• Title/Summary/Keyword: fire effects

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Research trend analysis for Combustion products, Combustion products remove technique (연소생성물제거 기술에 대한 연구 동향 분석)

  • Lee, Hyunjin;Ko, Jae-Wook
    • Journal of the Korean Institute of Gas
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    • v.21 no.1
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    • pp.52-58
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    • 2017
  • According to 2015 ministry of public safety and security statistics, product of combustion makes the most victims while fire. for that reason, recent studies about combustion products have been researched actively in domestic and foreign papers. In domestic, study is handling the combustion product effects on human body and flame propagation. Foreign study is conduct about combustion product effects to shelter in offshore and toxic effects on human. because combustion product is toxic and disturb escape by block the view, many research conducted about optimize combustion product removal facilities using dispersion experiments and CFD simulations. In this study, this paper analysed research trend about toxic gas production model while combustion and its removal facilities, it will be the standard of combustion products research.

Evaluation of the Effect of Burning Rice Paddy Fields on Arthropods in Rice Paddy Fields and Agricultural Fields (논 태우기가 논 포장 및 농경지 서식 절지동물에 미치는 영향 평가)

  • Kong, Minjae;Jeon, Sungwook;Kwon, Kyoung-Hwa;Song, Soon-I;Kim, Kwang-Ho
    • Journal of Environmental Science International
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    • v.30 no.12
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    • pp.993-1003
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    • 2021
  • It is known that the effect of traditional agricultural techniques of burning farmland such as paddy fields and fields gradually declines and affects both the fauna and flora of the rice paddy as well as pests. Therefore, in this study, a study was conducted to investigate the effects of burning rice paddy fields and rice paddy fields levee on the control effect of winter pests inhabiting agricultural land and the amount of pests generated and damaged during the growing season. As a result of this study, the pest control effect of incineration reduces not only the density of pests, but also beneficial insects (natural enemies) and non-reptiles. It is judged that burning has a very low insect control effect. It is expected to be used as basic data to create a sustainable agricultural environment, such as minimizing various negative effects such as pest control effects, wildfires, and air pollution caused by incineration, and suppressing unnecessary incineration and fine dust generation.

A Study on an Adaptive Guidance Plan by Quickest Path Algorithm for Building Evacuations due to Fire (건물 화재시 Quickest Path를 이용한 Adaptive 피난경로 유도방안)

  • Sin, Seong-Il;Seo, Yong-Hui;Lee, Chang-Ju
    • Journal of Korean Society of Transportation
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    • v.25 no.6
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    • pp.197-208
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    • 2007
  • Enormously sized buildings are appearing world-wide with the advancement of construction techniques. Large-scaled and complicated structures will have increased difficulties for dealing with safety, and will demand well-matched safety measures. This research introduced up-to-date techniques and systems which are applied in buildings in foreign nations. Furthermore, it proposed s direct guidance plan for buildings in case of fire. Since it is possible to install wireless sensor networks which detect fires or effects of fire, the plan makes use of this information. Accordingly, the authors completed a direct guidance plan that was based on omnidirectional guidance lights. It is possible to select a route with concern about both time and capacity with a concept of a non-dominated path. Finally, case studies showed that quickest path algorithms were effective for guiding efficient dispersion routes and in case of restriction of certain links in preferred paths due to temperature and smoke, it was possible to avoid relevant links and to restrict demand in the network application. Consequently, the algorithms were able to maximize safety and minimize evacuation time, which were the purposes of this study.

A study on the Improvement Method of the Report and Reward System on an Illegal Behavior of the Emergency Exit (비상구 불법행위 신고포상제도의 개선방안에 관한 연구)

  • Kim, Myeong Sik;Lee, Tae Shik;Cho, Won Cheol
    • Journal of Korean Society of Disaster and Security
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    • v.5 no.2
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    • pp.49-59
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    • 2012
  • The safety management of the emergency exit, by directly related to the $civil^{\circ}$Øs dead in the fire situation, have limited by which the fire station take the on-side and control-centered way of business processing, it is expect to the effects in which the citizen have to concern and to take part. From 2010 years in the back-ground, it is operated nationally the report and reward system on an illegal behavior of the emergency exit, it is happened to the unfit operating situation in the mission and direction of the system up which the exit paparazzi act with intent to receive the reward payments. The study suggests solution through analyzing the illegal emergency exit operation result of sixteen counties and the Seoul metropolitan from year 2010 to 2011. Firstly, the report destination is adjusted to the multiple use establishments and the large-scale multiple use facilities over the limit level is limited under five times the report events of the same people in the minor endorsement. And the fine incomes should be invested to the disaster prevention acting related with the exit. Secondly, for upgrade of the report accuracy, a reporter is received the possible information for the confirmation of an illegal act, has become to lead the pre-monitoring act which the reporter is can to take the safety education and to guide the information about season and vulnerable business location. Finally, considering the support way about the encounter facility, the fire officer is not happen to occur the repetitive report in the same place, is related to the volunteer service system the report acts, consider as the volunteer service time, and must support them to act as the disaster prevention volunteer.

