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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Chov ryb v biofloc systému / Fish farming in biofloc system

LUNDA, Roman January 2014 (has links)
The aim of this diploma thesis has been to establish and to verify functionality of a model biofloc system for Nile tilapia (Oreochromis niloticus) farming. The main criteria to be observed during the experiment were chemical characteristcs of the water, development of the biofloc microflora and the reaction of the system to technological interventions. The experiment has consisted of two phases. The first phase monitored an insufficiently functioning system. Due to unsatisfactory assurance of the oxygen concentration as well as the water column stirring, 4 different types of air-sourcing devices have been used in the experiment. For assuring of the perfect stirring and of the sufficient oxygen concentration ( 6 mg×l-1) an airlift fulfilling both the criteria has been constructed. The impact of the carbohydrates application on the decrease of the amonia nitrogen has been sucessfully verified during the experiment. The average value of the C/N ratio of 14 has been reached thanks to the quantity of flour being added as the carbohydrate source into the system. When the recommended amount of TSS (200 ml×l-1) with the corresponding biofloc microflora that has been transforming all the nitrogen in the experiment tank into the microbial protein, the system was evaluated as fully functional. During the biofloc analysis, the presence of N-substances at the amount of 223.6 g at all of the experiment tank (1300 l) has been detected. In the comparison with the applied feed material at the amount of 300 g containing 39% of the N-substances, only 67.1 g of the N-substances has been added into the system. The biofloc (bacterial flakes) serves as food for the tilapia during the entire period of the functional system.
22

Evaluation of an Exfiltration Trench for Treatment of Highway Storm Water Runoff

Al-Tarawnah, Ahmad M. 24 September 2013 (has links)
No description available.
23

Reusable rainwater quality at Ikorodu area of Lagos, Nigeria: Impact of first-flush and household treatment techniques

John, Chukwuemeka K., Pu, Jaan H., Moruzzi, R., Pandey, M., Azamathulla, H. Md. 24 March 2022 (has links)
Yes / Water scarcity is a huge problem in Africa, and hence rainwater becomes a crucial water source for fulfilling basic human needs. However, less attention has been given by African countries to the effectiveness of common rainwater treatments to ensure the population's health. This study investigates the impact of different household treatment techniques (HHTTs), i.e. treatments by chlorine, boiling, alum, and a combination of alum and chlorine, on its storage system using a case study at the Ikorodu area of Lagos state, which is a rural area in Nigeria. The first-flush quality has been particularly studied here, where the microbial reduction through its practice has been examined from five different roofs. One of the investigated roofs was from a residential building, and four were constructed for the purpose of this study. In this study, the physical parameters (i.e. total suspended solids and turbidity) and the microbial parameters (i.e. total coliform and Escherichia coli) of the collected rainwater have been investigated. From the results, it has been observed that: (1) the water quality at the free phase zone is better than that at the tank's bottom; (2) the combination of chlorine and alum gives the best rainwater quality after comparing the application of different HHTTs; and (3) a reduction of about 40% from the original contaminant load occurs in every 1 mm diversion. / Hidden Histories of Environmental Science Grant Project (at Seed-grant Stage), funded by the Natural Environment Research Council (NERC) and Arts and Humanities Research Council (AHRC), part of UK Research and Innovation (UKRI)
24

Tecken som stöd (TSS) : En intervjustudie kring pedagogers inkluderande arbetssätt i lågstadiet.

