• Title/Summary/Keyword: Earth system model

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Development of KITSAT-3 High Resolution CCD Camera System (우리별 3호 탑재 고해상도 CCD 카메라시스템 개발)

  • 유상근;장현석;이흥규;최순달
    • Korean Journal of Remote Sensing
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    • v.12 no.2
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    • pp.97-110
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    • 1996
  • In this paper, we describe the structure, function, and the operation method of the high resolution CCD camera system on the KITSAT-3, which will be launched in 1998. We have developed the camera system with the University of Stellenbosch in the Republic of South Africa. Currently we are doing the environmental test for the engineering model of the camera system. The main purposes of the system are the technology acquisition and operation test. The around resolution of the system is 15 m at the 800 Km earth orbit.

Effects of Atmospheric Stability and Surface Temperature on Microscale Local Airflow in a Hydrological Suburban Area (대기 안정도와 지표면 온도가 미세규모 국지 흐름에 미치는 영향: 수문지역을 대상으로)

  • Park, Soo-Jin;Kim, Do-Yong;Kim, Jae-Jin
    • Atmosphere
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    • v.23 no.1
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    • pp.13-21
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    • 2013
  • In this study, the effects of atmospheric stability and surface temperature on the microscale local airflow are investigated in a hydrological suburban area using a computational fluid dynamics (CFD) model. The model domain includes the river and industrial complex for analyzing the effect of water system and topography on local airflow. The surface boundary condition is constructed using a geographic information system (GIS) data in order to more accurately build topography and buildings. In the control experiment, it is shown that the topography and buildings mainly determine the microscale airflow (wind speed and wind direction). The sensitivity experiments of atmospheric stability (neutral, stable, and unstable conditions) represent the slight changes in wind speed with the increase in vertical temperature gradient. The differential heating of ground and water surfaces influences on the local meteorological factors such as air temperature, heat flow, and airflow. These results consequentially suggest that the meteorological impact assessment is accompanied by the changes of background land and atmospheric conditions. It is also demonstrated that the numerical experiments with very high spatial resolution can be useful for understanding microscale local meteorology.

A Curriculum Development on the Disaster Management (재해관리에 대한 교육과정 개발)

  • 강윤숙;이옥철;이계복
    • Journal of Korean Academy of Nursing
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    • v.28 no.1
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    • pp.210-220
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    • 1998
  • The various and serious types of disaster occur everyday and everywhere on the earth. There is no doubt that it is very timely to discuss about the effectiveness and preparedness of disaster. The purpose of this study is to develop a curriculum on the disaster management through reviewing disaster concepts and the disaster management system. For the empirical relevance of the study, researchers participated in a couple or more disaster training program, reviewed references, and consulted to the experts working on action parts in the area. As a result, the 'Integrated Disaster Management System Model (IDMSM)' was designed, in which four dimensions were explained. Then the 'Disaster Curriculum Model (DCM)' was explored with its theoretical framework based on the system model. The developed curriculum is composed of four levels ; the introductory course, the fundamental course, the advanced course, and the expert course. From this DCM, basically the course-outlines of two subjects in the introductory course, 18 subjects in the fundamental course (5 of direct services. 13 of indirect services) were developed. Also each course-outline was explored by its course objective, learning objectives, contents, and its length. Finally to make the most of the results, suggestions are proposed. The governmental considerations on the policy should support the systematic and integrated educational program to practice, appointing 「Disaster School」 or 「Disaster Training Center」 of relevance and accountabilities. The further study should explore the higher levels of the DCM through interdisciplinary efforts, and develop the text aterials. ilities. The further study should explore the higher levels of the DCM through interdisciplinary efforts, and develop the text materials.

