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Abstract The dynamics of isolated-photon plus two-jet production in pp collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset corresponding to an integrated luminosity of 36.1 fb−1. Cross sections are measured as functions of a variety of observables, including angular correlations and invariant masses of the objects in the final state, γ + jet + jet. Measurements are also performed in phase-space regions enriched in each of the two underlying physical mechanisms, namely direct and fragmentation processes. The measurements cover the range of photon (jet) transverse momenta from 150 GeV (100 GeV) to 2 TeV. The tree-level plus parton-shower predictions from Sherpa and Pythia as well as the next-to-leading-order QCD predictions from Sherpa are compared with the measurements. The next-to-leading-order QCD predictions describe the data adequately in shape and normalisation except for regions of phase space such as those with high values of the invariant mass or rapidity separation of the two jets, where the predictions overestimate the data.

Abstract This paper discusses the minimization of the fuel consumption of a gasoline engine through dynamic optimization. The minimization uses a mean value model of the powertrain and vehicle. This model has two state variables: the pressure in the engine intake manifold and the engine speed. The control input is the throttle valve angle. The model is identified on a universal engine dynamometer. Optimal state and control trajectories are calculated using Bock’s direct multiple shooting method, implemented in the software MUSCOD-II. The developed approach is illustrated both in simulation and experimentally for a generic test case where a vehicle accelerates from 1100 rpm to 3700 rpm in 30 s . The optimized trajectories yield minimal fuel consumption. The experiments show that a linear engine speed trajectory yields an extra fuel consumption of 13 % when compared to the optimal trajectory. It is shown that, with a simple model, a significant amount of fuel can be saved without loss of the fun-to-drive.

Abstract This paper focuses on the primary development of novel analytical and numerical studies for the smart plate structure due to the effects of point mass locations, dynamic motions, and network segmentations. Instead of the alternative capabilities in active and passive control systems, the technical application of the present work can also be found in the energy harvesting system. The simplified theoretical studies have shown the simultaneous derivations with full variational parameters. In particular, these parameters consist of the mechanical and electromechanical systems, the mixed series–parallel electrode segment connection, and the harvesting circuit. The mechanical system parameters include elasticity with stress-strain relation, internal damping stress, air damping, and dynamics of the integrated physical system. The electromechanical system parameters include electrical displacement, electrical stress and electric-polarity field of the piezoelectricity. For the analytical approach, the governing equations of motion based on the Gram-Schmidt iterative process have been derived using the extended Hamiltonian principle and Ritz method-based weak form system. For validation, the electromechanical finite element equations reduced from the extended Lagrange’s equations have been developed using electromechanical discretisation and coupling transformation techniques. As a result, the two theoretical models have shown distinct frequency response equations for the dynamic solutions of the integrated physical system. In parametric studies, the two theoretical models of the smart plates with variable geometrical aspect ratio and different locations of point mass are discussed, giving good agreement. The strain mode analysis is utilised to identify the shape patterns at the region of the smart plate due to the change of strains. As a result, it can affect the electric power productions at the frequency domain. At certain cases, the appearance of asymmetric strain mode shapes may occur, resulting in the electric power reductions. To alleviate such condition, the activation of arbitrary electrode segments using the network connection can be implemented. Moreover, the smart structural model with different point mass locations is also subjected to the base excitation and the dynamic force. The proposed technique can adaptively and accumulatively generate the optimal power outputs and shift the resonance frequencies. All results of the parametric studies quantitatively show the dynamic system behaviours.