Högö, Urban January 2023 (has links)
Hälften av pedagogerna i studien har erfarenheter av tecken som stöd (TSS). Logopeden och specialpedagogen som deltog i studien besitter ytterligare centrala kunskaper inom den språkliga inlärningen som är betydande för barnens fortsatta språkutveckling. Av de pedagoger som saknade erfarenhet av TSS, finns en vilja att möta dessa elever i skolan och önskan att gå utbildning.I klassrummen finns olika material tillgängliga, vissa har pedagogerna utformat själva medan andra finns digitalt tillgängliga. Materialet kan bestå av exempelvis bildstöd. Det visar sig bero på elevernas behov och förutsättningar. TSS används även för att bredda språkkunskaperna hos de elever som har ett annat modersmål än svenska, oavsett ålder, etnicitet osv. Av det material som finns i klassrummet riktat till TSS, avviker på de olika skolorna. Resultatet visar att pedagogerna har olika arbetssätt gällande detta material. Vissa arbetsgrupper som arbetar inom jämlika åldersspann använder materialet på olika vis. Undersökningen visar även på att ett av klassrummen istället tagit bort sina anpassningar för att anpassa klassrummet för en elev med NPF problematik.Studien visar på diskrepanser mellan arbetssätt, erfarenheter och elevmöten. Dock delar alla pedagoger en positiv inställning till att möta dessa elever i klassrummet.Pedagogerna är även samstämmiga att TSS är ett hjälpmedel som kan hjälpa flertalet elever i sin språkutveckling och delar gärna med sig av sin kunskap till andra som är villiga att hjälpa och stötta dessa elever i klassrummet.
25

Impacts of sedimentation on rainwater quality: case study at Ikorodu of Lagos, Nigeria

John, Chukwuemeka K., Pu, Jaan H., Pandey, M., Moruzzi, R. 08 April 2021 (has links)
Yes / This study investigated the impact of sedimentation on rainwater storage system using a case study at the Ikorodu area of Lagos state, a rural area in Nigeria. In this investigation, the proportions of Escherichia coli (E. coli) that were settleable (due to sedimentation) and those that were at the free phase have been studied. Water samples were collected from different depths in the inspected rainwater storage tank at two different periods (i.e. rainy and dry periods) for 20 days. The samples collected from these periods have been analysed for physical and microbial measures before passing it through the serial filters with pore sizes of 500 μm, 100 μm, 10 μm and 1.5 μm to measure the retained particle mass. From the results, it was observed that: (1) the water quality at the free-phase zone was better than that at the tank’s bottom; (2) the settleable bacteria rapidly sinked to bottom; (3) the correlation of turbidity, E. coli and total suspended solids (TSS) for all the rain events showed a relatively high Pearson’s coefficient of 0.9 to one another; and (4) over 70% of settling TSS occurred within first 36 hours. Finally, it has been found that the physical sedimentation process can significantly reduce the microbial measures.
26

Transcriptoma, sítios de ligação para fatores de transcrição e região promotora de cana-de-açúcar / Transcriptome, transcription factors binding sites, and sugarcane promoter region

