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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.
691

Design of Low Impact Development and Green Infrastructure at Flood Prone Areas in the City of Miami Beach, FLORIDA, USA

Alsarawi, Noura 29 June 2018 (has links)
This thesis investigates the effectiveness of Low Impact Development Infrastructure (LIDI) and Green Infrastructure (GI) in reducing flooding resulting from heavy rainfall events and sea-level rise, and in improving stormwater quality in the City of Miami Beach (CMB). InfoSWMM was used to simulate the 5, 10, and 100-year, 24-hour storm events, total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) loadings, and in evaluating the potential of selected LIDI and GI solutions in North Shore neighborhood. Post-development results revealed a decrease of 48%, 46%, and 39% in runoff, a decrease of 57%, 60%, and 62% in TSS, a decrease of 82%, 82%, and 84% in BOD, and a decrease of 69%, 69%, and 70% in COD loadings. SWMM 5.1 was also used to simulate the king tide effect in a cross section in Indian Creek Drive. The proposed design simulations successfully demonstrated the potential to control flooding, showing that innovative technologies offer the city opportunities to cope with climate impacts. This study should be most helpful to the CMB to support its management of flooding under any adaptation scenarios that may possibly result from climate changes. Flooding could be again caused as a result of changes in inland flooding from precipitation patterns or from sea-level rise or both.
692

Sediment Removal from the San Gabriel Mountains

Ferguson, Mary C 01 May 2012 (has links)
The issue of sediment removal from the San Gabriel Mountains has been a complex issue that has created problems with beach replenishment, habitat destruction and the need to spend millions of dollars at regular intervals to avoid safety hazards. Most recently 11 acres of riparian habitat, including 179 oaks and 70 sycamores, were removed for sediment placement. Other sites including Hahamongna Watershed Park and La Tuna Canyon also face a similar fate. This thesis questions: How did we get to this point of destroying habitat to dump sediment which is viewed as waste product? What are the barriers for creating long term solutions and progressive change? What are some other options? And how should we move forward? The issues with sediment management have stemmed from regulatory compliance issues, adversarial relationships within agencies and among NGO's and the public, and the lack of a comprehensive long-term plan to prevent further habitat loss and other sediment removal issues. A recommendation includes looking at a community forestry model to include a wide cross-section of the community, NGO's and government agencies to come up with a long term comprehensive and progressive solution.
693

MAPPING AND DECOMPOSING SCALE-DEPENDENT SOIL MOISTURE VARIABILITY WITHIN AN INNER BLUEGRASS LANDSCAPE

Landrum, Carla 01 January 2013 (has links)
There is a shared desire among public and private sectors to make more reliable predictions, accurate mapping, and appropriate scaling of soil moisture and associated parameters across landscapes. A discrepancy often exists between the scale at which soil hydrologic properties are measured and the scale at which they are modeled for management purposes. Moreover, little is known about the relative importance of hydrologic modeling parameters as soil moisture fluctuates with time. More research is needed to establish which observation scales in space and time are optimal for managing soil moisture variation over large spatial extents and how these scales are affected by fluctuations in soil moisture content with time. This research fuses high resolution geoelectric and light detection and ranging (LiDAR) as auxiliary measures to support sparse direct soil sampling over a 40 hectare inner BluegrassKentucky (USA) landscape. A Veris 3100 was used to measure shallow and deep apparent electrical conductivity (aEC) in tandem with soil moisture sampling on three separate dates with ascending soil moisture contents ranging from plant wilting point to near field capacity. Terrain attributes were produced from 2010 LiDAR ground returns collected at ≤1 m nominal pulse spacing. Exploratory statistics revealed several variables best associate with soil moisture, including terrain features (slope, profile curvature, and elevation), soil physical and chemical properties (calcium, cation exchange capacity, organic matter, clay and sand) and aEC for each date. Multivariate geostatistics, time stability analyses, and spatial regression were performed to characterize scale-dependent soil moisture patterns in space with time to determine which soil-terrain parameters influence soil moisture distribution. Results showed that soil moisture variation was time stable across the landscape and primarily associated with long-range (~250 m) soil physicochemical properties. When the soils approached field capacity, however, there was a shift in relative importance from long-range soil physicochemical properties to short-range (~70 m) terrain attributes, albeit this shift did not cause time instability. Results obtained suggest soil moisture’s interaction with soil-terrain parameters is time dependent and this dependence influences which observation scale is optimal to sample and manage soil moisture variation.
694

