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Multimetric Evaluation of the Effectiveness of Remote Learning in Mechanical and Industrial Engineering During the COVID19 Pandemic: Indicators and Guidance for Future PreparednessThis data set contains data collected from 5 universities in 5 countries about the effectiveness of elearning during the COVID19 pandemic, specifically tailored to mechanical and industrial engineering students. A survey was administered in May, 2020 at these universities simultaneously, using Google Forms. The survey had 41 questions, including 24 questions on a 5point Likert scale. The survey questions gathered data on their program of study, year of study, university of enrolment and mode of accessing their online learning content. The Likert scale questions on the survey gathered data on the effectiveness of digital delivery tools, student preferences for remote learning and the success of the digital delivery tools during the pandemic. All students enrolled in modules taught by the authors of this study were encouraged to fill the survey up. Additionally, remaining students in the departments associated with the authors were also encouraged to fill up the form through emails sent on mailing lists. The survey was also advertised on external websites such as survey circle and facebook. Crucial insights have been obtained after analysing this data set that link the student demographic profile (gender, program of study, year of study, university) to their preferences for remote learning and effectiveness of digital delivery tools. This data set can be used for further comparative studies and was useful to get a snapshot of student preferences and elearning effectiveness during the COVID19 pandemic, which required the use of elearning tools on a wider scale than previously and using new modes such as video conferencing that were set up within a short timeframe of a few days or weeks.

Multiorder fractional differential equations and their numerical solutionThis article considers the numerical solution of (possibly nonlinear) fractional differential equations of the form y(α)(t)=f(t,y(t),y(β1)(t),y(β2)(t),…,y(βn)(t)) with α>βn>βn−1>>β1 and α−βn1, βj−βj−11, 0

A multispecies chemotaxis system: Lyapunov functionals, duality, critical massWe introduce a multispecies chemotaxis type system admitting an arbitrarily large number of population species, all of which are attracted vs.\ repelled by a single chemical substance. The production vs.\ destruction rates of the chemotactic substance by the species is described by a probability measure. For such a model we investigate the variational structures, in particular we prove the existence of Lyapunov functionals, we establish duality properties as well as a logarithmic HardyLittlewoodSobolev type inequality for the associated free energy. The latter inequality provides the optimal critical value for the conserved total population mass.

Multimodal Shear Wave Deicing Using Fibre Piezoelectric Actuator on Composite for Aircraft WingsThe formation and accretion of ice on aircraft wings during flight can be potentially disastrous and existing inflight deicing methods are either bulky or power consuming. This paper investigates the use of shear wave deicing driven by a macro fibre piezoelectric composite actuator on a composite plate typically used for aircraft wings. While the few existing research on this novel deicing approach focused on either theoretical studies or single frequency mode optimization that required highexcitation amplitudes, this study revealed that the use of multimodal excitation through broadband frequency sweeps has the potential to promote the chance of shear stress induced deicing at a relatively small excitation amplitude. The results reported here form the foundation for a pathway towards low power and lightweight deicing mechanism for inflight aircraft wings.

Multiphysics vibration FE model of piezoelectric macro fibre composite on carbon fibre composite structuresThis paper presents a finite element (FE) model developed using commercial FE software COMSOL to simulate the multiphysical process of pieozoelectric vibration energy harvesting (PVEH), involving the dynamic mechanical and electrical behaviours of piezoelectric macro fibre composite (MFC) on carbon fibre composite structures. The integration of MFC enables energy harvesting, sensing and actuation capabilities, with applications found in aerospace, automotive and renewable energy. There is an existing gap in the literature on modelling the dynamic response of PVEH in relation to realworld vibration data. Most simulations were either semianalytical MATLAB models that are geometry unspecific, or basic FE simulations limited to sinusoidal analysis. However, the use of representative environment vibration data is crucial to predict practical behaviour for industrial development. Piezoelectric device physics involving solid mechanics and electrostatics were combined with electrical circuit defined in this FE model. The structure was dynamically excited by interpolated vibration data files, while orthotropic material properties for MFC and carbon fibre composite were individually defined for accuracy. The simulation results were validated by experiments with <10﹪ deviation, providing confidence for the proposed multiphysical FE model to design and optimise PVEH smart composite structures.