Oliveira, Mauro de Medeiros 26 September 2018 (has links)
O Brasil tem a maior produção de cana-de-açúcar do mundo. O cultivo de cana-de-açúcar no Brasil está voltado principalmente para a produção de açúcar ou Etanol e nos últimos anos para a produção de bioeletricidade através da utilização da biomassa do bagaço e da palha. Apesar da importância econômica e do potencial sustentável que a cana-de-açúcar apresenta, o genoma de referência para esta cultura ainda não está disponível na literatura. A principal justificativa para isso está na complexidade do mesmo, em especial pela alopoliploidia e autopoliploidia. De fato esta característica é a principal barreira para o desenvolvimento de novas variedades comerciais. Na literatura há diferentes estratégias que visam contribuir com o conhecimento genômico de cana-de-açúcar sendo mais prevalente dados de transcriptoma e pouca informação sobre o processo de regulação gênica. Além disso, diferente do que é observado em outras culturas comerciais, em cana-de-açúcar não há trabalhos associados com a caracterização in silico da região Promotora, assim como na identificação de sítios de ligação para Fatores de Transcrição (TFBSs). Por esta razão, o nosso trabalho foi direcionado para a caracterização in silico de regiões regulatórias em cana-de-açúcar. Para esta tarefa nós realizamos apenas a rotulação de sequências de DNA não codificante que estavam a upstream de cada gene anotado em cana-de-açúcar. Todos os genes foram selecionados de dados de transcriptoma e a sequência de DNA da região Promotora foi isolada do Genespace de cana-de-açúcar SP80-3280 gerado pelo projeto de sequenciamento do genoma de referência do nosso grupo. A rotulação da região regulatória em cana-de-açúcar foi executada em duas subsequências: Core Promoter e Promotor Proximal. Na região Core Promoter nós realizamos a identificação do sítio de inicio de transcrição (TSS), a estimativa do tamanho da região 5\' UTR e a classificação da região Core Promoter em TATA-box ou TATA-less. Todos os processos foram realizados através da ferramenta TSSPlant. A utilização da ferramenta TSSPlant motivou o desenvolvimento de uma nova ferramenta para predição do sinal de TSS que aqui chamamos de TSSFinder. A ferramenta TSSinder apresentou resultados de predição do sinal de TSS superior aos seus pares, além disso esta ferramenta foi bem sucedida em diferentes organismos como Arabidopsis thaliana, Gallus gallus e Saccharomyces cerevisiae. Na região Promotora Proximal nós realizamos a identificação de TFBSs através de duas metodologias: predição de novo e mapeamento de matrizes de TFBS (PSSM). O processo de predição de novo foi realizada por meio de dois modelos: Maximização da expectativa e Gibbs Sampler e esse processo foi executado apenas para o subgrupo de genes co-expressos ou apenas para o conjunto de sequências homeólogas de cada gene de cana-de-açúcar selecionado. Para o restante das sequências foi realizado apenas o mapeamento das matrizes de TFBSs identificadas durante o processo de predição de novo. Em paralelo todos TFBSs identificados no nosso trabalho foram comparados com o banco de TFBS para plantas. Através desse procedimento foi possível estimar qual classe de Fator de Transcrição está interagindo com o TFBS identificado na região Promotora Proximal dos genes Scdr1, ScSuSy, ScPAL. Com este trabalho, nós cobrimos parte da lacuna observada em estudos in silico paras regiões regulatórias de cana-de-açúcar. Além disso, nós aperfeiçoamos o processo de identificação do sinal de TSS para diferentes organismos; inclusive para plantas Dicotiledôneas e Monocotiledôneas. / Brazil has the highest production of sugarcane in the world. Its cultivation in Brazil is aimed at producing of sugar or ethanol and in recent years, biomass for bioenergy from bagasse and straw. Despite the economic importance and the sustainable potential that sugarcane presents, a reference genome for this crop is not yet available in the literature. One justification for this absence lies in the sugarcane genome complexity, allopolyploidy and autopolyploidy. In fact these characteristics are the main barrier for the development of new commercial varieties. In the literature different strategies aimed at contributing to genomic sugarcane mostly on the transcriptome and little information on the process of gene regulation. Furthermore, unlike other commercial crops, sugarcane has no reported in silico characterization of its promoter regions and identification of Transcription Factor binding sites. For this reason, our work was directed to an in silico characterization of regulatory regions in sugarcane. For this task we performed the labeling of non-coding DNA sequences that were upstream of each gene annotated in sugarcane. All genes were using from transcriptome data and the promoter region DNA sequence was isolated from Genespace of the SP80-3280 reference genome obtained of our group. The labeling of the regulatory region in sugarcane was carried out in two subsections: Core Promoter and Proximal Promoter. In the Core Promoter region we performed the identification of the TSS signal, the estimation of the size of the 5\' UTR region and the classification of the Core Promoter region in TATA-box or TATA-less. All processes were performed using the TSSPlant tool. The use of the TSSPlant tool motivated the development of a new tool to predict the TSS signal that we call TSSFinder. The TSSinder tool presented TSS signal prediction results superior to its peers, moreover this tool was successful in different organisms - Arabidopsis thaliana, Gallus gallus and Saccharomyces cerevisiae. In the Proximal Promoter region we performed the identification of TFBSs through two methodologies: de novo prediction and mapping of TFBS matrices (PSSM). The de novo prediction process was performed using two models: Expectancy Maximization and Gibbs Sampler and this process was performed only for subgroups of coexpressed genes or only for the set of homeologues sequences from each sugarcane gene. For the rest of the sequences only the mapping of the matrices of TFBSs identified during the de novo prediction process was conducted. In parallel all TFBSs identified in our work were compared with the TFBS database for plants. Through this procedure it was estimated which class of Transcription Factor is interacting with the TFBS identified in the Proximal Promoter region of the Scdr1, ScSuSy, ScPAL genes.With this work, we cover part of the gap observed in in silico studies for the regulatory region of sugarcane. In addition, we improved the process of identification the TSS signal for different organisms including dicotyledonous and monocotyledonous plants.
27

