Al-Pb 계 합금분말의 성형 및 소결 특성에 관한 연구

문종태,이영근,이용호,조성석 ( Jong Tai Moon,Young Kun Lee,Yong Ho Lee,Sung Suk Cho ) 한국주조공학회 1990 한국주조공학회지 Vol.10 No.5

N/A By using the centrifugal atomization, which is one of the rapid solidification processes, Al-5, 10wt%Pb alloys which are monotectic alloys were melted at 150K over two liquid phase line in the phase diagram. The melted alloy was poured on the rotating disk, being made into atomized powders, and then the solidified microstructure and morphology of the powder were investigated. This study converted the produced powders into strips by strained powder rolling. According to sintering temperature, the microstructure and hardness were investigated. The solidified structure of the powders were almost cellular dendritic structure. Pb particles (2.0-3.0㎛) were fairl distributed in the Al matrix. Powder shapes were irregular. Rolling property and the compacting was good, respectively, because of increasing mechanical interlocking and surface area in the small size powders. With increasing temperature, the boundarys of powders were in porous form due to the diffusion. Pb particles which were surrounding the pores were inverse-segregated at the surface of the powders. With increasing of sintering temperature, the hardness of the powders and the strips decreased. In particular rolling-strip, the hardness abruptly decreased due to the release of work-hardening.

만성교약성심낭염의 외과적 치료

김종환(Chong Whan Kim),이영근(Young Kun Lee),노준량(Joon Rhying Rho),손광현(Kwang Hyun Sohn),서경필(Kyung Phill Suh),이영균(Yung-Kyoon Lee),김광우(Kwang Woo Kim),곽일용(Il Yong Kwak),홍창의(Chang Yee Hong),장재헌(Jae Hun Chang) 대한외과학회 1971 Annals of Surgical Treatment and Research Vol.13 No.1

신개념 뇌경보 시스템 개발

최수연(Su-Yeon Choi),박찬용(Chan Yong Park),길경석(Gyung-Suk Kil),안창환(Chang-Hwan Ahn),이영근(Young-Kun Lee) 한국조명·전기설비학회 2008 한국조명·전기설비학회 학술대회논문집 Vol.2008 No.10월

This paper described a New-Concept lightning warning system(LWS) which can measure electric field intensity on the ground level by an electric field mill (EFM) and calculate the lightning location by radiated electro-magnetic waveform. The EFM measures electric field up to 20[㎸/m] with the sensitivity of 0.15[V/㎸/m] and frequency bandwidth of the loop antenna was ranges from 5.2[㎑] to 1.71[㎒J. The LWS provides data on the movements of thunderclouds and the possibility of lightning return stroke.

뇌방전 이치표정에 관한 연구(Ⅰ)

길경석(Gyung-Suk Kil),박대원(Dae-Won Park),김일권(Il-Kwon Kim),최수연(Su-Yeon Choi),안창환(Chang-Hwan Ahn),이영근(Young-Kun Lee) 한국조명·전기설비학회 2007 조명·전기설비학회논문지 Vol.21 No.10

뇌경보시스템은 낙뢰에 의한 인적 물적 피해를 예방하는 중요한 장치이다. 본 논문에서는 뇌경보시스템의 주요 기능으로 뇌운의 이동과 활동을 감시할 수 있는 뇌방전 위치표정 알고리즘 및 회로에 대해 연구하였다. 뇌방전시 발생하는 전계성분은 Whip 안테나와 공진주파수 300(㎑)의 협대역 공진증폭기로 검출한다. 자계파형 측정회로는 직교루프코일과 적분증폭기로 구성되며 주파수 대역은 5[㎑] ~l.2[㎒]이다. 전계파형으로 뇌방전의 극성을 판별하고, 자계파형의 크기와 영점교차점에 의해 방향과 거리를 산출하여 뇌방전의 위치를 표정한다. Lightning warning system plays an important role in protecting human life and other facilities from lightning return strokes. This paper dealt with lightning positioning algorithms and circuits as a main function of lightning warning system, which monitor movements and activities of thunderclouds. Electric field component produced by lightning discharge is detected by the configuration of a whip antenna and a narrow-band resonance amplifier with center frequency of 3OO[㎑]. Measurement circuit of magnetic field waveform consists of a crossed-loop coil and an integral amplifier, and its frequency bandwidth is ranges from 5[㎑] to 1.2[㎒]. The polarity of lightning discharge is discriminated by electric field component After fixing the polarity, we can calculate the direction and distance of lightning discharge by the peak and the zero-cross time of magnetic field waveform.

