• 제목/요약/키워드: Modelling Error

검색결과 278건 처리시간 0.025초

원형공동의 점진적인 붕락에 따른 지표침하특성 (Surface Subsidence according to Progressive Collapse of Circular opening)

  • 지정배;김종우
    • 터널과지하공간
    • /
    • 제10권1호
    • /
    • pp.33-44
    • /
    • 2000
  • 이 연구에서는 지하공동의 점진적인 붕락이 지표침하에 미치는 영향을 조사하기 위하여, 주문진산 표준사를 이용하여 모형지반을 구성하였으며, 공동의 심도를 달리하는 6가지 모델에 대하여 실내 모형실험을실시하였다. 여기서 공동의 심도와 붕락구간의 크기에 따른 침하발생양상을 조사하였다. 또한 NCB 방법, 지수함수를 이용한 윤곽함수법 영향함수법 등의 침하예측방법을 이용하여 모형실험으로부터 측정된 수직 및 수평변위를 해석하였으며, 모래지반에 적합한 침하예측방법을 제안하였다.

  • PDF

역해석 기법에 근거한 수직배수재로 개량된 연약점토지반의 침하예측 (Prediction of Settlement of Vertical Drainage-Reinforced Soft Clay Ground using Back-Analysis)

  • 박현일;김윤태;황대진
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 지반공학 공동 학술발표회
    • /
    • pp.417-424
    • /
    • 2005
  • Observed field behaviors are frequently different from the behaviors predicted in the design state due to several uncertainties involved in soil properties, numerical modelling, and error of measuring system even though a sophisticated numerical analysis technique is applied to solve the consolidation behavior of drainage-installed soft deposits. In this study, genetic algorithms are applied to back-analyze the soil properties using the observed behavior of soft clay deposit composed of multi layers that shows complex consolidation characteristics. Utilizing the program, one might be able to appropriately predict the subsequent consolidation behavior from the measured data in an early stage of consolidation of multi layered soft deposits. Example analyses for drainage-installed multi-layered soft deposits are performed to examine the applicability of proposed back-analysis method.

  • PDF

제어구조 변경과 신경망 보정에 의한 적응제어에 관한 연구 (A Research on the Adaptive Control by the Modification of Control Structure and Neural Network Compensation)

  • 김윤상;이종수;최경삼
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
    • /
    • pp.812-814
    • /
    • 1999
  • In this paper, we propose a new control algorithm based on the neural network(NN) feedback compensation with a desired trajectory modification. The proposed algorithm decreases trajectory errors by a feed-forward desired torque combined with a neural network feedback torque component. And, to robustly control the tracking error, we modified the desired trajectory by variable structure concept smoothed by a fuzzy logic. For the numerical simulation, a 2-link robot manipulator model was assumed. To simulate the disturbance due to the modelling uncertainty. As a result of this simulation, the proposed method shows better trajectory tracking performance compared with the CTM and decreases the chattering in control inputs.

  • PDF

동적 신경회로망을 이용한 비선형 크레인 시스템의 위치제어 (Position Control of Nonlinear Crane Systems using Dynamic Neural Network)

  • 한승훈;조현철;이권순
    • 전기학회논문지
    • /
    • 제56권5호
    • /
    • pp.966-972
    • /
    • 2007
  • This paper presents position control of nonlinear three-dimensional crane systems using neural network approach. Such crane system generally includes very complicated characteristic dynamics and mechanical framework such that its mathematical model is expressed by strong nonlinearity. This leads difficulty in control design for the systems. We linearize the nonlinear system model to construct PID control applying well-known linear control theory and then neural network is utilized to compensate system perturbation due to linearization. Thus, control input of the crane system is composed of nominal PID and neural output signals respectively. Our method illustrates simple design procedure, but system perturbation and modelling error are overcome through a neural compensator. As well. adaptive neural control is constructed from online learning. Computer simulation demonstrates our control approach is superior to the classic control systems.

Analysis of corrugated board panels under compression load

  • Biancolini, M.E.;Brutti, C.;Porziani, S.
    • Steel and Composite Structures
    • /
    • 제9권1호
    • /
    • pp.1-17
    • /
    • 2009
  • This paper is focused on the buckling and post buckling behaviour of rectangular corrugated board panels simply supported and subjected to compression load. The aim of the work is to understand the failure mechanism of investigated structure in order to quantify the effect of design parameters on the strength of a panel of given geometry. Two numerical models were developed adopting the finite element method. In the first one the corrugated board is represented by means of shell elements adopting an equivalent material, in the second the local structure is described in full detail modelling both straight and corrugated layers by means of shell elements and representing the connection between layers by special interface elements. The model correctness was checked by the comparison between out of plane central displacement predicted by the models and the experimental values found in literature. For the same case the effect of panel planarity error was evaluated. Finally a parametric analysis to investigate the effect of design parameters was carried out.