XCP : un environnement graphique conversationnel pour l'examen des structures d'un système , application à CP-67

Nguyen, Thanh Thi 06 June 1973 (has links) (PDF)
.
28

Analyse du transport solide en réseau d’assainissement unitaire par temps de pluie : exploitation de données acquises par les observatoires français en hydrologie urbaine / Analysis of solid transport in combined sewer network during wet weather : exploitation of data acquired by the French observatories in urban hydrology

Hannouche, Ali 23 November 2012 (has links)
Cette thèse valorise les données de mesure en continu de pluie de débit et de turbidité, ainsi que les bases de donnée de résultat d'analyse et les connaissances acquises dans le cadre des trois observatoires français en hydrologie urbaine, OPUR-Paris, OTHU-Lyon et ONEVU Nantes, pour valider et améliorer les connaissances sur les flux et les sources de particules vectrices de contaminants, en réseaux d'assainissement unitaire. Les données provenant de 6 sites expérimentaux drainés par un réseau d'assainissement unitaire ont été exploitées : Marais, Quais et Clichy à Paris, Cordon Bleu et Saint-Mihiel à Nantes et Écully à Lyon, avec sur chaque site des bases de données de longue durée qui ont permis des études statistiques sur des échantillons de plusieurs dizaines d'événements pluvieux et de journées de temps sec. Cette thèse a permis : 1- d'évaluer la représentativité de la turbidité pour analyser du transport solide en réseau ; 2- d'analyser et de modéliser statistiquement les concentrations et les masses de particules à l'échelle événementielle ; 3- d'étudier la dynamique des flux et des concentrations à l'échelle intra-événementielle. Les résultats obtenus indiquent d'une part, que la turbidité permet de décrire les dynamiques intra-événementielles des flux et des concentrations à condition d'exprimer ceux-ci sous forme relative, normalisée par les valeurs moyennes événementielles. En revanche, ces valeurs événementielles sont attachées par des erreurs systématiques non négligeables induites par les variations inter-événementielles de la relation MES-Turbidité (intervalle de confiance de l'ordre de 30% de la moyenne). Ils confirment d'autre part que la contribution des dépôts aux flux de temps de pluie est importante mais variable (entre 20 et 80% de la masse à l'exutoire selon l'événement), y compris sur un site réputé exempt de dépôts (grossiers). Autrement dit, les problématiques d'ensablement et de pollution de temps de pluie ne sont pas nécessairement liées. L'autre contribution majeure est celle des eaux usées « de temps sec ». De plus, ils nous ont permis de progresser dans la compréhension des phénomènes de décalage temporel entre hydrogramme et pollutogramme et d'effet piston / This thesis exploits continuous measurement of rainfall, discharge and turbidity data and the knowledge acquired by three French observatories in urban hydrology, OPUR-Paris, OTHU Lyon and ONEVU-Nantes, to validate and improve knowledge on suspended solids discharges and sources of particles, which are major vectors of contaminants in combined sewer systems. Data from six experimental sites served by a combined sewer system were used: Marais, Quais and Clichy in Paris, Cordon Bleu and Saint-Mihiel in Nantes and Ecully in Lyon. At each site, a long duration databases enabled statistical studies on samples of several tens of rainfall events and dry weather days. This thesis allowed: 1-to assess the representativeness of turbidity to analyze sediments transport in network; 2-to analyze and model concentrations and masses of particles at the scale of rain events; 3-to study the dynamics of fluxes and concentrations at intra-event scale. Results show that turbidity can describe the dynamics of intra-event fluxes and concentrations provided these are expressed in a relative form, normalized by the event mean values. However, these mean values are attached by significant systematic errors induced by variations of the inter-event TSS-turbidity relationship (95% confidence interval about 30% of average). The contribution of sewer deposits to wet weather suspended solids discharges is important but variable (between 20 and 80% of the mass at the outlet depending on the event), including for a site allegedly free of (coarse) sewer deposits. In other words, the problems of silting and contribution from deposits to wet weather pollution are not necessarily related. The other major contribution is from “dry weather” wastewater. In addition, they we made some progress in understanding the lag-time phenomena between hydrograph and pollutograph and the piston effect
29

