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South America is a heterogeneous continent, with diverse prison realities. Its prison population is estimated at 600,000 inmates, of whom 10,000 are declared insane. Physical and mental health care supplied to the inmates is precarious and preventive programs in progress are rare. The authors’ comment on the Roman Law tradition and describe the situation in Brazil and Argentina, from the point of view of their legal backgrounds. They also consider the kind of mental health resources found and the types of treatment offered, mainly in Forensic Psychiatric Hospitals. Their conclusion emphasizes the need to improve the conditions of penitentiaries in South America, which, because of their deficiencies, often violate the human rights of prisoners.

Fused filament fabrication of continuous-fiber-reinforced polymers is a promising technique to achieve customized high-performance composites. However, the off-axis tensile strength (TS) and Mode I fracture toughness of fused filament fabricated (FFFed) continuous-glass-fiber-reinforced (CGFR) nylon are unknown. The purpose of this paper is to investigate the mechanical and fracture behavior of FFFed CGFR nylon with various fiber content and off-axis fiber alignment.

Tensile tests were performed on FFFed CGFR-nylon with 9.5, 18.9 and 28.4 fiber vol. %. TS was tested with fiber orientations between 0^∘ and 90^∘ at 15^∘ intervals. Double cantilever beam tests were performed to reveal the Mode I fracture toughness of FFFed composites.

TS increased with increasing fiber vol. % from 122 MPa at 9.5 vol. % to 291 MPa at 28 vol. %. FFFed nylon with a triangular infill resulted in 37 vol. % porosity and a TS of 12 MPa. Composite samples had 11–12 vol. % porosity. TS decreased by 78% from 291 MPa to 64 MPa for a change in fiber angle θ from 0^∘ (parallel to the tensile stress) to 15^∘. TS was between 27 and 17 MPa for 300 < θ < 900. Mode I fracture toughness of all the composites were lower than ∼332 J/m2.

Practical applications of FFFed continuous-fiber-reinforced (CFR) nylon should be limited to designs where tensile stresses align within 15^∘ of the fiber orientation. Interlayer fracture toughness of FFFed CFR composites should be confirmed for product designs that operate under Mode I loading.

To the best of the authors’ knowledge, this is the first study showing the effects of fiber orientation on the mechanical behavior and effects of the fiber content on the Mode I fracture toughness of FFFed CGFR nylon.

This study focuses on a specific method of meat production that involves carcass purchase and meat production by packing facilities with a novel two-stage model that simultaneously considers location-routing and inventory-production operating decisions. The considered problem aims to reduce variable and fixed transportation and production costs, inventory holding cost and the cost of opening cold storage facilities.

The proposed model encompasses a two-stage model consisting of a single-echelon and a three-echelon many-to-many network with deterministic demand. The proposed model is a mixed-integer linear programming (MILP) model which was tested with the general algebraic modelling system (GAMS) software for a real-world case study in Iran. A sensitivity analysis was performed to examine the effect of retailers' holding capacity and supply capacity at carcass suppliers.

In this research, the number of products transferred at each level, the number of products held, the quantity of red meat produced, the required cold storage facilities and the required vehicles were optimally specified. The outcomes indicated a two percent (2%) decrease in cost per kg of red meat. Eventually, the outcomes of the first and second sensitivity analysis indicated that reduced retailers' holding capacity and supply capacity at carcass suppliers leads to higher total costs.

This research proposes a novel multi-period location-inventory-routing problem for the red meat supply chain in an emerging economy with a heterogeneous vehicle fleet and logistics decisions. The proposed model is presented in two stages and four-echelon including carcass suppliers, packing facilities, cold storage facilities and retailers.

Global leadership research published in the form of journal articles, scholarly book chapters, and theses and dissertations from 2015 to 2020 are tabulated to ascertain patterns in the field regarding the quantity of publication in the field, type of research being conducted, authorship patterns, type of theory that is utilized, and linkages of research to related phenomena. We compare our findings to previous research and discuss implications for the future evolution of the global leadership field.

The aim of this work is to explain the final negotiated prices for some of the most famous transfers of football players over the last twelve years (2007–2018).

The article analyses different values for forwards taken from the sports website Transfermarkt, developing a statistical model based on personal, performance, risk, environmental and popularity variables. From those values, the article finds an explanation for the final prices paid for 20 superstar players based on a combination of real option valuations, incorporating the players' life cycles and game theory.

The authors find that in a large percentage (70%) of the analysed cases, the price paid was higher than the intrinsic market value resulting from Transfermarkt, implying the existence of monopolistic rents, paid as “growth options” on prices from different negotiating conditions. On occasions, the final prices also exceed the value of the growth option, calculated under neutral bargaining conditions, highlighting the lack of economic viability of important transfers, leading to financial difficulties for the clubs involved.

The algorithm provides more flexibility and realism than previous proposals, based on the life cycle of football players, introducing the uncertainty and volatility of projections through Monte Carlo simulation, the capacity of clubs to bargain a price at any point of the contract and finally, the buyer's ability to transfer the player if his subsequent performance is not as expected.

