Reliability and maintenance modeling for dependent competing failure processes with shifting failure thresholds

TY - JOUR

T1 - Reliability and maintenance modeling for dependent competing failure processes with shifting failure thresholds

AU - Jiang, Lei

AU - Feng, Qianmei

AU - Coit, David W.

N1 - Funding Information: Manuscript received July 23, 2011; revised May 15, 2012; accepted July 26, 2012. Date of publication October 09, 2012; date of current version November 27, 2012. This research paper was based upon work supported by USA National Science Foundation (NSF) under Grants 0970140 and 0969423. Associate Editor: H. Li. L. Jiang and Q. Feng are with the Department of Industrial Engineering, University of Houston, Houston, TX 77004 USA. D. W. Coit is with the Department of Industrial and Systems Engineering, Rutgers University, Piscataway, NJ 08854 USA. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TR.2012.2221016

PY - 2012

Y1 - 2012

N2 - We present reliability and maintenance models for systems subject to multiple s-dependent competing failure processes with a changing, dependent failure threshold. In our model, two failure processes are considered: soft failure caused by continuous degradation together with additional abrupt degradation due to a shock process, and hard failure caused by the instantaneous stress from the same shock process. These two failure processes are correlated or s-dependent in two respects: 1) the arrival of each shock load affects both failure processes, and 2) the shock process impacts the hard failure threshold level. In previous research, the failure thresholds are fixed constants, which is appropriate for most design and reliability problems. However, the nature of the failure threshold has become a critical issue for certain classes of complex devices. When withstanding shocks, the system is deteriorating, and its resistance to failure is weakening. In this case, it becomes more sensitive to hard failure. In this paper, three cases of dependency between the shock process and the hard failure threshold level are studied. The first case is that the hard failure threshold value changes to a lower level when the first shock is recorded above a critical value, or a generalized extreme shock model. The second case is that the hard failure threshold value decreases to a lower level when the time lag between two sequential shocks is less than a threshold δ, or a generalized δ-shock model. The third case is that the hard failure threshold value reduces to a lower level right after m shocks whose magnitudes are larger than a critical value, or a generalized m-shock model. Based on degradation and random shock modeling, reliability models are developed for these two s-dependent failure processes with a shifting failure threshold. Two preventive maintenance policies are also applied and compared to decide which one is more beneficial. Then a Micro-Electro-Mechanical System example is given to demonstrate the reliability models and maintenance polices.

AB - We present reliability and maintenance models for systems subject to multiple s-dependent competing failure processes with a changing, dependent failure threshold. In our model, two failure processes are considered: soft failure caused by continuous degradation together with additional abrupt degradation due to a shock process, and hard failure caused by the instantaneous stress from the same shock process. These two failure processes are correlated or s-dependent in two respects: 1) the arrival of each shock load affects both failure processes, and 2) the shock process impacts the hard failure threshold level. In previous research, the failure thresholds are fixed constants, which is appropriate for most design and reliability problems. However, the nature of the failure threshold has become a critical issue for certain classes of complex devices. When withstanding shocks, the system is deteriorating, and its resistance to failure is weakening. In this case, it becomes more sensitive to hard failure. In this paper, three cases of dependency between the shock process and the hard failure threshold level are studied. The first case is that the hard failure threshold value changes to a lower level when the first shock is recorded above a critical value, or a generalized extreme shock model. The second case is that the hard failure threshold value decreases to a lower level when the time lag between two sequential shocks is less than a threshold δ, or a generalized δ-shock model. The third case is that the hard failure threshold value reduces to a lower level right after m shocks whose magnitudes are larger than a critical value, or a generalized m-shock model. Based on degradation and random shock modeling, reliability models are developed for these two s-dependent failure processes with a shifting failure threshold. Two preventive maintenance policies are also applied and compared to decide which one is more beneficial. Then a Micro-Electro-Mechanical System example is given to demonstrate the reliability models and maintenance polices.

KW - Age replacement policy

KW - block replacement policy

KW - degradation

KW - extreme shock model

KW - m-shock model

KW - multiple s-dependent competing failure processes

KW - δ-shock model

UR - http://www.scopus.com/inward/record.url?scp=84870544761&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84870544761&partnerID=8YFLogxK

U2 - 10.1109/TR.2012.2221016

DO - 10.1109/TR.2012.2221016

M3 - Article

SN - 0018-9529

VL - 61

SP - 932

EP - 948

JO - IEEE Transactions on Reliability

JF - IEEE Transactions on Reliability

IS - 4

M1 - 6327634

ER -