• Title/Summary/Keyword: natural joint

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Investigation of ground condition charges due to cryogenic conditions in an underground LNG storage plant (지하 LNG 저장 시험장에서 극저온 환경에 의한 지반상태 변화의 규명)

  • Yi Myeong-Jong;Kim Jung-Ho;Park Sam-Gyu;Son Jeong-Sul
    • Geophysics and Geophysical Exploration
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    • v.8 no.1
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    • pp.67-72
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    • 2005
  • To investigate the feasibility of a new concept of storing Liquefied Natural Gas (LNG) in a lined hard rock cavern, and to develop essential technologies for constructing underground LNG storage facilities, a small pilot plant storing liquid nitrogen (LN2) has been constructed at the Korea Institute of Geoscience and Mineral Resources (KIGAM). The LN2 stored in the cavern will subject the host rock around the cavern to very low temperatures, which is expected to cause the development of an ice ring and the change of ground condition around the storage cavern. To investigate and monitor changes in ground conditions at this pilot plant site, geophysical, hydrogeological, and rock mechanical investigations were carried out. In particular, geophysical methods including borehole radar and three-dimensional (3D) resistivity surveys were used to identify and monitor the development of an ice ring, and other possible changes in ground conditions resulting from the very low temperature of LN2 in the storage tank. We acquired 3D resistivity data before and after storing the LN2, and the results were compared. From the 3D images obtained during the three phases of the resistivity monitoring survey, we delineated zones of distinct resistivity changes that are closely related to the storage of LN2. In these results, we observed a decrease in resistivity at the eastern part of the storage cavern. Comparing the hydrogeological data and Joint patterns around the storage cavern, we interpret this change in resistivity to result from changes in the groundwater flow pattern. Freezing of the host rock by the very low temperature of LN2 causes a drastic change in the hydrogeological conditions and groundwater flow patterns in this pilot plant.

Geosites, Geoheritages and Geotrails of the Hwaseong Geopark, the Candidate for Korean National Geopark (화성 국가지질공원 후보지의 지질명소, 지질유산 그리고 지오트레일)

  • Cho, Hyeongseong;Shin, Seungwon;Kang, Hee-Cheol;Lim, Hyoun Soo;Chae, Yong-Un;Park, Jeong-Woong;Kim, Jong-Sun;Kim, Hyeong Soo
    • The Journal of the Petrological Society of Korea
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    • v.28 no.3
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    • pp.195-215
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    • 2019
  • Geopark is a new system for development of the local economy through conservation, education, and tourism that is an area of scientific importance for the earth sciences and that has outstanding scenic values. The Hwaseong Geopark, the candidate for Korean National Geopark is composed of 10 geosites: Gojeongri dinosaur egg fossils, Ueumdo, Eoseom, Ddakseom, Goryeom, Jebudo, Baengmiri Coast, Gungpyeonhang, Ippado and Gukwado geosites. In this study, geosites, geoheritages, and geotrails of the Hwaseong Geopark were described in detail, and the value and significane as a geopark were also discussed. The geology of the Hwaseong Geopark area belonging to the Gyeonggi Massif consists of the Precambrian metamorphic and meta-sedimentary rocks, Paleozoic sedimentary and metamorphic rocks, Mesozoic igneous and sedimentary rocks, and Quaternary deposits, indicating high geodiversity. The Gojeongri Dinosaur Egg Fossils geosite, designated as a natural monument, has a geotrail including dinosaur egg nest fossils, burrows, tafoni, fault and drag fold, cross-bedding. Furthermore, a variety of infrastructures such as eco-trail deck, visitor center are well-established in the geosite. In the Ueumdo geosite, there are various metamorphic rocks (gneiss, schist, and phyllite) and geological structures (fold, fault, joint, dike, and vein), thus it has a high educational value. The Eoseom geosite has high academic value because of the orbicular texture found in metamorphic rocks. Also, various volcanic and sedimentary rocks belonging to the Cretaceous Tando Basin can be observed in the Ddakseom and Goryeom geosites. In the Jebudo, Baengmiri Coast, and Gungpyeonghang geosites, a variety of coastal landforms (tidal flat, seastacks, sand and gravel beach, and coastal dunes), metamorphic rocks and geological structures, such as clastic dikes and quartz veins can be observed, and they also provide various programs including mudflat experience to visitors. Ippado and Gukwado geosites have typical large-scale fold structures, and unique coastal erosional features and various Paleozoic schists can be observed. The Hwaseong Geopark consists of outstanding geosites with high geodiversity and academic values, and it also has geotrails that combine geology, geomorphology, landscape and ecology with infrastructures and various education and experience programs. Therefore, the Hwaseong Geopark is expected to serve as a great National Geopark representing the western Gyeonggi Province, Korea.

