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Proper platform pose is important for the mobile manipulator to accomplish dexterous manipulation tasks efficiently and safely, and the evaluation criterion to qualify manipulation performance is critical to support the pose decision process. This paper aims to present a comprehensive index to evaluate the manipulator’s operation performance from various aspects.

In this research, a criterion called hybrid manipulability (HM) is proposed to assess the performance of the manipulator’s operation, considering crucial factors such as joint limits, obstacle avoidance and stability. The determination of the optimal platform pose is achieved by selecting the pose that maximizes the HM within the feasible inverse reachability map associated with the target object.

A self-built mobile manipulator is adopted as the experimental platform, and the feasibility of the proposed method is experimentally verified in the context of object-grasping tasks both in simulation and practice.

The proposed HM extends upon the conventional notion of manipulability by incorporating additional factors, including the manipulator’s joint limits, the obstacle avoidance situation during the operation and the manipulation stability when grasping the target object. The manipulator can achieve enhanced stability during grasping when positioned in the pose determined by the HM.

The purpose of this paper is mainly to develop the adjoint method within the method of magnetic moment (MMM) and thus, to provide an efficient new way to solve topology optimization problems in magnetostatic to design 3D-magnetic circuits.

First, the MMM is recalled and the optimization design problem is reformulated as a partial derivative equation-constrained optimization problem where the constraint is the Maxwell equation in magnetostatic. From the Karush–Khun–Tucker optimality conditions, a new problem is derived which depends on a Lagrangian parameter. This problem is called the adjoint problem and the Lagrangian parameter is called the adjoint parameter. Thus, solving the direct and the adjoint problems, the values of the objective function as well as its gradient can be efficiently obtained. To obtain a topology optimization code, a semi isotropic material with penalization (SIMP) relaxed-penalization approach associated with an optimization based on gradient descent steps has been developed and used.

In this paper, the authors provide theoretical results which make it possible to compute the gradient via the continuous adjoint of the MMMs. A code was developed and it was validated by comparing it with a finite difference method. Thus, a topology optimization code associating this adjoint based gradient computations and SIMP penalization technique was developed and its efficiency was shown by solving a 3D design problem in magnetostatic.

This research is limited to the design of systems in magnetostatic using the linearity of the materials. The simple examples, the authors provided, are just done to validate our theoretical results and some extensions of our topology optimization code have to be done to solve more interesting design cases.

The problem of design is a 3D magnetic circuit. The 2D optimization problems are well known and several methods of resolution have been introduced, but rare are the problems using the adjoint method in 3D. Moreover, the association with the MMMs has never been treated yet. The authors show in this paper that this association could provide gains in CPU time.

The purpose of this paper is to present a new approach to optimizing the design of 3D magnetic circuits. This approach is based on topology optimization, where derivative calculations are performed using the continuous adjoint method. Thus, the continuous adjoint method for magnetostatics has to be developed in 3D and has to be combined with penalization, filtering and homotopy approaches to provide an efficient optimization code.

To provide this new topology optimization code, this study starts from 2D magnetostatic results to perform the sensitivity analysis, and this approach is extended to 3D. From this sensitivity analysis, the continuous adjoint method is derived to compute the gradient of an objective function of a 3D topological optimization design problem. From this result, this design problem is discretized and can then be solved by finite element software. Thus, by adding the solid isotropic material with penalization (SIMP) penalization approach and developing a homotopy-based optimization algorithm, an interesting means for designing 3D magnetic circuits is provided.

In this paper, the 3D continuous adjoint method for magnetostatic problems involving an objective least-squares function is presented. Based on 2D results, new theoretical results for developing sensitivity analysis in 3D taking into account different parameters including the ferromagnetic material, the current density and the magnetization are provided. Then, by discretizing, filtering and penalizing using SIMP approaches, a topology optimization code has been derived to address only the ferromagnetic material parameters. Based on this efficient gradient computation method, a homotopy-based optimization algorithm for solving large-scale 3D design problems is developed.

