Vortex particle method for aerodynamic analysis: parallel scalability and efficiency

This paper presents an analysis of the scalability and efficiency of a simulation framework based on the Vortex Particle Method (VPM). The code is applied for the numerical aerodynamic analysis of line-like structures. The numerical code runs on multicore CPU and GPU architectures using OpenCL framework. The focus of this paper is the analysis of the parallel efficiency and scalability of the method being applied to an engineering test case, namely the aero-elastic response of a long-span bridge girder. The target is to assess the optimal configuration and the required computer architecture, such that it becomes feasible to efficiently utilize the method within the computational resources available for a regular engineering office. The simulations and the scalability analysis are performed on a regular gaming-type computer

Pengaruh Model Pembelajaran Conceptual Understanding Procedures (Cups) Berbantuan Lkpd Terhadap Kemampuan Pemecahan Masalah Fisika

This study aims to determine the effect of learning model Conceptual Understanding Procedures LKPD assisted on the ability of solving physics problems of high school students. This research is a quasi experimental research using untreated control group design with pretest and posttest. The population is all students of class XI IPA SMAN 4 Mataram. While the sampling using purposive sampling technique consisting of students class XI IPA 4 as experimental class and students of class XI IPA 1 as a control class. The problem solving capability data is obtained through a written test in the form of a description item. The result of hypothesis test analysis shows that there is influence of learning model of LKPD-assisted Conceptual Understanding Procedures toward the ability of problem solving physics

Investigation of the Structural Properties of Thermally Evaporated Aluminium Thin Films on Different Polymer Substrates.

This paper studies the properties of thermally evaporated 1 μm of aluminium (Al) thin films on polyimide (PI) and polyethylene terephthalate (PET) substrates at room temperature with thermal evaporation in a vacuum of about 3 x 10-5 Torr for use as window materials for solar cells. Effects of substrate types on the structural and electrical characteristics of the films were studied. Sets of experiments were conducted to optimize the deposition of Al films with appropriate deposition parameters. The deposited films were analyzed with atomic force microscopy (AFM), energy dispersive X-ray (EDX), X-ray diffraction (XRD). Energy dispersive X-ray (EDX) spectra shows presence of Al contacts on both PI and PET substrates. X-ray diffraction (XRD) results illustrate proper formation of Al (111) plane at 38.4o with full width at half maximum (FWHM) of 0.1968° on both samples. Atomic force microscope (AFM) images reveal that both samples possess smooth surfaces with surface roughness root mean square (RMS) below 10 nm

One-loop Neutron Electric Dipole Moment from Supersymmetry without R-parity

We present a detailed analysis together with exact numerical calculations on one-loop contributions to neutron electric dipole moment from supersymmetry without R-parity, focusing on the gluino, chargino, and neutralino contributions. Apart from the neglected family mixing among quarks, complete formulae are given for the various contributions, through the quark dipole operators, to which the present study is restricted. We discuss the structure and main features of the R-parity violating contributions and the interplay between the R-parity conserving and violating parameters. In particular, the parameter combination $\mu_i^*\lambda^{\prime}_{i11}$, under the optimal parametrization adopted, is shown to be solely responsible for the R-parity violating contributions in the supersymmetric loop diagrams. While $\mu_i^*\lambda^{\prime}_{i11}$ could bear a complex phase, the latter is not necessary to have a R-parity violating contribution.Comment: 43 pages Revtex with 15 eps- and 4 ps- figure files incoporated; proofread version to be published in Phys. Rev.

