• Title/Summary/Keyword: Potential Functions

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Complexity Reduction of Blind Algorithms based on Cross-Information Potential and Delta Functions (상호 정보 포텐셜과 델타함수를 이용한 블라인드 알고리듬의 복잡도 개선)

  • Kim, Namyong
    • Journal of Internet Computing and Services
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    • v.15 no.3
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    • pp.71-77
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    • 2014
  • The equalization algorithm based on the cross-information potential concept and Dirac-delta functions (CIPD) has outstanding ISI elimination performance even under impulsive noise environments. The main drawback of the CIPD algorithm is a heavy computational burden caused by the use of a block processing method for its weight update process. In this paper, for the purpose of reducing the computational complexity, a new method of the gradient calculation is proposed that can replace the double summation with a single summation for the weight update of the CIPD algorithm. In the simulation results, the proposed method produces the same gradient learning curves as the CIPD algorithm. Even under strong impulsive noise, the proposed method yields the same results while having significantly reduced computational complexity regardless of the number of block data, to which that of the e conventional algorithm is proportional.

Researches on the Potential Rises on the Neutral Line in Three Phase, Four-Wire Distribution Line Systems (공통중성선 3상4선식 배전선로의 중성선 전위상승에 관한 연구)

  • Park, Young-Moon
    • 전기의세계
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    • v.18 no.6
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    • pp.23-32
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    • 1969
  • The thesis has derived the formulas and computational algorithms useful for predicting and constraining the potential rises on the neutral line in 3-phase, 4-wire distribution line systems in the case of contact faults and single-line grounding faults. In addition it has suggested economically optimal designing conditions herewith of the distribution line systems in conduction with the potential restraining cost functions.

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On the Size of Quantum Dots with Bound Hydrogenic Impurity States

  • Sun, Ho-Sung
    • Bulletin of the Korean Chemical Society
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    • v.30 no.2
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    • pp.315-318
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    • 2009
  • Some particular bound state energies of an electron, under Coulomb potential field, confined in a two-dimensional circle and a three-dimensional sphere are analytically derived. The derivation shows that the electron cannot be bound in a negative energy state when the circle (or sphere) is smaller than a certain critical size. The critical size dependency on the strength of Coulomb potential and the angular momentum of the electron is also analytically derived. This system mimics quantum dots. Therefore the derivation provides new information on a minimum critical size of quantum dots with hydrogenic impurity.

Effects of Hormone Replacement Therapy on Motor Functions in Postmenopausal Women: A Systematic Reviews and Meta-Analysis (호르몬 대체 요법 제공이 폐경기 이후 여성들의 운동기능에 미치는 영향: 체계적 문헌고찰 및 메타분석 연구)

  • Lee, Hanall;Park, Young-Min;Kang, Nyeonju
    • Korean Journal of Applied Biomechanics
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    • v.32 no.2
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    • pp.56-68
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    • 2022
  • Objective: The purpose of this systematic review and meta-analysis was to investigate potential effects of HRT (hormone replacement therapy) on motor functions in postmenopausal women. Method: In this meta-analysis, 19 studies that examined changes in motor functions between postmenopausal women with and without HRT intervention were qualified. We additionally conducted moderator variable analyses including: (1) motor function type, (2) hormone type, and (3) duration of HRT intervention. Results: The random effects model showed no significant overall effects (SMD = 0.199; SE = 0.115; 95% CI = -0.026~0.425; Z = 1.730; p = 0.084; I2 = 93.258%). Additional three moderator variable analyses revealed no significant effect sizes indicating that specific HRT protocols did not improve different motor functions in postmenopausal women. Conclusion: These meta-analytic findings suggest that HRT had no positive effects on motor functions in postmenopausal women.

A Unified Analytical Surface Potential Model for SOI MOSFETs (SOI MOSFET의 모든 동작영역을 통합한 해석적 표면전위 모델)

  • 유윤섭
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.2
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    • pp.9-15
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    • 2004
  • We present a new unified analytical front surface potential model, which can accurately describe the transitions between the partially-depleted (PD) and the fully-depleted (FD) regimes with an analytical expression for the critical voltage V$_{c}$ delineating the PD and the FD region. It is valid in all regions of operation (from the sub -threshold to the strong inversion) and has the shorter calculation time than the iterative procedure approach. A charge sheet model based on the above explicit surface potential formulation is used to derive a single formula for the drain current valid in all regions of operation. Most of the secondary effects can be easily included in the charge sheet model and the model accurately reproduces various numerical and experimental results. No discontinuity in the derivative of the surface potential is found even though three types of smoothing functions are used. More importantly, the newly introduced parameters used in the smoothing functions do not strongly depend on the process parameter.

Assessment of Potential Interference between Grounding Electrodes Using ETM Method (ETM 기법을 이용한 접지전극의 전위간섭 평가)

  • Gil, Hyoung-Jun;Kim, Dong-Ook;Kim, Dong-Woo;Lee, Ki-Yeon;Choi, Chung-Seog
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2007.11a
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    • pp.333-336
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    • 2007
  • This paper deals with assessment of potential interference between grounding electrodes using ETM(Electrolytic Tank Modeling) method. When a test current flowed through grounding electrode, potential rise was measured and analyzed using an electrolytic tank in real time. In order to analyze the potential interference between grounding electrodes, ETM method was studies. Potential interference between isolated grounding electrodes was evaluated as functions of the separation distance between grounding electrodes and the configuration of grounding electrode to be induced. It was found that the separation distance between grounding electrodes in reducing the potential interference was a major factor.

