• Title/Summary/Keyword: Fire severity

Search Result 110, Processing Time 0.021 seconds

Normalized Difference Vegetation Index based on Landsat Images Variations between Artificial and Natural Restoration Areas after Forest Fire (산불 지역 인공·자연복원에 따른 Landsat영상 기반 식생지수 비교)

  • Noh, Jiseon;Choi, Jaeyong
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.25 no.5
    • /
    • pp.43-57
    • /
    • 2022
  • This study aims to classify forest fire-affected areas, identify forest types by the intensity of forest fire damage using multi-time Landsat-satellite images before and after forest fires and to analyze the effects of artificial restoration sites and natural restoration sites. The difference in the values of the Normalized Burned Ratio(NBR) before and after forest fire damage not only maximized the identification of forest fire affected and unaffected areas, but also quantified the intensity of forest fire damage. The index was also used to confirm that the higher the intensity of forest fire damage in all forest fire-affected areas, the higher the proportion of coniferous forests, relatively. Monitoring was conducted after forest fires through Normalized Difference Vegetation Index(NDVI), an index suitable for the analysis of effects by restoration type and the NDVI values for artificial restoration sites were found to no longer be higher after recovering the average NDVI prior to the forest fire. On the other hand, the natural restoration site witnessed that the average NDVI value gradually became higher than before the forest fires. The study result confirms the natural resilience of forests and these results can serve as a basis for decision-making for future restoration plans for the forest fire affected areas. Further analysis with various conditions is required to improve accuracy and utilization for the policies, in particular, spatial analysis through forest maps as well as review through site checks before and immediately after forest fires. More precise analysis on the effects of restoration will be available based on a long term monitoring.

Injury Severity Analysis of Truck-involved Crashes on Korean Freeway Systems using an Ordered Probit Model (순서형 프로빗 모형을 적용한 고속도로 화물차 사고 심각도)

  • Kang, Chanmo;Chung, Younshik;Chang, Yoo Jin
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.39 no.3
    • /
    • pp.391-398
    • /
    • 2019
  • In general, truck-involved crashes increase severity in terms of both injury level and crash impact level. Recently, although the frequency and fatality of truck-involved crashes in Korea are rising, their associative studies are very limited. Therefore, the objective of this study is to identify critical factors influencing on injury severity of truck-involved crashes on Korean freeway system. To carry out this objective, this study uses an ordered probit model (OPM) based on a 6-year crash dataset from 2012 to 2017. From the analysis, eight variables were found to have a great effect on injury severity: older driver, crash speed, rear-end collision, number of vehicles involved, drowsy driving, nighttime (0:00 to 6:00) driving, overturn or rollover, and vehicle's fire after crash. However, injury severity was less severe in crashes under snowy condition and crashes to traffic facilities (i.e., crash alone).

A Study on Safety of Hydrogen Station (수소충전소의 안전성에 관한 연구)

  • Ko, Jae-Wook;Lee, Dae-Hee;Jung, In-Hee
    • Journal of the Korean Institute of Gas
    • /
    • v.13 no.1
    • /
    • pp.45-51
    • /
    • 2009
  • A safety assessment was performed through the process analysis of hydrogen station. The purpose of this study provides basic information for the standard establishment about hydrogen stations. The processes of hydrogen stations were classified by four steps (process of manufacture, compression, storage, charge). FMEA (Failure Mode and Effect Analysis) method was applied to evaluate safety. Each risk element is following; S (severity), O (occurrence), D (detection). And the priority of order was decided by using RPN (Risk Priority Number) value multiplying three factors. Scenarios were generated based on FMEA results. And consequence analysis was practiced using PHAST program. In the result of C.A, jet fire and explosion were shown as accident types. In case of leakage of feed line in PSA process, concentration of CO gas is considered to prevent CO gas poisoning when the raw material that can product CO gas was used.

