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Today the energy storage systems are still encumbering, therefore it is useful to think about the optimization of a railgun system in order to achieve the best performance with the lowest energy input. In this paper, an optimal design method considering 5 parameters is proposed to improve the energy conversion efficiency of a simple railgun. In order to avoid costly trials, the field- circuit method is employed to analyze the operations of different structural railguns with different parameters respectively. And the orthogonal test approach is used to guide the simulation for choosing the better parameter combinations, as well reduce the calculation cost. The research shows that the proposed method gives a better result in the energy efficiency of the system. To improve the energy conversion efficiency of electromagnetic rail launchers, the selection of more parameters must be considered in the design stage, such as the width, height and length of rail, the distance between rail pair, and pulse forming inductance. However, the relationship between these parameters and energy conversion efficiency cannot be directly described by one mathematical expression. So optimization methods must be applied to conduct design. In this paper, a rail launcher with five parameters was optimized by using orthogonal test method. According to the arrangement of orthogonal table, the better parameters’ combination can be obtained through less calculation. Under the condition of different parameters’ value, field and circuit simulation analysis were made. The results show that the energy conversion efficiency of the system is increased by 71.9 % after parameters optimization.

A measurement of the production of three isolated photons in proton–proton collisions at a centre-of-mass energy $\sqrt{s}$ = 8 TeV is reported. The results are based on an integrated luminosity of 20.2 fb$^{−1}$ collected with the ATLAS detector at the LHC. The differential cross sections are measured as functions of the transverse energy of each photon, the difference in azimuthal angle and in pseudorapidity between pairs of photons, the invariant mass of pairs of photons, and the invariant mass of the triphoton system. A measurement of the inclusive fiducial cross section is also reported. Next-to-leading-order perturbative QCD predictions are compared to the cross-section measurements. The predictions underestimate the measurement of the inclusive fiducial cross section and the differential measurements at low photon transverse energies and invariant masses. They provide adequate descriptions of the measurements at high values of the photon transverse energies, invariant mass of pairs of photons, and invariant mass of the triphoton system. Physics letters / B 781, 55 - 76 (2018). doi:10.1016/j.physletb.2018.03.057 Published by North-Holland Publ., Amsterdam

In this work, we show a new methodology for automatic supervision and fault detection of PV Systems, based mainly on the analysis of the power losses. This methodology includes parameter extraction techniques to calculate main PV system parameters from monitoring data [1-2], taking into account the real irradiance and module temperature, allowing simulation and evaluation of the PV system behaviour in real time. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4534-4536

Proc. of PANIC 2014, 95 - 98; DESY-PROC-2014-02; ISSN 1435-8077 Contribution to Proceedings

Multi-particle cumulants and corresponding Fourier harmonics are measured for azimuthal angle distributions of charged particles in $pp$ collisions at $\sqrt{s}$ = 5.02 and 13 TeV and in $p$+Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV, and compared to the results obtained for low-multiplicity Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV. These measurements aim to assess the collective nature of particle production. The measurements of multi-particle cumulants confirm the evidence for collective phenomena in $p$+Pb and low-multiplicity Pb+Pb collisions. On the other hand, the $pp$ results for four-particle cumulants do not demonstrate collective behaviour, indicating that they may be biased by contributions from non-flow correlations. A comparison of multi-particle cumulants and derived Fourier harmonics across different collision systems is presented as a function of the charged-particle multiplicity. For a given multiplicity, the measured Fourier harmonics are largest in Pb+Pb, smaller in $p$+Pb and smallest in $pp$ collisions. The $pp$ results show no dependence on the collision energy, nor on the multiplicity. The European physical journal / C 77(6), 428 (2017). doi:10.1140/epjc/s10052-017-4988-1 Published by Springer, Berlin

The fabrication and design of novel materials and devices for advanced photovoltaics, like the intermediate-band solar cell (IBSC), requires the use of specific characterization tools providing information about their optoelectronic properties. We have tested the suitability of photoreflectance for the characterization of IBSC prototypes based on quantum dots and compared the results obtained with those predicted by the theory. Nonidealities in operative devices have been identified and detailed information has been obtained about the electronic structure of the materials. We have compared PR spectra of IBSCs with those obtained from alternative device architectures, namely a triple-junction solar cell and a multi-quantum well structure. Some general conclusions are drawn demonstrating the potential of the technique. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 428-431

The enhancement of the electromagnetic field within the grooves of a metallic diffraction grating is analyzed. A perfect conductor, rectangular-shaped diffraction grating is assumed, therefore, the field enhancement analyzed in this work is due to resonances caused by the structure itself, and not to the so-called surface-plasmon resonances which are observed to be influenced by metal properties as well. The modal approach has been employed for calculations. Basically, the squared amplitude of the electric field within the grooves is calculated as a function of the wavelength of the incident light. Similarly, the behaviour of the structure when exposed to a conical bundle of light is also analyzed. The present results show that a field intensity enhancement of the order of 100 is achievable. However, the spectral width of the resonances decrease with increasing enhancement as is expected. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 404-405