Статті в журналах: "Noise barriers Evaluation"

1

Wayson, Roger, John MacDonald, Ahmed EI-Assar, Win Lindeman, and Mariano Berrios. "Florida Noise Barrier Evaluation and Computer Model Validation." Transportation Research Record: Journal of the Transportation Research Board 1859, no. 1 (January 2003): 72–78. http://dx.doi.org/10.3141/1859-09.

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The results of a project that investigated the effectiveness of in situ noise barriers in Florida are presented. The prediction accuracy of the FHWA Traffic Noise Model (TNM) is compared with STAMINA 2.0 and 2.1 (Florida-specific). A total of 20 barrier sites were visited during a 3-year period that resulted in 844 discrete 20-min equivalent sound level (Leq) measurements behind the barriers. Barrier insertion loss was determined using the ANSI indirect barrier method. A methodology was developed to estimate shadow zone length created behind highway noise barriers. All of the barriers tested were effective (>5 dB:LAeq insertion loss at distances equivalent to the first row of homes, where LAeq is the A-weighted Leq) except one site because of marginal additional shielding from a berm–barrier combination. Only three sites had an insertion loss of less than 5 dB at distances representative of the second row of homes. Overall, measurements indicate that the barriers provide substantial sound level reduction for residents along the highway. TNM was the best prediction model when considering all test sites; however, the STAMINA models were more accurate at predicting source level. TNM predictions using the Average pavement input overpredicted the reference sound levels measured at these sites. TNM predictions using the OGAC (open-graded asphalt concrete) input were improved (under 2 dB:LAeq of error) over those using the Average pavement type input. This result is expected because Florida uses an open-graded asphalt friction mix.

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Marková, Petra, Vítězslav Křivánek, Blanka Hablovičová, and Jindřich Frič. "EVALUATION OF NOISE ATTENUATION OF BARRIERS WITH GREENERY IN THE CZECH REPUBLIC." Akustika, VOLUME 40 (2021): 8–17. http://dx.doi.org/10.36336/akustika2021408.

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The article is focused on the measurements of different types of “environmental” built noise barriers (semi-vegetation, green belt, barriers with vegetation) which were measured in the different places in the Czech Republic. In situ measuring was carried out in accordance with the standard ISO 1996. Short-term synchronous measurements were carried out in front of and behind the noise barrier and the effectiveness of noise barriers was determined. The measurement results show a slight increase in acute attenuation in anti-noise elements using vegetation. During the growing season, when greening occurs, a more pronounced acoustic attenuation compared to dormancy has been clearly demonstrated. This research was supported by the Ministry of Transport of the Czech Republic.

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Dasarathy, A. K., and M. Tamil selvi. "Noise Reduction Using Concrete Barriers: A Case Study." IOP Conference Series: Materials Science and Engineering 1197, no. 1 (November 1, 2021): 012010. http://dx.doi.org/10.1088/1757-899x/1197/1/012010.

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Abstract Noise pollution is becoming more and more acute, and hence many researchers are studying the noise attenuation effect and prevention of noise. In this study an attempt has been made to find the reduction in noise levels at National Highway 45 near peerkankaranai in Chennai. Two sensitive places were selected along NH 45 by examining attenuation of noise by providing noise barriers in the form of concrete structures. The primary goal of this project was to identify innovative design of noise barrier that has the potential to be implemented in NH 45, Chennai. Based on the research and evaluation conducted for this study, it was recommended that two innovative barrier designs be implemented in Chennai. First, a noise prediction is made at the specified location on the highway under certain traffic conditions in order to determine the noise level by measurement and decide on the barrier requirement. The installation of sound barriers is feasible enough to cause a significant decrease in noise pollution at the roads. Considerable noise attenuation is achieved by providing concrete noise barrier. The paper provides Leq at the time of traffic data recorded was 105.1 dBA at NH45 and 91.108 dBA at NH5 during the time of observation at installation of barrier the values are 70.09 dBA 79.11 dBA, respectively. Noise reduction is possible and noise reduction is predominantly reduced by providing barrier.

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Lacasta, A. M., A. Penaranda, I. R. Cantalapiedra, C. Auguet, S. Bures, and M. Urrestarazu. "Acoustic evaluation of modular greenery noise barriers." Urban Forestry & Urban Greening 20 (December 2016): 172–79. http://dx.doi.org/10.1016/j.ufug.2016.08.010.

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5

Ross, Jason C., Mark Arnoldy, and Jonathan Evans. "New Hampshire Department of Transportation Statewide Noise Barrier Study." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 24 (September 18, 2018): 144–53. http://dx.doi.org/10.1177/0361198118797188.

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This paper presents the results of a statewide noise barrier study for the New Hampshire Department of Transportation (NHDOT). The feasibility and reasonableness of noise barriers throughout the state has been evaluated according to NHDOT acoustical and cost-effectiveness criteria. The study has provided the DOT with an estimate of the potential noise barrier material costs associated with a newly implemented Type II noise barrier program. The study also has identified municipalities that the DOT can coordinate with for enacting noise-compatible planning regulations. The paper describes the methodology used to develop the screening-level noise barrier evaluation. Highway noise levels throughout the state and the distances from the highway where noise levels exceed the noise abatement criteria were determined. A method to predict the noise reduction of barriers (insertion loss) based on a simple geometrical relationship of receptors and potential noise barriers was established and has been shown to correlate well to detailed traffic noise models using actual roadway and terrain geometry. The simplified prediction method was used to evaluate over 300 miles of highway, 300 candidate noise barrier study areas, and over 30,000 receptors. This screening-level modeling approach is critical to the practicality of using the Traffic Noise Model across the entire state given the significant number of receptors and noise barrier study areas. The results of the study including information about all 30,000 receptors and 300 noise barrier study areas were collected in Google Earth™ data files for easy access when the DOT responds to noise complaints from the public.

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İLGÜREL, Nuri, Neşe YÜĞRÜK AKDAĞ, and Ali AKDAĞ. "EVALUATION OF NOISE EXPOSURE BEFORE AND AFTER NOISE BARRIERS, A SIMULATION STUDY IN ISTANBUL." JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 24, no. 4 (December 16, 2016): 293–302. http://dx.doi.org/10.3846/16486897.2016.1184671.

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İstanbul is the most prominent Turkish city in terms of the gradually worsening noise problems associated with the rapid increase in population. This study aims to investigate the noise exposure in the settlements around the link roads connecting the Bosporus Bridge to the European side of the city by the aid of simulations and noise mapping, in the frame of action planning studies performed in İstanbul. Noise maps were generated for Lden and Ln noise indicators with the help of a noise mapping software. Since a considerable part of the settlements is exposed to high noise levels, a noise barrier alongside the link road was proposed as a control measure by the aid of the acoustic simulation. Simulations with the noise barriers suggest that for the Lden time interval the noise affected area over 55 dba would reduce by 10%, the number of dwellings by 26% and the number of inhabitants by 25%, whereas for the Ln time interval the noise affected area over 45 dba would reduce by 5%, the number of dwellings by 20% and the number of inhabitants by 20%.

