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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.
301

Efterpolering med våtmark : Hur kan det användas vid Haga reningsverk?

Carlsen, Inger-Marie January 2015 (has links)
The aim of this report is to present a proposal for a constructed wetland as a complement toHaga treatment plants, Surahammar. First, a literature study in the subject was made andthen a case study was conducted, where Ekeby and Trosa wetland was visited. Parallel anarchival study was performed and several field visits were made to the proposed site toinvestigate the local conditions for constructing a wetland adjacent to Haga treatment plants.Finally, a proposal for the design of the constructed wetland was made. The proposalincludes an oxygenating area for reduction of ammonium to nitrate followed by a system ofdams and channels to convert nitrate to nitrogen diffuses into the air. Phosphorus removaltakes place throughout the residence time in the wetland, as well as reduction of the bacterialload. Expected results for the outgoing water from the wetland is that P-tot can be reduced to0.10-0.11 mg / l, N-tot can be reduced to 11-14 mg / l, a reduction of E. coli, fecal streptococciand intestinal streptococci by 70-99% and a little reduction of residues from drugs take placedue to oxygenation and the UV-irradiation of the water. / Allt vatten här på jorden ingår i den hydrologiska cykeln, så även det renade avloppsvattnet.Avloppsvatten innehåller bland annat kväve och fosfor vilka bidrar till övergödningen avsjöar, vattendrag och hav. Övergödningen är ett utbrett problem och i Västmanland är 53 %av länets sjöar och vattendrag utsatta för det.Syftet med den här rapporten är att ta fram ett förslag till våtmark för Haga reningsverk,Surahammar. Först har information om hur en våtmark kan användas för efterpolering avrenat avloppsvatten tagits fram för att därefter nyttjas som grund i ett förslag till våtmark förHaga reningsverk, Surahammar. Först gjordes en litteraturstudie inom ämnesområdet ochdärefter gjordes en fallstudie där Ekeby och Trosa våtmark besöktes. Parallellt utfördes enarkivstudie och flera områdesbesök på den tilltänkta platsen för att få fram vilkaförutsättningar som finns för att anlägga en våtmark i anslutning till Haga reningsverk ochsist gjordes ett förslag på en våtmark.Anledningen till att anlägga en våtmark kan vara flera, men att avskilja fosfor, kväve samtbryta ner organiskt material är vanliga orsaker. En våtmark fungerar som ett kompletterandesteg till det ordinarie reningsverket och minskar belastningen på recipienten. Hur mycketutsläppen reduceras beror på många faktorer och egenskaper där utformning, vattnetsuppehållstid, syresättning och tillgång till organiskt material är viktiga men även parametrarsom förbehandling av avloppsvattnet och belastningen på våtmarken spelar stor roll. Ävenväxtligheten i våtmarken påverkar det slutliga resultatet, både vad det gäller vad och hurmycket som avskiljs. Avskiljningen av fosfor och kväve sker främst genom sedimentation ochnäringsupptag till växter samt att kväve även avskiljs vid denitrifikation. För den långsiktigaavskiljningen