• Journal of environmental and Sanitary engineering
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• v.16 no.4
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• pp.21-30
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• 2001

Vehicles, especially diesel-using, are a major source of airborne particulate matter(PM), nitrogen dioxide($NO_2$) and so on in metropolitan cities such as Seoul. Therefore workers, who are mainly merchants, near roadside may be highly exposed to air pollutants from exhausted emissions of vehicles. This means that occupational type and location can affect the workers＇health by exposure to outdoor pollutions of ambient as well as indoor pollutions of working condition, respectively. In this study, we simultaneously measured the PM3.5 and $NO_2$concentrations in indoor and outdoor of shoes repair shops in Seoul, which were generally located at roadside in Korea. Shoes repairmen were highly exposed to PM3.5 and $NO_2$ both indoor and outdoor of repair shops comparing with other sub-population groups. High exposure to air pollutants for shoes repairmen was considered to be outdoor source from exhausted emission of vehicles and indoor source from working condition. The $PM3.5/NO_2$ concentration ratio was $1.17{\pm}$0.59 in roadside, of which ratio was higher 7han ratios of other studies. This result suggested that major air pollutant in Seoul was fine particle. Also, this PM3.5 to $NO_2$ ratio will be used in environmental exposure and risk assessment by estimation of PM3.5 concentration as measuring the only $NO_2$ concentration with small and accurate $NO_2$ passive sampler.

• Journal of Environmental Health Sciences
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• v.43 no.4
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• pp.298-306
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• 2017

Objectives: Since 1998, the Korea National Health and Nutrition Examination Survey (KNHANES) has been conducted in order to investigate the health and nutritional status of Koreans. The food intake data of individuals in the KNHANES has also been utilized as source dataset for risk assessment of chemicals via food. To improve the reliability of intake estimation and prevent missing data for less-responded foods, the structure of integrated long-standing datasets is significant. However, it is difficult to merge multi-year survey datasets due to ineffective cleaning processes for handling extensive numbers of codes for each food item along with changes in dietary habits over time. Therefore, this study aims at 1) cleaning the process of abnormal data 2) generation of integrated long-standing raw data, and 3) contributing to the production of consistent dietary exposure factors. Methods: Codebooks, the guideline book, and raw intake data from KNHANES V and VI were used for analysis. The violation of the primary key constraint and the $1^{st}-3rd$ normal form in relational database theory were tested for the codebook and the structure of the raw data, respectively. Afterwards, the cleaning process was executed for the raw data by using these integrated codes. Results: Duplication of key records and abnormality in table structures were observed. However, after adjusting according to the suggested method above, the codes were corrected and integrated codes were newly created. Finally, we were able to clean the raw data provided by respondents to the KNHANES survey. Conclusion: The results of this study will contribute to the integration of the multi-year datasets and help improve the data production system by clarifying, testing, and verifying the primary key, integrity of the code, and primitive data structure according to the database normalization theory in the national health data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.3
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• pp.299-309
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• 2006

In recent years, a large natural disasters have occurred due to worldwide abnormal weather and the amount of damage has been increased more resulting from high density population and a large-sized buildings of the urbanized area. In this study. we estimate the flooded area according to rainfall probability intensify and sea level in Woreong dong, Masan occurred flood damages by typhoon Maemi using SWMM, a dynamic rainfall-runoff simulation model in urban area, and then analyze the damage of flood expected area through connecting with GIS database. In result, we can predict accurately expected area of inundation according to the rainfall intensity and sea level rise through dividing the study area into sub-area and estimating a flooded area and height using SWMM. We provide also the shelter information available for urban planning and flood risk estimation by landuse in expected flood area. Further research for hazard management system construction linked with web or wireless communication technology expects to increase its application.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1729-1733
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• 2009

