1,751 research outputs found
Descentralisation, Integration and polycentrism in Barcelona
In this study the employment subcentres of the Metropolitan Region of Barcelona are identified using different criteria. Once catalogued according to their nature,i.e. subcentres arising from integration and decentralisation, they are analysed to see whether their impact on population density depends on their origin. The results obtained confirm a greater impact of integrated subcentres in comparison with decentralised ones, amplified in turn by the fact that the former are further from the CBD and present a greater degree of self-containment in the labor market.Employment decentralisation, policentric city, metropolitan integration
Urban spatial structure and suburbanisation. The case of the Barcelona Metropolitan
The metropolitan spatial structure displays various patterns, sometimes monocentricity and sometimes multicentricity, which seems much more complicated than the exponential density function used in classic works such as Clark (1961), Muth (1969) or Mills (1973) among others, can effectively represent. It seems that a more flexible density function,such as cubic spline function (Anderson (1982), Zheng (1991), etc.) to describe the density-accessibility relationship is needed. Also, accessibility, the fundamental determinant of density variations, is only partly captured by the inclusion of distance to the city centre as an explanatory variable. Steen (1986) has proposed to correct that miss-especification by including an additional gradient for distance to the nearest transportation axis. In identifying the determinants of urban spatial structure in the context of inter-urban systems, some of the variables proposed by Muth (1969), Mills (1973) and Alperovich (1983) such as city age or population, make no sense in the case of a single urban system. All three criticism to the exponential density function and its determinants apply for the Barcelona Metropolitan Region, a polycentric conurbation structured on well defined transportation axes.Suburbanisation, decentralisation, Barcelona
Cubic spline population density functions and subcentre delimitation. The case of Barcelona
The presence of subcentres cannot be captured by an exponential function. Cubic spline functions seem more appropriate to depict the polycentricity pattern of modern urban systems. Using data from Barcelona Metropolitan Region, two possible population subcentre delimitation procedures are discussed. One, taking an estimated derivative equal to zero, the other, a density gradient equal to zero. It is argued that, in using a cubic spline function, a delimitation strategy based on derivatives is more appropriate than one based on gradients because the estimated density can be negative in sections with very low densities and few observations, leading to sudden changes in estimated gradients. It is also argued that using as a criteria for subcentre delimitation a second derivative with value zero allow us to capture a more restricted subcentre area than using as a criteria a first derivative zero. This methodology can also be used for intermediate ring delimitation.polycentrism, cubic spline functions
Gobernanza y crecimiento econĂłmico
Recientemente, se ha venido concediendo una gran importancia al papel que desempeña la gobernanza en el ĂĄmbito econĂłmico. En tĂ©rminos generales se suele señalar que la forma en la que se gobiernen las instituciones afecta en gran medida a la actividad econĂłmica. Ello ha llevado a que se plantee la polĂ©mica de elegir entre el mercado y las instituciones a la hora de alcanzar los objetivos de polĂtica econĂłmica. La elecciĂłn de uno u otras dependerĂĄ de la eficiencia que muestren a la hora de alcanzar dichos objetivos. Para ver dicha eficacia exponemos un ejemplo empĂrico de la relaciĂłn entre gobernanza y crecimiento econĂłmico para el caso de algunos paĂses europeos._________________________________Recently, great relevance is granted to the governance role in the economic
activity. In general terms it is shown that the way in which institutions govern
has relevant effects on economic activity. For this reason the controversy
between market and institutions to achieve the economic policy objectives is
considered. The choice of the former or the later will depend on the efficiency
that they show in the achievement of such objectives. To consider that efficiency,
an empirical example of the relationship between governance and economic
growth is developed for the case of some European countries
Diseño de fåbrica ladrillera potencializando procesos productivos, ambiente laboral e impacto medioambiental
