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The relationship between age,acceptable noise level,and listening effort in middle-aged and older-aged individuals
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作者 Hemanth Narayan Shetty Suma Raju Sanjana Singh S 《Journal of Otology》 CAS CSCD 2023年第4期220-229,共10页
Objective:The purpose of the study was to evaluate listening effort in adults who experience varied annoyance towards noise.Materials and methods:Fifty native Kannada-speaking adults aged 41e68 years participated.We e... Objective:The purpose of the study was to evaluate listening effort in adults who experience varied annoyance towards noise.Materials and methods:Fifty native Kannada-speaking adults aged 41e68 years participated.We evaluated the participant's acceptable noise level while listening to speech.Further,a sentence-final wordidentification and recall test at 0 dB SNR(less favorable condition)and 4 dB SNR(relatively favorable condition)was used to assess listening effort.The repeat and recall scores were obtained for each condition.Results:The regression model revealed that the listening effort increased by 0.6%at 0 dB SNR and by 0.5%at 4 dB SNR with every one-year advancement in age.Listening effort increased by 0.9%at 0 dB SNR and by 0.7%at 4 dB SNR with every one dB change in the value of Acceptable Noise Level(ANL).At 0 dB SNR and 4 dB SNR,a moderate and mild negative correlation was noted respectively between listening effort and annoyance towards noise when the factor age was controlled.Conclusion:Listening effort increases with age,and its effect is more in less favorable than in relatively favorable conditions.However,if the annoyance towards noise was controlled,the impact of age on listening effort was reduced.Listening effort correlated with the level of annoyance once the age effect was controlled.Furthermore,the listening effort was predicted from the ANL to a moderate degree. 展开更多
关键词 Listening effort Acceptable noise level Cognitive reservoir Repeat and recall task
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Pixel and Column Fixed Pattern Noise Suppression Mechanism in CMOS Image Sensor 被引量:5
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作者 徐江涛 姚素英 李斌桥 《Transactions of Tianjin University》 EI CAS 2006年第6期442-445,共4页
A double sampling circuit to eliminating fixed pattern noise(FPN) in CMOS image sensor (CIS) is presented. Double sampling is implemented by column switch capacitor amplifier directly, and offset compensation is added... A double sampling circuit to eliminating fixed pattern noise(FPN) in CMOS image sensor (CIS) is presented. Double sampling is implemented by column switch capacitor amplifier directly, and offset compensation is added to the amplifier to suppress column FPN. The amplifier is embedded in a 64×64 CIS and successfully fabricated with chartered 0.35 μm process. Theory analysis and circuit simulation indicate that FPN can be suppressed from millivolt to microvolt. Test results show that FPN is smaller than one least-significant bit of 8 bit ADC. FPN is reduced to an acceptable level with double sampling technique implemented with switch capacitor amplifier. 展开更多
关键词 CMOS image sensor active pixel fixed pattern noise double sampling offset compensation
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Area-Efficient Low Power CMOS Image Sensor Readout Circuit with Fixed Pattern Noise Cancellation 被引量:2
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作者 赵士彬 姚素英 +1 位作者 聂凯明 徐江涛 《Transactions of Tianjin University》 EI CAS 2010年第5期342-347,共6页
A low cost of die area and power consumption CMOS image sensor readout circuit with fixed pattern noise(FPN) cancellation is proposed.By using only one coupling capacitor and switch in the double FPN cancelling correl... A low cost of die area and power consumption CMOS image sensor readout circuit with fixed pattern noise(FPN) cancellation is proposed.By using only one coupling capacitor and switch in the double FPN cancelling correlative double sampling(CDS),pixel FPN is cancelled and column FPN is stored and eliminated by the sampleand-hold operation of digitally programmable gain amplifier(DPGA).The bandwidth balance technology based on operational amplifier(op-amp) sharing is also introduced to decrease the power dissi... 展开更多
关键词 imaging system image sensor low power electronic CAPACITOR operational amplifier fixed pattern noise bandwidth balance technology op-amp sharing
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Simulation of Quantum Noise in the Low-Light-Level Imaging System 被引量:3
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作者 邹正峰 芦汉生 +1 位作者 白廷柱 高稚允 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期186-190,共5页
