• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제29회 추계학술대회논문집
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• pp.243-247
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• 2007

하이브리드 추진에서 연소특성을 나타내는 후퇴율 식을 초기 포트면적으로 나눈 산화제 유속이 고려된 고체연료 유속의 관계식으로 표현하였다. 초기 포트면적을 고려한 산화제 유속을 이용하여 반복 수행 없이 연소율을 쉽게 구할 수 있었고, 고체연료 유속 관계식으로 연료 형상을 간단히 설계할 수 있는 기법에 대한 연구를 수행하였다. 본 연구의 실험에서는 연료로 PE, 산화제로 GOX를 사용하였으며, 연소시간을 다양하게 하여 포트면적 변화에 따른 유속의 변화를 고려하였다. 하이브리드 추진에서, 산화제 유속의 지수가 0.5에 근접할 경우 후퇴율 관계식 보다는 고체연료 유속 관계식을 사용하는 것이 더 적합함을 확인하였다.

• 한국입자에어로졸학회지
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• 제9권1호
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• pp.7-21
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• 2013

Twelve-hour size-resolved atmospheric aerosols were measured to determine size distributions of water-soluble organic carbon(WSOC) during daytime and nighttime, and to investigate sources and formation pathways of WSOC in individual particle size classes. Mass, WSOC, ${NO_3}^-$, $K^+$, and $Cl^-$ at day and night showed mostly bimodal size distributions, peaking at the size range of $0.32-0.55{\mu}m$(condensation mode) and $3.1-6.2{\mu}m$(coarse mode), respectively, with a predominant condensation mode and a minor coarse mode. While ${NH_4}^+$ and ${SO_4}^{2-}$ showed unimodal size distributions which peaked between 0.32 and $0.55{\mu}m$. WSOC was enriched into nuclei mode particles(< $0.1{\mu}m$) based on the WSOC-to-mass and WSOC-to-water soluble species ratios. The sources and formation mechanisms of WSOC were inferred in reference to the size distribution characteristics of inorganic species(${SO_4}^{2-}$, ${NO_3}^-$, $K^+$, $Ca^{2+}$, $Na^+$, and $Cl^-$) and carbon monoxide. Nuclei mode WSOC was likely associated with primary combustion sources during daytime and nighttime. Among significant sources contributing to the condensation mode WSOC were homogeneous gas-phase oxidation of VOCs, primary combustion emissions, and fresh(or slightly aged) biomass burning aerosols. The droplet mode WSOC could be attributed to aqueous oxidation of VOCs in clouds, cloud-processed biomass burning aerosols, and small contributions from primary combustion sources. From the correlations between WSOC and soil-related particles, and between WSOC and sea-salt particles, it is suggested that the coarse mode WSOC during daytime is likely to condense on the soil-related particles($K^+$ and $Ca^{2+}$), while the WSOC in the coarse fraction during nighttime is likely associated with the sea-salt particles($Na^+$).

• 한국안전학회지
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• 제31권5호
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• pp.54-60
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• 2016

In this study, tank truck incidents of road transport of hazardous materials to experimental investigated the potential fire hazard. Real scale fire was to perform experiments for on this qualitative and quantitative data collection and analysis. Particularly affected by radiant heat from the flames caused and damage estimates range investigated accordingly. Flame temperature, internal temperature of tank and emitted radiation from the flames was investigated. The flame of light oil spill caused a fire at a temperature of about $300^{\circ}C$ high in comparison with the methanol by combustion of diesel and methanol, according to the difference, the flame duration changes varies depending on the Burning rate. Depending on spill rate(30, 60, 90 and $120{\ell}/min$) and the longer the duration of the flame important factors for the internal temperature of tank lorry rise was found. Road accident in a fire caused by leakage of hazardous was could the higher the damaged. Therefor, Fire suppression activities should be required in particular to be around.

