Effect of Ultrasonic Melt Treatment on Solidification Microstructure of Al–5Ti–1B Alloy Containing Numerous Inoculant Particles

Soo‑Bae Kim,Jae‑Gil Jung,Young‑Hee Cho,Su‑Hyeon Kim,Kwangjun Euh,Jung‑Moo Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The effect of ultrasonic melt treatment (UST) on the solidification microstructure of an Al–5Ti–1B alloy containing highvolumefractions of Al3Tiand TiB2particles is investigated for various UST times with different melt holding times. Theas-cast Al–5Ti–1B alloy is composed of TiB2and polygonal Al3Tiparticles (present prior to UST), plate-like Al3Tiparticles,and Al grains (formed during UST and/or solidification). The UST causes a size reduction and homogeneous distributionof the TiB2-agglomerated region containing many submicron-sized TiB2particles pushed to the grain boundaries. The USTslightly decreases the size and improves the distribution of polygonal Al3Tiparticles enriched in the TiB2-agglomeratedregion. Unlike the TiB2and polygonal Al3Tiparticles, which exhibit a minor refining effect, the plate-like Al3Tiparticlesshow a significant refinement with UST application. The UST has a significant effect on the size distribution of Al grains byinducing the formation of medium-sized grains at the expense of small and large grains; however, it only has a slight effecton grain refinement. The degree of microstructure modification increases with increasing UST time but decreases with meltholding time after UST. The mechanisms for the refinement and dispersion of the TiB2and Al3Tiparticles and Al grains arediscussed considering fragmentation, nucleation, and growth behaviors induced by the UST and subsequent solidification.

대퇴동맥을 통한 경피적 관동맥 중재시술 환자의 천자부위 지혈을 위한 Angioseal^(�) 사용과 고식적 용수 압박법의 비교 : 전향적 연구

김용훈,권현철,김필호,안석진,유철웅,최진호,이상철,김준수,김덕경,전은석,이상훈,홍경표,박정의,서정돈 대한내과학회 2004 대한내과학회지 Vol.66 No.5

목적 : 경피적 관동맥 중재술은 최근 양적 및 질적으로 급격한 발전을 보였지만 시술 시 천자부위의 혈관 합병증은 아직 해결해야 할 문제점이다. 저자들은 대퇴동맥을 통한 경피적 관동맥 중재술을 환자에게 천자부위 지혈을 위한 혈관폐쇄기구인 안지오실의 안전성과 유용성을 고식적인 용수 압박법과 비교 연구하고자 하였다. 방법 : 2002년 4월부터 2003년 5월 사이에 삼성서울병원 심장혈관센터에서 대퇴동맥을 통한 경피적 관동맥 중재술을 성공적으로 시행한 200명의 환자(안지오실 사용군: A군, 100명, 고식적 용수압박법 사용군 B군, 100명)를 대상으로 시술 후 주요 합병증 및 경한 합병증, 지혈 후 환자가 자리에 앉기까지의 시간, 보행개시 가능시간, 총 재원 기간과 시술 1주 후의 합병증을 전향적으로 조사하여 비교 연구하였다. 결론 : 두 군에서 연령, 성별, 기저질환, 심혈관 질환의 위험요소, 시술의 종류, 시술 중 사용한 헤파린의 양, clopidogrel의 양, ticlopidine의 양, 지혈 시 수축기와 확장기혈압, ACT (activated clotting time)는 차이가 없었다. A군이 B군에 비해 시술 후 자리에 앉기까지의 시간 (A군: 4.3±0.3시간, B군: 13.7±0.8시간, p=0.004) 및 보행개시까지의 시간(A군: 6.8±0.5시간, B군: 18.8±2.1시간, p=0.013)이 유의하게 짧았다. 시술 후 주요 합병증은 두군 모두에서 관찰되지 않았으며, 경한 합병증의 전체발생은 A군에서 유의하게 적었다(A군: 28명, B군: 19명, p=0.003). 반상출혈의 경우는 A군에서 유의하게 낮았지만(A군: 3명, B군: 12명, p=0.01), 혈종, 출혈의 발생은 두군간에 차이가 없었다. 총 재원기간에는 두 군간에 차이가 없었다(p=0.239). 시술 1주 후 경과관찰에서 주요합병증은 역시 두 군 모두에서 관찰되지 않았으며, 경한 합병증의 전체발생은 두 군에서 차이가 없었다(A군: 15명, B군: 13명 p=0.418), 반상출혈의 빈도는 차이가 없었지만 혈종의 발생은 A군에서 더 낮았다(A군: 2명, B군:6명, p=0.004). 두 군 모두에서 출혈은 발생하지 않았다. 결론 : 대퇴동맥을 통한 경피적 관동맥 중재술을 시행한 환자에서 안지오실의 사용은 고식적 용수 압박법에 비해 환자의 침상 안정시간을 줄여 조기 활동개시가 가능하게 하였으며 국소합병증의 위험도를 일부 낮추어, 시술에 따른 환자의 불편을 현저하게 감소시킬 수 있다고 할 수 있을 것으로 기대된다. Background : Although the number and the quality of percutaneous coronary intervention have been recently increased dramatically, the vascular complication at puncture site is still the major cause of patients' morbidity. We evaluated the safety and efficacy of newly of newly-developed collagen-based arterial closure device, Angioseal after transfemoral percuatenous coronary intervention. Methods : This study was designed as a prospective single center non-randomized comparative study. A total 200 patients undergoing transfemoral percutaneous coronary intervention were enrolled between April 2002 and May 2003. They were divided into two groups; Angioseal group (group A, n=100) and manual compression group (group B, n=100). The baseline clinical and angiographic characteristics were reviewed. The time to sit up, the time to ambulation, the duration of hospital stay, major and minor vascular puncture site complications were monitored. The patients were followed-up for 1 week after procedure by telephone. Results : The baseline clinical characteriwtics, clinical diagnosis, cardiocascular risk factors, typesof procedure, doses and numbers of anticoagulants were similar between two groups. The blood pressure and activated clotting time were also similar. The time to sit up (group A: 4.3±0.3 hours, group B: 13.7±0.8 hours, p=0.004) and the time to ambulation (group A: 6.8±0.5 hours, group B: 18.8±2.1 hours, p=0.013) were shorter in group A. No major vascular complications were noted. The incidence of hematoma and bleeding were not significantly different between two groups. The incidence of ecchymosis, however, was significantly lower in group A (group A:12%, group B: 3%, p=0.001) The duration of gospital stay was similar between groups. During 7 days of follow-up period incidence of hematoma was significantly lower in group A (p=0.004). Although the incidence of ecchymosis was not significantly different between two groups. Conclusion : The angioseal may be associated with earlier ambulation and less patients' morbidity with low incidence of local complication rate compared to manual compression after transfemoral percutaneous coronary intervention.