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Koh, Hyo-In, Seungho Jang, and Ji-Young Hong. "Investigation of Noise Spectrum Characteristics for an Evaluation of Railway Noise Barriers." International Journal of Railway 6, no. 3 (September 30, 2013): 125–30. http://dx.doi.org/10.7782/ijr.2013.6.3.125.

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8

Wu, Yizhou, Wentao Li, Jiacheng Yang, Siqin Wu, Heyuan You, Shenyan Wu, Xin Wu, and Xuxu Guo. "Simulation-Based Optimisation for Urban Environmental Noise Coupled with Auditory and Visual Subjective Evaluation." Complexity 2020 (August 7, 2020): 1–21. http://dx.doi.org/10.1155/2020/6958367.

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Environmental noise has a major negative impact, causing interference for people to communicate, rest, sleep, and general annoyance. In order to control urban environmental noise, simulation-based optimisation for urban environmental noise is conducted. On the basis of the current acoustic environment of Zhaohui Campus of Zhejiang University of Technology, three optimisation plans that include noise barrier optimisation, greenbelt optimisation, and a combination optimisation of noise barrier and greenbelt are proposed. These scenarios are simulated using NoiseSystem software to obtain their ability to reduce noise and determine auditory perception by using different control measures. To determine the visual perception of the optimisation plan, 100 people of different age groups were randomly selected, and each person scored the noise barrier and the greenbelt in the simulated scenarios. Results of the comprehensive evaluation of auditory and visual perception show that noise barriers can provide better auditory feelings, but greenbelts can provide a better auditory and visual subjective experience. Therefore, in addition to the application of noise control measures, their visual design must be fully considered. Moreover, the visual perception of plants is stronger than that of others.

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Laxmi, Vijaya, Chaitanya Thakre, and Ritesh Vijay. "Evaluation of noise barriers based on geometries and materials: a review." Environmental Science and Pollution Research 29, no. 2 (October 27, 2021): 1729–45. http://dx.doi.org/10.1007/s11356-021-16944-2.

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10

Daigle, G. A., Y. Gabillet, and A. L’Esperance. "Experimental and theoretical evaluation of outdoor noise barriers including propagation effects." Journal of the Acoustical Society of America 90, no. 4 (October 1991): 2305–6. http://dx.doi.org/10.1121/1.402354.

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11

Pereta, Karol, Lucjan Janas, and Rafał Klich. "Evaluation of efficiency of acoustic screen with gate." Budownictwo i Architektura 13, no. 4 (December 9, 2014): 185–94. http://dx.doi.org/10.35784/bud-arch.1763.

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One of the biggest problems of traffic noise protection is the proper design of noise barriers, their location, length and height. An experimental and analytical efficiency method of traffic noise protection against traffic noise, in the case of a single-family building, has been presented in this paper. The efficiency of this screen has been evaluated by an indirect method. In this case research survey on site has been made. The calculations have been made with the use of three methods. The results of measurements and calculations have been compared. A low efficiency acoustic screen has been demonstrated, whereas its low efficiency mainly resulted from the low height and length. On the basis of the interviews with residents, it can be said that the construction of screens, even those of low efficiency, makes sense.

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12

Ang, Linus, Yong Koh, and Heow Lee. "Plate-Type Acoustic Metamaterials: Experimental Evaluation of a Modular Large-Scale Design for Low-Frequency Noise Control." Acoustics 1, no. 2 (April 1, 2019): 354–68. http://dx.doi.org/10.3390/acoustics1020019.

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For industrial applications, the scalability of a finalised design is an important factor to consider. The scaling process of typical membrane-type acoustic metamaterials may pose manufacturing challenges such as stress uniformity of the membrane and spatial consistency of the platelet. These challenges could be addressed by plate-type acoustic metamaterials with an internal tonraum resonator. By adopting the concept of modularity in a large-scale design (or meta-panel), the acoustical performance of different specimen configurations could be scaled and modularly combined. This study justifies the viability of two meta-panel configurations for low-frequency (80–500 Hz) noise control. The meta-panels were shown to be superior to two commercially available noise barriers at 80–500 Hz. This superiority was substantiated when the sound transmission class (STC) and the outdoor-indoor transmission class (OITC) were compared. The meta-panels were also shown to provide an average noise reduction of 22.7–27.4 dB at 80–400 Hz when evaluated in different noise environments—traffic noise, aircraft flyby noise, and construction noise. Consequently, the meta-panel may be further developed and optimised to obtain a design that is lightweight and yet has good acoustical performance at below 500 Hz, which is the frequency content of most problematic noises.

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TAKIMOTO, Shin, Hiroki MATUMOTO, and Kenichi SAITO. "114 Evaluation of The Attenuation Effect of Noise Barriers with Varied Shape." Proceedings of Conference of Hokkaido Branch 2007.46 (2007): 27–28. http://dx.doi.org/10.1299/jsmehokkaido.2007.46.27.

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14

Wijnant, Ysbrand, Judith L. Rochat, Bart Willems, and Wout Schwanen. "A FEM/Kirchhoff-Helmholtz integral model for noise diffractors on low height noise barriers." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 5 (August 1, 2021): 1455–61. http://dx.doi.org/10.3397/in-2021-1846.

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So-called noise diffractors are a novel way to reduce traffic noise. As opposed to blocking or absorbing noise, diffractors bend noise in an upward direction, creating a shadow zone of reduced noise levels behind the diffractor. The diffraction is most effectively induced by quarter-wavelength resonators. The resonators can be placed in the ground but can also be mounted on top of a (low height) noise barrier, which provides additional reduction. In this paper, we describe a finite element/Helmholtz integral model for a diffractor mounted on a low height noise barrier. The finite element model is used to calculate the scattered acoustic field in the proximity of the diffractor for a noise source sufficiently far away from the diffractor. The acoustic pressure and particle velocity on the outer boundary of the finite element domain are subsequently used in the Kirchhoff-Helmholtz integral formulation to evaluate the acoustic field in the far field. The major benefit of this approach is a large reduction of the model size and reduced calculation times. This allows us to assess the reduction values at different barrier heights, larger distance from source to diffractor and larger distances from diffractor to evaluation points, with an example shown for highway traffic noise.

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15

Van Renterghem, T., and D. Botteldooren. "Numerical evaluation of tree canopy shape near noise barriers to improve downwind shielding." Journal of the Acoustical Society of America 123, no. 2 (February 2008): 648–57. http://dx.doi.org/10.1121/1.2828052.

