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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.
11

Une innovation technique en train de se faire. Le goutte à goutte en pratique au Maroc : acteurs, bricolages et efficiences. / Technical innovation in the making Drip irrigation in use in Morocco : actors, bricolages and efficiencies.

Benouniche, Maya 22 December 2014 (has links)
Promue comme la technique d'irrigation en théorie la plus efficiente, et mise à contribution pour régler les grandes crises d'eau, le goutte à goutte se diffuse très rapidement de par le monde. La perspective d'une technique étudiée en station expérimentale, sans utilisateurs, et en définitive idéalisée, nous a d'emblée interpellé. Rejetant une vision normative du goutte à goutte (ce qu'il devrait être/faire), nous l'avons étudié en pratique, en interactions avec une multitude d'acteurs (ce qu'est le goutte à goutte et ce qu'il fait et pour qui). Notre objectif est d'analyser comment la pratique de cette innovation technique a changé la technologie et les trajectoires socioprofessionnelles des acteurs, et l'impact sur les efficiences d'irrigation. Nous montrons comment les acteurs locaux ont pris le contrôle de l'innovation, et des responsabilités dans des domaines que l'on pensait réservés aux ingénieurs dans la production, l'utilisation et la diffusion de l'innovation. Ces initiatives locales croisent et renforcent les programmes étatiques de développement du goutte à goutte. La technologie a séduit un grand nombre d'acteurs non-conventionnels qui ont changé la technologie, mais ont changé aussi eux-mêmes. La diffusion réussie du goutte à goutte assure leur promotion socioprofessionnelle, et à leur tour ils vont attirer d'autres utilisateurs dans le monde du goutte à goutte. C'est là où se résume la force du goutte à goutte comme objet technique autour duquel de puissants réseaux sociotechniques se sont construits. Le bricolage a permis la conception de systèmes plus adaptés aux conditions locales, mais aussi un apprentissage de la technique pour apprivoiser le changement. D'une technologie importée accessible à une minorité de grands agriculteurs, une pluralité de systèmes de goutte à goutte de proximité sont désormais accessibles au plus grand nombre. Enfin, les performances d'irrigation de ces systèmes sont hétérogènes, certains agriculteurs irriguant 3-4 fois plus que les volumes nécessaires aux besoins de la culture. Ces performances peuvent être expliquées par des pratiques d'irrigation favorisant le confort hydrique de la plante, traduisant ainsi les logiques des acteurs. Aujourd'hui, « l'économie d'eau » est un objectif irréalisable, qui n'est prioritaire pour aucun des acteurs, y compris l'Etat-promoteur. Nous concluons qu'il serait intéressant de mobiliser les acteurs non-conventionnels pour en faire des alliés pour intégrer le concept d'économie d'eau sur le terrain auprès des utilisateurs. / Abstract Promoted as the most efficient irrigation technology, able to contribute to solving the major current water crises, drip irrigation spreads quickly throughout the world. The perspective of an idealized technology with a theoretical efficiency studied in experimental stations without users struck us immediately. Rejecting a normative view of drip irrigation (what it should be/do), we studied it in practice, interacting with a multitude of actors focusing on what it does and for whom. Our objective is to analyse how the practice of this technical innovation has changed the technology and the socio-professional pathways of different actors involved in drip irrigation, and analyse the impact on actual irrigation efficiencies. We show how local actors took control of the innovation taking responsibility in spheres once thought reserved for engineers in the production, use and dissemination of innovation. These local initiatives crossed and strengthened state development programs promoting drip irrigation. The technology attracted a large number of non-conventional actors who changed the technology, but also changed themselves. The successful diffusion of drip irrigation ensures their socio-professional promotion, and they in turn will attract more users to the world of drip irrigation. This constitutes the strength of drip irrigation, which is a technical object around which powerful socio-technical networks were built. Bricolage helped design systems better suited to local conditions, but was also a learning process to incorporate change. From an imported technology accessible to a minority of large farmers, a plurality of drip systems is now accessible for a wide diversity of farmers. Finally, the performance of irrigation systems is heterogeneous, some farmers irrigating 3-4 times the volume necessary for crop water requirements. This performance can be explained by irrigation practices favouring a water comfort to crops, reflecting the logic of the actors. Today, "water saving" is an unattainable goal, as it is not a priority for any of the actors, including the state. We conclude that it would be interesting to engage non-conventional actors as allies in order to promote the concept of water saving on the field with users.
12

