• Fire Science and Engineering
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• v.31 no.5
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• pp.107-116
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• 2017

Fires in tunnels are an international concern and fatal accidental fires in tunnels seem to occur on annual. They have the potential to become much worse int the future as more and longer tunnels are constructed and as traffic densities increase. This is a serious problem. The main purpose of this study is to develop operational procedures for fire brigades in road tunnel fires. This study discussed the past to see what can be learned from the incidents that have already done in tunnels. 73 cases of road tunnel fires domestic and outside of Korea were investigated and classified into 4 incident categories. Among them, 4 tunnel fires are highlighted, focusing on the activities of fire brigades and operation. Regarding the establishment of the strategies for fire fighting, 6 kinds of fire scenario curves have been deducted with regard to the relation between intervention time and heat release rate. It made the choice from the defensive or aggressive fire fighting activities depending on two criteria i.e. response limit and maximum response time. Road Tunnel Classification models can be useful when a fire brigade evaluates fire risk levels in the tunnels under its jurisdiction from the firefighting point of view and sets up preventive measures.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.6
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• pp.768-773
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• 2012

One of the main reasons for serious road accidents is driving while drowsy. For this reason, drowsiness detection and warning system for drivers has recently become a very important issue. Monitoring physiological signals provides the possibility of detecting features of drowsiness and fatigue of drivers. One of the effective signals is to measure electroencephalogram (EEG) signals and electrooculogram (EOG) signals. The aim of this study is to extract drowsiness-related features from a set of EEG signals and to classify the features into three states: alertness, drowsiness, sleepiness. This paper proposes a drowsiness detection system using Linear Predictive Coding (LPC) coefficients and Support Vector Machine (SVM). Samples of EEG data from each predefined state were used to train the SVM program by using the proposed feature extraction algorithms. The trained SVM program was tested on unclassified EEG data and subsequently reviewed according to manual classification. The classification rate of the proposed system is over 96.5% for only very small number of samples (250ms, 64 samples). Therefore, it can be applied to real driving incident situation that can occur for a split second.

• Journal of the Korean Solar Energy Society
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• v.31 no.2
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• pp.89-98
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• 2011

This study examined the energy performance according to the main design parameters of a solar water heating system for an office building using the life cycle cost (LCC) optimization simulations. The LCC optimization simulations of the system were conducted with TRNSYS and GenOpt employing the Hooke-Jeeves algorithm for cases where water temperature was $60^{\circ}C$ and $50^{\circ}C$. The results showed that for water temperature at $60^{\circ}C$ and $50^{\circ}C$ the global radiation incident on the collector could be decreased by 16.98% and 28.52%, collector useful energy gain could be decreased by 15.04% and 22.59%, energy to load from storage tank could be decreased by 10.86% and 18.06% and AH energy to load could be increased by 16.86% and 38.50% respectively compared to a non-optimized system. The annual average collection efficiency of the collector was increased by 0.88% for $60^{\circ}C$ and 2.78% for $50^{\circ}C$ because of increase of collector slope and decrease of the mass flow rate per collector area. The annual average efficiency of the system was increased by 1.74% and 3.47% compared to the basis system. However, the annual solar fraction of the system was decreased by 6.68% for $60^{\circ}C$ and 11.26% for $50^{\circ}C$ due to decrease of collector area and storage tank volume.

• Journal of Navigation and Port Research
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• v.45 no.6
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• pp.325-332
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• 2021

As commercial and residential areas are actively developed around the coastal area with excellent scenery, installing coastal structures such as seawalls and breakwaters is continuously increasing to secure safe coastal regions. Additionally, the increase in the intensity of natural disasters due to climate change may cause higher incident waves than in the past, which may further aggravate the damage caused by wave overtopping. In this study, compared to the existing vertical seawall, we investigated the effect of wave overtopping reduction of a recurved seawall, which actively reflects the incoming waves, through the hydraulic model test. As a result of the hydraulic model experiment, it was confirmed that there was an effect of up to 92.4% of wave overtopping reduction in average compared to the vertical seawall and structures covered with armor blocks.

