• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.12
• /
• pp.1639-1644
• /
• 2018

Unlike internal combustion engines, electric cars have little engine sound and very quiet, causing the following problems to occur. First of all, pedestrians are a threat to safety because they can't feel the car approaching. The driver is also unable to recognize how fast his car is driving at a certain speed. To solve these problems, electric cars should be artificially created and reused. This paper examines the problems of the Sampling engine sound currently being used and uses the engine sound to produce a sound engine sound for the solution. The sampling engine sound has some limitations in making natural engine sounds. To overcome this problem, we studied two methods of using software synthesizers. They found subtractive synthsizing and wavetable synthsizing, which compared wavetabe synthsizing with actual engine, sampling and subtractive methods to find the most similar to real engine sound. We found that data usage and production cost are more advantageous than sampling method and subtractive syndication method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2012.04a
• /
• pp.208-209
• /
• 2012

This paper describes a comprehensive process and range of design tools and components for providing Improved perception of engine sound for mass production vehicles by the generation of finely tuned engine harmonics.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2017.01a
• /
• pp.267-268
• /
• 2017

인류는 이동수단의 발전으로 많은 편리함을 누리고 있다. 그러나 발전하는 만큼 대기오염의 문제도 증가하고 있다. 이를 해결하기위해 친환경 자동차가 대안으로 떠오르고 있으나, 저속주행시의 엔진음이 미세하여 좁은길이나 골목길 에서의 보행자 교통사고가 증가하고 있다. 이를 해결하기위해 VESS가 개발되었다. 본 논문에서는 보행자 청각 특성을 고려한 가상 엔진음 설계를 제안하였다. 본 연구를 통하여 보행자 사고 예방 및 생명과 재산보호에 도움이 되길 바란다.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.7
• /
• pp.1263-1269
• /
• 2016

Hearing impaired persons are exposed to the danger since they can't be aware of many dangerous situations like fire alarms, car hones and so on. Therefore they need haptic or visual informations when they meet dangerous situations. In this paper, we design a dangerous sound detection engine for hearing impaired. We consider four dangerous indoor situations such as a boiled sound of kettle, a fire alarm, a door bell and a phone ringing. For outdoor, two dangerous situations such as a car horn and a siren of emergency vehicle are considered. For a test, 6 data sets are collected from those six situations. we extract LPC, LPCC and MFCC as feature vectors from the collected data and compare the vectors for feasibility. Finally we design a matching engine using an artificial neural network and perform classification tests. We perform classification tests for 3 times considering the use outdoors and indoors. The test result shows the feasibility for the dangerous sound detection.

• International Journal of Internet, Broadcasting and Communication
• /
• v.9 no.2
• /
• pp.37-41
• /
• 2017

In the development of means of transportation, human beings who walk, ride or ride carriages are now enjoying the benefits of many means of transportation, including bicycles, airplanes, trains, buses, and cars. In the case of automobiles among various means of transportation, there is an advantage that an individual can conveniently move while possessing it. To solve air polution problems at the same time, eco-friendly automobiles such as low-noise, low-pollution, and high-efficiency automobiles have emerged. However, in the case of eco-friendly vehicleJ, engine noise at low speeds is a noise that is unlike existing vehicles and poses a threat to the safety of pedestrians. In this study, virtual engine system has been developed to prevent engine accidents caused by low- The pedestrians are aware of the fact that the vehicle is approaching.