av kväve från vattnets kretslopp är nitrifikation och denitrifikation de som harstörst betydelse. Nitrifikationsprocessen är när ammoniumjoner omvandlas till nitratjoneroch det kräver god tillgång på syre, därefter följer denitrifikationen när nitratjonerna undersyrefria förhållanden omvandlas till kvävgas som diffunderar upp i atmosfären. För attnitrifikationsprocessen ska kunna fungera krävs antingen att det finns ennitrifikationsanläggning i reningsverket eller en syresättningsfas i våtmarken. Det kan skapasgenom att börja våtmarken med en översilningsäng, där det renade avloppsvattnet får strilaner över en bevuxen äng. Vattnet syresätts av luften och nitrifikationsbakterier som trivs bra iväxtligheten utför nitrifikationsprocessen och omvandlar ammoniumjonerna till nitratjoner.Därefter följer ett system av dammar och kanaler där denitrifikationsprocessen tar vid ochomvandlar nitratjonerna till harmlöst kväve. Även i dammar och kanaler har växtlighetenstor betydelse eftersom det bildas biofilm, ett tunt lager av bakterier på växterna, som deltar iden biologiska processen av nedbrytning av organiskt material samt avskiljning av fosfor ochkväve i vattnet.När vattnet passerar genom våtmarken sker också en reducering av antalet bakterier somfinns i det renade avloppsvattnet. Mätningar av E. coli, fekala streptokocker, Koliformabakterier och intestinala enterokocker visar på att halterna kan reduceras kraftigt. Även vissaläkemedel visar tendenser till att brytas ned, men läkemedel är en komplex grupp och detfinns begränsad kunskap om deras omvandling och påverkan i miljön. Det finns dock indikationer om att nedbrytningen av läkemedelsrester är högre i de våtmarker som harsyresättande delar som till exempel översilningsäng.Haga reningsverk är beläget strax utanför Surahammars tätort och har idag en kulvert somleder ut det renade avloppsvattnet från verket till recipienten. Mellan Haga och recipientenligger ett markområde på cirka 750 gånger 750 meter som skulle kunna utnyttjas till envåtmark. Redan idag ligger utsläppsvärdena för Haga reningsverk under de tillåtna halternamen en önskan att ytterligare minska belastningen på miljön finns. Vid analysering avutsläppsvärden för Haga reningsverk framkom att ammoniumkväve utgör en stor andel avutgående totalkväve samt att halterna av totalfosfor, BOD7 och suspenderade ämnen är lågatill måttliga. Ett förslag på våtmark anpassat till de förutsättningar som råder vid Hagareningsverk har tagits fram och presenteras i rapporten. Våtmarken föreslås innehålla tvåsektioner med först en översilningsäng för att reducera den höga andelen ammoniumkväveoch därefter ett damm och kanalsystem för att reducera nitratkvävet. Under hela processensker avskiljning av fosfor samt reducering av bakterier och en viss nedbrytning avläkemedelsrester. Förväntade resultat för det utgående vattnet från våtmarken är att P-totkan reduceras till 0,10–0,11 mg/l, N-tot kan reduceras till 11–14 mg/l, en reducering av E.coli, fekala streptokocker och intestinala streptokocker med 70-99 % samt att en vissminskning sker av läkemedelsrester tack vare syresättning och solens UV-bestrålning avvattnet.
302

