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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.
31

Batch flow behandling och kontinuerligt flöde av lakvatten i en rotzonsanläggning : En jämförande studie i pilotskala / Landfill leachate treatment in batch-fed and continuous flow constructed subsurface flow wetlands : A pilot-scale comparison

Nilsson, Dan January 2010 (has links)
<p>This report deals with the performance of a batch flow treatment of landfillleachate compared with a continuous flow system. The parameters in focus were total Kjeldahl nitrogen (TKN), BOD5 and COD. The pilot-scale experiment used eight barrels with a volume of 150 liters. Each barrel was constructed differently concerning its flow, its bed material grain size and its presence of plants or not. Four of the barrels worked in batch mode, thus four in continuous flow mode. The continuous flow systems were provided with water trough small tubes with regulators. Samples were collected once a week and analysis was carried out yielding results of BOD5, COD, TKN, pH and conductivity of the effluents. The same parameters were analyzed for the influent every week. The result shows that a wetland is a good way of treating the landfill leachate as the BOD5, COD and TKN decreases. Moreover the color, which contravenes with legislative demands in the region, was distinctly decreased. Yet the report failed to show a significant difference between batch loaded and continuous flow wetlands. More studies have to be carried out in order to determine or contradict whether batch mode in fact provides a better treatment.</p>
32

Batch flow behandling och kontinuerligt flöde av lakvatten i en rotzonsanläggning : En jämförande studie i pilotskala / Landfill leachate treatment in batch-fed and continuous flow constructed subsurface flow wetlands : A pilot-scale comparison

Nilsson, Dan January 2010 (has links)
This report deals with the performance of a batch flow treatment of landfillleachate compared with a continuous flow system. The parameters in focus were total Kjeldahl nitrogen (TKN), BOD5 and COD. The pilot-scale experiment used eight barrels with a volume of 150 liters. Each barrel was constructed differently concerning its flow, its bed material grain size and its presence of plants or not. Four of the barrels worked in batch mode, thus four in continuous flow mode. The continuous flow systems were provided with water trough small tubes with regulators. Samples were collected once a week and analysis was carried out yielding results of BOD5, COD, TKN, pH and conductivity of the effluents. The same parameters were analyzed for the influent every week. The result shows that a wetland is a good way of treating the landfill leachate as the BOD5, COD and TKN decreases. Moreover the color, which contravenes with legislative demands in the region, was distinctly decreased. Yet the report failed to show a significant difference between batch loaded and continuous flow wetlands. More studies have to be carried out in order to determine or contradict whether batch mode in fact provides a better treatment.
33

Förhållandet mellan COD och TOC i skogsindustriella avlopp / The relationship between COD and TOC inforest industrial wastewater

Johanna, Frid January 2015 (has links)
Under tillverkningsprocessen i massa- och pappersindustrin bildas avloppsflöden i flera olika steg. Ett av de miljöbelastande utsläppen utgörs av organiskt material. Organiskt material kan mätas som biokemisk syreförbrukning (BOD), kemisk syreförbrukning (COD) eller som totalt organiskt kol (TOC). Analys av COD inkluderar ofta miljöfarliga ämnen (till exempel kvicksilver). Naturvårdsverket har under flera år aviserat att analysen kan komma att förbjudas och därmed blir analys av TOC allt mer vanligt. EU:s referensgränsvärden anges dock i COD och design av reningsanläggningar utgår oftast från COD. Detta leder till att båda parametrarna kommer att fortsätta att vara aktuella. Med syftet att förbättra kunskapen om sambanden mellan COD och TOC för olika typer av avlopp inom massa- och pappersindustrin samlades jämförande serier över COD och TOC in från olika svenska bruk. Serierna analyserades med hjälp av regressions- och korrelationsanalys, för att sedan jämföras med medelvärdet av brukens COD/TOC faktorer (omvandlingsfaktorer). Studien innehöll även en del där information om analyser, förbehandlingar och övergången från COD till TOC samlades in genom intervjuer med personer ute på bruken. Som en avslutande del av projektet genomfördes ett laborativt arbete i mindre skala med främsta syfte att se hur konstant omvandlingsfaktorn var över tiden. Resultaten visade att korrelationen mellan COD och TOC ofta var hög men att omvandlingsfaktorn var beroende av typ av tillverkningsprocess och rening. Värdet på omvandlingsfaktorn varierade därför mycket mellan olika bruk och delströmmar. Bruk med tillverkningsprocesser som använder få kemikalier hade en mer lika omvandlingsfaktor sinsemellan än bruk med kemikaliekrävande processer. Dessutom gav en högre reningsgrad en lägre omvandlingsfaktor. Omvandlingsfaktorn föreföll varken påverkas av halten suspenderat material eller vara årstidsberoende. Dessutomvar den också relativt konstant över tiden. / The industrial production of pulp and paper generates wastewater in several different steps in the production chain. Organic material from the wastewater will have an impacton the surrounding environment. Biological oxygen demand (BOD), chemical oxygendemand (COD) and total organic carbon (TOC) are three ways to measure organicmaterial. When analyzing COD, harmful substances such as mercury are often used. The Swedish Environmental Agency has for several years forecasted that this analysis might be banned, and therefore analysis of TOC has become more and more common in Sweden. However, COD is often used as a design parameter when designing new wastewater treatment plants and the European Union’s reference values are given as COD. Hence, both parameters will continue to be used and both need to be taken into consideration. With the aim to improve the knowledge of the relationship between COD and TOC, data series with TOC and COD were collected. The data originated from several different Swedish pulp and paper mills, as well as from different types of waste water streams within each mill. The data series were analyzed using linear regression and correlation analysis, and then compared with the companies’ mean value of the ratio between COD and TOC (the conversion factor). Information about the shift from COD to TOC, and the analyzing methods and pretreatment methods was gathered by conducting interviews with employees at the different mills. The final part of the project was a laboratory study, with the main focus to examine if the conversion factor changed over time. The results showed that the correlation between COD and TOC often was high, but that the conversion factor depended on type of manufacturing process and waste water treatment. Mills with a low use of chemicals had a more similar conversion factor than mills with a more chemical demanding process. Furthermore, a high degree of purification resulted in a lower conversion factor. The conversion factor did not seem to depend on neither the content of suspended solids nor the time of the year. Additionally, the conversion factor was relatively constant over time.
34

