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Static converters generate current harmonics in power grids. For numerous studies, analytical frequency modeling is preferred to carry out their harmonic modeling in the context of sizing by optimization. However, a design by optimization has to consider other constraints, e.g. modeling constraints and operating constraints. In this way, this paper aims to focus on applying an analytical frequency modeling on the sizing by optimization of an aircraft electrical power channel.

The paper aims to size a multiphysical system by optimization. In this way, the sizing of an aircraft electrical power channel by optimization has been carried out. The models of all the channel components are analytical. Specifically, the frequency model of the power electronics is based on Tran et al. (2016) and is made of equalities and inequalities. Due to this modeling choice, the optimization satisfies hundreds of constraints, such as modeling constraints and static converter operating constraints. Furthermore, transient constraints are only verified after optimization.

The difficulty is the modeling of the system by taking into account nonlinear implicit equations having several solutions. A solution is the addition of inequality constraints to the model to guide the implicit solving. Furthermore, this greatly helps the optimization algorithm to find the good operating mode of the static converter, at steady state. This aspect is indispensable to validate the sizing model.

The number of the configurations per operating period of the static converters is defined a priori and limited.

The analytical model for the sizing is formulated as a constrained optimization problem. Its solving and the sizing by optimization are carried out by the same optimization algorithm.

An analytical approach is preferred to carry out the harmonic modelling of power electronics converters because it is generally faster than time simulation chained with FFT. However, the difficulty of such an approach is to build the model and to manage the uncontrolled commutations that occur in the studied static converter, and also to deal with large equations. The purpose of this paper is to propose an aid in the frequency modelling of the drive elements, in the frequency domain, including all key parameters for sizing aim i.e. a way to optimize the EMC filter using different algorithms.

The paper aims to propose an aid to create such models, and to assure its good solving, i.e. that the correct operating mode is represented. So, the solving problem is formulated as an optimization problem under constraints, to solve this difficulty.

The difficulty is to be sure to deal with the good operating mode of the static converter when soft or uncontrolled commutations occur. So, the model is formulated as a constrained optimization problem. The paper proposes a symbolic approach, that allows to build automatically the frequency model. It is translated to be solved in Matlab.

The approach does not fit for static converters with a control implying numerous commutations per operating period. However, the approach deals with natural and soft commutations.

The modelling is based on the use of linear components and ideal switches.

The purpose of this paper is to describe an optimization methodology based on a mixed (analytical‐numerical) design model and evolutionary algorithms.

In this paper, optimal sizing is used to design the new architecture of an embedded electrical system. An approach is presented for defining the specifications and a method for modeling an embedded electrical network. This will enable the optimization problem to be set.

This paper shows that the proposed methodology is useful for sizing an embedded electrical system. It is illustrated by its application to the sizing of an aircraft electrical power channel (auto‐transformer‐rectifier unit type).

An original approach is proposed for limiting the search space before using the evolutionary algorithms. The advantage of this approach is to increase convergence speed of the evolutionary algorithms.

This paper aims to explore ethnic minority women’s gendered perceptions and processes of agricultural innovation in the Northern uplands of Vietnam. The key research question asks how women develop innovations and learn new agricultural practices within patriarchal family structures.

In-depth interviews including life histories were conducted with 17 female and 10 male farmers from different socio-economic groups; participant observation and key informant interviews were also carried out.

Women’s innovation processes are deeply embedded in their positions as wives and daughters-in-law. Their innovation tends to be incremental, small-scale and less technological, and they use innovation networks of women rather than those of the formal agricultural institutions, including bringing innovation knowledge from their birth family to the patrilocal household. Unlike men’s perceived innovation, women’s innovation is strongly linked to small-scale entrepreneurship, and it is a powerful approach in the sense that it strengthens the position of women in their families while improving the household economy.

Identifying socially constructed innovation processes helps policymakers to rethink the introduction of ready-made innovation packages, both in terms of content and delivery, and to facilitate innovation for women, as well as men, in marginalized positions.

Understanding the gendered processes of innovation instead of measuring gender gaps in innovation outcomes sheds light on women’s interests and preferences, which can inform policies for supporting women’s innovation and thereby lead to social change, including gender equity.

This paper contributes to the understanding of gendered innovation processes and entrepreneurship associated with agriculture in rural areas in non-Western ethnic-minority contexts, which is an area that past and current research on entrepreneurship has relatively ignored.