• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.12
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• pp.1388-1398
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• 2012

SAR(Synthetic Aperture Radar) systems can provide images of wide coverage in day, night, and all-weather conditions. However wideband SAR systems are known to be vulnerable to interferences from other devices operating at in-band or adjacent spectrums and this may lead to image corruptions. In this paper, a SAR point target simulator is developed that provides performance analysis on image distortion caused by interferences from other devices. Interference signals are generated based on the experimental data observed from acquired SAR raw data. Simulation results include typical SAR performance measures such as spatial resolution, peak to sidelobe ratio and integrated sidelobe ratio. Finally, SAR target simulations are performed and shown to correspond to the image corruptions found in real SAR missions affected by RF interferences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4170-4175
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• 2015

The global warming has been recognized as a serious problem. To solve this problem, the country of all the world have conducted techniques such as energy saving and reduction of greenhouse gas. The 30% of total energy is being consumed by buildings domestically and BAS/BEMS are being operated for the management of building energy. But, BEMS is unsatisfactory condition to manage the energy efficiently. In this study, We investigate real application on Chamsaem elementary school as a target buildings and develop 3D Web Browser platform. The spatial information of target buildings is described with used BIM and the energy information is presented for facilities operation and electricity consumption in floor and facility. We perform the quantitative evaluation based on ISO/IEC 9126 and operate this system for two months. in result, energy decreased by about 16%. We expect that the proposed 3D Web Browser system will bring operating efficiency improvement of the current BEMS.

• Korean Journal of Optics and Photonics
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• v.31 no.6
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• pp.268-273
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• 2020

We analyze the characteristics of the coherent beam combination of lasers by monitoring the speckle pattern of the beam reflected from a scattering medium. Three collimated laser sources with high coherence are focused on a scattering target using a lens, and we then examine the speckle pattern of the returned beam in the Fourier domain. We observe that the size of the speckle pattern changes, depending on the focused-beam size or degree of spatial overlap of the three beams. Furthermore, through Fourier-domain analysis of the speckle pattern we obtain the monitoring variable to qualify the efficiency of the coherent beam combination.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.1
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• pp.17-29
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• 2024

This study was conducted to select the restoration priority of forest damage sites in Gangwon Province. We first identified the status of damaged areas. We then selected restoration evaluation indicators through a literature review. We then set weights for these indicators through expert surveys. We next acquired data that can represent these indicators and spatially mapped them. Finally, we prioritized the restoration target sites by taking the weights. The results of the study showed that disaster sensitivity and ecologicality are important criteria for selecting the restoration priority of damage sites. The analysis showed that damage sites in Doam, Jeongseon, Samcheok and Inje are in urgent need of restoration. The results of this study are significant in that they selected the restoration priority of damage sites in Gangwon Province based on the restoration priority evaluation criteria selected based on expert surveys. However, the priority restoration areas derived from the results of this study are not actually implementing restoration projects at present. Therefore, it is judged that it would be efficient in various aspects to establish the restoration priority area based on scientific analysis techniques and carry out the project for efficient implementation of the restoration project. In this study, it can be pointed out that the priority of restoration of damage sites was derived based on data from the past due to the limitation of data acquisition. However, the fact that the priority restoration area inferred based on past data has been restored over time has improved the reliability of the study by verifying the usefulness of the priority extraction technique. In the future, if the priority of damage sites is extracted by extracting the restoration target area boundary through the latest data based on the methodology applied in this study, it is considered that it will be available as a result that can be applied to the field.

• Journal of the Korean association of regional geographers
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• v.15 no.4
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• pp.510-523
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• 2009

Geodemographics(GD) can be defined as an analytical approach of socio-economic and behavioral data about people to investigate geographical patterns. GD is based on the assumptions that demographical and behavioral characteristics of people who live in the same neighborhood are similar and then the neighborhoods can be categorized with spatial classifications with the geographical classifications. Thus, this paper, in order to identify the applicability of the geographical classification of the GD, explores the concepts of the geodemographics into Seoul city areas with Korea census data sets that contain key characteristics of demographic profiles in the area. Then, this paper attempt to explain each area classification profile by using clustering techniques with Ward's and k-means statistical methods. For this as as as, this paper employs 2005 Census dataset released by Korea National Statistics Office and the neighborhood unit is based on Dong level, the smallest administrative boundary unit in Korea. After selecting and standardizing variables, several areas are categorized by the cluster techniques into 13, this paps as distinctive cluster profiles. These cluster profiles are used to cthite a short description and expand on the cluster names. Finally, the results of the classification propose a reasonable judgement for target area types which benefits for the people who make a spatial decision for their spatial problem-solving.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.1C
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• pp.26-35
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• 2006

In this paper, an automatic mobile robot system for a intelligent path planning using the detection scheme of the spatial coordinates based on stereo camera is proposed. In the proposed system, face area of a moving person is detected from a left image among the stereo image pairs by using the YCbCr color model and its center coordinates are computed by using the centroid method and then using these data, the stereo camera embedded on the mobile robot can be controlled for tracking the moving target in real-time. Moreover, using the disparity map obtained from the left and right images captured by the tracking-controlled stereo camera system and the perspective transformation between a 3-D scene and an image plane, depth information can be detected. Finally, based-on the analysis of these calculated coordinates, a mobile robot system is derived as a intelligent path planning and a estimation. From some experiments on robot driving with 240 frames of the stereo images, it is analyzed that error ratio between the calculated and measured values of the distance between the mobile robot and the objects, and relative distance between the other objects is found to be very low value of $2.19\%$ and $1.52\%$ on average, respectably.

