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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.
281

Návrh víceúčelové nádrže v k.ú. Popovice / The design of the multipurpose small water reservoir

Pitka, Roman January 2013 (has links)
Master´s thesis aims to design multipurpose reservoirs in the river basin Žlebovský potok in cadastre Vysoké Popovice. The main purpose of the reservoir will be improving the drainage conditions in the basin of the river and revitalization. The reservoir will be designed according ČSN 75 2410 – Malé vodní nádrže. The master´s thesis consists of a text section, hydraulic calculations and graphic attachments.
282

Posouzení malé vodní nádrže Točenka / Assessment of the Točenka small reservoir

Ďurďa, Eduard January 2016 (has links)
The main priority thesis is to evaluate the current status and future follow- variant solution functions and the resulting operating small water reservoir Točenka in Babice u Kelč. Thanks smyvům of the field lines in the upper part of the basin has been a complete clogging the tank up to the spillway . Task is to assess the current status of the tank and identify measures for future use.
283

Growing Up Deaf in Appalachia: An Oral History of My Mother

Tipton, Elizabeth Shelton 01 December 2019 (has links)
This study focuses on the life experiences of a rural, Deaf Appalachian woman, Jane Ann Shelton, a second generation Deaf child born to Deaf parents from the communities of Devil’s Fork (Flag Pond, Tennessee) and Shelton Laurel (Madison County, North Carolina). Over two hours of videotaped interviews were interpreted and transcribed, followed by various other communications to describe the life of a rural, Deaf Appalachian woman without a formal high school degree. As an advocate and a political lobbyist in Tennessee during the 1980s and 90s, she was unparalleled by her peers (deaf or hearing) in her efforts to “enhance the lives of ALL Deaf Tennesseans.” From these interactions and my firsthand knowledge, I crafted stories of her life experiences for the purpose of performing them for both Deaf and hearing audiences. Further studies should be done on rural Deaf Appalachia as precious little oral history has been collected.
284

What Comes After the Blues

Kurtz, Matthew B. 17 June 2021 (has links)
No description available.
285

Revitalizace rybníka v katastrálním území Skalička u Hranic / Revitalization of the Small Water Reservoir in the Skalička u Hranic Cadastral Area

Majkus, Martin January 2022 (has links)
The aim of this paper is to propose a comprehensive revitalization of the side pond in the cadastral area of Skalička. As part of revitalization measures, the removal of mud from the pond, fortification of the banks and other modifications in connection with functional structures are proposed. In order to take water into the pond, a concrete diversion structure in the Hlubocky stream bed is designed, connected with pond via open canal with 2 pools, which will substitute the existing supply pipeline. As part of stabilization of the streambed and to overcome height difference, a boulder chute with stilling basin and related modifications are designed. The introductory part is a summary of knowledge from the issue and it explains important terms, historical context and description of basic principles. The next part describes the current situation and conditions in the surveyed locality. The following is a description of the methods and programs that were used for this work. The design part presents the proposed revitalization measures. An essential part of the work is also the varification of the proposed modification in the streambed, using 3D digital terrain model in Atlas DMT and subsequent 1D flow simulation in HEC-RAS.
286

Greenhouse gas emissions and carbon burial in a small pond / Växthusgasutsläpp och kolbindning i en liten damm

