• Title/Summary/Keyword: fire occurrence factor

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Spalling Properties of High Strength RC Column in accordance with Various W/B and Fiber Types (물결합재비 및 섬유종류 변화에 따른 고강도 모의 구조체의 폭렬특성)

  • Han, Cheon-Goo;Kim, Seoung-Soo;Kim, Sang-Shik;Jee, Suk-Won;Oh, Won-Young;Song, Yong-Won
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.11a
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    • pp.83-86
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    • 2007
  • This study provides the practical application of the concrete using fiber to protect from fire studied by previous research. The fluidity and air content is satisfied with the targets, and the compressive strength is over 60MPa on W/B 35% and 80MPa on W/B 20 and 25%. For the properties of the spalling after the fire test, there is no spalling or slight occurrence on the specimens. However, for the RC column, the covering concrete fall off caused by spalling occurrence. Based on the results, it is thought that the fiber content should be put into the safety factor to prevent spalling for the structures.

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Characteristics of Surface Flow on the Forest Fire Sites by Using Rainfall Simulator (인공강우장치를 이용한 산불발생지의 지표유출 특성에 관한 연구)

  • Lee, Heon Ho;Joo, Jae duk
    • Journal of Korean Society of Forest Science
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    • v.95 no.3
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    • pp.350-357
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    • 2006
  • For the purpose of this study, the characteristics of surface flow through the survey of rainfall intensity and degree of slope on fire sites by using rainfall simulator was examined and analysed. And also the relationship between the amount of surface flow and rainfall intensity, degree of slope and elapsed year after forest fire occurrence influencing on the surface flow were analysed. The results obtained were as follows: 1. The amount of surface flow by year of occurrence of forest fire was increased 2,2 to 3,2 times as rainfall intensity was increased by 30 mm/hr, and 1.5 to 1.9 times as degree of slope was increased by $10^{\circ}$, 2, Even though ground vegetation in forest fire sites was recovered more than 80%, the amount of surface flow in initial rainfall was relatively much and it seemed that vegetation didn't play substantial roles in reducing runoff. 3, The amount of surface flow by rainfall intensity and degree of slope in accordance with elapsed years after forest fire was reduced 22,3% to 41,8% in three years after fire as compared to the first year of fire occurrence. The amount of surface flow were significantly differentiated by rainfall intensity and degree of slope in the first year of fire occurrence and the difference were gradually reduced afterwards. 4. In the analysis on influences of each factors on the amount of surface flow on forest fire sites, the amount of surface flow was significant differences in major impacts of each rainfall intensity, degree of slope and elapsed year after fire and interaction of rainfall intensity ${\times}$ degree of slope and rainfall intensity ${\times}$ elapsed year after fire, but no differences were observed in interaction of degree of slope ${\times}$ elapsed year after tire and rainfall intensity ${\times}$ degree of slope ${\times}$ elapsed year after tire. Rainfall intensity was the most affecting factor on the amount of surface flow and followed by degree of slope and elapsed year after fire.

A Study on the Disaster Prevention of the Royal Tomb Eureung in the Mountain Cheonjang - Estimation on Forest Fire Risk Considering Forest Type and Topography - (천장산 의릉의 방재대책에 관한 연구 - 임상과 지형인자를 고려한 산불위험성 평가 -)

  • Won, Myoung-Soo;Lee, Woo-Kyun;Choi, Jong-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.1
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    • pp.59-65
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    • 2010
  • The purpose of this study is to analyze the risk of the forest fire, considering the topography and the forest, for establishing disaster prevention measures of cultural heritage, Uireung, over in Cheonjang-mountain. To do that, we estimate the occurrence and spread of the forest fire over in Cheonjang-mountain through a forest fire probability model(logistic regression), using the space characteristic data($100m{\times}100m$). The factor, occurrence of the forest fire, are diameter class, southeast, southwest, south, coniferous, deciduous, and mixed forest. We assume the probability of the fire forest in each point as follow : [1+exp{-(-4.8081-(0.02453*diameter class)+(0.6608*southeast)+(0.507*southwest)+(0.7943*south)+(0.29498*coniferous forest)+(0.28897*deciduous forest)+(0.17788*mixed forest))}]$^{-1}$. To divide dangerous zone of the big forest fire, we make the basic materials for disaster prevention measures, through the map of coniferous forests, deciduous forests, and mixed forest. The damage of cultural heritage caused by a forest fire will be reduced through the effective preventive measures, by forecast a forest fire to using this study.

