• 제목/요약/키워드: structure improvement

검색결과 4,051건 처리시간 0.037초

구조적 성능 향상을 위한 철차 하부 지지틀의 고찰 (The Review of Underframe Structure to Improving Structual Performance)

  • 최원호;김운호;엄경수
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1571-1577
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    • 2007
  • Nowadays stronger rules are applied to rolling stocks because of improvement of standards and thoughts to safety. So the designing lightweight rolling stock underframe structure is required to these rules. This review is about underframe structure which satisfies the condition of AAR Longitudinal static compressive force 360 ton comparing with difference of the former underframe structure.

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자산재평가와 재무구조 (Asset Revaluation and Financial Structure)

  • 황동섭
    • 산업경영시스템학회지
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    • 제22권52호
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    • pp.221-228
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    • 1999
  • The purpose of this paper is to see whether the improvement on the financial structure through the asset revaluation is temporary or not. The financial structure of the companies which revalue the asset was improved for the revaluating year, but the financial structure worsened in the next year. Therefore, I can infer that the asset revaluation is carried out to supply their capital by enterprises.

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철도교량의 개량계획 설정에 관한 연구 (A Study on establishing Improvement Plan of Rail Bridges)

  • 백재욱;박대효
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.10-16
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    • 2008
  • In order to improve stability of rail and ride comfort, railway bridges should be maintained a integrity. However, it is necessary to plan various reinforcements and improvements because of a long term used and external effects. In this paper, the improvement plan which is reflected by investigation for reinforcement and improvement is introduced. The constituents of the structures are defined in order to optimize the improvement plane, and the analysis for relationships between the constituents are performed by several evaluation. Finally, the improvement plan is applied to a structure using impact factors for the external effects in order to obtain the improvements reasonably.

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ARS(자동응답시스템) 정보 구조에 관한 연구 -김해 버스정보시스템 ARS 개발을 중심으로- (A Study on Structure of Information about ARS(Automatic Response System) - with Emphasis on the Development of Gimhae Bus Information System ARS -)

  • 류수민;이춘엽;연명흠
    • 한국HCI학회:학술대회논문집
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    • 한국HCI학회 2008년도 학술대회 2부
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    • pp.370-375
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    • 2008
  • 전화를 걸었을 때 기존의 각종 안내 서비스나 전문 서비스를 자동화하여 사용자가 원하는 안내정보를 시간과 장소에 구애 받지 않고 다양한 형태로 제공해주는 ARS(자동응답시스템)의 영역이 확대되고 있으며, ARS의 이용률 또한 높은 편이다. 하지만, ARS의 중요도에 비해 실제 사용자에게 가장 근접한 정보 구조의 연구는 거의 없는 실정이다. 따라서 본 연구는 김해 버스정보시스템(BIS) ARS의 정보 구조에 관한 것으로, ARS의 정보 구조상 문제점을 분석하여 개선안을 제안한 후, 이를 평가하여 최종 개선안을 제시하는 것을 목적으로 한다. 연구방법으로는 ARS의 상태도를 작성하고 사용자 관찰을 실시하였으며, 다른 지역의 사례를 비교, 분석하였다. 그 결과, 전반적인 정보구조상의 오류가 있어 체계적인 시스템의 개선이 요구되었다. 이를 바탕으로 두 가지 개선안을 제안하였으며, 두 가지 개선안을 바탕으로 사용성 평가를 실시하였다. 사용성 평가는 실험실 평가로 진행 되었으며, 인터뷰를 병행하였다. 그 결과 두 가지 개선안의 장단점을 파악할 수 있었고, 최종 개선안은 두 가지 개선안의 장점만을 부각시켜 완성하였다. 본 연구는 차후 김해BIS의 ARS를 개선하는 데 기초 자료로 활용될 것이다.

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입구 개방형 덕트를 적용한 초저낙차 횡류수차의 성능향상 (Performance Improvement of Very Low Head Cross Flow Turbine with Inlet Open Duct)

  • 천쩐무;패트릭 마크 싱;최영도
    • 한국유체기계학회 논문집
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    • 제17권4호
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    • pp.30-39
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    • 2014
  • The cross flow turbine is economical because of its simple structure. For remote rural region, there are needs for a more simple structure and very low head cross flow turbines. However, in this kind of locations, the water from upstream always flows into the turbine with some other materials such as sand and pebble. These materials will be damage to the runner blade and shorten the turbine lifespan. Therefore, there is a need to develop a new type of cross flow turbine for the remote rural region where there is availability of abundant resources. The new design of the cross flow turbine has an inlet open duct, without guide vane and nozzle to simplify the structure. However, the turbine with inlet open duct and very low head shows relatively low efficiency. Therefore, the purpose of this study is to optimize the shape of the turbine inlet to improve the efficiency, and investigate the internal flow of a very low head cross flow turbine. There are two steps to optimize the turbine inlet shape. Firstly, by changing the turbine open angle along with changing the turbine inlet open duct bottom line (IODBL) location to investigate the internal flow. Secondly, keeping the turbine IODBL location at the maximum efficiency achieved at the first step, and changing the turbine IODBL angle to improve the performance. The result shows that there is a 7.4% of efficiency improvement by optimizing turbine IODBL location (open angle), and there is 0.3% of efficiency improvement by optimizing the turbine IODBL angle.

충격흡수용 복합부재의 에너지 흡수특성에 관한 유한요소해석 (Finite Element Analysis on the Energy Absorption Characteristics of Hybrid Structure)

  • 신현우
    • 한국자동차공학회논문집
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    • 제12권5호
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    • pp.101-107
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    • 2004
  • Recently the objective of vehicle design was focused on the crash safety and the energy saving. For the energy saving vehicle structures must be light weight, but for the crash safety some energy absorbing elements must be added. In this paper hybrid structure which consists of a steel and a FRP was studied on the energy absorption characteristics under the impact load by finite element method. Test results of the other researchers were compared with that of computer simulation on this simple hybrid structure. Side rail of vehicle front structure was replaced with hybrid materials for the application of the vehicle structure. 35mph frontal crash simulation was performed with hybrid structure and with conventional steel structure. By the adoption of hybrid structure, the improvement of energy absorption characteristics and reduction of weight was observed under the frontal crash simulation.

AC PDP의 효율 향상을 위한 비대칭형 금속전극구조 (Improvement of Luminous Efficacy in AC PDP with Asymmetric Metal Electrode Structure)

  • 동은주;옥정우;윤초롬;이해준;이호준;박정후
    • 전기학회논문지
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    • 제57권4호
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    • pp.660-667
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    • 2008
  • To improve the luminous efficacy of PDPs, an AC PDP with new metal electrode structure is suggested. Operating voltage margin, power consumption, luminance, luminous efficacy, addressing jitter and ICCD image of test panel with proposed structure are measured, to compared with performances of the conventional ITO structure and proposed structures. To enhance luminous efficacy, we designed new structure which have asymmetric metal electrode structure. The experimental results show that the suggested structure shows luminance to maximum 89% and luminous efficacy to maximum 107% compared with conventional ITO standard structure. In addition, proposed structures with asymmetric electrode show low power consumption by $2{\sim}3%$, high luminance by $5{\sim}7%$, and high luminous efficacy by $2{\sim}3%$ compared with proposed symmetric electrode structures.