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Michel Bruneau - One of the best experts on this subject based on the ideXlab platform.

  • seismic performance of steel plate shear walls considering two different design philosophies of infill plates i Deterioration Model development
    Journal of Structural Engineering-asce, 2015
    Co-Authors: Ronny Purba, Michel Bruneau
    Abstract:

    AbstractResearch was conducted to investigate the seismic performance of steel plate shear walls (SPSWs) having infill plates designed to resist different percentages of the applied lateral loads. The FEMA P695 methodology, which defines the performance in terms of collapse potential under maximum considered earthquake (MCE) ground motions, was used to compare the performance of the SPSWs under consideration. This paper describes the development of component strength Deterioration Models that are needed to perform the collapse assessment of SPSWs, focusing on stress-strain or force-deformation relationships for infill plates and boundary elements. The approach began with identifying the Deterioration and failures modes of SPSW from 36 tested specimens. Cyclic deformation capacities of these SPSWs when reaching their ultimate strength, failure points, and rates of degradation were statistically quantified. Based on these statistical results, initial Deterioration Models for SPSW components were developed i...

Fran H Norris - One of the best experts on this subject based on the ideXlab platform.

  • a test of the social support Deterioration Model in the context of natural disaster
    Journal of Personality and Social Psychology, 1993
    Co-Authors: Krzysztof Kaniasty, Fran H Norris
    Abstract:

    This prospective longitudinal study examined stress-mediating potentials of 3 types of social support: social embeddedness, perceived support from nonkin, and perceived support from kin. As participants in a statewide panel study, 222 older adults were interviewed once before and twice after a severe flood. It was hypothesized that disaster exposure (stress) would influence depression directly and indirectly, through Deterioration of social support. LISREL analyses indicated that postdisaster declines in social embeddedness and nonkin support mediated the immediate and delayed impact of disaster stress. No evidence was found for the mediational role of kin support. Findings are in accord with conceptualizations of social support as an entity reflecting dynamic transactions among individuals, their social networks, and environmental pressures. Language: en

Ronny Purba - One of the best experts on this subject based on the ideXlab platform.

  • seismic performance of steel plate shear walls considering two different design philosophies of infill plates i Deterioration Model development
    Journal of Structural Engineering-asce, 2015
    Co-Authors: Ronny Purba, Michel Bruneau
    Abstract:

    AbstractResearch was conducted to investigate the seismic performance of steel plate shear walls (SPSWs) having infill plates designed to resist different percentages of the applied lateral loads. The FEMA P695 methodology, which defines the performance in terms of collapse potential under maximum considered earthquake (MCE) ground motions, was used to compare the performance of the SPSWs under consideration. This paper describes the development of component strength Deterioration Models that are needed to perform the collapse assessment of SPSWs, focusing on stress-strain or force-deformation relationships for infill plates and boundary elements. The approach began with identifying the Deterioration and failures modes of SPSW from 36 tested specimens. Cyclic deformation capacities of these SPSWs when reaching their ultimate strength, failure points, and rates of degradation were statistically quantified. Based on these statistical results, initial Deterioration Models for SPSW components were developed i...

Krzysztof Kaniasty - One of the best experts on this subject based on the ideXlab platform.

  • a test of the social support Deterioration Model in the context of natural disaster
    Journal of Personality and Social Psychology, 1993
    Co-Authors: Krzysztof Kaniasty, Fran H Norris
    Abstract:

    This prospective longitudinal study examined stress-mediating potentials of 3 types of social support: social embeddedness, perceived support from nonkin, and perceived support from kin. As participants in a statewide panel study, 222 older adults were interviewed once before and twice after a severe flood. It was hypothesized that disaster exposure (stress) would influence depression directly and indirectly, through Deterioration of social support. LISREL analyses indicated that postdisaster declines in social embeddedness and nonkin support mediated the immediate and delayed impact of disaster stress. No evidence was found for the mediational role of kin support. Findings are in accord with conceptualizations of social support as an entity reflecting dynamic transactions among individuals, their social networks, and environmental pressures. Language: en

Mitra Fouladirad - One of the best experts on this subject based on the ideXlab platform.

  • Prognostics for non-monotonous health indicator data with jump diffusion process
    Computers and Industrial Engineering, 2018
    Co-Authors: Houda Ghamlouch, Mitra Fouladirad, Antoine Grall
    Abstract:

    For the very first time a jump diffusion process with Markovian covariates is used for prognostics and health monitoring. This paper aims to give a methodology for reliability and lifetime estimation of a non-increasing, deteriorating system where the increments are not normally distributed and the Wiener process cannot be used. We propose, first to study of the statistical properties of increments. Afterward the measures dependency is tested. A jump diffusion process with a covariate is considered to fit the Deterioration Model. The covariate Models the environmental conditions. The proposed Deterioration Model is applied to a large set of collected data corresponding to the health indicators in ageing components in hydraulic electrical production systems and prognostic results are given.

