• Journal of Wetlands Research
• /
• v.21 no.3
• /
• pp.191-198
• /
• 2019

High impervious surfaces increase the surface runoff during rainfall and reduces the underground infiltration thereby leading to water cycle distortion. The distortion of water cycle causes various urban environmental problems such as urban flooding, drought, water pollutant due to non-point pollution runoff, and water ecosystem damage. Climate change intensified seasonal biases in urban rainfall and affected urban microclimate, thereby increasing the intensity and frequency of urban floods and droughts. Low impact development(LID) technology has been applied to various purposes as a technique to reduce urban environmental problems caused by water by restoring the natural water cycle in the city. This study evaluated the contribution of hydrologic characteristics and water cycle recovery after LID application using long-term monitoring results of various LID technology applied in urban areas. Based on the results, the high retention and infiltration rate of the LID facility was found to contribute significantly to peak flow reduction and runoff delay during rainfall. The average runoff reduction effect was more than 60% at the LID facility. The surface area of the LID facility area ratio(SA/CA) was evaluated as an important factor affecting peak flow reduction and runoff delay effect.

• Journal of Korean Society of Disaster and Security
• /
• v.12 no.2
• /
• pp.15-24
• /
• 2019

In the previous study, the rainfall data of 1 hour, 6 hours and 3 days were used as the rainfall criterion according to the grade to trigger the debris flow in the highway area, using the rainfall data of Gangwon area and the rainfall time-series data at the spot where the debris flow occurred. In this study, we propose an early warning criterion of the highway debris flow triggering through appropriate combination of three rainfall criteria selected through previous studies and adjustments of rainfall criterion in the highway debris flow triggering. In addition, simulations were conducted using the time-series rainfall data of 2010~2012, which had a large amount of precipitation for the five sites where debris flows occurred in 2013. As a result of the study, the criteria for the early warning of highway unsteadiness on the highway were prepared. In case of the grade-based adjustment, it is preferable to apply the unified rating to the grade B. Also, if the fatigue of the monitoring is not a problem, adjusting it to A or S may be a way to positively cope with the occurrence of highway debris flow.

• Applied Chemistry for Engineering
• /
• v.30 no.1
• /
• pp.81-87
• /
• 2019

In this study, synthetic methods and physical properties for a new class of glycidyl azide polymer (GAP) were investigated for energetic thermoplastic elastomers (ETPE). Four kinds of GAP copolymer polyols were synthesized by introducing nucleophiles such as azide, alkoxide and alkyl amine into poly(epichlorohydrin) (PECH). The GAP copolymer synthetic reaction can be evaluated as an environmental benign and efficient synthetic method due to the simultaneous one-step reaction using two kinds of nucleophiles and the complete consumption of sodium azide. The relative stoichiometric substitution ratio analysis and the progress of reaction were checked and monitored by inverse gated decoupled $^{13}C$ NMR and Fourier transform infrared (FT-IR) spectroscopy. The glass transition temperature and molecular weight were measured by differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) analysis. The synthesized poly($GA_{0.8}-butoxide_{0.2}$), poly($GA_{0.7}-n-butylamine_{0.3}$), poly($GA_{0.7}-dipropylamine_{0.3}$) and poly($GA_{0.7}-morpholine_{0.3}$) had a glass transition temperature ranged from -39 to $-26^{\circ}C$.

• The Journal of the Korea Contents Association
• /
• v.18 no.12
• /
• pp.208-217
• /
• 2018

The purpose of this study was to provide information on the treatment and management of diabetic patients using all the available data of the Korea National Health and Nutrition Examination Survey (KNHANES, 2013-2015) on the serological and complication patterns of cardiovascular disease (CVD) according to the duration of diabetes mellitus (DM). KNHANES consists of health questionnaires, screenings, and nutrition surveys. The study subjects were 1,316 persons who were aged between 18 and 80 years and who answered the duration of DM. DM was classified as 0-5, 6-10, 11-15, 16-20, and over 20 years according to duration of DM. The longer the duration of DM, the older the BMI, the lower the smoker, the higher the HbA1c and the lower the glomerular filtration rate. Total cholesterol, LDL-C and triglyceride levels were low and HDL-C levels were similar. The proportion of patients receiving insulin and oral hypoglycemic agents increased. The longer the duration of DM, the worse blood glucose control and the increased risk of microvascular and macrovascular complications. To prevent these complications, intensive care and monitoring should be used to control the risk factors.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.37 no.3
• /
• pp.167-175
• /
• 2019

Water color analysis allows non-destructive estimation of abundance of optically active water constituents in the water body. Recently, there have been increasing needs for light-weighted multispectral cameras that can be integrated with low altitude unmanned platforms such as drones, autonomous vehicles, and heli-kites, for the water color analysis by spectroradiometers. This study performs the preprocessing of the Micasense Rededge-M camera which recently receives a growing attention from the earth observation community for its handiness and applicability for local environment monitoring, and investigates the applicability of Rededge-M data for water color analysis. The Vignette correction and the band alignment were conducted for the radiometric image data from Rededge-M, and the sky, water, and solar radiation essential for the water color analysis, and the resultant remote sensing reflectance were validated with an independent hyperspectral instrument, TriOS RAMSES. The experiment shows that Rededge-M generally satisfies the basic performance criteria for water color analysis, although noticeable differences are observed in the blue (475 nm) and the near-infrared (840 nm) band compared with RAMSES.

