백서의 원위부 피편에 동맥유입의 중요성에 관한 실험적 연구

최규남,최희윤,강희문,김한중 大韓成形外科學會 1983 Archives of Plastic Surgery Vol.10 No.2

Microsurgery and myocutaneous flap have been developed recently for wide employment in plastic and reconstructive surgery. Therefore, the delay procedure has been declined in its use recently, because it has many difficult problems. If the flap is longer and larger, it should be delayed for complete survival, but delay requires considerable time. Therefore, as a substitute for delay, vascular anastomosis in the distal part of a flap will theoretically give the same effect. In this study, we investigated the importance of arterial inflow in the distal side of a flap in rats. The experiment was done in 3 different groups according to the design of flaps and in each group 3 subgroups were made. In A flap, the superficial epigastric artery was preserved or anastomosis. In V flap. the superficial epigastric vein was preserved or anastomosis. In C flap, as a control flap, both artery and vein were severed. In result, A flaps in all 3 groups were completely survived. Both V and C flaps in all 3 groups were showed distal necrosis. But C flaps were showed more necrosis than V flaps. In conclusion, we suggest the possibility that a large flap may be transposed in one stage with vascular anastomosis in the distal part-preferably artery and vein, or artery only.

심첨부 비후 심근증에서 심근 내 미세 관상동맥의 혈류 예비력 평가 : 경흉부 도플러 심초음파를 이용한 연구 Study Using Transthoracic Doppler Echocardiography

윤호중,박철수,신재원,임상현,조은주,정해억,전희경,오용석,정욱성,김재형,최규보,홍순조 대한순환기학회 2004 Korean Circulation Journal Vol.34 No.3

非晶質 Silicon 薄膜의 製作 및 그 Doping 效果

최범식,김수길,고년규,황정남,정원모,이철주 연세대학교 자연과학연구소 1982 學術論文集 Vol.9 No.-

SiH_4 기체에 PH_3 및 B_2H_6 기체를 0.7% 체적비로 혼합하여 rf glow 방전법으로 n형 및 p형 a-Si:H 박막을 기판온도 120℃에서 제작하여, 광투과도 측정, 열처리에 따른 전기 전도도의 변화 등을 조사하여 이들의 doping 효과를 연구하였다. n형, p형 및 undoped a-Si:H 박막의 optical gap은 각각 1.73eV, 1.86eV 및 1.86eV로 doping이 많이 이루어질수록 줄어 들었다. 250℃에서 열처리한 시료들의 상온에서의 전도도는 각각 2×10^-2Ω^-1㎝^-1, 5×10^-8Ω^-1㎝^-1, 5×10^-7Ω^-1㎝^-1이었고, 활성화 에너지 ??E는 각각 0.16eV, 0.49eV 및 0.48eV이었다. 300℃에서 열처리한 결과, ??E는 줄어 들고 전도도는 증가하였다. 350℃ 및 450℃에서 열처리한 결과 dehydrogenation 효과로 인하여 n형과 p형은 서로 상반되는 결과를 보였다. 즉, n형 시료의 전도도는 감소하고 ??E는 증가하였지만, P형 시료의 전도도는 증가하고 ??E는 감소하였다. 저온 영역에서 구한 n형 시료의 전도도로부터 hopping 활성화 에너지를 구한 결과 0.085eV이었다. Thin n-type and p-type a-Si:H films were prepared by rf glow discharge decomposition of silane mixed with 7×10^-3 parts per volume of phospine or diborane. All specimens were deposited on glass substrates held at 120℃. In order to determine the doping effects the opital absorption and dc conductivity of these specimens were measured after annealing at various temperatures. The optical gap was 1.73eV in the case of the n-type specimens, 1.80eV for the p-type, and 1.86eV undoped. This showed that the gap width decreased as the doping increased. The room temperatuer conductivities of these specimens annealed at 250℃ were 2×10^-2Ω^-1㎝^-1, 5×10^-8Ω^-1㎝^-1, and 5×10^-7Ω^-1㎝^-1, respectively, and the activation energies, ??E, of these specimens were 0.16eV, 0.49eV, and 0.48eV, respectively. For specimens annealed at 300℃, ??E decreased and the conductivity increased. When these specimens were annealed at 350℃ and 450℃, dehydrogenation caused opposite effects on the n-type and p-type specimens; the conductivities of n-type specimens decreased and ??E increased, but the conductivities of p-type specimens increased and ??E decreased.From an investigation of the temperature dependence of the conductivity of the n-type specimen in the low temperature region, we determined that the hopping activation energy was 0.085eV.

