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A Review on Monitoring Mt. Baekdu Volcano Using Space-based Remote Sensing Observations (인공위성 원격탐사를 이용한 백두산 화산 감시 연구 리뷰)

  • Hong, Sang-Hoon;Jang, Min-Jung;Jung, Seong-Woo;Park, Seo-Woo
    • Korean Journal of Remote Sensing
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    • v.34 no.6_4
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    • pp.1503-1517
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    • 2018
  • Mt. Baekdu is a stratovolcano located at the border between China and North Korea and is known to have formed through its differentiation stage after the Oligocene epoch in the Cenozoic era. There has been a growing interest in the magma re-activity of Mt. Baekdu volcano since 2010. Several research projects have been conducted by government such as Korea Meteorological Administration and Korea Institute of Geoscience and Mineral Resources. Because, however, the Mt. Baekdu volcano is located far from South Korea, it is quite difficult to collect in-situ observations by terrestrial equipment. Remote sensing is a science to analyze and interpret information without direct physical contact with a target object. Various types of platform such as automobile, unmanned aerial vehicle, aircraft and satellite can be used for carrying a payload. In the past several decades, numerous volcanic studies have been conducted by remotely sensed observations using wide spectrum of wavelength channels in electromagnetic waves. In particular, radar remote sensing has been widely used for volcano monitoring in that microwave channel can gather surface's information without less limitation like day and night or weather condition. Radar interferometric technique which utilized phase information of radar signal enables to estimate surface displacement such as volcano, earthquake, ground subsidence or glacial movement, etc. In 2018, long-term research project for collaborative observation for Mt. Baekdu volcano between Korea and China were selected by Korea government. A volcanic specialized research center has been established by the selected project. The purpose of this paper is to introduce about remote sensing techniques for volcano monitoring and to review selected studies with remote sensing techniques to monitor Mt. Baekdu volcano. The acquisition status of the archived observations of six synthetic aperture radar satellites which are in orbit now was investigated for application of radar interferometry to monitor Mt. Baekdu volcano. We will conduct a time-series analysis using collected synthetic aperture radar images.

Verification of Kompsat-5 Sigma Naught Equation (다목적실용위성 5호 후방산란계수 방정식 검증)

  • Yang, Dochul;Jeong, Horyung
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1457-1468
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    • 2018
  • The sigma naught (${\sigma}^0$) equation is essential to calculate geo-physical properties from Synthetic Aperture Radar (SAR) images for the applications such as ground target identification,surface classification, sea wind speed calculation, and soil moisture estimation. In this paper, we are suggesting new Kompsat-5 (K5) Radar Cross Section (RCS) and ${\sigma}^0$ equations reflecting the final SAR processor update and absolute radiometric calibration in order to increase the application of K5 SAR images. Firstly, we analyzed the accuracy of the K5 RCS equation by using trihedral corner reflectors installed in the Kompsat calibration site in Mongolia. The average difference between the calculated values using RCS equation and the measured values with K5 SAR processor was about $0.2dBm^2$ for Spotlight and Stripmap imaging modes. In addition, the verification of the K5 ${\sigma}^0$ equation was carried out using the TerraSAR-X (TSX) and Sentinel-1A (S-1A) SAR images over Amazon rainforest, where the backscattering characteristics are not significantly affected by the seasonal change. The calculated ${\sigma}^0$ difference between K5 and TSX/S-1A was less than 0.6 dB. Considering the K5 absolute radiometric accuracy requirement, which is 2.0 dB ($1{\sigma}$), the average difference of $0.2dBm^2$ for RCS equation and the maximum difference of 0.6 dB for ${\sigma}^0$ equation show that the accuracies of the suggested equations are relatively high. In the future, the validity of the suggested RCS and ${\sigma}^0$ equations is expected to be verified through the application such as sea wind speed calculation, where quantitative analysis is possible.

