Coevaporation에 의한 cd₁-xZn_(x)S 박막 제작 및 특성에 관한 연구

李載亨,李虎烈,朴鏞冠,申成浩,申載爀,朴光子 성균관대학교 1998 학술회의지원논문목록집 Vol.1998 No.-

In this paper, structural optical and electrical properties of Cd_(1-x)Zn_(x)S thin films prepared by coevaporation method were studied. Also, effects of ZnS mole ratio(x) to CdS on properties of thin film Cd_(1-x)Zn_(x)S/CdTe solar cells were investigated. When the ZnS mole ratio was less than 0.85, the crystal structure of Cd_(1-x)Zn_(x)S films was hexagonal with the c axis aligned perpendicular to the substrate. For x>0.85, however, the Cd_(1-x)Zn_(x)S films were grown with cubic zincblende structire. As the ZnS mole ratio increased the lattice constant of Cd_(1-x)Zn_(x)S films rapidly increased with ZnS mole ratio. The open circuit voltage of Cd₁xZnxS/CdTe solar cells increased with x due to reducing of the electron affinity difference between Cd₁xZnxS and CdTe films. However, the increase of series resistance due to the high resistivity of Cd_(1-x)Zn_(x)S films results on reducing conversion efficiency.

Induction of heme oxygenase-1 protects against podocyte apoptosis under diabetic conditions

Lee, Sang Choel,Han, Seung Hyeok,Li, Jin Ji,Lee, Sun Ha,Jung, Dong-Sub,Kwak, Seung-Jae,Kim, Seung Hye,Kim, Dong Ki,Yoo, Tae-Hyun,Kim, Jin Hyun,Chang, Se-Ho,Han, Dae Suk,Kang, Shin-Wook International Society of Nephrology 2009 Kidney international Vol.76 No.8

Heme oxygenase-1 (HO-1) is an anti-oxidant enzyme normally upregulated in response to oxidant injury. Here we determined the role of HO-1 in podocyte apoptosis in glomeruli of streptozotocin-treated rats and in immortalized mouse podocytes cultured in media containing normal or high glucose. HO-1 expression, its activity, the ratio of Bax/Bcl-2 protein, and active caspase-3 fragments were all significantly higher in isolated glomeruli of diabetic rats and in high glucose–treated podocytes. These increases were inhibited by zinc protoporphyrin treatment of the rats or by HO-1 siRNA treatment of the podocytes in culture. The number of apoptotic cells was also significantly increased in the glomeruli of diabetic rats and in high glucose–treated podocytes. Inhibition of HO-1 accentuated the increase in apoptotic cells both in vivo and in vitro. Our findings suggest that HO-1 expression protects against podocyte apoptosis under diabetic conditions.

심상성 루프스에서 Nested-Primer Gene Amplification Assay에 의한 결핵균 DNA의 검출

신문석,전효진,김병천,이규석,김재룡,권호준,송준영 啓明大學校 醫科大學 1994 계명의대학술지 Vol.13 No.4

Lupus vulgaris, which is a progressive form of postprimary tuberculosis in patients with a moderate to high degree of immunity and tuberculin sensitivity, is the most common, most serious, and most variable type of cutaneous and mucous membrane tuberculosis. Domonstration of M.tuberculosis directly or in culture in some of these eruptions can be difficult. It is essential to demonstrate the presence of M.tuberculosis in a clinical sample for a definitive diagnosis of tuberculosis. With the discovery of the polymerase chain reaction (PCR), the DNA diagnostic approach for infection has developed in a short period. With the dual purpose of definitive and rapid diagnosis of tuberculosis, this study examined the usefulness of a nested PCR for detection of M. turberculosis. Compared with a single-step PCR, the two-step PCR was able to enhance sensitivity approximately 1,000-fold on the basis of bacterial counts and DNA quantity. We concluded that two-step nested PCR appeared to be the most useful PCR protocol for early and sensitive diagnostic method detecting M.tuberculosis in acid-fast stain negative specimens.