• Korean Journal of Remote Sensing
• /
• v.34 no.6_1
• /
• pp.997-1007
• /
• 2018

Drought monitoring is the important system for disasters by climate change. To perform this, it is necessary to measure the precipitation based on satellite rainfall estimation. The data developed in this study provides two kinds of satellite data (raw satellite data and bias-corrected satellite data). The spatial resolution of satellite data is 10 km and the temporal resolution is 1 day. South Korea was selected as the target area, and the original satellite data was constructed, and the bias-correction method was validated. The raw satellite data was constructed using TRMM TMPA and GPM IMERG products. The GRA-IDW was selected for bias-correction method. The correlation coefficient of 0.775 between 1998 and 2017 is relatively high, and TRMM TMPA and GPM IMERG 10 km daily rainfall correlation coefficients are 0.776 and 0.753, respectively. The BIAS values were found to overestimate the raw satellite data over observed data. By using the technique developed in this study, it is possible to provide reliable drought monitoring to Korean peninsula watershed. It is also a basic data for overseas projects including the un-gaged regions. It is expected that reliable gridded data for end users of drought management.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.39 no.4
• /
• pp.505-512
• /
• 2019

This study is a basic study to prepare safety measures for the tram that is being introduced into Korea by reviewing accident analysis and accident compensation system of the tram. Analysis of accident characteristics of the tram was analyzed based on overseas data. Five years after the inauguration of the tram, accidents were halved and stabilized. Deaths accounted for 0.5 % of all casualties, most accidents were minor. Accidents with other mean transportation were high 84.1 %, among them accidents with passenger cars was found to be highest. The frequent points of accidents were analyzed as intersections and tram stop, and measures for pedestrian accidents were found to be important. Those are proposed safety measures through analyzing tram accident characteristics: Monitoring accidents which occur within five years of its inauguration, developing accident database input system, installation of fences for preventing people from jaywalking, operating traffic signal for preventing people from jaywalking through connection of pedestrian signals and tram signals, clamping down on illegal U-turn cars and jaywalking pedestrian, Also, those are proposed accident treatment measures based on general driver receptively and overseas data: property damage liability coverage (PI) of car insurance, comparative negligence when the accident occurs between car and tram.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.4
• /
• pp.93-103
• /
• 2021

Despite the efforts of financial authorities in conducting the direct management and supervision of collection agents and bond-collecting guideline, the illegal and unfair collection of debts still exist. To effectively prevent such illegal and unfair debt collection activities, we need a method for strengthening the monitoring of illegal collection activities even with little manpower using technologies such as unstructured data machine learning. In this study, we propose a classification model for illegal debt collection that combine machine learning such as Support Vector Machine (SVM) with a rule-based technique that obtains the collection transcript of loan companies and converts them into text data to identify illegal activities. Moreover, the study also compares how accurate identification was made in accordance with the machine learning algorithm. The study shows that a case of using the combination of the rule-based illegal rules and machine learning for classification has higher accuracy than the classification model of the previous study that applied only machine learning. This study is the first attempt to classify illegalities by combining rule-based illegal detection rules with machine learning. If further research will be conducted to improve the model's completeness, it will greatly contribute in preventing consumer damage from illegal debt collection activities.

• Korean Journal of Food Science and Technology
• /
• v.52 no.6
• /
• pp.661-669
• /
• 2020

Samgak-Kimbap is a popular ready-to-eat (RTE) food at convenience stores, in Korea. Although Samgak-Kimbap is distributed through the cold chain supply system, inappropriate temperature storage conditions prior to consumption are a cause of concern. The objective of this study was to evaluate the risk of Staphylococcus aureus growth in Samgak-Kimbap in the retail market. The prevalence and contamination levels of S. aureus in Samgak-Kimbap (n=170) were monitored, and the predictive growth model of a five-strain cocktail of enterotoxin-producing S. aureus (SEA, SEB, SEC, SED, and SEE) was developed in Samgak-Kimbap as a function of temperature (4, 10, 11, 20, 25, and 37℃). We could not observe the growth of S. aureus and enterotoxin-producing S. aureus in Samgak-Kimbap at temperatures below 10℃. The probability of illness with S. aureus per serving of Samgak-Kimbap was 1.44×10-10 per day. The most influential factor in increasing the risk of foodborne illnesses was the contamination level of S. aureus in Samgak-Kimbap.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.8
• /
• pp.83-90
• /
• 2021

In this paper, effects on industrial accident prevention based on better safety and health environment by utilizing ergonomics expert were studied. This study was mainly based on the data from 'the survey for occupational safety and health trend' conducted by Occupational Safety and Health Research Institute. The number of industries participated in the survey was 2,084. Main results of the study were as follows; 1) Only 22.9% of the industries participated in the survey utilized ergonomics expert. The rest of the industries have never had an ergonomics expert due to the reasons such as lack of knowledge for the field of ergonomics, etc. 2) Specific activities done by the industries with ergonomics expert in order to have better safety & health were 'providing work orders'(94.8%), 'providing monitoring guidelines'(85.5%), 'providing information for dangerous work'(95.8%), 'providing safety education'(96.6%), and 'other safety management'(94.1%). 3) When the odds ratio for the levels of communication and the levels of environmental stability regarding safety & health for the different groups(with experts and without experts), it was found that the group with ergonomics experts had a significant higher ORs(2.391, 95% confidence interval(1.949-2.932) and 2.128, 95% confidence interval(1.786-2.537)) respectively than those of the industries without ergonomics expert. The results suggested that ergonomics expert has been unique in most of time in terms of his/her contributions in the field of industrial safety and health.