Es habitual en los arquitectos el desarrollo de espacios habitables y urbanĂsticos, pero pocas veces tenemos la oportunidad de involucrar no solo al usuario sino procesos productivos en la arquitectura que se diseña. Parte importante de la creaciĂłn del trabajo de grado es resolver problemas en el contexto Colombiano y hacerlo mediante aportes novedosos y significativos que den soluciĂłn de estos problemas. El tema de este trabajo de grado intenta responder el problema en el deterioro medio ambiental y el desarrollo sostenible enfocado en espacios industriales. Puesto que las industrias son espacios que muchas veces solo son pensados para el resguardo de equipos y maquinarias olvidando en ocasiones el potencial de la capacidad productiva gracias a un espacio idĂłneo, el confort para el recurso humano de la industria y el impacto de sus procesos en el medio ambiente. Una de las industrias con mĂĄs conflictos medioambientales en nuestro paĂs es la industria ladrillera. Los procesos de fabricaciĂłn de ladrillo pasan por varias etapas y en cada una se ve relacionado algĂșn tipo de labor que tiene un impacto en el entorno. Lo que se lograra evidenciar en este trabajo de grado es la respuesta desde el diseño arquitectĂłnico a esta problemĂĄtica medio ambiental. Ideas como el aprovechamiento energĂ©tico de los procesos productivos y la recuperaciĂłn de recursos energĂ©ticos e hĂdricos mediante tecnologĂas apropiadas implantadas en el proyecto son la intenciĂłn para que junto a un correcto manejo espacial de la planta industrial, se llegue a un modelo arquitectĂłnico industrial amigable con el entorno y eficientemente productivo.Architects working on the development of residential and urban spaces, but rarely have the opportunity to involve not only the user but production processes in architecture that is designed. An important part of the creation of the thesis is to solve problems in the Colombian context and make it through innovative and significant contributions that provide solutions to these problems. The theme of this work tries to answer the problem degree in environmental degradation and sustainable development focusing on industrial spaces. Since industries are spaces that are often only intended to guard equipment and machinery forgetting sometimes the potential productive capacity thanks to a suitable space, comfort for the human resource industry and the impact of their processes environment. One of the industries most environmental conflicts in our country is the brick industry. The brick manufacturing processes go through several stages and each is related some kind of work that has an impact on the environment. What was achieved in this work demonstrate grade is the answer from architectural design to this environmental problem. Ideas such as energy efficiency of production processes and the recovery of energy and water resources through appropriate technologies implemented in the project are intended to with proper spatial management of the plant, a friendly industrial architectural model is reached with the efficient and productive environment.Arquitecto (a)Pregrad
Efecto del aumento de temperatura sobre hongos en suelos de pastizal y bosque alto andino Mundo Nuevo, Cundinamarca
Se diseñó un experimento en campo con condiciones controladas, en donde se establecieron nueve dispositivos para elevar la temperatura 1°C tanto en bosque altoandino como en pastizal para ganaderĂa. DespuĂ©s de 17 meses de instalados los dispositivos se realizaron dos muestreos separados por un periodo de dos meses, en donde se tomaron muestras de suelo y se registrĂł la temperatura en campo dentro y fuera de los dispositivos. Las muestras se procesaron en el laboratorio para cuantificar la densidad y la riqueza de hongos antagonistas, usando el mĂ©todo de diluciones seriadas y siembra en placa profunda en diferentes medios de cultivo. Adicionalmente se realizaron pruebas fisicoquĂmicas del suelo para correlacionarlas con la densidad y riqueza de estos hongos. La determinaciĂłn del efecto de la temperatura sobre la densidad y riqueza de los hongos se realizĂł con una regresiĂłn, y adicionalmente un anĂĄlisis de varianza factorial para observar las posibles diferencias entre, dentro y fuera del dispositivo con un nivel de significancia de 0,05. No se encontraron diferencias significativas entre dentro y fuera del dispositivo en la densidad y riqueza de hongos en ambos usos de suelo, tampoco se encontrĂł una relaciĂłn entre las variables fisicoquĂmicas del suelo, y la densidad y riqueza de hongos. Se encontrĂł una mayor densidad de hongos en bosque altoandino, y una mayor riqueza en pastizal.an experiment in controlled field conditions, where nine devices were set to raise the temperature by 1 ° C in both high Andean forest and pasture for livestock was designed. After 17 months of two separate devices installed for a period of two months where soil samples were taken and the temperature was recorded in field inside and outside devices samples were taken. The samples were processed in the laboratory to measure the density and richness of antagonistic fungi, using the method of serial dilutions and seeding in deep plate in different culture media. Additionally physicochemical soil tests to correlate with the density and richness of these fungi were performed. Determining the effect of temperature on the density and richness of fungi he was performed with a regression, and additionally a factorial analysis of variance to observe possible differences between inside and outside of the device with a significance level of 0.05. No significant differences between inside and outside the device in the density and richness of fungi in both land use were found, either a relation between soil physicochemical variables, and the density and richness of fungi was found. a higher density of fungi in high Andean forest and grassland greater wealth found.BiĂłlogo (a)Pregrad
