New structural approach for determining load carrying capability of filament wound composite materials

Metal lined boron and graphite composites exhibit high strength and minimum weight, making them superior to aluminum cylindrical shell structures and to steel or aluminum constructed pressure vessels. S glass filament-epoxy resin matrix with aluminum liner is suitable for cryogenic tanks

Imperfection Information, Optimal Monetary Policy and Informational Consistency

This paper examines the implications of imperfect information (II) for optimal monetary policy with a consistent set of informational assumptions for the modeller and the private sector an assumption we term the informational consistency. We use an estimated simple NK model from Levine et al. (2012), where the assumption of symmetric II significantly improves the fit of the model to US data to assess the welfare costs of II under commitment, discretion and simple Taylor-type rules. Our main results are: first, common to all information sets we find significant welfare gains from commitment only with a zero-lower bound constraint on the interest rate. Second, optimized rules take the form of a price level rule, or something very close across all information cases. Third, the combination of limited information and a lack of commitment can be particularly serious for welfare. At the same time we find that II with lags introduces a ‘tying ones hands’ effect on the policymaker that may improve welfare under discretion. Finally, the impulse response functions under our most extreme imperfect information assumption (output and inflation observed with a two-quarter delay) exhibit hump-shaped behaviour and the fiscal multiplier is significantly enhanced in this case

On the Energy and Centrality Dependence of Higher Order Moments of Net-Proton Distributions in Relativistic Heavy Ion Collisions

The higher order moments of the net-baryon distributions in relativistic heavy ion collisions are useful probes for the QCD critical point and fluctuations. Within a simple model we study the colliding energy and centrality dependence of the net-proton distributions in the central rapidity region. The model is based on considering the baryon stopping and pair production effects in the processes. Based on some physical reasoning, the dependence is parameterized. Predictions for the net-proton distributions for Au+Au and Pb+Pb collisions at different centralities at $\sqrt{s_{NN}}$=39 and 2760 GeV, respectively, are presented from the parameterizations for the model parameters. A possible test of our model is proposed from investigating the net proton distributions in the non-central rapidity region for different colliding centralities and energies.Comment: 6 pages in revtex4, 8 eps figures. arXiv admin note: text overlap with arXiv:1107.474

Information, VARs and DSGE Models

How informative is a time series representation of a given vector of observables about the structural shocks and impulse response functions in a DSGE model? In this paper we refer to this econometrician’s problem as “E-invertibility” and consider the corresponding information problem of the agents in the assumed DGP, the DSGE model, which we refer to as “A-invertibility” We consider how the general nature of the agents’ signal extraction problem under imperfect information impacts on the econometrician’s problem of attempting to infer the nature of structural shocks and associated impulse responses from the data. We also examine a weaker condition of recoverability. A general conclusion is that validating a DSGE model by comparing its impulse response functions with those of a data VAR is more problematic when we drop the common assumption in the literature that agents have perfect information as an endowment. We develop measures of approximate fundamentalness for both perfect and imperfect information cases and illustrate our results using analytical and numerical examples

Production of strange particles at intermediate pT at RHIC

The recombination model is applied to the production of $K, \phi, \Lambda$ and $\Omega$ at all $p_T$ in central Au+Au collisions. The thermal-shower component of the recombination is found to be important for $K$ and $\Lambda$, but only in a minor way for $\phi$ and $\Omega$ in the intermediate to high $p_T$ region. The normalization and inverse slope of the thermal partons in the strange sector are determined by fitting the low-$p_T$ data. At higher $p_T$ the data of $K, \phi, \Lambda$ and $\Omega$ in the log scale are all well reproduced in our study that extends the thermal contribution and includes the shower contribution. The calculated result on the $\Lambda/K$ ratio rises to a maximum of around 2 at $p_T\approx 4$ GeV/c, arching over the data in linear scale. The production of $\phi$ and $\Omega$ are shown to arise mainly from the recombination of thermal partons, thus exhibiting exponential $p_T$ dependences in agreement with the data. Their ratio, $R_{\Omega/\phi}$, rises linearly to $p_T\approx 4$ GeV/c and develops a maximum at $p_T\approx 5.5$ GeV/c. It is argued that the $p_T$ spectra of $\phi$ and $\Omega$ reveal directly the partonic nature of the thermal source that characterizes quark-gluon plasma. Comments are made on the $\Omega$ puzzle due to the simultaneous observation of both the exponential behavior of the $\Omega$ spectrum in $p_T$ and the existence of low-$p_T$ particles associated with $\Omega$ as trigger.Comment: Revised manuscript with new figure

Final-State Interaction as the Origin of the Cronin Effect

Instead of adhering to the usual explanation of the Cronin effect in terms of the broadening of the parton transverse momentum in the initial state, we show that the enhancement of hadron production at moderate $p_T$ in d+Au collisions is due to the recombination of soft and shower partons in the final state. Such a mechanism can readily explain the decrease of the Cronin effect with increasing rapidity. Furthermore, the effect should be larger for protons than for pions.Comment: 4 RevTeX pages including 3 figures and 1 table; Some notational changes and a corrected referenc