72,117 research outputs found
Simulation of the Effect of Data Exchange Mode Analysis on Network Throughput
Emergence of large scale specialized networks with a large number of computers
marked a new stage in network infrastructure development. In connection with the wide
variety of modern network equipment used for construction of large-scale networks and
increasing complexity of such networks and applications, a developer or system
administrator can no longer depend mainly on intuitive decisions. Optimum network configuration for realization of concrete tasks and effective deployment of applications in modern terms is not possible without conducting a proper research with the use of specialized simulation tools. Increase in bandwidth is followed by a commensurate increase
in the amount of traffic sent over the Internet. Optimizing the use and allocation of bandwidth continues to be an ongoing problem. We present a simulation model to resolve
the technological challenges of increasing the efficiency of data exchange in computer networks
Entropy and Area in Loop Quantum Gravity
Black hole thermodynamics suggests that the maximum entropy that can be
contained in a region of space is proportional to the area enclosing it rather
than its volume. I argue that this follows naturally from loop quantum gravity
and a result of Kolmogorov and Bardzin' on the the realizability of networks in
three dimensions. This represents an alternative to other approaches in which
some sort of correlation between field configurations helps limit the degrees
of freedom within a region. It also provides an approach to thinking about
black hole entropy in terms of states inside rather than on its surface.
Intuitively, a spin network complicated enough to imbue a region with volume
only lets that volume grow as quickly as the area bounding it.Comment: 7 pages, this essay received an Honourable Mention in the Gravity
Research Foundation Essay Competition 2005; reformatted for IJMP (accepted
for publication) with minor typographical corrections and some extended
discussio
The 2'-5' RNA Ligase of Escherichia coli: Purification, Cloning, and Genomic Disruption
An RNA ligase previously detected in extracts of Escherichia coli is capable of joining Saccharomyces cerevisiae tRNA splicing intermediates in the absence of ATP to form a 2-5 phosphodiester linkage (Greer, C., Javor, B., and Abelson, J. (1983) Cell 33, 899-906). This enzyme specifically ligates tRNA half-molecules containing nucleoside base modifications and shows a preference among different tRNA species. In order to investigate the function of this enzyme in RNA metabolism, the ligase was purified to homogeneity from E. coli lysate utilizing chromatographic techniques and separation of proteins by SDS-polyacrylamide gel electrophoresis. A single polypeptide of approximately 20 kilodaltons exhibited RNA ligase activity. The amino terminus of this protein was sequenced, and the open reading frame (ORF) encoding it was identified by a data base search. This ORF, which encodes a novel protein with a predicted molecular mass of 19.9 kDa, was amplified from E. coli genomic DNA and cloned. ORFs coding for highly similar proteins were detected in Methanococcus jannaschii and Bacillus stearothermophilus. The chromosomal gene encoding RNA ligase in E. coli was disrupted, abolishing ligase activity in cell lysates. Cells lacking ligase activity grew normally under laboratory conditions. However, moderate overexpression of the ligase protein led to slower growth rates and a temperature-sensitive phenotype in both wild-type and RNA ligase knockout strains. The RNA ligase reaction was studied in vitro using purified enzyme and was found to be reversible, indicating that this enzyme may perform cleavage or ligation in vivo
Neutron Stars
Several authors have suggested that the recently discovered extraterrestrial sources of x rays may be hot neutron stars. The plausibility of this suggestion, and in fact the likelihood
that astronomers will ever be able to observe neutron stars by their x-ray emission, depend critically upon the cooling times of the hot stars
Super-Statutes
Not all statutes are created equal. Appropriations laws perform important public functions, but they are usually short-sighted and have little effect on the law beyond the years for which they apportion public monies. Most substantive statutes adopted by Congress and state legislatures reveal little more ambition: they cover narrow subject areas or represent legislative compromises that are short-term fixes to bigger problems and cannot easily be defended as the best policy result that can be achieved. Some statutes reveal ambition but do not penetrate deeply into American norms or institutional practice. Even fewer statutes successfully penetrate public normative and institutional culture in a deep way. These last are what we call super-statutes
TCP/IP Protocol-Based Model for Increasing the Efficiency of Data Transfer in Computer Networks
Developed Algorithm for Increasing the Efficiency of Data Exchange in a Computer Network
This paper presents specialized means to analyze, model and
research of data exchange in large-scale corporate computer
network. Due to extreme complexity of corporate intranet
networks and the internet has resulted in the apparent difficulties in the development of an analytical model. Thus, under these circumstances, simulation models became viable alternative to comprehend the behavior of these complex networks during data exchange. This research work examined the mode of data exchange since its perfection allows in many cases to obtain a considerable improvement of the network and also the network application performance without substantial additional expenditure.
Hence, the need for this developed algorithm for increasing the efficiency of data exchange in a computer network and the appropriate topology that suite this case. Test results from the algorithm showed an average of 10 to 15% increase and occasionally 60% and above increase in data exchange efficiency without additional expenses
- …