• Hwankyungkyoyuk
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• v.7 no.1
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• pp.88-105
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• 1994

Since the Rio Convention of 1992, the international community has displayed a heightened consciousness concerning the Earth environment and domestic attention on the said subject has also rapidly increased. An Ecological life style signifies the conscious efforts to preserve the environment interpreted into quotidien action. For the realization of conservation in action, an understanding of the specific details of environmental preservation must precede. The environmental conservation action in the homes was systematically approached in this study as an input-process-output and feedback cycle. The input phage is the consumer oriented buying stage, the while the process is the actual use of the products and the output stage consists of categorizing and producing wales, the feodbach being recycling of resources. At each stage the attitude which is devoted to environmental consciousness plays a big ride in the actual preservation of the Earth environment. in order to effectively conserve the environment, efforts displayed by the business sector is as important as implementation of environmentally conscious action at home. During the process of producing and distributing products, and attitude and action in preservation efforts are crncial and the responsibility ageat. For the business sector to effectively initiate environmental preservation into action, institutional support from the government and cooperation from the homes is of essence. Consolidated efforts to atter the superfrony life style into ecological life styles and ralues is essential to solve the most important socio-economic issue of the 90's of preserving the earth.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.874-882
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• 2009

Continuous monitoring of dam performance is essential to earth and rockfill dams safety because it has to be guaranteed for safety during construction period of course and from initial impounding to a long term maintenance period of dam. Among the 31 dams managed by Kwater at present, the proportion of dams being over 20 years after completion of construction is 42% and it is estimated that the loss rate of monitoring devices will be increase as times. Monitoring devices would be impossible to repair since those are mostly installed in the dam body and foundation. If repairing of monitoring devices is possible, the expenditure will be expensive. Therefore reasonable decision making for abandonment, repair and alternation for loss of monitoring devices would be needed through the establishment of key instrument for earth and rockfill dam safety. In this study the process of monitoring for safety were modeled by failure modes of dams, adverse conditions related to failure mode, indicators of adverse condition and monitoring devices The relationship between failure mode and monitoring devices were systematically analyzed and established and evaluation technique for qualifying the importance of monitoring devices were presented.

• Journal of the Korean GEO-environmental Society
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• v.11 no.2
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• pp.53-60
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• 2010

Considering environmental issues and lack of space, it is a necessity to minimize the amount of excavation. Various types of excavation methods are being used in practice. This study proposes a reasonable method for estimating the earth pressure acting on a reinforced wall in front of a excavated slope. The measured data in the field and numerical analyses were used. Results of the study shows that the earth pressure acting on the excavated wall is less than that estimated by Rankine's equations. It was shown that when the excavated slope is used with the reinforced wall, the pressures acting on the reinforced wall can be greatly reduced.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.5
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• pp.58-64
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• 2012

In electric power supply systems, an earthing system determines the electric potential of the conductors related to that of the Earth's surface. The choice of earthing system has implications for the safety of the power supply systems. There are considerably different regulations for earthing (grounding) systems in each country. A protective earth(PE) conductor ensures that all exposed conductive surfaces are at the same electric potential as the earth surface. This paper deals with that when PEN conductor of TN-C-S system is disconnected, dangerous touch voltage causes personnel body to be harmed and human being's property to be damaged seriously. For this reason, this paper explains how serious problems can occur when the fault current flows. As a consequence, we can understand how we can design earthing system properly to ensure the personnel safety against earth faults. The result shows the way that TN-C-S system can be applied safely in Korea.

• Journal of the Korean Professional Engineers Association
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• v.33 no.3
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• pp.35-36
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• 2000

The waste management system has become social problem all over the world since it is too much to control the waste generated during the economic development. Therefore Human being should minimize the dispersion of useful materials on the earth which is limited by means of recycle and reuse, and should maximize the use of solar energy which is almost infinite.

• Journal of Korea Spatial Information System Society
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• v.12 no.1
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• pp.66-75
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• 2010

The authors argues that the current road updating system based on traditional aerial photograph or multi-spectral satellite image appears to be non-user friendly due to lack of the frequent cartographic representation for the new construction sites. Google Earth are currently being emerged as one of important places to extract road features since the RGB satellite image with high multi-temporal resolution can be accessed freely over large areas. This paper is primarily intended to evaluate optimal threshold of RGB pixel values to extract road features from Google Earth. An empirical study for five experimental sites was conducted to confirm how a RGB picture provided Google Earth can be used to extact the road feature. The results indicate that optimal threshold of RGB pixel values to extract road features was identified as 126, 125, 127 for manual operation which corresponds to 25%, 30%, 19%. Also, it was found that display scale difference of Google Earth was not very influential in tracking required RGB pixel value. As a result the 61cm resolution of Quickbird RGB data has shown the potential to realistically identified the major type of road feature by large scale spatial precision while the typical algorithm revealed successfully the area-wide optimal threshold of RGB pixel for road appeared in the study area.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.1
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• pp.1-12
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• 2023

