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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.
1

Temperatura de superfície e evapotranspiração atual dos citros irrigados por diferentes sistemas / Surface temperature and actual evapotranspiration of citrus irrigated by different systems

Amendola, Emanoele Caroline 30 July 2018 (has links)
Submitted by Emanoele Caroline Amendola (emanoele.amendola@gmail.com) on 2019-01-30T22:41:52Z No. of bitstreams: 1 emanoele_amendola_final.pdf: 2500422 bytes, checksum: bdf6cd2de33e6676fc34811dd4f3c9f6 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2019-01-31T10:41:43Z (GMT) No. of bitstreams: 1 amendola_ec_me_ilha.pdf: 2500422 bytes, checksum: bdf6cd2de33e6676fc34811dd4f3c9f6 (MD5) / Made available in DSpace on 2019-01-31T10:41:43Z (GMT). No. of bitstreams: 1 amendola_ec_me_ilha.pdf: 2500422 bytes, checksum: bdf6cd2de33e6676fc34811dd4f3c9f6 (MD5) Previous issue date: 2018-07-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A citricultura brasileira exerce participação importante no mercado internacional agrícola. Atualmente o país é o maior exportador do suco destas frutas no mundo. A participação dos sistemas de irrigação na citricultura vem sendo cada vez mais acentuada, entretanto pesquisas com as aplicações do sensoriamento remoto, especialmente do algoritmo SAFER (Simple Algorith for Evapotranspiration Retrieving), e análises comparativas entre sistemas de irrigação em citros são escassas. Os objetivos deste trabalho foram detectar diferenças de temperatura de superfície entre os sistemas de irrigação (autopropelido, pivô central, microaspersão e gotejamento) e verificar a evapotranspiração atual de diferentes copas dos citros, utilizando o sensoriamento remoto, com o algoritmo SAFER, aplicado a fazendas comerciais cultivadas em diferentes idades - diferenciadas em adultas (plantas com 3 ou mais anos desde o plantio) e jovens (inferiores a 3 anos de plantio) - e tipos de copas de citros - laranjeiras, tangerineiras e limeira ácida Thaiti - no Noroeste Paulista. Após a aplicação da metodologia, foi verificada diferença significativa na temperatura de superfície dos pomares irrigados por diferentes sistemas de irrigação e encontrou-se uma copa com maior potencial para consumo de água entre os cítricos. / Brazilian citriculture has a significant stake in the international agricultural market. Currently the country is the biggest exporter of the juice in the world. The participation of irrigation systems in citriculture has been increasing steadily. However, research with the applications of remote sensing, especially the SAFER algorithm, and comparative analyzes between irrigation systems in citrus are scarce. The objective of this work was to detect differences in surface temperature between irrigation systems (self-propelled, center pivot, micro sprinkler and drip) and to verify the current evapotranspiration of different citrus canopies, using remote sensing with the SAFER algorithm applied to farms (plants with 3 years or more since planting) and young (less than 3 years of planting) - and citrus canopy types - orange, tangerine and Thaiti acid lime trees - in the Northwest region of São Paulo. After the application of the methodology, a significant difference in the surface temperature of orchards irrigated by different irrigation systems was verified, and a canopy with greater potential for water consumption among citrus was found. / CAPES: Código de Financiamento 001
2

Temperatura de superfície e evapotranspiração atual dos citros irrigados por diferentes sistemas /

