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Installation and Vegetation Management for Enhanced Authenticity of Jeju Ohyundan (제주 오현단의 진정성 제고를 위한 시설 및 식생관리)

  • Rho, Jae-Hyun;Oh, Hyun-Kyung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.3
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    • pp.25-37
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    • 2013
  • The purpose of this study is to draw reasonable management plans to reinforce essence of Ohyundan(五賢壇: Five sprit tablets), a sacred site and monument of Jeju, by investigating and analyzing current status and problems of cultural landscape elements(e.g. architectural structures, installation, letters carved on the rocks, actual vegetation, etc.) while grasping placeness contained in Ohyundan through consideration of its history and transition process of Ohyundan a future being and shrine of Gyulrim Seowon(橘林書院) in Jeju. Results derived from research are summarized as follows. Ohyundan is noted due to its placeness in that it was a place for Gyulrim Seowon, Jeju's one and only Saaek Seowon(賜額書 院) and it was a symbolic space of exile culture in Jeju. As it is inferred from Gyulrim Seowon, which is dangho(堂號: clan name) of Seowon, orchards surrounding all over places are a signature landscape element that shows placeness of the past Ohyundan. Joduseok(俎豆石: altar stone), representing a core installation of Ohyundan and ancestral tablet of five spirits, created a refined place by putting up common stones around altar and founding blocked stones to wall. This refinement and thrift served basic mind of Neo-Confucianism, and led to of Jeju's Jonyang mind(spend-thrift mind). In conclusion, a practice plan is a prerequisite to restore essence of Ohyundan by actively excluding installations not suitable for placeness or overly designed such as Jeju Hyangrodang(a center for the elderly) and numerous monument houses. On the other hand, together with Joduseok, as letters carved on the rocks such as 'Jeungjoo Byukrip(曾朱壁立)' and 'Gwangpoongdae(光風臺)' and Yoocheonseok serve as a signature landscape that well shows mind of five spirits and teaching of Neo-Confucianism, and also a trace from a confucian viewpoint deeply rooted in Jeju, they are judged as a cultural landscape corresponding to the essence of place in Ohyundan which requires proactive preservation and plans for public relations. Together with this, although many different old big trees such as Pinus densiflora , Pinus thunbergii, Quercus variabilis, Celtis sinenis, Zelkova serrata and Rhus succedanea are a landscape element that increases sacred Ohyundan and commemorative value, now required is thorough entity tree management by assigning serial number on them as many of them were dead or removed resulting from transition process of land use. Further, to reinforce quality of site location belonging to Gyulrim Seowon, a prerequsite is to review plans that create Gyulrim at reinstalled site of building and raw land.

Petrochemistry of Garnet-bearing Metabasite in Marble at Shinri area in Hongseong and its Tectonic Implication (홍성 신리 지역 대리암 내 함석류석 변성염기성암의 암석지화학 연구 및 그 지구조적 의미)

