• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.106-106
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• 2014

SIGMA (Scientific cubesat with Instrument for Global Magnetic field and rAdiation)는 근 지구공간에서 우주방사선량 측정과 자기장 변화 검출의 과학적 목적과 교육적 목적을 가지고 개발하고 있는 초소형 큐브위성이다. $100mm{\times}100mm{\times}340.5mm$의 크기로 약 3.6 kg의 무게를 가지며, 탑재체는 방사선에 대하여 인체와 동일한 산란 흡수 특성을 가진 Tissue Equivalent Proportional Counter (TEPC)와 자기장 측정을 위한 Magnetometer (Mag)이다. 위성체는 구조계, 자세제어계, 전력계, 명령 및 데이터처리계, 통신계로 구성되어있다. 구조계는 위성의 뼈대인 Chassis와 Mag deployer로 이루어져있고, 위성의 안정적인 자세유지를 목적으로 Attitude Control System (ACS) Board와 Torque Coil이 자세제어계로 구성된다. 전력의 생산과 공급 및 충전은 태양전지판과 Electrical Power System (EPS), 리튬 배터리로 구성된 전력계에서 이뤄지며, 명령 및 데이터처리계는 On Board Computer (OBC)와 Instrument Interface board (IIB)를 중심으로 서브시스템의 명령체계와 데이터처리를 다룬다. 통신계는 Uplink인 VHF 안테나와 Downlink인 UHF, S-band 안테나로 구성되며 지상과 명령을 송수신한다. SIGMA는 타임인터럽트 기능을 활용한 Flight Software (FSW)로 운용되며 임무에 따른 6가지 모드의 시나리오로 위성을 운용한다. 이에 SIGMA의 개발과 테스트 결과를 소개한다. 본 큐브위성 개발기술을 바탕으로 향후 천문관측용 위성에도 활용할 예정이다.

• The Journal of Engineering Geology
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• v.30 no.1
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• pp.71-84
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• 2020

Various geological structures are found on the slope of Bangnim district in Pyeongchang, Gangwon-do, based on the Paleozoic Joseon Supergroup Limestone. The recumbent fold observed on the slope is a very rare geological structure that has not been found in Korea, and has important academic value in exploring the formation process of the Paleozoic geological structures in the Gangwon region. In this study, discussed the geological value of the geological structure observed on the slope of the road, and studied the management method of rockfall problem slopes. The state of development of recumbent folds has conservation value in geological scarcity and specificity. Preservation management measures should be prepared through the protection of slopes and measures to reduce of rockfall risks as geoheritage with an important value in geology science and education. Furthermore, it is expected to be preserved and utilized as a geopark.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.2
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• pp.143-150
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• 2013

The Honolulu Strategy is a framework document to address marine debris issue globally. The Fifth International Marine Debris Conference held in March 2011 and organized by NOAA and UNEP catalyzed the development of the Holonulu Strategy. Goals of the Strategy are to reduce the amount and impact of land-based, sea-based, and accumulated marine debris. A set of strategies for each goal were provided for education and awareness, legislation, and alternative technologies. The Strategy also lists indicators that could be used to evaluate outcomes of strategies. The adoption of the Honolulu Strategy by the international community has led the international organizations such as GPA, IMO, and CBD to strengthen their responses to the marine debris issue. UN has also set up specific actions that will be implemented until 2025 through its resolutions on marine debris. Recent global developments related to the marine debris issue might lead to a change in the character of the international marine debris management from the current soft law regime to a mandatory one. The Honolulu Strategy could provide a guideline when the Korean government formulates the Second Basic Plan for Marine Debris Management, especially with its prevention-oriented approaches, utilization of scientific policy development tools, and adoption of evaluation system using performance indicators.

• Korean Journal of Remote Sensing
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• v.24 no.4
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• pp.273-287
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• 2008

Characteristics of skin-bulk sea surface temperature (SST) differences in the Northeast Asia seas were analyzed by utilizing 845 collocated matchup data between NOAA/AVHRR data and oceanic in-situ temperature measurements for selected months from 1994 to 2003. In order to understand diurnal variation of SST within a few meters of the upper ocean, the matchup database were classified into four categories according to day-night and drifter-shipboard measurements. Temperature measurements from daytime drifters showed a good agreement with satellite MCSST (Multi-Channel Sea Surface Temperature) with an RMS error of about $0.56^{\circ}C$. Poor accuracy of SST with an rrns error of $1.12^{\circ}C$ was found in the case of daytime shipboard CTD (Conductivity, Temperature, Depth) measurements. SST differences between MCSST and in-situ measurements are caused by various errors coming from atmospheric moist effect, coastal effect, and others. Most of the remarkable errors were resulted from the diurnal variation of vertical temperature structure within a few meters as well as in-situ oceanic temperatures at different depth, about 20 cm for a satellite-tracked drifting buoy and a few meters for shipboard CTD or moored buoy. This study suggests that satellite-derived SST shows significant errors of about ${\pm}3^{\circ}C$ in some cases and therefore it should be carefully used for one's purpose on the base of in-depth understanding of skin-bulk SST difference and vertical temperature structure in regional sea.

