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81.
Noda M. Matsue S. Sakai M. Sumitani K. Nakano H. Oku T. Makino H. Nishitani K. Otsubo M. 《Electron Devices, IEEE Transactions on》1992,39(3):494-499
The authors have realized 16-kb SRAMs with maximum address access time of less than 5 ns and typical power dissipation of less than 2 W at temperatures ranging from 25°C to 100°C. For the RAMs, they have developed a triple-level Au-based interconnection technology that reduces the wiring length and chip size of the SRAM so as to achieve high speed and high yield. Consequently, the wiring length and chip size are reduced to 69% and 58%, respectively, of those obtained by in previous work. The authors experimentally compared the delay time incurred by double-level interconnection and that by triple-level interconnection. This ratio is found to agree well with the simulated one by a model with distributed RC delay. After successfully suppressing Au hillock generation by lowering the process temperature, yield per wafer of 10% is obtained 相似文献
82.
K Uozumi N Ohno K Nakahara T Makino A Utsunomiya S Hanada T Arima 《Canadian Metallurgical Quarterly》1997,77(2):204-210
Differences in the responses of an elderly biracial group of cognitively normal subjects to a 15-item short version of the Boston Naming Test developed for the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) were examined. The subjects consisted of 103 Whites and 136 African Americans who were 70 years of age and older and living in a five-county urban and rural area of North Carolina. They were drawn from the Duke University site of the Established Populations for Epidemiologic Studies of the Elderly (EPESE). All were cognitively normal. With gender, years of education, and age controlled, White subjects performed significantly better than did African American subjects. The items in this test were selected to represent words with a high, medium, and low frequency of occurrence in English. They did not, however, show the expected gradation for either racial group. Medium and low frequency items were of comparable difficulty for the two races. Hierarchical ordering of difficulty would be improved with minor rearrangement of items. 相似文献
83.
Lipid hydroperoxide may react with protein or amino phospholipid without secondary decomposition. We prepared a polyclonal antibody to lipid hydroperoxide-modified proteins using 13S-hydroperoxy-9Z, 11E-octadecadienoic acid-modified keyhole limpet hemocyanin (13-HPODE-KLH) as immunogen. The antibody recognized 13-HPODE-modified bovine serum albumin (BSA), but not aldehyde-modified proteins, such as malondialdehyde-modified BSA. The antibody also recognized adducts derived from 13-HPODE and 13S-hydroperoxy-9Z, 11E, 15Z-octadecatrienoic acid (13-HPOTRE(alpha)). The oxidized alpha-linolenic acid- and linoleate-protein adducts were recognized by the antibody. Oxidized phospholipid-protein adducts were scarcely recognized by the antibody. However, when ester bonds of phospholipids containing linoleic acid were hydrolyzed by alkaline treatment, the cross-reactivities appeared. The result suggests that a phospholipid hydroperoxide can react with a protein directly or indirectly, and a carboxyl terminal (COOH) of the lipid in an adduct was needed as an epitope. Oxidized LDL (ox-LDL) was prepared by the incubation of LDL with copper ion or 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), and the formation of lipid hydroperoxide-modified apolipoprotein was confirmed using the antibody. A slight immunoreactivity was observed in ox-LDL without alkaline treatment. When the ox-LDL was treated with alkali to hydrolyze the ester bonds of the lipid, enhanced antigenicity appeared with time-dependency. The results suggest that lipid hydroperoxide-modified apolipoprotein was formed during the oxidation of LDL. 相似文献
84.
85.
Seah Winston Khoon‐Guan Takahashi Yutaka Hasegawa Toshiharu 《Telecommunication Systems》1998,10(3-4):243-268
In this paper, we analyse the message waiting times in a local area network (LAN) that uses the demand‐priority access method.
This is a priority‐based round‐robin arbitration method where the central controller (the repeater) polls its connected ports
to determine which have transmission requests pending and the requests' priority classes. We model it as a 2‐priority M/G/1 queue with multiple server vacations and switchover time between service periods. The service discipline is nonpreemptive
and the length of the switchover time is dependent upon the priority class of the preceding message served as well as that
of the message to be served next. We provide an approximate analysis for the waiting times of both message classes and derive
expressions for the Laplace–Stieltjes transforms (LST) of the stationary distributions and the mean waiting times. We conclude
with numerical and simulation results to show the applicability and accuracy of the analytical model.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
86.
