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Systematically review the literature with the primary aim of identifying behavioural interventions to improve vitamin D stores in children from at-risk ethnic groups.
Review based on PRISMA guidelines. PROSPERO registration number: CRD42017080932. Health Behaviour model and Behaviour Change Wheel Framework constructs used to underpin evaluation of interventions. Methodological quality evaluated using Cochrane Risk of Bias, Cochrane ROBINS-I, and NHLBI tools.
Databases Cochrane Library, MEDLINE, EMBASE, CINAHL with secondary search of Google Scholar. No country limits set. Papers between 1990-February 2018, published in English included. Anticipating study heterogeneity, outcome measures not pre-specified and identified from individual full papers. Updated literature search November 2020.
Patient or population including pregnant women, new-borns and children aged under 18 years, from Asian or African ethnic groups.
Of 10,690 articles screened, 298 underwent full text review, with 24 ultimately included for data extraction. All identified studies conducted a vitamin D pharmacological supplementation intervention, with two also incorporating a behavioural intervention strategy. No study explicitly defined a primary aim of evaluating a behavioural intervention, undertaken to study its effect on Vitamin D supplement uptake.
There is a need to address the paucity of data in ethnic at-risk children on how behavioural interventions, ideally developed and co-produced with the community under study, affect and help improve Vitamin D uptake, within the ante-natal and pregnancy phase as well as during childhood.
We provide a broad survey of methods for inversion relevant to waveforms, showing how inversions can be performed for models described by very large numbers of parameters. As are needed for seismic tomography We concentrate on numerical optimisation of a composite misfit function using descent methods . We discuss steepest descent, conjugate gradient, quasi-Newton and subspace methods providing specific algorithms and illustrations.
Shock control bumps can be used to control and weaken the shock waves that form on engine intakes at high angles of attack. In this paper, it is demonstrated how shock control bumps applied to an engine intake can reduce or eliminate shock-induced separation at high incidence, and also increase the incidence at which critical separation occurs. Three-dimensional Reynolds-average Navier–Stokes (RANS) simulations are used to model the flow through a large civil aircraft engine intake at high incidence. The variation in shock strength and separation with incidence is first studied, along with the flow distribution around the nacelle. An optimisation process is then employed to design shock control bumps that reduce shock strength and separation at a fixed high incidence condition. The bump geometry is allowed to vary in shape, size, streamwise position and circumferential direction around the nacelle. This is shown to be key to the success of the shock control geometry. A further step is then taken, using the optimisation methodology to design bumps that can increase the incidence at which critical separation occurs. It is shown that, by using this approach, the operating range of the engine intake can be increased by at least three degrees.
The objective of this study was to examine the activities, motivations, and barriers of activity engagement in the oldest-old residing in assisted living facilities (ALFs). Semi-structured interviews were conducted with 20 participants, aged 80–94 (standard deviation = 4.38), from two ALFs. Thematic analyses were used to identify and corroborate clusters of experiences. All residents stated that they desired enriching activities, most often in the form of productive work or community events. Although engaging in enriching activities was a universal desire, residents who experienced more functional limitations had an increased difficulty satisfying this need. Participants believed that activities offered by the ALF primarily served those who are cognitively impaired. ALF residents with severe mobility issues were not able to access more enriching activities outside the ALF compared to those with fewer physical limitations. However, the more physically impaired residents used a range of adaption methods that fit into the selection, optimisation, and compensation framework to overcome barriers to participate in meaningful activities. ALF residents who are cognitively fit but experience severe mobility limitations may be the most in need of enriching activities. To help these residents maintain a high quality of life, ALFs need to provide activities that appeal to residents of varying cognitive abilities and provide interventions to help aid their adaption to physical loss.
The aerodynamic performance of a deployable and low-cost unmanned aerial vehicle (UAV) is investigated and improved in present work. The parameters of configuration, such as airfoil and winglet, are determined via an optimising process based on a discrete adjoint method. The optimised target is locked on an increasing lift-to-drag ratio with a limited variation of pitching moments. The separation that will lead to a stall is delayed after optimisation. Up to 128 design variables are used by the optimised solver to give enough flexibility of the geometrical transformation. As much as 20% enhancement of lift-to-drag ratio is gained at the cruise angle-of-attack, that is, a significant improvement in the lift-to-drag ratio adhering to the preferred configuration is obtained with increasing lift and decreasing drag coefficients, essentially entailing an improved aerodynamic performance.