• Quality Improvement in Health Care
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• v.24 no.2
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• pp.2-14
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• 2018

Purpose: The objective of this study was to report the incidence of falls in hospitals and analyze the risk factors for falls. Methods: This study used data on 1,216 patients who experienced falls from 2015 to 2017 during their hospitalization. The data was collected from the falls incident reports and patient' electronic medical record of hospital. Data were analyzed with descriptive statistics using Chi-square test, Fisher's exact test and multiple Poisson regression analysis with the SAS 9.4 Results: The incidence of falls was 1.38 per 1,000 patients days (2015), 1.81 per 1,000patients days (2016) and 1.99 per 1,000patients days (2017). The incidence of injury caused by falls (level III~V) was 0.05 per 1,000patients days (2015), 0.04 per 1,000patients days (2016) and 0.06 per 1,000patients days (2017). The largest number of falls occurred during night shift (42.5%), specifically in the patients' room (70.8%), and medical unit (66.0%). Average age of fallers was 69.1 years and 61.7% of them were older than 71 years. CCI and the patient's department have statistically significant differences in injury or injury levels from falls, but the integrated nursing care services had no significant difference in injury or injury levels from falls. Conclusion: The result of this study can be used as a reference for establishing a fall prevention strategy for hospitalized patients by presenting index values such as the fall rate.

• Safety and Health at Work
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• v.13 no.3
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• pp.343-349
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• 2022

Background: In the United States, the dairy product manufacturing industry has consistently had higher rates of work-related nonfatal injuries and illnesses compared to the national average for industries in all sectors. The selection and implementation of appropriate safety performance indicators are important aspect of reducing risk within safety management systems. This study examined the leading safety indicators implemented in the dairy product-manufacturing sector (NAICS 3115) and their perceived effectiveness in reducing work-related injuries. Methods: Perceptions were collected from individuals with safety responsibilities in the dairy product manufacturing facilities. OSHA Incident Rate (OIR) and Days away, restricted and transferred (DART) rates from 2013 to 2018 were analyzed. Results: The perceived most effective leading were safety observations, stop work authority, near miss reporting, safety audits, preventative maintenance, safety inspections, safety training attendance, and job hazard analysis/safety analysis, respectively. The 6-year trend analysis showed that those implementing all eight top indicators had a slightly lower rates than those that did not implement all eight. Production focused mentality, poor training, and lack of management commitment were perceived as the leading causes of injuries in this industry. Conclusion: Collecting leading indicators with the unique interest to meet the regulatory requirements and to document the management system without the actual goal of using them as input to improve the system most probably will not lead to an effective reduction of negative safety outcomes. For leading indicators to be effective, they should be properly selected, executed, periodically evaluated and actions are taken when necessary.

• Architectural research
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• v.24 no.4
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• pp.105-111
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• 2022

During pandemic period, college students lost lots of such academic opportunities as extra-curriculum social activities, contact classes, and friendly socializing in university campus area, etc. Previous many studies have shown that physical environment has certain relevance on the well-being of human-beings. Recent public statistics on mental health had shown an increase in psychological distress and a decrease in college students and people's well-being during the lockdown in response to the Covid-19 pandemic. However, there were little evidence on what the college students in dormitory suffered from COVID-19 incident in relation with their physical environment. The purpose of this study is to investigate the relationship between environmental factors and psychological well-being of dormitory students in university campus. In order to explore the impact of physical environment on students' psychological well-being, survey instrumentation consisted of 25 indices were employed to measure the level of awareness to each index. A Chi-square analysis on individual characteristics of 200 students found that number of students living in single dwelling unit was statistically significant to maintain their psychological well-being, except for number of students living in each dwelling unit (χ² =128.92, p= .004). Pearson correlation analysis also found that there exists statistically significant relationship between psychological well-being of students and environmental factors. Further, stepwise multiple regression analysis revealed that the most prime predictor for psychological well-being of students residing in dorm was "use of furniture" (β= .281), implying careful design, lay-out and easy-access to interior furniture by facility planner. The study also demonstrated that as the level of positive perception of physical environmental features rose, overall psychological well-being of students also responded positively at specified rate. Finally, the findings reinforce a solid evidence that carefully well-coordinated physical environments play an important role in maintaining emotional stability of college students in dorm even in pandemic period.

