yoyang-gwan(GV3, Ya~oyanggua~n) was the way of using both iliac crests at lateral lying position.

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A Unified Approach to Exact, Approximate, Optimized and Decentralized Output Feedback Pole Assignment

  • Tarokh, Mahmoud
    • International Journal of Control, Automation, and Systems
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    • 제6권6호
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    • pp.939-947
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    • 2008
  • The paper proposes a new formulation of the output feedback pole assignment problem. In this formulation, a unified approach is presented for solving the pole assignment problem with various additional objectives. These objectives include optimizing a variety of performance indices, and imposing constraints on the output feedback matrix structure, e.g. decentralized structure. Conditions for the existence of the output feedback are discussed. However, the thrust of the paper is on the development of a convergent pole assignment algorithm. It is shown that when exact pole assignment is not possible, the method can be used to place the poles close to the desired locations. Examples are provided to illustrate the method.

Inference on Overlapping Coefficients in Two Exponential Populations Using Ranked Set Sampling

  • Samawi, Hani M.;Al-Saleh, Mohammad F.
    • Communications for Statistical Applications and Methods
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    • 제15권2호
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    • pp.147-159
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    • 2008
  • We consider using ranked set sampling methods to draw inference about the three well-known measures of overlap, namely Matusita's measure $\rho$, Morisita's measure $\lambda$ and Weitzman's measure $\Delta$. Two exponential populations with different means are considered. Due to the difficulties of calculating the precision or the bias of the resulting estimators of overlap measures, because there are no closed-form exact formulas for their variances and their exact sampling distributions, Monte Carlo evaluations are used. Confidence intervals for those measures are also constructed via the bootstrap method and Taylor series approximation.

직경이 작은 유압관로에서의 동특성 (Dynamic Respeonse of Hydraulic Pipe Lines with a Relative Small Diameter)

  • 유영태
    • 한국생산제조학회지
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    • 제8권4호
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    • pp.38-44
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    • 1999
  • This paper primarily directed toward analyzing the frequency response in hydraulic pipe lines with a small diameter. The exact solution to the frequency response is obtained by using the complicated transfer function. The discrepancy with the exact and the approximate is small so the approximation solution is adopted to compare the experimental results with the theoretical analysis. In this experiment the input frequency was generated by the frequency generator with the ball valve and speed controller. In order to compare the theoretical were forms with the experimental ones the trace obtained from the oscilloscope is photographed, The diameter the length of lines and input pressure amplitude are varied to investigate their effects,. the experiment results show that th values of dimensionless parameter are very affected to the phase delay and guide response time in the design of pressure manifold to measure the pressure of hydraulic pipelines.

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댐의 시간영역 지진응답 해석을 위한 호소의 집중변수모델 (Lumped Parameter Model of Transmitting Boundary for the Time Domain Analysis of Dam-Reservoir Systems)

  • 김재관
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2000년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2000
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    • pp.143-150
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    • 2000
  • A physical lumped parameter model is proposed for the time domain analysis of dam-reservoir system. The exact solution of transmitting boundary is derived for a semi-infinite 2-D reservoir of constant depth. The characteristics of the solution are examined in both frequency and the domains. Mass and damping coefficient are obtained from asymptotic behavior of the frequency domain solution. Further refinement to the lumped model is made by approximating the kernel function of the convolution integral in the exact solution. Finally a new physical lumped parameter model is proposed that consists of two masses, a spring and two dampers for each mode. It is demonstrated that new lumped parameter model of transmitting boundary can give excellent results.

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