Rifampicin에 의한 것으로 추정되는 위막성 대장염1예

김수현,이은우,정종혁,문승현,김동한,양혁승,오영상,김호동,김도현,박혁,박정환,박경옥,이영직 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Pseudomembranous colitis, caused by altering the normal colonic flora and allowing the multiplication of Clostridium difficile, is an deleterious adverse effect of antibiotics. But it is rarely reported by rifampicin. Rifampicin is one of the first line drug in the treatment of tuberculosis and many patients are exposed to its potential adverse effects. We experienced a patient that had abdominal discomfort and hematochezia due to pseudomembranous colitis after receiving antituberculous medication, and which was probably caused by rifampicin. A 82 years old man was admitted with abdominal discomfort and hematochezia for one week. On the past history he had been diagnosed as endobronchial tuberculosis about 4 months ago. Colonoscopy revealed multiple discrete whitish mucosal lesion on rectosigmoid colon, and histologic findings were consistent with pseudomembranous colitis. The antituberculous agents were discontinued and vancomycin was administered. The patient's symptoms were resolved within several days. There was no recurrence after reinstitution of the antituberculous agents excluding rifampicin. We report here on a case of pseudomembranous colitis probably due to rifampicin.

열 변화에 의한 구리전선의 미세조직 및 상 변화에 관한 연구(Ⅲ)

박성우,김윤회,김상현,박남규,김수철,김영만 內務部 國立科學搜査硏究所 2002 國立 科學 搜査 硏究所 年報 Vol.34 No.-

Proportion And Characteristics Of Transient Nodules In A Retrospective Analysis Of Pulmonary Nodules

( Jin Yeong Yu ),( Su Young Chi ),( Hee Jung Ban ),( Yong Soo Kwon ),( In Jae Oh ),( Kyu Sik Kim ),( Yu Il Kim1 ),( Sung Chul Lim ),( Song Choi ),( Yun Hyeon Kim ),( Young Chul Kim ) 대한내과학회 2011 대한내과학회 추계학술대회 Vol.2011 No.-

S.D. Rats를 이용 1, 1-Dichloro-1-fluoroethane의 아민성 흡입독성 연구

김현영,이성배,임철홍,김철우,점용현,한정희,전윤석,최수영,강대봉,이용묵 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.1

There were no specific effects for test materials on Sprague-Dawley (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body l, l-Dichloro-1 -fluoroethane (used as coolant, metal cleaner and solvents) exposure(0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations, there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration. Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-l -fluoroethene inhalation was evaluated in groups with 3,000 ppm below (S .D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-l-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure .

