• The Journal of Engineering Geology
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• v.27 no.4
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• pp.417-427
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• 2017

This study aims to present cases of rock slope failures caused by geological structures. Status of slope failures, results of cause analysis and stabilizing methods are introduced, focusing primarily on rock slope failures caused by specific geologic structures, such as intersection of faults infilled with clay, foliation and fault shear zone by dike intrusion and deep-seated clayey layer along lithologic boundary. Detailed geological survey, geophysical exploration and boring survey were conducted for cause analysis. Stabilizing method to prevent further slope failures and to ensure long-term stability of slopes were established, considering characteristics of geological structures, types of failure and geological conditions.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.3
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• pp.60-75
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• 2004

The purpose of this research is to evaluate five types of eco-village planning in order to introduce a landscape unit concept and theory in Korea. Although they had different backgrounds and motives of eco-villages planning, their common goal is to always maintain ecological planning and design in their villages. As concrete methods of ecological planning, we suggest three fundamental planning theories. 1. The boundary of a plan unit should be a watershed. 2. The survey and analysis of village ecotopes should be done in that defined watershed. 3. These results should be applied in the site and lot planning of eco-villages. These 3 steps should be done in a process and relevantly. In the evaluation of the five eco-village planning types, we found three results. 1. On a viewpoint of watershed, most planners recognized a watershed in survey and planning stages unconsciously. But they did not mention watersheds concretely and did not use this concept in the planning stage. 2. They did not define the concept of ecotope, but most planners recognized land-uses and vegetations of villages and vicinities as ecotopes. Also these could be proper ecotopes, but they did not use these compartment of ecotopes in the planning of ecosystem structure in villages. In addition, they did not deeply survey and analyze the ecotopes of villages and its vicinity. 3. On the viewpoint of sites and lots planning, they did not relevantly use the characteristics of watersheds and ecotopes in sites and lots planning. Therefore, they failed to implement the indigenous lots and subdivisions plan. In the size of lots and sites, they did not seriously consider the carrying capacity of ecosystem. We hope that our suggestion about the establishment of eco-villages planning is a fundamental theoretical framework of ecological planning in future eco-village planning.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.145-151
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• 2003

The domestic and the industry wastes which mainly come out of human life activities have been usually processed mainly by the incineration method and/or the method of reclamation. The method of reclamation, specially open dumping, has caused significant environmental pollution problems on the local or regional soil and groundwater system by leachate. Therefore, to investigate the 3-D structure characteristics of environmental pollution area is one of the hot subjects. We applied dipole-dipole method of electrical resistivity survey to investigate 3-D environmental contamination characteristics of the Noeun landfill area. For electrical resistivity survey, the line for measurements was established parallel to the main boundary of the Noeun landfill, for effective investigation of the whole landfill area. The result shows that the uppermost layer of the Noeun landfill is believed to be stabilized completely, based on the result of electrical resistivity values. However, the lowest layer of the Noeun landfill was partially polluted by leachate. Therefore, the electrical resistivity survey method is believed to be the one of the most effective methods to investigate three-dimensional distribution of leachate occurred in the lower part of landfill area.

• Journal of Korean Society on Water Environment
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• v.33 no.6
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• pp.769-779
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• 2017

Nutrient (i.e., nitrogen and phosphorus) budgets are required under a 'Livestock Excreta Survey'. A nutrient budget is one of the agri-environmental indicators that calculates the difference between the inputs and outputs of the amount of nutrients within a certain boundary and for a certain time period (e.g., 1 year). In this study, a nutrients budget model was developed to effectively determine the surplus of nutrients within a region in Korea. The C# program language was used in order to facilitate the deployment of a graphical user interface (GUI) and to enhance compatibility. Also, the model was developed on Windows OS, which is the commonly used operating system in Korea. The model was based on the OECD/Eurostat nutrient budget method, and it was modified to consider manure composting procedures as well. There are key features of the nutrient budget model, including directly use of the original data sets from various input and output sources, and a collectively exchange of the address in different formats. The model can quickly show the results of various spatial and temporal resolutions with the same data, as well as perform a sensitivity analysis with coefficients and easily compareresults using tables and graphs. Further, it would be necessary to study the extension of the scope of utilization, such as the application of various nutrient budget methods. It would also be helpful to investigate both pre and postprocessing information such as linking input data through online systems.

• Geophysics and Geophysical Exploration
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• v.20 no.4
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• pp.226-231
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• 2017

Since microgravity survey aims to delineate subsurface density structures in small scale, it requires inversion method, which is able to resolve small scale structures. It can be achieved by adopting a stabilizing functional which separates density boundary distinctly, which is different concept from general inversion routines. We composed Matlab-based interactive two-dimensional microgravity data inversion package containing several kinds of inversion routines with different stabilizing functional, for handling various geologic conditions and survey purposes. Different kinds of inversion routines in the package were verified and examined with representative synthetic data sets generated by numerical modeling. In addition, we applied the developed package to a real microgravity survey data.