Addressing Public Health Risks of Persistent Pollutants Through Nutritional Modulation and Biomimetic Nanocomposite Remediation Platforms

Newsome, Bradley J 01 January 2014 (has links)
Due to their relative chemical stability and ubiquity in the environment, chlorinated organic contaminants such as polychlorinated biphenyls (PCBs) pose significant health risks and enduring remediation challenges. Engineered nanoparticles (NPs) provide a novel platform for sensing/remediation of these toxicants, in addition to the growing use of NPs in many industrial and biomedical applications, but there remains concern for their potential long-term health effects. Research highlighted herein also represents a transdisciplinary approach to address human health challenges associated with exposure to PCBs and NPs. The objectives of this dissertation research are two-fold, 1) to develop effective methods for capture/sensing and remediation of environmental toxicants, and 2) to better understand associated risks and to elucidate relevant protective mechanisms, such as lifestyle-related modulators of environmental disease. Prevalent engineered nanoparticles, including aluminum oxide and titanium dioxide, have been studied to better understand effective nanoparticle dispersion methods for in vitro nanotoxicology studies. This work has served both to effectively stabilize these nanoparticles under physiological conditions and to better understand the associated mechanisms of toxicity, which links these metal nanoparticles to endothelial oxidative stress and inflammation through phosphorylation of key cellular signaling molecules and increased DNA binding of pro-inflammatory NFκB. Surface functionalization, though, is being found to limit potential toxicity and has been utilized in subsequent research. A novel polyphenol-functionalized, NP-based system has been developed which combines the biomimetic binding capabilities of nutrient polyphenols with the separation and heating capabilities of superparamagnetic iron oxide NPs for the capture/sensing of organic contaminants in polluted water sources. Magnetic nanocomposite microparticles (MNMs) incorporating the fluorescent polyphenols quercetin and curcumin exhibit high affinity for model organic pollutants followed by rapid magnetic separation, addressing the need for sustainable pollutant remediation. Further work has been performed to both better understand health concerns associated with environmental toxicants such as PCBs and to determine effective methods for modulating their toxicity. This research has shown that PCB remediation through dechlorination is a viable technique for decreasing endothelial inflammation, although complete dechlorination to biphenyl is necessary to effectively eliminate superoxide production, NFκB activation, and induction of inflammatory markers. Additionally, the nutrient polyphenol EGCG, found in green tea, has been shown to serve as a biomedical modulator of in vivo PCB toxicity by up-regulating a battery of antioxidant enzymes transcriptionally controlled by AhR and Nrf2 proteins.
695

Water Quality Trading Markets for the Kentucky River Basin: A Point Source Profile

Childress, Ronald, Jr. 01 January 2012 (has links)
This study assessed the feasibility and suitability of a Water Quality Trading (WQT) program within the Kentucky River Basin (KRB). The study’s focal point was based on five success factors of a WQT program: environmental suitability, geospatial orientation, participant availability, regulatory incentive, and economic incentive. The study utilized these five success factors, geographical characteristics, and Discharge Monitoring Reports (DMR) to assess the feasibility of a WQT program. The assessment divided the KRB into five eight digit Hydrologic Unit Codes (HUC), North, Middle, and South Fork, Middle Basin, and Lower Basin, to determine regional impacts caused by the nutrient PSs. Individual nutrient profiles were generated to show the number of point sources (PS) operating in the KRB, their geospatial orientation to one another, and their permitted nutrient limits and nutrient discharges in form of total phosphorus (TP), total nitrogen (TN), and total nitrogen (as ammonia) (TA). Findings suggest trading is highly unlikely for TP and TN PSs due to the lack of regulatory standards, limited number of TN and TP PSs, and an inadequate demand for offset credits. Trading is also unlikely in all the HUC 8 watersheds except for the Lower Basin due to the lack of nutrient impaired waters. Key Words: Point Source, Non-Point Source, Water Quality Trading, TMDL, Impaired Waters
696

