• 한국동물위생학회지
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• 제35권3호
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• pp.183-189
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• 2012

Tsutsugamushi disease or scrub typhus cause by Orientia tsutsugamushi is an endemic disease in Korea. Chigger mites and field rodents play roles in transmission of the disease by the vector and host of the agent. The purpose of this study is to investigate the density of the chigger mites and field rodents due to environmental factors such as temperature, relative humidity, soil thickness and the various vegetations to the 9 field rodent collection sites. The total 62 field rodents was captured by the Sherman collapsible traps from April to October 2009 at the Jangseong of Jeonnam Province, Korea. The trapping rate of the field rodents by the different collecting sites was dominant at subside storage water (24%), bush near by dam (22%), bank around field (20%), followed by 18% of grassy field and surround cattle shed. The distribution of chigger mites by the different collecting sites was the highest at Bush near by dam (28.7%). And the sites of subside storage water, bank around field and surround cattle shed were 20.4%, 18.8%, 16.4%, respectively. On the other hand the collecting sites of stream bank and ridges between rice paddies were not collected. The temperature to the collecting sites was showed $24.1^{\circ}C$ in June and $24.2^{\circ}C$ in October which was higher than April ($10.6^{\circ}C$), whereas lower than May ($25.3^{\circ}C$) and September ($26.8^{\circ}C$). The highest number of mites was collected at $24.2^{\circ}C$ and 46.6% relative humidity in October. The chigger mites and field rodents were highly collected between 18 and 24% at the sites where are loosely in the superficial layers of the soil from 8.0 cm to 10.2 cm. Total 25 species of vegetation were distributed at the collecting sites. In the present study, strong evidence was found that bank around field and grassy field were provided for the prevalence sites of tsutsugamushi disease.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.991-996
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• 2014

Power frequency magnetic field is still a critical problem for new construction of overhead power transmission lines in Korea because most people have been concerned about possibly carcinogenic effects of it. Although reference level of power frequency(60Hz) magnetic field has been set to 200uT in ICNIRP guidelines published in 2010, Korean government has no intention of adjusting 83.3uT specified by law in 2006 to this new reference level in consideration of people's concerns for the time being. Regardless of the current regulated magnetic field value, electric utility company has been trying to reduce magnetic field in the residential area in the vicinity of overhead power transmission lines to take into account of public concerns on the long-term effect of magnetic fields. In an effort to reduce magnetic field, engineering side has made considerable efforts to develop passive loop based, cost-effective mitigation technique of power frequency magnetic field more than ten years. In order to verify developed power frequency magnetic field mitigation technique based on passive loop, a horizontal type of passive loop was designed and installed for commercially operating 154kV overhead power transmission line for the first time in Korea. The measurement results before and after the installation of passive loop showed that magnetic field could be reduced to about 20%. The electrical environmental effects such as AN, RI and TVI were assessed before and after the installation of passive loop and these values were complied with the requirements specified by electric utility. It has been confirmed from the field test results that passive loop could be commercially and cost-effectively utilized to mitigate power frequency magnetic field.

• 환경영향평가
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• 제21권3호
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• pp.417-429
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• 2012

In this study, a diagnostic wind model, CALMET and a micrometeorological numerical model, ENVI-MET were used to analyze the wind field in and out of the site designated for the industrial complex around Buron-myeon, Wonju, Gangwon-do. The results of modeling with CALMET showed that the air flow in industrial complex was little affected by the surrounding terrain. And the result of wind field analysis with ENVI-MET showed there are turbulent air flows such as cavity and wake around structures in the industrial complex, which can cause high-air pollution. Therefore, it is necessary to design the industrial complex considering the wind path according to wind directions.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1468-1475
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• 2005

In this study, the effects of temperature on loading of long-span strut were studied by using field monitoring and numerical analysis. For the field monitoring, several sensors, such as stain gages, temperature gages and load cells, were installed on the struts. From the monitoring results, the relation between temperature and axial force of the struts was analysed. By numerical analysis, the changes of axial force of strut and lateral displacement of wall due to temperature change were described with the strut length and ground conditions.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.897-903
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• 2004

Waste lime used in this study is producted as a by-product in the manufacturing process of making $Na_2CO_3$ from local chemical factory in Incheon. Currently about 320 millon tons of waste lime are accumulated and annually 100,000 tons are producted. Reuse of waste lime mixed with soil for banking and backfill materia in civil works was analysed in this study. This study was Carried out to investigate the geotechnical and environmental characteristics on field application. Field investigations were conducted on the road construction site in Incheon. This study presents the results of the engineering characteristics in field test and the leaching characteristic of waste lime in laboratory column tests. Countermeasure for reduction of environmental effects was suggested from the test results.

