• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.22-28
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• 2021

This is a basic study on the development of deep learning-based algorithms to detect smoke before the smoke detector operates in the event of a ship fire, analyze and utilize the detected data, and support fire suppression and evacuation activities by predicting the spread of smoke before it spreads to remote areas. Proposed algorithms were reviewed in accordance with the following procedures. As a first step, smoke images obtained through fire simulation were applied to the YOLO (You Only Look Once) model, which is a deep learning-based object detection algorithm. The mean average precision (mAP) of the trained YOLO model was measured to be 98.71%, and smoke was detected at a processing speed of 9 frames per second (FPS). The second step was to estimate the spread of smoke using the coordinates of the boundary box, from which was utilized to extract the smoke geometry from YOLO. This smoke geometry was then applied to the time series prediction algorithm, long short-term memory (LSTM). As a result, smoke spread data obtained from the coordinates of the boundary box between the estimated fire occurrence and 30 s were entered into the LSTM learning model to predict smoke spread data from 31 s to 90 s in the smoke image of a fast fire obtained from fire simulation. The average square root error between the estimated spread of smoke and its predicted value was 2.74.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.193-200
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• 2022

We conducted a case study to determine the optimal model parameters and predictors of Long Short-Term Memory (LSTM) for the reproduction of dissolved oxygen (DO) concentration in Jinhae Bay. The model parameter case study indicated the lowest accuracy when the Hidden node=10, Epoch=100. This was caused by underfitting of machine learning. The accuracy increased as the Hidden node and Epoch increased. The accuracy was the highest when the Hidden node=80 and Epoch=100 with R²=0.99. In the bottom DO reproduction of Step 1 of the predictors case study, accuracy was highest when the water temperature was used as a predictor with R²=0.81. In Step 2, The R² value increased up to 0.92 when the water temperature and SiO₂ were used as a predictor. This was caused by a high correlation between the bottom DO and SiO₂ concentrations. Consequently, we determined the optimal model parameters and predictors of LSTM for the reproduction of DO concentration in Jinhae Bay.

• Korean Journal of Applied Biomechanics
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• v.14 no.3
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• pp.67-82
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• 2004

The purpose of this study was to evaluate the function and the safety of an additional weight shoe developed for the improvement of aerobic capacity, and to improve some problems found by subject's test for an additional weight shoe. The subjects employed for this study were 10 college students. 4 video cameras, AMTI force platform and Pedar insole pressure distribution measurement device were used to analyze foot motions. The results of the study were as follows: 1 The initial achilles tendon angle and initial rearfoot pronation angle of an additional weight shoe during walking were 183.7 deg and 2.33 deg, respectively, and smaller than a barefoot condition. Maximum achilles tendon angle and the angular displacement of achilles tendon angle were 185.35 deg and 4.21 deg respectively, and smaller than barefoot condition. Thus rearfoot stability variables were within the permission value for safety. 2. Maximal anterior posterior ground reaction force of additional weight shoe was appeared to be 1.01-1.2 B.W., and was bigger than a barefoot condition. The time to MAPGRF of an additional weight shoe was longer than a barefoot condition. Maximal vertical ground reaction force of additional weight shoe was appeared to be 2.3-2.7 B.W., and was bigger than a barefoot condition in propulsive force region. But A barefoot condition was bigger in braking force region. The time to MVGRF of an additional weight shoe was longer than a barefoot condition. 3. Regional peak pressure was bigger in medial region than in lateral region in contrast to conventional running shoes. The instant of regional peak pressure was M1-M2-M7-M4-M6-M5 -M3, and differed form conventional running shoes. Regional Impulse was shown to be abnormal patterns. There were no evidences that an additional weight shoe would have function and safety problems through the analysis of rearfoot control and ground reaction force during walking. However, There appeared to have small problem in pressure distribution. It was considered that it would be possible to redesign the inner geometry. This study could not find out safety on human body and exercise effects because of short term research period. Therefore long term study on subject's test would be necessary in the future study.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.130-138
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• 2015

