http://hdl.handle.net/2117/576 Sat, 18 May 2013 08:27:49 GMT 2013-05-18T08:27:49Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/19236 Title: Working in the city: The knowledge city, experience from Barcelona's Metropolitan Centre Authors: Marmolejo Duarte, Carlos Ramiro Wed, 15 May 2013 10:19:43 GMT http://hdl.handle.net/2117/19236 2013-05-15T10:19:43Z Marmolejo Duarte, Carlos Ramiro no http://hdl.handle.net/2117/19205 Title: L'Emigració de Barcelona: Causes i característiques. El mercat de l'habitatge com a factor incentivador de l'emigració Authors: Garcia-Almirall, M. Pilar Tue, 14 May 2013 12:02:09 GMT http://hdl.handle.net/2117/19205 2013-05-14T12:02:09Z Garcia-Almirall, M. Pilar no http://hdl.handle.net/2117/19197 Title: Reactions of fly ash with calcium aluminate cement and calcium sulphate Authors: Fernández Carrasco, Lucía; Vázquez Ramonich, Enric Abstract: The hydration processes in the ternary system fly ash/calcium aluminate cement/calcium sulphate (FA/CAC/C$) at 20 °C were investigated; six compositions from the ternary system FA/CAC/C$ were selected for this study. The nature of the reaction products in these pastes were analysed by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). At four days reaction time, the main hydration reaction product in these pastes was ettringite and the samples with major initial CAC presented minor ettringite but calcium aluminates hydrates. The amount of ettringite developed in the systems has no direct relation with the initial components. Tue, 14 May 2013 10:28:31 GMT http://hdl.handle.net/2117/19197 2013-05-14T10:28:31Z Fernández Carrasco, Lucía; Vázquez Ramonich, Enric no The hydration processes in the ternary system fly ash/calcium aluminate cement/calcium sulphate (FA/CAC/C$) at 20 °C were investigated; six compositions from the ternary system FA/CAC/C$ were selected for this study. The nature of the reaction products in these pastes were analysed by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). At four days reaction time, the main hydration reaction product in these pastes was ettringite and the samples with major initial CAC presented minor ettringite but calcium aluminates hydrates. The amount of ettringite developed in the systems has no direct relation with the initial components. http://hdl.handle.net/2117/19196 Title: Carbonation of ternary building cementing materials Authors: Fernández Carrasco, Lucía; Torrens Martín, David; Martínez Ramírez, Sagrario Abstract: The carbonation processes of ettringite and calcium aluminate hydrates phases developed by hydration of calcium aluminate cement, fly ash and calcium sulphate ternary mixtures have been studied. The hydrated samples were submitted to 4% of CO2 in a carbonation chamber, and were analysed, previous carbonation and after 14 and 90 days of carbonation time, by infrared spectroscopy and X-ray diffraction; the developed morphology was performed with the 14 days carbonated samples. The results evidenced that ettringite reacts with CO2 after 14 days of exposition time and evolves totally at 90 days; the developed hydrated phases C3AH6 in samples with major CAC content, also reacts with CO2. Due to carbonation, calcium carbonate – mainly vaterite but also aragonite-, depending on the initial formulation, aluminium hydroxide and gypsum were detected. Tue, 14 May 2013 10:07:32 GMT http://hdl.handle.net/2117/19196 2013-05-14T10:07:32Z Fernández Carrasco, Lucía; Torrens Martín, David; Martínez Ramírez, Sagrario no CAC, Calcium sulphate, Carbonation, Ettringite, Fly ash The carbonation processes of ettringite and calcium aluminate hydrates phases developed by hydration of calcium aluminate cement, fly ash and calcium sulphate ternary mixtures have been studied. The hydrated samples were submitted to 4% of CO2 in a carbonation chamber, and were analysed, previous carbonation and after 14 and 90 days of carbonation time, by infrared spectroscopy and X-ray diffraction; the developed morphology was performed with the 14 days carbonated samples. The results evidenced that ettringite reacts with CO2 after 14 days of exposition time and evolves totally at 90 days; the developed hydrated phases C3AH6 in samples with major CAC content, also reacts with CO2. Due to carbonation, calcium carbonate – mainly