진공열간가압성형 (VHP) 법 및 압출로 제조한 SiCp/Al 및 SiCp/2024Al 복합재료의 동적탄성계수와 감쇄능 (내부마찰) : 금속기 복합재료의 동적탄성계수 및 감쇄능 측정

김영만,조기현,이경민,홍성길 대한금속재료학회(대한금속학회) 1999 대한금속·재료학회지 Vol.37 No.9

To shorten the processes of MMC fabrication, a number of techniques are being studied. In this study, a new process for MMC's fabrication was developed utilizing vacuum hot pressing and subsequent extrusion. MMC's with pure Al and 2024Al matrices reinforced with various volume fractions of SiC particulates were produced at 400℃ by vacuum hot pressing(VHP), followed by direct extrusion with extrusion ratios of 10:1 at 480℃ at constant ram speed of 2㎜/sec. The effects of extrusion pressure and relative density according to the volume fractions of the reinforcement were compared with the resultant metallurgical microstructures. Young's moduli of the manufactured composites were measured by the sonic resonance method, damping capacity by free decay method. Measured Young's moduli of the composites at room temperature were compared with the predictions based on Rule of Mixtures, Halpin-Tsai and Mean-field models. Measured Young's moduli of the composites are in good agreement with the predictions based on Mean-field model. The composites reinforced with finer particles showed higher damping capacity under the same amount of SiC reinforcement.

급성 골수성 백혈병 환자에서 발생한 침습성 아스페르길루스중에 대한 수술적치료 1 예

배영환;어원식;어상민;김승만 김태영;박수영;서영경;정은주;안효정 인제대학교 2011 仁濟醫學 Vol.32 No.-

Invasive pulmonary aspergillosis is known to have a poor prognosis and major cause of morbidity and motality in patients with hematologic disease. Without adequate therapy, invasive pulmonary aspergillosis will almost always progress to fatal pneumonia. Early administration of antifungal agents in patient with invasive pulmonary aspergillosis is most important. And surgical resection of aspergillous-infected tissue may be useful in patients with lesions that are contiguous with great vessel and lesions causing hemoptysis. We reported a rare case of surgical resection as curative treatment for invasive pulmonary aspergillosis patient in 58-year-old man who had the history of acute myeloid leukemia.

태권도 앞굽이 몸통반대지르기를 통한 고령자의 건각도의 유효성 분석

김기만(Ki Man Kim),배영상(Young Sang Bae) 한국발육발달학회 2009 한국발육발달학회지 Vol.17 No.4

The purpose of this study was to identify effectiveness of Taekwondo Apkubi Momtong Bandae Jireugi (AMBJ) as diagnostic method of health related to muscle level of older men. To accomplish the purpose, relationship between a 3 stride of AMBJ distance and a cross section area of psoas major muscle were analyze. By using random sampling, 10 older men were sampled as subject who participate Gate-ball club in S-Gu, D-metropolitan city. Analysis of relation between the 3 stride of AMBJ and psoas major muscle scale recorded by MRI of older men were executed. Results of the analysis could be summarized as the following. 1) In the case of older men, the male who has much muscle weight and large thigh girth has big cross section area of psoas major muscle. 2) Relation among 3 stride of AMBJ, muscle weight(r=.822, p<.01), and thigh girth(r=.720, p<.05) especially, cross section area of psoas major muscle presented very high correlation(r=.91, p<.001). 3) Based on the analysis, measurement result of the 3 stride of Taekwondo Apkubi Momtong Bandae Jireugi was very effective diagnostic method to assume for health related to muscle strength level and all the muscular strength level of older men.

