Evaluation of Digits-in-Noise Test and Hearing Handicap Inventory for Adults Screening in Patients with Occupational Noise-Induced Hearing Loss

Objective:To explore the clinical evaluation role of the Digits-in-Noise(DIN)test and Hearing Handicap Inventory for Adults Screening(HHIA-S)for patients with occupational noise-induced hearing loss and to observe and analyze their application values.Methods:Fifty patients with suspected occupational noise-induced hearing loss were randomly selected from the Department of Otolaryngology at the hospital as the research target.The collection period for the research cases spanned from January 2022 to November 2023,and all patients had a history of noise exposure.The DIN test and HHIA-S were used for hearing examinations,with clinical,comprehensive diagnosis serving as the gold standard to study their diagnostic performance.Results:The compliance rate of the DIN test was 88.00%,the HHIA-S’s compliance rate was 80.00%,and the combined compliance rate was 94.00%.The compliance rate of the DIN test and the combined compliance rates of the patients were statistically significant compared to the clinical gold standard data(P<0.05),while there was no difference between the compliance rate of the HHIA-S and the gold standard(P>0.05).The data shows that the sensitivity of the combined diagnosis is significantly higher than the sensitivity data of the DIN test and HHIA-S examination alone(P<0.05).Its specificity is 100.00%,and the accuracy data of the joint diagnosis in the degree were higher than those of the DIN test alone(P>0.05)and the HHIA-S alone(P<0.05).Conclusion:For patients with occupational noise-induced hearing loss,the joint evaluation of the DIN test and HHIA-S can significantly improve their diagnostic value with high sensitivity and accuracy.

The Effect of a High-Frequency-Hearing-Threshold Weighted Value on the Diagnosis of Occupational-Noise-Induced Deafness

Objective: In order to provide a theoretical basis for the revision of the current diagnostic criteria for occupational noise-induced deafness (ONID), we evaluated the degree of ONID by analyzing different high-frequency-hearing- threshold-weighted values (HFTWVs). Methods: A retrospective study was conducted to evaluate the diagnosis of patients with ONID from January 2016 to January 2017 in Guangdong province, China. Based on 3 hearing tests (each interval between the tests was greater than 3 days), the minimum threshold value of each frequency was obtained using the 2007 edition’s diagnostic criteria for ONID. The speech frequency and the HFTWVs were analyzed based on age, noise exposure, and diagnostic classi-fication using SPSS21.0. Results: 168 patients in total were involved in this study, 154 males and 14 females, and the average age was 41.18 ± 6.07. The diagnosis rate was increased by the weighted value of the high frequencies and was more than the mean value of the pure speech frequency (MVPSF). The diagnosis rate for the weighted 4 kHz frequency level increased by 13.69% (χ2 = 9.880, P = 0.002), the weighted 6 kHz level increased by 15.47% (χ2 = 9.985, P = 0.002), and the weighted 4 kHz + 6 kHz level increased by 15.47% (χ2 = 9.985, P = 0.002). The differences were all statistically significant. The diagnostic rate of the different thresholds showed no obvious difference between the genders. The age groups were divided into less than or equal to 40 years old (group A) and 40 - 50 years old (group B). There were several groups with a high frequency: high frequency weighted 4 kHz ( group A χ2 = 3.380, P = 0.050;group B χ2 = 4.054, P = 0.032), high frequency weighted 6 kHz (group A χ2 = 6.362, P = 0.012;group B χ2 = 4.054, P = 0.032), weighted 4 kHz + 6 kHz (group A χ2 = 6.362 P = 0.012;B χ2 = 4.054, P = 0.032) than those of MVPSF in the same group on ONID diagnosis rate. The differences between the groups were statistically significant. There was no significant difference between the age groups (χ2 = 2.265, P = 0.944). The better ear’s (the smaller hearing threshold weighted value) MVPSF and the weighted values for the different high frequencies were examined in light of the number of working years;the group that was exposed to noise for more than 10 years had significantly higher values than those of the average thresholds of each frequency band in the groups with 3 - 5 years of exposure (F = 2.271, P = 0.001) and 6 - 10 years of exposure (F = 1.563, P = 0.046). The differences were statistically significant. The different HFTWVs were higher than those of the MVPSF values, and the high frequency weighted 4 kHz + 6 kHz level showed the greatest difference, with an average increase of 2.83 dB. The diagnostic rate that included the weighted high frequency values was higher for the mild, moderate, and severe cases than those patients who were only screened with the pure frequency tests. The results of the comparisons of the diagnosis rates for mild ONID were as follows: the weighted 3 kHz high frequency level (χ2 = 3.117, P = 0.077) had no significant difference, but the weighted 4 kHz level (χ2 = 10.835, P = 0.001), 6 kHz level (χ2 = 9.985, P = 0.002), 3 kHz + 4 kHz level (χ2 = 6.315, P = 0.012), 3 kHz + 6 kHz level (χ2 = 6.315, P = 0.012), 4 kHz + 6 kHz level (χ2 = 9.985, P = 0.002), and 3 kHz + 4 kHz + 6 kHz level (χ2 = 7.667, P = 0.002) were significantly higher than the diagnosis rate of the mean value of the PSF. There was no significant difference between the 2 groups for the moderate and severe grades (P > 0.05). Conclusion: Different HFTWVs increase the diagnostic rate of ONID. The weighted 4 kHz, 6 kHz, and 4 kHz + 6 kHz high frequency values greatly affected the diagnostic results, and the weighted 4 kHz + 6 kHz high frequency hearing threshold value has the maximum the effect on the ONID diagnosis results.

