• 한국철도학회논문집
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• 제14권4호
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• pp.370-375
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• 2011

본 논문은 <이진선-김경태[2]>의 후속연구로서 대중교통시스템 차원에서 PRT의 실제 적용시의 편익 등을 검토하여 경제성을 검토하고자 하였다. 기존 연구에서 산정된 수요를 바탕으로 실제 운영시 필요한 PRT 소요차량수와 편익을 검토하였다. 대상지역은 난곡지구로 선정하여 적용성을 검토하였으며, 기종점별로 소요차량 수를 산정한 결과, 요금수준이 800원일 때, 합승을 허용하지 않을 경우 160대가 필요하고, 최대 175대가 필요한 것으로 분석되었다. 또한 PRT 수송수요와 역간 통행시간을 근거로 한 편익 산정 결과를 보면 요금수준이 800원일 때 2011년 6,444백만원, 2016년 6,408백만원, 2021년 6,354백만원으로 나타났다. 도출된 편익을 기준으로 하여 분석기간을 30년으로 할 경우 운임수준 800원, ${\alpha}$값이 1.0일 때의 2005년 기준 편익의 현재가치는 47,185백만 원인 것으로 분석되었으며, PRT 시스템의 구축비가 km당 80억원 수준일 때 운영비는 연간 시스템 구축비의 약 4.63% 수준이 되어야 경제적 타당성을 확보할 수 있는 것으로 분석되었다. 결과적으로 PRT 사업의 경제적 타당성은 시스템 구축비를 얼마만큼 줄일 수 있느냐에 따라 결정된다고 할 수 있다. 따라서 PRT 기술개발사업은 최대한 경량화를 목표로 하여 인프라 구축과 차량비에 소요되는 비용을 최대한 줄일 수 있는 방향으로 연구가 진행되어야 할 것으로 본다.

• 한국인터넷방송통신학회논문지
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• 제21권2호
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• pp.7-14
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• 2021

사물인터넷과 자유주행 차량의 급속한 기술 발전과 함께, 그 시스템의 복잡성의 수준도 증가하고 있다. 따라서 관련 기업들은 기존의 부피가 큰 단일 서비스 아키텍처를 마이크로서비스 기반 아키텍처로 변경함으로써 증가하는 복잡성을 관리해오고 있다. 그러나 이러한 마이크로서비스의 활용과 배포를 위한 기본 통신 메커니즘은 간헐적이고 연결상태의 문제와 함께 짧은 지연 시간 요건 때문에 미래형 자율주행차량의 요건을 충족하기 어려웠다. 본 논문에서는 정보 중심 네트워킹(ICN) 패러다임을 기본 통신 아키텍처로 채택하여 기존의 문제점들을 해결할 것을 제안한다. 본 연구에서는 자율 차량 시스템을 구축하기 위한 마이크로서비스 접근방식이 ICN을 활용하여 좀 더 효과적인 서비스 제공 및 효율적인 서비스 분배와 균일한 서비스 발견을 달성할 수 있다는 부분에 대하여 조사, 분석 하였다. 본 논문에서 제시하는 방향성은 정보 중심의 마이크로서비스 접근 방식의 비전이 더 효과적이고 가벼운 자율 차량 서비스와 통신 프로토콜 연구에 초점을 맞추는 데 도움이 될 것이다.

• International Journal of Automotive Technology
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• 제7권5호
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• pp.565-570
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• 2006

The development of a light-weight vehicle is in great demand for enhancement of fule efficiency and dynamic performance. The vehicle weight can be reduced effectively by using lightweight materials such as aluminum and magnesium. However, if such materials are used in vehicles, there are often instances when different materials such as aluminum and steel need to be joined to each other. The conventional joining method, namely resistance spot welding, cannot be used in joining different materials. Self-piercing rivet(SPR) and adhesive bonding, however, are good alternatives to resistance spot welding. This paper is concerned with the crushing test of double hat-shaped member made by resistance spot welding, SPR and adhesive bonding. Various parameters of crashworthiness are analyzed and evaluated. Based on these results, the applicability of SPR and adhesive bonding are proposed as an alternative to resistance spot welding.

• 한국정밀공학회지
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• 제30권8호
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• pp.797-801
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• 2013

Today's automotive industry is evolving toward low-emissions or zero-emissions high-efficiency vehicles. Highly efficient power sources are required, as well as high strength steels for various parts to increase safety. In this study, we investigated the roll-forming process for the development of high strength, lightweight steel bumper beams. The roll-forming process was analyzed using the software package Shape-RF in combination with a rigid-plastic finite element method model. An optimal roll-forming process based on roll-pass was obtained using finite element method simulations.

