• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.59-67
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• 2003

In this study, the change in hydraulic conductivity according to the changes in the contact area, aperture, confining pressure and temperature was observed to improve the reliability of the analysis of underground water flow. Also, the mechanical and thermal properties of domestic crystalline rocks in a great depth were obtained. It was found that the averaged intial aperture ranged from 544.33${\mu}{\textrm}{m}$ to 898.62${\mu}{\textrm}{m}$ and it followed a log-normal distribution. The hydraulic conductivity decreased with the increase of normal stress on the fracture surface and the hydraulic conductivity decreased as temperature increased. The change in hydraulic conductivity was strongly correlated with the change in contact area. It was verified by experiments that hydraulic conductivity was inversely proportional to the contact area. The measured mechanical and thermal properties were very close to the existing typical properties of domestic granites.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.247-247
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• 2017

Byobusan area of Aomori prefecture in Japan was a marshy sand dune and had developed for agricultural land use with a large-scale sprinkler system. Recently, it becomes an agricultural problem at this area that distinctive damage with browning maculation and fissures frequently occurs in Chinese yam tubers. Acetaldehyde is one of the factor candidates of underground part damage in plants. In this study, incidence rate of the tuber damage, and the morphological character and elemental composition of the damage parts in tubers were investigated with applications of excessive irrigation water or acetaldehyde water solution into the yam field. The incidence rate of the distinctive tuber damage increased as the input amount of irrigation water was increased. At the browning maculation parts of the tubers, many fissures and damages of cork layer were observed under scanning electron microscopy. In addition, the periderm of tubers was significantly thicker in damaged parts than in non-damaged parts. Funguses, bacterium and nematodes were not observed in the damaged part under scanning electron microscopy. The weight ratio of each constituent element in an analyzed area relative to the total weight of major essential elements was measured with energy dispersive X-ray spectrometry. The results showed that the weight ratios of boron, carbon, phosphorus, sulfur and calcium were higher in damaged parts than in non-damaged parts whereas the weight ratios of oxygen and chlorine were lower in damaged parts than in non-damaged parts. It was also shown by this spectrometry that iron, cadmium, lead and zinc were not directly involved in occurrence of the tuber damage. In this study, there was no remarkable difference of tuber appearance between non-acetaldehyde and acetaldehyde application treatments. From the above results, it is shown that the damage would be a physiological disorder induced by the input of a large quantity of water in the sandy field.

• Journal of the Korean Regional Science Association
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• v.14 no.1
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• pp.91-107
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• 1998

Waste disposal problem is one of the most important social welfare indicators in urban area, because the volume of waste generated from urban area is remarkable. So far most waste of Seoul has been disposed at landfills. However, this landifill disposal method is confronted with several difficulties in recent. As public concern on environmental problem increases and autonomy system is settled down, local community people of the landfills refuse to receive the waste produced other places any more. It brought reginal confliction problem between waste sending and receiving by refusing to accept waste from certain region. Furthermore, it is difficult to find another place to fill up the waste, while the existing landfiis is reached at the limit in the near future. In terms of environmental aspects landfill method is not the best way to dispose waste. It contaminates the soil and ground/underground water by leaking water containing many serious pollutants as well as offensive oder. In terms of equity, this waste disposal method is not fair. Environmental pollution causes damage to residence near to the landfills, while the waste produced other places. In order to satisfy the equity aspect, the waste generated a region should be disposed within the region. Incineration of Waste has been provided as the alternative. Government plans to construct waste incinerator in every anatomy, so the waste produced by local community is disposed within their local autonomous area. However, the location decision is not easy, since waste incinerator is one of the facilities to the community people. We can not apply the existing location models for this problem, because they show strong NIMBY phenomenon for the location. The location of waste incinerator should be determined very carefully with consideration of various location factors and criteria. This study proposes a methodology for determining the location of the waste incinerators by utilizing GIS, which is a power research tool for location decision where various geographical factors related. We drive the location factors which should be considered in the determination of waste incinerators. They involve environmental, socio-economic, and institutional factors. In first, we eliminate the area which is located within the environmental location criteria such as slope, fault line, distance to river, and then eliminate ares which is conflict with the social and institutional criteria.

• Economic and Environmental Geology
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• v.44 no.6
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• pp.525-532
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• 2011

In this study, the usefulness of underground dam as a means for the sustainable development of groundwater, and its performance in the management of groundwater resources were analyzed. The fully integrated SWAT-MODFLOW was applied to the Ssangcheon watershed in Korea to evaluate the effectiveness of groundwater dam construction. After construction, the groundwater level raised in the upstream area of groundwater dam while lowered in the downstream area. Also, it is shown that the exchange rate of river-aquifer interactions increased in the upper area of the dam. Since the storage capacity of the aquifer largely increased in the upper area of the dam, the exploitable groundwater could be greatly increased as much. This study demonstrated that a groundwater dam was a very useful measure to increase the available storativity of groundwater aquifers. It also represented that the combined analysis using SWAT-MODFLOW was helpful for the design and opeation of groundwater dam in the Ssangcheon watershed.

