• Title/Summary/Keyword: Pre-chamber

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Construction History of the Old House "IMCHEONGGAK" in Andong and Estimation of its Original Structure -Focused on the 'Inner chamber' and the 'Sarang section'- (안동 "임청각(臨淸閣)"의 건축 이력과 원형 가구(架構) 추정 -사랑채와 안채를 중심으로-)

  • Lee, Jong-Seo
    • Journal of architectural history
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    • v.25 no.2
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    • pp.31-44
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    • 2016
  • Imcheong-gak[臨淸閣] was a familial residence constructed in the early half of the Joseon dynasty period. It was partially destroyed by a fire during the 1590s war[壬辰倭亂] with the Japanese, and another fire that was caused between 1631 and 1634. The inner chamber[An-chae] and the Sarang section[Sarang-chae] today is the result of a partial reconstruction that took place back in 1626 and again around 1634. The residence also went through some changes because the new Ondol[溫突] heating system had to be applied to the structure. Based upon sections that remain in their original forms, we can presume that the Imcheong-gak residence originally had an inner chamber which was composed of the following elements: A main structure which was built upon a foundation featuring a Matbae[맞배] roof, two "Ik'rang[翼廊, flank]" sections on the East and West sides of the inner chamber, and a "Haeng'rang[行廊, passage]" structure on the opposite side of the main structure. Unlike the main structure, other portions of the inner chamber were all built directly upon the ground, and showed multiple stories, with Matbae roofs of their own. We can also assume that the Sarang section in the south would have been a pre-Ondol[溫突] bedroom, with a Board platform[板房] and a Gomi-ceiling[Gomi-banza] fashion.

The Field Emission Properties of Density Controlled Carbon Nanotubes

  • Lee, Tae-Young;Kim, Do-Yoon;Yoo, Ji-Beom;Park, Chong-Yun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.845-848
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    • 2003
  • We investigated a field emission property of CNTs grown on pre-treated substrates by $H_{2}$ plasma etching method in vacuum chamber (<${10^{-7}}$ Torr). To improve the emission characteristics, various catalysts and buffer layers were used. The morphology and density of catalyst layer was controlled by the different plasma pre-treatment conditions, resulting in the control of the growth characteristics of CNTs.

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Fundamental Experiments of a Compression Ignition Engine Using Gaseous Fuel (가스체 연료를 사용하는 압축착화기관에 관한 기초적 연구)

  • ;太田 幹郞
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.2
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    • pp.147-157
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    • 1996
  • Natural gas is gaining more attraction as a future fuel in particular both for environmental protection and energy conservation. In order to bring about more widespread use of gaseous engines, the technology capable of achieving output and efficiency performance equivalent to that of diesel engines needs to be developed. In the present paper, the requirements of the pilot torch from pre-chamber for ensuring ignition and promoting combustion are discussed by means of taking high-speed flame photography and system can run with leaner mixture of various fuels comparing to the electric plug ignition system cause the ignition delay period ignited with the torch and the combustion period are very short in spite of changing A/F of gaseous fuels in the main chamber. However, the suitable piston-cavity design for the use of lower-hydrocarbon fuels such as propane and butane must be discussed increasingly in the mear future.

A Study on the Combustion Characteristics of Lean Mixture by Radicals Induced Injection in a Constant Volume Combustor (2) (정적연소기에서 라디칼 유도분사를 이용한 희박혼합기의 연소특성에 관한 연구 (2))

  • 박종상;강병무;이명준;하종률;정성식
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.3
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    • pp.19-26
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    • 2004
  • A prior fundamental study was executed using a constant volume chamber to improve the burning properties of lean pre-mixture by the injection of active radicals generated in the sub-chamber. In consequence, RI method shows remarkable progress in the aspects of burning velocity and combustible lean limit compared with SI method. In this study, the necessary additional works have been performed to be based on the former results. We changed parameters as the initial temperature and the initial pressure of mixture. And the effects of residual gas at issue in a real engine were investigated. As a result, the effects of initial temperature were significant, but on the other hand, those of initial pressure were slight. The correlation of passage hole number between overall passage hole area was grasped. And the more detailed analysis is required on residual gas.

Development of Three-dimensional Chamber-type Glucose Sensor Using Micromachining Technology (마이크로머시닝 기술을 이용한 3차원 마이크로 챔버형 글루코스 센서의 개발)

  • Kim Sung Ho;Kim Chang Kyo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.1
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    • pp.24-28
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    • 2005
  • A micromachined biochip with a three dimensional silicon chamber was developed for the construction of biosensors. Anisotropic etching was used fur the formation of the chamber on the p-type silicon wafer(100) and then was glued to the Pyrex glass bottom-substrate with pre-deposited platinum electrode. The electrochemical characterization of its Pt electrode and Ag/AgCl reference electrode was investigated.

