• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.253-258
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• 2001

Floor impact noises in apartment buildings have been investigated as they are most annoying in living environment. Several experiments were undertaken to compare perceived noisiness of floor impact noises generated by bang and tapping machine along with children's jumping and running. Results show that bang noise is more annoying than tapping noise and floor impact noise generated by children is less annoying than the noise generated by machine. The floor impact noise generated by children's jumping and running corresponds well with the bang-machine noise in terms of loudness, unbiased annoyance, ${\Phi}$$\_$0/ and IACC. The noise generated by children is somewhat different from machine noise; in spatial impression the real noise is similar to tapping-machine noise but is less annoying that the machine noises.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.904-908
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• 2008

As the various industrial production machinery has come into being by development of industrial technology, the productivity of the basic industrial production machinery has improved and the international competitiveness of the one of Korea has strengthened. However, at the same time, noise from various industrial production machinery disturbs the quiet environment. There are 35 kinds of the noise emission machinery defined in the noise and vibration control act according to the horse power and the number of machinery. These were classified in 1992 through investigation from 1990 to 1991, and the characteristic of the noise emission machinery may be different from the past one. So we need to investigate the characteristics of the noise emitted by machinery to control it rightly. Also we need to investigate the new noise emission machinery which has come into being recently. In this survey, we measured sound intensity of 32 noise emission machinery to calculate the sound power levels of those and investigated the characteristic of the sound power level of those according to the frequency. From the survey, we found that the forging machine, concrete pipe and pile making machine, sawing machine, etc. are the noisy machinery. And the automatic packing machine, sewing machine, centrifuge, etc. are the silent machinery. Also the generator, the concrete pipe and pile making machine, the printing machine, etc. emit the low frequency noise, and the molding machine, the stone cutter, the metal cutter, etc. emit the high frequency noise. Lastly, we intented to propose the proper guide line of classifying noise emission machinery.

• International Journal of Internet, Broadcasting and Communication
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• 제13권2호
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• pp.7-13
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• 2021

Machine vision is a technology that helps the computer as if a person recognizes and determines things. In recent years, as advanced technologies such as optical systems, artificial intelligence and big data advanced in conventional machine vision system became more accurate quality inspection and it increases the manufacturing efficiency. In machine vision systems using deep learning, the image quality of the input image is very important. However, most images obtained in the industrial field for quality inspection typically contain noise. This noise is a major factor in the performance of the machine vision system. Therefore, in order to improve the performance of the machine vision system, it is necessary to eliminate the noise of the image. There are lots of research being done to remove noise from the image. In this paper, we propose an autoencoder based machine vision system to eliminate noise in the image. Through experiment proposed model showed better performance compared to the basic autoencoder model in denoising and image reconstruction capability for MNIST and fashion MNIST data sets.

• 한국소음진동공학회논문집
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• 제20권2호
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• pp.160-165
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• 2010

As the various industrial machinery has come into being by development of industrial technology, the productivity of the basic industrial machinery has improved. However, at the same time, noise from various industrial machinery disturbs the quiet environment. There are 35 kinds of the noise emission machinery defined in the noise and vibration control act according to the horse power and the number of machinery. These were classified in 1992, and the characteristics of the noise emission machinery may be different from the past one. So we need to investigate the characteristics of the noise emitted by machinery to control it rightly. We measured sound intensity of 32 noise emission machinery to calculate the sound power levels of those and investigated the characteristics of the sound power level of those according to the frequency. We found that the forging machine, concrete pipe and pile making machine, sawing machine, etc. are noisy. The generator, the concrete pipe and pile making machine, etc. emit the low frequency noise, but the molding machine, the stone cutter, the metal cutter, etc. emit the high frequency noise.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1990년도 추계학술대회논문집; 한양대학교, 서울; 24 Nov. 1990
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• pp.71-77
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• 1990

This paper describes the experimental analysis of the vibration and noise reduction for the washing machine of the home appliances. For the washing machine, the customers always feel electrical and mechanical noise and vibration. First of all, when the dehydration process is working, the washing machine has nonlinear problems and boundary conditions are varied with time. Therefore these problems are very complicated and difficult to analyze. We verify the sources of the noise and vibration and consider the countermeasure to reduce the noise and vibration level of the washing machine.

