Video Chat Application for Facebook

This project is mainly written for the facebook users. In today’s world, there are many social networking sites available. Among those social networking web sites, facebook is widely used web site. Like all other social networking web sites, Facebook also provides many features to attract more and more users. But it lacks in providing the most important feature of social networking, i.e. video chat. I explore the different options and requirements needed to build the video chat application. I have also described the integration of the application with the facebook

Short term optical variability in broad absorption line QSOs

We present the first results from a pilot programme to monitor the short term optical variability in Broad Absorption Line system QSOs. Intra-night optical variations of ~5% were detected on time scales of ~ one hour in QSOs 0846+156 and 0856+172. Further, the mean magnitude level decreased in the two objects by ~0.05 and ~0.15 magnitude respectively during the period of our observations. The observed light curves are quite similar to those previously seem in the flat spectrum radio-loud sources, especially the BL Lacertae objects, and can provide important constraints for the origin of microvariability, and also a possible evolutionary link between the radio-loud and the radio-quiet QSOs.Comment: 12 pages Latex file uses AASTEX, 2 Postscript figures. To appear in ApJ Letter

Respire: A Technological Tool to Navigate Mechanical Ventilation in Patient Care and Educational Settings

Around the world, more than 20 million patients rely on mechanical ventilators annually; however, not enough individuals understand how to operate ventilators, posing a risk to the health of many. Moreover, it is increasingly difficult to determine optimal mechanical ventilator settings in a timely fashion, especially in low-resource countries and critical care areas. Respire is a mobile application that bridges this gap in a twofold manner: it is designed to assist healthcare workers around the world navigate and use mechanical ventilators effectively as well as educate the general public about mechanical ventilation. Respire offers a user-friendly yet educational interface that quickly generates the most optimal ventilator settings based on the patient’s age, gender, weight, and health history. With limited information provided, Respire provides an individualized-patient model for optimal mechanical ventilation settings, including values generated for Positive End-Expiratory Pressure (PEEP), Respiratory Rate (RR), Tidal Volume (TV), and Trigger Sensitivity (TS). Developed entirely from scratch, this application was built in Android Studio IDE utilizing the programming language Java, and the graphical user interface as well as design components were created using XML and CSS. The desired outcomes of this program are to serve as an educational platform and a tool to supplement patient care related to medical respiration.https://scholarscompass.vcu.edu/uresposters/1441/thumbnail.jp

Nonlinear Random Response of Large-Scale Sparse Finite Element Plate Bending Problems

Acoustic fatigue is one of the major design considerations for skin panels exposed to high levels of random pressure at subsonic/supersonic/hypersonic speeds. The nonlinear large deflection random response of the single-bay panels aerospace structures subjected to random excitations at various sound pressure levels (SPLs) is investigated. The nonlinear responses of plate analyses are limited to determine the root-mean-square displacement under uniformly distributed pressure random loads. Efficient computational technologies like sparse storage schemes and parallel computation are proposed and incorporated to solve large-scale, nonlinear large deflection random vibration problems for both types of loading cases: (1) synchronized in time and (2) unsynchronized and statistically uncorrelated in time. For the first time, large scale plate bending problems subjected to unsynchronized load are solved using parallel computing capabilities to account for computational burden due to the simulation of the unsynchronized random pressure fluctuations. The main focus of the research work is placed upon computational issues involved in the nonlinear modal methodologies. A nonlinear FEM method in time domain is incorporated with the Monte Carlo simulation and sparse computational technologies, including the efficient sparse Subspace Eigen-solutions are presented and applied to accurately determine the random response with a refined, large finite element mesh for the first time. Sparse equation solver and sparse matrix operations embedded inside the subspace Eigen-solution algorithms are also exploited. The approach uses the von-Karman nonlinear strain-displacement relations and the classical plate theory. In the proposed methodologies, the solution for a small number (say less than 100) of lowest linear, sparse Eigen-pairs need to be solved for only once, in order to transform nonlinear large displacements from the conventional structural degree-of-freedom (dof) into the modal dof. Moreover, the linear and nonlinear matrices are stored using sparse storage schemes in order to save computational time and memory. In case of unsynchronized load case, the time history needs to be generated and also rescaled separately for each finite element. For problems with large mesh size, the numbers of elements are high and the generation of time histories makes the problem unsolvable (in terms of computational time and/or memory requirements) for all practical purposes. By implementing parallel processing techniques, large scale structural analysis problems are solved without resorting to the use of expensive computing equipment or incurring an inordinately high computational cost that leads to a feasible solution. The reduced and coupled nonlinear equations in modal dof are inexpensively solved by the familiar Runge Kutta numerical integration scheme. Accurate responses are ensured with modal convergence, mesh convergence, and time step studies. The obtained numerical results (for synchronized load case) have also been compared favorably with results obtained from commercialized F.E. code such as Abaqus. Small, medium and large-scale single bay panel models are used to validate and evaluate the numerical performance of the present formulation and its associated computer software