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Local Structure Invariant Potential for InxGa1-xAs Semiconductor Alloys

  • Sim, Eun-Ji;Han, Min-Woo;Beckers, Joost;De Leeuw, Simon
    • Bulletin of the Korean Chemical Society
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    • v.30 no.4
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    • pp.857-862
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    • 2009
  • We model lattice-mismatched group III-V semiconductor $In_{x}Ga_{1-x}$ alloys with the three-parameter anharmonic Kirkwood-Keating potential, which includes realistic distortion effect by introducing anharmonicity. Although the potential parameters were determined based on optical properties of the binary parent alloys InAs and GaAs, simulated dielectric functions, reflectance, and Raman spectra of alloys agree excellently with experimental data for any arbitrary atomic composition. For a wide range of atomic composition, InAs- and GaAs-bond retain their respective properties of binary parent crystals despite lattice and charge mismatch. It implies that use of the anharmonic Kirkwood-Keating potential may provide an optimal model system to investigate diverse and unique optical properties of quantum dot heterostructures by circumventing potential parameter searches for particular local structures.

The Effects of Polygonum Cuspidatum on the Skin Functions (호장근추출물이 피부질환 및 피부미용에 미치는 영향)

  • Jung, Hyun-A;Roh, Seok-Seon;Oh, Min-Suck
    • Journal of Korean Medicine Rehabilitation
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    • v.19 no.1
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    • pp.73-89
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    • 2009
  • Objectives : This study was carried out to investigate the effects of Polygonum cuspidatum extract on several skin functions including inflammation and wrinkle formation. Methods : To investigate in vitro anti-oxidant activity assay, ethanol extracts of medicinal plants tested by DPPH method. In the next experiment, to investigate anti-inflammatory test, the RAW 264.7 macrophage cells was cultured using DMEM including the 10% FBS. To study anti-allergic effect, we blended cultured Human Mast Cells(HMC-1), and then observe $TNF-{\alpha}$, IL-8 by ELISA Results : Polygonum Cuspidatum extract has the effects of anti-inflammation and anti-allergy, which may be due to its inhibitory potential on the macrophage activation. Furthermore, Polygonum Cuspidatum extract has the anti-wrinkle effects through the inhibitory potential on the collagnease, elastase and gelatinase activities. Conclusions : The above results suggest that Polygonum Cuspidatum extract could be applicable for improvement of several skin functions.

Application of shear deformation theory for two dimensional electro-elastic analysis of a FGP cylinder

  • Arefi, M.;Rahimi, G.H.
    • Smart Structures and Systems
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    • v.13 no.1
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    • pp.1-24
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    • 2014
  • The present study deals with two dimensional electro-elastic analysis of a functionally graded piezoelectric (FGP) cylinder under internal pressure. Energy method and first order shear deformation theory (FSDT) are employed for this purpose. All mechanical and electrical properties except Poisson ratio are considered as a power function along the radial direction. The cylinder is subjected to uniform internal pressure. By supposing two dimensional displacement and electric potential fields along the radial and axial direction, the governing differential equations can be derived in terms of unknown electrical and mechanical functions. Homogeneous solution can be obtained by imposing the appropriate mechanical and electrical boundary conditions. This proposed solution has capability to solve the cylinder structure with arbitrary boundary conditions. The previous solutions have been proposed for the problem with simple boundary conditions (simply supported cylinder) by using the routine functions such as trigonometric functions. The axial distribution of the axial displacement, radial displacement and electric potential of the cylinder can be presented as the important results of this paper for various non homogeneous indexes. This paper evaluates the effect of a local support on the distribution of mechanical and electrical components. This investigation indicates that a support has important influence on the distribution of mechanical and electrical components rather than a cylinder with ignoring the effect of the supports. Obtained results using present method at regions that are adequate far from two ends of the cylinder can be compared with previous results (plane elasticity and one dimensional first order shear deformation theories).

Numerical and random simulation procedure for preliminary local site characterization and site factor assessing

  • Beneldjouzi, Mohamed;Laouami, Nasser;Slimani, Abdennasser
    • Earthquakes and Structures
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    • v.13 no.1
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    • pp.79-87
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    • 2017
  • Seismic analysis of local site conditions is fundamental for a reliable site seismic hazard assessment. It plays a major role in mitigation of seismic damage potential through the prediction of surface ground motion in terms of amplitude, frequency content and duration. Such analysis requires the determination of the transfer function, which is a simple tool for characterizing a soil profile by estimating its vibration frequencies and its amplification potential. In this study, numerical simulations are carried out and are then combined with a statistical study to allow the characterization of design sites classified by the Algerian Building Seismic Code (RPA99, ver 2003), by average transfer functions. The mean transfer functions are thereafter used to compute RPA99 average site factors. In this regard, coming up seismic fields are simulated based on Power Spectral Density Functions (PSDF) defined at the rock basement. Results are also used to compute average site factor where, actual and synthetic time histories are introduced. In absence of measurement data, it is found that the proposed approach can be used for a better soil characterization.