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Topography and Soil Characteristics Related to Land Creep in 37 Areas in South Korea (우리나라 37개 땅밀림지의 지질 및 토양 특성)

  • Park, Jae-Hyeon;Seo, Jung Il;Ma, Ho-Seop;Kim, Dongyeob;Kang, Minjeng;Kim, Kidae
    • Journal of Korean Society of Forest Science
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    • v.108 no.4
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    • pp.540-551
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    • 2019
  • This study was conducted to provide basic data for classifying patterns of land creep in 37 areas in South Korea using geological and soil property analyses. Geological time, as it relates to land creep areas in South Korea, had been most impactful for the Gyeongsang Supergroup and its sedimentary bedrock during the Cretaceous period. In this area, perfect ridge cliffs in land creeping areas included 20 plots (approximately 54.0%), while tension cracking areas with ambiguous ridge cliff characteristics included 17 plots (approximately 46.0%). Hesitant slide slope types included 20 plots (approximately 54.0%) within theslide slope of an incident pattern (slide slope figure) in land creeping areas. Colluvial debris types among land creep patterns were the most frequent and included 25 plots (approximately 68.0%). The direct causes of land creep were cutting of foothills, quarrying, land-clearing in mountains, mining exploration, and the creation of burial grounds, all of which added to geological impacts. Among land creeping areas, 27 plots (approximately 73.0%) were the result of man-made activities, and 10 plots (approximately 27.0%) were derived via natural causes such as earthquakes, heavy rainfall, and caving.

An Analysis of the Economic Effects of Corporate Accumulated Earnings Tax System (기업소득 환류세제의 경제적 효과분석)

  • Kim, Dong-Hun
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.1
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    • pp.367-380
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    • 2020
  • Recently, Korea's economy is facing a difficult economic situation due to sluggish domestic demand, low corporate investment and a cliff in youth employment. In order to overcome this problem and turn the economy into a virtuous circle, the government has introduced and implemented various economic policies. In this study, the effects of the corporate accumulated earnings tax system included in the 2014 tax code revision were to be verified. The validity of the business income was verified and analyzed using the financial data of the entity as to whether the income of the entity was being circulated to household income. First, validating the validity of whether the income tax on non-current income affects the level of an entity's investment, the results showed significant negative effects at a significant level of 5 per cent. Second, the analysis of whether the return tax on corporate income is affecting management decisions that increase the level of dividends for an entity has identified a metaphorical positive relationship. Third, it was confirmed that the income tax on uncurrency income does not have a significant effect on the increase in wages for workers. The result is presumed to be the main reason for the increased uncertainty in the economy and business environment.

Volcanic Processes of Dangsanbong Volcano, Cheju Island (제주도 당산봉 화산의 화산과정)

  • 황상구
    • The Journal of the Petrological Society of Korea
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    • v.7 no.1
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    • pp.1-14
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    • 1998
  • Dangsanbong volcano, which is located on the coast of the western promontory of Cheju Island, occurs in such a regular pattern on the sequences which represent an excellent example of an eruptive cycle. The volcano comprises a horseshoe-shaped tuff cone and a younger nested cinder cone on the crater floor, which are overlain by a lava cap at the top of the cinder cone, and wide lava plateau in the moat between two cones and in the northern part. The volcanic sequences suggest volcanic processes that start with Surtseyan eruption, progress through Strombolian eruption and end with Hawaiian eruption, and then are followed by rock fall from sea cliff of the tuff cone and by air fall from another crater. It is thought that the eruptive environments of the tuff cone could be mainly emergent because the present cone is located on the coast, and standing body of sea water could play a great role. It is thought that the now emergent part of the tuff cone was costructed subaerially because there is no evidence of marine reworking. The emergent tuff cone is characterized by distinctive steam-explosivity that results primarily from a bulk interaction between rapidly ascending magma and external water. The sea water gets into the vent by flooding accross or through the top or breach of northern tephra cone. Dangsanbong tuff cone was constructed from Surtseyan eruption which went into with tephra finger jetting explosion in the early stage, late interspersed with continuous upruch activities, and from ultra-Surtseyan jetting explosions producting base surges in the last. When the enclosure of the vent by a long-lived tephra barrier would prevent the flooding and thus allow the vent to dry out, the phreatomagmatic activities ceased to transmit into magmatic activity of Strombolian eruption, which constructed a cinder cone on the crater floor of the tuff cone Strombolian eruption ceased when magma in the conduit gradually became depleted in gas. In the Dangsanbong volcano, the last magmatic activity was Hawaiian eruption which went into with foundation and effusion of basalt lava.