The purpose of this study is to investigate earth science pre-service teachers' perceptions and educational utilization of geoparks. It is intended to provide implications of geopark education in the current curriculum and effective geopark education. Education using geoparks has the effect of helping students cultivate inquiry and learning skills, enhancing students' participation in classes. To provide education with these results, it is necessary to deliver meanings of the geopark education to of earth science pre-service teachers who will educate future generations. However, despite the advantages and needs of geopark education, earth science pre-service teachers lack an understanding of geoparks. In this study, 56 pre-service teachers enrolled in earth science education at a university in Gyeongsangbuk-do were investigated for: their perception levels of geoparks, experience, necessity, and learning method of geopark education. As a result, earth science pre-service teachers were well aware of the geoparks, but they lacked knowledge of domestic and global geoparks, confirming the need for geopark education. Currently, the degree of geopark education in the secondary curriculum is insufficient, and earth science pre-service teachers feel the need for it. However, since the understanding of geopark is lacking, support for geopark education is needed. Earth science pre-service teachers being positive about the need for geopark education, it is expected that geopark education will be active in the field of earth science, social, and comparison education when they become teachers in the future.

• Journal of the Korean earth science society
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• v.26 no.4
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• pp.347-357
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• 2005

Since 1998, an elementary teacher education institute in Korea has hosted the center for the gifted education. The institute hired undergraduate students to escort and liaison each class of the gifted student participants with assisting classroom activities. These liaison teachers observed the gifted classroom activities and evaluated them by using a given checklist and filling out pre-made evaluation forms. Currently this system is being transferred from part-time jobs for students to earn allowance into well organized pre-service teacher program focusing on the gifted education. In other words, the purpose of system is being shifted from how liaison teachers facilitate the gifted program to how the system helps the liaison teachers to be quality teachers for the gifted who can understand what the gifted are and how to facilitate them. Analyzed were the self reports of the liaison teachers regarding their perceptions and beliefs of the gifted and their education program. It was found participant liaison teachers purposed to have more live experiences with getting along with students as well. Liaison teachers’ perceptions on establishing a gifted teacher professional education sequence were reported in this study. The potential scaffolding of the pre-service teacher education program model of the gifted education was provided as a consequence of this study.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.2
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• pp.214-224
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• 2007

A three-dimensional computational fluid dynamics (CFD) model with the renormalization group (RNG) $k-{\varepsilon}$ turbulence model is used to examine the effects of difference in building height on flow and pollutant dispersion in asymmetric street canyons. Three numerical experiments with different street canyons formed by two isolated buildings are performed. In the experiment with equal building height, a portal vortex is formed in the street canyon and a typical recirculation zone is formed behind the downwind building. In the experiment with the downwind building being higher than the upwind building, the ambient flow comes into the street canyon at the front of the downwind building and incoming flow diverges strongly in the street canyon. Hence, pollutants released therein are strongly dispersed through the lateral sides of the street canyon. In the experiment with the upwind building being higher than the downwind building, a large recirculation zone is formed behind the upwind building, which is disturbed by the downwind building. Pollutants are weakly dispersed from the street canyon and the residue concentration ratio is largest among the three experiments. This study shows that the difference in upwind and downwind building height significantly influences flow and pollutant dispersion in and around the street canyon.

• Journal of the Korean earth science society
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• v.36 no.5
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• pp.476-483
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• 2015

The high-order Laplacian-type filter, which is capable of providing isotropic and sharp cut-off filtering on the spherical domain, is essential in processing geophysical data. In this study, a spherical high-order filter was designed by combining the Fourier method with finite difference-method in the longitude and latitude, respectively. The regular grid system was employed in the filter, which has uniform angular spacing including the poles. The singularity at poles was eliminated by incorporating variable transforms and continuity-matching boundary conditions across poles. The high-order filter was assessed using the Rossby-Haurwitz wave, the observed geopotential, and observed wind field. The performance of the filter was found comparable to the filter based on the Galerkin procedure. The filter, employing the finite difference method, can be designed to give any target order of accuracy, which is an important advantage being unavailable in other methods. The computational complexity is represented with 2n-1 diagonal matrices solver with n being the target order of accuracy. Along with the availability of arbitrary target-order, it is also advantageous that the filter can adopt the reduced grid to increase computational efficiency.