• Title/Summary/Keyword: Theory vs Application

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Recent Development of Reliability Engineering and Research Trend Analysis in Korea (최근 국내 신뢰성 공학의 발전과 연구 동향 및 분석)

  • Lim, Ik Sung
    • Journal of Applied Reliability
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    • v.13 no.4
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    • pp.253-271
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    • 2013
  • Since The Korean Reliability Society had been founded in 1999, development history of reliability engineering in Korea is reviewed and research outputs and papers from 2008 to current are analyzed in terms of types of industry, product life cycle, hardware vs software, and theory vs application. The purpose of this research is to review the recent reliability engineering research conducted in Korea including development history as well as published papers to identify the weakness and/or deficiencies in order to suggest the future research directions, which would contribute the development of industries in Korea.

Robust Servo Design and Application for Optical Disk Drive using Robust Control Theory: QFT vs. H_inf (광 디스크 서보 설계를 위한 강건 제어 이론의 적용 및 평가: QFT vs. $H_{\infty}$)

  • Choi, Jin-Young;Park, Tae-Wook;Yang, Hyun-Seok;Park, No-Cheol;Park, Young-Pil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.541-546
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    • 2005
  • In this paper, the various uncertainties, which are generated in working of an optical disk drive, are discussed in details and the robust servo design considering the uncertainties are discussed. First, the classification of the uncertainties and the modeling process including that are treated. Then, the robust servo designs using QFT and $H_{\infty}$ theory are performed. Finally, the designed servo loops realized by DSP are applied to the real system. From these experiments, we proved that the robust servo design using QFT and $H_{\infty}$ have a good performance and a good robust stability when it compared with the conventional servo loop.

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Robust Servo Design and Application for Optical Disk Drive Using Robust Control Theory : H vs. QFT (광 디스크 드라이브 서보 설계를 위한 강건 제어 이론의 적용 및 평가 : H vs. QFT)

  • Lee, Kwang-Hyun;Yang, Hyunseok;Park, No-Cheol;Park, Young-Pil;Choi, Jin-Young
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.10 s.103
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    • pp.1148-1159
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    • 2005
  • In this paper, the various uncertainties generated in an optical disk drive (ODD) and the robust servo designs considering the uncertainties are studied. First, the brief introduction an ODD and the servo error tolerance of it are discussed. Then, the classifications of uncertainty and the concept of relative stability are introduced. Considering the uncertainty of an ODD, two robust control approaches are applied: (i) mixed sensitivity approach in H$\infty$ control theory for unstructured uncertainty, (ii) QFT for structured uncertainty Finally, the designed controllers are realized by DSP, and these controllers are applied to a commercial DVD-ROM drive. From these experiments, we prove that the designed robust controllers have more good disturbance rejection performance and robustness when it is compared to the conventional lead-lag controller.

Sound Energy Distributions according to Incident Angles on the Bounding Surfaces in the Reverberation Room (잔향실 경계면에서 입사각에 따른 음에너지 분포)

  • 강현주;이정권;김현실;김재승;김상렬
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1997.10a
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    • pp.279-285
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    • 1997
  • In this paper, the validity for the application of the diffuse sound field theory to the real sound filed, especially on the bounding surfaces of the rooms, was studied. Numerical simulations using ray tracing technique for two models, namely spheres and a reverberant room, were performed. Calculation results show that the distribution of the incident sound energy vs incident angles is approximated to Gaussian distribution, not to the uniform distribution.

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The Approaches of Cultural Studies to Theatre -The Limits of Theory Application- (연극에 대한 문화연구적 접근 -'이론' 도입의 한계를 중심으로-)