Öljyllä ja raskasmetalleilla pilaantuneita maita koskevan ympäristölainsäädännön ja lupamenettelyn edistäminen kemiallisella tutkimuksella

Kaakinen, J. (Juhani) 05 April 2016 (has links)
Abstract Industrial emissions and soil pollution caused by harmful substances attracted an increased public awareness in the 1970s. Ministry of the Environment contributed to the rapid development of environmental legislation. Development of Finnish environmental legislation has also been significantly affected by the membership of the EU has been in 1995. Finnish legislation is largely based on EU legislation, but in some cases it includes even stricter standards and limits than those applied on the EU level. Studies of contaminated soils in Finland began with mapping of landfills in the 1980s. The clearing and renovation project of contaminated soils named SAMASE started in 1988, and approximately 10,400 contaminated areas were surveyed. Currently, the total number of objects has already expanded to about 25,000. This thesis consists of five scientific publications related to contaminated sites. Its summary deals with environmental legislation, treatment methods for soils contaminated with oils and heavy metals, and risk assessment in general. The scientific publications focus on the utilization of two chemical methods, i.e. oil biodegradation of contaminated soil studied, especially by manometric respirometric BOD Oxitop method, and the study of railway ballast using five-step sequential extraction method. The results show that the biodegradability of oil is strongly dependent on the soil matrix and the studied oils (motor and light fuel oils), which are biodegradable well under suitable conditions. When a 6-month long biodegradation study of light fuel contamination in mineral-rich soil without soil conditioning was performed, the final biodegradation degree was surprisingly almost complete (> 90 %), in contrary to the general assumption. Thus, the inherent biodegradability is a cost-efficient and a recommended treatment method for oil contaminated soils, especially in sparsely populated areas. Research of the railway ballast showed that the multi-step sequential extraction will provide valuable information about the effects of environmental circumstances on metals bioavailability or solubility for the purposes of risk assessment. This information is necessary to understand the actual environmental risks of metals in different natural environments, thus contributing to the development of licensing procedure. The results of this thesis also show that licensing related to the restoration of contaminated soils r (authority and control procedures) must be simplified. The authorities should also have sufficient chemical knowledge, since after all, environmental problems are mainly of chemical nature. / Tiivistelmä Huoli ympäristöstä nosti 1970-luvun alussa erilaiset päästöt päivänvaloon, ja haitallisten aineiden aiheuttama maaperän pilaantuminen nousi esille 1980-luvulla. Suomeen vuonna 1983 perustettu ympäristöministeriö on edesauttanut nopeaa ympäristölainsäädännön kehittymistä. Kehitykseen on vaikuttanut merkittävästi myös EU-jäsenyytemme vuodesta 1995 lähtien ja jäsenyyden myötä implementoitu EY:n lainsäädäntö. Joiltain osin säädöksemme ovat jopa tiukempia kuin EU:n vastaavat säännökset. Suomessa pilaantuneiden maiden selvitystyö alkoi kaatopaikkojen kartoituksella 1980-luvulla. Valtioneuvoston v. 1988 antaman selonteon pohjalta käynnistyi saastuneiden maa-alueiden selvitys- ja kunnostusprojekti (SAMASE), jossa kartoitettiin noin 10 400 pilaantuneeksi epäiltyä tai todettua aluetta. Tätä työtä jatketaan edelleen viranomaisten tavanomaisen lupa- ja valvontatyön ohessa. Tällä hetkellä kohteiden kokonaismäärä on noin 25 000. Tämä pilaantuneisiin maihin (PIMA) liittyvä väitöskirjatutkimus koostuu yhteenveto-osasta, jossa käsitellään alan lainsäädäntöä, käsittelymenetelmiä ja riskinarviointia yleisesti sekä viidestä osajulkaisusta, jotka keskittyvät öljyllä pilaantuneiden maiden biohajoavuuteen manometrista respirometrista BOD Oxitop -menetelmää käyttäen ja kaivosteollisuuden sivukiven (raidesepeli) raskasmetallien analytiikkaan sekventiaalista uuttoa hyödyntäen. Tutkimuksen tulokset osoittavat, että öljy biohajoaa maassa sopivissa olosuhteissa hyvin ja luontainen biohajoavuus on täten yksi käyttökelpoinen öljyllä pilaantuneiden maiden puhdistusmenetelmä. Raidesepelitutkimukset osoittivat, että monivaiheinen sekventiaalinen uutto tuo uutta arvokasta tietoa olosuhteiden vaikutuksista metallien biosaatavuudesta/liukoisuudesta niiden riskinarviointia varten. Tämä tieto on välttämätöntä, kun halutaan ymmärtää metallien todelliset ympäristövaikutukset erilaisissa luonnonolosuhteissa ja näin edistää osaltaan lupamenettelyn kehittämistä. Väitöskirjassa todetaan myös, että pilaantuneen maan kunnostuksiin liittyen viranomaisten lupa- ja valvontamenettelyä tulee yksinkertaistaa ja viranomaisilla tulisi olla riittävästi kemian tietämystä ja kemiallista ajattelua, ovathan ympäristöongelmat pääosin luonteeltaan kemiallisia.
35

