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In the present paper, we consider the 'bulky knots' and 'bulky links' that appear after cutting of generalized Möbius-Listing GML bodies (with corresponding radial cross sections square) along different generalized Möbius-Listing surfaces GML situated in it. The aim of this article is to examine the number and geometric structure of independent objects that appear after such a cutting process of GML bodies. In most cases, we are able to count the indices of the resulting mathematical objects according to the known tabulation for knots and links of small complexity. [ABSTRACT FROM AUTHOR]

A novel finite-difference time-domain (FDTD) scheme modeling the electromagnetic pulse propagation in Havriliak–Negami dispersive media is proposed. In traditional FDTD methods, the main drawback occurring in the evaluation of the electromagnetic propagation is the approximation of the fractional derivatives appearing in the Havriliak–Negami model equation. In order to overcome this problem, we have developed a novel FDTD scheme based on the direct solution of the time-domain Maxwell equations by using the Riemann–Liouville operator for fractional differentiation. The scheme can be easily applied to other dispersive material models such as Debye, Cole–Cole and Cole–Davidson. Different examples relevant to plane wave propagation in a variety of dispersive media are analyzed. The numerical results obtained by means of the proposed FDTD scheme are found to be in good accordance with those obtained implementing analytical method based on Fourier transformation over a wide frequency range. Moreover, the feasibility of the proposed method is demonstrated by simulating the transient wave propagation in slabs of dispersive materials. [ABSTRACT FROM AUTHOR]

Abstract: A semi-analytical methodology is presented for the accurate analysis of time-domain radiation characteristics of antenna sensors. A locally conformal finite-difference time-domain technique is adopted to derive a minimal pole/residue spherical harmonic expansion of the equivalent currents excited on a suitable Huygens surface enclosing the sensing device. In this way, by using the singularity expansion method, the time-domain gain and effective height of the structure can be evaluated analytically, in terms of the newly introduced incomplete spherical Bessel functions, as the superposition of non-uniform spherical wave contributions attenuating along with the time and space according to the complex poles accounting for the natural resonant processes occurring in the device. The accuracy of the developed technique is assessed by application to an ultrawideband bow-tie antenna-based sensor for millimeter-wave radar measurements. [Copyright &y& Elsevier]

Abstract: The internal and external Robin problems for the Laplace equation in bounded starlike domains are addressed. We show how to derive the relevant solutions by using a suitable Fourier series-like method. Numerical results are specifically obtained considering three-dimensional domains whose boundary is defined by a generalization of the so-called “superformula” introduced by Gielis. By using the computer algebra code Mathematica©, truncated series approximations of the solutions are determined. Our findings are in good agreement with the theoretical results on the Fourier series due to Carleson. [Copyright &y& Elsevier]

The design and full-wave analysis of radio direction finders (RDFs) for ultra-wideband direction-of-arrival estimation is addressed. Conformal elliptically shaped dipoles are selected as antenna sensors by virtue of their good input impedance matching property, performance robustness and conformability. In order to achieve a full angular scanning coverage in the azimuthal direction, a uniform circular direction finding array topology is adopted. The parasitic coupling between the array elements is analysed rigorously, and a dedicated calibration method is used to compensate for non-idealities of the system. In particular, a computationally efficient design procedure for radio direction finding structures is proposed. This procedure, based on a suitable iterative approach, can be usefully adopted to determine the optimal array geometry in terms of number of antenna sensors and volume occupation, while providing a good insight into the physical limitations of the system. By using the developed optimisation technique, a novel RDF operating in the frequency range between 250 MHz and 3.3 GHz is designed, and the relevant performance is thoroughly investigated in realistic operative scenarios. It has been found that the proposed system is rank-1 ambiguity-free, and can be used for tracking both narrow and wideband radio signals. [ABSTRACT FROM AUTHOR]

A compact wideband planar-printed antenna for wireless communications is presented. A suitable shape of the antenna arms and a proper tapering of the feeding line are employed to achieve an impedance bandwidth of more than 10 GHz useful to meet the requirements of several wireless communication standards. An enhanced locally conformal finite-difference time-domain (FDTD) numerical procedure, based on a suitable normalization of the electromagnetic field-related quantities together with a near-to-far-field transformation, is developed to perform the full-wave analysis of the radiating structure. The proposed numerical procedure allows the accurate evaluation of the electromagnetic field distribution from the FDTD domain up to the far-field region, achieving a reduced computational burden compared with conventional FDTD formulations. Using the proposed technique, the electromagnetic and circuital behaviour of the antenna is then derived and analyzed in detail. Numerical results concerning the antenna parameters are in good agreement with experimental measurements. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Antenna modelling approaches, based on suitable spherical harmonic expansions of the radiated electromagnetic field, are addressed and thoroughly investigated. Particular emphasis is put on the simultaneous transverse resonance diffraction (STRD) technique for plasmonic antennas. This method efficiently allows evaluation of the near-field distribution because of the interaction of optical sources, such as surface plasmon waves, with perfectly conducting wedges. The STRD technique based on the multipole expansion of Green's function (MEG) is particularly suitable for the design and rigorous analysis of wireless nano-systems. On the other hand, the characterisation of electromagnetic radiation processes in millimetric/micrometric short-pulse electrical antennas can be conveniently carried out by means of the dedicated singularity-expansion-method(SEM)-based methodology detailed in the second part of this study. Together, the proposed new analytical approaches provide a powerful and complete tool for small antenna design GHz and THz frequency ranges. [ABSTRACT FROM AUTHOR]

