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UPCommons, el portal d'accés obert al coneixement de la UPC, està format pel conjunt de dipòsits institucionals oberts de la UPC i té com a missió garantir la preservació de la producció docent i de recerca cientificotècnica de la Universitat, maximitzant-ne la visibilitat i, conseqüentment, incrementant-ne l’impacte en la docència i la recerca de tot el món.
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Centro residencial de personas mayores y ludoteca : el Carmel, Barcelona

dc., 02/14/2018 - 11:34
Centro residencial de personas mayores y ludoteca : el Carmel, Barcelona Huguet Pagés, Alejandro El proyecto consiste en la realización de un centro residencial de personas mayores y una ludoteca para niños en el barrio de El Carmel, Barcelona. El análisis demográfico del barrio hace que el uso de este equipamiento sea necesario, al tratarse de un barrio con la edad media más avanzada que la del resto de la ciudad. Además, al ser un edificio público se ha optado por hacer la planta baja de la residencia abierta al barrio. La topografía de las calles colindantes al solar ha sido el principal inconveniente al realizar la propuesta, ya que hay un desnivel de casi 10 metros entre la cota inferior y la superior. De este principal inconveniente han nacido las ideas principales de proyecto, determinando los accesos, circulaciones, patios, iluminación, visuales, etc.
Categories: Novetats

Capgirem "La Canigó" : reforma del local dels Castellers de Sant Cugat

dc., 02/14/2018 - 11:25
Capgirem "La Canigó" : reforma del local dels Castellers de Sant Cugat Jiménez Llàdser, Laia El projecte sorgeix d’un treball exhaustiu realitzat durant dos quadrimestres al tap PUD, liderat per en Coque Claret i en Dani Calatayud. L’encàrrec era buscar una nova seu per als castellers de Sant Cugat, tant de nova construcció com existent. Després d’un triatge i d’una votació popular, en el segon quadrimestre es van desenvolupar, amb més detall, dues possibles propostes. En el Projecte Final de Grau es desenvolupa amb detall una d’aquestes propostes sorgides del taller. La intervenció consisteix en adequar i rehabilitar la sala polivalent, anomenada Canigó, on actualment assagen els castellers, per encabir-hi la seu social. S’ha de tenir en compte, però, que aquest espai el comparteixen amb un equip de gimnàstica rítmica, que requereix unes condicions tant de superfície com d’alçada. Amb aquestes premisses, s’acota la intervenció interior i fa que només es pugui intervenir en una crugia de la sala. Així doncs, les actuacions impliquen una reforma de l’espai interior, i una reestructuració urbana de l’espai exterior proper, afectant i ampliant la secció d’escalada del Club Muntanyenc Sant Cugat. El sistema constructiu es basa en dues bigues Vieerendel, ancorades a l’estructura existent de la sala. Això comporta un reforç tant de la fonamentació com dels pilars existents per poder suportar les noves càrregues. Els tancaments interiors es faran amb un sistema lleuger i reversible, tenint en compte que l’àmbit d’actuació serà cedit temporalment. És un projecte que s’està treballant conjuntament amb l’Ajuntament de Sant Cugat, promotor de fer aquest espai local oficial dels castellers.
Categories: Novetats

Feasibility of detecting natural frequencies of hydraulic turbines while in operation, using strain gauges

dc., 02/14/2018 - 10:54
Feasibility of detecting natural frequencies of hydraulic turbines while in operation, using strain gauges Valentín Ruiz, David; Presas Batlló, Alexandre; Bossio, Matias; Egusquiza Montagut, Mònica; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen Nowadays, hydropower plays an essential role in the energy market. Due to their fast response and regulation capacity, hydraulic turbines operate at off-design conditions with a high number of starts and stops. In this situation, dynamic loads and stresses over the structure are high, registering some failures over time, especially in the runner. Therefore, it is important to know the dynamic response of the runner while in operation, i.e., the natural frequencies, damping and mode shapes, in order to avoid resonance and fatigue problems. Detecting the natural frequencies of hydraulic turbine runners while in operation is challenging, because they are inaccessible structures strongly affected by their confinement in water. Strain gauges are used to measure the stresses of hydraulic turbine runners in operation during commissioning. However, in this paper, the feasibility of using them to detect the natural frequencies of hydraulic turbines runners while in operation is studied. For this purpose, a large Francis turbine runner (444 MW) was instrumented with several strain gauges at different positions. First, a complete experimental strain modal testing (SMT) of the runner in air was performed using the strain gauges and accelerometers. Then, the natural frequencies of the runner were estimated during operation by means of analyzing accurately transient events or rough operating conditions.
Categories: Novetats

