• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.327-335
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• 2020

The method of selecting an existing flood hazard area via a numerical model requires considerable time and effort. In this regard, this study proposes a method for selecting flood vulnerable areas through topographic analysis based on a surface runoff mechanism to reduce the time and effort required. Flood vulnerable areas based on runoff mechanisms refer to those areas that are advantageous in terms of the flow accumulation characteristics of rainfall-runoff water at the surface, and they generally include lowlands, mild slopes, and rivers. For the analysis, a digital topographic map of the target area (Seoul) was employed. In addition, in the topographic analysis, eight topographic factors were considered, namely, the elevation, slope, profile and plan curvature, topographic wetness index (TWI), stream power index, and the distances from rivers and manholes. Moreover, receiver operating characteristic analysis was conducted between the topographic factors and actual inundation trace data. The results revealed that four topographic factors, namely, elevation, slope, TWI, and distance from manholes, explained the flooded area well. Thus, when a flood vulnerable area is selected, the prioritization method for various factors as proposed in this study can simplify the topographical analytical factors that contribute to flooding.

• Food Science and Industry
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• v.54 no.2
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• pp.93-101
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• 2021

Hazard Analysis Critical Control Point (HACCP) systems were developed to ensure a high level of food safety and reduced risk of foodborne illness. This paper focuses on significant issues associated with the implementation of HACCP; it provides an overview on recent literature. The structure of the paper follows six groupings of issues in the international literature of HACCP: (1) comparative studies and unification plan between HACCP and other food safety regulations; (2) verification of the HACCP system's effectiveness in improving food safety; (3) establishment of critical control point (CCP) for various foods HACCP model development; (4) expansion of HACCP application in the various fields and small businesses;(5) the impacts of HACCP on consumer's preferences and firms' financial performance in food industry; (6) HACCP and technological changes. The paper concludes with some suggestions for the future research in order to promote safe food supply chain for global customers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.283-290
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• 2021

Survival analysis was used to determine whether there are differences in the impact of trade payables on business failure according to the size of the company. A total of 41,781 firms from 1999 to 2019 were analyzed. The analysis period was divided into the entire period and before and after the financial crisis. The trade payable ratio is a proxy variable. The increase in trade payables over the entire period increases the possibility of business failure of Small and Medium Enterprises (SMEs). However, in large firms, a significant relationship between the increase in the trade payable ratio and the possibility of corporate failure could not be confirmed. Second, in SMEs during the sub-periods of 1999-2007 and 2009-2019, it was found that an increase in trade payables acts as a factor that increases the possibility of corporate failure. However, in large corporations, the increase in trade payables in the period from 2009 to 2019 has been shown to reduce the rate of failure. An increase in trade payables is recognized as the active development of business activities or the active use of interest-free debt. Therefore, it was confirmed that the impact of trade payables on corporate failure differs depending on the size of the company.

• Korean Journal of Biological Psychiatry
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• v.28 no.1
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• pp.13-22
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• 2021

Objectives Despite growing attention to anxiety in bipolar disorder (BD), little research has assessed anxiety symptoms in the course of BD. The current prospective follow-up study examines the influence of subjectively and objectively measured anxiety symptoms on the course of BD. Methods A total of 49 patients with BD were followed-up prospectively for average of one year at an average of four months interval. The Korean version of the Beck Anxiety Inventory (K-BAI), the Hamilton Anxiety Rating Scale, heart rate variability (HRV) were used to measure anxiety subjectively, objectively and physiologically. Participants were divided into high and low anxiety groups based on their K-BAI scores. Kaplan-Meier survival analysis was performed to compare the recurrence of mood episode, suicide attempt, emergency room visit, and psychiatric hospitalization between two groups. Mediators were investigated with Cox proportional hazards models. Results Compared to the low anxiety group, the high anxiety group reported significantly higher impulsiveness (p = 0.016) and lower high frequency component on HRV (p = 0.007) after controlling for severity of BD. Regarding survival analysis, the high anxiety group showed hastened depressive episode recurrence (p = 0.048) and suicidal ideation was the mediator of the hazard ratio (HR) 1.089 (p = 0.029) in the Cox model. Moreover, the high anxiety group showed a tendency of accelerated suicide attempt (p = 0.12) and impulsivity was the risk factor of suicide attempt (HR = 1.089, p = 0.036). Conclusions This interim analysis of prospective study suggests that high anxiety level in BD may anticipate unfavorable course. Further studies are needed to understand the multifactorial mechanism of anxious bipolar patients.

