• Journal of Korean Society of Transportation
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• v.23 no.5 s.83
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• pp.135-146
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• 2005

Up to now studies on the fusion of travel time from various detectors have been conducted based on the variance raito of the intermittent data mainly collected by GPS or probe vehicles. The fusion model based on the variance ratio of intermittent data is not suitable for the license plate recognition AVIs which can deal with vast amount of data. This study was carried out to develop the fusion model based on travel time acquired from the license plate recognition AVIs and the point detectors. In order to fuse travel time acquired from the point detectors and the license plate recognition AVIs, the optimized fusion model and the proportional fusion model were developed in this study. As a result of verification, the optimized fusion model showed the superior estimation performance. The optimized fusion model is the dynamic fusion ratio estimation model on real time base, which calculates fusion weights based on real time historic data and applies them to the current time period. The results of this study are expected to be used effectively for National Highway Traffic Management System to provide traffic information in the future. However, there should be further studies on the Proper distance for the establishment of the AVIs and the license plate matching rate according to the lanes for AVIs to be established.

• Journal of the Korea Convergence Society
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• v.6 no.1
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• pp.1-5
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• 2015

In this paper, we describe the design of a fusion labeling system which is controlled by the Wi-Fi signals. The Current labeling system which is used in the industry is designed to work independently on the production line not connected with internet network services. For such reasons, it is very inconvenient for the labeling system to transfer such labeling data of the production line to the server computer. We propose a labeling system connected to the Wi-Fi service being able to send real-time transmission of labeling data. This system can supply the labeling data of production line to the server computer in realtime and improve the production quality than the existing system.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2357-2360
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• 2002

For the satisfying performance of a oil lubricator, design of a oil controller for the system which meets the required specifications and its supporting hardware that keep their functioning is important. Among the hardware of a control system, oil system are most vulnerable to malfunction. Thus it is necessary to keep track of accurate and reliable oil readings for good fusion oil lubricator performance. In case of oil lubricator, data loss, ssr trigger error faults, they are detected by examining the data system output values and the major values of the system, and then the faults are recognized by the analysis of symptoms of faults. If necessary electronic-sensor values are synthesized according to the types of faults, and then they are used for the controller instead of the raw data. In this paper, a fast-32bit cpu microprocessor applied to the control of flexible link system with the sensor fault problems in the error modulo for exact positioning to show the applicability. It is shown that the fusion oil lubricator can provide a satisfactory loop performance even when the sensor faults occure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.137-140
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• 2002

For the satisfying performance of a oil lubricator, design of a oil controller for the system which meets the required specifications and its supporting hardware that keep their functioning is important. Among the hardware of a control system, oil system are most vulnerable to malfunction. Thus it is necessary to keep track of accurate and reliable oil readings for good fusion oil lubricator performance. In case of oil lubricator, data loss, ssr trigger error faults, they are detected by examining the data system output values and the major values of the system, and then the faults are recognized by the analysis of symptoms of faults. If necessary electronic-sensor values are synthesized according to the types of faults, and then they are used for the controller instead of the raw data. In this paper, a fast-32bit cpu micorprocessor applied to the control of flexible link system with the sensor fault problems in the error module for exact positioning to show the applicability. It is shown that the fusion oil lubricator can provide a satisfactory loop performance even when the sensor faults occure

• Korean Journal of Remote Sensing
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• v.10 no.2
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• pp.37-48
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• 1994

In spatial information processing, particularly in non-renewable resource exploration, the spatial data sets, including remote sensing, geophysical and geochemical data, have to be geocoded onto a reference map and integrated for the final analysis and interpretation. Application of a computer based GIS(Geographical Information System of Geological Information System) at some point of the spatial data integration/fusion processing is now a logical and essential step. It should, however, be pointed out that the basic concepts of the GIS based spatial data fusion were developed with insufficient mathematical understanding of spatial characteristics or quantitative modeling framwork of the data. Furthermore many remote sensing and geological data sets, available for many exploration projects, are spatially incomplete in coverage and interduce spatially uneven information distribution. In addition, spectral information of many spatial data sets is often imprecise due to digital rescaling. Direct applications of GIS systems to spatial data fusion can therefore result in seriously erroneous final results. To resolve this problem, some of the important mathematical information representation techniques are briefly reviewed and discussed in this paper with condideration of spatial and spectral characteristics of the common remote sensing and exploration data. They include the basic probabilistic approach, the evidential belief function approach (Dempster-Shafer method) and the fuzzy logic approach. Even though the basic concepts of these three approaches are different, proper application of the techniques and careful interpretation of the final results are expected to yield acceptable conclusions in cach case. Actual tests with real data (Moon, 1990a; An etal., 1991, 1992, 1993) have shown that implementation and application of the methods discussed in this paper consistently provide more accurate final results than most direct applications of GIS techniques.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.278-281
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• 2009