Amendola, Emanoele Caroline. January 2018 (has links)
Orientador: Fernando Braz Tangerino Hernandez / Resumo: A citricultura brasileira exerce participação importante no mercado internacional agrícola. Atualmente o país é o maior exportador do suco destas frutas no mundo. A participação dos sistemas de irrigação na citricultura vem sendo cada vez mais acentuada, entretanto pesquisas com as aplicações do sensoriamento remoto, especialmente do algoritmo SAFER (Simple Algorith for Evapotranspiration Retrieving), e análises comparativas entre sistemas de irrigação em citros são escassas. Os objetivos deste trabalho foram detectar diferenças de temperatura de superfície entre os sistemas de irrigação (autopropelido, pivô central, microaspersão e gotejamento) e verificar a evapotranspiração atual de diferentes copas dos citros, utilizando o sensoriamento remoto, com o algoritmo SAFER, aplicado a fazendas comerciais cultivadas em diferentes idades - diferenciadas em adultas (plantas com 3 ou mais anos desde o plantio) e jovens (inferiores a 3 anos de plantio) - e tipos de copas de citros - laranjeiras, tangerineiras e limeira ácida Thaiti - no Noroeste Paulista. Após a aplicação da metodologia, foi verificada diferença significativa na temperatura de superfície dos pomares irrigados por diferentes sistemas de irrigação e encontrou-se uma copa com maior potencial para consumo de água entre os cítricos. / Abstract: Brazilian citriculture has a significant stake in the international agricultural market. Currently the country is the biggest exporter of the juice in the world. The participation of irrigation systems in citriculture has been increasing steadily. However, research with the applications of remote sensing, especially the SAFER algorithm, and comparative analyzes between irrigation systems in citrus are scarce. The objective of this work was to detect differences in surface temperature between irrigation systems (self-propelled, center pivot, micro sprinkler and drip) and to verify the current evapotranspiration of different citrus canopies, using remote sensing with the SAFER algorithm applied to farms (plants with 3 years or more since planting) and young (less than 3 years of planting) - and citrus canopy types - orange, tangerine and Thaiti acid lime trees - in the Northwest region of São Paulo. After the application of the methodology, a significant difference in the surface temperature of orchards irrigated by different irrigation systems was verified, and a canopy with greater potential for water consumption among citrus was found. / Mestre
3

Retenção de água da chuva na palha, solo e dossel vegetativo de milho e feijão / Rainfall retention in straw, plant and soil in corn and drybeans