• Journal of Chest Surgery
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• v.55 no.1
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• pp.10-19
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• 2022

Background: According to the eighth TNM (tumor-node-metastasis) staging system, the presence of separate tumor nodules in the same lobe is designated as a T3 descriptor. However, it remains unclear whether adjuvant chemotherapy confers survival advantages in this setting. Methods: We retrospectively identified 142 pathologic T3N0M0 patients with additional pulmonary nodules in the same lobe from a single-institutional database from 2004 to 2019. The main outcomes were overall survival and recurrence-free survival. Multivariable Cox regression was used to identify the benefit of adjuvant chemotherapy while adjusting for other variables. Results: Sixty-one patients received adjuvant chemotherapy (adjuvant group) and 81 patients did not receive adjuvant therapy after surgery (surgery-only group). There were no demonstrable differences between the 2 groups regarding hospital mortality and postoperative complications, indicating that treatment selection had not significantly occurred. However, the use of adjuvant chemotherapy was associated with improved 5-year overall survival (70% vs. 59%, p=0.006) and disease-free survival (60% vs. 46%, p=0.040). A multivariable Cox model demonstrated that adjuvant chemotherapy was associated with a survival advantage (adjusted hazard ratio, 0.54; p<0.001). In exploratory analyses of subgroups, the effect of adjuvant chemotherapy seemed to be insufficient in those with small main tumors (<4 cm). Conclusion: Adjuvant chemotherapy was associated with better survival in T3 cancers with an additional tumor nodule in the same lobe. However, the role of adjuvant chemotherapy in patient subgroups with small tumors or those without risk factors should be determined via large studies.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.121-126
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• 2022

This study analyzed the survival rate of commercial districts before and after the outbreak of COVID-19 by analyzing Gangnam-gu, Seoul and Suseong-gu, Daegu as independent regions, although the background and distribution of commercial districts are similar. In the basic analysis, the size of the commercial districts was much larger in Gangnam-gu, Seoul, but it was confirmed that the distribution by industry was similar. In both regions, there were more openings than closings before the outbreak of COVID-19 in common, but as the COVID-19 outbreak occurred, the closure ratio of businesses centered on face-to-face services increased significantly. As a result of the survival analysis, it was analyzed that most industries were indifferent to the risk of closure of private institutes before Corona 19, but after the outbreak of Corona 19, it was confirmed that the risk of closure of private institutes increased, especially in Daegu, which was the initial spread of Corona 19. As a result of comparing the survival rate between regions, it was analyzed that the risk of business closure in Gangnam-gu increased relatively after the outbreak of Corona 19, confirming that the contraction in the commercial area of Seoul with a large floating population was greater.

• Nutrition Research and Practice
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• v.16 no.5
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• pp.604-615
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• 2022

BACKGROUND/OBJECTIVES: This study aimed to investigate cancer-specific survival (CSS) and associated risk factors in elderly gastric cancer (EGC) patients. SUBJECTS/METHODS: EGC patients (≥ 70 yrs) who underwent curative gastrectomy between January 2013 and December 2017 at our hospital were included. Clinicopathologic characteristics and survival data were collected. Receiver operating characteristic (ROC) analysis was used to extract the best cutoff point for body mass index (BMI). A Cox proportional hazards model was used to determine the risk factors for CSS. RESULTS: In total, 290 EGC patients were included, with a median age of 74.7 yrs. The median follow-up time was 31 (1-77) mon. The postoperative 1-yr, 3-yr and 5-yr CSS rates were 93.7%, 75.9% and 65.1%, respectively. Univariate analysis revealed risk factors for CSS, including age (hazard ratio [HR] = 1.08; 95% confidence interval [CI], 1.01-1.15), intensive care unit (ICU) admission (HR = 1.73; 95% CI, 1.08-2.79), nutritional risk screening (NRS 2002) score ≥ 5 (HR = 2.33; 95% CI, 1.49-3.75), and preoperative prognostic nutrition index score < 45 (HR = 2.06; 95% CI, 1.27-3.33). The ROC curve showed that the best BMI cutoff value was 20.6 kg/m². Multivariate analysis indicated that a BMI ≤ 20.6 kg/m² (HR = 2.30; 95% CI, 1.36-3.87), ICU admission (HR = 1.97; 95% CI, 1.17-3.30) and TNM stage (stage II: HR = 5.56; 95% CI, 1.59-19.43; stage III: HR = 16.20; 95% CI, 4.99-52.59) were significantly associated with CSS. CONCLUSIONS: Low BMI (≤ 20.6 kg/m²), ICU admission and advanced pathological TNM stages (II and III) are independent risk factors for CSS in EGC patients after curative gastrectomy. Nutrition support, better perioperative management and early diagnosis would be helpful for better survival.

