펄스 옥시미터의 동잡음 제거 필터 설계

김도영,김일환 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.A

Pulse oximetry, which monitors non-invasively the oxygen saturation in blood, is influenced by patient's respiration, movement or a factor of an environment. Specially, it's difficult to measure a PPG (Photoplethsmography) signal from the moving patient because of the motion artifact. Accordingly, it is required to extract the pure PPG signal from the PPG signal to measure oxygen saturation. In this paper, we propose an adaptive noise canceller to improve the performance of motion artifact removal. Then we design a hardware system for real time monitoring of the oxygen saturation. The proposed algorithm estimates the slope of transition rate between two different wavelength signals.

용접비드 형상예측 시스템 개발에 관한 연구

김일수,손준식,박창언,서주환,장경천,이동길 朝鮮大學校 機械技術硏究所 2005 機械技術硏究 Vol.8 No.2

Generally, the use of robots in manufacturing industry has been increased during the past decade. GMA(Gas Metal Arc) welding is an actively growing area and many new procedures have been developed for use with high strength alloys. One of the basic requirement for welding applications is to study relationships between process parameters and bead geometry. The objective of this paper is to develop a new approach involving the use of neural network and multiple regression methods in the prediction of bead geometry for GMA welding process and to develop an intelligent system that enables the prediction of bead geometry using Rapid Prototyping(RP) in order to employ the robotic GMA welding processes. This system developed using MATLAB/SIMULINK, could be effectively implemented not only for estimating bead geometry, but also employed to monitor and control the bead geometry in real time

펄스 옥시미터의 동잡음 제거 필터 설계

김도영,김일환 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.B

Pulse oximetry, which monitors non-invasively the oxygen saturation in blood, is influenced by patient's respiration, movement or a factor of an environment. Specially, it's difficult to measure a PPG (Photoplethsmography) signal from the moving patient because of the motion artifact. Accordingly, it is required to extract the pure PPG signal from the PPG signal to measure oxygen saturation. In this paper, we propose an adaptive noise canceller to improve the performance of motion artifact removal. Then we design a hardware system for real time monitoring of the oxygen saturation. The proposed algorithm estimates the slope of transition rate between two different wavelength signals.

호안단면의 안정성 검토에 관한 연구

민일규,이정환,민병형,김창동 東亞大學校 海洋資源硏究所 1998 硏究論文集 Vol.11 No.1

The necessity of development of the Nearshore zone and land reclamation has greatly emphasis in resent years. In this study, I investigated on the overtopping in the frontside of the reclamation and distance from revetment when dredging operations. Obtained results are summarized as follows. 1. In the result of the wave deformation model application, a significant wave height is 1.0m at reclamation the front revetment. 2. Experiment result of revetment section overtopping is in the permitted range of HUKUDA. 3. In the purpose of decision safety of revetment, I have been discovered the highest effect at 25m∼40m distance.

신경회로망을 이용한 이면비드 폭 예측에 관한 연구

정재원,김일수,박창언,김학형,서주환,김인주,심지연 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

The development of robotic welding process is a very complex assignment because the system is affected by a number of process parameters which are very difficult to determine or predict in practice. The full automation welding has not yet been achieved partly because the mathematical model for the process parameters of a given welding task is not fully understood and quantified. Several mathematical models to control welding quality, Productivity, micro structure and weld properties in arc welding processed have been studied. However, it is not an easy task to apply them to the various practical situations because the relationship between the process parameters and the bead geometry is non-linear and also they are usually dependent on specific experimental result. Practically, it is difficult, but important to know how to establish a mathematical model that can predict the result of the actual welding process and how to select the optimum welding condition under a certain constraint. In this paper, an attempt has been made to develop an neural network model to predict the back-bead width as a function of key process parameters in the GMA (Gas Metal Arc) welding and to compare the developed models with the experimental results

