Numerical analysis of the crack growth path in the cement mantle of the reconstructed acetabulum

In this study, we use the finite element method to analyze the propagation's path of the crack in the orthopedic cement of the total hip replacement. In fact, a small python statement was incorporated with the Abaqus software to do in loop the following operations: extracting the crack propagation direction from the previous study using the maximal circumferential stresses criterion, drawing the new path, meshing and calculating again (stresses and fracture parameters). The loop is broken when the user's desired crack length is reached (number of propagations) or the value of the mode I stress intensity factor is negative. Results show that the crack propagation's path can be influenced by human body posture. The existing of a cavity in the vicinity of the crack can change its propagation path or can absolutely attract it enough to meet it. Crack can propagate in the outward direction (toward the acetabulum bone) and cannot propagate in the opposite direction, the mode I stress intensity factor increases with the crack length and that of mode II vanishes.     

Effects of sulphurisation on vitamins (A,C and E) and malondialdehyde in apricots

In this study, the 1.0 m H₂SO₄ solution was used as a sulphur source to sulphurise apricots. Apricot samples were immersed into 1.0 m H₂SO₄ solution at room temperature for time of 30, 60 , 120, 180 and 240 min. Amounts of vitamins (A, C and E) and malondialdehyde (MDA) were determined as function of sulphurisation time and thus, sulphur content. It was determined that the optimum immersion time for sufficient sulphur content is 120 min. It is concluded that while amounts of vitamins decrease, the level of MDA increases with increasing immersion time and thus, sulphur contents.     

Analysis of vapor–gas bubbles in a single artery heat pipe

The noncondensable gas supported bubbles in an arterial heat pipe are studied. The governing conservation equations are solved to study the growth/collapse of spherical bubbles under different conditions by using the finite element method. The criterion used in the design of the venting pores to prime the artery is explained. The diffusion-limited bubble collapse in the condenser and bubble growth due to the phase change in the evaporator are both studied. A theoretical explanation for the capability of venting bubbles under different scenarios is provided. The experimental results, including rapid startup and condenser cooldown, are also presented to prove the ability of the heat pipes to vent vapor–gas bubbles.     

A novel solution of deep learning for sleep apnea detection: enhancement of SC and elimination of GVICS

Multimedia Tools and Applications - Convolutional neural network (CNN) classification has not achieved a medically-satisfied level of accuracy in sleep apnea detection due to the negative effect of...     

Main Effects Ensured by Symmetric Circular Slots Etched on the Radiating Patch of a Compact Monopole Antenna on the Impedance Bandwidth and Radiation Patterns

Wireless Personal Communications - Three compact monopole ultrawideband (UWB) antennas with half-wavelength symmetric circular slots etched on the radiating patch and operating in the UWB spectrum...     

Power-domain non orthogonal multiple access (PD-NOMA) in cooperative networks: an overview

Wireless Networks - Non-orthogonal multiple access (NOMA) scheme is emerging as a favourable multiple access scheme for future 5G networks. Compared to orthogonal multiple access techniques, NOMA...     

Study of the regenerator constituting material influence on a gamma type Stirling engine

A gamma Stirling engine with compressed air as working fluid was investigated. This engine operates at a maximum charge pressure of 10 bar, runs at a maximum rotation speed of 600 rpm and can provide 500 W of brake power on the shaft. The engine is equipped with several pressure sensors and thermocouples. This experimental study concentrates on the regenerator constituting material (porous medium). Four different materials were investigated: stainless steel, copper, aluminum and Monel 400. The obtained experimental results provide guidance to Stirling engine enhancement and selection of the appropriate regenerator material. As a conclusion, the regenerator has an important role to enhance the heat exchange and to improve Stirling engine performance, which closely depends on its constituting material.     

Highly-Directional,Highly-Efficient Solution-Processed Light-Emitting Diodes of All-Face-Down Oriented Colloidal Quantum Well Self-Assembly

Semiconductor colloidal quantum wells (CQWs) provide anisotropic emission behavior originating from their anisotropic optical transition dipole moments (TDMs). Here, solution-processed colloidal quantum well light-emitting diodes (CQW-LEDs) of a single all-face-down oriented self-assembled monolayer (SAM) film of CQWs that collectively enable a supreme level of IP TDMs at 92% in the ensemble emission are shown. This significantly enhances the outcoupling efficiency from 22% (of standard randomly-oriented emitters) to 34% (of face-down oriented emitters) in the LED. As a result, the external quantum efficiency reaches a record high level of 18.1% for the solution-processed type of CQW-LEDs, putting their efficiency performance on par with the hybrid organic-inorganic evaporation-based CQW-LEDs and all other best solution-processed LEDs. This SAM-CQW-LED architecture allows for a high maximum brightness of 19,800 cd m⁻² with a long operational lifetime of 247 h at 100 cd m⁻² as well as a stable saturated deep-red emission (651 nm) with a low turn-on voltage of 1.7 eV at a current density of 1 mA cm⁻² and a high J₉₀ of 99.58 mA cm⁻². These findings indicate the effectiveness of oriented self-assembly of CQWs as an electrically-driven emissive layer in improving outcoupling and external quantum efficiencies in the CQW-LEDs.