AES-128 Rijndael 암·복호 알고리듬의 하드웨어 구현

신성호,이재흥 한밭대학교 정보통신전문대학원 2004 정보통신전문대학원 논문집 Vol.2 No.1

본 논문에서는 미국 국립표준기술연구소(NIST)에서 채택한 차세대 암호 표준인 Rijndael 암호 알고리듬을 하드웨어로 구현한다. 효율적인 연산을 위해 라운드를 2개의 부분 라운드로 나누고 부분 라운드 간에 파이프라인을 사용하였으며, 1 라운드 연산시 평균적으로 5클록이 소요된다. AES-128 암호 알고리듬을 ALTERA PPGA를 사용하여 하드웨어로 구현 후 성능을 분석하였다. 구현된 AES-128 암호 알고리듬은 암·복호화시 최대 90 Mhz의 동작 주파수와 약 230 Mbps의 암·복호율을 얻을 수 있었다. In this paper, Rijindal cipher algorithm is implemented by a hardware. It is selected as the AES(Advanced Encryption Standard) by NIST. The processor has structure that round operation divided into 2 subrounds and subrounds are pipelined to calculate efficiently. It takes 5 clocks for one-round. The AES-128 cipher algorithm is implemented for hardware by ALTERA FPGA, and then, analyzed the performance. The AES-128 cipher algorithm has approximately 230 Mbps encryption·decryption rate for 90Mhz max clock frequency.

전자빔으로 전처리한 제지폐수의 처리특성

신경숙,박재규,강호 忠南大學校 環境問題硏究所 1998 環境硏究 Vol.16 No.-

Treatability test for paper-mill wastewater pretreated with electron beam irradiation was investigated using the activated sludge simulation. The dose of electron beam irradiation exposed to paper-mill wastewater was relatively low(1kGy). The results showed that the BOD/CODCr of irradiated paper-mill wastewater increased up to 0.45 from 0.36 of unirradiated one. This was due to the conversion of nonbiodegradable organics to biodegradable ones by electron beam exposure. For the activated sludge systems operated at the various HRTs, BOD removal efficiency and COD removal efficiency of both reactors were similar. As a tool of sludge bulking measurement, sludge volume index(SVI) of activated sludge system operated with irradiated paper-mill wastewater was found to be lower (about 210∼ 241㎖/g)than that with unirradiated paper-mill wastewater(about 249∼298㎖/g). Biokinetic constants derived from Ekenfelder's modified model appeared 8.72/day for the irradiated paper-mill wastewater and 4.95/day for the unirradiated paper-mill wastewater, respectively. From the above results, it concluded that the pretreatment of paper mill wastewater with electron beam irradiation could improve the biodegradability as well as sludge activity even with the relatively low dose of electron beam irradiation.

통신용 정류기 시스템의 모델링 및 제어기 설계

신병철,송의호,양재석 國立 昌原大學校 産業技術硏究所 1999 産技硏論文集 Vol.13 No.-

This paper deals with the design of controller which is used to rectifier for communication. Mathematical small-signal modeling and characteristic analysis are performed about DC/DC converter and three-phase AC/DC converter. Bode plots are obtained by the mathematical small-signal modeling. By the PSpice simulation, performance of the controller is proved respectively in line regulation and load.

국내산고령토정제에 관한 연구

신건철,이재장,전호석,조성백 江原大學校 産業技術硏究所 1990 産業技術硏究 Vol.10 No.-

The samples used for this work were low grade clay(Fe?O? : 2.90%, TiO? :1.65%) produced from Youngsan-do district, and for the iron-bearing impurities removal having a bad influence on Kaoline sample was carried out column floatation using Oleic acid, Potassium oleat, Aero 840 promotor, Aero 870 promotor and Keroseneas collectors. For removal of the iron-vearing impurities from the kaoline, investigated first chemical composition size distribution of Kaoline sample, also performanced a basic study on pulp density, collector and pH change on a sort frother. The flotation separation of impurities from kaoline can be achieved by using both oleic acid and Aero 840 promotor as collectors within narrow aoid limits(pH 2-3). Pine oil was more effective frother than MIBC with olelic acid as aa collector.

LaCrO_(3) 후막의 가스 감도 특성

신정호,장재영,김정규,박기철 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

LaCrO_(3) thick film sensors were fabricated on an alumina substrate by screen printing method. The sensitivities for gases were investigated by varying the heat treatment temperatures of the films. The sensitivities of LaCrO_(3) thick film for Gallo and NH_(3) gases were better than for CO and NO gases. The best condition of heat treatment was 450℃ and the optimal operating temperature of LaCrO_(3) thick film for the highest sensitivity was 400℃. Sensitivities of LaCrO_(3) thick films about at 3000ppm for C_(4)H_(10) and NH_(3) gases were 85% and 95%, respectively.