• Geophysics and Geophysical Exploration
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• v.10 no.4
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• pp.345-352
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• 2007

Two-dimensional (2D) MT surveys near the Century mine in Australia have been performed with very far remote reference in Esashi, Japan (RR_ESS) as well as Gregory Downs (RR_GREG), which are roughly 6,400 km and 80 km apart from the survey area, respectively. Good quality of MT data could be obtained by remote reference processing with RR_GREG, while the coherency of magnetic fields between field sites and RR_ESS was not sufficient to be used as remote data. Both 2D and 3D inversion of 2D profile data represented the general geological structure beneath the survey area. The main target of the survey, Termite Range Fault, appeared as a boundary between a conductive block to the north and a resistive block to the south in the reconstructed resistivity section, and is inclined slightly to the north-east direction.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.221-228
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• 2002

Thickness of concrete lining, voids at the back of lining or shotcrete are very important elements for inspecting the safety of tunnels. Therefore, the inspection of tunnel lining structure means to investigate the inner layer boundaries of the structure. For this purpose, seismic reflection survey is the most desirable method if it works in good conditions. However, the conventional seismic reflection method can not be properly used for investigating thin layers in the lining structure. In other words, to detect the inner boundaries, it is desirable for the wavelength of source to be less than the thickness of each layer and for the receiver to be capable of detecting high frequency(ultrasonic) signals. To this end, new appropriate source and receiver devices should be developed above all for the ultrasonic reflection survey. This paper deals primarily with the development of source and receiver devices which are essential parts of field measuring system. Interests are above all centered in both the radiation pattern, energy, frequency content of the source and the directional sensitivity of the receiver. With these newly devised ones, ultrasonic physical modeling has been performed on 3-D physical model composed of bakelite, water-proof and concrete, The measured seismograms showed a clear separation of wave arrivals reflected from each layer boundary. Furthermore, it is noteworthy that reflection events from the bottom of concrete below water-proof could be also observed. This result demonstrates the usefulness of the both devices that can be applied to benefit the ultrasonic reflection survey. Future research is being focus on dealing with at first an optimal configuration of source and receiver devices well coupled to tunnel wall, and further an efficient data control system of practical use.

• Journal of the Korean earth science society
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• v.24 no.4
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• pp.361-368
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• 2003

We have investigated the electric resistivity structure of the fault zone located in the Hongseong area where a big earthquake with M 5.0 occurred in 1978. Usually, Electric and Electromagnetic methods are broadly operated in the field of engineering works since these methods are effective to understand the distribution of geological weak zones - fault or fracture zones. We have conducted the dipole-dipole array resistivity method and MT(magnetotelluric) method and interpreted the resistivity distribution of the fault zone with the aid of various inversion methods. An MT survey was performed at 18 points along a 2.9 km survey line perpendicular to the fault line and a magnetic dipole source was used to enhance the S/N ratio in the high frequency. A Electric dipole-dipole array resistivity survey with the dipole length of 50 meters was carried out perpendicular to the fault. In view of two survey results, the fault marks the boundary between two opposite resistivity structures, especially the low resistivity zone is exhibited deeply through the prospective fault line. The result that the low resistivity zone is located at the center of the fault zone corresponds with the fact that the fault zone of the Hongseong area is active. We expect these results to provide basic information about the physical properties of fault zones in Korea.

• KIEAE Journal
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• v.7 no.2
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• pp.3-8
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• 2007

Recently, the structural system of public residential buildings has been changed from the reinforced concrete (RC) wall system to the (PC) wall and moment resisting systems. Thus, it is important to develop the suitable wall system in accordance with the trend of the modern structural system. This paper presents the basic study on the suitable boundary wall in high-rise buildings. The research also demonstrates the evaluation results on sound characteristics in the aspect of sound insulation. The evaluation of sound insulation capability for the commercialized wall structure was conducted based on literature survey while the measurement of sound insulation capability for the light-weght EPP concrete was performed in according to KS F2808 in laboratory. The main objective of this research is to propose the most suitable dry wall system as a sound insulation structure through the comparison and analysis of frequency characteristics and weight-acoustic attenuation.

• Journal of the Korean Institute of Landscape Architecture
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• v.19 no.2
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• pp.1-11
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• 1991

The style of "Lu$.$Chong" was analyzed to investigate the characteristics of korean traditional garden style or planning theories of garden. To carry out this study more effectively, a combinded approach was introduced. This approach consisted of two processes. One was the review of old literature and the other was field survey. About 65-80% of Lu$.$Chong were named after natural landscape elements or techniques of natural landscape treatment. The techniques was summarrized 'conversing-scape(聚景)', 'surround-scape', 'multiland-scape(多景)', 'far-off-scape(遠景)', and 'emptiness of Lu$.$ Chong or landscape'. The results were proved through the analysis of visual boundary, locational pattern and 'Palkyeong(eight-sceneries)'.