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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.
801

No-Fly-Region for Multicopter Applications

Pasupuleti, Richie Gabriel Martin 17 June 2016 (has links)
Now-a-days safety systems and their advanced features have become a major part of human lives. People are ready to pay accordingly for the features they get for and very enthusiastic towards technology and latest trends. One such thing is drone or multicopter. These days everybody is getting interested in drones to buy, not only the fact that it is used in various scientific ways, sports and recreation purposes but also the latest advancements that was taking place in the development of light weight flying vehicles has made many scientific researchers, multinational companies and almost all the people to turn their eye towards the development of drones. And many companies are doing research for development of new safety features which can be called as the safety for the future. Some companies already introduced drones into the market and are used in different ways for different purposes. The usage of this vehicles depends on how intelligently one uses these multicopters. This thesis introduces a feature that adds safety to the multicopters to prevent them from flying to no-fly-regions. The work in this thesis is done to provide an approach by the usage of Raspberry Pi 2 B for multicopter applications as the main development board. It also helps the multicopter to prevent entering the NFR by detecting the NFRs around them intelligently and avoid them so there shouldn\'t be any problem or damage for the multicopters. Here we use GPS sensor for getting the NMEA data as input to know the latitude and longitude positions and then transferred to RPI2 B which allows us to know the latitude and longitude positions and then transfer this data into database to store the data through a wireless medium i.e., Wi-Fi medium. Based on the information stored in database we can see the location in a graphical manner using the open street maps (OSM). After that different checks are performed to avoid the NFR : (i) We will check if the current point lies inside or outside the no-fly-region based on the map information of NFR using the Point in Polygon algorithm and then (ii) we are using some area based detection 4 algorithm to check the distance from the point to line using Paul Brouke algorithm to see how far is the next NFR from the current point and avoiding it and the information is updated and stored in the database accordingly .(iii) Later, if the multicopter is out of all no-fly-region then the distance to the next NFR or nearest ones is analyzed and the information will be used for safety purpose. By using geometry and algorithms we are checking and finding out the NFRs and avoid entering into the NFR space. If the point is detected inside a no-fly-region then the last point outside this region will be detected which is marked as safe and the multicopter will be backtracked to the previous point before entering the no-fly-region i.e., the safe point. This paper not only aims at multicopter safety but also throws light into the future systems that are going to be developed in the field of Car-2-X, ensuring extended safety of the passengers.
802

Dead Men Tell No Tales: How the British Empire Destroyed Pirates With Monstrous Legal Rhetoric

Nef, Ashley L. 11 May 2023 (has links) (PDF)
The state often enacts violence against marginalized groups by rendering them monstrous. The early eighteenth century saw early and stellar instances of this phenomenon in the way the British Empire pursued and executed pirates. These "golden age" pirates represented an extraordinary cross-section of marginalization politically, economically, socially, and otherwise, all of which threatened the political and social mores of Imperial Britain. In order to implement a policy and practice of pirate annihilation, British authorities constructed pirates as monstrous by racializing, dehumanizing, and emphasizing the supernatural quality of pirates. This study analyzes three eighteenth-century piracy trial transcripts--those of William Kidd, Stede Bonnet, and William Fly--in order to assess how lawyers and judges constructed pirates as monstrous so as to justify the massive and total violence inflicted on them as a class resulting in their complete destruction. In so doing, this study tracks rhetorical tactics and strategies still used by empires and the state today against marginalized peoples to an original historical source.
803

Fitnesskomponenter hos honor av Drosophila melanogaster : Med alternativa alleler av en potentiell sexuellt antagonistisk gen / Fitness components in female Drosophila melanogaster : With alternativ alleles of a potentially sexually antagonistic gene

