• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 1999.12a
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• pp.47-51
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• 1999

Geo-features play a key role in object-oriented or feature-based geo-processing system. So the strategy for how-to-model and how-to-manage the geo-features builds the main architecture of the entire system and also supports the efficiency and functionality of the system. Unlike the conventional 2D geo-processing system, geo-features in 3D GIS have lots to be considered to model regarding the efficient manipulation and analysis and visualization. When the system is running on the Web, it should also be considered that how to leverage the level of detail and the level of automation of modeling in addition to the support for client side data interoperability. We built a set of 3D geo-features, and each geo-feature contains a set of aspatial data and 3D geo-primitives. The 3D geo-primitives contain the fundamental modeling data such as the height of building and the burial depth of gas pipeline. We separated the additional modeling data on the geometry and appearance of the model from the fundamental modeling data to make the table in database more concise and to allow the users more freedom to represent the geo-object. To get the users to build and exchange their own data, we devised a fie format called VGFF 2.0 which stands for Virtual GIS File Format. It is to describe the three dimensional geo-information in XML(extensible Markup Language). The DTD(Document Type Definition) of VGFF 2.0 is parsed using the DOM(Document Object Model). We also developed the authoring tools for users can make their own 3D geo-features and model and save the data to VGFF 2.0 format. We are now expecting the VGFF 2.0 evolve to the 3D version of SVG(Scalable Vector Graphics) especially for 3D GIS on the Web.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.173-182
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• 2001

The physical properties and biodegradability of cellulose fabrics, such as cotton and rayon, are expected to vary with textile care. In this study cotton and rayon fabrics were washed repeatedly with detergents, bleaches, or softeners. The changes of physical properties were investigated by measuring retention of breaking strength, shrinkage, handle, and the fiber surface was observed by SEM. The biodegradability of fabrics was also estimated by soil burial test. The results were as follows. Cotton fabrics laundered repeatedly by detergents and bleaches lost virtually no strength. The breaking strength of the rayon fabrics decreased by about 17%∼25% after repeated launderings. Shrinkage in weft direction was much larger than that in warp direction. Bending rigidities of both fabrics decreased remarkably within 10 wash cycles. Shear rigidity in cotton fabrics increased continuously with repeated washing cycles, however, that in rayon fabrics did not show any change as washing went on. Friction coefficient increased in both fabrics after 10 wash cycles, and this is thought to be attributed to the wrinkle, interlocking of hairs, surface damage resulted from repeated washings. In cotton fabrics made of staple yarns, short hairs on the yarn surface entangled together with repeated launderings. This resulted in the continuous increase in % shrinkage, shear rigidity, friction coefficient. Rayon fabrics made of filament yarns, however, did not show this phenomenon. Softener treated fabrics showed the lowest values in bending rigidity, shear rigidity and friction coefficient because the cationic surfactants adsorbed on the fiber surface behaved like lubricants. The biodegradability of fabrics was noticeably affected by the composition of washing solutions. The fabrics washed with detergents and bleaches were decomposed faster than those washed with the others were and the cotton fabrics washed with detergents and softeners hardly degraded. The fabrics soiled with milk were decomposed almost completely and those soiled with Palmitic acid did not degrade greatly.

• 한국해양학회지
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• v.30 no.3
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• pp.216-226
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• 1995

Stable isotopic and elemental compositions were analyzed for well- preserved calcareous skeletons (gastropods, pectenids, brachiopods, a scaphopod, and other bivalves) of the Pleistocene Seoguipo Formation from Cheju Island, Korea. Mineralogically and texturally, aragonitic and calcitic fossils still retain their original mineralogy and microstructure. High $\delta$$\^$18/O and $\delta$$\^$13/C contents indicate that the shells have not been altered by the post-burial diagenesis. Also, this is supported by high Na and Sr contents as well as low Mn and Fe compositions of the shells. Oxygen isotopic compositions of the well preserved fossils show that the organisms had lived under the lower paleotemperature or within the isotopically enriched paleo-seawater during the deposition of the Seoguipo Formation. This result strongly implies that the Seoguipo Formation was deposited during a glacial period. The paleotemperature variation throughout the sequence during the deposition of the Sewguipo Formation was negligible.