Podobnost obrazů na základě bodů zájmu / Image similarity measurement using points of interest

Jelínek, Ondřej January 2015 (has links)
This paper presents a new object detection method. The method is based on keypoints analysis and their parameters. Computed parameters are used for building a decision model using machine learning methods. The model is able to detect object in the picture based on input data and compares its similarity to the chosen example. The new method is described in detail, its accuracy is evaluated and this accuracy is compared to other existing detectors. The new method’s detection ability is by more than 40% better than detection ability of detectors like SURF. In order to understand the object detection this paper describes the process step by step including popular algorithms designed for specific roles in each step.
36

Ultrfiltry a nezávislé sytémy / Ultrafilters and independent systems

Verner, Jonathan January 2011 (has links)
This work presents an overview of several different methods for construct- ing ultrafilters. The first part contains constructions not needing additional assumptions beyond the usual axioms of Set Theory. K. Kunen's method using independent systems for constructing weak P-points is presented. This is followed by a presentation of its application in topology (the proof of the existence of sixteen topological types due to J. van Mill). Finally a new con- struction due to the author is presented together with a proof of his result, the existence of a seventeenth topological type: ω∗ contains a point which is discretely untouchable, is a limit point of a countable set and the countable sets having it as its limit point form a filter. The second part looks at constructions which use additional combina- torial axioms and/or forcing. J. Ketonen's construction of a P-point and A. R. D. Mathias's construction of a Q-point are presented in the first two sections. The next sections concentrate on strong P-points introduced by C. Laflamme. The first of these contains a proof of a new characterization theorem due jointly to the author, A. Blass and M. Hrušák: An ultrafilter is Canjar if and only if it is a strong P-point. A new proof of Canjar's the- orem on the existence of non-dominating filters (Canjar filters) which uses...
37

Exploring the effect of functional group introduction on the photoswitching ability of a bicyclo-[2.2.2]-octa-2,5-diene : A Density Functional Theory computational study of a bicyclo-[2.2.2]-octa-2,5-diene’s storage energy and thermal back conversion energy. / Att utforska effekten av introduktion av funktionell grupp på fotoväxlingsförmågan av en bicyklisk-[2.2.2]-okta-2,5-dien

