Design of bandpass–bandpass diplexers using rectangular-, T-, and L-shaped resonators for hybrid power amplifier and 5G applications

Analog Integrated Circuits and Signal Processing - In this paper, two bandpass–bandpass diplexers, based on L-, T- and rectangular-shaped resonators are designed and analyzed, which are used...     

Fault detection in analogue circuits using hybrid evolutionary algorithm and neural network

With the development of analog integrated circuits technology and due to the complexity, and various types of faults that occur in analog integrated circuits, fault detection is a new idea, has been studied in recent decades. In this paper a three amplifier state variable filter is used as circuit under test (CUT) and, a hybrid neural network is proposed for soft fault diagnosis of the CUT. Genetic algorithm (GA) has the powerful ability of searching the global optimal solution, and back propagation (BP) algorithm has the feature of rapid convergence on the local optima. The hybrid of two algorithm will improve the evolving speed of neural network. GA-BP scheme adopts GA to search the optimal combination of weights in the solution space, and then uses BP algorithm to obtain the accurate optimal solution quickly. Experiment results show that the proposed GA-BP scheme is more efficient and effective than BP algorithm.     

The Electrolytic Ionic Strength Effect on Corrosion Resistance and Crystallinity of Plasma Electrolytic Oxidation (PEO) Coating Developed on Ti6Al4V

Protection of Metals and Physical Chemistry of Surfaces - The aim of this paper was to investigate the formation of an amorphous phase in the coating structure due to reduction in porosity and...     

Sr effect on the microstructure and tensile properties of A357 aluminum alloy and Al2O3/SiC-A357 cast composites

The effect of strontium as a modifier on the microstructures and tensile properties of two castable particulate metal matrix composites has been studied. The particulate metal matrix composites had similar matrix alloy (A357) but different reinforcing fine particles (silicon carbide and alumina). Results showed that the addition of 0.03% strontium makes a modest improvement to the yield strength, ultimate tensile strength and elongation percentage values, and the scatter of these properties, but makes a significant improvement to minimum strength and elongation results. Microstructural examinations by scanning electron microscope and energy dispersive spectroscopy analysis of metal matrix composites showed segregation of strontium on both the silicon carbide and alumina particles. Further results showed that the addition of higher strontium levels contributes to the over-modification of the eutectic silicon and promotes the formation of an Al–Si–Sr intermetallic compound on the particle/matrix interface.     

Effect of Oxide Bifilms on the Fracture Behavior of AM60B Mg Alloy

Transactions of the Indian Institute of Metals - The effect of entrained Mg oxide bifilms on the tensile properties and fracture behavior of AM60B Mg alloy was studied. For this purpose, tensile...     

Synthesis and characterization of electrospun cerium-doped bioactive glass/chitosan/polyethylene oxide composite scaffolds for tissue engineering applications

In this study, a series of electrospun chitosan/polyethylene oxide (PEO) nanofibrous scaffolds containing different amount of cerium-doped bioactive glasses (Ce-BGs) have been fabricated and proposed for tissue engineering applications. On a biological level, higher 8Ce-BG content significantly improved cytocompatibility of the scaffolds. Moreover, results of fibroblast cell culture study showed that greater 8Ce-BG content could enhance cell attachment and cell expansion on fiber mesh. Characterization of the scaffolds revealed that increasing 8Ce-BG content caused bioactive glass nanoparticles to agglomerate at a higher rate. The SEM mapping revealed thorough dispersion of submicrometric clusters in all areas of the polymeric matrix. Contact angle measurements showed that increasing 8Ce-BG/CH ratio from 0 to 10 (wt.%) improved wettability of the scaffold significantly. However, by increasing the ratio beyond 10 (wt.%), the wettability values decreased gradually. In conclusion, it was found that increasing 8Ce-BG/CH weight ratio up to 40 (wt.%) in the scaffold system was practical and useful for soft tissue engineering applications.     

Low-power high-speed phase frequency detector based on carbon nano-tube field effect transistors

A phase frequency detector (PFD) with a very low dead zone is proposed which is based on a configuration adaptable to both CMOS or carbon nano-tube transistors (CNTFETs). In the first step the proposed configuration is designed using CMOS transistors, and then CNTFETs are substituted to improve the speed and reduce the propagation delay. The proposed PFD in addition to very low dead zone, has low power consumption and high frequency range of operation, which are achieved as a result of the elimination of the reset path. The simulation results based on 32 nm technology for CNTFET and 180 nm technology for CMOS, illustrate that CNTFET-based proposed circuit dissipates 2 µW and has frequency of operation up to 30 GHz, and the dead zone equal to 1 ps. Compared to the conventional PFD based on CMOS technology, its dead zone and power consumption are lower. In addition, the effects of blocks’ parameters including the phase detector, which affect the operation of the phase locked loop, or delay locked loop, are systematically analyzed.

     

Effect of Cl– and $${\text{NO}}_{3}^{ - }$$ Ions on Microstructure and Properties of TiO2–CeO2 Nanostructured Composite Coatings Obtained Through Plasma Electrolytic Oxidation (PEO) on Ti6Al4V

Protection of Metals and Physical Chemistry of Surfaces - Rare earth cerium oxide synthesized from cerium (III) chloride and cerium (III) nitrate salts in electrolytes were used to develop...