Spring鋼의 熱處理가 疲勞强度에 미치는 影響에 關한 硏究

李龍鎬,李榮根 弘益大學校 1984 弘大論叢 Vol.16 No.2

The SUP-9A steel had got its untempered martensite structure by oil quenching after austenitizing at 850℃, 40min. The writer, then, examined the effect of tempering temperature on the mechanical properties and the fatigue limits in SUP-9A steel at each tempering temperature 100℃, 200℃, 300℃, 400℃, 500℃, and 600℃. The results from this examination were as follows: (1) Hardness and tensile strength were decreased as tempering temperature increased, and the more tempering tempreature increased, the more its impact absorbed energy and elongation did. (2) Fracture in tensile-test specimens produced the curved radial marks as tempering temperature increased, and the final fatigue fracture region moved toward the center of the section as the nominal stress increased. (3) Microstructure took spherical and coarse form of carbide particles as tempering temperature increased. (4) Full width of half maximum intensity of martensite(211) plane was decreased by increasing the tempering temperature. (5) The highest fatigue limit appeared at the tempering temperature 400℃.

Waterston 수술에 관한 실험적 연구 : An Experimental Study

이영근 최신의학사 1971 最新醫學 Vol.14 No.10

A histologic study of the lung was done in 28 dogs after Waterston's operation. The diameter of anastomosis stoma was about 5mm. Out of ten dogs expired after operation 3 cases were due to acute intractable cardiac failure in spite of digitalization. Fourteen long-term survivors and 4 short term survivors were obtained. One, two, three, four, and six months postoperative long term survivors were sacrificed after auscultation and aortography. A large bore polyethylene catheter was inserted into the left ventricular cavity through the apex and 20 to 40 cc of 80% iodine dye was injected manually. The following observatins were made. (A) Auscultation of the chest In every survivors continuous machinery murmur was auscultated, showing patency of the aorticopul?monary shunt operation stoma. B. Pulmonary arteriography by left ventricular dye injection showed simultaneous opacification of the bilateral pulmonary arteries with the aorta in every case, which shows patency of the anastomosis stoma. Pulmonary artery dilation extended into the peripheral branches. C. Histological findindings In lung parenchym, congestion, alveolar dilatation, alveolar rupture, alveolar wall thickening, and capillary formation were noted in the one month specimens. The above mentioned findings increased in intensity among two months group, after which the findings were rather stable, showing little changes. Pulmonary vascular changes were characterized by intimal proliferation, medial hypertrophy and connective tissue proliferation in the adventitia. In pulmonary arterioles, histologic changes were prominent in the specimens after 2 months, showing slight or little changes after that period. The thickening of the arteriole walls were mainly due to medial hypertrophy. In muscular arteries changes were noted after 2 months and increased after that period, showing the most prominent changes in-4he 6 month specimens and medial hypertrophy was the most conspicuous findings. This experimental results suggest the possibility that in chinical Waterston operation, pulmonary vascular changes may occur at the relatively earliest postoperative period, especially when the aorto?pulmonary anastomosis stoma is a large one.

