• 한국건설관리학회논문집
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• 제4권4호
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• pp.182-191
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• 2003

초고층$\cdot$대형 현장은 일반 현장관리 방법과는 달리 경험에 의한 의사결정에는 한계가 있다. 특히 도심지 고층 공사의 경우 대지의 여유 공간이 협소하여, 자재적치와 수평 동선을 위한 공간의 확보가 용이하지 않다. 이러한 초대형 프로젝트를 수행하기 위해서는 기존 경험에 의존하는 양중 및 조달 관리의 한계성을 인식하고 새로운 양중 및 조달 관리 방법의 모색이 필요하게 되었다. 따라서 JIT의 개념을 도입하는 것이 필수적이라 하겠다 현장 내 즉, 반입 이후의 단계는 물리적인 자재의 흐름보다는 정보의 흐름과 의사소통이 중요시되는 단계로 본 연구에서는 현장 내 물류흐름의 문제점을 분석하여, 자재별 속성을 고려한 양중계획수립, 작업일정과 양중일정의 통합관리, 자재의 위치현황 및 작업의 설치현황 가시화를 통한 정보의 공유, 계획대비 실적의 평가의 부분을 시스템개발 방향으로 설정하여. 커뮤니케이션 도구로서의 역할과 계획 대비 실적 평가를 통한 계획의 신뢰도 확보 등을 주요 기능으로 하는 양중관리시스템을 개발하였다.

• International Journal of Aeronautical and Space Sciences
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• 제18권1호
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• pp.154-164
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• 2017

This work conducts a validation study for the XH-59A helicopter using a rigid coaxial rotor system in order to establish the techniques of the conceptual design and performance analysis for the lift-offset compound rotorcraft. As a tool for conceptual design and performance analysis, NDARC (NASA Design and Analysis of Rotorcraft) is used for the present study. An assumed mission profile is considered for the conceptual design of the XH-59A. As a validation result of the design, the dimensions and weight of the XH-59A are appropriately designed when compared to the target values since the relative error is less than 0.5%. Then, performance analyses are conducted for the designed XH-59A model with and without auxiliary propulsion in hover and forward flight conditions. The present analyses show good validity since the prediction results compare well with both the flight test and previous analyses. Therefore, the techniques for the conceptual design and performance analysis of the lift-offset compound helicopter are overall considered to be appropriately established. In addition, this study investigates the influence of the lift-offset on the rotor effective lift-to-drag ratio of the XH-59A helicopter with auxiliary propulsion. As a result, the improvement of the rotor effective lift-to-drag ratio can be obtained by appropriately increasing the lift-offset in high-speed flight.

• 대한조선학회논문집
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• 제47권4호
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• pp.533-542
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• 2010

For a long times it has been believed that the Magnus effect of the rotating cylinder could be utilized for the lifting devices applicable to marine practices. It has been reported that the rotating cylinder installed on upper deck of commercial vessel could play a energy saving role however the idea might be applicable in a very rare case in ship building practices. In this study special high lift rudder system equipped with the trailing edge rotor has been suggested in correspondence with the increasing requirement of greater rudder force. Through the numerical simulation it is cleared that the trailing edge rotor could play a role in enhancement of circulation and refinement of boundary layer of the rudder system. At the same time it is found out that the lift force of the rudder system without rotation of trailing edge rotor could be doubled when the circumferential velocity of the trailing edge rotor is equal to twice of the inflow velocity.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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• pp.539-542
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• 2004

최근 건축물의 대형화, 고층화 경향에 따라, 현장에서 취급되는 자재의 종류는 갈수록 다양해지며, 자재의 양도 방대해 지고 있다. 세분화된 공정으로 인해 서로 다른 공정이 동시 다발적으로 진행되기 때문에 현장에서 작업동선 및 물류의 이동이 매우 복잡해진다. 이에 따라, 효율적인 자재 반입 및 양중이 필요하다. 특히 마감 공사 시에 마감자재와 설비자재와의 반입 충돌과 공정상의 불일치로 인해 건물에 양중 문제가 발생하고 있다. 본 논문은 이를 분석하고 문제점에 영향을 미치는 요소들을 파악하여 효과적인 자재 양중방향을 제시한다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 춘계학술대회
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• pp.364-366
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• 2017

해양플랜트는 일반 선박과는 달리 작업이 진행되면 고정된 위치에서 장시간 운용되는 특성으로 인하여 높은 신뢰성을 요구하고 있으며 안전 확보를 위하여 사용자 및 유지보수 작업자에게 센서 기반 상태 정보가 필요하다. 본 논문에서는 해양플랜트용 Cargo Lift에 대한 안전진단 및 점검을 위한 모니터링 시스템을 제안한다. 해양플랜트 Cargo Lift에 탑재된 센서부와 임베디드 시스템 계측부, 실시간 데이터 확인을 위한 모니터링부로 구성되며 조선해양 분야에서 장비들의 고도화 및 통합화에 따라 승강기에 대한 운행정보 및 센서 계측 정보의 교환을 위해 선박 표준 네트워크 IEC 61162-450을 기반으로 한다.

