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71.
Kyoung Hwan Yeo Chang Woo Oh Sung Min Kim Min Sang Kim Chang Sub Lee Sung Young Lee Sang Yeon Han Eun Jung Yoon Hye Jin Cho Doo Youl Lee Byung Moon Yoon Hwa Sung Rhee Byung Chan Lee Jeong Dong Choe Ilsub Chung Donggun Park Kinam Kim 《Electron Device Letters, IEEE》2004,25(6):387-389
Highly manufacturable partially insulated field-effect transistors (PiFETs) were fabricated by using Si-SiGe epitaxial growth and selective SiGe etch process. Owing to these technologies, pseudo-silicon-on-insulator (SOI) structures, partially insulating oxide (PiOX) under source/drain (PUSD) and PiOX under channel (PUC), could be easily realized with excellent structural and process advantages. We are demonstrating their preliminary characteristics and properties. Especially, in the PUSD PiFET, junction capacitance, leakage current, and DIBL in bulk devices could be reduced and the floating body problem in SOI devices was also cleared without any area penalty. Thus, this PiFET structure can be a promising candidate for the future DRAM cell transistor. 相似文献
72.
KC Park KH Kim SW Youn JH Hwang KH Park JS Ahn YG Kim SD Kim DY Lee JH Choe JH Chung KH Cho 《Canadian Metallurgical Quarterly》1998,139(6):1087-1091
Bowenoid papulosis (BP) of the genitalia, characterized by the histological findings of a squamous cell carcinoma, follows a largely benign clinical course. The detection of oncogenic human papilloma viruses (HPV) from BP points to an aetiological role of these viral infections. A 47-year-old man with multiple genital skin lesions was seen over a 10-year period with the diagnosis of BP. Recently, he attended again with a recurrent genital tumour that was diagnosed as squamous cell carcinoma. His genital lesions progressed and became polymorphic in appearance, from a wart-like tumour to a reddish invasive plaque. To screen for the presence of different HPV sequences from different skin lesions and to correlate each HPV type with distinct clinical manifestations, polymerase chain reaction and single-strand conformational polymorphism (PCR-SSCP) were performed. PCR-SSCP revealed the presence of several types of HPV from different genital lesions. Sequencing results disclosed that he had a mixed infection of HPV6b, HPV16, HPV18 and HPV33, respectively. Interestingly, the clinical findings were fairly well correlated with the oncogenic potential of HPV found from each lesion. 相似文献
73.
Y Lee JW Kim IA Lee HB Kang YK Choe HG Lee JS Lim HJ Kim C Park IS Choe 《Canadian Metallurgical Quarterly》1996,39(4):833-842
Considerable genomic microdiversity has been reported previously among Helicobacter pylori isolates. We have constructed genome maps of four unrelated H. pylori strains (NCTC11637, NCTC11639, UA802 and UA861) using pulsed-field gel electrophoresis (PFGE) with NotI and NruI, hybridization with extracted PFGE DNA fragments and probing with 17 gene probes. These strains of H. pylori were compared with a fifth unrelated H. pylori strain NCTC11638 mapped previously. Considerable diversity in gene arrangement was evident among the five H. pylori maps, and no consistent gene clustering was found. The association of only four genes, katA (catalase gene), vacA (vacuolating cytotoxin gene), hpaA (a putative adhesin gene), and pfr (bacterial ferritin gene) were generally conserved within approximately the same 25% of the genome; however, the order of these genes also varied. Our study demonstrates that macrodiversity, i.e. variability in gene order, in addition to microdiversity, is a characteristic of the H. pylori genome. 相似文献
74.
Tai-Su Park Hye Jin Cho Jeong Dong Choe Il Hwan Cho Donggun Park Yoon E. Jong Ho Lee 《Electron Device Letters, IEEE》2004,25(12):798-800
Body-tied triple-gate pMOSFETs were fabricated using bulk Si wafers and characterized. Process steps to implement the devices are explained briefly. Device characteristics of the triple-gate pMOSFETs were compared with those of the conventional planar channel device. While maintaining low off-leakage currents and threshold voltages similar to those of planar pMOSFETs in the parallel arrayed 30 000 transistors, the body-tied triple-gate MOSFETs showed about 74 mV/dec of subthreshold swing (92 mV/dec for conventional devices) and a drain-induced barrier lowering of 34 mV/V (92 mV/V for conventional devices). It was also addressed that I/sub SUB//I/sub D/ of the body-tied triple-gate is lower than that of the planar channel device. 相似文献
75.
Byung-Hak Choe Soo-Keun Shin Yeong Ouk Kim Yong-Teak Hyun Seung-Eon Kim Yong-Tai Lee 《Metals and Materials International》2005,11(5):365-369
This paper presents the finding of a microstructural abnormality generated in the metastable phase of a supersaturated state,
and compares the results with ordering behavior such as premartensitic transformation. A tweed structure consisting of the
metastable phase was observed by transmission electron microscopy, and spot satellites inflicted by streaks were also observed
in lattice diffraction. The present report also reviews a new phase transformation from the metastable phase caused by the
processes of aging, sub-zero quenching, and induced strain or stress. 相似文献
76.
The sequential changes of natural killer cell (NK) activity and prostaglandin E2 (PGE2) during hepatocarcinogenesis induced by diethylnitrosamine (DEN) in male Fischer 344 rats were investigated. DEN at a concentration of 40 ppm was administered in drinking water for 10 weeks. At weeks 5, 10, 20 and 30, rats were autopsied and the development of glutathione S-transferase placental form positive foci (GST-P+ foci) at weeks 5 and 10 and hepatocellular tumors at weeks 20 and 30 were examined. The labeling index of bromodeoxyuridine (BrdU) an indicator of DNA synthesis, was also sequentially checked. GST-P+ foci were found to increase with age. Hepatocellular nodules increased until week 20, but by week 30 when the incidence of hepatocellular carcinoma was 100%, the incidence of nodules had decreased. BrdU positive cells also increased with age, and by week 30 when the incidence of hepatocellular carcinoma was 100%, the number of BrdU-positive cells had decreased. NK cell activity increased until week 10, but at week 20, was less than in the untreated control group. The level of PGE2 increased until week 5, but at week 10, levels were not significantly different from those seen in the untreated control group. On the basis of these results, we concluded that NK activity is closely related to the progression of hepatocarcinogenesis, but PGE2 levels show no significant change. 相似文献
77.
We introduce a novel signal set defined over a signal space that consists of L (L/spl ges/2) orthogonal planes, and a quasi-synchronous trellis-coded code-division multiple-access (TC-CDMA) system based on it. The proposed scheme makes efficient use of the available processing gain to improve power and/or bandwidth efficiency for practical multiuser interference environments. Having a multiplanar signal constellation structure, the proposed scheme provides several options for a given required data rate, which makes it better adapted to dynamic channel conditions. Analytical bounds and simulation results indicate that at practical error rates and 2 b/s/Hz the proposed scheme is approximately 1.2 dB better than a TC-CDMA system based on 8-PSK, and 3 dB better at 3 b/s/Hz compared to TC-CDMA using 16-QAM. Additionally, the proposed system is approximately 1 dB better than a multicoded system using two signature sequences per user. 相似文献
78.
It is shown that an amplifier based on f.m. modulation of the frequency generated by a Josephson junction can have a very low-noise figure, and that it can handle voltages as small as 10?12 V. 相似文献
79.
80.