Analysis of occupational noise for the healthy life according to the job characteristics

Noise is known that the physical risk factors defined as any unwanted sound. It can induce the health problems such as hearing loss or annoyance. The objective of this study was to assess the occupational noise exposure of nine groups for twenty peoples according to job characteristics and to compare the noise level by different variables. Personal noise levels were measured for three times using by dosimeters for each participant in Korea. The mean time weighted average noise level (TWA) of total was 73.2 ± 11.5 dBA by American conference of governmental industrial hygienists (ACGIH) standard. Especially, Korean classical music students were highly exposed to 93.2 ± 6.2 dBA but, office workers were 63.2 ± 6.6 dBA. In case of peak sound pressure level (Lpeak), Korean classical music students and firefighters were exposed to the highest level of 151.8 dBC and 145.8 dBC during playing and dispatching, respectively. The analysis of noise level showed that Leq had positive correlations between TWA by ministry of employment and labour (MOEL) (r = 0.98, p < 0.01) and TWA by ACGIH (r = 0.98, p < 0.01). Unlikely other groups, the noise exposure level of the Korean classical music students were exceeded the ACGIH standard. These results suggest that Korean classical music students were exposed high noise level and some solutions are need to reduce the noise exposure level such as using hearing protect device.

A cross-sectional study on the effects of occupational noise exposure on hypertension or cardiovascular among workers from automobile manufacturing company of Chongqing, China

For the past few years, noise pollution has been more and more serious, and it may lead to several diseases. While the humans expose to noise in quantity for a long time, their blood pressure will change, and even cause changes in cardiac function. In our study, we attempt to find the relationship between occupational noise and hypertension and impaired hearing, cardiac function. It may be helpful to obtain some useful information on occupational noise exposure of humans. The participants were divided into noisy group ≥90 dB (A) and non-noisy group ≤70 dB (A). We performed this research in an automobile manufacturing company of Chongqing, China during 2011-2012. Our study showed that there may be positive associations between?occupational noise and hypertension and impaired hearing, but no conclusion can be drawn between occupational noise and ECG.

