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Average Efficiency (average + efficiency)
Selected AbstractsEfficiency Gaps, Love of Variety and International TradeECONOMICA, Issue 269 2001Catia Montagna We develop a general equilibrium monopolistic competition model of trade with technical heterogeneity among firms and countries. With free entry, technical asymmetries between firms result in the endogenous determination of the equilibrium average efficiency of the industry. We show that trade reduces (increases) the minimum efficiency required to survive in the more (less) efficient country. This has important welfare implications: (1) Contrary to the constant elasticity of substitution homogeneous-firms model, trade affects welfare even when there is no love of variety. (2) There are circumstances in which trade liberalization leads to a loss of consumer welfare. [source] An Efficient Organic-Dye-Sensitized Solar Cell with in situ Polymerized Poly(3,4-ethylenedioxythiophene) as a Hole-Transporting MaterialADVANCED MATERIALS, Issue 20 2010Xizhe Liu In situ polymerized PEDOT is used as hole-transporting material to fabricate dye-sensitized solar cells (DSSCs) with an average efficiency of 6.1% (under 100,mW,cm,2 AM1.5 illumination) using organic D149 dye as the sensitizer. By comparing with Z907-based devices, the excellent light response of D149-sensitized DSSCs is attributed to the broad light absorption, low photoelectron recombination, and good polymer penetration. [source] Effects of machinery-sharing arrangements on farm efficiency: evidence from SwedenAGRICULTURAL ECONOMICS, Issue 5 2010Karin Larsén Machinery-sharing; Partnerships; Data envelopment analysis Abstract The effects of partnerships, in the form of machinery-sharing arrangements, on farm efficiency are analyzed using data for Swedish crop and livestock farms. Efficiency scores are obtained using Data Envelopment Analysis and the findings suggest that efficiency is, on average, higher among partnership farms compared to nonpartnership farms. Moreover, partnership farms that are characterized by the most extensive form of collaboration, that is, that share all machinery with one or several other farms, display the highest average efficiency. In a two-stage procedure in which efficiency determinants are analyzed in the second stage, the bootstrap procedures suggested by Simar and Wilson (2007) are applied in addition to the conventionally used Tobit regression. Participation in partnership arrangements is found to have a positive and statistically significant impact on farm efficiency. [source] A compact dual-band modified T-shaped CPW-fed monopole antennaMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2009R. Sujith Abstract A compact, dual band coplanar waveguide fed modified T-shaped uniplanar antenna is presented. The antenna has resonances at 1.77 and 5.54 GHz with a wide band from 1.47,1.97 GHz and from 5.13,6.48 GHz with an impedance bandwidth of 34% and 26%, respectively. Also the antenna has an average gain of 3 dBi in lower band and 3.5 dBi in higher band with an average efficiency of 90%. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 937,939, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24249 [source] Resistivity and lifetime variation along commercially grown Ga- and B-Doped Czochralski Si ingots and its effect on light-induced degradation and performance of solar cellsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 2 2006V. Meemongkolkiat Abstract A systematic study of the variation in resistivity and lifetime on cell performance, before and after light-induced degradation (LID), was performed along ,900-mm-long commercially grown B- and Ga-doped Czochralski (Cz) ingots. Manufacturable screen-printed solar cells were fabricated and analyzed from different locations on the ingots. Despite the large variation in resistivity (0·57,2·5,,,cm) and lifetime (100,1000,µ,s) in the Ga-doped Cz ingot, the efficiency variation was found to be ,,0·5% with an average efficiency of ,17·1%. No LID was observed in these cells. In contrast to the Ga-doped ingot, the B-doped ingot showed a relatively tight resistivity range (0·87,1·22,,,cm), resulting in smaller spread in lifetime (60,400,µ,s) and efficiency (16·5,16·7%) along the ingot. However, the LID reduced the efficiency of these B-doped cells by about 1·1% absolute. Additionally, the use of thinner substrate and higher resistivity (4·3,,,cm) B-doped Cz was found to reduce the LID significantly, resulting in an efficiency reduction of 0·5,0·6%, as opposed to >1·0% in ,1,,,cm ,17% efficient screen-printed cells. As a