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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.
431

Urbanisticko – architektonická studie areálu pro šetrný turismus Strachotín / Eco-friendly tourism complex Strachotín – urban and architectural study.

Panáčková, Miroslava January 2019 (has links)
This diploma thesis is focused on the urban design of the selected area in the village Strachotín and the architectural design of the building in the given locality. The aim of the proposal is to connect the building with regard to the surrounding landscape and to make the locality more attractive to tourists around the northern shore of Nové Mlýny reservoirs. The design concept is based on the modular arrangement of the individual parts of the object. Functional layout is represented by a hotel, wellness, restaurant and cosmetics production.
432

Impact of Water Management and Agronomic Practices on the Performance of Insecticide Seed Treatments against Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, in Mississippi Rice

Adams, Charles Andrew 11 May 2013 (has links)
Two field trials were conducted to determine the impact of water management on the efficacy of insecticide seed treatments against rice water weevil, Lissorhoptrus oryzophilus Kuschel, in rice at the Delta Research and Extension Center during 2011 and 2012. The performance of thiamethoxam, chlorantraniliprole, and clothianidin was evaluated when the permanent flood was established at different timings (6 and 8 weeks after planting) and the effect of flush number (0, 1, or 2) on seed treatment performance was evaluated. Seed treatment efficacy was not impacted by delayed flooding, but 2 flushes reduced efficacy of some seed treatments. Experiments were also conducted to determine the impact of reduced seeding rates found in hybrid rice production on the efficacy of insecticide seed treatments targeting rice water weevil. Efficacy was similar when comparing currently labeled rates of thiamethoxam, chlorantraniliprole, and clothianidin with higher rates of these products.
433

Water Management in the PEM Fuel Cell by Incorporating a Novel Siloxane Polymer in the Electrode Layer

Yen, Shen-An January 2012 (has links)
No description available.
434

A Swat-Based Decision Support System for Multipurpose Reservoir Operation and Food-Water-Energy-Environment Trade-Off Analysis: Case Study of Selingue Reservoir

Sia, Edgard Tisson 25 April 2023 (has links)
The world's water resources face unsustainable pressure from population growth, changes in consumption patterns, pollution, and overexploitation. Water resources managers have developed holistic approaches such as IWRM (Integrated Water Resources Management) and, more recently, the WEEF (Water-Energy-Environment-Food) nexus to address the situation. However, their application in day-to-day water resources management is still challenging due to the of little knowledge, data, and tools. One area where that challenge needs practical solutions is reservoir operation. The current study aims to improve the reservoir module in the Soil and Water Assessment Tool (SWAT) so that operation rules that aim to meet various water, food, and electricity objectives can be simulated. The improved SWAT model is used to simulate the management of the Sélingué reservoir in Mali, West Africa. The reservoir operation was simulated under three different operation rules: 1) priority to monthly hydropower production (HPP) target (rule 1); 2) respect of predefined monthly target storage (rule 2); 3) priority to downstream environmental flow, irrigation, and municipal water demands (rule 3). Results show that when priority is given to the HPP target (rule 1), 98.3% of the electricity demand is met. At the same time, the dam can supply 81.72% of the water demand to maintain environmental flow and sustain irrigation and municipal water consumption. It also ensures water availability with an annual target storage deviation estimated at 1.8%. When rule 2 is implemented, a gap of 8.5% between electricity production and electricity demand is observed. Rule 2 also failed to sustain environmental flow and supply flow for irrigation and municipal consumption as a gap of 15.39% between the supply and the demand was observed. Similarly to rule 1, It ensures water availability with an annual target storage deviation estimated at 1.25%. When rule 3 is enforced (i.e., the priority is given to environmental flow, irrigation, and municipal water demands) the reservoir can maintain the environmental flow and maintain irrigation, and municipal water requirements with a gap of 17.7% between the supply and the demands. However, HPP production decreases with a gap of 12.56% between the electricity supply and demand. Its capacity to supply water in the long term is low as it has the highest target storage deviation with a value of 18%. These results indicate that rule 1 offers more guarantees considering the food and electricity security and environmental challenges. Note that the simulations are done assuming that these rules are systematically followed. In practice, decision-makers can deviate from a rule in exceptional circumstances to maximize benefits or avert unwanted consequences. Finally, a decision support system (DSS) was developed to assist decision-makers in selecting efficient reservoir operation policies for multipurpose reservoirs combining HPP and irrigation.
435