Study on Material Characteristics and Conservation Methods for Tracksite of Cretaceous Dinosaurs and Pterosaurs of Jeongchon area in Jinju, Korea (진주 정촌면 백악기 공룡·익룡발자국 화석산지의 재질특성 및 보존 방안 연구)

  • Ji Hyun Yoo;Yu Bin Ahn;Myoung Nam Kim;Myeong Seong Lee
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.697-714
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    • 2023
  • The Tracksite of Cretaceous Dinosaurs and Pterosaurs in Jeongchon, Jinju was discovered in late 2017 during the construction of the Ppuri industry complex. This site is a natural heritage site with a high paleontological value, as it preserves fossils of various types of dinosaurs, pterosaurs, and animal traces at a dense concentration. In this study, we surveyed that physical weathering such as joint, crack, scaling, exfoliation, and fragmentation occurred through field research in the fossil site, and conducted basic research on conservation science to reduce the damage. To this end, among the eight levels identified after excavation, the rocks of Level 3, which yielded a large number of theropod footprint fossils, and Level 4, which yielded pterosaur footprint fossils, were analyzed for material characteristics and evaluation of the effectiveness of consolidation and adhesion. This results showed that the rocks in the Level 3 stratum were dark gray siltstone and the rocks in the Level 4 stratum were dark gray shale, which contained a large amount of calcite and were composed of quartz, plagioclase, mica, alkali feldspar, and other clay minerals, which are likely to be damaged by rainfall under external conditions. As a result of conducting an artificial weathering experiment by dividing the probationary sample into four groups: untreated, consolidation treatment, anti-swelling treatment, and adhesive treatment, the consolidation and the swelling inhibitor showed an effect immediately after treatment, but did not show a blocking effect under a freezing-thawing environment. The adhesive showed that the adhesive effect was maintained even under freezing-thawing conditions. In order to preserve the fossil sites at Jeongchon in the future, in addition to temporary measures to block the inflow of moisture, practical measures such as the construction of protective facilities should be prepared.

Rural Migration and Changes of Agricultural Population (농민이촌(農民離村)과 농업인구(農業人口)의 변화(變化))

  • Wu, Tsong-Shien;Kim, Kuong-Ho
    • Korean Journal of Agricultural Science
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    • v.1 no.1
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    • pp.91-116
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    • 1974
  • Taiwan agricultural development in the last decade has not been changed much since the accomplishment of land reform program. This is mainly due to the rapid development taken place within industry that agricultural development can not keep pace with. The increasing gap of rural-urban income discrepancy has caused socio-psychological unstability among rural people and inspire wants of out-migration. From 1961 to 1970, population of the ten largest cities showed an annual growth rate of 4.05%, while the population of the remainder of Taiwan showed 2.06%. Assuming the natural increase rate of these two population sections are similar, the difference of rural and urban annual growth rate can be at tributed to the flow of people from rural to urban sectors. The main objective of this paper is to identify the amount of agricultural out-migration and its impact on agricultural development and agricultural extension programs. Specifically, the objectives are to examine (1) rural-urban population composition (2) rural out-migration estimation (3) changes of agricultural population, and (4) implications for agricultural development and extension programs Some of the important findings are listed below; (1) The average agricultural out migration of the period 1960-1969 is estimated at around 60,000 per year. Take Tainan prefecture for example, the Male-Female Migration Ratio is 0.39 for age 20-24, 0.55 for age 25-29, 0.90 for 30-34. It is understood between age 20 and 34, the rural female migration rate is higher than the rural male. (2) Based on the population growth rate of 1950-1969, agricultural population is projected for the period of 1953 to 1989. By 1978, the agricultural population will reach its peak and begin to dedaine from 1980. The projected agricultural population in 1989 is 5,847,566 which occupies 29% of the Taiwan total population. (3) Assuming area of cultivated land keep unchanged as 905,263 ha. in 1970, and tif we can eliminate all 72% of part-time farms, then the average farm acreage for hose full-time farms will be increased to 3.6 hactares. This is unlikely to happen before 1989 without the government interference. (4) Less than 10% of adult farmer s of age 25-64 in 1969 enrolled in Farm Discussion Club, only 5% of adult farm women enrolled in Home Economics Club, and 5% of rural youth enrolled in 4-H Club. These statistics show a fact that only few farmers are reached by extension workers. Based on findings in this paper, some important suggestions are listed for future agricultural development. (1) Improve agricultural structure by decreasing agricultural population (a) Encourage farmers with less than 0.5 ha. of land to seek jobs outside of agriculture (b) Encourage joint cultivation and farm mechanization (c) Discourage rural migrants to Keep farm land (d) Provide occupational guidance program through extension education programs (2) Establish future farmers settlement project to assure rural youth have enough resources for farming. (3) An optimum Population policy should be integrated into rural socio-economic development and national development programs.

