Park's Vector 기법을 이용한 소형 3상 유도 전동기의 권선 고장 진단

한민관(Min-kwan Han),우혁재(Hyeok-jae Woo),송명현(Myung-hyun Song),박규남(Kyu-nam Park) 대한전기학회 2003 대한전기학회 학술대회 논문집 Vol.2003 No.7

Park's 벡터 패턴의 왜곡률을 이용한 고정자 권선 고장 자동진단

宋明現(Myung-Hyun Song),朴奎南(Kyu-Nam Park),韓東奇(Dong-Gi Han),梁哲午(Chul-Oh Yang) 대한전기학회 2008 전기학회논문지 P Vol.57 No.2

In this paper, an auto-diagnosis method of the stator winding fault for small induction motor is suggested. 3-phase stator currents are sampled, filtered, and transformed with Park's vector transformation. After then Park's vector patterns are obtained. To detect the stator winding fault automatically, a distortion ratio is newly defined and compared with the one of healthy motor, and the threshold levels of distortion ratio are suggested. The 2-turn, 4-tum, 8-turn winding fault are tested with no load, 25%, 50%, 75%, and 100% rated load. The distortion ratio of the Park's vector patterns are increased as the increase of the faulted turns. but are same as the increase of the load.

Effects of Pilger Rolling and Heat Treatment on Microstructure and Corrosion Resistance of Ag-electroplated 304 Stainless Steel Tubes

Hyun Park,Woo‑Jin Lee,Jae‑Han Son,Han‑Kyun Shin,Sung‑Kyu Hong,Hyo‑Jong Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

We introduce a cost-effective method that combines electroplating with metal cold working processes to manufacture compositetubes with robust corrosion resistance. First, a 3-step electroplating process was developed to form an adhesive anduniform Ag coating on the outer wall of a 304 stainless steel tube. The process consisted of a Ni-strike step for removing thepassivation layer of the initial 304 tube, Cu deposition for smoothing the surface by adding a buffer layer, and Ag deposition. To reinforce the interfacial adhesion between the electroplated layers and the 304 tube and increase the area of the Ag coating,a pilger rolling or pilger rolling + heat-treatment process was performed after the Ag electroplating process. Scanningelectron microscopy of the composite tubes after each process indicated that the as-deposited Ag coating changed fromhaving a rough to smooth surface after only pilger rolling and with additional heat treatment. Electron backscatter diffractionanalysis of the microstructures and textures of the tubes revealed that dynamic recrystallization occurred extensively duringpilger rolling, resulting in the formation of a relatively defect-free grain structure without heat treatment. Furthermore,electrochemical polarization curves determined that the Ag-coated composite tubes are superior to the uncoated 304 tubein terms of corrosion resistance under Cl−atmosphere, owing to the formation of a AgCl passivation layer during testing. Surface analysis of the composite tubes suggests that the properties of the AgCl passivation layer are related to the grainsize of the Ag coating and the density of plastic-deformation-induced defects.

고관절 반 치환술의 대퇴 골절 예방을 위한 강선 고정의 효과

유정한 ( Jeong Han Yoo ),박용욱 ( Yong Wook Park ),박진수 ( Jin Soo Park ),노규철 ( Kyu Cheol Rowe ),정국진 ( Kuk Jin Chung ),김홍균 ( Hong Kyun Kim ),김형년 ( Hyong Nyun Kim ),임희준 ( Hee Joon Lim ),이철 ( Cheol Lee ),황지효 ( 대한고관절학회 2009 Hip and Pelvis Vol.21 No.2

