70,931 research outputs found
The Art Institute of Chicago and the Decision to Start Building
This case was prepared for a class discussion rather than to demonstrate either effective or ineffective handling of an administrative situation, and is based on interviews with 12 current and former members of the staff and board of the Art Institute of Chicago, as well as financial documents and the public record. The authors would like to thank all of the people who graciously agreed to be interviewed
John Templeton Foundation: Capabilities Report
This annual report, celebrating the 25th anniversary of the foundation, includes letters from its leaders, a history of the foundation, details of current grantmaking and other activities, financial statements, and lists of trustees
PICES Press, Vol. 15, No. 2, July 2007
Contents [Individual sections are downloadable from the official URL link listed below]: PICES Science in 2007 (pdf, 0.1 Mb)
2007 Wooster Award (pdf, 0.1 Mb)
FUTURE - A milestone reached but our task is not done (pdf, < 0.1 Mb)
International symposium on "Reproductive and Recruitment Processes of Exploited Marine Fish Stocks" (pdf, 0.1 Mb)
Recent results of the micronekton sampling inter-calibration experiment (pdf, 0.1 Mb)
2007 PICES workshop on "Measuring and monitoring primary productivity in the North Pacific" (pdf, 0.1 Mb)
2007 Harmful Algal Bloom Section annual workshop events (pdf, 0.1 Mb)
A global approach for recovery and sustainability of marine resources in Large Marine Ecosystems (pdf, 0.3 Mb)
Highlights of the PICES Sixteenth Annual Meeting (pdf, 0.4 Mb)
Ocean acidification of the North Pacific Ocean (pdf, 0.3 Mb)
Workshop on NE Pacific Coastal Ecosystems (2008 Call for Salmon Survival Forecasts) (pdf, 0.1 Mb)
The state of the western North Pacific in the first half of 2007 (pdf, 0.4 Mb)
PICES Calendar (pdf, 0.4 Mb)
The Bering Sea: Current status and recent events (pdf, 0.3 Mb)
PICES Interns (pdf, 0.3 Mb)
Recent trends in waters of the subarctic NE Pacific (pdf, 0.3 Mb)
Election results at PICES (pdf, 0.2 Mb)
A new PICES award for monitoring and data management activities (pdf, < 0.1 Mb
Slow Adaptive OFDMA Systems Through Chance Constrained Programming
Adaptive OFDMA has recently been recognized as a promising technique for
providing high spectral efficiency in future broadband wireless systems. The
research over the last decade on adaptive OFDMA systems has focused on adapting
the allocation of radio resources, such as subcarriers and power, to the
instantaneous channel conditions of all users. However, such "fast" adaptation
requires high computational complexity and excessive signaling overhead. This
hinders the deployment of adaptive OFDMA systems worldwide. This paper proposes
a slow adaptive OFDMA scheme, in which the subcarrier allocation is updated on
a much slower timescale than that of the fluctuation of instantaneous channel
conditions. Meanwhile, the data rate requirements of individual users are
accommodated on the fast timescale with high probability, thereby meeting the
requirements except occasional outage. Such an objective has a natural chance
constrained programming formulation, which is known to be intractable. To
circumvent this difficulty, we formulate safe tractable constraints for the
problem based on recent advances in chance constrained programming. We then
develop a polynomial-time algorithm for computing an optimal solution to the
reformulated problem. Our results show that the proposed slow adaptation scheme
drastically reduces both computational cost and control signaling overhead when
compared with the conventional fast adaptive OFDMA. Our work can be viewed as
an initial attempt to apply the chance constrained programming methodology to
wireless system designs. Given that most wireless systems can tolerate an
occasional dip in the quality of service, we hope that the proposed methodology
will find further applications in wireless communications
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