• Spatial Information Research
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• v.22 no.2
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• pp.1-9
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• 2014

UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation in Developing Countries) and AR-CDM (Afforestation/Reforestation-Clean Development Mechanism) is currently being emerged as one of important mechanism to reduce carbon dioxide in relation to the deforestation. Discussion on North Korea as UN-REDD/AR-CDM project target continues with a view to preventing deforestation and to securing CER(certified emission reduction) for South Korea. The forests in Mt. Baekdu are degraded, deforestation is occurred, nevertheless, portion of forested area is still high, where both REDD and AR-CDM investment potential are quite high. Accordingly, this study is intended to explore a simultaneous registration potential to UNREDD/AR-CDM for Mt. Baekdu although separate registration to UN-REDD or AR-CDM has already gained worldwide recognition as a typical method in the process of GHG (Greenhouse Gas) reduction project. The results indicate that selecting UN-REDD or AR-CDM in accordance with sub-watershed forest condition could capture 53.2% more carbon dioxide than REDD alone and 21.9% more than AR-CDM alone. It is anticipated that this research output could be used as a realistic evidence to introduce carbon sequestering project in accordance with sub-watershed forest condition.

• Journal of the Korean association of regional geographers
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• v.16 no.4
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• pp.387-399
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• 2010

This study, using Fractal theory, aims to examine the meaning in the aspect of urban spatial structure by reflecting the characteristics of elements organizing the urban space and at the same time measuring the urban form quantitatively. By calculating Fractal Dimension to Cheongju as a target, it conducted comparison and analysis by dividing building and road which are internal element of a space into the whole city and urbanized area to compare and analyze validity of the theory application and the inside of an actual urban space. For the method of an analysis, it calculated Fractal Dimension by linking a digital map including the property of building and road with GIS program and using box counting. An analysis result showed that the result value of Fractal Dimension by structure and road is all high and similar. It drew a similar result value from the whole Cheongju and the urbanized area as well, but commercial and industrial area showed low result value from the partial viewpoint. However, it is correct to regard these spaces as one space because they are intimately connected with a residential area. From the general viewpoint, it could be said that Cheongju's Fractal Dimension grows in the context of a urbanized area.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.97-107
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• 2009

Experiments using real guided weapons for the development of the LADAR(Laser radar) are not practical. Therefore, we need computing environment that can simulate the 3D detections by LADAR. Such simulations require dealing with large sized data representing buildings and terrain over large area. And they also need the information of 3D target objects, for example, material and echo rate of building walls. However, currently used 3D models are mostly focused on visualization maintained as file-based formats and do not contain such semantic information. In this study, as a solution to these problems, a method to use a spatial DBMS and a 3D model suitable for LADAR simulation is suggested. The 3D models found in previous studies are developed to serve different purposes, thus, it is not easy to choose one among them which is optimized for LADAR simulation. In this study, 4 representative 3D models are first defined, each of which are tested for different performance scenarios. As a result, one model, "Body-Face", is selected as being the most suitable model for the simulation. Using this model, a test simulation is carried out.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.1
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• pp.35-41
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• 2020

3D laser scanners are an effective way to quickly acquire a large amount of data about an object. Recently, it is used in various fields such as surveying, displacement measurement, 3D data generation of objects, construction of indoor spatial information, and BIM(Building Information Model). In order to utilize the point cloud data acquired through the 3D laser scanner, it is necessary to make the data acquired from many stations through a matching process into one data with a unified coordinate system. However, analytical researches on the accuracy of point cloud data according to the registration method are insufficient. In this study, we tried to analyze the accuracy of registration method of point cloud data acquired through 3D laser scanner. The point cloud data of the study area was acquired by 3D laser scanner, the point cloud data was registered by the ICP(Iterative Closest Point) method and the shape registration method through the data processing, and the accuracy was analyzed by comparing with the total station survey results. As a result of the accuracy evaluation, the ICP and the shape registration method showed 0.002m~0.005m and 0.002m~0.009m difference with the total station performance, respectively, and each registration method showed a deviation of less than 0.01m. Each registration method showed less than 0.01m of variation in the experimental results, which satisfies the 1: 1,000 digital accuracy and it is suggested that the registration of point cloud data using ICP and shape matching can be utilized for constructing spatial information. In the future, matching of point cloud data by shape registration method will contribute to productivity improvement by reducing target installation in the process of building spatial information using 3D laser scanner.