Entropic Interactions in Suspensions of Semi-Flexible Rods: Short-Range Effects of Flexibility

We compute the entropic interactions between two colloidal spheres immersed in a dilute suspension of semi-flexible rods. Our model treats the semi-flexible rod as a bent rod at fixed angle, set by the rod contour and persistence lengths. The entropic forces arising from this additional rotational degree of freedom are captured quantitatively by the model, and account for observations at short range in a recent experiment. Global fits to the interaction potential data suggest the persistence length of fd-virus is about two to three times smaller than the commonly used value of $2.2 \mu {m}$.Comment: 4 pages, 5 figures, submitted to PRE rapid communication

A Java Graphical User Interface for Large-Scale Scientific Computations in Distributed Systems

Large-scale scientific applications present great challenges to computational scientists in terms of obtaining high performance and in managing large datasets. These applications (most of which are simulations) may employ multiple techniques and resources in a heterogeneously distributed environment. Effective working in such an environment is crucial for modern large-scale simulations. In this paper, we present an integrated Java graphical user interface (IJ-GUI) that provides a control platform for managing complex programs and their large datasets easily. As far as performance is concerned, we present and evaluate our initial implementation of two optimization schemes: data replication and data prediction. Data replication can take advantage of \u27temporal locality\u27 by caching the remote datasets on local disks; data prediction, on the other hand, provides prefetch hints based on the datasets\u27 past activities that are kept in databases. We first introduce the data contiguity concept in such an environment that guides data prediction. The relationship between the two approaches is discussed

Dirac Cosmology and the Acceleration of the Contemporary Universe

A model is suggested to unify the Einstein GR and Dirac Cosmology. There is one adjusted parameter $b_2$ in our model. After adjusting the parameter $b_2$ in the model by using the supernova data, we have calculated the gravitational constant $\bar G$ and the physical quantities of $a(t)$, $q(t)$ and $\rho_r(t)/ \rho_b(t)$ by using the present day quantities as the initial conditions and found that the equation of state parameter $w_{\theta}$ equals to -0.83, the ratio of the density of the addition creation $\Omega_{\Lambda}=0.8$ and the ratio of the density of the matter including multiplication creation, radiation and normal matter $\Omega_m =0.2$ at present. The results are self-consistent and in good agreement with present knowledge in cosmology. These results suggest that the addition creation and multiplication creation in Dirac cosmology play the role of the dark energy and dark matter.Comment: 13 pages, 8 figure

Revenue-driven scheduling in drone delivery networks with time-sensitive service level agreements

Drones are widely anticipated to be used for commercial service deliveries, with potential to contribute to economic growth, estimated at £42 billion in the UK alone by the year 2030. Alongside air traffic control algorithms, drone-based courier services will have to make intelligent decisions about how to deploy their limited resources in order to increase profits. This paper presents a new scheduling algorithm for optimising the revenue of a drone courier service provider in these highly utilised time-sensitive service delivery systems. The first input to the algorithm is a monotonically decreasing value over time function which describes the service level agreement between the service provider and its customers. The second is the anticipated drone flight-time duration distribution. Our results show that the newly-developed scheduling algorithm, Least Lost Value, inspired by concepts for real-time computational workload processing, is able to successfully route drones to extract increased revenue to the service provider in comparison with two widely-used scheduling algorithms: First Come First Served and Shortest Job First, in terms of realised revenue

Understanding Psychophysiological Correlates of User Experience using Electroencephalogram (EEG)

The objective of this research is to understand psychophysiological correlates of user experience using electroencephalogram (EEG). We will conduct an experimental study to assess the psychophysiological differences across three states of user experience -- flow, boredom, and anxiety -- and compare them with the neutral state as a baseline. EEG measurement provides a plethora of data that can be decomposed using different analytical procedures. We will utilize one type of analysis, time-frequency decomposition, to examine changes in frequency (e.g., alpha/beta/theta band) over time. These frequency bands correlate with different cognitive states. In this study, we will use Event Related Spectral Perturbation (ERSP), a type of time-frequency decomposition, for its ability to model both time and frequency changes occurring in a frequency band. We expect the findings to not only contribute to a better understanding of psychophysiological means of assessing user experience, but also provide implications for future research in brain-computer interface

Geometry and topology of two kinds of extreme Reissner-Nordstro¨\ddot{o}m-anti-de Sitter black holes

Different geometrical and topological properties have been shown for two kinds of extreme Reissner-Nordstr$\ddot{o}$m-anti-de Sitter black holes. The relationship between the geometrical properties and the intrinsic thermodynamical properties has been made explicit.Comment: Latex, 12 pages, 4 figure

Non-CA resists for 193nm immersions lithography: Effects of chemical structure on sensitivity

Initial studies are presented on the use of polysulfones as non-chemically amplified resists (non-CARs) for 193 nm immersion lithography. Polynorbornene sulfone films on silicon wafers have been irradiated with 193 nm photons in the absence of a photo-acid generator. Chemical contrast curves and contrast curves were obtained via spectroscopic ellipsometry and grazing angle - attenuated total reflectance FTIR spectroscopy. Results were consistent with previously reported mechanisms for the degradation of aliphatic polysulfones with ionizing radiation. It was shown that E0 values could be reduced significantly by using a post exposure bake step, which propagated depolymerization of the polymer. Initial patterning results down to 50 nm half pitch were demonstrated with EUV photons

Properties of excitations in systems with a spinor Bose-Einstein condensate

General theory in case of homogenous Bose-Einstein condensed systems with spinor condensate is presented for the correlation functions of density and spin fluctuations and for the one-particle propagators as well. The random phase approximation is investigated and the damping of the modes is given in the intermediate temperature region. It is shown that the collective and the one-particle excitation spectra do not coincide fully.Comment: 5 pages, 1 figur

Geometry of the extreme Kerr black holes

Geometrical properties of the extreme Kerr black holes in the topological sectors of nonextreme and extreme configurations are studied. We find that the Euler characteristic plays an essential role to distinguish these two kinds of extreme black holes. The relationship between the geometrical properties and the intrinsic thermodynamics are investigated.Comment: Latex version, 10 page