目的探讨工厂噪音对听力损失的调查及相关行为干预效果评估与对策。方法选取2017年1月—2019年12月本市某工厂在岗噪音作业人员90名作为研究对象,对在岗噪音作业人员的听力损伤状况进行调查,统计听力损失检出率,并采取相关干预措施,评...目的探讨工厂噪音对听力损失的调查及相关行为干预效果评估与对策。方法选取2017年1月—2019年12月本市某工厂在岗噪音作业人员90名作为研究对象,对在岗噪音作业人员的听力损伤状况进行调查,统计听力损失检出率,并采取相关干预措施,评估相关干预效果。同时分析听力损失与工龄、年龄、噪音强度的关系,制定相关对策。结果90名员工听力损失检出率为22.22%。经过干预和临床治疗后,总有效率为85.00%。1~5年、6~10年、>10年工龄听力损失检出率分别为9.52%、14.29%、38.24%,差异有统计学意义(P<0.05)。<30岁、30~40岁、>50岁年龄听力损失检出率分别为4.00%、26.67%、31.43%,差异有统计学意义(P<0.05)。<80 d B、80~90 d B、>90 d B噪音强度听力损失检出率分别为11.43%、24.00%、40.00%,差异有统计学意义(P<0.05)。结论在岗噪音作业人员听力损失检出率与年龄、工龄、噪音强度有关,应加强员工的自我防范意识,提高企业重视程度,保证员工健康。展开更多
A machine learning based speech enhancement method is proposed to improve the intelligibility of whispered speech. A binary mask estimated by a two-class support vector machine （SVM） classifier is used to synthesize...A machine learning based speech enhancement method is proposed to improve the intelligibility of whispered speech. A binary mask estimated by a two-class support vector machine （SVM） classifier is used to synthesize the enhanced whisper. A novel noise robust feature called Gammatone feature cosine coefficients （GFCCs） extracted by an auditory periphery model is derived and used for the binary mask estimation. The intelligibility performance of the proposed method is evaluated and compared with the traditional speech enhancement methods. Objective and subjective evaluation results indicate that the proposed method can effectively improve the intelligibility of whispered speech which is contaminated by noise. Compared with the power subtract algorithm and the log-MMSE algorithm, both of which do not improve the intelligibility in lower signal-to-noise ratio （SNR） environments, the proposed method has good performance in improving the intelligibility of noisy whisper. Additionally, the intelligibility of the enhanced whispered speech using the proposed method also outperforms that of the corresponding unprocessed noisy whispered speech.展开更多
Defining the quantity K as the signal-to-noise ratio （SNR） and the normalized intensity fluctuation C（O） of a single-mode laser for bias signal modulation driven by color noises with colored correlation, the whole...Defining the quantity K as the signal-to-noise ratio （SNR） and the normalized intensity fluctuation C（O） of a single-mode laser for bias signal modulation driven by color noises with colored correlation, the whole output properties of the laser system is described by K. It is found that there is a maximum in the curves of K versus D, Q, and io. The optimization parameters are gained.展开更多
Effects of noise on rate oscillations during CO oxidation on Pt（110） surface were investigated, both theoretically and numerically, by focusing on the interplay of internal noise （IN） due to stochasticity in react...Effects of noise on rate oscillations during CO oxidation on Pt（110） surface were investigated, both theoretically and numerically, by focusing on the interplay of internal noise （IN） due to stochasticity in reaction events, and external noise （EN） resulting from parameter perturbation. The surface is divided into cells of variable size which are assumed to be well mixed, and we consider the behavior inside a single cell. Attention is paid to parameter regions subthreshold of the deterministic Hopf bifurcation, where noise can induce stochastic oscillations, the signal-to-noise ratio （SNR） of which shows a maximum with the variation of noise intensity, known as coherent resonance （CR）. By stochastic normal theory, we show that IN and EN contribute in a weighted additive way to an effective noise that lead to CR, such that SNR shows a ridge shape in the D-1/√N plane, where D and 1/√N measures the strength of EN and IN, respectively. It is shown that for too large IN （EN）, CR behavior with EN （IN） no longer exists. Numerical simulations show good agreements with the theoretical results.展开更多
There has been a lot of research has been performed regarding diagnosing rolling element bearing faults using wavelet analysis, but almost all methods are not ideal for picking up fault signal characteristics under st...There has been a lot of research has been performed regarding diagnosing rolling element bearing faults using wavelet analysis, but almost all methods are not ideal for picking up fault signal characteristics under strong noise. Therefore, this paper proposes auto-correlation, cross-correlation and weighted average fault diagnosis methods based on wavelet transform (WT) de-noising which combine correlation analysis with WT for the first time. These three methods compute the auto-correlation, the cross-correlation and the weighted average of the measured vibration signals, then de-noise by thresholding and computing the auto-correlation of de-noised coefficients of WT and FFT of energy sequence. The simulation results indicate that all methods enhance the capabilities of fault diagnosis of rolling bearings and pick up the fault characteristics effectively.展开更多
