• 제목/요약/키워드: Two-step solution

검색결과 497건 처리시간 0.031초

유도형 축방향 모터의 6축력 제어를 이용한 대회전 구현용 통합 구동기 (Integrated Driver for the Full Rotation Using Six-axial Forces by the Induction Type of Axial-gap Motor)

  • 정광석;이상헌
    • 제어로봇시스템학회논문지
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    • 제12권8호
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    • pp.798-804
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    • 2006
  • To overcome the limited relative uncertainty and work range of the existing planar stage and the bulk structure of the contact-less motor for rotation, the novel operating principle to realize the precise rotation is suggested. It uses the two-axial vector forces, normal force and thrust force, of three-induction type of axial motors located $120^{\circ}$ apart, resulting in the contact-free rotation of the mover. Firstly in this paper, the magnetic forces across the air gap are modeled and simulated under the various conditions. It clarifies the feasible range of the derived solution. And the algorithm compensating the strong cross couple between the forces and the control inputs; generally AC magnitude and slip frequency, is given to realize the independent control of six axes. Finally, for the successfully implemented system, the round test and the micro step test results are given.

Fabrication of the piezoresistive pressure sensor using implantation steps

  • 홍근기;정예초;조준희;홍순관;김철주
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.559-560
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    • 2006
  • The paper presents solutions of conventional piezoresistive pressure sensors. Deflection of diaphragm by external stress causes some problems, because the electrode is deposited on the diaphragm formed piezoresistors. To solve these problems, piezoresistors is formed by two implantation steps. To fabricate diaphragm, the backside silicon etching step is done by immersing the wafer into TMAH solution. $30{\mu}m$ thick diaphragm is obtained. Sensitivity of the piezoresistive pressure sensor fabricated is 48.6 mV/V-psi.

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아날로그 신경 회로망을 이용한 스테레오 정합 (Stereo Matching Using Analog Neural Network)

  • 도경훈;이준재;조석제;이왕국;하영호
    • 전자공학회논문지B
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    • 제30B권6호
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    • pp.59-66
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    • 1993
  • Stereo vision is useful in obtaining three dimensional depth information from two images taken from different view points. Neural network modeling for stereo matching, the key step in stereo vision, is defined by an energy function satisfying with three constraints proposed by Marr and Poggio. Stereo matching is then carried out through the network to find minimum energy corresponding to the optimized solution of the problem. An algorithm for stereo matching using an analog neural network is presented here. The network can reduce errors in initial state an early iteration steps by adoption of continuous sigmoid function in stead of binary state. The experimental results show good matching performance for sparse random dot stereogram and real image.

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Genetic Algorithm Approach to Image Reconstruction in Electrical Impedance Tomography

  • Kim, Ho-Chan;Boo, Chang-Jin;Lee, Yoon-Joon;Kang, Chang-Ik
    • KIEE International Transactions on Electrophysics and Applications
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    • 제4C권3호
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    • pp.123-128
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    • 2004
  • In electrical impedance tomography (EIT), the internal resistivity distribution of the unknown object is computed using the boundary voltage data induced by different current patterns using various reconstruction algorithms. This paper presents a new image reconstruction algorithm based on the genetic algorithm (GA) via a two-step approach for the solution of the EIT inverse problem, in particular for the reconstruction of "static" images. The computer simulation for the 32 channels synthetic data shows that the spatial resolution of reconstructed images in the proposed scheme is improved compared to that of the modified Newton-Raphson algorithm at the expense of an increased computational burden.rden.

경계요소법을 사용한 선형 점탄성문제의 해석 (Analysis of linear viscoelastic problems using boundary element method)

  • 심우진;곽병만
    • 대한기계학회논문집
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    • 제11권2호
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    • pp.322-330
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    • 1987
  • 본 논문에서는 전자의 해석중에서 유한요소와 경계요소의 결합으로 생기는 문 제점 그리고 증가된 자요도로 인한 경제성의 손실 등을 고려하여 2차의 경계요소만을 사용한 경계요소법을 시도하였으며 다른 형태의 점탄성기본해 및 점탄성 경계적분식을 유도 사용하였다. 그리고 시도된 방법의 타당성을 보이기 위하여 사용된 예제들(평 면변형문제)의 이론해를 상응원리를 사용하여 유도하였으며 이를 수치결과와 비교하여 근사해의 정확함을 알 수가 있었다.

