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Translocation de biopolymères à travers des pores naturels ou artificiels / Translocation of biopolymers through biological or artificial nanoporesAuger, Thomas 31 October 2016 (has links)
La translocation de biopolymères à travers un nanopore intervient dans de nombreux processus biologiques et technologiques, comme le transport nucléocytoplasmique dans le pore nucléaire des cellules eucaryotes, la sécrétion de protéines, le séquençage rapide de l’ADN ou l’électrophorèse capillaire.Nous proposons une technique optique en molécule unique originale pour l’étude de la translocation de biopolymères à travers un nanopore basée sur l’effet Zero-Mode Waveguide. Nous nous sommes intéressés au passage d’ADN double-brin de plusieurs tailles, d’ADN simple-brin et d’ARN, entraînés par un flux à travers une membrane nanoporeuse track-etched. Nous montrons qu’il existe un flux critique régissant le passage des biopolymères indépendant du rayon des pores ainsi que de la taille des biopolymères et de leur nature, conformément aux prédictions théoriques de Brochard et de Gennes.Le pore nucléaire est un nanopore biologique responsable du transport sélectif entre le noyau et lecytoplasme des cellules. Nous avons étudié l’influence de la concentration en importinBeta1 – une protéine nécessaire au transport nucléocytoplasmique – sur l’organisation du canal central du pore nucléaire deXenopus laevis en mesurant la diffusion de molécules de Dextran fluorescentes à travers celui-ci. Nous observons une ouverture du canal central à basse concentration suivi d’un rétrécissement de celui-ci à plus forte concentration. Cette évolution du rayon du canal central avec la concentration en importin Beta1est conforme aux modèles en champ moyen de Opferman et coll. et de Ando et coll. et aux observations expérimentales sur des systèmes reconstitués in vitro de Lim et coll. et Zahn et coll. / The translocation of biopolymers through a nanopore is a feature common to many biological andtechnological processes such as the nucleocytoplasmic transport through the nuclear pore complex(NPC), protein secretion, fast DNA sequencing or capillary electrophoresis.We have developed an original single molecule optical detection technique for the study of biopolymerstranslocation through a nanopore based on the Zero-Mode Waveguide effect. We studied thepassage of double stranded DNA of different sizes, of single stranded DNA and of double-stranded RNAdriven by a flux through track-etched nanoporous membranes. We demonstrate that translocation isgoverned by a critical flux independent of both biopolymer size and nature and of the pore radius inagreement with the theoretical predictions of Brochard and de Gennes.The NPC is a biological nanopore responsible for the selective transport between cytoplasm andnucleus in cells. We studied the influence of importinBeta1 concentration – a protein involved in the nucleocytoplasmictransport – on the structure of the central channel of the NPC of Xenopus laevis byassessing the diffusion of fluorescently labeled Dextran molecules through the NPC. We observe anopening of the central channel at low concentration followed by a shrinking at higher concentrationin importinBeta1 in agreement with mean-field models from Opferman et al. and Ando et al. and withexperiments on biomimetic in vitro systems from Lim et al. and Zahn et al.