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Operation Model for Forest-UAV for Detection of Forest Disease (산림병해충 검출을 위한 산림무인항공기 운영 모델)

  • Byun, Sangwoo;Kang, Yunhee
    • Journal of Platform Technology
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    • v.8 no.1
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    • pp.3-9
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    • 2020
  • In Korea, 63% of the nation's land is made up of forests, and the average temperature of the earth has been increasing. Forest service has been operating a proactive control system for preventing the spread of forest pests such as Pine wilt disease. but there were some hurdles in timely control due to weather, topography and manpower management difficulties. In this paper, we propose a model for building fast, accurate and efficient control system by categorizing the damage and dead wood automatically based on the images acquired using small unmanned aerial vehicles based on information and communication technology. In particular, the proposed model establishes an effective response system for government affairs through cooperation in the private sector. It can also create new jobs in the unmanned aerial vehicle business and service industries.

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The Failure Analysis of Paralleled Solar Array Regulator for Satellite Power System in Low Earth Orbit

  • Jang, Sung-Soo;Kim, Sung-Hoon;Lee, Sang-Ryool;Choi, Jae-Ho
    • Journal of Astronomy and Space Sciences
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    • v.28 no.2
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    • pp.133-141
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    • 2011
  • A satellite power system should generate and supply sufficient electric power to perform the satellite mission successfully during the satellite mission period, and it should be developed to be strong to the failure caused by the severe space environment. A satellite power system must have a high reliability with respect to failure. Since it cannot be repaired after launching, different from a ground system, the failures that may happen in space as well as the effect of the failures on the system should be considered in advance. However, it is difficult to use all the hardware to test the performance of the satellite power system to be developed in order to consider the failure mechanism of the electrical power system. Therefore, it is necessary to develop an accurate model for the main components of a power system and, based on that, to develop an accurate model for the entire power system. Through the power system modeling, the overall effect of failure on the main components of the power system can be considered and the protective design can be devised against the failure. In this study, to analyze the failure mode of the power system and the effects of the failure on the power system, we carried out modeling of the main power system components including the solar array regulator, and constituted the entire power system based on the modeling. Additionally, we investigated the effects of representative failures in the solar array regulator on the power system using the power system model.

Review of Thermodynamic Sorption Model for Radionuclides on Bentonite Clay (벤토나이트와 방사성 핵종의 열역학적 수착 모델 연구)

  • Jeonghwan Hwang;Jung-Woo Kim;Weon Shik Han;Won Woo Yoon;Jiyong Lee;Seonggyu Choi
    • Economic and Environmental Geology
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    • v.56 no.5
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    • pp.515-532
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    • 2023
  • Bentonite, predominantly consists of expandable clay minerals, is considered to be the suitable buffering material in high-level radioactive waste disposal repository due to its large swelling property and low permeability. Additionally, the bentonite has large cation exchange capacity and specific surface area, and thus, it effectively retards the transport of leaked radionuclides to surrounding environments. This study aims to review the thermodynamic sorption models for four radionuclides (U, Am, Se, and Eu) and eight bentonites. Then, the thermodynamic sorption models and optimized sorption parameters were precisely analyzed by considering the experimental conditions in previous study. Here, the optimized sorption parameters showed that thermodynamic sorption models were related to experimental conditions such as types and concentrations of radionuclides, ionic strength, major competing cation, temperature, solid-to-liquid ratio, carbonate species, and mineralogical properties of bentonite. These results implied that the thermodynamic sorption models suggested by the optimization at specific experimental conditions had large uncertainty for application to various environmental conditions.

Calculation of Surface Broadband Emissivity by Multiple Linear Regression Model (다중선형회귀모형에 의한 지표면 광대역 방출율 산출)