Power swing generated in Francis turbines by part load and overload instabilities

dc., 02/14/2018 - 10:45
Power swing generated in Francis turbines by part load and overload instabilities Valentín Ruiz, David; Presas Batlló, Alexandre; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Bossio, Matias Hydropower plays a key role in the actual energy market due to its fast response and regulation capacity. In that way, hydraulic turbines are increasingly demanded to work at off-design conditions, where complex flow patterns and cavitation appear, especially in Francis turbines. The draft tube cavitation surge is a hydraulic phenomenon that appears in Francis turbines below and above its Best Efficiency Point (BEP). It is a low frequency phenomenon consisting of a vortex rope in the runner outlet and draft tube, which can become unstable when its frequency coincides with a natural frequency of the hydraulic circuit. At this situation, the output power can significantly swing, endangering the electrical grid stability. This study is focused on the detection of these instabilities in Francis turbines and their relationship with the output power swings. To do so, extensive experimental tests for different operating conditions have been carried out in a large prototype Francis turbine (444 MW of rated power) within the frame of the European Project Hyperbole (FP7-ENERGY-2013-1). Several sensors have been installed in the hydraulic circuit (pressure sensors in the draft tube, spiral casing, and penstock), in the rotating and static structures (vibration sensors, proximity probes, and strain gauges in the runner and in the shaft), as well as in the electrical side (output power, intensity, and voltage). Moreover, a numerical Finite Element Method (FEM) has been also used to relate the hydraulic excitation with the output power swing.
Categories: Novetats

Open source software ecosystems : a systematic mapping

dc., 02/14/2018 - 10:08
Open source software ecosystems : a systematic mapping Franco Bedoya, Óscar Hernán; Ameller, David; Costal Costa, Dolors; Franch Gutiérrez, Javier Context: Open source software (OSS) and software ecosystems (SECOs) are two consolidated research areas in software engineering. OSS influences the way organizations develop, acquire, use and commercialize software. SECOs have emerged as a paradigm to understand dynamics and heterogeneity in collaborative software development. For this reason, SECOs appear as a valid instrument to analyze OSS systems. However, there are few studies that blend both topics together. Objective: The purpose of this study is to evaluate the current state of the art in OSS ecosystems (OSSECOs) research, specifically: (a) what the most relevant definitions related to OSSECOs are; (b) what the particularities of this type of SECO are; and (c) how the knowledge about OSSECO is represented. Method: We conducted a systematic mapping following recommended practices. We applied automatic and manual searches on different sources and used a rigorous method to elicit the keywords from the research questions and selection criteria to retrieve the final papers. As a result, 82 papers were selected and evaluated. Threats to validity were identified and mitigated whenever possible. Results: The analysis allowed us to answer the research questions. Most notably, we did the following: (a) identified 64 terms related to the OSSECO and arranged them into a taxonomy; (b) built a genealogical tree to understand the genesis of the OSSECO term from related definitions; (c) analyzed the available definitions of SECO in the context of OSS; and (d) classified the existing modelling and analysis techniques of OSSECOs. Conclusion: As a summary of the systematic mapping, we conclude that existing research on several topics related to OSSECOs is still scarce (e.g., modelling and analysis techniques, quality models, standard definitions, etc.). This situation calls for further investigation efforts on how organizations and OSS communities actually understand OSSECOs.
Categories: Novetats

CFD study of the flow of a non-Newtonian fluid through a flow splitting geometry

dt., 02/13/2018 - 20:53
CFD study of the flow of a non-Newtonian fluid through a flow splitting geometry Pera Caymari, Arnau
Categories: Novetats

