Sharif Digital Repository

Sulfur doped and pure micro-nanoporous TiO2 film were synthesized with PEO method to produce a film with a high surface area for photocatalysis applications. The effect of applied voltage and electrolyte concentration on the microstructure and photocatalytic properties of the prepared layer were investigated via SEM, XRD, EIS and DRS studies. Electrochemical Impedance Spectroscopy (EIS) was carried out in order to determine the corrosion and electrochemical properties of the produced layer. It was found that although the barrier layer resistance decreases with the voltage, the layers porosity and consequently the surface area increases. Finally the XRD and DRS spectrums were correlated with... 

We propose an inexact nonmonotone successive quadratic programming (SQP) algorithm for solving nonlinear programming problems with equality constraints and bounded variables. Regarding the value of the current feasibility violation and the minimum value of its linear approximation over a trust region, several scenarios are envisaged. In one scenario, a possible infeasible stationary point is detected. In other scenarios, the search direction is computed using an inexact (truncated) solution of a feasible strictly convex quadratic program (QP). The search direction is shown to be a descent direction for the objective function or the feasibility violation in the feasible or infeasible... 

An inexact nonmonotone filter sequential quadratic programming algorithm is presented for solving general constrained nonlinear programming problems. At every iteration, a steering direction is computed as a minimizer of a linear model of the constraint violation over a trust region. A possible infeasible stationary point can be detected using the steering direction. If the current iterate is not an infeasible stationary point, a strongly convex feasible quadratic programming subproblem is defined to compute a search direction as an inexact solution satisfying some loose and achievable conditions. We prove that the search direction is a descent direction for the constraint violation or the... 

We propose an inexact nonmonotone successive quadratic programming (SQP) algorithm for solving nonlinear programming problems with equality constraints and bounded variables. Regarding the value of the current feasibility violation and the minimum value of its linear approximation over a trust region, several scenarios are envisaged. In one scenario, a possible infeasible stationary point is detected. In other scenarios, the search direction is computed using an inexact (truncated) solution of a feasible strictly convex quadratic program (QP). The search direction is shown to be a descent direction for the objective function or the feasibility violation in the feasible or infeasible... 

An inexact nonmonotone filter sequential quadratic programming algorithm is presented for solving general constrained nonlinear programming problems. At every iteration, a steering direction is computed as a minimizer of a linear model of the constraint violation over a trust region. A possible infeasible stationary point can be detected using the steering direction. If the current iterate is not an infeasible stationary point, a strongly convex feasible quadratic programming subproblem is defined to compute a search direction as an inexact solution satisfying some loose and achievable conditions. We prove that the search direction is a descent direction for the constraint violation or the... 

We propose an inexact nonmonotone successive quadratic programming (SQP) algorithm for solving nonlinear programming problems with equality constraints and bounded variables. Regarding the value of the current feasibility violation and the minimum value of its linear approximation over a trust region, several scenarios are envisaged. In one scenario, a possible infeasible stationary point is detected. In other scenarios, the search direction is computed using an inexact (truncated) solution of a feasible strictly convex quadratic program (QP). The search direction is shown to be a descent direction for the objective function or the feasibility violation in the feasible or infeasible... 

Quantum computing is an emerging and promising computational paradigm that provides substantial speedup for a variety of tasks such as integer factorization, database search, and machine learning. One of the quantum computation features is the possibility of developing quantum algorithms, which could be faster than algorithms developed for classic computers. However, we are still unable to fully realize a physical quantum computer and depend on traditional computers to simulate their behavior and test quantum algorithms. This is a source of complexity since one of the challenges to simulate quantum algorithms is the exponential memory requirement. In this work, we propose a method to... 

Quantum computing holds great promise for accelerating computational tasks, but they are still not accessible. To fill this gap, quantum computing simulators have been widely used for the developing of quantum circuits and algorithms. Simulating quantum algorithms on classical computers also poses challenges due to the need for exponential memory and computational requirements. Many researchers attempted to address such challenges on different single-core, multi-core, and many-core systems, especially graphics processing units (GPUs). The diversity of CPU and GPU simulation of quantum circuits, including various CPU–GPU combinations and multiple parameters, including qubit size, memory... 

This study aims to assess the impact of the spacing between cylinders on their dynamic behaviour. Observations during this experiment have helped to identify the effect of spacing on excitation mechanism of each cylinder as well as establishing the relationship between cylinders response and the spacing between them. Arrays of cylindrical Structures in close proximity are common in variety of engineering structures, particularly in the offshore industry. If the cylinders are flexible, and are subject to excitation from fluid flow, then the dynamics is influenced by complex interactions between the cylinders, dependent on a variety of parameters. Two cylinders were flexibly mounted in tandem... 

A nonlinear mathematical model is developed in the time domain to simulate the behaviour of two identical flexibly mounted cylinders in tandem while undergoing vortex-induced vibration (VIV). Subsequently, the model is validated and modified against experimental results. Placing an array of bluff bodies in proximity frequently happens in different engineering fields. Chimney stacks, power transmission lines and oil production risers are few engineering structures that may be impacted by VIV. The coinciding of the vibration frequency with the structure natural frequency could have destructive consequences. The main objective of this study is to provide a symplectic and reliable model capable... 

The elastic behavior of a screw dislocation which is positioned inside the shell domain of an eccentric core-shell nanowire is addressed with taking into account the surface/interface stress effect. The complex potential function method in combination with the conformal mapping function is applied to solve the governing non-classical equations. The dislocation stress field and the image force acting on the dislocation are studied in detail and compared with those obtained within the classical theory of elasticity. It is shown that near the free outer surface and the inner core-shell interface, the non-classical solution for the stress field considerably differs from the classical one, while... 

This paper studies the problem of receiver modeling in molecular communication systems. We consider the diffusive molecular communication channel between a transmitter nanomachine and a receiver nano-machine in a fluid environment. The information molecules released by the transmitter nano-machine into the environment can degrade in the channel via a first-order degradation reaction and those that reach the receiver nanomachine can participate in a reversible bimolecular reaction with receiver receptor proteins. Thereby, we distinguish between two scenarios. In the first scenario, we assume that the entire surface of the receiver is covered by receptor molecules. We derive a closed-form... 

Detrimental impacts of dust caused by mine tailings have yielded to several studies on the efficiency of different soil stabilizers. Bacterial stabilization has been recognized as a reality within recent decades, where bacteria could get adhesion to the grains and stabilize the soil particles. However, these bacteria are prone to be destroyed while exposed to the normal environmental conditions. In this study, the effects of microcapsules containing two types of bacterial freeze-dried spores (B.Subtilis Natto LMG 19457 and B.ESH) have been investigated on the mine tailing stability in terms of two parts. The first part of the study is dedicated to the fabrication of microcapsules within the...