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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.
201

Integrated water management concept for craft villages - example from the food processing craft village Dai Lam / Đề án quản lý nước tích hợp cho làng nghề - Thí dụ từ làng nghề chế biến thực phẩm Đại Lâm

Hahn, Celia, Meier, Sebastian, Weichgrebe, Dirk, Tran, Thi Nguyet, Appel, Holger, Fechter, Leonhard, Werner, Peter 09 November 2012 (has links) (PDF)
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.
202

Studies and Development of Self-humidifying PEM Fuel Cell

Chen, Chun-Yu 05 September 2011 (has links)
¡@¡@In this thesis, we develop a self-humidifying PEMFC. The humidifying effects on the stability and impedance of the fuel cell are studied. A portable and passive PEMFC stack usually exposes in the ambient no matter that it works or not. However, the ambient is far from saturated. The water within MEA will diffuse to the membrane¡¦s surface and evaporate continuously. The membrane will be short in water without water supplying. Because the conductivity of H+ of the membrane is highly dependent on water content, the dehydration of the membrane will reduce the interconnected passageway of H+ and affect the performance of fuel cell directly. And because of the different expansion rate the electrode of MEA is also possible to separate from its membrane when it operates repeatedly. This separation will make the performance of fuel cell an unrecovered decay. ¡@¡@At first, the hydration status of the dry membrane is observed. We measure the addition weight of water into membrane by using cotton thread humidifying, and estimate the water permeation distances. The maximum water supply rate of cotton thread is 4.26mg/min, and the permeation rate of water through membrane where is 2.5cm from water surface is 0.15mg/cm¡Dmin. Then we design the self-humidifying devices of PEMFC stack. The humidifying effects on performance and stability of the fuel cell are studied. ¡@¡@When the active area is 0.7¡Ñ4.5cm2 and the cotton thread is 5mm from the center of electrode the supplying water can arrive at the reaction area under the electrode through the membrane in one minute. The difference of the supplying water between the bottom and top is 7% by using 6cm cotton thread. Therefore water can hydrate the membrane and the difference of the supplying water between bottom and top is not oversize. The higher current load, the voltage efficiency is lower. The increasing heat generation rate results in the water evaporation rate would be greater than the water generation rate. So the drop of voltage under higher current is greater than lower current. By comparing with the difference of high frequency impedance the change of humidifying is smaller between 1hr operating. It indicates that humidifying by cotton thread keeps the membrane hydration.
203

The Research of Hydrologic Management with GIS: A Case Study of the Aogu Wetland, Chiayi, Taiwan

Chang, Yu-Liang 08 September 2011 (has links)
Aogu Farm was built on reclaimed land. Because of its rich ecological resources, Aogu was defined as a "Major Wildlife Habitat" in Chiayi County by the Forest Service and is also expected to reduce carbon in the plan for the flatland forest. Power pumps are currently used to irrigate and cultivate the area. However, after becoming the Forest Recreation Area in the future, Aogu Farm has to reduce the influence of human beings. However, if the Taisugar Company doesn¡¦t support the plan of Forest Service or abandons farming and stops the pumping power, the Aogu Wetlands will suffer the crisis of coastal inundation. Hydrological models have their own characteristics. For example, inundation models for regional drainage using one-dimensional channel flow, two-dimensional overland flow, and runoff in the mountains all can be assessed to solve the inundation problems in the coastal lowlands. Nevertheless, the Aogu Wetlands, the Case Study area, has both a dry season and a wet season even in the lowland. When rainstorms occur, the area is unable to discharge the water by gravity but can depend only on pumps to discharge the water into the sea. Therefore, based on the need to manage water, hydrological surveys must be conducted to assess the hydrological impact of continuous rainfall on the Aogu Wetlands and to provide reference information to assist in the management. In the thesis, I use both the Geographic Information System (GIS) and the Storm Water Management Model (SWMM) as analysis tools. Moreover, the different regions are further divided into watershed and the route of drainage, establishing two kinds of models of watershed hydrology for precipitation simulations. Finally, to compare these two methods, the Arc Hydro and SWMM models are used in watershed analysis.
204

Simulating and Optimizing Storm Water Management Strategies in an Urban Watershed

Damodaram, Chandana 2010 December 1900 (has links)
Land development transforms the natural landscape and impacts in stream ecosystems and downstream communities as it alters the natural flow regime. An increase in impervious areas results in higher volumes of storm water runoff, reduced time to peak, and more frequent flooding. Best Management Practices (BMP) and Low Impact development (LID) are a few of the set of measures which are used to mitigate the impact of urbanization. Peak flow, runoff volume are few of the conventional metrics which are used to evaluate the impact and performance of these storm water management strategies on the watershed. BMP are majorly used to control the flood runoff but results in the release of large volumes of runoff even after the flood wave passed the reach and LIDs are used to replicate the natural flow regime by controlling the runoff at the source. Therefore need to incorporate a metric which includes the timing and area being inundated needs to be considered to study the impact of these strategies on the downstream. My proposed research will focus on simulating the Low Impact Development (LID) techniques like permeable pavements and rainwater harvesting on an urbanized watershed using a curve number approach to quantify the hydrologic performance of these strategies on the watershed. LID, BMPs, and combined strategies are introduced for retrofitting existing conditions and their hydrologic performance is accessed based on the peak flow and a new metric Hydrologic Footprint Residence. A simulation optimization framework would be developed which identifies cost effective LID options that maximize the reduction of peak flow from the existing condition design storms while meeting budget restrictions. Further LID and BMP placement is included in the optimization model to study the impact of the combined scenario on the storm water management plans and their performance based on different storms and corresponding budget. Therefore a tradeoff can be illustrated between the implementation cost and the hydrological impact on the watershed based on the storm water management approach of using only LID and combination of LID and BMP corresponding to varied spectrum of design storm events.
205

