Reza Shiftehfar

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Saving energy is one of the principal challenges in wireless sensor networks. Dynamic voltage and frequency scaling (DVFS) is often used to reduce energy consumption in systems where sleep is not an option. We show that changing the CPU frequency introduces sudden changes in clock behavior, thereby affecting the time-keeping functionality. This anomalous(More)
In minor to moderate natural and man-made disasters, such as earthquakes and fires, people may be trapped inside buildings and hurt by the disaster. Considering that trapped victims may be unconscious, there is a high demand by emergency responders to get information on the locations and physical statuses of trapped victims inside a building during a(More)
Building energy-efficient systems is one of the principal challenges in wireless sensor networks. Dynamic voltage scaling (DVS), a technique to reduce energy consumption by varying the CPU frequency on the fly, has been widely used in other settings to accomplish this goal. In this paper, we show that changing the CPU frequency can affect timekeeping(More)
The fast growth of cloud applications highlights the requirement of appropriate security controls to restrict access to shared resources limited to authorized users. Existing authorization systems are not primarily designed for cloud environments and do not provide the required flexibility, adaptability, elasticity, scalability, or fine-grainedness of cloud(More)
Energy consumption is a key point of wireless sensor network. Wireless Sensor Networks (WSNs) introduces very special requirements in order to be efficient that is the energy consumption and the extension of the network’s lifetime. In this paper, we highlight the recent research efforts like energy efficient routing protocols, dynamic power management,(More)
Mobile Cloud Computing (MCC) overcomes mobile device limitations by delegating tasks to more capable cloud spaces. Existing mobile offloading solutions generally rely on full virtual machine migration, which is coarse-grained and costly, or implementation of code offloading as part of the application logic, which greatly increases the application complexity(More)
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