Application of Pareto optimization method for ontology matching in nuclear reactor domain

Enhanced efficiency of heavy-duty truck powertrains with constraints imposed on noise, vibration, and harshness requires novel solutions for torsion vibrations attenuation. In the paper, the weight-vibration Pareto optimization problem for a novel vibration absorber, a triple mass flywheel, for application in heavy-duty truck powertrains is considered. Global sensitivity analysis and Pareto optimization method are used to design a novel vibration absorber. The optimization method attempts to minimize oscillations of the torque at the transmission input shaft as well as to minimize total mass inertia of the absorber. It is shown that there exists a Pareto front between the measure of the attenuation of oscillations of the torque and the total mass inertia of a triple mass flywheel. The optimized design parameters for the absorber are obtained that provide the best attenuation of oscillations of the torque at the transmission input shaft for different mean values of the engine driving torque. The analysis shows real evidence of the feasibility of the application of this concept of vibration absorbers in heavy-duty truck powertrains. It is also shown that optimized design parameters of a triple mass flywheel put this concept in a superior position in comparison with a dual mass flywheel.

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A new optimization method based on cellular automata for VVER-1000 nuclear reactor loading pattern

Annals of Nuclear Energy ◽

10.1016/j.anucene.2008.12.029 ◽

2009 ◽

Vol 36 (5) ◽

pp. 659-667 ◽

Cited By ~ 20

Author(s):

Amir Hosein Fadaei ◽

Saeed Setayeshi

Keyword(s):

Cellular Automata ◽

Nuclear Reactor ◽

Optimization Method ◽

Loading Pattern

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Performance Optimization of a Diesel Engine with a Two-Stage Turbocharging System and Dual-Loop EGR Using Multi-Objective Pareto Optimization Based on Diesel Cycle Simulation

Energies ◽

10.3390/en12224223 ◽

2019 ◽

Vol 12 (22) ◽

pp. 4223 ◽

Cited By ~ 3

Author(s):

Heecheong Yoo ◽

Bum Park ◽

Honghyun Cho ◽

Jungsoo Park

Keyword(s):

Performance Optimization ◽

Fuel Efficiency ◽

Test Procedure ◽

Dilution Effect ◽

Optimization Method ◽

Pareto Optimization ◽

Design Parameters ◽

Cylinder Pressure ◽

Multi Objective ◽

Cycle Simulation

The effects of an electric supercharger (eS) and a dual-loop exhaust gas recirculation (EGR) system on a passenger car’s diesel engine’s emissions and fuel efficiency under various worldwide harmonized light-duty vehicles test procedure (WLTP) reference operation points were investigated using a one-dimensional engine cycle simulation, called GT-Power. After heavy EGR application, the in-cylinder pressure and temperature declined due to a dilution effect. As eS power and rpm increased, the brake-specific fuel consumption (BSFC) decreased because the effects of the air flow rate increased. However, it was unavoidable that nitrogen oxide (NOx) emissions also increased due to the higher in-cylinder pressure and temperature. To induce more EGR to the intake system, a dual-loop EGR system was applied with eS at different low-pressure EGR (LP-EGR) fractions (0, 0.25, 0.5, 0.75, and 1.0). Under these conditions, a design of experiment (DoE) procedure was carried out and response surface plots of the BSFC and brake-specific NOx (BSNOx) were prepared. A multi-objective Pareto optimization method was used to improve the trade-off in results between the BSFC and BSNOx. Through optimization, optimal Pareto fronts were obtained, which suggested design parameters for eS power and rpm to control the engine under various LP fraction conditions.

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Pareto-Based Bi-Objective Optimization Method of Sensor Placement in Structural Health Monitoring

Buildings ◽

10.3390/buildings11110549 ◽

2021 ◽

Vol 11 (11) ◽

pp. 549

Author(s):

Shaoxiao Nong ◽

Donghui Yang ◽

Tinghua Yi

Keyword(s):

Structural Health Monitoring ◽

Health Monitoring ◽

Sensor Placement ◽

Optimization Method ◽

Pareto Optimization ◽

Practical Significance ◽

Objective Functions ◽

Final Solution ◽

Structural Health ◽

Single Objective

For a practical structural health monitoring (SHM) system, the traditional single objective methods for optimal sensor placement (OSP) cannot always obtain the optimal result of sensor deployment without sacrificing other targets, which creates obstacles to the efficient use of the sensors. This study mainly focuses on establishing a bi-objective optimization method to select the sensor placement positions. The practical significance of several single-objective criteria for OSP is firstly discussed, based on which a novel bi-objective optimization method is proposed based on the Pareto optimization process, and the corresponding objective functions are established. Furthermore, the non-dominated sorting genetic algorithm is introduced to obtain a series of the Pareto optimal solutions, from which the final solution can be determined based on a new defined membership degree index. Finally, a numerical example of a plane truss is applied to illustrate the proposed method. The Pareto optimization-based bi-objective OSP framework presented in this study could be well suited for solving the problem of multi-objective OSP, which can effectively improve the efficiency of the limited sensors in SHM system.

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In situ TEM studies of irradiation effects for materials improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086568 ◽

1991 ◽

Vol 49 ◽

pp. 452-453

Author(s):

Charles W. Allen

Keyword(s):

Nuclear Reactor ◽

Austenitic Stainless Steels ◽

High Energy ◽

Point Of View ◽

In Situ Tem ◽

Irradiation Effects ◽

Tem Analysis ◽

Radiation Induced ◽

Analytical Tools

Irradiation effects studies employing TEMs as analytical tools have been conducted for almost as many years as materials people have done TEM, motivated largely by materials needs for nuclear reactor development. Such studies have focussed on the behavior both of nuclear fuels and of materials for other reactor components which are subjected to radiation-induced degradation. Especially in the 1950s and 60s, post-irradiation TEM analysis may have been coupled to in situ (in reactor or in pile) experiments (e.g., irradiation-induced creep experiments of austenitic stainless steels). Although necessary from a technological point of view, such experiments are difficult to instrument (measure strain dynamically, e.g.) and control (temperature, e.g.) and require months or even years to perform in a nuclear reactor or in a spallation neutron source. Consequently, methods were sought for simulation of neutroninduced radiation damage of materials, the simulations employing other forms of radiation; in the case of metals and alloys, high energy electrons and high energy ions.

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