• 제목/요약/키워드: Analysis and Analogy

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고온 초전도 자속흐름 트랜지스터에 적용된 전자냉각 특성 시뮬레이션 (Characteristics Simulation of Electronics Cooling for a High-Temperature Superconducting Flux Flow Transistor Circuit)

  • 고석철;강형곤;임성훈;두호익;이종화;한병성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.1063-1066
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    • 2002
  • An equivalent circuit for the superconductor flux flow transistor(SFFT) was combined with high temperature cooling device, based on the analogy between thermal and electrical variables using the high-temperature superconductor(HTS), is proposed. The device is composed of parallel weak links with a nearby magnetic control line. A model has been developed that is based on solving the equation of motion of Abrikosov vortices subject to Lorentz viscous and pinning forces as well as magnetic surface barriers. The use of thermal models the global performance of thermal cooling circuit and signal system to be checked by using electrical circuit analysis programs such as SPICE.

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The New Substituent Constants in the Excited States (II)

  • Sang-Chul Shim;Joon-Won Park;Heui-Suk Ham;Jin-Soon Chung
    • Bulletin of the Korean Chemical Society
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    • 제4권1호
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    • pp.45-47
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    • 1983
  • In order to standardize the ${\sigma}^*,\;{\rho}^*$ is taken as unity for the benzoic acids by analogy with the fact that ${\rho}$ of benzoic acids in the ground state is taken as unity. The $pK_{\alpha}^*$ of many benzoic acid derivatives are determined by UV spectroscopy and fluorescence spectral analysis whenever possible. The ${\sigma}^*$ constants are derived from the Hammett equation utilizing these $pK_{\alpha}^*$ values and the $pK_{\alpha}^*$ of the benozic acid derivatives showed better correlationship with ${\sigma}^*$ than ${\sigma},\;{\sigma}^+\;and\;{\sigma}^-$ as expected. From these ${\sigma}^*$ values, ${\rho}^*$ of the phenol derivatives was calculated to be 1.28. The new standardized ${\sigma}^*$ values are calculated from the $pK_{\alpha}^*$ values of phenols since more accurate and abundant data are available for phenols than the benzoic acid derivatives.

품질의 이원론을 이용한 개선의 우선순위 결정 (Determination of Priority for Improvement Using the Theory of Two-dimensional Quality)

  • 송해근
    • 산업경영시스템학회지
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    • 제36권1호
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    • pp.70-77
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    • 2013
  • The theory of two-dimensional quality, in particular, the Kano model that is developed by the analogy with the M-H theory, has been applied in various industry fields for more than three decades. Importance-Performance Analysis (IPA) assumes that the degree of physical fulfilment of quality attributes and the satisfaction of that attribute is linear, and therefore, it is applicable to the traditional one-dimensional attribute, not other quality types defined in the Kano's model such as attractive or must-be attribute. To solve this problem, the current study suggests a new importance-satisfaction analysis using a modified IPA in accordance with the three quality types and a diagonal method introduced by Slack (1999) to determine improvement priority. For this, I investigated 19 smartphone's quality attributes and conducted a survey of 334 university students for the results of Kano's model, which adopted from Song and Park (2012)'s study, and the importance/satisfaction of the quality attributes and the results of the priority for improvement of the 19 quality attributes. The results show that the proposed I-S priority model is better than the conventional IPA based on the comparison results of determination coefficient from the regression analysis of the two models.

인간 면역 체계를 이용한 네트워크 탐지기술 연구 (A Study on Network detection technique using Human Immune System)

  • 김정원;;정길호;최종욱
    • 한국데이타베이스학회:학술대회논문집
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    • 한국데이타베이스학회 1999년도 춘계공동학술대회: 지식경영과 지식공학
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    • pp.307-313
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    • 1999
  • This paper reviews and assesses the analogy between the human immune system and network intrusion detection systems. The promising results from a growing number of proposed computer immune models for intrusion detection motivate this work. The paper begins by briefly introducing existing intrusion detection systems (IDS's). A set of general requirements for network-based IDS's and the design goals to satisfy these requirements are identified by a careful examination of the literature. An overview of the human immune system is presented and its salient features that can contribute to the design of competent network-based IDS's are analysed. The analysis shows that the coordinated actions of several sophisticated mechanisms of the human immune system satisfy all the identified design goals. Consequently, the paper concludes that the design of a novel network-based IDS based on the human immune system is promising for future network-based IDS's

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완충기를 가진 로봇다리의 동역학 해석 및 동적 보행제어 (Dynamic analysis and control of a robot leg with a shock absorber)

  • 오창근;강성철;이수용;김문상;유홍희
    • 대한기계학회논문집A
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    • 제22권4호
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    • pp.768-778
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    • 1998
  • Human beings usually absorb a shock from terrain during walking through the damping effects of joints, muscles and skin. With this analogy, a robot-leg with a shock absorber is built to absorb the impact forces at its foot during high-speed walking on irregular terrain. To control the hip position while walking, the dynamic controller suitable for high speed walking is designed and implemented based on a dynamic model by Kane's equation. The hip position tracking performances of various controllers (PID controller, computed torque controller and feedforward torque controller) are compared through the experiments of the real robot-leg.