The Establishment of Labor Archive and Its New Development Strategy : An Attempt to Build Participatory Archive of the Institute of Labor History in SKHU (노동아카이브의 형성과 발전방향 모색 성공회대 노동사연구소의 '참여형 아카이브' 시도를 중심으로)

  • Lee, Chongkoo;Lee, Jaeseong
    • The Korean Journal of Archival Studies
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    • no.41
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    • pp.175-212
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    • 2014
  • In 2001 a large amount of labor record have been donated from Jeontaeil Labor Archive-Institute to SungKongHoe University(SKHU). Institute of Labor History in SKHU was established in the wake of the installation of the labor archive. Development of oral archive raised the awareness of the various relationships between the use and production of labor record. Interviewees of oral testimony expressed dissatisfaction and the role of the researchers was not sufficiently exhibited. Examining the main cases of Korea union movement history, we can find contradictions between the use and production of labor record clearly. Interval of interpretation and memory was too big between the parties of 'democratic' union movement in the 1970s. While among the parties who took part in Guro Alliance Strike of 1985, there is a group that remains in the "winner" in history on the one hand, but "loser" on the other without any reasonable criterion. Active intervention of the record users(researchers) is very limited. Among citizens or workers how will be resolved such "struggle of memory" in due process can not be seen. This is one of the reasons why labor archive is not rooted in the region. In this paper, I present a methodological alternatives for the production and use of records through the construction of participatory labor archive. Further, the reconstituted contents of the "documenting locality" strategy by complementing the theoretical part of the method of participation. The study of local and locality requires a "scale" dimension that will make up the identity recognition space, a memory and identity, a social relationship rather than the dimension of the physical space. Alternative "documenting locality" strategy will be able to contribute to solve the problems that occur between the production and use of the recording in labor archive.

Searle's Conception of Social Reality and the Problem of Freestanding Y Terms (설의 사회적 실재와 '비대응 Y항' 문제)

  • Noh, Yang-jin
    • Journal of Korean Philosophical Society
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    • v.141
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    • pp.43-62
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    • 2017
  • The main purpose of this paper is to survey the debates between Searle and Smith over the problem of "freestanding Y terms" in Searle's conception of social reality, and offer a viable solution, drawing on the experientialist conception of symbolic experience. Smith raises the problem of "freestanding Y term" against Searle's formula "X counts as Y in C" that there may be some cases where we cannot identify an X term to which an Y term refers. In case of an abstract concept such as equity, we may not find exactly what it stands for. That is, we cannot identify exactly what(X term) counts as equity. If there is nothing like an X for Y term, we can regard anything as equity, which may disrupt Searle's formula. Understandably, Smith does not say that the problem dismantles Searle's whole conception of social reality. Instead, Smith intends to show that Searle's formula is neither complete nor specific enough. Apparently, Searle admits that there may be freestanding Y terms and tries to articulate it within his formula, which does not seem to work. I suggest that the experientialist account of symbolic experience may serve to dissolve Smith's challenge, without modifying Searle's original formula. According to the experientialist conception of symbolization, we symbolically map some portion of our experience onto a physical object, which serves as a signifier, and we then understand and experience the signifier "in terms of" the mapped portion of experience. Thus, we experience certain buildings and some relevant people, say students, staffs, and professors in terms of "university." The status functions of university have been created by means of symbolic mappings, which change the way we understand and experience the buildings and people. In this picture, there need not be any notions such as "one-to-one correspondence" between X terms and Y terms. In this way, Searle may maintain his original formula, while dissolving, not answering, Smith's challenge. What Searle needs is a more appropriate theory of symbolization, part of which has been articulated by the experientialist account of symbolic experience.