Efficiency of sustainable urban drainage systems during flash floods / Effektivitet av hållbara dagvattensystem vid skyfall

Axelsdóttir, Snærós January 2022 (has links)
As the world’s population is migrating more into urban areas, landcover changes follow. Natural pervious areas are being converted to impervious areas, which when subjected to rain generates more stormwater runoff. Stormwater management is a problem that cities today are challenged with, infrastructure is getting older and precipitation patterns are changing due to climate change. Due to climate change extreme precipitation events are likely to increase and therefore increase the probability of urban flooding. Urban flooding can be caused by extreme precipitation events with a short duration, or so-called flash floods. These flash floods can overwhelm the drainage system in place which therefore can cause flooding. This problem has inspired engineers to rethink stormwater management, moving from traditional grey drainage systems to more green and sustainable drainage systems. Sustainable Urban Drainage System (SuDS) are drainage systems that aim to regain the properties of non-urbanised areas, retain the natural hydrological cycle, and have recreational values for the surrounding societies. This study investigated how different SuDS behave when subjected to flash floods. A model of a synthetic case study was built in the Storm Water Management Model (SWMM) and sustainable urban drainage systems implemented. The solutions investigated were bioretention cells, rain gardens, infiltration trenches, green roofs, and permeable pavements. Three different rain events were analysed, all with different precipitation depth but with the same duration of 1 hour. Results showed that bioretention cells could reduce runoff volumes to the highest extent while green roofs could reduce the peak runoff the most. Other results were analysed like efficiency and cost. Bioretention cell came out on top in efficiency but had the highest cost. Overall, all the solutions showed promise in reducing runoff during flash floods, but the reduction capacity goes down with increased precipitation. / När en större del av världens befolkning flyttar in till tätortsområden så medföljer en ändring av markytans beskaffenhet. Vanligtvis genomträngliga ytor omvandlas till hårdgjorda ytor vilket generar mer dagvattenavrinning när de utsätts för regn. Dagvattenhanteringen är en utmaning för många städer idag eftersom infrastrukturen blir äldre och nederbördsmönstren förändras på grund av klimatförändringar. Extrema nederbördshändelser väntas öka med anledning av dessa klimatförändringar och ökar därigenom sannolikheten för översvämningar i städer. Översvämningar i städer kan orsakas av korta nederbördshändelser med hög intensitet, så kallade Skyfall, vilket kan överbelasta dagvattensystemets kapacitet. Det har lett till att ingenjörer ändrat sitt tankesätt på hur dagvatten ska hanteras och börjat gå från konventionella till mer gröna och hållbara dräneringssystem. Hållbar dagvattenhantering är dräneringssystem som syftar till att använda egenskaperna hos naturliga områden, behålla det naturliga hydrologiska kretsloppet och skapa rekreationsvärden för de omkringliggande samhällena. Denna studie har undersökt hur olika hållbara dräneringssystem beter sig när de utsätts för översvämningar. En modell på en syntetisk fallstudie byggdes i Storm Water Management Model (SWMM) där hållbara dräneringssystem implementerades i en urban miljö. Lösningarna som undersöktes var biofilterbäddar, regnträdgårdar, infiltrationsbäddar, gröna tak och permeabla trottoarer. Tre olika nederbördshändelser analyserades, alla med olika nederbördsmängder men med samma varaktighet på en timme. Resultaten visade att biofilterbäddar kunde minska avrinningsvolymerna i största grad medan gröna tak minskade ytavrinningen mest. Effektivitet och kostnad analyserades också. Där visade biofilterbäddarna högst effektivitet men hade den högsta kostnaden. Sammantaget visade det sig att alla lösningar var lovande vad gäller minskning av avrinning under översvämningar, men reduktionskapaciteten minskar med ökad nederbörd.
436

Hållbar Dagvattenhantering på Kvartersmark : En utvärdering av hur väl den planerade dagvattenhanteringen fungerar i verkligheten / Sustainable Stormwater Management in Residential Areas : An evaluation of how well the planned stormwater management functions in reality