In this Research Communication we describe the optimisation of spray drying conditions in the production of microencapsulated cream powder. Oil-in-water emulsions were prepared using maltodextrin (18 DE) and sodium caseinate as wall materials (with the total wall material per total solid content ratio of 30%) and then converted into powder by spray drying. Response surface methodology was used to optimise the factors of spray drying system i.e. inlet drying temperature, feed flow rate, and aspiration rate, where the levels were in the range of 150–190°C, 9–30 ml/min, and 50–100%, respectively. Our objective was to perform spray drying with the highest drying yield and to obtain a microencapsulated cream powder with the highest bulk density, the shortest wetting time, and the lowest surface fat content. The calculated and validated optimum conditions for the spray drying process were found to be 162.8°C for inlet drying temperature, 11.51 ml/min for feed flow rate, and 72.8% for aspiration rate. At these optimum conditions, drying yield, bulk density, wettability, and surface fat content values were 36.37%, 269.9 kg/m3, 115.2 s and 26.2%, respectively.
Electric vehicles are playing an increasingly important role in the agricultural sector. The selection of tyres for reducing energy loss due to rolling resistance is an important consideration in determining the viability of these vehicles. To date little is known about rolling resistance of small all-terrain vehicles. In this study a test rig was used to collect rolling resistance data for seven ATV tyres. The study verifies the relationship between normal load and rolling resistance and gives insight into some of the important considerations when selecting tyres for small off road vehicles.
The work aims at the definition of a design methodology able to drive designers in the definition of product architectures, starting from rough information available at the conceptual design. The methodology identifies design guidelines useful for the development of product architectures optimized for a given target (i.e. assembly, cost). The methodology is based on domains which combine attributes related to a specific aspect of the target. The exploratory application of the methodology was performed to address the equipment installation of a civil aircraft for assembly/installation target.
This paper describes an approach for designing lightweight components produced through additive manufacturing (AM). Lightweight design is often done through topology optimization (TO). However, the process of manually interpreting mesh-based and imprecise results from a TO into a geometry that fulfils all requirements is complex. To aid in this process, this paper suggest an approach based on combining overhang-constrained TO with lattice-based TO to automate complex tasks, retain parametric control, and to minimize manufacturing cost. The approach is validated through a benchmark part.
When designing high performance sports equipment for Paralympic athletes, there are many unknowns for the design engineer to consider. The design challenge is an optimisation task per individual athlete. However, modelling this optimisation is difficult due to the many variables. This article presents the design of an experiment for identifying and evaluating various seating positions in Paralympic rowing by using a rowing ergometer with a modified seat. Results indicate that changing seating position has a substantial impact on per-athlete rowing performance.
We consider a deformation
of the Dedekind eta function depending on two
-dimensional simple lattices
and two parameters
$(m,t)\in (0,\infty )$
, initially proposed by Terry Gannon. We show that the minimisers of the lattice theta function are the maximisers of
in the space of lattices with fixed density. The proof is based on the study of a lattice generalisation of the logarithm, called the lattice logarithm, also defined by Terry Gannon. We also prove that the natural logarithm is characterised by a variational problem over a class of one-dimensional lattice logarithms.
There is an emerging body of legal thought directed at contemporary profiling and data science. Some of this focuses on limiting ‘human computability’, some addresses questions of ‘manipulation’ and ‘behavioural optimisation’, and some suggests ways to introduce friction into the information environment to interrupt the translation of data into meaning. This chapter looks at how some of these ideas might be implemented as computational legal applications. It argues that the legal subject of algorithmic accountability can be expanded into a rights-bearing entity that can actively contest how it is computationally interpreted, through mechanisms of ‘contestation by design’. The chapter also describes the utility of concepts like ‘context’ for building boundaries and friction into information architectures, not simply in terms of information flow but also for constraining how the design of those architectures influences and structures behaviour. Finally, it suggests the shape of a new ‘composite’ legal person as a mechanism to constrain profiling behavior by producing an identity as an interface to the ‘world state’ it inhabits.
Navigation methods, traditional and modern, use lines of position in the plane. Standard Gaussian assumptions about errors leads to a constant sum of squared distances from the lines defining a probability contour. It is well known these contours are a family of ellipses centred on the most probable position and they can be computed using algebraic methods. In this paper we show how the most probable position, the axes and foci of ellipses can be found using geometric methods. This results in a ruler and compasses construction of these points and this gives insight into the way the shape and orientation of the probability contours depend on the angles between the lines of position. We start with the classical case of three lines of position with equal variances, we show how this can be extended to the case where the variances in the errors in the lines of position differ, and we go on to consider the case of four lines of position using a methodology that generalises to an arbitrary number of lines.