유역에서의 수자원관리에 큰 과제로 대두되고 있는 댐의 탁수문제에 대한 종합적인 대책 마련을 위해서 국내 댐 유역의 탁수발생의 가능성과 탁수 발생시 피해 가능성에 대한 체계적인 검토가 이루어져야 한다. 본 연구에서는 댐의 탁수문제에 대한 종합적인 대책을 마련하기 위해 댐 유역의 탁수 위험도를 평가할 수 있는 방법을 개발하였다. 종합적인 탁수 위험성을 평가하기 위해서 탁수 평가지표를 개발하였고, 이를 통해서 5개 댐 유역에 대한 시범평가를 실시하였다. 탁수 위험도 평가를 위해서 평가 분야를 탁수 취약성과 탁수 피해성, 탁수 영향의 3가지 분야로 구분하여 계층화된 형태로 종합지표화하였고, AHP기법을 적용하여 평가분야와 세부평가지표에 대한 가중치를 결정하였다. 시범평가 결과 5개댐 중 실제 탁수발생 현상은 일부 댐에서만 높게 나타나고 있으나, 대부분의 댐들이 탁수발생 잠재성이 높은 것으로 확인되었다. 평가 대상 댐 중에서는 임하댐과 소양댐 순으로 종합적인 탁수위험도가 높은 것으로 나타났다. 탁수 평가 지표를 개발하기 위하여, 기존의 국내외의 조사결과 등을 토대로 90여개의 탁수관련 인자들을 탁수발생 잠재성, 과거 탁수 발생 여부, 탁수 영향 등의 3가지 분야로 분류하여 최종적으로 7가지의 세부평가항목(강우지표, 유역지질, 토사유출량, 최고탁도, 고탁도 지속기간, 용수이용량, 호소생태기능)을 결정하였다. 7가지의 지표들은 탁수와의 상관성을 고려하여 표준화시켰고, 세부 평가항목들의 가중합이 종합적인 평가지표가 되도록 하였다. 댐의 탁수 위험성에 대한 평가는 댐유역의 종합적인 탁수 위험도 평가와 분야별 평가, 댐별 세부항목 평가로 구분하여 이루어졌다. 시범평가는 국내의 주요 5개 수계별로 1개의 댐을 선정하여 이루어졌다. 추가적으로 AHP의 적용시 생길 수 있는 지표의 중복성과 상호연계성, 평가자의 편향 등으로 인한 문제들을 어떻게 해결하여야 하는지에 대해서도 검토하였다.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.17-24
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• 2010

A logistic model for describing combined effects of both temperature and wetness period on appressorium formation was developed using laboratory data on percent appressorium formation of Colletotrichum acutatum. In addition, the possible use of the logistic model for forecasting infection risks was also evaluated as compared with a first-order linear model. A simplified equilibrium model for enzymatic reactions was applied to obtain a temperature function for asymptote parameter (A) of logistic model. For the position (B) and the rate (k) parameters, a reciprocal model was used to calculate the respective temperature functions. The nonlinear logistic model described successfully the response of appressorium formation to the combined effects of temperature and wetness period. Especially the temperature function for asymptote parameter A reflected the response of upper limit of appressorium formation to temperature, which showed the typical temperature response of enzymatic reactions in the cells. By having both temperature and wetness period as independent variables, the nonlinear logistic model can be used to determine the length of wetness periods required for certain levels of appressorium formation under different temperature conditions. The infection model derived from the nonlinear logistic model can be used to calculate infection risks using hourly temperature and wetness period data monitored by automated weather stations in the fields. Compared with the nonlinear infection model, the linear infection model always predicted a shorter wetness period for appressorium formation, and resulted in significantly under- and over-estimation of response at low and high temperatures, respectively.

• Survey Research
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• v.10 no.2
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• pp.97-114
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• 2009

Even the importance and necessity of a basic national statistical survey, the population and housing census is facing with some practical difficulties such as higher survey cost, decrease of survey information and much longer survey period. As an alternative to the traditional census for tackling such difficulties, a rolling census has been introduced. The rolling census has some advantages such as improved timeliness with much more frequent data and evenly distributed survey cost over several years. On the contrary, the rolling census has also some disadvantages such as the lost of snapshot feature of the population and increasing risk of outside influence on field work. In this paper we reviewed the French rolling census and the American community survey as roiling surveys, and then investigated some factors like balanced sample selection, population update, synthetic estimation, and the operation of rolling survey, which are to be checked carefully in case of introducing a rolling census as an alternative to the current census.

