• 제목/요약/키워드: Functional matrix

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Neural circuit remodeling and structural plasticity in the cortex during chronic pain

  • Kim, Woojin;Kim, Sun Kwang
    • The Korean Journal of Physiology and Pharmacology
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    • 제20권1호
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    • pp.1-8
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    • 2016
  • Damage in the periphery or spinal cord induces maladaptive plastic changes along the somatosensory nervous system from the periphery to the cortex, often leading to chronic pain. Although the role of neural circuit remodeling and structural synaptic plasticity in the 'pain matrix' cortices in chronic pain has been thought as a secondary epiphenomenon to altered nociceptive signaling in the spinal cord, progress in whole brain imaging studies on human patients and animal models has suggested a possibility that plastic changes in cortical neural circuits may actively contribute to chronic pain symptoms. Furthermore, recent development in two-photon microscopy and fluorescence labeling techniques have enabled us to longitudinally trace the structural and functional changes in local circuits, single neurons and even individual synapses in the brain of living animals. These technical advances has started to reveal that cortical structural remodeling following tissue or nerve damage could rapidly occur within days, which are temporally correlated with functional plasticity of cortical circuits as well as the development and maintenance of chronic pain behavior, thereby modifying the previous concept that it takes much longer periods (e.g. months or years). In this review, we discuss the relation of neural circuit plasticity in the 'pain matrix' cortices, such as the anterior cingulate cortex, prefrontal cortex and primary somatosensory cortex, with chronic pain. We also introduce how to apply long-term in vivo two-photon imaging approaches for the study of pathophysiological mechanisms of chronic pain.

Electrical Properties of Organic/Inorganic Hybrid Composites for Insulation Materials

  • Kim, Sang-Cheol;Ok, Jeong-Bin;Aho, Myeong-Jin;Park, Do-Hyun;Lee, Gun-Joo
    • Transactions on Electrical and Electronic Materials
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    • 제3권1호
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    • pp.9-13
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    • 2002
  • In this work, the surface of inorganic fillers were modified with some functional groups such as stearic acid, aliphatic long chain, vinylsilane and aminosilane to control the interaction between inorganic fillers and polymer matrix. Ethylene-vinyl acetate copolymers (EVA) with various amount of vinyl-acetate and copolyether-ester elastomer were used as polymer matrix. The addition of inorganic fillers increases flame retardancy, but results in steep drop of electrical and mechanical properties, which may be caused by the defects in the interface between organic/inorganic hybrid composites. The hybrid composites are found to show better mechanical properties and higher volume resistivities as inorganic fillers are well dispersed and have good adhesion with polymer matrix. Also, the most effective type of functional group coated on fillers depends on the chemical structure of polymer.

제한된 구동기 용량을 갖는 시간지연 선형시스템의 $H_{\infty}$ 제어 ([ $H_{\infty}$ ] Control of Time-Delayed Linear Systems with Limited Actuator Capacities)

  • 이연규;김진훈
    • 전기학회논문지
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    • 제56권9호
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    • pp.1648-1654
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    • 2007
  • In this paper, we consider the design of $H_\infty$ high-gain state feedback control for time-delayed linear systems with limited actuator capacities. The high-gain control means that the control permits the predetermined degree of saturation. Based on new Lyapunov-Krasovskii functional, we derive a result in the form of matrix inequalities. The matrix inequalities are consisted of LMIs those confirm the positive definiteness of Lyapunov- Krasovskii functional, satisfaction of predetermined degree of saturation, reachable set and $L_2$ gain constraint. The result is dependent on the bound of time-delay and its rate, predetermined degree of saturation, actuator capacity, and the allowed size of disturbances. Finally, we give a numerical example to show the effectiveness and usefulness of our result.

