• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4B
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• pp.309-314
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• 2011

Analysis of discharge characteristics through control gates at river crossing structures is important for an effective water level control and water resources management. In recent years, many river control structures in four major rivers are under construction but only few researches on discharge characteristics at control gates could be found in Korea. The discharge characteristics depend on both shape of control gates and the effects of downstream water-depth. In this research, classification index for discharge patterns (free weir, submerged weir, free orifice, submerged orifice) through a control gate were reviewed with $h_g/h_1$, $h_3/h_g$, and $h_3/h_1$. Classification criteria of discharge patterns were also suggested. Representative discharge estimation equations for each discharge patterns were adopted and discharge coefficients were developed from a hydraulic model for a specific control gate which will be constructed in Nakdong river. Reliability of the derived discharge equation and coefficients were confirmed by comparisons between the real discharge in a model and the predicted discharge from the results of this research.

• Journal of Korean Academy of Nursing Administration
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• v.13 no.1
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• pp.5-16
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• 2007

Purpose: This study is to verify the validity and reliability of classified items and criteria of the patient classification system(PCS) based on Park's definition of nursing intensity. Methods: An expert group of 8 persons verified the content validity of the tools. The 1817 inpatients at a tertiary hospital in Seoul, Korea were classified into 4 groups according to two tools for verifying concurrent validity and interraters' reliability. These verifications were performed from September to October, 2004. Results: Nursing domains of the tools have been divided into 12 items: hygiene, nutrition, elimination, exercise & activity, education & counseling, emotional support, communication & consciousness, treatment & examination, medication, measurement & observation, coordination of multidisciplinary team, admission & discharge & transfer management. Content validity was verified by the content validity index(above 0.75 in all 12 areas). Interraters' reliability was no significant difference in the results of the patient classification between the two raters(A group 93.75%. B group 88.24%). Concurrent validity was also verified by the agreement of two tools(73.7%). Conclusion: These results showed that the reliability and validity of the PCS based on the nursing intensity were verified. These will use an data for nursing productivity in the future.

• Korean Journal of Remote Sensing
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• v.34 no.6_3
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• pp.1319-1327
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• 2018

Korea has a terrain vulnerable to drought due to the concentration of precipitation in summer and the large amount of groundwater discharge. Quantified drought indices are used to determine these droughts. Among these, drought index is mainly used for analysis of precipitation, and recently, researches have been conducted to monitor drought using satellite images. In this study, we used the KOMPSAT-2/3 image to calculate the water surface area and compare with the drought index in order to monitor the drought in the Upper Soyang River. As a result, it was confirmed that the tendency of the water surface area change and the trend of the drought index were similar in the satellite images. Future research could be used as a basis for judging drought.

• Hip & pelvis
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• v.34 no.4
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• pp.227-235
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• 2022

Purpose: Outpatient classified total hip arthroplasty (THA) is a safe option for a select group of patients. An analysis of a national database was conducted to understand the risk factors for unplanned discharge to a skilled nursing facility (SNF) or acute rehabilitation (rehab) after outpatient classified THA. Materials and Methods: A query of the National Surgical Quality Improvement Program (NSQIP) database for THA (Current Procedural Terminology [CPT] 27130) performed from 2015 to 2018 was conducted. Patient demographics, American Society of Anesthesiologists (ASA) classification, functional status, NSQIP morbidity probability, operative time, length of stay (LOS), 30-day reoperation rate, readmission rate, and associated complications were collected. Results: A total of 2,896 patients underwent outpatient classified THA. The mean age of patients was 61.2 years. The mean body mass index (BMI) was 29.6 kg/m² with median ASA 2. The results of univariate comparison of SNF/rehab versus home discharge showed that a significantly higher percentage of females (58.7% vs. 46.8%), age >70 years (49.3% vs. 20.9%), ASA ≥3 (58.0% vs. 25.8%), BMI >35 kg/m² (23.3% vs. 16.2%), and hypoalbuminemia (8.0% vs. 1.5%) (P<0.0001) were discharged to SNF/rehab. The results of multivariable logistic regression showed that female sex (odds ratio [OR] 1.47; P=0.03), age >70 years (OR 3.08; P=0.001), ASA≥3 (OR 2.56; P=0.001), and preoperative hypoalbuminemia (<3.5 g/dL) (OR 3.76; P=0.001) were independent risk factors for SNF/rehab discharge. Conclusion: Risk factors associated with discharge to a SNF/rehab after outpatient classified THA were identified. Surgeons will be able to perform better risk stratification for patients who may require additional postoperative intervention.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.126-136
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• 2018