Assessment of occupational noise pollution for metal industries in Kingdom of Saudi Arabia

The main objectives of this study was measuring levels of noise generated by machinery that workers at metal industrial facilities in the Kingdom of Saudi Arabia （KSA） are exposed to as well as to determine if these levels were in conformity with adopted standards. To achieve the objectives of this study the following six metal industrial facilities were selected： a foundry plant, a building-metal production factory, a cold processing steel manufacturing plant, a hollow-metal door and doorframe manufacturer, a car-exhaust-system factory and a metal-can producer. The study found that workers operating machinery without any kind of protection were exposed to unacceptably high levels of noise that exceeded the internationally acceptable values as per occupational noise exposure-1910.95 regulations adopted standard. It was founded that 73% of work site investigated have noise level over 85 dB. A level of 116 dB was recorded at steel plant fiat section product with continuous occupation and 115.2 dB in metal product factory with labor continuous occupation. Based on the results obtained in this study, it is evident that a competent environmental and health agency needs to be established and that stricter noise-level standards ought to be enforced in order to protect employee health.

Effects of Occupational Noise on the Hearing Ability of Outpatient Clinic Nurses in Different Classes of Hospitals in Guangzhou

Background: Occupational noise can induce hearing impairment. Work-related hearing impairment has become a growing threat to medical practitioners who feel anxious about occupational noise exposure and its health outcomes or even experience auditory dysesthesia (including drumming, distending pain in the ears, and otalgia) after long-term exposure to a noisy work environment. Objective: To investigate the effects of occupational noise on the hearing ability of outpatient clinic nurses in Grade III, Level A and Grade II, Level A hospitals in Guangzhou. Methods: During June 2019, noise monitoring was performed by quantifying the noise levels at four measuring points (reception, waiting area, hallway, blood-sampling room) in five Grade III, Level A and five Grade II, Level A hospitals, in Guangzhou, four times a day (8 AM, 10 AM, 2 PM, and 4 PM) for 19 working days, using a professional noise measuring application for smartphones. The measurements were verified and used to create a database in Excel. Data analysis was conducted using SPSS22.0, and questionnaires were distributed to nurses who had been working at outpatient clinics for five years and above to assess the impacts of occupational noise exposure on the hearing ability. Results: In the Grade III, Level A hospitals, the sound levels at the four measuring points during the specific time periods were 4.92 - 6.75 dB above the permissible limit of 55 dB and were all significantly higher than the sound levels at the outpatient clinics of the Grade II, Level A hospitals (P Conclusions: Exposure to excess noise can lead to auditory dysesthesia in outpatient clinic nurses. Compared to those from Grade II, Level A hospitals, outpatient clinic nurses from Grade III, Level A hospitals are at higher risk of auditory dysesthesia. The noise levels at outpatient clinics should be closely monitored, and effective measures should be taken to reduce occupational noise exposure. Outpatient clinic nurses should enhance protective measures and receive preventive health exams on a regular basis.

Reducing Occupational Noise Propagated from Centrifugal Fan through Dissipative Silencers:A Field Study

Acoustic performance of dissipative silencer was evaluated to determine the effectiveness of perforated duct porosity and absorbent material density in reducing occupational noise exposure propagated from centrifugal fan.Design charts were applied to predict noise reduction and length of a dissipative silencer.Dissipative silencers with various punched duct porosity(14%,30%and 40%)and sound absorbent density(80 Kg/m^(3),120 Kg/m^(3),and 140 Kg/m^(3))were designed and fabricated.According to ISO9612 and ISO11820,noise level was measured before and after installing all nine test silencers at fixed workstations around the discharge side of a centrifugal fan in a manufacturing plant.On average,the noise level at the discharge side of a fan without silencer was measured to be 93.6 dBA,whereas it was significantly mitigated by 67.4 dBA to 70.1 dBA after installing all silencers.Dynamic insertion loss for a dissipative silencer with 100 cm length was predicted to be 27.9 dB,which was in agreement with experimental ones.Although,there was no significant differences between insertion loss of silencers,the one with 30%porosity and 120 Kg/m^(3)rock wool density had the highest insertion loss of 26.2 dBA.Dissipative silencers noticeably reduced centrifugal fan noise exposures.Increasing sound absorbent density and duct porosity up to a certain limit could probably be effective in noise reduction of dissipative silencers.