Electroplating wastewater polishing in constructed wetland systems

Sochacki, Adam 10 September 2013 (has links) (PDF)
This thesis presents various aspects of polishing the electroplating wastewater in constructed wetlands: analysis of the performance, study on the operation and configuration effects, effects of various carbon sources, analysis of the substrate (bed media), analysis of plants, and design issues.The goals of the experiment were to: (i) study the feasibility of polishing electroplating effluent, (ii) study the effect of operating schemes, plants, bed media and wastewater strength, (iii) to elucidate metal removal mechanisms in the CW microcosms.This study furnished new information and expanded the existing knowledge on industrial wastewater treatment in constructed wetlands. In fact, this is, to the best knowledge, the first publication studying the removal of metals and cyanide from electroplating wastewater in subsurface flow constructed wetlands. The aim of this study was to study the polishing of the electroplating wastewater pretreated using physical-chemical methods.
303

Vertical-flow constructed wetlands for the treatment of wastewater and stormwater from combined sewer systems

Arias Lopez, José Luis 30 September 2013 (has links) (PDF)
French vertical-flow constructed wetlands (VFCW) directly treating raw wastewater are known to perform well on for SS, COD and nitrification. They are also known to robustly cope with hydraulic overloads during rainfall events. Although numerous systems have been installed in areas equipped with a combined sewer, the limits of stormwater acceptance remain ill-defined and need to be improved. Looking at the various VFCW designs and usages reported in the literature, it is difficult to draw any consensus on their hydraulic limits. Consequently, designing VFCW to accept hydraulic overloads is a complex task, as local context strongly impacts inlet flows produced during rainfall events. Dynamic models appear a requisite for filter design in such cases. Numerical CW models have essentially focused on horizontal flow, with few attempting to study VFCW dynamics which are more commonly tackled via mechanistic models. Although mechanistic models are powerful tools for describing processes within the VFCW, they are generally too complicated to be readily used by designers. The choice between detailed description and easy handling will depend on the modelling aims. If the aim is a global design tool, simplified models offer a good alternative. However, the simplified models geared to studying VFCW dynamics are extremely reduced. They are easy-handling for design and well-adapted to specific purposes (combined sewer overflow -CSO- treatment) but not necessarily to VFCW treating combined sewer wastewater, where long-term infiltration rates vary significantly. Consequently, this PhD thesis work focused on developing a simplified hydraulic model of VFCW to guide designers through the process of adapting VFCW systems to treat domestic wastewater in both dry and rain events. The simplified model makes it possible to link (i) hydraulics, by simulation of ponding time variations, (ii) biological performances, by establishing "dysfunction alerts" based on treatment performance assessment and variations in online N forms effluent from the young VFCW. These "dysfunction alerts" plot the maximal hydraulic load that a filter can accept without compromising its biological activity. The simplified model was used to model long-term hydraulics in the VFCW (i) to analyze the impact of local context and filter design on hydraulic overload acceptance (using "dysfunction alerts" and bypass discharges) and (ii) to propose VFCW designs for accepting hydraulic overload in different contexts. The modelling demonstrates that VFCW can limit days with bypass discharges to less than 20 times per year without jeopardizing filter performances. Moreover, the most problematic scenario on stormwater treatment remains a watershed with high imperviousness coefficient and low slope under a Bretagne-type climate, demonstrating that the filter is more sensitive to periodicity and duration than to intensity of rainfall events.
304

An investigation into the technical feasibility of using vegetated submerged bed constructed wetlands for the treatment of landfill leachate.

Olufsen, Jonathan Simon. January 2003 (has links)
Landfill leachate treatment in South Africa is still in its early stages; research has been conducted but primarily at pilot scale level. Current legislation in South Africa does not prohibit the discharge of landfill leachate into the sewer line, despite the high risk of methane explosions and corrosion of the sewer pipes. Thus, to date, the off site channelling of landfill leachate into the sewer lines for further dilution in municipal wastewater treatment plants is the most common practice. Due to the development of stricter environmental regulations, the design of sustainable landfills is leading to the 'treatment at source' concept. Increasing public pressure is also forcing new landfills to be situated in remote areas where there is no avaliable sewer line to discharge into and 'treatment at source' will be required. Due to these developments, coupled with the lack of full scale leachate treatment experience in South Africa, Durban Solid Waste (The waste service unit of the Durban metropolitan), in an attempt to develop the knowledge and practical experience required for leachate treatment, undertook a research project to investigate the use of nitrification/denitrification pilot scale sequencing batch reactors (SBR) to treat leachate from the Bisasar Road and Mariannhill Landfills. The successful completion of the trials proved that the full removal of nitrogen compounds could be easily achieved, under South African climatic conditions, in a single sludge SBR system. The system was found to be simple to operate and required low maintenance. However, the final effluent required further treatment before it could meet the general discharge standards into natural watercourses. Being South Africa, a 'low gross income' country, it became necessary to consider an appropriate, cost effective and technically feasible 'polishing' treatment system. It was decided that a pilot scale treatment trial, using vegetated submerged bed constructed wetlands, be undertaken to assess the applicability and feasibility of such a passive system for the 'polishing' of the effluent from the pilot scale sequencing batch reactors. The wetland systems were found to be affected by many interrelating climatic factors. The trials concluded that the wetlands could not achieve the required discharge standards, in terms of concentration. However, it also showed that the effluent organics posed no oxygen demand or toxic threat to a receiving environment. The trials showed the ability of the wetlands to behave as mass removal systems, which could achieve the required mass removal efficiency in terms of mass output per day. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.
305

Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien : Kväve- och fosforrening i anlagda våtmarker.

