• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.413-419
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• 2010

A silica mine monitoring was conducted from March to December in 2008 to measure rainfall, runoff amounts and pollution loads. A total of 13 rainfall-runoff events were measured and analyzed with respect to runoff ratio, pollutant concentration and load, and initial flush. Over rainfall-runoff events, 95% confidence range of SS concentration was 942.5~2,056.2 mg/L. Other measured water quality indices also showed relatively large variation. This wide concentration variation was thought to be caused by the bare working ground of the mine that was used to store, process and transport the mined silica. Total pollution load of the 13 rainfall-runoff events was SS 17,901 kg/ha, $COD_{Cr}$ 160.9 kg/ha, $COD_{Mn}$ 111.24 kg/ha, BOD 79.6 kg/ha, T-N 13.8 kg/ha, T-P 3.5 kg/ha, and TOC 39.3 kg/ha. Initial flush was not well observed except SS. Very high SS concentration and load was occurred when rainfall was large. Therefore, it was recommended to manage the bare ground not to discharge excessive pollutants during wet days by covering the ground or constructing runoff treatment systems such as a sediment basin.

• Radiation Oncology Journal
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• v.37 no.2
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• pp.73-81
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• 2019

Purpose: There is sparse literature on treatment outcomes research on resectable oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to measure the treatment outcomes, explore the failure patterns, and identify the potential clinicopathological prognostic factors affecting treatment outcomes for resectable OTSCC. Materials and Methods: It is a retrospective analysis of 202 patients with resectable OTSCC who underwent upfront primary surgical resection followed by adjuvant radiotherapy with or without concurrent chemotherapy if indicated. Results: The median follow-up was 35.2 months (range, 1.2 to 99.9 months). The median duration of locoregional control (LRC) was 84.9 months (95% confidence interval, 67.3-102.4). The 3- and 5-year LRC rate was 68.5% and 58.3%, respectively. Multivariate analysis showed that increasing pT stage, increasing pN stage, and the presence of extracapsular extension (ECE) were significantly associated with poorer LRC. The median duration of overall survival (OS) was not reached at the time of analysis. The 3- and 5-year OS rate was 70.5% and 66.6%, respectively. Multivariate analysis showed that increasing pT stage and the presence of ECE were significantly associated with a poorer OS. Conclusion: Locoregional failure remains the main cause of treatment failure in resectable OTSCC. There is scope to further improve prognosis considering modest LRC and OS. Pathological T-stage, N-stage, and ECE are strong prognostic factors. Further research is required to confirm whether adjuvant therapy adds to treatment outcomes in cases with lymphovascular invasion, perineural invasion, and depth of invasion, and help clinicians tailoring adjuvant therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2731-2737
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• 2015

Background: The majority of deaths from cancer occur in low and middle income countries, partly due to poor public awareness of the signs and symptoms of cancer. Materials and Methods: A community based survey using the Cancer Awareness Measure (CAM) questionnaire was conducted in three different communities in Oman. Omani adults aged 18 years and above were invited to participate in the study. Results: A total of 345 responded from 450 invited participants (response rate=76.7%). The majority of respondents were unable to identify the common signs and symptoms of cancer identified in the CAM (average awareness was 40.6%). The most emotional barrier to seeking help was worry about what the doctor might find (223, 64.6%); a practical barrier was too busy to make an appointment (259, 75.1%) and a service barrier was difficulty talking to the doctor (159, 46.1%). The majority of respondents (more than 60% for seven out of ten symptoms) would seek medical help in two weeks for most signs or symptoms of cancer. Females were significantly more likely than males to be embarrassed (p<0.001), scared (p=0.001), and lack confidence talking about their symptoms (p=0.022). Conclusions: Urgent strategies are needed to improve public awareness of the signs and symptoms of cancer in Oman. This might leads to earlier diagnosis, improved prognosis and reduced mortality from cancer.

