• Title/Summary/Keyword: fire pattern

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A Study on the Analysis of the Combustion Behavior and Carbonization Pattern of Vinyl Flooring on Which a Real-Scale Combustion Test Was Performed (실물 연소 실험이 진행된 비닐장판의 연소거동 및 탄화 패턴 해석에 관한 연구)

  • Joe, Hi-Su;Choi, Chung-Seog
    • Fire Science and Engineering
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    • v.33 no.6
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    • pp.120-125
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    • 2019
  • A real-scale combustion test was conducted on a vinyl flooring in a divided space, with 50 mL of an inflammable liquid sprayed on it. The combustion behavior of the vinyl flooring was studied in real time, and the carbonization patterns of the surface and cross-sections of the carbonized vinyl floor were analyzed. When the flame ignited by gasoline reached its peak, a continuously flaming region, intermittent flaming region, plume region, etc., were formed. The combustion of 50 mL gasoline on vinyl flooring took 26 s, and a halo pattern was observed. This test involved spraying kerosene evenly on the vinyl flooring and attempting to ignite the flooring using a gas torch, which failed. After the combustion of the vinyl flooring was complete, its carbonized range was measured to be 600 mm in length and 380 mm in width, and the carbonized area was 1000 ㎟. Heat transformed the coated layer of surface of the carbonized vinyl flooring into a carbonized layer, which became harder. The analysis of cross-section of the boundary surface of the carbonized vinyl flooring using a stereoscopic microscope showed that the vinyl flooring was bubbling, and that the white boundary layer at the bottom of the coated layer had disappeared.

Study on the Standardization of Korean Pattern Identification for Wind Stroke (한국형 중풍변증 지표에 대한 신뢰도 연구)

  • Lee, Sun-Woo;Kang, Byeong-Kab;Kang, Baek-Gyu;Han, Deok-Jin;Lee, Jung-Wook;Shin, Sun-Ho;Moon, Byung-Soon;Lee, In
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.2
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    • pp.453-458
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    • 2008
  • This study aimed to develop an evaluation reliability of Korean pattern identification for wind stroke. We studied 643 patients with stroke and made a list of registry for each of them. The present study analyzed 553 cases, in which the resident’s pattern identification agreed with the specialist’s one, and the cases included five differentiation pattern: the fire-heat pattern (114), the dampness-phlegm pattern (157), the static blood pattern (11), the Yin deficiency pattern (81), and the Qi deficiency pattern (190). This study showed that none of the Cronbach's alpha reached 0.700, which is the general reliable level. The average Cronbach's alpha of each symptoms was 0.353 for the dampness-phlegm pattern, 0.571 for the fire-heat pattern, 0.443 for the Qi deficiency pattern, 0.451 for the Yin deficiency pattern, and 0.302 for the static blood pattern. This suggests the possibility that each pattern identification could be coincided with other symptoms, and it also shows the limits of pattern identification of this study that narrows the symptoms of paralysis patients into only a single pattern. Continuous compliments and researches should be done referring to this matter. However, the internal consistency analysis of all the pattern identification showed that every Cronbach's alpha were within the range of 0.670 to 0.703, and the Cronbach's alpha of the whole symptoms was evaluated as 0.692, which makes the reliability of the pattern identification as itself almost satisfactory to the general reliable level, and therefore, significant. In the future, continuous clinical research to develope this pattern identification for wind stroke actually applicable to stroke patients needs to be made through accumulating more cases, improving the objectivity.

Study on the Relation between Each Pattern Identification and Blood Lipid Level in Stroke Patients (중풍(中風)환자의 5개 변증(辨證)과 혈중지질의 상관관계 연구)

  • Shin, Hyun-Su;Kang, Byoung-Kab;Ahn, Jung-Jo;Yoo, Ho-Ryong;Kim, Yoon-Sik;Seol, In-Chan;Jo, Hyun-Kyung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.5
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    • pp.883-891
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    • 2010
  • The purpose of this study was to investigate the relation between each pattern identification such as Dampness-Phlegm, Fire-Heat, Deficiency of Qi, Deficiency of Yin and Blood Stagnation and blood lipid level in acute stroke patients. This study was done over patients hospitalized in 13 Oriental Medical Hospitals in the period of November 2006 to Jun 2009. Patients had been interviewed by residents and medical specialists who studied standard operation procedures in Fundamental Study for Syndrome of Oriental Medicine for Stroke. Study subjects consisted of group A that was distributed to specified pattern identification by medical specialist and discriminating program, group B that was distributed to specified pattern identification by medical specialist or discriminating program, and the control group that wasn't distributed to specified pattern identification by medical specialist and discriminating program. For the purpose of obtaining suitable result, we analyzed blood lipid level of each group by univariate analysis. In this study, there was not statistically significant relation between most of each pattern identification and blood lipid level except relation between Fire-Heat pattern group B and decreasing HDL cholesterol. Based on these results, it is suggested that Dampness-Phlegm would not be the independent predictors of hyperlipidemia unlike other studies that were presented in. More prospective studies between Fire-Heat and decreasing HDL cholesterol are to be done with more clinical data.

