Fariba Azizi

Alzahra University · Department of Mathematics

Maintenance has always been a crucial aspect of the manufacturing and industrial sectors. There is a recent surge of interest in utilizing advanced machine learning, and reinforcement learning models to enhance maintenance strategies. In this regard, this paper focuses on the development of a joint optimization model of maintenance and production f...

Given the deteriorative nature of industrial systems, implementation of advanced Preventive Maintenance (PM) strategies becomes of paramount importance to cope with the maintenance needs of ever-changing complex industrial and safety-critical systems. Conventionally, PM approaches are developed based on the perfect maintenance assumption, i.e., the...

Condition-based maintenance (CBM) has been emerged as a relatively new trend in maintenance management. Instead of conducting preventive maintenance actions in specified time intervals, the CBM program collects information through condition monitoring, then recommends maintenance actions based on the observed data. On the other hand, Bayesian contr...

This paper addresses a condition-based maintenance scheduling for a continuously monitored manufacturing system. In such a system, each unit is subject to deterioration, which is modeled as a continuous-time Markov process with two working states and a failure state. Maintenance is initiated when the system state falls into a state with a pre-speci...

It is widely recognized that there exists a close relationship between the health condition of manufacturing equipment and the overall quality of the manufactured product. It is, therefore, vital and of paramount practical importance and theoretical significance to develop optimized/integrated models of statistical process control (SPC) and mainten...

This paper addresses the estimation and optimization problems for a step-stress accelerated degradation test (SSADT) when a product’s degradation follows an inverse Gaussian (IG) process. Developing a link model to connect the deterioration measurements at different stress levels is a primary concern for this design issue. In this paper, we propose...

Competing risks arise when an individual is exposed to the several causes of failure. In this case, the recorded data includes two components, the failure times and the cause of failure indicators. Such data may suffer from censoring in the former part and missingness in the latter part. Prior researches have ignored the missing mechanism when anal...

In this paper, we discussed the estimation problem for the competing risks model when the data are progressive interval censored and follow Weibull distribution with an unknown common shape parameter. The parameters were estimated using both maximum likelihood and Bayesian methods and the Fisher information matrix was derived. The importance sampli...

In this paper, we propose a method to model the relationship between degradation and failure time for a simple step-stress test where the underlying degradation path is linear and different causes of failure are possible. It is assumed that the intensity function depends only on the degradation value. No assumptions are made about the distribution...

In this article, we consider the planning of simple step-stress life test in the presence of competing risks with the possibility of masked causes of failure and interval censoring. It is assumed that the competing risks have independent Weibull distribution with the common shape parameter, but different scale parameters and a tampered failure rate...