목적: 무시멘트형 양극성 반 인공 관절 치환술에 있어서 수술 도중 발생하는 대퇴 골절 예방을 위한 예방적 강선 고정술의 효과를 분석하고자 한다. 대상 및 방법: 2004년 1월부터 2008년 8월까지 무시멘트형 양극 인공 관절 치환술을 받은 65세 이상의 환자 48명(1군)을 대상으로 하여 강선을 사용하지 않은 48명의 환자(2군)와 비교하였다. 평균 나이는 75.4세(1), 73.6세(2)이었고 평균 추시 기간은 19.1개월(1), 18.3개월(2)이었다. 수술 도중 골절 발생율 외에 수술 시간, 수술 도중 예상 출혈량, 입원 기간, 방사선학적 안정성을 측정하였고 임상적 평가를 위한 대퇴 통증과 Jensen의 기능 점수와 Parker와 Palmer의 활동 점수를 비교하였다. 결과: 1군에서는 수술 도중 골절이 발생하지 않았으며 2군에서 4예(8.3%)가 발생하였다(p=0.041). 수술 시간은 각각 172분(1), 162분(2) 예상 출혈량은 866 cc(1), 855 cc(2), 입원기간 36일(1), 35일(2)이었다. 방사선학적으로 침강은 1.59 mm(1), 1.67 mm(2)이었으며 임상적으로 대퇴 통증이 1예(1), 2예(2) 관찰되었다. 임상적으로 Jensen의 기능 점수는 평균 2점(1) 2.2점(2), Parke와 Palmer의 활동 점수는 평균 5.2점(1), 5.3점 (2)이었다. 결론: 무시멘트형 인공 관절 치환술에 있어서 예방적 강선 고정술은 골절률을 의의있게 감소시켰다. Purpose: The purpose of this study was to assess the effect of a prophylactic cable fixation for prevention of femoral fractures in cementless bipolar hemiarthoplasties. Materials and Methods: Forty-eight cementless bipolar hemiarthroplasties with prophylactic cable fixations on the femur were performed in patients>65 years of age between January 2004 and August 2008 (group 1). The control group which did not undergo prophylactic cable fixation included 48 cases (group 2). The mean age was 75.4 years (group 1) and 73.6 years (group 2). The patients were followed up for an average of 19.1 (group 1) and 18.3 months (group 2). The intra-operative fracture rates were compared. Additionally, operative time, estimated blood loss (EBL), and length of hospital stay were compared. Radiologic assessment for stem stability was performed. Clinical assessment was evaluated by the thigh pain and Jensen`s functional score, and Parker & Palmer`s mobility score. Results: There was no fractures in the cabled group (1), and 4 fractures (8.3%) in the control group (2; p=0.041). The mean operative time was 172 minutes (1) and 162 minutes (2), the EBL was 866 cc (1) and 855 cc (2), and the duration of admission was 36 (1) and 35 days (2), respectively. Radiologically, subsidence was 1.59 mm (1) and 1.67 mm (2). Clinically, one (1) and two (2) thigh pains were recorded and the functional score of Jensen was 2 (1) and 2.2 points (2), and the mobility score of Parker and Palmer was 5.2 (1) and 5.3 points (2), respectively. Conclusion: Prophylactic cable fixation is effective for reducing intra-operative femoral fractures.

Effect of a Series Connection of a Bi-Electrolyte Hydrogen Sensor in a Leak Detector

( Hyeuk Jin Han ),( Chong Ook Park ),( Young Kyu Hong ),( Jong Suk Kim ),( Jeong Woo Yang ),( Yoon Seo Kim ) 한국센서학회 2015 센서학회지 Vol.24 No.1

Conventional leak detectors are widely based on helium gas sensors. However, the usage of hydrogen sensors in leak detectors has increased because of the high prices of helium leak detectors and the dearth in the supply of helium gas. In this study, a hydrogen leak detector was developed using solid-state hydrogen sensors. The hydrogen sensors are based on Park.Rapp probes with heterojunctions made by oxygen-ion conducting Yttria-stabilized zirconia and proton-conducting In-doped CaZrO3. The hydrogen sensors were used for determining the potential difference between air and air balanced 5 ppm of H2. Even though the Park.Rapp probe shows an excellent selectivity for hydrogen, the sensitivity of the sensor was low because of the low concentration of hydrogen, and the oxygen on the surface of the sensor. In order to increase the sensitivity of the sensor, the sensors were connected in series by Pt wires to increase the potential difference. The sensors were tested at temperatures ranging from 500.600oC.

