• Journal of Agricultural Extension & Community Development
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• v.31 no.3
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• pp.127-137
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• 2024

In order to manage noise reasonably in a special working environment in agriculture, the existing quantitative evaluation and related influencing factors such as exposure period, frequency, work method, use of protective equipment, and age should be considered together. This study aims to identify the factors influencing noise exposure through the 2022 survey data of the Farmers' Occupational Disease Survey (National Accreditation Statistics No. 143003) conducted by the Rural Development Administration. As a result, it was found that full-time farmers, rice paddy farming, farming for three to five months throughout the year, men in their 60s, 30 to 50 years of experience, and farmers are exposed to the most noise. Through this study, high-risk groups for noise exposure were identified, and protection measures need to be prepared for them in the future.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.752-760
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• 1993

We research ed on the noise control of a head feeding type combine harvester. It is a kind of combine harvester developed in Japan. And at present, it is used by most Japanese farmer. For a head-feeding type combine harvester it is very difficult to determine the sources of noise because it is a combination of reapers and automatic , threshers and several running parts. However we succeeded in finding out the sound sources of combine harvesters and analyzing their sound by the using sound intensity method. The sound intensity Method is a very up-to-date method to measure and analyze Sound Intensity Levels and sound directions at several measuring point sin a specified area. In this research, first a conventional sound level measurement method is used and secondly the sound intensity method. The first method shows a rather great limitation in allowed exposure duration. The second method shows pin-points the engine itself as being the main source of noise, causing sound flows a ross the operator's seat.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.180-183
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• 2002

In this paper, we propose new unsharp masking technique based on the multiscale gradient planes. The unsharp masking technique is implemented as a high-pass filter and improves the sharpness of degraded images. However, the conventional unsharp masking enhances the noise component simultaneously. To reduce the noise influence, we introduce the edge information from the difference of the gradient values between two consecutive scales of the multiscale gradient. The multiscale gradient indicates the presence of image edges as the ratio between the gradients between two different scales by its multiscale nature. The noise reduction of the proposed method does not depend on the variance of images and noises. In experiment, we demonstrate enhancement results for blurred noisy images and compare with the conventional cubic unsharp masking technique.

• 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.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.2
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• pp.28-33
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• 2008

In a scanning electron microscope (SEM), outside acoustic noise causes image noise that distorts observations of the specimen being examined. A SEM that is less sensitive to acoustic noise is highly desirable. This paper investigates the image noise problem by addressing the mode shapes of the base plate and the transmission path of the acoustic noise and vibration. By arranging the position of the rib, a new SEM base plate was developed that had twisting as the 1st and 2nd modes. In those two twisting modes, vibration nodes existed near the center of the base plate where the specimen chamber is placed. Less vibration was transmitted to the chamber and to the specimen by the twisting modes compared to bending ones, which are the 2nd and 3rd modes for a rectangular plain base plate. An SEM with the developed base plate installed exhibited a significant reduction of image noise when exposed to acoustic noises below 250 Hz.

• Journal of the Korean Wood Science and Technology
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• v.46 no.4
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• pp.362-367
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• 2018

This study estimates the sound absorption capability of rice straw particle mats by two methods: the transfer function method and the reverberation room method. In the reverberation method, the central frequency was set to the one-third octave band in the 100-5000 Hz range; in the transfer function method, the frequency range was 500-6400 Hz. Both methods yielded similar noise reduction coefficients of the rice straw mats. The noise reduction coefficient was approximately 0.8, indicating a high sound-absorption property of the mats. Therefore, rice straw matting is a suitable candidate material for sound-barrier walls against highway noise.

• Journal of Animal Environmental Science
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• v.12 no.1
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• pp.21-28
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• 2006

This study was carried out to measure and analyze the characteristics of noise and vibration, and to analyze their effects on the productivity of layers, mechanical troubles, and abnormal wear-out failure of facilities and equipment of the layer house. The measurements of noise and vibration were taken at 13 layer farms nationwide for the operations of feed supplier system, feed distribution system, automatic egg collection system, ventilation system, blot conveyer for layer feces, and fur the case of with and without their operation by a sound level meter and a vibration measuring system in the layer house equipped with upright multi-tier cages. Measurement results showed that normal times were noise(N) 82 dB and vibration(V) 0.2072 cm/s, feed supplier system were 90 dB(N) and 2.8560 cm/s(V), feed distribution system were 90 dB(N) and 2.0222 cm/s(V), automatic egg collection system were 87 dB(N) and 0.1865 cm/s(V), ventilation system 88 dB(N) and 2.5364 cm/s(V), belt conveyer fur layer feces were 88 dB(N) and 0.2387 cm/s(V), and then maximum values of noise and vibration were 90 dB and 2.8560 cm/s, respectively, when feeding systems(feed supplying system and feed distribution system) were operated. Based on these results, an experiment is being conducted to find out the effect of noise and vibration on the productivity of layers in the layer house equipped with upright multi-tier cages.

• Journal of the Korean Mathematical Society
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• v.54 no.3
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• pp.909-943
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• 2017

This paper is devoted to studying abstract stochastic semilinear evolution equations with additive noise in Hilbert spaces. First, we prove the existence of unique local mild solutions and show their regularity. Second, we show the regular dependence of the solutions on initial data. Finally, some applications to stochastic partial differential equations are presented.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.47-55
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• 2009

This study analyzes the correlation between noise and the size of urban forests. Under the assumption that the main cause of the noise m the city is the population density, the size of urban forests per capita and the ratio of urban forests with respect to the size of urban per 100 thousand persons are used for the calculation of correlations with noise. The results of the calculations of Pearson's and Spearman's correlation coefficients indicate that the increase in the size of urban forests has a significant effects in reducing the day-time as well as night-time noise for most regions in the cities. The size of urban forests within public parks has a significantly negative correlation with the noise. However, calculated correlation coefficients imply the increase in the size of total urban forests is more effective in reducing the noise than the increase in the urban forests in public parks.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.526-531
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• 2010

For efficient use of wood, it is important to control moisture of wood in processing wood. Near-infrared (NIR) spectroscopy can be used to estimate the physical and chemical properties of materials quickly and nondestructively. In this study, it was intended to measure the moisture contents on the surface of wood using NIR spectroscopy coupled with multivariate analytic statistical techniques. Because NIR spectroscopy is affected by the chemical components of the specimens and contains signal noise, a regression model for detecting moisture content of wood was established after carrying out several numerical pretreatments such as Smoothing, Derivative and Normalization in this study. It shows that the regression model using NIR absorbance in the range of 750~2,500 nm predicts the actual surface moisture content very well. Near-infrared spectroscopy technique developed in this study is expected to improve a technology to control moisture content of wood in using and drying process.