• Journal of the Korean Society for Railway
• /
• v.18 no.2
• /
• pp.139-148
• /
• 2015

By increasing the vertical stiffness of the rail fastening system, the dynamic wheel load of the vehicle can be increased on the ballast track, though this increases the cost of track maintenance. On the other hand, the resistance acting on the wheel is decreased, which lowers the cost of the electric power to run the train. For this reason, the determination of the optimal fastener stiffness is important when attempting to minimize the economic costs associated with both track maintenance and energy to operate the train. In this study, a numerical method for evaluating the optimal vertical stiffness of the fasteners used on ballast track is presented on the basis of the process proposed by L$\acute{o}$pez-Pita et al. They used an approximation formula while calculating the dynamic wheel load. The evaluated fastener stiffness is mainly affected by the calculated dynamic wheel load. In this study, the dynamic wheel load is more precisely evaluated with an advanced vehicle-track interaction model. An appropriate range of the stiffness of the fastener applicable to the design of ballast track along domestic high-speed lines is proposed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.04a
• /
• pp.366-370
• /
• 2014

Considering a countermeasure against vibration along the existing line, in many cases, it may be the most efficient method to replace existing fasteners with high resilient fasteners because of the restriction of the construction of a new track type. There are many types of high resilient fasteners which are different in price and performance. Therefore it is important to choose the high resilient fastener which has best vibration-proof performance per price. In this study, a prediction method which can exactly evaluate the performance of a fastener in the reduction the ground borne noise in the existing line is presented, which is constructed based on the combination of the measurement and the simulation. A numerical example using the presented method is introduced to evaluate the vibration-proof performance for the solution of the vibration problem in the existing line.

• Proceedings of the Safety Management and Science Conference
• /
• 2008.04a
• /
• pp.417-428
• /
• 2008

Designers have to consider voice of customer, process capability, manufacturing standards & condition, manufacturing method, characteristics of products to decide tolerances. Especially, in case of position of hole and pin, designers have to consider process capability to decide tolerances. The traditional position tolerances used in a drawing are theoretical values which are allocated to position under the worst case assembling condition that both hole and pin are the maximum material condition(MMC). However, When the process capability is high, more exact product size can be produced under stable manufacturing condition. larger clearance of hole and pin can be allocated. In this point of view, manufacturer could increase the yield by allocating larger position tolerance than theoretical position tolerance of hole and pin considering process capability.

• Journal of the Korea Safety Management & Science
• /
• v.11 no.1
• /
• pp.75-85
• /
• 2009

Designers have to consider voice of customer, process capability, manufacturing standards & condition, manufacturing method and characteristics of products to decide tolerances. Especially, in case of position of hole and pin, designers have to consider process capability to decide tolerances. The traditional position tolerances used in a drawing are theoretical values which are allocated to position under the worst case assembling condition that both hole and pin are the maximum material condition(MMC). However, when the process capability is high, more exact product size can be produced under stable manufacturing condition. Larger clearance of hole and pin can be allocated. In this point of view, manufacturer could increase the yield by allocating larger position tolerance than theoretical position tolerance of hole and pin considering process capability.

• Proceedings of the KAIS Fall Conference
• /
• 2011.12b
• /
• pp.639-642
• /
• 2011

본 논문은 LED 등기구 브라켓의 제품 생산방법의 개선에 관한 연구이다. 기존의 제품 생산시 레이저컷팅 ${\rightarrow}$ 절곡 ${\rightarrow}$ 도금 ${\rightarrow}$ 체결핀 가공 ${\rightarrow}$ 스프링 도금 ${\rightarrow}$ 조립 순으로 제작되어 LED 조명 등기구를 제작하였으나, LED 조명 등기구의 대량 생산이 요구되어 기존의 방법으로는 원가가 상승되어 고객이 원하는 가격에 생산할 수 있는 방법이 없어서 전용 금형을 제작하여 생산성 향상과 품질향상, 원가절감을 이루고자 하였다. 이에 본 논문에서는 LED 등기구 브라켓을 생산하기 위한 전용금형을 제작하여 생산시 개선전과 개선후의 결과에 대하여 연구하였다.

