• Title/Summary/Keyword: mapping model

Search Result 1,449, Processing Time 0.03 seconds

Neural Networks Based Modeling with Adaptive Selection of Hidden Layer's Node for Path Loss Model

  • Kang, Chang Ho;Cho, Seong Yun
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.8 no.4
    • /
    • pp.193-200
    • /
    • 2019
  • The auto-encoder network which is a good candidate to handle the modeling of the signal strength attenuation is designed for denoising and compensating the distortion of the received data. It provides a non-linear mapping function by iteratively learning the encoder and the decoder. The encoder is the non-linear mapping function, and the decoder demands accurate data reconstruction from the representation generated by the encoder. In addition, the adaptive network width which supports the automatic generation of new hidden nodes and pruning of inconsequential nodes is also implemented in the proposed algorithm for increasing the efficiency of the algorithm. Simulation results show that the proposed method can improve the neural network training surface to achieve the highest possible accuracy of the signal modeling compared with the conventional modeling method.

Application of Empirical Models for Estimation of Surface Parameters (지표면 매개변수 추정을 위한 경험상의 모델 활용)

  • 양민실;문우일
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
    • /
    • 2003.04a
    • /
    • pp.176-181
    • /
    • 2003
  • 이 논문은 나대지에서 획득한 polarimetric SAR 자료의 후방 산란 계수(backscattering coefficient) 분석을 위한 surface parameters 추출 및 forward mapping에 대하여 서술하였다. Surface parameter는 토양의 거칠기(ks), 수분 함량(m/sub v/), 유전 상수(ε/sub m/) 등이 포함되어 있고, 유전 상수의 추정을 위하여 0.3-1.3GHz 구간의 자료를 기반으로 제안된 N. R. Peplinski의 경험상의 모델(Empirical Model) 알고리즘을 사용하였다. 추정된 surface parameter는 polarimetric SAR 자료의 산란 현상을 특징짓기 위한 forward mapping의 입력 값으로 이용되었으며, scattering model로 Oh의 경험상의 모델을 사용하였다. 각각의 surface parameter ks, θ, m/sub v/는 Oh 모델을 이용한 시뮬레이션을 통하여 레이더 후방 산란 계수에 미치는 영향에 대하여 조사되었다.

  • PDF

Identification of Nonlinear Mapping based on Fuzzy Integration of Local Affine Mappings (국부 유사사상의 퍼지통합에 기반한 비선형사상의 식별)

  • 최진영;최종호
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.32B no.5
    • /
    • pp.812-820
    • /
    • 1995
  • This paper proposes an approach of identifying nonlinear mappings from input/output data. The approach is based on the universal approximation by the fuzzy integration of local affine mappings. A connectionist model realizing the universal approximator is suggested by using a processing unit based on both the radial basis function and the weighted sum scheme. In addition, a learning method with self-organizing capability is proposed for the identifying of nonlinear mapping relationships with the given input/output data. To show the effectiveness of our approach, the proposed model is applied to the function approximation and the prediction of Mackey-Glass chaotic time series, and the performances are compared with other approaches.

  • PDF

Development of Color Inspection System of Printed Texture using Scanner (스캐너를 이용한 직물의 색상검사기 개발)

  • 조지승;정병묵;박무진
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.20 no.8
    • /
    • pp.70-75
    • /
    • 2003
  • It is very important to inspect the color of printed texture in the textile process. The standard colorimetric system used for the recognition of the color in the textile industry. It uses XYZ color system defined by CIE (Commission Internationale de 1Eclairage), but is too expensive. Therefore, in this paper, we propose a color inspection system of the printed texture using a color scanner. Because the scanner uses RGB value for color, it is necessary the mapping from RGB to XYZ. However, the mapping is not simple, and the scanner has even positional deviation because of the geometric characteristics. To transform from RGB to XYZ, we used a NN (neural network) model and also compensated the positional deviation. In real experiments, we could get fairly exact XYZ value from the proposed color inspection system in spite of using a color scanner with large measuring area.

