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Process Systems Engineering developments in Europe from an industrial and academic perspective
No full textProcess Systems Engineering (PSE) is a discipline that deals with decision-making, at all levels and scales, by understanding any complex process system using a holistic view and a systems thinking framework. A closely related discipline (considered usually a part of PSE) is the Computer Aided Process Engineering (CAPE) which is a complementary field that focuses on developing methods and providing solution through systematic computer aided techniques for problems related to the design, control and operation of chemical systems. Nowadays, the ‘PSE’ term suffers from a branding issue to the point that PSE no longer gets the recognition that it deserves. In chemical engineering education the integrative systems frame for process design, control and operations is virtually absent. Its application potential in process industry lags relative to academic research progress and results. This work aims to provide an informative industrial and academic perspective on PSE (focused on the European region), arguing that the ‘systems thinking’ and ‘systems problem solving’ have to be given priority over just applications of computational problem solving methods. A multi-level view of the PSE field is provided within the academic and industrial context, and enhancements for PSE are suggested at their industrial and academic interfaces to create win-win situations
Collaboration between parents and SLTs produces optimal outcomes for children attending speech and language therapy - Gathering the evidence
No full textBackground: Collaboration between parents and speech and language therapists is seen as a key element in family-centred models. Collaboration can have positive impacts on parental and children’s outcomes. However, collaborative practice has not been well described and researched in speech and language therapy for children and may not be easy to achieve. It is important that we gain a deeper understanding of collaborative practice with parents, how it can be achieved, and how it can impact on outcomes. This understanding could support practitioners in daily practice with regard to achieving collaborative practice with parents in different contexts. Aims: The aim of this paper was to set a research agenda on collaborative practice between parents and speech and language therapists, in order to generate evidence regarding what works, how, for whom, in what circumstances, and to what extent.Methods: A realist evaluation approach was used to make explicit what collaborative practice with parents entails. The steps suggested by the RAMESES II project were used to draft a preliminary programme theory about collaborative practice between parents and speech and language therapists. This process generates explicit hypotheses which form a potential research agenda.Discussion and conclusion: A preliminary programme theory of collaborative practice with parents was drafted using a realist approach. Potential contextual factors (C), mechanisms (M) and outcomes (O) were presented which could be configured into causal mechanisms to help explain what works for whom in what circumstances. CMO configurations were drafted, based on relevant literature, which serve as exemplars to illustrate how this methodology could be used. In order to debate, test and expand our hypothesised programme theory for collaborative practice with parents, further testing against a broader literature is required alongside research to explore the functionality of the configurations across contexts. This paper highlights the importance of further research on collaborative practice with parents and the potential value of realist evaluation methodology
Clinical Guidance for the Management of Patients with Urothelial Cancers During the COVID-19 Pandemic – Rapid Review
No full textThe current COVID-19 pandemic presents a substantial obstacle to cancer patient care. Data from China as well as risk models suppose that cancer patients, particularly those on active, immunosuppressive therapies are at higher risks of severe infection from the illness. In addition, staff illness and restructuring of services to deal with the crisis will inevitably place treatment capacities under significant strain. These guidelines aim to expand on those provided by NHS England regarding cancer care during the coronavirus pandemic by examining the known literature and provide guidance in managing patients with urothelial and rarer urinary tract cancers. In particular, they address the estimated risk and benefits of standard treatments and consider the alternatives in the current situation. As a result, it is recommended that this guidance will help form a framework for shared decision making with patients. Moreover, they do not advise a one-size-fits-all approach but recommend continual assessment of the situation with discussion within and between centres
What are the barriers to physical activity in patients with chronic plaque psoriasis?