Capacidade de RetenÃÃo de FÃsforo e Material Particulado em SuspensÃo por Manguezal de Ãrea Impactada por Efluentes da Carcinicultura. / Phosphorus retention capacity and Suspension of Particulate Matter in Mangrove Area impacted by effluents from Shrimp.

Louize Viveiro da Fonseca 21 April 2009 (has links)
As florestas de mangue estabilizam a zona costeira da erosÃo e atuam como zona tamponante entre o continente e o mar. Apresentam elevado grau de resiliÃncia e desempenham um importante papel no fluxo de energia e ciclo de nutrientes. SÃo influenciadas pelo crescimento da carcinicultura que pode causar sÃrios impactos ambientais, particularmente na regiÃo nordeste do Brasil devido à emissÃo de sÃlidos em suspensÃo e nutrientes para os estuÃrios. Avaliar a capacidade de retenÃÃo capaz de minimizar o impacto dos efluentes contendo elevados teores de fÃsforo e material particulado em suspensÃo e distinguir esta capacidade entre Ãreas de reconhecida contaminaÃÃo e Ãreas com caracterÃsticas naturais constituÃram o objetivo desta dissertaÃÃo. As coletas de Ãgua e sedimento ocorreram em 2 campanhas no rio Jaguaribe (impactado) e em 1 no rio Pacoti (natural) em marà sizÃgia durante 13 horas. Os parÃmetros pH, OD, %OD, temperatura, salinidade e condutividade foram medidos in situ com multisonda portÃtil. O MPS foi obtido por gravimetria (APHA, 2001). As fraÃÃes de fÃsforo na Ãgua e no sedimento foram determinadas segundo Grasshoff et al. (1999). A extraÃÃo de TP no sedimento seguiu Berner & Rao (1994). As medidas de fluxo foram calculadas segundo OVALLE et al (1990) e a estimativa do balanÃo de massa foi obtida de forma simplificada a partir do balanÃo entre os processos de entrada e saÃda de acordo com a mudanÃa de marÃ. Os parÃmetros hidroquÃmicos se mostraram semelhantes para as duas Ãreas de estudo, com exceÃÃo do OD, que alcanÃou valores sub-Ãxicos para a gamboa do Jaguaribe. O MPS variou entre 23,1 e 172,9 mg.L-1 para as duas campanhas na gamboa do Jaguaribe e entre 23,5 e 97,7 mg.L-1 para a gamboa do Pacoti, tendo sido considerados aceitÃvel quando comparado a outros trabalhos. As concentraÃÃes de fÃsforo para a gamboa do rio Jaguaribe variaram para o DPO4 entre 2,1 e 6,5 μM na gamboa do Jaguaribe, e 0,1 e 0,9 μM na gamboa do Pacoti; para o T-PO4 entre 3,2 e 15,9 μM para a gamboa do Jaguaribe e 2,9 a 7,3 μM para a gamboa do Pacoti; e para o Part-PO4, entre 1,3 e 11,9 μM para a gamboa do Jaguaribe e 2,8 a 7,7 μM para a gamboa do Pacoti; tendo o Jaguaribe apresentado maiores concentraÃÃes que o Pacoti em todas as campanhas e fraÃÃes, provavelmente relacionando o fÃsforo presente aos efluentes de carcinicultura. O fÃsforo no sedimento variou de 180,6 e 224,9 μg de P/g para o TP na gamboa do Jaguaribe e na gamboa do Pacoti foi de 117,5 μg de P/g, mostrando que as maiores concentraÃÃes de P no sedimento ocorreram na gamboa do Jaguaribe. Os fluxos de MPS (Flx MPS) variaram de 0 a 184,5 g.s-1, na primeira campanha na gamboa do Jaguaribe, 0 a 36,4 g.s-1, na gamboa do rio Pacoti e entre 0 e 836,5 g.s-1 na segunda campanha do Jaguaribe, onde, nesta, os valores foram quase uma ordem de grandeza maiores que na anterior e seu comportamento foi mais acentuado durante a marà vazante. O Flx D-PO4 na gamboa do rio Jaguaribe variou de 0 a 709 mg.s-1 e 0 a 9.113 mg.s- 1, enquanto que na gamboa do Pacoti variou de 0 a 13,4 mg.s-1. Para o Flx T-PO4, foi observada variaÃÃo de 0 a 1.248 mg.s-1 e de 0 a 11.065 mg.s-1 na gamboa do Jaguaribe, e de 0 a 295 mg.s-1 na gamboa do Pacoti, e o Flx Part-PO4 variou de 0 a 539 mg.s-1 e de 0 a 3.471 mg.s-1 para as campanhas do Jaguaribe, e de 0 a 281 mg.s-1 para a gamboa do Pacoti. O fluxo das fraÃÃes de P e do MPS estÃo estreitamente relacionados a velocidade da corrente. As estimativas de balanÃo de massa mostraram que o rio Jaguaribe retÃm tanto as fraÃÃes de fÃsforo quanto os teores de MPS, corroborando com a hipÃtese gerada por este trabalho. Entretanto, sua capacidade de suporte està diminuÃda em comparaÃÃo com os resultados de balanÃo encontrados para o rio Pacoti, que apresentou uma retenÃÃo de materiais bem mais significativa do que o rio Jaguaribe, caracterizando-o com uma grande capacidade de suporte. O