Högström, Maja January 2023 (has links)
Anisogami och sexuella konflikter kan vara grunden till flera fall av könslig dimorfism. Intralokus sexuell konflikt uppstår när alleler vid ett genetiskt lokus har en antagonistisk effekt på fitness hos hanar och honor. Helgenomstudier har pekat ut flera sexuellt antagonistiska kandidatgener hos Drosophila melanogaster. En av dem, CG15170, har återskapats med hjälp av genediteringstekniken CRISPR/Cas9. Den här genen är intressant då populationer med en viss allel, A1, inte förlorar balanser kromosomen, förmodligen på grund av negativ fitnesspåverkan från den återskapade allelen A1. I den här studien undersöktes om fertiliteten hos honor och ägg-till-vuxen överlevnaden är negativt påverkad. Detta gjordes genom att antalet lagda ägg och proportionen av lagda ägg som utvecklades till vuxna individer hos honor av D. melanogaster homozygota för A1 eller A2 alleler mättes. Resultatet från de statistiska tester som utfördes visade ingen signifikant skillnad mellan honor med A1 och A2 alleler varken för antalet lagda ägg eller proportionen av ägg som utvecklades till vuxna. Däremot upptäcktes en signifikant skillnad mellan de två allelerna i antalet vuxna honor som överlevde parningen i den första delen av försöket. Denna studie kan inte påvisa att fekunditeten hos honorna och den tidiga överlevnadsgraden hos deras avkommor skulle vara olika för honor med A1 respektive A2 alleler. Det bör i stället vara någon annan del av livscykeln som påverkas av att A1 inte förlorar balanser kromosomen men vilken kan ej fastställas utifrån den här studien. / Anisogamy and sexual conflict may be the basis of several cases of sexual dimorphism. Intralocus sexual conflict occurs when alleles at a genetic locus have an antagonistic effect on the fitness of males and females. Genome wide association studies have pointed out several candidate genes for sexual antagonism in Drosophila melanogaster. One of them, CG15170, has been recreated with the gene editing technique CRISPR/Cas9. This gene is interesting because populations with one particular allele, A1, do not lose the balancer chromosome, probably because of negative effects off the allele on fitness. In this study, the fertility and egg-to-adult survival of eggs laid by females was investigated to see if these traits were adversely affected by the recreated allele A1.  This was done by measuring the number of eggs laid by females of D. melanogaster, homozygous for A1 or A2 alleles, and also by measuring the proportion of eggs that developed to adults. The results of the statistical tests that were performed showed no significant difference between females with A1 and A2 alleles, not for the number of eggs laid nor the proportion of eggs that developed into adults. However, a significant difference was detected between the two alleles in the number of adult females that survived the first courtship and mating part of the experiment. Probably some other part of the life cycle is affected by A1 not losing the balancer chromosome, but which cannot be determined by this study.
804

A SYNERGETIC APPROACH TO PRODUCE DURABLE, HIGHLY RECYCLED PAVEMENT MIXTURES

Abdalla, Ahmed, 0000-0001-5558-2405 January 2022 (has links)
Recently, Sustainable engineering has become a necessity due to the limited availability of virgin materials, environmental concerns, and the lack of economic resources. According to the United Nations, "Sustainable engineering is the process of using resources in a way that does not compromise the environment or deplete the materials for future generations." However, developing cost-efficient and long-term road infrastructure has always been a challenge. Therefore, novel solutions are required to extend the pavement life cycle and minimize raw materials utilization to overcome this challenge. This research focuses on integrating the waste material to produce rheological engineered asphalt mixtures as pavement material. This study utilized three wastes, which are Off-spec fly ash (OFA), Reclaimed Asphalt Pavement (RAP), and finally, a bio-oil extracted from Spent Coffee Ground (SCG). OFA is a viable source for recycling due to the quantities produced yearly and deposited in landfills. For many years fly ash has been effectively used as a partial replacement for Portland cement in producing different types of concrete, embankments, and soil stabilization. Most of the underutilized fly ash is Off-Spec. That was the motive behind adopting the OFA in this study. This study aims to investigate the fly ash's interaction with the asphalt binder as an additive rather than a filler. Few studies evaluated this hypothesis regarding fly ash as an additive. Moreover, this research's novelty comes as there is a lack of research evaluating the fly ash-asphalt physio-chemical interaction. RAP utilization in roads infrastructure became a current state of practice. Most state Departments of Transportation (DOTs) have been using RAP at a composition average of about 20% of the mix by mass. This study focuses on maximizing the utilization of the RAP content through using a bio-oil extracted from the SCG as a new promising rejuvenator. Spent coffee ground is not well recycled, and almost six million tons are sent to landfills every year. This waste was found to release methane into the atmosphere; methane is the second-most abundant greenhouse gas and has a global warming potential up to 86 times greater than CO2, which is highly harmful to the environment. In this study, the overreaching goal is to develop a green, innovative, and sustainable approach by recycling three different types of wastes (OFA, RAP, and SCGO) to achieve high-performance asphalt pavements. In addition, this study documents the science-based approach to successfully integrating these wastes as substitutes to the asphalt binder. Results show that some OFAs are associated with improved rheological performance, damage healing, and cracking resistance as an asphalt binder additive. The improvement is attributed to the level of interaction between the binder and the physical and chemical characteristics of the OFA. The use of rejuvenators further improved the aging resistance of the ash blends, suggesting high potential synergy, especially the proposed SCGO rejuvenator, which promotes utilizing it as a promising eco-friendly rejuvenator in the asphalt pavement industry. After engineering a product built by OFA and rejuvenators, these results have been validated by mixtures’ scale testing. 62% optimum RAP content is suggested to be utilized with an 11% dosage of the proposed SCGO rejuvenator as binder replacement. For the new engineered OFA/rejuvenators products, a 30% optimum RAP content is suggested to be used. Finally, Life Cycle Assessment (LCA) is conducted to evaluate the environmental potential of utilizing multi recycled materials in the Hot Mix Asphalt (HMA) industry. The results show a reduction in environmental impacts with RAP utilization and the new eco-friendly products (OFA and SCGO rejuvenator). Shifting HMA plant fuel to natural gas instead of Heavy Fuel Oil (HFO) offers considerable potential environmental benefits. Adopting the Ultrasonic Assisted-oil Extraction (UAE) as SCGO rejuvenator extraction method showed less energy and solvent consumption than the Soxhlet extraction, resulting in less environmental impacts. / Civil Engineering
805

