• Title/Summary/Keyword: burning up

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Analysis of Electrical and Thermal Signal for Series Arc in Electrical Contact (전선의 접속부에서 직렬아크에 의한 전기적 및 열적 신호 분석)

  • Kim, Doo Hyun;Hwang, Dong Kyu
    • Journal of the Korean Society of Safety
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    • v.30 no.5
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    • pp.1-7
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    • 2015
  • This paper is aimed to analyze the electrical and thermal signal such as ignition possibility, ignition time, thermal characteristics and arc fault power that are associated with electrical fire in case of the occurrence of series arc at IV wiring used for interior wiring at commercial power source. In order to analyze the signal, series arc was induced by generating the constant vibration through vibrating device in the one phase (R phase) and ignition possibility was analyzed along the condition of current value by adding cotton material to the contact point of wiring. The ignition time is shortened as the electric current value increased, burning time is not associated with current value and the temperature rose up to $740^{\circ}C$ though it was not ignited. It was checked out that the temperature was the energy source enough that can generate the fire related with insulation aging of wiring and the inflammable. The possibility of electrical fire by series arc was shown as more than 12% at 5A, more than 42% at 20A and arc showed 27W at 5A, 180W at 20A. It was confirmed that the possibility of electrical fire exists at the condition as above and the circuit breaker did not operate. This data can be used as the reference value for the investigation of electrical fire or development of the circuit breaker.

Comparison between Major Depressive Disorder & Hwabyung (Culture Bound Syndrome) using the SCL-90-R (SCL-90-R을 이용한 화병과 주요우울장애의 비교)

  • Chung, Sun-Yong;Park, Jong-Hoon;Kim, Sang-Ho;Whang, Wei-Wan;Kwon, Jung-Hye;Kim, Jong-Woo
    • Journal of Oriental Neuropsychiatry
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    • v.15 no.2
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    • pp.45-51
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    • 2004
  • Hwabyung is a Korean culture bound syndrome and translated as anger syndrome at DSM-IV. And it is caused by the suppression of anger and has characteristics of chest discomfort, burning up as physical symptoms, and mortification, chagrin as psychological symptoms. It is very common in the field of psychiatry in Korea with Major Depressive Disorder (MDD). * Objective : 95 patients with MDD or Hwabyung, who visited the department of psychiatry in Korea University Medical Center or oriental medical hospital of Kyunghee Medical Center from May 2003 to August 2003, were selected for the study to compare between Major Depressive Disorder and Hwabyung. * Methods : The Structured Clinical Interview Schedule for DSM-IV (SCID) and Hwa-Byung Diagnostic Interview Schedule (HBDIS) were conducted for diagnosis. And Symptom Check List-90-Revised (SCL-90-R) was carried out for comparison between MDD and Hwabyung. * Result : Among the 95 patients, MDD group was 23 persons, Hwabyung group was 36 persons, and MDD plus Hwabyung group was 36 persons and it occupied 37.9%. MDD plus Hwabyung group had higher scores than any other groups in the whole dimensions of SCL-90-R. Hwabyung group had higher scores than MDD group in somatization, anxiety, hostility, Global Severity Index(GSI) and positive symptom total (p<.05) of SCL-90-R, but two groups had no difference in obsessive-compulsive, interpersonal-sensitivity, depression, phobic anxiety, paranoid ideation, psychoticism, positive symptom distress index of SCL-90-R. * Conclusion : These result showed that Hwabyung is similar to MDD at the point of depression and psychoticism but more severe at somatization, anxiety and anger than MDD.

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A Systematic Review on Drug Safety for Molsidomine, Nicorandil and Trimetazidine (Molsidomine, Nicorandil, Trimetazidine의 안전성 관련 체계적 고찰)

  • Jeong, Kyeong Hye;Lee, Euni
    • Korean Journal of Clinical Pharmacy
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    • v.26 no.2
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    • pp.172-180
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    • 2016
  • Background: Ischemic heart disease is the most common type of heart disease and an important cause of death in Korea. Among marketed anti-anginal medications, molsidomine, nicorandil, and trimetazidine are approved in Korea with unique mechanism of actions. As these drugs are not approved by the US Food and Drug Administration, the access to the up-to-dated and comprehensive safety-related information has been less than optimal from drug information resources used by Korean pharmacists. Methods: A systematic review was conducted using Embase and Korean manuscripts to compile safety updates for these medications. Out of 418 articles from keyword searches, 52 studies were reviewed in full to compare adverse effects (AEs) with the approved package inserts (PI). Results: Molsidomine related adverse effects were mostly mild or moderate, but anxiety, palpitation, epigastric pain, and sexual potency reduction were additional AEs found from the review not listed in PI. Although PI has included ulceration in oral cavity and gastrointestinal tracts including anus by nicorandil, the Korea FDA recently recommended adding corneal, genital, and skin ulcers to the approved PI. Trimetazidine induced Parkinsonism, worsening of the symptoms for patients diagnosed with Parkinson's disease, gastrointestinal burning, and muscle cramps were additionally identified AEs not listed in PI for trimetazidine. Conclusion: Continuous evaluations of the safety profile of these agents are needed to balance the risks and benefits to provide evidence-based safety counseling to the patients. In addition, more focused efforts on spontaneous reporting are warranted by healthcare professionals to safeguard patients against AEs.