• Journal of Chest Surgery
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• v.56 no.3
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• pp.155-161
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• 2023

Background: Surgical closure of an atrial septal defect (ASD) is infrequently indicated during infancy. We evaluated the clinical characteristics and outcomes of patients who underwent surgical ASD closure during infancy. Methods: A single-center retrospective review was performed for 39 patients (19 males) who underwent surgical ASD closure during infancy between 1993 and 2020. The median body weight percentile at the time of operation was 9.3. Results: During a median follow-up of 60.9 months, 4 late deaths occurred due to chronic respiratory failure. A preoperative history of bronchopulmonary dysplasia (BPD) was the only risk factor for late mortality identified in Cox regression (hazard ratio, 3.54; 95% confidence interval [CI], 1.75-163.04; p=0.015). The 5-year survival rate was significantly lower in patients with preoperative history of BPD (97.0% vs. 50.0%, p<0.001) and preoperative ventilatory support (97.1% vs. 40.4%, p<0.001). There were significant postoperative increases in left ventricular end-diastolic (p=0.017), end-systolic (p=0.014), and stroke volume (p=0.013) indices. A generalized estimated equation model showed significantly better postoperative improvement in body weight percentiles in patients with lower weight percentiles at the time of operation (<10th percentile, p=0.01) and larger indexed ASD diameter (≥45 mm/m², p=0.025). Conclusion: Patients with ASD necessitating surgical closure during infancy are extremely small preoperatively and remain small even after surgical closure. However, postoperative somatic growth was more prominent in smaller patients with larger defects, which may be attributable to an increase in postoperative cardiac output due to changes in ventricular septal configuration. The benefits of ASD closure in patients with BPD are undetermined.

• Journal of Navigation and Port Research
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• v.47 no.1
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• pp.37-48
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• 2023

Recently, the increase of international trade volume is leading to risk exposure and safety accidents in the port terminal industry. In addition, as Serious Disaster Punishment Act came into effect on January, 2021, various guidelines and laws to protect safety and life in port terminals are being enacted. However, despite these efforts, medium-to-large safety accidents in the port terminal industry have occurred. According to the Korea Occupational Safety and Health Agency, from 2016 to 2019, the number of casualties in the port handling industry increased by 4.2%. To build some effective follow-up management of port accidents and preparation of related safety laws/systems, a risk analysis in consideration of causes and damage of accidents should be conducted. Therefore, in this study, major risk factors and preventive measures were derived by conducting risk assessment based on 1,039 cases of port terminal accidents collected by the Korea Occupational Safety and Health Agency for five years. Priorities for preventive measures were then determined through IPA analysis, Borich needs analysis, and The Locus For Focus analysis.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.273-275
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• 2022

The use of drugs by pregnant women poses a potential risk to the fetus. Therefore, it is essential to classify drugs that pregnant women should prohibit. However, the fetal toxicity of most drugs has not been identified. This takes a lot of time and cost. In silico approaches, such as virtual screening, can identify compounds that may present a high risk to the fetus for a wide range of compounds at the low cost and time. We collected class information of each drug from the hazard classification lists for prescribing drugs in pregnancy by the government of Korea and Australia. Using the structural and chemical features of each drug, various machine learning models were constructed to predict fetal toxicity of drugs. For all models, the quantitative performance evaluation was performed. Based on the attention algorithm, important molecular substructures of compounds were identified in the process of predicting the fetal toxicity of the drug by the proposed model. From the results, we confirmed that drugs with a high risk of fetal toxicity can be predicted for a wide range of compounds by machine learning. This study can be used as a pre-screening tool for fetal toxicity predictions, as it provides key molecular substructures associated with the fetal toxicity of compounds.