• Title/Summary/Keyword: dynamical systems

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TagPlus: A Retrieval System using Synonym Tag in Folksonomy (TagPlus: 폭소노미에서 동의어 태그를 이용한 검색 시스템)

  • Lee, Sun-Sook;Yong, Hwan-Seung
    • Journal of Digital Contents Society
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    • v.8 no.3
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    • pp.255-262
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    • 2007
  • Collaborative tagging describes the process by which many users add metadata in the form of keywords to shared content. Recently, collaborative tagging has grown in popularity on the web, on sites that allow users to tag bookmarks, photographs, videos and other content. In this paper, we analyze the structure and basic knowledge of collaborative tagging systems as well as their dynamical aspects. We also present a retrieval system, TagPlus, using synonym tag that is derived from WordNet database. Specifically, TagPlus, a synonym tag based system has users retrieve images from Flickr system. The proposed system show the images tagged by not only the tag that users input but also the synonyms that are synonyms with the tag.

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Nonlinear analysis of the effects on the brain waves of the stimulation on specific area of the sole of the foot (발바닥 특정 부위 자극이 뇌파에 미치는 효과에 대한 비선형 분석)

  • Oh, Yeong-seon;Oh, Min-seok;Song, Tae-won
    • Journal of Haehwa Medicine
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    • v.10 no.1
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    • pp.365-374
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    • 2001
  • The brain is one of the most complex systems in nature. Brain waves, or the "EEG", are electrical signals that can be recorded from the brain, either directly or through the scalp. The kind of brain wave recorded depends on the behavior of the animal, and is the visible evidence of the kind of neuronal (brain cell) processing necessary for that behavior. But, EEG had been considered as a virtually infinite-dimensional random signal. However, nonlinear dynamics light on dynamical aspects of the human EEG. The methods of nonlinear dynamics provide excellent tolls for the study of multi-variable, complex system such as EEG. In this study, 20 persons seperated in 2 groups were examined with EEG, one group stimulated on specific area of the sole of the foot with footbed inside the shoes. This experiment resulted in at the group stimulated on specific area of the sole of the foot correlation dimension of P4 and O1 channels increased significantly. Therefore. we obserbed that stimulation on specific area of the body had a constant effections on the specific channels.

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Magnetic Properties of Cr-doped LiNbO3 by Using the Projection Operator Technique

  • Park, Jung-Il;Lee, Hyeong-Rag;Lee, Haeng-Ki
    • Journal of Magnetics
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    • v.16 no.2
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    • pp.108-113
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    • 2011
  • The electron spin resonance lineshape (ESRLS) function for the electron spin resonance linewidth (ESRLW) of $Cr^{3+}$ (S = 3/2) in ferroelectric lithium niobate single crystals doped with 0.05 wt% of Cr, is obtained by using the projection operator technique (POT), developed by Argyres and Sigel. The ESRLS function is calculated to be axially symmetric about the c - axis and analyzed by using the spin Hamiltonian $H_{SP}={\mu}_B(B{\cdot}{^\leftrightarrow_{g}}{\cdot}S)+S{\cdot}{^\leftrightarrow_{D}}{\cdot}S$ with the parameters g = 1.972 and D = $0.395\;cm^{-1}$. In the ca plane, the linewidths show a strong angular dependence, whereas in the ab plane, they are independent of the angle. This result implies that the resonance center has an axial symmetry along the c - axis. Further, from the temperature dependence of the linewidths that is shown, it can be seen that the linewidths increase as the temperature increases, at a frequency of v = 9.27GHz. This result implies that the scattering effect increases with increasing temperature. Thus, the POT is considered to be more convenient to explain the scattering mechanism as in the case of other optical resonant systems.

A Systems Approach to Immune Response for Cancer Treatment (암 치료를 위한 면역반응의 체계적인 연구)

  • ;Ronald R.Mohier
    • Journal of Biomedical Engineering Research
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    • v.13 no.3
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    • pp.181-188
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    • 1992
  • This paper provides an overview of system analysis of immunology. The theoretical research in this area is aimed at an understanding of the precise manner by which the immune system controls Infec pious diseases, cancer, and AIDS. This can provide a systematic plan for immunological experimentation by means of an integrated program of immune system analysis, mathematical modeling and computer simulation. Biochemical reactions and cellular fission are naturally modeled as nonlinear dynamical processes to synthesize the human immune system! as well as the complete organism it is intended to protect. A foundation for the control of tumors is presented, based upon the formulation of a realistic, knowledge based mathematical model of the interaction between tumor cells and the immune system. Ordinary bilinear differential equations which are coupled by such nonlinear term as saturation are derived from the basic physical phenomena of cellular and molecular conservation. The parametric control variables relevant to the latest experimental data are also considered. The model consists of 12 states, each composed of first-order, nonlinear differential equations based on cellular kinetics and each of which can be modeled bilinearly. Finally, tumor control as an application of immunotherapy is analyzed from the basis established.