Automação como suporte ao manejo sustentado da irrigação na cultura da alface no no município de Itabaiana - SE

Giacomelli, Waldiney 31 March 2011 (has links)
The present work was developed in the experimental area of the project "Pequeno Produtor, Grande Empreendedor that it is an area of vegetables production. It is located in the municipal district of Itabaiana in the state of Sergipe. The objective was to project and to create an automatized control of an irrigation system by leak, verifying the productive aspects related to the sustainability indicators. The calculation for water replacement in the soil was based on the estimate of the evapotranspiration starting from the reading of the climatological greatness accomplished by the agriculture-meteorological station installed at the experiment place. The equation of Penman-Montheith was used, recommended by the Food and Agricultural Organization of the United Nations (FAO). Once the estimated evapotranspiration was known, the control system did the other calculations to establish the time for the replacement of the necessary water sheet. The final comparison between the experiment and the normal production used by the producer points to a significant profit in the consumption of water and electric power. The microcontrolled control besides contributing for the decrease of the consumption of water supplies and electric power also provided an economy in the maintenance of the installed equipments. Doing so, a possibility of a higher economical profit is presented, contributing for life improvement of the small family producers, making their social and economic indicators better. / O presente trabalho foi desenvolvido na área experimental do projeto Pequeno Produtor Grande Empreendedor que é uma área de produção de hortaliças. Fica localizada no município de Itabaiana no estado de Sergipe. O objetivo foi projetar e criar um controle automatizado de um sistema de irrigação por gotejamento, verificando os aspectos produtivos relacionados com os indicadores de sustentabilidade. O cálculo para a reposição de água no solo foi baseado na estimativa da evapotranspiração a partir da leitura das grandezas climatológicas realizadas pela estação agro-meteorológica instalada no local do experimento. Utilizou-se a equação de Penman-Montheith, considerada padrão desde 1998 e recomendada pela Food and Agricultural Organization of the United Nations (FAO). Conhecida a evapotranspiração estimada, o sistema de controle realizou os demais cálculos para estabelecer o tempo necessário para a reposição da lâmina de água necessária. A comparação final entre o experimento e a produção normal utilizada pelo produtor aponta um ganho significativo no consumo de água e de energia elétrica. O controle microcontrolado além de contribuir para a diminuição do consumo dos recursos hídricos e energia elétrica, também proporcionou uma economia na manutenção dos equipamentos instalados. Com isso, chega-se a apresentar uma possibilidade de ganho econômico maior contribuindo para a melhoria de vida dos pequenos produtores familiares melhorando seus indicadores sócio-econômicos.
13

Zdravotně technické instalace provozní a výrobní budovy / Plumbing Systems for Factory Building

Nesvadbová, Petra January 2012 (has links)
Administrative building with changing rooms and washrooms facilities for associated industrial production in the faktory building. Use rainwater for flushing. Solution separated sewers. Rainwater brought into the retention tank where it is collected for flushing, excess rain water seeps through theblocks generated drainage system in the basement. Investigation using water-efficient fixtures and equipment. Designed saving shower heads, batteries, toilet tanks and efficient operation of the urinals.
14

Lösningar för regnvattenskörd för enbostadshus i Brikama / Rainwater harvesting solution for single residential houses in Brikama