Fontana, Vanessa Schwanke 17 December 2007 (has links)
The water is the most important factor and, at the same time, the more limitant than the plant needs for its development. Short periods of hidric stress can reduce crop productivity. In this way, the importance of knowing the rainfall amount that is retained in plant, straw and soil is fundamental to calculating the exact amount of water requested by the plant in their different growth stages. The objective of this work was to determine the water retention in the straw, in the soil and in the plants dossal after a precipitation, in the initial phase of growth of corn and bean crops. The drybeans (cv Rio Tibagi) and corn (hybrid Pioneer 30R53) were sowed in no-till (2, 4 and 6 t straw ha-1) and conventional (0 t of straw in covering) during 2006 agricultural year. The experimental design for corn was a bifatorial (2x4) and 3 replications, and for bean was a factorial and 3 replications. For corn two row spacings were tested (45 and 75 cm). Artificial rains were applied using a portable simulator of multiple nozzles, which applied 4 to 8 mm, with 30 mm h-1 rain intensity. They were made ridges in the area, (with steepness to drain the water) and a plastic canvas covered the soil surface, so that water that arrived to the plastic drained for the surface until a collector placed among two plants rows. Straw rugs were made with different amounts of straw (0, 2, 4 and 6 t ha-1) and put among the plants rows above soil surface (plastic canvas). The determination of the amount of water retained was made through the differences of weightings. The amount of applied water with the simulator was known using pluviometers; the straw rugs were weighed before and after rain simulation (for difference, it was obtained the value of water retention in straw). The water that passed through straw and was drained until the plastic was collected after the rain, in the collector placed between the plants lines and measured with a test tube, and obtained the amount of water that arrived to the soil, that in practice corresponds to the water that infiltrates in the soil. For difference, was obtained the water that was retained in the dossal. Statistical analysis the variance analysis, with regression in level of 5%. Water retention in the initial phase of corn was larger in the soil, for all straw amounts, and, in the final phase, water retention in plants dossal was increased. The largest water retention in straw was with 6 t ha-1, being the largest retention in the spacing of 45 cm among rows. In the dossal, the retention was smaller in the beginning and larger at the end, with the plants development (larger leaf area index). In the soil, water retention was larger where there was less straw in the initial phase. The retention was larger where there was more straw covering and in the smallest spacing (45 cm), being the soil retention larger without covering and with 75 cm among lines. In the dossal, retention was larger in the spacing 45 cm. In the black bean, water retention in straw was larger in the initial phase and with larger amount of straw, and in soil the largest water retention happened without covering (7,4mm). In the plants dossal water retention increased according to crop development. / A água é o fator mais importante e, ao mesmo tempo, o mais limitante que a planta necessita para o seu desenvolvimento. Curtos períodos de deficiência hídrica podem reduzir a produtividade das culturas. Assim, a importância de saber a quantidade de água que fica retida na planta, na palha e no solo é fundamental na hora de calcular a quantidade exata de água requerida pela planta nos seus diferentes estágios de crescimento. O objetivo deste trabalho foi determinar a retenção de água no solo, na palha e no dossel de plantas após uma precipitação, na fase inicial de crescimento das culturas do milho e feijão. O feijão (cv Rio Tibagi) e o milho (híbrido Pioneer 30R53) foram semeados no sistema plantio direto (2, 4 e 6 t palha ha-1) e convencional (0 t de palha em cobertura) durante o ano agrícola de 2006. O delineamento experimental para o milho foi um bifatorial (2 x 4) e três repetições, e o do feijão foi um fatorial com três repetições. No milho foram testados dois espaçamentos entre linhas (45 e 75 cm). As chuvas artificiais foram aplicadas utilizando-se um simulador estacionário de bicos múltiplos e oscilantes, o qual aplicou de 4 a 8 mm, numa intensidade de 30 mm h-1. Foram feitos camalhões na área, (com declividade para dar escoamento a água) e na superfície do solo foi colocada uma lona plástica para que a água escoasse pela superfície do solo até um coletor colocado entre duas linhas de plantas. Foram confeccionados tapetes de palha com diferentes quantidades de palha (0, 2, 4 e 6 t ha-1) e colocados entre as linhas de plantas acima da superfície do solo (lona plástica). A determinação da quantidade de água retida foi feita através das diferenças de pesagens. A quantidade de água aplicada pelo simulador era conhecida através de pluviômetros; os tapetes de palha eram pesados antes de serem colocados entre as linhas de plantas e após a chuva simulada (por diferença, era obtido o valor da água retida na palha); a água que passava pela palha e escoava até o plástico era coletada após a chuva no coletor colocado entre as linhas de plantas e medida com proveta, e, assim obtido o valor da quantidade de água que chegava ao solo, que na prática corresponde a água que infiltra no solo. Por diferença foi calculada a água que ficou retida no dossel. Foi realizada análise da variância, com regressão em nível de 5%. A retenção de água na fase inicial da cultura do milho foi maior no solo, para todas as quantidades de palha, e, na fase final aumentou a retenção no dossel de plantas. A maior retenção de água na palha foi na quantidade de 6 t ha-1, sendo a maior retenção no espaçamento de 45 cm entre linhas. No dossel, a retenção foi menor no início e maior no final, com o desenvolvimento da mesma (maior Índice de área foliar). No solo, a retenção foi maior onde havia menos palha na fase inicial. A retenção foi maior onde havia mais palha na cobertura e no menor espaçamento (45 cm), sendo a retenção no solo maior onde não havia cobertura e a 75 cm entre linhas. No dossel, a retenção foi maior no espaçamento 45 cm, com menor quantidade de palha em cobertura. No feijão, a retenção na palha foi maior na fase inicial e com maior quantidade de palha em cobertura, sendo que no solo a maior quantidade de água chegou onde não havia cobertura. No dossel de plantas a retenção de água foi aumentando conforme o desenvolvimento da cultura.
4

Effects of Solids Loadings and Particle Size Distribution on Siphon Ceramic Candle Filters

Renzi, Danielle 01 January 2011 (has links)
In the rural areas of Madagascar only 29% of the population has access to clean water and 10% has access to improved sanitation. It has been estimated that environmental risk factors, such as inadequate access to clean drinking water and proper sanitation, are responsible for 94% of the diarrheal disease burden. This study was focused on testing a point-of-use technology called the Tulip filter, which is a siphon ceramic candle filter impregnated with silver. The purpose is to assess its feasibility for implementation in rural regions of Madagascar through a laboratory study performed at the University of South Florida. The study tested the Tulip filters for turbidity, total coliform, and E. coli removal for various types of water. Each filter processed synthetic water classified as control (tap water, <1 >NTU), low turbidity (5-7 NTU), medium turbidity (25-35 NTU), or high turbidity (60-80 NTU). Approximately once every 100 L the filters processed pond water to test coliform removal. Furthermore, the pthesis size distribution was measured to analyze the effectiveness of filter to remove various pthesis sizes. Two of the seven Tulip filters tested had some quality control issues with the glue connecting the ceramic candle to the plastic cap and failed at 350 L. Of the functioning filters, the turbidity removal ranged from 93% to 98% with none of the 779 samples taken from 4 filters above the WHO recommended 5 NTU for drinking water. The log removal of total coliforms was about 3.90 to 4.16 and achieved an average of 1 CFU/100mL of E. coli in the filtered water. WHO guidelines consider water with 1-10 CFU/100 mL a "low risk" and all but one of the working filters had E. coli and total coliform concentrations within, or below, this range for all samples (n=20 for each filter). The filters also showed an average of 96% removal of pthesiss of all size ranging from 0.5 to 10 µm. This study finds that the Tulip filter is an appropriate of point-of-use technology that enables rural areas access to "low risk" water, at a low cost and with minimal maintenance. This study also reinforces the importance of adding silver or another biocide to ceramic filters because pthesiss of sizes up to 10 µm are able to pass through the filter. This is particularly a problem because pathogens can range from 0.01 µm to 100 µm.
5

