• Title/Summary/Keyword: Burning

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구강작열감질환에 관한 고찰 및 의료분쟁 증례보고 (A Review of Burning Mouth Disorders)

  • 허윤경;정재광;최재갑
    • 대한치과의사협회지
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    • 제48권9호
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    • pp.688-695
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    • 2010
  • Burning mouth disorders (sometimes referred to as burning mouth syndrome) are characterized by a burning sensation in the tongue or other oral sites, usually in the absence of clinical and laboratory findings. Affected patients often present with multiple oral complaints, including burning, dryness and taste alterations. Burning mouth complaints are reported more often in women, especially after menopause. Typically, patients awaken without pain, but report increasing symptoms through the day and into the evening. Conditions that have been reported in association with burning mouth syndrome include chronic anxiety or depression, various nutritional deficiencies, diabetes and changes in salivary function. However, these conditions have not been consistently linked with the syndrome, and their treatment has had little impact on burning mouth symptoms. Recent studies have pointed to dysfunction of several cranial nerves associated with taste sensation as a possible cause of burning mouth disorders. The most common central mechanism that likely explains burning mouth disorders is a centrally mediated continuous neuropathic pain. Given in low dosages, benzodiazepine, tricyclic antidepressants or anticonvulsants may be effective in patients with burning mouth disorders.

소형 추진기관을 이용한 고체 추진제의 연소속도 측정 (Measuring Burning rate of Solid propellent using Small Propulsion Motor)

  • 정철영;김한준
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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    • pp.228-231
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    • 2011
  • 추진제의 연소속도는 추진기관을 설계할 때 반드시 필요한 요소이다. 추진제의 연소속도는 중립적 압력선도를 얻을 수 있는 추진제 그레인을 설계/제작하여 지상연소시험을 통해 압력을 확인하고 연소 속도 계산식의 계산을 통해 얻는다. 이렇게 얻어진 계산된 연소속도 값은 표준화된 추진제의 시편을 제작하여 스트렌드 버너에서 연소시켜 얻어진 추진제의 연소속도 값과 비교하여 정확한 연소속도 값을 확인하게 된다. 본 연구는 추진기관 설계에 필수요소인 추진제 조성에 따른 연소속도를 효율적으로 얻고자 소형 추진기관을 설계/제작/시험/분석 하였다.

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Biomass-burning에서 배출되는 미세입자 (PM2.5)의 배출원 구성물질 성분비 개발에 관한 연구 (A Study on the Source Profile Development for Fine Particles (PM2.5) Emitted from Biomass Burning)

  • 강병욱;이학성
    • 한국대기환경학회지
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    • 제28권4호
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    • pp.384-395
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    • 2012
  • This study was performed to develop the source profiles for fine particles ($PM_{2.5}$) emitted from the biomass burning. The multi-method research strategy included a usage of combustion devices such as field burning, fireplace, and residential wood burning to burn rice straw, fallen leaves, pine tree, and oak tree. The data were collected from multiple sources and measured water-soluble ions, elements, elemental carbon (EC), and organic carbon (OC). From this study, it turned out that OC (34~67%) and EC (1.2~39%) are the major components emitted from biomass burning. In the case of burning rice straw at field burning, OC (66.6%) was the most abundant species, followed by EC (4.3%), $Cl^-$ (3.6%), Cl (2.1%), and $SO^{2-}_4$(1.9%). Burning rice straw, fallen leaves, pine tree, and oak tree at fireplace, the amount of OC was 58.5%, 52.7%, 52.5%, and 61.2%, and that of EC was 1.2%, 18.4%, 36.5%, and 2.7%, respectively. The ratio of OC for the burning of pine tree and oak tree from the residential wood burning device was 56.9% and 34.3%, and that of EC was 25% and 38.6%, respectively. Applying the measured data with respect to the proportion of components emitted from biomass burning to reference model, it turned out that self-diagnosed result was appropriate level, and the result based on the model is in highly corresponding to actual timing of biomass burning.

Experimental Study on Turbulent Burning Velocities of Two-Component Fuel Mixtures of Methane, Propane and Hydrogen

  • Kido, Hiroyuki;Nakashima, Kenshiro;Nakahara, Masaya;Hashimoto, Jun
    • 한국연소학회지
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    • 제6권2호
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    • pp.1-7
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    • 2001
  • In order to elucidate the turbulent burning velocity of the two-component fuel mixtures, the lean and rich two-component fuel mixtures, where methane, propane and hydrogen were used as fuels, were prepared keeping the laminar burning velocity nearly the same value. Clear difference in the measured turbulent burning velocity at the same turbulence intensity can be seen among the two-component fuel mixtures with different addition rate of fuel, even under nearly the same laminar burning velocity. The burning velocities of lean mixtures change almost monotonously as changing addition rate, those of rich mixtures, however, do not show such a monotony. These phenomena can be explained qualitatively from the local burning velocities, estimated by considering the preferential diffusion effect for each fuel component. In addition, a prediction expression of turbulent burning velocity proposed for the one-component fuel mixtures can be applied to the two-component fuel mixtures by using the estimated local burning velocity of each fuel mixture.

