A New Materials and Design Approach for Roads, Bridges, Pavement, and Concrete

Increased understanding of demand for transport energy and how to improve road pavement materials would enable decision makers to make environmental, financial, and other positive changes in future planning and design of roads, bridges, and other important transportation structures. This research comprises three studies focused on pavement materials and a fourth study that examines energy demand within the road transportation sector. These studies are as follows: 1. A techno-economic study of ground tire rubber as an asphalt modifier; 2. A computational fluid dynamics analysis comparing the urban heat island effect of two different pavement materials – asphalt and Portland Cement Concrete; 3. A new approach that modifies the surface of ground tire rubber using low-cost chemicals and treatment methods to be used in asphalt applications; and 4. Analysis of road transport energy demand in California and the United States. The findings of these studies include that 1. GTR is an effective and economically suitable additive for modified asphalt, 2. the suitability of PCC pavements in urban settings should be reexamined, 3. Surface modification of GTR materials can improve compatibilization of particles for the manufacture of asphalt materials, and 4. gasoline sales are generally price inelastic in both the U.S. and California. Ultimately, these four studies improve understanding of road pavement materials and transport energy demand. They lay out important information about the future of the relationship between materials and design in the transportation industry. These findings may be used by engineers, policymakers, and others in the industry to better consider implications of decisions involved in design, creation, and modification of structures using pavement and concrete, including roads, bridges, etc

El centro histórico de Morelia: gestión social y revaloración del patrimonio

The historic center of Morelia is one of the most stately and best conserved in México, so much so that in 1991 it was declared a Patrimony of Humanity site by UNESCO. Notwithstanding such a mark of distinction, the last 25 years have seen the center invaded by a proliferation of street vendors, a problem that until recently seemed insoluable. It generated not only social and environmental problems but also limited the enjoyment to the public spaces by residents and tourists alike. Thanks to consensual political action and multiple negotiations, the more than 1.500 vendors were removed and relocated in more appropriate locations, leaving the city center to better exhibit its pleasant environment and distinguished architectural past. The paper documents the methods uses in relocation process, especially the role played by the Patronato Pro-Rescate del Centro Histórico to achieve this important objective which, for Mexico, appears most encouraging and has generated a climate of optimism.El centro histórico de Morelia es uno de los más señoriales y mejor conservados de México e incluso en 1991 fue declarado Patrimonio de la Humanidad por parte de la UNESCO. No obstante, la proliferación de comercio informal en las calles y plazas observado durante los últimos 25 años se convirtió en un problema que parecía irresoluble y que generaba problemas sociales y ambientales, además de que limitaba el disfrute de los espacios públicos, tanto para los ciudadanos locales como para el turismo. Gracias a una labor de consenso político y de múltiples negociaciones se logró retirar a dichos comerciantes (más de 1.500) mismos que fueron realojados en sitios mejor dispuestos con lo cual el centro histórico luce una agradable imagen y se encuentra en mejores condiciones para perpetuar su centralidad. Se documentan los mecanismos utilizados y el papel desarrollado por el Patronato Pro-Rescate del Centro Histórico para alcanzar este importante objetivo que en México resulta muy alentador y ha generado un clima de optimismo social

An experiment on Nash implementation

We perform an experimental test of Maskin's canonical mechanism for Nash implementation, using 3 subjects in non-repeated groups, as well as 3 outcomes, states of nature, and integer choices. We find that this mechanism succesfully implements the desired outcome a large majority of the time and an imbedded comprehension test indicates that subjects were generally able to comprehend their decision tasks. The performance can also be improved by imposing a fine on non designated dissidents. We offer some explanations for the imperfect implementation, including risk preferences, the possibilities that agents have for collusion, and the mixed strategy equilibria of the game.Implementation, experiments, mechanisms, Leex

Analytical and numerical solutions of the potential and electric field generated by different electrode arrays in a tumor tissue under electrotherapy

