• Journal of the korean Society of Automotive Engineers
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• v.15 no.6
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• pp.14-22
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• 1993

본 글에서는 자동차엔진을 모형화한 정적연소기내의 라디칼 계측기술에 관해 언급하고자 한다. 밀폐연소기내에서 연소반응에 의해 발생된 국소 및 평균 라디칼 강도를 계측하여 순간당량비를 구할 수 있는 관계식을 유도할 수 있으며, 이것을 이용하면 기관에서 발생되는 연소과잉에 의하여 순간당량비를 구하거나, 각종 산업용 버너 등 다양한 연소기에 적용할 수 있을 것이다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.5
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• pp.365-372
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• 2009

The influence of combustor pressure on the local reaction characteristics of $CH_4$/air flames was investigated by measurements of local chemiluminescence intensity. Induced flow flames are often applied to the industrial boiler systems and incinerator in order to improve heat transfer and prevent exhaust gas leakage. In order to investigate combustion characteristics in the induced flow pattern, the combustor pressure index($P^*$) was controlled in the range of $0.7{\sim}1.3$ for each equivalence ratio in the present combustion system, where $P^*$ is defined as the ratio of absolute pressure to atmospheric one. Relationship between local reaction intensity and pressure index have been investigated by simultaneous $CH^*$, $C^*_2$ and $OH^*$ intensity measurements. It could be observed that flame length became longer with decreasing $P^*$ from $CH^*$ chemiluminescence intensity of axial direction. The mean value of $C^*_2$ and $CH^*$ chemiluminescence intensities, which indicates reaction intensity in the $CH_4$/air flames, decreased with decreasing pressure index for ${\Phi}{\leq}1$, but increased with decreasing pressure index for ${\Phi}$>1. $C^*_2/CH^*$ intensity ratio, which can be a good marker to demonstrate local equivalence ratio, was almost same for ${\Phi}{\leq}1$ regardless of pressure index change, while they showed high level for lower pressure index for ${\Phi}$>1 conditions.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2516-2518
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• 2003

본 논문은 고차 뉴런의 문제점으로 지적되고 있는 뉴런이 방대하게 증가하는 문제를 해결하고자, 최적의 뉴런을 생성하고 생성되어진 고차 뉴런 중 일정 비율로 뉴런의 연결강도를 도태시켜 감에 따라 네트워크상에 나타나는 특성을 비교하였다. 본 논문은 고차 뉴런을 이용한 Kohonen의 자기 조직화 맵의 고차 뉴런부에 일정 비율로 연결강도를 도태한 후 인식률을 얻는 형태로 시뮬레이션을 하였다. 특히, 종래 형태의 고차 뉴런을 이용한 Kohonen 자기 조직화 맵의 알고리즘을 변형없이 사용하였으며 중복되는 뉴런을 최대한 억제하기 위해 2차 뉴런만을 생성한 네트워크 구조 위에 입력 데이터의 특징을 유지하고 고차 뉴런의 특징을 더욱 활성화하기 위해 일정한 양의 연결강도를 도태시킴으로써 출력면에서 국소집중 반응에 의한 정확한 인식률 향상 등을 조사하는 시뮬레이션을 하였다. 본 제안 모델의 특성을 살펴보기 위해 60개의 데이터로 이루어진 금속 소나 음데이터와 암석 소나 음 데이터를 이용하여 금속인지 암석인지를 판별하는 시뮬레이션을 하였다.

• Journal of Energy Engineering
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• v.9 no.2
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• pp.146-155
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• 2000

연료분출을 수반하는 원통형 보염기 후류에 형성되는 확산화염에 대한 이온전류의 특성과 화염의 안정범위를 측정, 분석함으로써 연소특성을 고찰하였다. 난류강도가 큰 경우의 화염일수록 화염의 안정성은 악화되며, 화염내 중앙의 평균 이온전류값이 가장 높은 값을 갖는 영역은 블로오프 직전상태에 비해서 안정시의 경우 더욱 하류측에 존재한다. 난류의 정도가 강한 화염의 경우 국소적으로 반응이 활발한 화염 덩어리가 빠른 속도로 이동하며, 난류의 정도가 강한 화염의 경우에는 반응이 완만한 화염 덩어리가 저속으로 이동한다. 재순환영역에서 주류유동측으로 이동함에 따라 자기상관계수의 저하가 빨라지고 난류 시간스케일이 작아지며, 부염기 직후에서 하류로 이동함에 따라 자기상관계수의 저하가 늦어지고 난류시간스케일이 커진다. 주류공기에 강한 난류를 가하지 않은 경우에는 큰 난류시간스케일에 대응되는 저주파수 특성이외에도 작은 난류 시간스케일에 대응되는 고주파수 특성이 나타나며 , 주류공기에 강한 난류를 가한 경우에는 큰 난류 시간스케일에 대응되는 저주파수 특성이 나타난다.

