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Hadoop performance modeling and job optimization for big data analyticsKhan, Mukhtaj January 2015 (has links)
Big data has received a momentum from both academia and industry. The MapReduce model has emerged into a major computing model in support of big data analytics. Hadoop, which is an open source implementation of the MapReduce model, has been widely taken up by the community. Cloud service providers such as Amazon EC2 cloud have now supported Hadoop user applications. However, a key challenge is that the cloud service providers do not a have resource provisioning mechanism to satisfy user jobs with deadline requirements. Currently, it is solely the user responsibility to estimate the require amount of resources for their job running in a public cloud. This thesis presents a Hadoop performance model that accurately estimates the execution duration of a job and further provisions the required amount of resources for a job to be completed within a deadline. The proposed model employs Locally Weighted Linear Regression (LWLR) model to estimate execution time of a job and Lagrange Multiplier technique for resource provisioning to satisfy user job with a given deadline. The performance of the propose model is extensively evaluated in both in-house Hadoop cluster and Amazon EC2 Cloud. Experimental results show that the proposed model is highly accurate in job execution estimation and jobs are completed within the required deadlines following on the resource provisioning scheme of the proposed model. In addition, the Hadoop framework has over 190 configuration parameters and some of them have significant effects on the performance of a Hadoop job. Manually setting the optimum values for these parameters is a challenging task and also a time consuming process. This thesis presents optimization works that enhances the performance of Hadoop by automatically tuning its parameter values. It employs Gene Expression Programming (GEP) technique to build an objective function that represents the performance of a job and the correlation among the configuration parameters. For the purpose of optimization, Particle Swarm Optimization (PSO) is employed to find automatically an optimal or a near optimal configuration settings. The performance of the proposed work is intensively evaluated on a Hadoop cluster and the experimental results show that the proposed work enhances the performance of Hadoop significantly compared with the default settings.
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Clean water from clean energy : removal of dissolved contaminants from brackish groundwater using wind energy powered electrodialysisMalek, Payam January 2015 (has links)
Around 770 million people lack access to improved drinking water sources (WHO 2013), urgently necessitating implementation of contaminant removal by e.g. desalination systems on a large scale. To improve water quality and enable use of brackish water sources for human consumption in remote arid areas, a directly coupled wind – electrodialysis system (Wind-ED) was developed. Modularity, sustainability and above all suitability for the practical use in off-grid locations were the main motivations and design objectives. The direct coupling of wind energy with membranes reduces the system costs as well as technical drawbacks associated with using intermediate energy storage systems. During this research, systematic experiments were performed using the Wind-ED system in order to determine desalination performance and clean water production, specific energy consumption (SEC) and current efficiency (ηc) under relevant conditions, such as varying: i) wind speed, ii) wind turbulence intensity, iii) oscillation periods, iv) varying NaCl concentrations and v) flow rates. Moreover, the competitive removal of four commonly available inorganic contaminants in brackish groundwater sources, nitrate (NO3-), fluoride (F-), sulphate (SO42-) and chloride (Cl-), were investigated. Firstly, to establish a systematic understanding of how and to what extent energy fluctuations influence the transport of the salt (i.e. NaCl) ions across the membranes, experiments were conducted using pulsed electric field assisted electrodialysis (pulsed-ED) over a wide range of frequencies (0.001 – 10 Hz) and duty cycles (20 – 80). The results showed that pulsation applied in the sub-limiting regime resulted in reduced water production, explained by the delays caused by the off-periods during the pulsed desalination process. At higher current densities, pulsation led to considerable improvements in current (e.g. up to 95%, for a feed solution of 500 mg/L and a pulse regime of 1 Hz at 50 V peak voltage) and significant reduction in water dissociation, explained by a reduction of concentration polarisation. Importantly, the pulsation had no significant effect on energy consumption or current efficiency suggesting that ED could be suitable for direct coupling to fluctuating energy sources such as wind energy. ED was consequently coupled to a wind turbine system and a series of desalination tests were performed over a wide range of wind speeds (2-10 m/s), turbulence intensities (TI of 0-0.6) and oscillation periods (0-180 s). Results showed that water production and SEC increased with wind speed. However, both the water production and SEC stopped increasing as the power output from the turbine levelled off at wind speeds above the rated value (vrated: 7.9 – 8.4 m/s). The impact of wind speed fluctuations on the system performance were insignificant up to a TI of 0.4. The desalination performance declined under high turbulence intensity fluctuations (TIs ≥ 0.5) and long periods of oscillation (> 40 s), as the wind-ED system periodically cycled off in response to operation below the cut-in wind speed of the wind turbine (vcut-in: ~ 2 m/s). The off-cycling of the system caused significant delays in the desalination process, and thus resulted in reduced water production. Further reduction in the water production resulted as the wind-ED system operated under intermittent wind speed conditions with off-wind periods longer than 10 s. It was concluded that the main challenge in direct coupling of ED to a wind resource was not the magnitude of the fluctuations but the impact of the power cycling off during long periods of oscillation and lengthy periods of no wind. Interestingly, the SEC of the process remained relatively unaffected by the fluctuations and intermittencies in the wind resource. The effect of energy fluctuations on the competitive transport of F-, Cl-, NO3- and SO42- from artificial brackish water (TDS ~4350 mg/L) was investigated using different sets of real wind data. The ion removal, independent of the wind regime tested, followed the order: NO3- ≥ Cl- > F- > SO42-. The competitive removal of the ions was linked to differences in physicochemical properties (i.e. hydration energy, ionic mobility and valence). The specific selectivity (e.g. preferential transport of NO3- over SO42- ions) was found to increase with concentration polarisation being either minimised (by lowering the mean wind speed) or disrupted (by fluctuations in the wind resource). The results from flow rate and feed concentration experiments, showed that power production of the wind turbine depended on not only the available wind energy but also the resistance of the load (i.e. the ED stack). Thus, increasing the feed concentration and the flow rate resulted in reduced resistance in the ED stack (Rstack), which inversely influenced the current induction counter torque force applied on the shaft of the wind turbine and caused the rotor to spin at a lower angular velocity. This led to increased sensitivity of the wind-ED system to wind speed fluctuations (e.g. system cycled off due to extreme fluctuations and intermittencies with low TDS feed concentration of 2400 mg/L) and hence a reduction of desalination performance. Impact of flow rate on the SEC was found to be negligible; this was attributed to the automatic voltage to current adjustments done by the wind turbine, in order to minimise the impacts of Rstack on the power production by the turbine at a given wind speed. Increased flow rate and resulting shrinkage of the boundary layer’s thickness, caused the concentration profiles at the solution-membrane interface to become steeper. This favoured the transport of ions with the highest diffusion coefficients in the mixture (i.e. Cl- and NO3-). Decreased flow rate favoured the transport of ions with larger valence numbers and higher electric mobility inside the electrolyte (i.e. SO42-); as the former property governed the faster migration of SO42- ions through the thick boundary layer and the latter property assisted with the improved affinity of the ion-exchange membrane to SO42- ions compared to the monovalent anions in the mixture. Increasing the feed concentration of Cl- from 500 to 2,550 mg/L led to reduced transport numbers for the other anions in the mixture and significantly reducing their removal rate. The results obtained from both the pulsed-ED and wind-ED experiments showed that, despite direct coupling to the fluctuating energy source the SEC of the process remained relatively unaffected by the energy fluctuations. Although the desalination process might require more time to be completed when operating under extreme wind speed fluctuations and intermittencies, the quality of the drinking water produced was always within the WHO standards. In conclusion, the findings from this research prove the wind-ED system to be an energetically robust and a reliable off-grid desalination technique suitable for the treatment of brackish groundwater in water stressed remote regions.
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Získávání a výběr pracovníků banky se zaměřením na využití metod Assessment Centre / Recruitment and selection of employees of the bank focusing on the methods of Assessment CentreZobaníková, Iveta January 2010 (has links)
Final thesis concentrates on the issues of recruitment and selection of employees with emphasis on the method Assessment Centre. It consists of a description of this process in ČSOB and moreover it examines the differences between internal and external form of AC. A fluctuation of employees who are chosen by this way is used as an evaluation criterion of propriety of a selection method.
