DETERMINANTS SPATIAUX ET SOCIAUX DE LA MOBILITE DOMICILE-TRAVAIL DANS 13 AIRES URBAINES FRANÇAISES : UNE APPROCHE PAR LA FORME URBAINE, A DEUX ECHELLES GEOGRAPHIQUES

http://asrdlf2011.com/Les liens entre forme urbaine, au sens de l'organisation dans l'espace intra-urbain des localisations (actifs et emplois), et pratiques de mobilité quotidienne, en particulier les migrations domicile-travail, font l'objet d'une attention soutenue ces dernières décennies et admet principalement deux catégories de travaux. D'un côté, on trouve des recherches qui discutent l'influence des caractéristiques de l'espace de résidence sur la mobilité des habitants de cet espace, appréciant la forme urbaine à une échelle locale, infra-urbaine. D'un autre côté, des recherches, nettement moins nombreuses, posent la question des liens entre la forme urbaine qualifiée à l'échelle de la ville tout entière, et la mobilité. L'originalité de cette proposition de communication réside dans l'utilisation simultanée d'indicateurs de forme urbaine et d'indicateurs socio-économiques aux niveaux local (la commune) et métropolitain (l'aire urbaine) en complément d'indicateurs socio-économiques classiques (comme le revenu), pour appréhender la variabilité des comportements de mobilité domicile-travail dans treize aires urbaines françaises de plus de 500 000 habitants (en 1999), Paris exclu. Notre objectif est de montrer et de hiérarchiser l'influence des différents indicateurs considérés

Ab-initio vibrational properties of transition metal chalcopyrite alloys determined as high-efficiency intermediate-band photovoltaic materials

In this work, we present frozen phonon and linear response ab-initio research into the vibrational properties of the CuGaS2 chalcopyrite and transition metal substituted (CuGaS2)M alloys. These systems are potential candidates for developing a novel solar-cell material with enhanced optoelectronic properties based in the implementation of the intermediate-band concept. We have previously carried out ab-initio calculations of the electronic properties of these kinds of chalcopyrite metal alloys showing a narrow transition metal band isolated in the semiconductor band gap. The substitutes used in the present work are the 3d metal elements, Titanium and Chromium. For the theoretical calculations we use standard density functional theory at local density and generalized gradient approximation levels. We found that the optical phonon branches of the transition metal chalcopyrite, are very sensitive to the specific bonding geometry and small changes in the transition metal environment

Optimization-oriented RAW modeling of IEEE 802.11ah heterogeneous networks

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The new medium access method of IEEE 802.11ah, called Restricted Access Window (RAW), divides stations into different groups, and only allows stations in the same group to access the channel simultaneously, in order to reduce collisions and thus achieve better performance (e.g., throughput). However, the existing station grouping strategies only support homogeneous scenarios where all stations use the same modulation and coding scheme (MCS) and packet size. A surrogate model is an efficient mathematical model that represents the behavior of a complex system, trained with a limited set of labeled input-output data samples. In this paper, we present a surrogate model that can accurately predict RAW performance under a given Restricted Access Window (RAW) configuration in heterogeneous networks. Different from the homogeneous scenario, heterogeneous networks are defined by a large number of parameters, leading to an enormous design space, i.e., the order of 1017 possible data points. This is too big to achieve feasible training convergence. In this paper, we present a novel training methodology that leads to a new design space with highly reduced size, i.e., the order of 105 data points. The surrogate model converges when less than 6000 labeled data points are used for training, which is only a tiny portion of the whole design space. The results show that, the relative error between model prediction and simulation results is less than 0.1 for 95% of the data points, in the areas of the design space studied. Its low complexity and high precision make the proposed model a valuable tool to develop real-time RAW optimization algorithms for heterogeneous IEEE 802.11ah networks.Postprint (author's final draft

A Novel Fault Detection and Fault Location Method for VSC-HVDC Links Based on Gap Frequency Spectrum Analysis

This paper proposes a one-end gap-based fault location method for VSC-HVDC transmission line using the fault current signal. Using the post-fault current time series, the frequency spectrum is generated for measuring the gaps between the contiguous peak frequencies. This method is able to locate the fault by analyzing the single-end fault current, which guarantees a faster response than using two-end data. The new gap-based approach is able to give accurate fault detection using any appropriate range of post-fault signal. Furthermore, the proposed method is fault resistance independent. A two-terminal VSC-HVDC system is modeled in PSCAD/EMTDC. The algorithm is verified by studying different cases of different fault resistances in various fault locations. The result shows that the proposed method gives an accurate and reliable fault location detection along DC transmission line. In addition, the proposed algorithm can be potentially used in other HVDC systems

Empoderamento da mulher Kaiowa e Guarani na luta pelo reconhecimento dos direitos indígenas e identidade étnico-cultural

