scholarly journals An Technical Condition Evaluation Index Reduction Method Combining Rough Set and Genetic Algorithm

2021 ◽  
Vol 1043 (4) ◽  
pp. 042053
Author(s):  
S Wei ◽  
Q Zeng ◽  
Y Chen
Author(s):  
Liye Zhang ◽  
Yong He ◽  
Shoushan Cheng ◽  
Guoliang Wang ◽  
Hongwei Ren ◽  
...  

<p>With the number of bridges increases, the bridge health monitoring (BHM) technique is developing from single bridge monitoring to collaborative supervision of bridge group. Therefore, there are many technical problems need to be solved especially the performance evaluation index for bridge group network. This paper analyses the performance evaluation index of the bridges and bridge group network, establishes the performance evaluation index for bridge group based on rating factor (RF) and technical condition evaluation index. Based on bridge field testing and monitoring data, bridge technical condition evaluation index and performance evaluation method for bridge group are proposed. A case study demonstrates that the research results provide support for bridge group networking monitoring and collaborative supervision.</p>


2011 ◽  
Vol 243-249 ◽  
pp. 3087-3091
Author(s):  
Nian Ping Liu ◽  
Hong Tu Wang ◽  
Zhi Gang Yuan

Sand liquefaction is a problem of complex evolution of the disaster, there is no accurate way to judge at present, this study put forward an analytical method to improve and optimize the evaluation system of sand liquefaction based on rough set. The significance of indexes are confirmed by calculating rough dependability between indexes and result for appraisement, the result show that SPT blow count has the greatest impact on the evaluation system, the groundwater level has greater impact, followed by the sand depth, epicenteral distance and duration. The proposed approach overcame the subjectivity of traditional weight determination method, so it is more objective and accurate, and it is reasonable and effective to optimize the evaluation index of sand liquefaction.


Author(s):  
Ayaho Miyamoto

This paper describes an acquisitive method of rule‐type knowledge from the field inspection data on highway bridges. The proposed method is enhanced by introducing an improvement to a traditional data mining technique, i.e. applying the rough set theory to the traditional decision table reduction method. The new rough set theory approach helps in cases of exceptional and contradictory data, which in the traditional decision table reduction method are simply removed from analyses. Instead of automatically removing all apparently contradictory data cases, the proposed method determines whether the data really is contradictory and therefore must be removed or not. The method has been tested with real data on bridge members including girders and filled joints in bridges owned and managed by a highway corporation in Japan. There are, however, numerous inconsistent data in field data. A new method is therefore proposed to solve the problem of data loss. The new method reveals some generally unrecognized decision rules in addition to generally accepted knowledge. Finally, a computer program is developed to perform calculation routines, and some field inspection data on highway bridges is used to show the applicability of the proposed method.


2021 ◽  
Vol 2083 (4) ◽  
pp. 042005
Author(s):  
Xueyi Liu ◽  
Junhao Dong ◽  
Guangyu Tu

Abstract Fan, as the most commonly used mechanical equipment, is widely used. In order to solve the problem of fan bearing fault diagnosis, this paper analyzes the main factors affecting fan spindle speed and power generation in operation. The input and output parameters of the performance prediction model are determined. The performance prediction model of wind turbine is established by using generalized regression neural network, and the smoothing factor of GRNN is optimized by comparing the prediction accuracy of the model. Based on this model, the sliding data window method is used to calculate the residual evaluation index of wind turbine speed and power in real time. When the evaluation index continuously exceeds the pre-set threshold, the abnormal state of wind turbine can be judged. In order to obtain wind turbine blades with better aerodynamic performance, a blade aerodynamic performance optimization method based on quantum heredity is proposed. The B é zier curve control point is used as the design variable to represent the continuous chord length and torsion angle distribution of the blade, the blade shape optimization model aiming at the maximum power is established, and the quantum genetic algorithm is used to optimize the chord length and torsion angle of the blade under different constraints. The optimization results of quantum genetic algorithm and classical genetic algorithm are compared and analyzed. Under the same parameters and boundary conditions, the proposed blade aerodynamic optimization method based on quantum genetic optimization is better than the classical genetic optimization method, and can obtain better blade aerodynamic shape and higher wind energy capture efficiency. This method makes up for the shortcomings of traditional fault diagnosis methods, improves the recognition rate of fault types and the accuracy of fault diagnosis, and the diagnosis effect is good.


Sign in / Sign up

Export Citation Format

Share Document