시변 불확실성을 가지는 선형 시스템을 위한 반복 제어 시스템의 설계 (Design of Repetitive Control System for Linear Systems with Time-Varying Uncertainties)

  • 정명진;도태용
    • 제어로봇시스템학회논문지
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    • 제11권1호
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    • pp.13-18
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    • 2005
  • This paper considers a design problem of the repetitive control system for linear systems with time-varying norm bounded uncertainties. Using the Lyapunov functional for time-delay systems, a sufficient condition ensuring robust stability of the repetitive control system is derived in terms of an algebraic Riccati inequality (ARI) or a linear matrix inequality (LMI). Based on the derived condition, we show that the repetitive controller design problem can be reformulated as an optimization problem with an LMI constraint on the free parameter.

A FUNCTIONAL CENTRAL LIMIT THEOREM FOR MULTIVARIATE LINEAR PROCESS WITH POSITIVELY DEPENDENT RANDOM VECTORS

  • KO, MI-HWA;KIM, TAE-SUNG;KIM, HYUN-CHULL
    • 호남수학학술지
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    • 제27권2호
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    • pp.301-315
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    • 2005
  • Let $\{A_u,\;u=0,\;1,\;2,\;{\cdots}\}$ be a sequence of coefficient matrices such that ${\sum}_{u=0}^{\infty}{\parallel}A_u{\parallel}<{\infty}$ and ${\sum}_{u=0}^{\infty}\;A_u{\neq}O_{m{\times}m}$, where for any $m{\times}m(m{\geq}1)$, matrix $A=(a_{ij})$, ${\parallel}A{\parallel}={\sum}_{i=1}^m{\sum}_{j=1}^m{\mid}a_{ij}{\mid}$ and $O_{m{\times}m}$ denotes the $m{\times}m$ zero matrix. In this paper, a functional central limit theorem is derived for a stationary m-dimensional linear process ${\mathbb{X}}_t$ of the form ${\mathbb{X}_t}={\sum}_{u=0}^{\infty}A_u{\mathbb{Z}_{t-u}}$, where $\{\mathbb{Z}_t,\;t=0,\;{\pm}1,\;{\pm}2,\;{\cdots}\}$ is a stationary sequence of linearly positive quadrant dependent m-dimensional random vectors with $E({\mathbb{Z}_t})={{\mathbb{O}}$ and $E{\parallel}{\mathbb{Z}_t}{\parallel}^2<{\infty}$.

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Classification of Metro Station Areas Using Multi-Source Big Data: Case Studies in Beijing

  • Shuo Chen;Xiangyu Li
    • 국제초고층학회논문집
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    • 제12권1호
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    • pp.63-74
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    • 2023
  • Large-capacity public transportation systems, represented by urban metro lines, are the key to alleviating the significant increase in urbanization and motorization in China. But to improve the agglomeration effect of metro stations in a more accurate and targeted way requires scientific evaluation and classification of the surrounding areas of metro stations. As spatial and functional design are the core factors for urban renewal design, this study took Beijing as an example, using multi-source data to evaluate the morphology and functional composition surrounding areas of metro stations, and the Boston Consulting Group (BCG) matrix was used to classify and characterize each type of surrounding areas from morphological-functional dimensions. It shows a negative correlation of the mix-use index with the floor area ratio, and only about 20% of the areas achieve the ideal situation of high construction intensity with high mix-use diversity. Hoping to provide a reference for city managers and designers in dealing with the surrounding metro stations with different construction intensities in a more precise way.

Fluorescent and bioluminescent nanoprobes for in vitro and in vivo detection of matrix metalloproteinase activity

  • Lee, Hawon;Kim, Young-Pil
    • BMB Reports
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    • 제48권6호
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    • pp.313-318
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    • 2015
  • Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that degrade the extracellular matrix (ECM) and regulate the extracellular microenvironment. Despite the significant role that MMP activity plays in cell-cell and cell-ECM interactions, migration, and differentiation, analyses of MMPs in vitro and in vivo have relied upon their abundance using conventional immunoassays, rather than their enzymatic activities. To resolve this issue, diverse nanoprobes have emerged and proven useful as effective activity-based detection tools. Here, we review the recent advances in luminescent nanoprobes and their applications in in vitro diagnosis and in vivo imaging of MMP activity. Nanoprobes with the purpose of sensing MMP activity consist of recognition and detection units, which include MMP-specific substrates and luminescent (fluorescent or bioluminescent) nanoparticles, respectively. With further research into improvement of the optical performance, it is anticipated that luminescent nanoprobes will have great potential for the study of the functional roles of proteases in cancer biology and nanomedicine. [BMB Reports 2015; 48(6): 313-318]