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16

Peiró-Torres, M. P., M. Ferri, Luis M. Godinho, Paulo Amado-Mendes, Francisco Jose Vea Folch, and Javier Redondo. "Normal incidence sound insulation provided by Sonic Crystal Acoustic Screens made from rigid scatterers – assessment of different simulation methods." Acta Acustica 5 (2021): 28. http://dx.doi.org/10.1051/aacus/2021021.

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Sonic crystal acoustic screens have been in progressive research and development in the last two decades as a technical solution for mitigating traffic noise. Their behaviour is quite different from that observed in classical barriers, with the latter being based on physically blocking the direct sound propagation path (only allowing diffracted noise to reach sensible receivers), and sonic crystals providing attenuation efficiency based on the creation of “band-gaps” at specific frequency ranges, due to the Bragg’s interference phenomenon. The distinct physical mechanisms of these two types of noise barriers complicates the use of classical simplified or even numerical models developed for traditional barriers to simulate and predict the attenuation performance of a sonic crystal, and alternative methods become thus required. In the acoustics scientific literature, several authors have proposed estimation and simulation methods based on different numerical tools to predict the sound insulation provided by these new noise abatement solutions. This paper presents a comparative evaluation of some of these methods, with emphasis on the assessment of their accuracy versus memory usage in order to determine which one is the most suitable for optimization methodologies in the design of new devices with improved acoustic performance.

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17

Rubáš, Pavel. "Confusion in the evaluation of sound barriers under harmonized standard." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 4 (August 1, 2021): 2318–26. http://dx.doi.org/10.3397/in-2021-2105.

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After the obligatory introduction of the declaration of uncertainty in EN 1793-2:2018, the B categories shall not be used to prevent further confusion. Contrary to the updated standard, B categories remain a ubiquitous contractual criterion in the Czech Republic. Contractors continue to request insulation category B3 products determined according to the cancelled EN 1793-2:1997. The current standard only specifies a test method for determining the intrinsic airborne sound insulation performance of noise barriers designed for tunnel roads, deep trenches or covered spaces. EN 1793-6:2018 shall be used for barriers designed for non-reverberant conditions. Notified bodies involved in barriers testing should exercise care and analyze whether supporting test standards in the cancelled but still harmonized EN 14388:2005 can be used or whether the latest testing procedures will be considered. A guidance document is vital because the situation is becoming increasingly confusing. Common rules should be established across the EU to prevent invalid contractual requirements concerning B3 category barriers designed for non-reverberant conditions. The paper analyzes the current unsatisfactory situation, discusses the application of single number rating involving uncertainties, and proposes decision rules for logical and illogical contractual requirements.

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Argo, Theodore F., Andrew D. Brown, David J. Audet, Nathaniel Greene, Caylin R. McCallick, Carol A. Sammeth, David A. Anderson, and Gregory T. Rule. "Methods for validation of electromechanical evaluation of hearing protection." Journal of the Acoustical Society of America 151, no. 4 (April 2022): A216. http://dx.doi.org/10.1121/10.0011097.

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Preventing hearing injury while maintaining situational awareness is of critical importance while using hearing protection devices (HPDs). Determining the optimal HPD for such varied conditions as operating machinery, riding in aircraft, and using firearms is a non-trivial task. Currently, the Noise Reduction Rating (NRR) is the only required HPD specification; other important characteristics of advanced HPDs are not reported in a standardized manner despite the availability of relevant test standards. Barriers to standardized performance reporting are the use of human subjects and the range of performance capabilities of commercially available HPDs. To complement existing test standards and support standardization of performance reporting across a broader range of performance capabilities, a suite of quantitative, sensor-based tests is being developed to quickly, inexpensively, and comprehensively evaluate candidate HPDs. The five-test battery evaluates signal quality, sound localization, level-dependent frequency response, electronic self-noise, and impulse noise response. In parallel, a set of human subject tests is being developed to validate the electromechanical metrics. Here, we will present (1) preliminary results comparing human performance with complementary electromechanical data and (2) a software tool under development incorporating the electromechanical tests to optimize HPD selection for application-specific hearing protection.

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19

Gužas, Danielius, Sergej Anashko, and L. Gogolashvili. "Investigation into the Properties of New Materials Having a Possible Effect on the Evaluation Parameters of Sound Insulation and Absorption." Solid State Phenomena 220-221 (January 2015): 55–59. http://dx.doi.org/10.4028/www.scientific.net/ssp.220-221.55.

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The efficiency of creating and designing noise reduction measures greatly depends on physical, chemical, mechanical and other properties of the selected materials. Some of them and sometimes all of those have a big impact on the general sound insulation of designed measures that also include absorption values predetermining their efficiency.As has been known for a long time, the formed heavy partitions and elements acquire increased sound insulation according to the law of mass, i.e. the heavier is the weight per m2 of the surface (kg/km2), the higher is the sound of insulation.To increase the efficiency of noise reduction in barriers, it is necessary to search for some other properties of the material like design, quality, etc.The article describes how calculations and empirical manipulations facilitate finding an optimal complex construction effectively reducing noise.

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20

Birle, E., M. Melsbach, and D. Heyer. "Evaluation of the performance of a drainage geocomposite in a simple cover system based on 10 year measurements." IOP Conference Series: Materials Science and Engineering 1260, no. 1 (October 1, 2022): 012018. http://dx.doi.org/10.1088/1757-899x/1260/1/012018.

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Abstract In the course of the geotechnical investigations for a new runway at Munich Airport the hydro-mechanical behaviour of organogenic clays was studied. With the aim of an efficient use of materials the organogenic clay shall be used for noise and view barriers. As the organogenic clays have increased arsenic contents the percolation of such structures should be minimized. For the detailed investigation of the hydro-mechanical behaviour and for the determination of seepage quantities, a large scale, 5 m high, 30 m long and 25 m wide test fill was constructed. Due to the low permeability of the organogenic clays in compacted condition a cover design with a drainage mat and a top layer without an additional sealing layer was chosen. Measurements of the water balance were collected since the installation in 2008. The results show very low leachate quantities, although humid climatic conditions with average annual precipitation of approx. 745 mm were present. The low leachate rates can be mainly attributed to the capillary-breaking effect of the drainage geocomposite and the high water retention capacity of the topsoil. Based on the results the presented simple cover system can be considered an efficient and effective solution for minimizing infiltration water into core materials of embankments and noise barriers in road-way design.

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21

Macek, Daniel, and Matouš Kosina. "Evaluation of Bridge Project Variants from the LCC Perspective." International Journal of Engineering Research in Africa 47 (March 2020): 63–68. http://dx.doi.org/10.4028/www.scientific.net/jera.47.63.

