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This paper presents a robust optimization method to design patch antennas that consider uncertainties from the substrate electromagnetic properties and the manufacturing equipment. The robust optimization method is proposed to design an antenna that uses FR-4 as a substrate, addressing the uncertainties originated from the lack of standardization of this material properties and errors in the manufacturing process of the antenna. By addressing these uncertainties, robust design can result in a low-cost antenna with good performance that is less sensitive to deviations in the defined project variables. The optimization scheme used in this paper is based on NSGA-II, and the robustness of its solutions is quantified with the standard deviation of samples from the performance parameters in the uncertainty set from the design parameters. Two prototypes of patch antennas, one with linear and the other with circular polarization are designed, built, and measured. [ABSTRACT FROM AUTHOR]

This paper presents an evaluation of the influence of aircraft configuration on the boarding and deboarding times using a simplified model and computer simulation. Boarding and deboarding times are important to airlines since both procedures are part of the critical path of the turnaround time (TAT) of aircraft in airports. During the TAT, a series of activities are performed in the aircraft in order to prepare it for the next flight. A reduction in boarding and deboarding times may represent a reduction in TAT for airlines. For the comparisons, three aircraft configurations are used: single aisle 3 × 3 ("six abreast"), single aisle 3 × 2 ("five abreast"), and single aisle 2 × 2 ("four abreast"), all with the same number of passengers. For the boarding analyses, two boarding procedures are used: random and random outside-in. The 2 × 2 aircraft interior configuration holds the shortest boarding times; deboarding times are similar for the three configurations. Also, a sensitivity analysis is carried out, and the results show that the higher the aircraft occupancy and the number of passengers with carry-on baggage, the higher are boarding and deboarding times, with the 2 × 2 having the lowest times in comparison with the other two configurations. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a systematic methodology to aid design a low-cost patch antenna for RFID readers. The geometric antenna parameters are found using multiobjective optimization for return loss minimization and gain maximization. To assess the use of low-cost FR-4 substrate the radiation efficiency has been investigated using software simulations. A prototype antenna was built and its parameters were measured in the anechoic chamber. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:905-908, 2016 [ABSTRACT FROM AUTHOR]

This paper describes a meshless approach to obtain solutions for propagating microwave problems. The Meshless Local Petrov-Galerkin (MLPG) method is used, based on a local weak form tested with the Heaviside step function. The field is approximated by the Point Interpolation method using radial basis function with additional polynomial basis (RPIMp). TEAM workshop problem 18 is solved and its solution is compared with references from the literature. The results are in good agreement, showing that MLPG can be used as a good alternative to finite elements for this kind of problems. [ABSTRACT FROM PUBLISHER]

This paper presents a methodology based on multiobjective evolutionary optimization and a phase control scheme to design a microwave heating applicator for water sterilization. The optimization problem is formulated in terms of two objective functions: one to maximize the amount of water and the other to minimize the energy spent. The device is modeled as a lossy dielectric multilayer irradiated by two microwave sources. The phase control is done by allowing one of the sources to move. By applying the developed methodology, an efficient applicator is obtained. [ABSTRACT FROM PUBLISHER]

This paper describes an approach to solve the thermal-electromagnetic problem inside a single mode applicator loaded with a ceramic sample. The FEM is combined with analytical techniques to solve the electromagnetic problem. We obtain a fast, simple and accurate method that allows performance investigation of the single mode cavity during the whole heating process. A key feature of the method is to permit iris aperture and short position to vary during the heating. The dependence upon temperature of the complex permittivity of the load is included in the model. The simulation of a thin cylinder ceramic shows that the approach proposed is capable to provide accurate results with low computational cost. [ABSTRACT FROM AUTHOR]

We propose a Multiobjective Clonal Selection Algorithm (MCSA) with dynamic variation of its main parameters for the solution of engineering design problems. The MCSA performs a cloning process using different probability distributions, in which the mutation strengths are guided based on a logarithmic rule and on information implicitly created by a simple differential evolution technique. This feature results in a self-adapting search in the algorithm. The efficiency of the MCSA is studied comparing its performance with the Nondominated Sorting Genetic Algorithm II (NSGA-II) in analytical test problems and also in the design of a microwave heating device. The MCSA has outperformed the NSGA-II in all problems investigated. [ABSTRACT FROM AUTHOR]

This letter introduces a novel method for fault location in alternate current transmission lines where neither the line parameters nor terminals synchronization is needed. As opposed to the previous works, it introduces a closed-form solution instead of iterative methods. The results are presented for simulated and real-world problems, indicating that the proposed algorithm attains good performance in the tested cases. [ABSTRACT FROM PUBLISHER]

This paper introduces a novel method for fault location in alternate current transmission lines relying on the voltage and current measurements in both line ends. The novelty of this method lies in the fact that there is no need for terminal synchronization and it can be applied to general untransposed transmission lines. The proposed formulation only applies a closed-form solution; thus, no iterative algorithm is required. Several simulated and real-world results are presented, and they show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]