• Economic and Environmental Geology
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• v.20 no.2
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• pp.97-106
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• 1987

The geology of the Bupyeong mine area is consisted of Precambrian Gyeonggi gneiss complex and Mesozoic igneous rocks; i.e., pyroclastic rocks, intrusive breccia, granite and felsic porphyries which were formed during a Jurassic to early Cretaceous resurgent caldera evolution. Granites are not observed on the surface and in the underground of the mine. Bupyeong silver deposits occur as stockworks of base metal sulfides- minor silver minerals-quartz - carbonate veinlets, hosted by pyroclastic rocks and intrusive breccia at the southwestern margin of the caldera. Silver occurs mainly as native silver, and other silver minerals, minor in quantity, are argentite, tetrahedrite-freibergite, pyrargyrite, polybasite, canfieldite and dyscrasite. The average grade of silver ore is about 180g/t Ag. Discrimination of silver ore from the country rocks depends largely on the chemical analyses of rock samples taken every two meters from tunnels, diamond-drilling cores and mining stopes, because silver minerals are hardly observed in the ore by crude eye, and silver orebodies do not properly coincide with the concentrated zone of base metal sulfides which were precipitated at the earlier stage than the stage of precipitation of native silver. General characteristics of the loci of the silver orebodies are as follows; (1) The host rocks of orebodies are pyroclastic rocks and intrusive breccia. (2) Many of the orebodies are distributed around Gyeonggi gneiss complex. Especially where the paleotopography of gneiss complex shows a gradual slope, the basal stratigraphic horizon of the pyroclastic rocks unconformably overlying the gneiss complex offered a favorable loci of high grade ore. (3) $N5^{\circ}W$ to $N15^{\circ}$ E-striking faults played an important role in the localization of the orebodies. (4) Conduits of intrusive breccia within the gneiss complex, through which the intrusive breccia intruded into the upper pyroclastic rocks, exist beneath most of the main orebodies. This suggests that the conduits of intrusive breccia served as channelways for the migration of ore fluids.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.47-53
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• 1999

This study was carried out to suggest the slope revegetation technology of biological engineering using the Ligustrum obtusifolium, which is one of the pioneer plant species. Ahead of the experimental construction, we evaluated the L. obtusifolium's value of biological engineering for the slope stabilization by testing the growth rate after the cuttings were buried for 8 weeks('98. 7. ~ '98. 9.). In this test, it was found that the L. obtusifolium, one of the species deep rooted with developed underground parts, is very effective for the slope stabilization and that the rooting powder(Hormex Powder) gave the better effects on root germination. In April of 1999, the experimental construction of biological engineering technology using recycled L. obtusifolium live cuttings(applied growth-stimulating compound) and green bags was conducted at sandy cut-slope in GLEN ROSS G.C.(Yongin). The slope was tolerant of soil erosion despite of heavy rainfall in the rainy season and many plant species invading for five months('99. 4. ~ '99. 9.). The vegetation research was performed through examining the frequency of each block using the transect method. 21 kinds of plant speices appeared in total area($25.5m^2$) and the dominant species are Digitaria sanguinalis, Setaria viridis, Cyperus amuricus, Persicaria blumei, Artemisia princeps var. orientalis. With regard to life forms, therophytes were shown with a dominant distribution of 66.7% of total species and neophytes relatively with a low distribution of 19.0%. Furthermore, it can be estimated that there is no ecological stabilization of this slope with the result of the ruderal species' occupation of 71.4%. It is too early to argue about ecological mechanical advantages and disadvantages of this technology, but, from the result of this study, it is expected that the slope revegetation technology of biological engineering using L. obtusifolium can be effectively applied to sandy slope(not rock or weathered rock slope) and that the early rapid stabilization and favorable succession could be done with the improvement of soil condition.

• Journal of the Korean Geophysical Society
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• v.8 no.2
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• pp.89-92
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• 2005

For the understanding the locus of the Quinling-Dabie-Sulu continental collision’s boundary and the underground structure of the sedimentray basin in the Yellow Sea, three dimensional density modelling is carrid out by using gravity dataset (Free Air Anomaly), which is measured by Tamhae 2, GIGAM in a period 2000-2002. The measured gravity anomaly in the investigations area is mainly responsed by depth distribution of the sedimentary basin. After comparing the sea-measured gravity data to CHAMP-GRACE satellite gravity data, I suggested that the high density model bodies extend mainly from the southern part of China to the middle-western part of the Korean Peninsula, which might be emplaced along the continental collision’s boundary. The total volume of very low density bodies modified by modelling might be about 20 000 km3.