Digital Modelling of Visual Perception in Architectural Environment

  • Seo, Dong-Yeon;Lee, Kyung-Hoi
    • KIEAE Journal
    • /
    • 제3권2호
    • /
    • pp.59-66
    • /
    • 2003
  • To be the design method supporting aesthetic ability of human, CAAD system should essentially recognize architectural form in the same way of human. In this study, visual perception process of human was analyzed to search proper computational method performing similar step of perception of it. Through the analysis of visual perception, vision was separated to low-level vision and high-level vision. Edge detection and neural network were selected to model after low-level vision and high-level vision. The 24 images of building, tree and landscape were processed by edge detection and trained by neural network. And 24 new images were used to test trained network. The test shows that trained network gives right perception result toward each images with low error rate. This study is on the meaning of artificial intelligence in design process rather than on the design automation strategy through artificial intelligence.

공기제동 시스템의 감속도 제어기 설계 (Design of Deceleration Controller for Air Braking System)

  • 이광국;김원경;김명룡;윤성철;백광선
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2004년도 춘계학술대회 논문집
    • /
    • pp.696-701
    • /
    • 2004
  • Electric vehicle that is manufactured present by development of electric vehicle technology were available automatic driving. Control of air breaking system for precision stopping is important at automatic driving. Current Electric vehicle is doing precision stopping using braking force control. Braking force control is difficult to take static deceleration by rail condition or change of friction coefficient. Therefore, Proposed the controller in this study is deceleration controller. Designed controller is a robust controller that take state control characteristic for modelling error.

  • PDF

용도지역. 지구 자료간 불부합 해결을 위한 데이터모델링에 관한 연구 (A data modelling for the inconsistency resolving on zoning data)

  • 최병남;김대종;이권한
    • Spatial Information Research
    • /
    • 제8권1호
    • /
    • pp.1-14
    • /
    • 2000
  • 국토이용계획도, 도시계획도, 농업진흥지역도, 산지이용구분도 등 용도지역·지구 자료는 법적·공간적 특성으로 자료간 연관성을 가지고 있다. 그러나 부처별·부서별 제도운용에 따른 자료공유의 어려움, 수작업체계에 의한 용도지역·지구 경계선의 저확성 한P 등으로 자료간의 관계가 일관성이 결여되어 토지 이용에 많은 문제가 발생하고 있다. 이 연구에서는 GIS의 중첩기법을 이용하여 용도지역·지구 자료간 불부합 실태와 원인을 분석하고, 이러한 문제를 해결할 수 있는 방안으로서 자료간 연관성을 고려한 데이터모델링 방안을 제시하였다.

  • PDF

증기발생기 수위 제어를 위한 견실$H^{\infty}$ 제어기 설계 (Design of Robust $H^{\infty}$ Controller for Water Level Control of Steam Generator)

  • 서성환;조희수박홍배
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 하계종합학술대회논문집
    • /
    • pp.223-226
    • /
    • 1998
  • The control objective of steam generator water level in the secondary circuit of a nuclear power plant is to regulate the water level at the desired set point. The dynamics of steam generators is non-linear in nature. The task of modelling such plant is very difficult and especially so when plant operating conditions change frequently. In these reasons, conventional PI gains over all pover range will not work efficiently and a manual control is generally used in low power operation. Therefore the robust H$\infty$ controller design method should be required. In this paper, we design the robust H$\infty$ controller for water level control of steam generator using a mixed H$\infty$ optimization with model-matching method. Firstly we choose the desired model that has good disturbance rejection performance. Secondly we design a stabilizing controller to keep the model-matching error small and also provide sufficiently large stability margin against additive perturbations of the nominal plant.

  • PDF

직접 적응제어방식에 의한 로봇 머니퓰레이터의 견실한 제어기 설계에 관한 연구 (A Study on Robust Controller Design of Robotic Manipulator Using Direct Adaptive Control)

  • 한성현;박한일
    • 한국해양공학회지
    • /
    • 제3권2호
    • /
    • pp.559-559
    • /
    • 1989
  • This paper deals with the robust controller design of robot manipulator to track a desired trajectory in spite of the presence of unmodelled dynamics in cause of nonlinearity and parameter uncertainty. The approach follwed in this paper is based on model reference adaptive control technique and convergence on hyperstability theory but it does away with the assumption that process is characterized by a linear model remaining time invariant during adaptation process. The performance of controller is demonstrated by computed simulation about position and speed control of six link manipulator in case of disturbance and payload variation.