959 resultados para Average Case Complexity
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A study of the potential role of aerosols in modifying clouds and precipitation is presented using a numerical atmospheric model. Measurements of cloud condensation nuclei (CCN) and cloud size distribution properties taken in the southwestern Amazon region during the transition from dry to wet seasons were used as guidelines to define the microphysical parameters for the simulations. Numerical simulations were carried out using the Brazilian Development on Regional Atmospheric Modeling System, and the results presented considerable sensitivity to changes in these parameters. High CCN concentrations, typical of polluted days, were found to result in increases or decreases in total precipitation, depending on the level of pollution used as a reference, showing a complexity that parallels the aerosol-precipitation interaction. Our results show that on the grids evaluated, higher CCN concentrations reduced low-to-moderate rainfall rates and increased high rainfall rates. The principal consequence of the increased pollution was a change from a warm to a cold rain process, which affected the maximum and overall mean accumulated precipitation. Under polluted conditions, cloud cover diminished, allowing greater amounts of solar radiation to reach the surface. Aerosol absorption of radiation in the lower layers of the atmosphere delayed convective evolution but produced higher maximum rainfall rates due to increased instability. In addition, the intensity of the surface sensible heat flux, as well as that of the latent heat flux, was reduced by the lower temperature difference between surface and air, producing greater energy stores at the surface.
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The Southwest region of the Bahia state in Brazil hosts the largest uranium reserve of the country (100 kton in uranium, only), plus the cities of Caetite, Lagoa Real and Igapora. In this work, aim was at the investigation of uranium burdens on residents of these cities by using teeth as bioindicators, as a contribution for possible radiation protection measures. Thus, a total of 41 human teeth were collected, plus 50 from an allegedly uranium free area (the control region). Concentrations of uranium in teeth from residents of 5- to 87-y old were determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). The highest uranium concentration in teeth was measured from samples belonging to residents of Caetite (median equal to 16 ppb). Assuming that the uranium concentrations in teeth and bones are similar within 10-20% (for children and young adults), it concluded that uranium body levels in residents of Caetite are at least one order of magnitude higher than the worldwide average. This finding led to conclude that daily ingestion of uranium, from food and water, is equally high.
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An operational complexity model (OCM) is proposed to enable the complexity of both the cognitive and the computational components of a process to be determined. From the complexity of formation of a set of traces via a specified route a measure of the probability of that route can be determined. By determining the complexities of alternative routes leading to the formation of the same set of traces, the odds ratio indicating the relative plausibility of the alternative routes can be found. An illustrative application to a BitTorrent piracy case is presented, and the results obtained suggest that the OCM is capable of providing a realistic estimate of the odds ratio for two competing hypotheses. It is also demonstrated that the OCM can be straightforwardly refined to encompass a variety of circumstances.
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The purpose of this study is to empirically analyze the main factors that determine the first-day return and the Flipping activity in Brazilian IPOs, taking into account expected results according to national and international researches. The data base encompasses IPOs that took place between May 2004 and February 2011, summing up to 129 IPOs and approximately R$ 128 billion offering. The first-day return, which means the “money left on the table”, was on average 4.6% taking into consideration the issue price, while the Flipping activity totalized R$ 7.2 billion, meaning 5.6% of the offering. The first-day return was analyzed before and after the first trade, and evidences were found supporting (a) the exogenous determination of the issue price, (b) the opening price dependence of prospectus disclosure and of other variables, observable previously to the bookbuilding process, and (c) the cascade behavior of investors in the pricing after the first trade, particularly driven by the underwriter behavior. In regards to the Flipping, it was notorious depending on how much the IPO succeeded, being concentrated in and homogeneous along the first-day, despite the intense negotiation in the first minute. As a general contribution to literature, it was concluded that Information Asymmetry Theory arguments are not sufficient to explain the first-day Underpricing and the Flipping, being necessary arguments based on Behavioral Finance adapted to an intraday perspective.