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Type and Characteristics of Debris Landform in Mt. Mudeung (무등산 암설지형의 유형과 특징)

  • Oh, Jong-Joo;Park, Seoung-Phill;Seong, Yeong-Bae
    • Journal of the Korean association of regional geographers
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    • v.18 no.3
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    • pp.253-267
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    • 2012
  • The study looked into the type and characteristics of debris landforms in Mt. Mudeung. By focusing on the representative area, we aimed to categorize the debris landforms based on the morphologic and genetic characteristcis. The types of debris areas in Mt. Mudeung can be divided into the exposed debris type, mixed type of matrix, and the boulder-hidden type. Supply of block in the debris slope area displays different features depending on types of rocks. For the stony slopes of andesite, the block must be moved from the columnar joint or cliff in the upper part. The andesite debris slopes display dominant edge shape while displaying no round shape. The granite stony slopes display dominant round shape and the present exposed slope was assumed to be formed as the core stone which was deep weathered moved along slope during the periglacial era and the matrix was removed after post-glacial era. The movements of blocks are assumed to be caused by solifluction process. The joint area where granite and andesite areas meet, granite is located beneath andesite area, and this implies that blocks were actively freezing and creeping by solifluction and freezing and thawing at that time. It can be assumes that the granite matrix formed plain slope and then andesite boulder covered up the slope. Currently, the blocks in the stony slopes of Mt. Mudeung shows almost no mobility and the stony slopes created under periglacial climate can be considered to be fossil landform.

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Potential as a Geological Field Course of the Northwest Coast, Goheung Gun (고흥군 북서 해안의 지질학습장으로서의 활용가능성)

  • Kim, Hai-Gyoung
    • Journal of the Korean Society of Earth Science Education
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    • v.9 no.2
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    • pp.163-172
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    • 2016
  • The aim of this study is to investigate the geological features distributed in the northwest coast, Goheung Gun as a geological field course of all levels. The study area is about 1.6km coast in direction of northwest from Sumundong ferry to Jangsun beach. The learning contents of the geology units in science textbooks from elementary school to high school was analyzed and, geomorphology and geology of study area was investigated for this study. In this study area, lots of geomorphology and geology elements related to the learning contents of the geology units in science textbooks were founded such as gravel beach, sea cliff, granite, rhyolite, andesite, gneiss, sedimentary rocks, fault, unconformity, stratification, cross bedding, graded bedding, intrusion structure, vein, dyke, plant fossil and spheroidal weathering. Characteristically, strata, stratification, granite, sedimentary rocks(conglomerate, sandstone, mudstone and shale), fault, plant fossil and weathering phenomenon were commonly involved with the learning contents of the geology units in elementary school science, middle school science and high school earth science I, II. This area is to be recommended as a site of geological field course for all students from elementary school to high school, as various field work materials for geological learning were distributed and, geological observation trail of about 400m in length for observation of strata and so on was installed along the coast in direction of the northwest from Sumundong ferry.