• Journal of Korea Water Resources Association
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• v.53 no.spc1
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• pp.743-753
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• 2020

In this study, research trends in the water resources in Korea were analyzed to present regional customization and optimal operation management of groundwater resources. Detailed classification fields were determined in the water and groundwater resources. Through the analysis of examples and trends of research related to water resources and underground water resources, three improvements were presented: securing sites for long-term observable research area, evaluating water resources based on spatial units, and not reflecting the characteristics of watersheds in acts and ordinances. The research results of this study are expected to be the basis for policy judgment in determining the groundwater management policy after the group of groundwater management policy makers at the research site can identify the requirements.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.4
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• pp.116-121
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• 2012

The construction of underground structures such as box culverts for electric power transmission is increasing more and more, and the life extension of these structures is very important. Carbonation-induced corrosion in concrete may often occur in a high carbon dioxide environment. In this study, the risk of carbonation of two concrete box culverts in an urban area was evaluated by measuring the carbonation rate and concrete cover depth. Then, the carbonation-free service life at the depth of the steel was calculated, based on in situ information, by the Monte Carlo simulation. The service life of box culvert due to carbonation was estimated over 250 years via Monte Carlo simulation.

• Korean Journal of Construction Engineering and Management
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• v.18 no.1
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• pp.83-89
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• 2017

Temporary structures provide the accessible working area when building a permanent building structure in the construction operation. Executed in a natural environment, the temporary structure is prone to the external influence factors of underground water, soil conditions, etc. These factors should be carefully considered in designing the temporary structure. The objective of this study is to apply the external influence factors in designing a more reliable earth retaining wall. The research methodology is based on the Taguchi method that has been studied to improve product quality in the industry. An orthogonal array was developed to analyze the interaction between the external influence factors and the internal influence factors. A sample case study demonstrated that the Taguchi method can be used in planning a more reliable temporary structure for earth retaining walls.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.1
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• pp.1-22
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• 2011

The challenge shop is a means of countermeasure for empty store at downtown in Japan and takes effect all part of the city from 2000. Local self-government, chamber of commerce and industry or other organizations introduce the challenge shop with the object of a nurture talent. Raises the talented man can be the commencement of an enterprise to empty store from the area. It will reduce the empty store. But it is hard to accomplish purpose of business only by the founder of recruitment in manage challenge shop. Even though the challenge shop is not making more active only one time that is contributing to business district. This study focuses on the key success factor based on the way of managing challenge shops in Japan and draws the conclusion from the domestic challenge shop of Anyang Central market and Daejeon underground Central market that one market-on-one university exclusive charge system produces founders of new business.

• Computational Structural Engineering
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• v.7 no.4
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• pp.57-67
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• 1994

It is usual that underground structures are constructed within a multi-layered medium. In this paper, an efficient numerical modelling of multi-layered structural systems is studied using coupled analysis of finite elements and boundary elements. The finite elements are applied to the area in which the material nonlinearity dominates, and the boundary elements are applied to the far field where the nonlinearity is relatively weak. In the boundary element modelling of the multi-layered medium, fundamental solutions are not readily available. Thus, methods which can utilize existing Kelvin solutions are sought for the interior multi-layered domain problem. The interior domain problem which has piecewise homogeneous layers is analyzed using boundary elements with Kelvin solution, by discretizing each homogeneous subdomain and enforcing compatibility and equilibrium conditions between interfaces. Developed methodology is verified by comparing its results with those from the finite element analysis and it is concluded that coupled analysis using boundary elements and finite elements can be reasonable and efficient.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.32-35
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• 2008

If human beings could make friends with nature, it would be a truly wellbeing. This project has selected the design concept under the supposition that human beings and the nature become friends. This residential house, which is consisted of one ground floor and two underground floors, is confronting the mountains that surround the residential complex. Residents can enjoy viewing the mountains from the living room. The garden is created by using this given environment in maximum. The walls are made up with rocks, and a small pond is formed with water from the mountain, presenting another attractive sight. Through the connection rather than the break between mountain and garden, living room and garden, and again garden and mountain, the dialogue with nature was attempted. The water of the pond in the garden flows down along the walls and creates another water space at the gate area of the house. Passing through the entrance, there are a living room, a kitchen, a bedroom for spouses, a common bathroom, and a library on the ground floor. On the second floor, there are two rooms, a bathroom, and a mini living room. The platform of living room on the 1st floor is lowered to produce the comfortable living room with the hearth. From the view of living room, the garden with full feeling of nature can give a good emotional rest for modem people who want the mental relaxation. The marble stones are used as its material to present rich texture and sophisticated image presentation. The hearth in the living room is harmonized with high-tech electronic home appliances and surrounding accessories. On the kitchen, the high-glossy materials are used to express the external appearance neatly and the depository function is more improved for housewives.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2738-2744
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• 2014

For balanced development of the Sejong City, early settlement in transport infrastructure should precede the most. Of various means of transport, this study focus on BRT(Bus Rapid Transit) and the railway. Than the subway construction costs only a tenth. Equipped with a system of underground transport capacity to significantly increase the new concept of public transport in the BRT, utilizing the existing line railway to be constructed broad Chungcheong. The extension revolves 1 line of Daejeon subway to Jeongbuse kind government complex and the communication facilities is cooked for the rapid increase in the transportation demand according to the before central administration organization and Sejong city inflow of population.