773 research outputs found

    Gas turbine size optimization in a hybrid system considering SOFC degradation

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    The coupling of a pressurized solid oxide fuel cell (SOFC) and a gas turbine has been proven to result in extremely high efficiency and reduced emissions. The presence of the gas turbine can improve system durability compared to a standalone SOFC, because the turbomachinery can supply additional power as the fuel cell degrades to meet the power request. Since performance degradation is an obstacles to SOFC systems commercialization, the optimization of the hybrid system to mitigate SOFC degradation effects is of great interest. In this work, an optimization approach was used to innovatively study the effect of gas turbine size on system durability for a 400 kW fuel cell stack. A larger turbine allowed a bigger reduction in SOFC power before replacing the stack, but increased the initial capital investment and decreased the initial turbine efficiency. Thus, the power ratio between SOFC and gas turbine significantly influenced system economic results

    Design of a Base-Board for arrays of closely-packed Multi-Anode Photo-Multipliers

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    We describe the design of a Base-Board to house Multi-Anode Photo-Multipliers for use in large-area arrays of light sensors. The goals, the design, the results of tests on the prototypes and future developments are presented.Comment: 16 pages, 5 figures, submitted to Nucl. Instrum. and Meth.

    Microwave apparatus for gravitational waves observation

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    In this report the theoretical and experimental activities for the development of superconducting microwave cavities for the detection of gravitational waves are presented.Comment: 42 pages, 28 figure

    The orbital period, black hole mass and distance to the X-ray transient GRS 1716-249 (=N Oph 93)

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    We present evidence for a 0.278(8) d (=6.7 h) orbital period in the X-ray transient GRS 1716-249 (=N Oph 93), based on a superhump modulation detected during the 1995 mini-outburst plus ellipsoidal variability in quiescence. With a quiescent magnitude of r=23.19+-0.15 N Oph 93 is too faint to warrant a full dynamical study through dedicated time-resolved spectroscopy. Instead, we apply the FWHM-K2 correlation to the disc Halpha emission line detected in Gran Telescopio Canarias spectra and obtain K2=521+-52 km/s. This leads to a mass function f(M)=4.1+-1.2 Msun, thus indicating the presence of a black hole in this historic X-ray transient. Furthermore, from the depth of the Halpha trough and the quiescent light curve we constrain the binary inclination to i=61+-15 deg, while the detection of superhumps sets an upper limit to the donor to compact star mass ratio q=M2/M1<=0.25. Our de-reddened (r-i) colour is consistent with a ~K6 main sequence star that fills its Roche lobe in a 0.278 d orbit. Using all this information we derive a compact object mass M1=6.4+3.2-2.0 Msun at 68 per cent confidence. We also constrain the distance to GRS 1716-249 to 6.9+-1.1 kpc, placing the binary ~0.8 kpc above the Galactic Plane, in support of a large natal kick.Comment: Accepted for publication in MNRAS, 12 pages, 9 figures, 2 Table

    Preterm Infants’ Follow-Up Program at a Public Hospital in Buenos Aires: Two-Decade Study

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    Objectives: To analyze temporal trends of mortality, morbidity, growth and neurodevelopment until 2 years of corrected age (CA) of very low birth weight infants (VLBWI) born between 1986- 2005 in Ramon Sardá Maternal Infant Hospital (RSMIH). Methods: Descriptive temporal trend study divided in 5 quinquenniums.1255 VLBWI were born at RSMIH between 1986-2005; 46 were excluded (genetic syndromes, major congenital malformations, confirmed intrauterine infections), 84 were referred out and 1125 were studied. Birth weight (BW), gestational age (GA); morbidity; growth; neurodevelopment at 1 and 2 years of CA; neurological and sensorial disorders, antenatal steroids use, breastfeeding; rehospitalizations; mothers® age and years of schooling and Unsatisfied Basic Needs Index (UBNI) were recorded. Results: Survival rates increased during the last two periods, especially in &lt;1000g BW infants despite the decrease in GA and BW. Children receiving surfactant (Sf), parenteral nutrition (PN) and antenatal steroids (AS) in the last quinquennium obtained better results in growth (40 weeks GA and 1 CA). The use of these therapies increased greatly in the last decade. Also breastfeeding at 40 weeks GA and 4 months tended to be better. Bronchopulmonary dysplasia (BPD) increased. Rehospitalizations (majorly attributable to lower tract infections) and UBNI stayed equal all along. Mothers’ years of schooling increased a little in the last two quinquenniums. Conclusion: In the last quinquennium children tended to be smaller in GA and BW due to an increase in the survival rate as a result of higher technology and appropriate interventions such as AS, PN, Sf, etc

