• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.801-806
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• 2015

The incidence of flood damage by global climate change has increased recently. Because of the increased frequency of flooding in Korea, the technology of flood prediction and prevalence has developed mainly for large river watersheds. On the other hand, there is a limit on predicting flooding through the most present flood forecasting systems because local floods in small watersheds rise quite quickly with little or no advance warning. Therefore, this study estimated the flood warning rainfall using a flood forecasting model at the two alarm trigger points in the Suamcheon basin, which is an urban basin with backwater effects. The flood warning rainfall was estimated to be 25.4mm/120min ~ 78.8mm/120min for the low water alarm, and 68.5mm/120min ~ 140.7mm/120min for the high water alarm. The frequency of the flood warning rainfall is 3-years for the low water alarm, and 80-years for the high water alarm. The results of this analysis are expected to provide a basic database in forecasting local floods in urban watersheds. Nevertheless, more tests and implementations using a large number of watersheds will be needed for a practical flood warning or alert system in the future.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.4
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• pp.220-228
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• 2017

Since the fine particulate matters occurred from mainly combustion in industry and road transport effect to human respiratory health, the interest and importance are getting increased. In 2013, the World Health Organization (WHO) concluded that outdoor air pollution is carcinogenic to humans, with the particulate matter component ($PM_{10}$ and $PM_{2.5}$) of air pollution most closely associated with increased cancer incidence, especially cancer of the lung. Therefore, many researches have been studied in the quantification and data development of fine particulate matters. Currently, the Ministry of Environment and cities/regions are developing the fine particulate matter data and air emission information. Particularly just $PM_{10}$ and $PM_{2.5}$ data is used in the fine particulate matters warning and alert. The data of NOx, SOx, $NH_3$, which have the particulate matter formation potential are not well considered. Also, the researches related with particulate matter formation potential and respiratory effects by industrial sectors and cities/regions are not conducted well. Therefore, the purpose of this study is to evaluate and calculate particulate matter formation potential and respiratory effects in 11 industrial sectors and cities using NOx, SOx, $PM_{10}$, $NH_3$ data (developed by Ministry of Environment and National Institute of Environmental Research) in 2001 and 2013. The results of this study will be provided the particulate matter formation potential and respiratory effects and will be used for future the fine particulate matter researches.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3101-3103
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• 2016

Background: According to the most recent estimation of GLOBOCAN, Cambodia has the highest incidence and mortality rate of cervical cancer in Southeast Asia. A screen-and-treat strategy using visual inspection with acetic acid (VIA test) and cryotherapy has been implemented in Cambodia's national cervical cancer screening program since 2013. However, where resources are available, cervical cytology with or without high-risk HPV DNA testing is the preferred screening method used in this country. Aim: This study aims to calculate the prevalence of abnormal cervical cytology and explain the possible factors contributing to a reduced quality of cervical cytology among women participating in a hospital-based cervical cancer screening program in Cambodia. Materials and Methods: A descriptive study was conducted using information from the cytology and pathology database in the Department of Pathology of Calmette Hospital between January 2012 and December 2015. Prevalence of abnormal cervical cytology, based on the Bethesda 2001 classification, was calculated. Data on the adequacy of cytological specimens were analyzed in order to explain the factors contributing to a reduced quality of cervical cytology interpretation. Results: Among 6,207 women who participated in the cervical cancer screening program at Calmette Hospital during 2012 and 2015, 388 (6.25%) had abnormal cytology, which could be classified into Atypical Squamous Cells of Undetermined Significance (92 cases; 1.48%), Atypical Squamous Cells - Cannot Exclude High-Grade Intraepithelial Lesion (13 cases; 0.21%), Atypical Glandular Cells (11 cases; 0.18%), Low-Grade Squamous Intraepithelial Lesion (221 cases; 3.56%), High-Grade Squamous Intraepithelial Lesion (26 cases; 0.42%), and Squamous Cell Carcinoma (25 cases; 0.40%). Unsatisfactory smears made up 12.2% of the total cases. The most frequently identified factor leading to unsatisfactory smears was the absence of cells from the transformation zone. Conclusions: The present study showed an overall prevalence of abnormal cervical cytology of 6.25%, which is comparable to that in many large population-based studies in the Asia Pacific region. Nevertheless, the remarkably high rate of unsatisfactory smears in this study justifies further improvement in specimen sampling among Cambodian gynecologists.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.717-722
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• 2013

