• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.395-400
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• 2001

건설공사의 성공적인 수행을 위해서는 프로젝트의 성과에 대한 주기적이고 반복적인 측정 및 그에 대한 조치가 필요하다. 이에 비용, 일정, 품질은 프로젝트 성과 측정의 주요 대상이 되며, 비용 및 일정의 경우 정량화할 수 있고, 상호연관성이 높기 때문에 통합관리의 필요성이 매우 높다. 이러한 비용일정 통합관리를 통한 성과측정 방법이 바로 EVMS이며, 이러한 새로운 관리방식의 성공적인 국내적용을 위해선 그 관리 방법의 절차 및 의미가 명확히 인식되어야 한다. 이에 본 연구는 비용, 일정, 여유시간을 종합적으로 고려한 새로운 최적의 성과측정기준선(Performance Measurement Baseline)설정 및 진도율 산정 방법을 제시하고자 한다. 제시된 방법을 통해 비용 및 일정정보가 통합된 성과측정기준선이 마련되었으며, 진도율 산정에 있어서도 작업간 영향요소 및 공기지연가능성을 고려한 종합적인 작업별 가중치가 산정되었다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.513-516
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• 2008

건설프로젝트는 많은 불확정 요소로 인해 다양한 리스크를 가지고 있기 때문에 프로젝트 진행 과정에서 반복적인 성과측정은 중요하다. 그러나 현재 건설프로젝트에서 성과측정은 시공사 중심의 성과측정 및 성과관리가 이루어 져서 프로젝트의 진행상황에 따른 발주자의 능동적인 프로젝트 관리가 어렵다. 이에 본 연구에서는 실제 실행된 공공 아파트 건설공사의 공기 비용 데이터를 타입별로 분류하여 회귀분석을 실시하고 타입별 회귀식을 도출, 발주자 중심의 작업분류체계를 설정하고 이를 활용하여 이를 발주자 중심의 성과측정기준선을 제안방안을 제시하고자 한다.

• International Journal of Control, Automation, and Systems
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• 제4권3호
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• pp.333-343
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• 2006

In this paper, the baseline-length information is directly modeled as a measurement for the Wald test, which speeds up the resolution convergence of the integer ambiguity of GPS carrier phase measurements. The convergent speed improvement is demonstrated using numerical simulation and real experiments. It is also shown that the integer ambiguities can be resolved using only four actual satellite measurements with very reasonable convergence speed, if the baseline-length information is used just like one additional observable satellite measurement. Finally, it is shown that the improvement of convergence speed of the Wald test is due to the increase of the probability ratio with the use of the baseline-length constraint.

• 한국소음진동공학회논문집
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• 제11권5호
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• pp.108-122
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• 2001

As bridge design is advancing toward the performance-based design. it becomes increasingly important to monitor and re-evaluate the long-term structural performance of bridges. Such information is essential in developing performance criteria for design. In this research. sensor systems for long-term structural performance monitoring have been installed on two highway bridges. Pre1iminary vibration measurement and data analysis have been performed on these instrumented bridges. On one bridge, ambient vibration data have been collected. based on which natural frequencies and mode shapes have been extracted using various methods and compared with those obtained by the preliminary finite element analysis. On the other bridge, braking and bumping vibration tests have been carried out using a water truck In addition to ambient vibration tests. Natural frequencies and mode shapes have been derived and the results by the breaking and bumping vibration tests have been compared. For the development of a three dimensional baseline finite element model, the new methodology using a neural network is proposed. The proposed one have been verified and applied to develop the baseline model of the bridge.

