3,231 research outputs found
Review of Non-destructive Testing (NDT) Techniques and their applicability to thick walled composites
A tier 1 automotive supplier has developed a novel and unique kinetic energy recovery storage system for both retro-fitting and OEM application for public transport systems where periodic stop start behaviour is paramount. A major component of the system is a composite flywheel spinning at up to 36,000 rpm (600 Hz). Material soundness is an essential requirement of the flywheel to ensure failure does not occur. The component is particularly thick for a composite being up to 30 mm cross section in some places. The geometry, scale and material make-up pose some challenges for conventional NDT systems. Damage can arise in composite materials during material processing, fabrication of the component or in-service activities among which delamination, cracks and porosity are the most common defects. A number of non-destructive testing (NDT) techniques are effective in testing components for defects without damaging the component. NDT techniques like Ultrasonic Testing, X-Ray, Radiography, Thermography, Eddy current and Acoustic Emission are current techniques for various testing applications. Each of these techniques uses different principles to look into the material for defects. However, the geometry, physical and material properties of the component being tested are important factors in the applicability of a technique. This paper reviews these NDT techniques and compares them in terms of characteristics and applicability to composite parts
Moving from crime and punishment to success and reward: Transitioning from technical to educational research
Copyright © 2019: Sarah Dart, Kim Blackmore, Keith Willey, Anne Gardner, Smitha Jose, Raj Sharma, Sloan Trad, Lesley Jolly:. Many engineering academics interested in quality teaching and learning dabble with educational research. Some go further leaving their technical research field behind to embark head-long into what for many is an initially bewildering and conceptually challenging domain. Often peers perceive this transition as a crime (giving up on real engineering) liable to be punished with reduced access to funding and institutional recognition for one's research. The Australasian Association for Engineering Education (AAEE) has been sponsoring a Winter School in Engineering Education Research Methods since 2011, to help engineering academics change their transition story from one of crime and punishment to success and reward. While helpful, this transition is not a simple matter of learning new techniques but of altering one's perspective and habits of thinking and behaviour. Many participants find this both challenging and at least initially, a lonely pursuit. In this paper, participants in the 2018 school ask the question "what enables and hinders the transition to educational research"
Lay support for pregnant women with social risk: a randomised controlled trial
OBJECTIVES We sought evidence of effectiveness of lay support to improve maternal and child outcomes in disadvantaged families. DESIGN Prospective, pragmatic individually randomised controlled trial. SETTING Three Maternity Trusts in West Midlands, UK. PARTICIPANTS Following routine midwife systematic assessment of social risk factors 1324 nulliparous women were assigned, using telephone randomisation, to standard maternity care or addition of referral to a Pregnancy Outreach Worker (POW) service. Under 16 years and teenagers recruited to the Family Nurse Partnership trial were excluded. INTERVENTIONS Pregnancy Outreach Workers were trained to provide individual support and case management for the women including home visiting from randomisation to six weeks after birth. Standard maternity care (control) included provision for referring women with social risk factors to specialist midwifery services, available to both arms. MAIN OUTCOME MEASURES Primary outcomes were antenatal visits attended and Edinburgh Postnatal Depression Scale (EPDS) 8–12 weeks postpartum. Pre–specified, powered subgroup comparison was among women with two or more social risks. Secondary outcomes included maternal and neonatal birth outcomes; maternal self-efficacy and mother-to-infant bonding at 8-12 weeks; child development assessment at six weeks, breastfeeding at six weeks and immunisation uptake at 4 months, all collected from routine child health systems. RESULTS Antenatal attendances were high in the standard care control and did not increase further with addition of the POW intervention (10·1 versus 10·1 (MD) –0·00, 95% CI, (95% CI, –0·37, 0·37)). In the powered sub-group of women with two or more social risk factors, mean EPDS (MD –0·79 (95% CI, –1·56, –0·02) was significantly better, although for all women recruited no significant differences were seen (mean difference (MD) –0·59 (95% CI, –1·24, 0·06)). Mother-to-infant bonding was significantly better in the intervention group for all women (MD-0.30 (95% CI, -0.61, -0.00) p=0.05) and there were no differences in other secondary outcomes. CONCLUSIONS This trial demonstrates differences in depressive symptomatology with addition of the POW service in the powered sub-group of women with two or more social risk factors. Addition to existing evidence indicates benefit from lay interventions in preventing postnatal depression. This finding is important for women and their families given the known effect of maternal depression on longer term childhood outcomes
Chebyshev Type Inequalities Involving the Fractional Integral Operator Containing Multi-Index Mittag-Leffler Function in the Kernel
Recently, several authors have investigated Chebyshev type inequalities for numerous fractional integral operators. Being motivated by the work done by earlier researchers and their numerous applications in probability, transform theory, numerical quadrature, statistical problems and its significance in fractional boundary value problems. We aim to evaluate Chebyshev type inequalities involving fractional integral operator containing multi-index Mittag-Leffler function in the kernel. Admissible connections of the results mentioned in this article to those associated with previously established familiar fractional integral operators have been pointed out
Microperimetry as an outcome measure in RPGR-associated retinitis pigmentosa clinical trials
Purpose: To explore which microperimetry sensitivity index (pointwise sensitivity, mean sensitivity, and volume sensitivity) is suitable as a microperimetry outcome measure in patients with X-linked RPGR-associated retinitis pigmentosa (RP).