• The Journal of Engineering Geology
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• v.27 no.3
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• pp.217-231
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• 2017

The subsidence of ground in urban area can be caused by the occurrence of the cavity and the change in ground volumetric water content. The objective of this study is the detection of abnormal area of ground in urban area where the cavity or the change in ground volumetric water content is occurred by the ground penetrating radar signal. GPR survey is carried out on the test bed with a circular buried object. From the GPR survey, the signals filtered by the bandpass filtering are measured, and the methods consisting of gain function, time zero, background removal, deconvolution and display gain are applied to the filtered signals. As a result of application of the signal processing methods, the polarity of signal corresponds with the relation of electrical impedance of the cavity and the ground in test bed. In addition, the relative permittivity calculated by GPR signal is compared with that of predicted by volumetric water content of the test bed. The relative permittivities obtained from two different methods show similar values. Therefore, the abnormal area where the change in ground volumetric water content is occurred can be detected from the results of the GPR survey in case the depth of underground utilities is known. Signal processing methods and estimation of relative permittivity performed in this study may be effectively used to detect the abnormal area of ground in urban area.

• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.471-477
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• 2019

Rehmannia glutinosa is a perennial herb belonging to family Scrophulariaceae. This study was conducted to evaluate the appropriateness cultivation of R. glutinosa in Southern Gangwon Province. The seed rhizomes of R. glutinosa 'Jihwang 1' were planted in the early May and harvested in the early November. Agronomic characteristics and catalpol content was evaluated in comparison with Eumseong area. As a results, aerial parts of Pyeongchang area in leaf length and leaf width were better than other cultivation area but the leaf number per plant was statistically the same. And underground parts of Eumseong area in rhizome yield and number of rhizome were better than other cultivation area. Conversely, rhizome diameter of Pyeongchang and Jeongseon area were thicker than rhizome diameter of Eumseong area. The fresh rhizome yield of Eumseong, Jeongseon and Pyeongchang area were 1,848, 1,571, and 1485 kg/10a, respectively, higher than the domestic average production of 805 kg/10a. And, catalpol content of Pyeongchang, Jeongseon and Eumseong area were 1.93, 1.62 and 1.99%, respectively. Taken together, R. glutinosa cultivation in the region of southern Gangwon province is considered to be possible, but further evaluation of the economic aspect is needed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.4
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• pp.405-420
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• 2008

Resistivity survey is one of the widely used methods for the investigation of stability of the ground or bedrock around tunnel and is also used as an essential base data for stability and reduction of construction cost through first-hand approximation of rock quality at design step. Generally, the analysis of resistivity survey data is performed by single measurement. When distribution variation of groundwater around a tunnel over time is necessary for maintenance of a tunnel, resistivity monitoring is very useful survey method to grasp distribution variation of groundwater. So we performed the grid line resistivity survey to monitoring resistivity variation for six times. And we also tried to evaluate application possibility of the resistivity monitoring for construction safety through providing detailed information on fault zones.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.1
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• pp.41-56
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• 2017

Recently, the necessity of deep and double-deck tunnels has been grown day by day due to the increase of traffic volume at metropolitans and thus the study on the divergence of those tunnels becomes required. Therefore sensitivity analyses were conducted with FLAC 2D program by selecting ground condition, coefficient of lateral pressure, support pattern, and depth of rock cover as parameters. Ultimately, this study is to find the optimal shape and support method of a diverged section. As the results of this study, it turned out that the box type gave higher stability of the section than arch type unlike the general thought. It can be explained that the arch type has about 30% bigger excavation area than the box type. When the ground conditions are poor, steel pipe grouting reinforcement gives higher stability than rockbolt reinforcement, but its thickness and range do not give a great influence on the stability of the enlarged section.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.2
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• pp.101-106
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• 1993

This study is a efficient management techniques of road by facility database. The purpose of road ledger investigate the property of road facility, the present condition of the location, the quality of the material of the ground and underground facility. Also, this is used to make plan for construction, and investment program of the road. To build road database, photogrammetry, ground control surveying and aerial photogrammetry must be performed. After the research of the road facility, a underground facility map and the road drawings are to be made. In this study, model area is the KUMJUNG-KU in Pusan where an industrial road is located on. There are about 7,000 signal lampes and traffic safety boards. It is possible to manage scientifical and efficient road ledger though statistical handling using facility database. In this paper, authors found the database of road facility through basic circumstances in the use of SML of ARC/INFO.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.2
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• pp.165-176
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• 2005

A variety of research projects have been undertaken due to the recent catastrophic tunnel fires throughout the world, Among them, more emphasis was given to full scale and scale model fire experiments, and recently the area of fire resistance of tunnel structures attract more interests, On the contrary to the cases in most of the advanced countries where design standards as well as recommendations have already been announced, no local criteria for design can be found, This paper aims at deriving the fire characteristics appropriate for the assessment criteria of fire resistance of structures in local tunnels through studying the existing fire temperature curves including ISO 834 standard temperature curve, HC curve, RWS curve, ZTV curve and EBA curve.