Insulation Coating of Fe–Si–Cr Soft Magnetic Powder by Selective Oxidation

Jae‑Young Park,Kwangsuk Park,Bosung Seo,Julien O. Fadonougbo,Tae‑Wook Na,Ki Beom Park,Hyeon‑Tae Im,Nong‑Moon Hwang,Hyung‑Ki Park 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

This study examines the insulation coating technology of Fe–Si–Cr powder via selective oxidation annealing, which oxidizeselements selectively by controlling the oxidation potential. The study calculated the oxidation driving force of Fe, Si, andCr, and conducted a thermodynamic analysis of oxidation and reduction conditions according to temperature and oxidationpotential. Based on the results, a selective oxidation annealing was performed in an atmosphere in which Fe is reduced andonly Si and Cr are selectively oxidized. The oxidation potential was controlled through the partial pressure ratio of hydrogenand water vapor. The XPS analysis results confirmed that a Si and Cr complex oxide layer formed on the powder surfaceafter the selective oxidation annealing. Afterward, withstanding voltages were analyzed to evaluate the insulation property. Then, the withstanding voltage of the powder applying the selective oxidation annealing increased significantly comparedto that of the initial powder. Further analysis showed that the powder annealed in an air atmosphere had a significantly lowersaturation magnetic flux density than the initial powder, while the powder applying the selective oxidation annealing hadonly a slightly reduced saturation magnetic flux density.

가스화 - 수소 회수 공정 개발을 위한 예비실험

차재준(Jae-Jun Cha),김영석(Young-Suk Kim),이진호(Jin-Ho Lee),황순모(Soon-Mo Hwang),정성재(Seong-Jae Jeong) 한국열환경공학회 2010 한국열환경공학회 학술대회지 Vol.2010 No.춘계

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

반구형 딥-드로잉 공정에서 동적 외연적 해석방법에 관한 연구

정동원,황재신 제주대학교 공과대학 첨단기술연구소 2003 尖端技術硏究所論文集 Vol.14 No.2

In the present work a finite element formulation using dynamic explicit time integration scheme is used for numerical analysis of auto-body panel stamping processes. Analyzed auto-panel stamping process correction of forming using common use software called Dynaform using dynamic extensive method. The developed algorithm is also capable of calculating the diagram black shapes as the initial state of binder wrap condition for large scale parts such as a fender or a rear quarter part. Further, the simulated results for the total auto-body panel stamping processes are shown and discussed. Its application is being increased especially in the automotive industrial area for the cost reduction. weight saving, and improvement of strength.

고관절 주위 대퇴 직건에 발생한 석회화 건염-1예보고-

성일보,황순호,안종국,정병현,염재광,황재광,정형진,김진호 대한고관절학회 2001 Hip and Pelvis Vol.13 No.1

英語學習의 效肉的方法에 對한 小考

황재호 한사대학 학생지도연구소 1980 학생지도연구 Vol.4 No.-

디지털 스튜디오의 효율적인 시스템 구성과 운영관리 방안 연구

황현진,장노순,이재홍 강원대학교 정보통신연구소 1998 정보통신논문지 Vol.2 No.-

This paper presents the efficient system architecture of a digital studio and its operation and maintenance. This paper shows the overview of the system components and explains their technical features in detail, and discusses system installation and operational test procedures. And then technical requirements and procedural schemes for system implementation have been proposed and the operational organization, training programs, and maintenance planning have been qeneralized and analyzed. It shows that essential points for constructing the optimum system are to follow a supply-demand curve of its markets and industries and to make technical innovations of system implementation. Training programs for system operators and administrators are also very important factors. The integration of such factors makes it possible to construct the efficient a digital studio.

지방산 금속염의 합성과 형태분석

黃匡鎭,李財惺,李財鶴 홍익대학교 산업기술연구소 2003 産業技術 Vol.13 No.-

The metal salts of various fatty acids were prepared and their SEM data are collected. The morphology of metalated fatty acids (decanoic, stearic and 12-hydroxyst earic) showed more branched thread-like clusters than those of fatty acids. Among the prepared metal salts of various fatty acids, the morphology of lithium 12-hydroxystearate (Li-HSA) showed some similarity to the reticular structure suitable to be a proper thickener in grease formulation.

