• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.709-711
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• 2011

• Journal of the Korea Institute of Building Construction
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• v.15 no.1
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• pp.123-131
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• 2015

The purpose of this study is to analysis the noise characteristics about noise type, sound level, and noise occurrence frequency of living noise in residential buildings. The field measurement was conducted to classify the types of living noise and to examine the actual states of noise occurrence for each living noise source. Among the 24 types of living noise, 10 noise sources were selected based on the loudness and frequency of each living noise. The result indicated that 10 noise sources show the difference on each noise occurrence characteristic by time zones. Therefore, to reduce noise, a management plan should be introduced based on the actual state of the noise occurrence, considering the individual noise source and the time slot during noise frequently occurs. Moreover, the noise standard for each noise types of living noise should be specificated and the education for residents about characteristics of living noise types should be conducted to improve the consciousness of residents.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.9-11
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• 2021

Currently, the occurrence of floor noise in Korea is gradually increasing, and for this reason, the problem of secondary conflict is also increasing. Various studies have been conducted to solve these problems, but the definition of floor noise is not clear, and data of floor noise in various situations cannot be obtained. Therefore, this paper defines various scenarios of floor noise for floor noise epicenter recognition system. For this, the experimental scenario is defined in consideration of environment required for the experiment, the type of floor noise generated in real life, the location of the collector, and the noise intensity. It is possible to increase the accuracy of the floor noise epicenter recognition system when performing data collection and learning operations based on the defined experimental scenario.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.400-409
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• 1994

To investigate the noise attenuation effects of various vegetation configurations, noise levels on 6 study sites along relatively heavy traffic roads were measured. The differences between noise level measures at 1m and 10m spots from the road range from 10 to 15dB depending upon the attributes of the vegetation. When flat grass land was set to control plot, the maximum noise attenuation at 10m spot was measured at the densely planted shrubs with 5dB difference. The areas on upward slope from the road showed the least attenuation effects. Based on the study results, an appropriate setting for low level residential area noise buffer belt would be densely planted shrubs with at least 3m width and 2m height. To be effective, 3m width soft areas covered with grasses are needed at the front and behind sides of the belt. More than 15dB of the noise level caused by the road traffic would be attenuated with the prescription.

• Journal of Sasang Constitutional Medicine
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• v.8 no.1
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• pp.337-347
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• 1996

The 73 outpatients who had been treated in the Oriental Medical Hospital at Dong Eui Medical Center have participated in this study. The following conclusions were made in comparison with the type of disease and symptom and sasang constitution classification. (in the field of questionnaire analysis) 1. The symptom of "weight loss" is significant differences in sasang constitution classification. The frequency of Taeeum goup is more than Soyang group and Soeum group. 2. The symptom of "vomitig" is significant differences in sasang constitution classification. The frequency of Taeeum goup is more than Soyang group and Soeum group. 3. The symptom of "hoarseness" is significant differences in sasang constitution classification. The frequency of Soeum goup is more than Soyang group and Taeeum group. 4. The symptom of "respiratory distress" is significant differences in sasang constitution classification. The frequency of Taeeum goup is more than Soyang group and Soeum group. 5. The symptom of "arthralgia" is significant differences in sasang constitution classification. The frequency of Soyang goup is more than Taeeum group and Soeum group. 6. The symptom of "menstrual pain" is significant differences in sasang constitution classification. The frequency of Soeum goup is more than Soyang group and Taeeum group. 7. The analysis of past history and sasang constitution classification didn't show any significant differences. Only the analysis of past history and age show significant differences. I think that it is necessary to go deep into the clinical study of the type of disease and symptom according to sasang constitution classification.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.291-292
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• 2011

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.480-486
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• 2007

The subway is a necessary public transportation in big cities, which many citizens are using now. However, the demands for subway inner circumstance by citizens are growing recently. Among them, the noise problem is the hot issue to be solved. So, in this study we classified the characteristics of subway noise using the classification and regression trees (CART) based on noise level data in line No. 5 in Seoul. After that We developed the models for effect of subway noise and analyzed the characteristics through it. The result of this study is that we need to consider the type of geometry design and operational factors when the problem of subway noise improves, because the factors which weigh with subway noise are different by type of geometry and operational part.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.256-261
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• 2018

There are three types of noise generated inside the vehicle: BSR (Buzz, Squeak, Rattle). In this paper, we propose a classifier that automatically classifies automotive BSR noise by using features extracted from deep convolutional neural networks. In the preprocessing process, the features of above three noises are represented as noise-map using STFT (Short-time Fourier Transform) algorithm. In order to cope with the problem that the position of the actual noise is unknown in the part of the generated noise map, the noise map is divided using the sliding window method. In this paper, internal parameter of the deep convolutional neural networks is visualized using the t-SNE (t-Stochastic Neighbor Embedding) algorithm, and the misclassified data is analyzed in a qualitative way. In order to analyze the classified data, the similarity of the noise type was quantified by SSIM (Structural Similarity Index) value, and it was found that the retractor tremble sound is most similar to the normal travel sound. The classifier of the proposed method compared with other classifiers of machine learning method recorded the highest classification accuracy (99.15 %).

• The Journal of the Acoustical Society of Korea
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• v.21 no.5
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• pp.485-493
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• 2002

Broadband interference patterns are studied using ship as an acoustic source in shallow waters with varying bathymetry. Waveguide invariant index (β) indicating the pattern of constructive (or destructive) interference in range-frequency domain is derived in a waveguide with constant bottom slope based on adiabatic mode theory. Using this invariant, changes of the interference patterns resulting from the variation of bottom bathymetry are analyzed. Results of the analytic interpretation is compared with those from sea experiments and numerical simulations.

• Elastomers and Composites
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• v.49 no.2
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• pp.95-102
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• 2014

The noise between floors of apartment has been hot issue nowadays. In order to improve the noise insulation performance, we proposed the antivibration rubber system which can be applied to the floor system for sound insulation. Among various types of elastomer, butyl rubber showed the good aging characteristic, low rebound resilience and high damping factor. Thus, the butyl rubber was selected as a basic rubber for antivibration rubber system. The effects of type and loading amounts of carbon black on antivibration properties of butyl rubber were studied. The increase of surface area and the content of carbon black resulted in high bound rubber fraction, high mechanical property, low rebound resilience, and high damping factor of butyl rubber. Based on the results of this study, the new antivibration rubber was prepared and applied to the floor system for sound insulation. The impact sounds of floor system proposed in this study were 40 dB and 43 dB in cases of light weight and heavy weight impact sound, respectively.