SiC 필라멘트를 이용한 소염 직전의 확산화염 온도 계측

심성훈,신현동,Shim, Sung-Hoon,Shin, Hyun-Dong 대한기계학회 2002 大韓機械學會論文集B Vol.26 No.11

The thin SiC filament technique has been employed to identify the possibility of measuring flame temperature, and especially unstable near-extinction flame temperature in an oxidizer deficient ambience, by comparing the relative visible (non-IR) luminosities of SiC filaments with thermocouple measured temperature in co-flowing, laminar propane/air diffusion flames. The results show good agreement between the digitized relative visible luminosity profiles of the SiC filaments and temperature profiles measured using a thermocouple at temperatures above $700^{\circ}C$, although, a non-linear calibration is probably required far the whole temperature range. The highest radial peak temperature exists near to the nozzle exit. and the centerline temperatures were virtually unchanged with increasing flame height in an oxidizer deficient near-extinction flame.

평판 경계층 확산화염에서의 국부적 가속현상에 관한 실험적 연구

심성훈,하지수,신현동 대한기계학회 1988 대한기계학회논문집 Vol.12 No.4

본 연구에서는 연료분출에 박리가 있는 경우와 없는 경우 각각에 대하여 화염 대 근처의 국부가속 현상이 박리에 의하여 어떻게 영향을 받는가를 실험적으로 규명하 고, 나아가서 종래에 행해져 왔던 관련 연구 결과를 재검토할려고 한다. The main purpose of this study is to investigate the local velocity acceleration in a boundary layer diffusion flame over a flat plate. In order to know the effect of separation on the local velocity acceleration, two typical cases, flows with and without separation, are considered. For these cases, flow visualization using paraffine smoke tracers has been made. Mean velocity and r.m.s. value of fluctuating velocity are measured by using a laser Doppler velocimeter. In addition, measurements of time-mean concentration and time-mean temperature have been made. Time-mean density profiles have been obtained from the data of concentration and temperature. The obtained results are summarized as follows : (1) In the case without separation, the local velocity acceleration is clearly observed near the visible flame zone for all flow conditions. On the while, in the case with serration, the local velocity acceleration is observed only at low free stream velocity and high fuel injection velocity. As increasing the free stream velocity or decreasing the fuel injection velocity, it is not distinctly observed in the mean velocity profile. (2) The r.m.s. value of fluctuating velocity is significantly decreased by combustion in the case with separation. But in the case without separation, the r.m.s. value is increased near the visible flame zone in comparison with cold flow. In both cases, the peak value of r.m.s. appeared just at the visible flame zone, where the mean velocity gradient is not too high.

부동산투자회사(REITs)도입의 필요성과 방안

심성훈 江原大學校 經營硏究所 2000 經營科學硏究 Vol.25 No.-

전류예측기를 이용한 10비트 저전력 전류구동 CMOS A/D 변환기 설계

심성훈,권용복,윤광섭 대한전자공학회 1998 電子工學會論文誌, C Vol.c35 No.10

본 논문에서는 휴대용 영상신호처리 시스템에 집적화할 수 있는 전류예측기와 모듈형 기준전류원을 이용한 10비트 저전력 전류구동 CMOS A/D 변환기를 설계하였다. 전류예측기와 모듈형 기준 전류원을 사용함으로써 2단 플래시구조를 갖는 A/D 변환기에 비해 비교기와 기준전류원의 개수를 줄일 수 있게 되었고, 따라서 설계된 A/D변환기의 저전력 동작이 가능하였다. 설계된 10비트 저전력 전류구동 CMOS A/D 변환기는 0.6㎛ n-well single-poly triple metal CMOS 공정을 사용하여 제작되었다. +5V 단일 공급전압하에서 동작할 때 측정된 전력소모는 94.4mW이며, 아날로그 입력 전류범위는 16㎂에서 528㎂로 측정되었으며, INL과 DNL은 각각 ±1LSB, ±0.5LSB이하로 나타났다. 또한 10MSamples/s의 변환속도를 나타내었고, 제작된 10비트 전류구동 CMOS 4/D 변환기의 유효 칩면적은 1.8㎜ x 2.4㎜이다. In this paper, an 10 bit current-mode CMOS A/D converter with a current predictor is designed with a CMOS process to be integrated into a portable image signal processing system. A current predictor let the number of comparator reduce to 70 percent compared with the two step flash architecture. The current magnitude of current reference is reduced to 68 percent with a modular current reference. The designed 10 bit Low-power current-mode CMOS A/D converter with a current predictor is simulated with HSPICE using 0.6$\mu\textrm{m}$ N-well single-poly triple-metal CMOS process parameters. It results in a conversion rate of 10MSamples/s. A power consumption is measured to be 94.4mW at single +5V supply voltage. The 10 bit A/D converter fabricated using the same process occupies the chip area of 1.8mm x 2.4mm.