Kant on 'the Highest Good of a Possible World' (칸트에서 '가능한 세계의 최고선')

  • PAEK, CHONG-HYON
    • Journal of Korean Philosophical Society
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    • no.96
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    • pp.39-70
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    • 2012
  • In order to locate Kant's concept of the highest good within ethics and the theory of moral religion, it needs to be approached with some qualifications: there are two rough ways to be suggested. The first way is to focus on the concept of the highest good that is explained in terms of the happiness in proportion to a rational being's virtue or to his/her worthiness to be happy. But the happiness determined in the sense outlined above would be (increasingly or decreasingly) changeable according to each one's individual morality-this is what is meant by each one's 'worthiness' here-, and would not be seen as the perfect one. It might even be said that this kind of happiness is possible in a sensible world generally taken, if the existence of God thought of as harmonizing natural phenomena and the moral order is successfully presupposed. The other way is to understand the concept of the highest good literally: in this view, the highest good shows that a rational being's character is completely appropriate to the moral law and for him/her, its corresponding idea, i.e., the perfect happiness, is considered with full justification. But the highest good in the sense sketched above-along with the existence of God and the immortality of the soul-is expected to be realized only in an intelligible world generally taken. This means that it should be appraised as an ideal of the highest good that includes the so-called 'physical happiness' specified in terms of the first way as its element. In this regard, it is seen to be somewhat restricted. Between the two concepts of the highest good already touched upon, the highest good of the possible world would be the one established in terms of the first way. In other words, it is not the highest good in an intelligible world, but the highest good in this world. Of course, it is true that we cannot help but assume the existence of God-a being as higher, as moral, as most holy, and as omnipotent-in order to explain the highest good in this world (namely, in order to establish the possibility of the combination of the happiness and the worthiness). For as long as both morally good acts and the happiness are considered to happen in a natural world, the cause of the nature (i.e., the existence of its creator), that is, God, must be able to be presupposed. In this vein, Kant interprets that most people view that the key of the Bible is to show that the best world which is characterized by an intelligible or heavenly kingdom is also actually feasible in this world. The wish of the people who have the morally good character is that God's kingdom comes and his will is properly achieved in this world. But we cannot know what God really does in order to realize his world in this world. Nonetheless, we are fully aware of what we should do in order to make ourselves a member of his world. It is specified like this: we should do our ethical duties and further proceed to establish an ethical community. Viewed this manner, it is concluded that an ethical community is not a merely ideal thing like the kingdom of the ends, but a human apparatus or institution that exists in this world.

Green-blue Coloured Cu-Zn Hydrated Sulfate Minerals from Gukjeon Mine in Miryang (밀양 국전광산의 녹-청색 구리-아연 수화황산염 광물)

  • Koo, Hyo Jin;Jang, Jeong Kyu;Do, Jin Young;Jeong, Gi Young;Cho, Hyen Goo
    • Economic and Environmental Geology
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    • v.51 no.6
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    • pp.473-483
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    • 2018
  • Green-blue coloured supergene minerals are covering host rocks along the gallery wall in the Gukjeon mine, a lead - zinc skarn deposit located in Miryang, Gyeongsangnam-do. These minerals have been described as azurite or malachite, but recent study recognized that the green minerals are devilline and blue minerals are Cu-Zn hydrated sulfates, but exact identification and detailed mineral characteristics are also not well known. In this study, we divide green-blue minerals into five groups (GJG) according to their external features and conducted XRD and SEM analyzes in order to identify mineral name and clarify the mineralogical characteristics. GJG-1, a bright bluish green group, consists of brochantite and quartz and GJG-2, a pale green colour with easily crumbly, of schulenbergite and a small amount of gypsum. Although pale blue GJG-3 and glassy lustrous bluish green GJG-4 have the same mineral assemblages with serpierite and gypsum in spite of different colour and luster, gypsum content may control the physical properties. GJG-5 with a gel phase mixture of pale blue and dark blue mineral is comprised of hydrowoodwardite, glaucocerinite, bechererite, serpierite and gypsum. The six green-blue minerals from the Gukjeon mine could be classified by Cu:Zn ratio, (Si + Al) content, Si:Al ratio, and Ca content. The physico-chemical environment of mineral formation is considered to be controlled by the geochemical factors in the surrounding fluid, and it looks forward that the accurate formation environment will be revealed through additional research. This paper gives greater mineralogical significance in the first report of several hydrated sulfate such as serpierite, glaucocerinite and bechererite in Korea. It has also rarely been reported the occurrence of several Cu-Zn hydrated sulfate in the same deposit in the world.

