748 resultados para Hybrid regime
Resumo:
Em São Paulo, destaca-se a viticultura como atividade familiar de caráter artesanal. Nas bacias de maior concentração atual da vitivinicultura, ocorre um período chuvoso que se estende de novembro a fevereiro, que alcança grande parte das variedades da região em fase de crescimento e maturação da baga, o que afeta negativamente a qualidade da uva e do vinho artesanal, na maioria das safras. Por outro lado, nas mesmas regiões, ocorre um período mais favorável, que é o outono/inverno com potencial de soma térmica adequado ao crescimento da videira e com incidência de um longo período de baixa pluviometria, entre os meses de abril e outubro. Um experimento foi conduzido em Jundiaí (SP), região de média altitude (700 m), com variedades de uvas híbridas e fina, no qual, objetivou-se estudar os impactos ecofisiológicos do cultivo da videira conduzida sob dupla poda, forçando-se a condução das plantas por quatro estações de cultivo sequenciais de verão e inverno; analisaram-se aspectos da ecofiosologia da cultura e a composição quali-quantitativa do rendimento. Os resultados mostram que a estação de outono-inverno apresenta condições mais favoráveis à maturação fenólica das bagas, com chuvas mais bem distribuídas e desconcentradas no período do estabelecimento do fruto à colheita. A uva colhida na estação de outono-inverno apresentou maiores índices de pigmentação fenólica em relação à estação de cultivo tradicional, sendo que o controle do nível de reservas da planta revelou influência da dupla poda sequencial sobre esta variável, o que inspira práticas de manejo específicas para este tipo de exploração da videira.
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This symposium presents research from different contexts to improve our collective understanding of a variety of aspects of mixed forms of service delivery, be they mixed contracting at the level of the market (which is more common in the U.S.), or mixed management and ownership at the level of the firm (which is more common in Europe). The articles included in this special symposium examine the factors that give rise to mixed forms of service delivery (e.g., economic and fiscal stress, regulatory flexibility, geography, management) and how these factors impact their design and operation. Articles also explore the performance of mixed forms of service delivery relative to more conventional arrangements like contracted or direct service delivery. The articles contribute to a better theoretical and conceptual understanding of mixed/hybrid forms of services delivery.
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We investigate nuclear magnetic resonance (NMR) parameters of the rhodopsin chromophore in the dark state of the protein and in the early photointermediate bathorhodopsin via first-principles molecular dynamics simulations and NMR chemical shift calculations in a hybrid quantum/classical (QM/MM) framework. NMR parameters are particularly sensitive to structural properties and to the chemical environment, which allows us to address different questions about the retinal chromophore in situ. Our calculations show that both the 13C and the 1H NMR chemical shifts are rather insensitive to the protonation state of Glu181, an ionizable amino acid side chain located in the vicinity of the isomerizing 11-cis bond. Thus, other techniques should be better suited to establish its protonation state. The calculated chemical shifts for bathorhodopsin further support our previously published theoretical structure, which is in very good agreement with more recent X-ray data.
Resumo:
Regulation has in many cases been delegated to independent agencies, which has led to the question of how democratic accountability of these agencies is ensured. There are few empirical approaches to agency accountability. We offer such an approach, resting upon three propositions. First, we scrutinize agency accountability both de jure (accountability is ensured by formal rights of accountability 'fora' to receive information and impose consequences) and de facto (the capability of fora to use these rights depends on resources and decision costs that affect the credibility of their sanctioning capacity). Second, accountability must be evaluated separately at political, operational and managerial levels. And third, at each level accountability is enacted by a system of several (partially) interdependent fora, forming together an accountability regime. The proposed framework is applied to the case of the German Bundesnetzagentur's accountability regime, which shows its suitability for empirical purposes. Regulatory agencies are often considered as independent, yet accountable. This article provides a realistic framework for the study of accountability 'regimes' in which they are embedded. It emphasizes the need to identify the various actors (accountability fora) to which agencies are formally accountable (parliamentary committees, auditing bodies, courts, and so on) and to consider possible relationships between them. It argues that formal accountability 'on paper', as defined in official documents, does not fully account for de facto accountability, which depends on the resources possessed by the fora (mainly information-processing and decision-making capacities) and the credibility of their sanctioning capacities. The article applies this framework to the German Bundesnetzagentur.