Charlson, Alexandra January 2014 (has links)
A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ‘til April2014. The mean influent concentrations from wastewater directly from the factory were2,606 mg/L, 46.60 mg/L, 318.3 mg/L and 1,112 mg/L for BOD5, TP, TKN and TSS. Themean results of reduction through the wetlands gave the following results; BOD5 42 ± 351%,TP 66 ± 9.7%, TN 42 ± 13% and TS -11 ± 30%. Compared to other wetland systems treatingsimilar wastewater the reduction of BOD5 and TSS is low. Recommended solutions toincrease the reduction in the wetland are presented in the discussion. / Processvatten från livsmedelsindustrier och anläggningar med animalieproduktion har högakoncentrationer av organiskt material, suspenderat material och närsalter (Kadlec & Wallace,2008). Förr släpptes mycket processvattnet direkt ut till närliggande dammar, floder ellerbäckar. I moderna tider finns riktvärden satta från till exempel svenska Naturvårdsverket och det brasilianska miljödepartementet, CONSEMA, som gör att processvattnet måste förbehandlas innan det kan släppas till recipienten. Våtmarker har visat sig vara ett bra val av reningsmetod när det kommer till rening av bland annat kväve, fosfor, BOD5 och TSS(Camino et al., 2011; Johansson, 2014; Knight et al., 2000; Lin et al., 2005; Mantovi et al.,2003). De olika typer av anlagda våtmarker har för- och nackdelar, till exempel har vissa typer en högre nitrifikationsprocess och andra har en högre denitrifikationsprocess. Genom attkänna till vilka för- och nackdelar de olika typer av anlagda våtmarker har går det att skräddarsy ett behandlingssystem som uppfyller de specifika reningsändamålen för just det processvattnet. Syftet med detta arbete är att avgöra hur pass effektiv NaturOvos våtmarkreducerar föroreningar, att får en bättre förståelse av olika typer av anlagda våtmarker samt deras kväve- och fosforreningsprocesser. NaturOvos äggfabrik ligger i Salvador do Sul, Rio Grande do Sul, Brasilien. Under juni år 2013 byggdes en horizontal subsurface flow (HSSF) våtmark för att öka kväve- och fosforrening av processvattnet från fabriken. Behandlingssystemet består av en aktivslamanläggning bestående av två luftningsbassänger och två sedimenteringstankar, en uppehållsbassäng och en HSSF våtmark. Recipienten är en närliggande damm. Behandlingsvattnet som renas genom systemet innehåller processvatten och vatten som används vidrengöring av fabriken. Obehandlat vatten direkt från fabriken har ett medelvärde på2 606 mg/l för BOD5, 46,60 mg/l för TP, 318,3 mg/l för TKN och 1 112 mg/l för TSS. Provtagning av inflödes- och utflödesvatten har skett tre gånger per månad från oktober 2013 till april 2014. Medelvärdesresultat av retention i våtmarken är följande; BOD5 42 ± 351 %,TP 66 ± 9,7 %, TN 42 ± 13 % och TS -11 ± 30 %. Jämfört med andra studier (Camino et al.,2011; Johansson, 2014; Knight et al., 2000; Lin et al., 2005; Mantovi et al., 2003) är retentionav kväve och fosfor hög, men retentionen av BOD5 och TS är låg. Förbättringsförslag för att öka reningen i våtmarken redovisas i diskussionen.
306

Facilitating a co-constructed learning environment for caregivers in social gerontology : applying the 'Ripples on a pond' model / Magdel Fivaz