rio Jaguaribe, por sua vez, provavelmente pode estar entrando em um processo de envelhecimento acelerado pela aÃÃo antrÃpica que causa impacto em suas Ãguas que esta diminuindo sua capacidade depuradora. / The mangrove forests stabilize the coastal erosion zone and act as a buffering between the continent and the sea. This forest presents high resilient degree, suggested to be used as marker of environmental changes. They play an important role in the energy flow and nutrients cycles. They are suffering with the growth of shrimp ponds. This tends to be responsible of causing serious environmental impacts, particularly in the northeast of Brazil and being associated with the emission of solids in suspension and nutrient in estuaries. The mangroves growth has a retention capacity capable to minimize the impact of the effluents that can be distinguished between areas being recognized contaminated and areas with natural characteristics, for that we were intended to test this capacity through the study of phosphorus and TSS mass balance in these estuaries. Sampling of water and sediment was in 2 campaigns: in the Jaguaribe creek (impacted) and in the Pacoti creek (natural) at tidal cycle. The parameters pH, OD, %OD, T, salinity and cond were measured in situ with portable multimode. TSS was obtained by gravimetric method (APHA, 2001). The fractions of phosphorus in water and in sediments were according to the Grasshoff et al. (1999). The TP extraction in sediment followed Berner & Rao (1994). The flow measures were calculated according to OVALLE et al (1990) and the estimate of the mass balance was obtained in simplified ways starting from the mass between the entrance processes to the agreement with the tide change. The hydrochemistry parameters showed the same for the two study areas, except for OD, that reached suboxic values for Jaguaribe creek. TSS varied between 23,1 and 172,9 mg.L-1 for two campaigns in the Jaguaribe creek and 23,5 and 97,7 mg.L-1 for the Pacoti creek, having been considered acceptable when compared the other works. The phosphate concentrations for Jaguaribe creek varied for D-PO4 between 2,1 and 6,5 μM in Jaguaribe creek, and 0,1 and 0,9 μM in Pacoti creek; for T-PO4 between 3,2 and 15,9 μM for Jaguaribe creek and 2,9 to 7,3 μM for Pacoti creek; and for Part-PO4, between 1,3 and 11,9 μM for Jaguaribe creek and 2,8 to 7,7 μM for Pacoti creek; tends Jaguaribe presented larger concentrations that Pacoti in all the campaigns and fractions, probably due to the effluents of shrimp pond. The phosphorus in the sediment varied from 180,6 to 224,9 μg of P/g for TP in Jaguaribe creek and in Pacoti creek it was of 117,5 μg of P/g, showing that the largest concentrations of P in the sediment happened in Jaguaribe. The flows of TSS (Flx TSS) varied from 0 to 184,5 g.s-1, in the first campaign in Jaguaribe creek, 0 to 36,4 g.s-1, in Pacoti creek and between 0 and 836,5 g.s-1 in the second campaign of Jaguaribe, where the values were almost an order of greatness larger than in the previous and your behavior was more accentuated during the ebb tide. Flx D-PO4 in Jaguaribe creek varied from 0 to 709 mg.s-1 and 0 to 9.113 mg.s-1, while in Pacoti creek it varied from 0 to 13,4 mg.s-1. To Flx T-PO4, variation was observed from 0 to 1.248 mg.s-1 and from 0 to 11.065 mg.s-1 in Jaguaribe creek, and from 0 to 295 mg.s-1 in Pacoti creek, and Flx Part-PO4 varied from 0 to 539 mg.s-1 and from 0 to 3.471 mg.s-1 for the campaigns of Jaguaribe, and from 0 to 281 mg.s-1 for Pacoti creek. The fluxes of the fractions of P and of TSS are much related with current speed. The estimates of mass balance showed that the river Jaguaribe retains the phosphorus fractions as much as the TSS, corroborating with the hypothesis generated by this work. However, their support capacity it is reduced in comparison with the balance results found for the river Pacoti that presented retention of materials much more significant than the creek in Jaguaribe River, characterizing him with a great support capacity. However, Jaguaribe River can probably be entering in an accelerated process of aging caused by the antrophic actions that impacts in its waters.
30