No full textBackgroundPsoriasis is associated with an increased risk of cardiovascular disease (CVD). Despite recommendation that exercise is important for cardiorespiratory fitness, patients with psoriasis avoid participation in physical activities for reasons which are, as yet, unclear.ObjectivesThis study investigated the relationship between psoriasis-specific experiences and self-reported patterns of exercise, hypothesising that individuals with psoriasis are less likely to engage in physical activity for reasons which are related to their psoriasis. Methods404 patients with chronic plaque psoriasis were recruited. History, examination and physical activity was assessed for each participant.Results52.8% (n=188) of patients with psoriasis aged 18 to 65 and 66.1% (n=37) of those over 65 engaged in less than the recommended amount of physical activity for cardiorespiratory fitness. As the severity and psychosocial impact of psoriasis increased the participation in exercise (of all intensities) decreased: significant negative correlation between Psoriasis Area and Severity Index and total activity in females aged 18 to 65 (r = -0.187, 95% confidence interval [CI] -0.36 - 0, p = 0.04), and significant negative correlation between physical activity and Dermatology Life Quality Index (DLQI) in all participants (r = -0.109, 95% CI -0.21 - 0, p = 0.04). Individual components of the DLQI identified barriers to physical activity including skin sensitivity and reluctance to participate in leisure activities.ConclusionPsoriasis-specific factors - severity, skin sensitivity, clothing choice, participation in social / leisure activities and treatments - contribute to exercise avoidance and may augment the increased risk of CVD in patients with psoriasis
A method for evaluating the bond behavior and anchorage length of embedded carbon yarn in the cementitious matrix
No full textThis paper presents a method for evaluating the bond behavior of a single carbon yarn embedded in the cementitious matrix. Pullout tests were carried out in which the carbon yarn was progressively pulled out of the matrix. It was found that all pullout specimens with a nominal bond length of 15 mm showed a similar pullout curve that is characterized by an initial ascending part and then a descending part followed by an almost constant part, along with the same failure mode due to the slippage of the carbon yarn out of the matrix. The proposed method was used to evaluate the bond parameters in the trilinear bond slip relationship, which has been demonstrated to be applicable for describing the interface between carbon yarn and the matrix. The reliability of the evaluation method has been substantiated by achieving good agreement between the analytical and the experimental results obtained from a range of pullout tests. For the embedded carbon yarn, an anchorage length can always be found so that the tensile capacity can be attained. Then, a proposed approach was used to directly determine the anchorage length of all the pullout specimens based on the evaluated trilinear bond--slip relationships, and the calculations were verified against the numerical results. In addition, a parametric study was carried out to investigate the effects of the bond parameters on the anchorage length of the embedded carbon yarn and showed that the anchorage length is influenced most by the local bond strength
Independent Core Rotation in Massive Filaments in Orion
No full textWe present high-angular-resolution ALMA (Atacama Large Millimeter Array) images of N2H+ (1– 0) that has been combined with those from the Nobeyama telescope toward OMC-2 and OMC-3 filamentary regions. The filaments (with typical widths of ∼ 0.1 pc) and dense cores are resolved. The measured 2D velocity gradients of cores are between 1.3 and 16.7 km s−1 pc−1, corresponding to a specific angular momentum (J/M) between 0.0012 and 0.016 pc km s−1 . With respect to the core size R, the specific angular momentum follows a power law J/M ∝ R1.52 ± 0.14. The ratio (β) between the rotational energy and gravitational energy ranges from 0.00041 to 0.094, indicating insignificant support from rotation against gravitational collapse. We further focus on the alignment between the cores’ rotational axes, which is defined to be perpendicular to the direction of the velocity gradient (θG), and the direction of elongation of filaments (θf ) in this massive star-forming region. The distribution of the angle between θf and θG was f ound to be random, i.e. the cores’ rotational axes have no discernible correlation with the elongation of their hosting filament. This implies that, in terms of angular momentum, the cores have evolved to be dynamically independent from their natal filaments
Optimized Anti-Windup Coordinating Strategy for Torque-maximized High-Speed Flux-weakening Operation of Constrained Induction Motor Drives