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The lowest purchase price is the easiest criterion in tendering for civil engineering. However, in view of the longevity of these buildings and their social significance, this criterion is insufficient. Renovation and maintenance costs play an important role in the construction life cycle and need to be taken into consideration, too. The structural design clearly influences the operating costs of the building, which can be predicted. The paper presents an example of how to approach this issue. The methodology is focused on bridge structures. The paper presents a software application for the calculation of renovation and maintenance costs which are generated from the following structural elements: abutments, pillars, deck (bearing structure), bearings, bridge deck insulation, drainage, roadway, cornice, railing, crash barriers, expansion joints and noise barriers. The structural elements can be specified in the application in predefined type / material variants. If the user uses material that is not included in the database, this situation is solved by adding the appropriate element to the database. If a combination of materials is used for one component, these materials are defined as separate structural elements. Bridge structures are evaluated over a lifetime of 100 years.

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Kozak, Petr, Ondrej Dasek, Radka Matuszkova, and Michal Radimsky. "Low-Noise Asphalt Pavements in Urban Areas." Applied Mechanics and Materials 858 (November 2016): 282–86. http://dx.doi.org/10.4028/www.scientific.net/amm.858.282.

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Current requirements for the reduction of the noise pollution in inhabited areas are constantly increasing. Acoustic wearing courses represent the real measures how to directly mitigate sources of road traffic noise created by a tire/road contact. Directly reduced noise emissions created by a tire/road contact don't need further mitigation by expensive noise barriers. Noise emissions on two different types of wearing courses of asphalt mixtures (Asphalt concrete for very thin layers and Low-noise stone mastic asphalt) were measured using the specialized device operating on the basis of CPX (Close Proximity method) and compared with the standard mixture of Asphalt concrete. Differences were between 1 dB and 5 dB depending on the wearing course and the vehicle speed. The efficiency of the low-noise asphalt pavements was also compared with the initial costs of the pavements. The economical evaluation confirmed that the initial costs of the acoustic wearing courses are higher than the costs of the standard asphalt concrete mixture. However the noise reduction by 1 dB using the asphalt concrete for very thin layers increases the costs just by 350 USD (considering the same length and width of the road segment), which makes acoustic wearing courses the economically efficient noise reducing measure.

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Zandberga, A., L. Lieplapa, and D. Blumberga. "The Analysis of Noise Level on Saulkarsti Bypass, Latvia." Scientific Journal of Riga Technical University. Environmental and Climate Technologies 3, no. 3 (January 1, 2009): 135–41. http://dx.doi.org/10.2478/v10145-009-0018-3.

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The Analysis of Noise Level on Saulkarsti Bypass, Latvia The environmental impact assessment (EIA) is an acknowledged method in the world used for estimating the possible changes to the environment caused by proposed development activities, including the development of linear infrastructures. The EIA of planned projects for building or reconstruction of the motorways in Latvia are usually carried out in a short time frame, and therefore the data characterizing current environmental conditions sometimes are not of the best quality. These kind of data gaps cause an inaccurate prognoses on the possible changes to environmental quality after project implementation. Our research demonstrates that this was the case concerning the weak evaluation of sound levels on the Saulkrasti bypass. Within the framework of the EIA, the prognosis of sound levels was elaborated, prooving that, generally, the traffic sound will be within the officially permissible levels, although the problem points are recognized and the erection of sound barriers are proposed. After construction of bypass, however, the noise monitoring has not been carried out in order to verify whether the prognosis are true. In fact, the results of experimental measurements at four points on the Saulkrasti bypass showed the opposite - the noise level in the daytime (Ld) exceeded the acceptable value at all points of the measurements, including the places with installed sound barriers. The task of our experimental measurements on the bypass was also to find a correlation between the noise level and traffic intensity. The results showed that a correlation between these factors is weak, and the noise level is not directly dependant on traffic intensity, but on the total impact of several factors.

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Qian, Zhen, Min Chen, Yue Yang, Teng Zhong, Fan Zhang, Rui Zhu, Kai Zhang, et al. "Vectorized dataset of roadside noise barriers in China using street view imagery." Earth System Science Data 14, no. 9 (September 6, 2022): 4057–76. http://dx.doi.org/10.5194/essd-14-4057-2022.

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Abstract. Roadside noise barriers (RNBs) are important urban infrastructures to ensure that cities remain liveable. However, the absence of accurate and large-scale geospatial data on RNBs has impeded the increasing progress of rational urban planning, sustainable cities, and healthy environments. To address this problem, this study creates a vectorized RNB dataset in China using street view imagery and a geospatial artificial intelligence framework. First, intensive sampling is performed on the road network of each city based on OpenStreetMap, which is used as the georeference for downloading 6×106 Baidu Street View (BSV) images. Furthermore, considering the prior geographic knowledge contained in street view images, convolutional neural networks incorporating image context information (IC-CNNs) based on an ensemble learning strategy are developed to detect RNBs from the BSV images. The RNB dataset presented by polylines is generated based on the identified RNB locations, with a total length of 2667.02 km in 222 cities. Last, the quality of the RNB dataset is evaluated from two perspectives, i.e., the detection accuracy and the completeness and positional accuracy. Specifically, based on a set of randomly selected samples containing 10 000 BSV images, four quantitative metrics are calculated, with an overall accuracy of 98.61 %, recall of 87.14 %, precision of 76.44 %, and F1 score of 81.44 %. A total length of 254.45 km of roads in different cities are manually surveyed using BSV images to evaluate the mileage deviation and overlap level between the generated and surveyed RNBs. The root mean squared error for the mileage deviation is 0.08 km, and the intersection over union for overlay level is 88.08 % ± 2.95 %. The evaluation results suggest that the generated RNB dataset is of high quality and can be applied as an accurate and reliable dataset for a variety of large-scale urban studies, such as estimating the regional solar photovoltaic potential, developing 3D urban models, and designing rational urban layouts. Besides that, the benchmark dataset of the labeled BSV images can also support more work on RNB detection, such as developing more advanced deep learning algorithms, fine-tuning the existing computer vision models, and analyzing geospatial scenes in BSV. The generated vectorized RNB dataset and the benchmark dataset of labeled BSV imagery are publicly available at https://doi.org/10.11888/Others.tpdc.271914 (Chen, 2021).

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Yoon, Je Won, Kang Seok Jang, and Yong Thung Cho. "Acoustic Performance Evaluation and Prediction for Low Height Noise Barriers Installed Adjacent To Rails Using Scale Down Model." Journal of the Korean society for railway 19, no. 2 (April 30, 2016): 124–34. http://dx.doi.org/10.7782/jksr.2016.19.2.124.

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Lee, Eon S., Dilhara R. Ranasinghe, Faraz Enayati Ahangar, Seyedmorteza Amini, Steven Mara, Wonsik Choi, Suzanne Paulson, and Yifang Zhu. "Field evaluation of vegetation and noise barriers for mitigation of near-freeway air pollution under variable wind conditions." Atmospheric Environment 175 (February 2018): 92–99. http://dx.doi.org/10.1016/j.atmosenv.2017.11.060.