result, Ga-doped Cz cells gave 1·5 and 0·7% higher stabilized efficiency relative to 1 and 4·3,,,cm B-doped Cz Si cells, respectively. Copyright © 2005 John Wiley & Sons, Ltd. [source] Thin-film GaAs epitaxial lift-off solar cells for space applicationsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 7 2005J. J. Schermer Abstract In the present work the space compatibility of thin-film GaAs solar cells is studied. These cells are separated from their GaAs substrate by the epitaxial lift-off (ELO) technique and mounted behind a CMG cover glass which at the same time serves as a stable carrier for the thin film cells. In the present initial stage of development these cells have an average efficiency of about 15·4% under AM0 illumination due to not yet optimized grid contacts and anti-reflection coatings. Inspection after irradiation by 1,MeV electrons, thermal vacuum and thermal cycling experiments reveal that degradation of the cells is largely due to delamination and micro-cracking. Based on these results, glass dehydration and adhesive degassing procedures are implemented in the ELO cell processing. As a consequence, even in this premature phase, newly produced cells show a radiation hardness comparable to or better than that of commercially available GaAs cells on Ge substrates and are virtually unaffected by severe thermal cycling. Copyright © 2005 John Wiley & Sons, Ltd. [source] Monitoring Protein Interactions in the Living Cell Through the Fluorescence Decays of the Cyan Fluorescent ProteinCHEMPHYSCHEM, Issue 7 2006Regis Grailhe Dr. Abstract Using fluorescence lifetime microspectroscopy and imaging techniques, we have studied the fluorescence of cyan fluorescent protein (CFP) transiently expressed in HEK-293 cells, in the presence or absence of its fluorescence resonance energy transfer (FRET) partner, yellow fluorescent protein (YFP). When the two proteins are attached through a 27-amino-acid linker, a 33,% average efficiency of intramolecular energy transfer is accurately determined inside the cell. Additionally, we observe a systematic quenching of the CFP fluorescence with increasing levels of protein expression. This quenching cannot be accounted for by formation of the previously described dimer of GFP-related proteins, since its magnitude is unchanged when the fluorescent proteins carry the mutation A206K shown to dissociate this dimer in vitro. Even when the intracellular protein concentration largely exceeds the in vitro dissociation constant of the dimer, self-association remains undetectable, either between free proteins or intramolecularly within the CFP,YFP construct. Instead, the detailed concentration effects are satisfactorily accounted for by a model of intermolecular, concentration-dependent energy transfer, arising from molecular proximity and crowding. In the case of CFP alone, we suggest that self-quenching could result from a pseudo-homo FRET mechanism between different, spectrally shifted emissive forms of the protein. These phenomena require careful consideration in intracellular FRET studies. [source] Correlation between severity of mucopolysaccharidoses and combination of the residual enzyme activity and efficiency of glycosaminoglycan synthesisACTA PAEDIATRICA, Issue 4 2009Ewa Piotrowska Abstract Aim: To develop a method for prediction of severity and clinical course of mucopolysaccharidoses (MPS), a group of inherited metabolic diseases. Methods: Various biochemical and clinical parameters (including estimation of the level of clinical severity, presence of specific mutations, residual enzyme activity, urinary glycosaminoglycan (GAG) excretion, storage of GAG in fibroblasts and efficiency of GAG synthesis) of patients suffering from MPS types II, IIIA and IIIB were determined. Correlations between genetic, biochemical and clinical parameters were tested. Results: We found that efficiency of GAG synthesis may contribute to the level of severity of MPS. It appears that (i) combination of low or average efficiency of GAG synthesis and the presence of residual activity of the enzyme is responsible for an attenuated phenotype, (ii) a lack of detectable residual enzyme activity causes a severe phenotype, irrespective of the efficiency of GAG synthesis and (iii) high efficiency of GAG synthesis leads to a severe phenotype, even if residual enzyme activity is detected. This correlation was found to be valid in 15 out of 17 patients tested. Conclusion: Analysis of efficiency of GAG synthesis and residual activity of the enzyme may be considered for prediction of severity of MPS patients' clinical phenotypes. [source] | |||||||||||||