그레이브스병에서 치료에 따른 폐동맥압의 변화

남택만,조한수,이진서,송영림,김두만,두영철,박철영,정인경,홍은경,이성진,오기원,김현규,유재명,최문기,유형준,박성우 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.5

연구배경: 갑상선기능항진증에 의한 갑상선중독증 환자들은 호흡곤란을 호소하며, 그 원인으로 호흡근의 근력 약화, 좌심실부전으로 인한 폐모세혈관의 울혈, 기도저항의 증가, 갑상선종으로 인한 기관의 압박, 호흡기능 이상 등이 거론되고 있다. 폐동맥고혈압이 동반된 그레이브스병 환자가 여러 증례가 보고되었으며, 폐동맥고혈압 환자에게서 갑상선 자가항체와 갑상선기능저하증의 빈도가 높음이 알려지면서 갑상선중독증이 동반된 그레이브스병 환자에게서 관찰되는 호흡곤란의 한 원인으로 폐동맥압 증가가 작용할 가능성이 제시되고 있다. 이에 저자 등은 그레이브스병 환자를 대상으로 폐동맥압을 측정하고 치료 전후의 폐동맥압의 변화를 전향적으로 연구하였다. 방법: 갑상선중독증이 동반된 그레이브스병 환자와 정상 갑상선기능을 나타낸 대조군을 대상으로 갑상선기능검사 및 갑상선 자가항체를 측정하고, 심초음파를 이용하여 치료 전후로 폐동맥압을 측정하여 폐동맥압과 갑상선기능 및 갑상선 자가항체와의 관계, 폐동맥압의 변화 등을 관찰하였다. 결과: 1. 연구대상은 대조군 10명 (남녀비 1:9, 관해 상태의 그레이브스병 3명, 갑상선종 3명, 정상인 4명), 그레이브스병 환자 26명 (남녀비 7:19)이었다. 2. 대조군과 치료 전 그레이브스병 환자의 폐동맥압은 각각 23.5±2.32 mmHg, 29.6±10.3 mmHg이었고, 치료 전의 폐동맥압과 혈청 갑상선자극호르몬 결합억제 면역글로불린 (TBII) 농도는 유의한 양의 상관관계를 보였다. 3. 26명의 그레이브스병 환자 중에서 10명 (38.5%)이 폐동맥고혈압 (기준: 폐동맥압 > 30 mmHg)으로 진단되었다. 4. 치료 전후로 폐동맥압을 측정한 13명은 폐동맥압이 치료 전 29.6±10.3 mmHg에서 치료 후 폐동맥압 22.2±6.48 mmHg로 의미있게 감소하였다. 결론: 갑상선중독증을 보이는 그레이브스병 환자의 약 40% 정도에서 폐동맥고혈압이 발견되어 폐동맥고 혈압은 그레이브스병에 흔하게 동반하는 질환으로 생각된다. 향후 그레이브스병 환자에서 관찰되는 폐동맥압의 증가와 관련한 병인, 발생기전 및 임상적 의의 등에 대한 연구가 필요할 것으로 생각된다. Background: Exertional symptoms, dyspnea and impaired effort tolerance are common in patients with Graves' disease. Proposed explanations include: high-output left heart failure, ineffective oxygen utilization and respiratory muscle weakness. In addition, pulmonary hypertension has also been reported in patients with Graves' disease. A high prevalence of hypothyroidism and positive thyroid autoantibody were also observed in patients with pulmonary arterial hypertension. Therefore, the pulmonary artery pressure in patients with Graves' disease was evaluated. Methods: Two-dimensional and Doppler echocardiographic examinations (Hewlett Packard Sonos 2500) were performed to determine the pulmonary artery (PA) pressure in 26 Graves' disease patients, both before and after treatment (23 patients with propylthiouracil and 3 with RAI), and in 10 euthyroid controls. The changes in the PA pressure after treatment were evaluated in 13 patients with Graves' disease, who became euthyroid after treatment. Results: The pulmonary artery pressure was increased in the untreated Graves' disease patients compared to the normal controls (23.5±2.32 vs. 29.6±10.3 mmHg). 38.5% of the Graves' disease patients (10/26) showed pulmonary arterial hypertension (PA>30 mmHg) and the serum TBII level was higher in the Graves' disease patients with pulmonary arterial hypertension than in those with normal PA pressure (P<0.05). In the Graves' patients who became euthyroid after treatment, the PA pressure was significantly decreased. Conclusion: 38.5% of the untreated Graves' disease patients showed pulmonary arterial hypertension, and the pulmonary artery pressure was significantly decreased in those who became euthyroid after treatment. The pathogenesis and clinical importance of pulmonary arterial hypertension in Graves' disease requires further studies (J Kor Soc Endocrinol 18:465∼472, 2003).

