Functional and dysfunctional analysis of a safety instrumented system (SIS) through the common cause failures (CCFs) assessment. Case of high integrity protection pressure system (HIPPS)

2022 ◽  
Author(s):  
H. Metatla ◽  
M. Rouainia
Keyword(s):  
Pressure System ◽  
Common Cause ◽  
Integrity Protection ◽  
Common Cause Failures ◽  
The Common ◽  
High Integrity

Common cause failure model updating for risk monitoring in nuclear power plants based on alpha factor model

2017 ◽  
Vol 231 (3) ◽  
pp. 209-220 ◽  
Author(s):  
Min Zhang ◽  
Zhijian Zhang ◽  
Ali Mosleh ◽  
Sijuan Chen
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Model Updating ◽  
Factor Model ◽  
Failure Model ◽  
Common Cause ◽  
Common Cause Failure ◽  
Risk Monitoring ◽  
Common Cause Failures ◽  
The Common

Common cause failure model updating (both qualitatively and quantitatively) is a key factor in risk monitoring for nuclear power plants when configuration changes (e.g. components become unavailable) occur among a redundant configuration. This research focuses on the common cause failure updating based on the alpha factor model method, which is commonly used in the living probabilistic safety assessment models for nuclear power plant risk monitoring. This article first discusses the common cause failure model updating in an ideal condition, which evaluates the common cause failure model parameters for the configurationally changed system in different ways, based on the causes of the detected failures. Then, two alternative updating processes are proposed considering the difficulty to identify failure causes immediately during plant operation: one is to update the common cause failure models with the assumption that the failures detected are independent failures and the other is to update the common cause failure models with the parameters as expectations of the values for all possible failure causes. Finally, a case study is given to illustrate the common cause failure updating process and to compare these two alternative processes. The results show that (1) common cause failures can be reevaluated automatically by the methods proposed in this article and (2) the second process is more conservative and reasonable but with more data requirements compared with the first approach. Considering limitations in accessibility of the data, the first strategy is suggested currently. More future work on data acquisition is demanded for better assessment of common cause failures during nuclear power plant risk monitoring.

scholarly journals Survival Signature-based Reliability Approach for Complex Systems Susceptible to Common Cause Failures

2019 ◽  
Vol 26 (03) ◽  
pp. 1950013
Author(s):  
Geng Feng
Keyword(s):  
Complex Systems ◽  
Reliability Analysis ◽  
Factor Model ◽  
Limited Data ◽  
Common Cause ◽  
Practical Applications ◽  
Overall Stability ◽  
Common Cause Failures ◽  
The Common ◽  
Multiple Component

The importance of reliability to complex systems cannot be disputed as they are the backbones of our society. In practice, the common cause failures may have severe reverse function on complex systems’ overall stability. Survival Signature opens a new way to perform reliability analysis on systems with multiple component types. This paper under takes a research on survival signature-based reliability analysis on complex systems susceptible to Common Cause Failures. To be specific, it proposes the standard [Formula: see text]-factor model and general [Formula: see text]-factor model to combine with the survival signature. In practical applications, the [Formula: see text]-factor estimator of the system might not be defined completely due to limited data, or knowledge which requires to take imprecision into account. Some numerical cases are presented to show the applicability of the methods for complex systems. In addition, this paper may attract people’s attention on the conception of Design for Reliability.

scholarly journals Assessment of the Common Cause Failure(CCFs) effect on Safety Instrumented System(SIS) by usign the Fault Tree Analysis (FTA) method

2020 ◽  
Vol 5 (2) ◽  
pp. 118-129
Author(s):  
Hassina Metatla ◽  
Mounira Rouainia
Keyword(s):  
Factor Model ◽  
Fault Tree ◽  
Fault Tree Analysis ◽  
International Electrotechnical Commission ◽  
Tree Analysis ◽  
Common Cause ◽  
Common Cause Failure ◽  
Common Cause Failures ◽  
The Common ◽  
Negative Impacts

The reliability of the safety-instrumented system (SIS) has received a lot of attention during the past decade, with the emergence of the new standards such as International Electrotechnical Commission IEC61508, and IEC61511, that provides a general framework for the design and implementation of these safety barriers. Among the problems influencing on the global SIS reliability: Common Cause Failure (CCF), which contributes too many accidents, that has a negative impacts, so it must be considered in the risk and reliability assessment for these systems. The aim of this work is to focus on the effects of common cause failures (CCFs) on the reliability of a SIS, by implementing a comparative SIS dependability study with and without consideration the CCFs, using the beta factor model, and the fault tree analysis (FTA) method.

