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A number of digital signal processing (DSP) techniques are being applied to surface electromyography (SEMG) signals to extract detailed features of the signal. Fast Fourier transform (FFT) is one of the most common methods for analyzing the signal whether it is filtered or not. Another DSP technique is referred to as wavelet analysis, a method that is gaining more use in analyzing SEMG signals. This research focuses on using the discrete wavelet transform (DWT) and the wavelet package transform (WPT). Both DWT and WPT use analytical wavelets called "mother wavelet" which comes in different sets or "families". Wavelet analysis has the advantage over FFT as it provides the frequency contents of the signal over the time period that is being analyzed. SEMG signals were collected from a muscle under sustained contractions for 4 seconds with different loads. The raw signals were analyzed using FFT, DWT and WPT in LabVIEW(R) using its signal processing toolset. Using wavelet analysis the SEMG signal was decomposed into its frequency content form and then was reconstructed. In this paper the results are presented to show that certain families of mother wavelets of wavelet analysis are more suitable than others for analyzing SEMG signals.

Children with physical disabilities often have limited performance in daily activities, hindering their physical development, social development and mental health. Therefore, rehabilitation is essential to mitigate the adverse effects of the different causes of physical disabilities and improve independence and quality of life. In the last decade, robotic rehabilitation has shown the potential to augment traditional physical rehabilitation. However, to date, most robotic rehabilitation devices are designed for adult patients who differ in their needs compared to paediatric patients, limiting the devices’ potential because the paediatric patients’ needs are not adequately considered. With this in mind, the current work reviews the existing literature on robotic rehabilitation for children with physical disabilities, intending to summarise how the rehabilitation robots could fulfil children’s needs and inspire researchers to develop new devices. A literature search was conducted utilising the Web of Science, PubMed and Scopus databases. Based on the inclusion–exclusion criteria, 206 publications were included, and 58 robotic devices used by children with a physical disability were identified. Different design factors and the treated conditions using robotic technology were compared. Through the analyses, it was identified that weight, safety, operability and motivation were crucial factors to the successful design of devices for children. The majority of the current devices were used for lower limb rehabilitation. Neurological disorders, in particular cerebral palsy, were the most common conditions for which devices were designed. By far, the most common actuator was the electric motor. Usually, the devices present more than one training strategy being the assistive strategy the most used. The admittance/impedance method is the most popular to interface the robot with the children. Currently, there is a trend on developing exoskeletons, as they can assist children with daily life activities outside of the rehabilitation setting, propitiating a wider adoption of the technology. With this shift in focus, it appears likely that new technologies to actuate the system (e.g. serial elastic actuators) and to detect the intention (e.g. physiological signals) of children as they go about their daily activities will be required.

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This research focuses on proposing and evaluating an optimized hybrid system of wind and tidal turbines operating as a renewable energy generating unit in New Zealand. Literature review indicates increasing worldwide investment in offshore renewable energy in recent years. Offshore energy shows a high potential as an alternative energy generation solution to that of fossil fuels. Using the capacities of wind and tidal power in renewable technologies would be a suitable alternative for fossil fuels and would help prevent their detrimental effects on the environment. It is a cost-effective procedure for the power generation sector to maximize these renewables as a hybrid system. At the design phase, turbine types appropriate to environmental conditions for an area with high wind speed and tidal flow need to be considered. When selecting which turbines should be used, horizontal or vertical axis, number and length of blades, and optimized rotational speed are all important to get maximum capacity from either the wind or tidal energy for the hybrid system. Comprehensive simulation models of the hybrid system are now being set up, using several available commercial software packages such as QBlade, Simulink, and RETScreen. Several different parameters will be required for these simulation models to run in order to test performance, capacity and efficiency of the proposed hybrid system. To decide which regions are suitable for the hybrid system, it will be necessary to analyze available wind and tide records from NIWA, and online databases such as GLOBAL ATLAS. This next phase of research will aim to create optimized scenarios for the hybrid model by considering the effect of wind and water speed on performance. After deciding which region and scenarios are suitable, it will also be necessary to evaluate the costs and returns of a hybrid system. This final phase will be performed using the RETScreen simulation model.