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Schutte, Debra, Thomas Templin, and Brian Schutte. "MAPPING BARRIERS AND FACILITATORS OF ACCESS TO HEARING HEALTHCARE RESOURCES TO THE COM-B FRAMEWORK." Innovation in Aging 6, Supplement_1 (November 1, 2022): 350. http://dx.doi.org/10.1093/geroni/igac059.1386.

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Abstract Age-related hearing impairment (ARHI) affects 20-40% of older adults. However, many people with hearing impairment fail to seek professional evaluation and treatment, delay seeking treatment, or abandon treatment. The purpose of this study was to identify barriers and facilitators of access to hearing healthcare resources in a rural setting and to characterize these barriers within the COM-B (capability, motivation, and opportunity) framework. Survey packets were handed out following services at a rural community church; 72 completed surveys were returned. The mean age of participants was 54.4 years. Thirty-one percent of respondents reported moderate to severe hearing impairment; of these individuals, 7 (31%) were currently using a hearing aid. Rates of hearing protection use fell below the Healthy People 2020 target of 53% across occupational and leisure noise exposure. Forty-eight percent (N=34) of participants had never had their hearing tested as an adult. Overall perceived barriers were significantly correlated with age (r= .260, P = .034) and perceived hearing loss (r=-.277, P= .025). Barriers were identified across all domains and subdomains of the COM-B framework. Barriers clustered in the reflective motivation domain, in which participants undervalue the significance of hearing loss. Barriers also clustered within the social and physical opportunity domains, suggesting a lack of access to providers and an undervaluation of hearing loss by others (family and health care providers). These findings provide evidence regarding the accessibility of hearing healthcare services in rural settings and will serve as a foundation for the design of a community-tailored hearing health intervention.

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Daigle, G. A., A. L’Espérance, and Y. Gabillet. "Erratum: ‘‘Experimental and theoretical evaluation of outdoor noise barriers including propagation effects’’ [J. Acoust. Soc. Am. 90, 2305 (A) (1991)]." Journal of the Acoustical Society of America 91, no. 3 (March 1992): 1772. http://dx.doi.org/10.1121/1.403812.

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Grubliauskas, Raimondas, та Donatas Butkus. "CHAMBER INVESTIGATION AND EVALUATION OF ACOUSTIC PROPERTIES OF MATERIALS/KAMERINIAI MEDŽIAGŲ AKUSTINIŲ SAVYBIŲ TYRIMAI IR VERTINIMAS/КАМЕРНЫЕ ИССЛЕДОВАНИЯ И ОЦЕНКА АКУСТИЧЕСКИХ СВОЙСТВ МАТЕРИАЛОВ". JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 17, № 2 (30 червня 2009): 97–105. http://dx.doi.org/10.3846/1648-6897.2009.17.97-105.

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Traffic‐generated noise accounts for 60–80% of the noise prevailing in towns. With the aim of reducing the impact of noise on humans, measures and methods of fighting noise in towns and residential areas should be developed. In the majority of cases, noise suppression walls (barriers) are one of the most suitable means in tows to reduce the dispersion of noise to residential territories. Acoustic properties of materials to be used for noise walls were investigated and, on the basis of the obtained findings, the most suitable materials with regard to noise reduction were proposed. A noise‐suppression chamber was designed and installed for the experimental investigation into acoustic properties. Separate materials (fibreglass, wood chipboard, gypsum cardboard, foam polystyrene) were used for the experiment by composing various structures of different modifications. With the aim of evaluating the capacity of different materials to suppress noise, a coefficient was used to evaluate noise suppression in a material thickness measuring unit. Efficiency of the noise reduction structures used in the experiment is described by a separate index. Different materials differently suppress the dispersion of noise of various frequencies, whereas the structures of wood chipboards (10 mm) filled with fibreglass or rock wool are the most efficient in all frequency ranges compared with acoustic properties of other structures used during the experiment. Santrauka 60–80 % miestuose vyraujančio triukšmo kelia transportas. Kad triukšmo poveikis žmogui būtų mažesnis, būtina ieškoti priemonių ir būdų triukšmui miestuose ir gyvenvietėse mažinti. Daugeliu atvejų miestuose vienas iš tinkamiausių metodų tam yra triukšmo slopinimo sienelės (barjerai). Tiriant nustatyta triukšmo sienelėms naudotinų medžiagų akustinės savybės bei, atsižvelgiant į gautus rezultatus, siūlomos triukšmo slopinimo požiūriu tinkamiausios medžiagos. Akustinių savybių eksperimentiniams tyrimams buvo sukonstruota ir įrengta triukšmo slopinimo kamera. Tirta skirtingos medžiagos (stiklo vata, medžio drožlių plokštės, gipso kartono plokštės, putų polistirolas) bei iš jų sudarytos konstrukcijos, panaudojant įvairias modifikacijas. Skirtingų medžiagų geba slopinti triukšmą vertinta nustačius koeficientą. Jį taikant gaunamas garso slopinimas medžiagos storio mato vienete. Bandymuose naudojamų konstrukcijų, skirtų triukšmui mažinti, efektyvumas apibūdinamas tam tikru rodikliu. Įvairios medžiagos skirtingai slopina įvairių dažnių garso sklidimą, o medžio drožlių plokštės (10 mm) konstrukcijos su stiklo arba akmens vatos užpildu tam tinka geriausiai. Palyginti su kitomis bandymuose panaudotomis konstrukcijomis efektyviausiai slopinamas beveik visų dažnių diapazonų garsas. Резюме Основным источником шума в городах, составляющим 60–80% общего шума, является транспорт. В целях снижения шумового воздействия на человека необходимо найти пути и средства уменьшения шума в городах и населенных пунктах. Во многих случаях одним из наиболее приемлемых методов уменьшения распространения шума в городах и жилых районах являются звукоизоляционные экраны. Объектом исследования настоящей статьи были акустические свойства материалов, из которых конструируются звукоизоляционные экраны. Полученные результаты показали, какие из проанализированных материалов наиболее применимы для поглощения шума. Для экспериментального исследования акустических свойств материалов была построена шумопоглощающая камера. Исследовались различные виды материалов (стекловата, прессованные древесные плиты, гипсокартон, пенополистирол), а также их конструкции разной модификации. Акустические свойства материалов эффективно поглощать шум характеризуются определенными индикаторами. Наиболее эффективно поглощающими шум всех диапазонов частот по сравнению с другими материалами оказались конструкции, в которых применялись прессованные древесные плиты.

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Yoon, Je Won, Kang Seok Jang, and Yong Thung Cho. "Acoustic Performance Evaluation of Noise Barriers Installed Adjacent to Rails and Suggestion of Approximation Formula for the Prediction of Insertion Loss." Journal of the Korean society for railway 19, no. 5 (October 31, 2016): 629–37. http://dx.doi.org/10.7782/jksr.2016.19.5.629.