Background: Breast cancer is the most common cancer among women worldwide. The aim of this study was to investigate the relationship between tumor size and axillary lymph node involvement (ALNI) in patients with invasive lesions, to find the best candidates for a full axillary dissection. Additionally, we evaluated the association between tumor size and invasive behavior. The study was based on data from 789 patients with histopathologically proven invasive breast cancer diagnosed in Shohada University hospital in Tehran, Iran (1993-2009). Cinical and histopathological characteristics of tumors were collected. Patients were divided into 6 groups according to primary tumor size: group I ($0.1-{\leq}1cm$), II ($1.1-{\leq}2cm$), III ($2.1-{\leq}3cm$), IV ($3.1-{\leq}4cm$), V ($4.1-{\leq}5cm$) and VI (>5cm). The mean(${\pm}SD$) size of primary tumor at the time of diagnosis was $3.59{\pm}2.69$ cm that gradually declined during the course of study. There was a significant correlation between tumor size and ALNI (p<0.001). A significant positive correlation between primary tumor size and involvement of surrounding tissue was also found (p<0.001). The mean number of LNI in group VI was significantly higher than other groups (p<0.05). We observed more involvement of lymph nodes, blood vessels, skin and areola-nipple tissue with increase in tumor size. We found 15.3% overall incidence of ALNI in tumors ${\leq}2cm$, indicating the need for more investigation to omit full axillary lymph node dissection with an acceptable risk for tumors below this diameter. While in patients with tumors ${\geq}2cm$, 84.3% of them had nodal metastases, so the best management for this group would be a full ALND. Tumor size is a significant predictor of ALNM and involvement of surrounding tissue, so that an exact estimation of the size of primary tumor is necessary prior to surgery to make the best decision for management of patients with invasive breast cancer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.11
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• pp.1077-1083
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• 2012

The jamming countermeasures in GNSS includes anti-jamming technique and jammer localization technique. In both techniques, direction of jamming signal is important and generally the MUSIC algorithm is used to find the direction of jamming signal. The MUSIC is super-resolution algorithm for detecting incident direction of signal. But, the search time of MUSIC algorithm is too long because all candidates of incidence angle are searched. This paper proposes the new method that has less computational burdens and therefore faster than the conventional MUSIC algorithm. The proposed method improves performance speed by reducing unnecessary calculations. In the proposed method, the cost function of conventional MUSIC algorithm is decomposed into the sum of squares and if the partial sum of cost function is larger than the minimum cost function so far, then the candidate is rejected and next candidates are searched. If the computed cost function is less than the minimum cost function so far, the minimum cost function so far is replaced with newly computed value. The performance of the proposed method was compared with the conventional MUSIC algorithm using the simulation. The accuracy of the estimaed direction of jamming signal was same as the conventional MUSIC while the search speed of the proposed method was 1.15 times faster than the conventional MUSIC.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.168-178
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• 2022

In this study, the resistance test, the vertical static angle of the attack test and VPMM test will be conducted to estimate the maneuverability of underwater vehicles with ahead propeller. The vertical static test will be conducted within the range of -40deg to 40deg, to investigate the cross-flow drag at high incidence angles. The tests will be conducted by dividing the propeller rotation into a case in which the propeller rotates at a specific rpm, and a case in which the propeller rotates naturally, according to the towing speed. Hydrodynamic coefficients of vertical direction will be estimated by the captive model tests. Additionally, the vertical dynamic stability index based on estimated hydrodynamic coefficients will be calculated and the impact of the propeller revolution state on the index will be investigated. The results are expected to be used as reference test data for underwater vehicles with ahead propeller.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.782-793
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• 2022

The rise in chronic disease not only has a negative effect on people's lives, but it also increases the cost of medical care owing to the increased usage of medical care as health and medical technology improves, life expectancy rises, and rapid population ageing. In such context, this study examined the difference in the disease cost of hypertension according to demographic information and the effect of the initial diagnosis age and treatment period on the cost. This study used the Korean Health Panel Survey from 2010 to 2017, and selected subjects based on health insurance beneficiaries between the ages of 30 and under 80. With the selected data, the direct and indirect costs of disease loss were calculated according to the cost of illness approach, and we constructed a disease-loss ratio cohort considering the age of diagnosis and time of treatment for hypertension. From the results of the study, the annual cost of disease loss for hypertensive patients differed by gender by 110,107 won, and it was found that the cost increased by 1.8 times as the treatment time increased. In addition, when comparing disease loss ratios between the same age groups, it was found that the disease loss ratios between those in their 60s and 70s were affected by treatment time. This study confirmed that hypertension significantly affects the cost of the disease, and not only requires early diagnosis and management, but also preventive efforts to lower the incidence of hypertensive disease must be strengthened.

