Material handling device Patent

Device which separates and screens particles of soil samples for vidicon viewing in vacuum and reduced gravity environment

A hybrid ant algorithm for scheduling independent jobs in heterogeneous computing environments

The efficient scheduling of independent computational jobs in a heterogeneous computing (HC) environment is an important problem in domains such as grid computing. Finding optimal schedules for such an environment is (in general) an NP-hard problem, and so heuristic approaches must be used. In this paper we describe an ant colony optimisation (ACO) algorithm that, when combined with local and tabu search, can find shorter schedules on benchmark problems than other techniques found in the literature

A fast, effective local search for scheduling independent jobs in heterogeneous computing environments

The efficient scheduling of independent computational jobs in a heterogeneous computing (HC) environment is an important problem in domains such as grid computing. Finding optimal schedules for such an environment is (in general) an NP-hard problem, and so heuristic approaches must be used. Work with other NP-hard problems has shown that solutions found by heuristic algorithms can often be improved by applying local search procedures to the solution found. This paper describes a simple but effective local search procedure for scheduling independent jobs in HC environments which, when combined with fast construction heuristics, can find shorter schedules on benchmark problems than other solution techniques found in the literature, and in significantly less time

The use of a general linear model to identify epidemiological factors affecting the abundance of chalimus stages of the sea louse (Lepeophtheirus salmonis) on Scottish salmon farms

In this communication chalimus lice numbers in the second, third and fourth quarters of the production cycle are examined in relation to a range of prevailing risk factors using an approach based on that already taken for mobile stages (Revie et al. in press). A total of 54 two-year production cycles from 29 farms on the West Coast of Scotland were analysed. Chalimus levels in the second six-month period of the first year of the production cycle were principally explained (adjusted R2 = 56% of the variation) by:the number of veterinary medicine treatments administered, the site hydrography and current speed characteristics. Sites with a high chalimus abundance attracted more treatments as did fish located in sites with low current speeds and an oscillatory hydrography. In contrast, chalimus levels in the third six-month period of the production cycle were principally explained (adjusted R2 = 65% of the variation) by: the abundance of mobile and chalimus stages in the preceding six-month period and treatment. It would appear that there are both management and environmental factors which affect the number of chalimus sea lice on fish in Scottish salmon farms and these have an impact on overall sea lice abundance

Rare k-decays

This article reviews the current situation in the field of rare K decays: the relevant phenomenology, the present experimental situation, and prospects for the near future. Study of rare K decays can make a significant contribution in a number of different frontier areas of research in high-energy physics. In the area of CP violation, study of such rare decays as K(L)0 --> pi0e+e-, K(L)0 --> pi0mu+mu-, K(L)0 --> pi0nunuBAR, and muon polarization in K(L)0 --> mu+mu- can provide important complementary information to what has been learned from the decay K(L)0 --> pipi. Even though experiments with sufficient accuracy to make a meaningful study of CP violation are still a few years away, significant progress has been made in this general area during the last decade. A second major area of interest in the field of rare K decays is the search for processes forbidden in the Standard Model, e.g., K(L)0 --> mue and K+ --> pi+mu+e-. Various extensions of the Standard Model predict that these processes will occur with branching fractions in the range of 10(-10) to 10(-15). Experiments of the last decade have pushed the limits into the 10(-10) to 10(-11) range, and further improvements in sensitivity of one to two orders of magnitude can be expected in the next few years. K decays allow one also to study higher-order weak-interaction processes such as K(L)0 --> mu+mu-, K(L)0 --> e+e-, K+ --> pi+nunuBAR, which are forbidden to first order in the Standard Model. Because of strong suppression, these decay modes offer potential windows on new physics; in addition, they may offer the most reliable measurement of V(td), one of the elements of the weak mixing matrix in the quark sector. The studies of the mu+mu- channel have achieved data samples of close to 1000 events; the other two modes should be observed for the first time in the next few years. Finally, as a byproduct of these studies, one has been able to look simultaneously for new light particles into which the K meson could decay. Limits obtained for various hypothetical particles are summarized.Physic

Some Empirical Criteria for Attributing Creativity to a Computer Program

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