Andersson, Josefin January 2017 (has links)
Storm water management in residential areas is facing tough challenges. Climate change, with its altered precipitation patterns, in combination with an increasing development rate, results in higher risk of flooding with its complications. EU-Water Framework Directive (WFD) and its environmental quality standards, set to achieve good chemical and biological status in all waters, got a more strict interpretation after the implementation of the ruling of Weserdomen. This means that no activity is allowed that cannot prove not to endanger prevailing environmental quality standards. This complicates the planning process and infrastructure development since some form of WFD assessment needs to be performed.   This master´s thesis is of importance since it identifies common occurring problems within the planning- and construction process and highlights ways to achieve a more sustainable storm water management, where environmental quality standards are not jeopardized, in the future. An evaluation is performed in terms of interviews, a literature review and by using a storm water model called StormTac applied on two case studies. Results of this thesis show that lack of communication, vague directives, inadequate design and maintenance of storm water facilities are reasons that a sustainable storm water management is not achieved.   Results from modeling the storm water situation prior to construction of the residential areas were set as benchmarks, which were not to be exceeded by results from modeling areas after construction. The purpose of this was to not endanger the current storm water state and thereby not risk violating prevailing environmental quality standards. The result from modeling the storm water situation after construction shows that both case studies exceed the flow and pollution load benchmarks. Because of this, solutions to the current storm water situation was created and modeled to achieve the study aim.   StormTac can be applied as a tool for comparison of flow and pollution load prior to and after construction, given that the same land uses are used in both cases. Land use choices should be evaluated and the degree of uncertainty should be considered when interpreting the results. / Dagvattenhantering på kvartersmark står inför stora utmaningar. Klimatförändringar medför ändrade nederbördsmönster med intensivare skyfall som i kombination med en allt högre exploateringsgrad ökar risken för översvämningar och dess negativa konsekvenser. EU:s ramdirektiv för vatten och beslutade miljökvalitetsnormer anger att god status ska uppnås i samtliga vattenförekomster. Införande av Weserdomen resulterar i en strängare tolkning av försämringsförbudet, som råder vid statusklassificeringen, vilket i sin tur gör att befintlig dagvattensituation inte får försämras. Detta gör att planeringsskede, anläggning och faktisk funktion hos implementerade dagvattenlösningar fått ett allt mer hållbart fokus.   Detta examensarbete är av vikt då det identifierar problem i plan- och byggprocessen samt belyser hur dessa kan undvikas för att uppnå en mer hållbar dagvattenhantering i framtiden. En utvärdering är utförd i form av intervjuer och litteraturstudie samt dagvattenmodellering i modelleringsverktyget StormTac av två fallstudier. Resultat visar att kommunikation, otydliga direktiv, bristfällig utformning och skötsel av dagvattenanläggningar är orsaker till att dagvattenhanteringen inte uppnår rening- och flödesutjämningsbehov enligt miljömål och – krav.   Resultat från modellering av dagvattensituationen före exploatering sattes som referensvärden som inte får överskridas vid modellering av området efter exploatering, för att befintlig dagvattensituation skulle säkerställas att inte försämras. Resultat av modellering efter exploatering överskred referensvärden i båda fallstudierna och därmed modellerades scenarier med dagvattenhanteringsförslag för att uppnå målsättning.   StormTac fungerar som ett verktyg för att jämföra flödes- och föroreningsbelastning före och efter exploatering, förutsatt att samma markanvändningstyper används. Val av markanvändning bör ses över och osäkerheter hos resulterande flödes- och föroreningsmängder bör tas hänsyn till.
437

Turning Smart Water Meter Data Into Useful Information : A case study on rental apartments in Södertälje

Söderberg, Anna, Dahlström, Philip January 2017 (has links)
Managing water in urban areas is an ever increasingly complex challenge. Technology enables sustainable urban water management and with integrated smart metering solutions, massive amounts of water consumption data from the end users can be collected. However, the possibility of generating data from the end user holds no value in itself. It is with the use of data analysis the vast amount of the collected data can provide more insightful information creating potential benefits. It is recognized that a deeper understanding of the end user could potentially provide benefits for operational managers as well as for the end users. A single case study of a data set containing high frequency end user water consumption data from rental apartments has been conducted, where the data set was analyzed in order to see what possible information that could be extracted and interpreted based on an exploratory data analysis (EDA). Furthermore, an interview with the operational manager of the buildings under study as well as a literature review have been carried out in order to understand how the gathered data is used today and to which contexts it could be extrapolated to provide potential benefits at a building level. The results suggests that the EDA is a powerful method approach when starting out without strong preconception of the data under study and have successfully revealed patterns and a fundamental understanding of the data and its structure. Through analysis, variations over time, water consumption patterns and excessive water users have been identified as well as a leak identification process. Even more challenging than to make meaning of the data is to trigger actions, decisions and measures based on the data analysis. The unveiled information could be applied for an improved operational building management, to empower the customers, for business and campaign opportunities as well as for an integrated decision support system. To summarize, it is concluded that the usage of smart water metering data holds an untapped opportunity to save water, energy as well as money. In the drive towards a more sustainable and smarter city, smart water meter data from end users have the potential to enable smarter building management as well as smarter water services.
438

