• Title/Summary/Keyword: Numerical Expression

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The Crowd Activity Analysis based on Perspective Effect in Network Camera (네트워크 카메라 영상에서 원근감 효과를 고려한 군집 움직임 분석)

  • Lee, Sang-Geol;Park, Hyun-Jun;Cha, Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.415-418
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    • 2008
  • This paper presents a method for moving objects detection, analysis and expression how much move as numerical value from the image which is captured by a network camera. To perform this method, we process few kinds of pre-processing to remove noise that are getting background image, difference image, binarization and so on. And to consider perspective effect, we propose modified ART2 algorithm. Finally, we express the result of ATR2 clustering as numerical value. This method is robust to size of object which is changed by perspective effect.

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Elastodynamic analysis by a frequency-domain FEM-BEM iterative coupling procedure

  • Soares, Delfim Jr.;Goncalves, Kleber A.;de Faria Telles, Jose Claudio
    • Coupled systems mechanics
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    • v.4 no.3
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    • pp.263-277
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    • 2015
  • This paper presents a coupled FEM-BEM strategy for the numerical analysis of elastodynamic problems where infinite-domain models and complex heterogeneous media are involved, rendering a configuration in which neither the Finite Element Method (FEM) nor the Boundary Element Method (BEM) is most appropriate for the numerical analysis. In this case, the coupling of these methodologies is recommended, allowing exploring their respective advantages. Here, frequency domain analyses are focused and an iterative FEM-BEM coupling technique is considered. In this iterative coupling, each sub-domain of the model is solved separately, and the variables at the common interfaces are iteratively updated, until convergence is achieved. A relaxation parameter is introduced into the coupling algorithm and an expression for its optimal value is deduced. The iterative FEM-BEM coupling technique allows independent discretizations to be efficiently employed for both finite and boundary element methods, without any requirement of matching nodes at the common interfaces. In addition, it leads to smaller and better-conditioned systems of equations (different solvers, suitable for each sub-domain, may be employed), which do not need to be treated (inverted, triangularized etc.) at each iterative step, providing an accurate and efficient methodology.

Allocation of the Optimal Reliability and Maintainability in Manufacturing Systems (제조 시스템의 최적 신뢰도 및 보전도 할당)

  • 이상철
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.50
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    • pp.23-32
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    • 1999
  • Reliability and maintainability allocation in the analysis of the system's design, with the objective of planning and installing the individual components in such a way that the system performance is achieved. This paper has been made to solve an important task in reliability management of manufacturing systems within the general objective being to increase productivity while maintaining costs low. Thus, the purpose of this paper is to provide an analytical approach to determine an optimal reliability and maintainability allocation, trading off among system performance and parts investment costs. Two important considerations will be addressed in this regard : (ⅰ) determine the reliability and maintainability allocation of parts which maximizes a given production index, having fixed the total cost of investments ; and (ⅱ) determine the reliability and maintainability allocation which minimizes the total cost of investments, having fixed a minimum acceptable level of productivity. The procedure proposed in this paper is able to provide to managers and designers useful indications on the reliability and maintainability characteristics of parts in series -parallel systems. And this heuristic model is a decision support tool for contractors who are involved in large scale design projects such as ship and aircraft design. Numerical examples prove that an approximate expression of the average throughput rate is sufficiently accurate to be used in a numerical optimization method.

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Flow and Heat Transfer Analysis of Copper-water Nanofluid with Temperature Dependent Viscosity Past a Riga Plate

  • Ahmad, A.;Ahmed, S.;Abbasi, F.M.
    • Journal of Magnetics
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    • v.22 no.2
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    • pp.181-187
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    • 2017
  • Flow of electrically conducting nanofluids is of pivotal importance in countless industrial and medical appliances. Fluctuations in thermophysical properties of such fluids due to variations in temperature have not received due attention in the available literature. Present investigation aims to fill this void by analyzing the flow of copper-water nanofluid with temperature dependent viscosity past a Riga plate. Strong wall suction and viscous dissipation have also been taken into account. Numerical solutions for the resulting nonlinear system have been obtained. Results are presented in the graphical and tabular format in order to facilitate the physical analysis. An estimated expression for skin friction coefficient and Nusselt number are obtained by performing linear regression on numerical data for embedded parameters. Results indicate that the temperature dependent viscosity alters the velocity as well as the temperature of the nanofluid and is of considerable importance in the processes where high accuracy is desired. Addition of copper nanoparticles makes the momentum boundary layer thinner whereas viscosity parameter does not affect the boundary layer thickness. Moreover, the regression expressions indicate that magnitude of rate of change in effective skin friction coefficient and Nusselt number with respect to nanoparticles volume fraction is prominent when compared with the rate of change with variable viscosity parameter and modified Hartmann number.