• 한국항공우주학회지
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• 제42권6호
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• pp.453-460
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• 2014

본 논문에서는 위성항법시스템의 무결성 저해 요인 중, 항법메시지에 담겨 전송되는 궤도력 (Ephemeris) 정보의 고장 여부를 판단할 수 있는 알고리즘을 분석 및 성능 평가를 수행하였다. 알고리즘은 반송파 측정값과 두 지상 기준국간의 기저벡터 정보가 활용된다. 주요 특징으로 기준국 기저선과 위성이 이루는 기하학적 조건 기저선 길이에 따라 동일 궤도력 고장에 대해 알고리즘의 성능의 편차가 발생할 수 있음을 확인하였다. 또한 알고리즘 적용이 적합한 GBAS의 지상 기준국 안테나 배치 방안 및 제주국제공항에 운용되었을 때의 한계치 및 성능 지표 (MDE : Minimum Detectable Error)를 계산하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.23-26
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• 2006

Modernized GPS will have three frequencies modulated with three signals, which will be accessible to all users in the near future. This new frequency provides an opportunity to resolve the double differenced (DD) integer ambiguity very fast and with almost no baseline constraints. In order to study the performance of triple frequency system for Ambiguity Resolution (AR) over the medium baseline under different ionospheric levels, the Klobuchar Model was implemented and used in our triple simulation to generate the ionospheric delay. Furthermore, the White-Gaussian noise applying to distance-dependent parameters was added to the DD ionospheric delay. For medium baseline (defined as here 20 to 40kms), success rates of AR has been pretty improved. In this paper, the medium baseline AR strategies that take advantage of carrier phase measurement on the third frequency will be discussed.

• Journal of Positioning, Navigation, and Timing
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• 제10권3호
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• pp.159-168
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• 2021

Precise Point Positioning-Real Time Kinematic (PPP-RTK) is an improved PPP method that provides the user receiver with satellite code and phase bias correction information in addition to the satellite orbit and clock, thus enabling single-receiver ambiguity resolution. Single station PPP-RTK concept is special case of PPP-RTK in that corrections are computed, instead of a network, by only one single GNSS receiver. This study is performed to experimentally verify the positioning accuracy performance of single baseline RTK level by a user who utilizes correction for a single station PPP-RTK using dual frequencies. As an experimental result, the horizontal and vertical 95% accuracy was 2.2 cm, 4.4 cm, respectively, which verify the same performance as the single baseline RTK.

• 한국군사과학기술학회지
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• 제9권2호
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• pp.60-69
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• 2006

The PMB(performance measurement baseline) is the total time-phased budget plan against which program performance is measured. Additionally it is the schedule for expenditure of the resources allocated to accomplish program scope and schedule objectives, and is formed by the budget assigned. In this paper, we suggest an improvement of the R & D(research and development) program for defense acquisition by using the PMB and an application of the IBR(integrated baseline review) to review the PMB for project manager of the defense agency.

• 제어로봇시스템학회논문지
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• 제19권8호
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• pp.702-708
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• 2013

Underwater TRN (Underwater Terrain Referenced Navigation) estimates an underwater vehicle state by measuring a distance between the vehicle and undersea terrain, and comparing it with the known terrain database. TRN belongs to absolute navigation methods, which are used to compensate a drift error of dead reckoning measurements such as IMU (Inertial Measurement Unit) or DVL (Doppler Velocity Log). However, underwater TRN is different to other absolute methods such as USBL (Ultra-Short Baseline) and LBL (Long Baseline), because TRN is independent of the external environment. As a magnetic-field-based navigation, TRN is a kind of geophysical navigation. This paper develops an EKF (Extended Kalman Filter) formulation for underwater TRN. A filter propagation part is composed by an inertial navigation system, and a filter update is executed with echo-sounder measurement. For large-initial-error cases, an adaptive EKF approach is also presented, to keep the filter be stable. At the end, simulation studies are given to verify the performance of the proposed TRN filter. With simplified sensor and terrain database models, the simulation results show that the underwater TRN could support conventional underwater navigation methods.

• 제어로봇시스템학회논문지
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• 제11권7호
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• pp.621-626
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• 2005

With precise GPS carrier positioning result, we can get attitude information if GPS antenna has adequate attaching position on the vehicle. In this case, baseline length information can be bandied as an additional measurement or constraint. In this paper, we have proposed a method to improve the attitude accuracy. To overcome nonlinearity of baseline observation model, we analyze attitude estimation result using existing estimation method like a least square method and Kalman filter, and apply a new nonlinear estimation method an unscented Kalman filter Finally we confirm the improvement of attitude estimation result in the case of appling the unscented Kalman filter.