  • Kim, Sung-Won;Koh, Hee-Jae
    • The Journal of the Petrological Society of Korea
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    • v.19 no.3
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    • pp.209-225
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    • 2010
  • The Shinri area near the Yedang Lake, the eastern part of the Hongseong area in SW Gyeonggi Massif, consists of the Neoproterozoic Duckjeongri granodiorite-tonalite, mylonitized amphibole-bearing orthogneiss and impure marble with lens-shaped garnet-bearing metabasites. In this paper, we report mineralogical and geochemical data of Neoproterozoic lens-shaped garnet-bearing metabasites within marble of the Shinri area. The $SiO_2$ contents of garnet-bearing metabasites in marble vary between ~46.98 and 51.17 wt%, and the $Na_2O$ + $K_2O$ contents fall between ~1.95 and 2.85 wt%, similar to the tholeiitic sub-alkaline basaltic rocks. In the Zr/Y vs. Zr diagram, garnet-bearing metabasites also plot in the subalkaline basaltic rocks. The chondrite-normalized REE patterns for Shinri garnet-bearing metabasites show relatively flat patterns to that of chondrite. They show slight LREE-enriched and depleted patterns. The major and trace element data from lens-shaped garnet-bearing metabasites in marble of the Shinri area suggest that these rocks were formed in within plate. In contrast, previous major and trace element data of high pressure type garnet-bearing metabasites from the mafic-ultramafic complex in the Baekdong and Bibong areas suggest that these rocks were formed in a nascent arc to backarc spreading center within subduction zone setting. Based on mineral assemblage and mineral chemistry, P-T estimates for Shinri garnet-bearing metabasites are 9.6-12.7 kb, $695-840^{\circ}C$ for inclusions in the core, and 9.6-13.6 kb, $630-755^{\circ}C$ for those in the rim. These P-T estimates are distinct from those of the Baekdong and Bibong garnet-bearing metabasites with isothermal decompressional retrograde P-T path. In addition to Triassic tectonic activity previously reported in the Shinri area of Hongseong, the details of metamorphic history such as protolith age and Neo-Proterozoic metamorphic episode need to be solved.

Rate of Sediment Accumulation and Geochemical Characteristics of Muddy Sediment in the Central Yellow Sea (황해 중앙부 해역 니질 퇴적물의 지화학적 특성 및 퇴적률)

  • 윤정수;김여상
    • The Korean Journal of Quaternary Research
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    • v.16 no.1
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    • pp.1-16
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    • 2002
  • A total of 4 muddy sediment samples collected from the Central Yellow Sea were analyzed for chemical composition. The results are compared with the previously published Huanghe, Changjiang and Keum River geochemical data in order to understand provenance and sedimentation of fine-grained mud, and the sediment accumulation rates estimated. The sandy sediment facies is distributed in the eastern area, a patch of fine-grained mud exists in the western central prat, and the sandy mud and clay sedimentary facies shot. north to south zonal distribution in the central region. The content of calcium carbonate ranges from 2.8 to 10.5%, and its distributional trends to be more concentrated on the western muddy sediments near toward the China side rather than on the eastern sandy sediments. The accumulation rates obtained using Pb-210 geochronologies for the muddy sediments in the Central Yellow Sea showed ranges from 0.21 to 0.68 cm/yr or 0.176 to 0.714 g/$\textrm{cm}^2$. yr. The sedimentation rate from core CY96010 located in the eastern near side of Shandong Peninsula which is affected by the Huanghe River shows 0.68 cm/yr or 0.714 g/$\textrm{cm}^2$ . yr. The sediment cores CY96008 and CY96002 in the Central Yellow Sea, the estimated of sediment accumulation rates shows 0.21~0.23cm1yr or 0.176~0.220 9/$\textrm{cm}^2$.Vr respectively, which are much lower than above samples. These indicate that the muddy sediments in central area of the Yellow Sea may have received influence of the sediment discharge from the Huanghe River. The concentrations of Ca, Na, Sr, Ho, La, Tb, Ta and Ca/Ti ratio of the muddy sediments in the Central Yellow Sea are higher than those of the Changjiang sediments and lower than those of the Huanghe sediments. However, these element values showed similar concentration patterns than those of the Huanghe sediment. The element contents such as Fe, Ti, Nl, Co, Cr, Cu, Pb, Sc, Ce, Nd, Sm, Eu, Cd and Dy in the study area are higher than those of the Huanghe sediments and lower than the Changjiang River sediments, but these values showed close to resemblance content trends those of the Changjiang sediment. The concentration of Mn, K and Sr in sediments of the study area are similar to those of the Keum River and eastern Yellow Sea sediment. They are rich in Zn, Rb, Cd, U, Cs and Li than those of the other comparison legions. Therefore, the terrigenous materials sources of the muddy sediment in the Central Yellow Sea comes mainly from Huanghe River in the past and present, and also have party derived from the Changjiang and Keum River, while the biological deposit in this area are carried by the Yellow Sea Warm Current.

