• Title/Summary/Keyword: Bilinear Model

Search Result 253, Processing Time 0.025 seconds

Bond-Slip Model of Interface between Concrete Structures and CFRP Sheets (탄소섬유시트와 콘크리트 구조물의 부착-슬립 모델)

  • Kang, Suk-Hwa;Kim, Ho-Jin;Nam, Jin-Won;Lee, Woo-Cheol;Yoo, Yong-Ha;Byun, Keun-Joo
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2006.11a
    • /
    • pp.113-116
    • /
    • 2006
  • In this study, new bond-slip model is proposed. The proposed bond-slip model which has bilinear ascending regions and exponential descending region by modifying the conventional bilinear bond-slip model has been verified. Then, result by finite element analyses using interface element implemented with bond-slip model compared well with those of existing experiment researches on bond-slip models. It is shown that bond strength and effective bond length predicted by the bond-slip model and finite element analysis is good agreement with those of pull tests.

  • PDF

Bond-Slip Model for CFRP Sheet-Concrete Adhesive Joint (탄소섬유쉬트-콘크리트 부착이음의 부착 모델)

  • Cho, Jeong-Rae;Cho, Keunhee;Park, Young-Hwan;Park, Jong-Sup
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.26 no.2A
    • /
    • pp.285-292
    • /
    • 2006
  • In this study, a method determining the local bond-slip model from pure shear test results of CFRP sheet-concrete adhesive joints is proposed and local bond-slip models are presented. Adhesive joints with a specific bond-slip model, which is assumed as multi-linear curve in order to represent arbitary function, are solved numerically. The difference between the solution and test results are minimized for finding the bond-slip model. The model with bilinear curve is also optimized to verify the improvement of multi-linear model. The selected test results are ultimate load-adhesive length curves from a series of adhesive joints and load-displacement curves for each joint. The optimization problem is formulated by physical programming, and the optimized bond-slip model is found using genetic algorithm.

Robust Stabilization of Uncertain LTI Systems via Observer Model Selection (관측기 모델 선정을 통한 모델 불확실성을 갖는 선형 시불변 시스템 강인 안정화)

  • Oh, Sangrok;Kim, Jung-Su;Shim, Hyungbo
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.8
    • /
    • pp.822-827
    • /
    • 2014
  • This paper presents a robust observer-based output feedback control for stabilization of linear time invariant systems with polytopic uncertainties. To this end, this paper not only finds a robust observer gain but also suggests how to determine the model used in the observer, which is not obvious due to model uncertainties in the conventional observer design method. The robust observer gain and the observer model are selected in a way that the whole closed-loop is stable by solving LMIs and BMIs (Linear Matrix Inequalities and Bilinear Matrix Inequalities). A simulation example shows that the proposed robust observer-based output feedback control successfully leads to closed-loop stability.

Beam-Column Element Applicable to Nonlinear Seismic Analysis (비선형 지진 해석을 위한 보-기둥 요소)

  • Kim, Kee Dong;Ko, Man Gi;Lee, Sang Soo
    • Journal of Korean Society of Steel Construction
    • /
    • v.9 no.4 s.33
    • /
    • pp.557-578
    • /
    • 1997
  • The objective of the study in this paper was to develop a beam-column element to model members with purely flexural yielding, as well as members with yielding under combined flexure and axial force during severe earthquake ground motins. The developed element can be considered as an one-component series hinge type model. It has the capability to model plastic axial deformation and changes in axial stiffness, and employs hardening rules to handle monotonic, cyclic or arbitrary loading. In general, when compared to experimental results and fiber model predictions, the element showed significantly better performance than the bilinear hinger model and could properly model the beam-column behavior of bare steel members in moment resisting frames. The developed element can more accurately predict local deformation demands and overall responses of structural systems under earthquake loadings than the bilinear hinge element.

  • PDF

Bond-Slip Model of Interface between CFRP Sheets and Concrete Beams Strengthened with CFRP (탄소섬유시트로 보강된 콘크리트보의 경계면 부착-슬립모델)

  • Kim, Sung-Bae;Kim, Jang-Ho Tay;Nam, Jin-Won;Kang, Suk-Hwa;Byun, Keun-Joo
    • Journal of the Korea Concrete Institute
    • /
    • v.20 no.4
    • /
    • pp.477-486
    • /
    • 2008
  • External bonding of carbon fiber reinforced plastic sheets has recently emerged as a popular method for strengthening reinforced concrete structures. The behavior of CFRP-strengthened RC structure is often controlled by the behavior of the interface between CFRP sheets and concrete. In this study, a review of models on bond strength, bond-slip, and interfacial stresses has been first carried out. Then a new bond-slip model is proposed. The proposed bond-slip model has bilinear ascending regions and exponential descending region derived from modifications mode on the conventional bilinear bond-slip model. The comparison of the results with those of existing experiment researches on bond-slip models indicate good agreements.