前交通動脈瘤에 對한 手術成績分析

宋鎭彦,李永根,崔昌洛,姜俊基,宋將成,河榮秀,李春章,金達洙,成台慶,安明洙,許春雄,朱文培,金英鎭 대한신경외과학회 1974 Journal of Korean neurosurgical society Vol.3 No.2

The authors attempted to analyse the factors influencing the mortality involved in aneurysm surgery based on 38 cases of intracranial surgery for anterior communicating aneurysms, and obtained the following conclusion. 1. The surgical results are much better when the aneurysm surgery is delayed over one week after the occurrence of aneurysmal rupture, if there is no evidence of intracerebral hematoma. Administration of a massive dosage of epsilon aminocaproic acid in the waiting period prior to aneurysm surgery seems to be effective for preventing recurrence of bleeding from the aneurysm. 2. The direction of the anterior communicating aneurysm should be clearly visualized on a cerebral angiogram so that the most effective aneurysmal approach can be selected in surgery. 3. Microsurgery and hypotension in aneurysm surgery minimize brain damage in the exposure of aneurysm and provide accurate isolation of the aneurysmal neck from the parent vessel in aneurysmal neck ligation. 4. Proximal ligation of the anterior cerebral artery is also an effective procedure to prevent recurrent hemorrhage from anterior communicating aneurysm.

대동맥 이식에 관한 실험적 연구

김종환,이영근,김용락,노준량,이영균 中央醫學社 1970 中央醫學 Vol.18 No.4

外傷性 橫隔膜 헤르니아 : A Report of Two Caess

朴永寬,李榮根,徐景弼,李寧均 現代醫學社 1968 現代醫學 Vol.9 No.4

Two cases of traumatic diaphragmatic hernia were operated on in this department during the past 12 months period. The. first case, a 14 years old girl, had laparotomy for intestinal perforation inflicted by traffic accident at another hospital. After suturing the perforated jejunum, she was transferd to this hospital due to coincidental rupture of the left leaf of the diaphragm. Prompt reposition and repair of the diaphragm was done utilizing transthoracic approach. The second case was a 26 years old man, who was admitted with severe abdominal pain and vomiting. Two years ago he was stabbed with a knife in the left lower lateral chest wall. By chest P-A and barium enema study stomach and colon were noted in the left bemithorax. A round defect, 3.5 cm in diameter, was found in the muscular portion of the left diaphragm, which was repaired after reposition of the herniated abdominal viscera. Transthoracic approach was used in this case, too. Both cases were discharged after uneventful recovery.

전통식품이 Escherichia coli O157의 생존에 미치는 영향

차인호,김용균,최영환,이영근,김근기 密陽産業大學校 農業技術開發硏究所 1999 農業技術開發硏究所報 Vol.3 No.2

우리 고유의 전통식품인 고추장과 된장이 E. coli O157의 증식에 미치는 영향을 살펴본 결과 다음과 같은 결론을 얻었다. 1. E. coli O157을 시중에 판매되는 고충장의 농도1.6%, 3.1%, 6.3%, 12.5%, 25.0% 와 혼합하여 실온에서 정치배양한 결과 E. coli O157 은 각각 96.7%, 77.1%, 37.2%, 27.3% 및 7.5% 가 억제되었으며, 낮은 농도가 높은 농도의 고추장보다 더 높은 억제효과를 보였다. 2. 시중에서 시판되고 있는 된장의 농도 1.6%, 3.1% 및 6.3%에 E. coli O157을 접종한 다음 실온에서 정치배양한 결과 E. coli O157은 각각 80.9%, 62.1% 및 9.2%로 억제되었으나, 12.5%와 25.0%의 된장 농도에서는 저농도와는 반대로 12.5% 및 168.3%의 증식효과를 나타내어 이와 같은 현상의 규명에 대한 구체적인 연구가 필요한 것으로 사료되었다. This study was conducted to determine the survival of E. coli O157 on the Korean native traditional foods such as Kochujang and Doenjang. The inhibition rates of E. coli O157 by concentrations of 1.6%, 3.1%, 6.3%, 12.5% and 25.0% of Kochujang were 96.7%, 77.1%, 37.2%, 27.3% and 7.5%, respectively. E. coli O157 was more inhibited at lower than high concentration of Kochujang. In the test inhibition rates by Doenjang, E. coli O157 was inhibited at concentration of 1.6%, 3.1% and 6.3% of Doenjang, and inhibition rates by these concentrations were 80.9%, 62.1% and 9.2%, respectively. However, E. coli O157 was increased at concentrations of 12.5% and 25.0% compared with controls.