Abstract
We present a new formulation for the direct laser acceleration of electrons in vacuum based on the Hamiltonian theory, Two different regimes for the snow-plowed, accelerated electrons are identified and characterized, the first pertaining to high-intensity and the second to low-intensity pulses, both leading to efficient electron acceleration. Particle energy yields are shown to be independent of the exact shape of the laser pulse and energy gains are estimated.

Abstract
We study the origin of antisymmetric perturbation of the fiber in arc-induced long-period gratings that couple the core mode into the antisymmetric cladding modes. We demonstrate that this perturbation is caused by the temperature gradient in the fiber, which is induced, in turn, by the temperature gradient in the arc discharge. The reproducibility of the process of the grating inscription is higher when the fiber is placed in a region with larger temperature gradient. (c) 2007 Optical Society of America.

Abstract
This paper is on the problem of short-term hydro scheduling, particularly concerning head-dependent reservoirs under competitive environment. We propose a method, based on nonlinear programming, for optimizing power generation efficiency. The proposed method considers not only that the hydroelectric power generation is a function of the water discharge and of the head, but also that the maximum power generation is head-dependent. Numerical results based on a realistic cascaded hydro system illustrate the proficiency of the proposed method.

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Abstract
The mapping of applications to FPGAs involves the exploration of a potentially large space of possible design choices with long and error-prone design cycles. Automated compiler analysis and transformation techniques aim at improving the design productivity of this mapping process by reducing the design cycles while still leading to good desigs. Scalar replacement, also known as, register promotion, leads to designs that reduce the number of external memory accesses, and thus reduce the execution time, by the use of storage resource. In this paper we present the combination of loop transformation techniques, namely loop unrolling, loop splitting and loop interchange with scalar replacement. to enable partial data reuse on computations expressed by tightly nested loops pervasive in image processing algorithms. We describe an accurate performance modeling in the presence of partial data reuse. Our experimental results reveal that our model accurately captures the non-trivial execution effects of pipelined implementations in the presence of partial data reuse due to the need to fill-up data buffers. The model thus allows a compiler to explore a large design space with high accuracy, ultimately allowing compiler tools to find better design than using brute-force approaches.