• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.4
• /
• pp.2205-2209
• /
• 2016

Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern region. Active surveillance in rural communities with an appropriat low-cost screening tool is required to facilitate early detection. Therefore, this study aimed to investigate the population at risk of CCA in Bua Yai district, Nakhon Ratchasima province, Northeastern Thailand using the Korat-CCA verbal screening test (KCVST) during June to October 2015. Reliability of KCVST demonstrated a Cronbach alpha coefficient=0.75 Stepwise-multiple regression showed that alcohol consumption was important for CCA screened, followed by agriculture and pesticide use, under-cooked cyprinoid fish consumption, praziquantel use, naïve northeastern people, opisthorchiasis, family relatives with CCA, and cholangitis or cholecystitis or gallstones, respectively. Population at risk for CCA was classified to low risk (63.4%), moderate risk (33.7%), and high risk (1.32%) for CCA. When CCA was screened using ultrasonography, 4 of 32 high risk participants had an abnormal biliary tract with dilated bile ducts. This study indicates that KCVST is a potential useful too which decrease the cost of large scale CCA screening.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.32 no.5
• /
• pp.331-339
• /
• 2020

In this study, ways to reduce the edge pressure at the bottom plate of the caisson breakwater were considered. The water depth, freeboard, design wave height and period, and the location of the center of gravity on the super-structure of the breakwater were selected as key design variables that influence the edge pressure, and analyzed how the edge pressure changes according to the change of this key variables. The pressure distribution formulae suggested in the design standard was applied for the calculation of design wave forces. Based on the wave forces, the required effective self-weight of the super-structure and the minimum width of the caisson were determined to have a safety factor of 1.2 against sliding and overturning. From the results, it was found that the edge pressure rapidly increased as the water depth increased, and could exceed the allowable bearing capacity when it reached a certain water depth which is 20 m within the analysis conditions. It was also confirmed that the edge pressure gradually increased linearly as the freeboard increased, but decreased with the increase of the wave height and period. This edge pressure could be significantly reduced up to more than 20% by moving the center of gravity of the super-structure to the seaside, which is 5% of the caisson width. Based on the analysis results and the recently conducted research results, a method was proposed to reduce the edge pressure that can be used in the design.

• Journal of Korea Water Resources Association
• /
• v.53 no.12
• /
• pp.1131-1142
• /
• 2020

This study assessed evapotranspiration (ET) methods applying for estimation of paddy rice water demand based on agricultural water supply. The Modified Penman (MP) method and the Penman-Monteith (PM) method recently suggested by Rural Development Administration (RDA) were considered. The 6 Korea Rural Community Corporation (KRC) command areas located in Honam province were selected in this study. The climate characteristics were also analysed with the average annual and the growing season temperatures and rainfalls. As a result, the annual average and the growing season temperature showed the increased trend while the rainfall tended to decrease during 30 years. The paddy rice water demand found to be directly influenced by these climate trends as ET also affected by them. The higher values of paddy rice water demand were obtained from applying MP method compared to the one applying PM method. The lower differences were also obtained from MP method for the comparisons between the paddy rice water demand estimated by both methods with agricultural water supply. Therefore, these results suggest that the MP method is more desirable to use for estimating paddy rice water demand in order to achieve stability of irrigation designs and plans.

• Journal of Korea Water Resources Association
• /
• v.55 no.7
• /
• pp.531-543
• /
• 2022

Integrated water resources management (IWRM) has focused on efficient response to various water related disasters by climate change. In particular, more flexible usage of conventional water resources infrastructures is expected to provide an eco-friendly water management. Multi-purpose dams and water supply dams are well known as water management facilities for securing and supplying water in drought season. Recently, based on the report '2021 multi-purpose use of hydropower dams in Han river', contribution of hydropower dams on water resources management is becoming more significant beyond the traditional role of hydropower generation. In drought conditions, the dams control water supply depending on the pre-defined drought stages. In the case of multi-purpose dams, an operation standard during drought has been already prepared and applied; however, for the hydropower dams, specific standards are not fully prepared yet in South Korea. In this study, a method for calculation of standard water storage and discharge reduction of hydropower dams according to drought stage is newly proposed reflecting the characteristics of hydropower dams. The proposed method was applied to the hydropower dams in Han river, where six hydropower dams are located. A case study of the historical droughts occurred in 2014-2017 demonstrated that the proposed hydropower dam operation rule could improve the water supply stability under severe drought conditions compared to the conventional operations. In the future, the role of hydropower dams for water resources management is expected to become more important, and this study can be widely used for water supply planning such as drought response using hydropower dams.

