An educational tool for enhanced mobile e-Learning for technical higher education using mobile devices for augmented reality

In all dimensions of education and all subjects, Smartphones have turned out to be broadly acknowledged technology. It plays an essential task in advanced online education systems. Because of smart devices� effortlessness and extension property, it is getting to be mandatory for portable applications. This paper analyses the research on Smart Devices (SD) to incorporate visual simulation into e-learning. The researchers created an Augmented Reality (AR) platform for e-learners to expand the coursebook with graphics and virtual multimedia applications. This paper recommends a Mobile e-Learning (MeL) application termed �MeL app. The advanced MeL app methods have been tested using Mann-Whitney �U� Test in the lecture hall using real-time learners. The proposed MeL app planned to create the learning practice easier, focusing on e-learner�s requirements by encouraging e-learners and instructor relationships to maintain communicative development-based e-learning for Technical Higher Education (THE). Software engineering learners assess this proposed framework in THE. Future work in this investigation incorporates new highlights, testing the device in extreme situations, evaluating the instructive perspectives utilizing more significant and increasingly various understudy and beginner inhabitants, and at last, extending the application space

A new rotating test facility for the experimental characterisation of shaft seals

Turbomachinery shaft seals suffer from rubs caused by thermal growth, assembly misalignment and rotor dynamic vibration at engine start-up and shut-down. Rubs are detrimental to performance, leading to a decrease in overall efficiency and costly corrective maintenance. In recent years, compliant seals have been developed, allowing for variable clearances and a reduced frequency of seal rubs. The design goal for compliant seals is therefore, to maintain a tight clearance between rotating and non-rotating parts, throughout the transient conditions experienced in engines. This paper presents the design of a new high-speed rotating test facility developed for the performance characterisation of turbine shaft seals. The rig features a 254 mm diameter rotor, capable of rotating at speeds of up to 15,000 rpm (equivalent to rotor surface speeds up to 200 m/s). The maximum pressure difference across a seal is 3.5 bar. In the first experimental campaign, the performance of a labyrinth seal was investigated. The rotordynamic coefficients of the seal were calculated by exciting the casing with an electromagnetic shaker. The leakage performance, direct and cross-coupled seal stiffnesses and effective damping coefficients are determined.</p

Use of vapochromic crystals to measure the concentration of a gaseous throughflow at the solid-fluid interface

This paper demonstrates the potential of vapochromic crystals as a sensing medium for measurements of local species concentration. Vapochromic crystals exhibit a reversible colour change based on the adsorption and desorption of water. As the water content of the crystals changes so too does the wavelength of light that they reflect (i.e. they change colour). In the situation where humid air mixes with a dry gas, the resulting specific humidity of the mixture can be related to the concentration level of the dry gas through a simple mass balance. As far as the authors are aware, this is the first time that vapochromic crystals have been used in this context. A number of the factors that affect the colour change of the crystal are investigated through simple flat plate experiments in a small wind tunnel. In all experiments, the hue and intensity of the vapochromic crystal was measured as a function of local dry gas concentration; in this case CO2. Green intensity levels exhibited the broadest activity over the widest range of CO2 levels, and was therefore used to quantify concentration. The crystals demonstrated a pronounced hysteresis, where the adsorption and desorption of water into the crystal structure was shown to occur at different concentration levels. The transition band was also shown to be highly temperature dependent when tested over a range of 22–44 °C. The vapochromic crystals were assessed for repeatability and found to sense the local CO2 concentration to ±1.5% CO2 over a range of green intensity values from 90 to 170. A practical example is presented to show how vapochromic crystals could be applied to the mixing of fluid streams in gas turbine film cooling.</p