• Title/Summary/Keyword: systems-theory

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A Study on Control of Posture and Balance (자세와 균형 조절에 관한 연구)

  • Jeong Dong-Hoon;Kwon Hyuk-Cheol
    • The Journal of Korean Physical Therapy
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    • v.11 no.3
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    • pp.23-36
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    • 1999
  • The very definitions of posture and balance have changed, as has our understanding of the underlying neural mechanisms, In rehabilitation science, there awe at least two different conceptual theories to describe the neural control of posture and balance : the reflex/hierarchical theory and system theory. A reflex/hierarchical theory suggests the posture and balance result from hierarchically organized reflex responses triggered by independent sensory systems. The systems approach suggests that action emerges from an interaction of the individual with the task and environment. That is to say, the systems approach implies that the ability to control our body's position in space emerges from a complex interaction of musculoskeletal and neural systems, collectively referred to as the postural control system. The specific organization of postural systems determined both by the functional task and the environment in which it is being performed, The postural control system is divided into three basic functional components for assessment : 1) musculoskeletal components, 2) motor coordination components, and 3) sensory organization components. It is proposed that a systemic functional understanding of human balance is critical to effective programs for balance rehabilitation. Thus, this article briefly reviews the basic functional components to consider in designing treatment plan and for the benefit of the balance assessment.

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Formation of Interdependence in Selecting Game

  • Iizuka, Hiroyuki;Yamamoto, Masahito;Kawamura, Hidenori;Suzuki, Keiji;Ohuchi, Azuma
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.80-83
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    • 2000
  • Decision-makers in ecological system and social system have complex interactions and relations. Such interactions and relations are not predefined but dynamically constructed. We consider what relation-s are constructed or destroyed and how the relations change. Therefore, we focus on the formation and collapse of relations as one of the emergent phenomena of social or ecological complex phenomena. Game theory is the best way of analyzing phenomena in terms of interactions. However, it is difficult to analyze the dynamical system by game theory. Consequently, we propose Selecting Game with agents as players based on game theory. In this model, the relations among agents are not predefined but constructed by selecting subgames. As a result, we confirmed that the entire relation among agents is constructed by the agents' changing partial relations and that the relations dynamically change.

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The Impacts of Media Richness, Media Usefulness, and Media Experience on the Leaner's Satisfaction with e-Learning Systems (이러닝시스템의 매체풍부성, 매체유용성, 매체경험이 학습자 만족에 미치는 영향)

  • Choi, Su-Jeong;Kang, Kyung-Jun;Ko, Il-Sang
    • Journal of Information Technology Applications and Management
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    • v.14 no.2
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    • pp.27-47
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    • 2007
  • In an effort to apply IT to practices of learning, universities are trying to implement e-Learning systems and expanding the extent of their usage. Nowadays, e-Learning systems are not only used for conducting web-based distance learning, but also used for supporting traditional classes education by encouraging communication and information sharing between instructors and learners or among the learners. There is relatively lack of studies on the exploitation of e-Learning systems in the traditional classes, in comparison with a distance education. Specifically, howe-Learning systems could support the traditional class and/or which benefits e-Learning systems could offer in the classes are among the important issues. In this study, we suggest that e-Learning systems would be the rich media to communicate and exchange information among people who participate in a class. We derive key variables like media richness and media experience from Media Richness Theory and from Channel Expansion Theory. Moreover, Media usefulness and Satisfaction of a learner with e-Learning system is drawn from the literature on IS success. We examine the effects of perceived media richness, media usefulness, and media experience on leaner's satisfaction with e-Learning systems. In addition, we also investigate learner's media usefulness perception which is positively related to media richness and media experience. Finally, learner's experience with e-Learning systems affects perceived media richness. Based on the results of an empirical test. we first suggest that perceived media richness with e-Learning systems contributes to increase media usefulness and satisfaction of a learner. Second, media experience is an important predictor of media richness and media usefulness perception. Consequently, the result can support Channel Expansion Theory. Finally, media usefulness perception affects learner's satisfaction with e-Learning systems.

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A Study of Business Information Management of Ethical Analysis (기업정보관리의 윤리적 분석에 관한 연구)

  • Jang Ik-Seon
    • Management & Information Systems Review
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    • v.1
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    • pp.167-191
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    • 1997
  • 1. Today mass communication informs us of the unethical behaviors of business almost everyday and the social interest about them including individuals implicated in loss and gain grows larger. It is the real aspect that business manager and scholars do not cope with the situation. 2. Five business ethical scales as justice theory, relativism, egoism, utilitarianism, deontological theory and information ethics were applied to this thesis. 3. Hypothesis : There will he a difference in the response on five ethical scales and the recognition degree of information ethics with consumers. 4. The response on five ethical scales with the sex of consumers showed a significant difference but that with the age showed a little difference that with the academic career showed a significant difference in justice theory, relativism, utilitarianism and deontological theory 5. The recognition degree of information ethics with the age and academic career of consumers showed a significant difference and the hypothesis was accepted, but that with the sex showed a little difference.