In this paper, an approach based on topology optimization to solve 3D magnetostatic design problems when an objective least-squares function is involved is proposed. This approach is based on the continuous adjoint method derived for 3D magnetostatic design problems. The effectiveness of this topology optimization code is demonstrated by solving the design of a 3D magnetic circuit with up to 100,000 design variables.

This study aims to propose a general methodology to handle multimaterial filtering for density-based topology optimization containing periodic or antiperiodic boundary conditions, which are expected to reduce the simulation time of electrical machines. The optimization of the material distribution in a permanent magnet synchronous machine rotor illustrates the relevance of this approach.

The optimization algorithm relies on an augmented Lagrangian with a projected gradient descent. The 2D finite element method computes the physical and adjoint states to evaluate the objective function and its sensitivities. Concerning regularization, a mathematical development leads to a multimaterial convolution filtering methodology that is consistent with the boundary conditions and helps eliminate artifacts.

The method behaves as expected and shows the superiority of multimaterial topology optimization over bimaterial topology optimization for the chosen test case. Unlike the standard approach that uses a cropped convolution kernel, the proposed methodology does not artificially reflect the limits of the simulation domain in the optimized material distribution.

Although filtering is a standard tool in topology optimization, no attention has previously been paid to the influence of periodic or antiperiodic boundary conditions when dealing with different natures of materials. The comparison between the bimaterial and multimaterial topology optimization of a permanent magnet machine rotor without symmetry constraints constitutes another originality of this work.

The purpose of this study is to investigate the role of sales, as a proxy for size, in moderating the impact of institutional incongruence between formal and informal institutions on the formalization of microenterprises in middle-income countries in Latin America.

The paper uses a probit regression model to examine business formalization as a binary outcome of formal and informal institutions. Data was collected through interviews and surveys across 52 municipalities in the Metropolitan Region of Santiago, Chile. The study used a stratified sampling approach and was conducted between November 2022 and January 2023.

The results offer three key insights into the formalization of microenterprises in middle-income countries. First, we show that formal institutions do not significantly influence formalization decisions among microentrepreneurs in middle-income countries, challenging the traditional belief that formal institutions alone significantly influence formalization in these contexts. Second, we show that informal institutions are significant predictors of informality, especially among smaller microenterprises. Third, we highlight that the smaller the business, the stronger the negative effect of informal institutions on formalization, and thus, the institutional incongruence between formal and informal institutions decreases for larger businesses.

This paper contributes to management literature by shedding light on the drivers of formalization in middle-income countries, a departure from most formalization studies wherein the focus is primarily on low-income economies. The findings suggest that policymakers in middle-income countries should focus on enabling microenterprise growth through sales, rather than targeting specific demographic groups or relying solely on formal institutional enforcement to promote formalization.

El objetivo de este estudio es investigar el papel de las ventas, utilizadas como un indicador de tamaño, en la mediación del impacto de la incongruencia institucional entre instituciones formales e informales en la formalización de microempresas en países de ingresos medios en América Latina.

Utilizamos un modelo de regresión Probit para examinar la formalización empresarial como un resultado binario de instituciones formales e informales. Los datos se recopilaron a través de 110 entrevistas y encuestas en 52 municipios de la Región Metropolitana de Santiago, Chile. El estudio empleó un enfoque de muestreo estratificado y se llevó a cabo entre noviembre de 2022 y enero de 2023.

Nuestros resultados ofrecen tres ideas clave sobre la formalización de microempresas en países de ingresos medios. Primero, demostramos que las instituciones formales no influyen significativamente en las decisiones de formalización entre las microempresas en países de ingresos medios; esto desafía la creencia tradicional de que las instituciones formales por sí solas influyen significativamente en la formalización en estos contextos. Segundo, nuestro estudio muestra que las instituciones informales son predictores significativos de la informalidad, especialmente entre las microempresas más pequeñas. Tercero, nuestro estudio destaca que el efecto negativo de las instituciones informales sobre la formalización es más fuerte para negocios de menor tamaño; por lo tanto, la incongruencia institucional entre instituciones formales e informales disminuye para negocios de mayor tamaño.

