• Title/Summary/Keyword: Ground source

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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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Leak Location Detection of Underground Water Pipes using Acoustic Emission and Acceleration Signals (음향방출 및 가속도 신호를 이용한 지하매설 상수도배관의 누수지점 탐지연구)

  • Lee, Young-Sup;Yoon, Dong-Jin;Jeong, Jung-Chae
    • Journal of the Korean Society for Nondestructive Testing
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    • v.23 no.3
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    • pp.227-236
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    • 2003
  • Leaks in underground pipelines can cause social, environmental and economical problems. One of relevant countermeasures against leaks is to find and repair of leak points of the pipes. Leak noise is a good source to identify the location of leak points of the pipelines. Although there have been several methods to detect the leak location with leak noise, such as listening rods, hydrophones or ground microphones, they have not been so efficient tools. In this paper, acoustic emission (AE) sensors and accelermeters are used to detect leak locations which could provide all easier and move efficient method. Filtering, signal processing and algorithm of raw input data from sensors for the detection of leak location are described. A 120m-long pipeline system for experiment is installed and the results with the system show that the algorithm with the AE sensors and accelerometers offers accurate pinpointing of leaks. Theoretical analysis of sound wave propagation speed of water in underground pipes, which is critically important in leak locating, is also described.

3dimension Topography Generation and Accuracy Analysis Using GIS (GIS를 이용한 3차원 지형도 생성 및 정확도 분석)

  • Nim Young Bin;Park Chang suk;Lee Cheol Hee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.2
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    • pp.189-196
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    • 2005
  • Recently as map making skills developed and as digital maps prevailed, peoples began to take interest in the realistic 3dimension topography rather than the flat 2 dimension one. The experiment is done by using the topographical information from the digital maps, To analyze the preciseness of this 3dimension topography, analysis of the coordinate-changed standard map image and the location errors of the plane and height from digital values of the map's topography by layers and features, were done. The visual results of locational values differed by every programs of coordinate transformation. Errors of locations also appeared from the methods of correcting the visual sources, when deciding the standard source's datum point. The plan's accuracy of the image data coordinate transformation is about ${\pm}4.1m$. In ground distance, therefore, it is included in the allowed error of the 1:25,000 scale changed map, satisfying the plan's accuracy. Also, by the use of reasonably spaced grid, it satisfied the visual topographical accuracy. Because the 3 dimension topographical map can be produced effectively and rapidly by using various scale's standard map image and the digital map, the further practical use of 3 dimension topographic map made by using the existing topographies and changed maps has high expectations.

Remote Sensing of Atmospheric Trace Species using Multi Axis Differential Optical Absorption Spectroscopy (Multi Axis DOAS를 이용한 대기미량 물질 원격 측정)

  • Lee Chul-Kyu;Kim Young-Joon
    • Korean Journal of Remote Sensing
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    • v.22 no.2
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    • pp.141-151
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    • 2006
  • UV-visible absorption measurement techniques using several horizone viewing directions in addition to the traditional zenith-sky pointing have been recently developed in ground-based remote sensing of atmospheric constituents. The spatial distribution of various trace gases close to the instrument can be derived by combing several viewing directions. Multi-axis differential optical absorption spectroscopy (MAX-DOAS) technique, one of the remote sensing techniques for air quality measurements, uses the scattered sunlight as a light source and measures it at various elevation angles (corresponding to the viewing directions) by sequential scanning with a stepper motor. A MAX-DOAS system developed by GIST/ADEMRC has been applied to measuring trace gases in urban air and plumes of the volcano and fossil fuel power plant in January, May, and October 2004, respectively. MAX-DOAS spectra were analyzed to identify and quantify $SO_2,\;NO_2,\;BrO,\;and\;O_4$ (based on Slant Column Densities, SCD) in the urban air, volcanic plume, and fossil fuel power plant utilizing theirs specific structured absorption features in the UV-visible region. Vertical scan through the multiple elevation angles was performed at different directions perpendicular to the plume dispersion to retrieve cross-sectional distribution of $SO_2\;or\;NO_2$ in the plumes of the volcano and fossil fuel power plant. Based on the estimated cross sections of the plumes the mixing ratios were estimated to 580 $SO_2$ ppbv in the volcanic Plume, and 337 $NO_2\;and\;227\;SO_2$ ppbv in the plume of the fossil fuel power plant, respectively.