Functional and aesthetic rehabilitation in posterior tooth with bulk-fill resin composite and occlusal matrix

  • Francisconi-dos-Rios, Luciana Favaro;Tavares, Johnny Alexandre Oliveira;Oliveira, Luanderson;Moreira, Jefferson Chaves;Nahsan, Flavia Pardo Salata
    • Restorative Dentistry and Endodontics
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    • 제45권1호
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    • pp.9.1-9.7
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    • 2020
  • The restorative procedure in posterior teeth involves clinical steps related to professional skill, especially when using the incremental technique, which may fail in the long term. A recent alternative is bulk-fill resins, which can reduce polymerization shrinkage, decreasing clinical problems such as marginal leakage, secondary caries, and fracture. This scientific study aims to report a clinical case using bulk-fill resin with an occlusal matrix. As determined in the treatment plan, an acrylic resin matrix was produced to establish an improved oral and aesthetic rehabilitation of the right mandibular first molar, which presented a carious lesion with dentin involvement. The occlusal matrix is a simple technique that maintains the original dental anatomy, showing satisfactory results regarding function and aesthetic rehabilitation.

A Functional Matrix Approach to Pedagogical Enrichment of the Dispositional Core of Future Specialists' Experience of Social Interaction

  • Kovalenko, E.V.;Gubarenko, I.V.;Kovalenko, V.I.
    • International Journal of Computer Science & Network Security
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    • 제22권11호
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    • pp.255-259
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    • 2022
  • The new social reality emerging amid the global rise of communication links and integration processes acutely emphasizes the problems of communication in large and small social systems. The method of their communication becomes one of the keys to ensuring global security. It has become the mission of humanitarian education to prepare the younger generations for life in a changing world with no image of the future and increasing uncertainty. In psychological and pedagogical research, there is a growing scientific interest in the problems of interaction of the individual with the social environment. The mental trace of a person's practice in society shapes the experience of social interaction, which constitutes simultaneously the source, tool, and condition for the emergence and development of personality. The study outlines the methodological foundations for the study of individual experiences of social interaction. A hypothesis about the productivity of the functional matrix method is tested. Materials for the training of specialists in the humanities include interdisciplinary approaches to the study and transformation of the experience of social interaction and systematic methodology for the study of complex objects. Fundamental to the study is the systematic-dialectical method, and the matrix method is employed as the instrumental-technological method. The paper presents the results of a multidisciplinary overview of scientific literature concerning the essential characteristics and functions of social interaction and the respective experience. The overview points to the fragmented nature of scientific understanding of the elements of experience outside its integrity and systemic properties. Based on the formula "personality interacts with the social environment", the study presents an algorithm for the application of a systematic methodology for the study of complex objects, which made it possible to identify the system parameters of experience at three levels of cognition and develop the reference structural and functional matrices for the didactic system of its pedagogical enrichment.

NEW RESULT CONCERNING MEAN SQUARE EXPONENTIAL STABILITY OF UNCERTAIN STOCHASTIC DELAYED HOPFIELD NEURAL NETWORKS

  • Bai, Chuanzhi
    • 대한수학회보
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    • 제48권4호
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    • pp.725-736
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    • 2011
  • By using the Lyapunov functional method, stochastic analysis, and LMI (linear matrix inequality) approach, the mean square exponential stability of an equilibrium solution of uncertain stochastic Hopfield neural networks with delayed is presented. The proposed result generalizes and improves previous work. An illustrative example is also given to demonstrate the effectiveness of the proposed result.