• 한국환경복원기술학회지
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• 제11권4호
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• pp.57-66
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• 2008

This study, with teachers form elementary schools in Chungju-si as its subjects, has investigated influence of school forest on satisfaction with school greenspace and environmental education. It has reached the following conclusions. As for recognition of and satisfaction of school greenspace there were meaningful differences between teachers form school forest model schools and ones from common schools, which was thought to be due to positive effects of school forest movement. It appeared that environmental education was carried out through audio-visual materials once a week in most schools. On the other hand, as for class places, 'classroom in parallel with outdoor class' and 'classroom education' appeared to be carried out most frequently in the case of school forest model schools, and 'classroom education' in the case of common schools. However, considering the fact that 'field learning' the most important element in environmental education, appeared to be carried out least frequently in both of the groups, which suggests that we should improve it for future through introduction of various field-experience learning programs. As a result of the survey of satisfaction with environmental education, some meaningful differences were recognized between school forest schools and common schools, and 'presence or absence of field learning spaces' was the most frequently answered reason for 'satisfied' and 'unsatisfied'. Thus, 'schools' and related institutions' enthusiastic efforts are needed for providing field-experience spaces where children can directly access to and explore into nature.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2002년도 봄 학술발표대회 발표논문집
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• pp.159-162
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• 2002

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.442-451
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• 2008

The evaluation of field degree of consolidation on soft clays has been an important problem in geotechnical areas. Monitoring either settlements or pore water pressures has been widely applied in the filed, but occasionally they have some problems. This study addresses the suggestion and application of another method for evaluating the degree of consolidation using shear wave velocities. A research site where soft clay layers were consolidated by surcharging loads was chosen. Laboratory tests were performed to determine the relation between shear wave velocity and effective stress. Field seismic tests were conducted several times during the consolidation of the clay layers. The tests results show that the shear wave velocity increased significantly as clays consolidated. The shear wave velocities at each field stress states were derived from the laboratory results and the degree of consolidation was evaluated by comparing the shear wave velocities obtained by laboratory and field seismic methods. In most stress states, the degree of consolidation evaluated using the shear wave velocity matched well with that obtained from field settlement record, showing the potential of applying the method using shear waves in the evaluation of field degree of consolidation on soft clay deposits.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.502-508
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• 2005

In order to assess the environmental risk of pesticides, information is usually required on the likelihood of exposure of organisms to the constituents of pesticides, expressed as a predicted environmental concentrations (PECs) and the likely effects of the constituents of pesticides on aquatic and terrestrial organisms, expressed as a predicted no-effect concentrations (PNECs). In this paper, the pesticide fate model, RICEWQ alone and coupled with the pesticide movement model, RIVWQ was used to simulate the potential for predicting the environmental concentrations of pesticides in paddy fields and adjacent surface water systems. The RICEWQ model was successfully calibrated against field data in poinding depth for paddy field. For the assessment of importance for water and pesticide management conditions and field scales, the integrated RICEWQ-RIVWQ model was simulated by the scenario analysis. The results of this study can be used as a basic information for assessing the environmental risk of pesticides.

• 한국응용과학기술학회지
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• 제31권1호
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• pp.59-65
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• 2014

Indoor air quality including metro subway is of recent interests in large cities. Inflow air to the inside of the train and circulating air flow through MVAC of stations contain large amount of iron based fine particles. This paper evaluated the collection of such a dust by magnetic filters as comparing to conventional particle capturing mechanisms such as inertia, direct impaction and diffusion. It was found that filtration velocity, magnetic field intensity, and fiber size were the most important parameters for magnetic filtration. Application of magnetic force obviously enhances the collection efficiency particularly in fine modes smaller than 10 mm. However, its effect was found greater in 2.5 mm than submicron particles.