Hållbar Vattenanvändning : Tillgodoseende av behov av vatten för bevattning och fyllande av pooler / Sustainable water usage :  A sustainable supply of water need for irrigation and fillage of pools

Hård af Segerstad, Ebba, Odenlind, David January 2021 (has links)
I norra Storstockholm produceras och distribueras dricksvatten av kommunalförbundet Norrvatten. Under värmeböljan sommaren år 2018 ökade dricksvattenförbrukningen bland medlemskommunerna till en sådan hög nivå att Norrvattens tillgängliga kapacitet för dricksvattenproduktion riskerade att inte räcka till. En bidragande orsak till detta, antogs vara att en stor del av den ökade vattenförbrukningen gick till bevattning och fyllande av pooler. Det är ett behov som Norrvattens verksamhet inte är dimensionerad för att hantera. I takt med dagens växande befolkning i Norrvattens medlemskommuner och en hotande global uppvärmning, förväntas risken för kapacitetsbrist tillta. Således var syftet med detta arbete att studera hur behov av vatten för bevattning och fyllande av pooler kan tillgodoses på ett långsiktigt hållbart sätt bland Norrvattens medlemskommuner utifrån de tre hållbarhetsdimensionerna. Med hjälp av litteraturstudier, intervjuer och beräkningsmodeller identifierades alternativa lösningar och effektiviseringsmöjligheter gällande tillgodoseendet av vattenbehov för bevattning och poolfyllning. Dessutom genomfördes en stickprovsundersökning med syftet att studera socioekonomiska faktorer, vid eventuell implementering av de identifierade alternativa lösningarna och effektiviseringsmöjligheterna i Norrvattens medlemskommuner. Därefter applicerades en kvantitativ analys på det erhållna dataunderlaget med väldefinierade statistiska metoder för konfidensintervall och hypotesprövningar på signifikansnivån 5 %. Resultatet visade flertalet alternativa lösningar och effektiviseringsmöjligheter var passande att implementera för att tillgodose behov av vatten för bevattning och fyllande av pooler bland Norrvattens medlemskommuner. Det berodde på en stor välvilja gentemot såväl miljön som Norrvattens verksamhet. Mer konkret identifierades en utbredd vilja att förändra konsumtionsbeteenden gällande vattenanvändning för bevattning och fyllande av pooler. Som en följd fanns också en villighet att betala mindre summor för alternativa lösningar och effektiviseringsmöjligheter för att tillgodose sådana vattenbehov. Dock påvisades även en utbredd motvillighet till kraftiga ökningar i priser och kostnader för knippade med vattentjänster, varpå mer kostsamma alternativa lösningar uteslöts som långsiktigt hållbara utifrån socioekonomiska hållbarhetsperspektiv. Därmed rekommenderades Norrvatten att fortsätta planera för utbyggnation av sin produktionskapacitet, eftersom de identifierade alternativa lösningarna och effektiviseringsmöjligheterna inte ansågs tillräckliga för att nollställa behov av dricksvatten producerat av Norrvatten för bevattning och fyllande av pooler. Samtidigt drogs slutsatsen att behovet av utbyggd kapacitet skulle kunna reduceras vid implementering av de identifierade lösningarna och effektiviseringsmöjligheterna. Dock kunde inte det reducerade behovet beskrivas i kvantitativa termer med den applicerade arbetsmetodiken. Således rekommenderades Norrvatten att i framtiden arbeten genomföra en kartläggning av detta, i syfte att erhålla värdefullt beslutsunderlag kring storlek på utbyggd produktionskapacitet. / In the northern part of Greater Stockholm, drinking water is produced and distributed by the municipal association Norrvatten. During the height of the summer 2018, drinking water consumption among the member municipalities increased to such an extent that the available production capacity was nearly insufficient. This was assumed to be due to major increases in drinking water consumption for garden irrigation and filling of pools, which are water needs that the production capacity is not dimensioned to handle. Furthermore, the risk of production capacity shortage is assumed to increase in the near future due to population growth and global warming. The purpose of this thesis was to examine possible approaches to supply the need for water for garden irrigation and filling of pools among the member municipalities of Norrvatten in a long-term sustainable manner with regard to the three sustainable dimensions. Based on literature studies, interviews and theoretical models, alternative solutions and efficiency opportunities of supplying water needs for garden irrigation and filling of pools was identified. A sample survey was also conducted with the aim of studying socio-economic factors regarding a potential implementation of the identified alternative solutions and efficiency opportunities among the member municipalities. Subsequently, quantitative analysis was applied to the obtained data with well-defined statistical methods for confidence intervals and hypothesis tests at the significancelevel of 5 %. The result illustrated implementable alternative solutions and efficiency opportunities of supplyingwater needs for garden irrigation and filling of pools. It was due to a large benevolence towards the environment and Norrvatten’s operations. More specifically, a widespread willingness to change consumption behaviours regarding water utilization for garden irrigation and filling of pools was identified. As a consequence, there was also a great willingness to pay smaller sums for alternative solutions and efficiency opportunities of supplying such water needs. However, a widespread reluctance to larger costs associated with water services was also identified, whereby costly alternative solutions were excluded as long-term sustainable from a socio-economic perspective. Due to this, Norrvatten was recommended to continue planning for an expansion of its production capacity, with regard to the conclusion that the identified alternative solutions and efficiency opportunities were not considered sufficient to completely reduce the need for drinking water produced by Norrvatten for garden irrigation and filling of pools. Nevertheless, it was also concluded that the need for expanded capacity could be reduced when implementing the identified solutions and efficiency opportunities. However, the reduced need could not be described in quantitative terms with the chosen methodology. Because of that reason, Norrvatten was recommended to examine this further in future projects considering that it would provide a valuable basis for operation decisions regarding expanded production capacity.
6