• 한국소음진동공학회논문집
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• 제24권9호
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• pp.682-686
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• 2014

Nowadays, the needs to revise the classification criteria for noise emission facilities have been suggested by the related industries. Because there existed many reasonable factors in the criteria regarding the noise emission facilities. And the noise emission facility classification criterion of the print machine changed from 50 HP to 100 HP in 2013. But the increasement of the noise emission facility classification criterion of the print machine can cause adverse effects like the bigger noise. So, in this paper, we measured the print machine's sound power level according to the changes of the print machine's power to assess the adverse effects. The measurement method applied with KS I ISO 9614-2(1996). The corelation between the sound power level and the power of print machines was analyzed by regression analysis. In this paper, we found that the sound power level of the print machines can increase about 1.3 dB in the condition of that the power of print machine increases from 50 HP to 100 HP. And we found that the sound power level of the print machines can increase about 1.0 dB for a increasement of 1,000 SPH(sheet per hour) of printing speed. The noise emission characteristics of print machine stuied in this paper will be useful to design the noise reduction plan in the future.

• 한국기계연구소 소보
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• 통권15호
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• pp.25-35
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• 1985

During one revolution of a gear, the intensity of the gear-meshing noise or vibration will vary, depending upon the run-out in the pitch diameter of the gear. Here noise can be produced bu excentricity of the shaft with respect to the base circle and by pitch errors. According to the noise generated is clearly dependent on the force and the amount of energy expended in elastically straining the machine member. The purpose of this paper is to discuss the analysis of the noise and technical reduction of gear noise for machine tool.

• 대한환경공학회지
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• 제33권10호
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• pp.748-755
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• 2011

1960년대 산업화 이후 기계화가 가속되어 산업발달에 많은 기여를 하였으나 고소음 작업장에서 발생하는 소음피해에 대한 대책은 거의 없는 실정이다. 특히 공장 및 작업장에서 발생하는 기계소음은 반복적으로 되풀이되어 충격적이며, 강한 소음으로 대부분의 현장 작업자들은 높은 불쾌감과 청력장애의 위험을 부담하고 있다. 이러한 관점에서 이 연구는 고소음 작업장에서 발생하는 작업기계 소음을 평가하기 위한 적정 평가어휘를 추출하고자 했으며, 이렇게 추출된 어휘는 작업 기계소음을 평가하기 위한 음향심리 실험 및 기계소음 규제기준 설정을 위한 유용한 자료로 활용될 수 있을 것으로 사료된다.

• 한국소음진동공학회논문집
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• 제23권7호
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• pp.617-623
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• 2013

Accurate prediction of the radiated noise is important to reduce the noise of the washing machine. It is also necessary to predict the excitation force accurately because excitation force can induce noise. In order to predict the excitation force acting on the washing machine, this paper conducts source identification method by use of phase reference spectrum. In this method, the transfer function between the cabinet and the motor through FEM and the measured response from the surface of the cabinet is used. The analysis of the radiation noise from the identified exciting force has been investigated. The comparison between the predicted SPL and the measured SPL at 1m apart from the front side of the washing machine showed good tendency.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.75-81
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• 2006

Recently, customers interest about noise of household electric appliance is growing. so, designer of product must study to reduce noise of product. Specially, in case of household electric appliance such as washing machine, there was consumers' complaint about noise that is radiated under dehydrating condition. But, in the case of washing machine, identification of noise source is not easy when washing machine is under dehydrating condition. Because various noise source influence each other, it is difficult to find out pure contribution degree about output noise. Multi-Dimensional Spectral Analysis(MDSA) is method that can remove correlation between inputs each other and express pure contribution degree about output of single input. So in this study, we analyzed contribution of each noise source on transfer pass of noise that is radiated at dehydration of washing machine using MDSA.