• The Journal of Engineering Geology
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• v.19 no.1
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• pp.71-79
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• 2009

Step-drawdown tests were conducted at four pumping Wells, two in porous media and two in fractured rocks, respectively. In general, P = 2.0 suggested by Jacob (1947) is applied to porous media and fractured rocks in terms of drawdowns of step-drawdown test. In an attempt to review problems of linear model (Jacob's graphic method) in interpreting the step-draw down test, the outcomes of well parameters (aquifer loss coefficient (B), well loss coefficient (C) and well loss exponent (P)) calculated from linear and nonlinear model (Labadie and Helweg's least-squares method) were compared and analyzed. The values of C and P calculated from linear and nonlinear models differed according to permeability of aquifer and the conditions of pumping well. The value C obtained from nonlinear models in porous media and fractured rocks is about $10^0{\sim}10^{-2}$ and $10^{-3}{\sim}10^{-6}$ times lower than in their linear models, respectively. The value P of porous media obtained from nonlinear model ranged from 2.123 to 2.775, while it ranged from 3.459 to 5.635 for fractured rocks. In case of nonlinear model, well loss highly depends on the value P. At this time, well efficiencies calculated from linear and nonlinear models were $1.56{\sim}14.89%$ for porous media and $8.73{\sim}24.71%$ for fractured rocks, showing a significant error according to chosen models. In nonlinear model, it was found that the regression analysis using the least squares method was very useful to interpret step-drawdown test in all aquifer.

• Economic and Environmental Geology
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• v.46 no.5
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• pp.375-390
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• 2013

The Kenticha rare-element (Ta-Li-Nb-Be) mineralized zone is located in ophiolitic fold and thrust complex of southern Ethiopia and was firstly discovered by joint exploration program of Ethiopia-Soviet in 1980s. It includes Dermidama, Kilkele, Shuni Hill, Kenticha, and Bupo pegmatites from south to north. The Kenticha pegmatite intruded parallel to NS-striking serpentinite and talc-chlorite schist, and is exposed approximately 2 km length and 400-700 m width. The Kenticha pegmatite is internally zoned and subdivided into lower quartz-muscovite-albite granite, intermediate muscovite-quartz-albite-microcline pegmatite, and upper spodumene-quartz-albite pegmatite, based on their mineral assemblage. The major, trace elements (e.g., Rb, Li, Nb, Ta, and Ga), and element ratios (e.g., K/Rb, Nb/Ta, Mg/Li, and Al/Ga) suggest that the fractionation and solidification of pegmatite have progressed from the lower towards upper pegmatite. In contrast, unlike general magmatic fractionation, Mg/Li ratios of the Kenticha pegmatite tend to be increased towards the upper pegmatite. It may result from post-magmatic hydrothermal alteration and/or interaction with upper ultramafic rock. Rare-element mineralization in Kenticha pegmatite concentrates on the upper pegmatite, which contains up to 3.0 wt % $Li_2O$, 3,780 ppm Rb, 111 ppm Cs, 1,320 ppm Ta, and 332 ppm Nb. Ore minerals in Kenticha pegmatite mostly include tantalite, spodumene, and lepidolite, and tantalite has an association with coarser quartz-spodumene and relatively fine sacchroidal albite. The tantalite is classified into Mn-tantalite as a function of $Mn^*[Mn/(Mn+Fe)]$ and $Ta^*[Ta/(Ta+Nb)]$ values. Its compositions ($Mn^*$, $Ta^*$, and Nb/Ta) between coarse and fine tantalites are different and the former is strongly enriched in Ta and depleted in Nb compared to latter one. In conclusion, rare-element mineralization in the Kenticha pegmatite may has occurred in the latest stage of magmatic fractionation.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.09a
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• pp.125-153
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• 2005