Este artículo contribuye a la literatura iluminando sobre los impulsores de la formalización en países de ingresos medios, a diferencia de la mayoría de los estudios de formalización en la región latinoamericana que se centran principalmente en países de bajos ingresos. Nuestros hallazgos sugieren que los responsables de políticas en países de ingresos medios deberían centrarse en impulsar el crecimiento de las microempresas a través de las ventas, en lugar de enfocarse en grupos demográficos específicos o depender únicamente del cumplimiento institucional formal para promover la formalización.

O objetivo deste estudo é investigar o papel das vendas, usadas como um indicador de tamanho, na mediação do impacto da incongruência institucional entre instituições formais e informais na formalização de microempresas em países de renda média na América Latina.

Utilizamos um modelo de regressão Probit para examinar a formalização empresarial como um resultado binário de instituições formais e informais. Os dados foram coletados por meio de 110 entrevistas e pesquisas em 52 municípios da Região Metropolitana de Santiago, Chile. O estudo empregou uma abordagem de amostragem estratificada e foi realizado entre novembro de 2022 e janeiro de 2023.

Nossos resultados oferecem três ideias-chave sobre a formalização de microempresas em países de renda média. Primeiro, demonstramos que as instituições formais não influenciam significativamente as decisões de formalização entre as microempresas em países de renda média; isso desafia a crença tradicional de que as instituições formais, por si só, influenciam significativamente a formalização nesses contextos. Segundo, nosso estudo mostra que as instituições informais são preditores significativos da informalidade, especialmente entre as microempresas menores. Terceiro, nosso estudo destaca que o efeito negativo das instituições informais sobre a formalização é mais forte para negócios de menor porte; portanto, a incongruência institucional entre instituições formais e informais diminui para negócios de maior porte.

Este artigo contribui para a literatura iluminando os impulsionadores da formalização em países de renda média, ao contrário da maioria dos estudos de formalização na região latino-americana, que se concentram principalmente em países de baixa renda. Nossos achados sugerem que os responsáveis pelas políticas em países de renda média deveriam focar em impulsionar o crescimento das microempresas por meio das vendas, em vez de se concentrar em grupos demográficos específicos ou depender exclusivamente do cumprimento institucional formal para promover a formalização.

Extensive empirical evidence suggests that procedural justice (PJ) and distributive justice (DJ) are key success factors for achieving durable peace negotiations. This paper aims to investigate how complexity affects these factors and the outcomes in negotiations.

The qualitative study is based on an examination of the peace negotiations that led to the 2016 agreement between the Fuerzas Armadas Revolucionarias de Colombia – Ejército del Pueblo and the Colombian Government. Based on document analysis, the authors examined in detail how and where in the process the principles of PJ and DJ were applied. The authors then examined the implementation progress after 2016 and placed the peace process in the overall context of the Colombian conflict.

The authors found that the principles of PJ and DJ were present in both the negotiation process and the agreement. The negotiations were successful and satisfactory solutions could be found for all issues. The complexity of the conflict is reflected in the limited coverage of the peace negotiations. Not all groups, interests and subconflicts could be included in the negotiations. This limits their contribution to a durable peace in Colombia. Conflicts that remain unresolved also have a negative effect on the implementation of the agreement.

For conflict management, this implies that the negotiations should not be viewed as “one-and-done” but rather as a progressive, ongoing process. The agreement is only the nucleus for achieving total peace. It must be actively advanced and defended.

This study offers new qualitative insights into how PJ and DJ function in negotiations. It also establishes a systematic connection between PJ and DJ and complexity, introduces the notion of coverage and, thereby, opens a new perspective on the management of conflict complexity.

