• Title/Summary/Keyword: earth and man

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The physical geography in general:yesterday and tomorrow (자연지리학 일반: 회고와 전망)

  • Son, Ill
    • Journal of the Korean Geographical Society
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    • v.31 no.2
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    • pp.138-159
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    • 1996
  • There has been a tendency for Geomorphology and Climatology to be dominant in Physical Geography for 50 years in Korea. Physical Geography is concerned with the study of the totality of natural environment through the integrated approaches. But, an overall direction or a certain paradigm could not be found, because major sub-divisions of Physical Geography have been studied individually and the subjects and the approaches in studying Physical Geography are enormously diverse. A consensus of opinion could not also exist in deciding what kind of the sub-divisions should be included in the physical geography in general and how those should be summarized. Furthermore it would be considered imprudent to survey the studies of Physical Geography besides those of Geomorphology and Climatology due to the small number of researchers. Assuming that the rest of Physical Geographical studies with the exception of Geomorphological and Climatological studies are the Physical Geography in general, the studies of Physical Geogrpahy in general are summarized and several aspects are drown out as follows. First the descliption of all possible factors of natural environments was the pattern of early studies of Physical Geography and the tendency is maintained in the various kinds of research and project reports. Recently Physical Geographers have published several introductory textbooks or research monographs. In those books, however, the integrated approaches to Physical Geography were not suggested and the relationship between man and nature are dealt with in the elementary level. Second, the authentic soil studies of Physical Geographers are insignificant, because the studies of soil in Physical Geography have been mostly considered as the subsidiary means of Geomorphology Summarizing the studies of Soil Gegraphy by physical geographers and other Pedologists, the subjects are classified as soil-forming processes, soil erosions, soil in the tidal flat and reclaimed land, and soil pollution. Physical Geographers have focused upon the soil-forming processes in order to elucidate the geomorphic processes and the past climatic environment. The results of other subjects are trifling. Thirdy Byogeygrayhers and the results of studies are extremely of small number and the studies of Biogeography in Korea lines in the starting point. But, Biogeography could be a more unifying theme for the Physical-human Geography interface, and it would be expected to play an active part in the field of environmental conservation and resource management. Forth, the studies of Hydrogeography (Geographical Hydrology) in Korea have run through the studies of water balance and the morphometric studies such as the drainage network analysis and the relations of various kinds of morphometric elements in river. Recently, the hydrological model have introduced and developed to predict the flow of sediment, discharge, and ground water. The growth of groundwater studies is worthy of close attention. Finally, the studies on environmental problems was no mole than the general description about environmental destruction, resource development, environmental conservation, etc. until 1970s. The ecological perspectives on the relationship between man and nature were suggested in some studies of natural hazard. The new environmentalism having been introduced since 1980s. Human geographers have lead the studies of Environmental Perception. Environmental Ethics, Environmental Sociology, environmental policy. The Physical geographers have stay out of phase with the climate of the time and concentrate upon the publication of introductory textbooks. Recently, several studies on the human interference and modification of natural environments have been made an attempt in the fields of Geomorphology and climatology. Summarizing the studies of Physical Geography for 50 years in Korea, the integrated approaches inherent in Physical Geography disappeared little by little and the majol sub-divisions of Physical Ceography have develop in connection with the nearby earth sciences such as Geology, Meteorology, Pedology, Biology, Hydrology, etc been rediscovered by non-geographers under the guise of environmental science. It is expected that Physical Geography would revive as the dominant subject to cope with environmental problems, rearming with the innate integrated approaches.