  • Kim, Yongn Soo
    • Journal of Korean Theatre Studies Association
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    • no.40
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    • pp.307-344
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    • 2010
  • Cultural Studies built on the critical mind of New Left exposes the relationship between culture and power, and investigates how this relationship develops the cultural convention. It has achieved the new perspective that could make us to think culture and art in terms of political correctness. However, the critical voices against the theoretical premises of Cultural Studies have been increased as its heyday in 1980s was nearly over. For instance, Terry Eagleton, a former Marxist literary critic, declared in 2003 that the golden age of cultural theory is long past. This essay, therefore, intends to show the weak foundations on which the approaches of cultural studies to theatre rest and to clarify the general problem of their introduction to theatre studies. The approach of cultural studies to theatre takes the form of 'top-down inquiry' as it applies a theory to a particular play or historical period. In other word, from the theory the writer moves to the particular case. The result is not an inquiry but rather a demonstration. This circularity can destroy the point of serious intellectual investigation as the theory dictates answers. The goal-oriented narrow viewpoint as a logical consequence of 'top-down inquiry' makes the researcher to favor the plays or the parts of a play that are proper to test a theory. As a result it loses the fair judgment on the artistic value of a play, and brings about the misinterpretation. The interpreter-oriented reading is the other defect of cultural studies as it disregards the inherent meaning of the text, distorting a play. The approach of cultural studies also consists of a conventionality as it arrives at a stereotyped interpretation by using certain conventions of reasoning and rhetoric. The cultural theories are fundamentally the 'outside theories' that seek to explain not theatre but the very broad features of society and politics. Consequently their application to theatre risks the destructive criticism, disregarding the inherent experience of theatre. Most of, if not all, cultural theories, furthermore, are proven to be lack of empirical basis. The alternative method to them is a 'cognitive science' that proves scientifically our mind being influenced by bodily experience. The application of cultural materialism to Shakespeare's is one of the cases that reveal the limits of cultural studies. Jonathan Dollimore and Water Cohen provide a kind of 'canonical study' in this application that is imitated by the succeeding researchers. As a result the interpretation of has been flooded with repetitive critical remarks, revealing the problem of 'top-down inquiry' and conventional reasoning. Cultural Studies is antipodal to theatre in some respect. It is interested chiefly in the social and political reality while theatre aims to create the fiction world. The theatre studies, therefore, may have to risk the danger of destroying its own base when it adopts cultural studies uncritically. The different stance between theatre and cultural theories also occurs from the opposition of humanism vs. antihumanism. We have to introduce cultural theories selectively and properly not to destroy the inherent experience and domain of theatre.

Application of Flory-Treszczanowicz-Benson model and Prigogine-Flory-Patterson theory to Excess Molar Volumes of Isomers of Propanol with Cyclohexane or n-Hexane

  • Gahlyan, Suman;Verma, Sweety;Rani, Manju;Maken, Sanjeev
    • Korean Chemical Engineering Research
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    • v.56 no.4
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    • pp.536-541
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    • 2018
  • Excess molar volumes ($V_m^E$) of binary mixtures of 1-propanol or 2-propanol (1) + cyclohexane or n-hexane (2) were measured with V-shaped dilatometer at 303.15 K. The $V_m^E$ data for these mixtures varied as: 2-propanol > 1-propanol and were higher for cyclohexane than n-hexane for both propanol systems. The experimental data were correlated with Redlich-Kister polynomial. The $V_m^E$ data were interpreted qualitatively as well as quantitatively in terms of Flory-Treszczanowicz-Benson model and Prigogine-Flory-Patterson theory. Both models correctly described the sign and shape of $V_m^E$ vs $x_1$ curves. The values calculated by both the models agree well with the experimental data.

Application of Flory-Treszczanowicz-Benson model and Prigogine-Flory-Patterson theory to Excess Molar Volume of Binary Mixtures of Ethanol with Diisopropyl Ether, Cyclohexane and Alkanes (C6-C9)

  • Kashyap, Pinki;Rani, Manju;Tiwari, Dinesh Pratap;Park, So-Jin
    • Korean Chemical Engineering Research
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    • v.58 no.2
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    • pp.257-265
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    • 2020
  • Densities (ρ) for binary mixtures of ethanol (1) + diisopropyl ether (DIPE) or cyclohexane or alkane (C6-C9) (2) were measured at 298.15 K, 308.15 K and 318.15 K. The excess molar volume (VEm) of binary mixtures was calculated using ρ data and correlated with Redlich-Kister polynomial equation. The VEm values for binary mixtures of ethanol (1) + cyclohexane or n-alkane (C6-C9) (2) were positive, whereas for ethanol (1) + DIPE (2) these were negative. The magnitude of VEm values follows the order: cyclohexane > n-nonane > n-octane > n-heptane > n-hexane > DIPE. The VEm values have been interpreted qualitatively and also quantitatively in terms of Flory-Treszczanowicz-Benson (FTB) model and Prigogine-Flory-Patterson (PFP) theory. The values VEm predicted using FTB model agree well with experimental VEm values at all mole fractions. But the PFP theory describes well VEm data in ethanol-rich region (x1 > 0.5) for all binary mixtures and is able to predict the sign of VEm vs x1 curve for ethanol-lean region (x1 < 0.5) except for ethanol (1) + nonane (2) mixtures.