• Journal of architectural history
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• v.21 no.1
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• pp.119-134
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• 2012

Balhae(698~926) was the ancient state which opened the Nambuk-guk period with the Unified Silla. But Balhae architecture began to included in the history of Korean architecture only about 15 years ago, such as the books written by Yun Jang-seop or Ju Nam-cheol. I discussed four issues related to Balhae architecture in this paper. First, I criticized the excavation report of 24 stones remains at Jiangdong in Duhua city, and I asserted the ondol site belonged to different period. Second, I also interpreted that the building found on the tombs no.13 and no.14, in the Longhai burial area in Helong city must be a wooden stupa. Third, Balhae played some important roles in the history of ondol. It developed Koguryeo ondol in terms of structure, gave an opportunity to the ruling class to adopt ondol for the first time, and passed the heating system down to the Jurchen, the ancestor of the modern Manchurian. Fourth, the Russian-Korean joint research team excavated seven building sites in Koksharovka 1 fortress from Russian territory these four years, and it is reasonable to assume the fortress was the center of Anbyeon-bu, one of 15 local government districts in Balhae. I guess this buildings were the royal shrine built by resisters after the fall of Balhae, and the vessel stands found there must be used for ancestral memorial ceremony inside them.

• Journal of Environmental Health Sciences
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• v.7 no.2
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• pp.73-87
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• 1981

Generation of Solid Wastes grew rapidly with the increase of living standard of the people in Korea recently and their composition was more complicate. The weight of Solid wastes generated in Seoul into year of 1979 was about 420 million tons which required 1.5 million $m^2$ of burial land and daily generation for person was 1.6kg. The Composition of more than 80% ash contents was suitable for sanitary landfill but recently ash was decreasing while paper, synthetic materials, glass etc, increasing and alternative method had to be found to dispose the wastes properly. Weight and Composition of Wastes by season and living standard were surveyed for one year from June 1980 to May 1981 in Seoul. Disposal mathods by waste composition was studied. Results were summarized as follows: 1) Each component stored separately at generation point was to be collected and to be reused or disposed by public organization or private company. Some incentives have to be arranged. 2) Wastes collected from household were transfeted to about 420 temporally storing places and transported to two dumping areas by about 700, 4-8 tons trucks which droped litters on the streets. Large dumping lots should constructed along the western coasts and the wastes would be transported through big container trucks or trains to the lots. 3) Ash contents decreased to 40-70% while garbage, synthetic materials, paper increased and they are two to three times in summer of those in winter. Ash in affluent residential areas is less than 50% of whole wastes while that in poor apartment and residential areas is 60-70%. 4) Large dumping places should be constructed along the western coasts which are not far from Seoul because no suitalbe lands are available, and proper leakage protection arrangements should be made.

• Journal of the Korean Institute of Gas
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• v.12 no.1
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• pp.7-12
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• 2008

In order to estimate the integrity and identify the dynamic characteristics of buried gas pipelines subjected to vehicle loads, FE analysis is performed based on the 'Highway and Local Road Design Criteria' and the 'KOGAS Guideline for Pipeline Management'. The FE model describes the current burial condition of Korea properly, and the DB-24 load model is adopted for this research. This study considers a varying velocity in the range of $40{\sim}160\;km/h$ and $P_i=8$ MPa(internal pressure) with depth cover, Z=1.5 m. Maximum stress occurs at v=80 km/h and decreases after v=80 km/h. The maximum induced stress by DB-24 loads is about 10 MPa. Under the design pressure, however, the analysis results show that API 5L Gr. X65 pipelines have sufficient integrity to withstand the vibration of vehicle loads.

