• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.577-589
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• 2021

Drone mapping systems can be applied to many fields such as disaster damage investigation, environmental monitoring, and construction process monitoring. To integrate individual sensors attached to a drone, it was essential to undergo complicated procedures including time synchronization. Recently, a variety of composite sensors are released which consist of visual sensors and GPS/INS. Composite sensors integrate multi-sensory data internally, and they provide geotagged image files to users. Therefore, to use composite sensors in drone mapping systems, mapping accuracies from composite sensors should be examined. In this study, we analyzed the mapping accuracies of a composite sensor, focusing on the data acquisition area and pre-calibration effect. In the first experiment, we analyzed how mapping accuracy varies with the number of ground control points. When 2 GCPs were used for mapping, the total RMSE has been reduced by 40 cm from more than 1 m to about 60 cm. In the second experiment, we assessed mapping accuracies based on whether pre-calibration is conducted or not. Using a few ground control points showed the pre-calibration does not affect mapping accuracies. The formation of weak geometry of the image sequences has resulted that pre-calibration can be essential to decrease possible mapping errors. In the absence of ground control points, pre-calibration also can improve mapping errors. Based on this study, we expect future drone mapping systems using composite sensors will contribute to streamlining a survey and calibration process depending on the data acquisition circumstances.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.5
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• pp.331-341
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• 2019

With the popularity of sensor-rich environments, smartphones have become one of the major platforms for obtaining and sharing information. Since it is difficult to utilize GNSS (Global Navigation Satellite System) inside the area with many buildings, the localization of smartphone in this case is considered as a challenging task. To resolve problem of localization using smartphone a four step image-based localization method and procedure is proposed. To improve the localization accuracy of smartphone datasets, MMS (Mobile Mapping System) and Google Street View were utilized. In our approach first, the searching for candidate matching image is performed by the query image of smartphone's using GNSS observation. Second, the SURF (Speed-Up Robust Features) image matching between the smartphone image and reference dataset is done and the wrong matching points are eliminated. Third, the geometric transformation is performed using the matching points with 2D affine transformation. Finally, the smartphone location and attitude estimation are done by PnP (Perspective-n-Point) algorithm. The location of smartphone GNSS observation is improved from the original 10.204m to a mean error of 3.575m. The attitude estimation is lower than 25 degrees from the 92.4% of the adjsuted images with an average of 5.1973 degrees.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.1
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• pp.113-123
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• 2001

The purpose of this study is to help out the settlement of the Green Map in Korea, and to suggest how to map, and help community people and environmental planner systematically take care of their own towns. This study is also to introduce the green mapping and its usefulness, based on the Green Map Movement, which originated from Net York City and has been expanding through the World. Environmental elements shown on the Green map vary between countries and for the Seocho-Gu Green Map, we have decided to indicate the places that we are proud of, and dishonored of. Especially, this paper is focused on finding the hidden environmental resources in our daily lives. Seocho-Gu, one of 25 self-governmental resources. Since the citizens and government officials are open-minded in their environments, it is a suitable area to start the first Green Map in Korea. As a method of locating the environmental resources, the "Foot Sensing Method" by which residents directly research, is the main difference from typical maps by the "Remote Sensing" which focused on the variety participation of the residents such as questionnaires, investigation with youth volunteers, users interviews which may be more meaningful than the Green Map itself. The purpose of application plan is to preserve the environmental resources through the smooth feedback with the residents. Thus, it must be acted as a opening window linking them with the local circumstances. In line with this, this study proposed the trial-version Web Green Map and Green tour plan. Recently, a need for an environmental map has been reflected in the environmental policies of Seoul Metropolitan City, and it is in place now. If environmental experts of different disciplines use the Green Map for landscape architecture, design, and city planning, it will help them make a better understanding of the needs of the community and to practice the user-centered design. Eventually, the Seocho-Gu Green Map will help its residents, tourists, government, and environmental planners continue establishing the healthy city environments. It is expected that the green map will be employed as a useful method for establishing healthy city and town through right way of use and contents.of use and contents.

• Journal of the Korea Society for Simulation
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• v.14 no.2
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• pp.15-24
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• 2005

The goal of a distributed simulation such as battle field simulation is to combine all kinds of simulations in the same synthetic environment and to make people interact at the same time. It is a key issue to share the same synthetic environment among simulations. To support reusability and affordability in the modeling and simulation area, DMSO(Defense Modeling and Simulation Office) of USA developed concepts such as HLA(High Level Architecture) and SEDRIS (Synthetic Environmental Data Representation and Interchange Specification). In the industrial simulation area, the digital manufacturing is the main stream. To reduce cost and to reuse simulation environment, the standardization becomes the focus of digital manufacturing. This study proposes to use SEDRIS to improve interoperability of manufacturing data. The simulation data of DELMIA, which is a leading commercial digital manufacturing solution, is mapped and translated into the SEDRIS transmittal format. Mapping of the manufacturing simulation data and the synthetic environment are implemented and verified through experiments.