Chiari malformation 환아에서 상악 구치부의 부유치

신은영,최병재,이제호,손흥규 大韓小兒齒科學會 2001 大韓小兒齒科學會誌 Vol.28 No.4

Chiari malformation은 하부 뇌간과 소뇌가 대공 속으로 들어가 하향 편위의 소견을 보이는 중추 신경계의 기형으로 3가지 type으로 분류된다. 본 증례는 7세 10개월 된 여환이 10일전부터 칫솔질시 상악 우측 어금니가 아프고 얼굴이 약간 붓고 아프다는 주소로 내원하였는데, 임상구강검사결과 상악 우측 제1대구치 원심에 치은낭이 형성되어 있었고 동요도와 동통이 존재하였다. 악골 방사선사진검사결과 상악 구치부의 골밀도가 정상에 비해 낮으며, 특히 좌우측 제1대구치 하방의 골의 부재가 보였다. 유년성 치주염의 가진 하에 치주치료 중 전신질환과의 연관성 문진으로 Chiari malformation의 의과적 병력을 확인한 후 3차원 전산화단층촬영을 시행하였다. 두개골이 전반적으로 얇으며 다수의 골결손이 관찰되고 대공이 다소 커져있으며 후두골과 상악골의 골밀도가 감소되어 있었고 특히 상악 구치부의 치조골이 거의 없어 상악 좌우측 제1대구치가 부유치처럼 보였다. 이에 본원 신경외과로 협의진료를 의뢰하여 계속적으로 관찰하고 있는 중이다. 소아에서 치주염이 의심될 때 leukemia, hystiocytosis X, hypoposphatasia등의 잠재된 전신질환과 연관되어 있을 수 있으므로 적절한 검사를 시행해야 하며 전신질환의 근본적인 원인을 치료할 수 있도록 고려해야 한다. The Chiari malformation is a deformation within the central nervous system which the lower brain stem and the cerebellum migrate into the foramen magnum causing herniation. In 1891, Arnold Chiari classified such symptoms into 3 categories. This case report is of a 8-year-old female with the complaint of a slight facial swelling and pain on the upper right molar during tooth brushing since 10 days before. Clinical examination showed gingival pocket formation on distal of the upper right first molar with pain and mobility of the tooth. Radiographic examination showed generalized low bone density in the upper molar area, and especially no bone support above the upper right and left first molars were noted. With a temporary diagnosis of Early-onset periodontitis, consultations with medical doctors for the possibility of an underlying systemic disease were made during periodontal treatment. 3D CT was taken with after a final diagnosis of Chiari malformation. Genralized thinning and defect of the cranial bone was noted and the foramen magnum was slightly enlarged. The occipital and maxillary bone was low in density, and the alveolar bone of maxillary posterior teeth was especially almost non-existing causing the upper right and left first molar to be floating. For this, the patient went under consultation with the department of neurosurgery and is still under observation. Periodontitis in childreren is very rare. When symptoms of periodontitis appear in a child, due to the possibility of an underlying systemic disease such as leukemia, histiocytosis X, and hypophosphatasia, proper examinations should be carried out so that the primary factor the symptoms can be treated.

몰리브덴이 첨가된 Stellite 6 합금의 마모와 부식특성

申種喆,金在洙,李德悅,梁在雄,尹珍國,盧大虎,李種權 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.10

Hardfacing layers of Stellite 6 with different molybdenum content are deposited on AISI 1045-carbon steel using Plasma Transferred Arc welding(PTA) machine. The microstructures, wear and corrosion resistances of the hardfacing layer are investigated in order to clarify the effect of molybdenum in Stellite 6 alloys. The microstructural characterizations of the hardfacing layers are performed using X-ray diffraction, back scattered electron images, and scanning electron microscopy. With an increase of Mo contents, M_6C type carbide are formed instead of Cr-rich type carbides, and so this microstructural change enhanced the mechanical properties such as wear and corrosion resistance of a Mo-modified Stellite 6 alloy.