Fivaz, Francina Magdalena January 2010 (has links)
Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2010.
307

Facilitating a co-constructed learning environment for caregivers in social gerontology : applying the 'Ripples on a pond' model / Magdel Fivaz

Fivaz, Francina Magdalena January 2010 (has links)
Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2010.
308

Optimization techniques for speech emotion recognition

Sidorova, Julia 15 December 2009 (has links)
Hay tres aspectos innovadores. Primero, un algoritmo novedoso para calcular el contenido emocional de un enunciado, con un diseño mixto que emplea aprendizaje estadístico e información sintáctica. Segundo, una extensión para selección de rasgos que permite adaptar los pesos y así aumentar la flexibilidad del sistema. Tercero, una propuesta para incorporar rasgos de alto nivel al sistema. Dichos rasgos, combinados con los rasgos de bajo nivel, permiten mejorar el rendimiento del sistema. / The first contribution of this thesis is a speech emotion recognition system called the ESEDA capable of recognizing emotions in di®erent languages. The second contribution is the classifier TGI+. First objects are modeled by means of a syntactic method and then, with a statistical method the mappings of samples are classified, not their feature vectors. The TGI+ outperforms the state of the art top performer on a benchmark data set of acted emotions. The third contribution is high-level features, which are distances from a feature vector to the tree automata accepting class i, for all i in the set of class labels. The set of low-level features and the set of high-level features are concatenated and the resulting set is submitted to the feature selection procedure. Then the classification step is done in the usual way. Testing on a benchmark dataset of authentic emotions showed that this classification strategy outperforms the state of the art top performer.
309

Komponovaná krajina Františka Josefa Schlika a "krajinotvorba" kolem roku 1700 / Landscape Composition of Count Frantisek Josef Schlik and the "Landscape Creation" around the Year 1700

Rychnová, Lucie January 2016 (has links)
This thesis describes the landscape composition of Czech Count Frantisek Josef Slik (Frantz Joseph Schlik, 1656-1740) and attempts to define the influences and principles which were involved in the formation of the landscape in the manors of Kopidlno, Stare Hrady and Velis- Voksice, now in the Czech Republic, during the life of the aristocrat. Frantisek Josef Schlik ruled the manors for over 60 years and during that time he was responsible for many architectural works with considerable landscape-forming and urbanistic potential. A series of visually interlinked chapels was erected in the Velis-Voksice manor. This series included the meierhof with a little palace in Voksice. This landscape composition has been discussed especially as regards its formal design, but its connection to the Count's motivation has been less well researched, as has been the broader social and, especially, religious context in the area. Another aspect that has been put aside, or not perceived within the context of the manorial landscape, were other structures which Frantisek Josef Schlik built or which were of essential importance for the activities in the manor. These structures, meierhofs, were also significant landscape components. This dissertation first attempts to provide a biography of Frantisek Josef Schlik,...
310

Avaliação da biodegradabilidade de lixiviado de aterro sanitário consorciado com esgoto doméstico em um sistema biológico de tratamento de efluentes