  • Jo, Eun-Su;Lee, Kyu-Tae;Jung, Hyun-Seok;Kim, Bu-Yo;Zo, Il-Sung
    • Journal of the Korean earth science society
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    • v.38 no.4
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    • pp.269-282
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    • 2017
  • In this study, the surface broadband emissivity ($3.0-14.0{\mu}m$) was calculated using the multiple linear regression model with narrow bands (channels 29, 30, and 31) emissivity data of the Moderate Resolution Imaging Spectroradiometer (MODIS) on Earth Observing System Terra satellite. The 307 types of spectral emissivity data (123 soil types, 32 vegetation types, 19 types of water bodies, 43 manmade materials, and 90 rock) with MODIS University of California Santa Barbara emissivity library and Advanced Spaceborne Thermal Emission & Reflection Radiometer spectral library were used as the spectral emissivity data for the derivation and verification of the multiple linear regression model. The derived determination coefficient ($R^2$) of multiple linear regression model had a high value of 0.95 (p<0.001) and the root mean square error between these model calculated and theoretical broadband emissivities was 0.0070. The surface broadband emissivity from our multiple linear regression model was comparable with that by Wang et al. (2005). The root mean square error between surface broadband emissivities calculated by models in this study and by Wang et al. (2005) during January was 0.0054 in Asia, Africa, and Oceania regions. The minimum and maximum differences of surface broadband emissivities between two model results were 0.0027 and 0.0067 respectively. The similar statistical results were also derived for August. The surface broadband emissivities by our multiple linear regression model could thus be acceptable. However, the various regression models according to different land covers need be applied for the more accurate calculation of the surface broadband emissivities.

Accuracy Analysis of GNSS-derived Orthometric Heights on the Leveling Loop Disconnected Area

  • Jung, Sung Chae;Kwon, Jay Hyoun;Lee, Jisun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.1
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    • pp.1-8
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    • 2018
  • To compensate for the shortcomings of spirit leveling, research on the determination of GNSS (Global Navigation Satellite System)-derived orthometric height has been actively carried out. However, most analyses were primarily performed inland. In this study, the influences of the arrangement of control points, observation duration, and geoid model on the accuracy of the GNSS-derived orthometric height have been analyzed to suggest the proper method to apply the determination of GNSS-derived orthometric height to the leveling loop disconnected area. As a result, it was found that two known points located near the unknown points need to be fixed in the leveling loop disconnected area. Further, 3 cm level of accuracy can be achieved if the GNSS survey is performed over two days, for four hours per day. In terms of the geoid model, the latest national geoid model should be applied rather than the EGM08 (Earth Gravitational Model 2008) to minimize regional bias and increase accuracy. Future research is necessary to apply the determination of the GNSS-derived orthometric height technique as a method to connect with the islands because the vertical reference system used inland and that used for the islands in Korea are still different.

Impacts of the Spaceflight to the Immune System

  • Sultonov, Doston;Kim, Young Hyo
    • Korean journal of aerospace and environmental medicine
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    • v.31 no.3
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    • pp.73-76
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    • 2021
  • Changes the gravity has a significant affect on the immune system. Astronauts experience the gravity changing during spaceflight, especially when launching and landing they experience hypergravity, and during spaceflight they feel microgravity. Both hypergravity and microgravity has an impact to the immune system, but not the same effect. These impacts have been investigated extensively during spaceflight in astronauts and in model experiments conducted on Earth as well. Astronauts during spaceflight feel the hypergravity, psychological stress, fear, high doses of radiation and microgravity. All these factors and changes may affect immune system directly or indirectly.

Design of Emergency Destruction System for Long-range Surface-to-Air Missile Flight Test (장거리 대공 유도탄 비행 시험을 위한 안전종료판단시스템 설계)

  • Eunyoung Noh
    • Journal of the Korea Institute of Military Science and Technology
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    • v.27 no.4
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    • pp.466-473
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    • 2024
  • An Emergency Destruction System is inevitable for ensuring safety both at sea and in populated areas, particularly during emergency detonations triggered by abnormal missile flight or upon mission completion. This paper introduces a novel method for developing an Emergency Destruction System capable of precisely calculating the Instantaneous Impact Point(IIP) during high-speed, maneuverable long-range surface-to-air missile flight tests. The Emergency Destruction System designed for long-range surface-to-air missile flight tests generates impact position tables that meticulously incorporate wind errors and navigation equations based on the Earth's ellipsoidal model. Factors such as the Coriolis effect and the direction of the gravitational acceleration vector are accounted for, significantly enhancing the accuracy of IIP determination amidst highly variable missile speed and attitude.