• 제목/요약/키워드: deterministic model

검색결과 582건 처리시간 0.025초

MATHEMATICAL ANALYSIS OF AN "SIR" EPIDEMIC MODEL IN A CONTINUOUS REACTOR - DETERMINISTIC AND PROBABILISTIC APPROACHES

  • El Hajji, Miled;Sayari, Sayed;Zaghdani, Abdelhamid
    • 대한수학회지
    • /
    • 제58권1호
    • /
    • pp.45-67
    • /
    • 2021
  • In this paper, a mathematical dynamical system involving both deterministic (with or without delay) and stochastic "SIR" epidemic model with nonlinear incidence rate in a continuous reactor is considered. A profound qualitative analysis is given. It is proved that, for both deterministic models, if ��d > 1, then the endemic equilibrium is globally asymptotically stable. However, if ��d ≤ 1, then the disease-free equilibrium is globally asymptotically stable. Concerning the stochastic model, the Feller's test combined with the canonical probability method were used in order to conclude on the long-time dynamics of the stochastic model. The results improve and extend the results obtained for the deterministic model in its both forms. It is proved that if ��s > 1, the disease is stochastically permanent with full probability. However, if ��s ≤ 1, then the disease dies out with full probability. Finally, some numerical tests are done in order to validate the obtained results.

제주 정낭(錠木) 채널 Code IV (Jeju Jong-Nang Channel Code IV)

  • 박주용;김정수;이문호
    • 한국인터넷방송통신학회논문지
    • /
    • 제16권3호
    • /
    • pp.73-80
    • /
    • 2016
  • "제주 정낭 Code I, II, III"에서는 배경과 역사 그리고 물리적 의미에 대해 알아보았다. "제주 정낭 Code II" 논문에서는 디지털휴먼 이진 코드인 한국의 제주도 전통에서 나무문으로 쓰인 정낭 정보통신의 뿌리를 소개하면서 AWGN 모델과 비슷한 정낭 결정 채널 모델을 조사하고, 채널 용량 분석에 접근하는 결정적 모델을 발견을 목표로 했다. 정낭 정보통신은 가족의 행방을 전달 위해 세 구멍으로 두 수직 돌에 3개의 서까래를 놓은 것으로 결정적인 신호였다. 본 논문에서는 선형 결정적 (linear deterministic) 신호에 대해 근사적(approximately)으로 결정적 신호처리의 채널 용량을 구한다.

DEVELOPMENT OF THE HANSEL-SPITTEL CONSTITUTIVE MODEL GAZED FROM A PROBABILISTIC PERSPECTIVE

  • LEE, KYUNGHOON;KIM, JI HOON;KANG, BEOM-SOO
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • 제21권3호
    • /
    • pp.155-165
    • /
    • 2017
  • The Hansel-Spittel constitutive model requires a total of nine parameters for flow stress prediction. Typically, the parameters are estimated by least squares methods for given tensile test measurements from a deterministic perspective. In this research we took a different approach, a probabilistic viewpoint, to see through the development of the Hansel-Spittel constitutive model. This perspective change showed that deterministic least squares methods are closely related to statistical maximum likelihood methods via Gaussian noise assumption. More intriguingly, this perspective shift revealed that the Hansel-Spittel constitutive model may leave out deterministic trends in residuals despite nearly perfect agreement with measurements. With tensile test measurements of AA1070 aluminum alloy, we demonstrated this deficiency of the Hansel-Spittel constitutive model, suggesting room for improvement.

Robust deterministic control for robotic manipulators with uncertainties

  • Kang, Chul-Goo;Horowitz, Roberto;Leitmann, George
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
    • /
    • pp.687-693
    • /
    • 1989
  • A robust deterministic control for a class of singularly perturbed uncertain systems, where uncertainties are characterized deterministically rather than stochastically, is developed based mainly on information available on an uncertain reduced-order system. The deterministic control scheme is applied to the motion control of a n degree of freedom robotic manipulator. The parasitic actuator and sensor dynamics of the manipulator are explicitly considered in the stability analysis of the deterministic controller using a singular perturbation model. Simulation and experimental studies for a two degree of freedom, direct drive SCARA manipulator are conducted to evaluate the effectiveness of the derived control scheme.

  • PDF

터널굴착시 지하수위저하에 의한 지표침하의 신뢰성 해석 (Reliability analysis of surface settlement by groundwater drawdown from tunnel excavation)

  • 장연수;김홍석;박정용;박준모;이성기
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
    • /
    • pp.1426-1433
    • /
    • 2005
  • In this paper, reliability analysis of surface settlement by ground water drawdown is performed using a reliability-groundwater flow numerical model. The result is compared with that of the deterministic model to evaluate the influence of the uncertainty from hydraulic conductivity in the soft ground as well as to determine the range of hydraulic conductivity of grouted ground. From the analyses, it was found that probability of failure to exceed the tolerable settlement was very high, if the hydraulic conductivity of grouted ground is decided from the deterministic flow model only. Reliability analysis which evaluates variance of hydraulic conductivity should be used together with the deterministic model for grouting design of tunnels to prevent ground water drawdown.