Utveckling av betong för 3D-skrivare / Development of concrete for 3D-printers

Liljare, Mattias, Silveira Övrebö, Theodore January 2019 (has links)
3D-printing, också känt som additiv tillverkning, är en tillverkningsmetod som har revolutionerat många branscher och har växt stort både inom industrin och för privat användning. Tekniken använder sig utav en lager-på-lager metod för att tillverka olika objekt. Med dagens teknik går det att printa ut föremål av exempelvis metall, plast, betong och ett flertal andra material. Additiv tillverkning av betong ger möjligheten att skapa nya smarta konstruktionslösningar, vilket medför stora materialbesparingar och minskat materialspill. Produktionskostnader och hastighet kan också dra nytta av metoden genom att minska arbetskraft och eliminera kostnader för tillverkning och montering av gjutformar. Den här studien bidrar till en ökad förståelse för vad som krävs för att utveckla ett fungerande betongmaterial för additiv tillverkning. För att additiv tillverkning ska kunna standardiseras, bli mer kommersiellt och få en bredare användning krävs en djupare förståelse av betongens materialegenskaper. Detta eftersom materialet skiljer sig från konventionell betong. Syftet med detta projekt är att utveckla en betongblandning anpassad för additiv tillverkning. En undersökning görs för att hitta (i) en betongblandning med lämpliga mekaniska materialegenskaper och (ii) en betongblandning som är väl anpassad till 3Dskrivare. Det viktigaste för att en betongblandning ska kunna användas för additiv tillverkning är att blandningen kan pumpas genom systemet och extraheras genom munstycket vid tillverkning samt att slutmaterialet visar bra byggbarhet. Pumpbarhet är förutsättningen för att betongen ska kunna användas i en 3D-skrivare. Betongen ska vara tillräckligt smidig för att kunna pumpas ut genom ett munstycke, men även ha en tillräckligt god inre sammanhållning för att inte deformeras efter att den har pumpats ut. Pumpbarhet påverkas till stor del av vilken sorts pumpsystem som används. Resultaten varierar beroende på vilken pump, munstycke och slang som används vid materialtesterna. Det förefaller att en generell blandning anpassad för flera olika pumpsystem är svårt att uppnå. I det här arbetet har sex olika blandningar med olika variationer testats. Detta ledde till 38 blandningar som genomgått olika tester. De blandningarna med bäst resultat efter finjusteringar var blandning 4.1 och 5.1, de visade hög kvalité för pumpbarhet och byggbarhet. Blandning 4.1 innehåller vatten, anläggningscement, starvis 3040, glenium, CERW, krossballast och glasfibrer och blandning 5.1 är likadant fast med flygaska istället för CERW. / 3D printing, also known as additive manufacturing, is a manufacturing method that has revolutionized many industries and has grown widely both in industry and private use. The technique means using a layer-upon-layer method to manufacture different objects. With today's technology, it is possible to print objects of, for example, metal, plastic, concrete and several other materials. Additive manufacturing of concrete structures can be used to create new smart design solutions, which means significant material savings and reduced material waste. Production costs and time reduction may also be achieved using the method due to lower labor requirements and reduced costs for manufacturing and assembling of molds. This study contributes to an increased understanding of what is required to develop a functioning concrete material for additive manufacturing. In order for additive manufacturing to be standardized, become commercial and be broadly used, a deeper understanding of the concrete properties is required. This is because the material used in 3D printing differs from conventional concrete. The purpose of this project is to develop a concrete mixture adapted for additive manufacturing. A survey is made to find (i) a concrete mixture with suitable mechanical material properties, and (ii) a concrete mixture well adapted to 3D printers. The most important thing for a concrete mix to be used for additive production is that the mixture can be pumped through the system and extracted through the nozzle during manufacture and that the final material shows good buildability. Pumpability is a prerequisite for the concrete to be used in a 3D printer. The concrete must be sufficiently flexible to be pumped out through a nozzle, but also have a sufficiently good internal cohesion so as not to deform after it has been pumped out. Pumpability is largely affected by the type of pump system used. The results vary depending on the pump, nozzle and hose used in the material tests. It seems that a general mix adapted to several different pump systems is difficult to achieve. In this work, six different mixtures with different variations have been tested. This led to 38 mixtures that underwent various tests. The mixtures with the best results after fine adjustments were mix 4.1 and 5.1, they showed high quality for pumpability and buildability. Mixture 4.1 contains water, plant cement, starvis 3040, glenium, CERW, crush ballast and glass fibers and mixture 5.1 is similarly fixed with fly ash instead of CERW.
806

