• Title/Summary/Keyword: Volcano

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Occurrence and Chemical Composition of Minerals from the Pallancata Ag Mine, Peru (페루 Pallancata 은 광산에서 산출되는 광물들의 산상 및 화학조성)

  • Yoo, Bong Chul;Acosta, Jorge
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.2
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    • pp.87-102
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    • 2019
  • Pallancata Ag mine is located at the Ayacucho region 520 km southeast of Lima. The geology of mine area consists of mainly Cenozoic volcanic-intrusive rocks, which are composed of tuff, andesitic lava, andesitic tuff, pyroclastic flow, volcano clasts, rhyolite and quartz monzonite. This mine have about 100 quartz veins in tuff filling regional faults orienting NW, NE and EW directions. The Ag grades in quartz veins are from 40 to 1,000 g/t. Quartz veins vary from 0.1 m to 25 m in thickness and extend to about 3,000 m in strike length. Quartz veins show following textures including zonation, cavity, massive, breccia, crustiform, colloform and comb textures. Wallrock alteration features including silicification, sericitization, pyritization, chloritization and argillitization are obvious. The quartz veins contain calcite, chalcedony, adularia, fluorite, rutile, zircon, apatite, Fe oxide, REE mineral, Cr oxide, Al-Si-O mineral, pyrite, sphalerite, chalcopyrite, galena, electrum, proustite-pyrargyrite, pearceite-polybasite and acanthite. The temperature and sulfur fugacity ($f_{s2}$) of the Ag mineralization estimated from the mineral assemblages and mineral compositions are ranging from 118 to $222^{\circ}C$ and from $10^{-20.8}$ to $10^{-13.2}atm$, respectively. The relatively low temperature and sulfur-oxygen fugacities in the hydrothermal fluids during the Ag mineralization in Pallancata might be due to cooling and/or boiling of Ag-bearing fluids by mixing of meteoric water in the relatively shallow hydrothermal environment. The hydrothermal condition may be corresponding to an intermediate sulfidation epithermal mineralization.

The Development of VR based Application for Realistic Disaster Prevention Training (현실감 있는 재난재해 예방 교육을 위한 VR 기반 앱 개발)

  • Kim, Taehoon;Youn, Junhee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.287-293
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    • 2018
  • The Korean peninsula has been known as an area that is free of volcanic disasters. However, recent observations and research results of volcanoes in Far East Asia, including Baedu Mountain and Japanese volcanoes, show that the Korean peninsula is no longer a safe area from volcanic disasters. Since 2012, the Korean government has been developing an IT-based construction technology, VDRS (Volcanic Disaster Response System), for effective volcanic disaster response system. The main users of VDRS are public officers in central or local governments. However, most of them have little experience and knowledge about volcanic disasters. Therefore, it is essential to develop education contents and implement training on volcanic disaster response for effective response in a real disaster situation. In this paper, we deal with the development of a mobile application based on virtual reality (VR) for realistic volcanic disaster response training. The objectives of training are the delivery of knowledge and experience for volcanic disasters. First, VR contents were generated based on spatial information. A 3D model was constructed based on a Digital Elevation Model (DEM), and visualization models for meterological effects and various volcanic disaster diffusion effects were implemented for the VR contents. Second, the mobile application for the volcanic disaster response training was implemented. A 12-step story board is proposed for volcanic disaster experience. The application was developed with the Unity3D engine based on the proposed story board to deliver knowledge of various volcanic disasters (volcanic ash, pyroclastic flows, volcanic mudflow etc.). The results of this paper will be used for volcanic disaster response and prevention training and for more realistic training linked with augmented reality technology in the future.

The Future of Countermobility Capability with a Literature Analysis from FASCAM to Terrain Shaping Obstacle(TSO) (미래 대기동 작전 능력의 발전방안 연구 -살포식지뢰(FASCAM)로부터 지형 조성 장애물(TSO) 전력을 중심으로-)

  • Park, Byoung-Ho;Sim, Jaeseong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.291-298
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    • 2021
  • In this study, the future of countermobility capability is presented by analyzing the status of the countermobility obstacles focusing on the history of landmines and munitions. The conventional landmine was forbidden globally by the CCW and Ottawa Treaty because it caused civilian damage after the war. Because the inhumanity of those mines had been acknowledged, shatterable mines with a self-destruct (SD) function and M93 "HORNET" anti-tank munition with enhanced sensors have been fielded. In 2016, the Obama administration announced a policy that banned all antipersonnel landmines, leaving a considerable gap in the countermobility capability. To deal with these problems, the developments of "SAVO" and the SLEP program of Volcano mines were conducted. In the sense of a long-term approach, the countermobility obstacles, including mines, were chosen as fundamental forces for Multi-Domain Operations and were improved to Terrain Shaping Obstacles (TSO). TSO has improved sensors and mobility kill capabilities and features an enhanced remote control over each munition on the battlefield through a network established with satellite communication. The combined arms countermobility might be fully capable until 2050 if the TSO program can be completed successfully.