The observation on eating impact on psychological aspect (식생활이 정서에 미치는 영향에 대한 고찰)

  • Bang, Jung-Kyun
    • Journal of Oriental Neuropsychiatry
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    • v.16 no.2
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    • pp.125-133
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    • 2005
  • Object : This paper is designed to inquire into the influence of eating habits on the emotion of modem people. Method : The methodology is used that searches for materials such as books and treatises on the relationship between eating habits and emotion. Result : Meat used for fast food comes from cows that are fed the feed containing growth hormone and antibiotic. Growth hormone extremely supplements fire or yang within the body while antibiotics undermines the process of yin, leading to an accumulation of damp-heat and inflammation of ministerial fire. Additives contained in instant foods also impinge on the process of yin, leading to poor digestion, damp-heat toxins and ministerial fire. Excessive consumption of meat results in incomplete combustion of fat and hinders the formation of essence. Subsequently, ministerial fire becomes hyperactive as a result of the lack of yin energy. Increased meat consumption in the human diet is coupled with unhealthy eating pattern in which people eat too much for dinner and too quickly. Eating too much disturbs digestion, making it slow and incomplete, leading to excess damp-heat conditions, insufficient amount of vital essence and eventually hyperactive ministerial fire. Milk is considered a catalyst of faster growth, making it suitable for calves. Milk intake rapidly increases the balance of yang and eventually cause hyperactivity of ministerial fire. Conclusion : It is estimated that the eating habits of modern people cause the process of yang, making them feel restless, impatient and aggressive.

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Characteristics of Fire-induced Thermal-Flowfields in an Underground Utility Tunnel with Ventilation (화재 발생시 환기방식에 따른 지하공동구내 열유동 특성 연구)

  • Kim, Hong-Sik;Hwang, In-Ju;Kim, Yun-Je
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1845-1850
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    • 2003
  • The underground utility tunnels are important facility as a mainstay of country because of communication developments. The communication and electrical duct banks as well as various utility lines for urban life are installed in the underground utility tunnel systems. If a fire breaks out in this life-line tunnel, the function of the city will be discontinued and the huge damages are occurred. In order to improve the safety of life-line tunnel systems and the fire detection, the behaviors of the fire-induced smoke flow and temperature distribution are investigated. In this study we assumed that the fire is occurred at the contact or connection points of cable. Numerical calculations are carried out using different velocity of ventilation in utility tunnel. The fire source is modeled as a volumetric heat source. Three-dimensional flow and thermal characteristics in the underground tunnel are solved by means of FVM (Finite Volume Method) using SIMPLE algorithm and standard ${\kappa}-{\varepsilon}$ model for Reynolds stress terms. The numerical results of the fire-induced flow characteristics in an underground utility tunnel with different velocity of ventilation are graphically prepared and discussed.

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Improved Classification of Fire Accidents and Analysis of Periodicity for Prediction of Critical Fire Accidents (초대형화재사고 예측을 위한 화재사고 분류의 개선 및 발생의 주기성 분석)

  • Kim, Chang Won;Shin, Dongil
    • Journal of the Korean Institute of Gas
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    • v.24 no.1
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    • pp.56-65
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    • 2020
  • Forecasting of coming fire accidents is quite a challenging problem cause normally fire accidents occur for a variety of reasons and seem randomness. However, if fire accidents that cause critical losses can be forecasted, it can expect to minimize losses through preemptive action. Classifications using machine learning were determined as appropriate classification criteria for the forecasting cause it classified as a constant damage scale and proportion. In addition, the analysis of the periodicity of a critical fire accident showed a certain pattern, but showed a high deviation. So it seems possible to forecast critical fire accidents using advanced prediction techniques rather than simple prediction techniques.

A Numerical Investigation on Restrained High Strength Q460 Steel Beams Including Creep Effect

  • Wang, Weiyong;Zhang, Linbo;He, Pingzhao
    • International journal of steel structures
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    • v.18 no.5
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    • pp.1497-1507
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    • 2018
  • Most of previous studies on fire resistance of restrained steel beams neglected creep effect due to lack of suitable creep model. This paper presents a finite element model (FEM) for accessing the fire resistance of restrained high strength Q460 steel beams by taking high temperature Norton creep model of steel into consideration. The validation of the established model is verified by comparing the axial force and deflection of restrained beams obtained by finite element analysis with test results. In order to explore the creep effect on fire response of restrained Q460 steel beams, the thermal axial force and deflection of the beams are also analyzed excluding creep effect. Results from comparison infer that creep plays a crucial role in fire response of restrained steel beam and neglecting the effect of creep may lead to unsafe design. A set of parametric studies are accomplished by using the calibrated FEM to evaluate the governed factors influencing fire response of restrained Q460 steel beams. The parametric studies indicate that load level, rotational restraint stiffness, span-depth ratio, heating rate and temperature distribution pattern are key factors in determining fire resistance of restrained Q460 steel beam. A simplified design approach to determine the moment capacity of restrained Q460 steel beams is proposed based on the parametric studies by considering creep effect.