• Korean Journal of Radiology
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• v.21 no.11
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• pp.1230-1238
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• 2020

Objective: We aimed to assess the effects of remote ischemic pre-conditioning (RIPC) on the incidence of contrast-induced nephropathy (CIN) after an intravenous (IV) or intra-arterial injection of contrast medium (CM) in patient and control groups. Materials and Methods: This prospective, randomized, single-blinded, controlled trial included 26 patients who were hospitalized for the evaluation of the feasibility of transcatheter aortic valve implantation and underwent investigations including contrast-enhanced computed tomography (CT), with Mehran risk scores greater than or equal to six. All the patients underwent four cycles of five minute-blood pressure cuff inflation followed by five minutes of total deflation. In the RIPC group (n = 13), the cuff was inflated to 50 mm Hg above the patient's systolic blood pressure (SBP); in the control group (n = 13), it was inflated to 10 mm Hg below the patient's SBP. The primary endpoint was the occurrence of CIN. Additionally, variation in the serum levels of cystatin C was assessed. Results: One case of CIN was observed in the control group, whereas no cases were detected in the RIPC group (p = 0.48, analysis of 25 patients). Mean creatinine values at the baseline, 24 hours after injection of CM, and 48 hours after injection of CM were 88 ± 32 μmol/L, 91 ± 28 μmol/L and 82 ± 29 μmol/L, respectively (p = 0.73) in the RIPC group, whereas in the control group, they were 100 ± 36 μmol/L, 110 ± 36 μmol/L, and 105 ± 34 μmol/L, respectively (p = 0.78). Cystatin C values (median [Q1, Q3]) at the baseline, 24 hours after injection of CM, and 48 hours after injection of CM were 1.10 [1.08, 1.18] mg/L, 1.17 [0.97, 1.35] mg/L, and 1.12 [0.99, 1.24] mg/L, respectively (p = 0.88) in the RIPC group, whereas they were 1.11 [0.97, 1.28] mg/L, 1.13 [1.08, 1.25] mg/L, and 1.16 [1.03, 1.31] mg/L, respectively (p = 0.93), in the control group. Conclusion: The risk of CIN after an IV injection of CM is very low in patients with Mehran risk score greater than or equal to six and even in the patients who are unable to receive preventive hyperhydration. Hence, the Mehran risk score may not be an appropriate method for the estimation of the risk of CIN after IV CM injection.

• Journal of Preventive Medicine and Public Health
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• v.32 no.3
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• pp.333-342
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• 1999

Objectives: Most descriptive studies of cancer have focused either or cancer incidence or mortality. Cancer prevalence has rarely been estimated. Cancer prevalence data can be used as a measure of the economic and social burden of cancer and are also useful for health care planning. This study attempts to estimate cancer prevalence in Kangwha county. Methods: This investigation is based on data of Kangwha cancer registry. The data include all cases of cancer diagnosed from 1983 through 1992. We define 'prevalent cases' as cancer patients who is alive as of January 1, 1993. For each five-year age group, the number of 'known prevalent cases' is added to the number of 'estimated prevalent cases'. Prevalence is calculated by dividing these sums by the populations of Kangwha County on December 31, 1992(derived from Kangwha Statistics Annual). Results: Crude prevalence of cancel among males and females are 536.7 and 601.1 per 100,000 respectively. Gastric cancer is the most common malignant neoplasm(213.2 per 100,000, crude prevalence) among males. It is followed by lung cancer(45.1 per 100,000), liver cancer(32.8 per 100,000), rectal cancer(25.4 per 100,000) and colon cancer(25.4 per 100,000). Cervical cancer is the most common cancer(201.9 per 100,000, crude prevalence) and is fellowed by gastric cancer(91.5 per 100,000), thyroid cancer(64.8 per 100,000), breast cancer(57.2 per 100,000) and rectal cancer(32.7 per 100,000) among females. Conclusions: We tried to estimate cancer prevalence based on the Kangwha cancer registry for the first time in Korea. The estimation of cancer prevalence based on a population-based cancer registry will be more correct and useful as the data accumulate. We will make another estimation in the near future.

• Journal of Global Scholars of Marketing Science
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• v.19 no.2
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• pp.17-26
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• 2009

As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.