• Journal of the Korean earth science society
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• 제34권6호
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• pp.479-491
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• 2013

Products of the eruption of Mt. Baekdusan are identified as volcanic materials at the estuaries of the Songhuagang river to north, the Dumangang river to east and the Amnokgang river to west. More speficially, pyroclastic flows, lahars and volcanic floods can affect an area of 400km in radius, centering around Lake Cheonji caldera. However, unlike the millenium eruption, the flow situation has been changed. Because multi-purpose dams and reserviors with a combined pondage of mora than 2 billion tons of water have been built in the rivers of which sources are originated from Lake Cheonji caldera. In addition, the flow of fluids expected to take place when the volcano has erupted is thought to be affected by artificial constructions in both direct and indirect ways. This study calculates the direction of fluids flow by using numerical analyses of pyroclastic flows, lahars and volcanic floods that can occur when the volcano of Mt. Baekdusan has erupted. We also estimate the scope of damages by pyroclastic flows, lahars, volcanic flooding caused by the pondage of the dams and water storages in and around Mt. Baekdusan. Pyroclastic flows transported over the steep slopes at the early times of eruptions move over the mountain slopes, affecting airplanes, and lahars due to leaks of Lake Cheonji could reach as far as major rivers and streams near Mt. Baekdusan. Unlike historical accounts, volcanic flood is expected to be limited in its scope of influence to reservoirs bigger than Lake Cheonji in pondage.

• The Korean Journal of Pesticide Science
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• 제9권2호
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• pp.159-165
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• 2005

A sensitive derivatization method by using the TFE/TFAA as derivative reagent is proposed for the determination of acidic herbicides in water, by using this method, method detection limits are improved by 10 times and sample volumes are decreased by 5 times compared with other methods such as U.S. EPA and SPEED 98. And also, in order to suggest higher creditable standard operating procedure (SOP), intra- and inter-lab validation test carried out by four laboratories include our lab. The results of intra and inter-lab validations in same experimental conditions show good linearity in given range of concentrations as a $0.1{\sim}10.0$ ng/ml, and range of accuracies and precisions show $-20.5{\sim}12.2$ bias%, $0.55{\sim}24.48%$ (for intra-lab validation) and $-6.66{\sim}0.80 bias%$, $1.92{\sim}13.86%$ (for inter-lab validation), respectively.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• 제30권2호
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• pp.205-212
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• 2020

Objectives: The purpose of this study was to identify the needs and improvement measures of the risk assessment system through a survey of asbestos abatement companies. Methods: This study prepared a questionnaire that includes improvement measures for the risk assessment system(six questions) and the necessity of a risk assessment system for asbestos abatement(one question). The questionnaire was sent to 2,170 asbestos abatement companies and returned by 83 companies(return rate = 3.8%). We conducted frequency analysis, ANOVA, and Chi-squared testing at the 5% significance level. Results: This study analyzed the survey results and identified six main opinions on the risk assessment system and improvement measures. First, giving an advantage to companies with a high grade(S and A grades) in public bidding and/or qualification screening showed a similar preference(agree: 50.6%, disagree: 49.4%). Second, 57.6% of the respondents wanted to allow air showers along with water showers for low risk asbestos work. However, 23.2% of the respondents asserted that only a water shower should be allowed since there is no scientific evidence supporting the removal of asbestos by air shower. Third, in order to prevent missing the enrollment of workers, simply submitting a change report should be allowed when any worker is changed (40.0%). Fourth, 43% of the respondents answered that they did not know how to calculate the proper number of negative pressure units. The reasons given were a lack of guidelines or standards(38.9%), inconvenience (36.1%), and absence of education(25%). Fifth, the respondents who were favorable toward the necessity of a risk assessment system gave higher scores compared to unfavorable respondents on the necessity of the management of workers' work history(favorable respondent = 3.96 out of 5, unfavorable respondent = 2.68) and the necessity of professional training for workers(favorable respondent = 3.71, unfavorable respondent = 2.56). Finally, the respondents favorable toward a risk assessment system showed higher scores on the awareness of calculating the proper number of negative pressure units(4.79) compared to unfavorable respondents(3.3). Conclusions: The opinions of asbestos abatement companies identified through the survey in this study can be usefully utilized as fundamental information to improve the risk assessment system.