vaterite but also aragonite-, depending on the initial formulation, aluminium hydroxide and gypsum were detected. http://hdl.handle.net/2117/19189 Title: Supercritical Carbonation of Calcium Aluminate Cement Authors: Fernández Carrasco, Lucía; Miravitlles, C; Rius, J. Abstract: The microstructural changes occurring during supercritical carbonation (scCO2) of calcium aluminate cement (CAC) and changes to its strength have been investigated. Cylindrical specimens of CAC cured at different temperatures were prepared and then subjected to scCO2. It is shown that CAC carbonation in supercritical conditions is accelerated with a positive effect on the compressive strength. Due to the scCO2 treatment, both conversion and alkaline hydrolysis are avoided. The best behaviour of the studied specimens was attained for samples cured at 25 °C. The residual compounds after the scCO2 process, i.e. monocalcium aluminate, calcium carbonate and aluminium hydroxide are durable in normal ambient conditions. Complete carbonation of CAC is particularly important for the reinforcement of CAC with polymer fibres to improve its mechanical strength. Tue, 14 May 2013 07:52:00 GMT http://hdl.handle.net/2117/19189 2013-05-14T07:52:00Z Fernández Carrasco, Lucía; Miravitlles, C; Rius, J. no The microstructural changes occurring during supercritical carbonation (scCO2) of calcium aluminate cement (CAC) and changes to its strength have been investigated. Cylindrical specimens of CAC cured at different temperatures were prepared and then subjected to scCO2. It is shown that CAC carbonation in supercritical conditions is accelerated with a positive effect on the compressive strength. Due to the scCO2 treatment, both conversion and alkaline hydrolysis are avoided. The best behaviour of the studied specimens was attained for samples cured at 25 °C. The residual compounds after the scCO2 process, i.e. monocalcium aluminate, calcium carbonate and aluminium hydroxide are durable in normal ambient conditions. Complete carbonation of CAC is particularly important for the reinforcement of CAC with polymer fibres to improve its mechanical strength. http://hdl.handle.net/2117/19188 Title: A Discussion of the Paper "Hydration Reactions of Nonstoichiometric Barium Orthoaluminates" by T.R.N. Kutty and M. Nayak Authors: Fernández Carrasco, Lucía Tue, 14 May 2013 07:43:11 GMT http://hdl.handle.net/2117/19188 2013-05-14T07:43:11Z Fernández Carrasco, Lucía no http://hdl.handle.net/2117/19187 Title: Synthesis and Crystal Structure Solution of Potassium Dawsonite: an intermediate compound in the alkaline hydrolysis of Calcium Aluminate Cements Authors: Fernández Carrasco, Lucía; Puertas, F; Blanco-Varela, M T; Vázquez, T; Rius, J. Abstract: Potassium dawsonite is formed as an intermediate compound during the alkaline hydrolysis (AH) in calcium aluminate cements (CACs). A synthesis method of potassium dawsonite has been developed. The crystal structure of potassium dawsonite KAl(CO3)(OH)2 has been solved by direct methods from X-ray powder diffraction data and refined with the Rietveld method. It crystallises in the orthorhombic Cmcm space group with unit cells parameters a=6.3021(3) Å, b=11.9626(5) Å, c=5.6456(3) Å and Z=4. The structure consists of carboaluminate chains, formed by the basic unit [Al2(OH)4(CO3)2]2− arranged along the c axis. The carbonate groups are placed in an alternate manner at both sides of the carboaluminate chains. The carboaluminate chains are also held together by the K+ cations that are located in the middle of three such chains. Finally, the chemical reactions explaining the AH process in CACs are postulated. Tue, 14 May 2013 07:31:53 GMT http://hdl.handle.net/2117/19187 2013-05-14T07:31:53Z Fernández Carrasco, Lucía; Puertas, F; Blanco-Varela, M T; Vázquez, T; Rius, J. no Potassium dawsonite is formed as an intermediate compound during the alkaline hydrolysis (AH) in calcium aluminate cements (CACs). A synthesis method of potassium dawsonite has been developed. The crystal structure of potassium dawsonite KAl(CO3)(OH)2 has been solved by direct methods from X-ray powder diffraction data and refined with the Rietveld method. It crystallises in the orthorhombic Cmcm space group with unit cells parameters a=6.3021(3) Å, b=11.9626(5) Å, c=5.6456(3) Å