• 제목/요약/키워드: term functions

검색결과 800건 처리시간 0.03초

Analysis of Postural Stability During Continuous External Perturbations

  • Shin, Youngkyun;Park, Gu-Bum
    • 조명전기설비학회논문지
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    • 제27권8호
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    • pp.21-29
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    • 2013
  • The functional behaviors of human standing postural control were investigated when they were exposed to long-term horizontal vibration in the sagittal plane. For complexity of human postural control, a useful alternative method that has been based on a black-box approach was taken; that is, where the feedback mechanism was lumped into a single element. A motor-driven support platform was designed as a source of vibration. The AC Servo-controlled motors produced continuous anterior/posterior (AP) motion. The data were analyzed both in the time and frequency domain. The cross-correlation and coherency functions were estimated. Subjects behaved as a non-rigid pendulum with a mass and a spring throughout the whole period of the platform motion, as consistent with the plan chosen for this study.

One-dimensional consolidation with asymmetrical exponential drainage boundary

  • Mei, Guo-Xiong;Lok, Thomas M.H.;Xia, Jun;Wu, Sheng Shen
    • Geomechanics and Engineering
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    • 제6권1호
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    • pp.47-63
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    • 2014
  • In this paper, asymmetric drainage boundaries modeled by exponential functions which can simulate intermediate drainage from pervious to impervious boundary is proposed for the one-dimensional consolidation problem, and the solution for the new boundary conditions was derived. The new boundary conditions satisfy the initial and the steady state conditions, and the solution for the new boundary conditions can be degraded to the conventional solution by Terzaghi. Convergence study on the infinite series solution showed that only one term in the series is needed to meet the precision requirement for larger degree of consolidation, and that more terms in the series for smaller degree of consolidation. Comparisons between the present solution with those by Terzaghi and Gray are also provided.

구조물 주변의 Stokes 흐름에 대한 적응적 유한요소 해석을 위한 변절점 요소 (Variable-Node Element for Adaptive Finite Element Analysis of Stokes Flow around Structure)

  • 최창근;유원진;정근영
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1996년도 가을 학술발표회 논문집
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    • pp.168-175
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    • 1996
  • This paper deals with the variable-node element for fluid flow and the adaptive h-version mesh refinement algorithm. The transient element has been formulated by the Galerkin approach in which the pressure term is replaced with the penalty function. The present element having variable mid-side node and is suitable for constructing a locally refined mesh avoiding the use of the highly distorted elements. A modified Gauss quadrature is needed to integrate the element matrices to solve the trouble associated with the discontinuity of derivatives of shape functions. Several numerical examples show that the proposed element can be effectively used in the h-version adapt ive mesh refinement

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지역사란 무엇인가\ulcorner (What is Natural History\ulcorner)

  • Choe, Jae Chun
    • The Korean Journal of Ecology
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    • 제18권4호
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    • pp.525-531
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    • 1995
  • The Korean government has recently announced its plan to establish the first National Museum of Natural History. However, the Korean word for natural history, jayonsa, is not a very familiar term to some academics as well as the general public. This article discusses the definition and history of natural history, describes the functions of natural history meseums, and makes suggestions to the establishment of our National Museum. Modern natural history is no longer an art of ‘stamp collecting’. It is a comprehensive scientific endeavor pursuing to enlighten the history of the planet Earth and the diversity of natural objects it contains. Natural history museum must have two museums within the museum: the outer museum for exhibition and general public education and the inner museum for research and specialist education. I hope that our National Museum of Natural History will be a place where we all get to know about Nature and thus to love her.

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총정맥영양(TPN)과 관련된 미량원소의 결핍 (Trace Element Deficiency in Children Receiving Total Parenteral Nutrition (TPN))

  • 이정화
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제11권sup1호
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    • pp.117-126
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    • 2008
  • Trace elements compose a very small portion of the body, however they have a variety of essential functions. Various diseases are caused by trace element deficiencies, and sometimes they can be fatal. Long-term TPN is a risk factor of trace element deficiency, and trace elements need to be checked regularly while receiving TPN. It is important to provide sufficient requirements of trace elements regarding the clinical features and the problems of trace element excess or deficiency. Moreover extensive studies to establish the efficiency of examining human hair and nails, recent method to determine the trace elements, are required.