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[en] DISCUSSION OF THE POSSIBILITIES TO ACHIEVE A NEARLY ZERO ENERGY BUILDING (NZEB) USING THE BIM APPROACH / [pt] DISCUSSÃO DAS POSSIBILIDADES DE OBTENÇÃO DE UM EDIFÍCIO COM BALANÇO DE ENERGIA PRÓXIMO A ZERO (NZEB) USANDO A ABORDAGEM BIMALEXANDRE SANTANA CRUZ 28 December 2020 (has links)
[pt] Uma arquitetura que exige uma enorme demanda de energia contraria o conceito de um Edifício de Energia Quase Zero (em inglês Nearly Zero Energy Building - NZEB). Pesquisas indicam que edifícios de alto desempenho podem ser alcançados com um design integrado que combina estratégias de eficiência energética, como vidro de alto desempenho, com energia fotovoltaica. A metodologia BIM pode incorporar a Análise de Desempenho do Edifício para apoiar a tomada de decisão de um projeto integrado, essa abordagem é considerada essencial para alcançar um NZEB bem-sucedido. A presente investigação inclui uma revisão sistemática da literatura que orientou a pesquisa. Com base na SLR, foi desenvolvido um Manual de Entrega de Informações que propõe um novo fluxo de trabalho no qual os estudos de energia são realizados nos estágios iniciais do design para alcançar projetos com maior eficiência energética e aproveitar a colaboração intrínseca à metodologia BIM. Por fim, é apresentado um experimento hipotético de um edifício comercial para ilustrar o fluxo de trabalho proposto no IDM desenvolvido. O software Autodesk Revit foi usado para modelar o edifício e a simulação energética foi realizada no software DesignBuilder. Verificou-se que, para que esses dois softwares fossem interoperáveis, o modelo precisava ser exportado do Revit no formato gbXML. As opções de design foram baseadas na proporção de janela/parede (30 por cento, 50 por cento e 100 por cento), no vidro adotado e no sistema fotovoltaico. A análise de viabilidade econômica foi realizada com base no Valor Presente Líquido e na Taxa Interna de Retorno. Os resultados indicaram que o uso da fachada norte para produção fotovoltaica combinado com o sistema fotovoltaico da cobertura forneceu um balanço de energia próximo de zero na maioria dos casos. Por fim, todos os casos analisados têm um tempo de retorno de investimento inferior a garantia do fabricante dos módulos fotovoltaicos (25 anos), exceto no caso com 100 por cento de relação janela/parede e vidro PV na fachada norte. / [en] An architecture that requires a huge energy demand goes against the concept of a Nearly Zero Energy Building (NZEB). Research on the subject indicates that high performing buildings can be achieved with an integrated design that combines energy efficiency strategies, such as high performing glass, with photovoltaic energy (PV). The Building Information Modeling (BIM) methodology can incorporate Building Performance (BP) analysis to support decision making of an integrated design, which is considered essential to achieve a successful NZEB. The present investigation includes a Systematic Literature Review (SLR) that guided the research. Based on the SLR, an Information Delivery Manual was developed that propose a new workflow in which the energy studies are performed in the early stages of design to achieve more energy efficient projects and take advantage of the collaboration intrinsic to the BIM methodology. Lastly, a hypothetical experiment of a commercial building is presented to illustrate the workflow proposed in the developed IDM. The Autodesk Revit software was used to model the building and the energy computer simulation was performed in the DesignBuilder software. It was found that for these two software tools to be interoperable, the model had to be exported from Revit in gbXML format. The design options in the experiment were based on window-to-wall ratio (30 per cent, 50 per cent and 100 per cent), on the adopted glass, and on the photovoltaic system. The economic feasibility analysis was performed based in the Net Present Value (NPV) and the Internal Rate of Return (IRR). The results indicated that the use of the north facade for PV production combining with the PV roof system provided a nearly zero energy balance in most of the cases. Finally, all cases analyzed had a payback time of less than the PV module manufacturer guarantee (25 years), except for the case with 100 per cent window-to-wall ratio and PV Glass in the north facade.
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[en] INTERMITTENT DEMAND FORECASTING IN RETAIL: APPLICATIONS OF THE GAS FRAMEWORK / [pt] PREVISÃO DE DEMANDA INTERMITENTE NO VAREJO: APLICAÇÕES DO FRAMEWORK GASRODRIGO SARLO ANTONIO FILHO 29 September 2021 (has links)
[pt] Demanda intermitente é definida por períodos de vendas nulas intercaladas com vendas positivas e de quantidade altamente variável. A maior parte das unidades de manutenção de estoque (stock keeping units, em inglês) ao nível loja pode ser caracterizada como contendo demanda desse tipo. Assim,
modelos acurados para prever séries com demanda intermitente trazem grandes impactos em relação à gestão de estoque. Nesta dissertação nós propomos o uso do framework GAS com as distribuições adequadas para dados de contagem, além de suas versões com excesso de zeros, e aplicamos os modelos
derivados a dados reais obtidos com uma grande rede varejista brasileira. Nós demonstramos que os modelos com excesso de zeros propostos são estimados de forma consistente por máxima verossimilhança e a distribuição dos estimadores é assintóticamente normal. A performance dos modelos propostos é comparada com benchmarks adequados das literaturas de séries temporais para dados de contagem e previsão de demanda intermitente. A avaliação das previsões é feita com base tanto na precisão da distribuição preditiva quanto na precisão das previsões pontuais. Nossos resultados mostram que os modelos propostos, em especial o modelo derivado sob distribuição hurdle Poisson, performam melhor
do que os benchmarks analisados. / [en] Intermittent demand is defined by periods of zero sales interleaved with positive sales with highly variable quantities. Most stock keeping units at the store level can be characterized as containing such demand. Thus, accurate models for predicting series with intermittent demand have major impacts in relation to inventory management. In this dissertation we propose the use of the GAS framework with the appropriate distributions for count data, in addition to their versions with excess of zeroes, and apply the derived models to real data obtained from a large Brazilian retail chain. We demonstrate that the proposed models with excess of zeros are consistently estimated via maximum likelihood and the distribution of the estimator is asymptotically normal. The performance of the proposed models is compared to adequate
benchmarks from the time series literature for count data and intermittent demand forecast. Forecasting is evaluated based on the accuracy of both the entire predictive distribution and point forecasts. Our results show that the proposed models, specially the one derived from hurdle Poisson distribution, perform better than the analyzed benchmarks.