Nyassi, Sereh January 2023 (has links)
Gambia is the smallest country on the African mainland, surrounded by Senegal on all it's borders except the coastal one. Gambia faces a pressing issue with water supply shortages, along with more than one third of the world’s population. The aim of this study is to propose a system that will solve water supply shortage through a local water supply system. The method mainly consisted of a literature review, aimed to provide an overview of the subject as well as to highlight existing gaps within today’s research about rainwater harvesting systems. Furthermore, a case study was used to determine the best way to design the rainwater harvesting system. The results of the study are showcased through a tank and pipe system, where water is collected on the roof of the residential homes and stored in a polyethylene tank on the ground. The results from the survey, asking questions related to the inhabitants’ water usage habits, were analyzed and represented through a table. In Brikama rainwater can be used for laundry, cooking and watering plants. The positive effects it brings include, but are not limited to, reduction of soil erosion, restoring the ground water cycle, as well as making people become more self-sufficient. In this study, a system for Brikama can be optimized by using Solvatten technology in combination with conventional rainwater harvesting methods. The tank volume suggested by Mun and Han (2011) is a feasible premiss, however it can not be directly applied to Gambian rainwater conditions as there are differing presumptions between the reference country Korea, and Gambia. Additionally, the validity of the study is affected as the reference studies suggest using computer simulations, as well as computer models as a basis for the operational and input data. / Gambia är det minsta landet på det afrikanska fastlandet, omgivet av Senegal på alla dess gränser utom den kustnära. Gambia står inför ett akut problem med vattenbrist, tillsammans med mer än en tredjedel av världens befolkning. Syftet med denna studie är att föreslå ett system som löser problematiken med vattenförsörjning genom ett lokalt vattenförsörjningssystem. Metoden bestod huvudsakligen av en litteraturöversikt, som syftade till att ge en överblick över ämnet samt att lyfta fram befintliga luckor inom dagens forskning om system för uppsamling av regnvatten. Dessutom användes en fallstudie för att bestämma det bästa sättet att designa systemet för uppsamling av regnvatten. Resultatet av studien visas genom ett tank- och rörsystem, där vatten samlas upp på taket av bostadshusen och lagras i en polyetentank på marken. Resultatet från undersökningen, med frågor relaterade till invånarnas vattenanvändningsvanor, analyserades och representerades genom en tabell. I Brikama kan regnvatten användas för tvätt, matlagning och vattning av växter. De positiva effekter det medför inkluderar, men är inte begränsade till, minskning av jorderosion, återställande av grundvattnets kretslopp, samt att få människor att bli mer självförsörjande. I denna studie kan ett system för Brikama optimeras genom att använda Solvatten-teknik i kombination med konventionella metoder för uppsamling av regnvatten. Tankvolymen som föreslagits av Mun och Han (2011) är en genomförbar premiss, men den kan inte tillämpas direkt på gambiska regnvattenförhållanden eftersom det finns olika antaganden mellan referenslandet Korea och Gambia. Dessutom påverkas studiens validitet eftersom referensstudierna föreslår att man använder datorsimuleringar, samt datormodeller som underlag för drift- och indata.
15

<b>SUPPLEMENTAL IRRIGATION PROGRAM EFFECTS ON VARIOUS LAWN GRASSES IN THE COOL-HUMID ZONE</b>

Antonio Verzotto (18429612) 23 April 2024 (has links)
<p dir="ltr">Water scarcity and acute drought continue to be serious concerns, even in humid climates where precipitation normally exceeds evapotranspiration (ET), highlighting the need for improved landscape water conservation practices. Lawns represent the largest area in most managed landscapes and require regular mowing, feeding and sometimes supplemental summer irrigation to persist. A general historical guideline for lawn irrigation is to supply 25-38 mm per growing wk-1 in the absence of rainfall. This fixed volume is often applied on a programmatic “set and forget” three times per week schedule (e.g. M-W-F). This application guideline often results in excess irrigation as it does not take into account plant need or prevailing environmental conditions. Further, in times of acute summer drought policymakers may restrict irrigation to once or twice weekly to conserve water. The effects of these regulations on turf health and potential water savings are unclear. Thus, two multi-year summer field studies were conducted to identify opportunities for improved lawn water conservation. Study one evaluated the effect of varying weekly irrigation volume and frequency on mature Kentucky bluegrass (Poa pratensis L.:KBG) located under a fixed-roof rainout structure. Turfgrass response was measured as visual turf quality (TQ), digital green color (DGC), volumetric soil water content (VWC) and area under the curve for each response variable. In year one, KBG was subject to six irrigation programs and compared to a high deficit control for 49 days. The programs were: 25 mm total water wk-1 applied either three times (M-W-F) or twice (M and F) weekly, 19 mm total wk-1 twice weekly (M and F), 13 mm total wk-1 once weekly and 60 or 80% accumulated ETo three times weekly. Due to poor performance, the high deficit control and 60% ETo were excluded from further evaluation. In year two, seven programs were evaluated: 33 mm total water wk-1 applied once, twice, or three times weekly, or every-other-day, 25 mm total wk-1 applied twice or three times weekly and 80% ETo twice weekly for 63 days. In both years, generally, 25-33 mm wk-1 applied two or three times wk-1 produced the most consistent TQ, DGC and highest VWC. Study two compared three supplemental irrigation programs to a natural rainfall control for six widely planted cool-season lawn grasses for 70 days. The six lawn grasses were: a KBG sod, seeded drought tolerant and susceptible KBG cultivars, a turf-type tall fescue (Schedonorus arundinaceus (Schreb.) Durmort.: TTTF) blend and two KBG and perennial ryegrass (Lolium perenne L.:PRG) mixtures. In Study two, highly significant differences p < .001 occurred for irrigation program and lawn grasses. While supplemental irrigation aided all grasses, rainfall in year one and two measured 119 mm and 343 mm, respectively, affecting data in each study year. Area under the turfgrass quality curve (AUTQC) was lowest for the rainfall control (339 and 425) and highest for 33 mm wk-1 applied three times (507 and 526) and 80% ETo programs (508 and 535) in year one and two, respectively. Annual responses for DGC and VWC generally followed TQ trends. For grasses subject only to natural rainfall, TTTF, and the KBGs were generally superior to the KBG:PRG mixtures, thus emphasizing the importance of species selection. In summary, these studies compared a traditional “set and forget” irrigation program to a range of alternative programs and different lawn grasses. These data provide evidence for irrigation savings by employing a combination of planting drought tolerant lawn species and adopting a more limited irrigation program. Future field studies should include the evaluation of adaptive, data-driven programs based on forecast environmental conditions and threshold responses like DGC or predetermined VWC set points calibrated for varying soil types and growing environments.</p>
16