Study on Standardization of the Environmental Impact Evaluation Method of Extremely Low Frequency Magnetic Fields near High Voltage Overhead Transmission Lines (고압 가공송전선로의 극저주파자기장 환경영향평가 방법 표준화에 관한 연구)

  • Park, Sung-Ae;Jung, Joonsig;Choi, Taebong;Jeong, Minjoo;Kim, Bu-Kyung;Lee, Jongchun
    • Journal of Environmental Impact Assessment
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    • v.27 no.6
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    • pp.658-673
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    • 2018
  • Social conflicts with extremely low frequency magnetic field(ELF-MF) exposures are expected to exacerbate due to continued increase in electric power demand and construction of high voltage transmission lines(HVTL). However, in current environmental impact assessment(EIA) act, specific guidelines have not been included concretely about EIA of ELF-MF. Therefore, this study conducted a standardization study on EIA method through case analysis, field measurement, and expert consultation of the EIA for the ELF-MF near HVTL which is the main cause of exposures. The status of the EIA of the ELF-MF and the problem to be improved are derived and the EIA method which can solve it is suggested. The main contents of the study is that the physical characteristics of the ELF-MF affected by distance and powerload should be considered at all stages of EIA(survey of the current situation - Prediction of the impacts - preparation of mitigation plan ? post EIA planning). Based on this study, we also suggested the 'Measurement method for extremely low frequency magnetic field on transmission line' and 'Table for extremely low frequency magnetic field measurement record on transmission line'. The results of this study can be applied to the EIA that minimizes the damage and conflict to the construction of transmission line and derives rational measures at the present time when the human hazard to long term exposure of the ELF-MF is unclear.

Temporal Variations of Sea Water Environment and Nutrients in the East Coast of Korea in 2013~2017: Sokcho, Jukbyeon and Gampo Coastal Areas (2013~2017년 동해 연안의 해양환경과 영양염의 시간적 변동 : 속초, 죽변, 감포 연안)

  • Kwon, Kee-Young;Shim, Jeong Hee;Shim, Jeong-Min
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.4
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    • pp.457-467
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    • 2019
  • To investigate the long-term variation characteristics of nutrients in the east coast of Korea, water temperature, salinity, dissolved oxygen, and nutrients were measured at three stations of Sokcho, Jukbyeon and Gampo coasts for five years from 2013 to 2017. For five years, the water temperature of the East Sea coast was in the range of $1.2{\sim}28.8^{\circ}C$, the salinity was in the range of 30.63~34.79 and the dissolved oxygen (DO) was in the range of 3.53~7.64 mL/L. Distribution and variation of the water environment factors in the study area were determined by the vertical stratification of water column and distribution of water temperature. The high DO concentration in Sokcho coast From 2015 to August 2016 is presumed to be the result of the southward inflow of North Korean Cold Water (NKCW). Concentrations of dissolved inorganic nitrogen (DIN, $NH_4-N+NO_2-N+NO_3-N$) ranged $0.11{\sim}24.19{\mu}M$, phosphate concentration ranged $0.01{\sim}1.75{\mu}M$, and silicate ranged $0.17{\sim}32.80{\mu}M$. The N:P ratio was in the range of 0.7~54.3 (mean 15.2) and the N:P slope was in the range of 11.67~13.75. The N:P ratios in this study were lower than the Redfield ratio (16), indicating that nitrate did act as a limiting factor in phytoplankton growth. The correlation ($R^2$) of total N:P ratio was as high as 0.95, indicating that the effect of the surrounding land or non-point sources was not significant. In conclusion, the spatial and temporal variation of nutrients in the east coast of Korea was determined by the vertical mixing of water mass with thermocline and mainly affected by physical factors such as influx of external water masses and coastal upwelling, and the influences from inflows from the land were minimal.