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RADICAL IGNITION TECHNIQUE IN A CONSTANT VOLUME CHAMBER

  • Park, J.S.;Ha, J.Y.;Yeom, J.K.;Lee, J.S.;Lee, C.J.;Chung, S.S.
    • International Journal of Automotive Technology
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    • v.8 no.3
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    • pp.269-274
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    • 2007
  • A prior fundamental study was executed using a constant volume chamber (CVC) to improve the burning characteristics of lean pre-mixture by the injection of active radicals generated in the sub-chamber of the CVC. The Radical ignition (RI) technique shows remarkable progress in the burning velocity and combustible lean limit compared with the results of the spark ignition (SI) technique. The optimum design value of the sub-chamber geometry is near $0.11cm^{-1}$ for the ratio of the total area of the holes to the sub-chamber volume $(A_h/V_s)$. In this study, based on the former experimental results, the additional works have been performed to examine the effects of the geometry change in the number $(N_h)$, the total section area $(A_h)$, and diameter $(D_h)$ of the passage holes on the combustion characteristics in the CVC. Also ambient conditions such as the initial temperature and the initial pressure of the mixture were selected as experimental parameters and the effects of residual gas at the chamber on the combustion characteristics were investigated. As a result, the correlation between the passage hole number and overall passage hole area was grasped. The effects of the initial temperature were significant, but on the other hand, those of the initial pressure were weak. A more detailed analysis on the residual gas is required in the future.

Cor triatriatum(A case report) (삼중방심 치험 1예)

  • 정경영
    • Journal of Chest Surgery
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    • v.16 no.3
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    • pp.331-336
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    • 1983
  • Cor triatriatum is a rare congenital malformation of the heart, in which a septum stretches in a transverse or oblique plane through the left atrium, thus separating it into two compartments. The upper one connects with the pulmonary veins, and the lower one connects with the left ventricle. Due to the rarity of, and great difficulty in-diagnosing, cor trlatrlatum, data On the surgery of this disease are of necessity very limited and so accurate pre-operative diagnosis was very difficult to make. `We experienced a case of the cyanotic congenital heart disease which was diagnosed as a large atrlal septal defect with streaming venous blood from inferior vena cava to left atrium through atrial septal defect in August, 1982. We found that there were transverse septum in the left atrium through atrlal septal defect, the pulmonary venous drainage were located in the upper chamber of the left atrium, and the lower chamber was connected with the left atrial appendage, mitral valve and `left ventricle. But our case had not any opening in this transverse septum and the right atrium was connected with the upper chamber of the left atrium through the upper part of the atrlal septal defect, and was communicated with the lower chamber of the left atrium through the lower part of the atrlal septal defect. We excised the transverse septum and repair this atrial septal defect with Woven Dacron patch accompanying with the drainage of coronary sinus to right atrium. The post-operative course was not eventful and he was discharged with good result on the post-operative 8th day, and has been in good .condition up to now for longer than 10 months.

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Effects of a Four-week Clothing Program for Improving Vascular Compliance on Heat Tolerance (혈압 관리를 위한 4주간의 착의훈련이 고혈압 전단계자의 내열성에 미치는 영향)

  • Choi, Jeong-Wha;Park, Joon-Hee
    • The Korean Journal of Community Living Science
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    • v.22 no.3
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    • pp.445-454
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    • 2011
  • This study was performed on 5 prehypertensive male participants to investigate the effects of the clothing program for improving the vascular compliance on heat tolerance. The clothing program means the alternate stimulation of the temperature using clothes. The participants wore two different garments with $1.5^{\circ}C$ difference in the temperature inside clothing in a climatic chamber ($18.8{\pm}0.2^{\circ}C$, $38{\pm}3%RH$) alternately for 4 weeks. Heat tolerance tests were conducted in the climatic chamber of $35.2{\pm}0.5^{\circ}C$, $54{\pm}3%RH$ before and after the clothing program. The results were as follows. The $\overline{T}$sk, Tr and heart rate were lower in the post test than in the pre test (p<.01). The whole body and local sweat rates as well as systolic and diastolic blood pressures had reduced the tendencies in the post test. Participants felt less wet and more comfortable in the post test than in the pre test(p<.01). These results showed that the clothing program through the alternate stimulation of the temperature positively affected the improvement of heat tolerance.

A Study on Crack Propagation of Solid Propellant by Rapid Pressurization (고속가압에 의한 고체추진제의 균열진전평가에 관한 연구)

  • Ha, Jaeseok;Kim, Jaehoon;Yang, Hoyoung
    • Journal of the Korean Society of Propulsion Engineers
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    • v.16 no.6
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    • pp.79-84
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    • 2012
  • An experiment of rapid pressurization-induced crack propagation of solid propellant was conducted by using a windowed test chamber. A pre-cracked specimen of solid propellant is installed in the chamber, and highly compressed nitrogen gas in an accumulator pressurizes the chamber until the chamber pressure reaches set-up pressure to make the chamber depressurization. Pressure-time trace was obtained from the experimental result, and pressurization rate was defined from the trace. In this study, three pressurization rates (64.34, 73.86 and 85.44 MPa/s) are considered, and propagation lengths are measured. Also, a progression of the crack propagation recorded by a high-speed digital camera is presented.

A Study on Crack Propagation of Solid Propellant by Rapid Pressurization (고속압력하중부가에 의한 고체추진제의 균열진전평가에 관한 연구)

  • Ha, Jae-Seok;Kim, Jae-Hoon;Yang, Ho-Young
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2012.05a
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    • pp.539-544
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    • 2012
  • An experiment of rapid pressurization-induced crack propagation of solid propellant was conducted by using a windowed test chamber. A pre-cracked specimen of solid propellant is installed in the chamber, and highly compressed nitrogen gas in a accumulator pressurizes the chamber until the chamber pressure reaches set-up pressure to make the chamber depressurization. Pressure-time trace was obtained from the experimental result, and pressurization rate was defined from the trace. In this study, three pressurization rates (64.34, 73.86 and 85.44 MPa/s) are considered, and propagation lengths are measured. Also, a progression of the crack propagation recorded by a high-speed digital camera is presented.

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