Tracking Propagation Mechanism on the Surface of Polyvinyl-Chloride-Sheathed Flat Cord based on Electric Field Analysis and Gas Discharge Physics (전계해석과 기체방전 이론을 기반으로 한 Polyvinyl-Chloride-Sheathed Flat Cord 표면의 트래킹 진전 메커니즘)

  • Lim, Dong-Young;Park, Herie;Jee, Seung-Wook
    • Fire Science and Engineering
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    • v.33 no.2
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    • pp.30-38
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    • 2019
  • Tracking, which is one of the main causes of electrical fires, is perceived as a physical phenomenon of electrical discharge. Hence tracking should be explained based on electric field analysis, conduction path by electron generation, and gas discharge physics. However, few papers have considered these details. This paper proposes a tracking mechanism including their effects on tracking progress. In order to prove this mechanism, a tracking experiment, an electric field analysis for the carbonization evolution model, and an explanation of the tracking process by gas discharge physics were conducted. From the tracking experiment, the current waveforms were measured at each stage of the tracking progress from corona discharge to tracking breakdown. The electric field analysis was carried out in order to determine the electric field on the surface of a dry-band and the high electric field region for electron generation during the generation and progress of carbonization. In this paper, the proposed tracking mechanism consisted of six stages including electron avalanche by corona discharge, accumulation of positive ions, expansion of electron avalanche, secondary electron emission avalanche, streamer, and tracking by conductive path. The pulse current waveforms measured in the tracking experiment can be explained by the proposed tracking mechanism. The results of this study will be used as the technical data to detect tracking phenomenon, which is the cause of electric fire, and to improve the proof tracking index.

Estimation of Canopy Fuel Characteristics for Pinus densiflora Stands Using Diameter Distribution Models: Forest Managed Stands and Unmanaged Stands (직경분포모형을 이용한 소나무림의 수관연료특성 예측: 산림시업지 임분과 비시업지 임분에서)

  • Lee, Sun Joo;Kim, Sung Yong;Lee, Byung Doo;Lee, Young Jin
    • Journal of Korean Society of Forest Science
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    • v.107 no.4
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    • pp.412-421
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    • 2018
  • The objective of this study was to analyze the effects of forest management activities on canopy fuel characteristics for Pinus densiflora stands in South Korea. We used 1,085 managed stands data and 349 unmanaged stands data of the National Forest Inventory for this study, and it was estimated by using the Weibull function for the growth of stand and canopy fuel characteristics. Comparing the canopy fuel characteristics for the managed stands and unmanaged stands shows that the average canopy fuel load is about 14% higher than that of managed stands, and the canopy bulk density is also approximately 16% higher. The results of comparing growth projections for 40 years, 50 years and 60 years with the Weibull function are as follows: Over time, managed stands was predicted the maximum number of medium and large class diameter, while unmanaged stands was predicted maximum number of small and medium class diameter. From a fire fuel perspective, unmanaged stands are predicted to be of the type small class diameter and high density, which is a good condition for crown fire. In addition, Canopy fuel load, Canopy bulk density is relatively higher than managed stands, indicating that the possibility of high crown fire hazard.

A Study on the Effects of Droplets Characteristics of Water Mist on the Spray Density on the Floor (미분무 액적특성이 살수밀도에 미치는 영향 연구)

  • Kim, Jong-Hoon;Park, Won-Hee;Kim, Woon-Hyung;Myoung, Sang-Yup
    • Journal of the Society of Disaster Information
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    • v.17 no.1
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    • pp.120-127
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    • 2021
  • Purpose: In this study, the effect of changes in the variables related to water droplets on the spray density on the floor in the analysis of the water mist fire protection system using FDS was analyzed. Method: When the spray of the water mist nozzle was analyzed in FDS, Particles Per Seconds, Particle Velocity, Size Distribution, and Spray Pattern Shape that can be set in relation to droplets were input to review the analyzed results. Result: In the analysis results, when the number of particles per second was set above a certain value, the spray density of the floor was similar. In the case of Particle Velocity, as the velocity decreases, the spray density of the central portion increases but decreases at a distance of 0.15m or more. From the analysis of the change in the size distribution function, it was found that an increase in the 𝛾 value increases the spray density of the central part, but the value at a remote location decreases. Compared to the result of applying the Gaussian distribution, the median value decreases dramatically when the uniform distribution is applied, but the value at the adjacent position increases. Conclusion: Variables related to the droplet properties of the FDS affect the spray density of the floor. Therefore, in order to increase the reliability of results before performing analyses such as fire suppression or cooling, a sufficient review of input variables is required.