According to the "Safety Evaluation Detailed Instructions (Dam)", a precise safety inspection is carried out for dams that exceed a certain scale. However, as the Hydrological Safety Evaluation from various evaluation standards is designed to evaluate the safety of existing dams considering PMF(Probable Maximum Flood), the evaluation is much less applicable for most agricultural reservoirs. Therefore, the Hydrological Safety Guidelines for agricultural reservoirs are expected to be re-evaluated considering the diverse risk factors with the coefficient model and AHP(Analytic Hierarchy Process) in this study. The coefficient model has been developed by selecting the hydrological safety superordinate subordinate evaluation factors to reflect diverse risk factors of agricultural reservoirs. This study indicated that in the short term, improving the safety check condition evaluation grade will be useful to improve the hydrological safety of the agricultural reservoir because it can be performed immediately.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.315-322
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• 2013

Objectives: This study was conducted in order to prepare fundamental data and assess the short-term effects of applying cerebrovascular disease prevention programs by the Ministry of Employment and Labor and the Korea Occupational Safety and Health Agency (KOSHA) in Korea. Methods: The number of study subjects was 2,676 workers (58.5%) who were able to evaluate the level of incidence risk at pre- and post-applications of the program, among the 4,576 total workers who were enrolled in the cerebrovascular disease prevention program during 2011. The guidelines for this prevention program were adopted from KOSHA GUIDE H-1-2010. To determine the program' effectiveness, the workers'risks for cerebrovascular disease were assessed pre- and post-application of the program. Results: The blood pressure level was significantly reduced by 4.09 mmHg for the mean systolic blood pressures and 5.47 mmHg for diastolic blood pressures, respectively. The mean level of total cholesterol and BMI were also reduced significantly by 2.07 g/dl and 0.1 $0.1kg/m^2$. The rate of smoking was decreased by 4.0% and the percentage of workers engaging in regular exercise was increased by 29.8%. The level of overall cerebrovascular disease risk was reduced among 1,451 (70.7%) of 2,052 workers at low risk and above. The level of cerebrovascular disease risk was lower in the improved group for health behavior than the unimproved group (odds ratio =1.7, p < 0.001). Conclusions: The author considers that the application of the cerebrovascular disease prevention program by the Korea Occupational Safety and Health Agency reduced cerebrovascular diseases risks among workers who were enrolled in the cerebrovascular disease prevention program and it must be accompanied by an improvement in health behavior for prevention of cerebrovascular disease.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4993-4996
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• 2015

Background: To evaluate the efficacy and safety of albumin-bound paclitaxel-based chemotherapy in treatment for patients with advanced esophageal cancer who failed in first-line chemotherapy. Materials and Methods: We collected29 advanced esophageal cancer patients who received albumin-bound paclitaxel-based chemotherapy fromJune 2009 to September 2013, and the efficacy and safety of the compound were evaluated. These patients were treated with $100-150mg/m^2$ nab-paclitaxel on days 1,8. The cycle was repeated every 3 weeks. Clinical efficacy was evaluated every two cycles. Results: Of the 29 patients, two persons interrupted treatment because of adverse reactions, failed to evaluate efficacy effect. The rest of 27 patients who could be evaluated for short-term response, 10 patients (37%) achieved partial response, 2 (7.4%) remained stable disease, and 15 (55.6%) had progressivedisease. The objective response rate was 37%, and the disease control rate was 44.4%.The median time to progression was 6.6 months.The major adverse reactions includedalopecia (62.07%), neutropenia (65.5%), gastrointestinalreaction (10.3%) andsensory neuropathy(6.8%). Conclusions: The albumin-bound paclitaxel-based chemotherapy is efficacy and safety in treatment for patients with advanced esophageal cancer who failed in first-line chemotherapy.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.167-172
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• 2010

CANDU spent fuel is to be disposed of at repository finally rather than recycled because of its low fissile nuclide concentration. But the difficult situation of finding a repository site can not help introducing a interim storage in the short term. It is required to find an optimum timing of geological disposal of CANDU spent fuels related to the interim storage operation period. The major factors for determining the disposal starting time are considered as safety, economics, and public acceptance. Safety factor is compared in terms of the decay heat and non-proliferation. Economics factor is compared from the point of the operation cost, and public acceptance factor is reviewed from the point of retrievability and inter-generation ethics. This paper recommended the best solution for the disposal starting time by analyzing the above factors. It is concluded that the optimum timing for the CANDU spent fuel disposal is around 2041 and that the sooner disposal time, the better from the point of technical and safety aspects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.530-535
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• 2005