<p>Abstract</p> <p>Background</p> <p>Electrotherapy is a relatively well established and efficient method of tumor treatment. In this paper we focus on analytical and numerical calculations of the potential and electric field distributions inside a tumor tissue in a two-dimensional model (2D-model) generated by means of electrode arrays with shapes of different conic sections (ellipse, parabola and hyperbola).</p> <p>Methods</p> <p>Analytical calculations of the potential and electric field distributions based on 2D-models for different electrode arrays are performed by solving the Laplace equation, meanwhile the numerical solution is solved by means of finite element method in two dimensions.</p> <p>Results</p> <p>Both analytical and numerical solutions reveal significant differences between the electric field distributions generated by electrode arrays with shapes of circle and different conic sections (elliptic, parabolic and hyperbolic). Electrode arrays with circular, elliptical and hyperbolic shapes have the advantage of concentrating the electric field lines in the tumor.</p> <p>Conclusion</p> <p>The mathematical approach presented in this study provides a useful tool for the design of electrode arrays with different shapes of conic sections by means of the use of the unifying principle. At the same time, we verify the good correspondence between the analytical and numerical solutions for the potential and electric field distributions generated by the electrode array with different conic sections.</p

Paisaje industrial y sus representaciones: La fábrica "La Parisiense" de Guadalajara durante el Porfiriato

Se presenta un estudio histórico consistente en la deconstrucción de imágenes fotográficas y pictóricas de un paisaje industrial inserto en Guadalajara, la fábrica de jabones y perfumes La Parisiense, fundada en 1892. &nbsp;Tales representaciones, al igual que muchas otras, se utilizaron como vehículo de socialización y legitimación del régimen de Porfirio Díaz Mori, quien gobernó México durante el período 1877-1911. &nbsp;El tendido de una amplia red ferroviaria configuró nuevas articulaciones territoriales e impulsó el desarrollo industrial. Las lecturas reales y simbólicas del pasado se enlazan con una mirada actual del vestigio industrial de La Parisiense el cual afronta un doble embate, la degradación física y el olvido social, de ahí que la valorización del patrimonio cultural encuentre un aliado en el poder de las imágenes. &nbsp;Este é um estudo histórico que consiste na desconstrução de imagens fotográficas e pictóricas de uma paisagem industrial localizada em Guadalajara, a fábrica de sabonetes e perfumes La Parisiense, fundada em 1892.&nbsp; Tais representações, como muitas outras, foram utilizadas como veículo de socialização e legitimação do regime de Porfirio Díaz Mori, o qual governou o México durante o período 1877-1911.&nbsp; O estabelecimento de uma ampla rede ferroviária configurou novas articulações e impulsionou o desenvolvimento industrial. As leituras reais e simbólicas do passado se envolvem com um olhar atual do vestígio industrial de La Parisiense, o qual coloca um duplo embate: a degradação física e o esquecimento social. Isso sugere que a valorização do patrimônio cultural encontre um aliado no poder das imagens. &nbsp

Jerusalen a la vista: retrato verbal por tres mexicanos decimonónicos

Los relatos de los viajeros del siglo XIX constituyen una fuente valiosa yhasta ahora poco apreciada. Pueden ser objeto de análisis literario desde múltiplesperspectivas. Como fuente histórica son un acervo proclive a convertirse en un objeto de estudio en si mismo o a complementar otro tipo de fuentes documentales y así enriquecer visiones cualitativas imposibles de obtener por otras vías. Esas fotografías verbales son oro molido para los geógrafos desde el momento que se convierten en un testimonio útil para alimentar uno de los conceptos más fértiles y creativos de nuestra disciplina: el paisaje

Utilización de las tecnologías de la información y la comunicación (TIC) en los procesos de marketing en las empresas colombianas

Este artículo se propone comentar cómo se ha dado la incorporación de las TIC a las empresas, de una manera integral. Para ello, en primer lugar, se señalan los cambios estructurales que han tenido que incorporar aquellas empresas que desean progresar en este mundo globalizado y estar a la vanguardia en el uso de la tecnología. En un segundo momento, se analiza a la compañía desde el área encargada de la promoción, publicidad y ventas de sus productos. Finalmente, se contextualiza el tema en el entorno colombiano y se presenta un diagnóstico acerca del uso apropiado de las TIC en las empresas colombianas, con respecto a la comercialización y venta de los productos que ofrecen. Se pretende así responder a la pregunta ¿En qué medida han incorporado las empresas colombianas las TIC en sus procesos de mercadeo y qué tanto han evolucionado con respecto al panorama internacional?Incluye bibliografí