• Journal of Korea Water Resources Association
• /
• v.55 no.12
• /
• pp.1137-1147
• /
• 2022

River and groundwater stages are the main elements in the hydrologic cycle. They are spatially correlated and can be used to evaluate hydrological and agricultural drought. Stochastic simulation is often performed independently on hydrological variables that are spatiotemporally correlated. In this setting, interdependency across mutual variables may not be maintained. This study proposes the Bayesian vector autoregression model (VAR) to capture the interdependency between multiple variables over time. VAR models systematically consider the lagged stages of each variable and the lagged values of the other variables. Further, an autoregressive model (AR) was built and compared with the VAR model. It was confirmed that the VAR model was more effective in reproducing observed interdependency (or cross-correlation) between river and ground stages, while the AR generally underestimated that of the observed.

• Geophysics and Geophysical Exploration
• /
• v.25 no.3
• /
• pp.120-128
• /
• 2022

There are 17,000 reservoir dams in Korea, of which more than 85% were built over 50 years ago. Old embankment dams are weakened by internal erosion and suffusion phenomena due to preferential leakage paths and this ongoing weakening can cause their failure. Therefore, early warning associated with leakage in an embankment dam is crucial to prevent its failure. An electrical resistivity survey is a non-destructive, real-time and in-situ technique for detecting the development of leakage zones and general conditions of embankment dams. Because of its advantages, the electrical resistivity survey is widely used for reservoir safety inspections. However, the electrical resistivity survey is still not officially included in the precise safety inspection of reservoir dams because it cannot present a quantitative index of dam safety. In this study, we propose a method for calculating the leak index according to the water content evaluated from the electrical resistivity survey and/or induced polarization survey. Particularly, by proposing a quantitative leak index calculation method from monitoring surveys and independent surveys, we provide a theoretical basis for including electrical resistivity and induced polarization surveys as components of the precise safety inspection of reservoirs dams.

• Geophysics and Geophysical Exploration
• /
• v.26 no.4
• /
• pp.211-228
• /
• 2023

Ground-penetrating radar (GPR) surveys are commonly used to monitor embankments, which is a nondestructive geophysical method. The results of GPR surveys can be complex, depending on the situation, and data processing and interpretation are subject to expert experiences, potentially resulting in false detection. Additionally, this process is time-intensive. Consequently, various studies have been undertaken to detect cavities in GPR survey data using deep learning methods. Deep-learning-based approaches require abundant data for training, but GPR field survey data are often scarce due to cost and other factors constaining field studies. Therefore, in this study, a deep- learning-based model was developed for embankment GPR survey cavity detection using data augmentation strategies. A dataset was constructed by collecting survey data over several years from the same embankment. A you look only once (YOLO) model, commonly used in computer vision for object detection, was employed for this purpose. By comparing and analyzing various strategies, the optimal data augmentation approach was determined. After initial model development, a stepwise process was employed, including box clustering, transfer learning, self-ensemble, and model ensemble techniques, to enhance the final model performance. The model performance was evaluated, with the results demonstrating its effectiveness in detecting cavities in embankment GPR survey data.

