Adjustable speed operation of a hydropower plant associated to an irrigation reservoir

This paper deals with the issue of adjustable speed operation (ASO) of hydropower plants. The main idea of this technique is to allow the turbine speed to change in accordance with hydraulic conditions, thus improving the overall unit efficiency. General technical aspects of ASO are further discussed with special emphasis on the energy and operational benefits that may potentially result from its application. In order to assess these benefits, annual operation of a hydropower plant associated to an irrigation reservoir has been simulated under different scenarios, with both adjustable and fixed speed. Turbine operating range proved to be wider with ASO. In addition, simulation results confirm that considerable energy gains are expected to be obtained

Role of Olive Oil and Monounsaturated Fatty Acids in Mitochondrial Oxidative Stress and Aging

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Architecture extensions for efficient managament of scratch-pad Memory

Nowadays, many embedded processors include in their architecture on-chip static memories, so called scratch-pad memories (SPM). Compared to cache, these memories do not require complex control logic, thus resulting in increased efficiency both in silicon area and energy consumption. Last years, many papers have proposed algorithms to allocate memory segments in SPM in order to enhance its usage. However, very few care about the SPM architecture itself, to make it more controllable, more power efficient and faster. This paper proposes architecture extensions to automatically load code into the SPM whilst it is fetched for execution to reduce the SPM updating delays, which motivates a very dynamic use of the SPM. We test our proposal in a derivation of the Simplescalar simulator, with typical embedded benchmarks. The results show improvements, on average, of 30.6% in energy saving and 7.6% in performance compared to a system with cache. © 2011 Springer-Verlag.This research was sponsored by local Government “Generalitat Valenciana” under project GV07/ 2007/122.Busquets Mataix, JV.; Catalá, C.; Martí Campoy, A. (2011). Architecture extensions for efficient managament of scratch-pad Memory. En Integrated Circuit and System Design. Power and Timing Modeling, Optimization, and Simulation. Springer Verlag (Germany). (6951):43-52. https://doi.org/10.1007/978-3-642-24154-3_5S43526951Banakar, R., Steinke, S., Lee, B.-S., Balakrishnan, M., Marwedel, P.: Scratchpad memory: design alternative for cache on-chip memory in embedded systems. In: CODES 2002, pp. 73–78 (2002)Verma, M., Wehmeyer, L., Marwedel, P.: Cache-Aware Scratchpad Allocation Algorithm. In: DATE 2004, pp. 1264–1269 (2004)Verma, M., Marwedel, P.: Advanced memory optimization techniques for low-power embedded processors, pp. I-XII, 1–188. Springer, Heidelberg (2007)Nguyen, N., Dominguez, A., Barua, R.: Memory allocation for embedded systems with a compile-time-unknown scratch-pad size. In: CASES 2005, pp. 115–125 (2005)Egger, B., Kim, C., Jang, C., Nam, Y., Lee, J., Min, S.L.: A dynamic code placement technique for scratchpad memory using postpass optimization. In: CASES 2006, pp. 223–233 (2006)Egger, B., Lee, J., Shin, H.: Scratchpad memory management for portable systems with a memory management unit. In: EMSOFT 2006, pp. 321–330 (2006)Egger, B., Lee, J., Shin, H.: Dynamic scratchpad memory management for code in portable systems with an MMU. ACM Trans. Embedded Comput. Syst. 7(2) (2008)Cho, H., Egger, B., Lee, J., Shin, H.: Dynamic data scratchpad memory management for a memory subsystem with an MMU. In: LCTES 2007, pp. 195–206 (2007)Janapsatya, A., Parameswaran, S., Ignjatovic, A.: Hardware/software managed scratchpad memory for embedded system. In: ICCAD 2004, pp. 370–377 (2004)Balakrishnan, M., Marwedel, P., Wehmeyer, L., Grunwald, N., Banakar, R., Steinke, S.: Reducing Energy Consumption by Dynamic Copying of Instructions onto Onchip Memory. In: ISSS 2002, pp. 213–218 (2002)Poletti, F., Marchal, P., Atienza, D., Benini, L., Catthoor, F., Mendias, J.M.: An integrated hardware/software approach for run-time scratchpad management. In: DAC 2004, pp. 238–243 (2004)Li, L., Gao, L., Xue, J.: Memory Coloring: A Compiler Approach for Scratchpad Memory Management. In: IEEE PACT 2005, pp. 329–338 (2005)Lee, L.H., Moyer, B., Arends, J.: Instruction fetch energy reduction using loop caches for embedded applications with small tight loops. In: ISLPED 1999, pp. 267–269 (1999)Victorio, J.A., Torres Moren, E.F., Yúfera, V.V.: Vatios: Simulador de Procesador con Estimación de Potencia. XVIII Jornadas de Paralelismo, Zaragoza (2007)Burger, D., Austin, T.M.: The SimpleScalar Tool Set Version 2.0. Technical Report 1342, Computer Sciences Department. University of Wisconsin–Madison (May 1997)Brooks, D., Tiwari, V., Martonosi, M.: Wattch: a framework for architectural-level power analysis and optimizations. In: ISCA 2000, pp. 83–94 (2000)Tarjan, D., Thoziyoor, S., Jouppi, N.: CACTI 4.0, P. HPL-2006- 86 20060606The Mälardalen WCET research group. The Mälardalen WCET benchmarks homepage, http://www.mrtc.mdh.se/projects/wcet/benchmarks.htmlCho, D., Pasricha, S., Issenin, I., Dutt, N.D., Ahn, M., Paek, Y.: Adaptive Scratch Pad Memory Management for Dynamic Behavior of Multimedia Applications. IEEE Trans. on CAD of Integrated Circuits and Systems (TCAD) 28(4), 554–567 (2009