Influence of Occupational Noise Exposure on Cognitive Ability of Grinders

Purpose: To investigate whether long-term noise exposure affects the cognitive ability of grinders. Methods: Cumulative noise exposure (CNE) and LAeq.8h determination were used to characterize the level of individual noise exposure;the Montreal Cognitive Assessment (MoCA) test (Beijing version) was used to evaluate cognitive function. Results: We compared the basic situation of workers in different groups and individual noise exposure intensity of grinders was monitored. Multiple linear-regression analysis was made and score of MoCA in different group was finally drawn. Conclusion: CNE and total score of MoCA have the relationship of negative correlation (r = -0.303, p < 0.05) which means long-term occupational noise exposure can affect the cognitive ability of grinders.

Positive Associations between Bilateral High-Frequency Hearing Loss and Hypertension Risk in Short-Term Occupational Noise Exposure

Noise is one of the most common occupational hazards worldwide[1], and millions of workers are exposed to harmful levels of noise in the workplace[2]. Noise-induced hearing loss(NIHL) is a leading cause of occupational and recreational injury and disease[3]. There is evidence that occupational noise exposure is also associated with other health effects, such as hypertension and cardiovascular diseases, digestive disorders, behavioral disorders.

The comparison of auditory behavioral and evoked potential responses (steadystate and cortical) in subjects with occupational noise-induced hearing loss

Objective: To define difference scores between PTA, ASSR and CERA thresholds in subjects with occupational NIHL.Design: 44 subjects undergoing a medico-legal expert assessment for occupational NIHL and fulfillingcriteria of reliability were considered. Assessment included: PTA, 40 Hz binaural multiple ASSR and CERA(1-2-3 kHz).Results: The respective average difference scores (ASSR - PTA) for 1, 2 and 3 kHz are 13.01 (SD 10.19) dB,12.72 (SD 8.81) dB and 10.38 (SD 8.19) dB. The average (CERA - ASSR) difference scores are 1.25 (SD 14.63)dB for 1 kHz (NS), 2.73 (SD 13.03) dB for 2 kHz (NS) and 4.51 (SD 12.18) dB for 3 kHz. The correlationbetween PTA and ASSR (0.82) is significantly stronger than that between PTA and CERA (0.71). In a givensubject, PTA thresholds are nearly always lower (i.e., better) than ASSR thresholds, whatever the frequency (1-2-3 kHz) and the side (right e left). A significant negative correlation is found between thedifference score (ASSR e PTA) and the degree of hearing loss.Conclusion: ASSR outperforms CERA in a medicolegal context, although overestimating the behavioralthresholds by 10e13 dB.

Noise reduction mechanism of high-speed railway box-girder bridges installed with MTMDs on top plate

The issue of low-frequency structural noise radiated from high-speed railway(HSR) box-girder bridges(BGBs) is a significant challenge worldwide. Although it is known that vibrations in BGBs caused by moving trains can be reduced by installing multiple tuned mass dampers(MTMDs) on the top plate, there is limited research on the noise reduction achieved by this method. This study aims to investigate the noise reduction mechanism of BGBs installed with MTMDs on the top plate. A sound radiation prediction model for the BGB installed with MTMDs is developed, based on the vehicle–track–bridge coupled dynamics and acoustics boundary element method. After being verified by field tested results, the prediction model is employed to study the reduction of vibration and noise of BGBs caused by the MTMDs. It is found that installing MTMDs on top plate can significantly affect the vibration distribution and sound radiation law of BGBs. However, its impact on the sound radiation caused by vibrations dominated by the global modes of BGBs is minimal. The noise reduction achieved by MTMDs is mainly through changing the acoustic radiation contributions of each plate of the bridge. In the lower frequency range, the noise reduction of BGB caused by MTMDs can be more effective if the installation of MTMDs can modify the vibration frequency and distribution of the BGB to avoid the influence of small vibrations and disperse the sound radiation from each plate.