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Zannin, Paulo Henrique Trombetta, Thomas Jefferson Vieira, and Andrei Rei Rodrigues Silveira. "Evaluation of the Acoustic Comfort in University Classrooms, Based on the Brazilian Technical Standard NBR 10152—Use of Noise Mapping and Acoustic Barriers to Counter Noise on a University Campus." Current Urban Studies 09, no. 02 (2021): 238–51. http://dx.doi.org/10.4236/cus.2021.92016.

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Cavallari, Jennifer M., Adekemi O. Suleiman, Jennifer L. Garza, Sara Namazi, Alicia G. Dugan, Robert A. Henning, and Laura Punnett. "Evaluation of the HearWell Pilot Program: A Participatory Total Worker Health® Approach to Hearing Conservation." International Journal of Environmental Research and Public Health 18, no. 18 (September 10, 2021): 9529. http://dx.doi.org/10.3390/ijerph18189529.

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Our objective was to pilot test HearWell, an intervention created to preserve hearing among highway maintainers, by using a participatory Total Worker Health® (TWH) approach to designing, implementing and evaluating interventions. Regional maintenance garages were randomized to control (n = 6); HearWell (n = 4) or HearWell Design Team (n = 2) arms. Maintainer representatives from the HearWell Design Team garages identified barriers to hearing health and collaborated to design interventions including a safety leadership training for managers, a noise hazard management scheme to identify noise levels and indicate the hearing protection device (HPD) needed, and a comprehensive HearWell training video and protocol. These worker-designed interventions, after manager input, were delivered to the HearWell Design Team and the HearWell garages. Control garages received standard industry hearing conservation training. Periodic surveys of workers in all 12 garages collected information on the frequency of HPD use and a new hearing climate measure to evaluate changes in behaviors and attitudes over the study period and following interventions. An intention-to-treat approach was utilized; differences and trends in group HPD use and hearing climate were analyzed using a mixed-effects model to account for repeated measures from individual participants. The HearWell Design Team maintainers reported the highest frequency of HPD use. Hearing climate improved in each group 6 months following intervention implementation, with the largest increase and highest value for the HearWell Design Team workers. The HearWell pilot intervention showed promising results in improving HPD use through a participatory TWH approach to hearing conservation. Furthermore, results suggest that employee participation in hearing conservation programs may be necessary for maximal effectiveness.

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Ramanan, P., K. Kalidasa Murugavel, A. Karthick, and K. Sudhakar. "Performance evaluation of building-integrated photovoltaic systems for residential buildings in southern India." Building Services Engineering Research and Technology 41, no. 4 (October 15, 2019): 492–506. http://dx.doi.org/10.1177/0143624419881740.

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The integration of photovoltaic modules into the building structure is a challenging task with respect to power generation of PV module and the effect of incident solar radiation. The performance of building integrated photovoltaic (BIPV) modules varies depending upon the orientation and azimuth angle of the building. In this work, the year-round performance and economic feasibility analysis of grid-connected building-integrated photovoltaic (GBIPV) modules is reported for the hot and humid climatic regional condition at Kovilpatti (9°10′0′′N, 77°52′0′′E), Tamil Nadu, India. The appropriate mounting structures are provided, to experimentally simulate the performance of GBIPV modules at various orientations and inclination angles (0° to 90°). The result indicated that the optimum orientation for installation of BIPV modules in the façade and walls is found to be east while that for a pitched roof south orientation is recommended. The overall average annual performance ratio, capacity utilisation factor, array capture loss and system losses are found to be 0.83, 23%, 0.07 (h/day), and 0.17 (h/day), respectively. In addition, the economic feasibility of grid connected PV system for residential buildings in Tamil Nadu, India is analysed using HOMER by incorporating both a net metering process and electricity tariff. Practical application: Grid-connected building-integrated photovoltaic system has many benefits and barriers by being installed and integrated into the building structure. The application of GBIPV in building structures and its orientation of installation needs to be optimised before installing into buildings. This study will assist architects and wider community to design buildings facades and roofs with GBIPV system which are more aesthetic and account for noise protection and thermal insulation in the region of equatorial climate zones. By adding as shading devices, they can reduce the need for artificial lighting, and moderate heating or cooling load of the buildings.

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Permana, Asep Yudi, Riskha Mardiana, Nitih Indra Komala Dewi, Rd Vena Ventiany Sumanta, Fanny Muthia Ezzaty, and Puspita Alfira Nareswari. "EVALUATION OF CLASSROOM PERFORMANCE IN THE POST-COVID-19 NEW NORMAL ERA AT THE BUILDING PROGRAM VOCATIONAL HIGH SCHOOL." Journal of Southwest Jiaotong University 57, no. 2 (June 10, 2022): 126–45. http://dx.doi.org/10.35741/issn.0258-2724.57.2.11.

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Covid-19 as a new disease is rapidly spreading worldwide, including in Indonesia. The government immediately took steps to suppress it through: the phase of staying at home, large-scale social restrictions, and the new normal phase. This condition impacts the learning structure in schools by imposing learning from home and limiting 50% of students entering school in rotation. This study aims to determine the readiness of educational infrastructure to adapt to the new normal of social distancing and circulation. The qualitative deductive research method is used to compare the measured data with standardization, analyze spatial configurations, and end with design solutions. Manual Drawing Studio and Digital Studio were chosen because they represent the characteristics of the Vocational High School (SMK) Building Program. The results showed that several indicators did not meet the guidelines for implementing learning after the Covid-19 pandemic: air temperature, noise, and lighting conditions. For this reason, it is necessary to add openings and modify the room configuration as a solution related to the effective use of the room by 40.84% with a distance between chairs of 1.5 meters, using barriers between chairs to block droplets between students and lecturers in the room. For circulation, signage for entry and exit is given, so they do not cross paths. According to new normal conditions, the optimal design studio is expected to achieve comfort and improve the quality of learning while supporting the program to break the chain of the Covid-19 virus.

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Munir, Sirojul, Kudang Boro Seminar, Sudradjat, Heru Sukoco, and Agus Buono. "The Use of Random Forest Regression for Estimating Leaf Nitrogen Content of Oil Palm Based on Sentinel 1-A Imagery." Information 14, no. 1 (December 26, 2022): 10. http://dx.doi.org/10.3390/info14010010.

