• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.874-879
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• 1995

Magnetic properties of FeMoN, FeMoTaN, FeTaN and FeTaC films deposited by DC magnetron reactive sputter were investigated, and correlated with their microstructure. FeMoN films were not showen the soft magnetic prop¬erties, because of generated $Fe_{2}Mo$, $Fe_{3-2}N$ and $Fe_{4}N$ phases. Ta added films, however, effectivly retarded the $\alpha$-Fe grain growth and suppressed the generation of Fe nitrides or carbides during heat treatement. The soft magnetic properties of $B_{s}:15\;kG,\;H_{e}:0.25\;Oe,\;\mu':4000(at\;5\;MHz),\;and\;B_s:14.5\;kG,\;He:0.25\;Oe,\;\mu':2700(5MHz)$ were observed in $Fe_{78.8} Ta_{8.5}N_{12.7}\;and\;Fe{75.6}Ta_{8.1}C_{16.3}$ films, respectively.

• Journal of Chest Surgery
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• v.29 no.6
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• pp.614-620
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• 1996

The method of treatment in lung cancer patients with invasion to parietal pleura, diaphragm, peri- cardium or vertebra is controversial, and resection of these invasion together with pneumonectomy is called "complex pneumonectomy" From March 1990 to February 1994 we performed 18 cases of "complex pneumonectomy". Seven patients had resection of chest wall, 10 patients had pericardial re- section, and one patient had resection of diaphragm Right pneumonectomy was done in 8 cases and left pneumonectomy was done in 10 cases. The age of patients were from 40 to 70 years(mean 58 years) with male to female ratio of 17 to 1. The chief complaints of the patients on admission were cough (13), dyspnea on exertion (11), chest pain (10), weight loss (9), general fatigue (9), and sputum production (4 . Postoperative pathology were 13 squamous cell carcinoma, 3 adenocarcinoma, and one case each of adenosquamous carcinoma and small cell carcinoma. The postoperative pathologic stages were 2 T3NO MO, 4 TIWIMO, 6 T3N2MO, 5 T4N2MO, and 1 TIWIMO. There was one operative mortality(5.5%). Excluding one follow up loss, 14 patients expired during the follow-up and the mean survival was 9.07 $\pm$ 4.82 months. One patient with stage TINOMO who had chest wall resection is alive at 35 months follow-up and a patient with T3N2MO who had diaphragm resection is alive at 36 months follow-up. Therefore, selection of patients for "complex pneumonec- tomy" is very important, and a long term survival is possible.ong term survival is possible.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.36-39
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• 2004

There are a lots of merits in PLS(Plasma Lighting System). But it is not widely used because the price is too high though it has very quality and efficiency. So it is necessary to develop a PLS which can be widely used with its merit.

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.257-259
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• 1991

• Korean Journal of Materials Research
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• v.12 no.10
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• pp.825-830
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• 2002

The growth rate of solid grains in TiC-XC-2vol% and TiC-XC-30vo1% Ni cermets, where X=Zr, W or Mo, was fitted to an equation of the form $d^3$-$do^3$=Kt. The grain growth behavior during liquid phase sintering at 1673K decreased markedly with addition of $Mo_2$C or WC and increased with addition of ZrC. The contiguity ratio was greater in the alloys with smaller growth rate constant and decreased with increasing Ni content in the $TiC-Mo_2$C-Ni cermet. The grain growth mechanism could be explained by the effect of contiguous grain boundaries in restricting the overall grain growth.

• Structural Engineering and Mechanics
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• v.44 no.5
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• pp.601-609
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• 2012

Effect of different crack sizes on fracture criterion of some engineering materials was investigated in this work. Using finite element (FE) method coupled with a newly developed algorithm, J-integral values for different crack sizes were obtained for single-edge notched bend (SENB) and compact type (CT) specimen. Specimens with initial a/W ratio from 0.25 to 0.75 varying in crack size in steps of 0.125 were investigated. Several different materials, like 20MnMoNi55, 42CrMo4 and 50CrMo4, usually used in engineering structure, were investigated. For one of mentioned materials, numerical results were compared with experimental and their compatibility is visible.

• Journal of Welding and Joining
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• v.13 no.4
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• pp.103-112
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• 1995

This study was performed to optimize friction welding conditions of Cr-Mo steel bars used for hydraulic of pneumatic valve spools and to realize the real-time evaluation of weld quality by acoustic emission method. SNCM220, SCM435, SCAM645, and SCM415 steel bars were tested to find optimum conditions of friction welding. Auantitative equations which exhibit the relations of tensile strength, elongation, reduction of area and energy absorption with friction heating time were obtained by the experiment. Acoustic emission was also performed in the friction weldig process, and the real-time evaluation was enabled to find the optimum range of weld strength. Finally, the strength and toughness of welded joints were interpreted by the sem analysis of tensile fracture surfaces.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.210-215
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• 2001

The ferritic 2.25CrMo steel has been used for high temperature structure applications such as turbine rotors, boilers and pressure vessels in fossil plant and petroleum chemical facilities. However, this steel is known to result in aging degradation due to temper embrittlement, carbide induced brittleness and softening of matrix after long time exposure to high temperature. This research investigated the microstructural and mechanical changes after artificial degradation treatment and evaluated the degree of degradation by several nondestructive methods. The decrease of electrical resistivity and increase of magnetic Barkhausen noise(RMS voltage) with increasing aging time were observed. The change of electrical resistivity and Barkhausen noise showed a good correlation with the ductile-brittle transition temperature.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.499-501
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• 2005

지휘통제, 전략전술, 물자관리 등 다양한 분야에서 사용되는 국방정보시스템들은 필요에 따라 원활하게 상호운용 되어야 군 정보화 효과를 극대화할 수 있다. 이 논문은 정보시스템 상호운용 수준(LISI)에 의거해서 국방정보시스템 간의 상호운용 능력을 전자설문 방식으로 측정하고 테스팅을 통해서 확인하는 기법을 제시한다. 제시된 전자설문 기법은 구현옵션 집합과 질의문을 이용해서 정보시스템 간의 잠재적 상호운용 수준을 측정한다. 반면에 테스팅 기법은 전자설문을 통해서 결정된 두 정보시스템 간의 잠재적인 상호운용 수준을 분산 소프트웨어 테스팅 기법을 사용하여 실질적으로 측정한다. 마지막으로 제시된 전자설문 기법과 테스팅 기법을 바탕으로 개발된 상호운용성 평가도구를 소개하고 적용결과를 제시한다.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3225-3227
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• 2010

The thermal conductivity of layered metal chalcogenides such as $MT_2$ (M = Mo, W; T = S, Se) shows a marked decrease after exfoliation and subsequent restacking process. Random stacking of two-dimensional crystalline sheets circumvents thermal conduction pathways along a longitudinal direction, which results in a reduction in thermal conductivity. $WS_2$ and $WSe_2$ compounds retain p-type conducting behavior after exfoliation and restacking with decreased electrical conductivity due to the change in carrier concentration. $MoSe_2$ compound exhibits metallic behavior < $130^{\circ}C$ with a small Seebeck coefficient, which results from metastable 1T-$MoSe_2$ structure of the restacked phase.