Adaptive Bistable Stochastic Resonance Based Weak Signal Reception in Additive Laplacian Noise

Weak signal reception is a very important and challenging problem for communication systems especially in the presence of non-Gaussian noise,and in which case the performance of optimal linear correlated receiver degrades dramatically.Aiming at this,a novel uncorrelated reception scheme based on adaptive bistable stochastic resonance(ABSR)for a weak signal in additive Laplacian noise is investigated.By analyzing the key issue that the quantitative cooperative resonance matching relationship between the characteristics of the noisy signal and the nonlinear bistable system,an analytical expression of the bistable system parameters is derived.On this basis,by means of bistable system parameters self-adaptive adjustment,the counterintuitive stochastic resonance(SR)phenomenon can be easily generated at which the random noise is changed into a benefit to assist signal transmission.Finally,it is demonstrated that approximately 8dB bit error ratio(BER)performance improvement for the ABSR-based uncorrelated receiver when compared with the traditional uncorrelated receiver at low signal to noise ratio(SNR)conditions varying from-30dB to-5dB.

Wind Turbine Noise Reduction through Blade Retrofitting

This paper outlines a plan for the effective reduction of the audible sound level produced by aerodynamic noise from the power-generating turbine blades. The contribution of aerodynamic noise can be divided into two categories: inflow turbulence and airfoil self-noise. The base model and retrofit blade designs were modeled in SolidWorks. Subsequently, noise prediction simulations were conducted and compared to the base blade model to determine which modification provided the greatest benefit using SolidWorks Flow Simulation. The result of this project is a series of blade retrofit recommendations that produce a more acoustically efficient design and reduce noise complaints while enabling turbines to be placed in locations that require quieter operations.

Numerical Study on Reduction in Aerodynamic Drag and Noise of High-Speed Pantograph

Reducing the aerodynamic drag and noise levels of high-speed pantographs is important for promoting environmentally friendly,energy efficient and rapid advances in train technology.Using computational fluid dynamics theory and the K-FWH acoustic equation,a numerical simulation is conducted to investigate the aerodynamic characteristics of high-speed pantographs.A component optimization method is proposed as a possible solution to the problemof aerodynamic drag and noise in high-speed pantographs.The results of the study indicate that the panhead,base and insulator are the main contributors to aerodynamic drag and noise in high-speed pantographs.Therefore,a gradual optimization process is implemented to improve the most significant components that cause aerodynamic drag and noise.By optimizing the cross-sectional shape of the strips and insulators,the drag and noise caused by airflow separation and vortex shedding can be reduced.The aerodynamic drag of insulator with circular cross section and strips with rectangular cross section is the largest.Ellipsifying insulators and optimizing the chamfer angle and height of the windward surface of the strips can improve the aerodynamic performance of the pantograph.In addition,the streamlined fairing attached to the base can eliminate the complex flow and shield the radiated noise.In contrast to the original pantograph design,the improved pantograph shows a 21.1%reduction in aerodynamic drag and a 1.65 dBA reduction in aerodynamic noise.

Physical Layer Encryption of OFDM-PON Based on Quantum Noise Stream Cipher with Polar Code

Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security.

Vibration and noise mechanism of a 110 kV transformer under DC bias based on finite element method

Global energy and environmental issues are becoming increasingly problematic,and the vibration and noise problem of 110 kV transformers,which are the most widely distributed,have attracted widespread attention from both inside and outside the industry.DC bias is one of the main contributing factors to vibration noise during the normal operation of transformers.To clarify the vibration and noise mechanism of a 110 kV transformer under a DC bias,a multi-field coupling model of a 110 kV transformer was established using the finite element method.The electromagnetic,vibration,and noise characteristics during the DC bias process were compared and quantified through field circuit coupling in parallel with the power frequency of AC,harmonic,and DC power sources.It was found that a DC bias can cause significant distortions in the magnetic flux density,force,and displacement distributions of the core and winding.The contributions of the DC bias effect to the core and winding are different at Kdc=0.85.At this point,the core approached saturation,and the increase in the core force and displacement slowed.However,the saturation of the core increased the leakage flux,and the stress and displacement of the winding increased faster.The sound field distribution characteristics of the 110 kV transformer under a DC bias are related to the force characteristics.When the DC bias coefficient was 1.25,the noise sound pressure level reached 73.6 dB.

