• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1126-1135
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• 2012

In order to produce high-quality fermenting composts, bacteria strains with high activities of extracellular enzymes (cellulase, chitinase, amylase, protease and lipase) were isolated from the soils in 6 provinces of Korea, and characterized by 16S rRNA gene sequence analysis and properties. The selected 7 stains inoculated to livestock manure for 2' fermenting time, and experimental treatment divided into 3 groups, B1, B2 and B3, according to microbial activity and enzyme type. Our results showed that microbe applications (B1, B2 and B3) can increase (p<0.05) both rhizomes (17-38%) and enzyme activities (50-81%) in compost after fermenting time, respectively, compared to non-microbe treatment (control). The microbe application also decreased significantly (p<0.05) the $NH_3$ and $H_2S$ gas contents 13.4 and 27.3% compared with control, and the Propionic acid and Butyric acid gas contents 14.5 and 19.6%, respectively, as compared to the control. The microbial degradation rate (%) of pesticides and heavy metals increased significantly (p<0.05) after fermenting time, respectively, as compared to the control. Especially, microbe applications were more effective in total rhizomes yields and bioactivities than non-microbe treatment. Thus the results of this study could help in development of potential bioinoculants and composting techniques that maybe suitable for crop production, and protectable for earth environment under various conditions.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.139-150
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• 2007

As computer technology has been rapidly advanced, geographic information system (GIS) is recently used in many disciplines. In this study, for a model area in Seoul, seismic hazard potential relating to site effects, which are influenced by the subsurface geotechnical conditions, was estimated using the GIS tool. The distribution of pre-existing borehole drilling data in Seoul metropolitan area was examined for the regional estimation of site-specific seismic responses at the model area. Spatial geo-layers across the entire model area were predicted by constructing a GIS-based geotechnical information system (GTIS). A microzonation of site period $(T_G)$ for estimating site-specific seismic responses at the model area was performed within the GTIS. The spatial microzoning map of $T_G$ indicated seismic vulnerability of two- to four-storied buildings in the model area. Furthermore, a site classification map for determining the design ground motion was established based on the $T_G$ within the GTIS. This informed that most of location in the model area was categorized into current site classes C and D. This seismic microzonation framework for the model area could be applicable particularly in the entire Seoul metropolitan area based on the pre-existing borehole data.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.1
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• pp.52-59
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• 2007

A field mill capable of measuring the magnitude and polarity of electric fields at the ground level was studied to apply to a lightning warning system as a sensor. We designed and fabricated a planar-shutter type field mill with a rotating-vanes. A calibration of the field mill was performed in a vertically symmetrical arrangement which consists of two equal size parallel round plates to form a homogeneous electrical fields. The sensitivity of the field mill was adjusted at 0.5[V/kV/m], and this covers a ranges from 200[V/m] to 20[kV/m]. After the calibration experiment, the field mill was installed on the roof of a building to measure the changes of electric field intensity caused by thunderclouds. During the period from July 1. 2006 to July 15. 2006, the electric field intensity was recorded a ranges of $+2[kV/m]{\sim}-6[kV/m]$ depending on generation, extinction and movement of thunderclouds. From the actual test on the ground it is confirmed that the field mill has a good performance necessary for the measurement of DC electric fields.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.2
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• pp.194-205
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• 2006

The purpose of this study is to develop a pedestrian multi-agent model and simulation system using multi-agent theory, which may be utilized as a planning support system for building a comfort and safe environment of pedestrian street. Differing from existing pedestrian models, however, every single pedestrian was regarded as an individual agent in the model. Multiple agents like multiple pedestrians in the street then maintain their own characteristics and respond to surrounding environment. In addition their moving behavior are made by their own decision rules that they have or had acquired through the interactive communications or learning between agents like real world. After verifying the model validation, as the $R^2$ between the predicted value and observed value was up to 0.781, the developed model was applied to Gazwa district within Gyeongsang university village. The simulation system was developed by Flash MX action scripts and the physical environment of the streets was configured with the digital map and ArcGis within computer virtual space. The attribute data of buildings such as type and size of commercial business were collected through the field survey and combined with physical features. Then the effect of the variation of building attractiveness and the occurrence of street events to pedestrian environment were simulated. Through the experiments this study could make suggestions to improve pedestrian environment.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.2
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• pp.84-93
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• 2011

In order to provide the real time and proper information to the pedestrian who is using the transport connection and transfer center through data collecting and processing process, the design of the test-bed (Gimpo airport)'s communication construction and the technology of the pedestrian location tracking has been researched. The design of the communication construction should make sure that it can provide believable data to the user of the transfer center. At the same time, the location tracking should also be considered, so that the require of the communication efficiency and the location tracking efficiency can be met together. In order to make the efficient location tracking technology, the problems related to the commercial technology based real time location identification will be resolved and the new approach method was proposed and be applied and analysed to the test-bed. The wireless access points can be located in the most real-world situation which has added the characteristics of the real building to the electronic map, and through the analysis of theirs location, they can be set as the mainly necessary points for the communication construction design and the location tracking and the method to locate that points has been proposed. How to set, how to apply it to the test-bed and the examination result will be introduced in this paper.