A mathematical model of quantum noise having much effect on the low light imaging system is set up. To simulate the quantum noise, the random numbers obeying noise distribution must be formed and are weighted on the... A mathematical model of quantum noise having much effect on the low light imaging system is set up. To simulate the quantum noise, the random numbers obeying noise distribution must be formed and are weighted on the basis of the model created. Three uniform random sequences are built by the linear congruential method, of which two are used to form integer number and decimal fraction parts of the new random sequence respectively and the third to shuffle the new sequence. And then a Gauss sequence is formed out of uniform distribution by a function transforming method. It actualizes the simulation in real time of quantum noise in the low light imaging system, where video flow is extracted in real time, the noise summed up and played back side by side with the original video signs by a simulation software. 展开更多
关键词 SIMULATION quantum noises low light level imaging
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Combined Novel Gate Level Model and Critical Primary Input Sharing for Genetic Algorithm Based Maximum Power Supply Noise Estimation
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作者 田志新 刘勇攀 杨华中 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第9期1375-1380,共6页
A gate level maximum power supply noise (PSN) model is defined that captures both IR drop and di/dt noise effects. Experimental results show that this model improves PSN estimation by 5.3% on average and reduces com... A gate level maximum power supply noise (PSN) model is defined that captures both IR drop and di/dt noise effects. Experimental results show that this model improves PSN estimation by 5.3% on average and reduces computation time by 10.7% compared with previous methods. Furthermore,a primary input critical factor model that captures the extent of primary inputs' PSN contribution is formulated. Based on these models,a novel niche genetic algorithm is proposed to estimate PSN more effectively. Compared with general genetic algorithms, this novel method can achieve up to 19.0% improvement on PSN estimation with a much higher convergence speed. 展开更多
关键词 power supply noise gate level model niche genetic algorithm
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Subjective annoyance caused by indoor low-level and low frequency noise and control method 被引量:2
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作者 DIGuo-qing ZHANGBang-jun SHANGQi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第1期135-140,共6页
The influence of low_level noise has not been widely noticed. This paper discovered that low_level and low frequency noise(A_weighted equivalent level L eq <45 dB) causes higher probability of subjective annoyance.... The influence of low_level noise has not been widely noticed. This paper discovered that low_level and low frequency noise(A_weighted equivalent level L eq <45 dB) causes higher probability of subjective annoyance. The fuzzy mathematic principle was applied to deal with the threshold level of subjective annoyance from noise in this study; there is preferable relationship between the indoor noise and noise annoyance at low frequency noise level. Study indicated at the same centered noise level, the change of annoyance probability is mainly caused by the change of the frequency spectrum characteristic of the indoor noise. Under low noise level environment, without change of the medium_low frequency noise, the slight increase of medium_high frequency noise level with the help of noise sheltering effect can significantly reduce the noise annoyance. This discovery brings a new resolution on how to improve the environmental quality of working or living places. A noise control model is given in this study according to the acoustic analysis. 展开更多
关键词 low-level noise subjective annoyance threshold level structural noise indoor noise noise control
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Comparison of noise-levels between superconducting gravimeter and gPhone gravimeter 被引量:4
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作者 Kun Zhang Ziwei Liu +1 位作者 Xiaotong Zhang Ying Jiang 《Geodesy and Geodynamics》 2018年第6期498-503,共6页
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关键词 Superconducting gravimeter gPhone gravimeter noise level SNM SSNM
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The influence of observation environment on background noise level of gPhone gravimeter 被引量:6
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作者 Xiaotong Zhang Ying Jiang +1 位作者 Kun Zhang Xinlin Zhang 《Geodesy and Geodynamics》 2017年第6期443-447,共5页
Based on the observations of 36 gPhone gravimeters in 2015, the background noise levels in the seismic frequency band(200-600 s) and sub-seismic band(1-6 h) are calculated. The differences in the PSD(power spectr... Based on the observations of 36 gPhone gravimeters in 2015, the background noise levels in the seismic frequency band(200-600 s) and sub-seismic band(1-6 h) are calculated. The differences in the PSD(power spectrum density) of each band of gPhone gravimetric gauges in different surrounding environments were analyzed and compared with Peterson's NLNM(new low-noise model) which is derived from the envelope at the power spectrum density of 75 seismograph stations around the world. The results showed that: the influence of station type on the noise magnitude of gPhone gravimeter is very small; The seismic band noise magnitude(hereinafter