All-optical bistable switching dynamics of 1.55-μm two-segment strained multiquantum-well (MQW) distributed-feedback (DFB) lasers were systematically studied both experimentally and theoretically. Some fundamental optical functionalities, including all-optical set-reset (flip-flop) operations, were demonstrated. The switching responses of these bistable lasers were studied, for the first time, with optical injection from a single-mode DFB laser, indicating that the switching dynamics based on gain quenching and absorption saturation are inherently different. A theoretical model including optical injection was developed to study these all-optical bistable switching characteristics in segmented bistable lasers. It was found that the nonuniform distribution of the photon density in the bistable laser cavity induced by optical injection was essential to perform the time-domain switching operations. Simulations showed a good agreement with experimental observations and indicated design improvements. Although the switching responses in the range of tens of picoseconds can be obtained with these bistable lasers, the maximum repetition frequency of the bistable systems would still be limited to the hundreds of megahertz due to the slow carrier recovery time (5 ns) of the lasers 相似文献
87.
T Aburano R Katada N Shuke W Yamamoto T Kawakami I Makino J Sato Y Ishikawa 《Canadian Metallurgical Quarterly》1997,11(4):335-338
The aim of this study was to estimate the incidence of melanoma in the Paris region in 1994 and analyse the main clinical and histological characteristics of these lesions. It took the form of a prospective inquiry, mailed to public and private pathology laboratories, to count as accurately as possible the number of new cases diagnosed by pathologists in the region during the 1994 calendar year. In all, 1089 newly diagnosed Clark level I to V melanomas (excluding precancerous melanosis of Dubreuilh) were studied. Parameters recorded included age, sex, Clark level and Breslow's thickness. The incidence per 100,000 inhabitants was 9.93 for melanoma and 8.62 for invasive melanoma. The female to male ratio was 1.6. Clark level I or thin (< 0.75 mm) melanomas represented 64.8% of the lesions. At the time of diagnosis, the females were significantly younger than the males (P = 0.004). Breslow's thickness increased with age and was significantly lower in women (P = 0.00005), especially those between 40 and 49 years old. The incidence of melanoma in the Paris region in 1994 was close to that observed during the preceding 5 years in England, Scotland and the French department of Haut-Rhin. It was 2.32 times higher for males and 1.69 times higher for females than the rates estimated for France for the period 1978-1982. 相似文献
88.
Nakamura M. Ueda H. Makino S. Yokotani T. Oshima K. 《Lightwave Technology, Journal of》2004,22(11):2631-2640
The construction of optical access networks is one of key issues to provide new broad-band services and emulation of legacy services. Passive optical network (PON) technologies realize sophisticated and economical optical access networks for these purposes. This paper summarizes requirements and technical and marketing trends for optical access networks. It also presents advantages of networking by PON technologies for optical access networks. Moreover, it clarifies issues to install and operate PON base optical access networks and proposes solutions for these issues. 相似文献
89.
Steady-state fluorescence anisotropy of diphenylhexatriene and n-(9-anthroyloxy)stearic acids (n=2,12) in rat liver microsomes
showed a marked increase in the early stages of enzymatically or non-enzymatically induced lipid peroxidation. The changes
in fluorescence anisotropy occurred in parallel with the formation of thiobarbituric acid-reactive substances (TBA-RS). Parallel
to these changes, the fluorescence emitted from peroxidized microsomes increased markedly in the early stages of lipid peroxidation.
In contrast to the changes in the fluorescence anisotropy and in the formation of TBA-RS, the fluorescence showed a continuing
increase over the three hr period of lipid peroxidation. Glucose-6-phosphatase was inactivated in the early stages of lipid
peroxidation, whereas NADH-cytochrome b5 reductase underwent a slow deactivation over three hr. The apparently slow deactivation of the peripheral protein may be
explained by the formation of fluorescent substances. 相似文献
90.
Nukaiyama Y. Takagi I. Ishihara H. Kudo A. Makino Y. Hosokawa N. 《Power Delivery, IEEE Transactions on》1994,9(4):1885-1891
Gas analysis provides a promising means for a diagnosis of gas-insulated equipment. Although many studies have been concentrated on SF6 gas decomposition, they were mostly related to the faults in GIS systems and not directly applicable to gas-insulated transformers, which have much more complicated material structure. An experimental survey on decomposition by-products at various abnormal conditions was carried out by use of simulation models to develop a diagnostic method for gas-insulated transformers based on gas and ion chromatograph analyses. Major components characteristic in each abnormality, such as SO2 on metal overheat, SO2F 2 on partial discharges, etc. were identified by the experiments 相似文献