KSTAR(Korea Superconducting Tokamak Advanced Research)는 고성능 플라즈마 연구를 위한 대형 연구실험 장치이다. 이러한 거대 장치에는 많은 시스템이 분산되어 연결되어 있으며 그 구조 역시 매우 복잡하여 시스템간의 인터페이스에 많은 제약과 어려움이 따른다. 이러한 복잡하고 다양한 시스템을 통합하고 여기서 발생하는 여러 종류의 데이터를 획득하기 위해서 KSTAR는 EPICS(Experimental Physics and Industrial Control System)라는 오픈소스 기반의 분산 제어용 미들웨어를 구축하였고 이를 기반으로 KSTAR 통합 제어 시스템을 개발 하였다. 2008년 KSTAR 최초 플라즈마 실험 기간 동안의 운전을 통해 EPICS 미들웨어와 EPICS channel archiver를 이용하여 다양한 24시간 연속 운전데이터를 안정적으로 저장하고 추출할 수 있음을 확인하였다. 논문에서는 시스템의 구축 방법 및 운전결과에 대해 기술하고자 한다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.5
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• pp.289-295
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• 2021

Recently, owing to the development of autonomous vehicles, research on precisely determining the position of a moving object has been actively conducted. Previous research mainly used the fusion of GNSS/IMU (Global Positioning System / Inertial Navigation System) and sensors attached to the vehicle through a Kalman filter. However, in recent years, new technologies have been used to determine the location of a moving object owing to the improvement in computing power and the advent of deep learning. Various techniques using RNN (Recurrent Neural Network), LSTM (Long Short-Term Memory), and NARX (Nonlinear Auto-Regressive eXogenous model) exist for such learning-based positioning methods. The purpose of this study is to compare the precision of existing filter-based sensor fusion technology and the NARX-based method in case of GNSS signal blockages using simulation data. When the filter-based sensor integration technology was used, an average horizontal position error of 112.8 m occurred during 60 seconds of GNSS signal outages. The same experiment was performed 100 times using the NARX. Among them, an improvement in precision was confirmed in approximately 20% of the experimental results. The horizontal position accuracy was 22.65 m, which was confirmed to be better than that of the filter-based fusion technique.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.75-86
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• 2012

Synthetic Aperture Radar(SAR) imaging system is independent of solar illumination and weather conditions; however, SAR image is difficult to interpret as compared with optical images. It has been increased interest in multi-sensor fusion technique which can improve the interpretability of $SAR^{\circ\circ}$ images by fusing the spectral information from multispectral(MS) image. In this paper, a multi-sensor fusion method based on high-frequency extraction process using Fast Fourier Transform(FFT) and outlier elimination process is proposed, which maintain the spectral content of the original MS image while retaining the spatial detail of the high-resolution SAR image. We used TerraSAR-X which is constructed on the same X-band SAR system as KOMPSAT-5 and KOMPSAT-2 MS image as the test data set to evaluate the proposed method. In order to evaluate the efficiency of the proposed method, the fusion result was compared visually and quantitatively with the result obtained using existing fusion algorithms. The evaluation results showed that the proposed image fusion method achieved successful results in the fusion of SAR and MS image compared with the existing fusion algorithms.

• Progress in Superconductivity and Cryogenics
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• v.10 no.4
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• pp.23-28
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• 2008

As a part of the plasma control system (PCS) for the first plasma campaign of KSTAR, seven sets of fast feedback control loop for the superconducting poloidal field magnet power supply (PF MPS) have been implemented. A special real-time digital communication interface has been developed for the simultaneous exchanges of the current/voltage data from the 7 sets of 12-thyristor power supplies in a 200 microsecond control cycle. Preliminary power supply tests have been performed before actual cooldown of the device. A $29mH/50m{\Omega}$ solenoid dummy has been fabricated for a series of single power supply tests. Connectivity and response speed of the plasma control system have been verified. By changing hardware cabling, this load was also used to estimate mutual inductance coupling effects of two geometrically adjacent solenoid coils on each power supply. After the cooldown was complete, each pair of the up/down symmetric PF coils has been serially connected and tested as part of the device commissioning process. Bipolar operation and longer pulse attempts have been investigated. The responses of the coils and power supplies corresponding to the plasma magnetic controls in plasma discharges are also analyzed for the future upgrades.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.9
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• pp.158-165
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• 2000

Reverse engineering is reproducing products by directly extracting geometric information from physical objects such as clay model wooden mock-up etc. The fundamental work in the reverse engineering is to acquire the geometric data for modeling the objects. This research proposes a novel method for data acquisition aiming at unmanned fast and precise measurement. This is come true by the sensor fusion with CCD camera using structured light beam and touch trigger sensor. The vision system provides global information of the objects data. In this case the number of data and position allocation for touch sensor is critical in terms of the productivity since the number of vision data is very huge. So we applied wavelet transform to reduce the number of data and to allocate the position of the touch probe. The simulated and experimental results show this method is good enough for data reduction.