referred to as SNM) and the sub-seismic band noise magnitude(hereinafter referred to as SSNM) in the coastal gPhone gravimeter are higher than those of inland stations. Although the local hydrological change has a great influence on the gravity observation, the rainfall is not directly relative to the noise magnitude of the instrument. Except 3 coastal stations, the eight stations which had the highest amplitudes in the SNM were located near the seismic belt. This indicates that the SNM of the gPhone Gravimeter may reflect some seismic information.Compared with the NLNM model, the PSD of the gPhone gravimeter is lower than the NLNM model in the long period band(〈3×10^(-5)Hz), indicating that the gPhone gravimeter is more suitable for detecting long-period signals(〉10 h) than the seismometer. 展开更多
关键词 gPhone gravimeter Background noise level NLNM Observation environment
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Experimental and Numerical Study of the Key Non-Dimensional Geometrical Parameters on the Noise Level of Dry-Type Cast Resin Transformers 被引量:2
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作者 Mahdi Soltanmohammadi Vahid Monfared 《Sound & Vibration》 2019年第5期177-198,共22页
Dry-Type Cast Resin Distribution Transformers(CRT)is the secondgeneration of air-cooled distribution transformers where oil is replaced by resin for electrical insulation.CRT transformers may installed indoor adjacent... Dry-Type Cast Resin Distribution Transformers(CRT)is the secondgeneration of air-cooled distribution transformers where oil is replaced by resin for electrical insulation.CRT transformers may installed indoor adjacent to or near residential areas since they are clean and safe comparing to the conventional transformers.But,as it is obvious,noise discrepancy is intrinsically accompanied with all types of transformers and is inevitable for CRT transformers too.Minimization of noise level caused by such these transformers has biological and ergonomic importance.As it is known the core of transformers is the main source of the noise generation.In this paper,experimental and numerical investigation is implemented for a large number of fabricated CRT transformers in IT Co(Iran Transfo Company)to evaluate the effective geometrical parameters of the core on the overall sound level of transformers.Noise Level of each sample is measured according to criteria of IEC60651 and is reported in units of Decibel(dB).Numerical simulation is done using noncommercial version of ANSYS Workbench software to extract first six natural frequencies and mode shapes of CRT cores which is reported in units of Hz.Three novel non-dimensional variables for geometry of the transformer core are introduced.Both experimental and numerical results show approximately similar response to these variables.Correlation between natural frequencies and noise level is evaluated statistically.Pearson factor shows that there is a robust conjunction between first two natural frequencies and noise level of CRTs.Results show that noise level decreases as the two first natural frequencies increases and vice versa,noise level increases as the two natural frequencies of the core decreases.Finally the noise level decomposed to two parts. 展开更多
关键词 EXPERIMENTAL FEM mean noise level CRT transformers IEC60651
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Noise level estimation method with application to EMD-based signal denoising 被引量:3
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作者 Xiaoyu Li Jing Jin +1 位作者 Yi Shen Yipeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期763-771,共9页
This paper proposes a new signal noise level estimation approach by local regions. The estimated noise variance is applied as the threshold for an improved empirical mode decomposition(EMD) based signal denoising me... This paper proposes a new signal noise level estimation approach by local regions. The estimated noise variance is applied as the threshold for an improved empirical mode decomposition(EMD) based signal denoising method. The proposed estimation method can effectively extract the candidate regions for the noise level estimation by measuring the correlation coefficient between noisy signal and a Gaussian filtered signal. For the improved EMD based method, the situation of decomposed intrinsic mode function(IMFs) which contains noise and signal simultaneously are taken into account. Experimental results from two simulated signals and an X-ray pulsar signal demonstrate that the proposed method can achieve better performance than the conventional EMD and wavelet transform(WT) based denoising methods. 展开更多
关键词 signal denoising empirical mode decomposition(EMD) Gaussian filter correlation coefficient noise level estimation
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Evaluation of Individual and Environmental Sound Pressure Level and Drawing Noise-Isosonic Maps Using Surfer V.14 and Noise at Work V.5.0 被引量:1
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作者 Sajad Zare Rasoul Hemmatjo +3 位作者 Hossein ElahiShirvan Ashkan Jafari Malekabad Mansour Ziaei Farshad Nadri 《Sound & Vibration》 EI 2021年第2期163-171,共9页