A generalized linear mixed model for longitudinal binary data with a marginal logit link function

Longitudinal studies of a binary outcome are common in the health, social, and behavioral sciences. In general, a feature of random effects logistic regression models for longitudinal binary data is that the marginal functional form, when integrated over the distribution of the random effects, is no longer of logistic form. Recently, Wang and Louis [Biometrika 90 (2003) 765--775] proposed a random intercept model in the clustered binary data setting where the marginal model has a logistic form. An acknowledged limitation of their model is that it allows only a single random effect that varies from cluster to cluster. In this paper we propose a modification of their model to handle longitudinal data, allowing separate, but correlated, random intercepts at each measurement occasion. The proposed model allows for a flexible correlation structure among the random intercepts, where the correlations can be interpreted in terms of Kendall's $\tau$. For example, the marginal correlations among the repeated binary outcomes can decline with increasing time separation, while the model retains the property of having matching conditional and marginal logit link functions. Finally, the proposed method is used to analyze data from a longitudinal study designed to monitor cardiac abnormalities in children born to HIV-infected women.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS390 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

On the EDM Cancellations in D-brane models

We analyze the possibility of simultaneous electron, neutron, and mercury electric dipole moment (EDM) cancellations in the mSUGRA and D--brane models. We find that the mercury EDM constraint practically rules out the cancellation scenario in D-brane models whereas in the context of mSUGRA it is still allowed with some fine-tuning.Comment: 10 pages, to appear in Phys. Rev. Let

ISAU - A potential tropical longan (Dihocarpus longan) of Sarawak

The longan fruit, imported from Thailand, has been much sought by Malaysian. This fruit tree will not bear fruit under the tropical condition~ of the Malaysian lowland. However in Sarawak there is a variant of the longan known by the vernacular name of ISAU, the fruit of which possesses thick aril which tastes better than the imported longan. This paper describes some of the results of investigation on the taxonomy, botany, propagation and other aspects of exploitation of the Isau fruit carried out by the Bintulu Campus of Universiti Pertanian Malaysia

Surface Electronic Structures and Field Emission Currents at Sodium Overlayers on Low-Index Tungsten Surfaces

The total energy distributions (TEDs) of the emission currents in field emission and surface photofield emission and the overlayer-induced modifications in the surface electronic structures from the technologically important W surfaces with the commensurate W(100)/Na c(2x2), W(110)/Na (2x2) and W(111)/Na (1x1) overlayers are calculated. The TEDs obtained by our recent numerical method that extends the full-potential linear augmented plane wave method for the electronic structures to the study of field and photofield emission are used to interpret the shifts of the peaks in the experimental TEDs in field emission and photofield emission from the W(100) and W(110) surfaces at sub-monolayer and monolayer Na coverage. Hybridization of the 3s Na states with the pairs of dz2-like surface states of the strong Swanson hump in clean W(100) and surface resonances in clean W(111) below the Fermi energy shifts these W states by about -1.2 eV and -1.0 eV, thus stabilizing these states, to yield new strong peaks in the TEDs in field emission and photofield emission from W(100)/Na c(2x2) and W(111)/Na (1x1) respectively. The effect of Na intralayer interactions are discussed and are shown to shift the strong s- and p-like peaks in the surface density of states of W(110) below and above the Fermi energy respectively to lower energy with increased Na coverage, in agreement with experiments.Comment: 12 page

A Resolution to the Supersymmetric CP Problem with Large Soft Phases via D-branes

We examine the soft supersymmetry breaking parameters that result from various ways of embedding the Standard Model (SM) on D-branes within the Type I string picture, allowing the gaugino masses and $\mu$ to have large CP- violating phases. One embedding naturally provides the relations among soft parameters to satisfy the electron and neutron electric dipole moment constraints even with large phases, while with other embeddings large phases are not allowed. The string models provide some motivation for large phases in the soft breaking parameters. The results generally suggest how low energy data might teach us about Planck scale physics.Comment: 11 pages, 2 eps figures; revised references and updated tex

Effects of CP Violation on Event Rates in the Direct Detection of Dark Matter

A full analytic analysis of the effects of CP violating phases on the event rates in the direct detection of dark matter in the scattering of neutralinos from nuclear targets is given. The analysis includes CP violating phases in softly broken supersymmetry in the framework of the minimal supersymmetric standard model (MSSM) when generational mixings are ignored. A numerical analysis shows that large CP violating phases including the constraints from the experimental limits on the neutron and the electron electric dipole moment (EDM) can produce substantial effects on the event rates in dark matter detectors.Comment: 17 pages, LaTex, including 2 figures; revised version to appear in the Physical Review