Universitat Politècnica de València

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    Synthetic 3D Pap smear nucleus generation

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    Gómez Aguilar, S. (2010). Synthetic 3D Pap smear nucleus generation. http://hdl.handle.net/10251/10215

    Optimal boundary geometry in an elasticity problem: a systematic adjoint approach

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    p. 509-524In different problems of Elasticity the definition of the optimal geometry of the boundary, according to a given objective function, is an issue of great interest. Finding the shape of a hole in the middle of a plate subjected to an arbitrary loading such that the stresses along the hole minimizes some functional or the optimal middle curved concrete vault for a tunnel along which a uniform minimum compression are two typical examples. In these two examples the objective functional depends on the geometry of the boundary that can be either a curve (in case of 2D problems) or a surface boundary (in 3D problems). Typically, optimization is achieved by means of an iterative process which requires the computation of gradients of the objective function with respect to design variables. Gradients can by computed in a variety of ways, although adjoint methods either continuous or discrete ones are the more efficient ones when they are applied in different technical branches. In this paper the adjoint continuous method is introduced in a systematic way to this type of problems and an illustrative simple example, namely the finding of an optimal shape tunnel vault immersed in a linearly elastic terrain, is presented.Garcia-Palacios, J.; Castro, C.; Samartin, A. (2009). Optimal boundary geometry in an elasticity problem: a systematic adjoint approach. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/654

    Ultracompact electro-optic phase modulator based on III-V-on-silicon microdisk resonator