The purpose of this study was to develop a severity-adjustment model for predicting mortality in acute stroke patients using machine learning. Using the Korean National Hospital Discharge In-depth Injury Survey from 2006 to 2015, the study population with disease code I60-I63 (KCD 7) were extracted for further analysis. Three tools were used for the severity-adjustment of comorbidity: the Charlson Comorbidity Index (CCI), the Elixhauser comorbidity index (ECI), and the Clinical Classification Software (CCS). The severity-adjustment models for mortality prediction in patients with acute stroke were developed using logistic regression, decision tree, neural network, and support vector machine methods. The most common comorbid disease in stroke patients were hypertension, uncomplicated (43.8%) in the ECI, and essential hypertension (43.9%) in the CCS. Among the CCI, ECI, and CCS, CCS had the highest AUC value. CCS was confirmed as the best severity correction tool. In addition, the AUC values for variables of CCS including main diagnosis, gender, age, hospitalization route, and existence of surgery were 0.808 for the logistic regression analysis, 0.785 for the decision tree, 0.809 for the neural network and 0.830 for the support vector machine. Therefore, the best predictive power was achieved by the support vector machine technique. The results of this study can be used in the establishment of health policy in the future.

• The Journal of Korean Physical Therapy
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• v.4 no.1
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• pp.43-57
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• 1992

This study was conducted from August, 1980 to March, 9991 to the 40 subjects who were admitted to Kosin Medical Center and received rehabilitation treatment and discharged under the impression of stroke. The objectives are to evaluate the function of the activites of daily living and comprehensive function and find the status of rehabilitation treatment by Modified Barthel Index and PULSES Profile when first requested or rehabilitation treatment(T1), at 2 weeks after rehabilitation treatment(T2), at discharge(T3) and at the time of ambulatory treatment after 2 weeks(T4). The study materials were clinical charts and functional evaluation sheets, and the results are as follows : 21 subject$(52.5\%)$ were male, 19 subjects$(47.5\%)$ were female, and the age distribution was from 19 to 70 in age, the average age was 52.7. By the classification of diagnosis, 21 subjects$(52.5\%)$ were cerebral hemorrhage, 8 subjects$(20.2\%)$ were cerebral thrombosis, 6 subjects$(15.0\%)$ were cerebral embolism, and 5 subjects$(12.5\%)$ were cerebral infarction. The Barthel Index scores were 35.7, 54.5, 71.8, 88.7 on the average at T1, T2, T3, T4 respectively. The PULSES scores were 16.4, 13.7, 11.4, 8.7 on the average at T1, T2, T3, T4 respectively. Regarding the Pearson's correlation coefficient between the Barthel Index scores and the PULSES scores, it was -0.7991(P>0.001) at T1 and -0.8986(P>0.001) at T3, then beth of correlations were very high.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.217-230
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• 2019

This study was conducted to develop a customized severity-adjustment method and to evaluate their validity for acute myocardial infarction(AMI) patients to complement the limitations of the existing severity-adjustment method for comorbidities. For this purpose, the subjects of KCD-7 code I20.0 ~ I20.9, which is the main diagnosis of acute myocardial infarction were extracted using the Korean National Hospital Discharge In-depth Injury survey data from 2006 to 2015. Three tools were used for severity-adjustment method of comorbidities : CCI (charlson comorbidity index), ECI (Elixhauser comorbidity index) and the newly proposed CCS (Clinical Classification Software). The results showed that CCS was the best tool for the severity correction, and that support vector machine model was the most predictable. Therefore, we propose the use of the customized method of severity correction and machine learning techniques from this study for the future research on severity adjustment such as assessment of results of medical service.