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폐경 후 여성의 우울증에 수반된 구강 작열감 증후군(Burning Mouth Syndrome)에 대한 Gabapentin의 효과 (Effect of Gabapentin for the Treatment of Burning Mouth Syndrome Comorbid with Depression in Postmenopausal Women)

  • 김민정;김현석;박시성
    • 정신신체의학
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    • 제22권2호
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    • pp.138-142
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    • 2014
  • 구강 작열감 증후군(Burning mouth syndrom)은 기질적인 질환 없이 구강이 타는 듯한 통증을 호소하는 질환이다. 병인으로는 신경병증, 폐경, 영양불균형 등 여러 요인이 관련되어 있을 것으로 추정되며, 정신의학적으로는 우울증이 가장 잘 동반된다. 진통소염제, 호르몬제, 항전간제 및 항우울제 등이 치료로 시도되었으나 효과는 비특이적이다. 이 증례보고는 폐경 후 여성에서 우울증에 동반된 구강 작열감 증후군에 대한 gabapentin의 효과를 보고한다. 항우울제는 우울증상을 호전시켰지만 구강증상에는 효과가 없었다. Gabapentin을 12주간 하루 300mg 용량으로 추가 투여 후 구강증상은 주관적으로 유의하게 감소되었다. 폐경 후 여성에서 항우울제로 개선되지 않는 구강 작열감 증후군 환자에서 gabapentin의 추가 투여가 효과적일 수 있다.

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Chemical Composition of Post-Harvest Biomass Burning Aerosols in Gwangju, Korea

  • Kim, Young-J.;Ryu, Seong-Y.;Kang, Gong-U.
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2003년도 International Symposium on Clean Environment
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    • pp.79-84
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    • 2003
  • The main objective of this study was to investigate the chemical characteristics of post-harvest biomass burning aerosols from field burning of barley straw in late spring and rice straw in late fall in rural area in Korea. 12-hr integrated intensive sampling of $PM_{10}$ and $PM_{2.5}$ biomass burning aerosols had been conducted continuously at Gwangju, Korea 4-15 June 2001 and 8 October-14 November 2002. The fine and coarse particles of biomass burning aerosols were collected for mass, ionic, elemental, and carbonaceous species analysis. Average fine and coarse mass concentrations of biomass burning aerosols were measured to be 129.6, 24.2 ${{\mu}gm}^{-3}$ in June 2001 and 47.1, 33.2 ${{\mu}gm}^{-3}$ in October to November 2002, respectively. Exceptionally high level of $PM_{2.5}$ concentration up to 157.8 ${{\mu}gm}^{-3}$ well above 24-hour standard was observed during the biomass burning event days under stagnant atmosphere condition. During biomass burning periods dominant ionic species were $Cl^{-}$, ${NO_3}^{-}$, ${SO_4}^{2-}$, and ${NH_4}^{+}$ in fine and coarse mode. In the fine mode $Cl^{-}$ and ${KCl}^{+}$ were unusually rich due to the high content of the semiarid vegetation. High OC values and OC/EC ratios were also measured during the biomass burning periods. Increased amount of fine aerosols with high enrichment, which were originated from biomass burning of post-harvest agricultural waste, resulted in extremely severe particulate air pollution and visibility degradation in the region. Particulate matters from open field burning of agricultural wastes cause great adverse impact on local air quality and regional climate.

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Anodizing과 Burning 공정 혼합으로 표면처리 된 마그네슘합금(AZ31) 안경테 표면의 특성 연구 (The study of characterization about magnesium alloy eye-glasses case by anodizing and mixed method (anodizing+burning))

  • 유재용;임진환;유재인;김진희;박창훈;김기홍
    • 한국진공학회지
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    • 제16권3호
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    • pp.231-234
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    • 2007
  • 마그네슘 합금을 Anodizing과 Burning anodizing만으로만 표면 처리했을 때는 표면에 기공이 많이 발생 되었지만, anodizing 처리 후, burning 공정을 추가 하였을 때는 기공이 현저히 줄어들었다. 즉 burning 공정이 추가 되므로 인해 anodizing 공정의 단점인 기공의 봉공처리가 가능함을 알았다. 또한 막 두께도 anodizing 만 처리 했을 때 보다 더 균일하게 성장함을 보았다.