Este artigo aborda as liderançasfemininasKaiowá e Guarani, suaspráticas e os motivos relatados por elas, naluta de resistência pelos direitos e conquista de maiorautonomia de gênero e de suas comunidades, no contexto em que se insere a Reserva Indígena de Dourados, no Mato Grosso do Sul / Brasil. O objetivo foi realizar umestudo etnográfico junto a essasmulheres indígenas, para interpretar por meio de suapercepções, os níveis de poder, que se tornaram foco dessasestratégias de lutafeminina. As informaçõesforamobtidas de fontes secundarias e primárias (entrevista semiestruturada, questionário), mediante umaanálisequali-quantitativa. O movimento feminista Kaiowaì e Guaranimanifesta-se emquatroníveis de empoderamento: (1) do indivíduo (2) da família (3) da comunidade (4) da sociedade, emboraaindahajamuitasdificuldades a serem superadasEste artículo aborda el liderazgo femenino Kaiowá y Guarani, sus prácticas y las motivaciones evocadas por ellas, en la lucha de resistencia por los derechos y conquista de mayor autonomía de género y de sus comunidades, en el contexto en que se encuentra la Reserva Indígena de Dourados, en Mato Grosso del Sur / Brasil. El objetivo fue realizar un estudio etnográfico a estas mujeres, para interpretar por medio de su percepción, los niveles de poder, que se convirtieron en foco de esas estrategias de lucha femenina. La información se obtuvo de fuentes secundarias y primarias (entrevista semiestructurada, cuestionario), mediante un análisis cualitativo cuantitativo. El movimiento de mujeres Kaiowá y Guarani se manifiesta en cuatro niveles de empoderamiento: (1) del individuo (2) de la familia (3) de la comunidad (4) de la sociedad, aunque todavía hay muchas dificultades a superar.This article addresses the female leadership Kaiowá and Guarani, their practices and the motivations evoked by them, in the struggle for rights and conquest of greater autonomy of gender and their communities, in the context of the Dourados Indigenous Reserve, in Mato Grosso do Sul / Brazil. The objective was to carry out an ethnographic study of these women in order to interpret, through their perception, the levels of power that became the focus of these strategies of female struggle. The information was obtained from secondary and primary sources (semi-structured interview, questionnaire), through a quantitative qualitative analysis. The Kaiowáand Guarani women’s movement is expressed in four levels of empowerment: (1) of the individual (2) of the family (3) of the community (4) of the society, although there are still many difficulties to overcome

Stag hunt game-based approach for cooperative UAVs

Unmanned aerial vehicles (UAVs) are being employed in many areas such as photography, emergency, entertainment, defence, agriculture, forestry, mining and construction. Over the last decade, UAV technology hasfound applicationsin numerous construction project phases, ranging from site mapping, progress monitoring, building inspection, damage assessments, and material delivery. While extensive studies have been conducted on the advantages of UAVs for various construction-related processes, studies on UAV collaboration to improve the task capacity and efficiency are still scarce. This paper proposes a new cooperative path planning algorithm for multiple UAVs based on the stag hunt game and particle swarm optimization (PSO). First, a cost function for each UAV is defined, incorporating multiple objectives and constraints. The UAV game framework is then developed to formulate the multi-UAV path planning into the problem of finding payoff-dominant e quilibrium. Next, a PSO-based algorithm is proposed to obtain optimal paths for the UAVs. Simulation results for a large construction site inspected by three UAVs indicate the effectiveness of the proposed algorithm in generating feasible and efficient flight paths for UAV formation during the inspection task

A New Web-stepwise Solver for Ordinary Differential Equations

In this paper we introduce SODES (Step-wise Ordinary Differential Equations Solver) which is a new solver for Ordinary Dfferential Equations (ODE). SODES can be used not only as a solver but also as a tutorial for the teaching and learning process of ODE, since it provides the solution displaying all the the steps needed to obtain it. In [1] we introduced SFOPDES (Step-wise First Order Partial Differential Equations Solver) developed in Derive, a Computer Algebra System (CAS). Two of the future works related considered in [1] were the development of new step-wise solvers for different math topics and the use of other CAS and programming with Python. This way, it is possible to develop web applications, freely available, providing different step-wise solvers. In this sense, SODES is the first work related with both ideas. Therefore, SODES is a web solver for ODE, developed in Python (using its CAS module SymPy). SODES increases the types of ODE that SFOPDES can deal with. Specifically, it provides, step by step, the solution of the following types of ODE: 1. First-order ODE: separable equations and equations reducible to them, homogeneous equations and equations reducible to them, exact differential equations and equations reducible to them (integrating factor technique), linear equations, the Bernoulli equation, the Riccati equation, First-order differential equations and nth degree in y', Generic programs to solve first order differential equations. 2. Higher-order ODE: higher order linear equations with constant coefficients. As a final remark, actually, SODES can be used in English, French or Spanish, but it can be easily extendable to other languages.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

SODES: Solving ordinary differential equations step by step

In this paper, we introduce SODES (Stepwise Ordinary Differential Equations Solver) a new solver for Ordinary Differential Equations (ODE). SODES can optionally provide the solution displaying all the steps needed to obtain it. This way, SODES is an important tool not only for researchers who need solving ODE but also constitutes an important tool for the teaching and learning process of ODE. SODES has been developed using programming with a Computer Algebra System (CAS). Specifically, we use the CAS Derive but it can be easily adapted to any other CAS supporting programming. SODES provides, step by step, the solution of the following types of ODE: separable, homogeneous, exact, integrating factors, linear, Bernoulli, Riccati, first order ODE of nth degree, Cauchy’s problems of first order ODE, higher order linear homogeneous equations with constant coefficients, Lagrange’s method for particular solutions of higher order linear equations with constant coefficients, higher order linear equations with constant coefficients and Cauchy’s problems of higher order linear equations with constant coefficients. SODES also deals with two generic programs which determine the type or types of a given ODE and provides the solution. In this paper we will also introduce a draft of a Graphical User Interface (GUI) for SODES in a local web application using programming in Python (using its CAS module SymPy) which is a more portable and free CAS. This draft can be used in English, French and Spanish, and can be easily extended to other languages. The code of SODES and the GUI are freely available so that it can be used by users who also will be able to adapt it to their needsFunding for open access charge: Universidad de Málaga / CBU