Reliability Evaluation for Mechanical Systems by Petri Nets

Mechanical systems is vulnerable to be influenced of its structure and human factors for its subsystems, components and the complex relationship between each unit, causing the mechanical systems to be failed, which severely affects the reliability of the mechanical systems. based on Petri nets models of mechanical systems analysis, from safety, intermediate and failure three aspects, 3-level working model of “safety-intermediate-failure” is introduced to reflect the reliability (functioning fully) of mechanical systems, intermediary transition between reliable and failure, failure (can not work). Through using the union and intersection operation of stochastic event, and considering the different values of the related failure parameters among basic events which impacts on the reliability of mechanical system, eventually the calculation of mechanical system reliability vector with the intermediate state is established.

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Task scheduling modelling and reliability evaluation of grid services using coloured Petri nets

Future Generation Computer Systems ◽

10.1016/j.future.2010.05.015 ◽

2010 ◽

Vol 26 (8) ◽

pp. 1141-1150 ◽

Cited By ~ 25

Author(s):

Mohammad Abdollahi Azgomi ◽

Reza Entezari-Maleki

Keyword(s):

Petri Nets ◽

Task Scheduling ◽

Reliability Evaluation ◽

Coloured Petri Nets ◽

Grid Services

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A NEW AND FAST ELECTRIC POWER GENERATING SYSTEM RELIABILITY EVALUATION MODEL USING PETRI NETS

International Journal of Reliability Quality and Safety Engineering ◽

10.1142/s0218539394000325 ◽

1994 ◽

Vol 01 (04) ◽

pp. 459-473 ◽

Cited By ~ 2

Author(s):

H. SALEHFAR ◽

R. RODICK

Keyword(s):

Monte Carlo ◽

Petri Nets ◽

System Reliability ◽

Random Number ◽

Evaluation Model ◽

Reliability Evaluation ◽

Power System Reliability ◽

General Sense ◽

Random Number Generators ◽

Generating System

This paper presents a new power generating system reliability evaluation model which performs like a Monte Carlo based reliability model but without using random number generators or probability distribution of system components. The proposed method is based on a class of Petri Nets known as timed state machine Petri Nets (TSMPNs). The method is simple, flexible, accurate, and extremely fast. A comparison of results from the new model with those from conventional Monte Carlo based reliability techniques shows the fidelity of the model and its potential usefulness in power system reliability studies. The method can also be extended and utilized for other system reliability studies in a more general sense.

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Mechanical systems and assemblies modeling using knowledge-intensive Petri nets formalisms

Artificial intelligence for engineering design analysis and manufacturing ◽

10.1017/s0890060401152066 ◽

2001 ◽

Vol 15 (2) ◽

pp. 145-171 ◽

Cited By ~ 11

Author(s):

X.F. ZHA ◽

H. DU

Keyword(s):

Petri Nets ◽

Design Process ◽

Mechanical Systems ◽

Object Oriented ◽

Hybrid Design ◽

Object Model ◽

Top Down ◽

Assembly Design ◽

Knowledge Based ◽

Knowledge Intensive

This paper presents a novel knowledge-based Petri net approach to mechanical systems and assemblies modeling within a design with objects environment. A new unified class of object-oriented knowledge Petri nets, which can incorporate a knowledge-based system with ordinary Petri nets, is defined and used for the unified representations of assembly design and modeling. The object knowledge Petri nets, as a graphical language and a new knowledge-based description scheme, can be used to express the qualitative and quantitative aspects of the assembly design and modeling process in an interactive and integrated way. The four-level hierarchy model is proposed and constructed in terms of function-behaviors, structures, geometries, and features. The function-behavior-structure description is built on more abstract concepts so that it can match well top-down design. The static and dynamic characteristics in the design of assembly can also be captured. With the help of fuzzy logic, the incomplete, imprecise knowledge and uncertainty in the design process can also be dealt with. Therefore, the hybrid design object model can incorporate product data model, top-down design process, and assembly process model using an object-oriented, knowledge-based, feature-based, parametric, and constraint-based modeling approach, and can provide a more accurate and more flexible representation. To verify and demonstrate the effective use of the proposed hybrid design object model, a prototype system has been developed. This research provides a knowledge-intensive framework for intelligent assembly design and modeling.

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