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Mutation rates in mycobacterial hosts with altered Dna metabolic activityBarichievy, Samantha 08 February 2006 (has links)
Master of Science - Molecular Medicine and Haematology / The completion of the genome sequence of Mycobacterium tuberculosis strain H37Rv revealed that 10% of the coding capacity is devoted to two, large multigene families that are characterised by repeat sequences. These are the PE and PPE families that code for acidic, glycine rich proteins. A subgroup of the PE family is the polymorphic GC rich sequence (PGRS) gene subfamily. Genome comparisons of clinical isolates of M. tuberculosis have confirmed the polymorphic character of some of these genes suggesting they may be analogous to the contingency loci found in other pathogenic
bacteria. Certain PE-PGRS proteins play a direct role in virulence in M. marinum, other PE-PGRS genes are cell surface associated, and some PE-PGRS proteins are variable surface antigens, supporting a potential role in host pathogen interactions. A reporter assay designed to investigate mutations in a PE-PGRS repeat-containing sequence was used to assess mutation rates in various M. smegmatis host strains by fluctuation analysis. A wide spectrum of mutations was observed and the evidence suggests
that slipped-strand mispairing between proximal and distal PGRS sequences located in cis is the
predominant type of mutational event at such loci. Moreover, slipped-strand mispairing at such loci occurs at a moderately higher rate than base substitution mutagenesis and is mediated by the normal replicative polymerase.
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Padrão de sobreposição e co-ocorrência interespecífica de moscas-das-frutas (Diptera, Tephritidae, Anastrepha) em áreas antropizadas / Overlap pattern and interespecific co-ocurrence of fruit flies (Diptera, Tephritidae, Anastrepha) in anthropic areasAmaral, Tayron Sousa 11 March 2014 (has links)
O padrão de sobreposição de nicho e a co-ocorrência, bem como as interações positivas e negativas entre espécies de Anastrepha, com base em matrizes com dados de abundância e presença-ausência, foi avaliado. As populações de Anastrepha foram estudadas também quantativamente para avaliar sua distribuição e a flutuação populacional das espécies predominantes. O estudo foi realizado em duas áreas antropizadas, denominadas Fazenda Areão e Monte Olimpo, do campus \"Luiz de Queiroz\", Universidade de São Paulo, Piracicaba, SP. O estudo foi baseado em 52 coletas por meio de 14 armadilhas tipo McPhail distribuídas nas duas áreas. Foram coletadas 1.583 fêmeas pertencentes a 14 espécies: A. amita Zucchi, A. barbiellinii Lima, A. bistrigata Bezzi, A. daciformis Bezzi, A. distincta Greene, A. fraterculus (Wiedemann), A. grandis (Macquart), A. manihoti Lima, A. montei Lima, A. obliqua (Macquart), A. pickeli Lima, A. pseudoparallela (Loew), A. serpentina (Wiedemann) e A. sororcula Zucchi. Na Fazenda Areão, foram coletadas mais espécimes (1.041), em comparação ao Monte Olimpo (542), que, entretanto, apresentou o maior índice de diversidade de espécies. Anastrepha fraterculus, A. obliqua e A. pseudoparallela foram predominantes na Fazenda Areão; no Monte Olimpo, apenas A. fraterculus e A. pseudoparallela foram predominantes. A média de sobreposição de nicho foi maior que o esperado ao acaso para as duas áreas, portanto, os nichos ecológicos das espécies, em grande parte, se sobrepõem. O padrão de co-ocorrência indicou a ocorrência de dois pares de espécies não aleatórios que segregaram: A. pseudoparallela x A. obliqua na Fazenda Areão e A. fraterculus x A. pseudoparallela no Monte Olimpo. A segregação indica que pode haver competição por algum recurso dentro do nicho. A análise também apresentou três pares agregados: A. bistrigata x A. montei e A. fraterculus x A. barbiellinii para a Fazenda Areão e A. fraterculus x A. bistrigata para o Monte Olimpo, indicando que cada par coexiste pacificamente, sem que haja interferência na permanência das populações de moscas-das-frutas nas áreas. O nível populacional mais elevado ocorreu de agosto a dezembro, nas duas áreas, quando as temperaturas oscilaram entre 18 e 24°C, com