• Journal of the Korean Society of Safety
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• v.22 no.3 s.81
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• pp.74-80
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• 2007

In this study, a documentary survey, face mapping, and stability analysis were performed on the collapsed colluvial soil slope. The purpose of this paper is to identify the cause of slope failure and determine slope stability for similar areas. Boring samples were extracted from the slump and laboratory tests were performed to find out the cause of slope failure. In addition, the limit equilibrium method was used in order to determine the stability of the slope. As a result of this investigation and the analysis of data, the type of collapse and cause of slope failure have been shown to have a strong correlation with the natural geographical and geological features which make up the collapse profile of the study area. These results will help to develop guidelines for formulating countermeasure methods.

• The Journal of Korea Robotics Society
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• v.16 no.2
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• pp.122-129
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• 2021

For the Simultaneous Localization and Mapping (SLAM) problem, a different path results in different SLAM results. Usually, SLAM follows a trail of input data. Active SLAM, which determines where to sense for the next step, can suggest a better path for a better SLAM result during the data acquisition step. In this paper, we will use reinforcement learning to find where to perceive. By assigning entire target area coverage to a goal and uncertainty as a negative reward, the reinforcement learning network finds an optimal path to minimize trajectory uncertainty and maximize map coverage. However, most active SLAM researches are performed in indoor or aerial environments where robots can move in every direction. In the urban environment, vehicles only can move following road structure and traffic rules. Graph structure can efficiently express road environment, considering crossroads and streets as nodes and edges, respectively. In this paper, we propose a novel method to find optimal SLAM path using graph structure and reinforcement learning technique.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.241-243
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• 2018

In this paper, in Simultaneous localization and mapping (SLAM), the robot acquire its map of environment while simultaneously localizing itself relative to the map. Cloud based SLAM, allows us to optimizing resource and data sharing like map of the environment, which allows us, as one of shared available online map. Doing so, unless we add or remove significant change in our environment, the essence of rebuilding new environmental map are omitted to new mobile robot added to the environment. As result, the requirement of additional sensor are curtailed.

• Proceedings of the KSRS Conference
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• v.2
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• pp.840-843
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• 2006

The aim of this study was to detect landslide using satellite image and apply the landslide to probabilistic landslide-susceptibility mapping at Gangneung area, Korea using a Geographic Information System (GIS). Landslide locations were identified by change detection technique of KOMSAT-1 (Korea Multipurpose Satellite) EOC (Electro Optical Camera) images and checked in field. For landslide-susceptibility mapping, maps of the topography, geology, soil, forest, lineaments, and land cover were constructed from the spatial data sets. Then, the sixteen factors that influence landslide occurrence were extracted from the database. Using the factors and detected landslide, the relationships were calculated using frequency ratio, one of the probabilistic model. Then, landslide-susceptibility map was drawn using the frequency ration and finally, the map was verified by comparing with existing landslide locations. As the verification result, the prediction accuracy showed 86.76%. The landslide-susceptibility map can be used to reduce hazards associated with landslides and to land cover planning.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.4
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• pp.54-65
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• 2000

The purpose of this paper is to examine the concept, general framework, planning process of bioregion, and bioregional impacts on landscape planning of future and to discuss the application possibility of landscape planning. Bioregionalism is defined in the course of following: knowing the land, learning the lore, developing the potential, liberating the self. Bioregional paradigm was composed of policy system insisted on diversity and decentralization based on region and community, sustainable economy structure focused on conservation and stability, and society structure through cooperation with common consciousness in the community. A general bioregional framework was organized to be able to achieve a sustainable future with interaction for humans being, other living things, and important earth life system. Bioregional mapping should be able to explain three important aspects about how localised and sustainable cultures would exist: to define the external boundaries, to describe forces of energy, and give a hint for th productive capability. In conclusion, according to the result of reviewing the total environmental planning, bioregional paradigm, examples of projects, technique of bioregional mapping, and actions of Nongovernmental Organizations(NGOs). this study is helpful to show an applicability of bioregional planning theory in Korea

• Korean Journal of Remote Sensing
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• v.20 no.5
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• pp.329-335
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• 2004

Biotop map can be utilized for nature conservation and assessment of environmental impact for human activities in urban area. High resolution satellite images such as IKONOS and KOMPSAT1-EOC were interpreted to classify land use, hydrology, impermeable pavement ratio and vegetation for biotop mapping. Wildlife habitat map and detailed vegetation map obtained from former study results were used as ground truth data. Vegetation was investigated directly for the area where the detailed vegetation map is not available. All these maps were combined and the boundaries were delineated to produce the biotop map. Within the boundary, the characteristics of each polygon were identified, and named. This study investigates the possibility of biotop mapping using high resolution satellite remote sensing data together with field data with the goal of contributing to nature conservation in urban area.