Nedbrytning av växtskyddsmedel i fluglarvskompostering / Fate of plant protection agents in fly larvae composting

Mattsson, Maria January 2023 (has links)
Ett av Sveriges 16 miljömål är ”Giftfri miljö”, vars målsättning är att förhindra att den biologiska mångfalden och människors hälsa hotas eller skadas genom utsläpp av kemiska ämnen i miljön. En aspekt som gör det svårt att uppnå detta miljömål är att utsläpp av potentiellt giftiga kemiska ämnen sker kontinuerligt. Lantbrukssektorn använder potentiellt giftiga ämnen för att skydda grödor och det har påvisats att flera växtskyddsmedel orsakar skador hos vattenorganismer. En källa till utsläpp inom lantbruket som inte fått stor uppmärksamhet är användning växtskyddsmedel, och sedermera hanteringen av det organiska avfallet, i växthusproduktion. Idag läggs avfallet i högar utomhus i direkt anslutning till växthusen där växtskyddsmedel riskerar att lakas ut vid regn. Mätningar gjorda i dessa högar visade att nedbrytning av de aktiva substanserna var mycket långsam, eller obefintlig.Olika behandlingsystem för bättre hantering av dessa restströmmar utvärderas och ett möjligt hanteringssystem är fluglarvskompostering. Fluglarvskompostering som avfallshanterings-system för växtrester från växthus har ännu inte utvärderats. Syftet med denna studie var att följa tio växtskyddsmedels öden vid fluglarverkompostering av växtrester från gurkproduktion, för att utröna om de aktiva substanserna återfanns i behandlingsresten (frasset), i fluglarverna eller om de bröts ned, samt om något av dessa ämnen bioackumulerades i fluglarverna. En behandling och två kontrollbehandlingar utvärderades: 1) med larver, enzymer och frass; 2) med enzymer och frass; 3) utan larver, enzymer och frass. I samtliga behandlingar analyserades koncentrationen av de aktiva substanserna innan och efter behandlingarna, samt i fluglarverna.För två växtskyddsmedel, Admiral 10 EC och Topas 100 EC, var nivåerna av de aktiva substanserna under detektionsnivån i de obehandlade växtresterna, medan den aktiva substansen i Diabolo inte bröts ner i någon av behandlingarna.De aktiva substanserna i sex växtskyddsmedel (Flexity, Floramite 240 SC, Nissorun SC, Prokinazid, Conserve och SWITCH 62,5 WG) bröts ner snabbare i fluglarvskomposteringen än i de två kontrollerna, där ingen nedbrytning skedde. De aktiva substanserna i Previcur Energy och Teppeki bröts ner i samtliga behandlingar, men nedbrytningen var något snabbare i fluglarvskomposteringen och kontroll 2, jämfört med kontroll 3.Ingen bioackumulation skedde i larverna, dock var koncentrationen av vissa aktiva substanser något högre i larvbiomassan än satt gränsvärde för nötkött, vilket skulle kunna försvåra användning av larver i djurfoder.Då de aktiva substanserna i de utvärderade växtskyddsmedlen bröts ner i högre utsträckning i fluglarvskompostering än i kontrollerna kan fluglarvskompostering anses vara en bättre hanteringsstrategi än nuvarande. Dock finns det andra försvårande omständigheter med fluglarvsbehandling av växtrester (låg effektivitet, svårt att sköra larver) som påvisar att detta inte är den mest lämpade behandlingen för denna restström. / One of Sweden's 16 environmental goals is a "Non-toxic environment” which aims at preventing biodiversity and human health from being threatened or harmed by chemical substances released into the environment. One aspect that makes it difficult to achieve this goal is that these potentially toxic substances are continuously released into the environment. Potentially toxic substances are used in agriculture to protect crops and various plant protection agents has been shown to cause damage to aquatic organisms if released into the water bodies. The use of plant