재발 또는 불응성 비호즈킨 림프종 환자에서 CDME 구제항암화학요법 후 고용량 항암화학요법 및 자가말초혈액 조혈모세포이식의 효과

김세형,한강원,배상병,김찬규,이남수,이규택,박성규,원종호,홍대식,박희숙 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.1

Background and objectives : The long-term survival in patients with non-Hodgkin's lymphoma (NHL) after conventional dose chemotherapy is about 35% and the rest of the patients tend to have relapse. So, in relapsed or refractory NHL, we compared the outcome of patients undergoing high-dose chemotherapy with autologous peripheral blood stem cell transplantation(APBSCT) with only salvage chemotherapy of cisplatin, dexamethasone, mitoxantrone, and etoposide(CDME). Materials and methods : From June 1993 to December 1999, 25 patients with relapsed or resistant NHL were treated with CDME regimen as salvage chemotherapy. Twelve patients were received four cycles of CDME chemotherapy, and 13 patients were received high-dose chemotherapy with APBSCT following two cycles of CDME chemotherapy. Results : The median follow-up duration was 12.8 months(range:4-68). The overall response rate was 41.7% (complete response rate 25%, partial response rate 16.7%) in 12 patients with CDME only. Thirteen patients who were treated with high-dose chemotherapy with APBSCT achieved 61.5% complete response rate and 15.4% partial response rate, with an overall response rate of 76.9%. The estimated 3-year progression-free survival rate was significantly higher among patients who received high-dose therapy than patients who received CDME only(41.5% vs 20.0%, p<0.05). And, 3-year overall survival rate was significantly higher among patients who received high-dose therapy(51.3% vs 25.0%, p <0.05). Conclusions : In relapsed or refractory NHL, CDME chemotherapy is an effective salvage chemotherapy and allow peripheral blood stem cell collection. Also, high-dose chemotherapy with APBSCT following CDME is superior to CDME salvage chemotherapy only.

LabVIEW를 이용한 유도전동기의 권선고장 자동진단

한동기(Dong-gi Han),송명현(Myung-hyun Song),박규남(Kyu-nam Park),이태훈(Tae-hun Lee) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.7

본 논문에서는 유도전동기의 고정자권선 고장진단을 목적으로 이상적인 전동기의 전류신호와 실시간으로 운전하고 있는 전동기 전류신호를 Park’s Vector에 각각 적용시켜 Park's Vector 패턴을 만들고 패턴 피크값의 기준치와 측정치의 편차를 이용하여 오차치를 벗어날 때 고장으로 진단하는 Park's Vector 패턴의 피크값을 이용한 고정자권선의 고장진단을 시도하였다. 숙달된 작업자가 Park’s Vector패턴을 보고 고장을 분석해야 했던 방법과는 달리 패턴을 비교하지 않고도 자동으로 고장을 진단하고 정보해주는 진단 방법을 제시하였다. 실제 전류분석 및 진단을 위해 상용 프로그램인 LabVIEW를 이용하였다.

LabVIEW를 이용한 소형 유도전동기의 권선고장 자동진단

宋明現(Myung-Hyun Song),朴奎南(Kyu-Nam Park),韓東奇(Dong-Gi Han),禹奕在(Hyeok-Jae Woo) 대한전기학회 2006 전기학회논문지 P Vol.55 No.4

In this paper, an auto detection method of stator winding fault of small induction motor is suggested. The Park's vector pattern which is obtained from 3-phase current signal by d-q transforming, is very good to detect winding fault. Comparing the Park's vector pattern of testing motor with its of healthy motor, the Park's vector pattern of fault motor is became an ellipse and the asymmetry is increased by the winding fault serios. So for detecting the dis-symmetry, id-filtered function, Min-value, and Max-value are suggested for auto detecting. Using LabVIEW programing, 3-phase healthy motor and several kind of winding fault motors are tested and the test results are shown that the suggested method can gives us a possibility of an auto detecting winding fault.

