• Journal of Korean Society of Disaster and Security
• /
• v.15 no.1
• /
• pp.1-12
• /
• 2022

An automatic optimization technique is used to estimate the optimal parameters of the hydrologic model, and different hydrologic response results can be provided depending on objective functions. In this study, the parameters of the event-based rainfall-runoff model were estimated using various objective functions, the reproducibility of the hydrograph according to the objective functions was evaluated, and appropriate objective functions were proposed. As the rainfall-runoff model, the storage function model(SFM), which is a lumped hydrologic model used for runoff simulation in the current Korean flood forecasting system, was selected. In order to evaluate the reproducibility of the hydrograph for each objective function, 9 rainfall events were selected for the Cheoncheon basin, which is the upstream basin of Yongdam Dam, and widely-used 7 objective functions were selected for parameter estimation of the SFM for each rainfall event. Then, the reproducibility of the simulated hydrograph using the optimal parameter sets based on the different objective functions was analyzed. As a result, RMSE, NSE, and RSR, which include the error square term in the objective function, showed the highest accuracy for all rainfall events except for Event 7. In addition, in the case of PBIAS and VE, which include an error term compared to the observed flow, it also showed relatively stable reproducibility of the hydrograph. However, in the case of MIA, which adjusts parameters sensitive to high flow and low flow simultaneously, the hydrograph reproducibility performance was found to be very low.

• Journal of the Korean Orthopaedic Association
• /
• v.56 no.6
• /
• pp.512-518
• /
• 2021

Purpose: This study compared the change in foraminal space on magnetic resonance imaging (MRI) and the clinical outcome after anterior cervical discectomy and fusion (ACDF) versus foraminotomy in cervical foraminal stenosis. Materials and Methods: A retrospective case-control study was conducted from January 2018 to March 2019 on 186 patients who underwent ACDF and foraminotomy. One hundred and two cases were selected considering age, sex, and body mass index. MRI was performed before and on the 5^th day after surgery to compare the changes in the foraminal diameter between the ACDF group (group A-51) and foraminotomy group (group B-51). Results: Between groups A and B, the average change in foraminal vertical diameter was 1.7 mm and 1.2 mm, respectively; group A was 0.5 mm larger difference (p=0.042). The average change in foraminal transverse diameter was 1.2 mm and 1.8mm, respectively; group B showed a 0.6 mm larger change (p=0.21). Both the neck disability index (NDI) and Japanese orthopaedic association (JOA) scores improved in both groups. Group A showed more improvement, but there was no significant difference (p=0.356, p=0.607, respectively). Conclusion: Foraminotomy is a useful option for patients with foraminal stenosis of the cervical spine because it showed comparable clinical and morphological results to ACDF and could minimize motion segment loss and muscle and ligament damage.

• Journal of the Korean Orthopaedic Association
• /
• v.54 no.6
• /
• pp.519-527
• /
• 2019

Purpose: To evaluate the treatment result in polyostotic fibrous dysplasia classified according to the involvement of the femoral head. Materials and Methods: Twenty-three patients from March 1987 to March 2014 were reviewed retrospectively. Patients with no involvement of the physeal scar in the femoral head were classified as Type I, and those with involvement of the physeal scar were classified as Type II. A plain radiograph was used to measure the femoral neck shaft angle, articulo-trochanteric distance (ATD), and anterior bowing through the lateral view. A teleoroentgenogram of the lower limb was used to measure the leg length discrepancy and lower extremity mechanical axis. The pre- and postoperative femoral neck-shaft angle and ATD were compared to assess the degree of correction of the deformity. Results: Among a total of 46 cases (23 patients), 28 cases (23 patients) had lesions in the proximal femur. Type I were 16/28 cases (15/23 patients) and Type II were 12/28 cases (9/23 patients). The preoperative proximal femoral neck-shaft angle was 116.8° in Type I and 95.3° in Type II. The ATD was 12.08 mm in Type I and -5.54 mm in Type II. The deformity correction showed significant improvement immediately after surgery, the deformity correction was lost in Type II (neck shaft angle Type I: 133.8°-130.8°, Type II: 128.6°-116.9°, and ATD Type I: 17.66-15.72 mm, Type II: 7.44-4.16 mm). The extent of anterior bowing was 12.74° in Type I and 20.19° in Type II. The mean differences of 12 mm between the 9 patients who showed a leg length discrepancy and the lower extremity mechanical axis showed 4 cases of lateral deviation and 7 cases of medial deviation. Conclusion: In polyostotic fibrous dysplasia, when the femur head is involved, the femur neck shaft angle, ATD, and anterior bowing of the femur had more deformity, and the postoperative correction of deformity was lost, suggesting that the involvement of the femoral head was an important factor in the prognosis of the disease.

