Disseny d'una màquina carregadora de planxa a l'empresa Serralleria i Alumini Vilaró (S.A.V)

Les empreses sempre han buscat com optimitzar el màxim els seus recursos i ser més eficients a la hora de realitzar les tasques que li han estat encomanades. És per aquest motiu que constantment les empreses realitzen estudis i valoracions de com poder millorar dia a dia. Aquest fet no és diferenciador a l’empresa Serralleria i Alumini Vilaró (S.A.V), que dia a dia estudia com optimitzar els seus processos o de vegades introduir-ne de nous per tal d’expandir la seva oferta de serveis. L’empresa és dedica a la fabricació de peces metàl•liques el procés ja sigui només de tall i mecanitzat, plegat, soldadura, acabats en inoxidable, pintura i fins i tot embalatge pel que fa a la part productiva, respecte a la part d’oficina tècnica també ofereix serveis de desenvolupament de productes segons especificacions del client i reenginyeria de qualsevol producte, analitzant la part que és vol millorar. En l’actualitat l’empresa ha detectat una mancança que creu que es podria solucionar, el problema és que l’empresa disposa de varies màquines de tall, entre les quals hi ha una màquina de tall làser i el problema principal és que la càrrega de les planxes del calaix de magatzem a la bancada de la màquina es realitza o bé manualment o a través d’un gripper sostingut al pont grua, depenent del pes de la planxa a transportar. L’objectiu principal d’aquest treball és fer el disseny d’una màquina que permeti automatitzar el procés de transportar la planxa metàl•lica del calaix de magatzem dipositat sobre una taula mòbil a la bancada de la màquina de tall. El disseny que pretenem fer és complet començant per fer un disseny estructural de la màquina més els seus respectius càlculs, moviments que volem aconseguir, tria de components ( motors, sensors ...), elaboració d’un pressupost per poder fer una estimació i finalment la elaboració del programa de control de tota la màquina més la interacció amb la màquina a través d’una pantalla tàctil. Es a dir, el que pretenem és realitzar un projecte que puguem fabricar en la realitat utilitzant tota la informació continguda dins del mateix

Disseny d'una màquina carregadora de planxa a l'empresa Serralleria i Alumini Vilaró (S.A.V)

Les empreses sempre han buscat com optimitzar el màxim els seus recursos i ser més eficients a la hora de realitzar les tasques que li han estat encomanades. És per aquest motiu que constantment les empreses realitzen estudis i valoracions de com poder millorar dia a dia. Aquest fet no és diferenciador a l’empresa Serralleria i Alumini Vilaró (S.A.V), que dia a dia estudia com optimitzar els seus processos o de vegades introduir-ne de nous per tal d’expandir la seva oferta de serveis. L’empresa és dedica a la fabricació de peces metàl•liques el procés ja sigui només de tall i mecanitzat, plegat, soldadura, acabats en inoxidable, pintura i fins i tot embalatge pel que fa a la part productiva, respecte a la part d’oficina tècnica també ofereix serveis de desenvolupament de productes segons especificacions del client i reenginyeria de qualsevol producte, analitzant la part que és vol millorar. En l’actualitat l’empresa ha detectat una mancança que creu que es podria solucionar, el problema és que l’empresa disposa de varies màquines de tall, entre les quals hi ha una màquina de tall làser i el problema principal és que la càrrega de les planxes del calaix de magatzem a la bancada de la màquina es realitza o bé manualment o a través d’un gripper sostingut al pont grua, depenent del pes de la planxa a transportar. L’objectiu principal d’aquest treball és fer el disseny d’una màquina que permeti automatitzar el procés de transportar la planxa metàl•lica del calaix de magatzem dipositat sobre una taula mòbil a la bancada de la màquina de tall. El disseny que pretenem fer és complet començant per fer un disseny estructural de la màquina més els seus respectius càlculs, moviments que volem aconseguir, tria de components ( motors, sensors ...), elaboració d’un pressupost per poder fer una estimació i finalment la elaboració del programa de control de tota la màquina més la interacció amb la màquina a través d’una pantalla tàctil. Es a dir, el que pretenem és realitzar un projecte que puguem fabricar en la realitat utilitzant tota la informació continguda dins del mateix