• 한국기계가공학회지
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• 제8권4호
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• pp.136-142
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• 2009

The vehicle's light-weight technology is divided into optimization of structure geometric and material. Structure geometric optimization and improvement of materials has examined to be power-train and maintenance on the severe condition. The core technology of Special vehicle's light-weight is constitute by Drop box, Axle and Final reduction gear. Technology and product of the parts is high to overseas and import dependency. We will want to examine the possibility of light-weight for the Axle Case and Drop box-connections. In this research, conventional design of excess weight will inhibit the mobility and fuel efficiency. Through the improvement of Axle material, we saw the possibility reducing weight. If you use the results of these studies, it will be available to domestic production technology and reducing weight of RV car, Dump truck, Track crain, etc.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.401-407
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• 1998

Recently, as the railway vehicles become speedy and massive, the collision is being regarded as an important factor for the assessment of safety for passenger. And the study of collision is being in progress more actively in advanced nations. In this study, the collision analysis is performed by using non-linear dynamic finite element program PAM-CRASH. The carbody used in analysis is made of Aluminum AL6005A to realize lightweight, and designed and manufactured by DHI (Daewoo Heavy Industry) lately. For the accuracy of the result in the practical collision, the experiment of material properties has been performed. The result of the analysis shows the underframe of rolling stock is the most important part as a collision energy absorbing structure. Further study is needed for optimal design which enables the carbody shell structure to disperse absorbing energy adequately.

• 한국생산제조학회지
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• 제21권1호
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• pp.90-94
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• 2012

This study evaluates the strength of surface treatment parts using the hard anodizing method to the aluminum alloy brake disks. In order to achieve weight reduction of vehicles, Eco-friendly cars parts of the high-quality and competitive price is to equip. Especially while pursuing parts of weight reduction, it has to maintain the strength of the surface of the brake by nature. To enhance surface strength of aluminum alloy, we use hard anodizing technology in the surface treatment. This study is resulted of 3 times greater the hardness value of the hard anodized specimen than the aluminum alloy specimen for the lightweight parts of EV brake disk

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.338-343
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• 2005

We have evaluated the structural integrity of a sandwich composite train roof which can find a lightweight, cost saving solution to large structural components for rail vehicles in design stages. The sandwich composite train roof was 11.45 meter long and 1.76 meter wide. The reinforced frame was inserted in sandwich panels to improve the structural performance of train roof structure and had the shape of hollow rectangular box. The finite-element analysis was used to calculate the stresses, deflections and natural frequencies of the sandwich composite train roof against the weight of air-condition system. The 3D sandwich FE model was introduced to simulate the hollow aluminum frames which jointed to both sides of the sandwich train roof. The results shown that the structural performance of a sandwich composite train roof under load conditions specified was proven and the use of aluminum reinforced frame was beneficial with regard to weight savings in comparison to steel reinforced frame.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2010년도 춘계학술발표대회
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• pp.78-81
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• 2010

ARINC 653은 통합형 항공전자 시스템에서 사용되는 응용프로그램 간의 인터페이스와 실시간 운영체제의 표준을 정의한다. ARINC 653에 정의되어 있는 네트워크 통신 인터페이스는 대형 항공기뿐만 아니라 무인 비행체와 같은 작은 항공체에도 적용이 가능하다. 이러한 작은 시스템에서는 TCP/IP와 같이 무거운 프로토콜보다는 경량의 실시간 프로토콜이 적합하다. 본 논문에서는 RTDiP을 이용하여 ARINC 653의 통신 인터페이스 중에서 Queuing-mode를 구현하고 성능 측정을 수행한다.

• International Journal of Railway
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• 제2권3호
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• pp.124-126
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• 2009

Energy savings can be achieved with optimum energy consumptions, brake energy regeneration, efficient energy storage (onboard, line side), and primarily with light weight vehicles. Over the last few years, the rolling stock industry has experienced a marked increase in eco-awareness and needs for lower life cycle energy consumption costs. For rolling stock vehicle designers and engineers, weight has always been a critical design parameter. It is often specified directly or indirectly as contractual requirements. These requirements are usually expressed in terms of specified axle load limits, braking deceleration levels and/or demands for optimum energy consumptions. The contractual requirements for lower weights are becoming increasingly more stringent. Light weight vehicles with optimized strength to weight ratios are achievable through proven design processes. The primary driving processes consist of: $\bullet$ material selection to best contribute to the intended functionality and performance $\bullet$ design and design optimization to secure the intended functionality and performance $\bullet$ weight control processes to deliver the intended functionality and performance Aluminium has become the material of choice for modern light weight bodyshells. Steel sub-structures and in particular high strength steels are also used where high strength - high elongation characteristics out way the use of aluminium. With the improved characteristics and responses of composites against tire and smoke, small and large composite materials made components are also found in greater quantities in today's railway vehicles. Full scale hybrid composite rolling stock vehicles are being developed and tested. While an "overdesigned" bodyshell may be deemed as acceptable from a structural point of view, it can, in reality, be a weight saving missed opportunity. The conventional pass/fail structural criteria and existing passenger payload definitions promote conservative designs but they do not necessarily imply optimum lightweight designs. The weight to strength design optimization should be a fundamental design driving factor rather than a feeble post design activity. It should be more than a belated attempt to mitigate against contractual weight penalties. The weight control process must be rigorous, responsible, with achievable goals and above all must be integral to the design process. It should not be a mere tabulation of weights for the sole-purpose of predicting the axle loads and wheel balances compliance. The present paper explores and discusses the topics quoted above with a view to strengthen the recommendations and needs for the weight optimization by design approach as a pro-active design activity for the rolling stock industry at large.