94 research outputs found
Innovative STRoke Interactive Virtual thErapy (STRIVE) online platform for community-dwelling stroke survivors: a randomised controlled trial protocol
Introduction: The STRoke Interactive Virtual thErapy (STRIVE) intervention provides community-dwelling stroke survivors access to individualised, remotely supervised progressive exercise training via an online platform. This trial aims to determine the clinical efficacy of the STRIVE intervention and its effect on brain activity in community-dwelling stroke survivors.Methods and analysis: In a multisite, assessor-blinded randomised controlled trial, 60 stroke survivors >3 months poststroke with mild-to-moderate upper extremity impairment will be recruited and equally randomised by location (Melbourne, Victoria or Launceston, Tasmania) to receive 8 weeks of virtual therapy (VT) at a local exercise training facility or usual care. Participants allocated to VT will perform 3â5 upper limb exercises individualised to their impairment severity and preference, while participants allocated to usual care will be asked to maintain their usual daily activities. The primary outcome measures will be upper limb motor function and impairment, which will be assessed using the Action Research Arm Test and Upper Extremity Fugl-Meyer, respectively. Secondary outcome measures include upper extremity function and spasticity, as measured by the box and block test and Modified AshworthScale, respectively, and task-related changes in bilateral sensorimotor cortex haemodynamics during hand reaching and wrist extension movements as measured by functional near-infrared spectroscopy. Quality of life will be measured using the Euro-Quality of Life-5 Dimension-5 Level Scale, and the Motor Activity Log-28 will be used to measure use of the hemiparetic arm. All measures will be assessed at baseline and immediately postintervention
In-situ defect detection systems for R2R flexible PV films
The atomic layer deposition technique (ALD) is
used to apply a thin (40-100 nm thick) barrier
coating of Al2O3 on polymer substrates for flexible
PV cells, to minimise and control the degradation
caused by water vapour ingress. However,
defects appearing on the film surfaces during the
Al2O3 ALD growth have been seen to be highly
significant in deterioration of the PV module
efficiency and lifespan [1]. In order to improve the
process yield and product efficiency, it is
desirable to develop an inspection system that
can detect transparent barrier film defects in the
production line during film processing. Off-line
detection of defects in transparent PV barrier
films is difficult and time consuming.
Consequently, implementing an accurate in-situ
defects inspection system in the production
environment is even more challenging, since the
requirements on positioning, fast measurement,
long term stability and robustness against
environmental disturbance are demanding. For
in-situ R2R defects inspection systems the
following conditions need to be satisfied by the
inspection tools. Firstly the measurement must
be fast and have no physical contact with the
inspected film surface. Secondly the
measurement system must be robust against the
environmental disturbance inspection. Finally the
system should have sub-micrometre lateral
resolution and nanometre vertical resolution in
order to be able to distinguish defects on the film
surface. Optical interferometry techniques have
the potentially to be used as a solution for such
application. However they are extremely sensitive
to environmental noise such as mechanical
vibration, air turbulence and temperature drift.
George [2] reported that a single shot
interferometry system âFlexCamâ developed by
4D Technology being used currently to detect
defects for PV barrier films manufactured by R2R
technology. It is robust against environmental
disturbances; but it has a limited vertical range,
which is restricted by the phase ambiguity of the
phase shift interferometry. This vertical
measurement range (a few hundreds
nanometres) is far less than the normal vertical
range of defects (a few micrometres up to a few
tens micrometres). It is not possible to detect the
majority of defects in the R2R flexible PV barrier
films
In-situ defect detection systems for R2R flexible PV barrier films
Film processing procedures by means of Roll-to-Roll (R2R) for barrier coatings can often result in PV barrier films being manufactured with significant quantities of defects, which resulting in lower efficiency and a short life span. In order to improve the process yield and product efficiency it is desirable to develop an inspection system that can detect transparent barrier film defects in the production line during the film processing. Off-line detection of defect in transparent PV barrier films is difficult and time consuming. Consequently implementing an accurate in-situ defects inspection system in the production environment is even more challenging, since the requirements on positioning, fast measurement, long term stability and robustness against environmental disturbance are demanding. This paper reports on the development and deployment of two in-situ PV barrier films defect detection systems, one of them is based on wavelength scanning interferometry (WSI) and the other one is based on White Light Channeled Spectral Interferometry (WLCSI), and the integration into an R2R film processing line in the Centre for Process Innovation (CPI). The paper outlines the environmental vibration strategy for both systems and the developed auto-focussing methodology for WSI. The systems have been tested and characterised and initial results compared to laboratory-based instrumentation are presented
Metrology of Al2O3 Barrier Film for Flexible CIGS Solar Cells
Flexible Cu (In, Ga) Se2 (CIGS) solar cells are very attractive renewable energy sources because of their high conversion efficiencies, their low cost potential and their many application possibilities. However, they are at present highly susceptible to long term environmental degradation as a result of water vapor ingress through the protective encapsulation layer to the absorber (CIGS) layer. The basic methodology to prevent the water vapor permeation is to combine an oxide layer (e.g. AlOx) coating with suitable polymer substrates. Nevertheless, micro and nano-scale defects can appear at any stage of the coating process thus affecting the module efficiency and lifespan.