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SOME RESULTS ON COMPLEX DIFFERENTIAL-DIFFERENCE ANALOGUE OF BRÜCK CONJECTURE

  • Chen, Min Feng;Gao, Zong Sheng
    • Communications of the Korean Mathematical Society
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    • v.32 no.2
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    • pp.361-373
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    • 2017
  • In this paper, we utilize the Nevanlinna theory and uniqueness theory of meromorphic function to investigate the differential-difference analogue of $Br{\ddot{u}}ck$ conjecture. In other words, we consider ${\Delta}_{\eta}f(z)=f(z+{\eta})-f(z)$ and f'(z) share one value or one small function, and then obtain the precise expression of transcendental entire function f(z) under certain conditions, where ${\eta}{\in}{\mathbb{C}}{\backslash}\{0\}$ is a constant such that $f(z+{\eta})-f(z){\not\equiv}0$.

Application of Eringen's nonlocal elasticity theory for vibration analysis of rotating functionally graded nanobeams

  • Ebrahimi, Farzad;Shafiei, Navvab
    • Smart Structures and Systems
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    • v.17 no.5
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    • pp.837-857
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    • 2016
  • In the present study, for first time the size dependent vibration behavior of a rotating functionally graded (FG) Timoshenko nanobeam based on Eringen's nonlocal theory is investigated. It is assumed that the physical and mechanical properties of the FG nanobeam are varying along the thickness based on a power law equation. The governing equations are determined using Hamilton's principle and the generalized differential quadrature method (GDQM) is used to obtain the results for cantilever boundary conditions. The accuracy and validity of the results are shown through several numerical examples. In order to display the influence of size effect on first three natural frequencies due to change of some important nanobeam parameters such as material length scale, angular velocity and gradient index of FG material, several diagrams and tables are presented. The results of this article can be used in designing and optimizing elastic and rotary type nano-electro-mechanical systems (NEMS) like nano-motors and nano-robots including rotating parts.

The Design of Variable Structure Controller for the Systems Having the First Order Dynamic (일차 Dynamic을 갖는 계통에 대한 가변구조 제어기의 설계)

  • 박귀태;최종경;김동식
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.4
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    • pp.392-399
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    • 1992
  • This paper will describe the application of variable structure control theory to the first order dynamic system and verify its robustness. The study on the first order dynamic system control which has been essential part for the control of servo motor (AC,DC) systems has been excluded in the study of variable structure control system(VSCS) because this first order system was not applicable to the previous variable structure control theory. So, for the robustness control of first order dynamic system with variable structure control theory, we propose modified switching function synthesis which guarantees the advantages of conventional VSCS and removes reaching phase which is regarded as shortcomings in VSCS. And we demonstrate the practical potential of implementation about this theory by simulation results of AC motor variable speed control.

The Effect of Cognitive Absorption on the Individual Intention of Technology Acceptance: An Empirical Study on the MP3 Player (인지적 몰입이 개인의 기술 수용에 미치는 영향: MP3 플레이어에 대한 실증 연구)

  • Kim, Bo-Youn;Lee, Sang-Gun;Kang, Min-Cheol
    • Asia pacific journal of information systems
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    • v.16 no.1
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    • pp.45-69
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    • 2006
  • Technology Acceptance Model (TAM) has been widely used to predict user's behavior to accept the technology. Prior researches have been mainly focused on innovation constructs such as perceived usefulness and perceived ease of use. However, very little research has been conducted to understand individual mental beliefs in technology acceptance and imitation influence. This study integrates Technology Acceptance Model (TAM), Flow Theory (FT) and Diffusion of Innovation Theory (DIT). This paper indicates that imitation context, cognitive absorption (CA) based Flow theory and innovation context are the three important factors influencing user acceptance of information technologies. The proposed model has been tested among 232 users of MP3 players. Results showed that innovation context and cognitive absorption have positive influences on intention to use technology. Not all factors of the imitation context have direct effect on intention to use. However, we found that imitation context has positive influence on intention to use technology through cognitive absorption.

Trajectory Planning of Multi Agent Robots for Robot Soccer Using Complex Potential (복소 포텐셜을 이용한 로봇 축구용 다개체 로봇의 경로 계획)

  • Lee, Kyunghee;Kim, Donghan;Rew, Keun-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.12
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    • pp.1073-1078
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    • 2012
  • This paper deals with the trajectory planning of multi agent robots using complex potential theory for robot soccer. The complex potential theory is introduced, then the circle theorem is used to avoid obstacles, and the vortex pair is used to make precise kicking direction of robot. Various situations of robot soccer are simulated and the effect of vortex strength and the speed of robots are discussed and the better way to avoid obstacles and to kick the precise direction is found. The feasibilities of complex potential theory to apply for the multi agent robots are successful.

Features Extraction of Remote Sensed Multispectral Image Data Using Rough Sets Theory (Rough 집합 이론을 이용한 원격 탐사 다중 분광 이미지 데이터의 특징 추출)

  • 원성현;정환묵
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.3
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    • pp.16-25
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    • 1998
  • In this paper, we propose features extraction method using Rough sets theory for efficient data classifications in hyperspectral environment. First, analyze the properties of multispectral image data, then select the most efficient bands using discemibility of Rough sets theory based on analysis results. The proposed method is applied Landsat TM image data, from this, we verify the equivalence of traditional bands selection method by band features and bands selection method using Rough sets theory that pmposed in this paper. Finally, we present theoretical basis to features extraction in hyperspectral environment.

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