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Fragile X Mental Retardation Protein in Learning-Related Synaptic Plasticity

  • Mercaldo, Valentina;Descalzi, Giannina;Zhuo, Min
    • Molecules and Cells
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    • 제28권6호
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    • pp.501-507
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    • 2009
  • Fragile X syndrome (FXS) is caused by a lack of the fragile X mental retardation protein (FMRP) due to silencing of the Fmr1 gene. As an RNA binding protein, FMRP is thought to contribute to synaptic plasticity by regulating plasticity-related protein synthesis and other signaling pathways. Previous studies have mostly focused on the roles of FMRP within the hippocampus - a key structure for spatial memory. However, recent studies indicate that FMRP may have a more general contribution to brain functions, including synaptic plasticity and modulation within the prefrontal cortex. In this brief review, we will focus on recent studies reported in the prefrontal cortex, including the anterior cingulate cortex (ACC). We hypothesize that alterations in ACC-related plasticity and synaptic modulation may contribute to various forms of cognitive deficits associated with FXS.

RIMS "지능형 BOM" 구축과 활용에 관한 연구 (Research on construction and application of RIMS with "intelligent BOM")

  • 박수중;이도선;최광석;손영진;김명규
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1499-1504
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    • 2007
  • This dissertation explains the construction of the expert system which can manage diagnosis and administration of trouble using circuit diagram through connection between BOM and ability term and makes up for problem which have designed RIMS with name of parts. Also this dissertation explains that existing BOM has no regard organic relation of parts and functional and systematic appearance of the flow of electricity or air. Construction of expert system and "Be enlivened BOM" with flowing electricity and air can solve problems about overlapping parts carrying out other functions with the same name of parts following to simple and physical BOM management and having mistaken trouble of the end caused by basis for trouble of the end.

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OPTIMALITY AND DUALITY IN NONDIFFERENTIABLE MULTIOBJECTIVE FRACTIONAL PROGRAMMING USING α-UNIVEXITY

  • Gupta, Rekha;Srivastava, Manjari
    • Journal of applied mathematics & informatics
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    • 제32권3_4호
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    • pp.359-375
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    • 2014
  • In this paper, a multiobjective nondifferentiable fractional programming problem (MFP) is considered where the objective function contains a term involving the support function of a compact convex set. A vector valued (generalized) ${\alpha}$-univex function is defined to extend the concept of a real valued (generalized) ${\alpha}$-univex function. Using these functions, sufficient optimality criteria are obtained for a feasible solution of (MFP) to be an efficient or weakly efficient solution of (MFP). Duality results are obtained for a Mond-Weir type dual under (generalized) ${\alpha}$-univexity assumptions.

The Interaction Potential Functions in an Electrolyte Protein Solution

  • Jee, Nam-Yong;Kim, Jae-Jun
    • Macromolecular Research
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    • 제14권6호
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    • pp.654-658
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    • 2006
  • Recent developments in equations of state for molecular fluids have demonstrated the feasibility of using the hard-sphere equation to describe the effects of repulsive forces in simple fluids. By including a suitable term for attractive forces, most conveniently a uniform background potential, the properties of bio-macromolecular interaction can be roughly calculated. However, the choice of the potential used in perturbed hard-sphere chain (PHSC) theory for describing the attractions between macromolecules is rather complicated. For hard-sphere chains, the prediction accuracy from each model strongly depends on the choice of potential function.

Compensation of a Squint Free Phased Array Antenna System using Artificial Neural Networks

  • Kim, Young-Ki;Jeon, Do-Hong;Park, Chiyeon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제4권2호
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    • pp.182-186
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    • 2004
  • This paper describes an advanced compensation for non-linear functions designed to remove steering aberrations from phased array antennas. This system alters the steering command applied to the antenna in a way that the appropriate angle commands are given to the array steering software for the antenna to point to the desired position instead of squinting. Artificial neural networks are used to develop the inverse function necessary to correct the aberration. Also a straightforward antenna steering function is implemented with neural networks for the 9-term polynomials of forward steering function. In all cases the aberration is removed resulting in small RMS angular errors across the operational angle space when the actual antenna position is compared with the desired position. The use of neural network model provides a method of producing a non-linear system that can correct antenna performance and demonstrates the feasibility of generating an inverse steering algorithm.