    Prognosis of follicular lymphoma: a predictive model based on a retrospective analysis of 987 cases

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    Patients (n-987) with a histologically confirmed diagnosis of follicular lymphoma were studied with the aim of developing a prognostic model specifically devised for this type of lymphoma. We collected information on age, sex, Ann Arbor stage, number of extranodal disease sites, bone marrow (BM) involvement, bulky disease, B symptom criteria (fever, night sweats, and weight loss), performance status (PS), serum lactate dehydrogenase (LDH) level, serum albumin level, hemoglobin level, and erythrocyte sedimentation rate (ESR). In the training sample of 429 patients with complete data, multivariate analysis showed that age, sex, number of extranodal sites, B symptoms, serum LDH level, and ESR were factors predictive for overall survival. Using these 6 variables, a prognostic model was devised to identify 3 groups at different risk. The 5- and 10-year survival rate was 90% and 65% for patients at low risk, respectively; 75% and 54% for patients at intermediate risk; and 38% and 11% for those at high risk (log-rank test, 86.62; P < .0001). The model was also predictive (P = .0001) in the validation sample of 265 patients with complete data only for the 6 variables used in the development of the model and even in the group of 210 patients from the validation sample uniformly treated with doxorubicin-containing regimens (P = .0001). The prognostic model appears to be very useful in identifying patients with follicular lymphoma at low, intermediate, or high risk

    NEMO: A Project for a km3^3 Underwater Detector for Astrophysical Neutrinos in the Mediterranean Sea

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    The status of the project is described: the activity on long term characterization of water optical and oceanographic parameters at the Capo Passero site candidate for the Mediterranean km3^3 neutrino telescope; the feasibility study; the physics performances and underwater technology for the km3^3; the activity on NEMO Phase 1, a technological demonstrator that has been deployed at 2000 m depth 25 km offshore Catania; the realization of an underwater infrastructure at 3500 m depth at the candidate site (NEMO Phase 2).Comment: Proceeding of ISCRA 2006, Erice 20-27 June 200

    A cross validation of Consumer-Based Brand Equity (CBBE) with Private Labels in Spain

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    Molinillo,S., Ekinci, Y., Japutra, A. (2014)'A cross validation of Consumer-Based Brand Equity (CBBE) with Private Labels in Spain'. in Martínez-López, Gázquez-Abad, J.C. and Sethuraman, R. J.A. (eds.) Advances in National Brand and Private Label Marketing. Second International Conference, 2015. Springer Proceedings in Business and Economics, pp. 113-125In recent years a number of Consumer-Based Brand Equity (CBBE) models and measurement scales have been introduced in the branding literature. However, examinations of brand equity in Private Labels (PL) are rather limited. This study aims to compare the validity of the two prominent CBBE models those introduced by Yoo and Donthu (2001) and Nam et al. (2011). In order to test the models and make this comparison, the study collected data from 236 respondents who rated private labels in Spain. A list of 30 different fashion and sportswear PL was introduced to respondents. These brands do not make any reference to the retail store in which they are sold. Research findings suggest that the extended CBBE model introduced by Nam et al. (2011) and Ciftci et al. (2014) is more reliable and valid than Yoo and Donthu’s model for assessing PL. Theoretical contributions and managerial implications are discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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