Classification of Radiology Reports Using Neural Attention Models

The electronic health record (EHR) contains a large amount of multi-dimensional and unstructured clinical data of significant operational and research value. Distinguished from previous studies, our approach embraces a double-annotated dataset and strays away from obscure "black-box" models to comprehensive deep learning models. In this paper, we present a novel neural attention mechanism that not only classifies clinically important findings. Specifically, convolutional neural networks (CNN) with attention analysis are used to classify radiology head computed tomography reports based on five categories that radiologists would account for in assessing acute and communicable findings in daily practice. The experiments show that our CNN attention models outperform non-neural models, especially when trained on a larger dataset. Our attention analysis demonstrates the intuition behind the classifier's decision by generating a heatmap that highlights attended terms used by the CNN model; this is valuable when potential downstream medical decisions are to be performed by human experts or the classifier information is to be used in cohort construction such as for epidemiological studies

Improving Access to Medicines in Poor Countries: The Role of Universities

Universities Allied for Essential Medicines, a coalition of students and faculty across North America, focuses on how academic research institutions can help to improve access to essential medicines

The Black Hole to Bulge Mass Relation in Active Galactic Nuclei

The masses of the central black holes in Active Galactic Nuclei (AGNs) can be estimated using the broad emission-lines as a probe of the virial mass. Using reverberation mapping to determine the size of the Broad Line Region (BLR) and the width of the variable component of the line profile H$\beta$ line it is possible to find quite accurate virial mass estimates for AGNs with adequate data. Compiling a sample of AGNs with reliable central masses and bulge magnitudes we find an average black-hole-to-bulge mass ratio of 0.0003, a factor of 20 less than the value found for normal galaxies and for bright quasars. This lower ratio is more consistent with the back hole mass density predicted from quasar light, and is similar to the central black hole/bulge mass ratio in our Galaxy. We argue that the black hole/bulge mass ratio actually has a significantly larger range than indicated by mssive black holes detected in normal galaxies (using stellar dynamics) and in bright quasars, which may be biased towards large black holes. We derive a scenario of black hole growth that explains the observed distribution.Comment: 12 pages LaTeX, including 2 revised figures, revised table. Revised version to be published in the Astrophysical Journal (Letters) Ap.J.Lett. 51

Deformation and crystallization of Zr-based amorphous alloys in homogeneous flow regime

The purpose of this study is to experimentally investigate the interaction of inelastic deformation and microstructural changes of two Zr-based bulk metallic glasses (BMGs): Zr_(41.25)Ti_(13.75)Cu_(12.5)Ni_(10)Be_(22.5) (commercially designated as Vitreloy 1 or Vit1) and Zr_(46.75)Ti_(8.25)Cu_(7.5)Ni_(10)Be_(27.5) (Vitreloy 4, Vit4). High-temperature uniaxial compression tests were performed on the two Zr alloys at various strain rates, followed by structural characterization using differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). Two distinct modes of mechanically induced atomic disordering in the two alloys were observed, with Vit1 featuring clear phase separation and crystallization after deformation as observed with TEM, while Vit4 showing only structural relaxation with no crystallization. The influence of the structural changes on the mechanical behaviors of the two materials was further investigated by jump-in-strain-rate tests, and flow softening was observed in Vit4. A free volume theory was applied to explain the deformation behaviors, and the activation volumes were calculated for both alloys