928 resultados para Top 10


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The aim of this study was to examine the effect of positioning on the correctness of decision making of top-class referees and assistant referees during international games. Match analyses were carried out during the Fe´de´ration Internationale de Football Association (FIFA) Confederations Cup 2009 and 380 foul play incidents and 165 offside situations were examined. The error percentage for the referees when indicating the incidents averaged 14%. The lowest error percentage occurred in the central area of the field, where the collaboration of the assistant referee is limited, and was achieved when indicating the incidents from a distance of 11–15 m, whereas this percentage peaked (23%) in the last 15-min match period. The error rate for the assistant referees was 13%. Distance of the assistant referee to the offside line did not have an impact on the quality of the offside decision. The risk of making incorrect decisions was reduced when the assistant referees viewed the offside situations from an angle between 46 and 608. Incorrect offside decisions occurred twice as often in the second as in the first half of the games. Perceptual-cognitive training sessions specific to the requirements of the game should be implemented in the weekly schedule of football officials to reduce the overall error rate.

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In this paper, multiple regression analysis is used to model the top of descent (TOD) location of user-preferred descent trajectories computed by the flight management system (FMS) on over 1000 commercial flights into Melbourne, Australia. In addition to recording TOD, the cruise altitude, final altitude, cruise Mach, descent speed, wind, and engine type were also identified for use as the independent variables in the regression analysis. Both first-order and second-order models are considered, where cross-validation, hypothesis testing, and additional analysis are used to compare models. This identifies the models that should give the smallest errors if used to predict TOD location for new data in the future. A model that is linear in TOD altitude, final altitude, descent speed, and wind gives an estimated standard deviation of 3.9 nmi for TOD location given the trajectory parame- ters, which means about 80% of predictions would have error less than 5 nmi in absolute value. This accuracy is better than demonstrated by other ground automation predictions using kinetic models. Furthermore, this approach would enable online learning of the model. Additional data or further knowledge of algorithms is necessary to conclude definitively that no second-order terms are appropriate. Possible applications of the linear model are described, including enabling arriving aircraft to fly optimized descents computed by the FMS even in congested airspace.

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YBaCuO and GdBaCuO + 15 wt% Ag large, single-grain, bulk superconductors have been fabricated via the top-seeded, melt-growth (TSMG) process using a generic NdBCO seed. The mechanical behavior of both materials has been investigated by means of three-point bending (TPB) and transversal tensile tests at 77 and 300 K. The strength, fracture toughness and hardness of the samples were studied for two directions of applied load to obtain comprehensive information about the effect of microstructural anisotropy on the macroscopic and microscopic mechanical properties of these technologically important materials. Splitting (Brazilian) tests were carried out on as-melt-processed cylindrical samples following a standard oxygenation process and with the load applied parallel to the growth-facet lines characteristic of the TSMG process. In addition, the elastic modulus of each material was measured by three different techniques and related to the microstructure of each sample using optical microscopy. The results show that both the mechanical properties and the elastic modulus of both YBCO and GdBCP/Ag are improved at 77 K. However, the GdBCO/Ag samples are less anisotropic and exhibit better mechanical behavior due to the presence of silver particles in the bulk, superconducting matrix. The splitting tensile strength was determined at 77 K and both materials were found to exhibit similar behavior, independently of their differences in microstructure.

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We propose the use of a polarization based interferometer with variable transfer function for the generation of temporally flat top pulses from gain switched single mode semiconductor lasers. The main advantage of the presented technique is its flexibility in terms of input pulse characteristics, as pulse duration, spectral bandwidth and operating wavelength. Theoretical predictions and experimental demonstrations are presented and the proposed technique is applied to two different semiconductor laser sources emitting in the 1550 nm region. Flat top pulses are successfully obtained with input seed pulses with duration ranging from 40 ps to 100 ps.

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One of the fundamental tenets of oncology is that tumors arise from stem cells. In the colon, stem cells are thought to reside at the base of crypts. In the early stages of tumorigenesis, however, dysplastic cells are routinely found at the luminal surface of the crypts whereas the cells at the bases of these same crypts appear morphologically normal. To understand this discrepancy, we evaluated the molecular characteristics of cells isolated from the bases and orifices of the same crypts in small colorectal adenomas. We found that the dysplastic cells at the tops of the crypts often exhibited genetic alterations of adenomatous polyposis coli (APC) and neoplasia-associated patterns of gene expression. In contrast, cells located at the base of these same crypts did not contain such alterations and were not clonally related to the contiguous transformed cells above them. These results imply that development of adenomatous polyps proceeds through a top-down mechanism. Genetically altered cells in the superficial portions of the mucosae spread laterally and downward to form new crypts that first connect to preexisting normal crypts and eventually replace them.