• Tuberculosis and Respiratory Diseases
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• v.87 no.2
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• pp.176-184
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• 2024

Background: Results of studies investigating the association between body mass index (BMI) and mortality in patients with coronavirus disease-2019 (COVID-19) have been conflicting. Methods: This multicenter, retrospective observational study, conducted between January 2020 and August 2021, evaluated the impact of obesity on outcomes in patients with severe COVID-19 in a Korean national cohort. A total of 1,114 patients were enrolled from 22 tertiary referral hospitals or university-affiliated hospitals, of whom 1,099 were included in the analysis, excluding 15 with unavailable height and weight information. The effect(s) of BMI on patients with severe COVID-19 were analyzed. Results: According to the World Health Organization BMI classification, 59 patients were underweight, 541 were normal, 389 were overweight, and 110 were obese. The overall 28-day mortality rate was 15.3%, and there was no significant difference according to BMI. Univariate Cox analysis revealed that BMI was associated with 28-day mortality (hazard ratio, 0.96; p=0.045), but not in the multivariate analysis. Additionally, patients were divided into two groups based on BMI ≥25 kg/m² and underwent propensity score matching analysis, in which the two groups exhibited no significant difference in mortality at 28 days. The median (interquartile range) clinical frailty scale score at discharge was higher in nonobese patients (3 [3 to 5] vs. 4 [3 to 6], p<0.001). The proportion of frail patients at discharge was significantly higher in the nonobese group (28.1% vs. 46.8%, p<0.001). Conclusion: The obesity paradox was not evident in this cohort of patients with severe COVID-19. However, functional outcomes at discharge were better in the obese group.

• Journal of Korean Society on Water Environment
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• v.37 no.4
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• pp.249-262
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• 2021

This study investigated the pollution characteristics of the main pollution zone in the Hwangguji watershed and the influence of the tributary on the main stream. The characteristics of the main pollution zone, including, the water quality index (WQI), stream rating, load duration curve (LDC), delivery load density (DLD), and contribution of the tributary to the mainstream, were evaluated by time-series visual heatmap. The WQI of the mainstream of Hwangguji was lowered to the poor (IV) level from the inflow point of Suwon stream (SW) and the LDC excess rate in the T-P was higher than that of BOD₅, especially for the wet season, suggesting that management of non-point source with T-P is preferred. The contribution (%) of the tributaries in the upstream section of Hwangguji watershed were BOD₅ 14.54%, TOC 15.67%, T-N 5.43%, and T-P 6.97%. In particular, the Suwon sewage treatment plant located in the mainstream showed a high contribution of BOD₅ (64.40%) and T-P (53.54%), respectively, due to the high discharge rate (6.019 m³/sec). Meanwhile, Sammi and Gal stream have a large impact on the mainstream with high DLD and poor WQI. Thus, both streams were considered as pollution hot spots. These results provide useful basic data for preparing more effective water quality improvement and management plans in the watershed.

• Journal of Gastric Cancer
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• v.15 no.4
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• pp.262-269
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• 2015

Purpose: Intraabdominal abscess is one of the most common reasons for re-hospitalization after gastrectomy. This study aimed to develop a model for estimating the probability of intraabdominal abscesses that can be used during the postoperative period. Materials and Methods: We retrospectively reviewed the clinicopathological data of 1,564 patients who underwent gastrectomy for gastric cancer between 2010 and 2012. Twenty-six related markers were analyzed, and multivariate logistic regression analysis was used to develop the probability estimation model for intraabdominal abscess. Internal validation using a bootstrap approach was employed to correct for bias, and the model was then validated using an independent dataset comprising of patients who underwent gastrectomy between January 2008 and March 2010. Discrimination and calibration abilities were checked in both datasets. Results: The incidence of intraabdominal abscess in the development set was 7.80% (122/1,564). The surgical approach, operating time, pathologic N classification, body temperature, white blood cell count, C-reactive protein level, glucose level, and change in the hemoglobin level were significant predictors of intraabdominal abscess in the multivariate analysis. The probability estimation model that was developed on the basis of these results showed good discrimination and calibration abilities (concordance index=0.828, Hosmer-Lemeshow chi-statistic P=0.274). Finally, we combined both datasets to produce a nomogram that estimates the probability of intraabdominal abscess. Conclusions: This nomogram can be useful for identifying patients at a high risk of intraabdominal abscess. Patients at a high risk may benefit from further evaluation or treatment before discharge.