• Parasites, Hosts and Diseases
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• 제53권5호
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• pp.535-543
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• 2015

Integrated control strategies are important for sustainable control of schistosomiasis and soil-transmitted helminthiasis, despite their challenges for their effective implementation. With the support of Good Neighbors International in collaboration with National Institute of Medical Research, Mwanza, Tanzania, integrated control applying mass drug administration (MDA), health education using PHAST, and improved safe water supply has been implemented on Kome Island over 5 years for controlling schistosomiasis and soil-transmitted helminths (STHs). Baseline surveys for schistosomiasis and STHs was conducted before implementation of any integrated control strategies, followed by 4 cross-sectional follow-up surveys on randomly selected samples of schoolchildren and adults in 10 primary schools and 8 villages, respectively, on Kome islands. Those follow-up surveys were conducted for impact evaluation after introduction of control strategies interventions in the study area. Five rounds of MDA have been implemented from 2009 along with PHAST and improved water supply with pumped wells as other control strategies for complementing MDA. A remarkable steady decline of schistosomiasis and STHs was observed from 2009 to 2012 with significant trends in their prevalence decline, and thereafter infection rate has remained at a low sustainable control. By the third follow-up survey in 2012, Schistosoma mansoni infection prevalence was reduced by 90.5% and hookworm by 93.3% among schoolchildren while in adults the corresponding reduction was 83.2% and 56.9%, respectively. Integrated control strategies have successfully reduced S. mansoni and STH infection status to a lower level. This study further suggests that monitoring and evaluation is a crucial component of any large-scale STH and schistosomiasis intervention.

• Journal of the Korean Association of Geographic Information Studies
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• 제25권4호
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• pp.81-93
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• 2022

There are many natural hot springs and mineral springs as well as the cultural heritage of the three kingdoms period in the Geum River basin including Chungcheong region. No specific regeneration and publicity plans for deteriorated facilities in this area has been presented. This study aims to suggest promising hot spots and complex water culture belt in the Chungcheong region and Geum River basin through the spatial interpretation of resources. The northern part of the Geum River basin is expected to become a therapeutic spring belt with many hot springs and CO₂-rich springs. In the central and southern parts of the Geum River basin, it is considered that it will be possible to promote convergence publicity by using groundwater resources and cultural assets.

• Journal of Practical Agriculture & Fisheries Research
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• 제24권4호
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• pp.53-61
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• 2022

Growing agricultural products in greenhouses controlled by creating suitable climatic conditions and root zone of crop has been an important research and application subject. Appropriate environmental conditions in greenhouse are necessary for optimum plant growth improved crop yields. This study aimed to establish web-based remote monitoring system which monitors crops growth environment and status of crop on a real-time basis by applying to greenhouses IT technology connecting greenhouse equipment such as temperature sensors, soil sensors, crop sensors and camera. The measuring items were air temperature, relative humidity, solar radiation, CO₂ concentration, EC and pH of nutrient solution, medium temperature, EC of medium, water content of medium, leaf temperature, sap flow, stem diameter, fruit diameter, etc. The developed greenhouse monitoring system was composed of the network system, the data collecting device with sensors, and cameras. Remote monitoring system was implemented in a server/client environment. Information on greenhouse environment and crops is stored in a database. Items on growth and environment is extracted from stored information, could be compared and analyzed. So, A integrated monitoring system for smart greenhouse would be use in application practice and understanding the environment and crop growth for smart greenhouse management. sap flow, stem diameter and pant-water relations

• Journal of the Korean association of regional geographers
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• 제18권4호
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• pp.473-493
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• 2012

Malaria infection is sensitively influenced by regional meteorological conditions along with global climate change. Remote sensing techniques have become an important tool for extraction of climatic and environmental factors, including rainfall, temperature, surface water, soil moisture, and land use, which are directly linked to the habitat qualities of malaria mosquitoes. Improvement of sensor fidelity with higher spatial and spectral resolution, new multinational sensor development, and decreased data cost have nurtured diverse remote sensing applications in malaria research. In 1984, eradication of endemic malaria was declared in Korea, but reemergence of malaria was reported in mid-1990s. Considering constant changes in malaria cases since 2000, the epidemiological management of the disease needs careful monitoring. Geographically, northmost counties neighboring North Korea have been ranked high in the number of malaria cases. High infection rates in these areas drew special attention and led to a hypothesis that malaria dispersion in these border counties might be caused by north-origin, malaria-bearing adult mosquitoes. Habitat conditions of malaria mosquitoes are important parameters for prediction of the vector abundance. However, it should be realized that malaria infection and transmission is a complex mechanism, where non-environmental factors, including human behavior, demographic structure, landscape structure, and spatial relationships between human residence and the vector habitats, are also significant considerations in the framework of medical geography.