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Methods for data and user efficient annotation for multi-label topic classification / Effektiva annoteringsmetoder för klassificering med multipla klasserMiszkurka, Agnieszka January 2022 (has links)
Machine Learning models trained using supervised learning can achieve great results when a sufficient amount of labeled data is used. However, the annotation process is a costly and time-consuming task. There are many methods devised to make the annotation pipeline more user and data efficient. This thesis explores techniques from Active Learning, Zero-shot Learning, Data Augmentation domains as well as pre-annotation with revision in the context of multi-label classification. Active ’Learnings goal is to choose the most informative samples for labeling. As an Active Learning state-of-the-art technique Contrastive Active Learning was adapted to a multi-label case. Once there is some labeled data, we can augment samples to make the dataset more diverse. English-German-English Backtranslation was used to perform Data Augmentation. Zero-shot learning is a setup in which a Machine Learning model can make predictions for classes it was not trained to predict. Zero-shot via Textual Entailment was leveraged in this study and its usefulness for pre-annotation with revision was reported. The results on the Reviews of Electric Vehicle Charging Stations dataset show that it may be beneficial to use Active Learning and Data Augmentation in the annotation pipeline. Active Learning methods such as Contrastive Active Learning can identify samples belonging to the rarest classes while Data Augmentation via Backtranslation can improve performance especially when little training data is available. The results for Zero-shot Learning via Textual Entailment experiments show that this technique is not suitable for the production environment. / Klassificeringsmodeller som tränas med övervakad inlärning kan uppnå goda resultat när en tillräcklig mängd annoterad data används. Annoteringsprocessen är dock en kostsam och tidskrävande uppgift. Det finns många metoder utarbetade för att göra annoteringspipelinen mer användar- och dataeffektiv. Detta examensarbete utforskar tekniker från områdena Active Learning, Zero-shot Learning, Data Augmentation, samt pre-annotering, där annoterarens roll är att verifiera eller revidera en klass föreslagen av systemet. Målet med Active Learning är att välja de mest informativa datapunkterna för annotering. Contrastive Active Learning utökades till fallet där en datapunkt kan tillhöra flera klasser. Om det redan finns några annoterade data kan vi utöka datamängden med artificiella datapunkter, med syfte att göra datasetet mer mångsidigt. Engelsk-Tysk-Engelsk översättning användes för att konstruera sådana artificiella datapunkter. Zero-shot-inlärning är en teknik i vilken en maskininlärningsmodell kan göra förutsägelser för klasser som den inte var tränad att förutsäga. Zero-shot via Textual Entailment utnyttjades i denna studie för att utöka datamängden med artificiella datapunkter. Resultat från datamängden “Reviews of Electric Vehicle Charging ”Stations visar att det kan vara fördelaktigt att använda Active Learning och Data Augmentation i annoteringspipelinen. Active Learning-metoder som Contrastive Active Learning kan identifiera datapunkter som tillhör de mest sällsynta klasserna, medan Data Augmentation via Backtranslation kan förbättra klassificerarens prestanda, särskilt när få träningsdata finns tillgänglig. Resultaten för Zero-shot Learning visar att denna teknik inte är lämplig för en produktionsmiljö.
