• Journal of Korean Society for Geospatial Information Science
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• v.20 no.1
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• pp.3-12
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• 2012

It is a global trend to give attention to generating precise 3D navigation maps since eco-friendly vehicles have become a critical issue due to environmental protection and depletion of fossil fuels. To date, Mobile Mapping System (MMS) has been a efficient method to acquire the data for generating the 3D navigation maps. To achieve this goal so far in the Mobile Mapping System using the data acquisition method has been proposed to be most effective. For this study the basic RTF filter algorithm was applied to modify to fit MMS quantitative analysis derived floor 99.71%, 99.95% of the highly non-producers to maintain accuracy and high-precision 3D road could create DEM. In addition, the roads that exist within the cars, roadside tree, road cars, such as the median strips have been removed to shields it takes to get results effectively, and effective in practical applications and can be expected to improve operational efficiency is considered.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.662-671
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• 2020

It is crucial to manage and maintain the geodetic reference coordinates of GNSS continuously operating reference stations (CORSs) in consideration of their fundamental roles in geodetic control and positioning navigation infrastructure. Earthquake-induced crustal displacement directly impacts the reference coordinates, so such events should be promptly detected, and appropriate action should be made to maintain the target accuracy, including update of the geodetic coordinates. To this end, this paper deals with online schemes for the detection of persistent shifts in the coordinate time-series produced by an automatic GNSS processing system. Algorithms were implemented to test filtered results, such as hypothesis tests of the innovation sequence of a Kalman filter and a cumulative sum (CUSUM) test. The results were assessed by the time-series of coordinates of 14 CORS for two years, including the 2011 Tohoku earthquake. The results show that the global hypothesis test is practical for detecting abrupt jumps, whereas CUSUM is effective for identifying persistent shifts.

• Journal of Broadcast Engineering
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• v.4 no.2
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• pp.134-143
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• 1999

In this paper, in order to implement the IDWT(inverse discrete wavelet transform) with relatively low complexity, we propose a VLSI architecture for odd-tap linear-phase IDWT filters. By considering the symmetric property of the linear phase filter, the input is added to the one located at symmetrical position of the filter before filtering. Then. we rearrange the delay line of the filter in a U-shaped fashion. requiring no global interconnection between the components. The proposed architecture for the IDWT filter consists of delay units. operator units, adder units. and postprocessor unit. Since each units are configured regularly and interconnected locally. the proposed architecture can accommodate arbitrary linear phase IDWTs by simply adding/removing the corresponding units. The M -level IDWT can be implemented by interconnecting the proposed architecture in a cascaded or semi-recursive form. It is expected that the proposed architecture for the IDWT can be effectively employed in the related area including MPEG-4, since the proposed architecture is less complex than the conventional architectures.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.3
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• pp.13-21
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• 2011

In mobile environment supporting mobility technologies, user requirements have been increased with respect to utilization of location information. In particular, moving object DBMS has consistently posed in order to efficiently maintain traffic information related to location of vehicle which tents to tremendously change over time. Despite the fact that these sorts of researches must be taken into consideration, empirical studies on moving object in terms of map database for lbs service, spatial attribute of which is continuously changed over time, have rarely performed. Therefore, aim of this paper is to suggest efficient spatial index scheme, which is capable of supporting query processing algorithm and location of moving object over time, by developing new empirical model. As a result, we can come to the conclusion that moving object model based on multi-fixed grid index makes it possible to cut down on the number of entity for retrieving. What's more, this model enables hierarchical data to be accessed through efficient spatial filtering on large-scale lbs data and constraints in accordance with level in order to display map.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.49 no.2
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• pp.1-6
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• 2012

In recent years global climate change of hurricanes and torrential rains are going to significantly, that increase damages to property and human life. The disasters have been several claimed in every field. In future, climate changes blowing are keen to strike released to the world like in several movies. Reducing the damage of long-term weather phenomena are emerging with predicting changes in weather. In this study, it is shown how to predict the red tide phenomenon with multiple linear regression analysis and artificial neural network techniques. The red tide phenomenon causing risk could be reduced by filtering sensor data which are transmitted and forecasted in real time. It could be ubiquitous driven custom marine information service system, and forecasting techniques to use throughout the meteorological disasters to minimize damage.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.400-403
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• 2018

The VR / AR market has grown significantly due to the development of Virtual Reality and Augmented Reality, the core technologies of the Fourth Industrial Revolution. According to a report released by the Korea Science and Engineering Corporation (KISTEP), the global VR / AR market will grow to $ 105 billion by 2022. An important key to the growth of the VR / AR market is user immersion. VR is dependent on technology of hardware such as display and sensor for biometric signal recognition. In order to improve user's immersion feeling, it is important to transmit sensor data to display device more accurately and quickly. In this paper, we consider various sensor hardware dependencies of VR, and compare various correction methods and filtering methods to lower the Motion to Photon (MTP) time that user movement is fully reflected on the display using sensor devices.