스테로이드를 투여 받는 환자에서 발생한 Nocardia farcinica 뇌 종양 1예

심성훈,박혜인조,김충종,전재현,김의종,오명돈,김남중,최강원 대한감염학회 2008 감염과 화학요법 Vol.40 No.5

Nocardiosis occurs mostly in the immunocompromised patients. N. farcinica is known to have resistance to some antibiotics and significant increase in morbidity and mortality in patients requiring long-term treatment. Nocardia farcinica infection, especially brain abscess, has not been reported in Korea. Here, we report a case of N. farcinica brain abscess in a patient receiving steroid treatment. The patient was a 64 year-old male with gouty arthritis, He received steroid for more than two months, because of allopurinol-hypersensitivity syndrome with skin rash. After three months of steroid therapy, he visited other hospital with mild fever and left thigh pain and was diagnosed of intramuscular abscess due to gram positive bacilli. One month later, he visited our hospital with right side weakness and was diagnosed as brain abscess. The causative organism turned out to be N. farcinica, which was confirmed by means of 16S rRNA sequencing. Antibiotics were selected by E-test results and treatment was successful.

1-G 진동대 실험을 이용한 시트파일 보강재의 액상화 및 피해 방지 효과

심성훈,윤종찬,손수원,김진만 한국지진공학회 2020 한국지진공학회논문집 Vol.24 No.5

Earthquake preparedness has become more important with recent increase in the number of earthquakes in Korea, but many existing structures are not prepared for earthquakes. There are various types of liquefaction prevention method that can be applied, such as compaction, replacement, dewatering, and inhibition of shear strain. However, most of the liquefaction prevention methods are applied before construction, and it is important to find optimal methods that can be applied to existing structures and that have few effects on the environment, such as noise, vibration, and changes in underground water level. The purpose of this study is to estimate the correlation between the displacement of a structure and variations of pore water pressure on the ground in accordance with the depth of the sheet file when liquidation occurs. To achieve this, a shaking table test was performed for Joo-Mun-Jin standard sand and an earth pressure, accelerometer, pore water pressure transducer, and LVDT were installed in both the non-liquefiable layer and the liquefiable layer to measure the subsidence and excess pore water pressure in accordance with the time of each embedded depth. Then the results were analyzed. A comparison of the pore water pressure in accordance with Hsp/Hsl was shown to prevent lateral water flow at 1, 0.85 and confirmed that the pore water pressure increased. In addition, the relationship between Hsp/Hsl and subsidence was expressed as a trend line to calculate the expected settlement rate formula for the embedded depth ratio.