Methods: Microperimetry data from patients with RPGR-associated RP were collected and analyzed retrospectively. Fourteen participants completed triplicate microperimetry testing, across 2 consecutive days for the repeatability analyses. Longitudinal data was obtained from 13 participants who completed microperimetry testing at two separate visits.
Results: The test–retest coefficients of repeatability (CoR) for pointwise sensitivity were ±9.5 dB and ±9.3 dB, in the right and left eyes, respectively. The mean sensitivity CoR for the right and left eyes was ±0.7 dB and ±1.3 dB. Volume sensitivity CoR was ±144.5 dB*deg2 and ±324.2 dB*deg2 for the right and left eyes, respectively. The mean sensitivities were positively skewed toward zero in those with a high number of nonseeing points (arbitrarily assigned to −1.0 dB) and just seen points (0.0 dB). Volume sensitivities were unaffected by the averaging effects of skewed data.
Conclusions: Clinical trials should report population-specific test–retest variability to determine a clinically significant change. Pointwise sensitivity indices should be used with caution as outcome measures in clinical trials owing to high levels of test–retest variability. Global indices seem to be less prone to variability. Volume sensitivity indices seem to be superior for use in RPGR-associated RP clinical trials compared with mean sensitivity because they are unaffected by the averaging effects of highly skewed data.
Translational Relevance: Careful selection of sensitivity indices (VA) is required when using microperimetry as a clinical trial outcome measure
Development and feasibility testing of a smart phone based attentive eating intervention
BACKGROUND: Attentive eating means eating devoid of distraction and increasing awareness and memory for food being consumed. Encouraging individuals to eat more attentively could help reduce calorie intake, as a strong evidence base suggests that memory and awareness of food being consumed substantially influence energy intake. METHODS: The development and feasibility testing of a smartphone based attentive eating intervention is reported. Informed by models of behavioral change, a smartphone application was developed. Feasibility was tested in twelve overweight and obese volunteers, sampled from university staff. Participants used the application during a four week trial and semi-structured interviews were conducted to assess acceptability and to identify barriers to usage. We also recorded adherence by downloading application usage data from participants' phones at the end of the trial. RESULTS: Adherence data indicated that participants used the application regularly. Participants also felt the application was easy to use and lost weight during the trial. Thematic analysis indicated that participants felt that the application raised their awareness of what they were eating. Analysis also indicated barriers to using a smartphone application to change dietary behavior. CONCLUSIONS: An attentive eating based intervention using smartphone technology is feasible and testing of its effectiveness for dietary change and weight loss is warranted
Cold bonded pelletization of iron ore fines
Cold bonding processes have been developed with
a view to conserve energy in pellet hardening step.
The incorporation of the reductant and fluxes in
the pellet also ensures a blast furnace burden
that is hanogeneous with resultant smooth operations
of the furnace. The present paper deals with
the studies conducted on tha production of ccmposite
iron are pellets using iron are fines, leco char.