Basin-scale change in water availability and water quality under intensified irrigated agriculture

Törnqvist, Rebecka January 2013 (has links)
Changes in land use and water use can greatly impact the cycling of water and water-borne substances. Increased redistribution of river water to irrigated fields can cause enhanced evapotranspiration and decreased river discharge. Additionally, the water quality can be affected by the external input of fertilisers and pesticides, and by changed pollutant transport pathways in expansive irrigation canal systems. This thesis examines basin-scale changes in water use, river discharge, water quality and nitrogen (N) loading under conditions of intensified irrigated agriculture, using the Aral Sea drainage basin (ASDB) with its two large rivers Syr Darya and Amu Darya in Central Asia as study area. Results show that more efficient irrigation techniques could reduce outtake of river water to the cotton fields in the ASDB by about 10 km3/year, while the corresponding river water saving at the outlet would be 60% lower. The result illustrates the importance of accounting for return flows of irrigation water in basin-scale water saving assessments. Moreover, a decrease in riverine N concentrations at the outlet of the Amu Darya River Basin (ADRB) was observed during a 40-year period of increasing N fertiliser input. The decrease was identified to be primarily caused by increased recirculation of river water in the irrigation system, leading to increased flow-path lengths and enhanced N attenuation. Decreasing N loads were shown to be primarily related to reduced discharge. N export from the basin may further decrease due to projected discharge reductions related to climate change. Furthermore, nutrients and metals were occasionally found at concentrations above drinking water guideline values in surface waters in the ADRB. However, metal concentrations in groundwater in the lower ADRB were subject to orders of magnitude higher health hazards. Projected decrease in downstream surface water availability would thus imply decreased access to water suitable for drinking. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Submitted. Paper 5: Manuscript.</p>
17

Implantação de um programa de uso racional de água na universidade federal de goiás estudo de caso edifício da reitoria / Proposal for implementation of the ongoing program of water conservation at Federal University of Goias- Case Study of the rectory building