No full textDue to the contradiction between torque-maximized requirements and limited voltage and current constraints, voltage closed-loop flux-weakening strategy is developed to circumvent the saturation problem for maximum torque control of induction motor when the accelerating speed enters high-speed region. At the same time, since voltage inconsistency caused by the saturation is employed to construct flux-weakening controller (FC), anti-windup (AW) item in current regulator needs to be cut off to avoid the conflict. However, the replacement discards part of AW’s utility and results in the distortion of command voltage, thus compromising system’s dynamic performance and making the tuning process of PI-based FC much trickier. To address this issue, an equivalent saturation model is presented. An optimized AW coordinating strategy is proposed, combining a novel structure, so-called virtual voltage buffer, with FC. Through an equivalent proof, it can be transformed into over-modulation block for a convenient implementation. Through its compensation in the transient period, d-axis current can be quickly and smoothly manipulated in a more concise tuning process. As a result, the overall system possesses a fast acceleration capability with maximum torque and a wide speed range, while retaining a desirable system response. Simulation and experimental results verify the effectiveness of proposed method
Functionalized Graphene-based Polyamide Thin Film Nanocomposite Membranes for Organic Solvent Nanofiltration
No full textThis work deals with the use of octadecylamine (ODA)-functionalized reduced graphene oxide (rGO) for thin film nanocomposite (TFN) membranes. The functionalization of rGO with ODA leads to graphene-based nanofillers, more hydrophobic than GO, and thus to the easier dispersion in the organic phase of the interfacial polymerization (IP) reaction carried out to produce polyamide (PA) TFN membranes. The performance of the new TFN membranes is evaluated by organic solvent nanofiltration (OSN) of alcoholic solutions containing dyes Acridine Orange (AO, MW 265 gꞏmol-1), Sunset Yellow (SY, MW 452 gꞏmol-1) and Rose Bengal (RB, MW 974 gꞏmol-1). The functionalized nature of the nanoparticles introduced into the hydrophilic PA layer allow an increase of the ethanol permeance from 2.8, 3.4 and 3.7 Lꞏm-2ꞏh-1ꞏbar-1 for AO, SY and RB, respectively, corresponding to the bare thin film composite membrane (without rGO-ODA particles) to 4.3, 4.6 and 6.0 Lꞏm-2ꞏh-1ꞏbar-1 for AO, SY and RB, respectively, for the rGO-ODA based TFN membrane. In fact, we hypothesize that the increase of the ethanol flux achieved with the use of rGO-ODA as a filler in TFN membranes is owing to a combination of the simultaneous presence of polar and non-polar groups from rGO-ODA nanosheets and the creation of still selective narrow gaps between these particles and the polyamide (PA)
Rotorcraft Systems for Urban Air Mobility: A Reality Check
No full text“Urban air vehicles” have been hailed as the next revolution in aviation. Prototypes of various sizes have been flown to demonstrate basic flight (hover and climb), but in most cases there is no demonstration of full flight capability, for example conversion from vertical to level flight (conversion corridor). There are proposals for vehicles in a wide range of scales: from drones specifically designed to deliver goods, to full size vehicles for manned transportation.Most of the concepts proposed include full electric propulsion, multiple (often convertible) rotors (ducted or un-ducted, counter-rotating), and widespread use of composite materials. Start-up companies are seeking funding with high-profile demonstrations in front of themedia, but many unresolved technical problems are not been solved. Large aerospace companies have joined the fray. These initiatives are fuelling expectations that achieving the next milestone iswithin easy reach. This paper aims to fill some gaps in understanding and curb optimism. It takes a holistic viewin order to establish a scientific basis for design,manufacturing, operations.<br/
Decoupling or Learning: Joint Power Splitting and Allocation in MC-NOMA With SWIPT
No full textNon-orthogonal multiple access (NOMA) is one ofthe most significant technologies to meet the demand of high spectralefficiency (SE) in the fifth generation (5G) cellular networks.The utilization of simultaneous wireless information and powertransfer (SWIPT) contributes to prolonging the battery life of themobile users (MUs) and enhancing the system energy efficiency(EE), especially in the NOMA scenario where the inter-user interferencecan be reused for energy harvesting (EH). In this paper,we study the achievable data rate maximization problem forthe downlink multi-carrier NOMA (MC-NOMA) network withpower splitting (PS)-based SWIPT, in which power allocation andPS control are jointly optimized with the limitation of availablepower budget as well as the requirement for EH. The considerednon-convex optimization problem is arduous to tackle, resultingfrom the presence of the coupled variables and the inter-userinterference. To cope with the problem, a decoupled approachis developed, in which the power allocation and PS control areseparated and the corresponding sub-problems are respectivelysolved through Lagrangian duality method. Furthermore, analternative approach based on deep learning is proposed, which iscapable of effectively obtaining the approximate optimal solutionaccording to the empirical data. Simulation results confirm theeffectiveness of the proposed schemes, and demonstrate thesuperiority of the combination of PS-based SWIPT with MCNOMAover SWIPT-aided single-carrier NOMA (SC-NOMA)and SWIPT-aided orthogonal multiple access (OMA)