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The definition of a simple model of low frequency magnetic field created by power industrial installations can be approached by using an equivalent source system (ESS). Given a set of measured magnetic field points, the ESS, made by a limited set of current carrying wires or turns, must be placed and supplied in order to fit the measured magnetic field values. An optimisation procedure can be used to define the current values and the location of the ESS which minimize the error between the measured and computed magnetic field values.

A two‐step optimal procedure is defined: in the outer step a stochastic optimisation routine is used to drive the geometric control parameters of the ESS while, in the inner step, the current values flowing through the sources are computed to find the minimization of the error with respect to a set of measured magnetic field values. The optimisation procedure is based on an artificial immune system algorithm which focuses on a deep exploration of the search space and gave interesting results both in terms of accuracy and computational efficiency.

The results show that the proposed approach is able to reconstruct the magnetic field created by complex source system and give some accuracy measure on the reconstruction error. The optimisation process carried out also on conductor positions has allowed to find out the location of the real sources in an accurate way, also in presence of measurement errors.

The approach proposed uses optimisation procedures to solve the inverse problem of source reconstruction starting by a set of measured magnetic field values. The definition of a simple equivalent source structure, together with an optimisation procedure to set its control parameters, allows to simulate complex magnetic field sources, like power substations or cable systems, in a very efficient and compact way.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

The purpose of this paper is to present an approach to design passive loop systems in order to reach good performances.

The optimization has been performed by means of the MATLAB optimization toolbox “Gatool” which solves the optimization problems with a genetic algorithm.

Several configurations have been analyzed by varying the number of loops from 2 to 15, whose geometry has been chosen by the genetic algorithm. Considering a five loops configuration, along the reference path it is possible to obtain a shielding factor almost constant and equal to 3.5.

The optimized configurations have been compared with a practical employed layout composed of 17 closed loops placed above and around the junction zone. The shielding factors obtained by the six loops configuration are comparable with the ones of the practical layout.

The purpose of this study is to investigate and compare the ability of a new optimization technique based on the emulation of the immune system to detect the global maximum with multimodal functions and to test the capability of exploring the parameter space with respect to clustering enhanced Genetic Algorithms (GA).

Both algorithms have been tested on analytical test functions and on numerical functions of applicative interest. A set of performance criteria has been defined in order to numerically compare the performances of both optimization strategies.

Results show the great ability of Artificial Immune Systems (AIS) in thoroughly exploring the space of variables. On the other side, GA are faster to converge to the global optimum, but selection pressure can reduce the number of detected local optima.

This work is an attempt to assess the performances of a relatively new optimization algorithm based on AIS and to find its behavior on multimodal test functions, using GAs as reference optimization technique.

A finite‐element formulation is developed to analyze nonlinear electromagnetic devices in steady‐state conditions under specified alternating terminal voltages. The circuit equations are used to express current densities in terms of the unknown vector potential, so that only one nonlinear field equation must be solved. The mathematical formulation and the finite‐element and Fourier approximations are developed and the numerical algorithm used to solve the resulting block system is discussed. Finally, an application of the method to analyze an electromagnet with shading coils is presented.

In March 2020, we opened our classrooms to students, parents, and the world. Zoom and Google Meet became the new spaces to gather as regular check-ins with students and families became the norm. Educators served students through a two-way window where we previously only saw them in the school setting and now with the use of technology, could literally see into their homes. It is evident to many that inequities exist among the students and families that we serve, and our efforts to care them focused on social-emotional learning and supporting their well-being. While many see the challenges that the pandemic brought, there were also many opportunities that came about, including the use of core values which helped guide us through uncertainty. The need for human connection became a clear factor when we were not able to be together physically. Connecting with students and families on an authentic, deeper level, shifted how we think about school leadership and improving schools. The mindset transitioning to our ability to teach in schools and communities, not just in a physical classroom, became one of our guiding principles. Across the United States, school districts’ instructional directives varied greatly. In our district, leaders came together to create virtual lessons to be available for all students. Our focus was to support educational equity and to give students opportunities to engage with grade level curriculum at any time of day (or night).

The purpose of this paper is to review recent applications of functional magnetic resonance imaging (fMRI) and other neuroimaging techniques in marketing and advertising, and to present some methodological and statistical considerations that should be taken into consideration when applying fMRI to study consumers’ cognitive behavior related to marketing phenomena.

A critical approach to investigate three methodological issues related to fMRI applications in marketing is adopted. These issues deal mainly with brain activation regions, event-related fMRI and signal-to-noise ratio. Statistical issues related to fMRI data pre-processing, analyzing and reporting are also investigated.