The Characteristics of Chinese Traditionality Expression in View of Spatial Elements at Restaurants in Beijing Area (베이징지역 레스토랑 공간구성요소에 나타난 중국 전통성 표현 특성 연구)

  • Yuan, DanDan;Oh, Hye Kyung
    • Korean Institute of Interior Design Journal
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    • v.25 no.1
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    • pp.163-171
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    • 2016
  • The objectives of this study is to analyze the characteristics of Chinese traditionality expression at restaurants in Beijing area. 12 restaurants were selected and visited for the investigation research. The results were as follows. First, traditional reproduction was found mainly manifested through the reproduction of traditional ornaments, in particular, the facade and interior element ornaments. Second, Traditional transformation was mainly manifested in replacement material while changing the shape slightly, or to stretch or shorten prototype shape and other negative deformation methods which did not largely out of the scope of traditional reproduction. Third, Traditional reinterpretation was expressed by abstract, symbol or metaphor on designs, usually people can not directly recognize the traditional archetype. When compare with traditional reproduction or traditional transformation, traditional reinterpretation was relatively fewer, however, in this study the traditional reinterpretation and traditional transformation have same numerical result. Reinterpretation as a positive performance method of traditional modernized, it was encouraging the phenomenon, especially in the ceiling design. Chinese traditional cloud patterns have been three-dimensional and diversification of use. And in the wall design, traditional elements have been extremely simplistic or adopted a wide variety of traditional elements, it may be preferred in diversity. In addition, furniture was tinge traditional elements in modern form, lighting was added symbolize color or picture on the traditional lighting which shape was simplified to emphasize space's traditional. But the facade, sign board, floor, and window element seems the range of variation was not wild, promote more use the positive traditional reinterpretation method.

The solar cell modeling using Lambert W-function (Lambert W 함수를 이용한 태양전지 모델링)

  • Bae, Jong-Guk;Kang, Gi-Hwan;Kim, Kyung-Soo;Yu, Gwon-Jong;Ahn, Hyung-Geun;Han, Deuk-Young
    • 한국태양에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.278-281
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    • 2011
  • This system can predict the maximum output about all illumination levels so that the PV system designer can design the system having the best efficiency. For the output prediction exact about the solar cell, that is the device the basis most in the PV system, the basis has to be in order to try this way. The solution based on Lambert W-function are presented to express the transcendental current-voltage characteristic containing parasitic power consuming parameters like series and shunt resistances. A simple and efficient method for the extraction of a single current-voltage (I-V) curve under the constant illumination level is proposed. With the help of the Lambert W function, the explicit analytic expression for I is obtained. And the explicit analytic expression for V is obtained. This analytic expression is directly used to fit the experimental data and extract the device parameters. The I-V curve of the solar cell was expressed through the modeling using Lambert W-function and the numerical formula where there is the difficulty could be logarithmically expressed This method expresses with the I-V curve through the modeling using Lambert W-function which adds other loss ingredients to the equation2 as to the research afterward. And the solar cell goes as small and this I-V curve can predict the power penalty in the system unit.

