• 한국구조물진단유지관리공학회 논문집
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• 제24권4호
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• pp.38-47
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• 2020

RC 고층건물에서 발생하는 기둥축소의 예측 오차를 최소화하기 위하여 계측결과를 이용한 해석보정에 대한 변수연구가 수행되었다. 해석보정의 변수는 해석보정 시행기준, 해석보정 값, 계측 위치이며, 변수에 따른 해석보정 모델을 41층 규모의 RC 건물의 시공단계해석에서 적용하여 변수에 따른 보정 효과를 비교·분석하였다. 보정 횟수와 전체 보정량에 따른 층별 오차 값의 감소율을 비교하였으며, 해석보정의 시행기준은 일정한 간격을 기준으로 해석보정 할 경우, 해석보정 값은 오차 값만큼 보정할 경우, 계측 위치는 매 층 계측이 될 경우에 오차가 최소화되는 경향을 확인하였다. 이로부터 실제 해석 모델에 대하여 여러 해석보정 모델을 적용함으로써 가장 적합한 해석보정 모델을 도출할 수 있음을 확인하였다.

• 항공우주기술
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• 제12권1호
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• pp.144-151
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• 2013

다목적실용위성 2호(이하 KOMPSAT-2)는 고해상도 1.0m 흑백영상을 촬영할 수 있는 PAN 카메라와 4.0m 다중파장대의 칼라 영상을 수집할 수 있는 멀티스펙스럴 카메라를 탑재하고 있다. 이를 통하여 취득한 위성영상은 국토관리, 농업, 환경, 해양감시 및 GIS등의 광범위한 분야에 활용되고 있다. 본 연구는 KOMPSAT-2 자료를 이용하여 지상좌표를 해석하는 방법과 해석된 지상좌표의 위치정확도를 KOMPSAT-2 시스템 요구사항인 위치정확도를 만족시키기 위해 현재 적용되고 있는 위치정확도 보정계수 산출절차를 정의하는 것을 목적으로 한다.

• Journal of Positioning, Navigation, and Timing
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• 제10권3호
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• pp.189-196
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• 2021

In this paper, we propose techniques to correct the altitude error and heading error of 3D Pedestrian Inertial Navigation (PIN). When a PIN is used to estimate the location of a pedestrian only with an Inetrial Measurement Unit (IMU) without infrastructure, there is a problem in that the location error gradually increases due to the limitation of the observability of the filter. To solve this problem without additional sensors, we propose two techniques in this paper. First, stair walking is recognized in consideration of the altitude difference that may occur during one step. If it is recognized as stair walking, only Zero-velocity UPdaTe (ZUPT) is performed, and if it is recognized as level walking, ZUPT + Altitude Damping (AD) is performed together to correct the altitude error. Second, the straight-line movement direction is calculated through the difference of the estimated position, and the heading error is corrected by matching this information with the link information of the digital map. By applying these techniques, it is verified through real tests that accurate three-dimensional location information of pedestrians can be estimated without infrastructure.

• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3488-3493
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• 2022

Accelerator driven subcritical systems have long been discussed as facilities which can be used for solving the nuclear waste problem. The physics of these systems is very different from conventional reactors and new techniques had to be developed for reactivity monitoring. One such technique is the Area Ratio Method which studies the response of a subcritical system upon insertion of a large number of neutron pulses. An issue associated with this technique is the spatial dependence of measured reactivity which is intrinsic to the sub criticality of the system since the reactor does not operate on the fundamental mode and measured reactivity depends on the detector position. This is generally addressed by defining Bell-Glasstone spatial correction factor. This factor upon multiplication with measured reactivity gives the correct reactivity which is independent of detector location. Monte Carlo Methods are used for evaluating these factors. This paper presents a complete three dimensional map of spatial correction factors for BRAHMMA subcritical system. In addition, the dataset obtained also helps in identifying detector locations where the correction factor is close to unity, thereby implying no correction if the detector is used at those locations.

• 대한원격탐사학회지
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• 제6권1호
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• pp.25-37
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• 1990

Methods of geometric correction for the Advanced Very High Resolution Radiometer imagery of NOAA satellites were developed and applied to the software for image processing of meteorological satellite data. The software for finding the earth location of each scan position and the software for gridding on original imagery were dedigned. On the assumption of circular orbits and the spherical earth, the methods developed were sufficiently accurate in the purpose of most meteorological data analyses.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권3호
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• pp.1087-1104
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• 2015

An eye location based head posture recognition method is proposed in this paper. First, face is detected using skin color method, and eyebrow and eye areas are located based on gray gradient in face. Next, pupil circles are determined using edge detection circle method. Finally, head postures are recognized based on eye location information. The proposed method has high recognition precision and is robust for facial expressions and different head postures, and can be used in mouse operation. The experimental results reveal the validity of proposed method.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(C)
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• pp.258-261
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• 2011

Living in the age of information people face problems related to information overload. Information is easy to produce, store and distribute through various communication channels, one of which is emails. With the appearance of the mobile devices, such as smart phones and tabs, people can have access to email inbox at any moment of time from everywhere. In this paper we present information extraction system with a specific goal of extracting meeting location from the announcement of seminar or conference. We apply a machine learning method (conditional random fields, CRF), train the system using annotated corpus of seminar and conference announcements and validate results by applying various extracted correction rules and patterns. Furthermore, we normalize extracted location, and reference using geo-coding databases, OpenStreetMap and Wikipedia resources to determine real geographical coordinates.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1273-1278
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• 2000

Bridge load rating calculations provide a basis for determining the safe load capacity of bridge. Load rating requires engineering judgement in determining a rating value that is applicable to maintaining the safe use of the bridge and arriving at posting and permit decisions. Load testing is an effective means in calculating the rating value of bridge. In Korea, load carrying capacity of bridge is modified by stress modification factor that is determined from comparisons of measured values and analysis results The stress modification factor may be corrupted by vehicle location error that is defined as the gap of test vehicle location between load testing and analysis. In this study, the effects of vehicle location error to structural response and stress modification factor are investigated, and a new method for evaluating stress modification factor is proposed. The random data analysis shows that the proposed method is less sensitive to vehicle location error than the present method.

• 대한전기학회논문지
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• 제38권3호
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• pp.193-200
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• 1989

The errors of activation energy calculated by the initial rise method from the characteristics of thermally stimulated current have been estimated and an equation for the correction of the error is proposed. The coefficients needed in the proposed equation are determined by the numerical method. It is shown that the activation energy calculated by the conventional initial rise method contains errors of 0.7-10% depending on the location of the data points of the interval on which the method is applied. However, the error can be reduced to less than 0.5% when corrected by using the proposed equation. It is finally concluded that the activation energy determined by the initial rise method can approach the true value by adapting the proposed error correction method which is effective and reliable.

• 전기전자학회논문지
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• 제26권2호
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• pp.186-195
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• 2022

In this paper, we propose a new algorithm to improve the accuracy of indoor positioning techniques using Wi-Fi access points as beacon nodes. The proposed algorithm is based on the Weighted Centroid algorithm, a popular method widely used for indoor positioning, however, it improves some disadvantages of the Weighted Centroid method and also for other kinds of indoor positioning methods, by using the received signal strength correction method and genetic algorithm to prevent the signal strength fluctuation phenomenon, which is caused by the complex propagation environment. To validate the performance of the proposed algorithm, we conducted experiments in a complex indoor environment, and collect a list of Wi-Fi signal strength data from several access points around the standing user location. By utilizing this kind of algorithm, we can obtain a high accuracy positioning system, which can be used in any building environment with an available Wi-Fi access point setup as a beacon node.