A Study on User Liking Based on Anthropomorphism of Virtual Humans:Focusing on Social Comparison Experience and Self-Improvement Motivation (가상인간의 의인화에 따른 이용자 호감도에 관한 연구: 사회비교 경험과 자기향상욕구를 중심으로)

  • Jeong, DongA;Kim, Hayeon;Lee, Sang Woo
    • The Journal of Information Systems
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    • v.32 no.4
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    • pp.163-188
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    • 2023
  • Purpose The study examines the impact of the level of anthropomorphism (both in appearance and behavior) of virtual humans on user liking. It investigates whether this relationship is mediated by social comparison experiences, with the moderated mediation effect of users' desire for self-improvement. Design/methodology/approach A between-groups experimental design was employed to examine the impact of different levels of appearance(low/mid/high) and behavior(low/high) anthropomorphism on user liking of virtual humans. The experiment was conducted in an online environment, and participants were randomly exposed to one of six stimuli, which were Instagram-like posts. Findings The results indicate that as virtual humans become more anthropomorphic, they have a positive impact on user liking. However, once the level of anthropomorphism in appearance reaches a certain point (mid vs high), there is no significant difference in user liking. Users who perceive virtual humans as highly anthropomorphic tend to engage in more social comparison experiences, which positively affects their liking for these virtual humans. Conversely, individuals with a high desire for self-improvement found that the positive effect of appearance anthropomorphism on liking through social comparison experiences was reduced. The study extends the application of social comparison theory by examining its impact on influencer marketing with virtual beings. It provides valuable insights for the formulation of influencer marketing strategies using virtual humans.

Vizrt Engine-Based Virtual Reality Graphics Algorithm A Study on the Basic Practical Training Method (Vizrt 엔진 기반 가상현실 그래픽 알고리즘과 기초 실습 교육 방식의 연구)

  • Cho, Hyun Kyung
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.3
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    • pp.197-202
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    • 2019
  • In the era of the fourth revolution, interest in content production using proven engines in the broadcasting sector, such as Vizrt, is growing. The new visual effects required in the 5G era are critical to content production training. Vizrt has a good production time utility and affordability for broadcast and media content. In this paper, we are going to use this to present a practical case of the theorem and application of the basic training course in the production of virtual content, and to present the basic training direction. In the introduction, the graphic algorithm analyzed and studied the characteristics and environmental factors of the Vizrt engine. In this paper, the production process was studied separately, and the work carried out through engine implementation was presented. The VS Studio Foundation was provided as a practical production case at each stage. The Vizrt engine operator process is important in graphic approach and application, and through the results of the lecture, the method of understanding and implementing algorithms for virtual reality perspective suitable for basic learning was studied. Based on practice, the research method of main theory was to create Vizrt contents specialized in 5G contents work in each sector and to implement graphic production in new areas from contents image. Through this study, we came to the conclusion of the basic training method through virtual reality content work based on Vizrt by practicing content creation according to the subject. It also proposes the effect of creating Vizrt content and the direction of building Vizrt basic training courses.

How Design Elements of a Social Q&A Site Influence New Users' Continuance Behavior: An Application of Logistic Regression and XGBoost Techniques (소셜 Q&A 사이트의 디자인 요소가 신규 사용자의 지속사용에 미치는 영향: 로지스틱 회귀분석과 XGBoost 기법의 적용)

  • Minhyung Kang
    • Knowledge Management Research
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    • v.24 no.2
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    • pp.161-183
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    • 2023
  • Social Q&A sites, where individuals freely ask and answer each other online, play an important role as a public knowledge repository. For their sustainable growth, social Q&A sites constantly need new askers and new answerers. However, previous studies have focused only on answerers, with little attention to new users or askers. This study examines the factors encouraging new users to continue using social Q&A sites based on motivational affordance theory and self-determination theory, and also investigates whether the factors differ depending on the types of users (i.e., new asker vs. new answerer). In addition, the moderating effect of prior experience with a member Q&A site was examined. Using logistic regression and XGBoost, we analyzed online activity data from 25,000 users in the Stack Exchange Network and found that design elements with motivational affordances had significant impacts on new users' continuance behavior. The experience of a member Q&A site negatively moderated the influence of the antecedents of continuance behavior. Interestingly, the influence of editing was not significant in the analysis of new users as a whole, but was significant in the separate analyses of askers (significantly negative) and answerers (significantly positive).