Development of reduced order models for wind farm control

dt., 02/13/2018 - 20:45
Development of reduced order models for wind farm control Fortes Plaza, Alberto Background: Wind energy is one of the leading renewable energies that take part in the current transition from the usage of traditional fossil-fuel energies to green ones. The potential and development of wind power is increasing constantly. Therefore, continuous studies are being carried out in order to improve the power extraction of wind farms. Study: This Master’s Thesis aims to obtain multiple-Input-multiple-Output Reduced-Order Models (IOROMs) that are able to capture the main dynamics present in wind turbine wake flows within wind farms during transients and during operation. This dynamics can be excited via different inputs, such as wind turbine’s yaw angle, generator torque, pitch angle, among others. In this work, the study will be conducted by analyzing the response of the system to yaw angle variations, although the same procedure explained is valid for other inputs. The models developed are also mainly intended for capturing the relation between output magnitudes, such as wind turbine power output, bending moments, lateral forces, etc., and the given inputs to the system. Beside, order reduction is key to this work, since the models are expected to reproduce with acceptable fidelity high computationally costly simulations. The study has been conducted based on CFD (Computational Fluid Dynamics) simulation data that are considered as the starting point of the work. Results & Conclusions: The models developed in this work present considerable agreement with respect to the results obtained via CFD simulations. Owing to the symmetry that the yawing motion presents for the system, the operational range has been divided into two sides, namely the positive yaw angles side and the negative yaw angles side. The results for both cases are successful in terms of flow and power output reconstruction. Therefore, the models can predict within seconds the behavior of wind farms whose performance takes days to be known through CFD simulations. This work also presents several improvements as future upgrade for reduced-order models obtained from CFD data. Some of these improvements deal with operational ranges, sample time, and data collection, inter alia.
Categories: Novetats

Assessment of tannery solid waste management : a case of Sheba Leather Industry in Wukro (Ethiopia)

dt., 02/13/2018 - 20:40
Assessment of tannery solid waste management : a case of Sheba Leather Industry in Wukro (Ethiopia) Piera Framis, Cristina This cooperation project was born with the motivation of helping and proposing solutions for a real environmental problem in a developing country that do not have easy access to facilities and services. The main objective of the project is based on analysing the solid wastes generated by a tannery named Sheba Leather Industry from Wukro, Ethiopia, in order to suggest appropriate solid waste management practices. The project studies the possibility of implementing the composting method as a solution to treat part of the waste. Ethiopia is well known for its largest livestock population. The production of leather from skins and hides is one of the leading industrial sectors in the country. The tanning industry is one of the most polluting industries generating large quantities of solid wastes and creating negative environmental impacts. Aiming to approach this problem, in this study, assessment on solid waste management practices and characterization of the solid wastes generated by Sheba Leather Industry were carried out so that suitable tannery solid waste management solutions could be proposed. The different operations performed during the leather manufacturing were examined and it was found that the company generates a total of 5,190 tonnes of solid waste every year. These wastes were physicochemically characterized. At that moment, the overall solid wastes generated are disposed to an open dumping area on the surrounding of the industry without receiving any previous treatment and, therefore, the surrounding area is being polluted. Consequently, it was suggested the possibility of composting the non-containing chrome wastes such as hair, fleshings and trimmings with other organic matter in order to obtain a soil fertilizer that could be used to improve the quality of the damaged soils. One sampling was conducted showing that the decomposition of the raw materials occurred conveniently. However, the hair waste showed difficulties to decompose, and the company carried out a second sampling excluding that waste. In order to perform this study, it was necessary to travel to Wukro, Ethiopia, and work on site. The research entailed 5,584.55 €. The possibility of composting with the sludge, a hazardous solid waste containing chrome from the wastewater treatment, has been also theoretically studied. It is feasible to use this technology in order to reduce significantly the volume of the waste and improve its quality before disposing it in a secure landfill. In addition, a composting plant capable of treating the free of chrome tannery wastes generated was designed and described. It occupies a total area of 2,500 m2 and includes a reception/mixing unit, a piles unit, a deposit for leachate collection, and a site office. The idea is based on a unique pile of great dimensions (90.21 m of length x 18 m of width x 3 m of height) that needs to be periodically turned and water. The dimensions were determined considering that the plant receives 72 tonnes of waste every three days. The composting plant will give work to three operators and the economic study has shown the necessity of a financial aid of 25,500 € every year to assure its continuity. This proposal has been considered as an environmental friendly solution to deal with part of the waste and obtain a benefit from it. Further research is recommended in order to propose more solutions and avoid the adverse consequences of disposing waste without treating it previously.
Categories: Novetats

