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991.
A virtual machine monitor (VMM) allows a single computer to run two or more operating systems at the same time. VMMs are relatively simple and are typically built to high assurance standards, which means that the quality of isolation provided by a virtual machine monitor is usually greater than that which can be achieved with a general-purpose operating system. This paper discusses how the flexibility afforded by multiple OS environments and the robust isolation provided by a virtual machine monitor can be used to improve client PC security. A prototype system is also described.This paper is neither a product announcement nor an official Microsoft position paper, but rather it is a discussion of interesting configuration options that can be constructed using existing Microsoft and third-party products: in this case two or more operating systems running in conjunction with a virtual machine monitor.  相似文献   
992.
Ribbon cables have been widely used as subsystem interconnections in a large number of digital systems, because they can convey numerous bits of a digital signal simultaneously. In this article, finite difference and finite difference time domain (FDTD) methods are used to analyze and optimize the electrostatic analysis design of ribbon cables, and measurements are used to verify the numerical results. © 2002 Wiley Periodicals, Inc. Int J RF and Microwave CAE 12: 148–158, 2002.  相似文献   
993.
The potential of Electronic Data Interchange (EDI) has not yet been fully realized despite the existence of appropriate standards and technologies. Service providers in this area play an important role as providers of the infrastructure, providers of conversion programs, or consultants. This paper examines the critical success factors of EDI service providers as perceived by them and their customers. It finds that the views of these groups are partly divergent, especially with respect to the need for knowledge of business processes. The findings can help providers to improve their services for their own benefit and the benefit of their users.  相似文献   
994.
Failures frequently occur in developing countries' electrical energy distribution networks. This paper proposes an approach to network reliability through modelling the interruptions on medium voltage lines. This modelling is based on a representative feeder sampling of a source station in an urban area. In order to determine the probability law governing these interruptions, statistical techniques were used: density estimation using the kernel method and approximation by the least squares. The results we obtained show that, from the quality of the equipment and their maintenance, interruptions for a given network follow a truncated and shifted gamma distribution or a truncated normal law. For the managers of such systems, these results would allow, amongst other things, reduction in the probability of failure, thus improving operational safety on electricity distribution with medium voltage lines.  相似文献   
995.
We consider the modified conjugate gradient procedure for solving A = in which the approximation space is based upon the Krylov space associated with A 1/p and , for any integer p. For the square-root MCG (p=2) we establish a sharpened bound for the error at each iteration via Chebyshev polynomials in . We discuss the implications of the quickly accumulating effect of an error in in the initial stage, and find an error bound even in the presence of such accumulating errors. Although this accumulation of errors may limit the usefulness of this method when is unknown, it may still be successfully applied to a variety of small, almost-SPD problems, and can be used to jump-start the conjugate gradient method. Finally, we verify these theoretical results with numerical tests.  相似文献   
996.
Call for Papers     

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997.
998.
An innovative TPO, based upon a complex fluid, is described, which shows an unusual balance of physical properties. The effects of complex fluid composition are addressed in a statistically designed experiment. Physical performance, rheological effects, thermal analysis, and morphological characterization are reported. J. VINYL ADDIT. TECHNOL., 12:183–191, 2006. © 2006 Society of Plastics Engineers  相似文献   
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