흰쥐 신장의 분화에 관한 조직화학적 연구

박경식,김동한,이규식 한양대학교 의과대학 1984 한양의대 학술지 Vol.4 No.1

Development and differentiation of mammalian kideney has been studied by many investigators. Hitreto, it has been known that a high vertebrate's kidney was differentiated from as a metanephros. As a result of the study of most investigators on developmental processes of metanephros in man rodents, they insisted that morphological development and differentiation of nephrons and collecting ducts should occur in the latter one quarter period of the fetal ages. But the initiation and completion time of renal function following its morphological development and differentiation have not been investigated perfectly. The author has determined the relationships of morphological and functional development of kidney were able to be revealed the studies of hydrolyzing phosphatase activities on the developing renal tissues. Therefore, in order to investigate the phosphatase activities of renal tissue following the development and differentiation of rate kidney, after interbreeding of healthy rats, fetuses of the 15th, 17th, 19th and newborns of the 1st, 4th, 7th and 10th day were sacrificed and were resected renal tissues. Histological preparations were prepared by way of hematoxylin and eosin stain for morphological changes of rat renal tissues, and Gomori's method(1941) for the detection of the activities of alkaline phosphatase, Gomori's method(1939) for the detection of the activities of acid phosphatase and Wachstein and Meisel's method(1957) for the detection of activities of ATPase were used, respectively. All of the preparations were observed with light microscope. The results were as follows; 1. The early differentiation of rat kidney began with glomerulus formation at the 17th day of fetal age, and morphological development was completed at the 21th day of fetal age, and lobulation of kidney was observed at the 7th day of neonatal age. 2. In the fetal kidney of the 17th gay, alkaline phosphatase activities were observed initially in the proximal tubules surrouding glomeruli in the cortico-medullary junction, and the activities were increased at the 17th day of fetus. At the 21th day of fetus, the strength of the enzyme activity was increased at the same time as renal tubule which showed alkaline phosphatase activity was increased in the cortex. In the each newborn kidney, the enzyme activities were continuously increased in the proximal tubules at the 1st, 4th, 7th and 10th day of newborns. The renal corpuscle and ascending straight tubule of the Henle's loop showed trace activities. 3. Acid phosphatase activity was shown at renal tubles and glomeruli during the fetal age after the 17th day of fetus, and moderate reaction of the enzyme was shown in the renal tubules, glomeruli, medullary rays and Henle's loops after birth. 4. Adenosine triphosphatase showed moderate reaction in the glomerulus at the 17th day and 19th day of fetus, and strong reaction was shown at the 21th day of fetus, and the ATPase activities of medullary rays showed trace reaction after birth. According to the beginning and change of the enzyme activity as mentioned above, it was supposed that the development of rat kidney should begin at begin at the 17th day of fetus. In the 21th day of fetus, diuresis and resorption were accoomplished mostly in the glomerulus and proximal tubule, and resorption of the Henle's loop began just before and after the birth.

DOC의 K-7 Mode에 의한 배기가스 저감에 관한 연구

한영출,백두성,오용석,박만재,박귀열,류규현 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.3

With the significant growth of the number of vehicles, environmental problems is raised. NOx, SOx, and PM emissions in diesel powered vehicles are larger than that in gasoline, because the development of pollutants reduction techniques has no: been yet achieved. So it is need to develop after-treatment or to convert into alternative fuel to satisfy emission regula-tion. Among the after-treatment systems to reduce the diesel emissions, studies with diesel oxidation catalyst(DOC) are done greatly. In this study using DOC, reduction efficiency with the change of temperature and catalyst loading was calculated through measurements of CO, HC, PM, and SOx.