위의 유암종과 선종의 병발 1례

장재식,강혁주,이중현,서영범,윤병구,김용섭,이구,서정일,양창헌,이창우,김정란,윤환중 東國大學校醫學硏究所 2000 東國醫學 Vol.7 No.-

유암종은 전신에 퍼져 잇는 장크롬친화성 세포에서 기원하는데 위의 유암종은 비교적 드문 질환으로 모든 유암종의 1.9~2.2%에 해당하며 위에 발생하는 종양의 1% 미만에서 보고되고 있다. 유암종은 일반적으로 증상이 비특이적이고 면역조직화학검사에 의해서 진단되기 때문에 과거에는 드물게 발견되었으나 최근 내시경 기기 및 술기의 발전과 검사 빈도의 증가 및 면역조직화학검사의 발달로 진단율이 증가 추세에 있으며, 드물지만 유암종에서 선암과 공존하는 예들이 보고되고 있다. 저자들은 심와부 동통을 주소로 내원한 70세 남자 환자의 상부위장관내시경 검사에서 위체상부의 대만곡에서 0.4×0.4 cm 크기의 중간 함몰을 가진 Yamada 1형의 용종과 함께 전정부의 전벽에서 0.8×0.5 cm 크기의 융기된 점막 소견을 보여 조직학적으로 각각 위유암종 및 위선종임을 확진한 후 내시경적 용종 절제술로 치료한 1예를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Carcinoid tumors are arisen from enterochromaffin cells, which are scattered throughout the body. These tumors are composed of variable numbers of cells that contain endocrine granules in their cytoplasm, which can be identified by immunohistochemistry and electron microscopy. Gastric carcinoid tumors are relatively rare tumor, the reported incidence being 1.9~2.2% of all carcinoid tumors and less than 1% of all gastric tumors. Sometimes, composite carcinoid tumors and adenocarcinoma is reported. We experienced a case of the coincidence of carcinoid tumor and adenoma at the other site of the stomach in a 70 year old male patient. Gastrofiberscope showed 0.4×0.4 cm sized Yamada type I polyp with central depression on the greater curvature of the proximal body and 0.8×0.5 cm sized focal slightly elevated mucosa on the anterior wall of the antrum. The endoscopic biopsy specimens revealed carcinoid tumor and tubular adenoma with moderate atypism, respectively. The carcinoid tumor and adenoma were removed by endoscopic polypectomy. According to the follow-up gastrofiberoscopy after 7 month later, both lesions were nearly normal mucosa except whitish atrophic change after polypectomy.

The Characteristics of CIGS Thin-Film Solar Cells Using Sputtering Based Two-Step Process

Young-Ill Kim,Dong-Hwan Jeon,Si-Nae Park,Se-Yun Kim,Dae-Hwan Kim,Jin-Kyu Kang,Shi-Joon Sung,Juran Kim,William Jo,Hyesun Yoo,JunHo Kim,Dae-Hwan Kim,Kee-Jeong Yang 한국신재생에너지학회 2019 AFORE Vol.2019 No.11

Void and secondary phase formation mechanisms of CZTSSe using Sn/Cu/Zn/Mo stacked elemental precursors

Kim, Se-Yun,Son, Dae-Ho,Kim, Young-Ill,Kim, Seung-Hyun,Kim, Sammi,Ahn, Kwangseok,Sung, Shi-Joon,Hwang, Dae-Kue,Yang, Kee-Jeong,Kang, Jin-Kyu,Kim, Dae-Hwan Elsevier 2019 Nano energy Vol.59 No.-

<P><B>Abstract</B></P> <P>In recent years, Cu<SUB>2</SUB>ZnSn(S<SUB>1-x</SUB>Se<SUB>x</SUB>)<SUB>4</SUB> (CZTSSe) prepared by a two-step process using metal precursors has been reported to exhibit a relatively high power conversion efficiency, and a high efficiency of 12.5% by two-step process contained via sputtering method was recently confirmed by our group. In this study, we proposed formation mechanisms for the CZTSSe double layer, voids and ZnSSe layer, which were observed in the CZTSSe using metal precursor. Due to the persistent dezincification from the metal precursors and preferential reaction between the Zn and chalcogens such as S and Se, almost all Zn is consumed to form the ZnSSe layer; as a result, large voids are produced first under the ZnSSe layer. Cu<SUB>2</SUB>Se and SnSe are grown on the ZnSSe layer via migration of the Cu and Sn through the grain boundaries of the ZnSSe layer. Thus, additional small voids are expected to form due to the mass transfer of Cu and Sn. Because of the preferentially formed ZnSSe layer and the chalcogenation of Cu and Sn after the mass transfer, a CZTSSe double layer can be formed, and ZnSSe can exist between these CZTSSe layers. Finally, we propose a method based on the formation mechanism to control the voids and secondary phases, which affect the fill factor and output current.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The new formation mechanisms of the voids, ZnSSe layer and CZTSSe double layer that were observed in the sister sample of 12.5% of CZTSSe cell. </LI> <LI> Large voids are produced under the ZnSSe layer due to the persistent dezincification and preferential reaction between the Zn and chalcogens. </LI> <LI> Additional small voids are expected to form due to the migration of Cu and Sn from under the ZnSSe layer to above ZnSSe layer. </LI> <LI> Due to the preferentially formed ZnSSe layer and Cu and Sn migration, ZnSSe secondary phase exists between the CZTSSe double layers. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The new formation mechanisms of the voids, ZnSSe layer and CZTSSe double layer that were observed in the sister sample of 12.5% of CZTSSe cell.</P> <P>[DISPLAY OMISSION]</P>