and Z=4. The structure consists of carboaluminate chains, formed by the basic unit [Al2(OH)4(CO3)2]2− arranged along the c axis. The carbonate groups are placed in an alternate manner at both sides of the carboaluminate chains. The carboaluminate chains are also held together by the K+ cations that are located in the middle of three such chains. Finally, the chemical reactions explaining the AH process in CACs are postulated. http://hdl.handle.net/2117/19147 Title: Scaling laws and the modern city Authors: Isalgue Buxeda, Antonio; Coch Roura, Helena; Serra Florensa, Rafael Abstract: A detrended fluctuation analysis (DFA) is applied to the statistics of Korean treasury bond (KTB) futures from which the logarithmic increments, volatilities, and traded volumes are estimated over a specific time lag. In this study, the logarithmic increment of futures prices has no long-memory property, while the volatility and the traded volume exhibit the existence of the long-memory property. To analyze and calculate whether the volatility clustering is due to a inherent higher-order correlation not detected by with the direct application of the DFA to logarithmic increments of KTB futures, it is of importance to shuffle the original tick data of future prices and to generate a geometric Brownian random walk with the same mean and standard deviation. It was found from a comparison of the three tick data that the higher-order correlation inherent in logarithmic increments leads to volatility clustering. Particularly, the result of the DFA on volatilities and traded volumes can be supported by the hypothesis of price changes. Thu, 09 May 2013 10:56:38 GMT http://hdl.handle.net/2117/19147 2013-05-09T10:56:38Z Isalgue Buxeda, Antonio; Coch Roura, Helena; Serra Florensa, Rafael no A detrended fluctuation analysis (DFA) is applied to the statistics of Korean treasury bond (KTB) futures from which the logarithmic increments, volatilities, and traded volumes are estimated over a specific time lag. In this study, the logarithmic increment of futures prices has no long-memory property, while the volatility and the traded volume exhibit the existence of the long-memory property. To analyze and calculate whether the volatility clustering is due to a inherent higher-order correlation not detected by with the direct application of the DFA to logarithmic increments of KTB futures, it is of importance to shuffle the original tick data of future prices and to generate a geometric Brownian random walk with the same mean and standard deviation. It was found from a comparison of the three tick data that the higher-order correlation inherent in logarithmic increments leads to volatility clustering. Particularly, the result of the DFA on volatilities and traded volumes can be supported by the hypothesis of price changes. http://hdl.handle.net/2117/19134 Title: El detall estratègic Authors: Tudó Galí, Roger; Ricart Ulldemolins, Josep; Aguiló Aran, Claudi; Claret Martí, Jordi Wed, 08 May 2013 11:43:44 GMT http://hdl.handle.net/2117/19134 2013-05-08T11:43:44Z Tudó Galí, Roger; Ricart Ulldemolins, Josep; Aguiló Aran, Claudi; Claret Martí, Jordi no http://hdl.handle.net/2117/19105 Title: La localización intrametropolitana de las actividades de la información: un análisis para la Región Metropolitana de Barcelona 1991-2001 Authors: Marmolejo Duarte, Carlos Ramiro; Pérez Prieto, Claudia Beatriz Abstract: En este artículo se analiza la localización intrametropolitana de las actividades de la información y su dinámica de descentralización. Con este objetivo se propone una aproximación novedosa por cuanto pone el énfasis en la forma en cómo se producen las cosas o se prestan los servicios más que en el sector económico al cual pertenece la actividad. El ámbito de estudio es la Región Metropolitana de Barcelona, en el periodo comprendido entre los años 1991 y 2001. Los resultados sugieren que las actividades inmateriales, además de incrementar su protagonismo en la estructura económica metropolitana, poseen patrones de localización compactos, incluso están más concentradas que las actividades comerciales. Asimismo existe una clara concomitancia entre la estructura empresarial de cada sector económico y su tendencia locativa, cuanto más actividades relacionadas con la gestión