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We successfully prepared Au nanoparticles using the modified polyol methods and design of experiments. The desirable crystal structure and particle size of Au nanoparticles with various kinds of polyhedral and spherical shapes as well as various kinds of their morphologies or complete and rough spherical crystal surfaces were experimentally predicted in TEM and XRD measurements according to the theoretical calculation and data. The fine crystal formation of Au nanostructures by modified polyol methods with EG, PVP, and NaBH4 is of great importance to their practical applications. Our research shows that the critical nucleation, growth, and formation of sizes, shapes, and morphologies of Au nanoparticles were experimentally discussed in modified polyol methods and design of experiments. In this context, our particle size calculation can hold the greatest attraction for researchers in the field of nanoparticles.

The requirements of low latency, low cost, less energy consumption, high flexibility, high network capacity, and high data safety are crucial challenges for future Internet of Things (IoT) wireless networks. Motivated by these challenges, this study deals with a novel design of green-cooperative IoT network, which employed coupled relays consisting of one IoT relay selected for forwarding signals to multiple IoT devices while another IoT relay transmitted jamming signals to an eavesdropper. For flexibility, all IoT nodes were powered by solar energy enough to sustain themselves, in order to consume less energy. To reach low latency, the study adopted the emerging non-orthogonal multiple access technique to serve multiple IoT devices simultaneously. Furthermore, the study adopted the simultaneous wireless information and power transfer technique which transmits wireless data for information processing and energy for energy harvesting. The study sketched a novel transmission block time period framework which plotted how a signal could travel via an individual IoT model. Maximizing the achievable bit-rate of IoT devices was considered to improve network capacity and data safety as well. Aiming at enhancing secrecy performance, a rest IoT relay played a role as a friendly jammer to transmit a jamming signal to an eavesdropper using energy harvested from the power splitting protocol. The results achieved in this study showed that the proposed model satisfied the requirements of future green IoT wireless networks. Derivatives leading to closed-form expressions are presented and verified by simulation results. The investigated results demonstrated that a friendly jammer based on radio frequency and energy harvesting strongly forces the intercept probability performance of the eavesdropper towards one, while outage probability performance of IoT devices towards zero showed that the signal to noise ratio tends to infinity.

In this research, we have mainly focused on the controlled synthesis, and properties of micro/nanosized ferrite and hexaferrite powders by the polyol process. They are Fe3O4-type Sr-Fe-O oxide and SrFe12O19 with the structure and magnetic properties by SEM, XRD, and VSM measurements. After heat treatment, it was discovered that Sr element was gradually fully incorporated into Fe3O4 for the formation of the original hexaferrite structure of SrFe12O19 at 950°C.

The controlled synthesis and paramagnetic properties of nanosized Zn–Fe–O oxides have been researched by the polyol and the heat treatment processes designed according to drying, annealing, and sintering from low to high temperatures. The structural changes have led to change weak superparamagnetism of nanosized Zn–Fe–O oxides in the forms of hybrid nanosized ZnO/ZnFe 2 O 4 oxides into paramagnetism of nanosized ZnFe 2 O 4 when the as-prepared samples of both ZnO and ZnFe 2 O 4 oxides were isothermally annealed and sintered from low temperature at about 60 °C to high temperature at 950 °C for 2 h during their structural phase transitions in all the measurements of x-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM) and SEM/energy dispersive X-ray spectroscopy (EDX) combined methods. Interestingly, it is experimentally confirmed that one original paramagnetic hysteresis consists of paramagnetic segments and closed curves. Both normal and abnormal paramagnetic properties of ZnFe 2 O 4 were carefully investigated.

In recent years, the development of intelligent reflecting surface (IRS) in wireless communications has enabled control of radio waves to reduce the detrimental impacts of natural wireless propagation. These can achieve significant spectrum and energy efficiency in wireless networks. Non-orthogonal multiple access (NOMA) technology, on the other hand, is predicted to improve the spectrum efficiency of fifth-generation and later wireless networks. Motivated by this reality, we consider the IRS-based NOMA network in the downlink and uplink scenario with a pernicious eavesdropper. Moreover, we investigated the physical layer security (PLS) of the proposed system by invoking the connection outage probability (COP), secrecy outage probability (SOP), and average secrecy rate (ASR) with analytical derivations. The simulation results reveal that (i) it is carried out to validate the analytical formulas, (ii) the number of meta-surfaces in IRS, transmit power at the base station, and power allocation parameters all play an essential role in improving the system performance, and (iii) it demonstrates the superiority of NOMA to the traditional orthogonal multiple access (OMA).