• Korean Journal of Community Nutrition
• /
• v.25 no.2
• /
• pp.91-101
• /
• 2020

Objectives: The aim of this study was to investigate dietary intakes and nutritional status among Uganda primary school children from two selected schools in urban and rural areas. Methods: Data were collected from 350 pupils (6-14 years) in Mpigi district, Uganda. All participants were offered a school lunch meal (usually maize porridge and boiled beans). Dietary survey was conducted in October 2016. Data for dietary intake levels were collected by the 24-hour recall method with trained school staffs. The data were converted into nutrient intakes using the CAN-Pro 5.0 Program and compared with KDRIs to evaluate the nutritional status of the subjects. Diet quality indexes such as nutrient density, nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and index of nutritional quality (INQ) and a diet diversity index such as diet diversity score (DDS) were calculated to evaluate nutritional status among subjects. Data were analyzed using SPSS statistical programs. Results: Results show that the intakes of most nutrients were significantly different by schools. The nutritional status of micro-nutrients was very low in both schools according to analysis of nutritional indexes such as NARs and INQs. Students from both schools should improve intakes of micro-nutrients related to child growth such as calcium, Vitamin B₆, zinc and folate. According to the analysis of dietary diversity, there was difference in dietary patterns by schools presumably due to their locations. Conclusions: This suggests that current meals could not provide adequate nutrients for the subjects and urgent nutrition interventions for school food services are needed to improve their nutritional well-being. New foods supplements based on local cuisine are also needed to ensure dietary diversity and sustainable development plans.

• The Journal of Engineering Geology
• /
• v.26 no.4
• /
• pp.515-529
• /
• 2016

In this study, geochemical composition, CFCs (Chlorofluorocarbons), ${\delta}^{18}O$, ${\delta}D$, ${\delta}^{13}C$ isotopes and noble gases isotopes (He, Ne) were analyzed to determine their recharge age, source of $CO_2$ gas and noble gases of carbonated hot spring water and carbonated-water samples collected in the Seoqwipo of the Jeju. The pH of the carbonated waters ranges from 6.21 to 6.84, and the high electrical conductivity range ($1,928{\sim}4,720{\mu}S/cm$). Their chemical composition is classified as $Mg(Ca,\;Na)-HCO_3$ and $Na(Ca,\;Mg)-HCO_3$ types. As a result of the calculation of groundwater age using CFCs concentrations as an environmental tracer, the carbonated water and groundwater were estimated to be about 47.5~57.2 years and about 30.3~49.5 years, respectively. The ${\delta}^{13}C$ values of carbonated water range from -1.77 to -7.27‰, and are plotted on thr deep-seated field or the mixing field of the deep-seated and inorganic origin. Noble gases isotopic ($^3He/^4He$, $^4He/^{20}Ne$) ratio shows that helium gas of carbonated hot waters comes from deep-seated magma origin.

• Journal of agricultural medicine and community health
• /
• v.37 no.3
• /
• pp.167-180
• /
• 2012

Objective: This study was conducted to evaluate an education program for cardiocerebrovascular high-risk patients. Methods: This program was developed according to Tyler's model for curriculum development. To evaluate the effects of this program, we measured clinical outcome change (weight, waist circumference, systolic blood pressure, diastolic blood pressure) and behavior change stages (checking blood pressure, blood sugar levels, doing physical activity, consistent maintenance of food intake, eating low amounts of salt, abstention from tobacco and alcohol) before and 4 weeks after participation in the education program. The group of subjects consisted of High-risk group patients who attended basic program(32 patients), and staged program(37 patients) during KHyDDI meetings from Oct. 2009 to May 2010. Results: The staged educational program was developed three aspects(disease, nutrition and exercise)and three stages(basic, in-depth and individual education). In the staged education program, the evaluations were made by measuring clinical outcome and stage of behavior before and after education. Significant differences were found in waist circumference, systolic blood pressure, diastolic blood pressure, consistent maintenance of food intake(p<0.05), and eating low salt(p<0.001)and their self efficacy. Conclusion: In the practice-oriented staged education program, significant differences were found in the clinical outcomes and stage of behavior before and after education. Possible limitations of the study include the small number of participating subjects and the short follow-up management period, but the results indicate that continued application of this program could contribute to the prevention of cardiocerebrovascular diseases for the elderly patients with long periods of chronic diseases.