• Economic and Environmental Geology
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• v.52 no.2
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• pp.189-197
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• 2019

HLW (High Level Radioactive Waste) is one of the problems that must be solved in the countries that implement nuclear power generation. Most countries that are concerned about HLW treatment are considering complete isolation from human society by disposing them deep underground. For perfect isolation, understanding the characteristics of underground rocks is very important. In particular, understanding the characteristics of discontinuity as a path way is one of the first things in order to predict the movement of exposed nuclear species to the surface. In this study, we used 500m underground core samples obtained from granite and gneiss area. The purpose of this study is to understand the characteristics of the discontinuities in each rock type and to analyze the properties of the joints in the underground relative to the surrounding environment. For this purpose, the types of discontinuities were classified and the distribution of each discontinuity were analyzed through visual analysis of the each sample obtained at 500m underground. This study can be used as a basic data for understanding the properties of discontinuities in the rock of the survey area and it can be also used as an important data for understanding the distribution characteristics of discontinuities according to the rock types.

• The Journal of the Petrological Society of Korea
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• v.28 no.1
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• pp.15-24
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• 2019

There are beautiful scenery with columnar jointing at 15 valley of southern slope of the Wangtian'e volcano in Mt. Baekdu volcanic field. The compositions of phenocryst minerals which have porphyritic textures in mafic volcanic rocks of this area were carried out. The Wangtian'e volcano consists of Changbai basalt~trachybasalt (lower part) and Wangtian'e basaltic trachyandesite~trachyte~alkali rhyolite (upper part). This study is focused on the mafic rocks of the Changbai trachybsalt and the Wangtian'e basaltic trachyandesite. Main phenocrysts are feldspar, pyroxene and olivine. The major element compositions of the phenocrysts were analyzed using EPMA. Plagioclase phenocrysts of the Wangtian'e basaltic trachyandesite are located at the border of andesine and oligoclase ($An_{24.1{\sim}36.0}$) in the An-Ab-Or diagram, and those of the Changbai trachybasalt are labradorite ($An_{54.2{\sim}65.2}$). Pyroxene phenocrysts are augite. Olivine phenocrysts of the Changbai trachybsalt are crysolite ($Mg_{0.79-0.77}Fe_{0.21-0.23}$) and microphenocrysts in the groundmass are hyalosiderite ($Mg_{0.58-0.56}Fe_{0.42-0.44}$). Calculated crystallization temperature of olivine phenocrysts is $1196{\sim}1123^{\circ}C$, clinopyroxene is $1122{\sim}1112^{\circ}C$, phenocrysts and laths of plagioclases are $1118{\sim}1107^{\circ}C$ and $1091{\sim}1089^{\circ}C$, respectively. The temperatures suggests that the olivine phenocrysts, clinopyroxene, plagioclase phenocrysts, and plagioclase laths were crystallized in the magma chamber in sequence.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.4
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• pp.81-93
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• 2022

There are many natural hot springs and mineral springs as well as the cultural heritage of the three kingdoms period in the Geum River basin including Chungcheong region. No specific regeneration and publicity plans for deteriorated facilities in this area has been presented. This study aims to suggest promising hot spots and complex water culture belt in the Chungcheong region and Geum River basin through the spatial interpretation of resources. The northern part of the Geum River basin is expected to become a therapeutic spring belt with many hot springs and CO₂-rich springs. In the central and southern parts of the Geum River basin, it is considered that it will be possible to promote convergence publicity by using groundwater resources and cultural assets.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.241-263
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• 2010

KoFlux is a Korean network of micrometeorological tower sites that use eddy covariance methods to monitor the cycles of energy, water, and carbon dioxide between the atmosphere and the key terrestrial ecosystems in Korea. KoFlux embraces the mission of AsiaFlux, i.e. to bring Asia's key ecosystems under observation to ensure quality and sustainability of life on earth. The main purposes of KoFlux are to provide (1) an infrastructure to monitor, compile, archive and distribute data for the science community and (2) a forum and short courses for the application and distribution of knowledge and data between scientists including practitioners. The KoFlux community pursues the vision of AsiaFlux, i.e., "thinking community, learning frontiers" by creating information and knowledge of ecosystem science on carbon, water and energy exchanges in key terrestrial ecosystems in Asia, by promoting multidisciplinary cooperations and integration of scientific researches and practices, and by providing the local communities with sustainable ecosystem services. Currently, KoFlux has seven sites in key terrestrial ecosystems (i.e., five sites in Korea and two sites in the Arctic and Antarctic). KoFlux has systemized a standardized data processing based on scrutiny of the data observed from these ecosystems and synthesized the processed data for constructing database for further uses with open access. Through publications, workshops, and training courses on a regular basis, KoFlux has provided an agora for building networks, exchanging information among flux measurement and modelling experts, and educating scientists in flux measurement and data analysis. Despite such persistent initiatives, the collaborative networking is still limited within the KoFlux community. In order to break the walls between different disciplines and boost up partnership and ownership of the network, KoFlux will be housed in the National Center for Agro-Meteorology (NCAM) at Seoul National University in 2011 and provide several core services of NCAM. Such concerted efforts will facilitate the augmentation of the current monitoring network, the education of the next-generation scientists, and the provision of sustainable ecosystem services to our society.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.3
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• pp.263-276
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• 2021