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Colourings and the Alexander Polynomial

  • Camacho, Luis;Dionisio, Francisco Miguel;Picken, Roger
    • Kyungpook Mathematical Journal
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    • v.56 no.3
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    • pp.1017-1045
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    • 2016
  • Using a combination of calculational and theoretical approaches, we establish results that relate two knot invariants, the Alexander polynomial, and the number of quandle colourings using any finite linear Alexander quandle. Given such a quandle, specified by two coprime integers n and m, the number of colourings of a knot diagram is given by counting the solutions of a matrix equation of the form AX = 0 mod n, where A is the m-dependent colouring matrix. We devised an algorithm to reduce A to echelon form, and applied this to the colouring matrices for all prime knots with up to 10 crossings, finding just three distinct reduced types. For two of these types, both upper triangular, we found general formulae for the number of colourings. This enables us to prove that in some cases the number of such quandle colourings cannot distinguish knots with the same Alexander polynomial, whilst in other cases knots with the same Alexander polynomial can be distinguished by colourings with a specific quandle. When two knots have different Alexander polynomials, and their reduced colouring matrices are upper triangular, we find a specific quandle for which we prove that it distinguishes them by colourings.

Service Path Guidance System is based on speed Information (속도 정보를 기반으로 한 차량 경로 제공 시스템에 대한 연구)

  • Kim, Tae-Min;Kim, Jin-Ho;Lee, Jong-Su
    • Proceedings of the KIEE Conference
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    • 2007.10a
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    • pp.361-362
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    • 2007
  • This paper presents the Traffic information system that based on an embedded WinCE board which has GPS and HSDPA. This system is able to overcome the limit of area using the Internet service which other systems can't provide. When the embedded board receives data about the geometric and vehicle speed information, it transmits to the server via HSDPA/the Internet. The server receives and processes it for the path services. And also we present the path guidance algorithm which is based on the speed information. These algorithm responses to the dynamical traffic condition through updating traffic information. Especially, we suggest a Traffic Status Variable in each branch which represents each road's traffic status. This Traffic Status Variable contains speed, road grade; we separate the road three groups as speed limitation; and past speed data - for example, week day rush hour of each road. In addition, the data of cross about left-turn or right-turn can update. Those elements is consisted Traffic Status Variable.

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Dynamic Characteristic Analysis of Water Jet Loom Driving System (워터제트직기 구동시스템의 동특성 해석)

  • Kim, Sang-Yoon;Park, Dae-Kyu;Chun, Du-Hwan;Park, Myung-Kyu
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.21 no.5
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    • pp.459-464
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    • 2008
  • While high speed / precision investigating for maximization of Textile Machinery business is requesting a machine which has highly endurance, stability and reliance abilities following customer request. In this research, load volume that gives influence on loom is measured and analyzed for water jet loom in real operation time to driving system adhered torque sensor to each a module. As well, measurement and analysis technology are developed about torque and vibration of driving systems for textile machinery by comparing dynamical analysis of water jet loom with gained result, basic materials about development of high value added textile machinery which has endurance and stability are presented.

Dissipation Inequality of LTI System Based on Pencil Model

  • Shibasato, Koki;Shiotsuki, Tetsuo;Kawaji, Shigeyasu
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.135-140
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    • 1998
  • The concept of dissipativity and passivity are of interest to us from a theoretical as well as a practical point of view. It is well known that the Riccati equation is derived from the dissipation inequality which expresses the fact that the system is dissipative; the energy stored inside the system doesn't exceed the amount of supply which flows into the system. The pencil model is regarded as a representation based on behavioral approach introduced by J.C. Willems. It has first order in the internal variable and zeroth order in the external variable. In general, any matrix pencil is transformed into a canonical form which is consist of several kind of sub-pencils, One of them has row full rank for $^\forall S\;\in\;\mathds{C}\;\bigcup{\infty}$, we call it under-determined mode of the model. In our opinion, most important properties of dynamical system lay in the mode. According to the properties of canonical form for pencil, it is shown that the storage function which characterizes the dissipativity of the system can be written as a LMI for the under-determined mode, if the system doesn't include impulse mode.

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Adaptive Fuzzy Observer without SPR Condition for Uncertain Nonlinear Systems (불확실한 비선형 계통에 대한 SPR 조건이 필요 없는 적응 퍼지 관측기)

  • Park, Jang-Hyun;Kim, Seong-Hwan
    • Journal of IKEEE
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    • v.7 no.2 s.13
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    • pp.156-165
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    • 2003
  • This paper describes the design of a robust adaptive fuzzy observer for uncertain nonlinear dynamical system. We propose a new method in which no strictly positive real (SPR) condition is needed. No a priori knowledge of an upper bound on the lumped uncertainty is required. The Lyapunov synthesis approach is used to guarantee a semi-global uniform ultimate boundedness property of the state observation error, as well as of all other signals in the closed-loop system. The theoretical results are illustrated through a simulation example of a mass-spring-damper system.

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A Variational Numerical Method of Linear Elasticity through the Extended Framework of Hamilton's Principle (확장 해밀턴 이론에 근거한 선형탄성시스템의 변분동적수치해석법)

  • Kim, Jinkyu
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.27 no.1
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    • pp.37-43
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    • 2014
  • The extended framework of Hamilton's principle provides a new rigorous weak variational formalism for a broad range of initial boundary value problems in mathematical physics and mechanics in terms of mixed formulation. Based upon such framework, a new variational numerical method of linear elasticity is provided for the classical single-degree-of-freedom dynamical systems. For the undamped system, the algorithm is symplectic with respect to the time step. For the damped system, it is shown to be accurate with good convergence characteristics.