Grabados rupestres del Cantalar (Tibi, Alicante)

El presente artículo pretende dar a conocer una serie de conjuntos de grabados rupestres aparecidos en el término municipal de Tibi (Alicante). Éstos comparten estructura básica, si no funcionalidad, con los observados en muchos enclaves de toda la fachada mediterránea y el interior de la Península Ibérica. Se trata por un lado de cazoletas de reducido tamaño a las cuáles vierten canalillos de distintas morfologías, apareciendo algunas de ellas en el contexto de un poblado de la Edad del Bronce. Por otro lado encontramos motivos cruciformes, los cuales asociamos a momentos históricos.This paper tries to present a set of rock engravings appeared in Tibi (Alicante). They share basic structure, if not functionality, with those observed in many locations throughout the Mediterranean facade and interior of the Iberian Peninsula. Those are, on the one hand, small cupules carved in the rock to what dumped gutters of different morphologies, some of them appearing in the context of a settlement of the Bronze Age. On the other hand we find cruciform motifs, which we associate with historical moments

International cooperation for developmen: Design of a competence-based model for managing programmes and projects

Managing international cooperation for development projects is a complex task that involves technical, political, socio-economic and cultural variables. The technical, contextual and performance competences of those who manage these kinds of projects must take this complexity as their starting point and tackle it with all their accumulated experience to decide what actions need to be carried out. This research includes an analysis of the theory and application of the project management methodologies currently used by development organisations; an analysis that takes a critical look at the success or failure of development interventions, assessing the components of competences and the essential skills for project managers. It also examines how proposals for cooperation project management methodology are drawn up, specifi c training programmes in this area, the coordination between players, and knowledge management, with the purpose of enhancing the impact of development intervention

Síndrome d'Acumulació Compulsiva: "M'ho guardo. No sigui cas que..."

El 50% de les persones que pateixen aquesta síndrome no presenten un quadre de Transtorn Obsessiu Compulsiu. Una dada clau per entendre més a fons una variant poc estudiada i que cal diferenciar de la síndrome de Diògenes. Es tracta de persones de qualsevol edat, majoritàriament dones, que els resulta difícil desprendre's d'objectes sense valor i amb els que, en gran part dels casos, estableixen un vincle emocional. Una situació que deriva en espais inhabitables de la llar i condiciona el dia a dia del pacient. El següent estudi, encapçalat pel Departament de Psiquiatria de l'Hospital de Bellvitge, i amb la col·laboració de l'Institute of Psychiatry de Londres, obre el camí per continuar investigant. De moment, el mes d'octubre passat, l'article va ser publicat a la revista American Journal of Psychiatry.El 50% de las personas que sufren este síndrome no presentan un cuadro de Trastorno Obsesivo Compulsivo. Un dato clave para entender más a fondo una variante poco estudiada y que hay que diferenciar del síndrome de Diógenes. Se trata de personas de cualquier edad, mayoritariamente mujeres, que les resulta difícil desprenderse de objetos sin valor y con los que, en gran parte de los casos, establecen un vínculo emocional. Una situación que deriva en espacios inhabitables del hogar y condiciona el día a día del paciente. El siguiente estudio, encabezando por el Departamento de Psiquiatría del Hospital de Bellvitge, y con la colaboración de l'Institute of Psychiatry de Londres, abre el camino para continuar investigando. De momento, el pasado mes de octubre, el artículo fue publicado en la revista American Journal of Psychiatry

Reflexiones en torno a los enterramientos de la Edad del Bronce en las tierras valencianas. A propósito de la Cova de l’Esbarzer (la Vall de Gallinera, Alacant)