• Journal of the Korean Geographical Society
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• v.41 no.6 s.117
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• pp.682-700
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• 2006

This study aims to show a model of environmental planning towards sustainable science parks. For the purpose of this study, an analysis of the environment of green space at sustainable science parks as pertaining to environmental soundness, ecological stability and landscape aesthetics is applied as a case study to Osong Bio-Health Science Technopolis, a developmental promoted district. Considering the factors resulting from Habitat Agenda(II) and other preceding studies, this study derives fifteen elements of environmental planning for sustainable science parks. A questionnaire/survey was conducted with relation to these fifteen elements to officials who would be moved to Osong Bio-Health Science Technopolis. From this survey, it is shown that respondents have a strong awareness that for the sustainable environment of a science park, the park should preserve as much green space as possible, and that the park should be in harmony with the surrounding natural environment. The practice of forestation at sustainable science parks not only develops a healthy environment that promotes an image of green, but also promotes a stable ecological system. As such, this study suggests alternatives to environmental planning from the perspective of landscape ecology by assessing the project of developing Osong Bio-Health Science Technopolis. To continuously maintain landscape aesthetics, one needs to control the height of buildings, lest the forests should be hidden by the buildings.

• Journal of the Korean GEO-environmental Society
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• v.10 no.2
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• pp.21-28
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• 2009

A grouting method has been widely used in construction of large-scale structure to reduce permeability and reinforce the ground. If cement and grout material were not mixed well in the injection tip equipment, an opposite flow and interception state of the chemical grouting can occur. McG (Multi-mixing counterflow prevented Grouting, McG) method installed a special grouting device to allow better mixing of the grouting material(above fineness $6,000cm^2/g$) and prevent backward flow. The block of nozzle also diversify powder rate of cement. YSS (Youngil Special Silicate, YSS) that lowers $Na_2O$ and thereby increases durability was developed by gel-forming reaction material. The seepage state and unconfined compressive strength of the injection material using the special injection tip equipment was tested in this study. The results of this study showed that the uniaxial compressive strength, permeability, N-value, TCR and RQD were improved by this method. Engineering characteristics obtained by the special injection tip method will be compared with those by the other method through various field tests from now on.

• Journal of The Korean Association of Information Education
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• v.21 no.2
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• pp.199-208
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• 2017

The present study investigates the potential of an educational programming game as a strategy for enhancing effective domains of mathematics curriculum, which has been criticized as a problem of education in Korea. The process of programming Fortress, an educational game, in conjunction with the lesson on the trigonometric function as part of the middle school mathematics curriculum, was designed for instruction and learning, and its effectiveness was tested. The study was conducted using a nonequivalent pretest-posttest experimental design. Research procedures included the following steps: (1) both the experimental and the comparison groups participated in four classes to understand and apply the concept of the trigonometric function, and (2) the experimental group participated in Fortress game programming activities using Scratch, which was designed in this study, while the comparison group participated in solving a real-life trigonometric problem - calculating the height of a building using the concept of trigonometry. The results of the t-test showed that students' interest and perceived value of the mathematics curriculum were significantly higher in the experimental group than in the comparison group. However, the results of analysis of covariance (ANCOVA) using pretest scores of the interest and perceived value showed the influence of pretest scores on posttest scores for the interest level, although the effect of the experiment on the perceived value of the mathematics curriculum was more significant.

• Fire Science and Engineering
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• v.15 no.1
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• pp.100-107
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• 2001

A Interior material, a main cause of fire-growth and generating toxic gas when it burns, should be dealt with great care in life safety design. Nonetheless, it has been used recklessly with undue attention to its contribution to fire in particular in entertainment occupancy and causes many victims in fire. Therefore, this study attempts to examine the current use of interior material in Korea and find out what to be improved and enhanced in terms of related regulations. Based on the comparison and analysis of the Korea regulation with those of advanced nations, suggestions are made for an effective and efficient improvement and complement to the current system. What can be suggested from this study are as follows. The use of interior material should be controlled under the unified regulation of fire-safety codes. Code should be set up so that the current construction enforcement should be applied in retroactive to those entertainment buildings that obtained a license prior to the implementation of the system certifying that the building is fire-resistant and fire-protective. The legislation should be made to control the fire-protection facilities of small-sized, underground entertainments. It should be obliged to present the blueprint displaying the use of interior material at the time of changing occupancy. Or, it should be compelled to report changes that go way without permit to the administrative office. A compulsory provision should be set up to have a fire-resistant performance to movable furniture. The classification index designating the fire hazard of interior material by flame spread rate and smoke toxicity and its test method should be established.

• Journal of the Korea Concrete Institute
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• v.24 no.5
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• pp.585-596
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• 2012

In this study, the flexural characteristics of reinforced polymer concrete T-beams strengthened with GFRP, typically used for bridges and parking structures, are investigated. A method to determine the flexural failure mode of reinforced polymer concrete T-beams comprised of compression failure (CF), tension failure (TF), and fiber sheet failure (FF) for different levels of GFRP strengthening is proposed. Moreover, the present study provides a formula to calculate the design flexural strength for each failure mode. In reinforced polymer concrete T-beams strengthened with GFRP, an ideal failure mode can be achieved when the failure occurs in the following order: 1) yield of steel reinforcement, 2) failure of GFRP, and 3) compression failure of concrete. In the case of FF mode, due to GFRP failure before the polymer concrete crushing in compression region, a concept of equivalent rectangular block based on the ultimate limit state of concrete should not be used. Thus, this study suggests an idealized stress-strain curve for polymer concrete and finds parameters for stress block, ${\alpha}$ and ${\beta}$ based on the strain distribution in polymer concrete. Furthermore, the present study suggests an aspect ratio of 2.5 by examining the compressive stress distribution and design flexural strength characteristics for different aspect ratio of T-beams. This study also provides a design flexural strength formula, and validates its acceptability based on experiment and theoretical analysis.