Mossberg, Emil January 2023 (has links)
A bicyclo-[2.2.2]-octa-2,5-diene (BOD) is a molecular photoswitch which makes up a so-called molecular solar thermal energy storage system. A molecular photoswitch has the ability to capture, store and release solar energy as heat. These processes can be enhanced by functional groups introduction. In this thesis, the effect of functional group introductions on the BODs' solar energy storage capacity and the thermal activation energy required for energy release was investigated. Various functional groups were introduced onto the BOD, and the corresponding storage and thermal back conversion energies were computed. Correlations were identified, and further tested using a practical BOD and its related structures. Conclusively, it was revealed that a storage energy might relate to (i) an electron withdrawing functional group strength, and (ii) an electron rich atom placed next to an electron withdrawing group. A dimethyl introduced bridge was observed to reduce storage energy and seemed to have a positive effect on the thermal back conversion barrier energy. The practical BOD λmax calculation was also computed, however, the result was not so promising as expected. Very little could be said about the thermal back conversion barrier energy due to long computational time and unreliable data. / En bicyklisk-[2.2.2]-okta-2,5-dien (BOD) är en molekylär fotoväxlare som ingår i ett så-kallat molekylär sol-termisk energilagrings-system. En molekylär fotoväxlare kan fånga, lagra och släppa tillbaka solenergin i form av värme. Dessa processer kan förstärkas av funktionella gruppers introduktion. I den här kandidatuppsatsen utforskades effekten av introduktion av funktionella grupper på BODs solenergilagrings-kapacitet och den termiska aktiveringsenergin som behövs för energiutlösning.  Olika funktionella grupper introducerades på BODn, och korresponderande lagringsenergier och termiska tillbakaomvandlingsenergier beräknades. Korrelationer identifierades och testades extensivt mot en praktisk BODs och dess relaterade strukturer. Sammanfattningsvis identifierades lagringsenergins möjliga relationer till (i) en elektron-accepterande funktionell grupps stryka, och (ii) en elektron-rik atom placerade nära en elektrondragande grupp. En dimetyl introducerad bro verkade reducera lagringsenergin och positivt påverka den termiska tillbakaomvandlingsenergin. Beräkning av den praktiska BODns λmax gjordes också, men resultatet var inte det förväntade. Mycket begränsade slutsatser kunde dras om den termiska tillbakaomvandlingsenergin på grund av lång beräkningstid och opålitliga data.
38

Flygplansavisningens miljöpåverkan vid svenska flygplatser / The environmental Impact of Aircraft De-icing at Swedish Airports

