Slicing of Web Applications Using Source Code Analysis

Program slicing revealed a useful way to limit the search of software defects during debugging and to better understand the decomposition of the application into computations. The web application is very widely used for spreading business throughout the world. To meet the desire of the customers, web applications should have more quality and robustness. Slicing, in the ?eld of web application, helps disclosing relevant information and understanding the internal system structure. This in turn helps in debugging, testing and in improving the program comprehensibility. The system dependence graph is an appropriate data structure for slice computation, in that it explicitly represents all dependencies that have to be taken into account in slice determination. We have extended the system dependence graph to Web-Application Dependence Graph (WADG). We have developed a partial tool for automatic generation of the WADG and computation of slices. In our literature survey, we found that most of the automatic graph generation tools are byte-code based. But, our tool uses the dependency analysis from the source code of the given program. We have presented three case studies by taking open source web programs and applying our techniques and slicing algorithm. We have found that the slices computed is correct and precise, which will be help full for program debugging and testing. Construction of the system dependence graph for Web applications is complicated by the presence of dynamic code. In fact, a Web application builds the HTML code to be transmitted to the browser at run time. Knowledge of such code is essential for slicing

Wave Phenomena In General Relativistic Magnetohydrodynamics

Here we study the wave propagation and stability of general relativistic non-resistive dissipative second-order magnetohydrodynamic equations in curved space-time. We solve the Boltzmann equation for a system of particles and antiparticles using the relaxation time approximation and the Chapman-Enskog-like gradient expansion for the off-equilibrium distribution function, truncating beyond second-order in curved space-time in electromagnetic fields. Unlike holographic calculation~\cite{Baier:2007ix}, we show that the viscous evolution equations do not explicitly depend on the curvature of space-time. Also, we have tested the causality and stability of the second-order theory in curved space-time in the presence of linearised metric perturbation and derived dispersion relations for various modes. Interestingly, we found the coupling of gravitational modes with the usual magneto-sonic modes in the small wave-number limit. Also, we show additional non-hydrodynamical modes arise due to gravity for a bulk-viscous fluid.Comment: 17 pages, 2 figure

Charged participants and their electromagnetic fields in an expanding fluid

We investigate the space-time dependence of electromagnetic fields produced by charged participants in an expanding fluid. To address this problem, we need to solve the Maxwell's equations coupled to the hydrodynamics conservation equation, specifically the relativistic magnetohydrodynamics (RMHD) equations, since the charged participants move with the flow. To gain analytical insight, we approximate the problem by solving the equations in a fixed background Bjorken flow, onto which we solve Maxwell's equations. The dynamical electromagnetic fields interact with the fluid's kinematic quantities such as the shear tensor and the expansion scalar, leading to additional non-trivial coupling. We use mode decomposition of Green's function to solve the resulting non-linear coupled wave equations. We then use this function to calculate the electromagnetic field for two test cases: a point source and a transverse charge distribution. The results show that the resulting magnetic field vanishes at very early times, grows, and eventually falls at later times.Comment: 13 pages, 5 figures. Minor revisions and a new figure showing domain of influence adde

A combined experimental-numerical framework for residual energy determination in spent lithium-ion battery packs

The present research proposes a combined framework that evaluates remaining capacity, material behavior, ions concentration of remaining metals, and current rate of chemical reactions of spent Li‐ion batteries accurately. Voltage, temperature, internal resistance, and capacity were studied during charging and discharging cycles. Genetic programming was applied on the obtained data to develop a model to predict remaining capacity. The results of experimental work and those estimated from model were found to be correlated, confirming the validation of model. Materials structure and electrochemical behavior of electrodes during cycles were studied by cyclic voltammetry, scanning electron microscopy, and energy dispersion spectrum

Optimization of Indoor Hybrid PLC/VLC/RF Communication Systems

In this work, we propose a hybrid power line communication (PLC)/visible light communication (VLC)/radio frequency (RF) fronthaul with a fiber based wired backhaul system to support massive number of smart devices (SDs). Since, a signal-to-noise ratio (SNR) based access point (AP) association and bandwidth (BW) allocation for each SD do not necessarily improve the system capacity, we propose novel and efficient AP association and BW allocation strategies to maximize the sum rate capacity (SRC) of the hybrid system under consideration. An optimization problem is formulated for the SRC with the AP association and BW allocation as the optimization parameters and a hierarchical decomposition method is used to convert the non-linear optimization problem into a set of convex optimization problems. Then, the proposed strategies are used to solve the optimization problem in an iterative manner till the SRC converges to an optimal value. Further, an analytical approximation for the BW allocated to each SD for a given AP association is derived using the Lagrangian multiplier method. The performance of the proposed system is evaluated through extensive numerical results. Moreover, the effect of the increased number of SDs on the optimal SRC is analysed