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.953-964
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• 1999

본 연구는 세 종류의 Porphyromonas gingivalis(Pg) antigen의 IgG subclass associated recognition을 평가하기 위해 수행했었다. 총 35명의 조기발병형치주질환자중, Pg381에 대한 IgG2항체의 증가를 보이는 5명이 급속진 행형 치주질환자, IgG4의 증가를 보이는 6명의 환자(국소유년형 치주질환자 2명과 급속진행 형 치주질환자 4명), IgG2+4의 증가를 보이는 2명의 급속진행형 치주질환자 그리고 IgG1+2+4의 증가를 보이는 8명의 환자(국소 유년형 치주질환자 2명과 급속진행형 치주질환자 6명)으로 구성된 21명의 환자를 dot immunoblot analysis를 위해 선택했다. 실험에 사용된 정제된 항원은 Pg381에서 추출한 43-kd fimbrilin protein과 lipoplysaccharide(LPS), Pg A7A1-28(ATCC 53977)에서 추출한 capsularpolysaccharide(CPS)였다. Immunoblotting pattern은 IgG4 antibody가 fimbrial antigen에 강력히 반응함을 보여주었다. Fimbriae에 잘 반응하는 몇몇의 IgG4 antibody역시 antigen에 대해 양성반응을 보였다. 대조적으로 IgG2는 CPS antigen을 일차적으로 인식했다. 전부는 아니지만 대부분의 경우, single이나 group화된 IgG subclass는 모두 LPS antigen을 인식하지 못했다. 같은 group에서 염색강도의 개인적인 차이는 증명되었다. 이런 결과는 조기발 병형 치주질환에서 Pg의 fimbriae와 CPS가 immunodominant antigen이 될 수 있음을 제시한다. 더욱이 IgG subclass antibody가 이런 Pg의 immunoglobulin antigen을 선택적으로 인식함을 알았고, 이는 조기발병형치주질환의 병리에 immunodominant antigen과 함께 IgG의 기능적인 역할을 고려해야 함을 제시한다.

• Journal of the Korean Society of Radiology
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• v.81 no.1
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• pp.190-196
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• 2020

Xanthogranulomatous inflammation is a rare inflammatory reaction, characterized by lipid-laden macrophages, known as xanthomas, in histopathologic examination. Aggressive xanthogranulomatous inflammation often manifests as local infiltration but does not affect distant organs unless combined with rare systemic diseases. We report a case of focal xanthogranulomatous pyelonephritis (XGP) associated with severe xanthogranulomatous cholecystitis. Focal XGP was suspected in radiologic examination that showed a cystic lesion with an infiltrative margin, which were surgically resected and confirmed in pathologic examination. To our knowledge, this is the first report of focal xanthogranulomatous pyelonephritis associated with xanthogranulomatous cholecystitis. Moreover, we found peripheral hypointensity around the cystic lesion in the T2-weighted image, probably reflecting hemorrhage and fibrosis of the xanthogranulomatous inflammation.

• The korean journal of orthodontics
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• v.34 no.4 s.105
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• pp.343-349
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• 2004

Laser-aided debonding has advantages in that the heat produced is localized and controlled, the debonding tool is not heated, and it can be used for the removal of various types of ceramic brackets, regardless of their design. However, the range of safe power usage for laser-aided debonding has not vet been confirmed. The Purpose of this study was to evaluate the histologic changes of pulpal tissue in a rabbit's incisor after Nd-YAG laser-aided ceramic bracket debonding at different levels of power. The result were as follows: 1. At 3-5W Nd-YAG laser power level and 3 seconds of exposure time, the ceramic bracket debonding procedure was not easy. At 5W of power a tie-wing fracture occurred on one bracket during debonding using Weingart plier. The histologic section of pulp represented no adverse changes. 2. At 7-13 W power level and less than 5 seconds of exposure time, the debracketing procedure was done easily and bracket facture did not occur. The histologic section of pulp represented mild and reversible changes. All the results were reversible and no pulpal degeneration or necrosis occurred. Considering the results, it appears that the laser-aided debonding technique is a safe method that does not result in irreversible pulpal changes, softens bracket bonding resin within a saie range of power and exposure time, and is useful for ceramic bracket recycling by lowering the tie- wing fracture rate.