전자식 ballast의 시험용 의사부하에 관한 연구

이규대,이윤섭,최복길 公州大學校工科大學生産技術硏究所 1994 論文集 Vol.2 No.-

형광들을 점등시키는 안정기의 역할은 형광등과 같이 부저항특성을 갖는 방전등에 과전류가 유입되어, 파괴되지 않도록 일정전압 및 전류를 유지시켜주는 것이다. 최근 사용되고 있는 전자식안정기는 25-30KHz의 주파수를 사용, 캐패시터에 의한 안정화전류를 유도하고 있다. 그러나 전자식안정기는 고주파를 사용하는 관계로 제품의 품질보증을 위한 제반 규정이 까다로워 생산자는 개개의 안정기를 실제 형광등을 사용하여 특성검사를 하고 있다. 본 논문에서는 전자식안정기 특성검사의 효율성을 제고하기 위해 실제 형광등과 동일한 특성을 갖는 의사부하의 설계에 관하여 연구하였다. 초기의 과도 조건을 고려하지 않는 정전압 특성을 갖는 의사부하를 설계하여 실험한 결과 제한된 조건하에서 사용될 수 있음을 확인하였다. The electronic ballast has a role of taking a stable current of fluorescent lamp, which has a characteristics of negative resistance. Recently, it has been designed and operated on using the regulated constant current with capacitor and high frequency of 25 to 30KHz. But a fabricated electronic ballast in an assembly line was difficult to test, because it used a high frequency and needed strict provisions. And then manufacturer is now testing each ballast with a real fluorescent lamp. In this paper, we studied that real lamp can be replaced by a dummy load with the same characteristics.