• Advances in pediatric surgery
• /
• v.8 no.2
• /
• pp.143-155
• /
• 2002

A survey on biliary atresia was made among 26 members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and a case registration form for each patient during the twentyone-year period of 1980-2000. Three hundred and eighty patients were registered from 18 institutions. The average number of patients per surgeon was one to two every year. The male to female ratio was 1:1.3. The age of patients on diagnosis with biliary atresia was on average $65.4{\pm} 36.2$ days old. The national distribution was 32.8% in Seoul, 25.3% in Gyoungki-Do, 21.6% in Gyoungsang-Do, 9.27% in Choongchung-Do, etc. in order. The most common clinical presentation was jaundice (98.4%) and change of stool color (86.2%) was second. Two hundred eighty (74.7%) of 375 patients were operated by 80 days of age. Three hundred thirty six (9 1.9%) of 366 patients were operated on by the original Kasai procedure, and 305 (84.3%) of 362 patients were observed by bile-drainage postoperatively. The overall postoperative complication rate was 18.5% and the overall postoperative mortality rate was 6.8%. The associated anomalies were observed in 72 cases (22.5%). One hundred ninty five (64.7%) of 302 patients have been alive in follow-up and 49 (25.1%) have survived over 5 years without problem after operation. Ascending cholangitis, varices and ascites affected survival significantly, and the important long-term prognostic factor was the occurrence of complications.

• Clinical and Experimental Pediatrics
• /
• v.48 no.4
• /
• pp.376-379
• /
• 2005

Purpose : Mycoplasama pneumoniae is a leading cause of pneumonia and exacerbates other respiratory conditions such as asthma. Surfactant protein A(SP-A) is involved in surfactant physiology and surfactant structure, and plays a major role in innate host defense and inflammatory processes in the lung. In this study, SP-A mediated mycoplasma cidal activity. The candidate-gene approach was used to study the association between the SP-A gene locus and Mycoplasama pneumoniae pneumonia in the genetically homogeneous Korean population. Methods : PCR-cRFLP-based methodology was used to detect SP-A genotype. The forty nine children with Mycoplasama pneumoniae pneumonia were matched to 50 nomal neonates. Results : The specific frequencies for the alleles of the SP-A1 and SP-A2 gene in the study population were : $6A^2=21$ percent, $6A^3=45$ percent, $6A^4=11$ percent, $6A^8=9$ percent, $6A^{14}=8$ percent, 1A=11.3 percent, $1A^0=38$ percent, $1A^1=12.7$ percent, $1A^2=9.2$ percent, $1A^5=15.5$ percent, $1A^7=2.9$ percent, $1A^8=4.9$ percent, $1A^9=2.2$ percent, others=3.3 percent. The frequencies of specific genotypes such as $1A^2$ was higher than control group, significantly. Conclusion : $1A^2$ are susceptible factors for Mycoplasama pneumoniae pneumonia. We conclude that the SP-A gene locus($1A^2$) is an important determinant for predisposition to Mycoplasama pneumoniae pneumonia in children.