• Journal of the Korean Society for Railway
• /
• v.16 no.3
• /
• pp.207-216
• /
• 2013

The components of concrete track (rail and rail fastening system) in railway bridge deck ends are damaged and deteriorated by track-bridge interaction forces such as uplift forces and compression forces owing to their structural flexural characteristics (bridge end rotation). This had led to demand for alternatives to improve structural safety and serviceability. In this study, the authors aim to develop a transition track to enhance the long term workability and durability of concrete track components in railway bridge deck ends and thereby improve the performance of concrete track. A time-history analysis and a three-dimensional finite element method analysis were performed to consider the train speed and the effect of multiple train loads and the results were compared with the performance requirements and German standard for transition track. Furthermore, two specimens, a normal concrete track and a transition track, were fabricated to evaluate the effects of application of the developed transition track, and static tests were conducted. From the results, the track-bridge interaction force acting on the track components (rail displacement, rail stress, and clip stress) of the railway bridge deck end were significantly reduced with use of the developed transition track compared with the non-transition track specimen.

• The Optical Journal
• /
• s.99
• /
• pp.36-38
• /
• 2005

2000년 4월 경기도 안양시 동안구 호계동 안양국제유통단지내에 둥지를 튼 존테크(대표·최상규)는 광 관련 전자, 기계 조립 및 검사장비 전문업체이다. 디스플레이 생산에 필요한 각종 기자재 및 장비 공급을 통한 기반구축을 시작으로 2003년부터는 디지털카메라 및 카메라폰과 관련한 제조 및 시험장비를 30년 전통을 가진 일본 카메라 및 LCD 장비 전문회사와 공급계약을 체결하고 본격적인 국내 판매를 시작했다. 현재는 광학장비 유통에 집중하고 있으나 향후에는 회사 설립 전부터 쌓아온 풍부한 경험과 지식을 바탕으로 광학검사장비 개발 및 제조에 모든 역량을 집중하여 관련 장비의 국산화를 이루겠다는 큰 포부를 가지고 있다.

• 발명특허
• /
• v.10 no.5 s.111
• /
• pp.71-71
• /
• 1985

반도체, 컴퓨터, 통신기기 분야에서 최첨단 기술제품의 생산 공급을 통해 그동안 국내 전자산업을 선도해 온 금성반도체(대표 : 구자두)는, 지난해 6월 세계 3번째로 반주문형 초대규모 집적회로(VLSI)인 CMOS게이트 어레이를 개발하여 미국 엘에스아이 로직(LISLOGIC)사와 1억 5천만불의 수출계약을 체결함으로써 국내 최초로 주문형 반도체의 수출시대를 연데이어, 4월 10일 여의도 중심부 신한 빌딩 4층에 100여평 규모의 게이트 어레이 디자인 센터를 개관하여 특수한 반도체를 주문하는 고객이 동 제품의 회로 설계과정에 직접참여할 수 있도록 함으로써 수주활동을 본격화 하는 일대 전기를 마련하였다.

• The tire
• /
• s.235
• /
• pp.10-17
• /
• 2008

한중일 3국간 경제협력이 강화되고 있다. 우리나라는 그 동안 칠레, 아세안, EFTA, 미국과 EU 등 원거리에 있는 국가와 자유무역협정(FTA) 체결을 위한 협상을 벌여 왔다. 이 과정에도 아직도 FTA에 대한 찬반 논란이 끊이지 않고 있지만 04년 이후 중단되었던 한일 FTA협상을 재개할 것인가에 대한 검토가 이루어지고 있다. 또한 한중 FTA의 타당성과 추진 시기에 대해서도 검토되어야 한다는 견해가 대두되고 있다. 한중일간의 FTA 협상이 본격화될 경우 우리나라는 본격적인 시장개방과 함께 동북아협력의 새로운 시대를 맞이할 전망이다. 본 고에서는 최근 한중일 자동차산업의 동향 및 협력현황을 살펴 보고 동북아 3국간 새로운 협력시대의 전개와 그 시사점을 도출해 보기로 한다.

• International Commerce and Information Review
• /
• v.17 no.3
• /
• pp.177-201
• /
• 2015

Korea-China FTA was initialized in 2015. Korea has a high level of dependence on trade for its economic growth, especially to China. Technical Barriers to Trade(TBT) among various non-tariff barriers is becoming increasingly important. Elimination of TBT is one of the key issues in which the South Korean government is interested since technical barriers significantly affect trade between the two countries. MRA has been considered as an effective tool to relieve such technical barriers. Several studies and surveys showed that MRA would mitigate the barriers of import and solve the problems that many companies face in international market. This study tries to seek utilization plan of MRA for Korea-China FTA. It suggests suitable utilization plan of MRA considering the difference of technical regulations between two countries. This paper has value in that it provides specific MRA strategies targeting China while other prior studies have merely analyzed the necessity of MRA.