Sharif Digital Repository

Since multi-core processors have become a primary trend in processor development, new scheduling algorithms are needed to minimize power consumption while achieving the desired timeliness guarantees for multi-core real-time embedded systems. Although various power/energy efficient scheduling algorithms have recently been proposed, existing studies may have degraded run-time performance in terms of power/energy efficiency and real-time guarantees when applied to real-time embedded systems with uncertain execution time. Moreover, these algorithms are only provided for a specific set of tasks, while many industrial applications with real-time demands are composed of mixed sets of tasks with a... 

When heart failure occurred, revascularization to body’s organs and consequently covering the metabolic demands of different sections faces with problem. Chronic heart failure is the first reason of mortality all over the world. Traditional treatment for CHF at end stage is heart transplantation. But some of patients don’t have the opportunity to benefit from heart transplantation because of aging, health conditions and lack of donors. On the other hand, Left Ventricular Assist Devices that are using for supporting a ventricle suffering from failure face with basic chalanges for example, backflow in lower speeds and suction in higher speed. These constrictions necessitate maximum and minimum... 

Today's modern industrial control systems (ICS) and SCADA infrastructures, use industrial networks to communicate with the sensors and actuators installed in the field. In recent years the increase in use of standard protocols in this networks, and also the connection of industrial networks to the internet introduced new challenges in the area of industrial network security. The difference in the property, size, and requirements of this networks in comparison to legacy computer networks have made the legacy security solutions such as firewalls and IDS to not have enough efficiency. Some researches work on implementing new solution to meet the requirements of industrial networks in the area... 

Low back pain (LBP), the leading cause of disability worldwide, remains one of the most common and challenging occupational musculoskeletal disorders. The effective assessment of LBP injury risk, and the design of appropriate treatment modalities and rehabilitation protocols, require accurate estimation of the mechanical spinal loads during different activities. This study aimed to: 1) develop a novel 2D beam-column finite element control-based model of the lumbar spine and compare its predictions for muscle forces and spinal loads to those resulting from a geometrically-matched equilibrium-based model; 2) test, using the foregoing control-based finite element model, the validity of the... 

Microfluidics with the ability to control Nano-to-Pico meter volumes have caused the revolution in the systems of analytical biology and chemistry. However, the most Lab-On-Chip technologies (LOCs) depend on external control elements, so a lab is required to operate a chip. Bubble or drop logic through the bubble (drop) can control the flow internally and intrinsically digitally without utilizing of off-chip or moving components. Non-linearity is applied by using mutual drop-drop' effects on reversible linear flow in low Reynolds. for the proper exploitation of microfluidic systems, It is necessary to control droplet generation systems in one chip appropriately. The most crucial part of the... 

Programmable AC Power Supply is a part of any Grid Simulator. Grid simulator is a system that, as a voltage source, can produce various power grid voltage waveforms in the output, and as a load, can draw different currents of ordinary loads from the power grid. The application of Grid Simulators is testing many grid connected systems, such as chargers, power supplies, PV inverters and etc. The purpose of this thesis is to design and build a 3 kW Programmable AC power supply, which can be used as a part of a grid simulator in future works. In this thesis, back to back converter topology is used for implementation of the programmable AC power supply. This back to back converter consists of an... 

Classic controllers are designed to control the structure response at the desired thresholds concerning the minimum applied force by control elements. In some cases, the minimum applied force does not lead to the minimum energy consumption of the controlling system. Especially, the consumption energy of the semi-active control system is not linearly related to their applied force and their energy consumption is a nonlinear function of system dynamic variables. On the other hand, classic control algorithms are not optimized in the time domain of earthquakes and those are sub-optimal algorithms based on the structure's inherent characteristics. Time domain optimized algorithm control is an... 

Grid simulator is a system that, as a voltage source, can produce various current waveforms in power grid at its output, and also as a load, can draw different currents of different loads from the power grid. Grid simulators may be used for testing power grid connected systems, such as chargers, power supplies, etc. In this thesis the system is consisted of programmable AC current source, dual active bridge converter and back-to-back grid-tied inverter. Dual active bridge can normally operate while the current source is in different modes of function, such as constant current, constant power and constant impedance. Depending on the mode of function, the current at the DC link can behave...