Noise pollution is one of the common physical harmful factors in many work environments.The current study aimed to assess personal and environmental sound pressure level and project the sound-Isosonic map in one of th... Noise pollution is one of the common physical harmful factors in many work environments.The current study aimed to assess personal and environmental sound pressure level and project the sound-Isosonic map in one of the Razavi Khorasan Paste manufacture using Surfer V.14 and Noise at work V.5.0.This cross-sectional,descrip-tive study is analytical that was conducted in 2018 in the Paste factory that contains Canister,production and Brewing unit.Following ISO 9612:2009,Casella Cel-320 was used to measure personal sound pressure level,while CEL-450 sound level meter(manufactured by Casella-Cel,the UK)was employed to assess environmental sound pressure level.Statistical analyzes was done using SPSS V.18 and Linear Regression test.The sound-isosonic maps were projected using Surfer V.14 and Noise at work V.5.0.The results of assessing personal sound pressure level indicated that the highest received dose(172.21%)and personal equivalent sound level(87.36 dBA)were recorded for workers in the Canister unit.According to results of measuring of the environmental sound pressure level,out of 16 measurement stations in this unit,overall 87.5%were regarded as danger and caution areas.The lowest and highest sound pressure levels in this units were 61 dBA and 92 dBA that belong to Brewing and Canister units respectively.Results indicate Over 75%of the Canister and production units had a sound pressure level greater than 85 dBA and these two units were regarded as the most dangerous area in terms of noise pollution.It is there-fore necessary to implement noise control measures,apply hearing protection program and auditory tests among workers in these units. 展开更多
关键词 Sound pressure level personal sound environmental sound sound map isosonic map SURFER noise at work
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A study on aerodynamic noise characteristics of a high-speed maglev train with a speed of 600 km/h
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作者 Jie Zhang Yuwei Wu +2 位作者 Jianyong Gao Guangjun Gao Zhigang Yang 《Railway Sciences》 2023年第3期310-326,共17页
Purpose–This study aims to explore the formation mechanism of aerodynamic noise of a high-speed maglev train and understand the characteristics of dipole and quadrupole sound sources of the maglev train at different ... Purpose–This study aims to explore the formation mechanism of aerodynamic noise of a high-speed maglev train and understand the characteristics of dipole and quadrupole sound sources of the maglev train at different speed levels.Design/methodology/approach–Based on large eddy simulation(LES)method and Kirchhoff–Ffowcs Williams and Hawkings(K-FWH)equations,the characteristics of dipole and quadrupole sound sources of maglev trains at different speed levels were simulated and analyzed by constructing reasonable penetrable integral surface.Findings–The spatial disturbance resulting from the separation of the boundary layer in the streamlined area of the tail car is the source of aerodynamic sound of the maglev train.The dipole sources of the train are mainly distributed around the radio terminals of the head and tail cars of the maglev train,the bottom of the arms of the streamlined parts of the head and tail cars and the nose tip area of the streamlined part of the tail car,and the quadrupole sources are mainly distributed in the wake area.When the train runs at three speed levels of 400,500 and 600 km$h1,respectively,the radiated energy of quadrupole source is 62.4%,63.3%and 71.7%,respectively,which exceeds that of dipole sources.Originality/value–This study can help understand the aerodynamic noise characteristics generated by the high-speed maglev train and provide a reference for the optimization design of its aerodynamic shape. 展开更多
关键词 High-speed maglev train Aerodynamic noise Penetrable integral surface Large eddy simulation Speed level
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Noise Exposure Levels in Basic School Environments in a City in Ghana 被引量:1
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作者 Lois N. K. Quartey Samuel Amos-Abanyie Samuel O. Afram 《Open Journal of Civil Engineering》 2021年第1期81-95,共15页
Basic schools that are located in heavily populated residential and commercial areas in Ghana are exposed to environmental noise that can have detrimental effects on the academic attainments of children. Limited studi... Basic schools that are located in heavily populated residential and commercial areas in Ghana are exposed to environmental noise that can have detrimental effects on the academic attainments of children. Limited studies have been conducted on noise level in basic schools to date in Ghana. The objective of the study was to assess noise levels in and around learning spaces in basic schools in Ghana with </span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">a </span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;">focus on Kumasi.