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A comparative study of borehole size and tool effect on dispersion curves (시추공경과 공내검층기가 분산곡선에 미치는 영향에 대한 비교 연구)

  • Zhao, Weijun;Kim, Jong-Man;Kim, Yeong-Hwa
    • Geophysics and Geophysical Exploration
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    • v.12 no.1
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    • pp.154-162
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    • 2009
  • Sonic wave dispersion characteristics are one of the most important targets of study, particularly in estimating shear wave velocity from borehole sonic logging. We have tested dispersion characteristics using monopole and dipole sources. Theoretical dispersion curves were computed for tool-absent and tool-included models having the same physical properties but different diameters (including ${\Phi}520mm$, ${\Phi}150mm$, and ${\Phi}76mm$). Comparisons were made between boreholes of different sizes and between tool-absent and tool-included models. Between the tool-included and the tool-absent boreholes, a close similarity in dispersion curve shape was revealed for the monopole source, and a significant difference was shown for the dipole source. However, for the cut-off frequency, particularly in the engineering boreholes (${\Phi}76mm$ and ${\Phi}50mm$), a significant difference was observed for signals from the monopole source, but approximately the same cut-off frequencies were found with the dipole source. This indicates the need of careful choice of source frequency in monopole-source sonic logging, particularly in an engineering borehole. The results of numerical experiments show that cut-off frequency is exponentially proportional to the inverse of borehole radius, irrespective of the mode type and the presence of a tool, and that the cut-off frequencies for each borehole environment could be expressed as an exponential function, rather than the inversely proportional relationship between the cut-off frequency and the borehole radius that was previously generally recognised. From the direct comparison of dispersion curves, the effects on the dispersion characteristics of borehole size and the presence of the tool can be revealed more clearly than in previous studies, which presented the dispersion curve and/or characteristics for each borehole environment separately.

Performance Evaluation for All-In-One Construction Method of Curbstone and Gutter Using Formwork Rail and Jig (거푸집 레일과 지그를 이용한 경계석 및 측구의 일체형 시공법에 대한 성능평가)

  • Choi, Jae-Jin;Ko, Man-Gi;Kim, Kyoung-Ju;Choi, Khyung-Dong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.6A
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    • pp.525-534
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    • 2010
  • A road curbstone is a structure installed at the boundary of the sidewalk and the street with the objectives of road drainage, drawing attention and such. The current general construction method of curbstones places foundation concrete for the curbstones first, waits until the concrete reaches the strength to support the curbstones, places the curbstones on top, and then places the gutter and rear filling concrete. Such method has the issues of poor compaction and weakened bond strength of concrete due to split placing of concrete, and causes the curbstones to easily separate due to vehicle impact or earth pressure, in turn creating maintenance costs and spoiling the aesthetics. To improve such conventional construction methods, an all-in-one method was developed using formwork rail and jig where both the curbstones and gutter can be worked at the same time, and to evaluate the structural performance, static tests of lateral loading test, pullout test, and bending test were executed, and dynamic tests such as pendulum test and actual vehicle impact test were executed. In all tests, the all-in-one construction method using formwork rail and jig was shown to be superior to the conventional construction method by the increase of construction quality and bond strength of concrete.

The Combination of Yin-Yang and Five Elements in Lu's Spring and Autumn - Focusing on the Rules of Four Seasons Thought in the Twelve principle (『여씨춘추(呂氏春秋)』에서의 음양(陰陽)과 오행(五行)의 결합(結合) - 십이기(十二紀)의 월령사상(月令思想)을 중심으로 -)