다발성 말초신경병증의 조기진단 : 적외선 체열촬영검사와 전류지각역치검사의 조합진단 Combination Diagnosis Using by Digital Infrared Thermogram and Current Perception Threshold

이삼규,김재형,최인성,이소영,한재영,조성렬,김재휴,노성만,정민영,정동진,김현성 全南大醫大 2001 전남의대학술지 Vol.37 No.3

부신피질 호산성 과립세포종 1예

이성진,이호권,박철영,정인경,홍은경,오기원,김현규,김두만,유재명,임성희,최문기,유형준,박성우 대한내분비학회 2004 Endocrinology and metabolism Vol.19 No.1

저자들은 건강검진에서 시행한 복부 초음파검사상 우연히 좌측 부신 종괴가 발견되어 복부 전산화 단층 촬영검사와 호르몬검사를 시행한 후 부신피질 악성종양과의 감별 진단을 위해 부신절제술과 전자현미경검사를 포함한 병리조직학적 검사를 시행하여 부신피질호산성 과립세포종으로 진단한 증례를 경험하였기에 문헌고찰과 함께 이를 보고하는 바이다. Oncocytomas are neoplasms, histologically are composed of epithelial cells, with abundant, acidophilic and granular cytoplasm. Electron microscopic studies of oncocytomas have shown that the cytoplasm of oncocytes is packed with mitochondria. The adrenal gland is a very rare anatomical site for oncocytomas, and to the best of our knowledge, only thirty-six cases of adrenal oncocytomas have been described. Herein, a case of a large adrenal mass in a forty-year-old man, which was incidentally detected by abdominal ultrasonography, is presented. This patient demonstrated no clinical manifestation associated with adrenal hyperfunction. Hormonal studies showed no abnormal findings, except for a mild elevation of the 24-hour urinary VMA level. Abdominal computed tomography with enhancement revealed a large, well-defined left adrenal mass, measuring 5.0×4.2 ×3.0 cm. The patient underwent a left adrenalectomy, and a light microscopic examination confirmed an adrenocortical oncocytoma, with characteristic oncocytes and polygonal, abundant, eosinophilic and granular cytoplasm. The tumor cells were positive for cytokeratin and vimentin as well as S-100, but negative for chromogranin on immunohistochemical staining. An electron microscopic examination demonstrated closely packed mitochondria, containing intramitochondrial inclusions. After surgery, there was no evidence of a recurrent or distant metastatic disease at the 5 month follow-up. In summary, an extremely rare case of a man with an adrenocortical oncocytoma is reported, which was confirmed by histological examinations, including electron microscopy (J Kor Soc Endocrinol 19:82∼89, 2004).

가토의 뇌동맥류 모형에서 모동맥 및 동맥류 협자에 따른 동맥류 내압의 변화 :기초 연구

김은영,송준혁,김명현,박향권,김성학,신규만,박동빈 대한신경외과학회 1999 Journal of Korean neurosurgical society Vol.28 No.4

헬름홀츠 코일을 이용한 강자성체의 와전류검사

성제중,서동만,신용훈,엄태건,서동섭 한국비파괴검사학회 2003 학술대회 논문집 Vol.- No.1

Ferromagnetic material like the steel tubes can easily distort eddy current testing signal due to increased magnetic permeability for defects. Because magnetic field of the test probe is affected in an inconsistent way when the material under the testing has permeability. This permeability effect can be reduced by magnetic saturation. In this paper eddy current testing system was developed to detect flaws on the steel tubes. Magnetic saturation probe with helmholtz coil was designed for saturation and inspection of the steel tubes. When using the designed test probe, the relationship between flaw signals and noises was obviously discriminated. Additionally, a high pass filter was included in the eddy current board to minimize noises due to DC magnetic field.

