• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.1067-1070
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• 2003

The effects of traffic noise are a serious concern in many urban communities throughout the world. Environmental noise at high intensities directly affects human health by causing hearing loss and indirectly affects human welfare by interfering with sleep, thought, and conversation. In general, portland cement concrete(PCC) pavement is known to create more noise than asphaltic surfaces though it has the advantage of durability and superior surface. However, the results of preliminary laboratory test showed exposed aggregate concrete(EAC) have an effect on reducing traffic noise. Based on the laboratory test, pilot construction of exposed aggregate concrete was performed and series of in-situ measurements were conducted for noise analysis which included the pass-by noise measurement and the close-proximity method. Conclusively, It is expected that tire/pavement noise which is represented much noise levels at higher frequencies would be significantly reduced on special textures of pavement as like exposed aggregate concrete.

• Journal of Advanced Navigation Technology
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• v.24 no.5
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• pp.329-342
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• 2020

In this paper, we analyzed the requirements for the application of UAM, a new concept to solve the traffic congestion in large cities. First, the current domestic and foreign status of research and development related to UAM was investigated and the pros and cons and the time required for each mission radius were analyzed for various configurations of aircraft being commercialized. In addition, in order to analyze the market acceptance of the UAM, the individual's consciousness and reliability requirements were identified and safety requirements were analyzed through accident rate data for each aircraft type. Because it operates in a densely populated urban area, requirement analyses on noise and exhaust, which are environmental factors that can affect the community were performed, and requirements related to aircraft performance, certification standards, and airworthiness standards of FAA and EASA were also analyzed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.5
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• pp.130-145
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• 2021

As part of the Smart Seoul policy, the importance of using big urban data is being highlighted. Furthermore interest in the impact of transportation-related urban environmental factors such as PM10 and noise on citizen's quality of life is steadily increasing. This study established the integrated DB by matching IoT big data with transportation data, including traffic volume and speed in the microscopic Spatio-temporal scope. This data analyzed the impact of a spatial unit in the road-effect zone on environmental risk level. In addition, spatial units with similar characteristics of road traffic and environmental factors were clustered. The results of this study can provide the basis for systematically establishing environmental risk management of urban spatial units such as PM10 or PM2.5 hot-spot and noise hot-spot.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.324-329
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• 2010

The surroundings around subway are becoming more lively for project of CBD (an redevelopment project), however vibrations which are made through passing train cold spread buildings around. The structure-borne noise could be generated at the same time that makes people including developers and th citizens have negative viewpoint on railway. Especially, Seoul Metro 1-4 lines ar built alongside the road nearby houses and business district. That could make plenty of public resentments because of the structure-borne noise. Seoul Metro should make active alternative plans for their future urban environment projects which will be conducted. The case was Railway Facility which were conducted to minimize structure-borne noise from sharp curved track section (4 line, Sinyongsan~Ichon, R 250m). The section is adjacent to house district as near as 6.6m related with pusing international city project, the 4th urban environment project around international building, near Yongsan station. The interval of sleepers would be downsized in half with breaking existing case, and pad stiffness is reduced 4 ton from 10 ton. That makes structure-borne noise minimized because of vibrations are lowered about 19.1-23.0db. The structure above has remained for a year and a half from October, 2008, and had not any trouble to perform excellence with 80million ton rail accumulated tonnage.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.415.2-420
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• 1998

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.782-785
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• 2004

In the Well-being age, many people use a city park for rest deeply think and constitutional walk. The city park is located at near side by traffic road in urban. Citizens are not satisfied with it's fuction as a haven of peace due to road traffic noise. Thus, this study is for a research on the actual noise condition of a city park in Nowon go. This study uses a prediction method called ASJ-model in order to calculate PWLs of road traffic noise. Using calculated PWLs, noise levels in a park are predicted and compared with measured values.

• Korean Journal of Remote Sensing
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• v.22 no.4
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• pp.275-284
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• 2006

The noise sources of a Hyperion image are mainly due to the atmospheric effects, the sensor's instrumental errors, and A/D conversion. Though uncalibrated, overlapping, and all deep water absorption bands generally are removed, there still exist noisy bands. The visual inspection for selecting clean and stable processing bands is a simple practice, but is a manual, inefficient, and subjective process. In this paper, we propose that the extrema ratio be used for noise estimation and unsupervised band selection. The extrema ratio was compared with existing SNR and entropy measures. First, Gaussian, salt and pepper, and Speckle noises were added to ALI (Advanced Land Imager) images with relatively low noises, and the relation of noise level and those measures was explored. Second, the unsupervised band selection was performed through the EM (Expectation-Maximization) algorithm of the measures which were extracted from a Hyperion images. The Hyperion data were classified into 5 categories according to the image quality by visual inspection, and used as the reference data. The experimental result showed that the extrema ratio could be used effectively for band selection of Hyperion images.

• Journal of Environmental Impact Assessment
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• v.33 no.2
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• pp.84-98
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• 2024

This study proposed a prediction equation for the estimation of blasting vibaration and blasting noise, utilizing 320 datasets for the blasting vibration and blasting noise acquired during urban blasting works in the Incheon, Suwon, Wonju, and Yangsan regions. The proposed blasting vibration prediction equation, derived from regression analysis, indicated correlation coefficients of 0.879 and 0.890 for SRSD and CRSD, respectively, with an R² value exceeding 0.7. In the case of the blasting noise prediction equation, stepwise regression analysis yielded a correlation coefficient of 0.911 between the prediction values and real measurements for the blasting nosie, and further analysis to determine the constant value revealed a correlation coefficient of 0.881, with an R² value also exceeding 0.7. These results suggest the feasibility of applying the proposed prediction equations when environmental impact assessments or education environment evaluation according to urban development or apartment construction projects is performed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.410-411
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• 2012

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.4
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• pp.462-472
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• 1998

In this paper, considering the Rayleigh fading, the lognormal shadowing, and the man-made noise which is occurred in urban area randomly, the mobile radio channel and the radio propagations are analyzed. The system affected by the noise is compared to other modelings. The fading, shadowing, and background noise are wholly considered to evaluate the mobile radio propagation effectively. For N=0.000001, the outage probability in the absence of noise is $5.264{times}10^{-6}$, in the fading only $3.1796{times}10^{-4}$, and in the presence of noise $6.0{\times}10^{-3}$. The analysis with the presence of noise is very important for the performance evaluation of mobile radio system.