GOMES, Marcelus Isaac Lemos 01 September 2011 (has links)
Made available in DSpace on 2014-07-29T15:01:46Z (GMT). No. of bitstreams: 1 DISSERTACAO-07122011.pdf: 2360307 bytes, checksum: 56a7b9d04ed9b12f456d662b2d4e6cb4 (MD5) Previous issue date: 2011-09-01 / The water scarcity has led to changes in position of economic environmental and political issues besides trying to seek new sources of water located at further distances in places more distant. That is to reduce the amount of water needed by, urban population without compromising the quality of activities. This work had the objective to establish a water conservation program, initiated by the implementation of programs for the Rational Use of Water in the building of the Rectory of the Federal University of Goiás, in the city of Goiania. The building selected for the development of a Case Study is used for administrative activities. It comprises two floors, with total built up area of 2,013.84 m2, which was chosen because it showed characteristics that allowed the installation of water meter, for monitoring the daily consumption, and the registration of all points of water consumption, as well as the classification of user categories (including fixed and transitory people). The methodology used considered initially an evaluation and a diagnostic of the building selected for the study. In the sequence a plan was developed and the proposed actions to help in the reduction in water usage was later implemented. Finally, the management of the actions to keep rational usage of water took place including daily monitoring. Based on the analysis of the collected data an economic analysis was carry out to quantify the economic benefits achieved. The consumption data were collected over a period of 240 days, including 120 days before and 120 days after the implementation of water saving measures. The collected data allowed an analysis of the potential for reducing the monthly consumption of water, which in this case was around 30%. The economic analysis showed that the amount invested, including equipment and manpower, would be paid in approximately 20 months, considering average rate of the capital return equal to 0.75% per month. / A escassez da água levou a mudança de postura nos ambientes econômicos, ambientais e políticos, não tratando apenas de buscar novas fontes de água em locais cada vez mais distantes. Trata-se de reduzir a quantidade de água necessária pelas populações, mas sem comprometer a qualidade das atividades desenvolvidas. O presente estudo teve com objetivo a implantação de um programa de conservação da água, iniciado pela implementação de Programas de Uso Racional da Água no prédio da Reitoria da Universidade Federal de Goiás, em Goiânia. A edificação escolhida para o desenvolvimento de um caso de estudo, é utilizada para atividades administrativas, é constituída por dois pavimentos com área total construída de 2.013,84 m2, sendo apropriada para o estudo por apresentar características que permitiram a instalação de hidrômetro, para o monitoramento do consumo diário, e o cadastramento de todos os pontos de consumo de água, bem como a classificação dos tipos de usuários (fixos e flutuantes). A metodologia utilizada contemplou inicialmente uma avaliação e diagnostico da edificação escolhida. Em seguida foi elaborado um plano e posteriormente implantadas medidas que auxiliaram a redução do consumo. Finalmente foi realizado o gerenciamento das ações visando à manutenção da redução alcançada, que incluiu o monitoramento diário. Com base nos dados obtidos foi realizada uma analise econômica para quantificar os benefícios financeiros alcançados. Os dados de consumo foram coletados durante um período de 240 dias, sendo 120 antes e 120 dias após a implantação das medidas economizadoras de água. Os dados coletados permitiram uma análise do potencial de redução do consumo mensal de água, que neste caso foi da ordem de 30%. A análise econômica mostrou que o valor investido, incluindo equipamentos e mão-de-obra, seriam pagos em aproximadamente 20 meses, considerando uma taxa media de remuneração do capital de 0,75% ao mês.
18

Rice yields under water-saving irrigation management : A meta-analysis

Åberg, Amanda January 2017 (has links)
Water scarcity combined with an increasing world population is creating pressure to develop new methods for producing food using less water. Rice is a staple crop with a very high water demand. This study examined the success in maintaining yields under water-saving irrigation management, including alternate wetting and drying (AWD). A meta-analysis was conducted examining yields under various types of water-saving irrigation compared to control plots kept under continuous flooding. The results indicated that yields can indeed be maintained under AWD as long as the field water level during the dry cycles is not allowed to drop below -15 cm, or the soil water potential is not allowed to drop below -10 kPa. Yields can likewise be maintained using irrigation intervals of 2 days, but the variability increases. Midseason drainage was not found to affect yield, though non-flooded conditions when maintained throughout most of the crop season appeared to be detrimental to yields. Increasingly negative effects on yields were found when increasing the severity of AWD or the length of the drainage periods. Potential benefits and drawbacks of water-saving irrigation management with regards to greenhouse gas emissions, soil quality and nutrient losses were discussed to highlight the complexity of the challenges of saving water in rice production.
19

Zdravotně technické instalace s nízkou spotřebou vody a energie / Plumbing Systems with Low Water and Energy Consumption

Nikrmajer, Vojtěch January 2013 (has links)
The thesis deals with energy-saving plumbing systems. It is divided into three parts: task analysis, applications theme on the building and experiment. In the first part are described the possibilities of saving water and energy in the plumbing systems. The second part contains a comparison of some variants of saving solution water supply system and sanitary drainage system at the hotel. Part of the experiment investigates the water consumption for washing hands in addiction: the pressure in the water supply system and the type of mixing valves.
20

Zdravotně technické a plynovodní instalace v tělocvičně / The Sanitation installations and gas installations in a gym

Křoustek, Jiří January 2013 (has links)
The thesis deals with the topic of the Sanitation installations and gas installations in a gym. The core element of the theoretical part is the water saving while using the economical fixture in the building. The following point is the financial estimation. The thesis also deals with various options of solving the scheduled specialisation. Here, the two ways of proportioning and two ways of mixing the hot water for taking a shower are described in detail. The project part is trying to solve the sanitary technical and gas pipeline in a gym in the chosen version.

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