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The hierarchical properties of potential energy landscapes have been used to gain insight into thermodynamic and kinetic properties of protein ensembles. It also may be possible to use them to direct computational searches for thermodynamically stable macroscopic states, i.e., computational protein folding. To this end, we have developed a top-down search procedure in which conformation space is recursively dissected according to the intrinsic hierarchical structure of a landscape's effective-energy barriers. This procedure generates an inverted tree similar to the disconnectivity graphs generated by local minima-clustering methods, but it fundamentally differs in the manner in which the portion of the tree that is to be computationally explored is selected. A key ingredient is a branch-selection algorithm that takes advantage of statistically predictive properties of the landscape to guide searches down the tree branches that are most likely to lead to the physically relevant macroscopic states. Using the computational folding of a β-hairpin-forming peptide as an example, we show that such predictive properties indeed exist and can be used for structure prediction by free-energy global minimization.

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Introdução: Crianças com transtorno fonológico (TF) apresentam dificuldade na percepção de fala, em processar estímulos acústicos quando apresentados de forma rápida e em sequência. A percepção dos sons complexos da fala, dependem da integridade no processo de codificação analisado pelo Sistema Nervoso Auditivo. Por meio do Potencial Evocado Auditivo de Tronco Encefálico com estímulo complexo (PEATEc) é possível investigar a representação neural dos sons em níveis corticais e obter informações diretas sobre como a estrutura do som da sílaba falada é codificada no sistema auditivo. Porém, acredita-se que esse potencial sofre interferências tanto de processos bottom-up quanto top-down, o que não se sabe é quanto e como cada um desses processos modifica as respostas do PEATEc. Uma das formas de investigar a real influência dos aspectos top-down e bottom-up nos resultados do PEATEc é estimulando separadamente esses dois processos por meio do treinamento auditivo e da terapia fonoaudiológica. Objetivo: Verificar o impacto da estimulação sensorial (processamento bottom-up) e cognitiva (processamento top-down), separadamente, nos diferentes domínios da resposta eletrofisiológica do PEATEc. Método: Participaram deste estudo 11 crianças diagnosticadas com TF, com idades entre 7 e 10:11, submetidas a avaliação comportamental e eletrofisiológica e então dividas nos grupos Bottom-up (B-U) (N=6) e Top-down T-D (N=5). A estimulação bottom-up foi voltada ao treinamento das habilidades sensoriais, através de softwares de computador. A estimulação top-down foi realizada por meio de tarefas para estimular as habilidades cognitiva por meio do Programa de Estimulação Fonoaudiológica (PEF). Ambas as estimulações foram aplicadas uma vez por semana, num período de aproximadamente 45 minutos por 12 semanas. Resultados: O grupo B-U apresentou melhoras em relação aos domínios onset e harmônicos e no valor da pontuação do escore após ser submetido à estimulação bottom-up. Por sua vez, após serem submetidos à estimulação top-down, o grupo T-D apresentou melhoras em relação aos domínios onset, espectro-temporal, fronteiras do envelope e harmônicos e para os valores da pontuação do escore. Conclusão: Diante dos resultados obtidos neste estudo, foi possível observar que a estimulação sensorial (processamento bottom-up) e a estimulação cognitiva (processamento top-down) mostraram impactar de forma diferente a resposta eletrofisiológica do PEATEc

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The SME access-to-finance problem is not universal in the European Union and there are reasons for the fall in credit aggregates and higher SME lending rates in southern Europe. Possible market failures, high unemployment and externalities justify making greater and easier access to finance for SMEs a top priority. Previous European initiatives were able to support only a tiny fraction of Europe’s SMEs; merely stepping-up these programmes is unlikely to result in a breakthrough. Without repairing bank balance sheets and resuming economic growth, initiatives to help SMEs get access to finance will have limited success. The European Central Bank can foster bank recapitalisation by performing in the toughest possible way the asset quality review before it takes over the single supervisory role. Of the possible initiatives for fostering SME access to finance, a properly designed scheme for targeted central bank lending seems to be the best complement to the banking clean-up, but other options, such as increased European Investment Bank lending and the promotion of securitisation of SME loans, should also be explored.

