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In this paper, the effects of different designs of pressure vessels on hydrodynamic parameters and the performance of seawater RO systems are investigated using computer simulations. Simulation results showed that designs using pressure vessels with four membranes in two-pass RO systems have a lower energy consumption, 5.29 and 0.33 kWh/m3 for the first and second passes, respectively, than those with two or three membranes. Also, designs No. 4 and No. 10 were the most efficient, 41 and 56% for the first and second passes, respectively, compared to other ones. The first and second passes required a lower permeate and feed pressure when using designs No. 3, No. 6, No. 9, and No. 12 where pressure vessels with two membranes were used. In addition, hybrid designs of two-pass RO systems were found to have the best efficiency and the lowest energy consumption among various other designs. Findings showed that in two-pass RO systems, the first pass consumes more energy than the second pass. Thus, the efficiency of the second pass in all designs of two-pass RO systems is more than the first pass. The results presented in this paper can be used to optimize the design of two-pass RO systems to ensure the optimum operation of such systems. [ABSTRACT FROM AUTHOR]

This paper proposes a novel free-weighting matrix (FWM) approach for the event-triggered (ET) consensus and formation control of multi-agent systems over a directed graph. A new FWM equality for the consensus error is proposed. This FWM is applied to attain coherent behavior of systems via a fully distributed ET approach. The proposed approach is also extended for ET formation control to attain a specific pattern of agents. Furthermore, an FWM-based consensus controller design with practical ET cooperative control is considered to address consensus and formation control problems by using the in-degree information of a node rather than the algebraic connectivity of a graph or adaptation of parameters. Additionally, the controller gain is formulated using a more general transformation compared to that used in classical approaches. Moreover, the proposed ET scheme for the designed controller is applied on the transmission side to preserve computational resources by eliminating the Zeno behavior. In contrast to the existing methods, the proposed approach (i) provides a fully distributed protocol without using central information of network or adaptive gain; (ii) provides a practical ET mechanism to assure effective bandwidth and fewer energy consumption; and (iii) can be applied to the ET formation problem for mobile agents. Simulations involving six aerial vehicles are performed to demonstrate the efficacy of the proposed cooperative control strategy. [ABSTRACT FROM AUTHOR]

Energy prices are booming to high levels with the ongoing global events and massive energy demand post-COVID, triggering panic among-st the general public. In this regard, energy demand management can play an important role here by letting both the entities (utility and customer) take control over the consumption pattern long enough until renewables take over the energy supply from the conventional resources using real-time device scheduling algorithms. To achieve this phenomenon, both participating entities need proper prioritization and their interests to be properly taken care of. In this paper sensitivity analysis of varying priorities to the objectives (customer cost and peak-to-average power ratio) representing both the entities has been carried out. A real-time device scheduling algorithm is implemented to improve the consumption pattern of appliances consisting of multiple objectives. Proper way of normalization is developed to retain the original essence of these objectives. The analysis embeds novel swap operations that are incorporated with standard particle swarm optimization (PSO) and its variants under varying pricing schemes. In order to demonstrate the proposed DR-based real-time optimization, a residence in Chicago, Illinois, USA is taken as a case study for this work. The results demonstrate the quickness and proper optimizations of the PSO variants with butterfly-PSO performing the best among-st the rest. Continuous real-time pricing obtained the best solution with apt quickness among-st its counterparts for each time-slot and for cumulative time of the day. An overall reduction in each entity's metrics is obtained in this work. [ABSTRACT FROM AUTHOR]

Nonorthogonal multiple access (NOMA) superposes several user signals for simultaneous transmission, considerably ameliorating spectral efficiency. To exploit efficiently radio frequency energy sources surrounding NOMA transmitters for improved energy efficiency, NOMA networks further employ energy harvesting, which practically possesses nonlinear characteristic. In addition, multiple antennas can be deployed at users to transfer-and-harvest energy efficiently and to transmit/receive information reliably with antenna array processing. As such, this paper evaluates numerically the throughput and the outage probability of NOMA networks accounting for practical factors such as nonlinear energy harvesting, all multi-antenna users, and imperfect channel information. Illustrative results expose that nonlinear energy harvesting and channel information imperfection considerably degrade system performance, which is governed flexibly by multiple parameters. Notably, NOMA networks can prevent a total outage and achieve the best performance with a proper parameter selection. Moreover, their performance is considerably ameliorated with accreting the number of antennas. [ABSTRACT FROM AUTHOR]

In the world of connected devices with enormous application market, wireless sensor network comes with inherent challenges. Energy consumption balancing among the sensors affects its lifetime and connectivity. A hybrid approach for the randomly deployed sensor network is proposed in this paper with better consumption energy balance through the lifetime of the sensor network. An optimized threshold probability is analyzed for the improvement of network lifetime in comparison with stable election protocol. Simulation results provide improved consumption energy distribution and prolonged network lifetime of heterogeneous wireless sensor network. The proposed protocol is reactive to the change in the network, making it suitable for the Internet of Things applications. [ABSTRACT FROM AUTHOR]