칩브레이커 형상변수에 의한 칩유동각 예측

김동현,박승근,김경우 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.2

In machining with cutting tool inserts having complex chip groove shape, the flow, curl and breaking patterns of the chip are different than in flat-face type inserts. In the present work, an effort is made to understand the three basic phe-nomena occurring in a chip since its formation in machining with groove type and pattern type inserts. These are the ini-tial chip flow, the subsequent development of up and side curl and the final chip breaking due to the development of tor-sional and bending stresses. In this paper, chip flow angle in a groove type and pattern type insert is analyzed based on a force ratio method, involving the feed and radial forces in flat-face type, groove type and pattern type inserts. The expres-sion for chip flow angle in groove type and pattern type inserts is also verified experimentally using high speed filming techniques.

손가락 끝 점을 이용한 손 형상 인식

김종민,이웅기,장근실,양환석,허진경,박승규 朝鮮大學校 統計硏究所 2007 統計硏究所論文誌 Vol.9 No.1

최근 사용자 친화형 유저 인터페이스 구현을 위해 인간의 손 형상을 실시간으로 인식하는 연구의 중요성이 부각되고 있다. 그러나 인간의 손은 자유도가 크기 때문에 손 형상을 정확히 인식하기란 매우 어렵고 또한 피부색과 유사한 색을 가지는 복잡한 배경에서는 더욱 곤란하다. 본 논문에서는 별도의 센서를 부착하지 않고 카메라를 사용하여 피부색 정보에 의한 손 형상을 분할한 후 손가락 끝 점을 찾는다. 찾은 손가락 끝 점을 이용하여 방향을 탐지하는 알고리즘에 대해 기술한다. 이 방법은 템플리트 매칭을 이용하여 손가락 끝 점을 탐색한 후 찾은 손가락 끝 점과 손목의 중심을 이용하여 전, 후, 좌, 우 방향을 탐지한다. 제안하는 방법을 이용하여 3D 가상현실 공간에서의 네비게이션(Navigation)에 응용하였으며, 실험결과 전진, 후진 및 좌측, 우측의 방향전환도 매우 좋은 결과를 보였다. 또한 본 논문에서 제안하는 방법은 마우스, 키보드, 조이스틱 등의 조작 없이 전, 후, 좌, 우 방향전환을 사용자가 직관적으로 지시함으로써 보다 자연스러운 인간과 컴퓨터의 상호작용을 제공할 수 있을 것이다.

Agrobacterium을 이용한 치커리의 형질 전환

김대성,최근원,정인식,이승우 경희대학교식량자원개발연구소 2005 硏究論文集 Vol.24 No.-

본 실험은 치커리 'Radicchio'(Cichorium intybus L.)에서 Agrobacterium을 이용한 형질전환에 영향을 주는 요인들을 적정화하기 위하여 실시되었다. 치커리 'Radicchio'의 자엽절편체를 이용한 kanamycin과 cefotaxime 항생제 감응성 검정 결과 20 mg·L^(-1) 이상의 kanamycin 농도가 형질전환 신초의 선발에 적당하고 200 mg·L^(-1)의 cefotaxime 농도가 절편체 생장에 부정적인 영향을 주지 않으며 배지 내 Agrobacteria를 제거하기에 적절함을 나타내었다. Terpene cyclase 유전자가 재조합된 PILTAB 벡터를 갖는 Agrobacterium tumefaciens LBA4404와의 효과적인 공동배양 기간은 3일간으로 결정되었다. IAA 1.0 mg·L^(-1), BAP 1.0 mg·L^(-1), kanamycin 20 mg·L^(-1) 그리고 cefotaxime 200 mg·L^(-1)를 함유한 선발배지에서 형질전환 된 것으로 여겨지는 신초들이 생산되어 발근을 위해 kanamycin 40 mg·L^(-1)와 cefotaxime 200 mg·L^(-1)이 첨가된 1/2MS 발근배지에 옮겨져 87%의 발근율을 보였다. 발근된 형질전환체들을 대상으로 terpene cyclase 유전자특이 primer를 이용한 PCR 분석이 실시되어 재분화 치커리 내로 1.64 kb 크기의 terpene cyclase 유전자의 성공적인 도입을 확인하였다. This experiment was initiated to optimize factors affecting Agrobacterium-mediated transformation in Cichorium intybus L. cv. Radicchio. The results from the antibiotic sensitivity test for kanamycin and cefotaxime using cotyledon explants of chicory 'Radicchio' suggested that the concentration of kanamycin above 20 mg·L^(-1) might be an appropriate level to make a selection on transgenic shoots possible and 200 mg·L^(-1) of cefotaxime also could be a proper concentration to remove Agrobacteria from the media without any negative effect on explants. The efficient duration for co-cultivation of cotyledon explants with Agrobacterium tumefaciens LBA4404 harboring the recombinant binary vector PILTAB carrying 1.64 kb terpene cyclase gene was decided as 3 days. Putative transgenic shoots were produced on the selection media containing 1.0 mg·L^(-1) IAA, 1.0 mg·L^(-1) BAP, 20 mg·L^(-1) kanamycin, and 200 mg·L^(-1) cefotaxime and transferred to 1/2MS media supplemented with 40 mg·L^(-1) kanamycin and 200 mg·L^(-1) cefotaxime for rooting. The rooting ratio was 63% and putative transgenic plants with roots were obtained. Results from PCR analysis with terpene cyclase gene specific primers confirmed a successful insertion of 1.64 kb terpene cyclase gene into the genomic DNA of the regenerated chicory.