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Esta tese tem por objetivo examinar as características do processo de decisão em que credores optam pela recuperação judicial ou liquidação da empresa em dificuldade financeira. O trabalho está dividido em quatro capítulos. No segundo capítulo, apresenta-se, de forma sistematizada, referencial teórico e evidências empíricas para apontar resultados importantes sobre estudos desenvolvidos nas áreas de recuperação de empresas e falência. O capítulo também apresenta três estudos de caso com o propósito de mostrar a complexidade de cada caso no que diz respeito à concentração de recursos, conflito de interesse entre as classes de credores e a decisão final sobre a aprovação ou rejeição do plano de recuperação judicial. No terceiro capítulo, analisam-se os determinantes do atraso pertinente à votação do plano de recuperação judicial. O trabalho propõe um estudo empírico dos atrasos entre 2005 e 2014. Os resultados sugerem que: (i) maior concentração da dívida entre as classes de credores possui relação com atrasos menores; (ii) maior quantidade de bancos para votar o plano de recuperação judicial possui relação com maiores atrasos; (iii) o atraso médio na votação diminui quando apenas uma classe de credores participa da votação do plano; (iv) credores trabalhistas e com garantia real atrasam a votação quando o valor dos ativos para garantir a dívida em caso de liquidação é maior; (v) o atraso médio na votação é maior em casos de pior desempenho do setor de atuação do devedor, sendo solicitado pelas classes quirografária e com garantia real; e (vi) a proposta de venda de ativos é o principal tópico discutido nas reuniões de votação do plano nos casos em que o atraso na votação é maior. Por fim, no quarto capítulo, apresenta-se evidência sobre a votação dos credores e a probabilidade de aprovação do plano de recuperação judicial. Os resultados sugerem que: (i) credores trabalhistas estão propensos a aprovar o plano de recuperação mesmo quando o plano é rejeitado pelas demais classes; (ii) planos com propostas de pagamento mais heterogêneas para as três classes de credores possuem menor chance de serem aceitos; (iii) a chance de aprovação do plano diminui nos casos em que mais credores quirografários participam da recuperação; e (iv) planos com proposta de venda de ativos possuem maior chance de serem aprovados. Finalmente, maior concentração da dívida na classe com garantia real diminui a chance de aprovação do plano, e o contrário ocorre na classe quirografária.
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This thesis was written as part of a Double-Degree Masters program in Management, with focus in Marketing. Aligned with the nature of the degree, this study aims to be a useful tool for managers and marketers, which conduct business online. This thesis is a study of Content Marketing in the content of online commercial product pages. Its aim is to understand how to use content marketing to drive conversion, by understanding consumer attitudes and purchase intention towards content. A in-depth study of existing theories and exploratory primary research was developed in other to attain these objectives. Business-to-consumer electronic commerce (B2C e-commerce) has provided consumers and online retailers with a more effective medium to perform online transactions through commercial websites. Although consumers have realized that the benefits of online shopping; such as time saving, minimizing effort, convenience, broader selection, and wider access to information, they are still greatly unwilling to shop online. Consumers shop essentially for two motives, to meet experiential (fun) or goal-oriented (efficiency) needs (Wolfinbarger & Gilly, 2001). The information provided by content marketing seeks to focus on consumers need for information and entertainment, instead of focusing on the brand. Thus, it is expected that the type of content format will have different effects on the attitudes and purchase intention on the online shopper, depending on the online shopping purpose. Concretely, a goal-oriented shopper should find user generated content (UGC) to be more valuable content formats, since they decrease the amount of search effort. While on the other hand, videos & tutorials (VT) might be perceived as more valuable for a consumer looking to spend time and being entertained through online shopping. The exploratory research was characterized by a survey experiment with online consumers. Participants were exposed to stimuli of content marketing tested according to their attitudes and purchase intention. The focus was to understand the impact of two different content marketing tactics—User-generated content and Videos & Tutorials—on attitudes and purchase intentions and how they interact with content complexity. The results indicate that content marketing in commercial product pages is relevant in driving consumer attitudes and purchase intentions. Consumers are not motivated by a specific content marketing tactic, unless that content has a certain level of complexity. In that case, Ur-Generated Content becomes a relevant tactic in product pages, however VT is not.
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As globalization increases integration, a new playing field is emerging which is driving the need for operational efficiencies and alignment of complementary capabilities among countries to build sustainable models and integrated offerings. As demands increase, companies are turning to effective project management as means to control operations and countries are increasing the amount of mega projects to boost their competitiveness and global footprint. Given the scale, complexity, political nature, multicultural makeup, and high level of visibility; mega projects rely on successful stakeholder management to effectively manage its operational, tactical, and strategic levels to execute their mission. This paper examines the success drivers of mega projects and presents an in depth stakeholder assessment of the Panama Canal Expansion mega project to identify the perceived value to its stakeholder community. The stakeholder categories include: the Panama Canal Authority, subcontractors executing the expansion project, customers of the canal in Panama and U.S., as well as the communities surrounding the Panama Canal and ports in the U.S. East Coast. The conclusion of this paper captures the relationship between the effective stakeholder engagement from the Panama Canal Authority, the perceived value of the Panamanian stakeholders, and compares it to U.S. based mega projects being executed simultaneously to allow the U.S. East Coast ports to accommodate increased cargo volumes.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Lorryia formosa Cooreman has been collected on many different host plants around the world. The biological cycle of this species was studied at 28 degrees C with mites collected from a rubber tree crop. The life table was constructed based on sixty individuals. The average lifetime was 37.43 +/- 20.23 (SE) days, and the r(m) was 0.08. The sex ratio was totally female biased, and unfertilized eggs developed into females. This is the first record of thelytoky in Tydeoidea proved by rearing.