• Parasites, Hosts and Diseases
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• v.36 no.2
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• pp.109-120
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• 1998

Mucosal mast cell (MMC) and goblet cell (GC) responses were observed in the small intestine of two strains of mice (BALBfc and C3H) infected with Weodiplostomum seouLehTe, and their roles in the host defense and worm expulsion were studied. From day 3 to 28 post-infection (Pl) with 200 metacercariae, the worm recovery rate from BALB/c mice was consistently and remarkably higher than that from C3H mice. In the duodenum of both strains of mice, the main habitat of the flukes, mastocytosis was pronounced on day 7 Pl but quickly diminished thereafter. Similar kinetics were observed in the jejunum and ileum, although the extent of mastocytosis was lesser in the ileum than other two areas. These MMC kinetics were not different between the ko strains of mice. Moreover, the extent of mastocytosis was stronger in BALB/C mice than in C3H mice. GC hyperplasia was remarkable in the duodenum of BALBlc mice throughout the course of infection except day 14 Pl, whereas it was recognizable only in the jejunum and ileum of C3H mice on day 7 Pl. Mucin activation was evidently demonstrated in both strains of mice throughout the course of infection, but more marked in BALB/c than in C3H mice. The results strongly suggest that mastocytosis and GC hyperplasia are local immune responses against N. seoulense, however, they play a minor role in the host defense and worm expulsion.

• Journal of the Korean Society of Combustion
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• v.14 no.4
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• pp.41-47
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• 2009

An experimental study was performed to confirm the effect of the changing combustor pressure(-30~30 kpa), combustion characteristics were investigated by measuring the local chemiluminescence intensity, the local temperature distribution and emission. In order to investigate combustion ones, the combustor pressure index($P^*$) was controlled in the range of 0.7~1.3 for each equivalence ratio in the present combustion system, where $P^*$ is defined as the ratio of absolute pressure to atmospheric one. The local mean temperature showed the uniform distributions for lower pressure index, which increased with increasing equivalence ratio. The mean $OH^*$ chemiluminescence intensity, showed high level for lower pressure index for ${\Phi}{\get}1.0$ conditions. EINOx decreased with decreasing pressure index for overall equivalence ratio conditions.

• Radiation Oncology Journal
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• v.28 no.3
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• pp.133-140
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• 2010

Purpose: We retrospectively investigated the effect of irradiation using helical tomotherapy in recurrent pelvic tumors that underwent prior irradiation. Materials and Methods: Fourteen patients with recurrent pelvic tumors consisting of rectal cancer (57.1%), cervical cancer (35.7%) and cancer with an unknown origin (7.1%) were treated with tomotherapy. At the time of irradiation, median tumor size was 3.5 cm and 7 patients complained of pain originating from a recurrent tumor. The median radiation dose delivered to the gross tumor volume, clinical target volume, and planning target volume was 50 Gy, 47.8 Gy and 45 Gy, respectively and delivered at 5 fractions per week over the course of 4 to 5 weeks. Treatment response and duration of local disease control were evaluated using the Response Evaluation Criteria in Solid Tumors (ver. 1.0) and the Kaplan-Meyer method. Treatment-related toxicities were assessed through Common Terminology Criteria for Adverse Events (ver. 3.0). Results: The median follow-up time was 17.3 months, while the response rate was 64.3%. Symptomatic improvement appeared in 6 patients (85.7%). The median duration time of local disease control was 25.8 months. The rates of local failure, distant failure, and synchronous local and distant failure were 57.1%, 21.4%, and 7.1%, respectively. Acute toxicities were limited in grade I or II toxicities, except for one patient. No treatment related death or late toxicity was observed. Conclusion: Helical tomotherapy could be suggested as a feasible palliative option in recurrent pelvic tumors with prior radiotherapy. However, to increase treatment effect and overcome the limitation of this outcome, a large clinical study should be performed.