Storm Water Management with BlueGreen Infrastructure in Urban Planning : A case-study in Krokom, Sweden

Suleiko Allansson, Lena January 2023 (has links)
As changing climate and growing urban populations present new challenges for managing both the quantity and the quality of storm waterin cities, nature-based solutions such as blue-green infrastructure arebecoming widely considered as an alternative to grey infrastructure. The benefits, above providing storm water management at a lower cost, are increased ecosystem services. One of such solutions is SuDS: a collective name for drainage systems thatare designed to manage the quantity of runoff, protect or enhance water quality, increase amenity and foster biodiversity. In Sweden there is a lack of research on applying nature-based solutions in planning urban water management. This case study aims to contribute with knowledge of how working with blue-green infrastructure in a systematic way effects the outcome of urban planning and what ecosystem gains can be expected. ASuDS design was created following the SuDS guidelines for a greenfield residential area in the city of Krokom. The design was then compared with the original proposal by the municipality.The results show that the systematic method that SuDS brings to watermanagement planning leads to a different design of a residence area than what traditional methods produce. At the same time the ability to handle extreme rain event is at least as robust, with the ability of the system to generate other ecosystem services and further strengthen the resilience of the area. Further research is needed for a more detailed analysis of the generated ecosystem services. / <p>2023-06-02</p>
439

Long-term evolution of highly regulated basins and water management policies to support their ecosystem services

Hinegk, Luigi 07 October 2022 (has links)
Water management is facing a growing number of challenges in many river basins worldwide, as the equal distribution of the available water resources is increasingly influenced by several, uncertain climatic and anthropic pressures. Within the current and projected water scarcity and drought scenario, such issue represents even a greater challenge in those basins that have been massively regulated in the XX century, as water managers are asked to find balanced policies to stay ahead with multiple, interdependent and ever-increasing water-related requirements. In this context, water conflict has become a recurring problem, with the freshwater ecosystems becoming the sole providers of unbearable human water needs and experiencing a severe alteration of their natural renewability and ecological integrity. In fact, the concern of sustaining the freshwater ecosystems has evolved throughout the years, coming to the fore since the 1990s under the concept of "ecosystem services", defined as the multiple benefits that people obtain from ecosystems. With a high number of challenges still ahead for implementing such paradigm in real-world water management practices, few investigations inspect the long-term evolution of highly regulated basins, being vulnerable freshwater systems characterized by a profusion of ecosystem services in a context of complex management policies and changing anthropic and climatic pressures. We focus our attention on the highly interconnected Garda-Mincio system (Northern Italy), further broadening the results to the regulated basins of the European perialpine region. First, to examine the modification of the freshwater systems from their pristine to their regulated conditions, we carried out an extensive collection of daily hydro-meteorological data by consulting public online sources as well as digitizing historical data contained in hand-written documents. The resulting database, which represents a valuable source of long-term daily hydro-meteorological data for the Garda-Mincio system, additionally underscored the complexity of constructing and maintaining a consistent and up-to-date database within an inter-regional context. The collected data were then adopted to investigate the climatic and anthropogenic drivers that have progressively influenced water availability, the provision of the changing water demands and the trade-offs with the existing water ecosystem services over the last two centuries. Statistical analyses were performed to outline the evolution of the annual and seasonal trends of Lake Garda water levels and outflows over the period 1888-2020, discussing the role of the Salionze Dam operational rules (completed in 1951) as well as the influence of the main water needs of the downstream Mincio River basin (i.e. hydropower production, irrigation and fluvial ecosystem sustenance). The role of hydro-meteorological factors was assessed by implementing a water balance model for Lake Garda, the largest lake in Italy, over the period 1928-2020, performing uncertainty and sensitivity analyses on specific water balance components (i.e. over-lake evaporation and basin evapotranspiration). We then focus our analyses on the management of the hydraulic infrastructures that regulate the first and highly water-stressed stretch of the Mincio River downstream Lake Garda, i.e. the Salionze Dam and the Pozzolo-Marenghello infrastructures, where both high and low flow conditions reveal the inability of the current operational rules to support the new variety of water abstractions while maintaining appropriate environmental flow conditions and flood protection. These analyses were carried out through in-situ measurements and numerical simulations, updating the aging rating curves of the existing hydraulic infrastructures. Drawing on the Garda-Mincio system, we inspected the evolution of the freshwater regimes within the European perialpine lakes framework, discussing the outcomes to describe which common factors drove management policies in the area. Eventually, we discuss our outcomes recommending future sustainable and adaptive water management policies in the area.
440