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Three-Dimensional High-Frequency Electromagnetic Modeling Using Vector Finite Elements (벡터 유한 요소를 이용한 고주파 3차원 전자탐사 모델링)

  • Son Jeong-Sul;Song Yoonho;Chung Seung-Hwan;Suh Jung Hee
    • Geophysics and Geophysical Exploration
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    • v.5 no.4
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    • pp.280-290
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    • 2002
  • Three-dimensional (3-D) electromagnetic (EM) modeling algorithm has been developed using finite element method (FEM) to acquire more efficient interpretation techniques of EM data. When FEM based on nodal elements is applied to EM problem, spurious solutions, so called 'vector parasite', are occurred due to the discontinuity of normal electric fields and may lead the completely erroneous results. Among the methods curing the spurious problem, this study adopts vector element of which basis function has the amplitude and direction. To reduce computational cost and required core memory, complex bi-conjugate gradient (CBCG) method is applied to solving complex symmetric matrix of FEM and point Jacobi method is used to accelerate convergence rate. To verify the developed 3-D EM modeling algorithm, its electric and magnetic field for a layered-earth model are compared with those of layered-earth solution. As we expected, the vector based FEM developed in this study does not cause ny vector parasite problem, while conventional nodal based FEM causes lots of errors due to the discontinuity of field variables. For testing the applicability to high frequencies 100 MHz is used as an operating frequency for the layer structure. Modeled fields calculated from developed code are also well matched with the layered-earth ones for a model with dielectric anomaly as well as conductive anomaly. In a vertical electric dipole source case, however, the discontinuity of field variables causes the conventional nodal based FEM to include a lot of errors due to the vector parasite. Even for the case, the vector based FEM gave almost the same results as the layered-earth solution. The magnetic fields induced by a dielectric anomaly at high frequencies show unique behaviors different from those by a conductive anomaly. Since our 3-D EM modeling code can reflect the effect from a dielectric anomaly as well as a conductive anomaly, it may be a groundwork not only to apply high frequency EM method to the field survey but also to analyze the fold data obtained by high frequency EM method.

Occurrence and Chemical Composition of Chlorite and White Mica from Drilling Core (No. 04-1) at Gubong Au-Ag Deposit Area, Republic of Korea (구봉 금-은 광상일대 시추코아(04-1)에서 산출되는 녹니석과 백색운모의 산상 및 화학조성)