pico populacional em setembro. / The niche overlap pattern and co-ocurrence, as well as positive and negative interactions among Anastrepha species, based on abundance matrix data and presence-absence data was evaluated. The populations of species of Anastrepha was analyzed quantitatively to evaluate its distribution and the populational fluctuation of predominant species. The study was carried out in two anthropic areas, Fazenda Areão and Monte Olimpo, at \"Luiz de Queiroz\" campus, Universidade de São Paulo, Piracicaba, SP. The research was based on 52 samplings obtained over 14 McPhail traps distributed in these two areas. It was captured 1,583 females belong 14 species: A. amita Zucchi, A. barbiellinii Lima, A. bistrigata Bezzi, A. daciformis Bezzi, A. distincta Greene, A. fraterculus (Wiedemann), A. grandis (Macquart), A. manihoti Lima, A. montei Lima, A. obliqua (Macquart), A. pickeli Lima, A. pseudoparallela (Loew), A. serpentina (Wiedemann) and A. sororcula Zucchi. It was collected more specimens (1,041) at Fazenda Areão, comparing with the ones at Monte Olimpo (542), that showed the highest species diversity index. Anastrepha fraterculus, A. obliqua and A. pseudoparallela were the predominant species at Fazenda Areão; at Monte Olimpo, only A. fraterculus and A. pseudoparallela were predominant. The niche overlap mean was higher than randomly expected for these two areas. Therefore, the species ecological niches mostly overlap. The coocurrence pattern indicated the ocurrence of two non-randomized pair of species that segregated: A. pseudoparallela x A. obliqua at Fazenda Areão, and A. fraterculus x A. pseudoparallela at Monte Olimpo. The segregation indicates that can exist three aggregated pairs: A. bistrigata x A. montei and A. fraterculus x A. barbiellinii at Fazenda Areão; and A. fraterculus x A. bistrigata at Monte Olimpo, indicating that each pair coexists pacifically, with no interference in the permanence of the fruit fly populations in the areas. The highest populational level occurred from August to December, when temperatures oscillated between 18 and 24°C, with the population peak in September.
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Amarelo da ameixeira: Modelo de colonização do hospedeiro por um fitoplasma associado à doença / Plum yellow: colonization model of the host by a phytoplasma associated with this diseaseGalvão, Sarah Rodrigues 18 January 2016 (has links)
A cultura da ameixeira vem despertando a atenção de produtores brasileiros, pois oferece alta rentabilidade, possibilita a prática da agricultura familiar, emprega mão de obra, recebe incentivos de programas oficiais e conta com um mercado altamente promissor. No entanto, a cultura ainda necessita de cultivares com melhor adaptação climática, qualidade de frutos e resistência às doenças. Atualmente, dentre as doenças, o \"amarelo das fruteiras de caroço\", associada a um fitoplasma, vem causando sérios problemas. Em 2013, em pomares comercias de ameixeira (Prunus salicina), instalados em Paranapanema (SP), foram observadas plantas portadoras de sintomas tipicamente induzidos por fitoplasmas, caracterizados por superbrotamento de ramos, redução no comprimento de entrenós, além de amarelecimento, deformação e redução do tamanho de folhas. Nestas plantas foi identificado um fitoplasma pertencente ao grupo 16SrI-B (Candidatus Phytoplasma asteris). Visando aumentar os conhecimentos sobre este patossistema, o objetivo desse trabalho foi estudar a dinâmica da colonização de plantas comerciais de ameixa infectadas pelo fitoplasma. Para isso, em dois pomares, amostras da parte aérea e raiz de plantas sintomáticas, pertencentes às variedades Gulfblaze e Azteca, foram coletadas mensalmente, durante um ano. O DNA total foi extraído e submetido ao PCR em tempo real para quantificar o fitoplasma nos tecidos do hospedeiro. Nessas reações foram utilizados os iniciadores universais UniRNAForward/UniRNAReverse. O fitoplasma foi detectado em todas as amostras, tanto aquelas da parte aérea quanto de raízes, em ambas as variedades estudadas. A concentração do patógeno nos tecidos do hospedeiro variou de 5,3 x 103 a 4,54 x 106 e 3,28 x 103 a 1,28 x 106 número de cópias/100ng