La vivienda, un problema de acceso al suelo

Indexación: Web of Science; Scielo.Fifty years of continuous development of land squatting seem to indicate the need for new instruments to face the housing deficit. Segregation and urban sprawl are evidences of the importance of land management policies for low-income housing.http://ref.scielo.org/hjkjb

Analyzing the Mass-Rearing System of the California Red Scale Parasitoid Aphytis melinus (Hymenoptera: Aphelinidae)

Results from studies to improve mass rearing production of the parasitoid Aphytis melinus De Bach (Hymenoptera: Aphelinidae) are presented. Parasitoid production was carried out following standard commercial procedures using an alternative host, Aspidiotus nerii Bouché (Hemiptera: Diaspididae), infesting Cucurbita moschata (Duchesne) (Cucurbitaceae), butternut squash. We found that the initial number of A. melinus adults introduced into rearing cages to start production and the scale/parasitoid ratio in those cages profoundly influenced future parasitoid production. We also observed that scale parasitism was positively correlated with the production of parasitoid adults, but this relationship was negatively correlated if > 2.6 parasitoids per d, per cm2, were used in the cages to start parasitism. Supplemental honey (provided on the squash surface) had no clear impact on parasitoid production or survival, but improved host parasitism. Approximately 47% of the host scale population on squash was parasitized, with another 43.1% of the population recorded as dead. We found that ≤ 10 host scales per cm2 on squash was an adequate density for mass production purposes

Research related to vibrations from high speed railway traffic

We discuss here recent results from several research programmes related to dynamic aspects and vibrations induced by high speed railway traffic, developed at the computational mechanics group, within the “Escuela de Ingenieros de Caminos” of the Technical University of Madrid. The first part of this work concerns the dynamic response of railway bridges and structures under high speed traffic. The study of vertical dynamic effects in bridges has lead recently to improved understanding and practical design concepts, embodied in the new engineering codes [1,2,3,4,5]. Some special and seldom considered features of the dynamic response are also discussed. In the second part we present some results for lateral dynamic effects. These have not been so widely studied as the vertical vibrations, however they may pose significant problems for bridges. Finally, in the third part we discuss recent results of ongoing research for the mechanical response of slab track and ballast track, focusing on the vertical vibration of the track and the associated dynamic traffic loads

Renovación de las poblaciones mediante la radicación de allegados: una alternativa a la expansión de Santiago de Chile

Chile, después de 20 años de implementación de una políticafinanciera estable de acceso a la vivienda, es considerado unreferente por los logros alcanzados en la disminución deldéficit habitacional. Pero, ¿a qué costo? Se ha hechovivienda pero no se ha hecho ciudad, la calidad del diseño yde la construcción es deficiente, y la localización esperiférica y segregada. Considerando estos y otros defectos, el Gobierno hareestructurado la política habitacional para impulsarproyectos innovadores de renovación y densificación enáreas urbanas. Haciéndose eco de estos nuevos aires, laFacultad de Arquitectura de la Universidad Católica hadesarrollado proyectos que intentan dar respuesta a lassiguientes interrogantes: ¿Qué ciudad queremos? ¿Quévivienda necesitamos? ¿Cómo se incorpora al beneficiario enel proceso? El proyecto piloto “Renovación de las Poblaciones mediantela Radicación de Allegados” es la validación práctica deaños de experiencia académica en el tema. La estrategiaconsiste en la construcción de una nueva vivienda para losallegados en los lotes donde habitan precariamente, sinnecesidad de adquirir terreno nuevo. Esto permite destinar elmonto total del subsidio a la vivienda aprovechando lasinfraestructuras existentes, y mantener a la población en suscomunas de origen fortaleciendo las redes sociales. Este proyecto generó además un cambio importante en lanormativa que flexibiliza las exigencias de diseño parasegundas viviendas en lotes existentes, lo que supone un granavance del que se podrán beneficiar todos los proyectos dedensificación en poblaciones en el futuro