hydrated lime and natural silica flour as
well as rice husk silica. The results indicate
that the composite pellets with rice husk has
superior strength compared to the pellets with
natural crystalline form of silica. Studies on
CaO-HZD-rice husk silica reaction systffil revealed
that a gel like calciun silicate hydrate (CSH-I)
is formed during the steaming operation that is
responsible for the strengthaning of the composite
pellet. The studies on the kinetics of the hydrothermal
reaction revealed that the reaction is diffusion controlled and the product fanned is calcium silicate hydrate. The reducibility studies indicated good reducibility with minimun swelling
Feasibility and acceptability of regular weighing, setting weight gain limits and providing feedback by community midwives to prevent excess weight gain during pregnancy:randomised controlled trial and qualitative study
BACKGROUND: Regular weighing in pregnant women is not currently recommended in many countries but has been suggested to prevent excessive gestational weight gain. This study aimed to establish the feasibility and acceptability of incorporating regular weighing, setting maximum weight gain targets and feedback by community midwives. METHODS: Low risk pregnant women cared for by eight community midwives were randomised to usual care or usual care plus the intervention at 10–14 weeks of pregnancy. The intervention involved community midwives weighing and plotting weight on a weight gain chart, setting weight gain limit targets, giving brief feedback at each antenatal appointment and encouraging women to weigh themselves weekly between antenatal appointments. Women and midwives were interviewed about their views of the intervention. The focus of the study was on process evaluation. RESULTS: Community midwives referred 123 women and 115 were scheduled for their dating scan within the study period. Of these, 84/115 were approached at their dating scan and 76/84 (90.5 %) randomised. Data showed a modest difference favouring the intervention group in the percentage of women gaining excessive gestational weight (23.5 % versus 29.4 %). The intervention group consistently reported smaller increases in depression and anxiety scores throughout pregnancy compared with usual care. Most women commented the intervention was useful in encouraging them to think about their weight and believed it should be part of routine antenatal care. Community midwives felt the intervention could be implemented within routine care without adding substantially to consultation length, thus not perceived as adding substantially to their workload. CONCLUSIONS: The intervention was feasible and acceptable to pregnant women and community midwives and was readily implemented in routine care. TRIAL REGISTRATION: ISRCTN8160516
Recruitment of ethnic minority patients to a cardiac rehabilitation trial: The Birmingham Rehabilitation Uptake Maximisation (BRUM) study [ISRCTN72884263]
Background: Concerns have been raised about low participation rates of people from minority ethnic groups
in clinical trials. However, the evidence is unclear as many studies do not report the ethnicity of participants and
there is insufficient information about the reasons for ineligibility by ethnic group. Where there are data, there
remains the key question as to whether ethnic minorities more likely to be ineligible (e.g. due to language) or
decline to participate. We have addressed these questions in relation to the Birmingham Rehabilitation Uptake
Maximisation (BRUM) study, a randomized controlled trial (RCT) comparing a home-based with a hospital-based
cardiac rehabilitation programme in a multi-ethnic population in the UK.
Methods: Analysis of the ethnicity, age and sex of presenting and recruited subjects for a trial of cardiac
rehabilitation in the West-Midlands, UK.
Participants: 1997 patients presenting post-myocardial infarction, percutaneous transluminal coronary angioplasty
or coronary artery bypass graft surgery.
Data collected: exclusion rates, reasons for exclusion and reasons for declining to participate in the trial by ethnic
group.
Results: Significantly more patients of South Asian ethnicity were excluded (52% of 'South Asian' v 36% 'White
European' and 36% 'Other', p < 0.001). This difference in eligibility was primarily due to exclusion on the basis of
language (i.e. the inability to speak English or Punjabi). Of those eligible, similar proportions were recruited from
the different ethnic groups (white, South Asian and other). There was a marked difference in eligibility between
people of Indian, Pakistani or Bangladeshi origin
Principles And Practices Fostering Inclusive Excellence: Lessons From The Howard Hughes Medical Institute’s Capstone Institutions
Best-practices pedagogy in science, technology, engineering, and mathematics (STEM) aims for inclusive excellence that fosters student persistence. This paper describes principles of inclusivity across 11 primarily undergraduate institutions designated as Capstone Awardees in Howard Hughes Medical Institute’s (HHMI) 2012 competition. The Capstones represent a range of institutional missions, student profiles, and geographical locations. Each successfully directed activities toward persistence of STEM students, especially those from traditionally underrepresented groups, through a set of common elements: mentoring programs to build community; research experiences to strengthen scientific skill/identity; attention to quantitative skills; and outreach/bridge programs to broaden the student pool. This paper grounds these program elements in learning theory, emphasizing their essential principles with examples of how they were implemented within institutional contexts. We also describe common assessment approaches that in many cases informed programming and created traction for stakeholder buy-in. The lessons learned from our shared experiences in pursuit of inclusive excellence, including the resources housed on our companion website, can inform others’ efforts to increase access to and persistence in STEM in higher education
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