• 월간포장계
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• 통권282호
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• pp.93-101
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• 2016

딸기 포장재용으로 새로이 개발된 공중부양형 구조의 용기를 가지고 딸기가 유통 중 발생할 수 있는 짓물림 방지효과가 있는지를 분석하기 위해 일본 후쿠오카 현 쯔꾸시 시에서 도쿄까지 트럭과 항공기에 의한 수송시험을 했다. 일반적으로 사용되는 EPS용기는 수송 중 딸기 간 포장면적이 많아 흠집 발생면적이 컸으며, PET 트레이 위에 딸기를 배열시키는 '보통들이형 용기'는 과일끼리의 접촉부분에서 짓물림 현상이 많이 발생했다. 개발된 '공중부양형 용기'는 과일끼리의 접촉 없이, 유연한 PE필름으로 포장돼 수송 중 발생하는 딸기의 흠집 발생이 가장 적었다. 또한 'EPS 용기' 및 'PET용기'에 25Hz의 정상 진동을 가한 결과, 용기 내부에 발생하는 진동의 주파수 종류에 차이가 있음을 확인할 수 있었다. 'EPS용기'에서는 가진동의 25Hz보다도 큰 주파수의 진동을 많이 확인할 수 있었다

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.347-350
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• 2011

Automobiles should be light and practical to reduce the price of manufacturing and maintaining expense. Hatchback vehicles are far from the silence for its practicality. This paper introduced the effective method of the planning of the asphalt material which applies the asphalt damping material. This paper showed the experiment which restrains the vibration of the vehicle trunk using asphalt damping material and chose the position of damping material using the velocity map and strain energy map and planed the optimum position.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.602-606
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• 2011

In this study, operational vibration experiment and analysis have been conducted for the 4-blade small vertical-axis wind turbine (VAWT) including the effect of tower elastic behavior. Computational structural dynamics analysis method is applied to obtain Campbell diagram for the VAWT with elastic tower. An open type wind-tunnel is used to change and keep the wind velocity during the ground test. Equivalent reduced elastic tower is supported to the VAWT so that the elastic stiffness effect of the tower can be reflected to the present vibration experiment. Various excitation sources with aerodynamic forces are considered and the dominant operating vibration phenomena are physically investigated in detail.

• 한국소음진동공학회논문집
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• 제14권10호
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• pp.983-989
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• 2004

In this paper, a modeling method for the vibration analysis of rotating structures employing multi-reference frames is presented. The geometric stiffening effect that results from centrifugal inertia force is considered. In most previous studies single reference frame has been employed for the analysis. In the present study, a modeling method employing multi-reference frames is presented, and the effects of employing multi-reference frames on the analysis accuracy are investigated through solving numerical examples.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.924-928
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• 2002

Response of the rail surface is an important factor for the train safety and comfortable travel, and evaluation of vibration at the area along a rail is an important factor for the vibration. The dominant method to reduce the vibration that reach the ground is installing vibration absorber between rall and the under structure. In this paper, we evaluated the vibration reducing effect of using vibration control sleeper pads to slave and earth at certain distance from the sleepers.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.121-126
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• 2002

In a recent construction industry, cable supported structures such as a cable-stayed bridge or space stadium have been increasingly constructed. Generally the stay cables as a critical member should be adjusted to be satisfied with the design tension forces. In this purpose, a vibration method has been applied to estimate the tension forces exerted to the existing stay cables. In this study, cable vibration tests were carried out to estimate the cable tension forces comparing with theoretical and practical formulas. From the measured frequencies obtained from free vibration and impulsive tests, the accuracy of 1he estimated tension forces is confirmed according to use only the first single mode or higher multiple modes.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.978-983
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• 2014

This research proposes a method to estimate the fatigue life of solid-state drive(SSD) due to the effect of dummy solder ball under forced vibration. Mechanical jig is developed to describe the SSD in laptop computer. The jig with SSD is mounted on a shaker, and excited by a sinusoidal sweep vibration within the narrow frequency band around the first resonant frequency until the SSD fails. A finite element model of SSD is also developed to simulate the forced vibration. It shows that the solder joints at the corners of controller package are most vulnerable components and that placing dummy solder balls at those area is effective method to increase fatigue life of SSD.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.902-909
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• 2006

In this study, three-dimensional rotordynamic analyses have been conducted using equivalent beam, hybrid and fun three-dimensional models. The Present computational method is based on the general finite element method with rotating gyroscopic effects of a rotor system. General purpose commercial finite element code, SAMCEF which includes practical rotordynamics module with various types of rotor analysis methods and bearing elements is applied. For the purpose of numerical verification, comparison study for a benchmark rotor model with support bearings is performed first. Detailed finite element models based on three different modeling concepts are constructed and then computational analyses are conducted for the realistic and complex three-dimensional rotor system. The results for rotor stability and mass unbalance response are presented and compared with the experimental vibration test conducted in this study.

• 소음진동
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• 제10권5호
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• pp.830-837
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• 2000

This paper deals with an analysis and countermeasure of escalator vibration. The vibration characteristics of escalators are studied theoretically and experimentally to fine the main cause of severe vibration. The main source of vibration in escalators is found to be chordal effect due to the step chain and sprocket system. It is also found that the vibration become significantly large at so called no load condition, in which the load due to passengers, during down-moving, is equal to the resistive force in the driving system. Dynamic absorbers are implemented to suppress the vibration, A theoretical analysis is made to determine the appropriate dynamic absorber. Theoretical and experimental study shows that dynamic absorber is effective to suppress the vibration in escalators.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2010년도 정기 학술대회
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• pp.725-728
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• 2010

풍력실험결과를 이용한 풍하중 산정 방법은 고층건물에 작용하는 풍하중을 산정하는 대표적인 방법이다. 일반적인 고층건물의 경우, 이 방법은 구조물의 형상에 변화가 없다면, 구조물의 고유진동수가 증가할수록 구조물에 작용하는 풍하중 크기는 감소하는 특성을 가지고 있다. 한편, 재분배기법은 단위하중법을 통해 계산되는 변위기여도를 근거로 하여 구조물의 형상은 유지하면서 각 부재 단면의 크기만을 변화시켜서 구조물의 강성을 조절하는 설계기법이다. 이 방법은 효과적인 물량 재분배를 통해 구조물의 강성을 증가시키고 이를 통해 구조물의 고유진동수를 증가시키는 특징을 가진다. 본 논문에서는 재분배기법을 이용하여 고층건물 구조설계 시 구조물에 작용하는 풍하중 크기를 합리적으로 감소시키는 방법을 제안하였다. 제안된 방법을 풍력실험을 실시한 실구조물에 적용한 결과 구조물에 작용하는 풍하중 크기가 감소하고, 이를 통해 구조물량을 효과적으로 감소시킬 수 있음을 확인하였다.