• Journal of Advanced Navigation Technology
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• v.12 no.6
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• pp.659-665
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• 2008

We demonstrate experimentally that the method of Two-pupil optical scanning technique with PAL-spatial light modulator is capable of performing real-time joint transform correlation(JTC) optical system. Optical addressing is achieved by the use of a photosensitive layer of $\alpha$ - Si which controls the electric field across the liquid crystal The demonstrated technique is based on two-pupil optical heterodyne scanning. The method is independent of a spatial light modulator (SLM) in the Fourier plane. We develop the theory of the technique and evaluate a performance of the method by experimentally estimating the correlation between the target image and the reference image.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.3
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• pp.83-90
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• 2012

In this study, and taking into consideration of previous studies a trend of BIM was noticed, related to BIM software analysis and problems. Also, Geo-spatial information technology presented layered standard direction for BIM built harbor structures. Thoughts of this study, existing of two-dimensions and BIM problems based on architecture needs for applications were identified. Also, harbor structures targeting civil-BIM layer of technology-based GIS projects, and Busan International Ferry Terminal to target existing BIM comparison with harbors in the field based on GIS civil engineering-BIM standardization and direction of application could be presented.

• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.149-153
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• 2015

A digital micro-mirror device (DMD) has the potential to modulate an incident wave with high speed, and the application for holographic display has been studied by many researchers. However, the quality of reconstructed image isn't good in comparison with that from a gray-scale amplitude-only hologram since it is a binary amplitude-only spatial light modulator (SLM). In this paper, we suggest a method generating a set of binary holograms to improve the quality of the reconstructed image. Here, we are concerned with the case for which the object plane is positioned at the Fourier domain of the plane of the SLM. In this case, any point in the Fourier plane is related to all points in the hologram. So there is a chance to generate a set of binary holograms illuminated by incident wave with constant optical power. Moreover, we find an interesting fact that the quality of reconstructed image is improved when the spatial frequency bandwidth of the binary hologram is limited. Therefore, we propose an iterative segmentation algorithm generating a set of binary holograms that are designed to be illuminated by the wave with constant optical power. The feasibility of our method is experimentally confirmed with a DMD.

• Journal of the Korea Society of Computer and Information
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• v.24 no.7
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• pp.109-116
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• 2019

In this study, a GIS-based park safety assessment index was developed to enable objective park vulnerability assessment through data-based GIS analysis, a safety assessment was conducted by selecting a target site where various parks are operated and applying the park safety assessment index. In addition, a facility management system was developed for efficient management of the park safety assessment to update the park safety and provide a foothold for indirect PPGIS. In the case of the assessment index of the safety rating of the park, it was possible to conclude that the accurate quantitative performance was given to the calculation of the safety grade of the park based on the fact that the facilities are different depending on the environment and the size of the park. In addition, the marking the safety grade of parks, as well as the function to show the safety facilities of parks, a common living area for citizens, the management system is expected to have an impact on promoting the use of parks. In the future, in functions such as reporting of facility failures and verifying civil information are implemented by applying civic group participation programs and crowd-sourcing technologies, it is believed that all facilities as well as parks managed by the local government can be managed more efficiently.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.89-93
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• 2013

This paper is estimating a target direction of arrival with incident to receiver in spatial. This paper presented covariance using constraint matrix to correlation interference signal cancellation in multi input multi output array antennas system. we proposed a target direction of arrival estimation algorithm using cost function and minimum variance method. Through simulation, we were analysis a performance to compare general SPT-LCMV algorithm and proposal algorithm. We showed that proposal algorithm improve more target estimation than general SPT-LCMV algorithm in direction of arrival.

• Journal of Korea Multimedia Society
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• v.24 no.5
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• pp.659-666
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• 2021

With the continuous development of deep learning, human behavior recognition algorithms have achieved good results. However, in a multi-person recognition environment, the complex behavior environment poses a great challenge to the efficiency of recognition. To this end, this paper proposes a multi-person pose estimation model. First of all, the human detectors in the top-down framework mostly use the two-stage target detection model, which runs slow down. The single-stage YOLOv3 target detection model is used to effectively improve the running speed and the generalization of the model. Depth separable convolution, which further improves the speed of target detection and improves the model's ability to extract target proposed regions; Secondly, based on the feature pyramid network combined with context semantic information in the pose estimation model, the OHEM algorithm is used to solve difficult key point detection problems, and the accuracy of multi-person pose estimation is improved; Finally, the Euclidean distance is used to calculate the spatial distance between key points, to determine the similarity of postures in the frame, and to eliminate redundant postures.

