In this paper, a cellular relaying network consisting of two source-destination pairs, and four decode-and-forward relays operating in half-duplex mode is considered. Each source is assisted by two relays and all nodes are equipped with N antennas. In order to compensate for the loss of capacity by a factor of half due to the half-duplex mode, an alternate transmission protocol among the two relays is proposed. An outer bound on the degrees of freedom (DoF) of this system is developed. A constructive proof of achievability based on two different schemes is provided. Aligning the inter-relay
Subsequent duplication events are responsible for the evolution of the minisatellite maps. Alignment of two minisatellite maps should therefore take these duplication events into account, in addition to the well-known edit operations. All algorithms for computing an optimal alignment of two maps, including the one presented here, first deduce the costs of optimal duplication scenarios for all substrings of the given maps. Then, they incorporate the pre-computed costs in the alignment recurrence. However, all previous algorithms addressing this problem are dependent on the number of distinct
This paper introduces a dynamic model to adequately describe an Upflow Anaerobic Sludge Blanket (UASB) reactor. Some available models of a UASB reactor are discussed in order to modify their drawbacks and propose a new improved model with less complexity and more reliability. The developed model is a combination of two recent models introduced in Sweden. According to this model, a UASB rector is divided hydraulically into three compartments with integration of a kinetic model. Simulations are performed to investigate the validity of the developed model which indicates a good agreement with
This paper proposes generalized controllable strange attractors through dynamic rotation of fractional-order chaotic systems. Dynamic rotation angle enables the generation of multi-scroll and multi-wing attractors from single and double-scroll ones. The rotating systems are integrated with a generalized dynamic switched synchronization scheme. Dynamic control switches determine whether each system plays the role of master or slave. Based on dynamic scaling factors, the master can be one system or a combination of several ones with new strange attractors. The rotating fractional-order systems
This article proposes a new simple scheme for direct power control of a PWM rectifier without a switch table and voltage sensor. The selection of the switching state of the converter is based on the transition of a Petri net, using the instantaneous active and reactive power tracking errors and the angular position of the network line voltage estimated as variables of Controller input based on Petri nets. Simulation and experimental results demonstrated better performance and verified the validity of the new command with the Petri nets applied to the bridge rectifier connected to the
Multi-core and many-core Systems-on-Chip (SoC) are growing more complex than ever. Consequently, developing system models for such SoCs to guide and validate architectural and implementation decisions is becoming a daunting task. It consumes a huge amount of time and effort just to get the model up and running. Although these system models can be fairly abstracted, they still require the setup of a complicated platform to model a homogeneous or a heterogeneous mix of processing cores, a network-on-chip, cache memories, input-output interfaces as well as several other functional units. The
A major portion of the power consumed in today's systems is due to the clock distribution network. Solutions attempted to reduce clocking power result in low efficiency systems or systems with high complexity control schemes. In this work, a low power clock generator is introduced that can reduce switching power of the clock by almost 75%. This circuit uses the charge recycling concept to achieve such power reduction while utilizing a simple control technique. ©2010 IEEE.
[No abstract available]
A novel 4-D chaotic hyperjerk system with four quadratic nonlinearities is presented in this work. It is interesting that the hyperjerk system has no equilibrium. A chaotic attractor is said to be a hidden attractor when its basin of attraction has no intersection with small neighborhoods of equilibrium points of the system. Thus, our new non-equilibrium hyperjerk system possesses a hidden attractor. Chaos in the system has been observed in phase portraits and verified by positive Lyapunov exponents. Adaptive backstepping controller is designed for the global chaos control of the non
This chapter is intended to design and analyze several sliding mode techniques for the stabilization and synchronization of fractional order complex chaotic and hyperchaotic systems. Considering that chaos is a hot topic nowadays due to the vast number of real physical systems such as mechanical, electrical, and chemical systems in which this phenomenon is found; this book chapter will provide novel sliding mode approaches for the stabilization and synchronization of chaotic and hyperchaotic systems. Fractional order chaotic and hyperchaotic systems have been proved to be difficult to