3 resultados para Supervisory Control and Data Acquisition (SCADA)

em Greenwich Academic Literature Archive - UK


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Review of: Rights of the Accused, Crime Control and Protection of Victims. Edited by Eliahu Harnon & Alex Stein. A special volume of the Israel Law Review, Vol. 31, Nos. 1-3, Winter-Summer 1997. Published by the Faculty of Law, Hebrew University, Jerusalem.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Analysis of the generic attacks and countermeasures for block cipher based message authentication code algorithms (MAC) in sensor applications is undertaken; the conclusions are used in the design of two new MAC constructs Quicker Block Chaining MAC1 (QBC-MAC1) and Quicker Block Chaining MAC2 (QBC-MAC2). Using software simulation we show that our new constructs point to improvements in usage of CPU instruction clock cycle and energy requirement when benchmarked against the de facto Cipher Block Chaining MAC (CBC-MAC) based construct used in the TinySec security protocol for wireless sensor networks.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We consider the optimum design of pilot-symbol-assisted modulation (PSAM) schemes with feedback. The received signal is periodically fed back to the transmitter through a noiseless delayed link and the time-varying channel is modeled as a Gauss-Markov process. We optimize a lower bound on the channel capacity which incorporates the PSAM parameters and Kalman-based channel estimation and prediction. The parameters available for the capacity optimization are the data power adaptation strategy, pilot spacing and pilot power ratio, subject to an average power constraint. Compared to the optimized open-loop PSAM (i.e., the case where no feedback is provided from the receiver), our results show that even in the presence of feedback delay, the optimized power adaptation provides higher information rates at low signal-to-noise ratios (SNR) in medium-rate fading channels. However, in fast fading channels, even the presence of modest feedback delay dissipates the advantages of power adaptation.