de DNA total, na parte aérea e nas raízes, respectivamente. Os resultados mostraram uma flutuação sazonal na concentração do fitoplasma, onde as maiores concentrações foram encontradas nas épocas mais quentes do ano, principalmente no mês de dezembro, e uma redução na concentração do patógeno foi observada nas épocas mais frias, embora o fitoplasma tenha permanecido na parte aérea da planta durante a fase de dormência do hospedeiro. A variedade Gulfblaze apresentou maior concentração do patógeno comparada com a variedade Azteca. O fitoplasma associado ao amarelo da ameixeira também foi encontrado em maior concentração na copa da planta. Com base nos resultados, amostras retiradas da parte aérea e nas épocas mais quentes do ano são as mais indicadas para os procedimentos de detecção do patógeno, visando uma diagnose mais confiável. / Plum is a crop that has aroused the attention of Brazilian growers due to high profitability, family farming, incentive arrangement and promising market. However the plum culture still need of varieties with good climate adaptation, best quality fruit, and disease resistance. Currently, among the diseases, stone fruit yellows, associated with a phytoplasma have caused serious problems. In 2013, in commercial orchards of plum (Prunus salicina) located in Paranapanema (SP), plants were observed exhibiting symptoms typically induced by phytoplasmas, characterized by witches broom and shortened internodes. Besides, the leaves were yellowish, malformed, and reduced in size. In these plants was identified a phytoplasma belonging to the group 16SrI-B (Candidatus Phytoplasma asteris). The aim of the present work was to study the dynamics of colonization of commercial plants plum by the phytoplasma, in order to better understanding of the disease. Thus, in two orchards, samples from aerial parts and roots of symptomatic plants belonging to Gulfblaze and Azteca varieties were collected monthly, during a year. Total DNA was extracted and submitted to the Real Time PCR to quantify the phytoplasma in host tissues. In these reactions the universal primers UniRNAForward/UniRNAReverse were used. The phytoplasma was detected in all samples, both aerial parts and roots of the two varieties. The concentration of the pathogen in host tissues ranged from 5,3 x 103 to 4,54 x 106 and 3,28 x 103 to 1,28 x 106 number of copies/100 ng of total DNA in aerial parts and roots, respectively. The results showed a seasonal fluctuation in the concentration of phytoplasma. The highest concentrations were found in the warmer seasons of the year, especially in December, and a reduction in pathogen concentration was observed when the weather was milder, although the phytoplasma remained in aerial part of the plant during the dormant phase of the host. The Gulfblaze variety showed a higher concentration of the pathogen compared with the Azteca variety. In addition, the phytoplasma associated with the disease was found in highest concentration in the aerial part of plant. Based on the results, samples collected from the aerial part and in the warmer seasons of the year are the most recommended for pathogen detection procedures for safe diagnosis.
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Recarga de aquífero em área urbana: estudo de caso de Urânia (SP) / Urban aquifer recharge: case study in Urânia (São Paulo State, Brazil)Maldaner, Carlos Henrique 06 October 2010 (has links)
Este projeto visou quantificar e determinar a origem da recarga do aquífero freático na zona urbana do município de Urânia (SP). A área está localizada no extremo noroeste do Estado de São Paulo, sobre sedimentos arenosos da Formação Vale do Rio do Peixe, do Grupo Bauru. A metodologia usada foi de balanço hídrico e variação de nível de água para a quantificação da recarga e técnicas hidroquímicas e isotópicas para o estudo de origem da água. Foram analisadas águas da chuva, poços cacimbas, poços tubulares, poços que exploram o Aquífero Bauru e Sistema Aquífero Guarani, esgoto e água distribuída pela SABESP. O clima na região é dividido em duas estações: a úmida, de outubro a maio, e a seca, de junho a setembro. A precipitação acumulada, entre setembro de 2007 e agosto