• Title/Summary/Keyword: first-principle approach

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Sources of Evoking Frustration, Actions to Overcome the Frustration and Preference of Design Aesthetic Principle in Product Choice (좌절감정의 원인 및 극복행동과 제품선택에서 디자인의 심미성 선호)

  • Lim, Ah Young;Choi, Nak Hwan
    • Science of Emotion and Sensibility
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    • v.17 no.4
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    • pp.109-122
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    • 2014
  • The present study focused on frustration emotion investigated the variables evoking frustration and the process in which sense of frustration would be overcome, and explored the principle of aesthetics the consumers under the frustration might prefer in choosing goods. The results of this study are as follows. First, consumers usually felt frustration rather than anger when it became obvious that their objectives could not be met and that they failed to achieve their objectives due to uncontrollable cause. Second, consumers who felt frustration wanted to receive emotional support and comfort from close acquaintances rather than to cope actively with the unsuccessful situation by renewed challenges. Third, consumers, once frustrated, preferred harmony principle rather than emphasis principle in terms of esthetics in choosing design of goods. Therefore, marketing managers are advised to approach to the consumers who felt frustration on the basis of harmony principle in design of goods.

Nonlinear Process Model Based Control of Drum-type Cogeneration Power Plant (비선형 PMBC에 의한 드럼형 열병합발전소 제어)

  • 조영춘;남해곤;이광식;윤성훈
    • Journal of Energy Engineering
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    • v.4 no.3
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    • pp.364-371
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    • 1995
  • 100MW급 유류 연소 드럼형 열병합발전소의 주증기온도와 드럼수위 제어를 위한 비선형 PMBC를 개발하고 그 성능을 PID 알고리즘과 비교하였다. "first principle" approach를 사용하여 개발된 프로세스 모델은 정상상태를 과도상태에서 그 정확도를 현장의 데이터와 비교 검증한 것으로 제어기 성능 평가와 설계에 적합한 정교한 것이다. PMBC와 PID 제어의 성능을 부하증가와 연료의 열량변화 등의 외란에 비교한 결과, PMBC가 PID에 비하여 속응성, 절대오차 적분차, 제어노력 등에서 월등하게 우수한 것을 확인하였다. 것을 확인하였다.

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Network Enlarging Search Technique (NEST) for the Crew Scheduling Problem

  • Paek, Gwan-Ho
    • Journal of the Korean Operations Research and Management Science Society
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    • v.19 no.2
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    • pp.177-198
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    • 1994
  • We consider an algorithm for the Crew Scheduling Problem (CSP) based on the Transportation Problem approach. The main flows of the algorithm are arranged in three steps. First we propose a heuristic algorithm of the greedy principle to obtain an initial feasible solution. Secondary we present a method of formulating CSP into a Modified Transportation Problem format. Lastly the procedures of network search to get the optimal solution are presented. This algorithm can be applied to the general GSP and also to most combinatorial problems like the Vehicle Routing Problems. The computational results show that the large size CSP's could be tackled.

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열병합발전소 주증기온도 제어를 위한 비선형 PMBC

  • 조영춘;남해곤;이광식;윤성훈
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1995.05a
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    • pp.163-172
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    • 1995
  • 100 MW급 유류연소 드럼형 열병합발전소의 주증기온도 제어를 위한 비선형 process model based control (PMBC)을 개발하고 그 성능을 PID 알고리즘과 비교하였다. 비선형 PMBC에서는 프로세스의 메캐니즘을 비교적 충실히 반영하는 모델이 필요한데, 사용된 모델은 first principle approach를 사용하여 개발된 것으로 제어기 성능 평가와 설계에 적합한 정교한 것이다. 비선형 PMBC는 비선형 피드백, feedforward, decoupling을 제공하고 분산제어에 적합하면서 모델링 오차에 민감하지 않은 장점이 있다. PMBC와 PID 제어의 성능을 부하증가와 연료의 열량변화등의 외란에 비교한 결과, PMBC가 PID에 비하여 속응성, 절대오차 적분치, 제어노력등에서 월등하게 우수한 것을 확인하였다.

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A Study on the Historic-Genetic Principle of Mathematics Education(1) - A Historic-Genetic Approach to Teaching the Meaning of Proof (역사발생적 수학교육 원리에 대한 연구(1) - 증명의 의미 지도의 역사발생적 전개)

  • 우정호;박미애;권석일
    • School Mathematics
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    • v.5 no.4
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    • pp.401-420
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    • 2003
  • We have many problems in the teaching and learning of proof, especially in the demonstrative geometry of middle school mathematics introducing the proof for the first time. Above all, it is the serious problem that many students do not understand the meaning of proof. In this paper we intend to show that teaching the meaning of proof in terms of historic-genetic approach will be a method to improve the way of teaching proof. We investigate the development of proof which goes through three stages such as experimental, intuitional, and scientific stage as well as the development of geometry up to the completion of Euclid's Elements as Bran-ford set out, and analyze the teaching process for the purpose of looking for the way of improving the way of teaching proof through the historic-genetic approach. We conducted lessons about the angle-sum property of triangle in accordance with these three stages to the students of seventh grade. We show that the students will understand the meaning of proof meaningfully and properly through the historic-genetic approach.