인간 면역 체계를 이용한 네트워크 탐지기술 연구 (A Study on Network detection technique using Human Immune System)

  • 김정원;;정길호;최종욱
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 1999년도 춘계공동학술대회-지식경영과 지식공학
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    • pp.307-313
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    • 1999
  • This paper reviews and assesses the analogy between the human immune system and network intrusion detection systems. The promising results from a growing number of proposed computer immune models for intrusion detection motivate this work. The paper begins by briefly introducing existing intrusion detection systems (IDS's). A set of general requirements for network-based IDS's and the design goals to satisfy these requirements are identified by a careful examination of the literature. An overview of the human immune system is presented and its salient features that can contribute to the design of competent network-based IDS's are analysed. The analysis shows that the coordinated actions of several sophisticated mechanisms of the human immune system satisfy all the identified design goals. Consequently, the paper concludes that the design of a network-based IDS based on the human immune system is promising for future network-based IDS's

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Chicken Disease Characterization by Fluorescence Spectroscopy

  • Kang S.;Kim M. S.;Kim I.
    • Agricultural and Biosystems Engineering
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    • 제5권1호
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    • pp.25-29
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    • 2004
  • Fluorescence spectroscopy was used to characterize chicken carcass diseases. Spectral signatures of three different disease categories of poultry carcasses (airsacculitis, cadaver and septicemia) were obtained from fluorescence emission measurements in the wavelength range of 360 to 600 nm with 330 nm excitation. Principal Component Analysis (PCA) was used to select the most significant wavelengths for the classification of poultry carcasses. These wavelengths were analyzed for pathologic correlation of poultry diseases. Using a Soft Independent Modeling of Class Analogy (SIMCA) of principal components with a Mahalanobis distance metric, poultry carcasses were individually classified into different classes with $97.9\%$ accuracy.

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Torsional rigidity of arbitrarily shaped composite sections by hybrid finite element approach

  • Darllmaz, Kutlu;Orakdogen, Engin;Girgin, Konuralp;Kucukarslan, Semih
    • Steel and Composite Structures
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    • 제7권3호
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    • pp.241-251
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    • 2007
  • The purpose of this study is to calculate the torsional rigidity of arbitrarily shaped composite sections on the basis of hybrid finite element approach. An analogy is used between the torsion problem and deformation of a plate which exhibits only shear behavior. In the analysis a simple hybrid finite element based on Hellinger-Reissner functional is presented and a set of numerical examples are performed to demonstrate and asses the performance of the developed element in practical applications.

와류이탈 위상차를 이용한 사보니우스형 풍력터빈의 소음 저감 설계에 관한 수치적 연구 (Numerical analysis on the low noise designs of Savonius wind turbines by using phase difference in vortex shedding)

  • 김상현;정철웅
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2013년도 춘계학술대회 논문집
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    • pp.166-171
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    • 2013
  • In this study, low noise designs of a Savonius wind turbines are numerically investigated. From a previous study, it was found that the high harmonic components whose fundamental frequency is higher than the BPF were found to be dominant in noise spectrum of a Savonius wind turbine. On a basis of this observation, S-shaped blade tip is proposed as a low design factors that decrease wind turbine noise by inducing phase differences in vortex shedding. The conventional Savonius and S-shaped turbines are investigated using Hybrid CAA method where flow field around the turbine are computed using CFD techniques and the radiated noise are predicted by applying acoustic analogy to the computed flow data. Noise reductions by these design factors are confirmed by comparing the predicted noise levels from these turbines.

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An efficient Galerkin meshfree analysis of shear deformable cylindrical panels

  • Wang, Dongdong;Wu, Youcai
    • Interaction and multiscale mechanics
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    • 제1권3호
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    • pp.339-355
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    • 2008
  • A Galerkin meshfree method is presented for analyzing shear deformable cylindrical panels. Based upon the analogy between the cylindrical panel and the curved beam a pure bending mode for cylindrical panel is rationally constructed. The meshfree approximation employed herein is characterized by an enhanced moving least square or reproducing kernel basis function that can exactly represent the pure bending mode and thus meets the requirement of Kirchhoff mode reproducing condition. The variational form is discretized using the efficient stabilized conforming nodal integration with a smoothed nodal gradient based curvature. The resulting meshfree formulation satisfies the integration constraint for bending exactness. Moreover, it is shown here that the smoothed gradient preserves several desired properties which are valid for the standard gradient obtained by direct differentiation, such as partition of nullity and reproduction of a constant strain field. The efficacy of the proposed approach is demonstrated by two benchmark cylindrical panel examples.