• Title/Summary/Keyword: 한국 지형학회

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Contamination Source Assessment of Groundwater Nitrate in a Complex Terrain (복잡한 지형에서 발생하는 지하수의 질산태 질소 오염원 평가)

  • Han, Gwang-Hyun
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.1
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    • pp.14-20
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    • 2009
  • Classification of land uses and analysis of nitrogen isotope fractionation in groundwater nitrate were carried out to examine its contamination sources in Jeju province. ${\delta}^{15}N$ values of urea (hydrolyzed with urease), ammonium sulfate, compost, water from septic tank were -1.7, -5.8, +14.1, and +24.0‰, respectively. Urea, when it was directly distillated, showed -16.5‰. Based on these ${\delta}^{15}N$ values, sources of nitrate could be classified as originated from chemical fertilizers with ${\delta}^{15}N$ values below +5‰ and as from animal manure or municipal waste with ${\delta}^{15}N$ values over +10‰. Results of ${\delta}^{15}N$ analysis of 33 wells showed that most wells had the chemical fertilizers as their dominant contamination source. However, some wells were contaminated by other sources: animal wastes or municipal wastes. Some wells were also contaminated by the combined sources of nitrate. It was also demonstrated that ${\delta}^{15}N$ analysis could be a useful tool even in the case where no apparent contamination source is found.

Regional-Scale Evaluation of Groundwater Susceptibility to Nitrate Contamination Based on Soil Survey Information (토양정보를 이용한 광역 지하수의 질산태 질소 오염 민감도 분포 분석)

  • Han, Gwang-Hyun
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.1
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    • pp.37-45
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    • 2009
  • Susceptibility assessment of groundwater contamination is a useful tool for many aspects of regional and local groundwater resources planning and management. It can be used to direct regulatory, monitoring, educational, and policy-making efforts to highly vulnerable areas. In this study, a semi process-based was proposed to evaluate relative susceptibilities to groundwater contamination by nitrate on a regional scale. Numerical simulation based on data from each soil series was done to model water flow within soil profiles that were related to groundwater contamination by nitrate. Relative vulnerability indices for each soil series were produced by manipulation of amount of leaching flux, amount of average water storage in a soil profile, and amount of average water storage change. These indices were designed to convey the trend of leaching flux and to maximize spatial resolution. The resulting vulnerability distribution map was used to locate highly vulnerable sites easily with an appropriate grouping the indices, and was then compared with those from groundwater nitrate concentrations monitored. An excellent agreement was obtained across nitrate concentrations from the highly vulnerable regions and those from the low to stable regions.

Decision-Making System of UAV for ISR Mission Level Autonomy (감시정찰 임무 자율화를 위한 무인기의 의사결정 시스템)

  • Uhm, Taewon;Lee, Jang-Woo;Kim, Gyeong-Tae;Yang, Seung-Gu;Kim, Joo-Young;Kim, Jae-Kyung;Kim, Seungkeun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.10
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    • pp.829-839
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    • 2021
  • Autonomous system for UAVs has a capability to decide an appropriate current action to achieve the goal based on the ultimate mission goal, context of mission, and the current state of the UAV. We propose a decision-making system that has an ability to operate ISR mission autonomously under the realistic limitation such as low altitude operation with high risk of terrain collision, a set of way points without change of visit sequence not allowed, and position uncertainties of the objects for the mission. The proposed decision-making system is loaded to a Hardware-In-the-loop Simulation environment, then tested and verified using three representative scenarios with a realistic mission environment. The flight trajectories of the UAV and selected actions via the proposed decision-making system are presented as the simulation results with discussion.

Multidisciplinary Research for Types and Storytelling Strategies of Science Technology YouTube Channel : focused on Activity-centered Type Video Channel (과학기술 유튜브 채널의 유형과 스토리텔링 전략에 대한 다학제적 연구 : 활동형 채널을 중심으로)

  • Kim, Hye Yung;Yoo, Dong Hwan
    • Korea Science and Art Forum
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    • v.37 no.3
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    • pp.113-123
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    • 2019
  • In line with policy support and demand, mobile videos about science and technology have growth potential. For activation of domestic mobile video contents about science and technology, this article aims to analysis current global leading contents and draw implications for benchmarking. Therefore, this paper attempted to analyzed types and storytelling strategy of Science and technology channels on YouTube, which has the most influence among the mobile video media. The results are as follows. Fist, the YouTube contents about science technology are categorized into three types, activity-, explain-, review-centered type. Second, activity type channels are classified into 4 sub-types. Third, The core storytelling strategy of activity type channels is a combination of familiarity and unfamiliarity to deal with everyday material through specialized scientific and technological methods. Based on the results of this research, we expect to plan and produce global killer contents.

Design of INS/GNSS/TRN Integrated Navigation Considering Compensation of Barometer Error (기압고도계 오차 보상을 고려한 INS/GNSS/TRN 통합항법 설계)

  • Lee, Jungshin;Sung, Changky;Park, Byungsu;Lee, Hyungsub
    • Journal of the Korea Institute of Military Science and Technology
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    • v.22 no.2
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    • pp.197-206
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    • 2019
  • Safe aircraft requires highly reliable navigation information. The traditionally used inertial navigation system (INS) often displays faulty location information due to its innate errors. To overcome this, the INS/GNSS or INS/TRN integrated navigation can be used. However, GNSS is vulnerable to jamming and spoofing, while TRN can be degraded in the flat and repetitive terrains. In this paper, to improve the performance and ensure the high reliability of the navigation system, the INS/GNSS/TRN integrated navigation based on federated filter is designed. Master filter of the integrated navigation uses the estimates and covariances of two local filters - INS/GNSS and INS/TRN integrated filters. The local filters are designed with the EKF that is feedforward type and composed of the 17st state variables. And the INS/GNSS integrated navigation includes the barometer error compensation method. Finally, the proposed INS/GNSS/TRN integrated navigation is verified by vehicle and captive flight tests.