Estudi d'optimització energètica del centre de dades Mare Nostrum

dt., 02/13/2018 - 20:24
Estudi d'optimització energètica del centre de dades Mare Nostrum Gonzalez Sanchez, Debora En el present document es plantegen diverses alternatives amb l’objectiu de millorar la eficiència energètica dels centres de dades. Aquests tipus d’edificis contribueixen significativament al consum global del planeta, tant per la seva elevada densitat de demanda energètica, com pel ràpid i creixent desplegament arreu del mon. Per a aquest estudi, s’adopta un cas d’estudi al voltant d’un centre de dades concret, com és l’anomenat Mare Nostrum (Barcelona, UPC). Per això, aquest document conté la informació necessària per entendre què és un centre de dades, quines són les tipologies de centre de dades existents actualment, quines aplicacions se’ls hi pot donar i quins són els aspectes que es poden optimitzar que afecten directament al consum elèctric del centre de dades. Els dos principals punts de millora són, per una banda, l’optimització del disseny del sistema elèctric i, per altra banda, l’optimització del disseny del sistema de refrigeració, al ser les dues àrees que suposen major consum. En quant al sistema elèctric, conté molts elements redundants existents per evitar que el centre de dades es pugui veure afectat en un possible tall del subministrament elèctric que fan que, ja sigui per sistemes de bateries o per un sistema de generació dièsel, el centre de dades segueixi funcionant amb una autonomia limitada suficient per suportar el tall en l’alimentació. En quant al sistema de refrigeració necessari per al correcte funcionament dels components electrònics, que han de romandre en unes condicions molt específiques de temperatura, té certes ineficiències degudes al sistema de control de les màquines frigorífiques, que tenen un consum molt elevat a causa de la gran dissipació de calor dels servidors. S’efectuarà primerament un estudi d’alternatives que plantegin una solució dintre de les àrees de major consum (el sistema elèctric i el sistema de refrigeració) i, finalment, es realitzarà un estudi específic, tant tècnic com econòmic, d’aquella alternativa aplicada al centre de dades específic Mare Nostrum. Es consideren concloents els resultats obtinguts perquè els objectius plantejat s’han assolit. S’ha aconseguit plantejar una proposta que millori l’eficiència energètica del centre de dades Mare Nostrum.
Categories: Novetats

Anàlisi del consum energètic al campus Nord

dt., 02/13/2018 - 20:13
Anàlisi del consum energètic al campus Nord Sánchez Bergés, Alejandro L’objectiu del present treball és analitzar el consum energètic al Campus Nord (CN) per a determinar perquè difereixen els consums mesurats per la UPC i els mesurats per la companyia elèctrica. Per aconseguir-ho, s’ha de conèixer i comprendre com funciona un sistema de monitorització. Seguidament, s’ha d’estudiar l’evolució del consum elèctric per a cada edifici del CN, identificant la procedència de tots els consums elèctrics. Això permetrà detectar la ubicació dels errors responsables de la diferència entre els consums mesurats per la UPC i per la companyia elèctrica. En primer lloc, s’explica resumidament el funcionament dels sistemes de monitorització de consums similars al emprat per la UPC. De forma més detallada, s’explica també el funcionament del sistema d'informació de recursos energètics i aigua (SIRENA), que és el sistema de monitorització emprat per la UPC. A més a més, s’estudia l’Informe SIRENA del any pertinent, que en aquest cas és 2016. Seguidament, s’estudia la distribució general del Campus Nord i s’identifiquen els edificis subjectes als anàlisis d’aquest treball. A continuació, s’ha realitzat un anàlisi dels consums elèctrics a l’any 2016, tant a nivell del campus en general com per a cada edifici en concret. També, s’ha estudiat l’evolució de dits consums mitjançant l’elaboració de gràfics, que han permès interpretar les dades de manera molt més intuïtiva. Finalment, analitzant els resultats d’aquest estudi, s’han detectat errors en la comptabilització dels consums elèctrics de certs edificis, identificant així la causa per la qual els consums mesurats per la UPC i els mesurats per la companyia elèctrica difereixen. Conseqüentment, es van realitzar estimacions d’aquells consums mal comptabilitzats per a obtenir una xifra de consum total més propera a la real. Les dades s’han obtingut del sistema d’informació SIRENA i del Servei d’Infraestructures de la UPC (SI). La manca de disponibilitat d’algunes dades, ha limitat l’anàlisi i l’obtenció de resultats més concloents. Malgrat això, el treball ha identificat aquells aspectes que provocaven errors i altres aspectes que cal millorar. D’aquesta manera, es podrà incidir correctament en els factors que comportaran un major estalvi energètic.
Categories: Novetats