Con ocasión de una reciente síntesis sobre la Edad del Bronce en el Comtat (Hernández y Mataix, 2015) tuvimos ocasión de estudiar los yacimientos y materiales adscritos a esta etapa de nuestra Prehistoria que a lo largo de varias décadas de trabajos de campo miembros del Centre d’Estudis Contestans –C.E.C.- han depositado, junto a la documentación correspondiente, en el Museu Arqueològic i Etnològic del Comtat, en Cocentaina (Ferrer, 2002). Con la ayuda inestimable de Pere Ferrer i Marset, que participó activamente en todas aquellas actuaciones arqueológicas, tuvimos conocimiento de primera mano de los trabajos realizados en los yacimientos que en el registro del museo se identifican como de la Edad del Bronce y se localizan en las tierras montañosas de la actual provincia de Alicante, incluidas en el Prebético Meridional Valenciano, sobre la que en estos momento se última su estudio

Stiffness variation of porous titanium developed using space holder method

The excellent properties of Ti have resulted in its generalised use for bone implants. However, Ti is very stiff in comparison with human cortical bone, and this creates problems of bone weakening and loosening of the implant. This article discusses the mechanical properties (flexural and compressive strength, and stiffness) of porous Ti-6Al-4V specimens developed using the space holder method. These properties are examined relative to the production process parameters: compacting pressure and sintering time, as well as temperature, and the addition of spacer and its particle size. It is seen that when spacer is added, compressive strength decreases with the application of compacting pressure and that these are the most influential parameters. The developed pieces show a closed and unconnected porosity. Small additions of spacer (25 vol.-%) reduce stiffness to around half of that shown by the solid material, and the resulting pieces are strong enough to be used as bone substitute. © 2011 Institute of Materials, Minerals and Mining.The authors wish to thank the Spanish Ministry of Science and Innovation for the support received under project no. PET2008_0158_02. The translation of this article was funded by the Universidad Politecnica de Valencia.Reig Cerdá, L.; Amigó Borrás, V.; Busquets Mataix, DJ.; Calero, JA. (2011). Stiffness variation of porous titanium developed using space holder method. Powder Metallurgy. 54(3):389-392. https://doi.org/10.1179/003258910X12707304455068S389392543RYAN, G., PANDIT, A., & APATSIDIS, D. (2006). Fabrication methods of porous metals for use in orthopaedic applications. Biomaterials, 27(13), 2651-2670. doi:10.1016/j.biomaterials.2005.12.002in ‘ASM handbook’, Vol. 2, ‘Properties and selection: nonferrous alloys and special-purpose materials’, 1170; 1990, Materials Park, OH, ASM International.Asaoka, K., & Kon, M. (2003). Sintered Porous Titanium and Titanium Alloys as Advanced Biomaterials. Materials Science Forum, 426-432, 3079-3084. doi:10.4028/www.scientific.net/msf.426-432.3079Niinomi, M. (2008). Mechanical biocompatibilities of titanium alloys for biomedical applications. Journal of the Mechanical Behavior of Biomedical Materials, 1(1), 30-42. doi:10.1016/j.jmbbm.2007.07.001Rack, H. J., & Qazi, J. I. (2006). Titanium alloys for biomedical applications. Materials Science and Engineering: C, 26(8), 1269-1277. doi:10.1016/j.msec.2005.08.032Köhl M, Bram M, Buckremer HP, Stöver D: Proc. Conf. Euro PM2007, Toulouse, France, October 2007, European Powder Metallurgy Association, 129–134.Bram M, Bogdanski SH, Koller M, Buchkremer HP, Stover D: Proc. Conf. Euro PM2005, Prague, Czech Republic, October 2005, European Powder Metallurgy Association, 517–522.Reig L, Amigó V, Busquets D, Salvador MD, Calero JA: Proc. Conf. Sintering 2008, La Jolla, CA, USA, November 2008, American Ceramic Society. 273–282.Degischer, H., & Kriszt, B. (Eds.). (2002). Handbook of Cellular Metals. doi:10.1002/3527600558Comín M, Peris JL, Prat JM, Decoz JR, Vera PM, JV: Hoyos: ‘Biomecánica de la fractura ósea y técnicas de reparación’, 66–69; 1999, Valencia, Publicaciones UPV.Gibson LJ, Ashby MF: ‘Cellular solids: structure and properties’, 175–231; 1999, Cambridge, Cambridge University Press.Making metal foams. (2000). Metal Foams, 6-23. doi:10.1016/b978-075067219-1/50004-0Esen, Z., & Bor, Ş. (2007). Processing of titanium foams using magnesium spacer particles. Scripta Materialia, 56(5), 341-344. doi:10.1016/j.scriptamat.2006.11.010Leyens, C., & Peters, M. (Eds.). (2003). Titanium and Titanium Alloys. doi:10.1002/3527602119Lütjering G, Williams JC: ‘Titanium’, 2nd edn, 13–51; 2007, Berlin, Springer, Engineering Materials and Processes