Anisotropic continuum damage analysis of thin-walled pressure vessels under cyclic thermo-mechanical loading

  • Surmiri, Azam;Nayebi, Ali;Rokhgireh, Hojjatollah;Varvani-Farahani, Ahmad
    • Structural Engineering and Mechanics
    • /
    • v.75 no.1
    • /
    • pp.101-108
    • /
    • 2020
  • The present study intends to analyze damage in thin-walled steel cylinders undergoing constant internal pressure and thermal cycles through use of anisotropic continuum damage mechanics (CDM) model coupled with nonlinear kinematic hardening rule of Chaboche. Materials damage in each direction was defined based on plastic strain and its direction. Stress and strain distribution over wall-thickness was described based on the CDM model and the return mapping algorithm was employed based on the consistency condition. Plastic zone expansion across the wall thickness of cylinders was noticeably affected with change in internal pressure and temperature gradients. Expansion of plastic zone over wall-thickness at inner and outer surfaces and their boundaries demarking elastic and plastic regions was attributed to the magnitude of damage induced over thermomechanical cycles on the thin-walled samples tested at various pressure stresses.

Simple model of interdigital capacitors for microwave applications (마이크로파 응용을 위한 Interdigital capacitor의 간단한 모델)

  • You, Hee-Wook;Lee, Myung-Shik;Kim, Dong-Ho;An, Ho-Myoung;Koh, Jung-Hyuk
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2005.11a
    • /
    • pp.198-199
    • /
    • 2005
  • Conformal mapping based models are given for interdigital capacitors on substrates with a thin superstrate and covering dielectric thin film. This model is useful for a wide range of dielectric constant and layer thickness. Interdigital capacitors with finger numbers n>3 are discussed.

  • PDF

Nonlinear Hinge Dynamics Estimation of Deployable Missile Control Fin (접는 미사일 조종날개의 비선형 힌지 동특성 파악)

  • Kim, Dae-Kwan;Bae, Jae-Sung;Lee, In;Woo, Sung-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2002.05a
    • /
    • pp.848-854
    • /
    • 2002
  • The nonlinear characteristics for the hinge of a deployable missile control fin are investigated experimentally. The nonlinearity is caused by a worn or loose hinge and manufacturing tolerance and cannot be eliminated completely. The structural nonlinearity has an effect on the static and dynamic characteristics of the control fin. Therefore, it is necessary to establish the accurate nonlinear model for the hinge of the control fin. In the present study the existence of nonlinearities in the hinge is confirmed from the frequency response experiments such as tip random excitation and base sine sweep. Using the system identification method, especially, “Force-State Mapping Technique”, the types of nonlinearities are identified and the nonlinear hinge model of the control fin is established.

  • PDF

Application of Conformal Mapping in Analysis the Parallel Stripline Resonator

  • Tran, T.H.;You, S.J.;Kim, J.H.;Seong, D.J.;Jeong, J.R.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2012.02a
    • /
    • pp.180-180
    • /
    • 2012
  • A microplasma system source based on microwave parallel stripline resonator (MPSR) was developed for the generation of microplasmas in a wide range of pressure from some torr to 760 torr. This source was operated at its resonance frequency that much depends upon not only its discharge gap size but also operated pressure. This paper applied a simple circuit model to analyze the effects of discharge gap size and pressure to resonance frequency and impedance of MPSR in the cases with and without plasma exist inside the discharge gap. In the process of calculating, the conformal mapping method was used to estimate the capacitance of the MPSR. The calculating results by using circuit model agree well with the simulation results that using commercial CST microwave studio software.

  • PDF

Torque Formularization of Harmonic Side Drive Motor by Cnformal Mapping (등각사상을 이용한 하모닉 모터의 토크 정식화)

  • Yun, S.J.;Lee, E.W.;Lee, D.J.;Lee, J.H.;Jeong, J.H.
    • Proceedings of the KIEE Conference
    • /
    • 1998.07a
    • /
    • pp.67-69
    • /
    • 1998
  • In order to design or predict the performance of a cylindrical electrostatic motor it is necessary to analyze the torque generated by such a structure. In this paper a simple but sufficiently accurate analytical model is developed for use in design. Conformal mapping are used to model the capacitance and torque of the motor as a function of the rotor position, using a quasi-static, two-dimension approximation, the effect of an insulating dielectric layer on the stator or rotor is also evaluated.

  • PDF

Improved Viewing Quality of 3-D Images in Computational Integral Imaging Reconstruction Based on Round Mapping Model

  • Shin, Dong-Hak;Kim, Nam-Woo;Yoo, Hoon;Lee, Joon-Jae;Lee, Byoung-Ho;Kim, Eun-Soo
    • ETRI Journal
    • /
    • v.29 no.5
    • /
    • pp.649-654
    • /
    • 2007
  • In this paper, we propose a computational integral imaging reconstruction (CIIR) method using a round mapping model to improve the viewing quality of 3-D images. The proposed CIIR method can overcome the problem of non-uniformly reconstructed images caused by the conventional method. To show the usefulness of proposed method, some experiments are carried out and the results are presented.

  • PDF