物價變動會計 導入方案에 관한 硏究

李潤元,崔德圭,孫聖鎬 東亞大學校 1982 東亞論叢 Vol.19 No.1

The objective of financial reporting is assumed to provide informations regarding a firm's transactions and resources, which should be relevent to the making of economic decisiona by many persons or organizations inside and outside of the enterprise. The information of accounting should be useful in decision making but conventional historical cost acounting couldn't be relevant to this objective in current inflation period. The conventional historical cost accounting would be agreed on the assumption of a stable monetary value. There are some of problems in regarding the conventional accounting. First, historical cost accounting couldn't measure and communicate current values of corporate's assets and income. Second, the measurement of income is not relevant to information's users and rational in theoretical structure. Price-level changing has modified the meaning of income measured in terms of historical amounts. The income measured in terms of historical cost is consist of current operating income and earning by price level changing but it can't measure and communicate them separately. It is very difficult to maintain physical capital because the period income determined by matching historical cost and current revenue causes unadequate income tax and dividend. Now we are in the environment of changing prices. The conventional accounting couldn't provide the relevant information to the persons and organization inside and outside of the business no more than. In December 1974, the Financial Accounting Standards Board released on Exposure Draft which would have required supplementary financial statements prepared by a comprehensive restatement in terms of general purchasing power. In 1976. the Securities and Exchange Commission issued Accounting Series Release No. 190 requiring supplemental disclosure of the replacement cost of fixed assets and inventories for large corporations. In the United kingdom a government-sponsored committee (Sandilands Committee) on inflation accounting proposed that the historical cost accountng system should be scrapped and that current value accounting (primarily current replacement cost in practice) should be substituted. In 1980, FASB proposed supplementary statement that contains restating financial statement based on historical cost by general price-level and disclosing information of current replacement cost about the inventories and fixed assets. As you know, there are two kinds of inflation acounting models; general price-level accounting and replacement cost accounting. The latter is more relevant and reasonable than the former in accounting theory and the usefulness of informations. Replacement cost accounting has two major advantages in the presentation of significant financial information. First, the statement of financial position, under historical cost accounting, loses its economic significance when large price movements have rendered historical valuations virtually meaningless. But replacement cost valuation, however, does reflect the effect of changing price. Thus, replacement cost accounting generates a meaningful position statement. Second, because operating incomes are clearly separated from holding gains in replacement cost accounting system, it discloses more relevant information than the convention historical cost income statemennt. The efficiency of operations can be evaluated through referring to current operation income, and the effects of price changes are clearly identified as realizable cost savings which were either realized during the year or remain unrealized at the end of year. The flow of revenues, costs and cost savings in replacement cost accountings are as following: ?? I suggest that replacement cost accounting should be adopted urgently in Korea that has suffered serious inflation. In order to adopt inflation accounting in Korea, the followings should be set forth beforehead. First, Korean Acounting Association, the organization of accounting professors, or Korean Institute of Certified Public Accountant should suggest a public opinion about inflaion accounting. Second, accountants of firms should be reeducated of inflation accounting by accounting professors. Third, computers must come into wide use in almost of corporations to resolve the enormous operations of accounting. Forth, the policies of income tax and dividend must be changed. The base of income tax or dividend must not be corporation income (realized income) but current operating income.

CW Laser Annealing 과정중 SOS 상의 시간적 온도변화 측정에 관한 연구

고년규,윤희중,유동선,최원국,문경순 연세대학교 대학원 1987 延世論叢 Vol.23 No.1

The purpose of this experiment is to demonstrate the new method of TSRTM during CW Ar laser annealing using a He-Ne laser probe beam. Optical interference phenomena by a small changes of refractive index of Si, which is induced by the temperature change during short time laser annealing on the Si wafer surface, was used. The samples, SOS(Silicon on Sapphire), used in this work were epi. <100> Si grown on a <1012> insulator sapphire substrate with 2.0μm thickness. From the experimental temperature dependent equation of the refraction of index of Si with respect to the probe beam(λ=6328 Å) in furnace experiment, n(T)=3.98+7×10-4T (℃), the temperature on the destructtve or constructive interference was calculated. Incident Ar laser beam whose power ranges from 1.8W to 2.8W was irradiated and the effect of temperature rise of Si wafer on the elliptical spot whose major and minor axis is 200μm, 15μm respectively is investigated by the He-Ne laser probe beam which is focused 30μm. The annealing time ranges from 8 msec~250 msec to 500 msec~20 sec was adopted to estimate that the first constructive interference is occurred at least total irradiated power density 5.46×102Jㆍsec/cm2, and it is inferred that more than 180msec is needed for the first constructive interference when the total incident energy is 2.8 W. For the longtime annealing, about more than 1 sec, the interference pattern was coincided with the result produced by the furnace experiment. It is investigated from the space-resolved temperature gradient that the irradiated laser beam was focused in center.