The ability of residents: the innovative potential for Chilean Housing Policy

Indexación: Web of Science; Scielo.En Chile, la política habitacional y urbana se aparta de las aspiraciones de las familias pobres. Este artículo analiza las acciones que los pobladores emprenden para crear y consolidar su hábitat, especialmente para acceder a suelo y vivienda, y relaciona estas acciones con la política pública. Por medio de estudios de casos, entrevistas a actores clave y revisión bibliográfica, se reconstruye la producción y gestión habitacional de los pobladores a lo largo del tiempo y en el período actual. Se muestra que, en un proceso de largo período, los pobladores han adquirido las competencias para producir la ciudad, y que en ese proceso han tenido un importante papel las mujeres y, más tarde, los jóvenes y los niños. Hasta 1973, las competencias se centran en la producción habitacional y urbana; desde 1990 se centran en la gestión y la labor de los dirigentes de vivienda y barrio se profesionaliza. Se concluye que los pobladores cuentan con todas las competencias para incorporarse a la definición de la política pública junto al gobierno, y que, con esa incorporación, la política habitacional tendría más sentido común y sería más eficiente y los objetivos de proporcionar vivienda se cumplirían de manera más democrática.In Chile, housing and urban policies are out of touch with the aspirations of poor families. This paper analyzes the actions carried out by residents to create and consolidate their habitat, especially when it comes to gaining access to land and housing, and relates these actions to public policies. Through case studies, interviews with key actors and literature review, this contribution reconstructs the production and management of housing by residents over the course of time. This paper shows, on the one hand, that long processes allow residents to acquire the abilities to produce the city. On the other hand, it is also demonstrated the important role of women, young people and children in such processes. Until 1973, these abilities focused on housing and urban production; then, from 1990 onwards, these competences evolved into management-related functions and the role of housing and neighborhood leaders became professionalized. The conclusion is that residents have all the abilities to take part in the framing of public policies along the government. This would enable housing policies to be more approachable, efficient and democratic.http://ref.scielo.org/cqcpy

Proyecto piloto 9x18, una alternativa a la expansión de Santiago

Ponencia que describe el proyecto píloto 9x18 que consiste en la construcción de una nueva vivienda para los allegados en los lotes donde habitan, sin necesidad de adquirir un terreno nuevo

Competência de análise e reflexão sobre a gestão de aulas de livros didáticos por professores estagiários

Research carried out as part of the research project, PID2019-105601GB-I00 / AEI / 10.13039/501100011033 (Ministry of Science and Innovation), with the support of the Research Group FQM-126 (Junta de Andalucía, Spain). The second author could also thank the scholarship and financial support from the University of Costa Rica.Background: Being able to assess what is happening in a teaching-learning process is one of the teacher's competencies. Teachers often must analyse and select the educational resources they consider relevant for their students. Since textbooks are an important tool for instructional design, the teacher must be able to analyse their suitability, identify limitations and make adaptations to overcome them. Objectives: This paper describes the design, implementation, and results of a training action with prospective primary education teachers, aimed at the development of competence for the analysis, identification of conflicts and proposals for the management of textbook lessons, particularly the content of proportionality. Design: The research is interpretative and exploratory, using content analysis to examine the participants' response protocols. Setting and Participants: The experience was carried out in the framework of the Primary Education grade; the sample consisted of 48 students. Data collection and analysis: Data were collected by observer/researcher annotations and participants’ responses to the proposed assessment task. Results: The results show that trainee teachers make progress in identifying conflicts and make suggestions for improvement to increase didactic suitability in the different facets, but that they are not specific enough when describing effective conflict resolution proposals, especially in the epistemic and cognitive facets. Conclusions: For future teachers to become more proficient in the mode of use, it is necessary to reinforce their didactical-mathematical knowledge of proportionality.Antecedentes: Poder valorar lo que ocurre en un proceso de enseñanza- aprendizaje es una de las competencias del profesor. Este debe analizar y seleccionar los recursos educativos que considera pertinentes para sus alumnos. Dado que los libros de texto constituyen un importante recurso para el diseño instruccional, el docente debe ser capaz de analizar su idoneidad, identificar limitaciones y realizar adaptaciones que las solventen. Objetivos: Describimos el diseño, implementación y resultados de una acción formativa con maestros en formación, orientada al desarrollo de la competencia para el análisis, identificación de conflictos y propuestas de gestión de lecciones de libros de texto, particularizadas al contenido de la proporcionalidad. Diseño: La investigación es interpretativa de tipo exploratorio, y se aplica el análisis de contenido para examinar los protocolos de respuesta de los participantes. Lugar y participantes: La experiencia se realizó en el marco del grado de educación primaria; la muestra fue de 48 estudiantes. Recogida y análisis de los datos: La información se recopiló por anotaciones del observador/investigador y las respuestas de los participantes a la tarea de evaluación propuesta. Resultados: Los resultados muestran que los maestros en formación progresan en la identificación de conflictos y que plantean sugerencias de mejora para incrementar la idoneidad didáctica en las distintas facetas, pero que no son suficientemente específicos cuando describen propuestas efectivas de solución a conflictos, especialmente en las facetas epistémica y cognitiva. Conclusiones: Para que los futuros maestros adquieran mayor competencia en el modo de uso, es necesario reforzar sus conocimientos didáctico-matemáticos sobre la proporcionalidad.Contexto: Ser capaz de avaliar o que acontece em um processo de ensino- aprendizagem é uma das competências do professor. Os professores devem analisar e selecionar os recursos educacionais que consideram relevantes para seus alunos. Como os livros didáticos são um recurso importante para o projeto instrucional, o professor deve ser capaz de analisar sua adequação, identificar limitações e fazer adaptações para as ultrapassar. Objetivos: Descrevemos a concepção, implementação e resultados de uma ação de treinamento com professores estagiários, orientada para o desenvolvimento da competência para a análise, identificação de conflitos e propostas para a gestão de lições em livros didáticos, particularmente no que diz respeito ao conteúdo da proporcionalidade. Design: A pesquisa é interpretativa e exploratória, utilizando análise de conteúdo para examinar os protocolos de resposta dos participantes. Ambiente e participantes: A experiência foi realizada no âmbito do grau do ensino primário; a amostra foi de 48 estudantes. Coleta e análise de dados: As informações foram coletadas das notas do observador/pesquisador e das respostas dos participantes à tarefa de avaliação proposta. Resultados: Os resultados mostram que os professores estagiários fazem progressos na identificação de conflitos e fazem sugestões de melhorias para aumentar a adequação didática nas diferentes facetas, mas não são suficientemente específicos ao descrever propostas eficazes de resolução de conflitos, especialmente nas facetas epistêmica e cognitiva. Conclusões: Para que os futuros professores adquiram maior competência no modo de uso, é necessário reforçar seus conhecimentos didático-matemáticos de proporcionalidade.Ministerio de Ciencia e Innovación MICINNUniversidad de Costa Rica UCRJunta de Andalucí

