4 research outputs found

    Simulation and retrofitting of mass exchange networks in fertilizer plants

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    Abstract This paper presents a simulation technique for optimizing a hydrogen integration network. By applying this technique, the minimum fresh hydrogen consumption can be determined. Quantitative relationship between sources and sinks streams were studied to get the flow rates of coupled source and sink, hydrogen consumption and hydrogen concentration in each stream. The introduced technique was applied on twelve sources and twelve sinks with any purity of hydrogen concentration. The hydrogen integration network was designed through two steps, the first step considers applying the data given in the LINGO program, while the second step considers using the LINGO results in the introduced excel program to obtain the retrofitted hydrogen integration network. The proposed technique was applied on several case studies to achieve the minimum consumption of fresh hydrogen for the obtained hydrogen integrated networks. The introduced model for simulation and retrofitting of mass exchange networks is easy to understand and the results showed that this model is more efficient for fertilizer, petrochemical and refinery plants

    Dynamical Analysis of Discrete-Time Two-Predators One-Prey Lotkaā€“Volterra Model

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    This research manifesto has a comprehensive discussion of the global dynamics of an achievable discrete-time two predators and one prey Lotkaā€“Volterra model in three dimensions, i.e., in the space R3. In some assertive parametric circumstances, the discrete-time model has eight equilibrium points among which one is a special or unique positive equilibrium point. We have also investigated the local and global behavior of equilibrium points of an achievable three-dimensional discrete-time two predators and one prey Lotkaā€“Volterra model. The conversion of a continuous-type model into its discrete counterpart model has been completed by adopting a dynamically consistent nonstandard difference scheme with the end goal that the equilibrium points are conserved in twin cases. The difficulty lies in how to find all fixed points O,P,Q,R,S,T,U,V and the Jacobian matrix and its characteristic polynomial at the unique positive fixed point. For that purpose, we use Mathematica software to find the equilibrium points and all of the Jacobian matrices at those equilibrium points. Moreover, we discuss boundedness conditions for every solution and prove the existence of a unique positive equilibrium point. We discuss the local stability of the obtained system about all of its equilibrium points. The discrete Lotkaā€“Volterra model in three dimensions is given by system (3), where parameters Ī±,Ī²,Ī³,Ī“,Ī¶,Ī·,Ī¼,Īµ,Ļ…,Ļ,Ļƒ,Ļ‰āˆˆR+ and initial conditions x0,y0,z0 are positive real numbers. Additionally, the rate of convergence of a solution that converges to a unique positive equilibrium point is discussed. To represent theoretical perceptions, some numerical debates are introduced, including phase portraits

    Dynamical Analysis of Discrete-Time Two-Predators One-Prey Lotka–Volterra Model

    No full text
    This research manifesto has a comprehensive discussion of the global dynamics of an achievable discrete-time two predators and one prey Lotka–Volterra model in three dimensions, i.e., in the space R3. In some assertive parametric circumstances, the discrete-time model has eight equilibrium points among which one is a special or unique positive equilibrium point. We have also investigated the local and global behavior of equilibrium points of an achievable three-dimensional discrete-time two predators and one prey Lotka–Volterra model. The conversion of a continuous-type model into its discrete counterpart model has been completed by adopting a dynamically consistent nonstandard difference scheme with the end goal that the equilibrium points are conserved in twin cases. The difficulty lies in how to find all fixed points O,P,Q,R,S,T,U,V and the Jacobian matrix and its characteristic polynomial at the unique positive fixed point. For that purpose, we use Mathematica software to find the equilibrium points and all of the Jacobian matrices at those equilibrium points. Moreover, we discuss boundedness conditions for every solution and prove the existence of a unique positive equilibrium point. We discuss the local stability of the obtained system about all of its equilibrium points. The discrete Lotka–Volterra model in three dimensions is given by system (3), where parameters α,β,γ,δ,ζ,η,μ,ε,υ,ρ,σ,ω∈R+ and initial conditions x0,y0,z0 are positive real numbers. Additionally, the rate of convergence of a solution that converges to a unique positive equilibrium point is discussed. To represent theoretical perceptions, some numerical debates are introduced, including phase portraits

    A High Gain Array Based Millimeter Wave MIMO Antenna With Improved Isolation and Decorrelated Fields

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    A high gain antenna system with improved isolation for 5G applications is proposed and investigated. The radiating structure consists of a combination of multiple strips to make the proposed design resonate within the desired frequency band of 28 GHz being of major interest for 5G applications. The antenna element provides 684 MHz operating bandwidth and a peak gain of 5.85 dB with a radiation efficiency of 70.9%. Using four antenna elements in an antenna array, connected with a T-shaped feeding network, provides a 12.5 dB peak gain and radiation efficiency of 91.5%. The efficiency improvement of almost 20% is achieved by the reducing transmission co-efficient in feed network elements. This also leads to a low side lobe level (SLL) and an improvement in the bandwidth to 1.53 GHz. Furthermore, the four-port multiple-input-multiple-output (MIMO) configuration is obtained using the proposed array configuration which gives an optimum gain, uncorrelated fields, reasonable bandwidth, and isolation of more than 30 dB with a satisfactory MIMO performance metrics. Due to the abovementioned promising features of presented design, it can be very useful for important 5G services
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