고온 연소가스 재순환을 적용한 상용 생활폐기물 소각로의 가스 배출 특성

심성훈,정상현 한국폐기물자원순환학회 2016 한국폐기물자원순환학회지 Vol.33 No.6

Characteristics of the exhaust gas of a commercial scale (7.2 ton/day) municipal wastes incinerator with recirculation of its high temperature combustion gas were investigated. High temperature combustion gas made by incineration was entrained by an air jet and re-used for incineration. Air was preheated to 384-512oC and diluted to have an oxygen concentration of 16-17%. Incineration of municipal wastes with the preheated and diluted air made extremely uniform and stable flames. Concentrations of nitric oxide (NOx), carbon monoxide (CO), oxygen (O2), and carbon dioxide (CO2) in flue gas were measured at the boiler exit and the stack, simultaneously. Averaged concentrations of NOx and CO were reduced to 54.2 ppm and 3.1 ppm at the boiler exit and to 49.8 ppm and 6.0 ppm at the stack, respectively, at a reference oxygen concentration of 12% without any post treatment of NOx and when the averaged outlet temperature of the combustion chamber was 904oC. The measured NOx emission was only 29% of that of a conventional municipal incinerator. Simultaneous reduction of NOx and CO is significant. Averaged concentrations of O2 and CO2 were 9.7% and 8.6% at the boiler exit and 14.6% and 4.9% at the stack, respectively.

A Case of Meningococcal Sepsis and Meningitis with Complement 7 Deficiency in a Military Trainee

심성훈,허정연,김의종,조강원 대한감염학회 2013 Infection and Chemotherapy Vol.45 No.1

Complement component 7 (C7) deficiency leads to the loss of complement lytic function, and affected patients show increased susceptibility to encapsulated organisms infection, especially Neisseria meningitidis . Recently, we have experienced a 20-year-old military trainee with meningococcal sepsis and meningitis who was diagnosed as having C7 deficiency based upon the undetectable serum C7 protein on radioimmunoassay. This case emphasizes that although C7 deficiency is rare immune disorder, it is important to be aware of possibility about late complement deficiency among patients who present with meningococcal disease.

상용 생활폐기물 소각로의 NOx 저감을 위한 고온 연소가스 재순환장치 개발

심성훈,정상현 한국폐기물자원순환학회 2015 한국폐기물자원순환학회지 Vol.32 No.7

It is known that lowering of peak temperature of flame reduces NOx emission in combustion process. Low oxygen concentration of diluted combustion air reduces peak flame temperature, but makes flame unstable. So increasing of temperature of reactants is needed to enhance flame stability. Mixing of high temperature combustion gas with combustion air makes low oxygen concentration and increases air temperature simultaneously. Low oxygen concentration of combustion air reduces peak temperature of flame and increased air temperature makes flame stable by enhancement of combustion reaction. Special apparatus for recirculation of high temperature combustion gas should be needed, because general blower cannot be used to return the gas of almost 1,000℃. Air jet type recirculation apparatus has been developed and installed in a commercial scale of 7.2 ton/day incinerator and estimated. Oxygen concentration and temperature of air mixed with inhaled high temperature combustion gas by the apparatus are 16.24 ~ 17.78%, 384 ~ 512℃, respectively, in a steady state of incineration.

스테로이드를 투여 받는 환자에서 발생한 Nocardia farcinica 뇌 농양 1예

심성훈,박혜인조,김충종,전재현,김의종,오명돈,김남중,최강원 대한감염학회 2008 Infection and Chemotherapy Vol.40 No.5

Nocardiosis occurs mostly in the immunocompromised patients. N. farcinica is known to have resistance to some antibiotics and significant increase in morbidity and mortality in patients requiring long-term treatment. Nocardia farcinica infection, especially brain abscess, has not been reported in Korea. Here, we report a case of N. farcinica brain abscess in a patient receiving steroid treatment. The patient was a 64 year-old male with gouty arthritis. He received steroid for more than two months, because of allopurinol-hypersensitivity syndrome with skin rash. After three months of steroid therapy, he visited other hospital with mild fever and left thigh pain and was diagnosed of intramuscular abscess due to gram positive bacilli. One month later, he visited our hospital with right side weakness and was diagnosed as brain abscess. The causative organism turned out to be N. farcinica, which was confirmed by means of 16S rRNA sequencing. Antibiotics were selected by E-test results and treatment was successful.