文摘目的探讨工厂噪音对听力损失的调查及相关行为干预效果评估与对策。方法选取2017年1月—2019年12月本市某工厂在岗噪音作业人员90名作为研究对象,对在岗噪音作业人员的听力损伤状况进行调查,统计听力损失检出率,并采取相关干预措施,评估相关干预效果。同时分析听力损失与工龄、年龄、噪音强度的关系,制定相关对策。结果90名员工听力损失检出率为22.22%。经过干预和临床治疗后,总有效率为85.00%。1~5年、6~10年、>10年工龄听力损失检出率分别为9.52%、14.29%、38.24%,差异有统计学意义(P<0.05)。<30岁、30~40岁、>50岁年龄听力损失检出率分别为4.00%、26.67%、31.43%,差异有统计学意义(P<0.05)。<80 d B、80~90 d B、>90 d B噪音强度听力损失检出率分别为11.43%、24.00%、40.00%,差异有统计学意义(P<0.05)。结论在岗噪音作业人员听力损失检出率与年龄、工龄、噪音强度有关,应加强员工的自我防范意识,提高企业重视程度,保证员工健康。
基金The National Natural Science Foundation of China (No.61231002,61273266,51075068,60872073,60975017, 61003131)the Ph.D.Programs Foundation of the Ministry of Education of China(No.20110092130004)+1 种基金the Science Foundation for Young Talents in the Educational Committee of Anhui Province(No. 2010SQRL018)the 211 Project of Anhui University(No.2009QN027B)
文摘A machine learning based speech enhancement method is proposed to improve the intelligibility of whispered speech. A binary mask estimated by a two-class support vector machine （SVM） classifier is used to synthesize the enhanced whisper. A novel noise robust feature called Gammatone feature cosine coefficients （GFCCs） extracted by an auditory periphery model is derived and used for the binary mask estimation. The intelligibility performance of the proposed method is evaluated and compared with the traditional speech enhancement methods. Objective and subjective evaluation results indicate that the proposed method can effectively improve the intelligibility of whispered speech which is contaminated by noise. Compared with the power subtract algorithm and the log-MMSE algorithm, both of which do not improve the intelligibility in lower signal-to-noise ratio （SNR） environments, the proposed method has good performance in improving the intelligibility of noisy whisper. Additionally, the intelligibility of the enhanced whispered speech using the proposed method also outperforms that of the corresponding unprocessed noisy whispered speech.
基金Key Project of Education Bureau of Hubei Province of China
文摘Defining the quantity K as the signal-to-noise ratio （SNR） and the normalized intensity fluctuation C（O） of a single-mode laser for bias signal modulation driven by color noises with colored correlation, the whole output properties of the laser system is described by K. It is found that there is a maximum in the curves of K versus D, Q, and io. The optimization parameters are gained.
文摘Effects of noise on rate oscillations during CO oxidation on Pt（110） surface were investigated, both theoretically and numerically, by focusing on the interplay of internal noise （IN） due to stochasticity in reaction events, and external noise （EN） resulting from parameter perturbation. The surface is divided into cells of variable size which are assumed to be well mixed, and we consider the behavior inside a single cell. Attention is paid to parameter regions subthreshold of the deterministic Hopf bifurcation, where noise can induce stochastic oscillations, the signal-to-noise ratio （SNR） of which shows a maximum with the variation of noise intensity, known as coherent resonance （CR）. By stochastic normal theory, we show that IN and EN contribute in a weighted additive way to an effective noise that lead to CR, such that SNR shows a ridge shape in the D-1/√N plane, where D and 1/√N measures the strength of EN and IN, respectively. It is shown that for too large IN （EN）, CR behavior with EN （IN） no longer exists. Numerical simulations show good agreements with the theoretical results.
文摘There has been a lot of research has been performed regarding diagnosing rolling element bearing faults using wavelet analysis, but almost all methods are not ideal for picking up fault signal characteristics under strong noise. Therefore, this paper proposes auto-correlation, cross-correlation and weighted average fault diagnosis methods based on wavelet transform (WT) de-noising which combine correlation analysis with WT for the first time. These three methods compute the auto-correlation, the cross-correlation and the weighted average of the measured vibration signals, then de-noise by thresholding and computing the auto-correlation of de-noised coefficients of WT and FFT of energy sequence. The simulation results indicate that all methods enhance the capabilities of fault diagnosis of rolling bearings and pick up the fault characteristics effectively.