• Korean Journal of Community Nutrition
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• v.25 no.2
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• pp.150-158
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• 2020

Objectives: This study was conducted to estimate usual meat intake distribution, which may have been over/underestimated when estimations were made using only the third food codes of the Korea National Health and Nutrition Examination Survey (KNHANES). Methods: For this purpose, 24-hour recall data from the 2009 Korea National Health and Nutrition Examination Survey, which conducted a partial 2-day survey of food intake, were used. The Multiple Source Method (MSM) was used to estimate the distribution of the usual intake of red and processed meats. Results: The results of this study show that the mean intake of red meat was 45.07 g while that of processed meat was 4.33 g. These results are slightly higher than the consumption calculated using only tertiary food code, and the difference was statistically significant. Furthermore, characteristics of the estimated usual intake distribution were a smaller standard deviation, increased lower percentiles, and decreased upper percentiles compared to the 2-day mean intake distribution for both red and processed meats. The proportion of individuals not consuming red meat decreased substantially from approximately 37% to 0.7%. The proportion of consumption that exceeded 90 g, which is the upper limit of red meat intake recommended by the National Health Service (NHS), was only approximately 10% in the distribution of usual intake. Conclusions: As the consumption of processed foods is expected to continuously increase, caution is needed regarding the processes used to calculate food (group) intake to avoid over/underestimation. Moreover, use of KNHANES data to calculate the proportion of the population at risk of insufficiency or excess intake of certain nutrients or food (group), based on one day intake that does not address within-individual variation, may lead to biased estimates.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.05a
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• pp.150-151
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• 2003

Benzoyl peroxide is a high production volume chemical, which was produced about 1,375 tons/year in Korea as of 2001 survey. Most of them are used as initiators in polymerization, catalysts in the plastics industry, bleaching agents for flour and medication for acne vulgaris. The substance is one of the sever chemicals of which human and environmental risks are being assessed by National Institute of Environmental Research under the frame of OECD SIDS Program. It has a melting point of 104-106 $^{\circ}C$ and has solubility of 9.1 mg/1 in water at 25 $^{\circ}C$. The substance was readily biodegradable (83 % after 21days) and had toxic effects to aquatic organisms. The range of 72 hr-EbC50 (biomass) for algae was 0.07-0.44 mg/1 and 48 hr-EC50 for daphnia was 0.07-2.91 mg/1. The LC50 of acute toxicity to fish was 0.24-2.0 mg/1. Although the toxic effects of benzoyl peroxide to aquatic organisms were investigated, environmental monitoring data were not studied. In this study, distribution of the chemical among multimedia environment was estimated using EQC model based on the physical-chemical properties to evaluate the risk of benzoyl peroxide in environment. In level I, II calculation the chemical was distributed to soil (68.3 %) and water (28.7 %). In level III calculation it was primarily distributed to soil (99.9 %) and overall residence time of 3.4 years was estimated. Benzoyl peroxide could be persistent in environment.

• Structural Engineering and Mechanics
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• v.74 no.6
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• pp.821-832
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• 2020

The fundamental period is an important parameter for seismic design and seismic risk assessment of building structures. In this paper, a simplified theoretical method to predict the fundamental period of masonry infilled reinforced concrete (RC) frame is developed based on the basic theory of engineering mechanics. The different configurations of the RC frame as well as masonry walls were taken into account in the developed method. The fundamental period of the infilled structure is calculated according to the integration of the lateral stiffness of the RC frame and masonry walls along the height. A correction coefficient is considered to control the error for the period estimation, and it is determined according to the multiple linear regression analysis. The corrected formula is verified by shaking table tests on two masonry infilled RC frame models, and the errors between the estimated and test period are 2.3% and 23.2%. Finally, a probability-based method is proposed for the corrected formula, and it allows the structural engineers to select an appropriate fundamental period with a certain safety redundancy. The proposed method can be quickly and flexibly used for prediction, and it can be hand-calculated and easily understood. Thus it would be a good choice in determining the fundamental period of RC frames infilled with masonry wall structures in engineering practice instead of the existing methods.

• Anxiety and mood
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• v.13 no.2
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• pp.53-59
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• 2017

Reliable and valid diagnostic screening tools in the primary care setting enable accurate estimation of depression in individuals at risk or in need of treatment, and provide patients with an opportunity to receive optimal treatments. Although there have been extensive studies on screening tools for depression used in domestic mental health settings, there is little consideration and lack of a thorough review of the diagnostic validity of screening tools. In the current review, we selected 13 representative screening tools for depression which were evaluated in a total of 19 validation studies conducted in Korea. We summarized DSM-5 target domains, diagnostic indices, sensitivity, specificity, cut-off scores, and diagnostic validity information for each tool. Finally, the depression measurement expert group was constituted to evaluate the current status of screening tools for depression, and their recommendations for a new screening tool were summarized. This study was conducted as part of the Mental Health Technology Development project to develop the Korean screening tool for depression (K-DEP).