  • Bong Chul Yoo
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.4
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    • pp.273-288
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    • 2023
  • The Gubong Au-Ag deposit, which has been one of the largest deposits (Unsan, Daeyudong, Kwangyang) in Korea, consists of eight lens-shaped quartz veins (a mix of orogenic-type and intrusion-related types) that filled fractures along fault zones within Precambrian metasedimentary rock. Korea Mining Promotion Corporation found a quartz vein (referred to as the No. 6 vein with a grade of 27.9 g/t Au and a width of 0.9 m) at a depth of -728 ML by drilling (No. 90-12) conducted in 1989. Korea Mining Promotion Corporation conducted drilling (No. 04-1) in 2004 to investigate the redevelopment's possibility of the No. 6 vein. The author studied the occurrence and chemical composition of chlorite and white mica using wallrock, wallrock alteration and quartz vein samples collected from the No. 04-1 drilling core in 2004. The alteration of studied samples occurs chloritization, sericitization, silicification and pyritization. Chlorite and white mica from mineralized zone at a depth of -275 ML occur with quartz, K-feldspar, calcite, rutile and pyrite in wallrock alteration zone and quartz vein. Chlorite and white mica from ore vein (No. 6 vein) at a depth of -779 ML occur with quartz, calcite, apatite, zircon, rutile, ilmenite, pyrrhotite and pyrite in wallrock alteration zone and quartz vein. Chlorite from a depth of -779 ML has a higher content of Al and Mg elements and a lower content of Si and Fe elements than chlorite from a depth of -275 ML. Also, Chlorites from a depth of -275 ML and -779 ML have higher content of Si element than theoretical chlorite. Compositional variation in chlorite from a depth of -275 ML was mainly caused by phengitic or Tschermark substitution [Al3+,VI + Al3+,IV <-> (Fe2+ or Mg2+)VI + (Si4+)IV], but compositional variation from a depth of -779 ML was mainly caused by octahedral Fe2+ <-> Mg2+ (Mn2+) substitution. The interlayer cation site occupancy (K+Na+Ca+Ba+Sr = 0.76~0.82 apfu, 0.72~0.91 apfu) of white mica from a depth of -275 ML and -779 ML have lower contents than theoretical dioctahedral micas, but octahedral site occupancy (Fe+Mg+Mn+Ti+Cr+V+Ni = 2.09~2.13 apfu, 2.06~2.14 apfu) have higher contents than theoretical dioctahedral micas. Compositional variation in white mica from a depth of -275 ML was caused by phengitic or Tschermark substitution [(Al3+)VI + (Al3+)IV <-> (Fe2+ or Mg2+)VI + (Si4+)IV], illitic substitution and direct (Fe3+)VI <-> (Al3+)VI substitution. But, compositional variation in white mica from a depth of -779 ML was caused by phengitic or Tschermark substitution [(Al3+)VI + (Al3+)IV <-> (Fe2+ or Mg2+)VI + (Si4+)IV] and direct (Fe3+)VI <-> (Al3+)VI substitution.

A Study about Development of Environment Printing Technology and $CO_2$ (환경 인쇄 기술의 발전과 인쇄물의 $CO_2$ 발생량에 관한 연구)

  • Lee, Mun-Hag
    • Journal of the Korean Graphic Arts Communication Society
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    • v.30 no.3
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    • pp.89-114
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    • 2012
  • For as to world, the concern about the environment problem is enhanced than any other time in the past because of being 21 century. And the environment problem is highlighted as the world-wide issue. The time of the environment problem intimidates the alive of the mankind and presence of an earth over the time. It becomes the essentiality not being selection in the personal living or the economical viewpoint now to prepare for the climatic modification. As to the company management, the green growth period which it excludes the environment management considering an environment, cannot carry on the company the continued management comes. That is, in the change center of the management paradigm, there is the environment management. Nearly, the greenhouse gas which the publication industry is the environmental toxic material like all industries is generated. The greenhouse gas is ejected in the process of running the manufacturing process and print shop of the various kinds material used as the raw material of the book. Particularly, the tree felling for getting the material of the paper is known to reach the direct influence on the global warming. This study does according to an object it considers and organizes the environment parameter based on this kind of fact as to the publication industry. And it is determined as the reference which is used as the basic materials preparing the case that carbon exhaust right transaction(CAP and TRADE) drawing are enforced in all industries and is sustainable the management of the publication industry and reduces the environmental risk among the company many risk management elements and plans and enforces the publication related policy that there is a value. In the printing publication industry, this study tried to inquire into elements discharging the environmental pollutant or the greenhouse gas. Additionally, in the printed publication production process, it tried to inquire into the effort for an environment-friendly and necessity at the printing paper and the printers ink, regarded as the element discharging the greenhouse gas all kinds of the printing materials, operation of the print shop and all kinds of the machines and recycle process, and etc. These considerations make these industrial field employees aware of the significance about a conservation and environmental protection. They try to give a help in the subsequent study producing quantitatively each environmental parameter emission of green house gas. This makes the calculation of the relative $CO_2$ output reproached ultimately possible. Meanwhile, in a sense, many research protects and improving an environment in connection with the contents of research at the printing publication industrial field is in progress. There will be the voluntary human face that it has to protect an environment but this can not do by the outside factor according to all kinds of environment related law and regulation. Anyway, because of acting on company management as the factor of oppression, the increase of this environment-related correspondence cost could know that the research that the environment loading relates with a procurement and development, environment management system introduction, quality control standard, including, normalizing including a material, and etc. through the part of the effort to reduce the cost low was actively in progress. As to the green growth era, as follows, this paper prescribed the subject and alternative of the print publication industry. It is surrounded by the firstly new digital environment and the generation of the subject. And secondly the printing industry is caused by the point of time when the green growth leaves by the topic which is largest in the global industry and it increases. The printing publication industry has to prepare the bridgehead for the environment-friendly green growth as the alternative for this resolution with first. The support blown in each industry becomes the obligation not being selection. Prestek in which the print publishing was exposed to spend many energies and which is known as the practice of the sustainable print publishing insisted that it mentioned importance of the green printing through the white pages in 2008 and a company had to be the green growth comprised through the environment-friendly activity. The core management for the sustainable printing publication industry presented from Presstack white pages is compacted to 4 words that it is a remove, reduce, recover, and recycle. Second, positively the digital printing(POD) system should be utilized. In the worldwide print out market, the digital printing area stops at the level of 10% or so but the change over and growth of the market of an analog-to-digital will increase rapidly in the future. As to the CEO Jeff Hayes of the Infoland, the offset print referred to that it of the traditional method got old and infirm with the minor phase of the new printing application like the customer to be wanted publication and the print of the digital method led the market. In conclusion, print publishers have to grasp well the market flow in the situation where a digitalization cannot be generalized and a support cannot avoid. And it keeps pace with the flow of the digital age and the recognition about the effort for the development and environment problem have to be raised. Particularly, the active green strategy is employed for the active green strategy.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