Can urban forests provide acoustic refuges for birds?Investigating the influence of vegetation structure and anthropogenic noise on bird sound diversity

As a crucial component of terrestrial ecosystems,urban forests play a pivotal role in protecting urban biodiversity by providing suitable habitats for acoustic spaces.Previous studies note that vegetation structure is a key factor influencing bird sounds in urban forests;hence,adjusting the frequency composition may be a strategy for birds to avoid anthropogenic noise to mask their songs.However,it is unknown whether the response mechanisms of bird vocalizations to vegetation structure remain consistent despite being impacted by anthropogenic noise.It was hypothesized that anthropogenic noise in urban forests occupies the low-frequency space of bird songs,leading to a possible reshaping of the acoustic niches of forests,and the vegetation structure of urban forests is the critical factor that shapes the acoustic space for bird vocalization.Passive acoustic monitoring in various urban forests was used to monitor natural and anthropogenic noises,and sounds were classified into three acoustic scenes(bird sounds,human sounds,and bird-human sounds)to determine interconnections between bird sounds,anthropogenic noise,and vegetation structure.Anthropogenic noise altered the acoustic niche of urban forests by intruding into the low-frequency space used by birds,and vegetation structures related to volume(trunk volume and branch volume)and density(number of branches and leaf area index)significantly impact the diversity of bird sounds.Our findings indicate that the response to low and high frequency signals to vegetation structure is distinct.By clarifying this relationship,our results contribute to understanding of how vegetation structure influences bird sounds in urban forests impacted by anthropogenic noise.

Dynamic properties of rumor propagation model induced by L´evy noise on social networks

Social networks are inevitably subject to disruptions from the physical world,such as sudden internet outages that sever local connections and impede information flow.While Gaussian white noise,commonly used to simulate stochastic disruptions,only fluctuates within a narrow range around its mean and fails to capture large-scale variations,L´evy noise can effectively compensate for this limitation.Therefore,a susceptible–infected–removed rumor propagation model with L´evy noise is constructed on homogeneous and heterogeneous networks,respectively.Then,the existence of a global positive solution and the asymptotic path-wise of the solution are derived on heterogeneous networks,and the sufficient conditions of rumor extinction and persistence are investigated.Subsequently,theoretical results are verified through numerical calculations and the sensitivity analysis related to the threshold is conducted on the model parameters.Through simulation experiments on Watts–Strogatz(WS)and Barab´asi–Albert networks,it is found that the addition of noise can inhibit the spread of rumors,resulting in a stochastic resonance phenomenon,and the optimal noise intensity is obtained on the WS network.The validity of the model is verified on three real datasets by particle swarm optimization algorithm.

A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network

This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN).

Dynamics and synchronization in a memristor-coupled discrete heterogeneous neuron network considering noise

Research on discrete memristor-based neural networks has received much attention.However,current research mainly focuses on memristor–based discrete homogeneous neuron networks,while memristor-coupled discrete heterogeneous neuron networks are rarely reported.In this study,a new four-stable discrete locally active memristor is proposed and its nonvolatile and locally active properties are verified by its power-off plot and DC V–I diagram.Based on two-dimensional(2D)discrete Izhikevich neuron and 2D discrete Chialvo neuron,a heterogeneous discrete neuron network is constructed by using the proposed discrete memristor as a coupling synapse connecting the two heterogeneous neurons.Considering the coupling strength as the control parameter,chaotic firing,periodic firing,and hyperchaotic firing patterns are revealed.In particular,multiple coexisting firing patterns are observed,which are induced by different initial values of the memristor.Phase synchronization between the two heterogeneous neurons is discussed and it is found that they can achieve perfect synchronous at large coupling strength.Furthermore,the effect of Gaussian white noise on synchronization behaviors is also explored.We demonstrate that the presence of noise not only leads to the transition of firing patterns,but also achieves the phase synchronization between two heterogeneous neurons under low coupling strength.