• Title/Summary/Keyword: Common Earth

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Foundation Research for Reinforced Concrete Substitution Grounding Electrode (철근콘크리트 대용접지극에 관한 기초 연구)

  • Kim, Sung-Sam;Lee, Chung-Sik;Koh, Hee-Seog
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.11a
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    • pp.305-308
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    • 2004
  • There are ground facility of maintenance in house electric facility of infra maintenance electric home appliances having used multifariousness in house, that use electric energy of common source for equipment. The body of building such as the reinforced concrete construction is structurally united, and the electric resistance is also small. It is possible that those foundations have contacted the ground at large surface area and that it substitutes the building construction body for the earth electrode. This is called "the structure earthing". This method has been defined at electrical facilities technical standards and KS in our country, and it has been used in various quarters practically. However, in our country, there is no example of using the foundation of the house as substitution earth electrode practically, and the means of the evaluation as electrode has not been established either. Then, in this paper, basic research for utilizing foundation of the house as substitution earth electrode is carried out.

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Wavenumber correlation analysis of satellite magnetometer observations

  • Kim, Jeong-Woo;Kim, Won-Kyun;Kim, Hye-Yun
    • Proceedings of the KSEEG Conference
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    • 2000.04b
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    • pp.311-313
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    • 2000
  • Identifying anomaly correlations between data sets is the basis for rationalizing geopotenial interpretation and theory. A procedure between the two or more geopotential data sets. Anomaly features that show direct, inverse, or no correlationsbetween the data may be separated by applying filters in the frequency domains of the data sets. The correlation filter passes or rejects wavenumbers between co-registered data sets based on the correlation coefficient between common wavenumbers as given by the cosine of their phase difference. This study includes as example of Magsat magnetic anomaly profile that illustrates the usefulness of the procedure for extracting correlative features between the sets.

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Information for Urban Risk Management: the Role of Remote and Close Sensing

  • Hofstee, Paul;Genderen, John van
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.162-164
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    • 2003
  • The multi-disciplinary research project Strengthening Local Authorities in Risk Management (SLARIM), initiated by ITC, includes three case study cities in Asia. An important question is: what are the essential data for risk management and how to access such data. The role of common sources (e.g. census data), data derived from remote sensing (high-resolution satellite imagery, aerial photos), and data from close sensing (field observation, including mobile GIS) to acquire essential risk management data will be discussed. Special attention is given to the question of the minimum area and to disaggregating population data. A few examples are given of Kathmandu / Lalitpur, Nepal.

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An Analysis of the High School 'Common Science' Contents and Textbooks (고등학교 ‘공통과학’의 교과내용 및 교과서 분석)

  • Lee, Gwang-Ho;Choi, Jong-Bum;Park, Moon-Kook;Cho, Kyu-Seong
    • Journal of the Korean earth science society
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    • v.18 no.6
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    • pp.453-463
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    • 1997
  • The contents of high school 'Common science' textbooks was analyzed qualitatively and quantitatively. Seven common science textbooks were selected and its contents, structure, inquiry, activities, appendix and its characteristics were investigated, and analyzed using the Goal Clusters of Project Synthesis and Romey's indices of text evaluation were calculated. The contents of each unit are not much different among textbooks because they are written according to the curriculum ordinance and textbook guidelines of the Ministry of Education. The textbooks was consist of $471{\sim}519$ pages. It was distribute similarly among the chapter of 'materials', 'forces', lives' and 'earth'. The chapter of 'energy' and 'environment' was treat significantly. The contents and structure of common science is a mere physical consolidation. I make an alternative plan that a topic form. Inquiry activities used in the textbooks are 11 type, however most of that is interpretation of data, experiment, survey and discussion. Ninety six percents of the experiment, belong to the 1st level, four percents of that belong to the 2nd level of the Schwab's inquiry level and there are no activities of the 3rd level. Little attention is given to Goal Cluster I, II, IV in the common science textbooks currently employed. Its content should be broadened to include all Goal Clusters of Project Synthesis. Homey's indices representing the degrees of student involvement. are $0.57{\sim}1.14$ for sentence analysis, $0.60{\sim}1.67$ for figure and diagram analysis, $0.67{\sim}1.50$ for analysis of questions at chapter ends, respectively, student activity per page investigated being $0.6{\sim}0.9$. But chapter summaries cease to repeats the conclusions of the chapter also it be rather formally and inattentively written.