저수축형 폴리머 콘크리트의 제조 및 물리·역학적 특성

연규석,이윤수,최동순,정경현,황진하 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

본 연구에서는 폴리머 콘크리트의 수축저감을 목적으로 수지량, 수축저감제함량과 S/a 비등을 변화시켜 경화수축의 변화와 강도 특성을 실험적으로 구명하였다. 경화수축량은 수치량이 105%일 때 보다 11.5%일 때, 즉 수지량이 증가할수록 커짐을 알 수 있었다. 수축저감제의 첨가에 따른 경화수축량은 감소함을 알 수 있었다. B10.5-SR10일 경우 수축저감제가 첨가되지 않았을 때 보다 약 30%, B10.5-SR20 일 경우 약 53%, B11.5-SR10일 경우 약 31%, B11.5-SR20 일 경우 약 47% 정도의 수축저감의 효과를 볼 수 있었다. S/a 비에 따른 경화 수축챨ㅇ은 S/a 60일 때 가장 적은 값을 보였으며, S/a 50, S/a 40 일때는 S/a60 일 때 가장 적은 값을 보였으며, S/a 50, S/a 40일 때는 S/a 60일 때 보다 각각 10%, 30% 정도 수축량이 증가함을 알 수 있었다. 압축 및 휨 강도특성은 수지량이 증가할수록 높아지고, 수축저감제의 첨가량이 증가할수록 낮아짐을 알 수 있었다. S/a 비에 따른 강도 특성은 압축강도와 휨강도 모두 S/a 비가 60일 때 가장 큰 값을 보였으며, S/a 비가 50,40 순으로 감소하였다. Many different polymer based concrete materials are known today, but the large setting or hardening shrinkage of polymer concrete is a problem to overcome in their practical applications. The setting shrinkage reaches about five to ten times the drying shrinkage of ordinary cement concrete, i.e, 50 to 60 ×10^4. This paper deals with a reduction in the hardening shrinkage of unsaturated polyester resin concrete which is treated with respect to shrinkage-reducing agent content, S/a ratio and catalyst content, and tested for length change during hardening, and flexural and compressive strengths. It is shown that the change of shrinkage-reducing agent content and S/a ration the length change of the unsaturated polyester resin concrete during hardening.

전자선 증착장치 및 ITO 박막의 제작과 그 특성에 관한 연구

김수길,최범식,우정주,고년규,황정남,정원모,이철주 연세대학교 자연과학연구소 1982 學術論文集 Vol.9 No.-

태양 전지의 제작시 투명 전극막으로 쓰이는 ITO 박막을 제조하기 위하여 cathode 접지 방식의 전자총을 가진 정전 편향 집속형의 전자선 증착 장치를 제작하였다. 가속전압이 0∼15kV, 필라멘트 전류가 0∼28A, 두 전극판 사이의 간격이 11mm, anode와 deflector 사이의 간격이 30mm인 최적 실험조건하에서 생성된 전자선 spot의 크기는 길이가 20mm 폭이 1mm였으며, 전자선의 출력은 약 400W였다. 이 전자선 증착 장치를 이용하여 1600℃까지의 증발 온도를 가진 도체와 절연체 등을 쉽게 증착시킬 수 있었으며, 만드어진 ITO 박막은 약 5000Å의 두께에서 10^-1∼10^-2Ω·㎝의 비저항과 95%의 광투과율을 갖는다. An electron beam evaporator with a cathode grounded type electron gun was designed and constructed in order to deposit ITO thin films for photovoltaic applications. The optimum condition was observed with electode spacing of 11mm, 30mm between anode and deflector, a cathode inner diameter of 3mm and an anode inner diameter of 5mm. As the accelerating voltage varies from 0 to 15kV and ghe filament current from 0 to 28 A, the minimum electron beam spot has a 20mm length, and 1mm width and the output power ranges from 0 to 400W under the above optimum conditions. We can deposit materials whose evaporation temperature is over 1600℃ using this evaporator. And as a result ITO thin film showed a low resistivity of 10^-1∼10^-2Ω·㎝ and the transmittance of 95%.

관상동맥질환자에서 경흉부 도플러 심초음파를 이용한 좌심실 확장기 기능의 평가 : 좌심실 확장기 장애 형태에 따른 분류

전희경,윤호중,유기동,박지원,전두수,정욱성,채장성,김재형,최규보,홍순조 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.1

심인성 색전 요인이 없는 뇌경색 환자에서 경식도 심초음파와 Acoustic Quantification을 이용한 대동맥 탄성의 평가

이종민,윤호중,임효영,박지원,김휘열,전희경,문건웅,정욱성,채장성,김재형,최규보,홍순조 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.8