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The reliability of MUT is arguably sub-par. There has been very limited work on the reliability of MUT of corrosion as most of the research focused on MUT of weldments. The current body of literature showed a host of human factors that affected MUT, and a survey carried out on Non-destructive testing (NDT) personnel working in industry highlighted that two areas of concern were the task and the inspector. It is proposed that the use of a magnetic probe coupler (MPC) will aid the task and the inspector in carrying out a reliable MUT inspection. It will do this by ensuring that probe coupling is maintained to the Carbon Steel surface when working in a variety of positions while improving the tactility of scanning a component. It will greatly aid the monitoring of known areas of wall loss by ensuring that the probe is coupled consistently and accurately in the same position. The areas of wall loss can be easily marked when the technician is not manually trying to hold the probe to the test piece. The research will look to demonstrate the effectiveness of the MPC utilising it in corrosion inspections trials to validate the MPC.

A simulator was developed for modeling and designing multiple quantum wells structures such as quantum well infrared photodetectors and quantum cascade laser, based on a single-electron effective mass Schrödinger equation. It employs box integration finite differences and transfer matrix approaches to find energies of bound and scattering states in the structures. The graphical user interface allows the user to vary easily design parameters including effective mass, layer thickness and number of layers as well as simulation parameters in order to optimize the structure for different device applications and functionality. Three simulation examples were performed on: three coupled quantum wells structure, two-color asymmetric quantum well infrared photodetector structure and on a quantum cascade laser design. The results show an accuracy which is comparable to more complicated simulations.

There are different techniques used by Machine-to-machine (M2M) communications technologies to mitigate collision problem and data loss. One of these techniques is Frequency Hopping (FH), which is used by Weightless-N technology with a special random channel selection algorithm. In such a system, the probability of a message collision mainly depends on the randomisation algorithm used to access channels. This paper provides a novel randomisation algorithm for the channel selection process of the Weightless-N system. The new proposed algorithm is based on a uniform randomisation distribution and called a Uniform Randomisation Channel Selection Technique (URCST). This new algorithm provides a better system performance and lower probability of collision. In addition, it is faster and easier than the Mersenne Twister algorithm.

The effectiveness of a prepared composite metal-oxide (ZnO-CO2O3) to act as a reagent in ultra-violet photo-degradation bleaching of waste water is explored. This is achieved by the irradiation of the suspended solution inside 100 ml Pyrex photo-reaction cell using a Mercury lamp of 125 W at room temperature (298 K). It is found that the highest photocatalytic blenching of tannery waste water was observed at 0.1 g/100ml of composite ZnO – Co2O3. Photocatalytic bleaching of tannery waste water is shown to follow a first order reaction. Photocatalytic degradation process increases proportionally with temperature and the activation energy has been calculated to be approximately 28.74 kJ.mol -1. The addition of hydrogen peroxide (H2O2) enhances the photo-degradation mechanism reaching its maximum rate at a concentration of 0.04 millimoles.

Near-field ultrasonic response (50-2000 kHz) of an underwater 1-3 piezocomposite transducer is experimentally investigated using a polarimetric polarization maintaining fiber sensor. Measured outputs from our sensor and a reference hydrophone are observed to be comparable.