  • A pitch control system Deterioration Model considering wind speed turbulence intensity
    2018
    Co-Authors: Mitra Fouladirad, Antoine Grall
    Abstract:

    As a consequence of high failure rate occurring to wind turbines (WTs), more and more asset owners begin to pay attention to WT’s maintenance planning. To implement an efficient condition-based maintenance policy, the Deterioration Modeling is of primary importance. The inherence character of wind makes WT’s operation full of uncertainties, hence, the pitch actuator movement is random and it can be Modeled by a stochastic process. Meanwhile, the Deterioration of the pitch control system related to the usage of the actuator is random. When the wind speed is higher than the rated wind speed (a design WT parameter, when wind speed is higher than the rated wind speed, the pitch system begin to operate) and the wind speed turbulence intensity (TI) is very important, the Deterioration rate of the pitch control system increases significantly. For instance the pitch system has more failures in a windy season. Therefore, in order to propose an appropriate maintenance policy for pitch control system, it is more sensible to take into account the influence of wind speed in Deterioration Modelling. In this paper, we focus on the Deterioration of hydraulic pitch control system. After studying the factors influencing the Deterioration, a stochastic process considering wind speed as covariates is used to Model the Deterioration. A maintenance policy based on an alarm threshold is considered.

  • Model selection for degradation Modeling and prognosis with health monitoring data
    Reliability Engineering and System Safety, 2018
    Co-Authors: Thi Phuong Khanh Nguyen, Mitra Fouladirad, Antoine Grall
    Abstract:

    Health monitoring data are increasingly collected and widely used for reliability assessment and lifetime pre- diction. They not only provide information about degradation state but also could trace failure mechanisms of assets. The selection of a Deterioration Model that optimally fits in with health monitoring data is an important issue. It can enable a more precise asset health prognostic and help reducing operation and maintenance costs. Therefore, this paper aims to address the problem of degradation Model selection including goals, procedure and evaluation criteria. Focusing on continuous degradation Modeling including some currently used Lévy processes, the performance of classical and prognostic criteria are discussed through numerous numerical examples. We also investigate in what circumstances which methods perform better than others. The efficiency of a new hybrid criterion is highlighted that allows to take into account the information of goodness-of-fit of observation data when evaluating prognostic measure.

  • condition based maintenance policies for a combined wear and shock Deterioration Model with covariates
    Computers & Industrial Engineering, 2015
    Co-Authors: Wenjin Zhu, Mitra Fouladirad, Christophe Berenguer
    Abstract:

    We propose a Deterioration Model considering both wear and shock with covariate.We give the analytical formulas for Deterioration evaluation and cost calculation.We simulate and analyze the application scope of the different maintenance policies.We make a sensitivity analysis of the parameters of the optimal maintenance policy. This paper proposes a Deterioration Model which considers two mechanisms of system Deterioration: wear and shock, both affected by environmental conditions. The Deterioration is Modeled by the sum of wear and cumulative shocks, where the wear damage is Modeled by a non-stationary Gamma process and the random shock damage is Modeled by a generalized Pareto distribution satisfying Poisson arrivals. The effect of the environment on the mean Deterioration rate is Modeled by covariates via the Cox proportional hazards Model. Both preventive and corrective replacement will be considered according to the results of system-state inspections. Based on partial inspection information, the so-called wear-oriented and shock-oriented maintenance policies are proposed specially for the different Deterioration sources. The performance of these maintenance policies are studied through numerical implementations and compared with the policies which use complete inspection information. The optimal maintenance policy leading to the minimal cost criterion is obtained and limitation of the use of these policies is discussed.

  • Condition-based maintenance policies for a combined wear and shock Deterioration Model with covariates
    Computers and Industrial Engineering, 2015
    Co-Authors: Wenjin Zhu, Mitra Fouladirad, Christophe Berenguer
    Abstract:

    This paper proposes a Deterioration Model which considers two mechanisms of system Deterioration: wear and shock, both affected by environmental conditions. The Deterioration is Modeled by the sum of wear and cumulative shocks, where the wear damage is Modeled by a non-stationary Gamma process and the random shock damage is Modeled by a generalized Pareto distribution satisfying Poisson arrivals. The effect of the environment on the mean Deterioration rate is Modeled by covariates via the Cox proportional hazards Model. Both preventive and corrective replacement will be considered according to the results of system-state inspections. Based on partial inspection information, the so-called wear-oriented and shock-oriented maintenance policies are proposed specially for the different Deterioration sources. The performance of these maintenance policies are studied through numerical implementations and compared with the policies which use complete inspection information. The optimal maintenance policy leading to the minimal cost criterion is obtained and limitation of the use of these policies is discussed