• 국제초고층학회논문집
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• 제11권2호
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• pp.125-135
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• 2022

While buildings in recent days become taller and larger, many problems occur during the management of construction. Particularly, as the vertical movement of manpower and materials during construction has become longer while the lifting frequency and load increase, the need for a good lifting management practice is also increasing. Therefore, this study presents a real-time lifting performance monitoring system that can store and manage lifting records for construction management. Through review of literature and preceding studies related to construction lift, the concept of lift planning and operation management was understood, leading to the development of a system to monitor lifting operation and performance information. This system enabled quick measurement of the lifting performance during construction phase while responding to changes in the project schedule. To verify this system, a case study was conducted in which the current status and characteristics of the sensing-based lifting performance were derived.

• 국제초고층학회논문집
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• 제8권3호
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• pp.185-192
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• 2019

Citic Tower is the first over-500 m-tall super highrise building in the world, located in the high seismic intensity area with paek ground acceleration over 0.2g in 475 years. This project is unique in its complexity, large volume, and challenging site conditions (zero site for construction). The traditional techniques can hardly meet safty, quality and schedule requirements of the construction. This article introduces the key construction technologies that are innovatively developed and applied in Citic Tower project construction, including intelligent super-high-rise building integrated construction platform system, independently developed by the CCTEB; Jump-Lift Elevator, which is the first of the kind with service height over 500 meters; combined temporary-and-permanent fire protection systems. The BIM technology is also applied in this project. Through technical innovation, and utilization of technologies, construction speed and safety had been greatly improved.

• 한국산업융합학회 논문집
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• 제23권4_1호
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• pp.559-567
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• 2020

As the renewable energy market grows, grid-connected inverters have been improving and expanding in several fields in recent years because energy conversion devices are the main components of solar systems. In this paper, a high-precision new grid-connected three-phase inverter system is proposed. The proposed system consists of a main inverter, a sub inverter and a transformer. The main inverter operates at a low switching frequency and high power and transmits power to the grid. A sub-inverter connected in series with the transmission line through a matching transformer operates at lower power than the main inverter to provide input values to the transformer. The transformer acts as a power supply according to the voltage compensation value. This study is based on the principle of operation of the UPFC(Unified Power Flow Controller) structure used to regulate power flow in AC transmission lines. The grid-connected inverter system proposed in this paper is implemented with high precision and high resolution. The proposed system was verified through its ability to enhance and ensure the safety of the proposed system through simulation and experiment.

• 한국전산유체공학회지
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• 제21권4호
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• pp.85-89
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• 2016

Wing is the most important part of aircraft which produces lift. In general when aircraft takes off or lands, high lift is required and additional devices are adopted in front and aft-side of wing, which constitute so-called multi element airfoils. The objective of this research is to develop a specialized grid generation program to help engineers in reducing human labor and eliminating time-consuming process for mesh regeneration by deforming the initially-given grid system with efficient deforming method. This paper describes briefly about the mesh deformation methods, and provides some results to verify the quality of deformed mesh and eventually correctness of current approach.

• 한국건설관리학회논문집
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• 제13권2호
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• pp.110-119
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• 2012

초고층 건축물의 수요가 늘어나면서 수직 양중 계획과 장비에 대한 중요성이 증대되고 있으며, 경제적이고 효율적인 리프트 사용을 위하여 무인 리프트의 사용 비중이 늘어나고 있다. 하지만 리프트의 정지위치 에러가 발생하거나 누적되는 경우 작업 효율성이 떨어지고, 문제 해결을 위해 리프트 업체가 리프트를 재 세팅 하는 동안 리프트 사용이 불가하게 되어 공사 진행에 장애가 된다. 본 연구에서는 리프트 정지위치 에러에 의한 시간 및 비용 손실을 방지하기 위해 리프트 정지위치 감지장치를 개발하였다. 실험을 통해, 정지위치 에러 발생 시 이를 보정하는 기능을 검증하였고, 정확도도 약 9.75mm 증가하는 것을 확인하였다.