The main aim of this research paper is to use surface metrology techniques including: White Light Scanning Interferometry (WLSI), Atomic Force Microscopy (AFM) and Environmental Scanning Electron Microscopy (ESEM) to characterise the aluminum oxide (Al2O3) barrier film defects, which appear to be directly responsible for the water vapor permeability. This paper reports on the development of a characterisation method for defect detection based on âWolf Pruningâ method and then correlates this with measured water vapor transmission rates (WVTRs) using standard MOCONÂź test. The results presented in this paper provided a detailed knowledge of the nature of micro and nano-scale defects on the Al2O3 barrier films which are responsible for water vapor and oxygen ingress. This result can then be used to provide the basis for developing roll-to-roll in process metrology devices for quality control of flexible PV module manufacture
A flexible PV barrier films defects detection system for in-situ R2R film processing
R2R film processing procedures can often result in PV films being manufactured with a large quantity of defects, resulting in lower efficiency and a short life span. It is desirable to develop an in-situ PV barrier films defects detection system for R2R PV film manufacturing processes
Optical Fibre Sensors Using Graphene-Based Materials: A Review
Graphene and its derivatives have become the most explored materials since Novoselov and Geim (Nobel Prize winners for Physics in 2010) achieved its isolation in 2004. The exceptional properties of graphene have attracted the attention of the scientific community from different research fields, generating high impact not only in scientific journals, but also in general-interest newspapers. Optical fibre sensing is one of the many fields that can benefit from the use of these new materials, combining the amazing morphological, chemical, optical and electrical features of graphene with the advantages that optical fibre offers over other sensing strategies. In this document, a review of the current state of the art for optical fibre sensors based on graphene materials is presented
Inverse correlation between quasiparticle mass and Tc in a cuprate high-Tc superconductor
Close to a zero-temperature transition between ordered and disordered electronic phases, quantum fluctuations can lead to a strong enhancement of electron mass and to the emergence of competing phases such as superconductivity. A correlation between the existence of such a quantum phase transition and superconductivity is quite well established in some heavy fermion and iron-based superconductors, and there have been suggestions that high-temperature superconductivity in copper-oxide materials (cuprates) may also be driven by the same mechanism. Close to optimal doping, where the superconducting transition temperature Tc is maximal in cuprates, two different phases are known to compete with superconductivity: a poorly understood pseudogap phase and a charge-ordered phase. Recent experiments have shown a strong increase in quasiparticle mass m* in the cuprate YBa2Cu3O7-ÎŽ as optimal doping is approached, suggesting that quantum fluctuations of the charge-ordered phase may be responsible for the high-Tc superconductivity. We have tested the robustness of this correlation between m* and Tc by performing quantum oscillation studies on the stoichiometric compound YBa2Cu4O8 under hydrostatic pressure. In contrast to the results for YBa2Cu3O7-ÎŽ, we find that in YBa2Cu4O8, the mass decreases as Tc increases under pressure. This inverse correlation between m* and Tc suggests that quantum fluctuations of the charge order enhance m* but do not enhance Tc
Modelling water vapor permeability through atomic layer deposition coated photovoltaic barrier defects
Transparent barrier films such as Al2O3 used for prevention of oxygen and/or water vapour permeation are the subject of increasing research interest when used for the encapsulation of flexible photovoltaic modules. However, the existence of micro-scale defects in the barrier surface topography has been shown to have the potential to facilitate water vapour ingress, thereby reducing cell efficiency and causing internal electrical shorts. Previous work has shown that small defects (†3 Όm lateral dimension) were less significant in determining water vapour ingress. In contrast, larger defects (℠3 Όm lateral dimension) seem to be more detrimental to the barrier functionality. Experimental results based on surface topography segmentation analysis and a model presented in this paper, will be used to test the hypothesis that the major contributing defects to water vapour transmission rate are small numbers of large defects. The model highlighted in this study has the potential to be used for gaining a better understanding of photovoltaic module efficiency and performance
Growing up in Bradford:Protocol for the age 7-11 follow up of the Born in Bradford birth cohort
Background: Born in Bradford (BiB) is a prospective multi-ethnic pregnancy and birth cohort study that was established to examine determinants of health and development during childhood and, subsequently, adult life in a deprived multi-ethnic population in the north of England. Between 2007 and 2010, the BiB cohort recruited 12,453 women who experienced 13,776 pregnancies and 13,858 births, along with 3353 of their partners. Forty five percent of the cohort are of Pakistani origin. Now that children are at primary school, the first full follow-up of the cohort is taking place. The aims of the follow-up are to investigate the determinants of children's pre-pubertal health and development, including through understanding parents' health and wellbeing, and to obtain data on exposures in childhood that might influence future health. Methods: We are employing a multi-method approach across three data collection arms (community-based family visits, school based physical assessment, and whole classroom cognitive, motor function and wellbeing measures) to follow-up over 9000 BiB children aged 7-11 years and their families between 2017 and 2021. We are collecting detailed parent and child questionnaires, cognitive and sensorimotor assessments, blood pressure, anthropometry and blood samples from parents and children. Dual x-ray absorptiometry body scans, accelerometry and urine samples are collected on subsamples. Informed consent is collected for continued routine data linkage to health, social care and education records. A range of engagement activities are being used to raise the profile of BiB and to disseminate findings. Discussion: Our multi-method approach to recruitment and assessment provides an efficient method of collecting rich data on all family members. Data collected will enhance BiB as a resource for the international research community to study the interplay between ethnicity, socioeconomic circumstances and biology in relation to cardiometabolic health, mental health, education, cognitive and sensorimotor development and wellbeing.</p
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