protection agents in greenhouse production, as well as their handling the organic waste, has reached limited attention. Today, the waste is placed in piles outside the greenhouses, risking leaching of the plant protection agents during rainfall. Measurements in the piles showed that the degradation of plant protection agents in the piles was very slow or non-existing.To find a better solution to this problem, alternative management systems for this organic waste are being investigated. A management system being investigated is fly larvae composting, but the implementation of this treatment on plant residue from greenhouse production has to date not been investigated. The aim of this study was to investigate the fate of the active substances of ten plant protection agents during fly larvae composting, by verifying whether they would be found in the treatment residues (frass), in the fly larvae or if they would degrade. In addition, bioaccumulation of the plant protection agents in the fly larvae was investigated. One treatment and two control treatments were explored: 1) with larvae, enzymes, and frass; 2) with enzymes and frass; 3) without larvae, enzymes, and frass. The active substances in the plant protection agents were analysed before and after the treatments and in the fly larvae.For two plant protection agents, Admiral 10 EC and Topas 100 EC, the levels of the active substances were below the detection limit in the untreated plant residues, while the active substance in Diabolo was not broken down in any of the treatments.The active substances in six plant protection products (Flexity, Floramite 240 SC, Nissorun SC, Prokinazid, Conserve, and SWITCH 62.5 WG) were degraded faster in fly larva composting than in the two controls, where no degradation occurred. The active substances in Previcur Energy and Teppeki were degraded in all treatments, but the degradation was somewhat greater in the fly larvae composting and control 2, compared to control 3.No bioaccumulation occurred in the larvae, although the concentration in the larval biomass for some plant protection agents was slightly higher than the limits set for beef, which could hinder the use of larvae in animal feed.Since many plant protection agents were degraded to a greater extent in fly larva composting than in the controls, fly larva composting can be considered a better management strategy than the current one. However, other compromising factors are associated with the treatment of plant residues using fly larvae (low efficiency, difficulty in harvesting larvae) that indicate that this is not the most suitable treatment for these waste streams.
807

transgression

Reres, Shannon Elizabeth 14 December 2023 (has links)
"transgression" is a poetry collection with claws and nail polish. Across four acts, Reres uses a chorus of voices to interrogate the role of the transgressing woman—both present and past, privately and publicly. Transgressing, for Reres, is a performance. Moreover, it is a performance in which women have been asked, coerced—even forced—to participate for millenia. By stepping into the role of the transgressing woman deliberately, Reres turns this tradition on its head. In these pages, she shows that there is power in putting on masks and costumes, just as there is power in taking them off. The difference—between performance as power and performance as prison—resides in the freedom to choose. / Master of Fine Arts / "transgression" is a poetry collection.
808

Framtidens klimatvänliga bindemedel i betong : En analys av naturliga puzzolaner som tillsatsmaterial / Future climate-friendly binders in concrete : An analysis of natural pozzolans as supplementary cementitious materials

