• Journal of Korean Society of Transportation
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• v.20 no.7
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• pp.107-116
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• 2002

Crash Cushion is a kind of safety facilities on roadside which acts the role of absorbing impact energy when vehicles are driven out of normal route such as Gore area of freeway off ramp. Criteria for severity index considering accident occurrence possibility are needed to have strong effect on installing the facilities. However, present criteria for establishing crash cushion design do not include such processes. Therefore, the paper presents two kinds of study to develop criteria for severity index. First of all, development of accident forecasting model on freeway off ramp is presented. The module is a relationship between accidents and road environment by negative binomial distribution (NB) which is called to reflect very well quality of accidents at Gore of crash cushion installed freeway Secondly, freeway exiting behavior model is developed because the human factor is the most important one. However, many literatures have shown between road environment and accidents which are more quantitative than human factor. The study supposed advanced process steps on actual freeway and analysed correlation between variables and accidents. The criteria for severity index is presented to determine whether to install or not by benefit cost analysis for each module. The standard for severity index will help to determine whether to install the crash cushion or not and to estimate severity for freeway and off ramp.

• Journal of Korea Water Resources Association
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• v.54 no.11
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• pp.925-932
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• 2021

A drought-flood abrupt alternation event is an overlapping extreme event that is harder to cope with than a single event of drought and flood. It is also expected to have a significant adverse impact on ecosystems as well as industries and agriculture. However, there has not yet been a comprehensive study that characterizes the drought-flood abrupt alternation events in Korea. Therefore, this study employed a standard weighted average precipitation (SWAP) index, which is efficient to analyze not only individual events of drought and flood but also the drought-flood abrupt alternation events considering various time scales. The SWAP standardized the weighted average precipitation (WAP) by adding temporal weights to the precipitation. The SWAP indices were calculated for middle-sized watersheds of the Han River basin using the area average precipitation during 1966 and 2018. The severity K was calculated to represent the relative regional severity considering normal rainfalls, and used to characterize the drought-flood abrupt alternation in the study areas. The results indicated that 20 of the 30 middle-sized watersheds in the Han River basin were confirmed to increase the severity of drought-flood abrupt alternation over time. Considering the frequency and severity of drought-flood abrupt alternation events in each watershed, vulnerable areas and dangerous areas due to drought-flood abrupt alternation were identified, for example, the Upstream Namhan River (#1001).

• KCID journal
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• v.3 no.1
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• pp.20-31
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• 1996

Several drought indices, which indicate the severity of drought in a reservoir or an irrigated area, have been suggested in home and overseas. However, the indices have not been adopted because those were extremely difficult to be understood by the genera

• Neonatal Medicine
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• v.25 no.3
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• pp.102-108
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• 2018

Purpose: Congenital diaphragmatic hernia (CDH) is rare but potentially fatal. The overall outcome is highly variable. This study aimed to identify a simple and dynamic parameter that helps predict the mortality of CDH patients in real time, without invasive tests. Methods: We conducted a retrospective chart review of 59 CDH cases. Maternal and fetal information included the gestational age at diagnosis, site of defect, presence of liver herniation, and lung-to-head ratio (LHR) at 20 to 29 weeks of gestational age. Information regarding postnatal treatment, including the number of days until surgery, the need for inhaled nitric oxide (iNO), the need for extracorporeal membrane oxygenation (ECMO), and survival, was collected. The highest respiratory severity score (RSS) within 24 hours after birth was also calculated. Results: Statistical analysis showed that a younger gestational age at the initial diagnosis (P<0.001), a lower LHR (P=0.001), and the presence of liver herniation (P=0.003) were prenatal risk factors for CDH mortality. The RSS and use of iNO and ECMO were significant factors affecting survival. In the multivariate analysis, the only remaining significant risk factor was the highest preoperative RSS within 24 hours after birth (P=0.002). The area under the receiver operating characteristic curve was 0.9375, with a sensitivity of 91.67% and specificity of 83.87% at the RSS cut-off value of 5.2. The positive and negative predictive values were 82.14% and 92.86%, respectively. Conclusion: Using the RSS as a prognostic predictor with simple calculations will help clinicians plan CDH management.