Solar potential assessment: comparison using LiDAR data and PVsyst

dt., 02/13/2018 - 20:03
Solar potential assessment: comparison using LiDAR data and PVsyst Pérez Amigó, Laura Energy consumption is on a permanent rise and it is becoming increasingly concentrated in cities. Hence, cities have to work on saving energy and being more efficient by finding sources with great potential to produce their own energy and implanting the correct policies. Photovoltaics is the renewable energy technology with the higher potential in the urban context and Sweden is highly committed on its investment since it is the less developed renewable source in the country. The aim of the thesis is to compare two methodologies and determine which one is better or gives more relevant information for this kind of studies in order to evaluate how good a solar map is. For doing this, the first step is to create a solar map to have a general idea about the solar potential and to know which roofs are more suitable to install PV systems. This is made with LiDAR data using ArcGIS and SEES software. After that, another study on the quantity of solar power that could be obtained from those roofs will be performed using PVsyst, where it is possible to develop an entire PV system installation and obtain more exhaust results on energy production and shadowing. Four buildings are going to be evaluated, two public ones located in Gävle city centre (Library and Concert House) and two residential ones located in Sätra. Factors such as the optimal tilt, the best azimuth angle and the distance between panel rows are dimensioned in order to reduce shading loss and improve the performance ratio of the system in PVsyst. The final system is defined with 10° tilt, south orientation (0° azimuth), 1.5meters distance between rows and modules in strings of 9 panels connected in series for the four buildings. The simulated production from the best alternative is compared with the solar map results. Since the solar map contains information about total yearly irradiation, the energy production is obtained by means of visual exploration of the results combined with simple calculations that include GCR and system efficiency. The results show that a solar map is a reliable tool to obtain a general estimation of the solar potential in buildings but it is necessary to first identify its limitations and be able to filter the results. On the other hand, PVsyst software allows making several simulations and eases to obtain a PV system in a building or structure with detailed results of the system components. It can be concluded that since the PVsyst only allows to work with specific buildings or structures, a solar map permits big amounts of data calculations. It can be said that a solar map takes part in the process of obtaining a pre-project and the PVsyst is used in the project when a real installation is sized. Nevertheless, both methods are found to be reliable and suitable for solar potential assessment works since the results obtained match.
Categories: Novetats

Disseny d'un sistema domòtic per a un habitatge unifamiliar

dt., 02/13/2018 - 19:01
Disseny d'un sistema domòtic per a un habitatge unifamiliar Borrell I Roig, Marc Aquest projecte es basa a dissenyar, construir i validar un sistema domòtic que permeti als membres d'una casa familiar automatitzar i monitorar processos domèstics o condicions ambientals per millorar la qualitat de vida. Per tal de tenir una experiència completa, es desenvolupa tant hardware com software. Per a fer-ho, s'utilitza l'entorn de programació de Node-RED, la llibreria Bootstrap 4, el protocol de comunicació MQTT, la base de dades InfluxDB, la llibreria de JavaScript Chart.js, el sistema operatiu específic Mongoose OS, el microcontrolador ESP8266 i finalment la plataforma en línia Dialogflow. Amb totes aquestes eines i mètodes, es dissenya el programa principal i els perifèrics. El resultat d'aquest treball és la implementació real del sistema domòtic descrit anteriorment, en una habitació. Principalment es disposa d'un servidor, sensors, interruptors i diversos relés, tots testejats i validats fins a la final implementació. La conclusió principal d'aquest projecte és l'assoliment dels objectius marcats a l'inici del període de treball, tant en l'àmbit teòric com en el pràctic. Es disposa d'una habitació completament domotitzada, amb control sobre aparells elèctrics i monitoratge de sensors utilitzant múltiples interfícies d'usuari.
Categories: Novetats

Simulació i control d'una xarxa HVDC per a la integració de parcs eòlics marins

dt., 02/13/2018 - 18:59
Simulació i control d'una xarxa HVDC per a la integració de parcs eòlics marins Salmoral Parramon, Gerard El projecte presenta l’estudi d’un parc eòlic marí des d’un punt de vista elèctric. S’estudia l’anàlisi dinàmica del control droop emprat en les xarxes d'alta tensió en corrent continu HVDC (High Voltage Direct Current) que interconnecten els parcs eòlics marins amb la xarxa elèctrica terrestre principal. Per dur a terme l’estudi, s’han seleccionat els diferents elements que composen aquest tipus de sistema, incloent el seu enllaç amb la banda de xarxa elèctrica i amb la banda de l’aerogenerador. Mitjançant el programari Matlab Simulink® i amb l’ajut de la llibreria Simscape, s’han pogut dur a terme les simulacions necessàries per poder comprovar el correcte funcionament del sistema. Val a dir que s’estudien una configuració punt a punt, una configuració de tres terminals i, finalment, una de quatre terminals HVDC. L’objectiu és valorar l'efecte de la potència generada pels parcs eòlics en les respostes transitòries i estacionàries dels diferents corrents i tensions.
Categories: Novetats