Risk Factors Analysis and Quantitative Risk Assessment Model for Plant Construction Project (플랜트 건설 리스크 분석 및 리스크 정량화 모델 개발에 관한 연구)

  • Ahn, Sung-Jin;Kim, Tae-Hui;Nam, Kyung-Yong;Kim, Ji-Myong
    • Journal of the Korea Institute of Building Construction
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    • v.19 no.1
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    • pp.77-86
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    • 2019
  • Due to the increasing demand for and complexity of plant construction projects, unpredictable risk factors are on the consequent increase. For that reason, the quantitative risk analysis is being called for, in order for the development of a risk assessment model using risk indicators for the plant construction projects. This study used the claim payout data collected at a global insurance company to reflect the actual financial losses in plant construction projects as dependent variables in the risk assessment model. In terms of independent variables, the geographic information, i. e., landform, and the construction information including test-run, schedule rate, total cost and duration are adopted. In addition, this study suggests that the regression model containing such independent variables that are statistically significant can be applied to as a foundational guideline for the plant construction project risk analysis during the phase of construction and commissioning.

LOD(Level of Detail) Model for Utilization of Indoor Spatial Data (실내 공간정보 활용을 위한 세밀도 모델)

  • Kang, Hye Young;Nam, Sang Kwan;Hwang, Jung Rae;Lee, Ji Yeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.6
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    • pp.545-554
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    • 2018
  • As the map paradigm shifts from analog to digital, the LOD (Level Of Detail) of spatial information needs to be redefined. In this study, we propose 4- dimensional indoor LOD model which can be used in digital map environment. For this purpose, the limitation of the previous research is derived through study of related works, and based on this, four different LODs are defined such PLOD (Position accuracy LOD) based on position accuracy, GLOD (Geometric LOD) based on shape representation, CLOD (Complete LOD) based on generalization, and SLOD (Semantic LOD) based on theme accuracy. In addition, we describe the relationships among the four different LODs, and explain how to express the indoor LOD using the four different LODs and show examples. In the future, the case studies of indoor LOD adoption for various indoor services and the study of method for applying CLOD and SLOD to each feature should be performed to verify the feasibility and validity of proposed indoor LOD.

Classification of 3D Road Objects Using Machine Learning (머신러닝을 이용한 3차원 도로객체의 분류)

  • Hong, Song Pyo;Kim, Eui Myoung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.6
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    • pp.535-544
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    • 2018
  • Autonomous driving can be limited by only using sensors if the sensor is blocked by sudden changes in surrounding environments or large features such as heavy vehicles. In order to overcome the limitations, the precise road-map has been used additionally. This study was conducted to segment and classify road objects using 3D point cloud data acquired by terrestrial mobile mapping system provided by National Geographic Information Institute. For this study, the original 3D point cloud data were pre-processed and a filtering technique was selected to separate the ground and non-ground points. In addition, the road objects corresponding to the lanes, the street lights, the safety fences were initially segmented, and then the objects were classified using the support vector machine which is a kind of machine learning. For the training data for supervised classification, only the geometric elements and the height information using the eigenvalues extracted from the road objects were used. The overall accuracy of the classification results was 87% and the kappa coefficient was 0.795. It is expected that classification accuracy will be increased if various classification items are added not only geometric elements for classifying road objects in the future.

GCP Chip Automatic Extraction of Satellite Imagery Using Interest Point in North Korea (특징점 추출기법을 이용한 접근불능지역의 위성영상 GCP 칩 자동추출)

  • Lee, Kye Dong;Yoon, Jong Seong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.4
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    • pp.211-218
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    • 2019
  • The Ministry of Land, Infrastructure and Transport is planning to launch CAS-500 (Compact Advanced Satellite 500) 1 and 2 in 2019 and 2020. Satellite image information collected through CAS-500 can be used in various fields such as global environmental monitoring, topographic map production, analysis for disaster prevention. In order to utilize in various fields like this, it is important to get the location accuracy of the satellite image. In order to establish the precise geometry of the satellite image, it is necessary to establish a precise sensor model using the GCP (Ground Control Point). In order to utilize various fields, step - by - step automation for orthoimage construction is required. To do this, a database of satellite image GCP chip should be structured systematically. Therefore, in this study, we will analyze various techniques for automatic GCP extraction for precise geometry of satellite images.

Separation Device Development and Flight Test for Marine Recovery of Scientific Balloon (과학기구 기낭의 해상 회수를 위한 분리장치 개발 및 비행시험)

  • Shim, Gyujin;Kang, Jungpyo;Kim, Hweeho;Yee, Kwanjung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.47 no.1
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    • pp.49-58
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    • 2019
  • The Scientific balloon is a flight system that could recover an entire platform at the end of the mission. The recovery takes place mainly in low-density populated areas, taking into account for the possible damage to the human life and public safety. In Republic of Korea, on the other hand, marine recovery should be considered due to the dense mountainous terrain and restrictions of the peninsula. In this operating environment, the envelope must be recovered because of severe marine pollution that may occur after the splashdown. Therefore, in this study, the separation device that consists of a location tracker and the waterproof system were developed. The device includes data transmission/reception, separation, and waterproof systems which are manufactured considering the environmental condition of the Korea. The performance of the device and the trajectory of the envelope were verified by conducting a separation test of a 20km platform at a target altitude and the recovery of the zero-pressure balloon.