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The modelling of the electromagnetic devices with moving objects such as launchers, electrical machines and actuators, necessitates considering the motion. This paper aims to examine this subject.

This task can be performed by introducing the velocity term in the electromagnetic equation. However, the application of this method leads to a non‐symmetrical finite element matrix. This numerical problem can be avoided either by the finite element meshing domain every displacement step or by using special techniques coupled to the finite element method like the moving bound, sliding surface and macro element (ME). The ME solution, based on an analytical model in the air‐gap of the devices, is more solicited for its low cost and accuracy by comparison with the other one. This technique keeps unchanged the finite element topology during the simulation, where the motion is taken into account by modification of the ME formula's every displacement.

This paper sought to present a new formula of the ME which is called dynamic ME. This new formula keeps unchanged the finite element topology and the terms of the analytical stiffness matrix too during the movement simulation.

The developed model is limited to analyzing the 2D devices with moving objects in linear or non‐linear case with saturation of the magnetic circuits. Extending the model to consider the 3D effects is the perspective of this work.

The developed formula is more economical than the classical one.

Our perception and analysis gradually grow and mature from subjectivity to objectivity as we investigate different periods of society and widen the temporal and spatial framework. The egocentric viewpoint is responsible for some of humanity's greatest mistakes and social crises throughout history. Without perceiving the ‘other’ and considering individuals who are different from them, societies will not be able to create permanent solutions. Although the answers offered are appropriate for one's own civilisation, when looking at the problem from a global perspective, it is extremely likely that there will be a significant incompatibility with other nations and societies. In this context, while our study advises a method of approaching social arrangements regardless of location, particularly time period, it also provides analysis. So much so that today's analysis differs from yesterday's, and tomorrow's will differ even more from today's. Today, more than 80% of the population lives in cities, and this trend is expected to continue. We find that the perceptions of the demands of generations x, y, z and alpha, living today in the same time period, for public goods and/or services, and the value they place on them, are considerably different in the demographic segment, which continues to develop and grow.

Our study intends to explain, on a worldwide scale, how the value ascribed to events, objects and phenomena differentiate these perceptions through social observations and bilateral interviews with these people living simultaneously in an urban environment. Despite the fact that our research will define a geographical area as an urban area in terms of scope, it will also present examples of these urban areas from other countries throughout the world, putting the problem in a global context. Our sample comprises the major cities of the countries with the most people on each continent, whereas our study universe spans the entire globe. It is about observing the values given to these generations' perceptions of urban services in these capitals, ensuring that generations better understand each other based on these findings and reforming the production and presentation of urban goods and/or services based on these findings. Developed and emerging countries are the focus of our judgements and observations.

Eddy current testing (ECT) is a nondestructive testing method for the detection of flaws that uses electromagnetic induction to find defects in conductive materials. In this method, eddy currents are generated in a conductive material by a changing magnetic field. A defect is detected when there is a disruption in the flow of the eddy current. The purpose of this paper is to develop a new noniterative inversion methodology for detecting degradation (defect characterization) such as cracking, corrosion and erosion from the measurement of the impedance variations.

The methodology is based on multi-output support vector machines (SVM) combined with the adaptive database schema design method (SDM). The forward problem was solved numerically using finite element method (FEM), with its accuracy experimentally verified. The multi-output SVM is a statistical learning method that has good generalization capability and learning performance. FEM is used to create the adaptive database required to train the multi-output SVM and the genetic algorithm is used to tune the parameters of multi-output SVM model.

The results show the applicability of multi-output SVM to solve eddy current inverse problems instead of using traditional iterative inversion methods which can be very time-consuming. With the experimental results the authors demonstrate the accuracy which can be provided by the multi-output SVM technique.

The work allows extending the capability of the experimentation ECT defect characterization system developed at LGEP.

A new inversion method is developed and applied to ECT defect characterization. This new concept introduces multi-output SVM in the context of ECT. The real data together with estimated one obtained by multi-output SVM model are compared in order to evaluate the effectiveness of the developed technique.

Reducing eddy current losses in magnets of electrical machines can be obtained by means of several techniques. The magnet segmentation is the most popular one. It imposes the least restrictions on machine performances. This paper investigates the effectiveness of the magnet circumferential segmentation technique to reduce these undesirable losses. The full and partial magnet segmentation are both studied for a frequency range from few Hz to a dozen of kHz. To increase the efficiency of these techniques to reduce losses for any working frequency, an optimization strategy based on coupling of finite elements analysis and genetic algorithm is applied. The purpose of this paper is to define the parameters of the total and partial segmentation that can ensure the best reduction of eddy current losses.

First, a model to analyze eddy current losses is presented. Second, the effectiveness of full and partial magnet circumferential segmentation to reduce eddy loss is studied for a range of frequencies from few Hz to a dozen of kHz. To achieve these purposes a 2-D finite element model is developed under MATLAB environment. In a third step of the work, an optimization process is applied to adjust the segmentation design parameters for best reduction of eddy current losses in case of surface mounted permanent magnets synchronous machine.

In case of the skin effect operating, both full and partial magnet segmentations can lead to eddy current losses increases. Such deviations of magnet segmentation techniques can be avoided by an appropriate choice of their design parameters.

