• Title/Summary/Keyword: Weak convergence.

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The Electrical Characterization and Relaxation Behavior of Ag(Ta0.8Nb0.2)O3 Ceramics

  • Kim, Young-Sung;Kim, Jae-Chul;Jeong, Tae-Hoon;Nam, Sung-Pill;Lee, Seung-Hwan;Kim, Hong-Ki;Lee, Ku-Tak
    • Transactions on Electrical and Electronic Materials
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    • v.15 no.2
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    • pp.100-102
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    • 2014
  • $Ag(Ta,Nb)O_3$ materials have a perovskite structure with a low loss tangent. These materials have been widely researched for their applications as high-frequency, passive components. Also, $Ag(Ta,Nb)O_3$ materials have weak frequency dispersion with high dielectric permittivity which gives them enormous potential for use in electronic components, including the filters, and embedded capacitors. Therefore, our research will discuss the structural and electrical relaxation properties of $Ag(Ta_{0.8}Nb_{0.2})O_3$ ceramics for device applications. We will investigate using X-ray diffraction to understand their structural properties and will analyze voltage dependent leakage current and timedependent relaxation behavior to understand their material properties.

A study on Secure Communication in Hyper-Chaos with SC-CNN using Embedding Method

  • Bae, Young-Chul;Kim, Ju-Wan;Song, Hag-Hyun;Kim, Yoon-Ho
    • Journal of information and communication convergence engineering
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    • v.1 no.4
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    • pp.223-228
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    • 2003
  • In this paper, we introduce a hyper-chaos secure communication method using hyper-chaos circuit onsist of State-Controlled Cellular Neural Network SC-CNN). We make a hyper-chaos circuit using SC-CNN with the n-double scroll or Chua's oscillator. A hyper-chaos circuit is created by applying identical n-double scroll or non-identical n-double scroll and Chua's oscillator with weak coupled method to each cell. Hyper-chaos ynchronization was achieved using GS (Generalized Synchronization) method between the transmitter and receiver about each state variable in the SC-CNN. In order to secure communication, we have synthesizing the desired information with a hyper-chaos circuit by adding the information signal to the hyper-chaos signal using the SC-CNN in the transmitter. And then, transmitting the synthesized signal to the ideal channel, we confirm secure communication by separating the information signal and the hyper-chaos signal in the receiver.

Fuzzy Simulation of a Multi-electronic Acupuncture System and Clip-type Pulsimeter Equipped with a Magnetic Sensing Hall Device

  • Hong, You-Sik;Rhee, Jin-Kyu;Kim, Han-Kyu;Son, Il-Ho;Yoon, Woo-Sung;Lee, Nam-Kyu;Park, Do-Young;Kim, Keun-Ho;Kim, Yong-Jin;Khajidmaa, P.;Lee, Sang-Suk
    • Journal of Magnetics
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    • v.19 no.3
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    • pp.255-260
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    • 2014
  • A portable clip-type pulsimeter equipped with a magnetic sensing Hall device has been developed to raise the accuracy of oriental disease diagnosis and therapy by convergence of magnetism and oriental medicine. To improve accuracy and reliability of conventional pulsimeter due to subjective analysis of the pulse wave and measuring position dependency of the arterial pulse sensor, the fuzzy algorithm was applied to analyze the strong- and weak-pulse wave symptom. Optimal time for electronic acupuncture was calculated using fuzzy rules and interference were drawn from objective data in view of pre-treatment. Moreover, the electrical characteristics of the pain parts that respond to acupuncture point were applied in view of post-treatment to propose the scientific pulse wave algorithm and simulation experiment.

The Generative Mechanism of Cloud Streets

  • Kang Sung-Dae;Kimura Fujio
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.1 no.2
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    • pp.119-124
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    • 1997
  • Cloud streets were successfully simulated by numerical model (RAMS) including an isolated mountain near the coast, large sensible heat flux from the sea surface, uniform stratification and wind velocity with low Froude number (0.25) in the inflow boundary. The well developed cloud streets between a pair of convective rolls are simulated at a level of 1 km over the sea. The following five results were obtained: 1) For the formation of the pair of convective rolls, both strong static instability and a topographically induced mechanical disturbance are strongly required at the same time. 2) Strong sensible heat flux from the sea surface is the main energy source of the pair of convective rolls, and the buoyancy caused by condensation in the cloud is negligibly small. 3) The pair of convective rolls is a complex of two sub-rolls. One is the outer roll, which has a large radius, but weak circulation, and the other is the inner roll, which has a small radius, but strong circulation. The outer roll gathers a large amount of moisture by convergence in the lower marine boundary, and the inner roll transfers the convergent moisture to the upper boundary layer by strong upward motion between them. 4) The pair of inner rolls form the line-shaped cloud streets, and keep them narrow along the center-line of the domain. 5) Both by non-hydrostatic and by hydrostatic assumptions, cloud streets can be simulated. In our case, non-hydrostatic processes enhanced somewhat the formation of cloud streets. The horizontal size of the topography does not seem to be restricted to within the small scale where non-hydrostatic effects are important.