Efficient Fuzzy Identity-Based Encryption Scheme (효율적인 퍼지 아이디 기반 암호화 방법)

  • Lee, Kwang-Su;Lee, Dong-Hoon
    • 한국정보통신설비학회:학술대회논문집
    • /
    • 2008.08a
    • /
    • pp.563-565
    • /
    • 2008
  • In this paper, we construct an efficient fuzzy identity-based encryption scheme in the random oracle model. The fuzzy identity-based encryption is an extension of identity-based encryption schemes where a user's public key is represented as his identity. Our construction requires constant number of bilinear map operations for decryption and the size of private key is small compared with the previous fuzzy identity-based encryption of Sahai-Waters. We also presents that our fuzzy identity-based encryption can be converted to attribute-based encryption schemes.

  • PDF

Satellite communication Equalizer Using Complex Bilinear Recurrent Neural Network (C-BLRNN을 이용한 위성채널 등화기)

  • 박동철;정태균
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.25 no.3A
    • /
    • pp.375-382
    • /
    • 2000
  • Equalization of satellite communication using Complex-Bilinear Recurrent Neural Network(C-BLRNN) is proposed in this pater. Since the BLRNN is based on the bilinear polynomial and it has been more effectively used in modeling highly nonlinear systems with time-series characteristics than multi-layer perception type neural networks(MLPNN) , it can be applied to satellite equalizer. the proposed C-BLRNN based equalizer for M-PSK with a channel model is compared with Volterra filter Equalizer, DFE, and conventional Complex MLPNN Equlizer. The results show that the proposed C-BLRNN based equalizer gives very favorable results in both of MSE and BER criteria over other equalizers.

  • PDF

Earthquake response spectra estimation of bilinear hysteretic systems using random-vibration theory method

  • Yazdani, Azad;Salimi, Mohammad-Rashid
    • Earthquakes and Structures
    • /
    • v.8 no.5
    • /
    • pp.1055-1067
    • /
    • 2015
  • A theoretical procedure to estimate spectral displacement of a hysteretic oscillator with bilinear stiffness excited by band-limited excitation is presented. The stochastic method of ground-motion simulation is combined with the random vibration theory to compute linear and nonlinear structural response. The response is obtained by computing the root-mean-square oscillator response using dissipation energy balancing by integrating over all energy levels of system weighting with the stationary probability density of the energy. The results are presented in a convenient form, and the accuracy of the procedure is assessed by comparison with results obtained with the time-domain method using the recorded data. The model shows little or no bias at the structural period of engineering interest.

Efficient and Secure Certificateless Proxy Re-Encryption

  • Liu, Ya;Wang, Hongbing;Wang, Chunlu
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.11 no.4
    • /
    • pp.2254-2275
    • /
    • 2017
  • In this paper, we present an IND-CCA2 secure certificateless proxy re-encryption scheme in the random oracle model. A certificateless public key cryptography simplifies the certificate management in a traditional public key infrastructure and the built-in key escrow feature in an identity-based public key cryptography. Our scheme shares the merits of certificateless public key encryption cryptosystems and proxy re-encryption cryptosystems. Our certificateless proxy re-encryption scheme has several practical and useful properties - namely, multi-use, unidirectionality, non-interactivity, non-transitivity and so on. The security of our scheme bases on the standard bilinear Diffie-Hellman and the decisional Bilinear Diffie-Hellman assumptions.

Steam Temperature Controller Design of Power Plant Superheater (발전기 과열기의 증기 온도 제어기 설계)

  • Hong, Hyun-Mun;Lee, Bong-Seob
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.9 no.3
    • /
    • pp.179-181
    • /
    • 2006
  • In this paper, we present a method of fuzzy controller design for the power plant superheater in the form of bilinear system. For the steam temperature control, the input variables are constructed by the area of difference between the profiles estimated from bilinear observer and reference profiles, and the time rate of change. We estimate the control rules by T. Takagi and M. Sugeno's fuzzy model. The feasibilities of the suggested method are illustrated via the computer simulation result.

  • PDF