Development of Needs Extraction Algorithm Fitting for Individuals in Care Management for the Elderly in Home (재가노인 사례관리의 욕구사정 정확도 향상을 위한 욕구추출 알고리즘 개발 - 데이터 마이닝 분석기법을 활용하여 -)

  • Kim, Young-Sook;Jung, Kook-In;Park, So-Rah
    • Korean Journal of Social Welfare
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    • v.60 no.1
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    • pp.187-209
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    • 2008
  • The authors developed 28 needs assessment tools for integrated assessment centered on needs, which is the core element in care management for the elderly in home. Also, the authors collected the assessment data of 676 elderly persons in home from 120 centers under the Korea Association of Senior Welfare Centers by using the needs assessment tools, and finally developed needs extraction algorithm through decision tree analysis in data mining to identify their actual needs and provide social welfare service suitable for such needs. The needs extraction algorithm for 28 needs of the elderly in home are summarized in

    . The Need No. 8 "Having need of help in going out" of the decision-making model, for example, was divided into 80.3% of asking for help and 11.4% not asking for help with Appeal No. 23 as a major variable. The need increased by 87.9% when the elderly appealed for help to go out and they had a caregiver but decreased by 47.4% when they had no caregiver. When the elderly asked for help in going out, they had a caregiver, and they needed complete help in cleaning, their need of help in going out was shown as 94.2%. However, seen from their answer that they needed complete help in bathing of ADL even if they did not ask for help in going out, it was found that the need of help in going out sharply increased from 11.4% to 80.0%. On the other hand, when they needed partial help or self-supported in bathing, the potential for them to be classified as asking for help in going out was shown to be low as 7.7%. In the said decision-making model, the number of cases for parent node and child node was designated as 50 and 25, respectively, with level 5 of the maximum tree depth as stopping rule. By this, it was shown that their decision-making was found to be effective as 182.13% for the need "Having need of help in going out". The algorithm presented in this study can be useful as systematic and scientific fundamental data in assessment of needs of the elderly in home.

