• Title/Summary/Keyword: impact damage

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Analysis of the Impact of Transmission Towers on the Performance of RF Scanners for Drone Detection (드론탐지용 RF스캐너의 성능에 송전탑이 미치는 영향 분석)

  • Moon-Hee Lee;Jeong-Ju Bang
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.23 no.1
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    • pp.112-122
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    • 2024
  • Recently, as unmanned aerial vehicle technology such as drones has developed, there are many environmental, social and economic benefits, but if there is malicious intent against important national facilities such as airports, public institutions, power plants, and the military, it can seriously affect national safety and people's lives. It can cause damage. To respond to these drone threats, attempts are being made to introduce detection equipment such as RF scanners. In particular, power transmission towers installed in substations, power plants, and Korea's power system can affect detection performance if the transmission tower is located in the RF scanner detection path. In the experiment, a commercial drone was used to measure the signal intensity emitted from the drone and confirm the attenuation rate. The average and maximum attenuation rates showed similar trends in the 2.4 GHz and 5.8 GHz bands, and were also affected by the density of the structure.

Research on Improving the Performance of YOLO-Based Object Detection Models for Smoke and Flames from Different Materials (다양한 재료에서 발생되는 연기 및 불꽃에 대한 YOLO 기반 객체 탐지 모델 성능 개선에 관한 연구 )

  • Heejun Kwon;Bohee Lee;Haiyoung Jung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.37 no.3
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    • pp.261-273
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    • 2024
  • This paper is an experimental study on the improvement of smoke and flame detection from different materials with YOLO. For the study, images of fires occurring in various materials were collected through an open dataset, and experiments were conducted by changing the main factors affecting the performance of the fire object detection model, such as the bounding box, polygon, and data augmentation of the collected image open dataset during data preprocessing. To evaluate the model performance, we calculated the values of precision, recall, F1Score, mAP, and FPS for each condition, and compared the performance of each model based on these values. We also analyzed the changes in model performance due to the data preprocessing method to derive the conditions that have the greatest impact on improving the performance of the fire object detection model. The experimental results showed that for the fire object detection model using the YOLOv5s6.0 model, data augmentation that can change the color of the flame, such as saturation, brightness, and exposure, is most effective in improving the performance of the fire object detection model. The real-time fire object detection model developed in this study can be applied to equipment such as existing CCTV, and it is believed that it can contribute to minimizing fire damage by enabling early detection of fires occurring in various materials.

Development and Implementation of a Low-noise and Safe Dismantling Method for Full-Span Aluminum Slab Formwork Supported by Filler Supports (필러겸용 스포터로 지지되는 전구간 알루미늄 슬래브 거푸집의 저소음 안전낙하 공법개발 및 적용연구)

  • Lim, Nam-Gi
    • Journal of the Korea Institute of Building Construction
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    • v.24 no.2
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    • pp.261-271
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    • 2024
  • The widespread adoption of aluminum slab formwork in modern construction, evident in both domestic and international projects, offers numerous advantages. However, a critical challenge persists regarding the dismantling process for these slabs. The current industry standard involves dropping the slabs to the ground floor upon removal. This practice raises several concerns, notably the generation of significant noise pollution that disrupts nearby communities. More importantly, the risk of worker injuries due to falls from height during the dismantling process is a serious safety hazard. Additionally, the impact from dropping the slabs can damage the aluminum itself, leading to increased replacement costs. These drawbacks necessitate the exploration of alternative dismantling techniques that prioritize worker safety, material sustainability, and overall process efficiency. Accordingly, in this study, when the entire first-generation slab formwork of an apartment house is simultaneously lowered to a reachable position for workers, it is then disassembled and lifted for transport to the next floor. This approach has the potential to demonstrate improvements in safety, quality, economy, and process efficiency.