  • Cho, Jueun;Yun, Muhak
    • The Journal of Korean Philosophical History
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    • no.42
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    • pp.133-164
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    • 2014
  • In "Lu's Spring and Autumn", the ideas of all the schools before Qin Dynasty were compiled and the diagram of the Trinity of heaven, earth and man using the category of Yin-yang and the five elements of the universe since the ancient times was established. This can be assessed to be the blueprint for a unified empire closely connecting time and space, and objects in heaven and on earth centered around human beings. In specific, Yin-yang and the five elements of the universe were combined to categorize and schematize all things in the universe, and connect them to human affairs at the same time. Its contents convert almost all academic fields including politics, economics, society, military, astronomy, geography, medical science, education and history. Particularly, the documents popular during the age of civil wars and the ideas of Jikha scholars were synthesized and specified. Yet, it went beyond simple collection of the thoughts and documents since the ancient times in terms of contents and forms, and the method of 12 months for 1 year was selected and prescript was expanded to the various fields of politics and the society. In the Twelve principle, Yin-yang and the five elements, and the ten celestial stems and the earthly ones were combined, the contradiction from the process was solved, and the Rules of Four Seasons Thought was completed. Therefore, even though some parts of the idea of Yin-yang and the five elements in "Lu's Spring and Autumn" is found here and there from other documents, the unificative systematization of the whole has an important meaning in the history of thought. In summary, it has been proved that the Rules of Four Seasons Thought in "Lu's Spring and Autumn" was not limited to the physical unity of Yin-yang and the five elements of the universe, but qualitatively specified particularly in the aspects of agriculture from the people's side and politics from a leader's position.

Assessment of Biochemical Efficiency for the Reduction of Heavy Metal and Oil Contaminants in Contaminated Soils (토양내 중금속 및 유류 오염농도 저감을 위한 생화학적 기작의 효율성 평가)

  • Kim, Man-Il;Jeong, Gyo-Cheol;Kim, Eul-Young
    • The Journal of Engineering Geology
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    • v.22 no.3
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    • pp.253-262
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    • 2012
  • With the aim of remediating soils contaminated by heavy metals and oil, experimental research was conducted to evaluate the optimal design factors for remediation in terms of efficient soil washing methods and processes. The experiments employed absorptiometric analysis and gas chromatography methods to reduce the concentration of heavy metals such as cooper (Cu), lead (Pb), and zinc (Zn), and total petroleum hydrocarbons (TPH) in contaminated soils. The experimental processes consisted of deciding on the washing solution, washing time, and dilution ratio for contaminated soils. A dissolution analysis of heavy metals was then performed by the addition of surfactant, based on the results of the decision experiments, and the injection processes of microbes and hydrogen peroxide were selected. The experimental results revealed that reduction effects in contaminated soils under the experimental conditions were most efficient with hydrochloric acid 0.1 mole, washing time 1 hour, and dilution ratio 1:3, individually. Additional reduction effects for heavy metals and TPH were found with the addition of a washing solution of 1% of surfactant. The addition of microbes and hydrogen peroxide caused a reduction in TPH concentration.

Geochemistry of Heavy Metals and Rare Earth Elements in Core Sediments from the Korea Deep-Sea Environmental Study (KODES)-96 Area, Northeast Equatorial Pacific (한국심해환경연구(KODES) 지역 주상 퇴적물중 금속 및 희토류원소의 지구화학적 특성)

  • Jung, Hoi-Soo;Park, Sung-Hyun;Kim, Dong-Seon;Choi, Man-Sik;Lee, Kyeong-Young
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.2 no.2
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    • pp.125-137
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    • 1997
  • To study the vertical variation of heavy metal and Rare Earth Element (REE) contents in deep-sea sediments, eighteen cores were sampled from the Korea Deep-sea Environmental Study (KODES)-96 area in the C-C zone (Clarion-Clipperton fracture zone), northeast equatorial Pacific. Sediment columns can be divided into three units based on sediment colors and geochemical characters; uppermost Unit I with brown color, middle Unit II with pale brown color and smaller Ni/Cu ratio than the ratio in Unit I, and lowermost Unit III with dark (brown) colors and higher contents of Mn, Ni, Cu, and REEs than those in Unit I and II. Unit II can be divided more into two layers of upper Unit IIa and lower Unit IIb. Unit IIb is characterized by high contents of Cu, 3+REEs (REEs except Ce), smectite, and severely deteriorated fossil tests. Unit III can also be divided into two units; upper Unit IIIa with dark brown color, and lower Unit IIIb with black color and enriched Mn and Fe. The KODES area was located near from the East Pacific Rise (EPR) When Unit III Sediments were deposited, considering the hiatus between Unit II and III (Quaternary-Tertiary boundary) and the spreading rate (10 cm/yr) and direction (north southern west) of the Pacific plate from the EPR. High contents of Mn and Fe in Unit IIIb may be related with hydrothermal influence from the EPR. Meanwhile, Unit IIb (about 2~3 Ma) and Unit III (11~30 Ma) layers were probably formed near (or under) the equatorial high productivity zone, and accordingly received a lot of organic materials. As a result, Cu and 3+REEs, closely associated with organic materials, are enriched in smectite and/or Ca-P composites (fish bone debrise, biogenic apatite) after decomposition and reprecipitation on the sea floor. Higher contents of Cu and 3+REEs in Unit IIb and III are suggested to be the result of abundant supply of organic substances in the equatorial high productivity zone.

