• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.63-69
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• 2015

Recoilless weapons, which lead strong back blast and impulse noise more than 160 dB, have been used in compliance with the regulation of the safety zone for the safe operations. However, the safety zone regulations for the newly developed weapons should be prepared since the existing guidelines do not provide any information concerning the reason for the safety zone. In this study, the outdoor launch tests were performed to collect the data such as noise, pressure and temperature of the back blast. An assessment method using data obtained from launch tests has been proposed to determine the safety zone. The safety zone has been determined with consideration for the following criteria: Impulse noise, temperature and pressure of the back blast and blast angle. As a results, new safety zones for them have been established for the recoilless weapon developed by ADD (Agency for Defense Development). We expect that this research can be used as a guideline for establishing a new safety zone regulation of similar weapon to be developed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.10
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• pp.537-544
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• 2009

On account of the technological development, intelligent building is on increasing where the artificial regulation on indoor environment is possible, thence the concern about those facilities such as water-supply facility, water-heater and drainage facility has becomes higher. However, due to diversification and complicated system of the facility-equipments, the noise generating from such facility equipment is gradually becoming a problem, and since especially equipment noises arising at the machine room frequently infringe into the resident's pleasant living environment with the complex types of an air-borne sound and a structure-borne sound, it is becoming the civil complaint. On such viewpoint, this Study ever observed the characteristics of noise generating from various facility-equipments in the building, and intended to evaluate the facility-noises by use of the valuation index such as PSIL, N, NC, NR. As result of, the facilities noise which happens in the machine room makes normal conversation very difficult due to high sound pressure level. Based on such data, this study is willing to present it as an essential material for establishment an efficient measure against the facility-noises arising at machine room hereafter.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.5
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• pp.407-415
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• 2016

In this paper, an aviation image fusion method is proposed for creating an informative fused image through gray scale images within noise. The proposed method is based on an adaptive guided filter which adjusts regulation parameter of the filter based on peak signal noise ratio (PSNR) in order to behave as an edge-preserving filtering property. Simulation results demonstrate that the proposed method preserves the edge information of the input image and reduces the noise effect while maintaining designed PSNR.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1344-1349
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• 2000

With rapidly industrial development, a railway has become of a main traffic means. But, the railway noise has caused much annoyance for the residents living nearby railway tracks. Therefore, in our country, for established of Quite dwelling environment, execute regulation standard of railway noise from January 1, 2000. Efficiency soundproofing measures, however, are very difficult because of the lack of basic data and insufficiency of the existing research. In this point, this study attempts to survey the characteristics of attenuation and propagation of railway noise in by existence of noise barrier. And this study intends to get the basic data for establishment of a standard about railway noise.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.9
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• pp.1475-1482
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• 2001

Nowadays reduction of gear noise in power transmission is very important, because the noise regulation is severe and demand of customer on noise is increased. To reduce gear noise, it is necessary to understand the noise characteristics of helical gear. In this work, we designed test rig for the study of gear noise and installed in semi-anechoic chamber. By using this rig, sound pressure level is measured under varying rotational speed and torque. The frequency characteristics of helical gear noise on the effect of lead errors and torque are discussed.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.6
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• pp.52-57
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• 2009

This paper presents a low-noise low-dropout linear regulator that is suitable for on-chip integration with RF transceiver ICs. In the bandgap reference, a stacked diode structure is adopted for saving silicon area as well as maintaining low output noise characteristic. Theoretical analysis for supporting the approach is also described. The linear regulator is fabricated in $0.18{\mu}m$ CMOS process. It operates with an input voltage range of 2.2 V - 5 V and provide the output voltage of 1.8 V and the output current up to 90 mA. The measured line and load regulation is 0.04%/V and 0.46%, respectively. The output noise voltage is measured to be 479 nV/$^\surd{Hz}$ and 186 nV/$^\surd{Hz}$ from 100 Hz and 1 kHz offset, respectively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.217-220
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• 2005

Zero tail type mini excavator is small in size and capacity compared with medium or large excavator. Therefore noise and heat problems are major issues in design due to layout of each components such as engine and hydraulic module. It is necessary to assure reduction of noise and vibration in construction machine, due to be enforced regulation for high noise construction machinery at home and abroad. The objective of this study is to provide basic data which is apply to predict noise effect in detail design stage by estimating noise of cabin for zero tail type mini excavator.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.283-287
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• 2012

Recently, Most of diverse noise of vehicles has decreased competitively according to development of the automotive manufacturing technology. Especially, Passenger car manufacturers has been conducting buzz, squeak and rattle(BSR) noise test as a method of the noise evaluation tests to reduce an unpleasant sound from interior parts on the driving the car. The purpose of this paper is to confirm the change of the noise generated in the product after the reliability evaluation. Here by the BSR test procedure used the test regulation of 'G' company.

• Journal of Adhesion and Interface
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• v.3 no.3
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• pp.1-6
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• 2002

We invested which is major one in rubber materials design factors affecting on noise and showed the design guide for low noise tire development in this study. Tire noise and impact noise for rubber sheets were tested at anechoic room. Hardness, tensile and dynamic mechanical properties were also measured using the rubber sheets. A major design factor of rubber materials affecting on the tire noise was hardness or 300% modulus. There was also positive correlation between two properties. Therefore, designing rubber materials to have low hardness or 300% modulus can reduce noise.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.434-437
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• 2006

The expansion joints are installed for connecting the bridge segments. The ambient noise expansion joints are required in domestic market because of regulation on the noise neighboring traffic roads established by ministry of environment. Therefore, field tests for measuring environment noise depending on the types of the expansion joints are carried out in order to examine the effect of expansion joints into the environments. Related geometrical analysis has been performed.