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The objective of this study was to evaluate the effect of fertilization with zinc or boron on the growth and dry matter production, nutritional value and accumulation of nutrients in white oats. The study comprised two experiments conducted in glasshouses, the first consisting of the application of four doses of zinc (0, 0.2, 0.4 and 0.6 mg/dm³) in the form of zinc sulphate (20% Zn), and the second consisting of the application of four doses of boron (0, 0.2, 0.4 and 0.6 mg/dm³) in the form of Borax (11% B). The experimental design in each case was a randomized block design, with five replicates. Fertilization with zinc and boron increased the growth of white oats, but had no significant effect on the nutritional value of the forage. Higher levels of absorption and accumulation of nutrients in plant tissues were observed following the application of boron and zinc at rates of up to 0.60 mg/dm³ of soil.
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Experimental data on the precipitation chemistry in the semi-arid savanna of South Africa is presented in this paper. A total of 901 rainwater samples were collected with automatic wet-only samplers at a rural site, Louis Trichardt, and at an industrial site, Amersfoort, from July 1986 to June 1999. The chemical composition of precipitation was analysed for seven inorganic and two organic ions, using ion chromatography. The most abundant ion was SO(4)(2-) and a large proportion of the precipitation is acidic, with 98% of samples at Amersfoort and 94% at Louis Trichardt having a pH below 5.6 ( average pH of 4.4 and 4.9, respectively). This acidity results from a mixture of mineral and organic acids, with mineral acids being the primary contributors to the precipitation acidity in Amersfoort, while at Louis Trichardt, organic and mineral acids contribute equal amounts of acidity. It was found that the composition of rainwater is controlled by five sources: marine, terrigenous, nitrogenous, biomass burning and anthropogenic sources. The relative contributions of these sources at the two sites were calculated. Anthropogenic sources dominate at Amersfoort and biomass burning at Louis Trichardt. Most ions exhibit a seasonal pattern at Louis Trichardt, with the highest concentrations occurring during the austral spring as a result of agricultural activities and biomass combustion, while at Amersfoort it is less pronounced due to the dominance of relatively constant industrial emissions. The results are compared to observations from other African regions.
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The Southwest region of the Bahia state in Brazil hosts the largest uranium reserve of the country (100 kton in uranium, only), plus the cities of Caetite, Lagoa Real and Igapora. In this work, aim was at the investigation of uranium burdens on residents of these cities by using teeth as bioindicators, as a contribution for possible radiation protection measures. Thus, a total of 41 human teeth were collected, plus 50 from an allegedly uranium free area (the control region). Concentrations of uranium in teeth from residents of 5- to 87-y old were determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). The highest uranium concentration in teeth was measured from samples belonging to residents of Caetite (median equal to 16 ppb). Assuming that the uranium concentrations in teeth and bones are similar within 10-20% (for children and young adults), it concluded that uranium body levels in residents of Caetite are at least one order of magnitude higher than the worldwide average. This finding led to conclude that daily ingestion of uranium, from food and water, is equally high.
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The performance of 36 models (22 ocean color models and 14 biogeochemical ocean circulation models (BOGCMs)) that estimate depth-integrated marine net primary productivity (NPP) was assessed by comparing their output to in situ (14)C data at the Bermuda Atlantic Time series Study (BATS) and the Hawaii Ocean Time series (HOT) over nearly two decades. Specifically, skill was assessed based on the models' ability to estimate the observed mean, variability, and trends of NPP. At both sites, more than 90% of the models underestimated mean NPP, with the average bias of the BOGCMs being nearly twice that of the ocean color models. However, the difference in overall skill between the best BOGCM and the best ocean color model at each site was not significant. Between 1989 and 2007, in situ NPP at BATS and HOT increased by an average of nearly 2% per year and was positively correlated to the North Pacific Gyre Oscillation index. The majority of ocean color models produced in situ NPP trends that were closer to the observed trends when chlorophyll-alpha was derived from high-performance liquid chromatography (HPLC), rather than fluorometric or SeaWiFS data. However, this was a function of time such that average trend magnitude was more accurately estimated over longer time periods. Among BOGCMs, only two individual models successfully produced an increasing NPP trend (one model at each site). We caution against the use of models to assess multiannual changes in NPP over short time periods. Ocean color model estimates of NPP trends could improve if more high quality HPLC chlorophyll-alpha time series were available.