de 2008, foi de 2498 mm. Pelo método do balanço hídrico, 10% deste total (247 mm) correspondem ao escoamento superficial, 69% (1734 mm) voltam diretamente à atmosfera por evapotranspiração, restando 21% (517 mm) para recarga. Através do método de variação do nível d´água, monitorado em dois poços de profundidades distintas, foi calculada a recarga para o período de setembro de 2008 a abril de 2010. O volume de precipitação registrado foi de 2742 mm, e a recarga calculada somou 20% deste total (544 mm) para o poço mais raso, e 16% (456 mm) para o mais profundo. Os dados de nível de água mostraram também que apenas chuvas maiores de 100 mm por mês são capazes de elevar os níveis de água. Através da coleta de amostras mensais de chuva para análises de isótopos estáveis de oxigênio e hidrogênio foi determinada a reta meteórica local (D = 8,5 18O + 17 ( VSMOW)). Através dos isótopos estáveis de oxigênio e hidrogênio foi possível definir que a recarga da água subterrânea é predominantemente proveniente da água de chuva, podendo ter contribuição pequeno proveniente de vazamentos da rede de água da SABESP e do esgoto. Os isótopos radiogênicos de chumbo não mostraram nenhum resultado significativo para o estudo de origem da água subterrânea. Os resultados dos isótopos radiogênicos de estrôncio e de hidroquímica indicaram a existência de um zoneamento do aquífero, que pode ser dividido em raso, intermediário e profundo. Isto possibilita a identificação da contribuição de cada zona para os poços tubulares. A maioria das amostras apresentou contribuição menor do que 8% da água classificada hidroquimicamente e isotopicamente como rasa, e o restante de água profunda. Porém a contribuição pode chegar a 49% de água rasa, indicando alta vulnerabilidade à contaminação. Portanto, os isótopos de estrôncio tem potencial para ser uma ferramenta importante em estudos de vulnerabilidade e gestão de águas subterrâneas. / The focus of this project is to identify the source and quantify the recharge of the unconfined portion of the Bauru aquifer, present in the urban area of Urania, a small city located at the northwestern corner of São Paulo State, Brazil. The aquifer is composed by sandy sediments of the Vale do Rio do Peixe Formation, Bauru Group. Water balance and water table fluctuation were used to quantify the recharge. Hydrochemistry and isotopes, both stable and radioactive, were used to determine recharge sources. Rain water samples were collected, as well as from shallow and deep wells taping the Bauru aquifer and the confined Guarani Aquifer System (GAS), and from the public water supply system, which is a mixture of both aquifers. Climate is tropical, with two well defined seasons: the humid, from October to May, and the dry, from June to September. The total accumulated precipitation between September 2007 and august 2008 was 2498 mm. Using the water balance method, runoff accounted for 10% of this amount (247 mm), evapotranspiration 69% (1734 mm) and recharge 21% (517 mm). Water table was monitored in two wells with different depths in the unconfined aquifer, between September 2008 and April 2010. The total precipitation during this period was 2742 mm. Using the water table fluctuation method, recharge in the shallower well was 20% of this total (544 mm), and 16% in the deeper well (456 mm). Only rainfalls in excess of 100 mm/month caused an elevation in the water table. The local meteoric line was established (D = 8,5 18O + 17 ( VSMOW)). The stable hydrogen and oxygen isotopes indicated that the main recharge source is rainfall, and a secondary source is leakage from water and sewage mains. Radioactive Pb isotopes were not useful for recharge source definition. Water samples collected at different depths in gravel-packed wells show both distinctive radioactive Sr isotope and hydrochemical signatures. Thus, groundwater can classified as shallow, intermediary and deep. Most samples collected at gravel-packed wells had less than 8% of water coming from the shallow zone, but a few wells had up to 49% of shallow water, which indicates high vulnerability to contaminants. Therefore, Sr isotopes may be used as a tool in unconfined aquifer vulnerability assessments.