• Physical Therapy Korea
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• v.15 no.2
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• pp.44-53
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• 2008

The purpose of this preliminary study was to develop a measurement for assessing risk factors for falling in community-dwelling elderly persons. Rasch analysis and principal component analysis were performed to examine whether items on the Activities-Specific Balance Confidence (ABC), assessing self-efficacy, and items on the Berg Balance Scale (BBS), assessing balance function, contribute jointly to a unidimensional construct in the elderly. A total of 35 elderly persons (4 men, 31 women) participated. In this study, each item of ABC (16 items) and BBS (14 items) was scored on a 5-point ordinal rating scale from 0 to 4. The initial Rasch and principal component analysis indicated that 3 of the ABC items and 2 of the BBS items were misfit for this study. These 5 items were excluded from further study. After combining ABC and BBS, Rasch and principal component analyses were examined and finally 23 items selected; 12 items from ABC, 11 items from BBS. The 23 combined ABC-BBC items were arranged in order of difficulty. The hardest item was 'walk outside on icy sidewalks' and the easiest item was 'pivot transfer'. Although structural calibration of each 5 rating scale categories was not ordered, the other three essential criteria of Linacre's optimal rating scale were satisfied. Overall, the ABC-BBS showed sound item psychometric properties. Each of the 5 rating scale categories appeared to distinctly identify subjects at different ability levels. The findings of this study support that the new ABC-BBS scale measure balance function and self-efficacy. It will be a clinically useful assessment of risk factors for falling in the elderly. However, the number of subjects was too small to generalize our results. Further study is needed to develop a new assessment considering more risk factors of falling in elderly.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.5
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• pp.113-118
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• 2015

Mobile wireless networks have received a lot of attention as a future wireless network due to its rapid deployment without communication infrastructure. In these networks communication path between two arbitrary nodes break down because some links in the path are beyond transmission range($r_0$) due to the mobility of the nodes. The set of total path break down time(${\bigcup}T_i$), which is the union of path break down time of every node pair, can be a good measure of the connectivity of the dynamic mobile wireless network. In this paper we show that the distribution of the total path break down time can be approximated as a exponential probability density function and confirms it through experimental data. Statistical knowledge of break down time enables quantitative prediction of delay, packet loss between two nodes, thus provides confidence in the simulation results of mobile wireless networks.

• Imaging Science in Dentistry
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• v.45 no.1
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• pp.41-47
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• 2015

Purpose: This study was performed to evaluate the linear distance accuracy and reliability of stitched small field of view (FOV) cone-beam computed tomography (CBCT) reconstructed images for the fabrication of implant surgical guides. Material and Methods: Three gutta percha points were fixed on the inferior border of a cadaveric mandible to serve as control reference points. Ten additional gutta percha points, representing fiduciary markers, were scattered on the buccal and lingual cortices at the level of the proposed complete denture flange. A digital caliper was used to measure the distance between the reference points and fiduciary markers, which represented the anatomic linear dimension. The mandible was scanned using small FOV CBCT, and the images were then reconstructed and stitched using the manufacturer's imaging software. The same measurements were then taken with the CBCT software. Results: The anatomic linear dimension measurements and stitched small FOV CBCT measurements were statistically evaluated for linear accuracy. The mean difference between the anatomic linear dimension measurements and the stitched small FOV CBCT measurements was found to be 0.34 mm with a 95% confidence interval of +0.24 - +0.44 mm and a mean standard deviation of 0.30 mm. The difference between the control and the stitched small FOV CBCT measurements was insignificant within the parameters defined by this study. Conclusion: The proven accuracy of stitched small FOV CBCT data sets may allow image-guided fabrication of implant surgical stents from such data sets.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.4 s.38
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• pp.53-60
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• 2006

The purpose of this paper is forcasting of flooding area using LiDAR surveying data, and flood map for damage prevention is established for this purpose. Teahwa river at Ulsan city was chosen as test area and the flood simulation was produced in this area. For the flood simulation, each DEM using LiDAR data and digital map was established and then HEC model program and MIKE program was used to decide the amount of flood flowing and flood height. To improve the rainfall-overflow simulation confidence using inspection comparison of LiDAR data this paper analyzed and compared the LiDAR DEM accuracy and 1/5000 digital map DEM. The height accuracy is important factor to make flood map, however, LiDAR survey execution of all river area is not economic so, LiDAR survey execution of only important area is possible to be make high accuracy and economic flood map. The expectation effect of flood simulation is flood damage prevention and economic savings of recovery cost by forcasting of rainfall-overflow area and establishment of counter-measure.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.32-40
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• 2014