Optimization of Ascorbic Acid Encapsulation in PLA Microcapsules Using Double Emulsion Process (이중유화법을 이용한 PLA 마이크로캡슐 내부로의 아스코르브산 캡슐화 공정 최적화)

  • Ji Won Yun;Young Mi Chung
    • Applied Chemistry for Engineering
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    • v.35 no.2
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    • pp.115-121
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    • 2024
  • This study analyzed the influence of process variables affecting the thermodynamic equilibrium and fluid dynamics of interfaces such as reverse micelle, salt concentration, interfacial tension, and viscosity of fluids to optimize the microencapsulation process using the W1/O/W2 double emulsion method. The process variable with the greatest impact on encapsulation efficiency was found to be the difference in osmotic pressure between the W1 and W2 phases. It was observed that increasing the salt concentration in the W2 phase or decreasing the ascorbic acid concentration in the W1 phase resulted in higher encapsulation efficiency. Additionally, a larger difference in osmotic pressure led to increased damage to the surface of the microparticles, as confirmed by SEM images. The introduction of reverse micelles, which was anticipated to increase encapsulation efficiency, either had a low contribution or even decreased encapsulation efficiency. The yield of microcapsules was expressed as a universal function, applicable to all process conditions or solution compositions. According to this universal function, no further increase in yield was observed beyond the Ca (capillary number) of approximately 20.

Preclinical Evidence and Underlying Mechanisms of Polygonum multiflorum and Its Chemical Constituents Against Cognitive Impairments and Alzheimer's Disease

  • Jihyun Cha;Ji Hwan Yun;Ji Hye Choi;Jae Ho Lee;Byung Tae Choi;Hwa Kyoung Shin
    • Journal of Pharmacopuncture
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    • v.27 no.2
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    • pp.70-81
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    • 2024
  • Objectives: Cognitive impairments, ranging from mild to severe, adversely affect daily functioning, quality of life, and work capacity. Despite significant efforts in the past decade, more than 200 promising drug candidates have failed in clinical trials. Herbal remedies are gaining interest as potential treatments for dementia due to their long history and safety, making them valuable for drug development. This review aimed to examine the mechanisms behind the effect of Polygonum multiflorum on cognitive function. Methods: This study focused primarily on the effects of Polygonum multiflorum and its chemical constituents on cognitive behavioral outcomes including the Morris water maze, the passive avoidance test, and the Y maze, as well as pathogenic targets of cognitive impairment and Alzheimer's disease (AD) like amyloid deposition, amyloid precursor protein, tau hyperphosphorylation, and cognitive decline. Additionally, a thorough evaluation of the mechanisms behind Polygonum multiflorum's impact on cognitive function was conducted. We reviewed the most recent data from preclinical research done on experimental models, particularly looking at Polygonum multiflorum's effects on cognitive decline and AD. Results: According to recent research, Poligonum multiflorum and its bioactive components, stilbene, and emodin, influence cognitive behavioral results and regulate the pathological target of cognitive impairment and AD. Their mechanisms of action include reducing oxidative and mitochondrial damage, regulating neuroinflammation, halting apoptosis, and promoting increased neurogenesis and synaptogenesis. Conclusion: This review serves as a comprehensive compilation of current experiments on AD and other cognitive impairment models related to the therapeutic effects of Polygonum multiflorum. We believe that these findings can serve as a basis for future clinical trials and have potential applications in the treatment of human neurological disorders.

LncRNA AC005332.7 Inhibited Ferroptosis to Alleviate Acute Myocardial Infarction Through Regulating miR-331-3p/CCND2 Axis