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    This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.37.002379. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.[EN] A novel ultracompact electro-optic phase modulator based on a single 9 ¥ìm-diameter III-V microdisk resonator heterogeneously integrated on and coupled to a nanophotonic waveguide is presented. Modulation is enabled by effective index modification through carrier injection. Proof-of-concept implementation involving binary phase shift keying modulation format is assembled. A power imbalance of ¡-0.6  dB between both symbols and a modulation rate up to 1.8 Gbps are demonstrated without using any special driving technique.The authors gratefully acknowledge the financial support given by the European Seventh Framework Programme through the projects GOSPEL, WADIMOS, and HISTORIC; the Generalitat Valenciana through the Microwave Photonics Excellency Award programme GVA PROMETEO 2008/092; and also the Plan Nacional I+D TEC2011-29120-C05-05 and TEC2008-06145.Lloret Soler, JA.; Kumar, R.; Sales Maicas, S.; Ramos Pascual, F.; Morthier, G.; Mechet, P.; Spuesens, T.... (2012). Ultracompact electro-optic phase modulator based on III-V-on-silicon microdisk resonator. Optics Letters. 37(12):2379-2381. https://doi.org/10.1364/OL.37.002379237923813712Wooten, E. L., Kissa, K. M., Yi-Yan, A., Murphy, E. J., Lafaw, D. A., Hallemeier, P. F., … Bossi, D. E. (2000). A review of lithium niobate modulators for fiber-optic communications systems. IEEE Journal of Selected Topics in Quantum Electronics, 6(1), 69-82. doi:10.1109/2944.826874Li, Y., Wang, R., Bhardwaj, A., Ristic, S., & Bowers, J. (2010). High Linearity InP-Based Phase Modulators Using a Shallow Quantum-Well Design. IEEE Photonics Technology Letters, 22(18), 1340-1342. doi:10.1109/lpt.2010.2054076Png, C. E., Chan, S. P., Lim, S. T., & Reed, G. T. (2004). Optical Phase Modulators for MHz and GHz Modulation in Silicon-On-Insulator (SOI). Journal of Lightwave Technology, 22(6), 1573-1582. doi:10.1109/jlt.2004.827655Chiu, W.-C., Chang, C.-C., Wu, J.-M., Lee, M.-C. M., & Shieh, J.-M. (2011). Optical phase modulators using deformable waveguides actuated by micro-electro-mechanical systems. Optics Letters, 36(7), 1089. doi:10.1364/ol.36.001089Lin, Y.-H., & Tsou, Y.-S. (2011). A polarization independent liquid crystal phase modulation adopting surface pinning effect of polymer dispersed liquid crystals. Journal of Applied Physics, 110(11), 114516. doi:10.1063/1.3666053Kim, S.-K., Yuan, W., Geary, K., Hung, Y.-C., Fetterman, H. R., Lee, D.-G., … Oh, I. (2005). Electro-optic phase modulator using metal-defined polymer optical waveguide. Applied Physics Letters, 87(1), 011107. doi:10.1063/1.1991998Soref, R., & Bennett, B. (1987). Electrooptical effects in silicon. IEEE Journal of Quantum Electronics, 23(1), 123-129. doi:10.1109/jqe.1987.1073206Espinola, R. L., Tsai, M. C., Yardley, J. T., & Osgood, R. M. (2003). Fast and low-power thermooptic switch on thin silicon-on-insulator. IEEE Photonics Technology Letters, 15(10), 1366-1368. doi:10.1109/lpt.2003.818246Feng, N.-N., Liao, S., Feng, D., Dong, P., Zheng, D., Liang, H., … Asghari, M. (2010). High speed carrier-depletion modulators with 14V-cm V_πL integrated on 025μm silicon-on-insulator waveguides. Optics Express, 18(8), 7994. doi:10.1364/oe.18.007994Xu, Q., Schmidt, B., Pradhan, S., & Lipson, M. (2005). Micrometre-scale silicon electro-optic modulator. Nature, 435(7040), 325-327. doi:10.1038/nature03569Xu, Q., Manipatruni, S., Schmidt, B., Shakya, J., & Lipson, M. (2007). 125 Gbit/s carrier-injection-based silicon micro-ring silicon modulators. Optics Express, 15(2), 430. doi:10.1364/oe.15.000430Kuo, Y., Chen, H.-W., & Bowers, J. E. (2008). High speed hybrid silicon evanescent electroabsorption modulator. Optics Express, 16(13), 9936. doi:10.1364/oe.16.009936Hui-Wen Chen, Ying-Hao Kuo, & Bowers, J. E. (2008). A Hybrid Silicon–AlGaInAs Phase Modulator. IEEE Photonics Technology Letters, 20(23), 1920-1922. doi:10.1109/lpt.2008.2004790Van Campenhout, J., Romeo, P. R., Van Thourhout, D., Seassal, C., Regreny, P., Di Cioccio, L., … Baets, R. (2008). Design and Optimization of Electrically Injected InP-Based Microdisk Lasers Integrated on and Coupled to a SOI Waveguide Circuit. Journal of Lightwave Technology, 26(1), 52-63. doi:10.1109/jlt.2007.912107Van Thourhout, D., Spuesens, T., Selvaraja, S. K., Liu, L., Roelkens, G., Kumar, R., … Grenouillet, L. (2010). Nanophotonic Devices for Optical Interconnect. IEEE Journal of Selected Topics in Quantum Electronics, 16(5), 1363-1375. doi:10.1109/jstqe.2010.2040711Liu, L., Van Campenhout, J., Roelkens, G., Soref, R. A., Van Thourhout, D., Rojo-Romeo, P., … Baets, R. (2008). Carrier-injection-based electro-optic modulator on silicon-on-insulator with a heterogeneously integrated III-V microdisk cavity. Optics Letters, 33(21), 2518. doi:10.1364/ol.33.00251

    Randomness in topological models

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    p. 914-925There are two aspects of randomness in topological models. In the first one, topological idealization of random patterns found in the Nature can be regarded as planar representations of three-dimensional lattices and thus reconstructed in the space. Another aspect of randomness is related to graphs in which some properties are determined in a random way. For example, combinatorial properties of graphs: number of vertices, number of edges, and connections between them can be regarded as events in the defined probability space. Random-graph theory deals with a question: at what connection probability a particular property reveals. Combination of probabilistic description of planar graphs and their spatial reconstruction creates new opportunities in structural form-finding, especially in the inceptive, the most creative, stage.Tarczewski, R.; Bober, W. (2010). Randomness in topological models. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/695

    FEM Analysis Considering stiffness of 3 Stepped Bracket Complex for ENGAKUJI SHARIDEN as a Historical Wooden Structure in Japan