Studentsâ perceptions about using anime and manga as an audiovisual tool to practice Japanese as a foreign language
"Japanese as a Foreign Language (JFL) has increased its fans around the world since anime and manga are considered some of the most relevant components in Japanese pop culture. In fact, there exists a necessity for Japanese learners and teachers to find a way to practice and improve their learning process of this foreign language in Mexico. Different researchers have contributed to analyze Anime and Manga importance in aspects such as motivation or skill improvements when teaching JFL. Therefore, the purpose for this research is to analyze the students' perceptions of a public university in central Mexico towards the use of anime and manga as an audiovisual tool to learn JFL. This study used the data from answered questionnaires provided by seven Japanese as a Foreign Language learners in this public university. The results obtained from the questionnaire prove that anime and manga are suitable learning materials to practice JFL inside and outside the classroom "
Continuous vs. discrete models for the quantum harmonic oscillator and the hydrogen atom
The Kravchuk and Meixner polynomials of discrete variable are introduced for
the discrete models of the harmonic oscillator and hydrogen atom. Starting from
Rodrigues formula we construct raising and lowering operators, commutation and
anticommutation relations. The physical properties of discrete models are
figured out through the equivalence with the continuous models obtained by
limit process.Comment: LaTeX, 14 pages (late submission
El consumo de energĂa y la economĂa mexicana. un anĂĄlisis empĂrico con VAR
The main objective of this study is to analyze the relationships between consumption of energy, output, relative prices of energy and employment in Mexico over the period 1965-2001. The main results indicate that there is at least one cointegrating vector implying one longterm stable relationship between energy consumption, output, relative prices and employment. This cointegrating vector, which was obtained by the Johansen (1988) procedure and corrected for possible structural changes using the method proposed by Hansen and Johansen (1993), has coefficients that can be interpreted according to the economic theory as a demand function and that suggest energy and employment are substitute goods. The weak exogeneity tests show the existence of a close relationship between consumption of energy and output, meanwhile the relative prices and employment are weak exogenous. The Granger non-causality tests indicate a bi-directional relationship between the changes of output and energy consumption and the presence of a complex feedback process between all the variables included in the analysis that must be considered in order to design an energy control public policy. In this sense, the simultaneous movements among energy, income and employment suggest that any energy control policy might also influence the trajectory of output and employment.energy, output, employment, causality
On the computational efficiency and implementation of block-iterative algorithms for nonlinear coupled Problems
Outlines a general methodology for the solution of the system of algebraic equations arising from the discretization of the field equations governing coupled problems. Considers that this discrete problem is obtained from the finite element discretization in space and the finite difference discretization in time. Aims to preserve software modularity, to be able to use existing single field codes to solve more complex problems, and to exploit computer resources optimally, emulating parallel processing. To this end, deals with two well-known coupled problems of computational mechanics – the fluid-structure interaction problem and thermally-driven flows of incompressible fluids. Demonstrates the possibility of coupling the block-iterative loop with the nonlinearity of the problems through numerical experiments which suggest that even a mild nonlinearity drives the convergence rate of the complete iterative scheme, at least for the two problems considered here. Discusses the implementation of this alternative to the direct coupled solution, stating advantages and disadvantages. Explains also the need for online synchronized communication between the different codes used as is the description of the master code which will control the overall algorithm
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