  • Rixin Dai;Xiheng Yang;Wujin He;Qiang Su;Xuexin Deng;Juanfen Li
    • Korean Circulation Journal
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    • v.53 no.3
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    • pp.151-167
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    • 2023
  • Background and Objectives: Acute myocardial infarction (AMI) often occurs suddenly and leads to fatal consequences. Ferroptosis is closely related to the progression of AMI. However, the specific mechanism of ferroptosis in AMI remains unclear. Methods: We constructed a cell model of AMI using AC16 cells under oxygen and glucose deprivation (OGD) conditions and a mice model of AMI using the left anterior descending (LAD) ligation. The 3-(4, 5-dimethylthiazol-2-yl)-2, 5 diphenyltetrazolium bromide was employed to determine cell viability. The levels of lactate dehydrogenase, creatine kinase, reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and iron were measured using corresponding kits. Dual luciferase reporter gene assay, RNA-binding protein immunoprecipitation, and RNA pull-down were performed to validate the correlations among AC005332.7, miR-331-3p, and cyclin D2 (CCND2). Hematoxylin and eosin staining was employed to evaluate myocardial damage. Results: AC005332.7 and CCND2 were lowly expressed, while miR-331-3p was highly expressed in vivo and in vitro models of AMI. AC005332.7 sufficiency reduced ROS, MDA, iron, and ACSL4 while boosting the GSH and GPX4, indicating that AC005332.7 sufficiency impeded ferroptosis to improve cardiomyocyte injury in AMI. Mechanistically, AC005332.7 interacted with miR-331-3p, and miR-331-3p targeted CCND2. Additionally, miR-331-3p overexpression or CCND2 depletion abolished the suppressive impact of AC005332.7 on ferroptosis in OGD-induced AC16 cells. Moreover, AC005332.7 overexpression suppressed ferroptosis in mice models of AMI. Conclusions: AC005332.7 suppressed ferroptosis in OGD-induced AC16 cells and LAD ligation-operated mice through modulating miR-331-3p/CCND2 axis, thereby mitigating the cardiomyocyte injury in AMI, which proposed novel targets for AMI treatment.

A Study on the Establishment of Disaster Prevention Plans for Nuclear Facilities considering Complex Disasters (복합재난을 고려한 원자력시설 사고대비 방재계획 수립방안)

  • Jihoon Shin;Younwon Park;Seunghyeon Kim;Minho Cha;Minsang Ryu
    • Journal of Korean Society of Disaster and Security
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    • v.16 no.4
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    • pp.85-99
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    • 2023
  • By the social advancement, radiological disaster prevention planning is getting important considering complex disasters as in the Fukushima radiological disaster occurred by a chain of natural disasters. However, it has yet to be suggested the specific prevention plans for the complex disasters in the field of national radiological disaster prevention. This study aims to analyze the types of complex disasters in order to select the ones that are relatively more likely to occur in the domestic environment. It is also to analyze the impact on the radiological disaster prevention by searching damage spread of the classified natural disasters. We provides the necessary criterial for establishing disaster prevention plans through the scenarios for radiological emergency responses based on complex disasters. it is thought that these criteria can help prepare for the worst case scenario and implement effective resident protection.

Analysis of University Cafeteria Safety Based on Pathfinder Simulation

  • Zechen Zhang;Jaewook Lee;Hasung Kong
    • International Journal of Internet, Broadcasting and Communication
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    • v.16 no.2
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    • pp.209-217
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    • 2024
  • Recent years have seen a notable increase in fire incidents in university cafeterias, yet the social attention to these occurrences remains limited. Despite quick responses to these incidents preventing loss of life, the need for large-scale evacuation in such high foot traffic areas can cause significant disruptions, economic losses, and panic among students. The potential for stampedes and unpredictable damage during inadequate evacuations underscores the importance of fire safety and evacuation research in these settings. Previous studies have explored evacuation models in various university environments, emphasizing the influence of environmental conditions, personal characteristics, and behavioral patterns on evacuation efficiency. However, research specifically focusing on university cafeterias is scarce. This paper addresses this gap by employing Pathfinder software to analyze fire spread and evacuation safety in a university cafeteria. Pathfinder, an advanced emergency evacuation assessment system, offers realistic 3D simulations, crucial for intuitive and scientific evacuation analysis. The studied cafeteria, encompassing three floors and various functional areas, often exceeds a capacity of 1500 people, primarily students, during peak times. The study includes constructing a model of the cafeteria in Pathfinder and analyzing evacuation scenarios under different fire outbreak conditions on each floor. The paper sets standard safe evacuation criteria (ASET > RSET) and formulates three distinct evacuation scenarios, considering different fire outbreak locations and initial evacuation times on each floor. The simulation results reveal the impact of the fire's location and the evacuation preparation time on the overall evacuation process, highlighting that fires on higher floors or longer evacuation preparation times tend to reduce overall evacuation time.In conclusion, the study emphasizes a multifaceted approach to improve evacuation safety and efficiency in educational settings. Recommendations include expanding staircase widths, optimizing evacuation routes, conducting regular drills, strengthening command during evacuations, and upgrading emergency facilities. The use of information and communication technology for managing emergencies is also suggested. These measures collectively form a comprehensive framework for ensuring safety in educational institutions during fire emergencies.