In this paper, the underlay cognitive radio network over mix fading environment is presented and investigated. A cooperative cognitive system with a secondary source node S, a secondary destination node D, secondary relay node Relay, and a primary node P are considered. In this model system, we consider the mix fading environment in two scenarios as Rayleigh/Nakagami-m and Nakagami-m/Rayleigh Fading channels. For system performance analysis, the closed-form expression of the system outage probability (OP) and the integral-formed expression of the ergodic capacity (EC) are derived in connection with the system's primary parameters. Finally, we proposed the Monte Carlo simulation for convincing the correctness of the system performance.

In this paper, the secrecy performance of the spatial modeling for ground devices with randomly placed eavesdroppers when an unmanned aerial vehicle (UAV) acted as two hops decode and forward (DF) was investigated. We characterize the secrecy outage probability (SOP) and intercept probability (IP) expressions. Our capacity performance analysis is based on the Rayleigh fading distributions. After analytical results by Monte Carlo simulation, and the Gauss-Chebyshev parameter was selected to yield a close approximation, the results demonstrate the SOP with the average signal-to-noise ratio (SNR) between UAV and ground users among the eavesdroppers and the IP relationship with the ability to intercept the information of the ground users successfully.

The controlled synthesis and paramagnetic properties of nanosized Zn-Fe-O oxides have been researched by the polyol and the heat treatment processes designed according to drying, annealing, and sintering from low to high temperatures. The structural changes have led to change weak superparamagnetism of nanosized Zn-Fe-O oxides in the forms of hybrid nanosized ZnO/ZnFe O oxides into paramagnetism of nanosized ZnFe O when the as-prepared samples of both ZnO and ZnFe O oxides were isothermally annealed and sintered from low temperature at about 60 °C to high temperature at 950 °C for 2 h during their structural phase transitions in all the measurements of x-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM) and SEM/energy dispersive X-ray spectroscopy (EDX) combined methods. Interestingly, it is experimentally confirmed that one original paramagnetic hysteresis consists of paramagnetic segments and closed curves. Both normal and abnormal paramagnetic properties of ZnFe O were carefully investigated.

In this research, we have mainly focused on the controlled synthesis, and properties of micro/nanosized ferrite and hexaferrite powders by the polyol process. They are Fe 3 O 4 -type Sr-Fe-O oxide and SrFe 12 O 19 with the structure and magnetic properties by SEM, XRD, and VSM measurements. After heat treatment, it was discovered that Sr element was gradually fully incorporated into Fe 3 O 4 for the formation of the original hexaferrite structure of SrFe 12 O 19 at 950°C.

A modified model reference adaptive controller for velocity control of a conveyor system in a fish sorting system with uncertainty parameters, input saturation and bounded disturbances is proposed in this article. In general, an asymptotic tracking can be achieved in model reference adaptive controller systems. However, a tracking performance of model reference adaptive controller controllers can be quite poor as an adaptation rate is increased. To improve the tracking performance and robustness of the proposed controller in the presence of bounded disturbances, the followings are done. First, the reference model in the conventional model reference adaptive controller is replaced by a modified reference model in a modified model reference adaptive controller to reduce unexpected high-frequency oscillation in control input signal when the adaptation rate is increased. Second, estimated parameters in an adaptive law can be varied smoothly under bounded external disturbances and a projection operator is utilized in an adaptive law for the proposed modified model reference adaptive controller to be robust. Third, an auxiliary error vector is introduced for compensating the error dynamics of the system when the saturation input occurs. Finally, the experimental results are shown to verify the better effectiveness and performance of the proposed controller under the bounded disturbance and saturated input than that of a conventional model reference adaptive controller.