Abstract: The interior and exterior Neumann problems for the Helmholtz equation in starlike planar domains are addressed by using a suitable Fourier-like technique. Attention is in particular focused on normal-polar domains whose boundaries are defined by the so called “superformula” introduced by Gielis. A dedicated numerical procedure based on a computer algebra system is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to classical ones, are obtained. Computed results are found to be in good agreement with theoretical findings on Fourier series expansion presented by Carleson. [Copyright &y& Elsevier]

The electromagnetic analysis of a special class of 3D dielectric lens antennas is described in detail. This new class of lens antennas has a geometrical shape defined by the three-dimensional extension of Gielis’ formula. The analytical description of the lens shape allows the development of a dedicated semianalytical hybrid modeling approach based on geometrical tube tracing and physical optic. In order to increase the accuracy of the model, the multiple reflections occurring within the lens are also taken into account. [ABSTRACT FROM AUTHOR]

The MicroBooNE liquid argon time projection chamber located at Fermilab is a neutrino experiment dedicated to the study of short-baseline oscillations, the measurements of neutrino cross sections in liquid argon, and to the research and development of this novel detector technology. Accurate and precise measurements of calorimetry are essential to the event reconstruction and are achieved by leveraging the TPC to measure deposited energy per unit length along the particle trajectory, with mm resolution. We describe the non-uniform calorimetric reconstruction performance in the detector, showing dependence on the angle of the particle trajectory. Such non-uniform reconstruction directly affects the performance of the particle identification algorithms which infer particle type from calorimetric measurements. This work presents a new particle identification method which accounts for and effectively addresses such non-uniformity. The newly developed method shows improved performance compared to previous algorithms, illustrated by a 93.7% proton selection efficiency and a 10% muon mis-identification rate, with a fairly loose selection of tracks performed on beam data. The performance is further demonstrated by identifying exclusive final states in νμCC interactions. While developed using MicroBooNE data and simulation, this method is easily applicable to future LArTPC experiments, such as SBND, ICARUS, and DUNE. [ABSTRACT FROM AUTHOR]

Subterranean waters are often polluted by industrial and anthropic effluents that are drained in subsoil. To prevent and control pollution, legislations of different developed countries require an online monitoring measurement, especially for detecting organic solvents (chlorinated and unchlorinated ones). Online measurements include both real-time and no real-time measurements. In general, it is difficult to implement real-time measurements in stricto sensu for online acquisitions on aqueous effluents since they need to be processed by a modeling. This research presents an experimental measurement system based on infrared (IR) spectroscopy for aqueous effluents containing hydrocarbons and capable of displaying excellent values of pollutant concentrations even in instable conditions; the system is able to detect pollutants either in laminar or turbulent flow. The results show the possibility of avoiding the use of 'Pitot tube' that is employed to create a stagnation point in order to convert kinetic energy into potential one. This conversion allows the transformation of a turbulent flow in a laminar flow making easy measurement of pollutants included in an aqueous effluent. Obviously, 'Pitot tube' is also used for other fluid effluents. The obtained results have been compared with those produced by means of sophisticated IR instrumentation for laboratory applications. [ABSTRACT FROM AUTHOR]

Cosmic ray (CR) interactions can be a challenging source of background for neutrino oscillation and cross-section measurements in surface detectors. We present methods for CR rejection in measurements of charged-current quasielastic-like (CCQE-like) neutrino interactions, with a muon and a proton in the final state, measured using liquid argon time projection chambers (LArTPCs). Using a sample of cosmic data collected with the MicroBooNE detector, mixed with simulated neutrino scattering events, a set of event selection criteria is developed that produces an event sample with minimal contribution from CR background. Depending on the selection criteria used a purity between 50 and 80% can be achieved with a signal selection efficiency between 50 and 25%, with higher purity coming at the expense of lower efficiency. While using a specific dataset and selection criteria values optimized for the MicroBooNE detector, the concepts presented here are generic and can be adapted for various studies of exclusive ν μ CCQE interactions in LArTPCs. [ABSTRACT FROM AUTHOR]

We measure a large set of observables in inclusive charged current muon neutrino scattering on argon with the MicroBooNE liquid argon time projection chamber operating at Fermilab. We evaluate three neutrino interaction models based on the widely used GENIE event generator using these observables. The measurement uses a data set consisting of neutrino interactions with a final state muon candidate fully contained within the MicroBooNE detector. These data were collected in 2016 with the Fermilab Booster Neutrino Beam, which has an average neutrino energy of 800 MeV , using an exposure corresponding to 5.0 × 10 19 protons-on-target. The analysis employs fully automatic event selection and charged particle track reconstruction and uses a data-driven technique to separate neutrino interactions from cosmic ray background events. We find that GENIE models consistently describe the shapes of a large number of kinematic distributions for fixed observed multiplicity. [ABSTRACT FROM AUTHOR]

The development and operation of liquid-argon time-projection chambers for neutrino physics has created a need for new approaches to pattern recognition in order to fully exploit the imaging capabilities offered by this technology. Whereas the human brain can excel at identifying features in the recorded events, it is a significant challenge to develop an automated, algorithmic solution. The Pandora Software Development Kit provides functionality to aid the design and implementation of pattern-recognition algorithms. It promotes the use of a multi-algorithm approach to pattern recognition, in which individual algorithms each address a specific task in a particular topology. Many tens of algorithms then carefully build up a picture of the event and, together, provide a robust automated pattern-recognition solution. This paper describes details of the chain of over one hundred Pandora algorithms and tools used to reconstruct cosmic-ray muon and neutrino events in the MicroBooNE detector. Metrics that assess the current pattern-recognition performance are presented for simulated MicroBooNE events, using a selection of final-state event topologies. [ABSTRACT FROM AUTHOR]