A note on the application of integrals involving cyclic products kernels

A l'estadística de processos estocàstics i camps aleatoris, una funció de moments o un cumulant d'un estimador de la funció de correlació o de la densitat espectral sovint pot contenir una integral amb un producte cíclic de nuclis. En aquest treball es defineix i s'investiga aquesta classe d'integrals i es demostra la desigualtat de Young-Hölder que permet estudiar el comportament asimptòtic de les esmentades integrals en la situació quan els nuclis depenen d'un pàràmetre. Es considera una aplicació al problema d'estimació de la funció de resposta en un sistema de Volterra.

Distortion of wreath products in some finitely presented groups

"Vegeu el resum a l'inici del document del fitxer adjunt."

Between specialization and globalization. The marketing of agrarian products and its environmental impacts seen from a historical perspective: the province of Barcelona in the mid-nineteenth century

Ecological economics has five good reasons to consider that economic globalisation, spurred by commercial and financial fluxes, to be one of the main driving forces responsible for causing environmental degradation to our planet. The first, is the energy consumption and the socio-environmental impacts which long-distance haulage entails. The second, is the ever-increasing flow of goods to far-away destinations which renders their recycling practically impossible. This is particularly significant, because it prevents the metabolic lock of the nutrients present in food and other agrarian products from taking place. The third, is that the high degree of specialization attained in agriculture, forestry, cattle, mining and industry in each region, generates deleterious effects not only on the eco-landscape structure of the uses of the soil, but on the capability to provide habitat and environmental functions to maintain biodiversity as well

Effect of high pressure processing on the microbiology of skin-vacuum packaged sliced meat products: cooked pork ham, dry cured pork ham and marinated beef loin

High hydrostatic pressure is being increasingly investigated in food processing. It causes microbial inactivation and therefore extends the shelf life and enhances the safety of food products. Yeasts, molds, and vegetative cells of bacteria can be inactivated by pressures in the range of 200 to 700 MPa. Microorganisms are more or less sensitive to pressure depending on several factors such as type, strain and the phase or state of the cells. In general, Gram-positive organisms are usually more resistant than Gram-negative. High pressure processing modifies the permeability of the cell membrane, the ion exchange and causes changes in morphology and biochemical reactions, protein denaturations and inhibition of genetic mechanisms. High pressure has been used successfully to extend the shelf life of high-acid foods such as refrigerated fruit juices, jellies and jams. There is now an increasing interest in the use of this technology to extend the shelf life of low-acid foods such as different types of meat products.

Bioequivalence of meat products treated with high pressure processing

The effects of high pressure on the composition of food products have not been evaluated extensively. Since, it is necessary to take in consideration the possible effects in basis to the changes induced in the bio molecules by the application of high pressures. The main effect on protein is the denaturation, because the covalent bonds are not affected; however hydrogen bonding, hydrophobic and intermolecular interactions are modified or destroyed. 1 High pressure can modify the activity of some enzymes. If this is done the proteolysis and lipolysis could be more or less intense and the content of free amino acids and fatty acids will be different. This could be related to the bioavailability of these compounds. Low pressures (100 MPa) have been shown to activate some enzymes (monomeric enzymes). Higher pressures induce loss of the enzyme activity. However some enzymes are very stable (ex. Lipase ~ 600 - 1000 MPa). Lipoxygenase is less stable, and there is little information about the effects on antioxidant enzymes. Other important issue is the influence of high pressure on oxidation susceptibility. This could modify the composition of lipids if the degree of the oxidation would have been higher or lower than in the traditional product. Pressure produces the damage of cell membranes favouring the contact between substrates and enzymes, exposure to oxidation of membrane fatty acids and loos of the efficiency of vitamin E. These effects can also affect to protein oxidation. In this study different compounds were analysed to establish the differences between non-treated and high-pressure treated products.