A Study on the Environmental Hormone

  • Chil Nam, Choi;Eun Jung, Na
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2001년도 정기총회 및 봄 학술발표회 초록집
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    • pp.193-194
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    • 2001
  • To determine for the hybridization, we have investigated by UV spectroscopic method. This complex behavior as nonelectrolytes in polar aprotic solution with molar conductivities. The technoques of pulse and cyclic voltammetry have been applied to the determination of $(E_{1/2})_{2}$-$(E_{1/2})_{1}$ for two-step electrochemical charge transfers. A simple amplitude has been derived for the dependence of the differential-pulse response on $(E_{1/2})_{1}$ and $(E_{1/2})_{2}$. The use of the peak-to-peak separation in cyclic voltammetry has also been evaluated. Comparison with a differential pulse and cyclic voltammetry methods shows agreement of comproportionation constant$(K_{c})$ within 50%.

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Analysis of thermo-rheologically complex structures with geometrical nonlinearity

  • Mahmoud, Fatin F.;El-Shafei, Ahmed G.;Attia, Mohamed A.
    • Structural Engineering and Mechanics
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    • 제47권1호
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    • pp.27-44
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    • 2013
  • A finite element computational procedure for the accurate analysis of quasistatic thermorheological complex structures response is developed. The geometrical nonlinearity, arising from large displacements and rotations (but small strains), is accounted for by the total Lagrangian description of motion. The Schapery's nonlinear single-integral viscoelastic constitutive model is modified for a time-stress-temperature-dependent behavior. The nonlinear thermo-viscoelastic constitutive equations are incrementalized leading to a recursive relationship and thereby the resulting finite element equations necessitate data storage from the previous time step only, and not the entire deformation history. The Newton-Raphson iterative scheme is employed to obtain a converged solution for the non-linear finite element equations. The developed numerical model is verified with the previously published works and a good agreement with them is found. The applicability of the developed model is demonstrated by analyzing two examples with different thermal/mechanical loading histories.

Low Resolution Rate Face Recognition Based on Multi-scale CNN

  • Wang, Ji-Yuan;Lee, Eung-Joo
    • 한국멀티미디어학회논문지
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    • 제21권12호
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    • pp.1467-1472
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    • 2018
  • For the problem that the face image of surveillance video cannot be accurately identified due to the low resolution, this paper proposes a low resolution face recognition solution based on convolutional neural network model. Convolutional Neural Networks (CNN) model for multi-scale input The CNN model for multi-scale input is an improvement over the existing "two-step method" in which low-resolution images are up-sampled using a simple bi-cubic interpolation method. Then, the up sampled image and the high-resolution image are mixed as a model training sample. The CNN model learns the common feature space of the high- and low-resolution images, and then measures the feature similarity through the cosine distance. Finally, the recognition result is given. The experiments on the CMU PIE and Extended Yale B datasets show that the accuracy of the model is better than other comparison methods. Compared with the CMDA_BGE algorithm with the highest recognition rate, the accuracy rate is 2.5%~9.9%.

Synthesis and characterization of polyimides for FPC applications

  • Yeon, J.H.;Bae, Y.U.;Yoon, T.H.
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.227-227
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    • 2006
  • It was attempted to synthesize polyimides from PPMDA and 3FPPMDA with mDAPPO/pPDA in order to afford CTE of 17ppm and adhesion property of 80g/mm, besides high Tg (>$300^{\circ}C$), good thermal stability (>$500^{\circ}C$), low water absorption and good solubility. The polyimides were prepared via a conventional two-step process; preparation of poly(amic-acid), followed by solution imidization by refluxing in NMP with o-DCB and the molar ratio of mDAPPO/pPDA was varied. The polyimides were characterized by FT-IR, NMR, DSC and TGA. In addition, intrinsic viscosity, solubility and coefficient of thermal expansion (CTE) were also measured.

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ACCELERATED STRONGLY CONVERGENT EXTRAGRADIENT ALGORITHMS TO SOLVE VARIATIONAL INEQUALITIES AND FIXED POINT PROBLEMS IN REAL HILBERT SPACES

  • Nopparat Wairojjana;Nattawut Pholasa;Chainarong Khunpanuk;Nuttapol Pakkaranang
    • Nonlinear Functional Analysis and Applications
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    • 제29권2호
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    • pp.307-332
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    • 2024
  • Two inertial extragradient-type algorithms are introduced for solving convex pseudomonotone variational inequalities with fixed point problems, where the associated mapping for the fixed point is a 𝜌-demicontractive mapping. The algorithm employs variable step sizes that are updated at each iteration, based on certain previous iterates. One notable advantage of these algorithms is their ability to operate without prior knowledge of Lipschitz-type constants and without necessitating any line search procedures. The iterative sequence constructed demonstrates strong convergence to the common solution of the variational inequality and fixed point problem under standard assumptions. In-depth numerical applications are conducted to illustrate theoretical findings and to compare the proposed algorithms with existing approaches.