Narrow Band UVB로 치료한 진행성 반상 저색소증 1예

김병대,정예리,이근수,한승경 대한피부과학회 2003 대한피부과학회지 Vol.41 No.12

Progressive macular hypomelanosis is an idiopathic acquired hypopigmentary disorder first descri-bad in 1988. The disorder is characterized by ill-defined, non-scaly, round to oval, hypopigmented patches symmetrically localized on the trunk. No clinical symptoms have been observed. Currently, diagnosis is made on clinical grounds and any histological, laboratory investigations are not diagenositc. This disorder does not respond to conventional treatment and its clinical course is variable. We experienced a case of progressive macular hypomelanosis that was successfully treated with narrow band UVB phototherapy. (Korean J Dermatol 2003;41(12):1664~1666)

방사선 조사에 의한 흰주 난포의 퇴축과 난포세포의 방사선 감수성

김수일,한승로,조근자,허대영,이영호,조문준,김무강,김원식 충남대학교 의과대학 의학연구소 2002 충남의대잡지 Vol.29 No.1

The aim of this study were to investigate radiation-induced atresia and radiation susceptibility in the rat ovary morphologically. Female rats (Sprague Dawley strain) of 4 weeks old were irradiated with dose of 4 Gy and 8 Gy, and sacrificed at hour 6, 12, and 24 after radiation. The H & E stain, the TUNEL method (ApopTag kit) and transmission electron microscopy (TEM) were used. In light microscopic observation, the number of atresia of ovarian follicles were increased significantly at 6h after irradiation (p<0.01). There was no significant difference between 4 Gy and 8 Gy irradiated groups. In TEM observation, granulosa cells in radio-sensitive follicles were characterized by several structural features including condensation of nuclear chromatin granules, nuclear fragmentation and apoptotic body formation. An apoptotic cell is observed to have been phagocytosed by a normal granulosa cell. Granulosa cells in radio-resistant follicles were characterized by several structural features including nuclear indentation, partial condensation of chromatin granules, mitochondrial swelling, dilatation of RER cisterns, accumulation of dense irregular masses, accumulation of lipid droplets, and increased lysosomal bodies. Number of gap junctions between granulosa cells were decreased, and intercellular space were widen than that of control animals. These findings were prominent at 6h after irradiation and were diminished at 12h and 24h after irradiation. With these results, it was concluded that radiation-induced follicular cell apoptosis and ovarian follicular atresia in rat ovary increased considerably at 6h after irradiation. Further studies are needed to reveal the more extensive differences between radiosensitive and radioresistant follicular granulosa cells.

