Optimal design of a series-parallel system with time-dependent reliability

1978 ◽  
Vol 17 (3) ◽  
pp. 354
Keyword(s):  
Optimal Design ◽  
Parallel System ◽  
Time Dependent

Optimal Design of a Series-Parallel System with Time-Dependent Reliability

1977 ◽  
Vol R-26 (2) ◽  
pp. 119-120 ◽  
Author(s):  
Kyoichi Nakashima ◽  
Kazuharu Yamato
Keyword(s):  
Optimal Design ◽  
Parallel System ◽  
Time Dependent

OPTIMAL DESIGN OF A MULTI-STATE WEIGHTED SERIES-PARALLEL SYSTEM USING PHYSICAL PROGRAMMING AND GENETIC ALGORITHMS

2011 ◽  
Vol 28 (04) ◽  
pp. 543-562 ◽  
Author(s):  
WEI LI ◽  
MING J. ZUO ◽  
RAMIN MOGHADDASS
Keyword(s):  
Optimal Design ◽  
Optimization Model ◽  
Parallel Systems ◽  
Optimization Method ◽  
Parallel System ◽  
System Model ◽  
System Cost ◽  
Physical Programming ◽  
Reliability Characteristics ◽  
Single Objective

In this paper, we report a study of the reliability optimal design of multi-state weighted series-parallel systems. Such a system and its components are capable of assuming a whole range of levels of performance, varying from perfect functioning to complete failure. There is a component utility corresponding to each component state. This system model is more general than the traditional binary series-parallel system model. The so-called component selection reliability optimal design problem which involves selection of components with known reliability characteristics and cost characteristics has been widely studied. However, the problem of determining system cost and system utility based on the relationships between component reliability, cost and utility has not been adequately addressed. We call it optimal component design reliability problem which has been studied in one of our former papers and continued in this paper for the multi-state weighted series-parallel systems. Furthermore, comparing to the traditional single-objective optimization model, the optimization model we proposed in this paper is a multi-objective optimization model which is used to maximize expected system performance utility and system reliability while minimizing investment system cost simultaneously. Genetic algorithm is used to solve the proposed physical programming based optimization model. An example is used to illustrate the flexibility and effectiveness of the proposed approach over the single-objective optimization method.

A Supply Network’s Optimal Information System and Material Flows

2013 ◽  
Vol 6 (3) ◽  
pp. 86-104 ◽  
Author(s):  
Frenck Waage
Keyword(s):  
Information System ◽  
Optimal Design ◽  
Time Dependent ◽  
Optimal Management ◽  
Supply Network ◽  
Material Flows ◽  
Facility Locations ◽  
Demand Pull ◽  
Optimal Network ◽  
Optimal Information

The management of a supply network is repeatedly forced to react to changes that have occurred, and to pro-act to changes that may occur. Management would certainly find it useful to have available a model which could identify the optimal re-action, or pro-action, from among all those which are possible. This paper will: (1) describe how such a model can be constructed in practice, and (2) how the model can be solved for the optimal management pro-actions, and reactions. The model describes all supply network interactions at any moment in time, and it describes all time dependent supply network interactions dynamically. The model serves as management’s optimal real-time decision support/information system. It will dynamically calculate the optimal operations policy for the entire supply network. The model is also capable of identifying: the optimal design of a supply network, the optimal capacities of a network, and the optimal network facility locations. It also solves some well known problems such as what is the optimal pure “demand – pull” policy in a network?

The number of failed components in series–parallel system and its application to optimal design

2020 ◽  
Vol 150 ◽  
pp. 106879
Author(s):  
Serkan Eryilmaz ◽  
Fatma Yerlikaya Özkurt ◽  
T. Erman Erkan
Keyword(s):  
Optimal Design ◽  
Parallel System ◽  
In Series

Optimal design of a commercial rubber isolator based on creep and creep-resistance analyses

2021 ◽  
pp. 095440622110171
Author(s):  
Dingxin Leng ◽  
Yi Yang ◽  
Demin Li ◽  
Yong Ma ◽  
Guijie Liu ◽  
...  
Keyword(s):  
Finite Element ◽  
Optimal Design ◽  
Constitutive Model ◽  
Creep Resistance ◽  
Time Dependent ◽  
Nonlinear Creep ◽  
Rubber Material ◽  
Creep Analysis ◽  
Creep Constitutive Model ◽  
Rubber Isolator