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Development and Preliminary Performance Analysis of a fast and high precision Tracking Mount for 1m Satellite Laser Ranging (1m급 인공위성 레이저추적 시스템용 고속·고정밀 추적마운트 개발 및 예비 성능분석)

  • Choi, Man-Soo;Lim, Hyung-Chul;Lee, Sang-Jung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.11
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    • pp.1006-1015
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    • 2016
  • This paper presents preliminary design and performance analysis of a fast and high precision Tracking Mount for 1m Satellite Laser Ranging(SLR) which is development by Korea Astronomy and Space science Institute(KASI). SLR is considered to be the most accurate technique currently available for the precise orbit determination of Earth satellites. The SLR technique measures the time of flight between pulses emitted from laser transmitter and pulses returned from satellites with laser retro-reflector array. It provides millimeter level precision of range measurements between SLR stations and satellites. A fast and high precision Tracking Mount for SLR which is proposed in this research should be capable of day and nighttime laser tracking about the satellites with laser reflectors from 200 km to 36,000 km altitude(geosynchronous orbit). In order to meet this requirement, we performed mechanical design and structural analysis for Tracking Mount. Also we designed the motion control system and conducted pre-performance analysis to obtain good performance results for a fast and high precision Tracking Mount.

Study on Rainfall infiltration Characteristics for Weathered Soils: Analysis of Soil Volumetric Water Content and Its Application (국내 풍화토의 강우 침투특성 분석을 위한 실험연구: 토양 체적함수비 분석 및 적용성 평가)

  • Kim, Man-Il;Chae, Byung-Gon;Cho, Yong-Chan;Seo, Yong-Seok
    • The Journal of Engineering Geology
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    • v.18 no.1
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    • pp.83-92
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    • 2008
  • In order to analyze infiltration characteristics of rainfall in soil, two laboratory experiments were conducted using an amplitude domain reflectometry (ADR) sensor and a pore water pressure meter (PWP) in this study. The first experiment is to understand the dependency of volumetric water content and temperature for standard sand and weathered granite soil. The second experiment is a laboratory flume test with changes of rainfall condition. As the results of the dependency experiment, the volumetric water content is increased with increase of the output voltage measured by the ADR sensor in both the standard sands and weathered granite soil. Furthermore, the results also indicate necessity of consideration of the temperature dependency under the condition of high volumetric water contents from 0.15 to 0.45. In the flume test, two measurement devices are detected to the variation of volumetric water content and pore water pressure at the installation point of the flume. In especial, the measured values of ADR4 and PWP3 installed on the lower part of slope are higher than those of the others. It means that the lower part of slope plays a role of a runoff face and a beginning point of slope failure.