Reque, Patrícia Tambosi January 2015 (has links)
O líquido denominado “lixiviado”, formado pela disposição de resíduos em aterros sanitários e lixões, apresenta composição complexa, dada principalmente pela presença de compostos orgânicos extremamente recalcitrantes. O tratamento consorciado deste efluente com esgotos domésticos em ETE’s municipais carece de estudos, tendo em vista que são líquidos com características diferentes. Neste trabalho foi avaliado o desempenho de um processo biológico de tratamento de efluentes, composto por 3 sistemas de banhados construídos (B1, B2 e B3) operados em paralelo, tratando a combinação de esgoto doméstico (90%) + lixiviado de aterro sanitário (10%), no que diz respeito a remoção de matéria orgânica de lenta degradação. Cada sistema foi composto por 4 leitos cultivados com as macrófitas emergentes Luziola peruviana e Typha latifolia, recebendo afluente proveniente de diferentes níveis de pré-tratamento, nomeadamente: B1 - processo biológico anaeróbio (UASB) seguido de aeróbio (CBR); B2 - processo biológico aneróbio (UASB) e B3 - sem prévio tratamento. Para tal, além das análises da matéria orgânica pelos parâmetros não específicos, foi também empregada análise de absorbância e fluorescência para analisar a presença de substâncias húmicas e o uso da respirometria para avaliação da DQO lentamente biodegradável. As eficiências médias de remoção dos sistemas B1, B2 e B3 foi de 97,4, 96,1 e 96,6 % para DBO5, 66,9, 70,9 e 80,6% para DQOT, 61,9, 69 e 62,8 % para DQOFil e de 60,3, 72,8 e 72 % para COT, respectivamente. A avaliação destes parâmetros permitiu inferir que o nível de pré-tratamento não influenciou na eficiência de remoção pelos sistemas de banhados. Os espectros de absorbância foram marcados por maior absorbância na região λ < 400 nm, com diminuição progressiva até 700 nm. A aplicação de coeficientes de absortividade indicaram a predominância de matéria orgânica dissolvida proveniente de esgoto doméstico, com pouca influência de SH’s. Nos espectros de emissão de fluorescência, o aparecimento de bandas na região de 450 nm indicou a presença de substâncias húmicas no afluente e efluente do sistema de banhados construídos, sem diferença significativa entre a intensidade de fluorescência emitida em 450 nm nas amostras analisadas, indicando que a substância em questão passou pelo tratamento sem ser degradada. Os resultados observados pela análise de fluorescência sincronizada do B1 apresentaram contribuição positiva do pré-tratamento (menor concentração de DQOFil) para o desempenho do banhado, devido a menor presença de ácidos húmicos no efluente. / The liquid known as "leachate", produced by the disposal of waste in landfills and dumps, has a complex composition, characterized mainly by the presence of recalcitrant organic compounds. Currently, there is a lack of knowledge regarding the co-treatment of leachate with municipal wastewater in WWTP's, considering that these are effluents with different characteristics. This study evaluated the performance of a biological treatment process of wastewater consisting of 3 constructed wetlands systems (B1, B2 and B3), operated in parallel, treating a combination of domestic sewage (90%) + landfill leachate (10 %). Each system was comprised of four beds cultured with emerging macrophytes Luziola peruviana and Typha latifolia receiving affluent from different levels of pre-treatment, namely: B1 - anaerobic biological process (UASB) followed by aerobic biological process (CBR); B2 - anaerobic biological process (UASB). B3 received the untreated effluents. The content of organic matter and humic substances was analyzed by non-specific parameters, absorbance and fluorescence methods. Respirometry test were conducted to evaluate the content of slowly biodegradable COD. The average removal efficiencies of systems B1, B2 and B3 was of 97.4, 96.1 and 96.6% for BOD5, 66.9, 70.9 and 80.6% for CODT, 61,9, 69 and 62.8% for CODFil and 60.3, 72.8 and 72% of TOC, respectively. The evaluation of these parameters allowed to infer that the level of pre-treatment did not influenced the removal efficiency by wetland systems. Absorbance spectra were marked by greater absorbance in the region λ = <400 nm with progressive decrease up to 700 nm. Absorptivity coefficients indicated the predominance of domestic sewage, with little influence of SH's. In the fluorescence emission spectra, the appearance of bands in the 450 nm region indicated the presence of humic substances in the influent and effluent of the constructed wetland systems without a significant. This indicates that the substance in question went through the treatment without being degraded. The results obtained by synchronous fluorescence analysis showed a positive contribution of the B1 pretreatment (lowest concentration DQOFil) to the observed performance due to less presence of humic acids in the effluent. The authors did not have success during evaluation of the slowly biodegradable COD using the method proposed before.

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