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For obtaining a spatial map of the distribution of nitrogen nutrients from oil palm plantations, a quite complex Leaf Sampling Unit (LSU) is required. In addition, sample analysis in the laboratory is time consuming and quite expensive, especially for large plantation areas. Monitoring the nutrition of oil palm plants can be achieved using remote-sensing technology. The main obstacles of using passive sensors in multispectral imagery are cloud cover and shadow noise. This research used C-SAR Sentinel equipped with active sensors that can overcome cloud barriers. A model to estimate leaf nitrogen nutrient status was constructed using random forest regression (RFR) based on multiple polarization (VV-VH) and local incidence angle (LIA) data on Sentinel-1A imagery. A sample of 1116 LSU data from different islands (i.e., Sumatra, Java, and Kalimantan) was used to develop the proposed estimation model. The performance evaluation of the model obtained the averaged MAPE, correctness, and MSE of 9.68%, 90.32% and 11.03%, respectively. Spatial maps of the distribution of nitrogen values in certain oil palm areas can be produced and visualized on the web so that they can be accessed easily and quickly for various purposes of oil palm management such as fertilization planning, recommendations, and monitoring.

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Baltrėnas, Pranas, Donatas Butkus, Vytautas Nainys, Raimondas Grubliauskas, and Jurgita Gudaitytė. "EFFICIENCY EVALUATION OF A NOISE BARRIER." JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 15, no. 3 (September 30, 2007): 125–34. http://dx.doi.org/10.3846/16486897.2007.9636920.

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Mechanization of industrial and agricultural production, increase of urban and rural traffic flows, modernization of domestic facilities cause a rapid expansion of acoustic discomfort zones. Since the noise level in any environment is one of the basic factors determining the human comfort indicator, investigation into noise processes is given special attention by researchers. Seaport freight discharge terminals are also connected with noise problems. Noise from AB KLASCO fertilizer discharge terminal of Klaipeda seaport cause great concern to local people. There is a noise barrier installed near the terminal. The present paper describes the efficiency evaluation of the noise barrier according to the noise level measurements performed, modelling of noise spread and mathematical calculations. The investigation was performed with noise measuring equipment Bruel&Kjaer mediator 2260. According to measurements, it is obvious that the noise level in the residential zone is 3–4 dBA above the limits (limits are given in HN 33–1:2003) in the daytime, and by 7 dBA at night. The modelling of noise spread was performed by CadnaA program which allowed to make different models according to variations of the noise level caused by changing conditions.

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Natalicchio, Cortney, Hadi Al-Khateeb, Michael J. Chajes, Zheng Y. Wu, and Harry W. Shenton III. "Model calibration of a long-span concrete cable-stayed bridge based on structural health monitoring data: Influence of concrete variability." Bridge Structures 18, no. 1-2 (September 28, 2022): 45–62. http://dx.doi.org/10.3233/brs-220195.

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Structural Health Monitoring (SHM) systems, in combination with controlled load tests, can provide valuable data for calibrating high fidelity bridge models, which can then be used for evaluating the long-term performance of the bridge, improved load ratings, and permit vehicle evaluation. The objective of this research was to calibrate a 3D model of the Indian River Inlet (IRIB) cable-stayed bridge, using strains recorded by the bridge SHM system during a controlled load test. The bridge was modeled in STAAD-Pro and calibrated using a pre-commercialized software platform that uses a Generic Algorithm to minimize the error between the measured and predicted strains. The calibration parameters were the elastic modulus of groups of the main longitudinal edge girder/deck elements, which once calibrated, could be related to the measured concrete strength of the members. Four different models were investigated, using 6, 10, 14, and 18 parameter element groups of the edge girder members. Of the different models, the 14 and 18 parameter models yielded the best results. The “design” model yielded errors as high as 42% when compared to the measured strains; the error was less than 10% for the majority of measurements for the 14-parameter model. Including the effect of the traffic barriers in the model, the weighted average concrete strength of the calibrated model was within 4% of the measured weighted strength. The calibration was shown to be insensitive to measurement noise and was validated using several unique single and multi-vehicle load cases that were heavier and more offset from the centerline of the bridge. The calibration procedure was able to capture the variability in flexural stiffness of the edge girders due to the variability of the concrete, resulting in significantly better agreement between the live load measured strains and the model predicted strains.

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Kralovanec, Jakub, Frantisek Bahleda, and Martin Moravcik. "State of Prestressing Analysis of 62-Year-Old Bridge." Materials 15, no. 10 (May 17, 2022): 3583. http://dx.doi.org/10.3390/ma15103583.

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Ageing infrastructure leads to the need for a proper assessment and final decisions considering its state. In the case of prestressed concrete structures, knowledge of the residual state of prestressing is the crucial factor. Therefore, reliable diagnostic techniques for determining the residual value of the prestressing force are needed. This information is subsequently used in the process of the quantification of the load-carrying capacity and remaining service life of prestressed concrete structures. The presented paper introduces an evaluation of a monolithic 62-year-old prestressed concrete bridge, which was built in 1959. The assessment was carried out as a result of concerns after exposure of the anchorage area of the bridge, which was executed during the construction of the new system of anti-flood barriers in the town of Banska Bystrica in central Slovakia. Therefore, the diagnostic survey and subsequent determination of the residual prestressing force included the application of the saw-cut method, the structural response method, and the Barkhausen noise technique. Finally, the experimental program supported by numerical analysis provided information about the actual state of prestressing in the bridge. Results of performed analysis suggested that the state of prestressing of the bridge in question does not significantly differ from the expected level of prestressing after 62 years of service. Subsequently, obtained conclusions enabled the determination of the load-carrying capacity for future use in the form of a pedestrian bridge.

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Wang, Honggang, Yujie Du, Yu Feng, Yang Lv, Xiaoming Hu, and Yunsheng Qian. "Effective Evaluation of the Noise Factor of Microchannel Plate." Advances in OptoElectronics 2015 (August 27, 2015): 1–6. http://dx.doi.org/10.1155/2015/781327.

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To improve the noise performance of microchannel plate (MCP), we have presented a method using the sine random signals with Poisson distribution as the noise-excitation for electron source. By using this method, the effective evaluation of noise characteristics of MCP has been implemented through measuring and analyzing its noise factor. The results have demonstrated that the noise factor of filmed MCP is lower than 1.8. Additionally, as the open area ratio and the input electron energy are 72% and 400 eV, respectively, the noise characteristics of unfilmed MCP are improved evidently. Moreover, larger open area ratio, higher input electron energy, and higher voltage across the MCP all can reduce effectively the noise factor within a certain range. Meanwhile, the ion barrier film extends the life of image tube but at the cost of an increased noise factor. Therefore, it is necessary that a compromise between the optimum thickness of ion barrier film, open area ratio, input electron energy, and voltage across the MCP must be reached.

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Donavan, Paul. "Noisy Motorcycles and Barriers and Quieter Pavements for Traffic Noise Abatement: Summaries of Two TQA Workshops." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 2 (August 1, 2021): 4144–53. http://dx.doi.org/10.3397/in-2021-2611.