A NEW APPROACH FOR RELIABILITY ESTIMATION OF SYSTEMS WITH COMPLEX COMMON CAUSE FAILURES

1994 ◽  
Vol 01 (02) ◽  
pp. 291-298 ◽  
Author(s):  
ZHIJIE PAN ◽  
YASUO NONAKA
Keyword(s):  
Aging Process ◽  
Reliability Estimation ◽  
System Component ◽  
Stress Model ◽  
New Approach ◽  
Common Cause ◽  
Common Cause Failure ◽  
Common Cause Failures ◽  
The Common ◽  
Mutually Independent

This paper presents a new concept, complex common cause failure, for common cause failure analysis. A common stress model is developed, in which the common cause events are described as common stresses that will affect directly and simultaneously on the internal aging process of each system component and further change their failure probabilities, while the internal aging processes of components are still considered mutually independent. The common stress model can be used to estimate the reliability of systems with complex common cause failures.

The Principle of the Common Cause

2009 ◽  
Author(s):  
Gabor Hofer-Szabo ◽  
Miklos Redei ◽  
Laszlo E. Szabo
Keyword(s):  
Common Cause ◽  
The Common

scholarly journals Clinical Profile of Acute Poisoning in Children at a Teaching Hospital in Lalitpur

2014 ◽  
Vol 34 (2) ◽  
pp. 100-103 ◽  
Author(s):  
Ajaya Kumar Dhakal ◽  
D Shrestha ◽  
A Shakya ◽  
SC Shah ◽  
H Shakya
Keyword(s):  
Teaching Hospital ◽  
Hospital Admissions ◽  
Acute Poisoning ◽  
Childhood Mortality ◽  
Age Group ◽  
Common Cause ◽  
Mortality And Morbidity ◽  
History Of ◽  
The Common ◽  
Poisoning In Children

Introduction: Acute poisonings are one of the common cause of emergency visits and hospital admissions and is potentially preventable cause of childhood mortality and morbidity. The objectives of this study were to identify the common type of poisoning in children, to determine types of poisoning according to age and to find out the common age group in which the incidence of poisoning was high.Materials and Methods: It was a descriptive observational study done in a teaching hospital in Lalitpur, Nepal in patients aged 1 month to 18 years who visited the emergency department and were admitted to hospital with history of alleged poisoning from 2009 July to 2014 January.Results: Fifty patients were included. Drugs, kerosene and organophosphorus were most common cause of poisoning. Drugs and kerosene below 10 years of age and organophosphorus and drugs above 10 years of age were common types of poisoning. Maximum numbers (50%) of children with poisoning cases were below five year of age. Mean duration of hospital stay was 2.1days and mean age of poisoning was 7.8 years with a male(54%) predominance. Majority of poisoning occurred at home (84%) and 68% of patients were symptomatic at presentation to hospital with 84% of patients presenting to hospital within six hours.Conclusion: This study showed that drugs, kerosene and organophosphorus were most common forms of poisoning. Young children were most vulnerable for acute poisoning.DOI: http://dx.doi.org/10.3126/jnps.v34i2.10139J Nepal Paediatr Soc 2014;34(2):100-103 

An overview of proximal suspensory ligament desmitis

UK-Vet Equine ◽  
2019 ◽  
Vol 3 (5) ◽  
pp. 175-181
Author(s):  
Jonathan Anderson
Keyword(s):  
Treatment Options ◽  
Poor Performance ◽  
Diagnostic Techniques ◽  
Common Cause ◽  
Suspensory Ligament ◽  
The Common ◽  
Hindlimb Lameness

Proximal suspensory disease is a common cause of both forelimb and hindlimb lameness and poor performance in the horse. The following article describes the common presentations, diagnostic techniques and treatment options for the condition in both the forelimbs and the hindlimbs.

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