Carlson, Maria January 2023 (has links)
There are a lot of uncertainties when it comes to global greenhouse gas (GHG) emissions which affects society’s ability to effectively respond to climate change. Small ponds have been found to potentially play a large role in global warming. More research is needed, however, to determine to what extent they act as sources or sinks for GHGs, and what factors may contribute. The aim of this thesis was to study carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions, and carbon burial in a small pond in Uppsala, Sweden. The pond was a source for both CO2 and CH4, but a sink for N2O. About 50% of CH4 emissions came from ebullition (bubbles). CO2 flux was higher in the vegetated area than in the open water area, no difference was found for CH4 flux. Both CO2 and CH4 flux were higher on colder days, while CH4 ebullition was higher on warmer days. Limited accumulation of CO2 and CH4 occurred under the winter ice coverage. For water chemistry, CO2 flux had the strongest negative relationship with electrical conductivity (EC), nitrate (NO3−) and nitrite (NO2−), and positive with total phosphorous (TP). CH4 flux showed the strongest negative correlation with chlorophyll-a (chl-a) and total nitrogen (TN), and positive with EC and total dissolved solids (TDS). For extracellular enzyme activity, CO2 flux had a very strong positive correlation with β-D-glucosidase (BG), as did CH4 with N-acetyl-β-D-glucosaminidase (NAG). Carbon burial rate was low making the pond a carbon source and inefficient at burying carbon / Det finns många osäkerheter vad gäller globala utsläpp av växthusgaser vilket påverkar samhällets förmåga att effektivt motarbeta den globala uppvärmningen. Små dammar har potentiellt förmågan att ha en stor påverkan på klimatet, men mer forskning behövs för att avgöra i vilken utsträckning de fungerar som källor eller sänkor för växthusgaser, samt vilka faktorer som påverkar deras utsläpp eller förmåga att binda kol. Målet med denna studie var att undersöka utsläpp av koldioxid (CO2), metan (CH4) och lustgas (N2O), samt kolbindning i en liten damm i Uppsala, Sverige. Dammen var en nettoutsläppare av CO2 och CH4, men en nettoupptagare av N2O. CH4 i form av ebullition (bubblor) stod för ungefär 50% av CH4 utsläppen. CO2 flödet var högre i områden med växtlighet jämfört med områden med öppet vatten, för CH4 hittades ingen skillnad mellan dessa områden. Under kallare dagar var CO2 och CH4 flödet högre, medan ebullition av CH4 var högre under varmare dagar. Under vintern skedde minimal ackumulation av CO2 och CH4 under istäcket. För vattenkemin hade CO2 flödet starkast negativ korrelation med elektrisk konduktivitet (EC), nitrat (NO3−) och nitrit (NO2−), och positiv korrelation med totalfosfor (TP). CH4 flödet visade det starkaste negativa förhållandet med klorofyll a (chl-a) och totalkväve (TN), och positiv korrelation med EC och totalt upplösta fasta ämnen (TDS). För extracellulär enzymaktivitet hade CO2 flödet en mycket stark positiv korrelation med β-D-glucosidase (BG), medan CH4 flödet hade en mycket stark positiv korrelation med N-acetyl-β-D-glucosaminidase (NAG). Kolbegravningshastigheten var låg vilket resulterade i att dammen var en kolkälla med låg förmåga att binda kol.
287

Sustainable stormwater management in Stockholm's inner city / Hållbar dagvattenhantering i Stockholms innerstad

Brattgård, Nils January 2021 (has links)
Much like other cities Stockholm has traditionally used a technical system for managing stormwater. With time this system has become overburdened and has led to large environmental concerns. To reach water quality goals set by the EU Stockholm needs to decrease pollution released to recipients by 70-80%.  Green infrastructure (GI) has increasingly been used as an alternative and addition to technical stormwater systems. Many studies have been conducted on different solutions and their stormwater management performance. The City of Stockholm have done research on numerous solutions to evaluate their performance in the context of Stockholm as well. However, implementation in the inner city is slow, thus this study explores why this is the case, and how Stockholm’s stormwater management goals can be reached. Stockholm predominately uses trees planted in plant beds using structural soil, and a combination of constructed wetlands and wet ponds for stormwater management. In new developments there is no real concern, as the GI can be included in planning at an early stage. Including these solutions in existing environments causes issues related to space, both above and below ground, and costs. Therefore, other solutions need to be found. This study explored green roofs, green walls and permeable pavements as possible options. Additionally, it found that finding new space that has previously not been used for GI could be an option. To mitigate financing issues new ways of promoting investment into GI from private property owners could be utilized, but that there also is a mismatch between supposed support for sustainable stormwater management on the political side and funds allocated. Finally, the study recommends that Stockholm takes the technical systems into account and explores what GI measures best work together with it to more effectively decrease pollution.
288

The Effectiveness of a Stormwater Detention Pond in Enhancing Water Quality

Droppo, Ian Gerald 04 1900 (has links)
This research paper fulfills the requirements of Geography 4C6. / This paper is an introductory study on the ability of a detention pond to reduce pollutant loading to a receiving water body. Three forms of water pollution are analysed in this study, trace metal (V, Ti and Mn in the water and on suspended solids and bottom sediments), organic and bacterial (bacterial indicators of fecal coliform and fecal streptococci are utilized) pollutants. Each pollutant type requires a different form of analysis to obtain concentrations for targeted pollutants. V, Ti and Mn concentrations were obtained from Instrumental Neutron Activation Analysis (INAA), organic concentrations were acquired by Electron Capture Gas Chromatography (ECGC) and bacterial concentrations were obtained from various laboratory techniques performed by technicians in the Microbiology Lab at McMaster University and in the Provincial Health Laboratories in Hamilton, Ontario. Suspended solid concentration are also analysed to determine the pond's effectiveness in reducing suspended solids load and thus the pollutants they carry. The Storm Water Management Model was used to estimate total pollutant loading into the pond via a combined sewer overflow (CSO). The pollutant concentrations obtained were analysed spatially through the sampling network and temporally between sampled dry and wet weather periods. The result of this study has led to the disturbing conclusion that the detention pond appears to have little or no effect on enhancing water quality. / Thesis / Bachelor of Science (BSc)
289

