• The Journal of Engineering Geology
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• v.30 no.1
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• pp.31-42
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• 2020

Electrical resistivity and downhole seismic surveys were conducted together with bore investigations and well-logging to examine subsurface structures in small-scale landslides at Sinjindo-ri, Geunheung-myeon, Taean-gun, Chungcheongnam-do, Republic of Korea in 2014. On the basis of the low N-values at depths of 5~7 m in borehole BH-2, downhole seismic and electrical dipole-dipole resistivity surveys were performed to delineate geological weak zones. The low-resistivity zones (<150 Ω·m) measure ~8 m in thickness and show a close depth correspondence to weathered soils consisting mainly of silty clays as identified from the bore investigations and well-logging data. Compared with weak zones in borehole BH-1, weak zones in BH-2 are characterized by lower densities (1.6~1.8 g/㎤) and resistivities (<150 Ω·m) and greater variation in Poisson's ratio. These observations can be explained by the presence of wet silty clays rich in weathered soil material that have resulted from heavy rainfall and rises in groundwater level. Downslope movements are probably caused by the sliding of wet clay that acts to reduce the strength of the weathered soil.

• The Journal of Engineering Geology
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• v.18 no.4
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• pp.359-369
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• 2008

For the design and effective management of underground storage caverns, preliminary investigation on the hydrogeologic parameters around caverns and analysis on the groundwater flow must be carried out. The data collection is very imporatnat task for the hydrogeologic design so various hydraulic tests have been performed. When analyzing the injection/fall off test data, existing graphical method to estimate the parameters in Theis' equation is widely used. However this method has some sources of error when estimating parameters by means of human faults. Therefore the method of estimating parameters by means of statistical methods such as regression type is evaluated as a useful tool. In this study, nonlinear regression analysis for the Theis' equation is suggested and applied to the estimation of parameters for the real field interference data around underground storage caverns. Damping parameter which reduce the iteration numbers and inhance the convergence is also introduced.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1139-1146
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• 2004

The purpose of this study was to investigate the possibility of Meles meles oil as an functional resource. To assess the effects of Meles meles oil in 25 non-insulin dependent diabetes mellitus (DM) persons, we examined changes of fat intake level, hematological and chemical variables, serum DM indices and lipid contents during the Meles meles oil supplementation. Polyunsaturated fatty acid and $\omega$3 fatty acid intake were significantly increased by Meles meles oil intakes. The levels of LDL-cholesterol and triglyceride were significantly decreased while HDL-cholesterol was significantly increased. Iron status improved during Meles meles oil intakes. These results show that modest dose of Meles meles oil supplementation can decrease serum triglyceride, cholesterol level without any changes in blood glucose level in NIDDM patients. These results indicated that Meles meles oil diet is effective therapeutic regimen for the control of metabolic derangements in diabetes mellitus. Also, these results imply that Meles meles oil can be used as possible food resources and functional food materials. However, large amounts of Meles meles oil should be used cautiously in NIDDM patients.

• Journal of the Korean earth science society
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• v.39 no.3
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• pp.291-302
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• 2018

The purpose of this study is to investigate pre-service middle school earth science teachers' perceptions about the learning of geological field trip. The study sample consists of 39 undergraduate students at the university located in a metropolitan city. Additionally, 4 pre-service earth science teachers are semi-structure interviewed. The instrument of the study includes a 5-category perception about the learning of geological field trip, which consists of needs, educational values, educational experience, teaching methods, and training for learning. The results are as follows. First, participants are important to the need and educational values of learning about the geological field trip regardless of gender and grade level. Second, all participants have experienced geological field trip in college. They have more opportunities to experiment for field trip as they advance to higher grade. There is significant difference between lower and higher graders in terms of the goal of learning about geological field trip. It needs a new lesson model to teach geology between men and women regarding teaching methods category. In order to practice geological field trip in school, participants perceive that they need the knowledge of geological context, experiment of field trips, and how to teach geological field trip to students. This study suggests that pre-service earth science teachers' perceptions include how to teach and learn geological field trip during their college year.