• Korean Journal of Environment and Ecology
• /
• v.30 no.3
• /
• pp.399-405
• /
• 2016

This study aimed to determine the total amount of carbon stored in the aboveground, belowground tree biomass, dead trees, and organic matter in the forest floor and soil of the 36-year-old Pinus rigida stands in Muju. A total of three plots were selected to measure the carbon stored in live trees, dead trees, forest floor, and soil. Results showed that the carbon stocks of P. rigida stands amounted to 51.0 ton C/ha in aboveground biomass and 29.6 ton C/ha in belowground biomass. The distribution ratios of carbon stocks were as follows: 41.0% in stem wood, 36.8% in roots, 12.8% in branches, 6.0% in stem bark and 3.4% in foliage. The carbon stocks in dead tree amounted to 0.65 ton C/ha while it was 6.40 ton C/ha in organic matter in forest floor. The total amount of carbon stocks found in soil was 51.62 ton C/ha: 20.27 ton C/ha at 0~10 cm depth, 12.83 ton C/ha at 10~20 cm depth, 12.27 ton C/ha at 20~30 cm depth, and 6.24 ton C/ha at 30~50 cm depth. It was also observed that, as the soil depth increased, the soil carbon stocks tended to decrease. Results showed that the total amount of carbon stocks of P. rigida stands in Muju was 139.27 ton C/ha; the highest portion of the cumulative carbon stocks was found to be in soil at 37.1%, followed by the aboveground biomass with 36.6%, belowground biomass with 21.3%, forest floor with 4.6 % and dead trees with 0.5 %. This study is expected to provide forest managers accurate estimates of carbon stored in the habitat of P. rigida stands in Muju.

• Journal of Korean Dental Hygiene Science
• /
• v.2 no.2
• /
• pp.31-39
• /
• 2019

Background: The purpose of this study was to investigate the effect of self-perception of halitosis on oral health behaviors of college students according to whether they worked in a non-service or service-related job. Methods: A self-reporting questionnaire of 150 university students working in service jobs and 150 university students working in non-service jobs in the metropolitan area was conducted from 26th April to 5th May 2018. The survey tool consisted of 3 general topic areas. There were 5 questions on oral health awareness behavior, 3 questions related to their self-perception of halitosis, and 8 questions on their oral health care practice. All were measured on the Likert 5-point scale. The frequency of their oral health behaviors and their self-perception of halitosis were analyzed according to the subjects' occupation. Pearson's correlation analysis and a linear regression analysis were conducted to confirm the influence of the two. The significance level for the statistical significance test was set to α = 0.05 (two-tailed). Results: In both the service and non-service groups, a coated tongue and food debris were found to influence halitosis(x²=10.95, p=0.027). According to the t-test, taking into account the self-perception of halitosis and oral health behaviors, both were higher in those that had a service job. Self-perception of halitosis and oral health behaviors were found to have a negative correlation(γ=-0.11, p<0.05). As the self-perception of halitosis increased, oral health care practices also increased(Beta=-0.185, p=0.020). Conclusions: Systematic interventions such as oral health programs and health promotion are needed to improve the oral health of service workers.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.11 no.1
• /
• pp.39-47
• /
• 2009

The importance of securing water resources and their efficient management has attracted more attention recently due to water deficit. In water budget analysis, however, evapotranspiration(${\lambda}E$) has been approximated as the residual in the water balance equation or estimated from empirical equations and assumptions. To minimize the uncertainties in these estimates, it is necessary to directly measure ${\lambda}E$. In this study, using the eddy covariance technique, we have measured ${\lambda}E$ in a mixed forest in the Seolmacheon catchment in Korea from September 2007 to December 2008. During the growing season(May-July), ${\lambda}E$ in this mixed forest averaged about $2.2\;mm\;d^{-1}$, whereas it was on average $0.5\;mm\;d^{-1}$ during the non-growing season in winter. The annual total ${\lambda}E$ in 2008 was $581\;mm\;y^{-1}$, which is about 1/3 of the annual precipitation of 1997 mm. Despite the differences in the amount and frequency of precipitation, the accumulated ${\lambda}E$ during the overlapping period(i.e., September to December) for 2007 and 2008 was both ${\sim}110$ mm, showing virtually no difference. The omega factor, which is a measure of decoupling between forest and the atmosphere, was on average 0.5, indicating that the contributions of equilibrium ${\lambda}E$ and imposed ${\lambda}E$ to the total ${\lambda}E$ were about the same. The results suggest that ${\lambda}E$ in this mixed forest was controlled by various factors such as net radiation, vapor pressure deficit, and canopy conductance. In this study, based on the direct measurements of ${\lambda}E$, we have quantified the relative contribution of ${\lambda}E$ in the water balance of a mixed forest in the Seolmacheon catchment. In combination with runoff data, the information on ${\lambda}E$ would greatly enhance the reliability of water budget analysis in this catchment.