Effect of Forest Fire on the Microbial Community Activity of Forest Soil according to the Difference between Geology and Soil Depth (산불이 지질과 토심의 차이에 따른 산림토양 미생물 군집 활성도에 미치는 영향에 대한 연구)

  • Ji Seul Kim;Jun Ho Kim;Hyeong Chul Jeong;Eun Young Lee
    • The Journal of Engineering Geology
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    • v.33 no.1
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    • pp.15-25
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    • 2023
  • The effects of forest fires on the activity of microbial communities in topsoil and subsoil were investigated. Samples were collected from Korean forest soils comprising mainly igneous and sedimentary rocks. Analysis of beta-glucosidase, found higher microbial activity in sedimentary rocks than in igneous rocks. Enzyme activity was not observed immediately after fire, but was restored over time. The enzyme activity of subsoil was inhibited by 33~46% compared with that in the topsoil, regardless of soil damage. The effect of fire on the availability of microbial substrate was investigated using EcoPlate. The percentages of average well color development values of damaged and normal topsoil were 52.7~56.8% and 62.3~83.6%, respectively. Forest fires appear to affect the diversity and substrate availability of the subsoil microbial community by accelerating the decomposition of soil organic matter. The Shanon index, representing microbial biodiversity, was high in the topsoil of all samples; it was higher for soil microorganisms in sedimentary rocks than in igneous rocks, and higher in topsoil than in subsoil.

A Study on Method to Activate the Operation of a Fire Safety Experience Center Based on Virtual Reality (가상현실 기반 소방안전체험관 운영 활성화 방안 연구)

  • Young Sook Kim;Kwangsu Moon
    • Journal of the Society of Disaster Information
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    • v.18 no.4
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    • pp.713-728
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    • 2022
  • Purpose: This study examined the effect of VR safety education content quality on behavioral intention and collect operational opinions through interview. Method: Based on the survey data of 93 former and current officers, the hypothesis was verified. In addition, 15 fire safety experience centers were visited to conduct interview. Result: For the quality of VR safety education contents, immersion and convenience had a significant effect on usage satisfaction, recommendation intention, and field application intention. In addition, convenience and aesthetic experience had a significant effect on the educational effect, but immersion and diversity did not significant. In the interview, they suggested that VR education has high user satisfaction and good educational effects. The quality of content(particularly immersion and convenience) is an important factor in VR education. In the long-term persepective, it is necessary to prepare a standard teaching plan for each disaster, in addition, manpower, expertise, maintenance problems, and etc. Conclusion: Through these results, it was confirmed that VR experience content quality affects behavioral intention and educational effect and that efforts and investments to improve content quality are needed to enhance the effectiveness of VR experience education. And the contents derived from the interview will be helpful in the operation of an effective fire safety experience center.

Growth and Nutrient Dynamics of Planted Tree Species Following Fertilization in a Fire-Disturbed Urban Forest (도시 숲 산불피해지의 시비에 따른 식재 수목의 생장 및 양분 동태)

  • Choonsig Kim;Gyeongwon Baek
    • Journal of Korean Society of Forest Science
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    • v.113 no.2
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    • pp.143-152
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    • 2024
  • This study was conducted to evaluate the growth and nutrient dynamics in response to fertilization of four tree species (LT: Liriodendron tulipifera L.; PY: Prunus yedoensis Matsumura; QA: Quercus acutissima Ca rruth; a nd PT: Pinus thunbergii Parl.) planted in a fire-disturbed urban forest in Bongdaesan (Mt.), Ulsan Metropolitan Area, South Korea. The trees were planted in 2009, and compound fertilizers (N6P4K1) were applied in April 2013 and March 2014. Tree growth, soil, and foliage nutrients were examined from March 2013 to October 2016. The regression coefficients for the increment of the diameter at breast height (DBH) significantly differed between the fertilized and unfertilized plots, suggesting the significant effects of fertilization. By contrast, fertilization did not affect the coefficients for height increments. Regarding soil nutrient contents, organic carbon and total nitrogen concentrations were lower in the fertilized plots than in the unfertilized plots, whereas available phosphorus, exchangeable calcium, and magnesium concentrations were higher in the fertilized plots than in the unfertilized plots. In foliage, nitrogen and phosphorus concentrations were higher in the fertilized plots than in the unfertilized plots, whereas potassium, calcium, and magnesium concentrations were not affected by fertilization. Nutrient concentration of foliage among the tree species were higher in LT and PY than in QA and PT. These results suggest that fertilizers may be used to enhance soil fertility and the growth and nutrient status of tree species planted in a fire-disturbed urban forest.