원발성 폐암 환자의 생존율에 관한 보고

김현태,이상무,어수택,박춘식,정성환,허승재,남충희,강창희,김용훈 순천향대학교 1994 논문집 Vol.17 No.4

We analysed 404 patients with primary lung carcinoma who were treated at Soonchunhyang University Hospital from July, 1985 to september, 1993 in order to investigate the survival rate and epidemiolgical properties of primary lung cancer. They were 330 males and 74 females. The most prevalent decade was seventh. In terms of cell type, the squamous cell was 225 patients (55%), and adenocarcinoma, small cell, mixed type was 21%, 19%, 4%, respectively. Among non-small cell lung carcinoma, stage Ⅲa was the most prevalent one(92%). In case of small cell carcinoma, the limited stage was 64%. The 12-, 24-, 36- month survival rate of total patients was 57%, 31%, 22%, respectivley and median sruvival time was 15 months. The 36-month survival rate tended to be longer in non-small cell lung carcinoma than that of small cell lung cancer, but there was no difference between two groups, statistically. In non-small cell carcinoma, The 36-month survival rate and meidan survival time were longer in the stage Ⅰ and Ⅱ than those of Ⅲa, Ⅲb, Ⅳ (80% versus 38%, 22%, 0%, p<0.05). According to involvement of lymph node, the 36-month survival rate was longer in NO and N1 than those of N2, N3 (61.9%, 48.7% versus 17.7%, 17.3%, p<0.05). In small cell carcinoma, The 36-month survival rate and median survival rate were higher and longer in limited stage than those of extensive stage(16.1% and 13 month vs 10% and 8 month, p<0.05). In conclusion, we report here the incidence of primary lung carcinoma and the survival rate of paients with primary lung carcinoma who were treated in Soonchunhyang University Hospital.

무궁화 위성방송 수신용 고이득 마이크로스트립 배열안테나의 설계

김진생,신현철,이문수 慶尙大學校生産技術硏究所 1996 生産技術硏究所論文集 Vol.12 No.-

In this paper, a microstrip array antenna for receiving KOREASAT broadcasting is designed, which has left-handed circularly polarization property with the gain of 29dB at 11.84GHz. An antenna using a single feed point is chosen as an array element because of its simplicity and low feeding loss. The 2 X 2 array is a basic array element to achieve the overall 16 X 16 array antenna. All the elements of the array are fed in phase using the parallel feed method for broadside beam radiation. The actual dimension of array is about 30 X 30cm. The measured return loss and VSWR is in a good agreement with the calculations. The measured results are as follows ; SLL of -15dB below, gain of 27dB, directivity of 31.9dBi, and axial ratio of 0.74dB at 11.84GHz.

소프트웨어 테스팅을 위한 효과적인 탐침 삽입 기법

김현수 忠南大學校 産業技術硏究所 2003 산업기술연구논문집 Vol.18 No.2

In order to determine which basic blocks are covered by a test set, coverage tools insert probes at various program locations, usually one per basic block. Probes, however, obviously increase the size of the program's object code as well as its execution time. If we can reduce the number of probes inserted in a program, its object code size and the runtime overhead can be reduced. In this paper we present an effective technique to find an optimal group of nodes of a flowgraph that satisfy the following property: A test set that exercises all nodes in the group exercises all nodes in the flowgraph. Actually the group of nodes means optimal program locations at which probes will be inserted. The technique may be used to significantly reduce the cost of coverage testing of programs.

레트로바이러스의 표면단백질 : 인슐린의존형 당뇨병의 동물모델인 NOD 쥐의 혈청과 반응하는 새로운 자가항원 A New Autoantigen Reactive with Non Obese Diabetic (NOD) Mice Sera

김경수,김기환,김현만,윤지원,강엽 아주대학교 1997 아주의학 Vol.2 No.2

IDDM (Insulin dependent diabetes mellitus) is believed to be an autoimmune disease and characterized by the immune activation against insulin-producing pancreatic beta cell. The identification and characterization of new autoantigens reactive with an activated immune System would heip to elucidate the pathogenic mechanism of this disease. Several autoantigens are trying to apply for diagnosis and prevention of IDDM. The NOD (non obese diabetic) mice have been the best model for studying the pathogenesis of human IDDM. To identify new autoantigens reactive with activated humoral immunity of NOD mice, the lambda gt11 cDNA library was constructed from NOD-derived pancreatic beta cell (MIN6N8a: mouse insulinoma cell) and screened with prediabetic NOD sera. Mine positive dones were selected from 2x10^(5) phage plaques. The 5'-end sequencing and homology searching showed that six clones from nine clones had over 98% sequence homolgy with the retroviral envelope gene. Full sequendng reveated that the cloned gene was a fragment of ecotropic retrovirus (emv-3) envelope gene. To confirm the immunoreactivity of doned retroviral envelope protein, the cloned gene fragment was expressed in an E.coli expression vector System. Western blotting showed that the recombinant envelope protein fragment also reacted with prediabetic NOD sera.