• Journal of Korea Port Economic Association
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• v.27 no.4
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• pp.1-11
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• 2011

In much the same way as the US Lehman crisis of 2008-2009 severely impacted the European economy through financial market dislocation, a European banking crisis would materially impact the US economy through a generalized increase in global risk aversion. A deepening of the European crisis could very well derail the US economic recovery and have a harmful impact on the Asian economies. This kind of vicious circle could be a bad news to the shipping companies. The purpose of the study is to predict the Baltic Dry Index representing the shipping business during the period of 2012 using the ARIMA-type models. This include the ARIMA and Intervention-ARIMA models. This article introduces the four ARIMA models and six Intervention-ARIMA models. The monthly data cover the period January 2000 through October 2011. The out-of-sample forecasting performance is also calculated. Forecasting performance is measured by three summary statistics: root mean squared percent error, mean absolute percent error and mean percent error. The root mean squared percent errors, however, are somewhat higher than normally expected. This reveals that it is very difficult to predict the BDI The ARIMA-type models show that the shipping market will be bearish in 2012. These pessimistic ex-ante forecasts are supported by the Hodrick-Prescott filtering technique.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.168-172
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• 2005

An autopilot system of a ship is very important for a safe and convenient navigation, which is realized with getting an azimuth data from a gyrocompass, a magnetic compass and a GPS(Global Positioning System) compass. Magnetic compass an azimuth error is generated by a vessel magnetism material such as steels. The magnetic pole is detected by the magnetic field sensor, it does not coincide with the true north, therefore, the detected azimuth data can not but accompany error. In this paper, in order to detect the minimum change of azimuth data which generates errors of azimuth information, a search algorithm using the Kalman Filtering method is utilized. The digital electronic compass is designed with the integration algorithm using the merits of an earth's magnetic field sensor and a GPS receiver.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.255-260
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• 2006

Safety-critical navigation systems have to provide 'reliable' position solutions, i.e., they must detect and exclude measurement or system faults and estimate the uncertainty of the solution. To obtain more accurate and reliable navigation systems, various filtering methods have been employed to reduce measurement noise level, or integrate sensors, such as global navigation satellite system/inertial navigation system (GNSS/INS) integration. Recently, particle filters have attracted attention, because they can deal with nonlinear/non-Gaussian systems. In most GNSS applications, the GNSS measurement noise is assumed to follow a Gaussian distribution, but this is not true. Therefore, we have proposed a fault detection and exclusion method using particle filters assuming non-Gaussian measurement noise. The performance of our method was contrasted with that of conventional Kalman filter methods with an assumed Gaussian noise. Since the Kalman filters presume that measurement noise follows a Gaussian distribution, they used an overbounded standard deviation to represent the measurement noise distribution, and since the overbound standard deviations were too conservative compared to the actual distributions, this degraded the integrity-monitoring performance of the filters. A simulation was performed to show the improvement in performance of our proposed particle filter method by not using the sigma overbounding. The results show that our method could detect smaller measurement biases and reduced the protection level by 30% versus the Kalman filter method based on an overbound sigma, which motivates us to use an actual noise model instead of the overbounding or improve the overbounding methods.

• Journal of Biosystems Engineering
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• v.27 no.2
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• pp.151-160
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• 2002

Cow image processing technique would be useful not only for recognizing an individual but also for establishing the image database and analyzing the shape of cows. A cow (Holstein) has usually the unique speckle pattern. In this study, the individual recognition of cow was carried out using the speckle pattern and the content-based image retrieval technique. Sixty cow images of 16 heads were captured under outdoor illumination, which were complicated images due to shadow, obstacles and walking posture of cow. Sixteen images were selected as the reference image for each cow and 44 query images were used for evaluating the efficiency of individual recognition by matching to each reference image. Run-lengths and positions of runs across speckle area were calculated from 40 horizontal line profiles for ROI (region of interest) in a cow body image after 3 passes of 5$\times$5 median filtering. A similarity measure for recognizing cow individuals was calculated using Euclidean distance of normalized G-frame histogram (GH). normalized speckle run-length (BRL), normalized x and y positions (BRX, BRY) of speckle runs. This study evaluated the efficiency of individual recognition of cow using Recall(Success rate) and AVRR(Average rank of relevant images). Success rate of individual recognition was 100% when GH, BRL, BRX and BRY were used as image query indices. It was concluded that the histogram as global property and the information of speckle runs as local properties were good image features for individual recognition and the developed system of individual recognition was reliable.