Transport-driven toroidal rotation in the tokamak edge

The interaction of passing-ion drift orbits with spatially-inhomogeneous but purely diffusive radial transport is demonstrated to cause spontaneous toroidal spin-up to experimentally-relevant values in the tokamak edge. Physically, major-radial orbit shifts cause orbit-averaged diffusivities to depend on parallel velocity, including its sign, leading to residual stress. The resulting intrinsic rotation scales with ion temperature over poloidal magnetic field strength, resembling typical experimental scalings. Additionally, an inboard (outboard) X-point is expected to enhance co- (counter-) current rotation

A heat quench algorithm for the minimization of multiple-valued programmable logic arrays

This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted.Computer and Electrical Engineering Journal, Vol. 22, No. 2, 1996, pp. 103-107, 1996imulated annealing has been used extensively to solve combinatorial problems. Although it does not guarantee optimum results, results are often optimum or near optimum. The primary disadvantage is slow speed. It has been suggested [1] that quenching (rapid cooling) yields results that are far from optimum. We challenge this perception by showing a context in which quenching yields good solutions with good computation speeds. In this paper, we present an algorithm in which quenching is combined with rapid heating. We have successfully applied this algorithm to the multiple-valued logic minimization problem. Our results suggest that this algorithm holds promise for problems where moves exist that leave the cost of the current solution unchanged. Key words: Multiple-valued logic, logic minimization, simulated annealing, heat quench, heuristic

Multiple-valued operations with universal literals

This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted.Proceedings of the 24th International Symposium on Multiple-Valued Logic, May 1994, pp. 73-79, 1993We propose the use of universal literals as a means of reducing the cost of multiple-valued circuits. A universal literal is any function on one variable. The target architecture is a sum-of-products structure, where sum is the truncated sum and product terms consist of the minimum of universal literals. A significant cost reduction is demonstrated over the conventional window literal. The proposed synthesis method starts with a sum- of products expression. Simplification occurs as pairs of product terms are merged and reshaped. We show under what conditions such operations can be applied

A minimization algorithm for non-concurrent PLA's

This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted.International Journal of Electronics, Vol. 73, No. 6, Dec. 1992, pp. 1113-1119In the design of certain self-checking programmable logic arrays (PLAs), at most one line is activated in the AND plane, such as PLAs are termed non-concurrent. A heuristic algorithm for the minimization of non-concurrent PLAs is presented. It operates on two adjacent cubes, replacing them by one, two, and sometimes more than two cubes. The algorithm produces the best solutions known so far

On the number of generators for transeunt triangles

This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted.Discrete Applied Mathematics, 108, 2001, pp. 309-316A transeunt triangle for size n consists of (n+1)x(n+1)x(n+1) 0's and 1's whose values are determined by the sum modulo 2 of two other local values. For a given n, two transeunt triangles of size n can be combined using the element-by-element modulo 2 sum to generate a third transeunt triangle. We show that, for large n ..

Multiple-valued Logic Operations with Universal Literals

We propose the use of universal literals as a means of reducing the cost of multiple-valued circuits. A universal literal is any function on one variable. The target architecture is a sum-of-products structure, where sum is the truncated sum and product terms consist of the minimum of universal literals. A significant cost reduction is demonstrated over the conventional window literal. The proposed synthesis method starts with a sum-of-products expression. Simplification occurs as pairs of producttermsaremergedandreshaped. Weshowunder what conditions such operations can be applied.Research supported by the Natural Sciences and Engineering Research Council of Canada and by the Naval Research Laboratory, Washington, DC through direct funds at the Naval Postgraduate School, Monterey, CAResearch supported by the Natural Sciences and Engineering Research Council of Canada and by the Naval Research Laboratory, Washington, DC through direct funds at the Naval Postgraduate School, Monterey, C