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  • A Study on the Application and Development of Contents through Digitalizing Korean Patterns (한국문양의 디지털컨텐츠 개발과 활용에 관한 연구)

    • 박현택
      • Archives of design research
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      • v.16 no.3
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      • pp.201-210
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      • 2003
    • The world is preparing another unseen war, that is, the cultural war of digital economy which will dominate the new millenium. As the “contents”, which are composed of various ingredients of media, gain vitality, the developed nations are in preparation of the war with the “cultural industry” weapons. The digital economic experts say that the left out nations will become economic colony in the new millenium age. The most important characteristics of cultural industry is the unity of creativity and culture which is all the more improved on the basis of the culture created upon knowledge. This leads to competition between nations or regions, and to survive one has to develop the industrial structure through cognition of its own cultural value. Furthermore, it is not a short-term development and investment of cultural products but a study on the method to graft the cultural value to the industry itself. The multi-media period does not accept an independent medium, and the contents products are becoming the leading industry since il is proved that they last semi-permanently in the digital world. The victory lies in the quality and quantity of the contents as the high ability and variety of the technology of media advance in accordance to the market principles. Since the culture, science and economy are becoming one complex structure, all nations of the world are trying the evolve a unique design of their on culture on the basis of the global universality. In consequence, we should excavate a uniqueness from our cultural heritage and develop into a korean design which will be recognized in the world market. The value of our cultural property should not only be used as academic and research purposes but should be re-evaluated with modem view, recognized as the core element that decides the quality of life and developed into exclusive designs. The korean designs represent the mould concept of our people which evolves from the mould or shape alphabet of Korea To meet the requirements of the changing world and in preparation of the cultural competitive age, it is never too early to make a data on the korean designs through their analysis and evaluation.

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    Metamorphic Evolution of Metabasites and Country Gneiss in Baekdong Area and Its Tectonic Implication (백동지역의 변성염기성암과 주변 편마암의 변성진화과정과 그 지구조적 의미)

    • 오창환;최선규;송석환
      • The Journal of the Petrological Society of Korea
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      • v.11 no.3_4
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      • pp.103-120
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      • 2002
    • In the Baekdong-Hongseong area, the southwestern part of the Gyeonggi Massif in Korea, ultramafic rocks occur as lenses within Precambrian granitic gneiss. At Baekdong area, ultramafic lens contains metabasite boudin which had undergone at least three stages of metamorphisms. The mineral assemblage on the first stage, Garnet+Sodic Augite+Hornblende+Plagioclase+Titanite, is recognized from the inclusions in garnet. The second stage is represented by the assemblage in matrix, Garnet+ Augite+Hornblende+Plagioclase, while the third stage is identified by the Hornblende+Plagjoclase $\pm$ Garnet assemblage in the symplectite formed around garnet. The P-T conditions of the first and the third stages are $690-780^{\circ}C$, 11.8-15.9 kb and $490-610^{\circ}C$, 4.0-6.3 kb, respectively. These data indicate that metabasite in Baekdong area had experienced a retrouade P-T path from the eclogite(EG) - high-pressure granulite (HG)-amphibolite (AM) transitional facies to the AM through HG-AM transitional facies. The core and rim of garnet in country granitic gneiss give $605-815^{\circ}C$, 10.7-16.0 kb and $575-680^{\circ}C$, 5.4-7.0 kb, respectively, indicating that the retrograde P-T path of granitic gneiss is similar to that of metabasite. Trace element data reveals that the tectonic setting of metabasite is island uc. The general geology, the metamorphic evolution, the mineral chemistry and the tectonic setting of Baekdong area indicate that the Baekdong-Hongseong area in Korea is a possible extension of the Sulu collision Belt in China. On the other hand, the Sm-Nd whole rock-garnet isochron ages of metabasites are 268.7-297.9 Ma which are older than the ages of UHP metamorphism (208-245 Ma) in the Dabie-Sulu Collision Belt. The older metamorphic ages suggest that collision between Sino-Korea and Yangtz plates may have occurred earlier in Korean Peninsula than China.


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