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In the Technology for a Quieter America report, motorcycles were mentioned three times, once in terms of standard test methods and twice in relation to community noise. In New York City, motorcycles placed in the top 10 bothersome noise sources identified by residents. Although there are regulated levels that manufacturers must meet, complaints about in-service motorcycle noise persist. To address this issue, a round table meeting was held in August 2012 with a broad spectrum of participants representing manufacturers, regulators, and other interested, knowledgeable engineers. In preparation of the TQA report, a workshop entitled Cost-Benefit Analysis (CBA) for Noise Control found that CBA was being applied in the area of traffic noise mitigation in regard to the use of barriers and/or quieter pavement. To address the particular CBA issues for this topic, a workshop was held in January 2014 with state and federal transportation officials and the research team responsible for the National Cooperative Highway Research Program NCHRP Report 738, Evaluating Pavement Strategies and Barriers for Noise Mitigation. The findings of these two meetings are summarized in this paper.

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Seid, K. H., R. C. K. Leung, and G. C. Y. Lam. "Evaluation of barrier performance by direct environmental noise simulation." Journal of the Acoustical Society of America 131, no. 4 (April 2012): 3334. http://dx.doi.org/10.1121/1.4708478.

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Saeedi, Soheila, Hamid Bouraghi, Mohammad-Sadegh Seifpanahi, and Marjan Ghazisaeedi. "Application of Digital Games for Speech Therapy in Children: A Systematic Review of Features and Challenges." Journal of Healthcare Engineering 2022 (April 25, 2022): 1–20. http://dx.doi.org/10.1155/2022/4814945.

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Introduction. Treatment of speech disorders during childhood is essential. Many technologies can help speech and language pathologists (SLPs) to practice speech skills, one of which is digital games. This study aimed to systematically investigate the games developed to treat speech disorders and their challenges in children. Methods. A comprehensive search was conducted in four databases, including Medline (through PubMed), Scopus, Web of Science, and IEEE Xplore, to retrieve English articles published by July 14, 2021. The articles in which a digital game was developed to treat speech disorders in children were included in the study. Then, the features of the designed games and their challenges were extracted from the studies. Results. After reviewing the full texts of 69 articles and assessing them in terms of inclusion and exclusion criteria, 27 articles were included in the systematic review. In these articles, 59.25% of the games had been developed in English language and children with hearing impairments had received much attention from researchers compared to other patients. Also, the Mel-Frequency Cepstral Coefficients (MFCC) algorithm and the PocketSphinx speech recognition engine had been used more than any other speech recognition algorithm and tool. In terms of the games, 48.15% had been designed in a way that children could practice with the help of their parents. The evaluation of games showed a positive effect on children’s satisfaction, motivation, and attention during speech therapy exercises. The biggest barriers and challenges mentioned in the studies included sense of frustration, low self-esteem after several failures in playing games, environmental noise, contradiction between games levels and the target group’s needs, and problems related to speech recognition. Conclusion. The results of this study showed that the games positively affect children’s motivation to continue speech therapy, and they can also be used as the SLPs’ aids. Before designing these tools, the obstacles and challenges should be considered, and also, the solutions should be suggested.

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Yoon, Jewon, Chulhwan Kim, Woongyong Lee, Hyejin Kang, and Jooweon Lee. "Parameter analysis and Reliability Evaluation of Road Traffic Noise Prediction Model for Highway Traffic Noise Evaluation." Journal of Korean Society of Environmental Engineers 44, no. 8 (August 31, 2022): 267–75. http://dx.doi.org/10.4491/ksee.2022.44.8.267.

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The purpose of this study is to evaluate the reliability of prediction models(KHTN, RLS-90, CRTN, NMPB-08) that are widely used in road traffic noise analysis. For this purpose, the accuracy and difference values of the prediction model were analyzed by comparing the measurement values performed at the total of 21 highway sites, reflecting various conditions such as road structure, road pavement type, and noise barrier installation. In addition, the correlation between commercial programs(SoundPlan, CadnaA) was compared and reviewed for each of the same prediction models. First of all, as a result of analyzing the accuracy of each prediction model, KHTN is rated as 92.8% the most accurate based on ±3 dB error range. And CRTN is rated as 74.0~76.8% the most accurate among prediction models inherent in commercial programs. And, as a result of analyzing the correlation between commercial programs for prediction models, CRTN is 100% highly correlated and NMPB has the lowest correlation by 69.6%.

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Vacek, Vítězslav, and Jan Holub. "Options of Assessment of Absorption Capacity of Noise Barrier." Advanced Materials Research 923 (April 2014): 125–29. http://dx.doi.org/10.4028/www.scientific.net/amr.923.125.

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The contribution deals with the possibilities of measuring the sound absorption coefficient of concrete panels. On the example of the modified concrete shows one of the possible methods that could be used to check for changes in the case of acoustic properties of restoration of the damaged panels. The issue of evaluation of the sound absorption coefficient is quite complex and difficult in the interpretation of the results, primarily due to the impact of the size of the tested element and parasitic interference in the surrounding environment.

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Arghir, Mariana, Dan Borza, Florin Blaga, Tiberiu Vesseleny, Geamilia Solea, and Mariana Runcan. "Evaluation models for the noise diminution due to the phonique barrier walls." Journal of the Acoustical Society of America 123, no. 5 (May 2008): 3029. http://dx.doi.org/10.1121/1.2932675.

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Tokunaga, Munemasa, Masamichi Sogabe, Tetsuo Santo, and Kiyoshi Ono. "Dynamic response evaluation of tall noise barrier on high speed railway structures." Journal of Sound and Vibration 366 (March 2016): 293–308. http://dx.doi.org/10.1016/j.jsv.2015.12.015.

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SATO, Daigo, Tadashi TOYOHARA, Yukio ABE, Kenjiro YAMAMOTO, and Yuta NAKAMURA. "Evaluation of Acoustic Performance of New Steel Noise Barrier for Railway Viaducts." Proceedings of the Symposium on Environmental Engineering 2022.32 (2022): 2106–11. http://dx.doi.org/10.1299/jsmeenv.2022.32.2106-11-06.

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Yoon, Je-Won, Yong-Thung Cho, Kang-Seok Jang, and Young-Chan Kim. "Acoustic performance evaluation method of the resonance type noise reduction device installed on the top of noise barrier." KIEAE Journal 17, no. 6 (December 31, 2017): 267–72. http://dx.doi.org/10.12813/kieae.2017.17.6.267.

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Lee, Jaiyeop, and Ilho Kim. "Evaluation of Reduction in Reflection Sound bound from a Shaped Noise Barrier Panel." International Journal of Highway Engineering 17, no. 5 (October 15, 2015): 19–24. http://dx.doi.org/10.7855/ijhe.2015.17.5.019.

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Siu‐Kit, Lau, and Kwok‐Wai Lam. "Evaluation of the newly developed equation for noise barrier within an enclosed space." Journal of the Acoustical Society of America 125, no. 4 (April 2009): 2735. http://dx.doi.org/10.1121/1.4784528.

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