Low Temperature CO Oxidation over Cu-Mn Mixed Oxides (Cu-Mn 혼합산화물 상에서 일산화탄소의 저온산화반응)

  • Cho, Kyong-Ho;Park, Jung-Hyun;Shin, Chae-Ho
    • Clean Technology
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    • v.16 no.2
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    • pp.132-139
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    • 2010
  • The Cu-Mn mixed oxide catalysts with different molar ratios of Cu/(Cu+Mn) prepared by co-precipitation method have been investigated in CO oxidation at $30^{\circ}C$. The catalysts used in this study were characterized by X-ray Diffraction (XRD), $N_2$ sorption, X-ray photoelectron spectroscopy (XPS), and $H_2$-temperature programmed reduction $(H_2-TPR)$ to correlate with catalytic activities in CO oxidation. The $N_2$ adsorption-desorption isotherms of Cu-Mn mixed oxide catalysts showed a type 4 having pore range of 7-20 nm and BET surface area was increased from 17 to $205\;m^2{\cdot}g^{-1}$ with increasing of Mn content. The XPS analysis showed the surface oxidation state of Cu and Mn represented $Cu^{2+}$and the mixture of $Mn^{3+}$ and $Mn^{4+}$, respectively. Among the catalysts studied here, Cu/(Cu+Mn) = 0.5 catalyst showed the highest activity at $30^{\circ}C$ in CO oxidation and the catalytic activity showed a typical volcano-shape curve with respect to Cu/(Cu+Mn) molar ratios. The water vapor showed a prohibiting effect on the efficiency of the catalyst which is due to the competitive adsorption of carbon monoxide on the active sites of catalyst surface and finally the formation of hydroxyl group with active metals.

Development and Effects Analysis of a Elementary School Scientific Inquiry Learning Module in a View of ESD: Focusing on 'Volcano and Earthquake' Unit (ESD(Education for Sustainable Development)를 적용한 초등학교 과학 탐구 학습 모듈 개발 및 효과분석: '화산과 지진' 단원을 중심으로)

  • Lim, Sung-man;Kim, Seongun
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.4
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    • pp.603-613
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    • 2017
  • The purpose of this study was to develop an scientific inquiry learning module by applying ESD and to verify its effect so that students could understand sustainable development and geology concepts by reconstructing the contents of the geology related unit. For this purpose, the "Volcanoes and Earthquakes" unit in the 3-4 grade group of the Korea national curriculum was selected and the scientific inquiry learning module was developed. The developed inquiry learning module consisted of one textbook and one teacher 's guidebook, and it was put into one class of elementary school to verify the effect. As a result, the teacher said that it was good to be taught contents of ESD and it was useful because of the concreteness of inquiry activities. The students responded that they were interesting because developed textbook is more often the interesting picture and activity than traditional textbook. And the students responded that 'ESD' has been an opportunity to be interested in science.

A Research on RC3(RMF-CMMC Common Compliance) meta-model development in preparation for Defense Cybersecurity (국방 사이버보안을 위한 RMF-CMMC 공통규정준수 메타모델 개발방안 연구)

  • Jae-yoon Hwang;Hyuk-jin Kwon
    • Journal of Internet Computing and Services
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    • v.25 no.1
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    • pp.123-136
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    • 2024
  • The U.S. Department of Defense, leading global cybersecurity policies, has two main cybersecurity frameworks: the Cybersecurity Maturity Model Certification (CMMC) for external defense industry certification, and the Risk Management Framework (RMF) for internal organizational security assessments. For Republic of Korea military, starting from 2026, the Korean version of RMF (K-RMF) will be fully implemented. Domestic defense industry companies participating in projects commissioned by the U.S. Department of Defense must obtain CMMC certification by October 2025. In this paper, a new standard compliance meta-model (R3C) development methodology that can simultaneously support CMMC and RMF security audit readiness tasks is introduced, along with the implementation results of a compliance solution based on the R3C meta-model. This research is based on practical experience with the U.S. Department of Defense's cybersecurity regulations gained during the joint project by the South Korean and U.S. defense ministries' joint chiefs of staff since 2022. The developed compliance solution functions are being utilized in joint South Korean-U.S. military exercises. The compliance solution developed through this research is expected to be available for sale in the private sector and is anticipated to be highly valuable for domestic defense industry companies that need immediate CMMC certification.