• The Journal of Engineering Geology
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• v.6 no.2
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• pp.95-102
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• 1996

A study on the attenuation of ground vibration was carried out on the soil layer using seismic exploration method. A 12-channel engineering seismograph was used to acquire real digital amplitude data in field work. Frequency analysis of seismic data shows maximum spectrum amplitude around 40Hz. Relative amplitude decreases exponentially as the distance increases and the attenuation factors are n = 0.25 and a = 0.13-0.20. Internal attenuation indexes(a) are 0.13 and 0.20 in the wet soil zone and the vegatated soil zone, respectively. It means that ground vibration attenuates faster in vegatated soil zone than in wet soil zone. Average internal attenuation coefficient(h) was determined to be 0.094 from seismic velocity and frequency analysis.

• The Journal of Engineering Geology
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• v.3 no.1
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• pp.51-61
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• 1993

Restricted maximum likelihood(RML) method was used to determine the parameters of generalized covariance, and universal krigig with RML was applied to estimate a groundwater level distribution of nonstationarv random function. Universal kriging with RML was compared to IRF-k with weighted least squares method for the comparison of their accuracies. Cross validation shows that two methods have nearly the same ability for the estimation of groundwater levels. Scattergram of estimates versus true values and contour maps of groundwater levels have nearly the same results. The reason why two methods produced the same results is thought to be the non-Gaussian distribution and the snaall number of sample data.

• Economic and Environmental Geology
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• v.28 no.5
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• pp.481-485
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• 1995

This paper presents a new approaching method to determine the velocity and geometry of shallow subsurface from seismic refraction events. After picking the first breaks from seismic refraction data, we assume that field refraction seismogram can be replaced by the unit delta function having time shift of first break. Time curves are generated by shooting ray tracing. The partial derivatives seismogram for a damped least squares method is computed analytically at each step of the forward ray tracing. The technique is successfully tested on synthetic and real data. It has the advantage of real full waveform inversion, which is robust at low frequency band even if the initial guess is far from the true model.

• Economic and Environmental Geology
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• v.36 no.2
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• pp.133-139
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• 2003

The purpose of this study is the analyses of the relationship between geology and terrain/satellite image in the southern part of the Bandung, Indonesia to provide basic information fur geological survey. For this, topography, geology and satellite image were constructed to spatial database. Digital elevation, slope, aspect, curvature, hill shade of topography were calculated from the topographic database and lithology was imported from the geologi-cal database. Lineament, lineament density, and NDVI were extracted the Landsat TM satellite image. The results showed the close relationship between geology and terrain and satellited image. Each sedimentary rocks seldom correspond with geology and analyses of topography but as a whole fur sedimentary rocks coincide with them. Tuff and volcanic breccia in the volcanic rocks correspond with the result of terrain analyses. Talus deposit is well matched with the analyses of topography/satellite image.

• Spatial Information Research
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• v.19 no.4
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• pp.81-89
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• 2011

This paper presents a multivariate kriging algorithm that integrates categorical data as secondary data for spatial interpolation of sparsely sampled ground survey data. Instead of using constant mean values in each attribute of categorical data, disaggregated local mean values at target grid points are first estimated by area-to-point kriging and then are used as local mean values in simple kriging with local means. This algorithm is illustrated through a case study of spatial interpolation of a geochemical copper element with geological map data. Cross validation results indicates that the presented algorithm leads to significant respective improvement of 15% and 25% in prediction capability, compared with univariate ordinary kriging and conventional simple kriging with constant mean values. It is expected that the multivariate kriging algorithm applied in this study would be effectively applied for spatial interpolation with categorical data.

• Proceedings of the KSEG Conference
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• 2002.04a
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• pp.235-248
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• 2002

Ground water development skill growth and life circumstances improvement increase ground water use. So managerial difficulties and various problems about ground water occur. Poor ground water management organization, lack of management person, thoughtless development add ground water pollution and lack of water volume. And local excessive developments or abandoned well occur. This paper presents ground water management system model making use of GIS and helps effective management by realizing necessary analysis functions in ground water management system and ground management methods. Local information of ground water recorded and development data, site examination data made D/B. And linearment analysis data making use of a satellite image data, hydraulic test data, the quality of water examination data, these local characteristic values made out thematic maps and making use of these data can form elementary data of ground water modeling It makes easy to understand environmental development conditions and pollution source conditions about new ground water development location, linearment growth, DRASTIC, the quality of water examination. Ground water management system making use of these functions can choose right location of ground water.