de la información y el conocimiento tiene un sector, más acentúa su concentración espacial. Por otra parte, el análisis dinámico ha detectado que, del conjunto de actividades metropolitanas, las funciones relacionadas con la gestión de la información presentan el menor nivel de descentralización, con lo cual, el centro gana especialización, al recentralizar relativamente a las actividades con más alto valor añadido. De manera que la metrópoli adopta una estructura multipolar compleja, en donde el centro emerge como el epicentro de la ciudad del conocimiento, apoyado por los principales subcentros metropolitanos, que en conjunto estructuran y dan soporte a un territorio intersticial progresivamente especializado en actividades industriales de alta tecnología. Mon, 06 May 2013 13:27:02 GMT http://hdl.handle.net/2117/19105 2013-05-06T13:27:02Z Marmolejo Duarte, Carlos Ramiro; Pérez Prieto, Claudia Beatriz no En este artículo se analiza la localización intrametropolitana de las actividades de la información y su dinámica de descentralización. Con este objetivo se propone una aproximación novedosa por cuanto pone el énfasis en la forma en cómo se producen las cosas o se prestan los servicios más que en el sector económico al cual pertenece la actividad. El ámbito de estudio es la Región Metropolitana de Barcelona, en el periodo comprendido entre los años 1991 y 2001. Los resultados sugieren que las actividades inmateriales, además de incrementar su protagonismo en la estructura económica metropolitana, poseen patrones de localización compactos, incluso están más concentradas que las actividades comerciales. Asimismo existe una clara concomitancia entre la estructura empresarial de cada sector económico y su tendencia locativa, cuanto más actividades relacionadas con la gestión de la información y el conocimiento tiene un sector, más acentúa su concentración espacial. Por otra parte, el análisis dinámico ha detectado que, del conjunto de actividades metropolitanas, las funciones relacionadas con la gestión de la información presentan el menor nivel de descentralización, con lo cual, el centro gana especialización, al recentralizar relativamente a las actividades con más alto valor añadido. De manera que la metrópoli adopta una estructura multipolar compleja, en donde el centro emerge como el epicentro de la ciudad del conocimiento, apoyado por los principales subcentros metropolitanos, que en conjunto estructuran y dan soporte a un territorio intersticial progresivamente especializado en actividades industriales de alta tecnología. http://hdl.handle.net/2117/19095 Title: Hacia un modelo teórico del comportamiento espacial de las actividades de oficina Authors: Marmolejo Duarte, Carlos Ramiro; Roca Cladera, Josep Abstract: La teoría general de la localización clasifica en cuatro grupos a los factores que condicionan el emplazamiento de todo tipo de actividades urbanas: accesibilidad, jerarquía social, economías de aglomeración y externalidades ambientales. Sin embargo, para cada subconjunto de actividades (industria, comercio, distribución logística, etc.) existen factores, dentro de dichos grupos, cuya incidencia se eleva por encima de la del resto, conformando de esta manera cuerpos teóricos específicos. La investigación que aquí se reporta parte de la hipótesis de la existencia de un factor que de manera consustancial explica el comportamiento locativo de las actividades de oficina. Más en el fondo aún, se trata de hallar las razones profundas que articulan el cuerpo de una teoría específica sobre la localización de dichas actividades. Una vez hallado y aislado dicho factor fundamental se construye un modelo teórico de interacción espacial con el objeto de probar, en el campo empírico, la validez que de las hipótesis que de él se desprenden. Fri, 03 May 2013 13:17:49 GMT http://hdl.handle.net/2117/19095 2013-05-03T13:17:49Z Marmolejo Duarte, Carlos Ramiro; Roca Cladera, Josep no La teoría general de la localización clasifica en cuatro grupos a los factores que condicionan el emplazamiento de todo tipo de actividades urbanas: accesibilidad, jerarquía social, economías de aglomeración y externalidades ambientales. Sin embargo, para cada subconjunto de actividades (industria, comercio, distribución logística, etc.) existen