• 한국소음진동공학회논문집
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• 제25권3호
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• pp.141-149
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• 2015

In this study, there is an investigation about the sound quality of automotive horn that attached to luxury sedans. In order to define a questionnaire of horn sound quality the factor analysis is conducted. Ten automotive horns are selected for this research and ten passenger cars(nine is luxury sedan and one economy class car). Luxury is used for the questionnaire as an attribute for the sound quality of car horn. The interior noises for ten test cars are recorded and used for the subjective analysis of car horn sound. In the paper, new sound metric for the car horn sound is presented. The new sound metric is used for the objective sound index for the prediction of subjective sound quality of car horn.

• 한국음향학회지
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• 제43권1호
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• pp.39-48
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• 2024

자동차용 경음기는 운전자 간의 의사소통 수단이자 보행자에게 사전에 경각심을 불러일으키는 부품으로서 안전상 중요한 역할을 한다. 유한 요소 방법과 전기 회로 모델을 활용한 자동차용 경음기의 모델링 연구와 혼의 음향학적 특성을 분석한 연구들이 수행되었으나, 트럼펫 혼의 작동 주파수 설계 방법에 대한 연구는 미비하다. 본 논문에서는 트럼펫 혼의 진동부가 결정되었을 때, 쉘의 음향 리액턴스에 따른 작동 주파수를 예측하는 설계 방법을 제시하고자 한다. 음향부에서는 지수 혼과 도파관이 결합된 혼에 대해 다루었고, 임피던스 튜브 실험을 통해 도파관의 입구 음향 리액턴스는 해석 결과와 유사함을 확인했다. COMSOL Multiphysics 유한 요소 수치 해석 모델을 이용하여 자동차용 경음기의 공진 주파수를 예측했고, 음압 실험을 통해 설계된 혼의 작동 주파수를 측정하여 설계 방법을 검증했다. 음압 실험은 홀더를 제외하고 DC 전압을 12 [V] 인가하여 반무향실 환경에서 측정한 결과, 설계 작동 주파수와 비교하여 수 [Hz] 내에서 정확하게 공진이 발생했다. 본 논문에서는 혼의 음향 리액턴스 관점에서 자동차용 트럼펫 혼의 설계 방법을 살펴보았고, 혼을 포함한 시스템을 설계할 때 유용하게 활용될 수 있을 것으로 기대한다.

• 소음진동
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• 제8권4호
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• pp.706-714
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• 1998

The purpose of this study is to analyse the main factors and attributes of psychological evaluation to noise. For this purpose, a psycho-acustic experiment was conducted by using the method of rating scale. 52 subjects were participated in the experiment, 20 stimuli were presented to subjects in random order with 23 adjectives. As a result of factor analysis, it was found that the primary factors for evaluating the quality of noise subjectively are four factors of unpleasantness, intensity, irregularity, and sharpness. And, as a result of MDPREF(multi-dimensional analysis of preference data), it was found that the noise sources including the factors of unpleasantness, intensity, and irregularity are related to the sounds of hammering in construction field, car horn, road traffic, idling of car, and printing by computer printer, and the factor of sharpness are the sounds of car siren, claps of thunder, car horn, and snowstorm etc.

• Design & Manufacturing
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• 제12권3호
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• pp.25-30
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• 2018

Recently The automotive industry is trying to increase the energy efficiency by reducing the weight of the car body and engine components as a way to achieve high energy efficiency. In particular, the reduction of the weight of the vehicle through the weight reduction of the vehicle body has the advantage that the fuel consumption and the output can be improved. But at the same time, there is the disadvantage that the strength becomes weak due to the reduction of the material thickness. Therefore, in order to overcome these disadvantages, materials with high strength according to the unit thickness have been actively developed, and researches for applying them have also been increasing. In this study, we will investigate the application of cold rolled steel sheet, which is a lightweight material, to a horn bracket that secures a installed in an automobile engine room. The horn bracket secures the horn on the car engine and is bolted to the outer wall of the engine. The momentum is acted on the bracket due to the distance between the bolt fastening part and the car horn installed on the bracket end side. Therefore, the body part of the bracket is more likely to be destroyed by the influence of the continuous stress. In this paper, design optimization for weight reduction and strength enhancement was performed to solve this problem, and possibility of applying the rolled steel sheet material as lightweight material by tensile test and fabrication was confirmed.