  • PDF

Analysis of Mobility Constraint Factors of Fire Engines in Vulnerable Areas : A Case Study of Difficult-to-access Areas in Seoul (화재대응 취약지역에서의 소방특수차량 이동제약요인 분석 : 서울시의 진입곤란지역을 대상으로)

  • Yeoreum Yoon;Taeeun Kim;Minji Choi;Sungjoo Hwang
    • Journal of the Korean Society of Safety
    • /
    • v.39 no.1
    • /
    • pp.62-69
    • /
    • 2024
  • Ensuring swift on-site access to fire engines is crucial in preserving the golden time and minimizing damage. However, various mobility constraints in alleyways hinder the timely entry of fire engines to the fire scene, significantly impairing their initial response capabilities. Therefore, this study analyzed the significant mobility constraints of fire engines, focusing on Seoul, which has many old town areas. By leveraging survey responses from firefighting experts and actual observations, this study quantitatively assessed the frequency and severity of mobility constraint factors affecting the disaster responses of fire engines. Survey results revealed a consistent set of top five factors regarding the frequency and disturbance level, including illegally parked cars, narrow paths, motorcycles, poles, and awnings/banners. A comparison with actual road-view images showed notable consistency between the survey and observational results regarding the appearance frequency of mobility constraint factors in vulnerable areas in Seoul. Furthermore, the study emphasized the importance of tailored management strategies for each mobility constraint factor, considering its characteristics, such as dynamic or static. The findings of this study can serve as foundational data for creating more detailed fire safety maps and advancing technologies that monitor the mobility of fire engines through efficient vision-based inference using CCTVs in the future.

A Study on Improvement of Crash Discrimination Performance for Offset and Angular Crash Events Using Electronic X-Y 2-Axis Accelerometer (전자식 X-Y 이축 가속도 센서를 이용한 오프셋 및 경사 충돌에 대한 충돌 판별 성능 개선에 관한 연구)

  • 박서욱;전만철
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.11 no.1
    • /
    • pp.128-136
    • /
    • 2003
  • In today's design trend of vehicle structure, crush zone is fiequently reinforced by adding a box-shaped sub-frame in order to avoid an excessive deformation against a high-speed offset barrier such as EU Directive 96/97 EC, IIHS offset test. That kind of vehicle structure design results in a relatively monotonic crash pulse for airbag ECU(Electronic Control Unit) located at non-crush zone. As for an angular crash event, the measured crash signal using a single-axis accelerometer in a longitudinal direction is usually weaker than that of frontal barrier crash. Therefore, it is not so easy task to achieve a satisfactory crash discrimination performance for offset and angular crash events. In this paper, we introduce a new crash discrimination algorithm using an electronic X-Y 2-axis accelerometer in order to improve crash discrimination performance especially for those crash events. The proposed method uses a crash signal in lateral direction(Y-axis) as well as in longitudinal direction(X-axis). A crash severity measure obtained from Y-axis acceleration is used to improve the discrimination between fire and no-fire events. The result obtained by the proposed measure is logically ORed with an existing algorithm block using X-axis crash signal. Simulation and pulse injection test have been conducted to verify the performance of proposed algorithm by using real crash data of a 2,000cc passenger vehicle.

The Study on Compartment Fire Experiment According to Fire Load (화재하중에 따른 구획화재 실험 연구)

  • Kweon, Oh-Sang;Kim, Heung-Youl
    • Fire Science and Engineering
    • /
    • v.31 no.6
    • /
    • pp.16-22
    • /
    • 2017
  • In Korea, performance-based fire safety designs are being discussed to deal with the various risks of fire in complex and diverse types of structure. However, performance-based fire safety designs are not actively employed because it is difficult to estimate the fire characteristics related to the various factors in buildings. In this study, real scale fire tests were conducted based on fire severity levels and fire loads provided in He New Zealand Building Code, in order to use the results as guidelines and fundamental data for performance-based designs. In the real scale fire tests conducted in a 10MW full-scale calorimeter, wood cribs were placed in a $2.4(L){\times}3.6(W){\times}2.4(H)m$ mock-up of a compartment which had one $0.8(L){\times}2.0(H)$ opening for different fire loads and heating was continued until all of the wood cribs were burned down. The heat release rate started to increase rapidly 90 seconds after the wood cribs caught fire. In the test with a fire load level 1, the maximum heat release rate of 4743.4 kW was reached at 244 second. In the test with fire load level 2, a maximum heat release rate of 5050.9 kW was reached at 497 second. In the test with fire load level 3, a maximum heat release rate of 4446.9 kW was reached at 677 second.

