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Mohamed T. Refaei, Nader Moayeri, Michael R. Souryal
A common strategy for responding to indoor emergency scenarios is to rapidly deploy a group of first responders inside the incident area and an incident command center outside of the incident area. First responders are equipped with radios that allow them
Market-based compute grids encompass service providers offering limited resources to potential users with varying demands and willingness to pay. Providers face difficult decisions about which jobs to admit and when to schedule admitted jobs. For this
In this paper, we propose a new spatial interpolation algorithm for Intra-Frame error concealment. The method aims at interpolating areas in the image, which have been affected by packet loss. We have proposed an edge detection technique to aid the
Temporal-Angular channel sounding measurements of an indoor millimeter wave channel (60 GHz) is analyzed to determine whether ray arrivals at the receiver form clusters in the two-dimensional time-angle space. The channel behavior for directional antennas
Effective and timely link-layer trigger mechanisms can significantly influence the handover performance. The handover process will not perform the correct decision and execution unless adequate and timely link-layer trigger information is delivered. In
Using cooperative transmission, two or more single-antenna users can share their antennas to achieve spatial diversity in a slow fading channel. One relaying protocol that achieves diversity, amplify-and-forward (AF), is striking in its simplicity, but
Rainer Stiefelhagen, Keni Bernardin, R Bowers, Richard T. Rose, Martial Michel, John S. Garofolo
This paper is a summary of the 2007 CLEAR Evaluation on the Classification of Events, Activities, and Relationships which took place in early 2007 and culminated with a two-day workshop held in May 2007. CLEAR is an international effort to evaluate systems
Traditional Cranfield test collections represent an abstraction of a retrieval task that Sparck Jones calls the core competency of retrieval: a task that is necessary, but not sufficient, for user retrieval tasks. The abstraction facilitates research by
The Domain Name System (DNS) is the global lookup service for network resources. To protect DNS information, the DNS Security Extensions (DNSSEC) has been developed and deployed on branches of the DNS to provide authentication and integrity protection
Patrick J. Grother, Wayne J. Salamon, Michael D. Indovina, Craig I. Watson
The MINEX II trial was conducted to evaluate the accuracy and speed of Match-on-Card verification algorithms. These run on ISO/IEC 7816 smart cards. They compare conformant reference and verification instances of the ISO/IEC 19794-2 COMPACT CARD
Alan Mink, Lijun Ma, Anastase Nakassis, Haolang Xu, Oliver T. Slattery, Barry J. Hershman, Xiao Tang
We have begun to expand the NIST quantum key distribution (QKD) system into a quantum network to support secure cryptography. We are starting with a simple three-node network, one Alice switched between Bob1 and Bob2. To support such a quantum network, we
Michael R. Souryal, E G. Larsson, B M. Peric, B R. Vojcic
This paper derives new soft decision metrics for coded orthogonal signaling in impulsive noise, more specifically symmetric alpha-stable noise. For the case of a known channel amplitude and known noise dispersion, exact metrics are derived both for Cauchy
This paper is mainly concerned with multi-channel transmission of real-time information such as video over multi-hop ad-hoc links. We propose two multi-channel routing protocols. The first is based on single-path routing and aims at suppressing the intra
Lijun Ma, Alan Mink, Hai Xu, Oliver T. Slattery, Xiao Tang
We demonstrate a three-node QKD network that allows multiple users to share secure keys. This QKD network operates on the 850 nm and 1550 nm wavelengths at 1.25 Gbps clock rate. The communication route is controlled by a MEMS optical switch. In this paper
Nader Moayeri, Camillo A. Gentile, Kamran Sayrafian, Michael R. Souryal
Every year a number of first responders lose their lives while battling fires or rescuing civilians during such emergencies. Indoor localization or location tracking roughly provides the same capability inside buildings that GPS does outdoors. It allows a
While the frequency-dependence of the wireless channel may be negligible for narrow to wideband signals, it has been shown that modeling this dependence for bandwidths in excess of 2 GHz improves channel reconstruction up to 40%. Yet to our knowledge, only
Vincent Gauthier, Richard A. Rouil, Nada T. Golmie
In an IEEE 802.11 network, a single user can reduce the performance of all other users attached to the same access point. To overcome this problem, we propose to take advantage of the increasing number of devices supporting multiple network interfaces. We
In this paper, a Dynamic Source Routing (DSR)-based directional routing protocol is invoked for wireless ad hoc networks using directional antennas. This is designed to balance the trade-off between co-channel interferences from nodes hops away, and the
Effective and timely link layer trigger mechanisms can significantly influence the handover performance. In this paper, a predictive link trigger mechanism for seamless horizontal and vertical handovers in heterogeneous wireless networks is proposed
This brochure describes the programs of the Information Technology Laboratory (ITL). Following a letter from the ITL Director, ITL's nine programs are described, and ITL's mission, core competencies, resources, products, and customers are given, followed
Flow-level performance of fair bandwidth sharing protocols under random flow arrivals/departures is not sufficiently understood due to intractability of the corresponding Markov model for realistic-size networks. Tractability of the Markov model in fluid
A flow-level Markov model for fair bandwidth sharing with packet retransmissions under random flow arrivals/departures is proposed and discussed. Fluctuations in the numbers of flows in progress cause the network instability even under light load. The
Behnam Neekzad, Kamran Sayrafian, Julio Perez, John Baras
Temporal-Angular channel sounding measurements of an indoor millimeter wave channel (60 GHz) is analyzed to determine the location of two dimensional clusters of arrivals at the receiver. The measurement scenarios are also emulated by a ray tracing tool