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    p. 476-488Engaku Temple has been built at Kamakura City nearby Yokohama in 1285. The SHARIDEN is one of the facitilies there in order to store the Buddha's bone and has been selected as Japanese national treasure. However, most of the original materials have been lost because of suffering from a fire in 1563. After that, the current SHARIDEN has been replaced by TAIHEI Temple which was also located in Kamakura. In the former study[1], the FEM model for SHARIDEN has been established as a space frame and the linear elastic analyses have also been executed. In the present study, the following targets will be prepared to analyze the structural behaviours in detail. (1) Reconfirm the coordinates of nodal points and member arrangement for the FEM model (2) The structural behaviours of 3 stepped bracket complex has been simulated with 3D FEM solid model to obtain the equivalent frame to the real bracket (3) Estimate more exact distribution of the vertical load on the top and lower roofs (4) Investigate the effect of the deterioration at the joints on the whole structural behaviours by considering bending springs arranged at the both ends of members. The numerical model has been assembled by CAD data originally created basing on the drawings edited by Kanagawa Prefecture. The number of unknowns reaches upto 13,000. The numerical model for 3 stepped bracket has also contains over 10,000 unknowns. Through above investigations, the structural features and several suggestions for reinforcements would be discussed for such an important structure.Takashima, H. (2009). FEM Analysis Considering stiffness of 3 Stepped Bracket Complex for ENGAKUJI SHARIDEN as a Historical Wooden Structure in Japan. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/653

    Timber roof structure for outdoor auditorium in Parque Paraiso, San Blas (Madrid)

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    p. 468-475A timber shell structure is designed to provide covering for an outdoor auditorium in Madrid (Spain). The covering comprises five independent overlapped marquees with similar shape but diverse dimensions. The surface geometry of each marquee is defined by a hyperbolic paraboloid, with its boundaries delimited by elliptical curves in horizontal projection. Structural section for the timber shell is a composite section with several staggered layers of straight sawn timber planks, arranged in two orthogonal directions following the straight skew lines of the hyperbolic paraboloid. Over them two continuous top layers are arranged which provides bracing for the structure and support for the waterproofing material. Each layer is laid over the previous one, bolted and glued with polyurethane adhesive. Special characteristics of the design analysis and detailed erection process are described. The designed solution provides lightweight roofing with a powerful and original image, short construction time and reasonable budget.Anton, A.; Meijide, AG.; Corbal, JJ. (2009). Timber roof structure for outdoor auditorium in Parque Paraiso, San Blas (Madrid). Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/653

    Epizootic rabbit enteropathy. Study of early phenomena with fresh inoculum and attempt at inactivation

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    [EN] Using 180 35-day-old SPF rabbits, this study used the effectiveness of bacitracin as a tool for acquiring more information on the various phases of ERE, in particular during the hours inoculation. Five groups of animals were used, including 3 treatments with Bacivet S(R) (bacitracin) at different times from inoculation, with the standard inoculum TEC3. Three parameters were studied: growth, mortality and stomach noises (borborygmi). A significant fall in growth rate was observed during the first 18 hours following the inoculation in all the inoculated groups, both medicated and not medicated. Treatment with bacitracin eliminated mortality and borborygmi, but not the initial fall in growth rate. Treatment starting 18 hours after inoculation is less effective during the acute phase than the preventive treatment. With a preventive treatment interrupted as soon as 18 hours after inoculation, a delay of several days was observed before the appearance of the disease (fall in growth rate, manifestation of borborygmi) and total mortality was reduced. Very few pathogens can explain this early fall in growth rate. Bacitracin is an antibiotic which offers good control of the disease, and probably of the pathogen but not of the physio-pathological disturbances in the first few hours. The intervention of an exogenic toxin in the first hours of contamination seems likely. Borborygmi are important criteria. The intensity and/or frequency could be used as semi-quantitative criteria to characterize the disease and for the prognosis. In a simultaneous trial, a group was contaminated with the same inoculum, heated for 10 min at 55°C, in order to obtain more information on the type of pathogen involved in the etiology of ERE. This treatment did not modify the virulence of the inoculum.This research received financial help from the Ministry for Agriculture of France (DGAL - ITAVI).Coudert, P.; Licois, D. (2005). Epizootic rabbit enteropathy. Study of early phenomena with fresh inoculum and attempt at inactivation. World Rabbit Science. 13. doi:10.4995/wrs.2005.5151