• Journal of the Korean Association of Geographic Information Studies
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• 제6권1호
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• pp.119-131
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• 2003

Rainfall-runoff process is under the control of hydrologic parameters having temporal and spatial variety. Accordingly, it is difficult to efficiently deal them since many parameters and various information are required to perform hydrologic simulation. So the purposes of this study is to estimate the runoff volume by frequency using GIS techniques and NRCS method. The analysis of frequency rainfall is analyzed using FARD 2002 program and the result of goodness of fit test show that Log-pearson type III is suitable distribute type for the applied area. TOPAZ program used for the analysis of DEM data examining into geological characteristic. NRCS curve numbers estimated using landuse map and soil map for the estimation of effective rain fall in the basin. The storm Type II and Type III were used as the type for the application of NRCS. The result of application show that the runoff volumes above 80 years frequency in return period have similar patterns regardless of Type II and Type III. In addition, the results of comparison with runoff volumes by frequency in the report of river improvement master plan show that it have similar volumes as the relative errors for them of 80, 100 years frequency are each 7.65%, 5.33%.

• Journal of Wetlands Research
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• 제22권4호
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• pp.225-238
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• 2020

The agricultural landscape is considered an important space to provide service functions, but the reality is that environmental and ecological problems are being reported in the creation of a facility horticulture complex. Therefore, this study was conducted to contribute to sustainable agriculture by creating a more eco-friendly facility horticultural complex. The elements of planning for eco-friendly development of the facility horticultural complex were derived from literature and expert surveys. The master plan and the bird's-eye view were then applied to the Saemangeum area by applying the planning elements. After analyzing the method of selecting and deploying input elements for improving functions, it was suggested that low-flow areas, wetlands, artificial storage facilities, green spaces, and waterways should be placed in harmony with the landscape and that the building-to-land ratio should be applied at 55%. The final design was prepared by applying the ecological service function improvement plan proposed by experts. The final bird's-eye view also reflected water purification facilities, connection of wetlands to waterways, packing of pitchers, and connection of green areas. The results of the research are expected to be used as basic data for policy and budget allocation for the eco-friendly creation of horticulture facilities and contribute to sustainable agriculture by contributing to national biodiversity and environmental preservation.

• Korean Journal of Environmental Biology
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• 제39권2호
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• pp.225-235
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• 2021

To attain the long-term benefits of forest restoration in North Korea, it is important to present the economic value of reforestation. This study as aimed to evaluate the economic value based on cost-benefit analysis from the ecosystem services perspective. The benefits of reforestation were classified into ecosystem services such as carbon sequestration, water supply, soil erosion control, and disaster risk reduction, and were converted into economic values to calculate comprehensive benefits. In the forest restoration scenario, an "independent forest restoration scenario (IFS)" and a "cooperation-based forest restoration scenario (CFS)" were composed in consideration of recent afforestation performance and forest policy, and the difference in the quantity of afforestation was derived as a scenario despite the same restoration period. In the IFS, it is estimated that over the next two decades, 800 thousand ha of the forest will be restored at a cost of KRW 3,829 billion, resulting in a benefit of KRW 6.87 trillion. The present benefit net value is KRW 3,39 trillion. In the CFS, it is estimated that the benefits of KRW 18,890 billion will be generated by restoring 2.2 million ha of the forest at a cost of KRW 10,053 billion. The present benefit net value is KRW 8,359 billion. In both scenarios, BCR had an economic feasibility value greater than 1, but there was a big difference in the expected benefits. In conclusion, forest restoration can have higher benefits than cost, and its value could be enhanced through forest cooperation.