Adaptive Hierarchial RAID

Muppalaneni, Nitin 01 1900 (has links)
Redundant Arrays of Inexpensive Disks or RAID is a popular method of improving the reliability and performance of disk storage. Of various levels of RAID, mirrored or RAID1 and rotating parity or RAID5 configurations have become moat popular. Mirrored or RAID1 provides best overall performance and is easier to configure, but has 100 percent storage overhead for the redundancy. Rotating parity or RAID5, on the other hand, is quite inexpensive for the redundancy it provides, shorn impressive performance for reads and full-stripe writes in normal mode, but the small write performance is poor due to the read-modify-write cycle involved. The performance drops drastically when one of the disks fails and the system enters degraded mode. Also RAID5 is relatively difficult to configure. Typical non-scientific system disk access patterns exhibit very high locality of reference. This thesis presents the design and implementation of an Adaptive Hierarchical RAID array to exploit this high locality. Frequently accessed data is migrated towards the top of the hierarchy and not so frequently acee88ed data is moved down the hierarchy, thus adaptively rearranging itself to the access patterns. Previous work on Adaptive Hierarchical RAID such as HP AutoRAID has explored one part of the design space, namely design of configurable storage at the SGSI level with no interaction with higher level layers like volume manager. This thesis explores a different design point: namely, one that is centered at the volume manager layer. This is important also for the reason that with fibre channel disks and SCSI-3, Storage Area Networks (SAN) no longer need a conventional controller but a modified version of a controller that is more close to a volume manager.

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