It has been widely known that the seismic piezo-cone penetration test (SCPTU) is one of the most useful techniques for investigating the geotechnical characteristics including dynamic soil properties. As the practical applications in Korea, SCPTU was carried out at two sites in Busan and four sites in Incheon, which are mainly composed of alluvial or marine soil deposits. From the SCPTU waveform data obtained from the testing sites, the first arrival times of shear waves were and the corresponding time differences with depth were determined using the cross-over method, and the shear wave velocity profiles (VS) were derived based on the refracted ray path method based on Snell's law and similar to the trend of cone tip resistance (qt) profiles. In Incheon area, the testing depths of SCPTU were deeper than those of conventional down-hole seismic tests. Moreover, for the application of the conventional CPTU to earthquake engineering practices, the correlations between VS and CPTU data were deduced based on the SCPTU results. For the empirical evaluation of VS for all soils together with clays and sands which are classified unambiguously in this study by the soil behavior type classification Index (IC), the authors suggested the VS-CPTU data correlations expressed as a function of four parameters, qt, fs, $\sigma$, v0 and Bq, determined by multiple statistical regression modeling. Despite the incompatible strain levels of the down-hole seismic test during SCPTU and the conventional CPTU, it is shown that the VS-CPTU data correlations for all soils clays and sands suggested in this study is applicable to the preliminary estimation of VS for the Korean deposits and is more reliable than the previous correlations proposed by other researchers.

• Korean Journal of Remote Sensing
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• v.30 no.4
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• pp.481-491
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• 2014

Blue-ice area is a glacial ice field in ice sheet, ice shelf and glaciers where snow ablation and sublimation is larger than snowfall. As the blue-ice area has large influences on the meteorite concentration mechanism and ice mass balance, it is required to quantify the concentration of blue-ice. We analyzed spectral reflectance characteristics of blue-ice, snow and cloud by using MODIS images obtained over blue-ice areas in McMurdo Dry Valleys, East Antarctica, from 2007 to 2012. We then developed Normalized Difference Blue-ice Index (NDBI) algorithm which quantifies the concentration of blue-ice. Snow and cloud have a high reflectance in visible and near-infrared (NIR) bands. Reflectance of blue-ice is high in blue band, while that lowers in the NIR band. NDBI is calculated by dividing the difference of reflectance in the blue and NIR bands by the sum of reflectances in the two bands so that NDBI = (Blue-NIR)/(Blue + NIR). NDBI calculated from the MODIS images showed that the blue-ice areas have values ranging from 0.2 to 0.5, depending on the exposure and concentration of blue-ice. It is obviously different from that of snow and cloud that has values less than 0.2 or rocks with negative values. The change of NDBI values in the blue-ice area has higher correlation with snow depth ($R^2=0.699$) than wind speed ($R^2=0.012$) or air temperature ($R^2=0.278$), all measured at a meteorological station installed in McMurdo Dry Valleys. As the snow depth increased, the NDBI value decreased, which suggests that snow depth can be estimated from NDBI values over blue-ice areas. The NDBI algorithm developed in this study will be useful for various polar research fields such as meteorite exploration, analysis of ice mass balance as well as the snow depth estimation.

• Korean Journal of Remote Sensing
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• v.34 no.3
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• pp.439-450
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• 2018

The lineament is a linear or curved terrain element to discriminate adjacent geological structures in each other. It has been widely used for analysis of geology, mineral exploration, natural disasters, and earthquake, etc. In the past, the lineament has been extracted using cartographic map or field survey. However, it is possible to extract more efficiently the lineament for a very wide area thanks to development of remote sensing technique. Remotely sensed observation by aircraft, satellite, or digital elevation model (DEM) has been used for visual recognition for manual lineament extraction. Automatic approaches using computer science have been proposed to extract lineament more objectively. In this study, we evaluate the characteristics of lineament which is automatically extracted with respect to difference of spatial resolution of DEM. We utilized two types of DEM: one is Shuttle Radar Topography Mission (SRTM) with spatial resolution of about 90 m (3 arc sec), and the other is the latest world DEM of TerraSAR-X add-on for Global DEM with 12 m spatial resolution. In addition, a global DEM was resampled to produce a DEM with a spatial resolution of 30 m (1 arc sec). The shaded relief map was constructed considering various sun elevation and solar azimuth angle. In order to extract lineament automatically, we used the LINE module in PCI Geomatica software. We found that predominant direction of the extracted lineament is about $N15-25^{\circ}E$ (NNE), regardless of spatial resolution of DEM. However, more fine and detailed lineament were extracted using higher spatial resolution of DEM. The result shows that the lineament density is proportional to the spatial resolution of DEM. Thus, the DEM with appropriate spatial resolution should be selected according to the purpose of the study.