급성 B형 간염의 회복 후 말초혈액 단핵구에서의 HBV DNA검출

명승재,이영상,김형건,이근찬,박능화,정영화,서동진 大韓消化器病學會 1997 大韓消化器病學會誌 Vol.29 No.1

Acetonitrile 용액중에서 살충제 O,O-Dimethyl-O-(3-methyl-4-nitrophenyl)-phosphorothioate(Fenitrothion)의 전기화학적 환원에 대한 연구

金日光,金潤根,千賢子,朴勝熙 圓光大學校 基礎自然科學硏究所 1986 基礎科學硏究誌 Vol.5 No.2

The electrochemical reduction of o,o-dimethyl-o-(3-methyl-4-nitrophenyl)-phosphorothioate(fenitrothion)has been studied in acetonitrile solution containing surfactant micelle by direct current(DC)-differential pulse(DP) polarography, cyclic voltammetry(CV) and controlled potential coulometry(CPC). The totally quasiirreversible electron transfer-chemical reaction (EC, EC mechanism) of fenitrothion reduction proceeded by four electron transfer to form o,o-dimethyl-o-(3-methyl-4-hydroxyaminophenyl)-phosphorothiate which undergoes single bond of the phosphorus atom and phenoxy group cleaves to give p-hydorxyamino-m-cresol and dime-thyl thiophosphonate as major product by two electron transfer-protonation. The polarograpic reduction waves shown to be reversible adsorption current (-0.9 volts vs.Ag-AgCl) in sodium lauryl sulfate micelle solution and split up on selectivity of anionic micelle effect in two step at the first reduction peak.

차량의 방송 수신 전파 환경 분석에 관한 연구

김의태,김성철,이중근,양승완,전인학 漢陽大學校 工學技術硏究所 2001 工學技術論文集 Vol.10 No.-

본 논문에서는 이동 중인 차량의 수신 성능에 영향을 주는 전파 환경 측정을 위한 측정 셋업을 구성하고, 측정 결과 분석을 통한 수신 이상 현상의 원인을 밝혔다. 이를 위해 필요한 측정 파라메터의 정량적 설정과 측정 및 분석 방법을 제시하였다. In this paper we constitute the measurement setup of electromagnetic environment which has an effect on the radio receiver of vehicles an analyzed causes. This paper proposes various measurement and analysis methods for uncovering noise mechanism of vehicle receiver system.

