• 전기전자학회논문지
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• 제23권1호
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• pp.224-229
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• 2019

시트는 운전 중에 운전자와 승차자의 편의를 제공하도록 요구된다. 최근 수동으로 동작하는 시트가 모터를 이용하여 자동으로 동작하는 전동 시트로 변화되고 있다. 시트에 모터를 적용함에 따라 과전류에 의해 발생하는 반전충격음, 진동 및 소음과 같은 문제가 발생하고 있다. 시트 모터의 제어를 통해 문제를 해결하려는 연구가 시도 되고 있다. 본 연구에서는 전동 시트에 사용되는 DC 모터에 흐르는 전류가 소프트 스타트와 소프트 스톱 형태를 갖도록 입력 전압의 형상을 결정하는 4개의 제어변수를 제어하는 기술 제안하였다. 전동 시트의 모델링을 통해 입력 전압에 대한 코일에 흐르는 전류의 관계식을 유도하고, 제어변수에 따른 시뮬레이션을 통해 소프트 스타트와 소프트 스톱 형태를 갖는 최적의 전류 형상의 구현이 가능함을 확인하였다.

• Tribology and Lubricants
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• 제22권3호
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• pp.119-126
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• 2006

In this paper, the contact behavior characteristics of a primary sealing components such as a seal ring and a seal seat has been presented for a small hydro-power turbine. Using the non-linear FEM analysis, the maximum temperature, the axial displacement, radial differences between a seal ring and a seal seat, and maximum contact normal stress have been analyzed for three optimized sealing profiles in which are designed based on the FEM analysis and Taguchi's experimental method. The three primary sealing profiles between a seal ring and a seal seat are strongly related to a leakage of a water for a hydro-power turbine and wear of a primary sealing component. The computed results show that the contact rubbing area between a seal ring and a seal seat is very important for reducing a friction heating and wear in a sealing gap, and increasing a contact normal stress in primary sealing components. Based on the FEM computation, models II and III in which have a small rubbing surface of seal rings show low dilatation of primary sealing components, and high normal contact stress between a seal ring and a seal seat. Thus, the FEM computed results recommend a short contacting width of a primary sealing component for reducing a leakage and thermal distortions, and expanding a seal life. This means that a conventional primary sealing component may be switched to a reduced sealing face of seal rings.

• 동력기계공학회지
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• 제18권6호
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• pp.45-50
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• 2014

In the previous paper, we have reported on the development of foaming sponge seat with the auxiliary spring member and suggested new possibility of the special seat with the auxiliary plastic member for movie theater chair. In this study, we have examined the major design parameters needed in the development of a foaming sponge seat in which the mesh type plastic member are inserted to improve the vibration transfer effect of a chair seat. Through analyzing several prototypes by applying experimentation as well as the experimental modal analysis method, it was confirmed that the effect of vibration transfer can be improved through the use of a mesh type plastic member and applied to the design of practical chair seat.

• 드라이브 ㆍ 컨트롤
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• 제13권4호
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• pp.1-6
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• 2016

Typically, the seat of an automotive vehicle generally includes a horizontal seat-cushion portion and a vertical seat-back portion that is operatively connected to the seat-cushion portion. The seat may include a recliner for the reclining of the seat-back portion relative to the seat-cushion portion by the seat occupant. An energy absorber or damper can also be provided for the seat-back portion. Because the recliner is configured to be released at a relatively high speed, and it results in an impact at the end of a folding stroke, the damper needs to dissipate energy as the seat back moves with respect to the seat cushion; therefore, the role of the seat damper in the automotive-seat design is important. In this paper, the mechanism of an hydraulic-type automotive-seat damper is investigated, and the torque characteristic is simulated according to the design-parameter variations such as the orifice area and the working-fluid properties.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.210-214
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• 2007

A simulation program has been developed to evaluate operator seat vibration for earth-moving machinery and decide whether a seat meets the requirements imposed by ISO 7096. An operator seat is assumed as a linear system composed of a mass, a spring, and a damper mounted on a platform. The program evaluates the transmissibility at resonance, and the SEAT factors for a light person and a heavy person. The developed program can be utilized effectively in designing a new operator seat.

• 동력기계공학회지
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• 제3권3호
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• pp.91-96
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• 1999

This study is about the design and analysis ot a suspension damper for truck driver's seat to improve the ride comfort. Trucks are usually subjected to hostile driving environments. Therefore, many truck driver's seat have suspension seats to isolate the vibration from the cab floor panel. Because the vehicle suspension system can reduce the primary vibration from the ground, only low frequency vibration can be transmitted to the driver's seat. But, this low frequency vibration can be harmful to the driver. The seat damper is very critical element to improve the ride comfort for the driver. In this study, a four-stage damper is designed and analyzed for the vibration capability. The damping coefficient of this damper can lie manually controlled in response to the road and driving environment.

