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Water level monitoring and forecasting are essential tasks in flood emergency response. This study proposes an Edge COMputing-based Sensory NETwork (ECOMSNet), an innovative decentralized early warning system (EWS), for water level monitoring and prediction. A sensor-embedded algorithm integrates the direct step method (DSM) with a microgenetic algorithm (MGA). This algorithm predicts the water surface profile and corrects it once water level observations are available. It also meets efficiency requirements to accommodate sensor computation limitations. The errors in the predicted water surface profiles in channels with gradually varied flows are 5% in a laboratory flume experiment and below 10% in a field experiment. The ECOMSNet is an achievement of edge computing-based Internet of Things. It shows potential to increase emergency response efficiency. However, the system requires further refinement and testing if it is to adequately address rapidly varied unsteady flow in a scaled-up implementation.

In this paper, an innovative adaptive directional overcurrent protection system for electric power distribution systems with respect to distributed generation is proposed. The proposed system supervises network topology based on the monitoring functionality of numerical relays. The system detects any changes in the configuration and recalculates the directional overcurrent protection settings by using a microgenetic algorithm. The proposed system was evaluated for several operating scenarios and insertion levels of distributed generation, and then compared with both conventional and adaptive protection systems by means of a traditional genetic algorithm. The results showed that the performance of the proposed system is superior to the other two methods in terms of both speed and selectivity. This shows that this is a promising proposal for the protection of modern electric power distribution systems.

This paper presents parameter and topology optimization of inductor shapes using evolutionary algorithms. The goal of the optimization is to reduce the size of inductors satisfying the specifications on inductance values under weak and strong bias-current conditions. The inductance values are computed from the finite-element (FE) method taking magnetic saturation into account. The result of the parameter optimization, which leads to significant reduction in the volume, is realized for test, and the dependence of inductance on bias currents is experimentally measured, which is shown to agree well with the computed values. Moreover, novel methods are introduced for topology optimization to obtain inductor shapes with homogeneous ferrite cores suitable for mass production.

In this article, a printed U-type ultra wide-band (UWB) antenna is designed for UWB communication using a microgenetic algorithm (MGA) in conjunction with the finite-difference time-domain (FDTD) method. A stepped microstrip configuration which improves the impedance bandwidth is optimized by using MGA and FDTD to achieve the UWB characteristics. The measured VSWR of the antenna is less than 2 from 3.1 GHz to 10.6 GHz. The proposed antenna has a good radiation characteristic by measurement and the simulated gain is between 3.3 and 6 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1289–1292, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23358

The performance of a binary-coded microgenetic algorithm (GA) applied to planar near-field antenna characterization is analyzed in this paper. The method replaces the antenna with an equivalent model consisting of short dipoles, whose optimization is carried out using different GA strategies. Results of reconstructed far-field patterns from synthetic near-field data and a detailed analysis of the GA-based approach are included. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 422–426, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11237

This paper presents a new formulation for placement of switches in distribution of electric power. An approach for determination of the location of tie switches and section switches using a multi-objective microgenetic algorithm is proposed. In the procedure, load importance, reliability index, remote or manual controlled switch and investments costs are considered. The results are based on simulations in a 69-bus test system presented and the results are compared to the solution given by others search techniques. This comparison confirms the efficiency of the proposed method which makes it promising to solve complex problems of tie switches and section switches placement in distribution feeders.

This article presents a novel methodology for designing double-ridged waveguides by numerically optimizing their geometric shape such that they sustain the two prescribed lowest order modes. The field solution to the problem is obtained by using the finite element method. The performance of the microgenetic algorithm and the quasi-Newton methods is studied for carrying out geometry optimization. This generalized formulation is capable of handling inhomogeneous material fillings in the guide, and computational results are presented to demonstrate the versatility of the proposed technique. © 2002 Wiley Periodicals, Inc. Int J RF and Microwave CAE 12, 530–539, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mmce.10053

In this paper, we present the experimental results of microwave absorbers with a frequency-selective surface (FSS) embedded in an impedance-graded carbon fiber (CF) composite. Samples with different FSS patterns embedded in CF composites are fabricated, and experiments are carried out to find the effects of embedded FSSs. It is found that both the FSS pattern and its location in the composite are critical for the reflection property of the sample. The results are compared with the theoretical predictions using the microgenetic algorithm (MGA), and are in good agreement. © 2002 John Wiley & Sons, Inc. Microwave Opt Technol Lett 32: 245–249, 2002.