Study on treatment of domestic wastewater of an area in Tu Liem district, Hanoi, by water hyacinth: Research article

Pham, Khanh Huy, Nguyen, Pham Hong Lien 09 December 2015 (has links)
Domestic wastewater is one of the most interested environmental issues in Vietnam, especially in big cities and suburban residential areas. Most of the wastewater was not treated in the right way before discharging to environment. In this research, the author used water hyacinth as a main aquatic plant in aquatic pond model to treat wastewater. The experiment was operated continuously in 1 year with hydraulic retention time (HRT) is 11 and 18 days. Hydraulic loading rate (HRL) is 300 and 500 m3/ha/day, respectively. Treatment efficiency of the model for TSS is 90% (remaining 6 -12mg/l); COD, BOD5 is 63 - 81% (remaining 10 - 48mg/l); TP is 48 – 50% (remaining 3.5 - 9.8mg/l); TKN is 63 - 75% (remaining 8 - 17mg/l). Polluted parameters in effluent were lower than A and B levels of Vietnam standard QCVN 14: 2008/BTNMT and QCVN 40: 2011/BTNMT. The doubling time of water hyacinth in summer is 18days, and in autumn and winter is 28.5 days. Experiment results showed that we can use water hyacinth in aquatic pond to treat domestic wastewater with medium scale. We can apply this natural treatment method for residential areas by utilizing existing natural ponds and abandoned agricultural land with capacity up to 500m3/ha day. However, to get better efficiency we should combine with other aquatic plant species to treat wastewater and improve environmental landscape. / Nước thải – xử lý nước thải sinh hoạt hiện đang là một trong những vấn đề môi trường được quan tâm tại Việt Nam nhất là tại các thành phố lớn và các khu dân cư. Hầu hết lượng nước thải chưa được xử lý đúng cách trước khi thải ra môi trường. Trong nghiên cứu này, tác giả sử dụng mô hình hồ thủy sinh và sử dụng cây Bèo lục bình để xử lý nước thải sinh hoạt của một khu dân thuộc huyện Từ Liêm, tại khu vực này nước thải bị thải trực tiếp vào sông Nhuệ. Thực nghiệm đã được tiến hành trong khoảng thời gian một năm, trải qua các mùa của khu vực miền Bắc với hai chế độ vận hành HRT là 18 và 11 ngày, tương ứng với tải trọng thủy lực HRL là 300 và 500 m3/ha/ngày. Kết quả cho thấy mô hình thủy sinh sử dụng cây bèo lục bình cho kết quả tốt, hiệu suất xử lý với các chất ô nhiễm đạt được như sau: chất rắn lơ lửng đạt 90%, COD, BOD5 đạt 63 - 81%, Phốt pho tổng giảm tới 48 -50%, Nitơ tổng giảm tới 63 - 75%. Hàm lượng các chất ô nhiễm trong nước thải đầu ra của mô hình đều thấp hơn ngưỡng A và B của các tiêu chuẩn QCVN 14: 2008/BTNMT và QCVN 40: 2011/BTNMT. Bên cạnh đó tác giả cũng đã xác định định được tốc độ sinh trưởng của cây bèo tại khu vực miền Bắc là 18 ngày vào mùa hè và 28.5 ngày vào mùa thu đông. Kết quả nghiên cứu cho thấy có thể sử dụng bèo lục bình để xử lý nước thải sinh hoạt, với qui mô vừa và nhỏ và nên áp dụng cho các khu vực ven đô, nông thôn nơi có diện tích đất rộng hoặc tại các hồ sinh thái của các khu đô thị. Tuy nhiên, để hiệu quả tốt hơn ta cần kết hợp với nhiều loại thực vật thủy sinh khác để ngoài tác dụng xử lý nước thải mà còn tạo cảnh quan môi trường xung quanh.
290

ANOMALIES IN SENSOR NETWORK DEPLOYMENTS: ANALYSIS, MODELING, AND DETECTION

Abuaitah, Giovani Rimon 20 August 2013 (has links)
No description available.

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