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ADVANCES
IN CIRCUITS AND SYSTEMS 2, November 2004
A quarterly news service of the IEEE Circuits
and Systems Society
Editor: Martin Hasler VP Technical Activities CONTENTS
1. Nonlinear Circuit Foundations for Nanodevices
2. Structure of Internet topology
3. JPEG 2000 Part
11: Standard for Wireless Image Communication
4. Transmission Capacity
of Wireless Adhoc Networks
5. External and Internal
Dynamics of Complex Systems
1. Nonlinear
Circuit Foundations for Nanodevices
Description by Bing Sheu, Peter Chung-Yu Wu, and Simon M. Sze:
A nanodevice cannot perform
information processing unless it is locally active—a
deep circuit-theoretic property referring to the
circuit model of the device. High-frequency nanodevices
are modelled by a family of nonlinear
circuit elements capable of emulating such exotic quantum-mechanical
effects as Coulomb blockade, Kondo resonance, quasiparticle interactions, Aharonov–Bohm nonlocality, etc. These model
building blocks are defined axiomatically and represented
periodically via a four-element torus.
Reference: L.
O. Chua, “Nonlinear Circuit Foundations for Nanodevices,
Part I: The Four-Element Torus,”
Proceedings of The IEEE, Vol. 91,
No. 11, pp. 1830-1859, November, 2003.
Communicated
by the Technical Committee
on Nanoelectronics and Giga-scale Systems
2.
Structure of Internet Topology
Description by Krishnaiya Thulasiraman: Performance evaluation of protocols/algorithms of interest
in communication network analysis and design is usually carried
out using extensive simulation on randomly generated networks.
Several toplogy generators are available in the literature. Recently
it was observed that power laws capture concisely the distributions of graph properties.
The following references provide a good introduction to this
area and current research trends.
References:
1.
G.
Siganos, M. Faloutsos
and P.Faloutsos and C. Faloutsos, “
Power Laws and the AS Level Internet Topology”, IEEE/ACM
Transactions on Networking, vol.11, no.4, August 2003, pp. 514-524.
2.
Shard Jaiswal, Arnold L. Rosenberg and Don Towsley,
“Comparing the structure of power law graphs and the
internet AS Graph” , to appear in ICNP 2004, Berlin, Germany October 5 – 8, 2004.
Communicated by the
Technical Committee on Graph Theory and Computing
3. JPEG 2000 Part 11: Standard for Wireless Image Communication
Description by Enrico
Magli: Part 11 of the
JPEG 2000 standard (JPWL) addresses wireless transmission
of images and video sequences. It builds on the high coding
efficiency and error-resilience tools provided by Part 1 (core
coding system) and Part 3 (motion), by providing additional
error protection mechanisms (including header protection)
to cope with harsh channel and network conditions.
Reference: http://www.jpeg.org/jpeg2000/j2kpart11.html
Communicated by the Technical Committee on Multimedia Systems
and Applications
4. Transmission Capacity of Adhoc
Wireless
Networks
Description by Martin Hasler: In mobile wireless
networks without base stations, the mobile transmitters not
only send information to each other, but they also relay messages
for other users. Because of interference between nearby transmitters,
in a network with of fixed area with n users, the useful information
rate for each user decreases roughly as 1/sqrt(n) (cf. Paper
1). Paper (2)
uses a refined model for extended networks, and paper (3)
shows that mobility can actually help for information transmission.
References:
1.
P.Gupta, P.R.Kumar,
“The Capacity of Wireless Networks”, IEEE Transactions
on Information Theory, vol.46, nb.2, March 2000, pp. 388-404.
2.
Liang-Liang Xie,
P.R.Kumar, “A Network Information Theory for Wireless
Communication: Scaling Laws and Optimal Operation”,
IEEE Transactions on Information Theory, vol. 50, nb.5, May
2004, pp. 748-767.
3. M.Grossglauser, D.Tse, “Mobility
Increases the Capacity of Ad Hoc Wireless Networks”,
IEEE/ACM Transactions on Networking, vol.10, nb.4, August
2002, pp. 477-486.
5. External and Internal Dynamics of Complex Systems
Description by Martin Hasler: Simultaneously recorded time series
from large networks are analyzed. A simple algorithm often
allows to separate the contribution of (unknown) external signals
from the contribution of the (unknown) internal network dynamics.
With this method it is shown that the dynamics of Internet
router traffic and communication traffic on a chip are internally
driven, whereas Web and highway traffic are externally driven.
Reference:
M.Argollo de Menezes,
A. Barabasi, “Separating External and Internal Dynamics”,
Physical Review Letters, vol.93, nb.6, August 2004, pp. 068701 1-4.
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