On the intersection of free subgroups in free products of groups

"Vegeu el resum a l'inici del document del fitxer adjunt."

Study of the influence of grain size and precipitates on the electromagnetic losses in different grades of non-oriented fully processed electrical steel

The study was performed in the installations of OCAS, a Steel Research Centre of ArcelorMittal. Taking M32 steel (3.25%Si+0.9%Al) as the basis chemical composition and three different thicknesses (0.35, 0.5 and 0.65mm), different annealing conditions (temperature and time) have been applied in the laboratory simulator at St. Chély, France. The aim was to link annealing parameters, grain size and energy loss. It was determined the optimum annealing parameters to reach the lowest power losses for three different grades of non-oriented fully processed electrical steel. In addition, M250-50 samples having different magnetic behaviour (high and low losses) but the same grain size and texture, have been analyzed in terms of TEM observations of their precipitates, in the University of Marseille. The results reveal that a high amount of medium and big precipitates (&10 nm) worsen the magnetic properties of the material. The small precipitates (&10nm) do not have a strong influence on the magnetic properties. The presence of precipitates can have a great influence on the power losses and further work is clearly necessary.

Link between microstructure and properties in new metallurgical concepts for very low loss non-oriented electrical steel

The influence of chemistry and soaking temperature (maximal temperature of the continuous annealing) on the final properties of non-oriented electrical steels has been studied. With this objective two different studies have been performed. First the Mn, Ni and Cr content of a low loss electrical steel composition has been modified. An intermediate content and a high content of each element has been added in order to study the influence of this components on the magnetic looses, grain size and texture. Secondly the influence of the soaking temperature on magnetic properties, grain size and oxidation in four grades of non-oriented electrical steels (Steel A, B, C and D) was studied.

On finite unions and finite products with the D-property

We show that the product of a subparacompact C-scattered space and a Lindelöf D-space is D. In addition, we show that every regular locally D-space which is the union of a finite collection of subparacompact spaces and metacompact spaces has the D-property. Also, we extend this result from the class of locally D-spaces to the wider class of D-scattered spaces. All the results are shown in a direct way.

Tensor products of Leavitt path algebras

Vegeu el resum a l'inici del document del fitxer adjunt.

Environmental Tax on Products and Services Based on Their Carbon Footprint: A Case Study of the Pulp and Paper Sector

The main aim of this work is to define an environmental tax on products and services based on their carbon footprint. We examine the relevance of conventional life cycle analysis (LCA) and environmentally extended input-output analysis (EIO) as methodological tools to identify emission intensities of products and services on which the tax is based. The short-term price effects of the tax and the policy implications of considering non-GHG are also analyzed. The results from the specific case study on pulp production show that the environmental tax rate based on the LCA approach (1,8%) is higher than both EIO approaches (0,8% for product and 1,4% for industry approach), but they are comparable. Even though LCA is more product specific and provides detailed analysis, EIO would be the more relevant approach to apply economy wide environmental tax. When the environmental tax considers non-GHG emissions instead of only CO2, sectors such as agriculture, mining of coal and extraction of peat, and food exhibit higher environmental tax and price effects. Therefore, it is worthwhile for policy makers to pay attention on the implication of considering only CO2 tax or GHG emissions tax in order for such a policy measure to be effective and meaningful. Keywords: Environmental tax; Life cycle analysis; Environmental input-output analysis.

On spectral approximation, Folner sequences and crossed products

In this article we review first some of the possibilities in which the notions of Fo lner sequences and quasidiagonality have been applied to spectral approximation problems. We construct then a canonical Fo lner sequence for the crossed product of a concrete C* -algebra and a discrete amenable group. We apply our results to the rotation algebra (which contains interesting operators like almost Mathieu operators or periodic magnetic Schrödinger operators on graphs) and the C* -algebra generated by bounded Jacobi operators.