  • PDF

비가산성 잡음에서의 약한 화정적 신호의 검파방식에 관하여 (On a Detection Scheme for Weak Deterministic Signals in Non-Additive Noise)

  • Song, Iick-Ho
    • 대한전자공학회논문지
    • /
    • 제25권9호
    • /
    • pp.1019-1026
    • /
    • 1988
  • A parametric detection scheme for determenistic signals is obtained in a generalized observation model which contains non-additive noise. The model employed in this paper includes several special cases such as those describing purely-additive noise, multiplicative noise, and signal dependent noise and allows the consideration of deterministic and random signals. Locally optimum detectors for known deterministic signals in the model are derived and analyzed for performance. It is shown that the locally optimum detectors are interesting generalizations of those for the purely-additive noise model. Performance of the locally optimum detectors designed for the generalized observation model is compared to that of other common detectors.

  • PDF

베이지언 추론에 기반한 확률론적 피로수명 평가 (Stochastic Fatigue Life Assesment based on Bayesian-inference)

  • 박명진;김유일
    • 대한조선학회논문집
    • /
    • 제56권2호
    • /
    • pp.161-167
    • /
    • 2019
  • In general, fatigue analysis is performed by using deterministic model to estimate the optimal parameters. However, the deterministic model is difficult to clearly describe the physical phenomena of fatigue failure that contains many uncertainty factors. With regard to this, efforts have been made in this research to compare with the deterministic model and the stochastic models. Firstly, One deterministic S-N curve was derived from ordinary least squares technique and two P-S-N curves were estimated through Bayesian-linear regression model and Markov-Chain Monte Carlo simulation. Secondly, the distribution of Long-term fatigue damage and fatigue life were predicted by using the parameters obtained from the three methodologies and the long-term stress distribution.

시계열 데이터의 성격과 예측 모델의 예측력에 관한 연구 (Relationships Between the Characteristics of the Business Data Set and Forecasting Accuracy of Prediction models)

  • 이원하;최종욱
    • 지능정보연구
    • /
    • 제4권1호
    • /
    • pp.133-147
    • /
    • 1998
  • Recently, many researchers have been involved in finding deterministic equations which can accurately predict future event, based on chaotic theory, or fractal theory. The theory says that some events which seem very random but internally deterministic can be accurately predicted by fractal equations. In contrast to the conventional methods, such as AR model, MA, model, or ARIMA model, the fractal equation attempts to discover a deterministic order inherent in time series data set. In discovering deterministic order, researchers have found that neural networks are much more effective than the conventional statistical models. Even though prediction accuracy of the network can be different depending on the topological structure and modification of the algorithms, many researchers asserted that the neural network systems outperforms other systems, because of non-linear behaviour of the network models, mechanisms of massive parallel processing, generalization capability based on adaptive learning. However, recent survey shows that prediction accuracy of the forecasting models can be determined by the model structure and data structures. In the experiments based on actual economic data sets, it was found that the prediction accuracy of the neural network model is similar to the performance level of the conventional forecasting model. Especially, for the data set which is deterministically chaotic, the AR model, a conventional statistical model, was not significantly different from the MLP model, a neural network model. This result shows that the forecasting model. This result shows that the forecasting model a, pp.opriate to a prediction task should be selected based on characteristics of the time series data set. Analysis of the characteristics of the data set was performed by fractal analysis, measurement of Hurst index, and measurement of Lyapunov exponents. As a conclusion, a significant difference was not found in forecasting future events for the time series data which is deterministically chaotic, between a conventional forecasting model and a typical neural network model.

  • PDF

Reliability-Based Topology Optimization for Different Engineering Applications

  • Kharmanda, G.;Lambert, S.;Kourdi, N.;Daboul, A.;Elhami, A.
    • International Journal of CAD/CAM
    • /
    • 제7권1호
    • /
    • pp.61-69
    • /
    • 2007
  • The objective of this work is to integrate reliability analysis into topology optimization problems. We introduce the reliability constraint in the topology optimization formulation, and the new model is called Reliability-Based Topology Optimization (RBTO). The application of the RBTO model gives a different topology relative to the classical topology optimization that should be deterministic. When comparing the structures resulting from the deterministic topology optimization and from the RBTO model, the RBTO model yields structures that are more reliable than the deterministic ones (for the same weight). Several applications show the importance of this integration.

경로기반 해법알고리즘을 이용한 동적통행배분모형의 개발 (A ROUTE-BASED SOLUTION ALGORITHM FOR DYNAMIC USER EQUILIBRIUM ASSIGNMENT)

  • Sangjin Han
    • 대한교통학회:학술대회논문집
    • /
    • 대한교통학회 2002년도 제41회 학술발표회논문집
    • /
    • pp.97-139
    • /
    • 2002
  • The aim of the present study is to find a good quality user equilibrium assignments under time varying condition. For this purpose, this study introduces a dynamic network loading method that can maintain correct flow propagation as well as flow conservation, and it develops a novel solution algorithm that does not need evaluation of the objective function by modifying the Schittenhelm (1990)'s algorithm. This novel algorithm turns out to be efficient and convenient compared to the conventional Frank-Wolfe (1956) algorithm because the former finds solutions based on routes rather than links so that it can maintain correct flow propagation intrinsically in the time-varying network conditions. The application of dynamic user equilibrium (DUE) assignment model with this novel solution algorithm to test networks including medium-sized one shows that the present DUE assignment model gives rise to high quality discrete time solutions when we adopt the deterministic queuing model for a link performance function, and we associate flows and costs in a proper way.

  • PDF