Anàlisi i optimització d'un procés de producció de detergents a nivell industrial

dt., 02/13/2018 - 18:52
Anàlisi i optimització d'un procés de producció de detergents a nivell industrial Diaz Gonzalez, Alejandro
Categories: Novetats

Producció d'ACS d'una piscina municipal coberta mitjançant energia solar tèrmica

dt., 02/13/2018 - 18:45
Producció d'ACS d'una piscina municipal coberta mitjançant energia solar tèrmica Lopez Asensio, Daniel Aquest projecte estudia la viabilitat d’implantació d’una instal·lació solar tèrmica en una instal·lació esportiva existent, situada al municipi de l’Hospitalet de l’Infant. Concretament, aquesta instal·lació solar ha de cobrir un percentatge important de la demanda d’aigua calenta sanitària dels tres vasos situats a les instal·lacions, per tal de reduir la dependència de combustibles fòssils (gas natural). L’equip instal·lat actualment consisteix en dues calderes de gas natural, les quals passarien a tenir un paper d’equipament auxiliar. Primerament s’estudia la situació geogràfica de les instal·lacions, per poder saber les condicions climatològiques que suporta i determinar de manera qualitativa el potencial que tenen per a instal·lar-hi captadors solars. A continuació es realitza un estudi dels tancaments que envolten la sala dels tres vasos. Amb els resultats obtinguts es calculen a continuació les pèrdues tèrmiques que supleixen actualment les dues calderes de gas natural. Una vegada s’han quantificat les pèrdues de potència calorífica, es dimensiona la instal·lació solar mitjançant el mètode f-chart. Aquest ens permet també saber quina serà la fracció de la demanda coberta per les plaques solars. Es proposen tres solucions, però s’estudien només les dues viables. Per últim, es fa una anàlisi econòmica de les dues solucions viables per tal d’escollir-ne la millor i es fa un petit estudi mediambiental de la reducció d’emissions que comportaria l’ús de la instal·lació dissenyada. La solució trobada consisteix en un camp solar amb 180 captadors que permeten cobrir el 58,87% de la demanda d’aigua calenta sanitària dels tres vasos.
Categories: Novetats

Pharmacokinetics in morbid obesity: influence of two bariatric surgery techniques on paracetamol and caffeine metabolism

dt., 02/13/2018 - 15:15
Pharmacokinetics in morbid obesity: influence of two bariatric surgery techniques on paracetamol and caffeine metabolism Goday Arno, Albert; Farré, Magí; Rodriguez Morato, Jose; Ramon, Jose M.; Perez Maña, Clara; Papaseit, Esther; Civit, Ester; Langohr, Klaus; Li Carbo, Marcel; De la Torre Fornell, Rafael The purpose of the study was to study the impact of the two most common bariatric surgery techniques on paracetamol pharmacokinetics (a marker of gastric emptying) and caffeine metabolism (a marker of liver function). In the present prospective study, we studied 24 morbid obese patients before, at 4 weeks, and 6 months after having undergone sleeve gastrectomy (n = 10) or Roux-en-Y gastric bypass (n = 14). For comparative purposes, 28 healthy controls (14 normal weights and 14 overweights) were also included in the study. Paracetamol pharmacokinetics was altered in the obese participants leading to lower bioavailability. Bariatric surgery resulted in faster absorption and normalized pharmacokinetic parameters, prompting an increase in paracetamol bioavailability. No differences were found between surgical procedures. In the case of caffeine, the ratio paraxanthine/caffeine did not differ between morbid obese and healthy individuals. This ratio remained unmodified after surgery, indicating that the liver function (assessed by cytochrome P450 1A2 activity) was unaffected by obesity or bariatric surgery. Paracetamol pharmacokinetics and caffeine plasma levels are altered in severely obese patients. The two studied bariatric surgical techniques normalize paracetamol oral bioavailability without impairing the liver function (measured by cytochrome P450 1A2 activity).
Categories: Novetats