The maximum attainable performance of small gas turbines represents a strong limitation to the operating altitude and endurance of high-altitude unmanned aerial vehicles (UAVs). Significant improvement of the cycle thermal efficiency can be achieved through the introduction of heat exchangers, with the consequent increase of the overall engine weight. Since semi-closed cycle engines can achieve a superior degree of compactness compared to their open cycle counterparts, their use can offset the additional weight of the heat exchangers. This paper applies semi-closed cycles to a high-altitude UAV propulsion system, with the objective of assessing the benefits introduced on the engine performance and weight. A detailed model has been created to account for component performance and size variation as function of thermodynamic parameters. The sizing has been coupled with a multi-objective optimisation algorithm for minimum specific fuel consumption and weight. Results of two different semi-closed cycle configurations are compared with equivalent state-of-the-art open cycles, represented by a recuperated and an intercooled-recuperated engine. The results show that, for a fixed design power output, engine weight is approximately halved compared to state-of-the-art open cycles, with slightly improved specific fuel consumption performance. Optimum semi-closed cycles furthermore operate at higher overall pressure ratios than open cycles and make use of recuperators with higher effectiveness as the mass penalty of the recuperator is smaller due to the lower engine mass flow rates.
The maximisation of control power is considered for an aircraft with multiple control surfaces, with the force and moment coefficients specified by polynomials of the control surface deflections of degree two. The optimal deflections, which maximise and minimise any force or moment coefficient, are determined subject to constraints on the range of deflection of each control surface. The results are applied to a flying wing configuration to determine: (i/ii) the pitch trim, at the lowest drag for the fastest climb, and at the highest drag for the steepest descent; (iii) the maximum and minimum pitching moment; (iv) the maximum and minimum yaw control power and the fraction needed to compensate an outboard engine failure for several propulsion configurations; (v) the maximum and minimum rolling moment. The optimal use of all control surfaces has significant advantages over using just one, e.g. the range of drag modulation with pitch trim is much wider and the maximum and minimum available control moments larger.
Electric Vehicles (EVs) are very quite at low speed, which can be hazardous for pedestrians. It is necessary to add warning sounds but this can represent an annoyance if they are poorly designed. On the other hand, they can be not enough detectable because of the masking effect due to the background noise. In this paper, we propose a method for the design of EV sounds that takes into account in the same time detectability and unpleasantness. It is based on user tests and implements Interactive Genetic Algorithms (IGA) for the optimization of the sounds. Synthesized EV sounds, based on additive synthesis and filtering, are proposed to a set of participants during a hearing test. An experimental protocol is proposed for the assessment of the detectability and the unpleasantness of the EV sounds. After the convergence of the method, sounds obtained with the IGA are compared to different sound design proposals. Results show that the quality of the sounds designed by the IGA method is significantly higher than the design proposals, validating the relevance of the approach.
The Life Cycle Energy Optimisation (LCEO) methodology aims at finding a design solution that uses a minimum amount of cumulative energy demand over the different phases of the vehicle's life cycle, while complying with a set of functional constraints. This effectively balances trade-offs, and therewith avoids sub-optimal shifting between the energy demand for the cradle-to-production of materials, operation of the vehicle, and end-of-life phases. The present work describes the extension of the LCEO methodology to perform holistic product system optimisation. The constrained design of an automotive component and the design of a subset of the processes which are applied to it during its life cycle are simultaneously optimised to achieve a minimal product system life cycle energy. A subset of the processes of the end-of-life phase of a vehicle's roof are modeled through a continuous formulation. The roof is modeled as a sandwich structure with its design variables being the material compositions and the thicknesses of the different layers. The results show the applicability of the LCEO methodology to product system design and the use of penalization to ensure solution feasibility.
In the last few years there has been a noticeable change in the development of headlamp systems in the field of vehicle lighting technology. Starting with adaptive front-lighting systems via Matrix LED systems, high-resolution headlamps will provide more safety in road traffic in the near future.
For the implementation of high-resolution headlamps various spatial light modulators and light generating technologies can be applied. The emitted light of the light source is directed via an illumination optics onto the modulator and a projection optics is applied to image the spatial light modulator into the traffic area. The formerly mechatronic systems are thus increasingly become opto- mechatronic systems. Therefore, the optic design must be taken into account in the early development phase of these systems.
In this paper we present a methodical approach to describe the optic design for optomechatronic systems. This approach can be used to develop efficient and high-intensity optomechatronic systems using various spatial light modulators and light generating technologies. Conclusively we demonstrate an exemplary application of the methodology on a high-resolution projection module.
Shortening product development cycles while improving cost efficiency and quality epitomize a key challenge in today's competitive market environment. Integrated approaches simultaneously taking into account a conceptual design, material and processing definition methodologically facilitate the progress of promising product solutions most effectively. However, assorted approaches in the field of lightweight design as well as material selection mostly trying to cover alternative solutions on a component-specific level exclusively, yet.
Thus, this contribution outlines a cross-component material selection for function-based lightweight design within the Extended Target Weighing Approach covering the identification and evaluation of lightweight design potentials. The developed method is based on Ashby's material selection additionally taking into account project objectives for mass, costs and CO2 emissions in individual functional design spaces. Resulting in material combinations fitting to clearly stated project targets, the product engineer is already supported in an early phase of product development when initially assessing feasible materials for the overall system development.