순환기 내과로 자문의뢰된 환자의 임상상

황진용,최지용,손상균,조용근,채성철,전재은,박의현 慶北大學校 醫科大學 1996 慶北醫大誌 Vol.37 No.4

목적 : 순환기내과 영역은 많은 과로부터 자문의뢰를 받는 영역으로 알려져 있다. 특히 최근 우리나라의 순환기질환의 유형이 변화되고 입원환자가 고령화되면서 동반된 심질환의 유병율도 증가하고있다. 이에 저자들은 타과로 입원하여 순환기내과로 자문의뢰되는 환자의 임상상과 3차병원인 경북대학교병원에서의 순환기내과자문의 유용성 등을 평가하여 향후 순환기질병에 대한 협의진료에 도움을 주고자 본 연구를 시행하였다. 방법 : 1995년 3월부터 순환기내과로 공식자문의뢰된 첫 100명을 대상으로 전향적으로 연령, 의뢰이유, 최종진단명, 수술과의 관련성 여부, 순환기내과의 최종조치, 타과의 순응도 등을 조사하였다. 결과 : 1) 자문을 의뢰한 환자는 평균 58±16(15-89, 중앙치 61)세였고 60세이상의 환자가 57%로 고령의 환자가 많았다. 2) 내과계열 25%, 외과계열 75%로 외과계열의 자문이 많았고 일반외과가 26%로 가장 많았고 내과의 다른 분과가 12%, 신경외과 12%, 정형외과 11%, 흉부외과 11%, 신경과 11% 등의 순이었다. 외과계열중 수술을 시행한 경우는 58례로 이중 응급수술이 13례였다. 술전 위험도 평가를 위한 자문이 38례에서 있었는데 순환기적인 문제로 수술을 받지 못한 경우는 2례(1례는 허혈성 심질환, 1례는 심낭질환)이었다. 이때 응급수술을 제외한 입원일과 술전 자문일파의 간격은 평균 3±7일(입원일-42일)이고 술전 자문일과 수술일과의 간격은 평균 6±4일(1-16일)이었다. 3) 타과의 의뢰이유는 심전도 이상이 36례, 높게 측정된 혈압이 20례, 순환기질환의 과거력 17례, 환자의 증상 때문인 경우가 10례였고 심전도의 이상중에는 부정맥이 18례, 이상 Q파 6례, ST절 이상이 5례, 각차단이 3례의 순이었다. 순환기과거력 중에는 허혈성 심질환이 6례, 현재 혈압은 정상이나 고혈압의 과거력이 있는 경우가 4례 순이었고 환자의 증상은 흉통 6례, 호흡곤란이 3례, 기절이 1례였다. 4) 자문후 최종진단이 가능했던 91례를 진단별(총 97 진단명)로 나누어 보면 고혈압이 28례, 부정맥이 16례, 허혈성 심질환이 14례, 판막질환이 11례, 순환기질환이 아닌경우가 19래였다. 이들중 추적진료가 필요하다고 응답한 경우가 57례였으나 순환기내과 외래에 1번이상 추적진료한 경우는 32례(56%)로 환자의 순응도는 낮았다. 결론 : 순환기내과의 자문의뢰는 고령자에게 많았고 수술과 관련된 경우가 많았으며 심전도의 이상이 의뢰이유로 가장 많았으며 진단별로는 고혈압과 부정맥이 가장 많았다. 그리고 순환기적인문제로 수술을 받지 못한 경우는 드물었고 자문후 지속적인 추적진료를 위해 환자의 교육이 필요하겠다. Objective : Clinical characteristics of the patients with cardiovascular diseases in the general hospital have been changed and prevalance of co-existing cardiovascular disease in the patients who were admitted for non-cardiac diseases has been increased remarkably as the proportion of elderly patients increased rapidly in Korea. We evaluated clinical features of the patients consulted for cardiological evaluation and effectiveness of the consultation in the setting of tertiary general hospital, Kyungpook University Hospital. Method : One hundred patients were studied between January 1995 and January 1996. They were evaluated for the reason of consultation, final diagnosis, final recommendation from cardiologists and its impact on the management of the patients, and compliance of the consulting departments. Results : 1) The ages ranged between 15 and 89 (mean 58±16, median 61) years, 57 patients were male and 43 female. Fifty seven patients were older than 60 years. 2) Consultations from surgical parts were 75 patients. Consultation from general surgery was most frequent (26%), followed by other divisions of internal medicine (12%), neurosurgery (12%) and orthopedic surgery (11%), chest surgery (11%), neurology (11%), obstetrics and gynecology (8%), urology (4%), ophthalmology (2%), dermatology (2%), ENT (1%). Among 75 patients from surgical parts, operation was done on 58 patients, including 13 emergency cases. Preoperative cardiac risk evaluation was the reason of consultation in thirty eight patients, of which operation could not be done in only 2 patients (one had severe ischemic heart disease, the other large pericardial disease). Interval between consultation day and operation day was 6±4 days (1-6 days). 3) Reasons for cardiac consultation were electrocardiographic (ECG) abnormalities in 36 patients, high blood pressure in 20 patients, previous cardiovascular diseases in 17 patients, symptoms of the patients in 10 patients. Among EGG abnormalities, arrhythmias was the reason in 18 patients, abnormal Q waves in 6 patients, ST-T segment abnormalities in 5 patients, bundle branch block in 3 patients. Among previous cardiovascular disease, presence of ischemic heart disease was the reason in 6 patients, previous hypertension in 4 patients. Chest pain was the reason of the consultation in 6 patients, dyspnea in 3 patients, syncope in 1 patient. 4) Definite diagnoses could be made in 91 patients with 96 diagnoses which were hypertension and its complications in 28, arrhythmia with underlying disease in 16, ischemic heart disease in 14. valvular heart disease in 11, non-cardiovascular disease in 19. Cardiological follow up was recommended in 57 patients. However, 25 patients (44%) were lost to follow-up. Conclusion : Cardiological consultation was frequent in the elderly patients. Most frequent reason for consultation was EGG abnormalities. Hypertension or arrhythmia was most common final diagnosis. Inoperability due to cardiovascular problems were rare.