</span><i> </i><span style="font-family:Verdana;">A survey employing the use of interviews and an empirical monitoring of noise levels in and around learning spaces in four selected basic schools were adopted. The study revealed that mean outdoor and indoor noise levels exceed the World Health Organisation permissible limits by 30 - 40 percent and 90 - 107 percent respectively for schools in the commercial zones and schools that are located near highways. The school that is sited in an educational environment with a setback from the highway attained mean noise levels ranging from 1.2 percent below to 3.7 percent above the permissible limits for outdoor and between 64 - 105 percent for indoor. The outcome of the study is expected to engender the design of environmental noise resilient buildings to facilitate teaching and learning in basic schools in Ghana</span></span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">. 展开更多
关键词 Environmental noise Sound level Basic Schools Central Business District Kumasi
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A Simple Approach to Determine Noise Frequency of Boiler Drum Level
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作者 余南华 苏明 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第1期66-70,共5页
This paper proposed a simple approach to determine noise frequency of boiler drum level in order to improve control performance. Based on analysis of uncertainty of drum level, the redundant oscillation component of s... This paper proposed a simple approach to determine noise frequency of boiler drum level in order to improve control performance. Based on analysis of uncertainty of drum level, the redundant oscillation component of signal, noise is ascribed to the surface wave of drum water. According to the characteristic of surface wave, a new method was proposed to determine noise’s frequency band. By gradually removing the lowest frequency component of signal, the variance of remained component is calculated and observed. An apparent turning point was found and the corresponding critical frequcncy was determined. With this result a low-pass filter was designed to separate noise component. Finally validation is conducted by comparing the proposed method and conventional ones. Results show the accuracy and simpleness of the proposed method. 展开更多
关键词 BOILER drum level noise cutoff frequency low-pass filter
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Employment and development levels in rural areas of the Russian Federation
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作者 Guzel SALIMOVA Gulnara NIGMATULLINA +2 位作者 Gamir HABIROV Alisa ABLEEVA Rasul GUSMANOV 《Regional Sustainability》 2024年第3期124-134,共11页
The development of agro-industrial complex is important for ensuring national food security and national health.The development of rural areas is subject to the development of agriculture and local infrastructure,as w... The development of agro-industrial complex is important for ensuring national food security and national health.The development of rural areas is subject to the development of agriculture and local infrastructure,as well as the availability of various services.This study selected 15 indicators in 2021 to analyze the employment and development levels in rural areas of 71 regions of the Russian Federation using the analytical grouping method.The results indicated that 20 regions(Group 1)had the highest percentage of rural population(33.10%).The percentage of population engaged in agriculture had the highest value(12.40%)in 31 regions(Group 2).Moreover,20 regions(Group 3)had the highest investments in fixed assets at the expense of municipal budget(11.80 USD/person).Increasing the investments in fixed assets carried out from the budget of the municipality can improve the employment level in rural areas.Then,we used cluster analysis to divide 14 regions of the Volga Federal District in the Russian Federation into 3 clusters.Cluster 1 covered Kirov Region and Republic of Mari El;Cluster 2 included Ulyanovsk Region,Saratov Region,Nizhny Novgorod Region,Perm Territory,Orenburg Region,Chuvash Region,and Republic of Mordovia;and Cluster 3 contained Republic of Tatarstan,Samara Region,Udmurtian Republic,Penza Region,and Republic of Bashkortostan.Results indicated that the 2 regions of Cluster 1 need to increase the availability of resources and natural gas and improve the investment attractiveness of rural areas.The 7 regions of Cluster 2 needed to develop infrastructure,public services,and agricultural production.We found the highest employment level in rural areas,the largest investments in fixed assets at the expense of municipal budget,the largest residential building area per 10,000 persons,and the largest individual residential building area in the 5 regions of Cluster 3.This study makes it possible to draw up a comprehensive regional development program and proves the need for the development of rural areas,which is especially important for the sustainable development of the Russian Federation. 展开更多
关键词 Rural areas Employment level Labor productivity Investments in fixed assets Sustainable Development Goal(SDG) Russian Federation