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A Study on the Tree Surgery Problem and Protection Measures in Monumental Old Trees (천연기념물 노거수 외과수술 문제점 및 보존 관리방안에 관한 연구)

  • Jung, Jong Soo
    • Korean Journal of Heritage: History & Science
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    • v.42 no.1
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    • pp.122-142
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    • 2009
  • This study explored all domestic and international theories for maintenance and health enhancement of an old and big tree, and carried out the anatomical survey of the operation part of the tree toward he current status of domestic surgery and the perception survey of an expert group, and drew out following conclusion through the process of suggesting its reform plan. First, as a result of analyzing the correlation of the 67 subject trees with their ages, growth status. surroundings, it revealed that they were closely related to positional characteristic, damage size, whereas were little related to materials by fillers. Second, the size of the affected part was the most frequent at the bough sheared part under $0.09m^2$, and the hollow size by position(part) was the biggest at 'root + stem' starting from the behind of the main root and stem As a result of analyzing the correlation, the same result was elicited at the group with low correlation. Third, the problem was serious in charging the fillers (especially urethane) in the big hollow or exposed root produced at the behind of the root and stem part, or surface-processing it. The benefit by charging the hollow part was analyzed as not so much. Fourth, the surface-processing of fillers currently used (artificial bark) is mainly 'epoxy+woven fabric+cork', but it is not flexible, so it has brought forth problems of frequent cracks and cracked surface at the joint part with the treetextured part. Fifth, the correlation with the external status of the operated part was very high with the closeness, surface condition, formation of adhesive tissue and internal survey result. Sixth, the most influential thing on flushing by the wrong management of an old and big tree was banking, and a wrong pruning was the source of the ground part damage. In pruning a small bough can easily recover itself from its damage as its formation of adhesive tissue when it is cut by a standard method. Seventh, the parameters affecting the times of related business handling of an old and big tree are 'the need of the conscious reform of the manager and related business'. Eighth, a reform plan in an institutional aspect can include the arrangement of the law and organization of the old and big tree management and preservation at an institutional aspect. This study for preparing a reform plan through the status survey of the designated old and big tree, has a limit inducing a reform plan based on the status survey through individual research, and a weak point suggesting grounds by any statistical data. This can be complemented by subsequent studies.

The Liability for Space Activity of Launching State of Space Object and Improvement of Korea's Space Policy (우주물체 발사국의 우주활동에 대한 책임과 우리나라 우주정책의 개선방향)

  • Lee, Kang-Bin
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.2
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    • pp.295-347
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    • 2013
  • Korea launched the science satellite by the first launch vehicle Naro-ho(KSLV-1) at the Naro Space Center located at Oinarodo, Cohenggun Jellanamdo in August, 2009 and October, 2010. However, the first and second launch failed. At last, on January 30, 2013 the third launch of the launch vehicle Naro-ho has successfully launched and the Naro science satellite penetrated into the space orbit. Owing to the succeed of the launch of Naro-ho, Korea joined the space club by the eleventh turn following the United States, Russia, Japan and China. The United Nations adopted the Outer Space Treaty of 1967, the Rescue Agreement of 1968, the Liability Convention of 1972, the Regislation Convention of 1976, and Moon Agreement of 1979. Korea ratified the above space-related treaties except the Moon Agreement. Such space-related treaties regulate the international liability for the space activity by the launching state of the space object. Especially the Outer Space Treaty regulates the principle concerning the state's liability for the space activity. Each State Party to the Treaty that launches or procures the launching of an object into outer space is internationally liable for damage to another State Party or to its natural or judicial persons by such object or its component parts on the earth, in air space or in outer space. Under the Liability Convention, a launching state shall be absolutely liable to pay compensation for damage caused by its space object on the surface of the earth or to aircraft in flight. The major nations of the world made national legislations to observe the above space-related treaties, and to promote the space development, and to regulate the space activity. In Korea, the United States, Russia and Japan, the national space-related legislation regulates the government's liability of the launching state of the space object. The national space-related legislations of the major nations are as follows : the Outer Space Development Promotion Act and Outer Space Damage Compensation Act of Korea, the National Aeronautic and Space Act and Commercial Space Launch Act of the United States, the Law on Space Activity of Russia, and the Law concerning Japan Aerospace Exploration Agency and Space Basic Act of Japan. In order to implement the government's liability of the launching state of space object under space-related treaties and national legislations, and to establish the standing as a strong space nation, Korea shall improve the space-related policy, laws and system as follows : Firstly, the legal system relating to the space development and the space activity shall be maintained. For this matter, the legal arrangement and maintenance shall be made to implement the government's policy and regulation relating to the space development and space activity. Also the legal system shall be maintained in accordance with the elements for consideration when enacting the national legislation relevant to the peaceful exploration and use of outer space adopted by UN COPUOS. Secondly, the liability system for the space damage shall be improved. For this matter, the articles relating to the liability for the damage and the right of claiming compensation for the expense already paid for the damage in case of the joint launch and consigned launch shall be regulated newly. Thirdly, the preservation policy for the space environment shall be established. For this matter, the consideration and preservation policy of the environment in the space development and use shall be established. Also the rule to mitigate the space debris shall be adopted. Fourthly, the international cooperation relating to the space activity shall be promoted. For this matter, the international cooperation obligation of the nation in the exploration and use of outer space shall be observed. Also through the international space-related cooperation, Korea shall secure the capacity of the space development and enter into the space advanced nation.

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