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Free vibration analysis of a sandwich cylindrical shell with an FG core based on the CUF

  • Foroutan, Kamran;Ahmadi, Habib;Carrera, Erasmo
    • Smart Structures and Systems
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    • v.30 no.2
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    • pp.121-133
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    • 2022
  • An analytical approach for the free vibration behavior of a sandwich cylindrical shell with a functionally graded (FG) core is presented. It is considered that the FG distribution is in the direction of thickness. The material properties are temperature-dependent. The sandwich cylindrical shell with a FG core is considered with two cases. In the first model, i.e., Ceramic-FGM-Metal (CFM), the interior layer of the cylindrical shell is rich metal while the exterior layer is rich ceramic and the FG material is located between two layers and for the second model i.e., Metal-FGM-Ceramic (MFC), the material distribution is in reverse order. This study develops Carrera's Unified Formulation (CUF) to analyze sandwich cylindrical shell with an FG core for the first time. Considering the Principle of Virtual Displacements (PVDs) according to the CUF, the dependent boundary conditions and governing equations are obtained. The coupled governing equations are derived using Galerkin's method. In order to validate the present results, comparisons are made with the available solutions in the previous researches. The effects of different geometrical and material parameters on the free vibration behavior of a sandwich cylindrical shell with an FG core are examined.

Prediction of Ultra-High ON/OFF Ratio Nanoelectromechanical Switching from Covalently Bound $C_{60}$ Chains

  • Kim, Han Seul;Kim, Yong-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.645-645
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    • 2013
  • Applying a first-principles computational approach combining density-functional theory and matrix Green's function calculations, we have studied the effects [2+2] cycloaddition olligormerization of fullerene $C_{60}$ chains on their junction charge transport properties. Analyzing first the microscopic mechanism of the switching realized in recent scanning tunneling microscope (STM) experiments, we found that, in agreement with experimental conclusions, the device characteristics are not significantly affected by the changes in electronic structure of $C_{60}$ chains. It is further predicted that the switching characteristics will sensitively depend on the STM tip metal species and the associated energy level bending direction in the $C_{60}-STM$ tip vacuum gap. Considering infinite $C_{60}$ chains, however, we confirm that unbound $C_{60}$ chains with strong orbital hybridizations and band formation should in principle induce a much higher conductance state. We demonstrate that a nanoelectromechanical approach in which the $C_{60}-STM$ tip distance is maintained at short distances can achieve a metal-independent and drastically improved switching performance based on the intrinsically better electronic connectivity in the bound $C_{60}$ chains.

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An Approach for a Substitution Matrix Based on Protein Blocks and Physicochemical Properties of Amino Acids through PCA

  • You, Youngki;Jang, Inhwan;Lee, Kyungro;Kim, Heonjoo;Lee, Kwanhee
    • Interdisciplinary Bio Central
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    • v.6 no.4
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    • pp.3.1-3.10
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    • 2014
  • Amino acid substitution matrices are essential tools for protein sequence analysis, homology sequence search in protein databases and multiple sequence alignment. The PAM matrix was the first widely used amino acid substitution matrix. The BLOSUM series then succeeded the PAM matrix. Most substitution matrixes were developed by using the statistical frequency of substitution between each amino acid at blocks representing groups of protein families or related proteins. However, substitution of amino acids is based on the similarity of physiochemical properties of each amino acid. In this study, a new approach was used to obtain major physiochemical properties in multiple sequence alignment. Frequency of amino acid substitution in multiple sequence alignment database and selected attributes of amino acids in physiochemical properties database were merged. This merged data showed the major physiochemical properties through principle components analysis. Using factor analysis, these four principle components were interpreted as flexibility of electronic movement, polarity, negative charge and structural flexibility. Applying these four components, BAPS was constructed and validated for accuracy. When comparing receiver operated characteristic ($ROC_{50}$) values, BAPS scored slightly lower than BLOSUM and PAM. However, when evaluating for accuracy by comparing results from multiple sequence alignment with the structural alignment results of two test data sets with known three-dimensional structure in the homologous structure alignment database, the result of the test for BAPS was comparatively equivalent or better than results for prior matrices including PAM, Gonnet, Identity and Genetic code matrix.

Form Generation of Structural Bridges based on Geometric Approach (기하학적 접근법에 의한 교량구조의 형태생성)

  • Kim, Nam-Hee;Koh, Hyun-Moo;Hong, Sung-Gul
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.23 no.4
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    • pp.379-386
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    • 2010
  • In conceptual design stage it is important to develop structural forms freely. However, structural engineers are prompt to consider types of structural systems following load paths rather than to imagine various forms. This study attempts to expand the limit of imagination that was blocked within engineering approach newly from geometric perspective view. First of all, existing bridge structures are reviewed in terms of geometric vocabulary. Some bridge forms showing apparent geometric features are regenerated through the geometric approach proposed in this study. This study is not to develop geometric principle to build new structural forms, but to propose the geometric approach to generate design alternatives using the well established geometry concepts.

Computational electromechanical approach for stability/instability of smart system actuated with piezoelectric NEMS

  • Luo, Zhonghua;Cheng, Xiaoling;Yang, Yuhan
    • Advances in Computational Design
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    • v.7 no.3
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    • pp.211-227
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    • 2022
  • In this research, the size-dependent impact of an embedded piezoelectric nanoplate subjected to in-plane loading on free vibration characteristic is studied. The foundation is two-parameter viscoelastic. The nonlocal elasticity is employed in order to capture the influence of size of the plate. By utilizing Hamilton's principle as well as the first- order shear deformation theory, the governing equation and boundary conditions are achieved. Then, using Navier method the equations associated with the free vibration of a plate constructed piezoelectric material under in-plane loads are solved analytically. The presented formulation and solution procedure are validated using other papers. Also, the impacts of nonlocal parameter, mode number, constant of spring, electric potential, and geometry of the nanoplate on the vibrational frequency are examined. As this paper is the first research in which the vibration associated with piezoelectric nanoplate on the basis of FSDT and nonlocal elasticity is investigated analytically, this results can be used in future investigation in this area.