The Studies on Relationship Between Forest Fire Characteristics and Weather Phase in Jeollanam-do Region (통계자료에 의한 기상과 산불특성의 관련성 -전라남도지방을 중심으로-)

  • Lee, Si-Young;Park, Houng-Sek;Kim, Young-Woong;Yun, Hoa-Young;Kim, Jong-Kab
    • Journal of agriculture & life science
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    • v.45 no.4
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    • pp.29-35
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    • 2011
  • A forest fire was one of the huge disasters and damaged human lifes and a properties. Therefore, many countries operated forest fire forecasting systems which developed from forest fire records, weather data, fuel models and etc. And many countries also estimated future state of forest fire using a long-term climate forecasting like GCMs and prepared resources for future huge disasters. In this study, we analyzed relationships between forest fire occurrence and meteorological factors (the minimum temperature ($^{\circ}C$), the relative humidity (%), the precipitation (mm), the duration of sunshine (hour) and etc.) for developing a estimating tools, which could forecast forest fire regime under future climate change condition. Results showed that forest fires in this area were mainly occurred when the maximum temperature was $10{\sim}200^{\circ}C$, when the relative humidity was 40~60%, and when the average wind speed was under 2m/s. And forest fires mainly occurred at 2~3 day after rainfall.

Development of electric safety control system for incapable operation of ELB and MCB using the low voltage distribution line (저압 배전선로의 누전 및 배선용 차단기의 오동작 방지를 위한 전기안전 제어장치 개발)

  • Kwak, Dong-Kurl;Shin, Mi-Young;Jung, Do-Young;Kim, Hyo-Jin;Baek, Seong-Hyun;Choi, Byung-Seub
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.371-372
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    • 2007
  • The major causes of electrical fire are classified to short circuit fault, overload fault, electric leakage and electric contact failure. The occurrence factor of the fire is electric arc or spark accompanied with electrical faults. Residual Current Protective Device (RCD), that is Earth Leakage Circuit Breaker(ELB) and Molded_case Circuit Breaker (MCB), of high sensitivity type used at low voltage wiring cuts off earth leakage and overload, but the RCD can't cut off electric arc or spark to be a major factor of electrical fire. As the RCDs which are applied low voltage distribution panel are prescribed to rated breaking time about 30[ms] (KS C 4613), the RCDs can't perceive to the periodic electric arc or spark of more short wavelength level. To be improved on such problem, this research development is proposed to a auxiliary control apparatus for RCD trip on electric arc or spark due to electrical fire. Some experimental results of the proposed apparatus is confirmed to the validity of the analytical results.

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A Study of Fire Prevention Measures for Single-person Households (1인 가구의 화재예방 대책 연구)

  • Kim, Jong Kouk;Han, Dong-Ho
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.1
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    • pp.424-431
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    • 2021
  • This study explores fire prevention measures for single-person households on the phenomenon of an increase in single-person households due to changes in the family structure due to low birthrate and aging population, full marriage, non-marriage, separation, bereavement, and returning to farming villages, and increased flexibility in the labor market. The factor that affects the fire of single-person households is the residential environment problem at the structural level. In terms of behavior, there is an increase in fire occurrence due to the rearing of companion animals. In order to prevent fires in single-person households, safety regulations without exceptions are needed to improve the residential environment at the structural level. At the behavioral level, it is necessary to expand the prevention and safety guidance of related organizations. In addition, as a measure to prevent fire caused by companion animals, manufacturers of electric ranges should develop safety devices to prevent fires caused by companion animals, such as an automatic power-off device or power supply using a timer. It can also be an important means to create and distribute promotional videos of measures necessary to safely raise companion animals, or to develop and distribute disaster preparedness programs implemented in virtual reality.

Copyright Protection for Fire Video Images using an Effective Watermarking Method (효과적인 워터마킹 기법을 사용한 화재 비디오 영상의 저작권 보호)

  • Nguyen, Truc;Kim, Jong-Myon
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.8
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    • pp.579-588
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    • 2013
  • This paper proposes an effective watermarking approach for copyright protection of fire video images. The proposed watermarking approach efficiently utilizes the inherent characteristics of fire data with respect to color and texture by using a gray level co-occurrence matrix (GLCM) and fuzzy c-means (FCM) clustering. GLCM is used to generate a texture feature dataset by computing energy and homogeneity properties for each candidate fire image block. FCM is used to segment color of the fire image and to select fire texture blocks for embedding watermarks. Each selected block is then decomposed into a one-level wavelet structure with four subbands [LL, LH, HL, HH] using a discrete wavelet transform (DWT), and LH subband coefficients with a gain factor are selected for embedding watermark, where the visibility of the image does not affect. Experimental results show that the proposed watermarking approach achieves about 48 dB of high peak-signal-to-noise ratio (PSNR) and 1.6 to 2.0 of low M-singular value decomposition (M-SVD) values. In addition, the proposed approach outperforms conventional image watermarking approach in terms of normalized correlation (NC) values against several image processing attacks including noise addition, filtering, cropping, and JPEG compression.