Marine benthic organisms have been used as the indicators for the environment assessment and recently considered as a very important component in the biodiversity and ecosystem restoration. In Korean waters, the quantitative data on marine benthos was used as one of major components for the marine pollution assessment for 50 years since 1970s. The species identification which is an important factor for the quantitative biological data was mainly performed by the marine benthic ecologists. This leads to the deterioration of the data quality on marine benthos from the misidentication of major taxonomic groups due to the lack of taxonomic expertise in Korea. This taxonomic problem has not been solved until now and remains in most data from national research projects on the marine ecosystems in Korean waters. Here we introduce the quality assurance and control (QA/QC) system for the marine biological data in UK, that is, NMBAQC (Northeast Atlantic Marine Biological Analytic and Quality Control) Scheme which has been performed by private companies to solve similar species identification problems in UK. This scheme asks for all marine laboratories which want to participate to any national monitoring programs in UK to keep their identification potency at high level by the internal quality assurance systems and provides a series of taxonomic workshops and literature to increase their capability. They also performs the external quality control for the marine laboratories by performing the Ring Test using standard specimens on various faunal groups. In the case of Korea, there are few taxonomic expertise in two existing national institutions and so they can't solve the taxonomic problems in marine benthic fauna data. We would like to provide a few necessary suggestions to solve the taxonomic problems in Korean marine biological data in short-terms and long-terms: (1) the identification of all dominant species in marine biological data should be confirmed by taxonomic expertise, (2) all the national research programs should include taxonomic experts, and (3) establishing a private company, like the Korea marine organism identification association (KMOIA), which can perform the QA/QC system on the marine organisms and support all Korean marine laboratories by providing taxonomic literature and species identification workshops to enhance their potency. The last suggestion needs more efforts and time for the establishment of that taxonomic company by gathering the detailed contents and related opinions from diverse stakeholders in Korea.

• The Journal of Engineering Geology
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• v.33 no.1
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• pp.169-187
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• 2023

Aggregates from 84 cities and counties in Korea were tested for quality to allow analysis of the physical characteristics of aggregates from river, land, and forest environments. River and land aggregates were analyzed for 18 test items, and forest aggregates for 12 test items. They were classified according to watershed and geology, respectively. The observed physical characteristics of the river aggregates by basin were as follows: aggregates from the Geum River basin passed through 2.5, 1.2, 0.6, 0.3, 0.15, and 0.08 mm sieves; clay lumps constituted the Nakdong River basin material; aggregates from the Seomjin River basin passed through 10, 5, and 2.5 mm sieves; those from the Youngsang River basin passed through 1.2, 0.6, 0.3, 0.15, and 0.08 mm sieves; and aggregates from the Han River basin passed through 10, 5, 2.5, 1.2, 0.6, 0.3, and 0.08 mm sieves, Stability; Standard errors were analyzed for the average amount passing through 10, 0.6, and 0.08 mm silver sieves, and performance rate showed different distribution patterns from other physical characteristics. Analysis of variance found that 16 of the 18 items, excluding the absorption rate and the performance rate, had statistically significant differences in their averages by region. Considering land aggregates by basin, those from the Nakdong River basin excluding the Geum River basin had clay lumps, those from the Seomjin River basin had 10 and 5 mm sieve passage, aggregates from the Youngsang River basin had 0.08 mm sieve passage, and those from the Han River basin had 10, 0.6, and 0.08 mm sieve passage. The standard error of the mean of the quantity showed a different distribution pattern from the other physical characteristics. Analysis of variance found a statistically significant difference in the average of all 18 items by region. Analyzing forest aggregates by geology showed distributions of porosity patterns different from those of other physical characteristics in metamorphic rocks (but not igneous rocks), and distributions of wear rate and porosity were different from those of sedimentary rocks. There were statistically significant differences in the average volume mass, water absorption rate, wear rate, and Sc/Rc items by lipid.