• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.855-858
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• 2008

The lightweight bubble mixture soil are lightweight soft ground rear, which is used with the material filling. However, comparing with the general soil, it is not valuably useful from domestic. The utilization of the general soil which initial public corporation holds mainly few. The overlay method of general soil decreasing the number of layers increases according to use research study. From the research which consequently, BOX mechanical behavior materials rear executed LCC analyses the general soil which is a material filling and lightweight bubble mixture soil, discussed two kind alternatives and presents the analysis will be able to support the decision-making which is rational from the economics. The expense, which results from the resultant of lightweight bubble mixture soil maintenance, was fewer and was then analyzed with the fact that, will be able to secure an economical efficiency within 6 years.

• Korean Journal of Construction Engineering and Management
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• v.10 no.6
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• pp.40-47
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• 2009

The lightweight bubble mixture soil is used for soft ground rear-filling material by applying reduced weight on structure. However, comparing with the general soil, it is not applied in domestic because of initial phase cost of construction. General soil, which has lower initial phase cost is usually used for rear-filling, but the use of overlay method of general soil is reduced as the number of layers increases. Especially box structure placed in soft ground or the overlay method when gap near pier rear-filling can be replaced with temporary alternative method, however, it can't be a solution to gap by generation of extra weight of thickness of overlaying. Therefore, execute LCC analysis of two alternative-the general and the lightweight bubble mixture soils, which are rear-filling material of box structure- and present economical analysis in order to make resonable decision from the economics. As a result, although the lightweight bubble mixture soil takes higher initial phase cost than the general soil, it has been analyzed to procure economical efficiency by having less cost of maintenance.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.169-171
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• 2003

최근 환경문제가 대두됨에 따라 산업폐기물의 처리문제에 많은 관심과 연구가 진행되고 있다. 또한 현대의 콘크리트 구조물은 거대화, 고층화되어 그 중량이 계속 커지고 있으므로 구조물을 경량화 하려는 노력과 개발이 계속 진행되어 왔다. 구조물의 주재료로 사용되고 있는 콘크리트는 강도 및 내구성에 비해 비중이 크다는 결점을 가지고 있으므로 강하고 가벼운 고강도의 경량골재 콘크리트 개발이 행해져 왔다. (중략)

• Journal of the Korean Geotechnical Society
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• v.21 no.4
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• pp.21-29
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• 2005

Lightweight Foamed Soil (LWFS) could be the substitute of normal soils used in backfill to earth structures and embankment materials far soft ground improvement in port and harbor project because of its effectiveness in settlement reduction and earth pressure decrease due to its lightness. A series of triaxial and unconfined compression tests were performed to investigate behaviors of LWFS composed of dredged soils, cement and air foam, and cured at underwater conditions. The density of LWFS will increase if LWFS is cured at underwater conditions because high water pressure makes air foam disappear or demolish during the curing compared with LWFS cured at normal air conditions. This paper is to find the mechanical behaviors of LWFS cured at seawater depth of 5.0 m and 10.0 m, respectively, which simulates underwater curing conditions by underwater pressure simulator chamber developed during this study. In addition, new normalized factor formula, which takes account of mixing design conditions determining compressive strength of LWFS, was proposed to consider mixing design factor fur LWFS.

• Journal of the Society of Disaster Information
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• v.7 no.1
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• pp.21-31
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• 2011

The objectives of this study is replaced Silicafume with Metakaolin that is used to lightweight concrete to better performance. So, this study made high-performance lightweight concrete using Metakaolin and characteristics of the fundamental properties and chloride ion diffusion. Consequently, it is compressive strength and chloride ion penetration resistance is lower than lightweight concrete using Silicafume, the performance of compressive strength contrast Silicafume is about 88 to 95%. Also, this study got a content result because the chloride ion penetration resistance showed the performance in around 80 to 90%. As a result, this study insist that replacement ratio of Metakaolin is suitable for 10 to 15%.Silicafume and Metakaolin have similar characteristics. In addition, it is similar to the performance of alternative materials is possible.

• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.39-41
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• 2015

본 논문은 경량항공기에 사용되는 MFD의 판독성 및 가시성을 비교/분석한 것이다. 설문조사를 통해 현재 경량항공기 Cessna Citation Mustang 및 Cessna 172에 사용되는 Garmin사의 G1000과 개발 MFD와 비교/분석 하였다. 설문의 신뢰를 높이기 위해 항공 관계자들을 통해 데이터 수집이 이루어졌으며 정확성, 신뢰성, 적절성, 접근성, 주목성, 분별성, 사실성, 효율성, 디자인 등의 평가요인으로 질문을 작성 수집된 데이터를 통해 평가 및 비교/분석이 이루어 졌다. 수집된 데이터를 통해 기존의 상용 MFD와 개발 중에 있는 MFD를 비교함으로 개발 중인 MFD의 장단점을 분석하여 개발에 더 나은 방향을 제시 할 것이다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.20-20
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• 2012