Sjödin, Sabine, Fredin, Elsa January 2023 (has links)
Betong är ett av världens mest använda byggnadsmaterial, men kan också vara en stor miljöbov. Cementklinker är en betydande beståndsdel i betong som vid tillverkning frigör stora mängder koldioxid, av den anledningen optimeras betongrecept idag genom att ersätta en del av cementen med flygaska som är en restprodukt från kolkraftsindustrin. I takt med att samhället rör sig mot en fossilfri produktion beräknas tillgången till flygaska att avta och material med liknande egenskaper undersöks som alternativa bindemedel i betong.  Syftet med studien är att, genom litteraturstudier och laboratoriska tester, undersöka huruvida naturliga puzzolaner kan ersätta mängden flygaska i en cementsammansättning utan att försämra betongens hållfasthetsegenskaper. Tryckhållfastheten samt hållfasthetsutvecklingen har undersökts hos 150x150x150 mm provkuber med varierande mängd flygaska samt vulkanaska av isländsk pimpsten respektive jordanska tuffer. Målet med studien är att minska mängden, eller helst ersätta hela andelen flygaska i en klimatförbättrad betongsammansättning.  De laboratoriska testerna har utförts enligt svensk standard där totalt 48 provkroppar gjutits. Referenskuben i undersökningen består av 80% portlandkalkstencement och 20% flygaska. Totalt har 6 olika kombinationer av provkuber gjutits där andelen flygaska ersätts med 20%, 15% eller 10% vulkanaska. Vardera provkub har utsatts för tryckhållfasthetsmätning efter 2, 7 samt 28 dygn.  Resultatet av provtryckningen visade att provkuberna innehållande isländsk pimpsten gav en ökad eller oförändrad hållfasthet vid samtliga mätningar, jämfört med referenskuben. Provkuberna innehållande jordanska tuffer medförde däremot en reducering av hållfastheten vid samtliga mätningar, jämfört med referenskuben. Provkuberna innehållande vulkanaska från isländsk pimpsten gav högst sluthållfasthet då ingen flygaska förekom i sammansättningen och något sämre värden vid inblandning av flygaska, till skillnad från provkuberna innehållande vulkanaska från jordanska tuffer som utan flygaska i princip stannade av i sin hållfasthetstillväxt efter 7 dygn. Skillnaden i resultatet mellan vulkanaska av pimpsten respektive tuffer antyder att vilken typ av material det är samt dess ursprung har betydelse för hur det presterar som bindemedel i betong. / Concrete is one of the most widely used building materials in the world, but it can also be a major environmental culprit. Cement clinker is a significant component of concrete that releases large amounts of carbon dioxide during production. For this reason, concrete recipes are now optimized by replacing some of the cement with fly ash, which is a byproduct from the coal power industry. As society moves towards fossil-free production, the availability of fly ash is expected to decrease, and materials with similar properties are being investigated as alternative binders in concrete.  The purpose of the study is to investigate, through literature review and laboratory tests, whether natural pozzolans can replace the amount of fly ash in a cement composition without deteriorating the strength properties of the concrete. The compressive strength and strength development have been studied on 150x150x150 mm test cubes with varying amounts of fly ash and volcanic ash from Icelandic pumice and Jordanian tuffs. The goal of the study is to reduce the amount, or preferably replace the entire portion, of fly ash in a climate-improved concrete composition. The laboratory tests have been performed according to Swedish standards, where a total of 48 test specimens have been cast. The reference cube in the study consists of 80% Portland limestone cement and 20% fly ash. A total of 6 different combinations of test cubes have been cast, where the proportion of fly ash is replaced with 20%, 15%, or 10% volcanic ash. Each test cube has been subjected to compressive strength measurement after 2, 7, and 28 days. The results of the compression testing showed that the test cubes containing Icelandic pumice provided increased or unchanged strength at all measurements, compared to the reference cube. However, the test cubes containing Jordanian tuffs resulted in a reduction of strength at all measurements, compared to the reference cube. The test cubes containing volcanic ash from Icelandic pumice provided the highest final strength when no fly ash was present in the composition, and slightly lower values when fly ash was added, unlike the test cubes containing volcanic ash from Jordanian tuffs which essentially plateaued in their strength development after 7 days without fly ash. The difference in results between volcanic ash from pumice and tuffs suggests that the type and origin of the material are significant factors in how they perform as a binder in concrete.
809

Symphonies of Horror: Musical Experimentation in Howard Shore's Work with David Cronenberg

Shankar, Vikram A 10 August 2017 (has links)
No description available.
810

A Poetics of Space: Opening Up a World Through Vessel Metaphors in Modern and Contemporary Poetry

Pariser, Lili 17 May 2012 (has links)
No description available.

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