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The CO2-laser-MAG hybrid welding process has been shown to be a productive choice for the welding industry, being used in e.g. the shipbuilding, pipe and beam manufacturing, and automotive industries. It provides an opportunity to increase the productivity of welding of joints containing air gaps compared with autogenous laser beam welding, with associated reductions in distortion and marked increases in welding speeds and penetration in comparison with both arc and autogenous laser welding. The literature study indicated that the phenomena of laser hybrid welding are mostly being studied using bead-on-plate welding or zero air gap configurations. This study shows it very clearly that the CO2 laser-MAG hybrid welding process is completely different, when there is a groove with an air gap. As in case of industrial use it is excepted that welding is performed for non-zero grooves, this study is of great importance for industrial applications. The results of this study indicate that by using a 6 kW CO2 laser-MAG hybrid welding process, the welding speed may also be increased if an air gap is present in the joint. Experimental trials indicated that the welding speed may be increased by 30-82% when compared with bead-on-plate welding, or welding of a joint with no air gap i.e. a joint prepared as optimum for autogenous laser welding. This study demonstrates very clearly, that the separation of the different processes, as well as the relative configurations of the processes (arc leading or trailing) affect welding performance significantly. These matters influence the droplet size and therefore the metal transfer mode, which in turn determined the resulting weld quality and the ability to bridge air gaps. Welding in bead-onplate mode, or of an I butt joint containing no air gap joint is facilitated by using a leading torch. This is due to the preheating effect of the arc, which increases the absorptivity of the work piece to the laser beam, enabling greater penetration and the use of higher welding speeds. With an air gap present, air gap bridging is more effectively achieved by using a trailing torch because of the lower arc power needed, the wider arc, and the movement of droplets predominantly towards the joint edges. The experiments showed, that the mode of metal transfer has a marked effect on gap bridgeability. Transfer of a single droplet per arc pulse may not be desirable if an air gap is present, because most of the droplets are directed towards the middle of the joint where no base material is present. In such cases, undercut is observed. Pulsed globular and rotational metal transfer modes enable molten metal to also be transferred to the joint edges, and are therefore superior metal transfer modes when bridging air gaps. It was also found very obvious, that process separation is an important factor in gap bridgeability. If process separation is too large, the resulting weld often exhibits sagging, or no weld may be formed at all as a result of the reduced interaction between the component processes. In contrast, if the processes are too close to one another, the processing region contains excess molten metal that may create difficulties for the keyhole to remain open. When the distance is optimised - i.e. a separation of 0-4 mm in this study, depending on the welding speed and beam-arc configuration - the processes act together, creating beneficial synergistic effects. The optimum process separation when using a trailing torch was found to be shorter (0-2 mm) than when a leading torch is used (2-4 mm); a result of the facilitation of weld pool motion when the latter configuration is adopted. This study demonstrates, that the MAG process used has a strong effect on the CO2-laser-MAG hybrid welding process. The laser beam welding component is relatively stable and easy to manage, with only two principal processing parameters (power and welding speed) needing to be adjusted. In contrast, the MAG process has a large number of processing parameters to optimise, all of which play an important role in the interaction between the laser beam and the arc. The parameters used for traditional MAG welding are often not optimal in achieving the most appropriate mode of metal transfer, and weld quality in laser hybrid welding, and must be optimised if the full range of benefits provided by hybrid welding are to be realised.
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A hybrid electric vehicle is a fast-growing concept in the field of vehicle industry. Nowadays two global problems make manufactures to develop such systems. These problems are: the growing cost of a fuel and environmental pollution. Also development of controlled electric drive with high control accuracy and reliability allows improving of vehicle drive characteristics. The objective of this Diploma Thesis is to investigate the possibilities of electrical drive application for new principle of parallel hybrid vehicle system. Electric motor calculations, selection of most suitable control system and other calculations are needed. This work is not final work for such topic. Further investigation with more precise calculations, modeling, measurements and cost calculations are needed to answer the question if such system is efficient.