The management of potable water supply in Khuma Township, Matlosana Local Municipality / Kagisho Simon Monnahela

Monnahela, Kagisho Simon January 2014 (has links)
The birth of a non-racial democracy in South Africa brought many challenges such as the supply of potable water to all societies irrespective of their colour or even location. Migration of people from rural to urban has increased the demand of potable water supply in many areas that were previously neglected by the former Apartheid regime. The increase of the human population in urban or developing areas of South Africa will therefore imply that various public services such as potable water supply, proper housing, electricity supply, schooling and basic health facilities should be provided in an efficient, effective and economic manner. As the resident of Khuma Township, the researcher has a keen interest in the management of potable water supply in this area, inter alia, the nature and extent of the physical environment and the efficiency and effectiveness of a potable water supply as a means of improving service delivery by the Matlosana Local Municipality to Khuma Township. The area has the history of gold mining and the majority of the people from other rural areas and neighbouring states moved into this area and were later joined by their families. This resulted in an increase in the population to a point where people were placed in dangerous areas such as underlying dolomite and along the Koekemoer spruit. For example, extension 6 is known to experience sinkholes due to underground mining activities and the underline dolomite rock. The population has increased in Khuma Township to such an extent that a shortage of potable water supply is been experienced. Khuma Township had one water reservoir for the past 40 years and Matlosana Local Municipality did not improve or developed infrastructure related to potable water supply to be able to cater for the increasing population of this area. An empirical study was conducted in among the residents of Khuma Township, Matlosana Local Municipality and role-players in the management of potable water supply. From this study, it was evident that the supply of potable water in Khuma Township is insufficient, and there was poor communication, cooperation and participation between Matlosana Local Municipality and the residents of Khuma Township. The ineffective management of potable water supply in Khuma Township by the Matlosana Local Municipality as well as ignoring the significance of settling people in a safe area that is free from water pollution, sinkholes and underlying dolomite rock left a lot to be desired. The researcher arrived at logical conclusions and recommendations with regard to all aspects related to future management of potable water supply in Khuma Township. / M Development and Management, North-West University, Potchefstroom Campus, 2014
697

The management of potable water supply : the case of Mkhwanazi Tribal Authority / Magwaza, D.W.

Magwaza, Duduzile Witness January 2011 (has links)
This mini–dissertation addresses the management of the potable water supply in the Mkhwanazi Tribal Authority's area of jurisdiction. The main objectives of the study were to determine the organisational structures and public policies governing the potable water supply in the uMhlathuze Local Municipality with a view to establishing the factors that hinder the provision of potable water to some parts of the Mkhwanazi Tribal Area and also determine how the present potable water situation is perceived by the MTA residents. The Mkhwanazi Tribal Authority's area of jurisdiction is predominantly a residential area for the Zulu speaking people under the uMhlathuze Local Municipality's area of responsibility in the Province of KwaZulu–Natal. The organisational structures governing the potable water supply in the MTA identified in the study are the ULM comprising of the Municipal Council and the administrative; Integrated Development Plan; Water Services Provider; Water Committee; and the Mkhwanazi Tribal Council. The provision of potable water in the MTA is regulated through the UMhlathuze Water Services By–Laws which are based on the standards of basic water and sanitation in terms of the White Paper on Reconstruction and Development Programme (RDP) (SA, 1994:17). The study established that the challenges affecting the potable water supply are the lack of funds in the Municipality, rising water demand, human capacity and water loss. The MTA residents appreciate the current potable water supply by the ULM but have a negative attitude towards paying for water services because they consider water as a natural resource that must be freely supplied to them by the Government. Therefore, the study recommended that water awareness campaigns be conducted regularly amongst the MTA community to raise the importance of having potable water in the community. / Thesis (M. Development and Management)--North-West University, Potchefstroom Campus, 2012.
698

The management of potable water supply : the case of Mkhwanazi Tribal Authority / Magwaza, D.W.