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Presenting a Signal to Noise Ratio Model Based on the Combined Effect ofSound Pressure Level/frequency, Exposure Time and Oral Potassium:Experimental Study in Rats
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作者 Parvin Nassiri Sajad Zare +3 位作者 Mohammad Reza Monazzam Akram Pourbakht Rasoul Hemmatjo Hossein ElahiShirvan 《Sound & Vibration》 EI 2020年第1期17-25,共9页
Exposure to noise can lead to anatomical,nonauditory,and auditory impacts.The auditory influence of noise exposure is manifested in the form of Noise-induced hearing loss(NIHL).The current study aimed at present a sig... Exposure to noise can lead to anatomical,nonauditory,and auditory impacts.The auditory influence of noise exposure is manifested in the form of Noise-induced hearing loss(NIHL).The current study aimed at present a signal to noise ratio model of otoacoustic emission of rats’ears in the light of the combined effect of sound pressure level,sound frequency,exposure time,and potassium concentration of the used water.In total,36 adult male rates,whose age varied from 3 to 4 months and had a weight of 200±50 g,were randomly divided into 12 groups,with each group consisting of 3 rats.The rats in both groups(case and control groups)were exposed to SPLs of 85,95,and 105 dB,emitted from sources that generated white noise.A distortion product otoacoustic emission(DPOAE)machine(4000 I/O manufactured by Homoth of Germany)was utilized to gauge the signal to noise ratio(SNR)of otoacoustic emissions of rats’ears at various frequencies in an acoustic room.The inclusion criterion was SNR≥6 dB.The collected data were fed into the Statistical Package for Social Sciences(SPSS)version 18,followed by conducting descriptive and inferential data analysis procedures.The results of SNR analysis indicated that over 82%of all data had SNRs that were equal to or greater than 6 dB.These data were considered as acceptable response.Furthermore,SPL and sound frequency had significant associations with SNR(P<0.0001).Exposure time also significantly correlated with SNR(P=0.008).However,the potassium concentration of the used water had no significant correlation with SNR(P=0.97).High sound pressure levels result in lower DPOAE.Furthermore,higher frequency leads to higher SNR.On the contrary,longer exposure time reduces SNR.Finally,the potassium concentration of the used water has no effect on SNR. 展开更多
关键词 noise sound pressure level POTASSIUM DPOAE RAT
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Evaluation of Environmental Sound Pressure Level,Drawing of Noise-Isosonic Map Using Surfer V.19,and Prioritization of Engineering Noise Control Methods Using the Analytic Hierarchy Process(AHP):A Field Study in CGS Stations
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作者 Sajad Zare Abdolrasoul Rahmani +3 位作者 Javad Korouzhdeh Masoud Hajghani Rouhollah Rostami Reza Esmaeili 《Sound & Vibration》 EI 2022年第3期275-291,共17页
Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and impl... Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and implement noise control plans in occupational environments is necessary.Thus,the present study aimed to review environmental sound measurements,drawing of noise maps,and prioritizing the engineering noise control methods using the Analytic Hierarchy Process(AHP).This study was a descriptive-analytical study that aimed to assess occupational noises and present a control plan in the City Gas Stations(CGSs)of Kerman,Iran in 2021.The present study was done in two phases.In the first phase,six CGSs were investigated to measure and evaluate the noise.In addition,the noise map of a CGS was drawn using the Surfer software.Finally,the AHP was used in the second phase of the research to prioritize the control measures.In this phase,four criteria and ten alternatives were identified.According to first phase results,the sound pressure level(SPL)of the stations varied from 76 to 98 dBA.Besides,the majority of the studied stations had a sound level higher than 85 dBA(danger zone).The second phase of the study showed that out of the four evaluated criteria,the executability criterion had the highest impact and the cost criterion had the lowest impact on the selection of control measures with a weight of 0.587 and 0.052,respectively.Based on the results of prioritization of the alternatives,using a silenced regulator(weight of 0.223)and increasing the thickness of the tube(weight of 0.023)had the highest and lowest priorities among the alternatives,respectively.The use of engineering noise control methods such as using silenced regulators was the best way to control the noises of CGSs.Additionally;it is noteworthy that AHP is a practical method for prioritizing alternatives to achieve the most accurate decision-making.The results of AHP can be of great help to health and safety experts and managers in choosing the sound engineering control measures more precisely. 展开更多
关键词 Engineering noise control sound pressure level noise map analytic hierarchy process
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Using Ambient Noise to Study the Seismic Velocity Changes Caused by the Rise and Fall of the Water Level in the Zipingpu Reservoir Region