Decoupling Developmentalism-environmentalism: Human Nature Conceptualizations In Freshwater Ecosystems Management In Turkey

Ayas, Ceren 01 September 2009 (has links) (PDF)
Would it be possible to go one step further than proposing sustainable development as the ultimate answer where people live within nature harmoniously if natural resources were not managed by central authorities, who mostly are male, aged, middle-class bureaucrats? Bearing in mind that we have reached a stage where ecological credit crunch will define human&rsquo / s limits remarks for non-teleological and eco-friendly ways of conceptualizing the relationship between human beings and nature is explored with an emphasis of &lsquo / who&rsquo / that is local, female, young, social science-based, active in civil movement. The objective of conducting the research is to find out the ways why green approaches in social, political and economic spheres in Turkey are not integrated as a first step to decouple the antagonism in man&rsquo / s relationship with nature. The analysis tried to grasp the discrepancies of conceptualizing human-nature relationship in order to find out which segment of the society would be closer to adopt green values, with the intention of proposing them to be involved in a greater extent to decision-making mechanisms with regards to natural resources management, as well as an attempt to grasp the overall picture in understanding nature-human relationship in Turkey by focusing on wetland management based on the research conducted in Bafa Lake (Aydin), Uluabat Lake (Bursa), Salt Lake (Konya) and Egirdir Lake (Isparta). Thanks to the scale that is constructed by operationalizing the existing debates on environmental ethics, agents that would follow more ecologically sound discipline towards living harmoniously within nature is analysed.
206

The European Union Water Framework Directive And Turkey

Sumer, Vakur 01 September 2011 (has links) (PDF)
This thesis focuses on the relationship with the EU Water Framework Directive (WFD) and Turkey
207

Imazethapyr: red rice control and resistance, and environmental fate

Avila, Luis Antonio de 01 November 2005 (has links)
Imazethapyr was recently approved for use in rice, but limited information is available regarding its efficacy, environmental fate or potential red rice resistance. Therefore, experiments were conducted to 1) determine the effect of flooding time, and stage of imazethapyr application in red rice control, 2) assess the acetolactate synthase resistance to imazethapyr on red rice ecotypes, 3) determine the relative photolysis of imazethapyr, and 4) determine the effect of soil and moisture on imazethapyr adsorption and availability. When imazethapyr was applied in sequential application of PRE followed by a POST application, to achieve >95% red rice control, flood needed to be established within 14 DAT when imazethapyr was applied EPOST, and 7 DAT when imazethapyr was applied LPOST. Delaying the flood up to 21 DAT reduced rice grain yield for both EPOST and LPOST application timings. Based on enzymatic activity, the mean I50 values were 1.5, 1.1, 1.5, 1.6, 20.8, and 590.6 mM of imazethapyr, respectively, for LA 5, MS 5, TX 4, ??Cypress??, ??CL-121??, and ??CL-161??. CL-161 was 32 times more resistant than CL-121, and at least 420 times more resistant than the average of the red rice ecotypes and ??Cypress??. Results from the ALS assay showed that red rice ecotypes and Cypress had high susceptibility to imazethapyr when compared with the tolerant CL-121 and the resistant CL-161. Measurable enzymatic tolerance to ALS-inhibiting herbicides has not yet developed in these red rice ecotypes. Imazethapyr quantum yield (fI ) was 0.023 ?? 0.002 while the hydroxyl radical rate constant ( I OH k?? ) was 2.8 ?? 0.44 x 1013 M-1 h-1. These results show that imazethapyr is susceptible to both direct and indirect photolysis. The results also show that imazethapyr photolysis in paddy water will be affected by turbidity due to its impact on the availability of sunlight to drive direct and indirect photolysis reactions. Imazethapyr was more available and more concentrated in sandy soil. With higher amounts of water in soil there was greater amount of imazethapyr in soil solution and a lower concentration of herbicide due to dilution. The double centrifuge method provided a better estimate of plant available herbicide.
208

Challenges in low-temperature fuel cells

Gallagher, Kevin Gregory 14 August 2009 (has links)
Low-temperature fuel cells (LTFC) such as phosphoric acid fuel cells (PAFC) and proton exchange membrane fuel cells (PEMFC) are a promising electrochemical energy system for the conversion of hydrogen to electricity. Many challenges must be overcome before commercialization is possible. This dissertation focuses on the degradation of carbon catalyst supports and PEMFC water management. Kinetic studies are presented on the structure-reactivity relationship including an in-depth study of commercially available and model carbons. A mechanism and numerical model of the electrochemical oxidation of graphene-based carbon is proposed to explain longstanding questions. Three mechanisms are concluded to contribute to the current decay commonly observed during electrochemical oxidation: mass loss, reversible passive oxide formation, and irreversible oxide formation. Water uptake and electro-osmosis are investigated to improve the understanding and aid modeling of water transport in PEMFCs below 0 °C. The implication of an electro-osmotic drag coefficient less than unity is discussed in terms of proton transport mechanisms. Capillary pressure saturation relations are presented for carbon fiber paper which can both be used as gas-diffusion layers in PEMFCs. Boundary and scanning curves for imbibition and drainage are measured to further understanding of the hysteresis observed during PEMFC operation.
209

From public pipes to private hands : water access and distribution in Dar es Salaam, Tanzania /

Kjellén, Marianne, January 1900 (has links)
Diss. Stockholm : Stockholms universitet, 2006.
210

Why is collective participation not progressing in irrigation water management systems in India today? : case study Distributary 54 in Tungabhadra River Project, Karnataka, India /

Simonsen, Mai. January 2008 (has links) (PDF)
Master's thesis. / Format: PDF. Bibl.

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