158,698 research outputs found
Educating California: Choices for the Future
Outlines the need to improve the K-12 and higher education systems to close the projected skills gap in the labor force. Recommends reducing high school dropout rates and increasing community college transfer rates and graduation rates at state colleges
Sergei Rachmaninoff's Étude Tableau op. 39, no. 7; arranged for full band
Thesis (M.M.)--Boston University, 196
Defunding Higher Education: What Are the Effects on College Enrollment?
Examines the effects of the state's higher education spending cuts on enrollment rates of eligible, highly prepared students at the University of California, California State University, and California Community Colleges systems. Outlines implications
Closing the Gap: Meeting California's Need for College Graduates
Estimates the state's shortage in highly educated workers in 2025 and outlines ways to raise college attendance rates, transfer rates from community colleges, and graduation rates from four-year institutions to help close the gap. Discusses policy issues
The braiding for representations of q-deformed affine
We compute the braiding for the `principal gradation' of for from first principles, starting from the idea of a rigid
braided tensor category. It is not necessary to assume either the crossing or
the unitarity condition from S-matrix theory. We demonstrate the uniqueness of
the normalisation of the braiding under certain analyticity assumptions, and
show that its convergence is critically dependent on the number-theoretic
properties of the number in the deformation parameter . We also examine the convergence using probability, assuming a uniform
distribution for on the unit circle.Comment: LaTeX, 10 pages with 2 figs, uses epsfi
Selfish Knapsack
We consider a selfish variant of the knapsack problem. In our version, the
items are owned by agents, and each agent can misrepresent the set of items she
owns---either by avoiding reporting some of them (understating), or by
reporting additional ones that do not exist (overstating). Each agent's
objective is to maximize, within the items chosen for inclusion in the
knapsack, the total valuation of her own chosen items. The knapsack problem, in
this context, seeks to minimize the worst-case approximation ratio for social
welfare at equilibrium. We show that a randomized greedy mechanism has
attractive strategic properties: in general, it has a correlated price of
anarchy of (subject to a mild assumption). For overstating-only agents, it
becomes strategyproof; we also provide a matching lower bound of on the
(worst-case) approximation ratio attainable by randomized strategyproof
mechanisms, and show that no deterministic strategyproof mechanism can provide
any constant approximation ratio. We also deal with more specialized
environments. For the case of understating-only agents, we provide a
randomized strategyproof -approximate
mechanism, and a lower bound of . When all
agents but one are honest, we provide a deterministic strategyproof
-approximate mechanism with a matching
lower bound. Finally, we consider a model where agents can misreport their
items' properties rather than existence. Specifically, each agent owns a single
item, whose value-to-size ratio is publicly known, but whose actual value and
size are not. We show that an adaptation of the greedy mechanism is
strategyproof and -approximate, and provide a matching lower bound; we also
show that no deterministic strategyproof mechanism can provide a constant
approximation ratio
Collapse and revival dynamics of superfluids of ultracold atoms in optical lattices
Recent experiments have shown a remarkable number of collapse-and-revival
oscillations of the matter-wave coherence of ultracold atoms in optical
lattices [Will et al., Nature 465, 197 (2010)]. Using a mean-field
approximation to the Bose-Hubbard model, we show that the visibility of
collapse-and-revival interference patterns reveal number squeezing of the
initial superfluid state. To describe the dynamics, we use an effective
Hamiltonian that incorporates the intrinsic two-body and induced three-body
interactions, and we analyze in detail the resulting complex pattern of
collapse-and-revival frequencies generated by virtual transitions to higher
bands, as a function of lattice parameters and mean-atom number. Our work shows
that a combined analysis of both the multiband, non-stationary dynamics in the
final deep lattice, and the number-squeezing of the initial superfluid state,
explains important characteristics of optical lattice collapse-and-revival
physics. Finally, by treating the two- and three-body interaction strengths,
and the coefficients describing the initial superposition of number states, as
free parameters in a fit to the experimental data it should be possible to go
beyond some of the limitations of our model and obtain insight into the
breakdown of the mean-field theory for the initial state or the role of
nonperturbative effects in the final state dynamics.Comment: 5 pages, 5 figures. This is the updated version published June 201
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