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Passengers sitting on the back seats of cars while talking on their mobiles can easily experience the invasion of their speech privacy by the driver. Protecting speech privacy can be done by utilizing masking sounds - masking sound may be so loud that it annoys both drivers and speakers. In this research, the feasibility of utilizing active noise control (ANC) which aims to reduce the level of speech at the driver’s seat and, hence, is able to lower the needed level of masking sounds while still protecting the speech privacy is investigated. Speech reception threshold (SRT), which is a subjective measurement method for speech intelligibility, is proceeded for seeing the effect of ANC on speech intelligibility when the masking sound is in use. The SRT measurement result implied that utilizing ANC to reduce the speech level of the back-seat passenger at the driver’s seat is able to lower the needed level of masking sound for keeping the speech privacy.

Automotive companies are trying to enhance the customer’s impression by improving engine sound quality. The target of this sound quality is to create a brand sound that is preferred by their customers as well as quietness of interior noise. Over the past decade there have been many studies in the field of automotive sound quality. These have included the technologies such as tuning of intake orifice and exhaust orifice, tuning of structure-borne, intake feedback devices, active exhaust valves, ANC (Active Noise Cancellation) and ASD (Active Sound Design). The three elements of the sound that affect the feeling of the customer are known as engine order arrangement, frequency balance, and linearity. Here, the most important thing in sound quality development is the order arrangement.

Over the past decade, there have been many efforts to generate engine sound inside the cabin either in reducing way or in enhancing way. To reduce the engine noise, the passive way, such as sound absorption or sound insulation, was widely used but it has a limitation on its reduction performance. In recent days, with the development of signal processing technology, ANC (Active Noise Control) is been used to reduce the engine noise inside the cabin. On the other hand, technologies such as ASD (Active Sound Design) and ESG (Engine Sound Generator) have been used to generate the engine sound inside the vehicle. In the last ISNVH, Hyundai Motor Company newly introduced ESEV (Engine Sound by Engine Vibration) technology. This paper describes the ESEV Plus Minus that uses engine vibration to not only enhance the certain engine order components but reduce the other components at the same time. Consequently, this technology would produce a much more diverse engine sound.

This paper addresses the indoor passby noise measurement techniques satisfying SAE J1470 Recommended Practice. The restrictions of the suggested methods are also investigated. We suggested the passby noise measurement method in a large semi-anechoic chamber. We also have tried two prediction methods using array microphone system to predict the passby noise in a small-size semi-anechoic chamber. The first method is based on the line array microphone method. This method is found to be only applicable in the nearfield, because spherical Hankel function is used as a basis function. This is just simple consequence of fact that the basis functions are not separable in the farfield. The second one is the well-known nearfield acoustic holography(NAH). Not only the detailed procedures of applying NAH to the passby noise prediction but also the drawback of this method are discussed.

It is a global research and development trend to introduce electric vehicle into the market in a prompt manner; however, there have been technological issues with batteries, or in general, an energy storage technology in moving vehicles. KAIST, a globally leading university majoring in science and technology in Korea, has been developing a break-through wireless power transfer technology by applying inductive power transfer technology, as demonstrated in a public park in March, 2010, which is referred to as “OLEV- On-line Electric Vehicle.” With the technology, it is possible to drive the electric powertrain and charge its battery simultaneously while the vehicle is in operation on the road. In this paper, a couple of specific noise and vibration phenomena are introduced which have been observed during the development phase of the proto-type of test vehicle.

An accurate vehicle structural vibration analysis, in medium or high frequency range, is necessary for structural redesign to reduce the vehicle interior noise, however, FE analyses in those frequency ranges are usually inaccurate. To overcome this difficulty, a guide for using experimental data instead of finite analysis results was studied. Formulations for the sensitivity of FRFs and harmonic responses are derived, and a structure-acoustic coupling analysis in modal domain was done to cure the structure-bone noise problem. Also, a technique for determining the proper modification positions or regions for reducing the interior noise level is suggested and tested both numerically and experimentally with a 1/2 scale vehicle model.