The concept of Circular Economy (CE) has gained significant traction in addressing the issue of Construction and Demolition (C&D) waste, which is generated because of global urbanisation and urban renewal. Therefore, this research aims to explore the applicability of CE strategies to minimise the C&D Waste Management (WM) issues in Sri Lanka considering the preconstruction stage of the building project.

The research adopted a qualitative approach, using three expert interview rounds with the Delphi technique. In each round, 17, 15 and 12 experts were involved. A manual content analysis method was used to analyse the collected data.

Findings uncovered effective strategies in CE to address the 14 issues within C&D WM and its effects on the project management iron triangle in Sri Lanka. Integrating CE strategies within the construction sector to tackle C&D WM issues can significantly contribute to establishing a more sustainable, robust and resource-conscious built environment. By adopting CE strategies such as design for adaptability of existing buildings and design for disassembly, construction projects can optimise the project's timeline, cost and quality factors.

This will help to minimise the demand for virgin materials and reduce the volume of waste generated. Using recycled materials also helps close the loop of the materials cycle, thereby contributing to the CE. Also, this research contributes uniquely by offering practical, context-driven solutions that align with Sri Lanka’s construction sector.

The purpose of this study is to explore the plurality of logics composing an organizational field and how that plurality affects a sport governing body's (SGB) sense of self. The authors sought to determine what logics exist in a specific field and how they interact according to Kraatz and Block's (2017) types of organizational responses. Finally, the authors explore how an organization's responses affect organizational outcomes.

The authors analyzed 476 unique organizational web pages and documents and 293 news media articles from four news outlets. The authors conduct a content analysis informed by Gioia et al.’s (2013) method to explore the website data to understand the logics of the field. The authors analyze the media articles for media accounts of events and determine how logics inform an SGB's actions (Cocchairella and Edwards, 2020).

The authors find institutional plurality leads to a fractured organizational sense of self, resulting in poor outcomes. The authors' findings suggest Kraatz and Block's (2017) as well as other previously theorized strategies do not lead to an organization reconciling competing logics. Rather, the strategies employed led to outcomes harming the organization's legitimacy and financial well-being.

There are several calls within the broader management field and the sport management field to address institutional plurality (Kraatz and Block, 2017; Robertson et al., 2022). Unlike previous research studies, this study finds detrimental effects of plurality on an organization. The authors discuss the strength of the strategies employed and why the strategies failed.

The article investigates whether and to what extent outsiderness is gendered in Western Europe, both in terms of its spread and degree. It thus explores which male and female post-Fordist social classes are more exposed to the risk of this phenomenon. It also scrutinizes whether such a gendered characterization has varied over time and across clusters of Western European countries.

Relying on a comparative analysis of the data provided by the European Social Survey (ESS) dataset and comparing two points in time – the early/mid-2000s and the late 2010s – the work provides both a dichotomous and continuous variable of outsiderness, which measure its spread and degree in the female and male workforces of a pooled set of growth models.

The empirical analysis shows that outsiderness is profoundly gendered in Western Europe and thus a feminized social phenomenon. However, the comparative investigation highlights that outsiderness has been genderized in diverse ways across the four growth models. Different patterns of gendered outsiderness can be identified.

The article provides a comparative and diachronic analysis of outsiderness from a gender lens, putting into a mutual dialogue different literature on labour market, and shows that outsiderness represents a key analytical dimension for assessing gender inequalities.

The United States is unique in how it imposes income taxation on their citizens living overseas, as if they lived in the United States. Neither US residents (regardless of citizenship) nor non-US citizens residing overseas are subjected to such a penalising system. The system is justified by the stigmatisation of overseas Americans as necessarily wealthy and whose purpose in living overseas is to avoid US taxation.

Because of penalising US taxation, overseas Americans struggle with ordinary activities required to sustain modern life. The activities include owning a home, holding a bank account, investing and planning for retirement, operating a business, holding certain jobs, and pursuing community service opportunities. The situation causes many to feel that they have no choice but to renounce US citizenship.

Ultimately, the question must be asked: Are Americans free to live outside the United States?