Creep is a common important physical phenomenon in rubber material, which induces the instability of geometrical dimension and deteriorates the mechanical performances. The present work develops an optimal design approach of a commercial rubber isolator based on creep analysis. First and foremost, a nonlinear creep constitutive model of rubber material is established, which can capture the hyper-elastic and time-dependent creep behaviors. Complete mechanical and creep tests of rubber materials are conducted, and material parameters are identified according to the experimental data. Then, the parametric finite element model of a rubber isolator is established, with which the time-dependent creep analysis based on the proposed creep constitutive model is conducted. The accuracy of the numerical creep analysis is validated at material level and structural component level. For engineering application, a sensitivity analysis and optimization design for creep-resistance of the rubber isolator is developed by combing finite element simulation and optimization method. The results show that creep-resistance characteristics of the optimal rubber isolator is largely improved, which provides a long-term stable behavior in vibration attenuation. The proposed method may provide an efficient tool for predicting the creep performance and optimal analysis of other commercial rubber-base products.

Optimal Heater Control in Thermoforming Preheating Using Approximate Function

2011 ◽  
Vol 314-316 ◽  
pp. 576-580
Author(s):  
Zhen Zhe Li ◽  
Gui Ying Shen ◽  
Mei Qin Li ◽  
Xiao Qian Wang ◽  
Yun De Shen
Keyword(s):  
Thermal Conductivity ◽  
Heat Flux ◽  
Optimal Design ◽  
Temperature Difference ◽  
Time Dependent ◽  
Function Form ◽  
Analysis Model ◽  
Order Polynomial ◽  
Approximate Function

Thermoforming is one of the most versatile and economical processes available for shaping polymer products. To improve the quality of final products, the temperature difference between surface and center of sheet should be continuously minimized. But, the temperature difference between surface and center of sheet can not be freely reduced because of low thermal conductivity of sheet materials. In this paper, an analysis model was developed under the condition that the inputted heat flux was expressed by an exponential function form. In the following step, an optimal design was carried out using a 3rd order polynomial. The optimal results show that the developed method can be used to reduce the temperature difference between surface and center of sheet by adjusting the parameter of time-dependent heat flux.

Time-dependent reliability and optimal design of scraper chains based on fretting wear process

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Shuai Li ◽  
Zhencai Zhu ◽  
Hao Lu ◽  
Gang Shen
Keyword(s):  
Optimal Design ◽  
Physical Model ◽  
Fretting Wear ◽  
Time Dependent ◽  
Dynamic Tension ◽  
Content Type ◽  
Dynamic Reliability ◽  
Wear Process ◽  
Scraper Conveyor ◽  
Wear Modes

Purpose This paper aims to present a dynamic reliability model of scraper chains based on the fretting wear process and propose a reasonable structural optimization method. Design/methodology/approach First, the dynamic tension of the scraper chain is modeled by considering the polygon effect of the scraper conveyor. Then, the numerical wear model of the scraper chain is established based on the tangential and radial fretting wear modes. The scraper chain wear process is introduced based on the diameter wear rate. Furthermore, the time-dependent reliability of scraper chains based on the fretting wear process is addressed by the third-moment saddlepoint approximation (TMSA) method. Finally, the scraper chain is optimized based on the reliability optimization design theory. Findings There is a correlation between the wear and the dynamic tension of the scraper conveyor. The unit sliding distance of fretting wear is affected by the dynamic tension of the scraper conveyor. The reliability estimation of the scraper chain with incomplete probability information is achieved by using the TMSA for the method needs only the first three statistical moments of the state variable. From the perspective of the chain drive system, the reliability-based optimal design of the scraper chain can effectively extend its service life and reduce its linear density. Originality/value The innovation of the work is that the physical model of the scraper chain wear is established based on the dynamic analysis of the scraper conveyor. And based on the physical model of wear, the time-dependent reliability and optimal design of scraper chains are carried out.

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