A QCD Calculation of the Interaction of Quarkonium with Nuclei

The interaction of quarkonium with nuclei is studied in the $m_Q\rightarrow \infty$ limit of QCD, where the binding energy is found to be exactly computable. The dominant contribution to the interaction is from two-gluon operators. The forward matrix elements of these two-gluon operators can be determined from the QCD scale anomaly, and from deep inelastic scattering. We apply our results to the $\Upsilon$ and $J/\psi$, treating the \qqbar interaction as purely Coulombic. We find the $\Upsilon$ binds in nuclear matter with a binding energy of a few \mev, while for the $J/\psi$ binding is of order 10 \mev. For the $J/\psi$ in particular we expect confinement effects to produce large corrections to this result.Comment: (10 pages

Heat sink effects on weld bead: VPPA process

An investigation into the heat sink effects due to weldment irregularities and fixtures used in the variable polarity plasma arc (VPPA) process was conducted. A basic two-dimensional model was created to represent the net heat sink effect of surplus material using Duhamel's theorem to superpose the effects of an infinite number of line heat sinks of variable strength. Parameters were identified that influence the importance of heat sink effects. A characteristic length, proportional to the thermal diffusivity of the weldment material divided by the weld torch travel rate, correlated with heat sinking observations. Four tests were performed on 2219-T87 aluminum plates to which blocks of excess material were mounted in order to demonstrate heat sink effects. Although the basic model overpredicted these effects, it correctly indicated the trends shown in the experimental study and is judged worth further refinement

How Good a Deal Was the Tobacco Settlement?: Assessing Payments to Massachusetts

We estimate the increment in Massachusetts Medicaid program costs attributable to smoking from December 20, 1991, to 1998. We describe how our methods improve upon earlier estimates of analogous costs at the national level. Current costs to the Massachusetts Medicaid program approximate the payments to Massachusetts under the tobacco settlement of November 1998. Whether these payments are viewed as appropriate compensation for Medicaid costs over time depends upon the rate of increase in future health care costs, the rate of decline in smoking, the proportion of smoking that should be attributed to the actions of the tobacco companies and the liklihood that state would have prevailed at trial. The costs to the Medicaid program are dwarfed by the internal costs to smokers themselves.

Density Functional Theory Study of the Oligomerization of Carboxylic Acids

D.D.T. thanks the U.K.’s Royal Society for the award of a Royal Society Industry Fellowship. This research utilized Queen Mary’s MidPlus computational facilities, supported by QMUL Research-IT and funded by EPSRC grant EP/K000128/1. Via our membership of the U.K.’s HPC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202), this work made use of the facilities of HECToR and ARCHER, the U.K.’s national high-performance computing service, which is funded by the Office of Science and Technology through EPSRC’s High End Computing Programme.publisher pdf not permitted, withdraw

On the number of perfect lattices

We show that the number $p\_d$ of non-similar perfect $d$-dimensional lattices satisfies eventually the inequalities$e^{d^{1-\epsilon}}<p\_d<e^{d^{3+\epsilon}}$ for arbitrary smallstrictly positive $\epsilon$

Description and preliminary studies of a computer drawn instrument landing approach display

A computer drawn instrument landing approach display, which shows a box located on the desired path, aligned with the path, and moving along the path at a selected distance ahead of the aircraft, was examined. Vertical and lateral displacements from the desired path and aircraft altitude information are used as inputs to the computer. A preliminary simulation study with pilot subjects has shown that the pilots find the display very easy to use, and they achieved better performance scores with the box display than with a cross pointer instrument landing display

Information technology and efficiency in trucking

In this paper, we develop an econometric model to estimate the impacts of Electronic Vehicle Management Systems (EVMS) on the load factor (LF) of heavy trucks using data at the operational level. This technology is supposed to improve capacity utilization by reducing coordination costs between demand and supply. The model is estimated on a subsample of the 1999 National Roadside Survey, covering heavy trucks travelling in the province of Quebec. The LF is explained as a function of truck, trip and carrier characteristics. We show that the use of EVMS results in a 16 percentage points increase of LF on backhaul trips. However, we also find that the LF of equipped trucks is reduced by about 7.6 percentage points on fronthaul movements. This last effect could be explained by a rebound effect: higher expected LF on the returns lead carriers to accept shipments with lower fronthaul LF. Overall, we find that this technology has increased the tonne-kilometers transported of equipped trucks by 6.3% and their fuel efficiency by 5%.Information and Communication Technology, Efficiency, Load factor, Trucking, Energy Efficiency