294 research outputs found

    A Role for Virtual Engineering in Engineering Skills Development

    Get PDF
    The paper will address how the Problem-Based-Learning (PBL) approach developed at Liverpool for undergraduate and graduate students has been extended to the continued professional development (CPD) of practising engineers. As the complexity of engineering systems grows, engineers increasingly need to be able to use a range of tools to undertake synthesis and analysis, address affordability goals, and reduce risk as they work in the various phases of the engineering life-cycle. To assist engineers operate successfully within this product life-cycle, there have been significant developments in modelling and simulation tools. Integrating these tools in a Virtual Engineering (VE) environment allows engineers to examine potentially conflicting requirements within the different phases of the life-cycle, to develop a co-ordinated approach to requirements capture and product design through to identifying costly problems that might occur later in the development and operations phases. Technical skills development to use these tools is critical in this process. This paper presents the experiences, learning outcomes and lessons gleaned in the development and implementation of bespoke rotorcraft engineering training programmes at The University of Liverpool. The programmes were designed using a Problem Based Learning (PBL) framework where knowledge and skills are gained through solving problems. Four cases studies are presented in the paper, demonstrating how this PBL/VE approach has been used effectively in training programmes. Consideration is given to the future use of VE tools, together with some challenges for their successful application

    Virtual Engineering in Skills Acquisition and Development in the Career of the Rotorcraft Engineer

    Get PDF
    As the complexity of engineering systems grows, engineers increasingly need to be able to use a range of tools in order to reduce the costs, and associated risks, as they work in the various phases of the engineering life-cycle. In order to help engineers operate successfully within this product lifecycle, there have been significant developments in modelling simulation tools. Integrating these tools in a Virtual Engineering (VE) environment allows engineers to examine the potentially conflicting requirements of the different phases of the life-cycle, to develop a co-ordinated approach to requirements capture and product design through to identifying potential costly problems that could occur later in the development and operations phases. Technical skills development to use these tools is key to this process. This paper presents the experiences, learning outcomes and lessons learned in the development and implementation of bespoke rotorcraft engineering training programmes. The programmes were designed using a Problem Based Learning (PBL) framework where knowledge and skills are gained through solving problems. Four cases studies are presented in the paper, demonstrating how this PBL/VE approach can be used in the training programmes. Consideration of the future use of VE tools is provided together with future challenges for their successful application

    Role of carbon allocation efficiency in the temperature dependence of autotroph growth rate

    Get PDF
    To predict how plant growth rate will respond to temperature requires understanding how temperature drives the underlying metabolic rates. Although past studies have considered the temperature dependences of photosynthesis and respiration rates underlying growth, they have largely overlooked the temperature dependence of carbon allocation efficiency. By combining a mathematical model that links exponential growth rate of a population of photosynthetic cells to photosynthesis, respiration, and carbon allocation; to an experiment on a freshwater alga; and to a database covering a wide range of taxa, we show that allocation efficiency is crucial for predicting how growth rates will respond to temperature change across aquatic and terrestrial autotrophs, at both short and long (evolutionary) timescales

    Earth pressure on cantilever walls at design retained heights

    Get PDF
    There are many methods for the analysis and design of embedded cantilever retaining walls. They involve various different simplifications of the pressure distribution to allow calculation of the limiting equilibrium retained height and the bending moment when the retained height is less than the limiting equilibrium value, i.e. the serviceability case. Recently, a new method for determining the serviceability earth pressure and bending moment has been proposed. This method makes an assumption defining the point of zero net pressure. This assumption implies that the passive pressure is not fully mobilised immediately below the excavation level. The finite element analyses presented in this paper examine the net pressure distribution on walls in which the retained height is less, than the limiting equilibrium value. The study shows that for all practical walls, the earth pressure distributions on the front and back of the wall are at their limit values, Kp and K-a respectively, when the lumped factor of safety F-r is less than or equal to2.0. A rectilinear net pressure distribution is proposed that is intuitively logical. It produces good predictions of the complete bending moment diagram for walls in the service configuration and the proposed method gives results that have excellent agreement with centrifuge model tests. The study shows that the method for determining the serviceability bending moment suggested by Padfield and Mair(1) in the CIRIA Report 104 gives excellent predictions of the maximum bending moment in practical cantilever walls. It provides the missing data that have been needed to verify and justify the CIRIA 104 method

    An experimental investigation of yarn tension in simulated ring spinning

    Full text link
    Yarn tension is a key factor that affects the efficiency of a ring spinning system. In this paper, a specially constructed rig, which can rotate a yarn at a high speed without inserting any real twist into the yarn, was used to simulate a ring spinning process. Yarn tension was measured at the guide-eye during the simulated spinning of different yarns at various balloon heights and with varying yarn length in the balloon. The effect of balloon shape, yarn hairiness and thickness, and yarn rotating speed, on the measured yarn tension, was examined. The results indicate that the collapse of balloon shape from single loop to double loop, or from double loop to triple etc, lead to sudden reduction in yarn tension. Under otherwise identical conditions, a longer length of yarn in the balloon gives a lower yarn tension at the guide-eye. In addition, thicker yarns and/or more hairy yarns generate a higher tension in the yarn, due to the increased air drag acting on the thicker or more hairy yarns

    Rehabilitation Exercise and psycholoGical support After covid-19 InfectioN' (REGAIN):a structured summary of a study protocol for a randomised controlled trial