A case of syncope in a villager with hypertrophic cardiomyopathy after hydrogen sulfide exposure by an unauthorized discharge of wastewater

  • Hyeonjun Kim;Seunghyeon Cho;Inho Jung;Sunjin Jung;Won-Ju Park
    • Annals of Occupational and Environmental Medicine
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    • v.35
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    • pp.34.1-34.8
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    • 2023
  • Background: Hydrogen sulfide is a toxic substance that humans can be exposed to occupationally, and cases of hydrogen sulfide poisoning of workers in industrial sites are commonly reported. However, there have been no cases of poisoning of the public due to an unauthorized discharge of wastewater, so it is important to describe this incident. Case presentation: In a small village in Jeollanam-do, Republic of Korea, accounts of a terrible stench had been reported. A 26-year-old man who lived and worked in a foul-smelling area was taken to the emergency room with a headache, dizziness, nausea, and repeated syncope. A subsequent police and Ministry of Environment investigation determined that the cause of the stench was the unauthorized discharge of 9 tons of wastewater containing hydrogen sulfide through a stormwater pipe while the villagers were sleeping. The patient had no previous medical history or experience of symptoms. Leukocytes and cardiac markers were elevated, an electrocardiogram indicated biatrial enlargement, left ventricular hypertrophy, and corrected QT interval prolongation. Myocardial hypertrophy was detected on a chest computed tomography scan, and hypertrophic cardiomyopathy was confirmed on echocardiography. After hospitalization, cardiac marker concentrations declined, symptoms improved, and the patient was discharged after 7 days of hospitalization. There was no recurrence of symptoms after discharge. Conclusions: We suspect that previously unrecognized heart disease manifested or was aggravated in this patient due to exposure to hydrogen sulfide. Attention should be paid to the possibility of unauthorized discharge of hydrogen sulfide, etc., in occasional local incidents and damage to public health. In the event of such an accident, it is necessary to have government guidelines in place to investigate health impact and follow-up clinical management of exposed residents.

Classification Abnormal temperatures based on Meteorological Environment using Random forests (랜덤포레스트를 이용한 기상 환경에 따른 이상기온 분류)

  • Youn Su Kim;Kwang Yoon Song;In Hong Chang
    • Journal of Integrative Natural Science
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    • v.17 no.1
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    • pp.1-12
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    • 2024
  • Many abnormal climate events are occurring around the world. The cause of abnormal climate is related to temperature. Factors that affect temperature include excessive emissions of carbon and greenhouse gases from a global perspective, and air circulation from a local perspective. Due to the air circulation, many abnormal climate phenomena such as abnormally high temperature and abnormally low temperature are occurring in certain areas, which can cause very serious human damage. Therefore, the problem of abnormal temperature should not be approached only as a case of climate change, but should be studied as a new category of climate crisis. In this study, we proposed a model for the classification of abnormal temperature using random forests based on various meteorological data such as longitudinal observations, yellow dust, ultraviolet radiation from 2018 to 2022 for each region in Korea. Here, the meteorological data had an imbalance problem, so the imbalance problem was solved by oversampling. As a result, we found that the variables affecting abnormal temperature are different in different regions. In particular, the central and southern regions are influenced by high pressure (Mainland China, Siberian high pressure, and North Pacific high pressure) due to their regional characteristics, so pressure-related variables had a significant impact on the classification of abnormal temperature. This suggests that a regional approach can be taken to predict abnormal temperatures from the surrounding meteorological environment. In addition, in the event of an abnormal temperature, it seems that it is possible to take preventive measures in advance according to regional characteristics.