    Abstracts of the Reproduction section presented during the 8th World Rabbit Congress, Puebla, Mexico 7-10. 2004

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    (2005). Abstracts of the Reproduction section presented during the 8th World Rabbit Congress, Puebla, Mexico 7-10. 2004. World Rabbit Science. 13. doi:10.4995/wrs.2005.5121

    Influence of corona charging in cellular polyethlene film

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    [En] Cellular polymers have recently attracted attention for their property of exhibiting a piezoelectric constant when they are electrically charged. The electrostatic charge generated in the voids by the internal discharges creates and internal macrodipole which is responsible for the piezoelectric effect. Charging by corona discharge is the most used method for cellular polymers. Many works has been published on polypropylene and polyethylene films mainly focused on the required expansion process or on the results obtained for raw cellular materials electrically activated. Our work is based on commercial polyethylene cellular films which have been physically characterized and electrically activated. The effect of thermal treatment, physical uniaxial or biaxial stretching and corona charging was investigated. The new method of corona charging improved the piezoelectric constant under other activation conditions.This work has been developed under the project Intelligent Materials with Mechanical and Electrical Properties interaction (E-MAT)" which has been submitted for funding with reference number IMDEEA/2011/13 to the call of Technological Centers of IMPIVA Network 2011, Strategic development program (action 1, R+D projects) financed by the Generalitat Valenciana through the Instituto de la Mediana y Pequena Empresa Valenciana (IMPIVA) and the European Regional Development Fund (ERDF).Ortega Braña, GE.; Llovera Segovia, P.; Magraner Bella, F.; Quijano Lopez, A. (2011). Influence of corona charging in cellular polyethlene film. Journal of Physics: Conference Series. 301:1-4. https://doi.org/10.1088/1742-6596/301/1/01205414301Fukada, E. (2000). History and recent progress in piezoelectric polymers. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 47(6), 1277-1290. doi:10.1109/58.883516Sessler, G. M., & Hillenbrand, J. (1999). Electromechanical response of cellular electret films. Applied Physics Letters, 75(21), 3405-3407. doi:10.1063/1.125308Hillenbrand, J., & Sessler, G. M. (2000). Piezoelectricity in cellular electret films. IEEE Transactions on Dielectrics and Electrical Insulation, 7(4), 537-542. doi:10.1109/94.868074Paajanen, M., Välimäki, H., & Lekkala, J. (2000). Modelling the electromechanical film (EMFi). Journal of Electrostatics, 48(3-4), 193-204. doi:10.1016/s0304-3886(99)00065-0Gerhard-Multhaupt, R. (2002). Less can be more. Holes in polymers lead to a new paradigm of piezoelectric materials for electret transducers. IEEE Transactions on Dielectrics and Electrical Insulation, 9(5), 850-859. doi:10.1109/tdei.2002.1038668Wegener, M., & Bauer, S. (2005). Microstorms in Cellular Polymers: A Route to Soft Piezoelectric Transducer Materials with Engineered Macroscopic Dipoles. ChemPhysChem, 6(6), 1014-1025. doi:10.1002/cphc.200400517Hillenbrand, J., Behrendt, N., Mohmeyer, N., Altsadt, V., Schmidt, H.-W., & Sessler, G. M. (s. f.). Charge retention in biaxially-oriented polypropylene films containing various additives. 2005 12th International Symposium on Electrets. doi:10.1109/ise.2005.1612375Xiaoqing Zhang, Sessler, G. M., & Hillenbrand, J. (s. f.). Optimization of Piezoelectric Properties of Cellular Polypropylene Films by Repeated Expansion. 2005 12th International Symposium on Electrets. doi:10.1109/ise.2005.161231

    Book review: L'allevamento ecologico del coniglio (Organic rabbit farming)

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    González-Redondo, P. (2011). Book review: L'allevamento ecologico del coniglio (Organic rabbit farming). World Rabbit Science. 19(3). doi:10.4995/wrs.2011.869.19


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