factores, dentro de dichos grupos, cuya incidencia se eleva por encima de la del resto, conformando de esta manera cuerpos teóricos específicos. La investigación que aquí se reporta parte de la hipótesis de la existencia de un factor que de manera consustancial explica el comportamiento locativo de las actividades de oficina. Más en el fondo aún, se trata de hallar las razones profundas que articulan el cuerpo de una teoría específica sobre la localización de dichas actividades. Una vez hallado y aislado dicho factor fundamental se construye un modelo teórico de interacción espacial con el objeto de probar, en el campo empírico, la validez que de las hipótesis que de él se desprenden. http://hdl.handle.net/2117/19084 Title: Bioclimatism in vernacular architecture Authors: Coch Roura, Helena Abstract: Any analysis of the role played by energy in architecture is faced with serious limitations due to the lack of studies in the architectural bibliography, especially studies of popular architecture. An awareness of these limitations will allow us to understand better why architects have paid little attention to the interaction of form and energy, and to the bioclimatic approach in contemporary architecture in general. The first limitation stems from the very essence of bioclimatic analysis; energy is immaterial, difficult to represent in images, changing in time and wrongfully left out of the architectural literature. This is why it is difficult to find a basic knowledge of the functional aesthetic possibilities of bioclimatism in the cultural experience of present-day architects. The second limitation to this knowledge, even more important than the previous one, is the low value given to the more anonymous popular architecture as opposed to representative architecture. The latter is the kind of architecture built by established power, which attempts to impress the observer and clashes with, dominates, and often destroys the natural environment. This style of architecture is crammed with theoretical aesthetic concerns, which would rather create artificial environments than be integrated in the natural milieu. To sum up, it is the architecture undertaken by well-known authors, found in important buildings, which have been commented and widely appreciated by architecture critics throughout history. Nowadays, representative architecture can be said to describe the architecture found in large office buildings, which embody the legacy of such works from the history of culture as the pyramids, classic shrines, medieval castles and large Gothic cathedrals, baroque and Renaissance palaces, etc. These modern buildings, clad in glass as a symbol of their modernity, are incongruously dark and require artificial lighting during the day, while the flimsy casing separating them from the outside makes it necessary to use air conditioning all year round, even when outside conditions are pleasant. We can well affirm that these buildings are so wrong that they work worse than the climate. In comparison with this type of representative architecture, we find popular architecture, performed by the people as a direct response to their needs and values. These buildings show a greater respect for the existing environment, whether natural or artificial. They do not reflect theoretical aesthetic pretensions and use local materials and techniques as far as possible, repeating over and over again the course of history models which take the constraints imposed by the climate fully into account. Our popular architecture—so often forgotten in official circles—may well be the kind which can best teach us today how to assimilate the bioclimatic approach in the practice of architectural design. However, we should not consider these solutions to be models to copy in current architecture. Our technical capacity and our cultural grounding prevent us from returning to these obsolete architecture forms, but what may be of use as a lesson and a source of inspiration is the attitude of the builders of this popular architecture, which recovers a relationship to the environment which has been lost in the more official architecture of the 20th century. Thu, 02 May 2013 13:52:36 GMT http://hdl.handle.net/2117/19084 2013-05-02T13:52:36Z Coch Roura, Helena no Any analysis