• The Korean Journal of Pain
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• 제3권2호
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• pp.165-171
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• 1990

The reflex sympathetic dystrophy syndrome (RSDS) consists of sustained burning pain and tenderness, vasomotor instabilitiy, swelling, occasional functional instability, trophic skin change and edema of extremity following trauma, peripheral nerve injury, spinal cord injury, infection, burn and other etiologic factors. The most important thing in RSDS is to start the treatment as soon as the disease was diagnosed. Most patients with RSDS respond dramatically and permanently to sympathetic blocks if treatment is instituted before irreversible trophic changes. The characteristic radiological finding in RSDS is a patchy osteoporosis in the cancellous bone. Periarticular hyperactivity is seen in RSDS by Tc99m bone scan. We have managed 4 cases of RSDS. The methods of management and effects are as follows: 1) In case 1, 28 lumbar sympathetic blocks in both sides were performed. The patient did not complain of pain or tenderness and the limping improved. 2) In case 2, 7 lumbar sympathetic blocks were performed, but we could find only a slight improvement in the symptoms. 3) In case 3, 8 stellate ganglion blocks were carried out. The patient refused the treatment of RSDS because of the lack of rapid improvement. 4) In case 4, total 64 stellate ganglion blocks were carried out; the patient was permanently improved.

• 한국응용과학기술학회지
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• 제23권2호
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• pp.147-152
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• 2006

The accidents occurred by unstable material which is easily exploded or burnt up were caused by heat and collision under the condition of relatively low temperature without oxygen, have been reported frequently. However, the amount of the unstable material is getting higher by development of fine ceramic research area even though its dangerous characteristic is disregarded. This research studied a heat stability and measured boiling point of various carpet material. Carpet has been used in home as well as general indoor usage. Now a day, carpet material which is hardly burnt has been on commercial, but its detailed unstable conditions is not mentioned. This research reports the measurement of the initial temperature of generation heat and heat-radiation change on differential scanning calorimeter (DSC). The DSC data of nylon bulked continuous filament (N-BCF) yam 100%, nylon (NY), poly propylene (PP), and a new material named polytrimethylene terephthalate (PTT) are studied and researched about the effect of them using TGA, furnace, and direct-burning experiment.

• 한국추진공학회지
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• 제21권5호
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• pp.37-45
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• 2017

연소 중인 고체추진제는 일반적으로 소화가 어렵지만, 연소실 내의 압력을 급격하게 강하시키면 추진제는 동적소화가 일어난다. 본 연구에서는 복합형 고체 추진제의 조성별 소화특성에 따른 실험적 연구에 대해 기술하였다. 폐쇄형 연소 챔버에 노즐 및 파열판을 장착하여 압력 강하시점, 압력 강하율, 초기 압력을 조절할 수 있는 실험장치를 구성하였다. 이 장치를 이용하여 추진제 조성별로 소화가 가능한 임계 압력 강하율을 실험적으로 연구하였다. 실험 결과 산화제의 입자크기, 산화제 혼합비, 알루미늄 첨가 유무가 고체 추진제의 소화 특성에 큰 영향을 주는 것으로 나타났다.

• 한국추진공학회지
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• 제16권1호
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• pp.9-15
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• 2012

하이브리드 연소실의 국부 압력과 속도변화를 고려하는 비정상 내탄도 해석모델을 제안하고 이를 바탕으로 연소실 내 국부영역에서 내탄도 특성인자의 변화를 도출하였다. 해석 모델 검증을 위하여 연소실 전후단의 압력을 측정한 실험결과와 해석결과를 비교하여 실험과 해석결과가 유사함을 확인하고 연소 효율을 평가 하였다. 하류방향으로 산화제 유량이 변화하므로 이에 따른 연소실 국부영역의 압력, 온도, 연료의 후퇴율 및 연소가스의 유속 변화를 정량적으로 고찰하였다.

• 한국군사과학기술학회지
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• 제27권3호
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• pp.428-435
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• 2024

The important factors in the design of the gun propellant are impetus, flame temperature and pressure. In this paper, we considered a nitrocellulose based propellant composition that replaced sensitive NG(Nitroglycerin) with RDX(Cyclotrimethylenetrinitramine) and DEGDN(Diethylene glycol dinitrate) which high energy and low sensitivity. Particle size and content of RDX are the two main factors that affect the burning stability of RDX-based propellants. Among them, the characteristics of the propellant according to the particle size of RDX were confirmed. The relative combustion rate(R.Q., Relative Quickness) of the propellant changed according to the RDX particle size, and internal ballistics of properties of propellant were also varied. The particle size of RDX can be confirmed as a major factor in the combustion and internal ballistics characteristics of the propellant.