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An Analysis of Sequence of Earth Science Content in Elementary School Curriculum in Korea and the U. S. (한국과 미국의 초등 과학 교육과정 지구영역의 학년 간 내용 연계성 분석 연구)

  • Suh, Ye-Won
    • Journal of Korean Elementary Science Education
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    • v.27 no.4
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    • pp.356-370
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    • 2008
  • The study aims to explore sequence of earth science content in elementary school science curriculum in Korea and the U.S.. The analysis is focused on a) general content structure of earth science part; b) concept relationship between grades in the specific field of 'geology'; c) longitudinal connection of concepts and content in 'geology.' The findings are as follows. First, earth science curriculum content in Korea is structured according to sub-scientific disciplines centering on not science concepts but topics or inquiry activities whereas the U.S. curricular content is organized through integrative earth science topics with basic concepts and sub-concepts. Second, it is a common feature that basic concepts are interrelated to sub-concepts in all grades in both countries. However, basic concepts are scattered all over the grades, presented in a linear pattern in Korea while those are provided together in 3rd grade and repeated with extended concepts in a spiral structure in the U.S.. Last, it is not clear how concepts and content are longitudinally connected between grades in Korean curriculum. On the contrary, concepts and content in the U.S. curriculum have a strong longitudinal connection between grades with conceptual hierarchy. Such results indicate that Korean elementary school science curriculum would limit students' comprehensive understanding of science concepts through grades. The study suggests Korean science content should strengthen interrelationship among concepts as well as longitudinal connection between grades, in order to achieve the ultimate goal of science education, 'scientific literacy'.

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Investigation of the 7th Grade Science-gifted Students' Understanding about the Lunar Phase through Their Own Observation and Interpretation

  • Kim, Eun-Sook;Yu, Hee-Won;Choe, Seung-Urn
    • Journal of the Korean earth science society
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    • v.32 no.5
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    • pp.514-520
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    • 2011
  • As homework, a total of 32 seventh grade science-gifted students were asked to observe the moon at daily intervals for one month duration. They were also asked to take the photos and to record relevant variables in a given format. The purpose of the task was to investigate what students thought, as they observed the moon. The results show that students paid attention mainly to the position of the moon relative to other variables such as the date in the lunar calendar, the observer's position on the earth, and the position of the sun. Overall students' response implied that students did not observe the lunar phase in relation with relevant variables. Some reponses from students show common misconceptions such as the cause of the lunar phase to reflect the shadow of the earth. However, some responses reveal students' idea that has been rarely reported in the previous researches. For example, some students drew the moon to revolve in the opposite direction. Significant number of students drew the sun's position to be due west before the full moon and due east after the full moon. Few students recognized the relation between the time of observation and observer's position on the earth. The results of current research suggest that not only the education but also the research needs to be expanded to consider informal environment such as the actual field conditions.

Ecophysiology of the kleptoplastidic dinoflagellate Shimiella gracilenta: I. spatiotemporal distribution in Korean coastal waters and growth and ingestion rates

  • Ok, Jin Hee;Jeong, Hae Jin;Kang, Hee Chang;Park, Sang Ah;Eom, Se Hee;You, Ji Hyun;Lee, Sung Yeon
    • ALGAE
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    • v.36 no.4
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    • pp.263-283
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    • 2021
  • To explore the ecophysiological characteristics of the kleptoplastidic dinoflagellate Shimiella gracilenta, we determined its spatiotemporal distribution in Korean coastal waters and growth and ingestion rates as a function of prey concentration. The abundance of S. gracilenta at 28 stations from 2015 to 2018 was measured using quantitative real-time polymerase chain reaction. Cells of S. gracilenta were detected at least once at all the stations and in each season, when temperature and salinity were 1.7-26.4℃ and 9.9-35.6, respectively. Moreover, among the 28 potential prey species tested, S. gracilenta SGJH1904 fed on diverse prey taxa. However, the highest abundance of S. gracilenta was only 3 cells mL-1 during the study period. The threshold Teleaulax amphioxeia concentration for S. gracilenta growth was 5,618 cells mL-1, which was much higher than the highest abundance of T. amphioxeia (667 cells mL-1). Thus, T. amphioxeia was not likely to support the growth of S. gracilenta in the field during the study period. However, the maximum specific growth and ingestion rates of S. gracilenta on T. amphioxeia, the optimal prey species, were 1.36 d-1 and 0.04 ng C predator-1 d-1, respectively. Thus, if the abundance of T. amphioxeia was much higher than 5,618 cells mL-1, the abundance of S. gracilenta could be much higher than the highest abundance observed in this study. Eurythermal and euryhaline characteristics of S. gracilenta and its ability to feed on diverse prey species and conduct kleptoplastidy are likely to be responsible for its common spatiotemporal distribution.