최근, 수송기기 분야는 국제 환경규제 강화에 따른 CO2 절감, 연비향상, 경량화를 위한 기술적 수요가 증대되고 있으며, 그린카, 그린선박 등 친환경 수송기기에 대한 연구가 활발히 진행되고 있다. 하지만, 기존의 금속소재가 가지는 경량화의 한계를 극복하기 위해서는 CFRP, GFRP 등 금속대체 복합소재를 적용한 수송용 경량부품 개발에 대한 필요성이 요구되고 있다. 복합소재는 섬유사이에서 응력을 전달하는 기지(Matrix)와 하중을 전달하는 섬유(Fiber)의 종류와 양 및 적층 각도에 따라 수송용 부품에 적합한 기계적 특성을 얻을 수 있고, 높은 비강도와 비강성의 값을 갖게 되어 경량화가 용이한 장점이 있다. 반면, 섬유재의 종류, 성형방법, 경화온도 등에 따라 물리적 특성에 큰 변화가 발생하며, 수지의 경화조건에 따라 성형시간이 많이 소요되는 단점을 가지고 있다. 따라서, 본 연구에서는 자동차, 선박, 항공기, 철도차량 등 각종 수송기기의 경량화를 목적으로 생산성 향상 및 성형시간 절감을 위해 열가소성 수지, 저온속경화 수지를 적용하여, 경화 시간을 단축시키고, 3D-fabric 및 다층구조 직물을 Vacuum Infusion 공법으로 성형하여, 기존의 섬유재 적층시 소요되는 작업 공정을 간소화 할 수 있도록, 고속성형 복합소재를 적용한 수송용 경량부품 개발에 관한 연구를 수행하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.425-428
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• 2008

To use lightweight aggregate concrete with the structural material, it was need to evaluate property of mechanic and drying shrinkage and creep of the lightweight aggregate concrete, but these weren't. So the purpose of this study which it sees follows the mechanical property of the eco lightweight aggregate concrete according to the water binder ration in the high strength concrete. Eco lightweight aggregate was made with clay and crushed rock in this study. To make experiment, water binder ratio was divided 35% and 39%. And the fresh concrete properties were that slump flow was 500${\pm}$50mm, air contents was 2.0${\pm}$1.0%. It evaluated the hold a drying shrinkage and the creep the effect, it analyzed quality and reliability of the eco lightweight aggregate concrete.

• The Korean Journal of Air & Space Law and Policy
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• v.33 no.1
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• pp.175-204
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• 2018

Recently, the aviation leisure business has been legislated, and related industries have become active base with increasing the light sports aircraft within the legislation system. However, in the light sports aircraft safety problem, it is often mentioned that the flight is in violation of the regulations, the lack of safety consciousness of the operator and lack of ability, and the personal operators have a risk of accident of light aircraft such as insufficient safety management and poor maintenance. At present, the maintenance of light sports aircraft is carried out by the A & P mechanic in accordance with the relevant laws and regulations, but it is difficult to say that it is equipped with qualification and expertise. It is not a legal issue to undertake light sports aircraft maintenance work on the regulation system. However, the problem of reliability and appropriateness is constantly being raised because airplanes, light sports aircraft, and ultra-light vehicle are classified and serviced in a legal method. Although legal and institutional frameworks for light sports aircraft are separated, much of it is stipulated in the aviation law provisions. Light sports aircraft maintenance work also follows the current aircraft maintenance system. In the United States, Europe, and Australia where General Aviation developed, legal and institutional devices related to maintenance of light aircraft were introduced, and specialized maintenance tasks are covered in the light aircraft mechanics system. As a result of analysis of domestic and foreign laws and regulations, it is necessary to introduce the qualification system for maintenance of light aircraft. In advanced aviation countries such as the United States, Europe, and Australia, a light sports aircraft repairman system is installed to perform safety management. This is to cope with changes in the operating environment of the new light sports aircraft. This study does not suggest the need for a light aircraft repairman system. From the viewpoint of the legal system, the examination of the relevant laws and regulations revealed that the supplementary part of the system is necessary. It is also require that the necessity of introduction is raised in comparison with overseas cases. Based on these results, it is necessary to introduce the system into the light aircraft repairman system, and suggestions for how to improve it are suggested.

• Journal of the korean Society of Automotive Engineers
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• v.16 no.4
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• pp.23-31
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• 1994

이상에서 자동차용 경량재료의 개발동향에 대 해 칸략히 서술하였다. 국내외에서 자동차 경량 화에 적합한 새로운 경량재료개발올 위해 많은 연구가 진행되어 다양한 가능성을 보여주었다. 현재 차동차 경량화에 대한 요구는 펼연적이며, 대체재료에 적합한 재료시스템을 확립하기 위해서는 신소재외 기계적 생질을 비롯한 여러 특성 평가를 위한 공정한 기법을 정립하고 재활용가능성, 설계를 위한 신뢰성 구축 그리고 수급안 정성이 흉족회어야 하며, 또한 특히 기존재료와 비교해서 우수하여야 할 것이다. 이런면에서 국 내의 각 대학, 연구소 및 기업체에서는 경량재료에 대한 연구를 나름대로 충실히 수행하고 있으나, 그 실적은 아직 미미한 상태이며, 장차 보다 훌흉한 연구결과룰 기대하고 이를 바탕으로 세계 자동차분야에서의 경쟁력을 배가시키기 위해서는 범 국가적인 관심과 연구개발투자가 요구한다.