• 대한한의학원전학회지
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• 제20권2호
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• pp.175-193
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• 2007

A theory of the school which attach great importance to moxibustion therapy was more developed from 'Ge Hong(葛洪)', 'Wang Tao(王燾)' up to "BianQueXinShu(扁鵲心書)" of 'Dou Cai(竇材)' in Song Dynasty. The first volume of "BianQueXinShu" was described about the principles of health preserving method, diagnosis, treatment related with meridian system, support Yang theory, moxibustion therapy over the 10 chapters and in the continued 3 chapters, explained the symptoms and related moxibustion therapies. The summary is as follows. The Yang energy is the essence of the human body and it is minutely explained in "Hwangdineijing(黃帝內經)". However, the younger scholars after 'Zhang Zhongjing(張仲景)' held different views with "Hwangdineijing" so they didn't control serious diseases. Supporting the Yang energy, it will be possible to human body in good health and long life and perennial youth and longevity. To do like this, the first important thing is a moxibustion, the second is a Taoist hermit medication(丹藥) and the third is well usage of Radix Aconiti Lateralis Preparata. According to the sequence of Yang energy deficiency, the stages of diseases are classified as Ordinary Gi(平氣), Latter deficient state(微虛), The more deficient state(甚虛), Exhausting state(將脫), Exhausted state(已脫) and in the consideration of each stage, it is used gradually with warm-natured berbs, warm-acrid herbs, warm-heated herbs and moxibustion therapy. If it comes to the stage of Exhausted state, the Yang energy is too weak to treat a disease. Therefore it is easy to harm human body with usage the treatment of the Purgationist school theory or the Cold and cool medical school theory, so it is needed a great attention to use these therapies. To summarized the keynote of 'Du Jae''s moxibustion therapy, the one is a minority of selection of points(1$^{\sim}$2 acupuncture points), the second is a majority of moxibustion units(50$^{\sim}$500 units), and the other is a focused selection of points on spleen and kidney(especially Gwanwon, CC4). And in this book, it was explained concretely about the size of moxibustion, according to the experiment with mentioned size, the burning time of moxibustion was almost 4 min 40 sec, so the big size moxibustion was one of the characteristic of moxibustion therapy revealed in this book. Also it was used 'Suseongsan(睡聖散)' - a kind of analgesic herb complexes - to reduce a pain during the usage of moxibustion therapy in this book. To develop the moxibustion theory, it is more investigated in the future that there wasn't significant relation between Gwanwon(CC4) and spleen and kidney meridian in theory, compared to many used Gwanwon(CC4) in the prescription, where as mentioned the importance of spleen and kidney in treatment, that considering the burning time(1 unit - 4 min 40 sec, 12 units an hour, maximum 288 units a day) there were no guidances about meals, sleeping, stool and urine, and that there was no concrete study about the toxicity of 'Suseongsan' as analgesic moxibustion therapy.

• 한국기후변화학회지
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• 제4권2호
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• pp.115-126
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• 2013

최근 국내 배출원 특성을 고려하여 생물성 연소에 대한 배출목록(emission inventory)을 추가하려는 연구가 이루어지고 있으나, 국내 현황을 반영한 실증 연구는 현재까지 거의 이루어진 바가 없는 실정이다. 따라서 앞으로 배출목록에 대한 기후 대기 통합관리시스템이 진행될 경우, 효과적인 배출원 관리를 위해 생물성 연소의 온실가스 배출 특성에 대한 연구가 필요한 시점이다. 본 연구에서는 숯가마에서 발생하는 온실가스 배출 특성을 파악하기 위하여 숯가마 모형장치를 이용하여 현장실험을 실시했다. 또한, 참나무의 점화, 탄화, 출탄하는 시기와 내부 온도 변화를 고려하여 굴뚝에서 배출되는 온실가스($CO_2$, $CH_4$, $N_2O$)를 직접 포집하여 분석하였다. 온실가스 배출계수 산정 결과, $CO_2$ 배출계수는 668 g/kg, $CH_4$ 배출계수는 20 g/kg이며, $N_2O$ 배출계수는 0.01 g/kg으로 나타났다. 본 연구에서 개발한 온실가스 배출계수를 사용하여 국가 배출량을 산정한 결과, $CO_2$ 배출량은 46,040 ton/yr, $CH_4$ 배출량은 1,378 ton/yr, $N_2O$ 배출량은 0.69 ton/yr으로 나타났다. GWP를 이용하여 총 배출량을 산정한 결과, 연간 $75,201ton\;CO_2eq.$으로 나타났으며, 참나무는 바이오 매스에 포함되기 때문에 연소하는 과정에서 발생하는 $CO_2$는 총 배출량에서 제외되므로 숯가마에서 발생하는 국내 순배출량은 연간 $29,161ton\;CO_2eq.$으로 추정되었다.