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[en] CONSIDERATIONS ABOUT THE FLUCTUATION IN THE USE OF THE SUBJUNCTIVE IN ORAL CONTEXTS OF BRAZILIAN PORTUGUESE / [pt] CONSIDERAÇÕES SOBRE A FLUTUAÇÃO NO EMPREGO DO SUBJUNTIVO EM CONTEXTOS ORAIS DO PORTUGUÊS DO BRASILJUSSARA REGINA GONCALVES 10 October 2003 (has links)
[pt] Neste trabalho, desenvolvemos uma análise da flutuação
existente no emprego do subjuntivo em contextos orais do
Português do Brasil, com ênfase na variação
subjuntivo/indicativo. Tomando por base a perspectiva de
linguagem e gramática oferecida nos desenvolvimentos
teóricos da Lingüística Cognitiva, notadamente as
proposições de G. Lakoff acerca dos efeitos de prototipia
nas categorias gramaticais e as de E. Sweetser sobre a
precedência cognitiva da modalidade deôntica em relação à
epistêmica, examinamos situações de flutuação,
apresentando
um mapeamento dos casos e levantando diferentes fatores
motivantes envolvidos. O trabalho fornece elementos para
uma caracterização semântico-pragmática e morfossintática
do que seriam os usos mais prototípicos do subjuntivo em
Português, argumentando em favor da tese de que a
flutuação
não é aleatória, incidindo com maior freqüência em
empregos
menos prototípicos dessa categoria gramatical. / [en] This study analyses the existing fluctuation in the use of
the subjunctive mood in oral contexts of Brazilian
Portuguese, with emphasis on the subjunctive/indicative
alternation. Based on the theoretical perspective on
language and grammar that is offered in Cognitive
Linguistics, notably G. Lakoff`s propositions concerning
prototype effects in grammatical categories and
E. Sweetser`s propositions on the cognitive precedence of
the deontic modality in relation to the epistemic, the
study investigates the situations of fluctuation,
mapping out the cases and showing different motivating
factors involved. Elements for a semantic-pragmatic and
morphosyntactic characterization of prototypical uses of
the subjunctive mood in Portuguese are supplied, and the
case is made for the thesis that the fluctuation is not
random, occurring more often in less prototypical uses of
this grammatical category.
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Nonequilibrium fluctuations of a Brownian particle / Fluctuations hors-équilibre d'une particule BrownienneGomez-Solano, Juan Rubén 08 November 2011 (has links)
Ces travaux de thèse présentent une étude expérimentale des fluctuations d'une particule Brownienne soumise à deux différentes conditions hors-équilibre dans un fluide . Le but est de comprendre d'une manière générale la relation entre les fluctuations spontanées, la fonction de réponse linéaire et la production totale d'entropie des processus loin de l'équilibre thermique. La première partie est consacrée à l'étude du mouvement d'une particule colloïdale dans un état stationnaire périodique hors-équilibre induit par une force non-conservative et à sa réponse à une perturbation externe. Nous analysons la dynamique du système dans le contexte des différentes approches généralisées de fluctuation-dissipation. Nous montrons que ces relations théoriques sont satisfaites par les données expérimentales quand on prend en compte le rôle du courant du à la rupture du bilan détaillé. Dans une deuxième partie nous étudions les fluctuations et la réponse d'une particule Brownienne dans deux types de bains vieillissants qui relaxent vers l'équilibre thermique: un verre colloïdal de Laponite et une solution aqueuse de gélatine. Dans ce cas-là nous montrons que le flux de chaleur de la particule vers le bain pendant sa relaxation représente une correction hors-équilibre du théorème de fluctuation-dissipation. Donc, le flux de chaleur joue le même rôle que le courant dans un état stationnaire. En conséquence, les résultats de la thèse mettent en évidence l'importance générale de la production totale d'entropie pour quantifier les relations de fluctuation-dissipation généralisées dans les systèmes hors-équilibre. / This thesis describes an experimental study on fluctuations of a Brownian particle immersed in a fluid, confined by optical tweezers and subject to two different kinds of non-equilibrium conditions. We aim to gain a rather general understanding of the relation between spontaneous fluctuations, linear response and total entropy production for processes away from thermal equilibrium. The first part addresses the motion of a colloidal particle driven into a periodic non-equilibrium steady state by a nonconservative force and its response to an external perturbation. The dynamics of the system is analyzed in the context of several generalized fluctuation-dissipation relations derived from different theoretical approaches. We show that, when taking into account the role of currents due to the broken detailed balance, the theoretical relations are verified by the experimental data. The second part deals with fluctuations and response of a Brownian particle in two different aging baths relaxing towards thermal equilibrium: a Laponite colloidal glass and an aqueous gelatin solution. The experimental results show that heat fluxes from the particle to the bath during the relaxation process play the same role of steady state currents as a non-equilibrium correction of the fluctuation-dissipation theorem. Then, the present thesis provides evidence that the total entropy production constitutes a unifying concept which links the statistical properties of fluctuations and the linear response function for non-equilibrium systems either in stationary or non stationary states.