A Study on the Aristotle's Eudaimonia (아리스토텔레스의 에우다이모니아 개념에 관한 연구)

  • Park, Sung-ho
    • Journal of Korean Philosophical Society
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    • v.141
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    • pp.63-84
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    • 2017
  • In the twentieth century Anscombe's 1958 article "Modern Moral Philosophy" argued that duty-based conceptions of morality are conceptually incoherent for they are based on the idea of a "law without a lawgiver". Concepts such as "morally ought", "morally obligated", and "morally right" require a legislator as the source of moral authority. In the past God occupied the role, but systems that dispense with God are lacking the proper foundation for meaningful employment of those concepts. Aristotle's virtue ethics can do so without appealing to any such lawgiver, and ground morality in the well being of human moral agents. Therefore Anscombe recommends a return to the eudaimonistic ethical theories of the ancients as secular approaches. Eudaimonia is a central concept in Aristotelian ethics, along with the terms "aret?"(translated as virtue or excellence) and "phronesis"(translated as practical wisdom). In Aristotle's works, eudaimonia was used as the term for the highest human good, and so it is the aim of practical philosophy to consider what it really is and how it can be achieved. Eudaimonia is a Greek word commonly translated as well-being, happiness, welfare or "human flourishing". As Aristotle points out, saying that eudaimon life is a life which is objectively desirable, and means living well. Everyone wants to be eudaimon. And everyone agrees that being eudaimon is related to faring well and to an individual's well being. But the really difficult question is to specify just what sort of activities enable one to live well. Aristotle says that the eudaimon life is one of "virtuous activity in accordance with reason," this is a necessary condition of eudaimonia, the pleasure accompanied by virtuous activities is a sufficient condition. Hence we have a more accurate translation of eudaimonia with a review the practical meaning of eudaimonia, and the correlation between eudaimonia and arete, pleasure.

Flow Characteristics and Wind Loads on the Solar Panel and Floating System of Floating Solar Generato (부유식 태양광 발전기의 패널과 부유체에 작용하는 풍하중과 유동특성)

  • Ryu, Dae-Gyeom;Lee, Kye-Bock
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.10
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    • pp.229-235
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    • 2019
  • A floating photovoltaic generation system is a new concept that combines existing photovoltaic generation technology with floating technology. This is installed in the water not on conventional land and a building. The system is designed as a unit module type that can be connected to other modules according to the power generation capacity, thereby forming a large-scale power generation facility. As a renewable energy source, it is composed of a floating structure, mooring device, photovoltaic power generation facility, and underwater cable. Because this system is installed outdoors, the effect of the wind load on the structure is very large. In this study, the wind loads most affected on the floating photovoltaic generation structure were obtained by computational fluid dynamic analysis. The flow characteristics and wind loads were analyzed for a range of wind orientations and angles of inclination. The analysis showed the position and magnitude of the maximum wind load to the wind direction and the flow characteristics around the solar panel and floating system. The wind load increased with increasing angle of inclination of the panel to the ground.

A Study on the Education of the Fisheries School of Korea in Japanese Colony (일제하의 수산학교 교육에 관한 연구)

  • Shin, Qui-Won;Kim, Sam-Kon;Chi, Ho-Weon;Kim, Jae-Sik;Kim, Tae-Wun
    • Journal of Fisheries and Marine Sciences Education
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    • v.11 no.1
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    • pp.69-87
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    • 1999
  • This study had been analysed the establishment, the closing and the actual conditions of the fisheries school according to the four times revision and promulgation of the law of education of korea which were devided by the early term (the first Chosun educational decree), the middle term (the second Chosun educational decree) and the last term (the third and fourth Chosun educational decree), and also been investigated how the fisheries education of the school had been acted to the mobocracy and the assimilation policy and together with it's back ground through this analysis. The aim of this study is to contribute to the study of the history of the fisheries school education, analysis of change of the fisheries school education according to practical application of the Chosun educational decree. The summary of the characteristic of the each term are as under. First, in the early term of the fisheries education under the first Chosun educational decree, Experts were despatched to the each province with donated money from emperor and opened seasonal the fishing training centre, a kind of social fisheries education, and trained directly fishing technic and were going to train fisheries trainees regularly under name of elementary fisheries school. Japanese imperialism attached great importance to the vocational education in order to snack economical products from colonized Korea but actually had a purpose to train low quality technician who follow blindly their colony policy of Japanese imperialism. The fisheries schools in the circle of system in early time of Japanese imperialism, Kunsan public elementary fisheries school was established in April 1915, Yosu public elementary fisheries school was established ill May 1917 and Kyungnam Tongyoung training school was established in March 1917. Secondly, After 3.1 movement, the Japanese imperialism established an appeasement policy so called cultural politics and continued assimilation policy with skilful methods. After revision of the second Chosun educational decree, the Elementary vocational school was changed as the vocational training school. The school of fisheries education in middle of Japanese imperialism trained low quality technicians to snack fisheries resources from colonized Korea. After the middle of Japanese imperialism they paid attention on training fisheries technician through fisheries school rather than training school. With high interest and crowded volunteers, Kunsan public fisheries school was promoted in 1922, Tongyoung public fisheries school was promoted in 1923, Yongampo fisheries training school established in 1922 was promoted as Yongampo public fisheries school in 1926. Thirdly, in the time of the third and fourth Chosun educational decree, the end of Japanese imperialism, they met Pacific war after Japan vs China war. During the war time they considered the vocational school as the source of supply for materials and manpower and consequently had to expanded vocational education and systematically despatched students to war field and practiced military training. In 1938, Namhae public fisheries school was established and Chungjin fisheries school was permitted. But in order to supply manpower to Pacific war, the study period of Yosu public fisheries school was shorten from 5 years to 4 year in 1943 and also that of Tongyoung public fisheries school shorten in 1944.

