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...     

Behavior of 316L stainless steel containing corrosion pits under cyclic loading

The environmental performance of 316L grade stainless steel, in the form of tensile specimens containing a single corrosion pit with various aspect ratios, under cyclic loading in aerated chloride solutions is investigated in this study. Results from environmental tests were compared and contrasted with those obtained using finite element analysis (FEA). Fractography of the failed specimens obtained from experiments revealed that fatigue crack initiation took place at the base of the shallow pit. The crack initiation shifted towards the shoulder and the mouth of the pit for pits of increasing depth. This process is well predicted by FEA, as the strain contour maps show that strain is the highest around the centric strip of the pit. However, for shallow pits, local strain is uniformly distributed around that strip but begins to concentrate more towards the shoulder and the mouth region for increasingly deep pits.     

Calf massager: Intervention for body muscle discomfort during prolonged standing

Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage.     

Scattering of an induced surface electromagnetic field by fatiguecracks in ferromagnetic metals

In crack detection and sizing by the alternating current field measurement technique, U-shaped wires or coils excited by a high-frequency AC current source can be used to induce the surface field in the workpiece. The authors present a modeling technique for the interaction of a fatigue crack in a ferromagnetic metal with the surface field resulting from an inducer with two U-shaped wires. This work is an extension of a previous modeling technique to have developed for infinitely long (one-dimensional) cracks. In the present technique, the boundary of the fatigue crack is approximated by a circular arc, leading to a formulation for an efficient computation of the field-flaw interaction. Various numerical and experimental results supporting the modeling and illustrating the behavior of the magnetic field and electric potential at the metal surface around circular-arc cracks are presented     

High frequency capacitance measurements on metal–insulator–semiconductor structures in thermal non-equilibrium condition

We simulate the charge carrier traffic between the energy bands and the interface states in structures like Al/SiO₂/6H–SiC, Al/diamond/Si and Al/SIPOS/Si to explain their high frequency capacitance–voltage behavior. The structures have in common that traditional electrical measurement techniques performed at room temperature are prone to thermal non-equilibrium effects. This can result in large errors in the interface data extracted from such studies when thermal equilibrium conditions are assumed. In this work, high frequency capacitance–voltage data are compared to numerical simulations which include such thermal non-equilibrium conditions to enable more accurate estimates of interface state parameters in above-mentioned structures.     

Introduction

The Journal of Supercomputing -     

Optical and electrical characterization of CdS thin films

Thin CdS films have been grown by chemical bath (CdCl₂, thiourea, ammonia) deposition (CBD) on SnO₂ (TO)-coated glass substrate for use as window materials in CdS/CdTe solar cells. High-resolution transmission electron microscopy revealed grains with an average size of 10 nm. The structure was predominantly hexagonal with a high density of stacking faults. The film crystallinity improved with annealing in air. Annealing in a CdCl₂ flux increased the grain size considerably and reduced the density of stacking faults. The optical transmission of the as-deposited films indicated a band gap energy of 2.41 eV. Annealing in air reduced the band gap by 0.1 eV. Annealing in CdCl₂ led to a sharper optical absorption edge that remained at 2.41 eV. Similar band gap values were obtained by photocurrent spectroscopy and electroabsorption spectroscopy (EEA) using an electrolyte contact. EEA spectra were broad for the as-deposited and air-annealed samples, but narrower for the CdCl₂-annealed films, reflecting the reduction in stacking fault density. Donor densities of ca. 10¹⁷ cm ^–3 were derived from the film/electrolyte junction capacitance.     

Fully Petrov–Galerkin spectral method for the distributed-order time-fractional fourth-order partial differential equation

Distributed fractional derivative operators can be used for modeling of complex multiscaling anomalous transport, where derivative orders are distributed over a range of values rather than being just a fixed integer number. In this paper, we consider the space-time Petrov–Galerkin spectral method for a two-dimensional distributed-order time-fractional fourth-order partial differential equation. By applying a proper Gauss-quadrature rule to discretize the distributed integral operator, the problem is converted to a multi-term time-fractional equation. Then, the proposed method for solving the obtained equation is based on using Jacobi polyfractonomial, which are eigenfunctions of the first kind fractional Sturm–Liouville problem (FSLP), as temporal basis and Legendre polynomials for the spatial discretization. The eigenfunctions of the second kind FSLP are used as temporal basis in test space. This approach leads to finding the numerical solution of the problem through solving a system of linear algebraic equations. Finally, we provide some examples with smooth solutions and finite regular solutions to numerically demonstrate the efficiency, accuracy, and exponential convergence of the proposed method.

     

A mashup based framework for multi level healthcare interoperability

Healthcare delivery is evolving from disease-centered to patient-centered care delivery where patients are active participants in their healthcare delivery. This calls for more communication and collaboration among all healthcare actors. There is also an increasing demand for personalized healthcare systems that provide effective information management, facilitate communication and collaboration, and support applications to meet user requirements. To address these challenges, we need to advance the integration and interoperability of healthcare applications in a controlled manner. Drawing upon a conceptual model from a collaborative care case study, we identified a set of interoperability requirements and developed a Mashup based interoperability framework. Our framework allows patients and other healthcare actors to engage in collaborative processes through online applications facilitated by mashups. We then use proof-of-concept implementations to demonstrate how our framework is able to facilitate different types of interoperability. We believe that collaborative technologies such as mashups can implement process interoperability requirements to support collaborative care delivery, particularly for asynchronous care delivery.