• The Journal of Internal Korean Medicine
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• v.36 no.3
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• pp.308-322
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• 2015

Objectives: Whether there exists a distinct pathogenesis in subgroups of functional dyspepsia (FD), the classification of epigastric pain syndrome (EPS), and postprandial distress syndrome (PDS) remains controversial. We aimed to investigate the number of fungiform papillae (FP) in the subgroups of FD and its correlation with the severity of dyspepsia symptoms and spleen qi deficiency. Methods: Patients with FD were enrolled from August to November 2014. All patients were evaluated using a questionnaire and divided into 2 groups according to the Rome III criteria for FD. The severity of dyspepsia symptoms and spleen qi deficiency were separately assessed by Nepean Dyspepsia Index-Korean (NDI-K) version and Spleen qi deficiency questionnaire (SQDQ). The number of FP was measured on the anterior part of tongue, within an area of 9 mm ², using a digital cam Results: The NDI-K score, SQDQ score, and number of FP in the EPS group were significantly greater than those in the PDS group. Also, the EPS group had more patients diagnosed with spleen qi deficiency. The number of FP showed a significant positive correlation with epigastric pain and burning. Furthermore, the number of FP was significantly associated with the score of some items in NDI-K and SQDQ, even though not with the total score. Conclusions: Thus, measurement of the number of FP could be a new evaluation indicator for allocation into FD subtypes and to investigate the severity of dyspepsia symptoms and spleen Qi deficiency reflecting visceral hypersensitivity.

• Health Policy and Management
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• v.32 no.4
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• pp.356-367
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• 2022

Background: The emergence of new infectious diseases threatens public health, increasing socioeconomic damage, and national risks. This study aimed to develop an evidence-based risk assessment tool to quickly respond to new infectious diseases. Methods: The risk elements were extracted by reviewing the risk assessment methods of the World Health Organization, United States, Europe, United Kingdom, and Germany, and the validity and priority of elements were determined through expert meetings and Delphi surveys. Then, the scale and level for each risk element were defined and a final score calculation method according to the risk evaluation result was derived. The developed risk assessment tool was verified using data at the time of domestic transmission of an emerging infectious disease. Results: In case of spread of actual infectious diseases, priority is determined based on the criticality of the elements in each area of transmissibility and severity, from which the weighted score of the risk assessment is derived. Then, the risk score for each element was calculated by multiplying the average value of the risk evaluation by its weight and the evaluation risk assessment score for the two areas was calculated. At last, the final score is plotted in a matrix where the x-axis indicates the transmissibility and the y-axis the severity and plotted on the coordinate plane for time series use. Conclusion: With respect to transmissibility and severity, this risk assessment method to respond to new and re-emerging infectious diseases enables rapid and evidence-based evaluation by quantitatively and qualitatively assessing various risk elements.

• Anxiety and mood
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• v.8 no.1
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• pp.9-15
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• 2012

Objectives : The purpose of this study was to assess the health-related quality of life (HRQoL) for patients with panic disorder using EQ-5D and EQ-VAS, and to examine the relationship between health-related quality of life and clinical outcomes following treatment. Methods : 29 patients with panic disorder were recruited from the Seoul Metropolitan area and 20 patients were followed up after two months of outpatient treatment. The Panic Disorder Severity Scale (PDSS) was used to assess the severity of the panic disorder and the changes in symptoms. HRQoL was assessed with EQ-5D and EQ-VAS at baseline and at two months of treatment. Results : All enrolled panic disorder patients showed significantly impairment of HRQoL in view of the subscales of EQ-5D, EQ-VAS index scores. The severity of PDSS was correlated the HRQoL in the panic patients. After treatment, the EQ-5D, EQ-VAS index scores showed significant improvement. Conclusion : Panic disorder patients suffer from lower HRQoL as well as from symptoms of the disorder. They showed clinical improvement and a restored HRQoL with treatment. These outcomes suggest using the EQ-5D, EQ-VAS such as the HRQoL in the assessment of patients with panic disorder is essential.