Integrated water management concept for craft villages - example from the food processing craft village Dai Lam: Short communication

Hahn, Celia, Meier, Sebastian, Weichgrebe, Dirk, Tran, Thi Nguyet, Appel, Holger, Fechter, Leonhard, Werner, Peter 09 November 2012 (has links)
Craft villages played a significant role in the development of Vietnam’s rural economy for a long time. The range of products and production methods, including the processing of materials and chemicals, are now adapted to modern market requirements but environmental and labour protection issues are not adequately considered in the management of the craft villages. The reasons are various: poor education of responsible operators, deficient technical equipment or missing regulatory framework and implementation of existing regulations. The INHAND project (Integrated Water Management Concept for Craft Villages) started in 2011 and is studying the food processing village of Dai Lam located on the banks of the Cau River in the Bac Ninh province (about 40 km NE of the capital Hanoi). The household-scale business focus mainly on rice and cassava processing with 200 out of 1000 households producing alcohol from cassava and rice, 10 households producing tofu, and 30 households recycling aluminium. In addition, most households also raise pigs. The wastewater is released mostly untreated into the receiving stream. Within the framework of the INHAND project, four German und two Vietnamese partners will conduct a basic analysis inventory in the village with identification of suitable measure for an integrated, environmentally sound concept for the removal and reuse of all output streams. The second major task of the 3.5 years research project is the conceptualisation, development and implementation of pilot-scale treatment facilities in the village and the scientific monitoring of their planning and operation. / Đã từ lâu, làng nghề đóng vai trò quan trọng trong quá trình phát triển kinh tế nông nghiệp tại Việt Nam. Các sản phẩm và phương thức sản xuất, bao gồm cả giai đoạn xử lý vật liệu và hóa chất, đã từng bước được cải tiến cho phù hợp với yêu cầu của thị trường hiện đại. Tuy nhiên, những yếu tố về môi trường và an toàn lao động vẫn chưa được quan tâm đúng mức tại các làng nghề do nhiều nguyên nhân như: trình độ của nhà sản xuất, vận hành còn hạn hẹp, thiếu trang thiết bị kỹ thuật, các quy chuẩn còn thiếu hoặc chưa được thi hành triệt để. Dự án INHAND (đề án xử lý nước tổng thể cho làng nghề) được khởi động từ năm 2011 và hiện đang tiến hành nghiên cứu làng nghề chế biến thực phẩm Đại Lâm ,nằm bên bờ song Cầu, thuộc tỉnh Bắc Ninh, cách Hà Nội 40 km. Mô hình kinh tế hộ gia đình tại làng chủ yếu tập trung vào chế biến gạo và sắn: 200 trong số 1000 hộ gia đình nấu rượu gạo và sắn, 10 hộ sản xuất đậu phụ, 30 hộ tái chế nhôm. Ngoài ra, gần như tất cả các hộ đều có nuôi lợn. Nước thải của làng được dẫn trực tiếp ra các khối nước mở, gần như không qua xử lý. Trong khuôn khổ dự án INHAND, bốn đối tác Đức và hai đối tác Việt Nam sẽ tiến hành phân tích hiện trạng môi trường của làng để tìm ra những biện pháp thích hợp nhằm xử lý và tái sử dụng các dòng thải. Nhiệm vụ thứ hai trong thời gian 3,5 năm của dự án là lập ra đề án, phát triển và triển khai các trạm xử lý ở quy mô thử nghiệm, đồng thời quan trắc khoa học các quá trình thiết kế và vận hành.

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