Magwaza, Duduzile Witness January 2011 (has links)
This mini–dissertation addresses the management of the potable water supply in the Mkhwanazi Tribal Authority's area of jurisdiction. The main objectives of the study were to determine the organisational structures and public policies governing the potable water supply in the uMhlathuze Local Municipality with a view to establishing the factors that hinder the provision of potable water to some parts of the Mkhwanazi Tribal Area and also determine how the present potable water situation is perceived by the MTA residents. The Mkhwanazi Tribal Authority's area of jurisdiction is predominantly a residential area for the Zulu speaking people under the uMhlathuze Local Municipality's area of responsibility in the Province of KwaZulu–Natal. The organisational structures governing the potable water supply in the MTA identified in the study are the ULM comprising of the Municipal Council and the administrative; Integrated Development Plan; Water Services Provider; Water Committee; and the Mkhwanazi Tribal Council. The provision of potable water in the MTA is regulated through the UMhlathuze Water Services By–Laws which are based on the standards of basic water and sanitation in terms of the White Paper on Reconstruction and Development Programme (RDP) (SA, 1994:17). The study established that the challenges affecting the potable water supply are the lack of funds in the Municipality, rising water demand, human capacity and water loss. The MTA residents appreciate the current potable water supply by the ULM but have a negative attitude towards paying for water services because they consider water as a natural resource that must be freely supplied to them by the Government. Therefore, the study recommended that water awareness campaigns be conducted regularly amongst the MTA community to raise the importance of having potable water in the community. / Thesis (M. Development and Management)--North-West University, Potchefstroom Campus, 2012.
699

Urban stormwater management and erosion and sediment control an internship with the Butler Soil and Water Conservation District /

Thrash, Joel Patrick. January 2005 (has links)
Thesis (M. En.)--Miami University, Institute of Environmental Sciences, 2005. / Title from first page of PDF document. Document formatted into pages; contains [1], v, 101 p. : ill. Includes bibliographical references (p. 63-64).
700

Ανάπτυξη βάσης περιβαλλοντικής πληροφορίας για την αειφορική διαχείριση υδρολογικών λεκανών : περίπτωση Αλφειού ποταμού