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作者 An Yanru Zhang Xiaodong 《Earthquake Research in China》 CSCD 2017年第1期51-65,共15页
We study the feature of media changes beneath the Zipingpu reservoir and discuss the process of permeation with the water level rise and fall of the reservoir from January 2005 to January 2008 from ambient noise cross... We study the feature of media changes beneath the Zipingpu reservoir and discuss the process of permeation with the water level rise and fall of the reservoir from January 2005 to January 2008 from ambient noise cross correlation by using continuous seismic data recorded by the stations of Zipingpu seismic network and YZP station. A moving-window cross-spectrum technique has been used to calculate the relative seismic velocity changes between station pairs. Results revealed an obvious relationship between relative seismic velocity, and the water level changes with a time delay that may be caused by permeation during three main impoundments and two large scale disemboguements. Impoundment generates a fast and large impact on the superficial layer, and the changes of seismic velocity is the result of increased pressure and permeation during the impoundment. At the first impoundment, the main effect factor is pressure. During the next two process of impoundment, permeation becomes the main effect factor, affecting the fault at a depth of about 8kin. 展开更多
关键词 Ambient noise Zipingpu Reservoir Water level Relative seismic velocity changes
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Evaluation of Noise Levels in Different Industrial Sectors within the Gaza Strip: A Pilot Study
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作者 Abed Schokry 《材料科学与工程(中英文A版)》 2015年第5期202-208,共7页
关键词 工业部门 噪音 地带 加沙 噪声暴露 试验 评价
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Orbital pacing and secular evolution of lake-level changes reconstructed by sedimentary noise modeling during the Early Jurassic icehouses-(super)greenhouses
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作者 Meng LI Xin LI +5 位作者 Stephen P.HESSELBO Mingjie LI Wenjin LIU Wei WU Jienan PAN Ruizhen GAO 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第1期252-267,共16页
Lake-level changes can significantly affect paleoenvironmental evolution,resource occurrence,terrestrial carbon budget,and biodiversity in continental basins.Climate is one of the most critical factors controlling lak... Lake-level changes can significantly affect paleoenvironmental evolution,resource occurrence,terrestrial carbon budget,and biodiversity in continental basins.Climate is one of the most critical factors controlling lake-level changes.Paleoclimate of the Early Jurassic has been evidenced by oscillating icehouses to(super)greenhouses with interrupted intermittent extreme climatic events(hyperthermal and cooling),e.g.,the Toarcian oceanic anoxic event(~183 Ma)and the late Pliensbachian cooling event(~185 Ma).Lake-level evolution and hydrologic cycling on Earth’s surface during the Early Jurassic icehouses-to-(super)greenhouses are thus far poorly understood due to a lack of continuous high-resolution nonmarine evidence.Here we present a super-long nonmarine lake level record for this pivotal interval from the early Pliensbachian to Toarcian by sedimentary noise modeling,and construct a 16.7-Myr-long astronomical time scale(174.2 Ma to 190.9 Ma)based on cyclostratigraphy analysis of rock color datasets(CIE b*)of the Qaidam Basin.Our results document lake-level oscillations on a 5-to 10-million-year(Myr)scale which shows a pronounced correlation with long-term climate variation and extreme climatic events,and 1-to 2.5-Myr-scale lake-level changes that are prominently paced by the 2.4-Myr long-eccentricity forcing and the 1.2-Myr obliquity forcing.At the Pliensbachian Stage,the 1.2-Myr-scale lake-level changes are in phase with the coeval sealevel variations.Orbitally forced growth and decay of the ephemeral or permanent ice sheets in polar regions are interpreted to control the synchronous ups-and-downs of continental lake level and global sea level.However,during the Toarcian ice-free greenhouses to(super)greenhouses,the 1.2-Myr-scale lake-level variations show an anti-phase relationship with global sea level,indicating a‘seesaw’interaction between continental reservoirs(lakes and groundwater)and global oceans.The 2.4-Myr longeccentricity cycles mainly regulate variations of lake level and sea level by controlling the growth and decay of small-scale continental ice sheets,which is especially notable during the Pliensbachian Stage.These findings indicate a remarkable transition of hydrological cycling pattern during the Pliensbachian-Toarcian icehouses to(super)greenhouses,which provides new perspectives and evidence for investigating the hypothesis of global sea-level changes(e.g.,glacio-eustasy and aquifer-eustasy)and long-period astronomical forcing in nonmarine stratigraphy. 展开更多
关键词 Milankovitch cycles Orbital forcing Sedimentary noise model Lake level Continental basins
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