We consider an ADSL access network consisting of subscribers, DSLAMs, metro Ethernet switches and a broadband remote access aggregation server (BRAS). We obtain expressions for dimensioning the access network in the upstream direction. Specifically, we show that the bandwidth required at each DSLAM, metro Ethernet switch, and BRAS can be expressed as an exponential function of the subscribers i...

This paper proposes a practical methodology for the problem of designing a metro configuration under two criteria: population coverage and construction cost. It is assumed that a set of corridors defining a rough a priori geometric configuration is provided by the planners. The proposed algorithm consists of fine tuning the location of single alignments within each corridor. This is achieved by...

Complete high-speed quantum key distribution (QKD) systems over fiber networks for campus and metro areas have been developed at NIST. The systems include an 850-nm QKD system for a campus network, a 1310-nm QKD system for metro networks, and a 3-user QKD network and network manager. In this paper we describe the key techniques used to implement these systems, including polarization recovery, n...

A range of proposals are now being considered to reform the health care system, specifically to provide access to health insurance coverage for the uninsured. Proposals from President Obama and members of Congress include a range of public-private approaches, typically called “building blocks” approaches, which build upon our current system of health insurance to provide access to health insura...

Acta Neurologica Taiwanica Vol 20 No 1 March 2011 From the Section of Neurology, Department of Internal Medicine, Tungs’ Taichung Metro Harbor Hospital, Wuci Township; and the Department of Neurology, School of Medicine, Chung Shan Medical University, Taichung, Taiwan. Accepted March 4, 2011. Correspondence to: Dr. Hung-Yi Hsu, Department of Neurology, Tungs’ Taichung Metro Harbor Hospital, No....

Spine Surgery Unit, Departments of Neurosurgery, Sheba Medical Center, Tel Hashomer, Israel Affiliated with Sackler Faculty of Medicine, 1Spine Surgery Unit, Tel‐Aviv Sourasky Medical Center, Weitzman 6, 2Spine Surgery Unit, Assaf Harofeh Medical Center, Sackler Faculty of Medicine, Tel‐Aviv University, 3Neurosurgery, Rambam Medical Center and Faculty of Medicine, Technion‐Israel Istitute of Te...

SimMETRO is a microscopic, dynamic, stochastic simulator of urban rail operations (METRO), specifically designed for service performance analysis, and evaluation of operations and strategies for real time control of subway systems. SimMETRO employs a detailed representation of the network, rolling stock, signal control, demand, schedule and dispatching. In particular, the various sources of sto...

Poverty rates are highest in the most urban and most rural areas of the United States, and are higher in non-metropolitan (nonmetro) than metropolitan (metro) areas, yet rural poverty remains relatively obscured from mainstream political and popular attention. This fact has motivated considerable research by rural social scientists on the relationship between poverty and place generally, and ru...

This white paper describes the performance characteristics, metrics, and testing considerations for EMC VPLEX family of products. Its intent is to refine performance expectations, to review key planning considerations, and to describe testing best practices for VPLEX Local, Metro and Geo. This paper is not suitable for planning for exceptional situations. In configuring for performance, every e...