• The Journal of the Acoustical Society of Korea
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• v.23 no.4
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• pp.288-295
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• 2004

Detection and localization of a slow and quiet target in shallow water environments is a challenging problem for which it is well known that snapshot is deficient because of a fast and strong interferer. This paper presents waveguide interference filtering technique that mitigate strong interferer problems in adaptive matched field processing. MCM (multiple constraint method) based on NDC (null direction constraint) has been proposed for new spatial interferer filter. MCM-NDC using replica force a interferer component to be filtered through CSDM (cross-spectral density matrix). This filtering have an effect on sidelobe reduction and restoring of signal gain of a quiet target. This technique was applied to a simulation on Pekeris waveguide and vertical array data from MAPLE03 (matched acoustic properties and localization experiment) in the East Sea and was shown to improve SBNR (signal-to-background-and-noise ratio) over the standard MVDR (minimum-variance distortionless response) and NSP (null space projection) technique.

• Spatial Information Research
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• v.23 no.3
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• pp.91-100
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• 2015

We developed a micro UAV based rapid mapping system that provides geospatial information of target areas in a rapid and automatic way. Users can operate the system easily although they are inexperienced in UAV operation and photogrammetric processes. For the aerial data acquisition, we constructed a micro UAV system mounted with a digital camera, a GPS/IMU, and a control board for the sensor integration and synchronization. We also developed a flight planning software and data processing software for the generation of geo-spatial information. The processing software operates automatically with a high speed to perform data quality control, image matching, georeferencing, and orthoimage generation. With the system, we have generated individual ortho-images within 30 minutes from 57 images of 3cm resolution acquired from a target area of $400m{\times}300m$.

• Journal of the Ergonomics Society of Korea
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• v.31 no.6
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• pp.705-713
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• 2012

Objective: The aim of this study is to predict human visual target search using ACT-R cognitive architecture in real scene images. Background: Human uses both the method of bottom-up and top-down process at the same time using characteristics of image itself and knowledge about images. Modeling of human visual search also needs to include both processes. Method: In this study, visual target object search performance in real scene images was analyzed comparing experimental data and result of ACT-R model. 10 students participated in this experiment and the model was simulated ten times. This experiment was conducted in two conditions, indoor images and outdoor images. The ACT-R model considering the first saccade region through calculating the saliency map and spatial layout was established. Proposed model in this study used the guide of visual search and adopted visual search strategies according to the guide. Results: In the analysis results, no significant difference on performance time between model prediction and empirical data was found. Conclusion: The proposed ACT-R model is able to predict the human visual search process in real scene images using salience map and spatial layout. Application: This study is useful in conducting model-based evaluation in visual search, particularly in real images. Also, this study is able to adopt in diverse image processing program such as helper of the visually impaired.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.4
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• pp.77-87
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• 2012

Discussion on North Korea as UN-REDD (Reduced Emissions from Deforestation and Degradation in developing countries) project target continues with a view to preventing deforestation and to securing CER(certified emission reduction) for South Korea. However, due to North Korea's political shutdown, it is hard to acquire information required for the REDD project registration. This research intends to acquire objective data using satellite images in the Mt. Geumgang. More than 20% of entire forested area were disappeared during the past two decades mainly due to conversion into agricultural farming land. Further, it is expected that persistent deforestation will go on. The reduction potential of the carbon emission is estimated as approximately 617,000 tCO2/year~663.000 tCO2/year. Thus, Mt. Geumgang is considered as realistic REDD target, which is attractive to South Korea, given that the obligation to reduce greenhouse gas emission is likely to be imposed upon the country. Further, political and social benefits due to reduced military conflict make Mt. Geumgang as UN-REDD project target invaluable.