A Patient with Liver Fire Flaming Upward and Metabolic Syndrome Improved by Korean Medicine: A Case Report (대사증후군이 동반된 간화상염 변증 환자에 대한 한의정신요법 병행 한의치료 증례보고)

  • Jun-Hee, Cho;Jung-Hwa, Lim;Bo-Kyung, Kim
    • Journal of Oriental Neuropsychiatry
    • /
    • v.33 no.4
    • /
    • pp.485-495
    • /
    • 2022
  • The purpose of this study is to report a case of a patient with pattern identification of liver fire flaming upward and metabolic syndrome improved by Korean medicine. The patient felt completely lost. She was treated for headache, insomnia, and metabolic syndrome with Korean medicine and psychotherapy. Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Pattern Identification Tool for Insomnia (PIT-Insomnia), Minnesota multiphasic personality inventory-2 (MMPI-2), and bioelectrical impedance analysis (BIA) were used for assessment. During treatment for six months, the patient stopped taking headache pills. Her blood pressure was stabilized. Her body weight, body fat, body mass index (BMI), and visceral fat decreased significantly. The sum of ISI, PSQI, PIT-insomnia also decreased significantly. Her Ego strength increased in the MMPI-2 supplementary scale. We assume that Korean medicine treatment through acupuncture, herbal medicine, and psychotherapy is effective in treating pattern identification of liver fire flaming upward and metabolic syndrome.

Fire-Induced Forest Disturbance Mapping by Using QuickBird Imagery (QuickBird 화상을 이용한 산불 삼림교란도 작성)

  • Kim, Choen
    • Korean Journal of Remote Sensing
    • /
    • v.25 no.1
    • /
    • pp.85-94
    • /
    • 2009
  • This paper presents the capability to use QuickBird imagery for effects of forest disturbance in Okgye burned area. Particular attention of this paper deals with the NBR-derived mapping burn severity on QuickBird imagery to locate reliable rehabilitation(namely, secondary succession) over postfire surface. Comparisons of the mapping forest disturbance derived from QuickBird NBR data and the mapping burn severity derived from Landsat ${\Delta}NBR$ data show substantial agreement (KHAT value =0.7886). The method calculated from the correlation between QuickBird wetness and Landsat ETM+ band7 may have application to forest harvest disturbance.

A Study on Estimation and Management of Loss Due to Catastrophic Accident (화학공장의 중대사고에 따른 예상손실액 산정 및 대책연구)

  • 구남주;엄성인;고재욱
    • Journal of the Korean Society of Safety
    • /
    • v.14 no.4
    • /
    • pp.120-125
    • /
    • 1999
  • This study evaluated the effect of the accidents caused by fire, explosion, and toxic gas release by using SuperChems, quantitative hazardous material release modeling software, which estimates the potential area of damage. According to the loss severity, the appropriate risk management principles can be applied. Risk management is divided into the two methods which are risk control and risk financing. Risk control includes risk avoidance, risk spreading and diversification, and risk reduction. Risk financing includes risk retention and risk transfer. The results of this study can help the related company determine the appropriate reserve fund and the amount to be insured against the third party losses according to the estimated loss severity.

  • PDF

A Study on Winter-Covered Optical Satellite Imagery for Post-Eire Forest Monitoring

  • Kim, Choen;Park, Seung-Hwan
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.274-274
    • /
    • 2002
  • Damage to forest trees, caused by wildfire, changes their spectral reflectance signature. This factor led to the initiation of a research project at the Remote Sensing & GIS Laboratory, Kookmin University, to determine if multispectral data acquired by IKONOS could provide fire scar and bum severity mapping. This paper will present detail mapping of burned areas in the eastern coast of Korea with IKONOS imagery. In addition, a single post-burn Landsat-7 ETM+ data was used to compare with IKONOS, the study area. Burn severity map based on IKONOS image was found to be affected by strong topographic illumination effects in the mountain forest. But it has better the delineation of the bum-scarred area. In this study the NDVI was analyzed for geometric illumination conditions influenced by topography(slop, aspect and elevation) and shadow(solar elevation and azimuth angle).

  • PDF