• Journal of Science Education
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• v.38 no.3
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• pp.718-736
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• 2014

This study was intended to determine PCK of the middle school science teachers on Mendelian genetics and factors influenced to form their PCKs. Two science teachers with biology major with a teaching experience over 5 years were chosen as the subject. Data were collected by class observation, semi-structured interview, teacher questionnaire survey, Content Representation and Pedagogical and Professional-experience Repertoire. The collected data were analyzed based on Magnusson's PCK for science teaching consisting of five components: (a) the orientation toward teaching science, (b) the knowledge of science curriculum, (c) the knowledge of students' understanding, (d) the knowledge of assessment, and (e) the knowledge and belief in the instructional strategies to teach science. Teachers could have the orientation toward teaching science served as an assisting role to support students' abilities. Both subject teachers seemed to focus on giving lectures. Their efforts to improve students' exploration methods and abilities were not expressed enough in their real classes and they found that students struggled to understand Mendelian genetics. Therefore, they should have explained them in an easier way and worked harder to make their students understood accurately and applied basic and advanced concepts of Mendelian genetics. They found students' preconception and misconception regarding Mendelian genetics and wished to enhance their learning effects by various teaching strategies such as correcting misconception, adding the history of science and simply assessing students' affirmative domains. It was also found that factors influenced to form PCK regarding Mendelian genetics by both teachers were as follows: teacher's personality and endeavor, textbooks and guidance books, schools and their circumstances, teaching experience, experience as a learner, interaction with their colleagues, and university curriculum. Both teachers said that it was important for teachers to make every efforts to give better classes.

• Korean Security Journal
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• no.32
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• pp.7-32
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• 2012

This study aimed to evaluate the relative status using Analytic Hierarchy Process(AHP) on the spiritual factors of the security martial arts for the guards to perform the best security service. There were 540 participants who were students majored in security martial arts, workers for security and specialists of practical and theoretical security martial arts for this study. The exploratory and confirmatory factor analysis were carried out using the selecting data through literature reviews in the level of the factor-extraction about the spiritual characteristics. The specialists' survey was conducted on the relative status among factors using the spiritual concept structure based on the studied above. Selected data was calculated with SPSS 18.0 for windows, AMOS 5.0, and Expert Choice 2000 software. The conclusion can be made through those process above. First, 4 general factors and 20 detailed factors were found as the result of the factor exploration related to the spiritual characteristics of the security martial arts. The result which was verified on Construction validity of searched factors had stable figures on every standard. In other words, the participants for survey on this study "Spiritual characteristic concepts of the security martial arts" can be evaluated it is valid. The general factors of security martial arts' spirit were conceptualized with Psychological spirit, ethical spirit, martial art spirit, practical spirit through the naming process on the general factors of the security martial arts' spiritual characteristic concepts. The detailed factors of security martial arts' spirit were concentration, self-confidence, self-management, immersion, self-esteem in psychological spirit and sacrifice, justice, royalty, peace, sense of duty in ethical spirit and courtesy, toughness, defense, balance of mind and body, bravery in martial arts and responsibility, cooperation, modesty, determination, professionalism in practical spirit of security martial arts. That is, the conceptualization of security martial arts' spirit was verified that it had validity. Second, the hierarchical model of the security martial arts was composed with 4 superordinate concepts and 20 subordinate concepts. As the result of evaluating relative status based on Spiritual characteristics-hierarchy model, the impotance was proven in order of ethical spirit(.482), martial art spirit(.248), practical spirit(.188), psychological spirit(.083). Also the importance related to spiritual characteristics of security martial arts on subordinate concepts was proven in order of sacrifice(.252), courtesy(.110), sense of duty(.108), responsibility(. 073), royalty(.053), toughness(.052), justice(.049), defense(.038), professionalism(.038), determination(.035), cooperation(.029), self-confidence (.026), bravery(.025), self-esteem(.024), balance of mind and body(.023), peace(.019), concentration(.014), modesty(.013), self-management(.011), flow (.007). To sum up, the spiritual factor related to ethics such as sacrifice, justice, royalty, peace, sense of duty was the most important for the security martial arts.