• 한국화재소방학회논문지
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• 제30권3호
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• pp.94-103
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• 2016

이 논문에서는 1년 전에 구입하여 8,500 km를 주행한 차량에서 발생한 화재사례를 분석하였다. 이 차량은 차량이 적색교통신호로 멈추었다가 파란불로 바뀌어 출발할 때 옆 차량이 경음기를 울려서 차량을 세워 확인해보니 엔진 쪽에 불이 붙어 있었다. 이 차량 화재는 배터리 + 단자에 삽입하여 나사로 조이는 고리의 전기적인 스파크로 인해 발생하였을 가능성이 높은 것으로 분석하였다. 그리고 그 고리의 전기적인 스파크는 제조결함으로 인해 발생한 것이므로 화재발생책임은 소유자나 운전자와 관련이 없이 제조자에게 있는 것으로 분석하였다. 이 차량화재의 화재발생책임과 관련하여 법원에서 제조자의 제조결함을 인정하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.573-574
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• 2009

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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• pp.55-56
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• 2014

• 한국음향학회지
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• 제26권7호
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• pp.323-327
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• 2007

본 논문에서는 객관적으로 정량화된 복합 신호음의 조화도를 새로운 심리 음향 파라미터로 제안하였다. 사람이 복합신호음을 인지하는 과정에서 발생하는 masking 효과, 등청감 곡선, criticalband 등의 심리음향학적인 모델들을 적용시킨 후, 그 소리가 어느정도의 조화도를 갖는지를 정량화시키는 모델을 제안하였고, 이를 검증하기 위하여 복합음으로 구성된 자동차 Horn 신호로 실험을 수행하였다. 실험 결과, 제안한 알고리즘에 의하여 정량화된 객관적인 조화도와 청취 평가를 통한 주관적인 조화도가 0.95의 cross correlation을 보였다. 현재 객관적인 심리음향학적인 파라미터로는 Zwicker 파라미터 외에는 거의 전무한 상태여서 제안하는 알고리즘을 통하여 소리의 심리음향학적인 효과를 보다 객관적으로 파악하는 데에 도움이 될 것으로 보인다.

• 전기학회논문지
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• 제65권7호
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• pp.1263-1269
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• 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.

• Tribology and Lubricants
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• 제30권2호
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• pp.124-129
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• 2014

The piping system accounts for a large portion of the machinery structure of a plant, and is considered as a very important mechanical structure for plant safety. Accordingly, it is used in most energy plants in the nuclear, gas, and heavy chemical industries. In particular, the piping system for a nuclear plant is generally complicated and uses the reactor and its cooling system. The piping equipment is exposed to diverse loads such as weight, temperature, pressure, and seismic load from pipes and fluids, and is used to transfer steam, oil, and gas. In ultrasound infrared thermography, which is an active thermography technology, a 15-100 kHz ultrasound wave is applied to the subject, and the resulting heat from the defective parts is measured using a thermography camera. Because this technique can inspect a large area simultaneously and detect defects such as cracks and delamination in real time, it is used to detect defects in the new and renewable energy, car, and aerospace industries, and recently, in piping defect detection. In this study, ultrasound infrared thermography is used to detect information for the diagnosis of nuclear equipment and structures. Test specimens are prepared with piping materials for nuclear plants, and the optimally designed ultrasound horn and ultrasound vibration system is used to determine damages on nuclear plant piping and detect defects. Additionally, the detected images are used to improve the reliability of the surface and internal defect detection for nuclear piping materials, and their field applicability and reliability is verified.