Suppression of Methane Emission from Rice Paddy Soils with Fly ash Amendment

  • Ali, Muhammad Aslam;Oh, Ju-Hwan;Kim, Pil-Joo
    • Korean Journal of Environmental Agriculture
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    • v.26 no.2
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    • pp.141-148
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    • 2007
  • Fly ash, a by-product of the coal-burning industry, and a potential source of ferro-alumino-silicate minerals, which contains high amount of ferric oxide and manganese oxide (electron acceptors), was selected as soil amendment for reducing methane $(CH_4)$ emission during rice cultivation. The fly ash was applied into potted soils at the rate of 0, 2, 10, and 20 Mg $ha^{-1}$ before rice transplanting. $CH_4$ flux from the potted soil with rice plants was measured along with soil Eh and floodwater pH during the cropping season. $CH_4$ emission rates measured by closed chamber method decreased gradually with the increasing levels of fly ash applied but rice yield significantly increased up to 10 Mg $ha^{-1}$ application level of the amendment. At this amendment level, total seasonal $CH_4$ emission was decreased by 20% along with 17% rice grain yield increment over the control. The decrease in total $CH_4$ emission may be attributed due to suppression of $CH_4$ production by the high content of active and free iron, and manganese oxides, which acted as oxidizing agents as well as electron acceptors. In conclusion fly ash could be considered as a feasible soil amendment for reducing total seasonal $CH_4$ emissions as well as maintaining higher grain yield potential under optimum soil nutrients balance condition.

A Study on the Prediction of Fire Load in case of a Train Fire (철도 차량 화재시 화재강도 예측을 위한 연구)

  • Yang, Sung-Jin;Chang, Jung-Hoon;Gang, Chan-Yong
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.2101-2108
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    • 2008
  • Most of train fires which occur in usual cases do not grow up significantly on a large scale enough to bring about casualties and harmful damages. However, the consequence of some train fire accidents can be devastating disaster so that it would be even recorded in history in unusual cases. Accordingly, such a probability of fire disaster cannot be ignored in aspect of the railway safety assesment. A scale of injury and damage is very difficult to predict and analyze. Because it is depend on various factors, i.e. fire load, burning period, facilities, environment condition, and so on. Thus, a prediction of fire load could be understood as a one methodology to estimate railway safety assesment. The summation method which is one of them is used to evaluate the overall fire load by assuming that sum of heat release rate per unit area or mass of each composite material equals the total. However, since the train fire is classified into a compartment fire in under-ventilation condition. The summation method do not estimate a fire load completely. In this journal, Various methods to predict fire load are introduced and evaluated. Especially the fire simulation tool FDS(Fire Dynamics Simulator)which is based on the CFD(Computational Fluid Dynamics) is introduced, too. Through the FDS simulation, numerical analyses for the fire load and flame spread are performed. Then, these results of the simulation are validated through the comparison study with the experimental data. Then, limitations and approximations including in simulation process are discussed. The future direction of research is proposed.

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Percutaneous Absorption of Recombinant h-EGF through Normal, Stripped and First-Degree Burn Skin (상피세포 성장인자의 경피흡수: 정상피부, 각질제거피부 및 화상피부에 있어서)

  • Cho, Ae-Ri;Lee, Jung-Uk;Ahn, Byung-Lak;Chung, Joo-Young;Koh, Yeo-Wook;Shim, Chang-Koo
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.29-32
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    • 1996
  • In vivo and in vitro skin permeation of $recombinant^{125}$ I-EGF through normal, stripped and the first degree burn skin were studied. The in vitro skin permeation rate through the first degree burn skin $(296\;cpm/cm^2/hr)$ and the stripped skin $(1131\;cpm/cm^2/hr)$ were 3.5 times and 13 times higher, respectively, as compared with the one through normal skin. In vivo absorption study with the first degree burn skin, the peak concentration of EGF in the skin was achieved at 1-3 hr and decreased afterward up to 8 hr with an elimination constant of $1.31{\times}10^{-3}\;g/ml/hr$. To investigate the higher elimination rate of EGF in burn skin, binding and metabolism studies were conducted. No significant metabolism of EGF in burn skin $(100^{\circ}C,\;5-second\;burning)$ was observed. With the presence or unlabelled-EGF $^{125}I-EGF$ permeation through the burn skin showed higher permeation rate than the one without unlabelled-EGF. The result nay indicate that EGF-receptor binding play a role in determining the skin permeation rate.

