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        1 - Performance Analysis of Device to Device Communications Overlaying/Underlaying Cellular Network
        Hossein  Ghavami Shahriar  Shirvani Moghaddam
        Minimizing the outage probability and maximizing throughput are two important aspects in device to device (D2D) communications, which are greatly related to each other. In this paper, first, the exact formulas of the outage probability for D2D communications underlaying More
        Minimizing the outage probability and maximizing throughput are two important aspects in device to device (D2D) communications, which are greatly related to each other. In this paper, first, the exact formulas of the outage probability for D2D communications underlaying or overlaying cellular network are derived which jointly experience Additive White Gaussian Noise (AWGN) and Rayleigh multipath fading. Then, simulation results of the exact formulas and previously respected approximate formulas are compared in MATLAB for both underlay and overlay scenarios. It is shown that the approximate formula in underlay scenario is a good estimate for exact one while approximate formula for overlaying scenario is a good approximation when the average distance between the transmit/receive nodes of D2D pair is less than half of the maximum distance between these nodes or variance of multipath fading is greater than 1.5. In addition, the probability density functions of Signal to Interference plus Noise Ratio (SINR) for underlay and overlay scenarios are found. Moreover, a new scenario is proposed which jointly considers overlay and underlay scenarios. Furthermore, exact and approximate formulas for outage probability and throughput of D2D users in the proposed scenario are derived. Finally, these formulas are compared to underlay and overlay scenarios in three special cases, low, moderate and high traffic loads Manuscript profile
      • Open Access Article

        2 - WSTMOS: A Method For Optimizing Throughput, Energy, And Latency In Cloud Workflow Scheduling
        Arash Ghorbannia Delavar Reza Akraminejad sahar mozafari
        Application of cloud computing in different datacenters around the world has led to generation of more co2 gas. In addition, energy and throughput are the two most important issues in this field. This paper has presented an energy and throughput-aware algorithm for sche More
        Application of cloud computing in different datacenters around the world has led to generation of more co2 gas. In addition, energy and throughput are the two most important issues in this field. This paper has presented an energy and throughput-aware algorithm for scheduling of compressed-instance workflows in things-internet by cluster processing in cloud. A method is presented for scheduling cloud workflows with aim of optimizing energy, throughput, and latency. In the proposed method, time and energy consumption has been improved in comparison to previous methods by creating distance parameters, clustering inputs, and considering real execution time. In WSTMOS method by considering special parameters and real execution time, we managed to reach the optimized objective function. Moreover, in the proposed method parameter of time distance of tasks to virtual machines for reduction of number of migration in virtual machines was applied. In WSTMOS method by organizing the workflow inputs to low, medium and heavy groups and also by distributing appropriate load on more suitable servers for processors threshold, we accomplished to optimize energy and cost. Energy consumption was reduced by 4.8 percent while the cost was cut down by 4.4 percent using this method in comparison to studied method. Finally, average delay time, power and workload are optimized in comparison to previous methods. Manuscript profile