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The aim of this work is to design a flywheel generator for a diesel hybrid working machine. In this work we perform detailed design of a generator. Mobile machines are commonly used in industry: road building machines, three harvesting machines, boring machines, trucks and other equipment. These machines work with a hydraulic drive system. This system provides good service property and high technical level. Manufacturers of mobile machines tend to satisfy all requirements of customers and modernized drive system. In this work also a description of the frequency inverter is present. Power electronics system is one of the basic parts for structures perform in the project.
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Este artículo describe investigación sobre los efectos de la desambiguación morfosintáctica usada como un preproceso de un analizador sint´actico profundo basado en HPSG, en el contexto del desarrollo de un treebank del español de código abierto, en el entorno de DELPH-IN. La anotación treebank se realiza manualmente tomando las decisiones apropiadas entre las opciones propuestas por el sistema y ordenadas por un módulo estadístico. Los experimentos presentados muestran que el uso de un etiquetador reduce la ambigüedad de las frases, y contribuye a limitar la cantidad de frases cuyo análisis sobrepasa a el límite de tiempo, y ayuda a al m´odulo estadístico a clasificar el árbol correcto entre los n mejores. Por un lado, nuestros resultados validan los beneficios ya reportados en la literatura de tal preproceso de análisis profundo con respecto a la velocidad, cobertura y precisión. Por otro lado, proponemos una estrategia basada en existentes herramientas de código abierto y recursos para desarrollar con alta consitencia treebanks de sintaxis profunda para idiomas con limitada disponibilidad de recursos lingüísticos.
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AimGlobal environmental changes challenge traditional conservation approaches based on the selection of static protected areas due to their limited ability to deal with the dynamic nature of driving forces relevant to biodiversity. The Natura 2000 network (N2000) constitutes a major milestone in biodiversity conservation in Europe, but the degree to which this static network will be able to reach its long-term conservation objectives raises concern. We assessed the changes in the effectiveness of N2000 in a Mediterranean ecosystem between 2000 and 2050 under different combinations of climate and land cover change scenarios. LocationCatalonia, Spain. MethodsPotential distribution changes of several terrestrial bird species of conservation interest included in the European Union's Birds Directive were predicted within an ensemble-forecasting framework that hierarchically integrated climate change and land cover change scenarios. Land cover changes were simulated using a spatially explicit fire-succession model that integrates fire management strategies and vegetation encroachment after the abandonment of cultivated areas as the main drivers of landscape dynamics in Mediterranean ecosystems. ResultsOur results suggest that the amount of suitable habitats for the target species will strongly decrease both inside and outside N2000. However, the effectiveness of N2000 is expected to increase in the next decades because the amount of suitable habitats is predicted to decrease less inside than outside this network. Main conclusionsSuch predictions shed light on the key role that the current N2000may play in the near future and emphasize the need for an integrative conservation perspective wherein agricultural, forest and fire management policies should be considered to effectively preserve key habitats for threatened birds in fire-prone, highly dynamic Mediterranean ecosystems. Results also show the importance of considering landscape dynamics and the synergies between different driving forces when assessing the long-term effectiveness of protected areas for biodiversity conservation.
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Differences in parasite transmission intensity influence the process of acquisition of host immunity to Plasmodium falciparum malaria and ultimately, the rate of malaria related morbidity and mortality. Potential vaccines being designed to complement current intervention efforts therefore need to be evaluated against different malaria endemicity backgrounds. The associations between antibody responses to the chimeric merozoite surface protein 1 block 2 hybrid (MSP1 hybrid), glutamate-rich protein region 2 (GLURP R2) and the peptide AS202.11, and the risk of malaria were assessed in children living in malaria hyperendemic (Burkina Faso, n = 354) and hypo-endemic (Ghana, n = 209) areas. Using the same reagent lots and standardized protocols for both study sites, immunoglobulin (Ig) M, IgG and IgG sub-class levels to each antigen were measured by ELISA in plasma from the children (aged 6-72 months). Associations between antibody levels and risk of malaria were assessed using Cox regression models adjusting for covariates. There was a significant association between GLURP R2 IgG3 and reduced risk of malaria after adjusting age of children in both the Burkinabe (hazard ratio 0.82; 95 % CI 0.74-0.91, p < 0.0001) and the Ghanaian (HR 0.48; 95 % CI 0.25-0.91, p = 0.02) cohorts. MSP1 hybrid IgM was associated (HR 0.85; 95 % CI 0.73-0.98, p = 0.02) with reduced risk of malaria in Burkina Faso cohort while IgG against AS202.11 in the Ghanaian children was associated with increased risk of malaria (HR 1.29; 95 % CI 1.01-1.65, p = 0.04). These findings support further development of GLURP R2 and MSP1 block 2 hybrid, perhaps as a fusion vaccine antigen targeting malaria blood stage that can be deployed in areas of varying transmission intensity.