Πασαπόρτη, Χρηστίνα 14 October 2013 (has links)
Έχει διαπιστωθεί ότι η διαχείριση και η προστασία των υδατικών πόρων στον ελληνικό χώρο βρίσκεται σε αρκετά πρώιμο στάδιο. Αν και η Ευρωπαϊκή Ένωση έχει εκδώσει Κοινοτικές Οδηγίες που καλύπτουν την ανάγκες ενός πλαισίου διαχείρισης αυτών από το 2000, η ένταξή τους στην ελληνική πραγματικότητα δεν έχει επιτευχθεί πλήρως μέχρι σήμερα. Ειδικότερα όσον αφορά τους υδατικούς πόρους που κατανέμονται μεταξύ δύο ή και περισσότερων διοικητικών ενοτήτων, η αειφορική διαχείριση και προστασία τους γίνεται ακόμα δυσκολότερη, καθώς στις περισσότερες των περιπτώσεων δεν είναι δυνατή η σύσταση ενιαίου φορέα διαχείρισής τους. Κρίνεται, λοιπόν, αναγκαία η συλλογή και καταγραφή των δραστηριοτήτων που φαίνεται να επηρεάζουν αρνητικά την ποιότητα των υδάτων και του γύρω περιβάλλοντος της περιοχής. Ακόμη, ιδιαίτερα βοηθητική θεωρείται η καταχώρηση αυτών σε ηλεκτρονικές βάσεις δεδομένων, ώστε να είναι ευκολότερη η συλλογική εύρεση και επεξεργασία τους. Σημαντικό μέρος των δεδομένων αυτών (π.χ. πηγές ρύπανσης) διαθέτει και χωρική πληροφορία, με συνέπεια οι βάσεις δεδομένων που θα αναπτυχθούν να ενισχύονται υποχρεωτικά με χωρικές λειτουργίες. Αυτό είναι εφικτό με τη δημιουργία χωρικών βάσεων δεδομένων, οι οποίες μπορούν να αποθηκεύουν, να διαχειρίζονται και να ανακτούν με αποτελεσματικότητα μεγάλο όγκο χωρικής πληροφορίας. Αντικείμενο της παρούσας μεταπτυχιακής εργασίας αποτελεί ο σχεδιασμός και η υλοποίηση ενός συστήματος χωρικής βάσης δεδομένων για τη λεκάνη απορροής του Αλφειού ποταμού, καθώς η συλλογή στοιχείων για τις δραστηριότητες που αναπτύσσονται γύρω από τον ποταμό ανέδειξε σημαντικά προβλήματα ρύπανσης και υποβάθμισης της ποιότητας των υδάτων της περιοχής. Επιδιώκεται η συγκέντρωση, ανάλυση και επεξεργασία όλων των χαρακτηριστικών της περιοχής που επηρεάζουν αρνητικά τους υδατικούς πόρους και το περιβάλλον αυτής, με στόχο τον υπολογισμό των ρυπαντικών φορτίων που καταλήγουν στον Αλφειό. Στα πρώτα κεφάλαια της εργασίας παρουσιάζεται το νομοθετικό πλαίσιο σχετικά με τη διαχείριση των υδατικών πόρων σε ευρωπαϊκό και εθνικό επίπεδο, καθώς και τα βασικά χαρακτηριστικά της υφιστάμενης κατάστασης της λεκάνης απορροής, τα οποία επηρεάζουν άμεσα ή έμμεσα τους υδατικούς πόρους, καθώς και ποιοι είναι αυτοί. Στη συνέχεια, πραγματοποιείται ο καθορισμός των απαιτήσεων των χρηστών και ο σχεδιασμός της βάσης δεδομένων, όπου παρατίθενται τα δεδομένα που πρόκειται να εισαχθούν στη βάση. Ακολούθως, αναλύονται οι τεχνολογίες το λογισμικό ελεύθερου και ανοιχτού κώδικα και που επιλέχθηκε για τη σύσταση της βάσης. Σε τελικό στάδιο περιγράφεται η διαδικασία υλοποίησης της βάσης και πραγματοποιείται ο υπολογισμός των ρυπαντικών φορτίων αζώτου (Ν), φωσφόρου (Ρ) και οργανικών ενώσεων μέσω της εκτέλεσης πολύπλοκων και σύνθετων ερωτημάτων επί των δεδομένων με χρήση της Γλώσσας Δομικής Αναζήτησης (SQL). / It has been established that the management and protection of water resources in Greece is at a very early stage. Even though the European Union issued EU Directives that cover the needs of such a management framework since 2000, the integration into the Greek reality has not been fully achieved so far. In particular regarding water resources allocated between two or more administrative units, the sustainable management and protection becomes even more difficult, since in most cases a single management structure is unable to be established. Therefore, the collection and recording of activities that seem to adversely affect the quality of the water and the surrounding environment of the region is necessary. Still, particularly auxiliary is the inclusion on electronic databases, so it is easier to find collective and edit them. An important part of such data (e.g. pollution sources) has spatial information, so the databases will be developed in order to be assisted with spatial functions required. This is possible by creating spatial databases that can store, manage and retrieve efficiently large volumes of spatial information. The purpose of this thesis is the design and implementation of a system of a spatial database for the catchment area of the River Alfeios (Alpheus). As the collection of data on the activities developed around the river showed, there are significant problems of pollution and degradation of water quality in the region. It is pursued the collection, analysis and processing of all the features of the area negatively affecting water resources and the environment, in order to estimate pollutant loads, resulting in Alfeios. In the first chapters of the thesis are presented the legislative framework for the management of water resources at European and national level and the basic characteristics of the existing situation in the catchment area, which directly or indirectly affect water resources and what they are. Then, take place the setting of user requirements and the design of the database, in which the data are going to be imported. Next, analyzes the technologies, as well as the free and open source software chosen for the establishment of the base. At the final stage, the implementation process of the base is described and the calculation of pollutant loads of nitrogen (n), phosphorus (p) and organic compounds through the execution of complex and compound queries on data using Structural Query Language (SQL).

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