A Korean traditional herbal formular, Taeumbiman-tang(TBT), was based on Taeumjowi-tang, currently the most widely used herbal formula compound, and which is known to be safe and have a positive effect on adult obesity. TBT was given to obese children for thirty days, and was found to be clinically safe and effective. The subjects were children who had been admitted into the hospital to be treated for obesity, that had more than 20% relative body weight. Originally there were 19 subjects, but 5 dropped out of the experiment. There were 5 girls and 9 boys, whose average ages were $11.00\;{\pm}\;2.60$ years, average weight was $54.01\;{\pm}\;18.59\;kg$. As a pretest, all of the volunteers were examined for height, weight, blood pressure, pulse rate, EKG, and chest radiography. The subjects underwent interview, body measurement tests, blood tests, and safety tests under 8 hour fasting state. After 15 days of TBT intake, the safety tests and the interview were conducted. The interview, body measurement tests, blood tests, and safety tests were conducted again after the 30 day trial was completed. The short term effects of TBT on obese children is weight loss. It did not cause any significant changes in the subject's livers, hearts, and kidneys, and clinically dangerous side effects or withdrawal symptoms were not observed.

• Journal of the Korean Society of Safety
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• v.34 no.2
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• pp.56-62
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• 2019

Secondary accident is common type of accident which occurs in Korean highway tunnels. Fatality rate of secondary accidents in highway tunnels is six time higher than primary accidents. Video type VMS is a new way of providing information to road users which was recently introduced by Korean government to prevent secondary accidents in highway tunnels. In this study we compared changes in driver's behavior when information is provided by Text type and Video Type VMS. In addition to analyze effects of secondary accident reduction, driving behavior was analyzed based on providing advance information by video type VMS at tunnel entrance. Analysis showed that both text type and video type VMS has similar effect on driver behavior. Video type VMS showed positive effect on driver's behavior to prevent secondary accident when information is provided 1km ahead of accident. Considering there results and the short-term memory characteristics of driver, it was determined that information should be provide at about 650m from the entrance of the tunnel. The results of this study are consistent with the requirement that VMS should be installed at least 500m ahead of tunnel and produce more accurate providing information points. 650m is also appropriate interval for providing information in tunnel to cope with an accident ahead.

• Safety and Health at Work
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• v.14 no.3
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• pp.303-308
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• 2023

Background: Occupational workers at altitudes are more prone to falls, leading to catastrophic outcomes. Acrophobia, height-related anxiety, and affected executive functions lead to postural instabilities, causing falls. This study investigated the effects of repeated virtual height exposure and training on cognitive processing and height-related anxiety. Methods: Twenty-eight healthy volunteers (age 20.48 ± 1.26 years; mass 69.52 ± 13.78 kg) were recruited and tested in seven virtual environments (VE) [ground (G), 2-story altitude (A1), 2-story edge (E1), 4-story altitude (A2), 4-story edge (E2), 6-story altitude (A3), and 6-story edge (E3)] over three days. At each VE, participants identified occupational hazards present in the VE and completed an Attitude Towards Heights Questionnaire (ATHQ) and a modified State-Trait Anxiety Inventory Questionnaire (mSTAIQ). The number of hazards identified and the ATHQ and mSTAIQ scores were analyzed using a 7 (VE; G, A1, A2, A3, E1, E2, E3) x 3 (DAY; DAY 1, DAY 2, DAY 3) factorial repeated measures analysis of variance. Results: The participants identified the lowest number of hazards at A3 and E3 VEs and on DAY 1 compared to other VEs and DAYs. ATHQ scores were lowest at G, A1, and E1 VEs. Conclusion: Cognitive processing is negatively affected by virtual altitudes, while it improves with short-term training. The features of virtual reality, such as higher involvement, engagement, and reliability, make it a better training tool to be considered in ergonomic settings. The findings of this study will provide insights into cognitive dual-tasking at altitude and its challenges, which will aid in minimizing occupational falls.