An Analysis on the Spatial Pattern of Local Safety Level Index Using Spatial Autocorrelation - Focused on Basic Local Governments, Korea (공간적 자기상관을 활용한 지역안전지수의 공간패턴 분석 - 기초지방자치단체를 중심으로)

  • Yi, Mi Sook;Yeo, Kwan Hyun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.1
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    • pp.29-40
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    • 2021
  • Risk factors that threaten public safety such as crime, fire, and traffic accidents have spatial characteristics. Since each region has different dangerous environments, it is necessary to analyze the spatial pattern of risk factors for each sector such as traffic accident, fire, crime, and living safety. The purpose of this study is to analyze the spatial distribution pattern of local safety level index, which act as an index that rates the safety level of each sector (traffic accident, fire, crime, living safety, suicide, and infectious disease) for basic local governments across the nation. The following analysis tools were used to analyze the spatial autocorrelation of local safety level index : Global Moran's I, Local Moran's I, and Getis-Ord's G⁎i. The result of the analysis shows that the distribution of safety level on traffic accidents, fire, and suicide tends to be more clustered spatially compared to the safety level on crime, living safety, and infectious disease. As a result of analyzing significant spatial correlations between different regions, it was found that the Seoul metropolitan areas are relatively safe compared to other cities based on the integrated index of local safety. In addition, hot spot analysis using statistical values from Getis-Ord's G⁎i derived three hot spots(Samchuck, Cheongsong-gun, and Gimje) in which safety-vulnerable areas are clustered and 15 cold spots which are clusters of areas with high safety levels. These research findings can be used as basic data when the government is making policies to improve the safety level by identifying the spatial distribution and the spatial pattern in areas with vulnerable safety levels.

Analysis of a Fire Case Caused by Heat Generation due to Cu2O Breeding (아산화동증식 발열에 의한 화재 사례의 분석)

  • Park, Jin-Young;Lee, Eui-Pyeong
    • Fire Science and Engineering
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    • v.34 no.2
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    • pp.54-63
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    • 2020
  • Although fires caused by heat generation due to Cu2O breeding in wire connections are well-known among fire investigators, there are few papers on the analysis and introduction of fire cases by heat generation due to Cu2O breeding. This study analyzed fire statistics caused by heat generation in electrical connections and the phenomena and features of heat generation due to Cu2O breeding. Then, a fire which occurred in the wire connection in a university lab by heat generation due to Cu2O breeding was analyzed in more detail. This fire case could reach a conclusion that heat generation due to Cu2O breeding caused a fire in the wire connection through the fire pattern investigation of fire origin, the visual investigation of wire connection, 3D CT, power-on-test, and stereoscopic microscopy, SEM and EDS analysis.

Noise Exposure according to the Time Activity Pattern and Duties of Firefighters (소방 공무원의 시간활동 양상과 직무에 따른 소음 노출 특성)

  • Lee, Lim-Kyu;Kang, Tae-Sun;Ham, Seung-Hon;Kim, Jung-In;Yang, Young-Suk;Yoon, Chung-Sik
    • Journal of Environmental Health Sciences
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    • v.37 no.2
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    • pp.94-101
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    • 2011
  • Objectives: The purpose of this study is to evaluate the noise exposures of firefighters according to their time-dependent activity patterns. Methods: Personal exposure levels were measured for six days and nights using noise dosimeters; three days and nights for on-duty tasks, the other days and nights for off-duty activities. Results: The total amount of time spent in the workplace was 13,677 min (67%), outside areas 4,833 min (23%), in transit 1,002 min (5%), and other indoor area 807 min (4%) during a working period. However, during off-days they spent 10,858 min (76%) at home, 1,382 min (10%) outdoors, 1,225 min (9%) other indoors, and 493 min (3%) in transit. As a result of individual exposure levels, TWA did not exceed 90 dBA of the occupational exposure limit for the majority of the firefighters, whereas the levels of Lmax were 119 dBA, which were higher than the noise levels of firefighters in USA. Sometimes during dispatching the levels of Lpeak exceeded the ACGIH exposure standard (140 dBC). The Leq levels in transit were higher than the levels in home and other indoors even though the activity time is short. Conclusions: This paper characterized the noise exposure patterns of firefighters in Korea. We suggest that special noise sources, including sirens and speaker phones, should be readjusted to reduce noise exposure.