Marklund, Lars January 2004 (has links)
<p>The aim of this thesis was to answer a number of questions about the environmental consequences of aircraft de-icing. A further aim was to suggest how the environmental consequences due to the release of de-icing fluids can be measured and reduced.</p><p>The main impact of the aircraft de-icing on the environment is due to the large oxygen demand for the degradation of glycol based de-icing fluids which are released in the environment. The effect of the increase in oxygen demand depends on where the degradation occurs in the ecosystem. In a sensitive ecosystem, the large demand of oxygen could provide an anaerobic environment which would be harmful for many types of organisms.</p><p>In order to reduce the negative effects of the applied de-icing fluid, there is some type of collection system at every regular airport in Sweden. The methods of collection can be divided into two general groups, hydrological isolation or vacuum sweeper trucks. When the area used for hydrological isolation is relatively small it is called a central de-icing pad. This thesis investigates which methods are being used at 16 of the Swedish airports with the most intense de-icing activity. Of all of these airports, only one does not use vacuum sweeper trucks. Six of the airports use central de-icing pads and five use hydrological isolation of a larger area. The investigation of the efficiency of each method showed no significant differences. This is due to the lack of accurate measurements and that different measurement methods are employed at different airports.</p><p>This thesis also examines which methods for measuring the efficiency are being used, their weaknesses and what alternatives methods are available. Suggestions are also given to minimize the environmental consequences of aircraft de-icing, taken into account both leakage of the de-icing fluid and its judicious use.</p><p>The case study of Stockholm-Bromma Airport includes a more detailed investigation of the de-icing activities and a rough mass balance is established. The aim of establisheing the mass balance is to determine the extent of collection of the de-icing fluids, their runoff to the storm water system or arrival at a diffuse sink. The results show that even if the collection is low, only a small part of the de-icing fluids reaches the storm water system. A relatively large part goes to the diffuse sinks where the de-icing fluids degrade on the soil surface or percolate into the soil. In the case study there is also an investigation of the probable impacts on the surrounding environment due to aircraft de-icing at Stockholm-Bromma Airport and suggestions are made how to reduce the impact.</p> / <p>Det primära syftet med examensarbetet har varit att besvara ett antal frågeställningar om flygplansavisningens miljöpåverkan. Frågeställningar som behandlar hur flygplansavisningens miljöpåverkan kan uppskattas/mätas samt reduceras.</p><p>Den miljöpåverkan flygplansavisningen ger upphov till består främst av den syreförbrukning som orsakas vid nedbrytningen av den använda, glykolbaserade avisningsvätskan. Hur stor denna miljöbelastning blir beror till stor del av var nedbrytningen äger rum. I känsliga ekosystem ger syreförbrukningen upphov till syrefattiga miljöer vilket många organismer missgynnas av.</p><p>För att reducera de negativa effekter som använd avisningsvätska kan ge upphov till sker på alla svenska reguljära flygplatser ett tillvaratagande av den använda avisningsvätskan. Uppsamlingsmetoderna som används kan uppdelas i två huvudprinciper. Den ena är att området där avisning sker begränsas hydrologiskt och den andra metoden är uppsamling med ”vakuum-sugbil”. Den hydrologiska avgränsningen kan göras för ett mindre område och benämns då som en stationär avisningsyta. Examensarbetet utreder vilka uppsamlingsmetoder för avisningsvätska som används på 16 av de svenska flygplatserna med mest avisningsaktivitet. Vid de undersökta flygplatserna används ”vakuum-sugbil” på alla utom en. På sex av flygplatserna används stationära avisningsplatser och större avgränsade områden för uppsamling finns vid fem flygplatser. Ingen signifikant skillnad i effektivitet (uppsamlingsgrad) kunde påvisas mellan de olika uppsamlingsmetoderna. Anledningen till detta kan ligga i att mätmetoderna skiljer sig mellan de olika flygplatserna och att det är mycket svårt att mäta eller uppskatta effektiviteten.</p><p>Examensarbetet utreder även vilka mätmetoder som används, deras svagheter samt alternativ till dessa. Förslag ges även till allmänna åtgärder för att minimera flygplansavisningens miljöpåverkan ur såväl utsläppssynpunkt som för resursåtgång.</p><p>En fallstudie av Stockholm-Bromma flygplats ger en betydligt djupare utredning än för övriga flygplatser och en grov massbalans upprättas för den använda glykolen. Massbalansen upprättas för man ska kunna avgöra hur stora mängder av den använda avisningsvätskan som samlas upp, lämnar flygplatsen via dagvattennätet eller når diffusa sänkor. Resultaten visar att även om uppsamlingsgraden är liten är belastningen på dagvattennätet ringa. En stor andel når de s.k. diffusa sänkorna och bryts ner på markytan eller perkolerar ner genom marken.</p><p>I fallstudien utreds även den troliga påverkan på vattenrecipienter och omkringliggande närmiljö. Förslag ges även på hur man på bästa sätt skall reducera den miljöpåverkan som den använda avisningsvätskan ger upphov till.</p>
39

Aritmetická úplnost logiky R / Arithmetical completeness of the logic R

Holík, Lukáš January 2014 (has links)
The aim of this work is to use contemporary notation to build theory of Rosser logic, explain in detail its relation to Peano arithmetic, show its Kripke semantics and finally using plural self-reference show the proof of arithmetical completeness. In the last chapter we show some of the properties of Rosser sentences. Powered by TCPDF (www.tcpdf.org)
40

Automatizovaná tvorba a kartografická generalizace kótovaných bodů z digitálních modelů reliéfu / Automatic Detection and Cartographic Generalization of Spot Heights from Digital Terrain Models

Polášek, Petr January 2015 (has links)
The aim of this work is to design automatic detection of spot heights from airborne laser scanning data and its generalization. The first part is about the idea of spot height: the importance of spot heights for altimetry representation on maps and suggestions concerning the scatter of spot heights on maps. In the following part, different approaches for terrain critical points extraction (peaks, depressions, passes) from digital terrain models are described as suitable places for spot heights location. Further, we introduce a description of geomorphological characteristics of these points by which is possible to identify its significance and generalize them. In accordance to analysis of Základní mapa ČR and recommendation for spot heights location described in literature we designed own method of automatic generation and generalization spot heights from digital terrain models. This method were implemented and there is a description of the test data and results on the real data DMR 5G of the algorithm in the end of the work. Powered by TCPDF (www.tcpdf.org)

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