InSb化合物 半導體에 있어서의 諸效果와 그 活用性에 관한 硏究 : 高周波效果를 中心으로

成萬永 단국대학교 1984 論文集 Vol.18 No.-

This paper describes studies on various fundamental effects related to the magnetoresistive effects in InSb, of which electron mobility is known to be the highest in semiconductors. The main purpose of this paper is to contribute to a better understanding of the characteristics of the magnetoresistive devices from an engineering point of view, and then promote the development of their new application fields. The magnetoresistive effect is an effect in which a semiconductor element changes its electric resistance when a magnetic field is applied to it. The resistance change between to current electrodes is attributed to the change in the current flow in the element and the change in the resistivity. The former is a phenomenological effect and is called the geometrical effect, since it is great influenced by the geometrical configuration of the element. The latter is a magnetic field dependence of the resistivity and is called the magnetoresistivity effect or the physical magnetoresistance. In this paper, the magnetoresistive effects at a high frequency are described. Theoretical calculation has been made on high frequency transport properties of InSb under a d.c. magnetic field, leading to a conclusion that the relative increase of microwave loss in InSb under a magnetic field, γ_1 is given by γ_0{1+ω(τ_e+τ_h)}, where γ_0 is the relative resistivity increase Δρ/ρ_0 under a d.c. magnetic field with d.c. current, and γ_e and γ_h are the relaxation time for electrons and that of holes respectively. Measurements were made on the microwave power loss at 34㎓ at room temperature under magnetic fields up to 1.5 Telsa. The experimental results show an appreciable influence of ωτ on the loss even at room temperature as predicted by the theory. The influence of the surface roughness and geometry at 34㎓ has also been investigated experimentally. It has been found that these effects play an important role in high frequency properties in InSb under a magnetic field.

半導體素子의 高周波特性 向上策 樹立을 위한 새로운 電界效果 트랜지스터의 開發에 관한 硏究

成萬永 단국대학교 1982 論文集 Vol.16 No.-

A technique has been proposed for fabricating a submicronchannel Vertical V-groove field effect transistor (V-groove FET) using silicon batch processing techniques and standard photolithgraphy. The short channel length of this device is expected to make it useful for microwave applications as well as for high speed integrated circuits. The fabrication procedure is easily modified for use with compound semiconductors to take advantage of the higher mobilities and greater carrier velocities available in other materials. The fabrication procedure makes use of an anisotropically etched V-groove into a (100)p type silicon region grown on an n-silicon substrate to delineate the source of the Junction type V-groove FET. The V-groove etch is designed to be selfterminating when the distance from the bottom of the groove to the pn junction interface reaches a specified submicron value. The distance will be the channel length of the completed junction type V-groove FET. A subsequent donor diffusion into the surface of the etched groove creates the n-type channel between the source and the substrate. Metal contact at the surface of the p-region serves as the gate terminal while contacts at the V-groove surface and the substrate form the source and drain terminals, respectively. A finite-element numerical simulation of the junction type V-groove FET operation was performed using a FORTRAN program run on a Cyber-174 computer. The program alternaly solves Poisson's equation and the electron and hole continuity equations over the region of interest with mixed Dirichlet and Neumann boundary conditions until a steady-state solution is reached Low-frequecny output characteristics of the device were deduced by varying the gate and drain voltage boundary conditions over many program runs. A technique was proposed for fabricating the p n V-groove JEFT structure. This technique would utilize an anisotropic etch through a p-region into the n-substrate followed by an n-type epitaxial regrowth step in the faces of the V-groove to create the V-groove FET channel. The numerical simulation predicts a higher transconductance for this structure. The lack of adequate epitaxial facilities precluded the fabrication and evaluation of such a structure. As the results of the experimental fabrication, the microwave V-groove FETs are obtained. The cut off frequencies are calculated to be 56㎓ by Linvill's power gain equation using the measured capacitance and transconductance.