This chapter analyzes the link between the digital divide, infrastructure regulation, and disaster planning and relief through a case study of the flood in San Jose, California triggered by the Anderson dam’s overtopping in February 2017 and an examination of communication failures during the 2018 wildfire in Paradise, California. This chapter theorizes that regulatory decisions construct social and disaster vulnerability. Rooted in the Whole Community approach to disaster planning and relief espoused by the United Nations and the Federal Emergency Management Agency, this chapter calls for leadership to end the digital divide. It highlights the imperative of understanding community information needs and argues for linking strategies to close the digital divide with infrastructure and emergency planning. As the Internet’s integration into society increases, the digital divide diminishes access to societal resources including disaster aid, and exacerbates wildfire, flood, pandemic, and other risks. To mitigate climate change, climate-induced disaster, protect access to social services and the economy, and safeguard democracy, it argues for digital inclusion strategies as a centerpiece of community-centered infrastructure regulation and disaster relief.

This chapter explores queer theory as a “thought of a method” in educational ethnography by sharing stories of two third grade boys and situating them in a discussion of Britzman’s ideas about reading and Butler’s notion of fantasy. The stories are presented as a possible queer educational ethnography, in which the ethnographer writes the fantastic narrative of the boys as they read creatively to reveal and unsettle gender and reading as sites of constraint to which other constraints adhere. The boys’ reading itself is a queer reading of these constraints and as such makes alterity visible and possible. The study and the methodological framework suggest that educational ethnographers and other adults who work in schools should become attuned to the markers of constraint and alterity, so as to recognize, shelter, and maintain the alterity that children make possible. The chapter asserts children must be allowed to read for alterity, and shows how fantastic narratives that emerge from such readings are limited by the hushing of individuals who disallow alterity in classrooms. Ultimately, this chapter is relevant to ethnographers of education in that it suggests that queer theory not only is necessary to narrate and thus shelter the ways that gender can and should be unsettled in classrooms, but also allows us to narrate and shelter other queer urgencies related to fear, violence, and vulnerability that children experience or share in classrooms. Implications for the current climate of school reform based on standardization of curriculum are also discussed.

The purpose is to create an algorithm that optimizes the trajectories that an autonomous vehicle must follow to reduce its energy consumption and reduce the emission of greenhouse gases.

An algorithm is presented that respects the dynamic constraints of the robot, including the characteristics of power delivery by the motor, the behaviour of the tires and the basic inertial parameters. Using quadratic sequential programming with distributed and non-monotonous search direction (Quadratic Programming Algorithm with Distributed and Non-Monotone Line Search), an optimization algorithm proposed and developed by Professor K. Schittkowski is implemented.

Relations between important operating variables have been obtained, such as the evolution of the autonomous vehicle’s velocity, the driving torque supplied by the engine and the forces acting on the tires. In a subsequent analysis, the aim is to analyse the relationship between trajectory made and energy consumed and calculate the reduction of greenhouse gas emissions. Also this method has been checked against another different methodology commented on in the references.

The main limitation comes from the modelling that has been done. As greater is the mechanical systems analysed, more simplifying hypotheses should be introduced to solve the corresponding equations with the current computers. However, the solutions are obtained and they can be used qualitatively to draw conclusions.

One main objective is to obtain guidelines to reduce greenhouse gas emissions by reducing energy consumption in the realization of autonomous vehicles’ trajectories. The first step to achieve that is to obtain a good model of the autonomous vehicle that takes into account not only its kinematics but also its dynamic properties, and to propose an optimization process that allows to minimize the energy consumed. In this paper, important relationships between work variables have been obtained.

The idea is to be friendly with nature and the environment. This algorithm can help by reducing an instance of greenhouse gases.

Originality comes from the fact that we not only look for the autonomous vehicle’s modelling, the simulation of its motion and the analysis of its working parameters, but also try to obtain from its working those guidelines that are useful to reduce the energy consumed and the contamination capability of these autonomous vehicles or car-like robots.

The purpose of this study is to apply the Meshless Local Petrov–Galerkin (MLPG) method to solve the bending problems of linear viscoelastic plates, considering Reissner’s theory.

The weak formulation for the set of equations that govern Reissner’s plate theory is implemented in conjunction with the integral formulation applied to viscoelastic constitutive expressions. A meshless method based on the Moving Least Squares (MLS) approximation is considered in the numerical implementation. The final equation system is assembled by adopting simple and efficient schemes for numerical integration, considering a simplified formulation through centralization of the local interpolation domains and Gaussian quadrature at the same field point. The results obtained are compared with available solutions to demonstrate the efficiency of the proposed formulation.

The hereditary integral approach proved to be the most general way to analyze the viscoelastic problem, especially when applied together with the modified scheme for numerical integration. In addition, the variable changing technique is demonstrated to be an efficient formulation for solving shear-locking effects in thin plate problems.

The differential of the present study is related to the manner in which the properties of linear viscoelastic materials are considered in the formulation. Although most authors consider this point through the application of the correspondence principle, the present study works with a hereditary integral formulation. In addition, the variable changing technique is applied to solve the shear-locking effects, and an alternative approximation technique is considered to speed up the numerical integration process.