Few works are dedicated to investigate partial magnet segmentation for eddy current losses reduction. This paper studied the effectiveness and behaviour of partial segmentation for different frequency ranges. To avoid eventual anomalies related to the skin effect an optimization process based on the association of the finite elements analysis to genetic algorithm method is adopted.

This paper aims to deal with the development of a newly improved version of teaching learning based optimization (TLBO) algorithm.

Random local search part was added to the classic optimization process with TLBO. The new version is called TLBO algorithm with random local search (TLBO-RLS).

At first step and to validate the effectiveness of the new proposed version of the TLBO algorithm, it was applied to a set of two standard benchmark problems. After, it was used jointly with two-dimensional non-linear finite element method to solve the TEAM workshop problem 25, where the results were compared with those resulting from classical TLBO, bat algorithm, hybrid TLBO, Nelder–Mead simplex method and other referenced work.

New TLBO-RLS proposed algorithm contains a part of random local search, which allows good exploitation of the solution space. Therefore, TLBO-RLS provides better solution quality than classic TLBO.

An investigation was conducted into the impact of various process parameters on the surface and subsurface quality of glass-ceramic materials, as well as the mechanism of material removal and crack formation, through the use of ultrasonic-assisted grinding.

A mathematical model of crack propagation in ultrasonic-assisted grinding was established, and the mechanism of crack formation was described through the model. A series of simulations and experiments were conducted to investigate the impact of process parameters on crack depth, surface roughness, and surface topography during ultrasonic-assisted surface and axial grinding. Additionally, the mechanism of crack formation was explored.

During ultrasonic-assisted grinding, the average grinding forces are between 0.4–1.0 N, which is much smaller than that of ordinary grinding (1.0–3.5 N). In surface grinding, the maximum surface stresses between the workpiece and the tool gradually decrease with the tool speed. The surface stresses of the workpiece increase with the grinding depth, and the depth of subsurface cracks increases with the grinding depth. With the increase of the axial grinding speed, the subsurface damage depth increases. The roughness increases from 0.780um/1.433um.

A mathematical model of crack propagation in ultrasonic-assisted grinding was established, and the mechanism of crack formation was described through the model. The deformation involved in the grinding process is large, and the FEM-SPH modeling method is used to solve the problem that the results of the traditional finite element method are not convergent and the calculation efficiency is low.

The purpose of this paper is to propose an new online path planning method for porcine belly cutting. With the proliferation in demand for the automatic systems of pork production, the development of efficient and robust meat cutting algorithms are hot issues. The uncertain and dynamic nature of the online porcine belly cutting imposes a challenge for the robot to identify and cut efficiently and accurately. Based on the above challenges, an online porcine belly cutting method using 3D laser point cloud is proposed.

The robotic cutting system is composed of an industrial robotic manipulator, customized tools, a laser sensor and a PC.

Analysis of experimental results shows that by comparing with machine vision, laser sensor-based robot cutting has more advantages, and it can handle different carcass sizes.

An image pyramid method is used for dimensionality reduction of the 3D laser point cloud. From a detailed analysis of the outward and inward cutting errors, the outward cutting error is the limiting condition for reducing the segments by segmentation algorithm.

A meat quality grading system is essential to meet consumers' increasingly diversified demand for food quality in the global market. This study aims to determine the effectiveness of the upcoming Chinese quality grading labels and examine the information effect of labeling standards on pork consumption choices.

Using an online survey with choice experiments, this study estimates consumer valuation for the fat thickness of different pork primal cuts by simulating three scenarios. Generalized mixed logit models in WTP space are used to analyze the choice experiment data.

Chinese consumers prefer lean pork to fatty pork and this preference does not vary significantly between primal cuts. Consumer valuation for ungraded high-quality (lean) pork increases after the implementation of the quality grading. Meanwhile, they are willing to pay high premiums for labeled pork (including level 1, 2, 3), and there are higher premiums for pork with higher levels. Besides, incomplete information on labeling standards could achieve more premiums for pork than relatively complete information.

This study pays attention to essential but few-noticed pork quality grading. The findings provide references for pork industry practices and policy-making of the meat quality grading system in China and globally by examining incomplete and relatively complete information effects on consumer choices.

Our research identifies political explicitness as a variable property among free spaces and its implications for the role that such spaces can potentially play vis-à-vis social movement mobilization. Specifically, spaces where politics are implicit (i.e., where political goals and values are not an explicit part of associative principles) can serve as sites where identities with affinities to social movements are cultivated while remaining open to those who do not already hold sympathetic views – representing free and open spaces. Our research draws on previously unexplored links between social movement research and leisure activity research, which explains processes of socialization across participant levels as a central dynamic in shaping collective values and individual participant identities. We illustrate our argument by exploring those processes within American belly dance as an example of a gendered leisure activity, and their influence on participants’ gender identity and related political attitudes. Findings are based on survey research of 103 dancers in the Salt Lake City, Utah, region. Data indicate wide acceptance of gender norm challenges, and affirm expectations of leisure activity research regarding community dynamics that promote such challenges.