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AbstractPenetrating atherosclerotic aortic ulcer is a rare entity with poor prognosis in the setting of acute aortic syndrome. In the literature, cases like the present one, located in the aortic arch, starting with chest pain and evolving with dysphonia, are even rarer. The present report emphasizes the role played by computed tomography in the diagnosis of penetrating atherosclerotic ulcer as well as in the differentiation of this condition from other acute aortic syndromes. Additionally, the authors describe a new therapeutic approach represented by a hybrid endovascular surgical procedure for treatment of the disease.
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This work reviews recent studies of underpotential deposition (UPD) of several metals on Pt and Au substrates performed in the Grupo de Materiais Eletroquímicos e Métodos Eletroanalíticos (IQSC -- USP, São Carlos). The UPD Cu, Cd and Pb on Pt were analysed in terms of their influence in the oxygen evolution reaction. Partial blockage of surface active sites, promoted by Pb ad-atoms, resulted in a change from water to hydrogen peroxide as the final product. The Ag UPD on Pt and Au substrates was also discussed in this work. A detailed model of charge calculation for Ag monolayer was developed and confirmed by the rotating ring-disk data. The partial charge transfer in UPD studies was analysed in the Cd/Pt and Cd/Au systems and a value of 0.5 was found for the adsorption electrovalence of Cd ad-ions. The Sn/Pt UPD systems were studied from the point of view of the valences of metallic ions in solution. The deposition from Sn(IV) generates a full monolayer with a maximum occupation of approximately 40% of the surface active sites (340 µC cm-2) plus 105 µC cm-2 of Hads (half monolayer). Changing the metallic ion for Sn(II), it was possible to deposit a full monolayer (210 µC cm-2) without any detectable Hads. Finally, the effect of anions was discussed in the Zn/Pt and Zn/Au systems. Here, the hydrogen evolution reaction (her) and the hydrogen adsorption/desorption were used in order to investigate the maximum coverage of the surface with Zn ad-atoms. The full monolayer, characterised by the complete absence of Hads, was achieved only in 0.5 M HF solutions.
Resumo:
Objective. Recently, significant advances have been made in the early diagnosis of Alzheimer’s disease from EEG. However, choosing suitable measures is a challenging task. Among other measures, frequency Relative Power and loss of complexity have been used with promising results. In the present study we investigate the early diagnosis of AD using synchrony measures and frequency Relative Power on EEG signals, examining the changes found in different frequency ranges. Approach. We first explore the use of a single feature for computing the classification rate, looking for the best frequency range. Then, we present a multiple feature classification system that outperforms all previous results using a feature selection strategy. These two approaches are tested in two different databases, one containing MCI and healthy subjects (patients age: 71.9 ± 10.2, healthy subjects age: 71.7 ± 8.3), and the other containing Mild AD and healthy subjects (patients age: 77.6 ± 10.0; healthy subjects age: 69.4± 11.5). Main Results. Using a single feature to compute classification rates we achieve a performance of 78.33% for the MCI data set and of 97.56 % for Mild AD. Results are clearly improved using the multiple feature classification, where a classification rate of 95% is found for the MCI data set using 11 features, and 100% for the Mild AD data set using 4 features. Significance. The new features selection method described in this work may be a reliable tool that could help to design a realistic system that does not require prior knowledge of a patient's status. With that aim, we explore the standardization of features for MCI and Mild AD data sets with promising results.