Dynamic effect of high speed railway traffic loads on the ballast track settlement

The traditional ballast track structures are still being used in high speed railways lines with success, however technical problems or performance features have led to non-ballast track solution in some cases. A considerable maintenance work is needed for ballasted tracks due to the track deterioration. Therefore it is very important to understand the mechanism of track deterioration and to predict the track settlement or track irregularity growth rate in order to reduce track maintenance costs and enable new track structures to be designed. The objective of this work is to develop the most adequate and efficient models for calculation of dynamic traffic load effects on railways track infrastructure, and then evaluate the dynamic effect on the ballast track settlement, using a ballast track settlement prediction model, which consists of the vehicle/track dynamic model previously selected and a track settlement law. The calculations are based on dynamic finite element models with direct time integration, contact between wheel and rail and interaction with railway cars. A initial irregularity profile is used in the prediction model. The track settlement law is considered to be a function of number of loading cycles and the magnitude of the loading, which represents the long-term behavior of ballast settlement. The results obtained include the track irregularity growth and the contact force in the final interaction of numerical simulatio

Solving some special cases of monomial ratio equations appearing frequently in physical and engineering problems

We first show that monomial ratio equations are not only very common in Physics and Engineering, but the natural type of equations in many practical problems. More precisely, in the case of models involving scale variables if the used formulas are not of this type they are not physically valid. The consequence is that when estimating the model parameters we are faced with systems of monomial ratio equations that are nonlinear and difficult to solve. In this paper, we provide an original algorithm to obtain the unique solutions of systems of equations made of linear combinations of monomial ratios whose coefficient matrix has a proper null space with low dimension that permits solving the problem in a simple way. Finally, we illustrate the proposed methods by their application to two practical problems from the hydraulic and structural fields.Peer ReviewedPostprint (published version

Collection and integration of local knowledge and experience through a collective spatial analysis

This article discusses the convenience of adopting an approach of Collective Spatial Analysis in the P/PGIS processes, with the aim of improving the collection and integration of knowledge and local expertise in decision-making, mainly in the fields of planning and adopting territorial policies. Based on empirical evidence, as a result of the review of scientific articles from the Web of Science database, in which it is displayed how the knowledge and experience of people involved in decision-making supported by P/PGIS are collected and used, a prototype of a WEB-GSDSS application has been developed. This prototype allows a group of people to participate anonymously, in an asynchronous and distributed way, in a decision-making process to locate goods, services, or events through the convergence of their views. Via this application, two case studies for planning services in districts of Ecuador and Italy were carried out. Early results suggest that in P/PGIS local and external actors contribute their knowledge and experience to generate information that afterwards is integrated and analysed in the decision-making process. On the other hand, in a Collective Spatial Analysis, these actors analyse and generate information in conjunction with their knowledge and experience during the process of decision-making. We conclude that, although the Collective Spatial Analysis approach presented is in a subjective and initial stage, it does drive improvements in the collection and integration of knowledge and local experience, foremost among them is an interdisciplinary geo-consensusPeer ReviewedPostprint (published version