Preservation and Utilitization of Uninhabited Islets in Busan Metropolitan City (부산광역시 해안 무인도서의 보전(保全)과 활용)

  • Kim, Hang-Muk;Yu, Je-U
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2009.06a
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    • pp.475-486
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    • 2009
  • The geological survey of the Mokdo island is for the fist time conduted in Korea history. The island had erupted before $70{\sim}80$ million years as a strato-volcano. The original volcano had been dissected for long periods up to the skeletal stage through the planeze stage. If the island area is surveyed afterwrds in detail, the position of crater is available to be found, either. The coastal terrace is found at 50m level in Mokdo island which is correlated to its fourth plane. The microgeomorphological features as coastal terrace, cliff, sea cave, wave-cut bench, sea stacks, notch, and tafoni, etc. were described. The Mogdo island is located off Molundae at the extension of Nagdong Jeongmaeg(낙동정맥 洛東正脈) showing a "floating turtle". The name of Mogdo island is needed to change to the "Yoo-goo-do" which means the swimming turtle. The Mokdo island is as suitable tourist attraction for if has enough touism sesouccesein sea. The deuelopsment of coartal sightseeing anound lighthoure and uninhabited islands will hare an impontant effect upon construction of the oceanic capitol city of Busan Haabor. The master plan built up an arboretum on the island, a coastal oceanarium, a seaweeds garden under sea coast, and other oceanic culture-spaces is completed in the study.

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The Characteristics of Natural Landscape of Gaesung as Reflected in the Geographical Names (지명 속에 나타난 북한 개성시의 자연경관특성)

  • Lee Young-Hee
    • Journal of the Korean Geographical Society
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    • v.41 no.3 s.114
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    • pp.283-300
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    • 2006
  • Gaesung city of North Korea is meaningful because of the development of Gaesung industrial complex as a peace-building project and economical cooperation works between South Korea and North Korea. This article presents the characteristics of natural landscape of Gaesung through geographical names. This research was studied by literature analysis of North Korea, depth interview of North Korean labour and refugees, and second times fieldwork. The main results of this study are as follows. Firstly, the mountain landscape of Geasung revealed on geographical names characterized mountainousness and round shape. Especially, the places where are enclosed by mountain and streams are foggy and rocky. Next the landscape of stream characterizes sandy, unstable, and tidal river. Thirdly the fauna and flora which are reflected on geographical names are hawk, snake, tiger, homed owl, snapping turtle, chestnut tree, pine tree, pear tree, zelkova tree, and willow etcetera. The environmental conditions of habitation of these are similar to the natural environment of Gaesung. Besides, the geographical names related to soil distributed in northern mountain area of Geasung. The place names implicated cliff located on the riverside. In addition to this, the geographical name of 'Bul' implicated plain distributed in the riverside of 'Seoam' which a branch stream of 'Sacheo'. And the place names related rock located in place enclosed by mountain, river, and village. In cnclusion, Gaesung is more important to us as the Gaesung industrial complex and tourism development. But the fundamental research on Gaesung is a few because Gaesung belongs to North Korea. Therefore, this research will be useful for the control and management of Gaesung in the future.