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The Asian economy is expected to realise favourable growth during the first half of this century, but there is no guarantee. There is a discussion about a ‘middle-income trap’, which refers to a country that has realised rapid growth to become a middle-income country but is unable to grow further. A middle-income trap could occur not only if there is a delay in shifting the economy toward a productivity-driven structure, but also if there is a worsening of income distribution.We consider this in line with the theories of development economics and through a quantitative analysis. The relationship between income inequality and the trap can be explained by the Kuznets hypothesis and the basic-needs approach. Our quantitative analysis supports the Kuznets hypothesis, and indicates that,although a low-income country can accelerate its economic growth with the worsening of income distribution as an engine, a middle income country would experience a decreasing growth rate if it fails to narrow the income gap between the top and bottom income groups. The results also show that the basic-needs approach is also applicable in practice, and imply that the improvement of access to secondary education is important. A sensitivity analysis for three Asian upper-middle-income countries(China, Malaysia and Thailand) also shows that the situation related to a middle-income trap is worse than average in China and Malaysia. These two countries, according to the result of the sensitivity analysis, should urgently improve access to secondary education and should implement income redistribution measures to develop high-tech industries, before their demographic dividends expire. Income redistribution includes the narrowing of rural urban income disparities, benefits to low-income individuals, direct income transfers, vouchers or free provision of education and health-care, and so on, but none of these are simple to implement.

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Since taking power in 2009, the Alliance for European Integration (AIE) has been trying to end Moldova’s dependence on Russian gas. Currently, natural gas accounts for about 50% of the country’s energy balance (excluding Transnistria), and Gazprom has a monopoly on the supply of gas to the republic. The key element of Chișinău’s diversification project is the construction of the Iasi-Ungheni pipeline, which is designed to link the Moldovan and Romanian gas transmission networks, and consequently make it possible for Moldova to purchase gas from countries other than Russia. Despite significant delays, construction work on the interconnector began in August 2013. The Moldovan government sees ensuring energy independence from Russia as its top priority. The significance and urgency of the project reflect Chișinău’s frustration at Moscow’s continued attempts to use its monopoly of Moldova’s energy sector to exert political pressure on the republic. Nonetheless, despite numerous declarations by Moldovan and Romanian politicians, the Iasi- -Ungheni pipeline will not end Moldova’s dependence on Russian gas before the end of the current decade. This timeframe is unrealistic for two reasons: first, because an additional gas pipeline from Ungheni to Chisinau and a compression station must be constructed, which will take at least five years and will require significant investment; and second, because of the unrelenting opposition to the project coming from Gazprom, which currently controls Moldova’s pipelines and will likely try to torpedo any energy diversification attempts. Independence from Russian gas will only be possible after the the Gazprom-controlled Moldova-GAZ, the operator of the Moldovan transmission network and the country’s importer of natural gas, is divided. The division of the company has in fact been envisaged in the EU’s Third Energy Package, which is meant to be implemented by Moldova in 2020.

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To date, the negotiations over chemicals in the Translatlantic Trade and Investment Partnership (TTIP) have not shown sufficient ambition. The talks have focused too much on the differences in the two ‘systems’, rather than on the actual levels of health and environmental protection for substances regulated by both the US and the EU. Given the accomplishments within the OECD and the UN Globally Harmonised System of Classification and Labelling of Chemicals (GHS), the question is whether TTIP can be any more ambitious in the area of chemicals? We find that there is no detailed or systematic knowledge about how the two levels of protection in chemicals compare, although caricatures and stereotypes abound. This is partly due to an obsessive focus on a single US federal law, the Toxic Subtances Control Act (TSCA), whereas in practice US protection depends on many statutes and regulations, as well as on voluntary withdrawals (under pressure from the Environmental Protection Agency) and severe common law liability. This paper makes the economic case for firmly addressing the regulatory barriers, discusses the EU’s proposals, finds that the European Parliament’s Resolution on TTIP of July 2015 lacks a rationale (for chemicals), argues that both TSCA and REACH ought to be improved (based on ‘better regulation’), discusses the link with a global regime, advocates significant improvement of market access where equivalence of health and environmental objectives is agreed and, finally, proposes to lower the costs for companies selling in both markets by allowing them to opt into the other party’s more stringent rules, thereby avoiding duplication while racing-to-the-top. The ‘living agreement’ on chemicals ought to be led by a new TTIP institution authorised to establish the level of health and environmental protection on both sides of the Atlantic for substances regulated on both sides. These findings will lay the foundation for a highly beneficial lowering of trading costs without in any way affecting the level of protection. Indeed, this is exactly what TTIP is, or should be, all about.This paper is the 10th in a series produced in the context of the “TTIP in the Balance” project, jointly organised by CEPS and the Center for Transatlantic Relations (CTR) in Washington, D.C. It is published simultaneously on the CEPS (www.ceps.eu) and CTR websites (http://transatlantic.sais-jhu.edu).