Research On The Impact Of Heavy Machinery Industry Machine Shop Noise On The Cognitive Behavior Of Operators

As a source of pollution,noise can cause damage in humanity and human social activities.Monitoring and controlling noise now are the focus of both domestic and foreign researchers.Measurement of physiological indicators is one of the most commonly used methods.However,its sensitivity is low and it is difficult to be used in real-time measurement.Analysis of subjective annoyance is another popular method.However,it depends on individuals' feeling and that makes this method to be not objective.Compared to these methods,EEG method has high time resolution,good sensitivity and high reliability.In addition,the equipment of EEG is easy to carry.These advantages make EEG method become the direction of recent and future researches.This paper aims to use EEG method to measure the interference on operators' cognition behaviors caused by noise exposure in machine shops.Noise exposure in machine shops can lead to interference on operators' cognition behaviors and productivity reduction.This paper focuses on the noise effects and tries to give a reasonable EEG explanation.In order to properly simulate the working environment,the experiment used industrial noise which was acquired from a machine shop of a heavy industry enterprise.What's more,the cognitive experiment was designed to be a classification paradigm which consisted of tasks with different difficulties and task switches.By using a series of signal processing and feature extraction technologies like Event-related potentials(ERP)analysis,spectral analysis and complex brain networks analysis,combined with statistical analysis,ultimately we found out a series of characteristic amounts which can reflect the noise effect.They include the amplitude reduced N1,the amplitude increased P3b,the average power spectrum reduced alpha band and theta band,the average power spectrum increased beta band and a series of characteristic parameters reflecting the functional connection brain networks.Then the difficulty of cognitive tasks was regarded as a variable.A further analysis of the differences between the noise effects of different tasks with different difficulties was carried out.Finally,we found out that the more difficult of the task,the higher the possible that cognitive behavior was affected by noise will be.In addition,based on the characteristic amounts and characteristic parameters we found,another analysis of whether music rest can alleviate noise was carried out.By comparing same characteristic amounts and characteristic parameters before and after music rest,we found that the music rest can relieve noise interference.Furthermore,by comparing the differences between different tasks,we found that the same music rest were more effective on simple cognitive task.