• International Journal of Computer Science & Network Security
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• v.23 no.1
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• pp.64-70
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• 2023

Maritime transport is dominant in the overall volume of all international transportation. Existence and overcoming of problems, which cause pressure on shipping safety, remain actual and fully concern both maritime and inland transport. Increasing speed and cargo capacity of the ships along with the reduction of crew members lead to the automation of a growing number of work processes, which indicates the need to actively introduce appropriate measures in the security system of sea-going ships and commercial ports and to develop modern approaches to minimize negative events and incidents in the process of ship operation. Advantages in use of modern methods of monitoring the safety of ship operations, management of possible events and incidents, including investigation of accidents, first, aimed at prevention of negative occurrences and ways of prevention on this basis. Considering statistics on incidents increase, this work presents analysis of general ship accident rate, study of major accidental events growth annually, and investigation of causes of incidents, which most frequently occur in port waters and at open sea. A survey of current approaches to ensuring the safety of shipping by implementing effective tools, such as event and incident management, has been conducted.

• Parasites, Hosts and Diseases
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• v.61 no.1
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• pp.15-23
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• 2023

Concerns about foodborne illnesses caused by Kudoa septempunctata are steadily growing, but reports of K. septempunctata in clinical and food specimens related to food poisoning in Korea are limited. This study aimed to genetically identify K. septempunctata in patients with acute diarrhea and in clinical and food samples related to food poisoning caused by sashimi consumption. Both real-time and nested polymerase chain reaction assays were performed to detect K. septempunctata 18S and 28S rDNA genes in the stools of 348 patients with acute diarrhea, 11 samples (6 stool and 5 rectal swab samples) from patients with food poisoning, and 2 raw Paralichthys olivaceus samples collected from a restaurant where a food poisoning incident occurred. K. septempunctata was identified in 5 clinical specimens (4 stools and 1 rectal swab) and 1 P. olivaceus sashimi sample. All detected K. septempunctata were of genotype ST3. This is the first study to identify K. septempunctata in both patients and food samples with epidemiological relevance in Korea, providing evidence that it is a pathogen that causes food poisoning. Also, this is the first study to confirm the presence of K. septempunctata genes in rectal swabs. Despite continuing suspected occurrences of Kudoa foodborne outbreaks, the rate of identification of K. septempunctata is very low. One reason for this is the limitation in obtaining stool and vomit samples for the diagnosis of Kudoa infection. We strongly suggest the inclusion of rectal swabs among the diagnostic specimens for Kudoa food poisoning.

• Journal of Korean Clinical Nursing Research
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• v.29 no.1
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• pp.56-66
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• 2023

Purpose: This study aimed to investigate whether the comprehensive nursing care service positively affected accidental falls and pressure injuries. Methods: This study was a retrospective study that analyzed the accidental falls and pressure injuries cases in an acute care hospital located in Seoul and compared the rates of accidental falls and pressure injuries before and after the comprehensive nursing care service was operated. Results: Comparing the accidental fall incidence rates per 100 person-months between a comprehensive nursing care ward and a general ward, it showed fewer accidental falls by 0.44 in comprehensive nursing care wards, but the result was not statistically significant. In the case of pressure ulcers, the incident rate per 100 person-month was 6.17 in general wards and 4.77 in comprehensive nursing care wards, which showed that the number of pressure ulcer patients was lower in comprehensive nursing care wards, however it was also not statistically significant. Conclusion: It is not confirmed that the operation of the comprehensive nursing care service contributes to the reduction of accidental hospital falls or pressure injuries. Follow-up studies are recommended to determine the effectiveness of comprehensive nursing services in quality indicators.