MT Response of a Small Island Model with Deep Sea and Topography (깊은 바다와 지형을 고려한 소규모 섬 모델의 MT 반응 연구)

  • Kiyeon Kim;Seong Kon Lee;Seokhoon Oh;Chang Woo Kwon
    • Geophysics and Geophysical Exploration
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    • v.27 no.1
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    • pp.37-50
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    • 2024
  • The magnetotelluric (MT) survey can be affected by external environmental factors. In particular, when acquiring MT data in islands, it is essential to consider the combined effect of topography and sea to understand the results and make accurate interpretations. To analyze the MT response (apparent resistivity, phase) with consideration of the effect of topography and sea, a small cone-shaped island model surrounded by deep sea was created. Two-dimensional (2-D) and three-dimensional (3-D) forward modeling were performed on the terrain model considering topography and the island model considering both topography and sea. The 2-D MT response did not reflect the topographic and sea effect of the direction orthogonal to the 2-D profile. The 3-D MT response included topographic and sea effects in all directions. The XY and YX components of the apparent resistivity were separated on undulating topography, such as a hill. A conductor at 1 km below sea level could be distinguished from topographic and sea effects in the MT response, and low resistivity anomaly was attenuated at greater depths. This study will facilitate understanding of field data measured on small islands.

A Simple Method Using a Topography Correction Coefficient for Estimating Daily Distribution of Solar Irradiance in Complex Terrain (지형보정계수를 이용한 복잡지형의 일 적산일사량 분포 추정)

  • Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.1
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    • pp.13-18
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    • 2009
  • Accurate solar radiation data are critical to evaluate major physiological responses of plants. For most upland crops and orchard plants growing in complex terrain, however, it is not easy for farmers or agronomists to access solar irradiance data. Here we suggest a simple method using a sun-slope geometry based topographical coefficient to estimate daily solar irradiance on any sloping surfaces from global solar radiation measured at a nearby weather station. An hourly solar irradiance ratio ($W_i$) between sloping and horizontal surface is defined as multiplication of the relative solar intensity($k_i$) and the slope irradiance ratio($r_i$) at an hourly interval. The $k_i$ is the ratio of hourly solar radiation to the 24 hour cumulative radiation on a horizontal surface under clear sky conditions. The $r_i$ is the ratio of clear sky radiation on a given slope to that on a horizontal reference. Daily coefficient for slope correction is simply the sum of $W_i$ on each date. We calculated daily solar irradiance at 8 side slope locations circumventing a cone-shaped parasitic volcano(c.a., 570m diameter for the bottom circle and 90m bottom-to-top height) by multiplying these coefficients to the global solar radiation measured horizontally. Comparison with the measured slope irradiance from April 2007 to March 2008 resulted in the root mean square error(RMSE) of $1.61MJ\;m^{-2}$ for the whole period but the RMSE for April to October(i.e., major cropping season in Korea) was much lower and satisfied the 5% error tolerance for radiation measurement. The RMSE was smallest in October regardless of slope aspect, and the aspect dependent variation of RMSE was greatest in November. Annual variation in RMSE was greatest on north and south facing slopes, followed by southwest, southeast, and northwest slopes in decreasing order. Once the coefficients are prepared, global solar radiation data from nearby stations can be easily converted to the solar irradiance map at landscape scales with the operational reliability in cropping season.

The impact of anthropogenic factors on changes in discharge and quality of water in the Hadano basin, Japan (인위적인 요인이 하천의 유량과 수질변화에 미친 영향 - 일본 하다노 분지를 사례 로 -)