While there is a great demand for malware classification to reduce the time required in malware analysis and find a new type of malware, various similarity measurement methods of malware to classify a lot of malwares have been proposed. But, the existing methods to measure similarity just represented the classification results by them and have not carried out performance comparison with other methods. This is because an evaluation model to compare the performance of similarity measurement methods is non-existent. In this paper, we propose a new performance evaluation model on similarity measurement methods of malware by using two indicators: success rate and degree of confidence. In addition, we compare and evaluate the performance of existing similarity measurement methods by using these two indicators.

• Journal of Preventive Medicine and Public Health
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• v.48 no.6
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• pp.287-300
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• 2015

Objectives: Self-rated health is a measure of perceived health widely used in epidemiological studies. Our study investigated the determinants of poor self-rated health in middle-aged Korean adults with diabetes. Methods: A cross-sectional study was conducted based on the Health Examinees Study. A total of 9759 adults aged 40 to 69 years who reported having physician-diagnosed diabetes were analyzed with regard to a range of health determinants, including sociodemographic, lifestyle, psychosocial, and physical variables, in association with self-rated health status using multivariate logistic regression models. A p-value <0.05 was considered to indicate statistical significance. Results: We found that negative psychosocial conditions, including frequent stress events and severe distress according to the psychosocial well-being index, were most strongly associated with poor self-rated health (odds ratio $[OR]_{\text{Frequent stress events}}$, 5.40; 95% confidence interval [CI], 4.63 to 6.29; $OR_{\text{Severe distress}}$, 11.08; 95% CI, 8.77 to 14.00). Moreover, younger age and being underweight or obese were shown to be associated with poor self-rated health. Physical factors relating to participants' medical history of diabetes, such as a younger age at diagnosis, a longer duration of diabetes, insulin therapy, hemoglobin A1c levels of 6.5% or more, and comorbidities, were other correlates of poor reported health. Conclusions: Our findings suggest that, in addition to medical variables, unfavorable socioeconomic factors, and adverse lifestyle behaviors, younger age, being underweight or obese, and psychosocial stress could be distinc factors in predicting negative perceived health status in Korean adults with diabetes.

• Journal of Preventive Medicine and Public Health
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• v.50 no.2
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• pp.100-126
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• 2017

Objectives: The aim of this study was to measure income differences in smoking prevalence at the district level and to investigate correlations among area deprivation, smoking prevalence, and income differences in smoking prevalence, stratified by urbanity. Methods: Data were pooled from the Community Health Survey data of South Korea between 2008 and 2014. The age-standardized prevalence of smoking and its interquintile income differences were calculated. We conducted correlation analyses to investigate the association of the deprivation index with smoking prevalence and interquintile differences in smoking prevalence. Results: Across 245 districts, the median prevalence of smoking in men was 45.9% (95% confidence interval [CI], 43.4 to 48.5%), with an interquartile range (IQR) of 4.6% points. In women, the median prevalence was 3.0% (95% CI, 2.4 to 3.6%) and IQR was 1.6% points. The median interquintile difference in smoking prevalence was 7.4% points (95% CI, 1.6 to 13.2% points) in men and 2.7% points (95% CI, 0.5 to 4.9% points) in women. The correlation coefficients for the association between the deprivation index and smoking prevalence was 0.58, 0.15, -0.22 in metropolitan, urban, and rural areas, respectively, among men, and 0.54, -0.33, -0.43 among women. No meaningful correlation was found between area deprivation and interquintile difference in smoking prevalence. The correlation between smoking prevalence and interquintile difference in smoking prevalence was more evident in women than in men. Conclusions: This study provides evidence of geographical variations in smoking prevalence and interquintile difference in smoking prevalence. Neither smoking prevalence nor the deprivation index was closely correlated with interquintile income difference in smoking prevalence. Measuring inequalities in smoking prevalence is crucial to developing policies aimed at reducing inequalities in smoking.