• 한국자동차공학회논문집
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• 제17권3호
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• pp.35-44
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• 2009

The purpose of this paper is to describe experimental results about the T-joint welding of the high power continuous wave (CW) fiber laser for SAPH steel plate for seat frame of car. The seat rail is a part of seat frame of cars. The assembling method is mostly fix up using a bolt and nut. But this assembling method has many demerits in productivity such as increasing work process and material cost. This paper presents an experimental study about Laser T-Joint weldability of seat rail. Laser welding has many advantages in lightness and saving material costs of seat frame. The laser beam was moved along the work pieces by six axis robot with process optical fiber. The laser beam is focused with a welding head within incident angle $15{\sim}45^{\circ}$ for the purpose of the T-joint welding through two side full penetration. The range of the root gap size is less than ${\leq}0.4mm$. Optical microscopy SEM were performed to observe the micro structures and determine the structures of welded zone.

• 동력기계공학회지
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• 제17권6호
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• pp.40-46
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• 2013

This paper describes the suggestion of the special seat with the auxiliary plastic member for movie theater chair. In the previous paper, we have reported on the development of foaming sponge seat with the auxiliary spring member. And we have confirmed that it was more effective on vibration transfer than the chair seat of foaming sponge only. In this study, we have examined the major design parameters needed in the development of a foaming sponge seat in which the mesh type plastic member are inserted to improve the vibration transfer effect of a chair seat. By applying experimentation to the prototype as well as the experimental modal analysis method, we made sure that the effect of the vibration transfer could be improved through the use of a mesh type plastic member as similar as the auxiliary spring member.

• Industrial Engineering and Management Systems
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• 제10권3호
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• pp.185-190
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• 2011

A driver interacts directly with the car seat at all times. There are ergonomic characteristics that have to be followed to produce comfortable seats. However, most of previous researches focused on either static or dynamic condition only. In addition, research on car seat development is critically lacking although Malaysia herself manufactures its own car. Hence, this paper integrates objective measurements and subjective evaluation to predict seat discomfort. The objective measurements consider both static and dynamic conditions. Steven's psychophysics power law has been used in which after expansion; ${\psi}\;=\;a+b{\varphi}_s^{\alpha}+c{\varphi}_v^{\beta}$ where ${\psi}$ is discomfort sensation, ${\varphi}_s^{\alpha}$ is static modality with exponent ${\alpha}$ and ${\varphi}_v^{\beta}$ is dynamic modality with exponent ${\beta}$. The subjects in this study were local and the cars used were Malaysian made compact car. Static objective measurement was the seat pressure distribution measurement. The experiment was carried out on the driver's seat in a real car with the engine turned off. Meanwhile, the dynamic objective measurement was carried out in a moving car on real roads. During pressure distribution and vibration transmissibility experiments, subjects were requested to evaluate their discomfort levels using vehicle seat discomfort survey questionnaire together with body map diagram. From subjective evaluations, seat pressure and vibration dose values exponent for static modality ${\alpha}$ = 1.51 and exponent for dynamic modality ${\beta}$ = 1.24 were produced. The curves produced from the $E_{q.s}$ showed better $R_{-sq}$ values (99%) when both static and dynamic modalities were considered together as compared to Eq. with single modality only (static or dynamic only R-Sq = 95%). In conclusion, car seat discomfort prediction gives better result when seat development considered both static and dynamic modalities; and using ergonomic approach.

• 한국기계가공학회지
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• 제18권2호
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• pp.29-37
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• 2019

In this study, emotional adjectives about the operating sound quality of the vehicle power seat are constructed, and the effectiveness of the emotional adjectives are verified by evaluating the operating sound quality. First, emotional adjectives were collected from the literature related to the automobile field and other sound qualities. A questionnaire was made using these adjectives. The questionnaire was designed to be able to select all adjectives that could express the operating noise of the power seat slide adjuster by applying the multiple- response method. Next, a subjective sound quality evaluation was conducted using the emotional adjectives. In the evaluation, we first recorded the operating noise for two power seats. Second, the subjective sound quality evaluation was performed on the recorded operating noise using a loudspeaker. Finally, through a statistical analysis on the sound quality evaluation results, the relationship between the semantic space and the preference score was verified, and the validity of the emotional adjectives was verified.