  • ;Yang, Hea-Kun
    • Journal of the Korean Geographical Society
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    • v.30 no.3
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    • pp.242-254
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    • 1995
  • The Hadano Basin is located at a distance of about 70kms and 60kms from Tokyo and Yokohama and lies in the south-west part of the Kanto region in Japan. The basin area, which correspoends to the catchment of the Kaname River, is about areal size of 60.7$\textrm{km}^2$ and extends about length of 8kms in E-W direction and about width of 5kms in N-S direction (Fig.1). The Hadano basin is filled with thick pile of the alluvum from deposits composed of volcanic materials, mostly came from the Hakone Volcano and overlain by Fuji Volcanic ashes. Fluvial deposits form the good aquifer, therefore water resources of Handano City has been largely depending upon the eroundwater. Urbanization and industrialization of the basin has been rapid in the last thirty years, after activation of "Factory Attraction Policy of Hadano City" in 1956. Growth in population and number of factory due to urbanization changed the land-use pattern of the basin rapidly and increased the water demands. Therefore, Hadano City exploited a new source of water supply, and have introduced the prefectureal waterworks since 1976. On the other hand, the rapid urbanization has brought about the pollution of streams in the basin by domestic sewage and industrial waste water. Diffusion rate of sewerage systems in Hadano City is 38% in 1993. In ordcr to examine the impact of anthropogenic factors on river environments, the author took up the change of land-use and diffusion area of sewerage as parameters, and performed field surveys on water discharge and quality. The survey has been made at upstream and downstream of the main stream regularly per month, to get informati ons about the variation of discharge and water quality aiong the stream and its diurnal fluctuation. Annual variation has been analyzed based the data from Hadano City Office. The results are summarized as follows. 1. Stream discharge has been increasing by urbanization (Fig.3). Water quality (C $l^{-10}$ , N $H^{+}$$_{ 4}$-N, BOD) has been improving gradually after the application of sewerage service, yet water pollution load at the lower station has increased than that at the upper one because of the larger anthropogenic discharge volumes (Fig.4). 2. Corrclation coefficient of discharges between upper and lower was 0.81-0.92. Pollutant loads of the R. Kamame after the confluence with R. Kuzuha grew up by 2.4-3.7 times as compared with its upper reaches, and it increased to 3.7-6.9 times after the confluence with the R. Muro (Fig.5). 3. The changes of water quality along the stream can be divided into two groups (Fig.6a). First: water quality of the R. Kaname and R. Shijuhachisse is becoming worse towards the lower reaches because the water from branches are polluted. Second: water quality are improved in the lower where spring and small branch streams supply clear water, for example R. Mizunashi, R. Muro and R. Kuzuha. 4. Measured discharge at the upper station in the R. Shijuhachisse is 0.153㎥/sec, and about 55% of this is recharged until it reaches to the lower point. The R. Mizunashi has a discharge of 1.155㎥/sec at the upper point, is recharged 0.24㎥/sec until the midstream and groundwater spring 0.2㎥/sec at the lower reaches. R. Kuzuha recharged all the mountain runoff (0.2㎥/sec) at the upper reaches. The R. Muro is supplied by many springs and the estimated discharge of spring was 0.47㎥/sec (Fig.6b). 5. Diurmal variations in discharge and water quality are influenced clearly by domestic and industrial waste waters (Fig.7, 8).ed clearly by domestic and industrial waste waters (Fig.7, 8).

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Development and Application of Learning on Geological Field Trip Utilizing on Social Construction of Scientific Model (과학적 모델의 사회적 구성을 활용한 야외지질학습 개발 및 적용)

  • Choi, Yoon-Sung;Kim, Chan-Jong;Choe, Seung-Urn
    • Journal of the Korean earth science society
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    • v.39 no.2
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    • pp.178-192
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    • 2018
  • The purposes of this study were to develop and apply on learning on geological field trip utilizing the social construction of scientific model. We developed field trip places by considering not only Orion (1993)'s novelty space but also the achievement standards of 2015 national curriculum. The subjects of the study were 8 in the 'G' science gifted education center. We conducted a study using the theme of 'How was formed Mt. Gwanak?' on 5 lessons including a series of 2 field trip lessons and 3 lessons utilizing the social construction of scientific model. Students participated in pre- and post-test on the understanding of scientific knowledge about formation of mountain. Semi-structured interview was used to analyze students' learning about geological field trip in terms of affective domain. Results were as follows. First, there were 2 places of upper-stream valley and down-stream valley separately. They contained outcrops gneiss, granite, joint in the valley, xenolith, fault plane, mineral in the valley. Second, pre- and post-test and semi-structure interview were analyzed in terms of what scientific knowledge students learned about and how Mt. Gwanak was formed. Seven students explained that Mt. Gwanak was volcano during pretest. Seven students described how granite was formed to form Mt. Gwanak. They also understood geological time scale, i.e., metamorphic rock. Third, the geological field trip was effective to low achievement geoscience students as they engaged in the activities of field trip. Using positive responses on affective learning was effective on learning on geological field trip when utilizing the social construction of scientific model. This study suggests that teachers use an example 'model' on geoscience education. This study also suggests that teachers apply the social construction of scientific model to geological field trip.