• Journal of Korean Neurosurgical Society
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• v.65 no.4
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• pp.582-590
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• 2022

Objective : Hydrocephalus after intracerebral hemorrhage (ICH) is known to be related to poor prognosis and mortality. We analyzed predictors of permanent hydrocephalus in the patients with surgically treated supratentorial ICH. Methods : From 2004 to 2019, a total of 414 patients with surgically treated primary supratentorial ICH were included. We retrospectively analyzed age, sex, preexisting hypertension and diabetes, location and volume of ICH, presence and severity of intraventricular hemorrhage (IVH), and type of surgery. Results : Forty patients (9.7%) required shunt surgery. Concomitant IVH was higher in the 'shunt required' group (92.5%) than in the 'shunt not required' group (67.9%) (p=0.001). IVH severity was worse in the 'shunt required' group (13.5 vs. 7.5, p=0.008). Craniectomy (47.5%) was significantly high in the 'shunt required' group. According to multivariable analysis, the presence of an IVH was 8.1 times more frequent and craniectomy was 8.6 times more frequent in the 'shunt required' group. In the comparison between craniotomy and craniectomy group, the presence of an IVH was related with a 3.9 times higher (p=0.033) possibility and craniectomies rather than craniotomies with a 7-times higher possibility of shunt surgery (p<0.001). Within the craniectomy group, an increase in the craniectomy area by 1 cm² was correlated with a 3.2% increase in the possibility of shunt surgery (odds ratio, 1.032; 95% confidence interval, 1.005-1.061; p=0.022). Conclusion : Presence of IVH, the severity of IVH and decompressive craniectomy were related to the development of shunt dependent hydrocephalus in the patients with ICH. The increasing size of craniectomy was related with increasing rate of shunt requirement.

• Journal of Korean Neurosurgical Society
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• v.38 no.1
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• pp.41-46
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• 2005

Objective : A study of the histopathologic and neurobehavioral correlates of cortical impact injury produced by increasing impact velocity using the controlled cortical impact[CCI] injury model is studied. Methods : Twenty-four Sprague-Dawley rats [$200{\sim}250g$] were given CCI injury using a pneumatically driven piston. Effect of impact velocity on a 3mm deformation was assessed at 2.5m/sec [n=6], 3.0m/sec [n=6], 3.5m/sec [n=6], and no injury [n=6]. After postoperative 24hours the rats were evaluated using several neurobehavioral tests including the rotarod test, beam-balance performance, and postural reflex test. Contusion volume and histopathologic findings were evaluated for each of the impact velocities. Results : On the rota rod test, all the injured rats exhibited a significant difference compared to the sham-operated rats and increased velocity correlated with increased deficit [p<0.001]. Contusion volume increased with increasing impact velocity. For the 2.5, 3.0, and 3.5m/sec groups, injured volumes were $18.8{\pm}2.3mm^3$, $26.8{\pm}3.1mm^3$, and $32.5{\pm}3.5mm^3$, respectively. In addition, neuronal loss in the hippocampal sub-region increased with increasing impact velocity. In the TUNEL staining, all the injured groups exhibited definitely positive cells at pericontusional area. However, there were no significant differences in the number of positive cells among the injured groups. Conclusion : Cortical impact velocity is a critical parameter in producing cortical contusion. Severity of cortical injury is proportional to increasing impact velocity of cortical injury.

• Journal of The Korean Society of Emergency Medicine
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• v.29 no.5
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• pp.455-464
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• 2018

Objective: Machine learning is not yet widely used in the medical field. Therefore, this study was conducted to compare the performance of preexisting severity prediction models and machine learning based models (random forest [RF], gradient boosting [GB]) for mortality prediction in pneumonia patients. Methods: We retrospectively collected data from patients who visited the emergency department of a tertiary training hospital in Seoul, Korea from January to March of 2015. The Pneumonia Severity Index (PSI) and Sequential Organ Failure Assessment (SOFA) scores were calculated for both groups and the area under the curve (AUC) for mortality prediction was computed. For the RF and GB models, data were divided into a test set and a validation set by the random split method. The training set was learned in RF and GB models and the AUC was obtained from the validation set. The mean AUC was compared with the other two AUCs. Results: Of the 536 investigated patients, 395 were enrolled and 41 of them died. The AUC values of PSI and SOFA scores were 0.799 (0.737-0.862) and 0.865 (0.811-0.918), respectively. The mean AUC values obtained by the RF and GB models were 0.928 (0.899-0.957) and 0.919 (0.886-0.952), respectively. There were significant differences between preexisting severity prediction models and machine learning based models (P<0.001). Conclusion: Classification through machine learning may help predict the mortality of pneumonia patients visiting the emergency department.