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A Study on Thermal Analytical Model for a Dry Dual Clutch (건식 듀얼 클러치의 열해석 모델에 대한 연구)

  • Liu, Hao;Lee, J.C.;Noh, Y.J.;Cho, J.H.;Lee, H.R.;Koh, J.E.;Kang, J.W.
    • Journal of Drive and Control
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    • v.12 no.1
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    • pp.1-8
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    • 2015
  • The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.

Production of DME from CBM by KOGAS DME Process (KOGAS DME 공정을 이용한 CBM으로부터 DME 생산)

  • Cho, Won-Jun;Mo, Yong-Gi;Song, Taek-Yong;Lee, Hyen-Chan;Baek, Young-Soon;Denholm, Douglas;Ko, Glen;Choi, Chang-Woo
    • Journal of Hydrogen and New Energy
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    • v.22 no.6
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    • pp.925-933
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    • 2011
  • The traditional feedstock for dimethyl ether (DME) has been natural gas obtained by pipeline from a nearby natural gas or oil field. This report focuses on other feedstock: Coal bed methane (CBM). The resource availability and suitability of CBM for DME manufacturing have been investigated. CBM in a short time has become an important industry, providing an abundant clean-burning fuel and also suggesting as a feedstock for gas industry. The use of CBM will have very little impact on the KOGAS' DME process design and economics up to 50 vol% of $CO_2$ in the CBM source. Many of the CBM sources in Asia are high in $CO_2$, but pose no difficulties for the KOGAS' DME plant. Since tri-reformer requires substantial $CO_2$ in its feed, no $CO_2$ removal from the CBM feed is needed. The $CO_2$ in the CBM means that less $CO_2$ needs to be recycled from the downstream in the process.

An Investigation of Performance Characteristics of A Biogas-Fueled Motorcycle Engine (바이오 가스 이륜차 기관의 성능 특성 연구)

  • Huynh, Thanh Cong;Chiem, Tran Lam;Vu, Thi Kim Chau
    • Journal of Hydrogen and New Energy
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    • v.23 no.4
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    • pp.373-381
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    • 2012
  • To determine the performance characteristics of motorcycle engine using biogas for practical use, the intake system of a 110 cc motorcycle engine is properly modified to operate with biogas as a fuel. Biogas is a potentially renewable fuel for replacing gasoline in future, but it has high percentage of $CO_2$ that could lead to slow the burning rate of biogas-air mixture and cause instability in combustion. Thus, the performance characteristics of biogas-fueled motorcycle engines could be different from those of gasoline motorcycle engines. In this paper, the important parameters of performance characteristics (such as: power output, thermal efficiency, fuel consumption, exhaust emission,${\cdots}$) of biogas-fueled motorcycle engine are studied and estimated with change of engine speed and load. The obtained results when operating with biogas are used to compare with that of gasoline fuel under the same operating conditions. Engine speed in the experimental is changed from 1500 rpm (idle-mode) up to 3500 rpm by a step of 500 rpm. Engine load is changed from zero to maximum load with the help of an exciting voltage device from generator-type dynamometer. The experimental results show that the tested engine operated with richer biogas-air mixture than that of gasoline-air mixture under the same test conditions. Biogas-fueled engine gives a higher fuel consumption and lower thermal efficiency under the same power output. Brake thermal efficiency of biogas engine is found to be about 3% lower than gasoline-fueled motorcycle engine for whole range of speed. Exhaust emission of biogas-fueled motorcycle engine (such as: CO, HC) is found to be lower than the limitation level of the emission standards of Vietnam for motorcycle engines (CO <4.5% HC <1200 ppm).

Investigation of an Apartment Fire - Site Surveys and Burn Tests for Estimation of the Progress on Initial Fire Spread - (공동주택의 화재조사 - 현장조사 및 연소실험에 의한 초기 화재확대과정 추정 -)

  • Nam, Dong-Gun;Hasemi, Yuji
    • Fire Science and Engineering
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    • v.23 no.4
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    • pp.120-129
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    • 2009
  • Identification of the exact cause of a building fire is generally difficult, because the source and initially ignited objects are often severely damaged or even lost during the early stages of the fire. We made an experimental attempt to reasonably estimate the burning during the very early stages of a fire, and identify its source and causes. The case we studied was an apartment fire, which occurred in Tokyo, in July 2002. The fire was extinguished just after flashover, and the on-site investigations suggested the fire started from the TV and TV stand, which had been damaged so severely that it was difficult to conclude that the TV was the ultimate cause of the fire, simply from the on-site investigation. We conducted a series of burn tests using a TV and other products identical to those actually used in the apartment. Tests were set-up and procedures were carefully studied to recreate the conditions of the articles that remained, and of the room itself. The tests demonstrated that the conditions in the apartment could be recreated only when the fire started inside the TV and came into close contact with dresser.