of the role played by energy in architecture is faced with serious limitations due to the lack of studies in the architectural bibliography, especially studies of popular architecture. An awareness of these limitations will allow us to understand better why architects have paid little attention to the interaction of form and energy, and to the bioclimatic approach in contemporary architecture in general. The first limitation stems from the very essence of bioclimatic analysis; energy is immaterial, difficult to represent in images, changing in time and wrongfully left out of the architectural literature. This is why it is difficult to find a basic knowledge of the functional aesthetic possibilities of bioclimatism in the cultural experience of present-day architects. The second limitation to this knowledge, even more important than the previous one, is the low value given to the more anonymous popular architecture as opposed to representative architecture. The latter is the kind of architecture built by established power, which attempts to impress the observer and clashes with, dominates, and often destroys the natural environment. This style of architecture is crammed with theoretical aesthetic concerns, which would rather create artificial environments than be integrated in the natural milieu. To sum up, it is the architecture undertaken by well-known authors, found in important buildings, which have been commented and widely appreciated by architecture critics throughout history. Nowadays, representative architecture can be said to describe the architecture found in large office buildings, which embody the legacy of such works from the history of culture as the pyramids, classic shrines, medieval castles and large Gothic cathedrals, baroque and Renaissance palaces, etc. These modern buildings, clad in glass as a symbol of their modernity, are incongruously dark and require artificial lighting during the day, while the flimsy casing separating them from the outside makes it necessary to use air conditioning all year round, even when outside conditions are pleasant. We can well affirm that these buildings are so wrong that they work worse than the climate. In comparison with this type of representative architecture, we find popular architecture, performed by the people as a direct response to their needs and values. These buildings show a greater respect for the existing environment, whether natural or artificial. They do not reflect theoretical aesthetic pretensions and use local materials and techniques as far as possible, repeating over and over again the course of history models which take the constraints imposed by the climate fully into account. Our popular architecture—so often forgotten in official circles—may well be the kind which can best teach us today how to assimilate the bioclimatic approach in the practice of architectural design. However, we should not consider these solutions to be models to copy in current architecture. Our technical capacity and our cultural grounding prevent us from returning to these obsolete architecture forms, but what may be of use as a lesson and a source of inspiration is the attitude of the builders of this popular architecture, which recovers a relationship to the environment which has been lost in the more official architecture of the 20th century. http://hdl.handle.net/2117/19051 Title: Cobertes complexes Authors: Avellaneda Diaz-Grande, Jaime; Zamora i Mestre, Joan-Lluís; Aguiló Aran, Claudi Tue, 30 Apr 2013 10:47:55 GMT http://hdl.handle.net/2117/19051 2013-04-30T10:47:55Z Avellaneda Diaz-Grande, Jaime; Zamora i Mestre, Joan-Lluís; Aguiló Aran, Claudi no http://hdl.handle.net/2117/19050 Title: La competitivitat de la construcció: el cas dels habitatges Authors: Avellaneda Diaz-Grande, Jaime; González Barroso, José M.; Aguiló Aran, Claudi Tue, 30 Apr 2013 10:44:06 GMT http://hdl.handle.net/2117/19050 2013-04-30T10:44:06Z Avellaneda Diaz-Grande, Jaime; González Barroso, José M.; Aguiló Aran, Claudi no http://hdl.handle.net/2117/19048 Title: Tolerancies i coordinacio dimensional Authors: Avellaneda Diaz-Grande, Jaime; Aguiló Aran, Claudi Tue, 30 Apr 2013 10:40:51 GMT http://hdl.handle.net/2117/19048 2013-04-30T10:40:51Z Avellaneda Diaz-Grande, Jaime; Aguiló Aran, Claudi no