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1.
The telecommunications information networking architecture (TINA), which builds on the current advances in broadband communication and distributed computing technologies, specifying a software-based architecture for future information networks that are required to transport multimedia information and manage multimedia communication, is described. An important aspect of the architecture is that service segment functions are separated from delivery segment functions. Another key aspect is the elimination of the rigid division between network applications and operations applications that exists in current-day networks. In the TINA architecture, both kinds of applications execute on a common distributed processing platform that hides from applications the effects and complexities introduced by distribution. The architecture supports application interoperability enabling flexible construction of services, composed of service components distributed across network domains, allowing network operators and service providers to cooperatively meet the needs of the user 相似文献
2.
Bound-state beta decay of highly ionized atoms 总被引:1,自引:0,他引:1
3.
4.
5.
Masturzo S.A. Yarrison-Rice J.M. Jackson H.E. Boyd J.T. 《Nanotechnology, IEEE Transactions on》2007,6(6):622-626
Grating couplers with nanoscale periodicity have been fabricated on silicon-on-insulator (SOI) substrates by electron beam lithography and reactive ion etching. A versatile experimental apparatus has been implemented to measure the efficiency of these gratings in coupling free-space radiation into planar waveguides. This coupling efficiency has been measured as a function of grating depth and the angle and wavelength of incident radiation. Coupling efficiencies of at least 5% and as high as 20% are demonstrated for wavelengths in the vicinity of 1550 nm and incident angles around 45deg. 相似文献
6.
S. Boyd Eaton 《Lipids》1992,27(10):814-820
The genetically ordered physiology of contemporary humans was selected over eons of evolutionary experience for a nutritional
pattern affording much less fat, particularly less saturated fat. Current dietary recommendations do not accord exactly with
those generated by an understanding of prior hominoid/hominid evolution. Similarly, widely advocated standards for serum cholesterol
values fail to match those observed in recently studied hunter-gatherers, whose experience represents the closest living approximation
of “natural” human lipid metabolism. The evolutionary paradigm suggests that fats should comprise 20–25% of total energy intake,
that the ratio of polyunsaturated to saturated fat should exceed 1.0, and that total serum cholesterol levels should be below
150 mg/dL (∼4 mM/L).
Based on a paper presented at the Symposium on Lipids in Cancer held at the AOCS Annual Meeting, Baltimore, MD, April 1990. 相似文献
7.
D. B. Zeik J. R. Dugan D. W. Schroeder J. W. Baur S. J. Clarson G. N. De Brabander J. T. Boyd 《应用聚合物科学杂志》1995,56(9):1039-1044
Plasma-polymerized hexamethyldisiloxane (HMDS) films have been prepared as both planar and channel wave guides. The optical attenuation results measured in both the planar and channel HMDS wave guides were found to be similar, thus demonstrating that the inherent solvent resistance and chemical inertness of the plasma polymerized films allows the use of common photoresist techniques, including application of the photoresist, photomasking, and subsequent etching. This may be contrasted with wave guides made from conventional polymers, where careful consideration must be given to photoresist/polymer compatibility, because the photoresist solvents may adversely affect the underlying polymer and lead to degradation of the material during processing. © 1995 John Wiley & Sons, Inc. 相似文献
8.
Microstructural changes in concretes with sulfate exposure 总被引:1,自引:0,他引:1
In prior papers the responses of concretes to 50,000 ppm MgSO4 exposure depending on cement type, w/cm and the presence of slag were described. The present paper completes this analysis by examining the effects of immersion of concretes produced using slag blended cements, in solutions containing 50,000 ppm of sodium sulfate. The spatial evolution of microstructure associated with carbonation and sulfate attack show differences which can be related to the nature of the cation associated with the sulfate, the cement type, and the w/cm ratio. 相似文献
9.
S Kozlowski M Corr M Shirai LF Boyd CD Pendleton JA Berzofsky DH Margulies 《Canadian Metallurgical Quarterly》1993,151(8):4033-4044
T cell stimulation by certain class I-restricted antigenic peptides, such as the HIV 1 gp160-derived peptide, P18, requires peptide processing by angiotensin-1 converting enzyme (ACE) in FCS. We observed that longer versions of P18 and the murine cytomegalovirus pp89-derived core peptide, pMCMV, which could stimulate T cell hybridomas in FCS, were not as sensitive to the ACE inhibitor captopril as P18. Using cell-free soluble murine class I MHC molecules and protease inhibitors, we found that there are pathways of differing efficiency that use enzymes other than ACE for the proteolytic processing of peptides in serum. The kinetics of the generation of T cell stimulatory activity among P18 variant peptides in serum differed with peptide length, and with the nature of amino and COOH-terminal extensions. Such processing occurs in human plasma as well as in FCS. The understanding of this processing, its kinetics, and its inhibitors can lead to better design of peptide-based therapies, including vaccines. 相似文献
10.
M Albert C Athanassopoulos LB Auerbach D Bauer R Bolton B Boyd RL Burman I Cohen DO Caldwell BD Dieterle JB Donahue AM Eisner A Fazely FJ Federspiel GT Garvey RM Gunasingha V Highland J Hill R Imlay K Johnston WC Louis A Lu AK Mann J Margulies K McIlhany W Metcalf RA Reeder V Sandberg M Schillaci D Smith I Stancu W Strossman MK Sullivan GJ VanDalen W Vernon YX Wang DH White D Whitehouse D Works Y Xiao S Yellin 《Canadian Metallurgical Quarterly》1995,51(3):R1065-R1069