Transients in pressurized polymeric pipes are analyzed by means of a two-dimensional (2D) Kelvin-Voigt viscoelastic model, calibrated by means of a microgenetic algorithm on the basis of pressure traces. The reliability of the proposed model is then tested by comparing numerical and experimental profiles of the axial component of the local velocity, the latter measured by means of an ultrasonic Doppler velocimeter. Differences between transients in viscoelastic and elastic pipes are pointed out by considering a 2D model in which an elastic behavior is assumed for pipe material. The comparison between the two 2D models allows attribution of the faster decay of pressure oscillations and velocity profiles to viscoelasticity because of the time-shift between pressure oscillation and retarded circumferential strain. The 2D analysis shows that the viscoelastic model generally presents flatter velocity profiles with respect to the elastic model.

A new approach for solving the Schrodinger equation based on a microgenetic algorithm ( μ -GA) is presented. Feed forward neural network is used to represent the solution, while random point evaluation method (RPEM) is introduced to define the fitness score to be maximized in the μ -GA breeding procedure. Convergence of the final stage of searching is accelerated by invoking the deterministic optimizer. The algorithm is tested in the calculation of one-dimensional harmonic oscillator and double-well potential systems.

High quality ab initio calculations for the interaction of He with the B 3Π0u+ state of Cl2 for three r(Cl–Cl) distances, and for the He(1S)+Cl(2P) interaction are used to obtain a three-dimensional potential energy surface for the system. The surface was used to calculate HeCl2 excitation spectra, predissociation lifetimes, and product state distributions for comparison with experimental data, and yields a remarkably good agreement. The largest discrepancy is in the dependence of the lifetime on the excited state vibrational level. The calculated lifetimes are too short for the lowest measured vibrational levels. To investigate how the surface could be modified to obtain even better agreement, a microgenetic algorithm was used to adjust the potential parameters to improve the fit. The adjusted surface has a softer repulsive wall for small Cl–Cl separations which helps to lengthen the excited state lifetimes and yields better agreement with the data. Also, the shape of the well region is adjusted somewhat...

We propose the hybrid integration of an air hole photonic crystal (PhC) structure with a high /spl Delta/ (0.75%) single-mode silica waveguide to achieve an ultracompact high efficiency 90/spl deg/ bend for transverse-magnetic polarized light. Diffraction from the periodic boundary between the PhC and silica waveguide regions is shown to seriously degrade the optical efficiency of the bend. A microgenetic algorithm (/spl mu/GA) combined with a two-dimensional finite-difference time-domain method is used to modify the PhC and its boundary layer to suppress this diffraction which in turn maximizes bend efficiency. The final optimized structure has a 99.4% bend efficiency at a wavelength of 1.55 /spl mu/m and occupies an area of only 27 /spl times/ 27 /spl mu/m.

U ovom radu istražena je mogućnost primjene genetičkog algoritma za rješavanje optimizacijskih problema u realnom vremenu. Proveden je veliki broj numeričkih eksperimenata temeljem kojih je utvrđen utjecaj pojedinih parametara na ponašanje GA s ciljem utvrđivanja optimalnih parametara algoritma. U ovom radu predstavljena je metoda određivanja optimalnih parametara mikrogenetičkog algoritma temeljem poznatih optimalnih parametara genetičkog algoritma. Provedena je analiza ponašanja mikrogenetičkog algoritma pomoću Markovljevih lanaca. Temeljem te analize razvijen je operator kontrakcije prostora rješenja koji povećava točnost rješenja genetičkog algoritma. Opisani algoritam primijenjen je za rješavanje problema inverzne kinematike hiperredundantnog robota. Problem inverzne kinematike definiran je kao optimizacijski problem i definiran je vektorski oblik kromosoma pa su i genetički operatori prilagođeni vektorskom obliku kromosoma. Vektorski oblik genetičkog algoritma primijenjen je i za vremensku optimizaciju CAN sabirnice kojom se smanjuje vrijeme kašnjenja poruka kod većih opterećenja sabirnice. Mikrogenetički algoritam za rješavanje problema inverzne kinematike implementiran je na nekoliko računalnih platformi, dok je genetički algoritam za analizu CAN sabirnice testiran na postojećem upravljačkom sustavu vatrogasnog vozila. This paper analyses the possibility of using genetic algorithms to solve real time optimization problems. A large number of experiments are performed to determine the influence of the parameters of the GA with the goal to determine the optimal set of parameters. A method is introduced to determine optimal parameters of microgenetic algorithms based on known parameters of the optimal genetic algorithm. An analysis of the microgenetic algorithm based on Markov chains is shown. The conclusions of this analysis are used to introduce the new solution space contraction parameter which increases the precision of the solution. The described algorithm is used to solve the inverse kinematics problem of a hiperredundant robot. The inverse kinematics problem is defined in form of an optimization problem and the chromosome is defined as a vector. The genetic operators are modified to operate with vector chromosomes. The vector form of the genetic algorithm is used to optimize the CAN bus protocol with the goal to reduce jitter at higher bus loads. The microgenetic algorithm for solving the inverse kinematics problem is implemented on several platforms and the genetic algorithm for CAN bus optimization is tested on an existing decentralized control system of an firefighting vehicle.

