On Lebesgue measure of integral self-affine sets

Let $A$ be an expanding integer $n\times n$ matrix and $D$ be a finite subset of $Z^n$. The self-affine set $T=T(A,D)$ is the unique compact set satisfying the equality $A(T)=\cup_{d\in D} (T+d)$. We present an effective algorithm to compute the Lebesgue measure of the self-affine set $T$, the measure of intersection $T\cap (T+u)$ for $u\in Z^n$, and the measure of intersection of self-affine sets $T(A,D_1)\cap T(A,D_2)$ for different sets $D_1,D_2\subset Z^n$.Comment: 5 pages, 1 figur

Relating color discrimination to photopigment genes in deutan observers

AbstractDeutan observers are a heterogeneous group, varying nearly continuously from deuteranomalous trichromats with fine chromatic discrimination in the red/green range to deuteranopes who have none. We sought to relate chromatic discriminative ability among deutans measured psychophysically (phenotypes) to observers' separation between long-wave visual pigments inferred from visual pigment genes (genotypes). If middle-wave pigment genes are assumed not to be expressed in these deutan observers there is a clear relation between phenotype and genotype

Tuning the Level of Concurrency in Software Transactional Memory: An Overview of Recent Analytical, Machine Learning and Mixed Approaches

Synchronization transparency offered by Software Transactional Memory (STM) must not come at the expense of run-time efficiency, thus demanding from the STM-designer the inclusion of mechanisms properly oriented to performance and other quality indexes. Particularly, one core issue to cope with in STM is related to exploiting parallelism while also avoiding thrashing phenomena due to excessive transaction rollbacks, caused by excessively high levels of contention on logical resources, namely concurrently accessed data portions. A means to address run-time efficiency consists in dynamically determining the best-suited level of concurrency (number of threads) to be employed for running the application (or specific application phases) on top of the STM layer. For too low levels of concurrency, parallelism can be hampered. Conversely, over-dimensioning the concurrency level may give rise to the aforementioned thrashing phenomena caused by excessive data contention—an aspect which has reflections also on the side of reduced energy-efficiency. In this chapter we overview a set of recent techniques aimed at building “application-specific” performance models that can be exploited to dynamically tune the level of concurrency to the best-suited value. Although they share some base concepts while modeling the system performance vs the degree of concurrency, these techniques rely on disparate methods, such as machine learning or analytic methods (or combinations of the two), and achieve different tradeoffs in terms of the relation between the precision of the performance model and the latency for model instantiation. Implications of the different tradeoffs in real-life scenarios are also discussed

Layered hybrid phase Li2NaV2(PO4)3/carbon dot nanocomposite cathodes for Li+/Na+ mixed-ion batteries

Hybrid phase Li2NaV2(PO4)3 (H-LNVP) is one of the most promising cathode materials for Li+/Na+ mixed-ion batteries.</p

Gauging U(1) symmetries and the number of right-handed neutrinos

In this letter we consider that assuming: a) that the only left-handed neutral fermions are the active neutrinos, b) that $B-L$ is a gauge symmetry, and c) that the $L$ assignment is restricted to the integer numbers, the anomaly cancellation imply that at least three right-handed neutrinos must be added to the minimal representation content of the electroweak standard model. However, two types of models arise: i) the usual one where each of the three identical right-handed neutrinos has total lepton number L=1; ii) and the other one in which two of them carry L=4 while the third one carries $L=-5$.Comment: Published version in PLB forma

Ruling out the Modified Chaplygin Gas Cosmologies

The Modified Chaplygin Gas (MCG) model belongs to the class of a unified models of dark energy (DE) and dark matter (DM). It is characterized by an equation of state (EoS) $p_c = B\rho - A/\rho^{\alpha}$, where the case $B=0$ corresponds to the Generalized Chaplygin Gas (GCG) model. Using a perturbative analysis and power spectrum observational data we show that the MCG model is not a sucessful candidate for the cosmic medium unless $B=0$. In this case, it reduces to the usual GCG model.Comment: Latex file, 7 pages, 6 figures in eps forma

3D porous Li3V2(PO4)3/hard carbon composites for improving the rate performance of lithium ion batteries

A 3D porous Li3V2(PO4)3/hard carbon composite delivers a capacity of 98 mA h g−1 after 1000 cycles at 10C.</p

Yield conditions for deformation of amorphous polymer glasses

Shear yielding of glassy polymers is usually described in terms of the pressure-dependent Tresca or von Mises yield criteria. We test these criteria against molecular dynamics simulations of deformation in amorphous polymer glasses under triaxial loading conditions that are difficult to realize in experiments. Difficulties and ambiguities in extending several standard definitions of the yield point to triaxial loads are described. Two definitions, the maximum and offset octahedral stresses, are then used to evaluate the yield stress for a wide range of model parameters. In all cases, the onset of shear is consistent with the pressure-modified von Mises criterion, and the pressure coefficient is nearly independent of many parameters. Under triaxial tensile loading, the mode of failure changes to cavitation.Comment: 9 pages, 8 figures, revte

Observation of Two New N* Peaks in J/psi -> ppi−nˉp pi^- \bar n and pˉπ+n\bar p\pi^+n Decays

The $\pi N$ system in decays of $J/\psi\to\bar NN\pi$ is limited to be isospin 1/2 by isospin conservation. This provides a big advantage in studying $N^*\to \pi N$ compared with $\pi N$ and $\gamma N$ experiments which mix isospin 1/2 and 3/2 for the $\pi N$ system. Using 58 million $J/\psi$ decays collected with the Beijing Electron Positron Collider, more than 100 thousand $J/\psi \to p \pi^- \bar n + c.c.$ events are obtained. Besides two well known $N^*$ peaks at 1500 MeV and 1670 MeV, there are two new, clear $N^*$ peaks in the $p\pi$ invariant mass spectrum around 1360 MeV and 2030 MeV. They are the first direct observation of the $N^*(1440)$ peak and a long-sought "missing" $N^*$ peak above 2 GeV in the $\pi N$ invariant mass spectrum. A simple Breit-Wigner fit gives the mass and width for the $N^*(1440)$ peak as $1358\pm 6 \pm 16$ MeV and $179\pm 26\pm 50$ MeV, and for the new $N^*$ peak above 2 GeV as $2068\pm 3^{+15}_{-40}$ MeV and $165\pm 14\pm 40$ MeV, respectively

A numerical study of turbulent upward flow of super critical water in a 2×2 rod bundle with non-uniform heating

This work is part of a benchmarking excise organized by IAEA CRP in SCWR thermal-hydraulics aimed at improving the understanding and prediction accuracy of the thermal-hydraulic phenomena relevant to SCWRs. An experiment carried out using a 2x2 SCWR bundle at University of Wisconsin-Madison was modeled using an open-source Computational Fluid Dynamics (CFD) code - Code_Saturne. The k-w SST model was employed to account for the buoyancy-aided turbulent flow in the fuel channel. Significant heat transfer deterioration (HTD) was observed in the boundary layer, which is commonly expected to occur in buoyancy-aided flows. For comparison, simulations were also conducted using ANSYS FLUENT with similar model setups