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Design of Performance Monitoring System for eLoran Time Synchronization Service (eLoran 시각동기 성능 모니터링 시스템 설계)

  • Seo, Kiyeol;Son, Pyo-Woong;Han, Younghoon;Park, Sang-Hyun;Lee, Jong-Cheol
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.6
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    • pp.815-821
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    • 2021
  • This study addresses on the design of performance monitoring system for the time synchronization service of the enhanced long-range navigation (eLoran) system, which has a representative ground-wave radio broadcast system capable of providing positioning, navigation, timing and data (PNT&D) services. The limitations of time-synchronized systems due to the signal vulnerabilities of the global navigation satellite system (GNSS) are explained, and the performance monitoring system for the eLoran timing service as a backup to the GNSS is proposed. The time synchronization service using eLoran system as well as system configurations and the user requirements in the differential Loran (dLoran) system are described to monitor the time synchronization performance. The results of the designed system are presented for long-term operation in the eLoran testbed environment. As the results of time performance monitoring, we were able to verify the time synchronization precision within 43.71 ns without corrections, 22.52 ns with corrections. Based on these results, the eLoran system can be utilized as a precise time synchronization source for GPS timing backup.

A Comparative Study on Marine Transport Contract and Marine Insurance Contract with Reference to Unseaworthiness

  • Pak, Jee-Moon
    • Journal of Korea Trade
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    • v.25 no.2
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    • pp.152-177
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    • 2021
  • Purpose - This study analyses the excepted requirement and burden of proof of the carrier due to unseaworthiness through comparison between the marine transport contract and marine insurance contract. Design/methodology - This study uses the legal analytical normative approach. The juridical approach involves reviewing and examining theories, concepts, legal doctrines and legislation that are related to the problems. In this study a literature analysis using academic literature and internet data is conducted. Findings - The burden of proof in case of seaworthiness should be based on presumed fault, not proved fault. The burden of proving unseaworthiness/seaworthiness should shift to the carrier, and should be exercised before seeking the protections of the law or carriage contract. In other words, the insurer cannot escape coverage for unfitness of a vessel which arises while the vessel is at sea, which the assured could not have prevented in the exercise of due diligence. The insurer bears the burden of proving unseaworthiness. The warranty of seaworthiness is implied in hull, but not protection and indemnity policies. The 2015 Act repeals ss. 33(3) and 34 of MIA 1906. Otherwise the provisions of the MIA 1906 remain in force, including the definition of a promissory warranty and the recognition of implied warranties. There is less clarity about the position when the source of the loss occurs before the breach of warranty but the actual loss is suffered after the breach. Nonetheless, by s.10(2) of the 2015 Act the insurer appears not to be liable for any loss occurring after the breach of warranty and before there has been a remedy. Originality/value - When unseaworthiness is identified after the sailing of the vessel, mere acceptance of the ship does not mean the party waives any claims for damages or the right to terminate the contract, provided that failure to comply with the contractual obligations is of critical importance. The burden of proof with regards to loss of damage to a cargo caused by unseaworthiness is regulated by the applicable law. For instance, under the common law, if the cargo claimant alleges that the loss or damage has been caused by unseaworthiness, then he has the burden of proof to establish the followings: (i) that the vessel was unseaworthy at the beginning of the voyage; and that, (ii) that the loss or damage has been caused by such unseaworthiness. In other words, if the warranty of seaworthiness at the inception of the voyage is breached, the breach voids the policy if the ship owner had prior knowledge of the unseaworthy condition. By contrast, knowingly permitting the vessel to break ground in an unseaworthy condition denies liability only for loss or damage proximately caused by the unseaworthiness. Such a breach does not, therefore, void the entire policy, but only serves to exonerate the insurer for loss or damage proximately caused by the unseaworthy condition.

Evaluation of Fire Investigation as the Separation Distances for Several Types of Insulation Panels (단열패널 종류별 이격거리에 따른 화재감식 평가)

  • Kim, Jeong-Hun;Kim, Da-Seul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.4
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    • pp.403-412
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    • 2021
  • Despite strengthening requirements for fire retardancy and applied buildings of insulation panels, the number of fires and influence of damage have increased. In this study, the thermal effects were evaluated as the separation distances, and three types of EPS panel, glass wool panel, and gypsum board panel were then selected. Temperature sensors on the panels were installed vertically from the ground. The fire source on the lamination layer of lumber was ignited by changes in the separation distances (0 cm, 25 cm, 50 cm) from the panels. The test results suggested that the maximum temperature was 349 ℃ in the EPS panel. The inside/outside shape changes were limited by the height of the low and middle positions until the critical point of a 25 cm separation distance. Furthermore, the combustion marks appeared after 500 s on average, and then the EPS panel with a high fire strength showed a broad "U type" pattern, glass wool panel, and gypsum board panel showed medium or narrow "V type" pattern. Therefore, the acquired data can provide valuable information for evaluating the fire risks and verifying fire investigation from buildings composed of these insulation panels.