Investigation of Microbial Contamination in Semisulcospira libertine and Evaluation of Its Reduction Effects by Sediment Removal Treatment (다슬기(Semisulcospira libertine)의 미생물 오염도 평가 및 해감 제거공정에 따른 저감화 효과)

  • Choi, Man-Seok;Jun, Eun Bi;Choi, Seungho;Bang, Hyeon-Jo;Park, Shin Young
    • Journal of Food Hygiene and Safety
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    • v.34 no.4
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    • pp.361-366
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    • 2019
  • In this study, microbial contamivation semisulcospira libertine and effect of sedimentation treatment of major bacterial and fungal pathogens were investigated. The total aerobic bacteria, coliforms, Escherichia coli, Staphylococcus aureus, and yeast and mold present in raw and water-dipped Semisulcospira libertine were enumerated using the standard plate count methods on using the standard plate method on potato dextrose agar (PDA), 3M Petrifilm for coliforms / E. coli, 3M Petrifilm for S. aureus, and plate count agar (PCA), respectively. In analysis of microbial contamination of raw Semisulcospira libertine, the total aerobic bacteria, coliforms, and yeast and mold were monitored as 6.40, 2.70, and $6.79{\log}_{10}CFU/g$, respectively. Both E. coli and S. aureus were not detected (detection limit: 10 CFU/g). However, Semisulcospira libertine dipped in ground water for 3 hours had higher contamination levels of all natural indigenous microorganisms than raw Semisulcospira libertine. Especially, E. coli was detected as $2.46{\log}_{10}CFU/g$ in the ground water-dipped Semisulcospira libertine. The total aerobic bacteria in the ground water-dipped Semisulcospira libertine was not significantly reduced (p>0.05) compared to that in the raw Semisulcospira libertine. Moreover, coliforms were significantly increased (p>0.05) in all water-dipped Semisulcospira libertine. Only fungi were slightly reduced (less than 0.2 log) (p>0.05) in the tap water-dipped Semisulcospira libertine by comparison with the raw Semisulcospira libertine. The results of this study suggest that the use of chemical sterilizing agents and other physical methods in the washing stage will be necessary for the microbial reduction in raw Semisulcospira libertine because the use of sediment removal treatment by ground or tap water did not affect the microbiological safety of the raw Semisulcospira libertine.

Changes in Aquatic Insect Community Structure in Wonju Stream based on a Comparison of Previous Studies (과거 문헌 비교를 통한 원주천 수서곤충 군집구조 변화)

  • Han, Jung Soo;Choi, Jun Kil;Won, Kyung Ho;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.36 no.3
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    • pp.400-411
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    • 2018
  • This study was a survey of the Wonju stream in Wonju city from May 2015 to September 2016. A total of three sites were selected from the upstream area Gwanseol-dong to the downstream area Hojeo-myeon. Physicochemical analysis, aquatic insect changes, cluster analysis, functional group analysis, rarefaction curve, and statistical analysis were compared between 2004 and 2016. A total of 19 species (38.78%) in 2004 and 22 species (36.67%) in 2016 were analyzed, with the largest number belonging to ephemeroptera. The individual ratio ranged from 27,759.2 (ind. $m^{-2}$, 84.30%) in 2004 to 4,573.2 (ind. $m^{-2}$, 41.64%) in 2016, with the highest number involving diptera. As a result of the community analysis, significant differences were detected in the indices of dominance, diversity, evenness, and richness in 2004 and 2016 (p<0.05). Burrowers of the habitat orientation groups showed the greatest variation with an average of -68.00% (${\pm}2.15$) and the collector-gatherers of the functional feeding groups showed the highest variation of -40.12% (${\pm}1.77$). The rarefaction curve analysis suggested that the species was the poorest in the midstream regions in 2004 and 2016. Physical factors and water quality showed a significant correlation with diversity index, evenness index, and the number of individuals. MDS analysis of the similarity of upstream and downstream regions was high in 2004, and low in 2016. The differences were attributed to physicochemical changes such as increase in flow velocity due to improvement of small dams and changes in bottom structure.