A new strategy for implementing the concept of a “micro genetic algorithm” within a standard genetic algorithm (GA) procedure is proposed. The strategy operates by applying criteria to test for the occurrence of stagnation within the population of a standard GA calculation, and triggering the micro-GA procedure whenever stagnation is detected. The micro-GA is implemented in terms of the parallel evolution of a number of small sub-populations (comprising predominantly new randomly generated structures together with a few of the best structures from the stagnated population), and the sub-population of highest quality following the micro-GA procedure is used in the construction of the next population of the standard GA calculation. The micro-GA procedure is applied in the context of a GA for carrying out direct-space structure solution from powder X-ray diffraction data, and the results demonstrate that this strategy is an effective means of promoting structural diversity within a stagnated population, leading to significantly improved evolutionary progress. This strategy may prove to be more generally applicable as an approach for alleviating problems due to stagnation in GA calculations in other fields of application.

We propose a low-profile high-gain electromagnetic band-gap (EBG) resonator antenna that utilizes a double-sliced frequency-selective surface (FSS) on a single superstate. In this design, a microgenetic algorithm is employed to optimise the FSS so that the EBG resonator antenna can achieve a directivity of 22 dBi, which is normally achieved by EBG antennas with multiple dielectric layers.

An optimization method based on the microgenetic algorithm (MGA) is presented for the design of multilayered radar absorbing materials made of tetrapod-shaped ZnO whisker. The optimization procedure is designed for a given thickness and the optimization conditions, which are different in order to meet the practical requirements in the different frequency bands (the range of 2~18GHz). The effects of the thickness, the number of layers, and the restrained conditions on the optimization results are discussed in detail.

An optimization technique based on the microgenetic algorithm (MGA) is presented for the design of multilayered radar absorbing materials made of tetrapod-shaped ZnO whisker in this paper. The fast optimization procedure is designed for a given maximum thickness and the optimization conditions are different in order to meet the practical requirements in the different frequency bands (the range of 2/spl sim/18GHz). The effects of the thickness, the number of layers, and the restrained conditions on the optimization results are discussed in detail.

This paper presents a new combination between transmission line matrix method (TLM) and microgenetic algorithm (µGA). This coupling is used to design patch shapes of microstrip and planar inverted—F antennas (PIFA) for broad-band or multi-band applications. Measured results of the µGA/TLM optimized designs show good agreement with TLM simulation. Copyright © 2004 John Wiley & Sons, Ltd.

This paper describes the design of a variable structure PID control system (VSPID) using genetic algorithms. This VSPID has a structure similar to that of the simple PID controller where the PD mode is used to speed up response, whereas the PI mode is applied to eliminate the steady state offset. Flexible changes of controller modes and parameter values of the VSPID could therefore solve the conflict between steady state error and dynamic responsiveness. Due to the difficulties encountered in the application of traditional analytical and numerical methods for the design of variable structure controllers, a microgenetic algorithm is used for the determination of the controller parameters. uGA is known to converge rapidly with optimal or near optimal results. In order to demonstrate the design procedure the temperature control of an oven is used. Taking the integral of the absolute of the error as the performance measure reveals that the proposed VSPID is better than the simple PID controller.

In public security related applications, many suspicious samples may be a mixture of various chemical components that makes the usual spectral analysis difficult. In this paper, a terahertz spectroscopic statistical analysis method using a microgenetic algorithm (Micro-GA) has been proposed. Various chemical components in the mixture can be identified and the concentration of each component can be estimated based on the known spectral data of the pure chemical components. Five chemical mixtures have been tested using Micro-GA. The simulation results have shown agreement with other analytical methods. It is suggested that Micro-GA has potential applications for terahertz spectral identifications of chemical mixtures.