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On the effect of porosity on the shear correction factors of functionally graded porous beams

  • Ben Abdallah Medjdoubi;Mohammed Sid Ahmed Houari;Mohamed Sadoun;Aicha Bessaim;Ahmed Amine Daikh;Mohamed-Ouejdi Belarbi;Abdelhak Khechai;Aman Garg;Mofareh Hassan Ghazwani
    • Coupled systems mechanics
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    • v.12 no.3
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    • pp.199-220
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    • 2023
  • This article presents a new analytical model to study the effect of porosity on the shear correction factors (SCFs) of functionally graded porous beams (FGPB). For this analysis, uneven and logarithmic-uneven porosity functions are adopted to be distributed through the thickness of the FGP beams. Critical to the application of this theory is a determination of the correction factor, which appears as a coefficient in the expression for the transverse shear stress resultant; to compensate for the assumption that the shear strain is uniform through the depth of the cross-section. Using the energy equivalence principle, a general expression is derived from the static SCFs in FGPB. The resulting expression is consistent with the variationally derived results of Reissner's analysis when the latter are reduced from the two-dimensional case (plate) to the one-dimensional one (beam). A convenient algebraic form of the solution is presented and new study cases are given to illustrate the applicability of the present formulation. Numerical results are presented to illustrate the effect of the porosity distribution on the (SCFs) for various FGPBs. Further, the law of changing the mechanical properties of FG beams without porosity and the SCFare numerically validated by comparison with some available results.

A Study on the Expression of Numerical Data by the KAS Multimedia Tool (멀티미디어 저작도구 카스에 의한 수치데이터 표현에 관한 연구)

  • 김상호;이영욱
    • Journal of the Korea Society of Computer and Information
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    • v.4 no.3
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    • pp.1-7
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    • 1999
  • This study is to design and implement the synthetic courseware that covers repeating learning, individual teaching, and effective teaching-learning games by using multimedia authoring tool KAS for numerical data of computer science which is especially a little boring and difficult to understand through blackboard-based lesson for senior high school students. It also overcomes the drawbacks of the existing CAI focused on text and image by combining various kinds of media like image, animation and sound effects. Animation of numerical data in the fields of radix conversion makes it possible for learners to check the individual learning process and visual interest. So it comes to increase the effectiveness of learning. Whenever each chapter is finished. learners' understanding can be evaluated by formative test. Applicability test of the developed CAI in Eumsung Senior High School. is statistically evaluated as more effective than that of the blackboard-based lesson.

[ $H_{\infty}$ ] Filtering for Descriptor Systems

  • Chen, Yue-Peng;Zhou, Zu-De;Zeng, Chun-Nian;Zhang, Qing-Ling
    • International Journal of Control, Automation, and Systems
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    • v.4 no.6
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    • pp.697-704
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    • 2006
  • The paper is concerned with $H_{\infty}$ filtering for descriptor systems. A necessary and sufficient condition is established in terms of linear matrix inequalities(LMIs) for the existence of normal filters such that the error systems are admissible and the transfer function from the disturbance to the filtering error output satisfies a prescribed $H_{\infty}$-norm bound constraint. When these LMIs are feasible, an explicit parameterization expression of all desired normal filter is given. All these results are yielded without decomposing the original descriptor systems, which makes the filter design procedure simple and direct. Finally, a numerical example is derived to demonstrate the applicability of the proposed approach.

The analytical solution for buckling of curved sandwich beams with a transversely flexible core subjected to uniform load

  • Poortabib, A.;Maghsoudi, M.
    • Structural Engineering and Mechanics
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    • v.52 no.2
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    • pp.323-349
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    • 2014
  • In this paper, linear buckling analysis of a curved sandwich beam with a flexible core is investigated. Derivation of equations for face sheets is accomplished via the classical theory of curved beam, whereas for the flexible core, the elasticity equations in polar coordinates are implemented. Employing the von-Karman type geometrical non-linearity in strain-displacement relations, nonlinear governing equations are resulted. Linear pre-buckling analysis is performed neglecting the rotation effects in pre-buckling state. Stability equations are concluded based on the adjacent equilibrium criterion. Considering the movable simply supported type of boundary conditions, suitable trigonometric solutions are adopted which satisfy the assumed edge conditions. The critical uniform load of the beam is obtained as a closed-form expression. Numerical results cover the effects of various parameters on the critical buckling load of the curved beam. It is shown that, face thickness, core thickness, core module, fiber angle of faces, stacking sequence of faces and openin angle of the beam all affect greatly on the buckling pressure of the beam and its buckled shape.