Multiscale Understanding of Electric Polarization in Poly(vinylidene fluoride)Based Ferroelectric PolymersPoly(vinylidene fluoride) (PVDF) and PVDFbased copolymers with trifluoroethylene (PVDFTrFE) have attracted considerable academic and industrial interest due to their ferroelectric properties, which are only presented in very few polymers. However, the underlying fundamentals of molecular ordering and induced polarizations are complex and not fully understood. Herein, PVDF, PVDFTrFE and their blends, prepared using melt extrusion and hot pressing, have been selected to obtain controlled case studies with welldefined chain ordering and microstructures. Impedance analysis and terahertz timedomain spectroscopy are exploited to investigate electric polarization in PVDFbased polymers at different length scales. The extruded ferroelectric films show inplane chain orientation and higher domain wall density compared to hot pressed films with randomlydistributed polymer chains, which favors the polarization at low frequencies (Hz to MHz), as concluded from the higher dielectric constants and more prominent high electric field polarization switching features. However, the domain walls cannot respond at high frequencies, which leads to lower dielectric constants in the extruded films at THz frequencies.

Nanodiamond based surface modified screenprinted electrodes for the simultaneous voltammetric determination of dopamine and uric acid.The electroanalytical detection of the neurotransmitter dopamine (DA) in the presence of uric acid (UA) is explored for the first time using commercially procured nanodiamonds (NDs). These are electrically wired via surface modification upon screenprinted graphite macroelectrodes (SPEs). The surface coverage of the NDs on the SPEs was explored in order to optimize electroanalytical outputs to result in wellresolved signals and in low limits of detection. The (electro)analytical outputs are observed to be more sensitive than those achieved at bare (unmodified) SPEs. Such responses, previously reported in the academic literature have been reported to be electrocatalytic and have been previously attributed to the presence of surface sp2 carbon and oxygenated species on the surface of the NDs. However, XPS analysis reveals the commercial NDs to be solely composed of nonconductive sp3 carbon. The low/negligible electroconductivity of the NDs was further confirmed when ND paste electrodes were fabricated and found to exhibit no electrochemical activity. The electroanalytical enhancement, when using NDs electronically wired upon SPEs, is attributed not to the NDs themselves being electrocatalytic, as reported previously, but rather changes in mass transport where the inert NDs block the underlying electroactive SPEs and create a random array of graphite microelectrodes. The electrode was applied to simultaneous sensing of DA and UA at pH 5.5. Figures of merit include (a) low working potentials of around 0.27 and 0.35 V (vs. Ag/AgCl); and (b) detection limits of 5.7 × 107 and 8.9 × 107 M for DA and UA, respectively. Graphical abstract The electroanalytical enhancement of screenprinted electrodes modified with inert/nonconductive nanodiamonds is due to a change in mass transfer where the inert nanodiamonds facilitate the production of a random microelectrode array.

Neutral delay differential equations in the modelling of cell growthIn this contribution, we indicate (and illustrate by example) roles that may be played by neutral delay differential equations in modelling of certain cell growth phenomena that display a time lag in reacting to events. We explore, in this connection, questions involving the sensitivity analysis of models and related mathematical theory; we provide some associated numerical results.

New binary selfdual codes of lengths 56, 58, 64, 80 and 92 from a modification of the four circulant construction.In this work, we give a new technique for constructing selfdual codes over commutative Frobenius rings using $\lambda$circulant matrices. The new construction was derived as a modification of the wellknown four circulant construction of selfdual codes. Applying this technique together with the buildingup construction, we construct singlyeven binary selfdual codes of lengths 56, 58, 64, 80 and 92 that were not known in the literature before. Singlyeven selfdual codes of length 80 with $\beta \in \{2,4,5,6,8\}$ in their weight enumerators are constructed for the first time in the literature.

New binary selfdual codes via a generalization of the four circulant constructionIn this work, we generalize the four circulant construction for selfdual codes. By applying the constructions over the alphabets $\mathbb{F}_2$, $\mathbb{F}_2+u\mathbb{F}_2$, $\mathbb{F}_4+u\mathbb{F}_4$, we were able to obtain extremal binary selfdual codes of lengths 40, 64 including new extremal binary selfdual codes of length 68. More precisely, 43 new extremal binary selfdual codes of length 68, with rare new parameters have been constructed.