Heavy Metal Contamination of Roadside Gully-Pot Sediments, Seoul, Korea

  • Kim, Sung-Hwan;Lee, Pyeong-Koo;Yun, Seong-Taek;So, Chil-Sup
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.04a
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    • pp.222-225
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    • 2001
  • In urban environments, the surface land impermeability fundamentally related to urban growth emphasizes the environmental problems such as the storm water peak flow (so-called the urban flooding) and the pollution. The conventional urban drainage system provides a number of temporary reservoirs intercepting and retaining surface-derived pollutants following their introduction to and deposition upon the impermeable surface. Gully-pots are common features in urban drainage systems in Korea, which were installed for draining rainwater to prevent regurgitation in rainy season and retaining larger particles, hence minimizing pipe blockage problems. When the road runoff conveying sediment enters a gully-pot, the sediment mixes with the gully liquor causing direct pollution of receiving waters. The characteristics of local sediment contamination are usually related to the types of land use activities that take place or have taken place within the area., This study was undertaken to evaluate the spatial and temporal variations of the contamination of gully-pot sediments in Seoul with respect to heavy metals such as As, Cd, Co, Cr, Ni, Pb, Cu and Zn. The heavy metal data were examined according to the land use type. In this paper, sampling sites in Seoul were divided into six groups (commercial area, industrial area, residental area, motor way, rural area, and local pollution).

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Development of automatic alert populating system of earth structures based on sensor monitoring (센서 모니터링을 활용한 토류구조물 상황전파 자동화 시스템 개발)

  • Kim, Yong-Su;Ahan, Sang-Ro;Jung, Jae-Hyun;Han, Sang-Jea;Jung, Seung-Yong
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.667-672
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    • 2009
  • Gathering information and systemization of infrastructure disaster management is to reduce uncertainties in making decisions and maximize the number of alternations. The key objects of a sensor-based progress report and propagation automation systems are to provide objective data, realize and support decision making and deliver them to a certain area, department, manager and other people rapidly. The major findings and results of this study are as follows. 1) Application of international standard-based alerting protocol(CAP; Common Alerting Protocol). 2) Development of database of existing progress report and propagation manual in order to achieve networking of safety management on major social infrastructure of the nation. 3) Development middleware application programs to progress report and propagation data using SMS, FAX, EMS, VMS, MMS.

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The Effect of Learning Module Using, Cognitive Conflict Strategies on Secondary Pre-service Science Teachers Conceptual Change about Tide (인지갈등 전략을 적용한 학습모듈이 중등과학 예비교사의 조석 개념변화에 미치는 영향)

  • Jo, Jae-Hyung;Son, Jun-Ho;Song, Jin-Yeo;Jung, Ji-Hyun;Kim, Jong-Hee
    • Journal of the Korean Society of Earth Science Education
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    • v.10 no.1
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    • pp.26-37
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    • 2017
  • The purpose of this study was to investigate secondary pre-service science teachers' misconceptions of tide and to develop a learning module that can change misconceptions into scientific concepts and to examine the effect of the learning module for conceptual change. In order to achieve the purpose of the study, the researcher developed the test tool of tidal phenomena and the learning module using cognitive conflict strategy. The subjects of this study were 40 first year students who majored science education at a college of education in G metropolitan city. The results of this study are as follows. First, secondary pre-service science teachers had various misconceptions about tidal phenomena. Second, the developed learning module was effective in changing misconceptions about tide of pre-service science teachers into scientific concepts. However, some students had misconceptions about tidal phenomena after learning the developed module. The typical misconception was that they could not distinguish the centrifugal force generated when the earth and the moon revolve about the center of common mass as the center of rotation and the centrifugal force generated by the earth's rotation. And they did not know that they should not consider the earth's rotation while the earth was revolving around the center of common mass.