    Get PDF
    OBJECTIVES The primary objective is to determine which of two interventions: 1) an eight week, online, home-based, supervised, group rehabilitation programme (REGAIN); or 2) a single online session of advice (best-practice usual care); is the most clinically and cost-effective treatment for people with ongoing COVID-19 sequelae more than three months after hospital discharge. TRIAL DESIGN Multi-centre, 2-arm (1:1 ratio) parallel group, randomised controlled trial with embedded process evaluation and health economic evaluation. PARTICIPANTS Adults with ongoing COVID-19 sequelae more than three months after hospital discharge Inclusion criteria: 1) Adults ≥18 years; 2) ≥ 3 months after any hospital discharge related to COVID-19 infection, regardless of need for critical care or ventilatory support; 3) substantial (as defined by the participant) COVID-19 related physical and/or mental health problems; 4) access to, and able/supported to use email and internet audio/video; 4) able to provide informed consent; 5) able to understand spoken and written English, Bengali, Gujarati, Urdu, Punjabi or Mandarin, themselves or supported by family/friends. EXCLUSION CRITERIA 1) exercise contraindicated; 2) severe mental health problems preventing engagement; 3) previous randomisation in the present study; 4) already engaged in, or planning to engage in an alternative NHS rehabilitation programme in the next 12 weeks; 5) a member of the same household previously randomised in the present study. INTERVENTION AND COMPARATOR Intervention 1: The Rehabilitation Exercise and psycholoGical support After covid-19 InfectioN (REGAIN) programme: an eight week, online, home-based, supervised, group rehabilitation programme. Intervention 2: A thirty-minute, on-line, one-to-one consultation with a REGAIN practitioner (best-practice usual care). MAIN OUTCOMES The primary outcome is health-related quality of life (HRQoL) - PROMIS® 29+2 Profile v2.1 (PROPr) - measured at three months post-randomisation. Secondary outcomes include dyspnoea, cognitive function, health utility, physical activity participation, post-traumatic stress disorder (PTSD) symptom severity, depressive and anxiety symptoms, work status, health and social care resource use, death - measured at three, six and 12 months post-randomisation. RANDOMISATION Participants will be randomised to best practice usual care or the REGAIN programme on a 1:1.03 basis using a computer-generated randomisation sequence, performed by minimisation and stratified by age, level of hospital care, and case level mental health symptomatology. Once consent and baseline questionnaires have been completed by the participant online at home, randomisation will be performed automatically by a bespoke web-based system. BLINDING (MASKING) To ensure allocation concealment from both participant and REGAIN practitioner at baseline, randomisation will be performed only after the baseline questionnaires have been completed online at home by the participant. After randomisation has been performed, participants and REGAIN practitioners cannot be blind to group allocation. Follow-up outcome assessments will be completed by participants online at home. NUMBERS TO BE RANDOMISED (SAMPLE SIZE) A total of 535 participants will be randomised: 263 to the best-practice usual care arm, and 272 participants to the REGAIN programme arm. TRIAL STATUS Current protocol: Version 3.0 (27th October 2020) Recruitment will begin in December 2020 and is anticipated to complete by September 2021. TRIAL REGISTRATION ISRCTN:11466448 , 23rd November 2020 FULL PROTOCOL: The full protocol Version 3.0 (27th October 2020) is attached as an additional file, accessible from the Trials website (Additional file 1). In the interests of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines

    Assessment of algorithms for mitosis detection in breast cancer histopathology images

    Get PDF
    The proliferative activity of breast tumors, which is routinely estimated by counting of mitotic figures in hematoxylin and eosin stained histology sections, is considered to be one of the most important prognostic markers. However, mitosis counting is laborious, subjective and may suffer from low inter-observer agreement. With the wider acceptance of whole slide images in pathology labs, automatic image analysis has been proposed as a potential solution for these issues. In this paper, the results from the Assessment of Mitosis Detection Algorithms 2013 (AMIDA13) challenge are described. The challenge was based on a data set consisting of 12 training and 11 testing subjects, with more than one thousand annotated mitotic figures by multiple observers. Short descriptions and results from the evaluation of eleven methods are presented. The top performing method has an error rate that is comparable to the inter-observer agreement among pathologists

    Telemonitoring based service redesign for the management of uncontrolled hypertension: multicentre randomised controlled trial

    Get PDF
    Objective To determine if an intervention consisting of telemonitoring and supervision by usual primary care clinicians of home self measured blood pressure and optional patient decision support leads to clinically important reductions in daytime systolic and diastolic ambulatory blood pressure in patients with uncontrolled blood pressure.Design Multicentre randomised controlled trial.Setting 20 primary care practices in south east Scotland.Participants 401 people aged 29-95 years with uncontrolled blood pressure (mean daytime ambulatory measurement ?135/85 mm Hg but ?210/135 mm Hg).Intervention Self measurement and transmission of blood pressure readings to a secure website for review by the attending nurse or doctor and participant, with optional automated patient decision support by text or email for six months.Main outcome measures Blinded assessment of mean daytime systolic ambulatory blood pressure six months after randomisation.Results 200 participants were randomised to the intervention and 201 to usual care; primary outcome data were available for 90% of participants (182 and 177, respectively). The mean difference in daytime systolic ambulatory blood pressure adjusted for baseline and minimisation factors between intervention and usual care was 4.3 mm Hg (95% confidence interval 2.0 to 6.5; P=0.0002) and for daytime diastolic ambulatory blood pressure was 2.3 mm Hg (0.9 to 3.6; P=0.001), with higher values in the usual care group. The intervention was associated with a mean increase of one general practitioner (95% confidence interval 0.5 to 1.6; P=0.0002) and 0.6 (0.1 to 1.0; P=0.01) practice nurse consultations during the course of the study.Conclusions Supported self monitoring by telemonitoring is an effective method for achieving clinically important reductions in blood pressure in patients with uncontrolled hypertension in primary care settings. However, it was associated with increase in use of National Health Service resources. Further research is required to determine if the reduction in blood pressure is maintained in the longer term and if the intervention is cost effectiv
    corecore