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Showing 2 results for Classification

Ehsanollah Habibi, Mina Salehi, Ali Taheri, Ghasem Yadegarfar,
Volume 5, Issue 4 (3-2018)
Abstract

Background: Recently adaptive neuro-fuzzy inference system is used for the classification of physical load based on three parameters including %HRmax, HRrest, and body weight. The aim of this study was to optimize this model to reduce the error and increase the accuracy of the model in the classification of physical load.
 Methods: The heart rate and oxygen consumption of 30 healthy men were measured during a step test in the laboratory. The VO2max of the participants was measured directly during a maximal treadmill test. A relationship was observed between the calculated %VO2max which is considered as the gold standard of physical load and the model inputs using ANFIS in MATLAB software version 8.0.0. the genetic algorithm was then applied as an optimization technique to the model.
Results: accuracy, sensitivity, and specificity of the model increased after optimization. The average of accuracy accelerated from 92.95% to 97.92%. The RMSE decreased from 5.4186 to 3.1882. Also, in %VO2max estimation, the maximum error of the mode was ±5% after optimization.
Conclusion: The results of this study show that the use of Genetic Algorithm during training process can increase the accuracy and decrease the error of ANFIS model in the estimation of%VO2max. . The advantages of this model include high precision, simplicity and applicability in real-world working environments and also interpersonal differences.

Amin Amiri Ebrahimabadi, Ahmad Soltanzadeh, Samira Ghiyasi,
Volume 8, Issue 1 (5-2020)
Abstract

Background and Aim: Occupational accidents are recognized as one of the major concerns in the mining industry. The purpose of this study was to analyze the incidence of occupational accidents in a mine for 10 years using Human Factor Analysis and Classification System (HFACS).
Method: This cross-sectional study was carried out on 664 mining accidents during 2009-2018. The tools used in this study included accident reporting checklists, human factors analysis and classification system (HFACS), and a team approach to analyze these accidents. Data analysis was performed using IBM SPSS AMOS v. 23.0.
Results: The accident frequency rate (AFR) was 15.10±3.34. The results of 10-years accident analysis in this mine based on HFACS model showed that the highest contribution of each parameter to the four layers including unsafe acts, preconditions for unsafe acts, unsafe supervision and organizational influences were respectively devoted to perceptual error (64.4%), Physical environment (29.5%), inadequate supervision (59.6%), and organizational process (65.6%). The results of structural equation modeling showed that the AFR is directly and indirectly affected by the layers of the HFACS model (P<0.05). The most significant impact on the AFR was related to the unsafe acts layer.
Conclusion: The findings of this study indicated that all four causal layers of human factors were effective in mine accidents, in addition the HFACS model is highly effective for unsafe acts-based accidents analysis, so it can be used for future planning to reduce accidents in the mining sector.



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