An architecture to support autonomic slice networking

dt., 02/13/2018 - 14:23
An architecture to support autonomic slice networking Velasco Esteban, Luis Domingo; Gifre, Lluís; Izquierdo Zaragoza, Jose Luis; Paolucci, Francesco; Vela, Alba P.; Sgambelluri, Andrea; Ruiz Ramírez, Marc; Cugini, Filippo IEEE Network slices combine resource virtualization with the isolation level required by future 5G applications. In addition, the use of monitoring and data analytics help to maintain the required network performance, while reducing total cost of ownership. In this paper, an architecture to enable autonomic slice networking is presented. Extended nodes make local decisions close to network devices, whereas centralized domain systems collate and export metered data transparently to customer controllers, all of them leveraging customizable and isolated data analytics processes. Discovered knowledge can be applied for both proactive and reactive network slice reconfiguration, triggered either by service providers or customers, thanks to the interaction with state-of-the-art software-defined networking controllers and planning tools. The architecture is experimentally demonstrated by means of a complex use case for a multi-domain multilayer MPLS-over-optical network. In particular, the use case consists of the following Observe-Analyze-Act loops: i) proactive network slice rerouting after BER degradation detection in a lightpath supporting a virtual link (vlink); ii) reactive core network restoration after optical link failure; and iii) reactive network slice rerouting after the degraded lightpath is restored. The proposed architecture is experimentally validated on a distributed testbed connecting premises in UPC (Spain) and CNIT (Italy).
Categories: Novetats

Report on the EGNSS competition after Y2

dt., 02/13/2018 - 13:40
Report on the EGNSS competition after Y2 Sanz Subirana, Jaume; Juan Zornoza, José Miguel; Alonso Alonso, María Teresa; Povero, Gabriella
Categories: Novetats

Meeting the requirements to deploy cloud RAN over optical networks

dt., 02/13/2018 - 12:20
Meeting the requirements to deploy cloud RAN over optical networks Velasco Esteban, Luis Domingo; Castro Casales, Alberto; Asensio Garcia, Adrian; Ruiz Ramírez, Marc; Liu, G.; Qin, C.; Proietti, Roberto; Yoo, Sung-Joo Ben Radio access network (RAN) cost savings are expected in future cloud RAN (C-RAN). In contrast to traditional distributed RAN architectures, in C-RAN, remote radio heads (RRHs) from different sites can share baseband processing resources from virtualized baseband unit pools placed in a few central locations (COs). Due to the stringent requirements of the several interfaces needed in C-RAN, optical networks have been proposed to support C-RAN. One of the key elements that needs to be considered are optical transponders. Specifically, sliceable bandwidth-variable transponders (SBVTs) have recently shown many advantages for core optical transport networks. In this paper, we study the connectivity requirements of C-RAN applications and conclude that dynamicity, fine granularity, and elasticity are needed. However, there is no SBVT implementation that supports those requirements, and thus, we propose and assess an SBVT architecture based on dynamic optical arbitrary generation/measurement. We consider different long-term evolution-advanced configurations and study the impact of the centralization level in terms of the capital expense and operating expense. An optimization problem is modeled to decide which COs should be equipped and which equipment, including transponders, needs to be installed. The results show noticeable cost savings from installing the proposed SBVTs compared to installing fixed transponders. Finally, compared to the maximum centralization level, remarkable cost savings are shown when a lower level of centralization is considered.
Categories: Novetats

Informational analysis of international university rankings

dt., 02/13/2018 - 11:59
Informational analysis of international university rankings Gallofré Ocaña, Marc This work on the informational analysis of international rankings is motivated by the fact that international university rankings are increasing their impact and importance. Given their diversity of origins, purposes and procedures, it makes sense to try to increase their knowledge and understanding by clearly defining and comparing them from an informational stance. This research-orientated master thesis (master final project or TFM) addresses this purpose, by aiming at a clear and comparative definition of both the information managed by those rankings, as well as their respective processes for capturing, processing and publishing their results. These comparative definitions are carried using the Method for informational analysis of university rankings derived and designed from the experience of pursing the analysis work within this master thesis. At the same time, this method allows to assess transparency on rankings and helps to clarify the focus of the information used for rank universities.
Categories: Novetats

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