From the scamander to syracuse: studies in ancient logistics

Barker, Peter Frederick 31 October 2005 (has links)
This dissertation discusses logistical aspects of the Persians invasion of Greece; the Athenian need for timber for building warships; supply problems in their assault on Syracuse; and the march of Alexander's army from Macedonia into Asia. The amount of cereals needed by the Persian and Greek armies and navies is calculated from modern nutritional data and an estimate of the numbers of combatants. The location and size of the Persian food dumps; the excavation of the Athos canal; and the ships and materials needed to build the bridges of boats are considered. The Athenian need for ship-timber led to the costly occupation of Amphipolis. An assured supply of cereals was one motive for the disastrous Sicilian Expedition. The Athenian fleet was an inefficient long-range support for an army which had to protect its non-combatant sailors. This was realised by Alexander the Great, who crossed the Hellespont without naval support. / Classics and Modern European Languages / M.A. (Classics)
7

From the scamander to syracuse: studies in ancient logistics

Barker, Peter Frederick 31 October 2005 (has links)
This dissertation discusses logistical aspects of the Persians invasion of Greece; the Athenian need for timber for building warships; supply problems in their assault on Syracuse; and the march of Alexander's army from Macedonia into Asia. The amount of cereals needed by the Persian and Greek armies and navies is calculated from modern nutritional data and an estimate of the numbers of combatants. The location and size of the Persian food dumps; the excavation of the Athos canal; and the ships and materials needed to build the bridges of boats are considered. The Athenian need for ship-timber led to the costly occupation of Amphipolis. An assured supply of cereals was one motive for the disastrous Sicilian Expedition. The Athenian fleet was an inefficient long-range support for an army which had to protect its non-combatant sailors. This was realised by Alexander the Great, who crossed the Hellespont without naval support. / Classics and Modern European Languages / M.A. (Classics)

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