Neuroimaging cognitive techniques have great potential in marketing and advertising. This is because, unlike conventional marketing research methods, neuroimaging data are much less susceptible to social desirability and “interviewer’s” effect. Thus, it is expected that using neuroimaging methods to investigate which areas in a consumer’s brain are activated in response to a specific marketing stimulus can provide a much more honest indicator of their cognition compared to traditional marketing research tools such as focus groups and questionnaires.

By merging disparate fields, such as marketing, neuroscience and cognitive psychology, this research presents a comprehensive critical review of how neuroscientific methods can be used to test existing marketing theories.

Stereolithography (SLA) additive manufacturing (AM) technique has enabled the production of inconspicuous and aesthetically pleasing orthodontics that are also hygienic. However, the staircase effect poses a challenge to the application of invisible orthodontics in the dental industry. The purpose of this study is to implement chemical postprocessing technique by using isopropyl alcohol as a solvent to overcome this challenge.

Fifteen experiments were conducted using a D-optimal design to investigate the effect of different concentrations and postprocessing times on the surface roughness, material removal rate (MRR), hardness and cost of SLA dental parts required for creating a clear customized aligner, and a container was constructed for chemical treatment of these parts made from photocurable resin.

The study revealed that the chemical postprocessing technique can significantly improve the surface roughness of dental SLA parts, but improper selection of concentration and time can lead to poor surface roughness. The optimal surface roughness was achieved with a concentration of 90 and a time of 37.5. Moreover, the dental part with the lowest concentration and time (60% and 15 min, respectively) had the lowest MRR and the highest hardness. The part with the highest concentration and time required the greatest budget allocation. Finally, the results of the multiobjective optimization analysis aligned with the experimental data.

This paper sheds light on a previously underestimated aspect, which is the pivotal role of chemical postprocessing in mitigating the adverse impact of stair case effect. This nuanced perspective contributes to the broader discourse on AM methodologies, establishing a novel pathway for advancing the capabilities of SLA in dental application.

This paper aims to investigate the influence of post-curing temperature, post-curing time and gamma ray irradiation dose upon the tensile and compressive mechanical properties of the medical graded vat photopolymerization parts.

Medical graded vat photopolymerization specimens, made from photopolymer resin, were fabricated using bottom-up vat photopolymerization machine. Tensile and compressive tests were conducted to assess the mechanical properties. The specimens were categorized into uncured and post-curing groups. Temperature post-processing and/or gamma irradiation exposure were for post-curing specimens. The post-curing parameters considered included temperature levels of 50°C, 60°C and 70°C, with 1, 2, 3 and 4 h periods. For the gamma irradiation, the exposure doses were 25, 50, 75 and 100 kGy.

Post-curing improved the mechanical properties of medical graded vat photopolymerization parts for both tensile and compressive specimens. Post-curing temperature greater than 50°C or a prolonged post-curing period of more than 1 h made insignificant changes or deterioration in mechanical properties. The optimal post-curing condition was therefore a 50°C post-curing temperature with 1 h post-curing time. Exposure to gamma ray improved the compressive mechanical properties, but deteriorated tensile mechanical properties. Higher gamma irradiation doses could decrease the mechanical properties and also make the part more brittle, especially for doses more than 25 kGy.

The obtained results would be beneficial to the medical device manufacturer who fabricated the invasive temporary contact personalized surgical instruments by vat photopolymerization technique. In addition, it also raised awareness in excessive gamma sterilization in the medical graded vat photopolymerization parts.

The purpose of this paper is to present a new concept of passive loop technique called “high magnetic coupling passive loop” (HMCPL) (suitable for buried power lines) along with optimised design parameters.

The optimal design (geometrical displacement and shielding current intensity and phase) for the mitigation of magnetic field produced by flat and trefoil configuration of the power line is carried out by means of genetic algorithm.

Different layouts for the source (flat and trefoil configuration) and the shield (introduction of the phase splitting technique) are designed. The optimization parameters are the coordinates of the shield conductors and the transformer ratio of the magnetic core that couple the source and the shield. Moreover, physical constraints as maximum depth of excavation and geometric interference between cables were introduced in the optimization procedure.

The paper deals with a very new technology for field mitigation called HMCPL. Actually, the base layout of the HMCPL does not need an optimal design. On the other hand, in some applications the base layout cannot be used, therefore, the introduction of an optimal design cannot be avoided. In this paper, the optimal design of several configurations is performed showing that the performances of the HMCPL are very interesting even if the base layout cannot be used.