지구성 운동이 흰쥐 해마에서 산화질소합성효소 발현에 미치는 영향

김영표,윤진환,정일규,최덕구,이계영,김성수,신말순,김창주 한국운동과학회 2002 운동과학 Vol.11 No.2

김영표, 윤진환, 정일규, 최덕구, 이계영, 김성수, 신말순 김창주. 지구성 운동이 흰쥐 해마에서 산화질소합성효소 발현에 미치는 영향. 운동과학, 제11권 제2호, 359-370, 2002. 본 연구는 지구성 운동이 해마 치상회(hippocampal dentate gyrus)에서 nitric oxide (NO)의 합성효소인 nitric oxide synthase (NOS) 발현에 미치는 영향을 규명하기 위하여 Sprague-Dawley계 수컷 흰쥐 총24마리를 대조군 (n = 8), 저강도 운동군 (n = 8), 중등도 운동군 (n = 8)으로 분류하여, 일일 1회, 1주일에 5일간 총 4주 동안 트레드밀 지구성 운동을 실시하였다. 저강도 운동군은 트레드밀 경사도 0 %에서 처음 5분간 3 m/min, 다음 5분간 5 m/min,그리고 20분간 8 m/min 속도로 총 30분 달리기를 실시하였으며, 중등도 운동군온 초기 5분간 16 m/min, 다음 5분간 19 m/min, 그리고 20분간 22 m/min 속도로 달리기를 실시하였다. NOS 양성세포수 발현을 관찰하기 위하여 nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) 조직화학법을 실시하였다. 체중의 변화는 모든 군에서 4주 후에 유의하게 증가하였고 중등도 운동군은 운동 1주와 운동 2주 후에 대조군과 저강도 운동군에 비해 체중의 증가가 유의하게 낮았으며, 운동 4주 후에는 대조군보다 체중의 증가가 유의하게 낮게 나타났다. 해마 치상회 (dentate gyrus) 부위에서 지구성 운동에 의한NADPH-d 양성세포 수 발현은 집단간 유의 (p<.001)한 차이를 보였으며, 사후검점 결과 중등도 운동군은 대조군과 저강도 운동군보다 NOS의 발현이 유의하게 낮게 나타났다. 해마 CA1 부위에서 생성된 NADPH-d 양성세포 수는 집단간 유의(p<.01)한 차이를 보였으며, 사후검정 결과 중등도 운동군은 대조군과 저강도 운동군보다 NOS의 발현이 유의하게 낮게 나타났다. 해마 CA2와 CA3 부위에서 생성된 NADPH-d 양성세포 수는 집단간 유의(p<.001)한 차이를 보였으며, 사후검정 결과 중등도 운동군은 대조군과 저강도 운동군보다 NOS의 발현이 유의하게 낮게 나타났다. 본 실험의 결과 장기간 지구성 운동은 해마의 치상회, CA1 부위, 그리고 CA2와 CA3 부위에서 NOS의 발현을 감소시켰으며, 이러한 NOS 발현의 감소는 병적인 상태시 급격한 NO의 증가를 억제함으로써 세포 손상을 방지할 수 있을 것으로 생각되어진다. Kim, Y.P., Yoon, J.H., Jeong, I.G., Choi, D.G., Lee, G.Y., Kim S.S., Shin, M.S., Kim, C.J., Effect of endurance exercise on nitric oxide synthase expression in hippocampus of rats. Exercise Science 11(2): 359-370, 2002. The effect of endurance exercise on nitric oxide synthase expression in the dentate gyrus, CA1, CA2 and CA3 of the hippocampus was investigated via nicotinamide adenine dinudeotide phosphate -diaphorase (NADPH-d) histochemistry. Male Sprague -Dawley rats were randomly divided into the three groups: the control group, the low-intensity exercise group, the moderate-intensity exercise group n=8 in each group. Animals of the exercise groups were put on running for 30min once a day, 5 days per week for 4 weeks. The regimen of the low-intensity exercise consisted with running at speed of 3 m/min for the first 5 min, 5 m/min for the next 5 min, then 8 m/min for the last 20 min, while the regimen for the moderate-intensity exercise was made with running at speed of 16 m/min for the first 5 min, 19 m/min for the next 5 min, then 22 m/min for the last 20 min. In the present results, weight gain of the rats in the moderate-intensity exercise group was significantly decreased compared to the control group and mild-intensity exercise group. In the moderate-exercise intensity group, NOS expression was significantly than lower the control and low-intensity exercise group in the dentate gyrus (p<.001), CA1 (p<.01), CA2 and CA3 (p<.001). It can be suggested that endurance exercise may prevent cell damage by inhibiting NOS expression of hippocampus.

WAFER-LEVEL ALIGNED BONDING OF GLASS-PDMS-GLASS FOR OPTICS APPLICATION

Ill hwan Kim,Hyeon Cheol Kim,Kukjin Chun 대한전자공학회 2007 ITC-CSCC :International Technical Conference on Ci Vol.2007 No.7