• 한국철도학회논문집
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• 제3권3호
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• pp.131-138
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• 2000

The design of current collection system of high speed train requires the fundamental understandings for the dynamic characteristics of catenary system and pantograph. The stiffness of catenary system of high speed train has the varying characteristics for the change of contact point with pantograph, since the supporting pole and hanger make the different boundary conditions for the up-down stiffness of a trolley wire. The variation of stiffness results in Mathiue equation, which characterizes the stability of the system. However, the two-term variation of the stiffness due to span length and hanger distance cannot be solved analytically. In this paper, the stiffness variations are calculated and the physical reasoning of linear model and one term Mathieu equation are reviewed. And the numerical analysis for the two-term variation of the stiffness is done for the several design parameters of pantograph.

• 한국가구학회지
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• 제24권4호
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• pp.318-328
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• 2013

This study aimed to examine the theoretical consideration and concept of hybrid that could be applicable to wood product design, to analyze design trend according to the morphological transformation by means of combination of hybrid material and function, to understand the correlation between type of wood product and materials and to apply it to the domestic and overseas hybrid concept of wood product design study. A study of assembling output by empirical experiment to embed natural resources into acrylic resin in order to develop wood products was carried out. And an wood product was suggested that satisfied lighting and hanger function through a new wood product design development combined with hanger function and lighting function. Through such process, a new design paradigm was suggested to cope with the periodic trend and to induce mass production of designed product. Thus, this study set a new guideline for activating wood product design and attempted to meet the social demand of encouraging new value creation.

• 한국자동차공학회논문집
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• 제12권4호
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• pp.42-49
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• 2004

When a truck cab is conveyed at a constant speed by a hanger and immersed into the painting reservoir, it may fall off from the hanger by buoyancy. In order to reduce the buoyancy, on the bottom of a cab panel are holes placed, which allow paint to flow into the inside of a cab. In this study, a differential equation is derived which can be solved numerically by using 4th-Order Runge-Kutta method to calculate transient behavior of the buoyant force with sizes and locations of the holes given. The solution is utilized to optimally determine sizes and locations of the holes.

• 오토저널
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• 제12권4호
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• pp.47-55
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• 1990

This study is the first step for the grasp of transfer path to the vibration generated from the automotive engine and consideration of counterplan for optimal design and low vibration, low noise of the exhaust system. In this study, by applying the theory of modal analysis and experiment, vibrational reduction effect is evaluated according to the attachment of flexible coupling to the exhaust system. And data for the design is suggested to improve the characteristics of vibration. The vibration isolation and damping characteristics are improved due to the attachment of flexible coupling to the exhaust system. As a result, it is identified that flexible coupling which has good flexibility is more effective for the improvement of vibrational characteristics. By the estimation of modeshape of vibration, the location of optimal damping hanger is determined in the viewpoint of vibration isolation. Also it is confirmed that the characteristics of vibration is improved due to the attachment of damping hanger.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.134-139
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• 2001

Pantographes should follow periodical motions with hanger and span passing frequencies during operation in order to have good dynamic follow-up characteristics. According to the dynamic simulations of a pantograph together with catenary systems, the best current collection performance of a pantograph is obtained when receptance peak frequencies are matched with hanger and span passing frequencies. Based on this principle, design variables of G7 pantograph are selected. However, because a high-speed train may run in the wide range of speeds and induce aero-acoustic noises, the design variables are adjusted to escape from these problems with a little sacrifice of current collection performance.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.598-605
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• 2000

The design of a current collection system of high speed train requires the fundamental understandings fer the dynamic characteristics of a catenary system and pantograph. The stiffness of the catenary system of high speed train has the varying characteristics for the change of the contact point with a pantograph, since the supporting pole and hanger make the different boundary conditions for the updown stiffness of a trolley wire. The variation of stiffness results in Mathiue equation, which characterizes the stability of the system. However, the two terms variation of the stiffness due to span length and hanger distance cannot be solved analytically. In this paper, the stiffness variations are calculated, and the physical reasoning of linear model and one term Mathieu equation are reviewed. And the numerical analysis for the two term variation of the stiffness is done for the several design parameters of the pantograph.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.730-735
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• 2005

In this thesis, As electric railway vehicle's speed becomes faster and faster and functional, the conditions of operation (or running condition) of the vehicle also become complicated and diverse. As the number of electric vehicle increases by enhancement of the running condition, problems are also raised in circulation current, vibration and unstable contact caused by equipment(sporting part for making horizontal between Trolley wire and Messenger wire) and troubles in Ark by un secure contact. This articles shows a method to prevent or to have least problem of vibration, and unstable contact by having constant height of Trolley wire through adjusting the length of Hanger.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.550-557
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• 1999

Results of the dynamic simulation on KTX catenary and catenary-pantograph interface are presented. Simulation programs based on finite element and finite difference models of the catenary are developed, while the pantograph is modeled as a linear 3-degree-of-freedom system. The catenary motion dynamics are primarily determined by the transmission and reflection of the propagating disturbance wave at the hanger and span boundaries. On the other hand, the catenary-pantograph contact characteristics are primarily influenced by the movement of the pantograph across the hanger and span boundaries, the amount of damping present in the contact wire, and the resonant frequencies of the pantograph.

• Elastomers and Composites
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• 제55권4호
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• pp.329-338
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• 2020

In this study, three different die geometries were selected to understand the die characteristics in the film casting extrusion processes. First, large and small-scale T-dies were numerically simulated to observe the scaled-down effect on the flow inside the dies. Second, three different dies-keyhole, linear tapper coat-hanger die (LTCD), and curved tapper coat-hanger die (CTCD)-were numerically observed and discussed according to the mass flow rate. Finally, the die exit velocity profiles and die characteristics were observed and discussed based on the power-law index for the LTCD die. These numerical simulations and numerical data will aid the optimization of the die design in industrial fields.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 추계학술대회
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• pp.811-814
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• 2011

본 논문에서는 무선 Radio Frequency Identification (RFID) 리더기 단말을 이용한 대량의 세탁물 및 의류의 효율적인 관리를 위한 스마트 세탁물 관리 시스템을 제안한다. 제안하는 시스템은 크게 무선 RFID 옷걸이, 베이스 모듈, 서버 시스템으로 구성되어지며, RFID 리더기가 부착된 무선 RFID 옷걸이는 세탁물에 부착된 RFID 태그를 읽어 무선으로 서버에 전송한다. 서버와 연결된 베이스 모듈은 무선 RFID 옷걸이와 통신을 하고 서버에 정보를 전송한다. 서버 시스템에서는 DB를 통해 의류를 관리하고 웹페이지 및 스마트폰을 통해 정보를 게시할 수 있다. 제안한 시스템의 무선 센서 노드는 배터리로 동작되기 때문에 전류 소모량을 측정하여 수명을 예측할 수 있다. 본 시스템은 세탁소 이외에도 대량의 의류관리에도 사용되어 질수 있으며, 또한 세탁 과정에서의 효율성을 증대 시킬 수 있는 서비스가 될 것이다.