A New Electrode Design Method in Piezoelectric Vibration Energy Harvesters to Maximize Output PowerA resonant vibration energy harvester typically comprises of a clamped anchor and a vibrating shuttle with a proof mass. Piezoelectric materials are embedded in locations of high strain in order to transduce mechanical deformation into electrical charge. Conventional design for piezoelectric vibration energy harvesters (PVEH) usually utilizes piezoelectric materials and metal electrode layers covering the entire surface area of the cantilever with no consideration provided to examine the tradeoff involved with respect to maximize output power. This paper reports on the theory and experimental verification underpinning optimization of the active electrode area in order to maximize output power. The calculations show that, in order to maximize the output power of a PVEH, the electrode should cover the piezoelectric layer from the peak strain area to a position, where the strain is a half of the average strain in all the previously covered area. With the proposed electrode design, the output power can be improved by 145% and 126% for a cantilever and a clampedclamped beam, respectively. MEMS piezoelectric harvesters are fabricated to experimentally validate the theory.

New Extremal Binary Selfdual Codes from block circulant matrices and block quadratic residue circulant matricesIn this paper, we construct selfdual codes from a construction that involves both block circulant matrices and block quadratic residue circulant matrices. We provide conditions when this construction can yield selfdual codes. We construct selfdual codes of various lengths over F2 and F2 + uF2. Using extensions, neighbours and sequences of neighbours, we construct many new selfdual codes. In particular, we construct one new selfdual code of length 66 and 51 new selfdual codes of length 68.

New Extremal binary selfdual codes of length 68 from generalized neighborsIn this work, we use the concept of distance between selfdual codes, which generalizes the concept of a neighbor for selfdual codes. Using the $k$neighbors, we are able to construct extremal binary selfdual codes of length 68 with new weight enumerators. We construct 143 extremal binary selfdual codes of length 68 with new weight enumerators including 42 codes with $\gamma=8$ in their $W_{68,2}$ and 40 with $\gamma=9$ in their $W_{68,2}$. These examples are the first in the literature for these $\gamma$ values. This completes the theoretical list of possible values for $\gamma$ in $W_{68,2}$.

New Extremal SelfDual Binary Codes of Length 68 via Composite Construction, F2 + uF2 Lifts, Extensions and NeighborsWe describe a composite construction from group rings where the groups have orders 16 and 8. This construction is then applied to find the extremal binary selfdual codes with parameters [32, 16, 8] or [32, 16, 6]. We also extend this composite construction by expanding the search field which enables us to find more extremal binary selfdual codes with the above parameters and with different orders of automorphism groups. These codes are then lifted to F2 + uF2, to obtain extremal binary images of codes of length 64. Finally, we use the extension method and neighbor construction to obtain new extremal binary selfdual codes of length 68. As a result, we obtain 28 new codes of length 68 which were not known in the literature before.

New QuinolineBased Heterocycles as Anticancer Agents Targeting Bcl2The Bcl2 protein has been studied as an anticancer drug target in recent years, due to its gatekeeper role in resisting programmed cancer cell death (apoptosis), and the design of BH3 domain mimetics has led to the clinical approval of Venetoclax (ABT199) for the treatment of chronic lymphocytic leukaemia. In this work we extend our previous studies on the discovery of indolebased heterocycles as Bcl2 inhibitors, to the identification of quinolin4yl based oxadiazole and triazole analogues. Target compounds were readily synthesized via a common arylsubstituted quinolin4carbonylNarylhydrazine1carbothioamide (5a⁻b) intermediate, through simple variation of the basic cyclisation conditions. Some of the quinolinebased oxadiazole analogues (e.g. compound 6i) were found to exhibit submicromolar antiproliferative activity in Bcl2expressing cancer cell lines, and submicromolar IC50 activity within a Bcl2Bim peptide ELISA assay. The Bcl2 targeted anticancer activity of 6i was further rationalised via computational molecular modelling, offering possibilities to extend this work into the design of further potent and selective Bcl2 inhibitory heteroaromatics with therapeutic potential.

New SelfDual and Formally SelfDual Codes from Group Ring ConstructionsIn this work, we study construction methods for selfdual and formally selfdual codes from group rings, arising from the cyclic group, the dihedral group, the dicyclic group and the semidihedral group. Using these constructions over the rings $_F2 +uF_2$ and $F_4 + uF_4$, we obtain 9 new extremal binary selfdual codes of length 68 and 25 even formally selfdual codes with parameters [72,36,14].