고대(古代) Egypt 복식(服飾)에 나타난 상징성(象徵性) - Tutankhamen 왕조(王朝)를 중심으로 -

  • Jeong, Heung-Suk
    • Journal of the Korean Society of Costume
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    • v.6
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    • pp.121-143
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    • 1982
  • Many studies have done on Egyptian Clothing because its unique characteristic culture. However, I was facinated by the exhibitions of Tutankhamen burial treasures which were shown in San Francisco and New York in 1978 and 1979. I found out myself that there are several interesting aspects of clothing to compare 18th dynasty king, Tutankhamun and other dynasties in Egyptian culture. Therefore, I tryed to analized the Egyptian clothing including accessaries with theigr symbols durin 18th dynasty King, Tutankhamun. The most of people were shocked and amazed when they toured the exhibition of Tutankhamun articles which were the most incredible burial treasures in existence today. The body of the King has been embalmed, bandaged and fitted in eight layers of coffins with pure gold mask to represent the god Osiris. Among eight layers of coffins, one is pure solid gold in mummiform, two of mummiforms are made of compact wood covered with sheets of gold and inlaid with multi-colored glass-paste and semi-precious stones. The Egyptian belived that the soul continued to exist throughout eternity if it had passed on examination of its deeds on earth at a "Last Judgement" presided over by Osiris. They also believed that the mummified body could exist in the tomb as a habitation that the soul could revisited. Thus a proper burial was vital for a full existence in the hereafter. They buried dead person in the sealed vault of the tomb with some of the possessions he had used during his life time, such as his furniture, clothing and jewels. In this studies, I've tried to research to various clothings, and accessories with their symbols used during 18th dynasty king, Tutankhamun. The studies are shown as: I) Clothings of Tutankhamun dynasity of Kalasiris, Sheath skirt. Gala skirt, Loin skirt, Hike and Dalmatic. The Dalmatic was first seen in this dynasty. Probably the Roman Christian borrowed the Dalmatica from Egyptian Dalmatic. No where has the same design at the period. II) Egyptian of 18th dynasty Tutankhamun wore big headdress, broad collar necklace passium, pendants, armlets, rings and earrings with very beautiful, exquisite handcraft. They seem the first people who wore earrings in Egyptian history. III) The symbols of decorated items vulture, lotus...Upper Egypt Uraeus, papyrus...Lower Egypt scaravaeus, Nile Riber...rebirth man(Ankh), +...eternal life solar disc, gold...sun ostrich-feather...nobleness God, Horus' eye...protection against enemy IV) Also Egyptian prefered the straight line and a right angle which were the basic principles of architectural arrangement.

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Coastal Current Along the Eastern Boundary of the Yellow Sea in Summer: Numerical Simulations (여름철 황해 동부 연안을 따라 흐르는 연안 경계류: 수치 모델 실험)

  • Kwon, Kyung-Man;Choi, Byoung-Ju;Lee, Sang-Ho;Cho, Yang-Ki;Jang, Chan-Joo
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.4
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    • pp.155-168
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    • 2011
  • Coastal boundary current flows along the eastern boundary of the Yellow Sea and its speed was about 0.l m/s during the summer 2007. In order to find major factors that affect the coastal boundary current in the eastern Yellow Sea, three-dimensional numerical model experiments were performed. The model simulation results were validated against hydrographic and current meter data in the eastern Yellow Sea. The eastern boundary current flows along the bottom front over the upper part of slopping bottom. Strength and position of the current were affected by tides, winds, local river discharge, and solar radiation. Tidal stirring and surface wind mixing were major factors that control the summertime boundary currents along the bottom front. Tidal stirring was essential to generate the bottom temperature front and boundary current. Wind mixing made the boundary current wider and augmented its north-ward transport. Buoyancy forcing from the freshwater input and solar radiation also affected the boundary current but their contributions were minor. Strong (weak) tidal mixing during spring (neap) tides made the northward transport larger (smaller) in the numerical simulations. But offshore position of the eastern boundary current's major axis was not apparently changed by the spring-neap cycle in the mid-eastern Yellow Sea due to strong summer stratification. The mean position of coastal boundary current varied due to variations in the level of wind mixing.