흰쥐 난소에서 황체내 큰포식세포에 관한 형태학적 연구 : 면역조직화학적 및 투과전자현미경적 연구

김원식,한승로,조근자,김수일,박창식 충남대학교 형질전환복제돼지연구센터 2007 논문집 Vol. No.10

황체는 임신의 수립과 유지에 필수적인 일시적인 내분비샘으로, 주기능을 발정주기의 생리적 기간을 결정하고 성공적인 임신을 달성하는데 결정적인 프로게스테론의 생산이다. 황체의 기능은 뇌하수체 gonadotropin 뿐만 아니라 황체내 큰포식세포에서 분비되는 TNF-α를 포함한 몇가지 cytokines에 의해 조절되는 것으로 알려져 있다. 본 연구에서는 흰쥐 (Sprague-Dawley계통)에서 생식주기별 황체내 큰포식세포의 변화를 면역조직화학적 및 투과전자현미경적으로 관찰 비교하였다. 본 연구에서 흰쥐 황체에서 큰포식세포는 배란기,임신기 및 출산후기 등 모든 시기에 나타나고,그 수와 면역반응성은 배란기에 가장 컸고 출산후기,임신기 순으로 나타났다. 아울러 투과전자현미경 관찰에서는 황체내 큰포식세포를 세포체가 가늘고 돌기가 긴 비포식성 큰포식세포와 포식성 공포와 지방소체들을 많이 함유한 포식성 콘포식세포로 분류할 수 있었다. 본 연구를 통해 황체내 콘포식세포는 발정주기에 따라 그 수나 면역반응성이 다르며,황체퇴화가 활발히 진행되는 배란기와 출산후기에 면역반응성이 증가하고 포식성 큰식세포들이 나타난 것은 큰포식세포에서 TNF-α 와 같은 cytokines의 분비를 활발히 일으키고 그들이 황체세포들의 세포자멸사를 유발,촉진하고 또한 세포자멸 사소체들을 포식,제거하는 방법으로 황체퇴화를 유도하여 정상적인 발정주기를 유지하기 위한 기전으로 생각 되고,임신기에 큰 포식세포의 수와 면역반응성이 작아지고 비포식성 큰포식세포가 주를 이루는 것은 이들이 TNF-α 동의 cytokines 분비를 통해 그들이 황체자극효과를 나타내 황체의 기능을 유지,촉진하는데만 관여하고,한편으로는 황체에서 생산되는 프로게스테론에 의한 큰포식세포 억제작용 때문인 것으로 생각된다. Macrophages in the corpus luteum have many important roles during the periods of functional development and luteal regression. Not only phagocyte the apoptotic luteal cells, but also they secrete many cytokines and exert their effects via autocrine/paracrine actions. In this study, we investigated the changes of number and immunoreactivity of macrophages at various developmental periods of the corpus luteum in the rat ovary. The rats (Sprague- Dawley strain, female) at age of 8 weeks (ovulatory period), GD 6 (pregnant period), and postpartum 5 days (postpartum period) were sacrificed under ether anesthesia and obtained both ovaries, one used for macrophages immunohistochemistry and the other used for TEM. The results were as follows; I. In the corpora lutea of the rat, macrophages were observed all the developmental periods including ovulatory, pregnant and postpartum periods. 2. In the corpora lutea of the rat, number of macrophages was highest in the ovulatory period, and decreased at postpartum period and pregnant period in order. The immunoreactivity of macrophages was high at ovulatory period, moderate at postpartum period, and low at pregnant period. 3. In TEM observations, two types of macro phages were observed: One type was non-phagocytic macrophage and the other type was phagocytic macrophage. Phagocytic macrophages were observed in the corpora lutea at ovulatory and postpartum periods and contained apoptotic bodies, phagocytic vacuoles and many lipid droplets. Non-phagocytic macrophages were observed in the corpora lutea at pregnancy period and showed slender cell body with long cytoplasmic processes and contained no apoptotic bodies. In the rat, the number and the degree of immunoreactivity of macrophages in the corpus luteum varied with the changes of functional state of the corpus luteum. It was suggested that the main function of the macrophages at the ovulatory and postpartum periods was elimination of apoptotic luteal cells and that at pregnancy period was autocrine/paracrine action. Ultrastructurally, two types, phagocytic and nonphagocytic types, of macrophages confirmed. These results will provide valuable informations on the study of the role macrophages during development and regression of corpus luteum.

한번의 간질발작 후 혈청 Neuron-Specific Enolase 농도 변화

최승호,박영춘,이장준,임정근,김지언,이상도 啓明大學校 醫科大學 1999 계명의대학술지 Vol.18 No.4

An increase in neuron-specific enolase (NSE) levels in serum and CSF has been shown to be an useful marker of brain damage after stroke, global ischemia, and coma. We report the changes of serum NSE levels after seizure attacks in epileptic patients compared with the levels in normal controls and epileptic patients without seizure attack at least 7 days (epileptic controls). Twenty-four seizures were included in this study. Blood was drawn within 1 hour, at 12 hour, 24 hour, and 48 hour after seizure attack. Serum NSE levels were measured with radioimmunoassay. The mean NSE levels for normal controls and epileptic controls were 6.94 ng/ml and 7.46 ng/ml, respectively. There were significant increase in level of serum NSE measured within 1 hour after seizure attack in epileptics compared with the level in normal controls (15.10ng/ml versus 6.94ng/ml, p<0.05) and epileptic controls (15.10ng/ml versus 7.46ng/ml, p<0.05). Serum NSE measured at 12 hours after seizure also increased compared with normal controls (12.32ng/ml versus 6.94ng/ml, p<0.05) and epileptic controls (12.43ng/ml versus 7.46ng/ml, p<0.05). Between normal controls and epileptic controls, there were no significant difference in serum NSE levels. We conclude that serum NSE level was elevated in epileptic patients who had seizure attack within 12 hours. Serum NSE levels can be useful marker for seizure within 12 hours after onser. The elevated serum NSE level after single seizure attack may suggest that the brain was injured in single seizure.