• Tuberculosis and Respiratory Diseases
• /
• v.65 no.1
• /
• pp.7-14
• /
• 2008

Background: Residual pleural thickening (RPT) is the most frequent complication of tuberculous pleurisy (TP), and this can happen despite of administering adequate anti-tuberculous (TB) therapy. Yet there was no definite relation between RPT and other variables. The aim of this study was to examine matrix metalloproteinases (MMPs) and the inhibitors of metalloproteinases (TIMPs) and to identify the factors that can predict the occurrence of RPT. Methods: The patients with newly-detected pleural effusions were prospectively enrolled in this study from January 2004 to June 2005. The levels of MMP-1, -2, -8 and -9, and TIMP-1 and -2 were determined in the serum and pleural fluid by ELISA. The residual pleural thickness was measured at the completion of treatment and at the point of the final follow-up with the chest X-ray films. Results: The study included 39 patients with pleural fluid (PF). Twenty-three had tuberculous effusion, 7 had parapneumonic effusion, 7 had malignant effusion and 2 had transudates. For the 17 patients who completed the anti-TB treatment among the 23 patients with TP, 7 (41%) had RPT and 10 (59%) did not. The level of PF TIMP-1 in the patients with RPT ($41,405.9{\pm}9,737.3ng/mL$) was significantly higher than that of those patients without RPT ($29,134.9{\pm}8,801.8$) at the completion of treatment (p=0.032). In 13 patients who were followed-up until a mean of $8{\pm}5$ months after treatment, 2 (15%) had RPT and 11 (85%) did not. The level of PF TIMP-2 in the patients with RPT ($34.4{\pm}6.5ng/mL$) was lower than that of those patients without RPT ($44.4{\pm}15.5$) at the point of the final follow-up (p=0.038). Conclusion: The residual pleural thickening in TP might be related to the TIMP-1 and TIMP-2 levels in the pleural fluid.

• Journal of agricultural medicine and community health
• /
• v.29 no.1
• /
• pp.133-145
• /
• 2004

Objectives: Depression is a major health concern that can be life threatening if not recognized and treated early. However, there is few report on the depressive disorder of Hansen disease patients in Korea. Therefore, the authors executed this study in order to check factors related to a depressive disorder of a Hansen disease patients and compare with factors to reach to a depressive symptoms of ordinary people with studying their life state and the trouble that Hansen disease patients were currently experiencing Method: The authors surveyed depressive symptoms using self-reported questionnaires in 74 Hansen disease patients and 84 controls. The severity of depressive symptoms was measured using Korean Form of Geriatric Depression Scale (KGDS) score. Result: Positive rate of depressive disorders among Hansen disease patients was 70.3% and that the referents was 31.0%. There is significant difference positive rate of depressive disorders between Hansen disease group and the referents in the factors such as gender, age, frequency of going out, familial type, and familial income. Depressive disorder of Hansen disease group was associated with sex, familial income. According to the multiple logistic regression, the odds ratios of the Hansen disease group versus referents, gender, familial income, frequency of going out were significant (p<0.05). Conclusion: Hansen disease patients had statistically significant higher depressive symptom score than the referents. Also, Hansen disease patients who have lower familial income were more likely to have depressive disorders. Therefore, Economical supports and policy are required for the Hansen disease patients.