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A Study and Review of Gender Inequality Index (국제지표로 살펴 본 성평등지수)

  • Seong, Moonju
    • Journal of Digital Convergence
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    • v.14 no.6
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    • pp.43-49
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    • 2016
  • This paper explains concepts and methods of indexes measuring gender gaps. There are mainly 4 indexs, GDI, GEM, GII and GGI. UNDP developed GDI, GEM and GII. WEF developed GGI. Each index has its own strengths and weak points. Therefore it is important to understand each index in detail. For Korea, as men and women have been developed equally in areas of education and health, the GDI score was in a high group. However, the GEM and GGI scores were low. This implies that in order to reduce gender gaps, it is necessary to expand gender equality policies empowering economic and political empowerment.

Simulation of Low Temperature Plasmas for an Ultra Violet Light Source using Coplanar Micro Dielectric Barrier Discharges

  • Bae, Hyowon;Lee, Ho-Jun;Lee, Hae June
    • Applied Science and Convergence Technology
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    • v.25 no.6
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    • pp.138-144
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    • 2016
  • The discharge characteristics of pulse-driven coplanar micro barrier discharges for an ultraviolet (UV) light source using Ne-Xe mixture have been investigated using a two-dimensional fluid simulation at near-atmospheric pressure. The densities of electrons, the radiative excited states, the metastable excited states, and the power loss are investigated with the variations of gas pressure and the gap distance. With a fixed gap distance, the number of the radiative states $Xe^*(^3P_1)$ increases with the increasing driving voltage, but this number shows weak dependency on the gas when that pressure is over 400 Torr. However, the number of the radiative states increases with the increase of the gap distance at a fixed voltage, while the power loss decreases. Therefore, a long gap discharge has higher efficiency for UV generation than does a short gap discharge. A slight change in the electrode tilt angle enhances the number of radiative species 2 or 3 times with the same operation conditions. Therefore, the intensity and efficiency of the UV light source can be controlled independently by changing the gap distance and the electrode structure.

FMC Performance and Voice Quality of Enterprise Type connectable to IP-PBX (IP-PBX와 연동 가능한 기업 형 FMC 성능 및 음성품질)

  • Kim, Sam-Taek
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.89-94
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    • 2015
  • FMS which has a concept that wireless terminal can replace wire terminal services is a technologies that is can provide service costs same as wire terminal in the special zone. Enterprise type of FMC that is developed making up for the weak point is must have to improve voice quality and FMC performance in the soft phone. This paper measure voice quality based on the one way of the total estimated delay time of FMC to carry out IMS services between IP-PBX and FMC soft-phone to operate it's controller optimally and put forward evidence to be in 120ms and 150ms in the VoIP FMC voice quality. To measure FMC performances in four categories evaluated trials and prove its performances.

Analysis of Accounting Information Systems Consulting Effects (회계정보시스템 컬설팅 효과 분석)

  • Kim, Dong-Il;Choi, Seung-Il
    • Journal of Digital Convergence
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    • v.11 no.10
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    • pp.351-357
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    • 2013
  • This research studied that the effect of consulting local SMEs focusing on the effective factors related to quality of theoretical study and the previous studies according to research model and research hypotheses. Also, in this empirical analysis, analyzed the consulting performance that distinguish such as consulting procedures quality, consulting adaptation, consultant emotional intelligence and efforts factors. Second, in relationship with consulting adaptation and performance, statistically significant relationship showed weak. Finally, the quality of the consultant engagement and emotional intelligence was analyzed high significance. Therefore, this study further accounting information systems consultant at consultant emotional intelligence factors can expect a useful guidelines.

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.

Efficient finite element model for dynamic analysis of laminated composite beam

  • Naushad Alam, M.;Upadhyay, Nirbhay Kr.;Anas, Mohd.
    • Structural Engineering and Mechanics
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    • v.42 no.4
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    • pp.471-488
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    • 2012
  • An efficient one dimensional finite element model has been presented for the dynamic analysis of composite laminated beams, using the efficient layerwise zigzag theory. To meet the convergence requirements for the weak integral formulation, cubic Hermite interpolation is used for the transverse displacement ($w_0$), and linear interpolation is used for the axial displacement ($u_0$) and shear rotation (${\psi}_0$). Each node of an element has four degrees of freedom. The expressions of variationally consistent inertia, stiffness matrices and the load vector are derived in closed form using exact integration. The formulation is validated by comparing the results with the 2D-FE results for composite symmetric and sandwich beams with various end conditions. The employed finite element model is free of shear locking. The present zigzag finite element results for natural frequencies, mode shapes of cantilever and clamped-clamped beams are obtained with a one-dimensional finite element codes developed in MATLAB. These 1D-FE results for cantilever and clamped beams are compared with the 2D-FE results obtained using ABAQUS to show the accuracy of the developed MATLAB code, for zigzag theory for these boundary conditions. This comparison establishes the accuracy of zigzag finite element analysis for dynamic response under given boundary conditions.