Chemical weathering in King George Island, Antarctica

  • Jeong, Gi-Young
    • Proceedings of the Mineralogical Society of Korea Conference
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    • 2003.05a
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    • pp.66-66
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    • 2003
  • King George island, Antarctica, is mostly covered by ice sheet and glaciers, but the land area is focally exposed for several thousand years after deglaciation. For a mineralogical study of chemical weathering in the polar environment, glacial debris was sampled at the well-developed patterned ground which was formed by long periglaclal process. As fresh equivalents, recently exposed tills were sampled at the base of ice cliff of outlet glaciers and at the melting margin of ice cap together with fresh bedrock samples. Fresh tills are mostly composed of quartz, plagioclase, chlorite, and illite, but those derived from hydrothermal alteration zone contain smectite and illite-smectite. In bedrocks, chlorite was the major clay minerals in most samples with minor illite near hydrothermal alteration zone and interstratified chlorite-smectite in some samples. Smectite closely associated with eolian volcanic glass was assigned to alteration in their source region. Blocks with rough surface due to chemical disintegration showed weathering rinds of several millimeter thick. Comparision between inner fresh and outer altered zones did not show notable change in clay mineralogy except dissolution of calcite and some plagioclase. Most significant weathering was observed in the biotite flakes, eolian volcanic glass, sulfides, and carbonates in the debris. Biotite flakes derived from granodiorite were altered to hydrobiotite and vermiculite of yellow brown color. Minor epitactic kaolinite and gibbsite were formed in the cleaved flakes of weathered biotite. Pyrite was replaced by iron oxides. Calcite was congruently dissolved. Volcanic glass of basaltic andesite composition showed alteration rim of several micrometer thick or completely dissolved leaving mesh of plagioclase laths. In the alteration rim, Si, Na, Mg, and Ca were depleted, whereas Al, Ti, and Fe were relatively enriched. Mineralization of lichen and moss debris is of much interest. They are rich of A3 and Si roughly in the ratio of 2:1 to 3:1 typical of allophane. In some case, Fe and Ti are enriched in addition to Al and Si. Transmission electron microscopy of the samples rich of volcanic glass showed abundant amorphous aluminosilicates, which are interpreted as allophane. Chemical weathering in the King George Island is dominated by the leaching of primary phyllosilicates, carbonates, eolian volcanic glass, and minor sulfides. Authigenesls of clay minerals is less active. Absence of a positive evidence of significant authigenic smectite formation suggests that its contribution to the clay mineralogy of marine sediments are doubtful even near the maritime Antarctica undergoing a more rapid and intenser chemical weathering under more humid and milder climate.

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A study on the bedrock erosional forms at Dutayeon, Yanggu (양구 두타연 인근 지역의 기반암 하상지형 연구)

  • KIM, Jong Yeon;KIM, Chang Hwan
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.2
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    • pp.31-49
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    • 2012
  • Satae cheon, a tributary of the Suip cheon in Yanggu, Gangwon province, is an international river extended to North Korea. Most of drainage basin area of the river was the fierce battle field during the Korean War(1950-1953) and hard to access as it located between the MDL(Military Demarcation Line) and the CCZ(Civilian Control Zone: about 10km south from MDL). By the restriction of access to the sites, most of natural landscape have been well conserved except limited use for military activities. Even the landfoms in that area were not studied, except the government's heritage reports. Satae Cheon's channel follows the Imdang fault line(N-S) to Satae-ri and flow to west to the Dutayeon area. The river meanders along geological structure or weak line at the Dutayeon area. The meandering channel was shorten by the meander cut which linked the thalweg line of meander loop ant the meander neck. As a result of this cut, the river cliff formed by the Satae cheon became the part of newly formed channel bed and the S-forms are formed. After the channel route stabilized, channel incised the rock with large potholes and undulating walls were formed. The channel width changes from 1m to 10m with restriction of the undulating walls, so this part can be regarded as inner channel or inner gorge. From the point of planar forms it also can be slot-type canyon.

A Feasibility Study of Autonomous Driving and Unmanned Technology of Self-Propelled Artillery, K-9 (K-9자주포의 자율주행 및 자주포 무인화 기술의 타당성 검토)

  • Koo, Keon-Woo;Yun, Dong-Ho
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.5
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    • pp.889-898
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    • 2021
  • Currently, due to the demographic cliff phenomenon in Republic of Korea, A serious defense vacuum could occur due to the lack of South Korean military's personal strength. As a result, The South Korean military has a possibility to implement the polices the prepare for military provocations and preemptive strikes by the North Korean military while resolving the South Korean defense vacuum caused by the shrinking population. It seems like that the only way for the South Korean military to solve the shortage of personal strength due to the population decline is to reduce the number of Mechanized Units(MU) other than, infantry and automate, and autonomous driving the weapons system of the Mechanized Units(MU). In this paper, we propose the use of the virtual autonomous driving of the self propelled artillery K-9's in self selection of the position and occupation of position and self positioning in the position. At the same time in this paper, the self propelled artillery K-9 model robot is used to simulate and the explain about the operation method, necessity and feasibility in the self propelled artillery K-9. In addition, this paper predicted the problems that would arise if the South Korean military deployed autonomous driving self propelled K-9, in real combat.