New Selfdual Codes from 2 x 2 block circulant matrices, Group Rings and Neighbours of NeighboursIn this paper, we construct new selfdual codes from a construction that involves a unique combination; $2 \times 2$ block circulant matrices, group rings and a reverse circulant matrix. There are certain conditions, specified in this paper, where this new construction yields selfdual codes. The theory is supported by the construction of selfdual codes over the rings $\FF_2$, $\FF_2+u\FF_2$ and $\FF_4+u\FF_4$. Using extensions and neighbours of codes, we construct $32$ new selfdual codes of length $68$. We construct 48 new best known singlyeven selfdual codes of length 96.

New SelfDual Codes of Length 68 from a 2 × 2 Block Matrix Construction and Group RingsMany generator matrices for constructing extremal binary selfdual codes of different lengths have the form G = (In  A); where In is the n x n identity matrix and A is the n x n matrix fully determined by the first row. In this work, we define a generator matrix in which A is a block matrix, where the blocks come from group rings and also, A is not fully determined by the elements appearing in the first row. By applying our construction over F2 +uF2 and by employing the extension method for codes, we were able to construct new extremal binary selfdual codes of length 68. Additionally, by employing a generalised neighbour method to the codes obtained, we were able to con struct many new binary selfdual [68,34,12]codes with the rare parameters $\gamma = 7$; $8$ and $9$ in $W_{68,2}$: In particular, we find 92 new binary selfdual [68,34,12]codes.

A new visualisation and measurement technology for water continuous multiphase flowsThis paper reports the performance of a research prototype of a new multiphase flow instrument to noninvasively measure the phase flow rates, with the capability to rapidly image the flow distributions of two and threephase (gas and/or oil in water) flows. The research prototype is based on the novel concepts of combining vector Electrical Impedance Tomography (EIT) sensor (for measuring dispersedphase velocity and fraction) with an electromagnetic flow metre (EMF, for measuring continuousphase velocity with the EIT input) and a gradiomanometer flowmixture density metre (FDM), in addition to online water conductivity, temperature and absolute pressure measurements. EIT–EMF–FDM data fusion embedded in the research prototype, including online calibration/compensation of conductivity change due to the change of fluids' temperature or ionic concentration, enables the determination of mean concentration, mean velocity and hence the mean flow rate of each individual phase based on the measurement of dispersedphase distributions and velocity profiles. Results from first flowloop experiments conducted at Schlumberger Gould Research (SGR) will be described. The performance of the research prototype in flowrate measurements are evaluated by comparison with the flowloop references. The results indicate that optimum performance of the research prototype for threephase flows is confined within the measuring envelope 45–100% WaterinLiquid Ratio (WLR) and 0–45% Gas Volume Fraction (GVF). Within the scope of this joint research project funded by the UK Engineering & Physical Sciences Research Council (EPSRC), only vertical flows with a conductive continuous liquid phase will be addressed.

Next Generation Additive Manufacturing: Tailorable Graphene/Polylactic(acid) Filaments Allow the Fabrication of 3D Printable Porous Anodes for Utilisation within LithiumIon BatteriesHerein, we report the fabrication and application of Liion anodes for utilisation within Liion batteries, which are fabricated via additive manufacturing/3D printing (fused depo sition modelling) using a bespoke graphene/polylactic acid (PLA) filament, where the graphene content can be readily tailored and controlled over the range 1–40 wt. %. We demon strate that a graphene content of 20 wt. % exhibits sufficient conductivity and critically, effective 3D printability for the rapid manufacturing of 3D printed freestanding anodes (3DAs); simplifying the components of the Liion battery negating the need for a copper current collector. The 3DAs are physicochemcally and electrochemically characterised and possess sufficient conductivity for electrochemical studies. Critically, it is found that if the 3DAs are used in Liion batteries the specific capacity is very poor but can be significantly improved through the use of a chemical pretreatment. Such treatment induces an increased porosity, which results in a 200fold increase (after anode stabilisation) of the specific capacity (ca. 500 mAhg1 at a current density of 40 mAg1). This work significantly enhances the field of additive manufacturing/3D printed graphene based energy storage devices demonstrating that useful 3D printable batteries can be realised