Occurrence of Rhizina Root Rot in a Black Pine (Pinus thunbergii) Forest Located at the Western Coastal Area in Korea and Its Spreading Patterns (서해안 곰솔림에서의 리지나뿌리썩음병 발생 및 확산 유형)

  • Lee, Seung-Kyu;Kim, Kyung-Hee;Kim, Yeon-Tae;Park, Ju-Yong;Lee, Sang-Hyun
    • Research in Plant Disease
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    • v.11 no.2
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    • pp.208-212
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    • 2005
  • At the survey of June, 2002, total 294 dead frees were found in 20 ha of Black pine (Pinus thunbergii) forest located in the western coastal region of Korean peninsula. The dead trees were scattered over the 27 place as groups of about ten trees each. As a result of the field survey on the relationship between the conditions of dead trees and the occurrence of fruiting bodies of Rhizina undulata around the dead and/or dying trees, from June 2002 to August 2004 in the four plots, the occurrence of infected trees was observed as a shape of an irregular concentric circle from the first infected tree and R. undulata was found mainly around the dead tree. Because there was no observation of any other insects and pathogens which would kill trees, the cause of tree death in groups was considered owing to R. undulata. From the analysis of the physical and chemical proper ties of the soil collected from the damaged areas, the pH of soil was between 4.6 and 5.8 and the contents of soil nutrients were very low. Any "fire" trace was not found at all the 27 damaged places in the area, Taean, Chungcheongnam-Do, which are generally known as an important factor to initiate development of the disease. Therefore, further examination is needed to verify precisely about other environmental factors related with the group dying of the Black pines in this area beside 'fire'.

A Study on Accident Prediction Models for Chemical Accidents Using the Logistic Regression Analysis Model (로지스틱회귀분석 모델을 활용한 화학사고 사상사고 예측모형 개발 연구)

  • Lee, Tae-Hyung;Park, Choon-Hwa;Park, Hyo-Hyeon;Kwak, Dae-Hoon
    • Fire Science and Engineering
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    • v.33 no.6
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    • pp.72-79
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    • 2019
  • Through this study, we developed a model for predicting chemical accidents lead to casualties. The model was derived from the logistic regression analysis model and applied to the variables affecting the accident. The accident data used in the model was analyzed by studying the statistics of past chemical accidents, and applying independent variables that were statistically significant through data analysis, such as the type of accident, cause, place of occurrence, status of casualties, and type of chemical accident that caused the casualties. A significance of p < 0.05 was applied. The model developed in this study is meaningful for the prevention of casualties caused by chemical accidents and the establishment of safety systems in the workplace. The analysis using the model found that the most influential factor in the occurrence of casualty in accidents was chemical explosions. Therefore, there is an urgent need to prepare countermeasures to prevent chemical accidents, specifically explosions, from occurring in the workplace.

Regional Analysis of Forest Eire Occurrence Factors in Kangwon Province (강원도 지역 산불발생인자의 지역별 유형화)

  • 이시영;한상열;안상현;오정수;조명희;김명수
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.3 no.3
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    • pp.135-142
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    • 2001
  • This study attempts to categorizes the factors of forest fire occurrences based on regional meteorologic data and general forest no characteristics of 18 cities and guns in Kangwon province. lo accomplish this goal, some statistical analyses such as analysis of variance, correspondence analysis and multidimensional scaling were adopted. To reveal the forest fires pattern of study region, a categorization process was conducted by employing the quantification approach which modified and quantified the metric-data of fire occurrence dates. Also, The fire occurrence similarity was compared by using multidimensional scaling for each study region. The major results are summarized as follows: It was found that the meteorological factors emerged as different to each region are average and maximum temperature, minimum dew point temperature and average and maximum wind speed. In the result of correspondence analysis representing relationships between fire causes and study regions, Kangrung is caused by arsonist, Chulwon, Hwachen and Yanggu caused by military factor, Sokcho and Chunchen caused by the debris burning, and Samchuk caused by general man-caused fires, respectively. Finally, the forest fire occurrence pattern of this study regions were divided into five areas such as, group I including Samchuk, Kangryung, Chunchen, Wonju, Hongchen and Hhoingsung, group II including Donghae, Taebaek, Yangyang and Pyongchang, group III including Jungsun, Chulwon and Whachen, group Ⅵ including Gosung, Injae and Yanggu, and group V including Shokcho and Youngwol.

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