• Proceedings of the Acoustical Society of Korea Conference
• /
• 1994.06a
• /
• pp.662-667
• /
• 1994

This paper presents the design and construction details of a soundproof enclosure for housing 20 KVA diesel generator-set. As the generator had to be installed close to the hospital building, it was desirable to reduce the transmission of noise by housing the generator in such an enclosure. The diesel engine being an air cooled one, it was essential to supply fresh air into the enclosure for its cooling. Forced inflow of air is provided through an inlet duct located in such a way that the incoming fresh air is thrown close to the inlet of cooling fan of the engine. The high velocity air stream, which heats up while passing over the engine head, escapes to the atmosphere through a rectangular outlet duct with enlarges inlet that receives hot air from the engine. The air ducts were designed specially and have been provided with acoustic lining for sound absorption. The masonary enclosure has been provided with double glazed fixed windows and double doors. The exhaust pipe of the engine fitted with a muffler has been taken out through the enclosure wall facing away from the hospital. Acoustic performance studies conducted in terms of attenuation provided by the enclosure at different frequencies have also been presented and discussed. The noise control measures adopted for building the sound-proof enclosure have been found to be quite effective as the noise levels inside the hospital building are now within the acceptable limits.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.8
• /
• pp.1547-1552
• /
• 2017

Unlike diesel locomotives, electric vehicles have various issues because they have very quiet engine sound. For example, pedestrians are exposed to the dangerous electric vehicles on the road because they can not recognize the electric vehicles' sound. Moreover, the driver is unable to recognize how fast driver's car is driving at a certain speed. To solve these problems, electric cars' sound needs to be artificially implemented and played. This paper examines the problems of the previous sampling engine sound approach. In this paper, instead of using sampling sounds, we developed a novel synthesizer algorithm via programming languages as a software. In experimental results, we demonstrated and verified our proposed synthesizer's approach is superior to the previous sampling approach. In addition, through these synthesizer's approach, we highly expect the proposed synthesizer's approach will give safety, convenience and comfort to the electric vehicles' users.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1997.04a
• /
• pp.481-487
• /
• 1997

The development of transportation and construction equipment has required higher engine power and lower operation cost. The sound which the engine emits often degrade the performance of the whole system which adopts that engine. Specially the marine engine requires high restriction on the noise level for the customer's comfort and safety. The noise and vibration of Diesel engine must be carefully considered in the early design step. The double antivibration system is effective to increase the efficiency of antivibration, and the acoustic enclosure for reducing the noise level. 2 DOF model was effective to estimate the antivibration performance, which allows to determine the mass of the engine bed and the specification of the engine mount. The mass distribution of the enclosure system can be considered effectively by using the FEM model. The design contains structurally rigid engine bed by FEM, which is for reducing the influence of the flexible vibration, rubber mount selection as well as the acoustic enclosure design.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11a
• /
• pp.333.1-333
• /
• 2002

This paper suggests the noise reduction method of the engine cooling fan. It was estimated the fannoise contribution at the engine room and identified the noise source at the rotating fan by sound intensity method, first. And it has been developed the program for predicting the noise spectrum of axial flow fan. The radiated acoustic pressure is expressed the discrete frequency noise peaks at BPF and its harmonics and the line spectrum at the broad band by the noise generation mechanisms. In this paper it is shown that the comparison of the measuted and calculaed noise spectra of fn for the validation of the noise predictiong program. And this paper presents the characteristics of a fan noise due to modify the design parameters. Accordingly, it was obtained the design parameter values for noise reduction of fan.

• 한국연소학회:학술대회논문집
• /
• 2004.11a
• /
• pp.206-212
• /
• 2004

It is necessary to consider the stability, economic environmental-friendly problems by the development of the road, supply of the automobile, environmental problem as designing the exhaust system. To reduce the noise and the vibration of the automobile, it is needed to consider the pulsation noise, air current noise, vibration of air pipe which generate the intake and exhaust noise of the automobile. Moreover, the discharge sounds, intake sound, radiation sound, transmitted sound are occurred. To reduce this influence, the variable valve is needed and to control these factors, path transformation muffler and active type muffler are needed. While engine efficiency could be reduced with this transformationand resistance by the pressure, thermal property. In this study, how to design exhaust systems yielding higher condversion efficiency, lower backpressure and optimize the performance. this study is recommended for exhaust system and designers and engineers involved in SI engine exhaust system and it will furnish information for you to design more efficient.