• Journal of the Korean Institute of Gas
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• v.12 no.1
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• pp.13-18
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• 2008

Vibration velocity induced by earthquakes or external vibration sources is one of the integrity assessment indexes, and is also a representative value used to describe the amount of vibration because it is based on a proportional relationship with the damage scale. In this study, the vibration velocity criterion for structures is first examined. Then, based on the velocity criterion, an integrity assessment is performed. Burial condition is set up based on the "Highway and Local Road Design Criteria" with API 5L Gr. X65 pipeline(D=762 mm). The FE model considers DB-24 vehicle load as a time function with a varying velocity in the range of $20{\sim}160\;km/h$. Maximum vibration velocity occurs at v=80 km/h and decreases after v=80 km/h. The maximum vibration velocity of buried pipeline by DB-24 loads is about 0.034 cm/s. The velocity that occurs is in the range of allowable values for each vibration velocity criterion. The wave propagation velocity was identified based on attenuation law and the minimum value appears at vehicle velocity 80 km/h that has maximum vibration velocity.

• Geomechanics and Engineering
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• v.22 no.4
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• pp.291-303
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• 2020

The deformation of the rock surrounding a tunnel manifests due to the stress redistribution within the surrounding rock. By observing the deformation of the surrounding rock, we can not only determine the stability of the surrounding rock and supporting structure but also predict the future state of the surrounding rock. In this paper, we used grey system theory to analyse the factors that affect the deformation of the rock surrounding a tunnel. The results show that the 5 main influencing factors are longitudinal wave velocity, tunnel burial depth, groundwater development, surrounding rock support type and construction management level. Furthermore, we used seismic prospecting data, preliminary survey data and excavated section monitoring data to establish a neural network learning model to predict the total amount of deformation of the surrounding rock during tunnel collapse. Subsequently, the probability of a change in deformation in each predicted section was obtained by using a Bayesian method for detecting change points. Finally, through an analysis of the distribution of the change probability and a comparison with the actual situation, we deduced the survey mark at which collapse would most likely occur. Surface collapse suddenly occurred when the tunnel was excavated to this predicted distance. This work further proved that the Bayesian method can accurately detect change points for risk evaluation, enhancing the accuracy of tunnel collapse forecasting. This research provides a reference and a guide for future research on the probability analysis of tunnel collapse.

• Conservation Science in Museum
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• v.20
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• pp.1-12
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• 2018

In February 1986, a high-school student reported the discovery of fragments of gilt-bronze burial goods on a mountainside behind a village in Ipjeom-ri, Ungpo-myeon in Iksan. The National Research Institute of Cultural Heritage immediately undertook an excavation. Unfortunately, gilt-bronze relics including a band and vertical decorations for a crown, a hat, and shoes had already been collected from Ipjeom-ri Tomb 1 by the student who found them before they could be properly excavated. Also, the interior of the stone chamber of the tomb had been severely disturbed by the time of excavation, making it difficult to identify the precise original locations of the relics within the tomb and hindering the reassembly of the fragments of the gilt-bronze crown. After conservation treatment, the gilt-bronze hat, shoes, and other relics were restored to their original forms and researchers were able to identify incised designs of a three-legged bonghwang(鳳凰), fish scales, lotus flowers, and other motifs. This study presents the major features of the fragments of gilt-bronze relics from Ipjeom-ri Tomb 1 and the methods of their production in order to provide basic material for their restoration and allow the eventual restoration of the giltbronze crown to its original condition.

• Journal of the Mineralogical Society of Korea
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• v.22 no.2
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• pp.115-127
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• 2009

Mineral quantification was performed on sediments of the Ulleung basin by X-ray powder diffraction and the computer software based on Rietveld quantification method. The sediments are dominated by amorphous opal-A with quartz, feldspars, micas, clays, calcite, and pyrite. The opal-A shows iterative variation in abundance with increasing burial depth. In addition, the relative abundance of opal-A is coincident with abundance of organic carbon contents, indicating that the Ulleung sediment consists mostly of amorphous silica derived from organism in the pelagic environment. Upward increase in the abundance of opal-A is markedly shown in the cores located in the slope region. On the other hand, there is a distinct tendency that the abundance of calcite is inversely proportional to that of opal-A. This indicates that the abundance of opal-A increases during the rise of sea level. Also, the fall of sea level lowers the abundance of opal-A.