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Monitoramento de moscas-das-frutas (Diptera, Tephritidae, Anastrepha) em nove municípios do Estado do Valle del Cauca, Colômbia / Monitoring of fruit flies (Diptera, Tephritidae, Anastrepha) from nine municipalities of the state of the Valle del Cauca, Colombia.Jaramillo, Marisol Giraldo 10 December 2007 (has links)
Neste estudo, são discutidas as moscas-das-frutas coletadas nos monitoramentos realizados pelo Instituto Colombiano Agropecuário (ICA), em nove municípios do estado do Valle del Cauca (Andalucia, Caicedonia, La Unión, Restrepo, Roldanillo, Sevilla, Toro, Tulúa e Zarzal), em diversas culturas (goiaba, mamão, café, laranja, pitahaya, etc.). Este estudo teve por objetivos: (1) identificar as espécies de Anastrepha e (2) analisar as populações das espécies mais freqüentes e numerosas. As moscas foram coletadas em armadilhas plásticas ou de vidro tipo McPhail com atrativo alimentar (proteína hidrolisada) por dois anos (janeiro de 2004 a dezembro de 2005). Nos nove municípios, foram capturadas 1.794 fêmeas de Anastrepha, sendo identificadas dez espécies: Anastrepha distincta Greene, 1934, A. grandis (Macquart, 1845), A. pallidipennis Greene, 1934, A. fraterculus (Wied., 1830), A. obliqua (Macquart, 1835), A. leptozona Hendel, 1914, A. mucronota Stone, 1942, A. serpentina (Wied., 1830), A. manihoti Lima, 1934 e A. striata Schiner, 1868. Anastrepha fraterculus foi a espécie mais freqüente (49% do total das capturas), seguida por A. striata (39,5%) e A. obliqua (7%). As sete espécies restantes, em conjunto representaram apenas 4,5% do total capturado. Anastrepha striata e A. obliqua foram coletadas nos nove municípios. Anastrepha striata foi a mais numerosa nos pomares comerciais de goiaba. Anastrepha fraterculus foi coletada em cinco municípios, mas 90% dos seus exemplares foram coletados em Sevilla e nenhum exemplar foi coletado em Roldanillo, La Unión e Toro. Esses municípios fazem parte da área selecionada para o estabelecimento do systems approach, visando à exportação de mamão aos EUA, por apresentarem áreas de baixa prevalência de A. fraterculus. Em Sevilla, foi coletado o maior número de espécies, sendo três coletadas apenas nos locais amostrados nesse município (A. distincta, A. manihoti e A. serpentina). Anastrepha leptozona e A. pallidipennis foram coletadas apenas em Toro. / This work was based on fruit flies collected during the monitoring conducted by the Instituto Colombiano Agropecuario (ICA) in nine municipalities of the Valle del Cauca province (Andalucia, Caicedonia, La Union, Restrepo, Roldanillo, Sevilla, Toro, Tulua, and Zarzal), on several crops (guava, papaya, coffee, orange, pitahaya, among others). This study had the following objectives: 1) to identify the species of Anastrepha, and 2) to analyze the populations of the most frequent and abundant species. The fruit flies were collected in plastic or glass McPhail type traps with feeding attractant (protein hydrolysate) during two years (from January, 2004 to December, 2005). In the nine municipalities, 1,794 females of Anastrepha of the following species were captured: Anastrepha distincta Greene, 1934, A. grandis (Macquart, 1845), A. pallidipennis Greene, 1934, A. fraterculus (Wied., 1830), A. obliqua (Macquart, 1835), A. leptozona Hendel, 1914, A. mucronota Stone, 1942, A. serpentina (Wied., 1830), A. manihoti Lima, 1934 and A. striata Schiner, 1868. Anastrepha fraterculus was the most frequent species captured (49% of the total captures), followed by A. striata (39.5%) and A. obliqua (7%). The other seven species accounted only for 4.5% of the total captures. Anastrepha striata and Anastrepha obliqua were captured in all nine municipalities Anastrepha striata was the most abundant on guava crops. Anastrepha fraterculus was collected in five municipalities, but 90% of the specimens were captured in Sevilla and none in Roldanillo, La Union or Toro. The former municipalities are part of the area selected to establish a systems approach under which papaya will be exported to the USA, since they bear areas of low prevalence for A. fraterculus. The highest number of species was captured in Sevilla, three were collected only in sites sampled in this municipality (A. distincta, A. manihoti, and A. serpentina). Anastrepha leptozona and A. pallidipennis were captured only in Toro.
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