• 한국지구물리탐사학회:학술대회논문집
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• 2000.09a
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• pp.54-69
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• 2000

There are groundwater trouble by high-salinity yield inducing sea-water intrusion in Cheju Island. It is used groundwater-GIS(Well-lnfo) in the maintenance and management of groundwater in Cheju Island to grasp groundwater trouble area and cause of high-salinity yield. For 16 wells certain to yield high-salinity, we logged specific electrical conductivity(EC) and tried to get hold of freshwater and saltwater relationship. As result of distribution of $Cl^-$ by depth, it is showed up groundwater trouble by high-salinity yield in the east coastal area and the partly north coastal area. The reason of high-salinity groundwater yield are low-groundwater level by the structure of geology and low-hydraulic gradient etc. There is necessity for management to development and use of groundwater in the high-salinity area, special management area.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.60-72
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• 2016

This study aims to suggest strategies of development and management for large parks by examining experimental cases of park governance models related to a shift away from public administration. The shifts towards governance as well as public-private partnership in city parks have involved the need for new public management. This study has analyzed two exemplary cases of Presidio Park and Sydney Harbour National Park in the aspects of planning process and management strategies, as the results derived the meaning and effect of park governance management and is also an essential prerequisite for the achievement of the model. There are six dimensions of research frames--namely policy, governance, partnership, finances and funds, design and maintenance-management, and evaluation-monitoring-taken as the basis for this study. Through the analysis, several key characteristics of these cases were elicited. First, the park planning process must be consistent in carrying a policy from planning to implementation, and furthermore, an independent operation body which can properly authorize an execution and uphold its responsibility from the public could serve in adaptable park services. Second, it has been suggested to build various partnerships with PAs and NGOs, private corporations, community groups, and academic institutes that allow it to expand the diversity of the park activities. Third, there has been experimental exploration to achieve a financially self-sufficient model by establishing internal revenue models and hence allow the reduction of reliance on public finances. The result of this type of park management would allow for improving park quality and make the park space a vital part of the local economy. Fourth, the strategies for a local community's participation are needed to allow the community to become a producer as well as a consumer. This study shows that the direction and significance of the park governance model regarding the fact that the plans sought by the two parks are extending the layout of public-centered discussion to the private sector and the third non-governmental sector including to the local community group. This shows both implications and limitations, such as the risk of privatization through non-governmental activities at the park or the violation of essential functions as a public good due to a profit-generating management policy for securing financial self-sufficiency. At the current point in which plans are under way for the development and management of large parks, a park governance model requires continuous study and expansion of discussion in the future.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.9
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• pp.441-450
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• 2016

In this study, we investigate the effect of the level of cognitive affordance which explains an explicit interaction method on the interest of viewers. Viewer's recognition of the interaction method is associated with cognitive affordance as a matter of visual-perceptual exposure of the input device and viewer's cognition of it. The final goal of the research on affordance is to enhance the audience participation rather than the smooth interation. Many interactive media artworks have been designed with hiding the explicit explanation to the artwork due to worry that the explicit explanation may also hinder the induction of impressions leading the viewer to an aesthetic experience and the retainment of interest. In this context, we set up two hypotheses for study on cognitive affordance. First, the more explicit the explanation of interaction method is, the higher the viewer' understanding of interaction method is. Second, the more explicit the explanation of interaction method is, the lower the interest of the viewer is. An interactive media art work was manufactured with three versions which vary in the degree of visual-perceptual information suggestion and we analyzed the participation and interest level of audience in each version. As a result of the experiments, the version with high explicitness of interaction was found to have long time spent on watching and high participation and interest of viewers. On the contrary, the version with an unexplicit interaction method was found to have low interest and satisfaction of viewers. Therefore, regarding usability, the hypothesis that a more explicit explanation of interaction would lower the curiosity and interest in exploration of the viewer was dismissed. It was confirmed that improvement of cognitive affordance raised the interaction of the work of art and interest of the viewer in the proposed interactive content. This study implies that interactive media art work should be designed in view of that the interaction and interest of audience can be lowered when cognitive affordance is low.