Chemical Compositions of Primary PM2.5 Derived from Biomass Burning Emissions

  • Ichikawa, Yujiro;Naito, Suekazu
    • Asian Journal of Atmospheric Environment
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    • 제11권2호
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    • pp.79-95
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    • 2017
  • A number of field studies have provided evidence that biomass burning is one of the major global sources of atmospheric particles. In this study, we have collected $PM_{2.5}$ emitted from biomass burning combusted at open burning and laboratory chamber situations. The open burning experiment was conducted with the cooperation of 9 farmers in Chiba Prefecture, Japan, while the chamber experiment was designed to evaluate the characteristics of chemical components among 14 different plant species. The analyzed categories were $PM_{2.5}$ mass concentration, organic carbon (OC), elemental carbon (EC), ionic components ($Na^+$, ${NH_4}^+$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Cl^-$, ${NO_3}^-$ and ${SO_4}^{2-}$), water-soluble organic carbon (WSOC), water-insoluble inorganic carbon (WIOC), char-EC and soot-EC. OC was the dominant chemical component, accounting for the major fraction of primary $PM_{2.5}$ derived from biomass burning, followed by EC. Ionic components contributed a small portion of $PM_{2.5}$, as well as that of $K^+$. In some cases, $K^+$ is used as biomass burning tracer; however, the observations obtained in this study suggest that $K^+$ may not always be suitable as a tracer for biomass burning emissions. Also, the results of all the samples tested indicate relatively low values of char-EC compared to soot-EC. From our results, careful consideration should be given to the usage of $K^+$ and char-EC as indicators of biomass burning. The calculated ratios of WSOC/OC and WIOC/OC were 55.7% and 44.3% on average for all samples, which showed no large difference between them. The organic materials to OC ratio, which is often used for chemical mass closure model, was roughly estimated by two independent methods, resulting in a factor of 1.7 for biomass burning emissions.

An Ultrasonic Measurement Model to Predict a Reflected Signal from Non-Linear Burning Surface of Solid Propellants

  • Song, Sung-Jin;Kim, Hak-Joon;Oh, Hyun-Taek;Lee, Sang-Won;Song, Seung-Hyun;Kim, In-Chul;Yoo, Ji-Chang;Jung, Jung-Yong
    • 비파괴검사학회지
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    • 제27권6호
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    • pp.531-540
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    • 2007
  • While determination of the solid propellant burning rates by ultrasound, it has been reported that the frequent data scatters were caused by two major factors; 1) variation in the acoustical properties, and 2) non-linear burning of a solid propellant sample under investigation. This work is carried out for the purpose of investigating the effect of non-linear burning of solid propellant samples. Specifically, we propose an ultrasonic measurement model that can predict the reflections from solid propellant surfaces with non-linear burning by the combination of two ingredients; 1) a pulse-echo ultrasonic measurement model for a planar, circular reflector imbedded in the second medium in an immersion set-up, and 2) an efficient model of non-linear burning surfaces with a number of small, planar circles. Then, we demonstrate the capability of the proposed measurement model by simulation of the surface echo signals from four different burning surfaces that have been generated by the combination of two factors; the base shape (flat or paraboloidal) and the surface roughness (perfectly smooth or randomly rough). From the simulation presented here, we can confirm the fact that the non-linear burning of the propellant can cause the waveform change of the burning surface echo and the corresponding spectrum variation.

산소부화조건에서의 반응기구 검토 (Examination of Optimal Reaction Mechanism in Oxygen Enriched Condition)

  • 한지웅;이창언
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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    • pp.247-253
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    • 2003
  • Burning velocities of conventional methane flame and oxygen-enriched methane flame were determined by experimentally and numerically at atmospheric pressure in order to examine the validity of various detailed reaction mechanisms in oxygen-enriched flame. The schlieren system was adopted to obtain the burning velocity of flame stabilized on a circular nozzle. Premix code was employed to compute the burning velocity. Three reaction mechnisms were tested at several oxygen enrichment level, whose names are GRI 3.0, MB(Miller and Bowman) and LKY(Lee Ki Yong) reaction mechanism. Sensitivity analysis was also performed to discriminate dominantly affecting reaction on burning velociy. The results showed that conventional reaction mechanisms originally based on methane-air flame were underpredict the burning velocity at high oxygen-enrichment level. The modified GRI 3.0 reaction mechanism based on our experimental results was suggested and shows a good agreement in estimating the burning velocity and the NO number density of oxygen-enriched flame.

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