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Design Guidelines of A Low Power Communication Protocol for Zero Energy DevicesZhang, Jiayue January 2023 (has links)
Lågströmskommunikationsprotokoll såsom 6LoWPAN har använts i stor utsträckning för applikationer som kräver mindre energiförbrukning för trådlös kommunikation på korta avstånd, exempelvis IoT-enheter. Eftersom antalet sådana enheter ökar blir det allt viktigare att överväga ambient energy harvesting som en energikälla för att driva sådana enheter. Det framkallar ett behov av att ompröva designen av ett energieffektivt kommunikationsprotokoll som gör det möjligt för sensorer och aktuatorer att använda den utvunna energin för beräkning och kommunikation. Eftersom den utvunna energin från en energikälla är begränsad och det tar tid för en enhet att samla tillräckligt med energi för datahantering och kommunikation, finns det ett behov av att undersöka energibudgeten och bestämma de kritiska parametrarna som påverkar energiförbrukningen för trådlös kommunikation. En analys av energiförbrukningen utfördes genom att anpassa en Python-modell och simuleringar genomfördes för att hjälpa till att förstå påverkan av nyckelparametrar på energiförbrukningen med hänsyn till en lämplig radio frequency energy harvesting (RF-EH) för “zero” energienheter. I examensarbetet föreslås designöverväganden för ett nytt lågströmskommunikationsprotokoll för “zero” energienheter. Resultaten visade att adaptive data rate (ADR) har en stor betydelse för energibesparingar. Med lämpliga överföringsparametrar inställda kan energiförlusterna för omsändningar och kollisioner minskas. Det är också möjligt att införa en schemaläggningsalgoritm för kommunikationsprocessen för förbättrad kollisionsundvikande. De föreslagna designövervägandena kan tillämpas i framtida arbeten för att förbättra kortdistanskommunikationsprotokollet för “zero” energienheter. / Low power communication protocols such as 6LoWPAN have been widely used on applications that require less energy consumption for short-range wireless communication, for example, Internet of Thing (IoT) devices. As the amount of these devices escalates, it becomes increasingly important to consider ambient energy harvesting (EH) as an energy source to power such devices. This induces a need to reconsider the design of an energy-efficient data transfer protocol that enables the sensors and actuators to utilize the harvested energy for computing and communication. As the harvested energy from an energy source is limited and it takes time for a device to accumulate enough energy for data processing and communication, there is a need to investigate the energy budget and determine the critical parameters that affect the energy consumption for wireless communication. An energy consumption analysis was performed by adapting a Python model, and simulations were carried out to help understand the impact of key parameters on energy consumption while considering a suitable range for radio frequency (RF) energy harvesting “zero” energy devices. The thesis project aims to propose the design considerations of a new low-power communication protocol for “zero” energy devices. The results showed that adaptive data rate (ADR) has a major contribution to energy saving. With suitable transmitting parameters set, the energy waste of retransmissions and collisions could be reduced. It is also possible to introduce a scheduling algorithm to the communication process for improved collision avoidance. The proposed design considerations can be applied in future work to improve the shortrange communication protocol for zero-energy devices.
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Applying Deep Learning To Improve Optimization- Based Approaches For Robust Sensor FusionWikström, Pernilla January 2021 (has links)
Recent studies show that deep learning can be employed to learn from sensor data to improve accuracy and robustness of sensor fusion algorithms. In the same vein, in this thesis we use a state-of-the-art temporal convolution network to predict zero velocity updates (ZUPT) from raw inertial measurement unit (IMU) signals, and use the network output to improve the performance of an optimization-based pose estimator. Experiments were conducted on publicly available datasets, and results show that (i) the network can distinguish a car in motion vs. a car standing still by observing an IMU signal, and (ii) that ZUPT detection enhances the observability of states in the optimization-based pose estimation, thus reducing local drift. / Nyligen gjorda studier visar att djupinlärning kan användas för att lära av sensordata för att förbättra noggrannhet och robusthet hos sensorfusionsalgoritmer. På samma sätt använder vi i denna avhandling en tidsberoende faltnings neuronnätsmodell (TCN) för att detektera om ett fordon står stilla även kallat zero velocity updates (ZUPT) från IMU rå- data och använder neuronnätsprediktionen för att förbättra prestandan hos en optimeringsbaserad positionsuppskattning. Experiment utfördes på allmänt publicerade datamängder, och resultaten visar att (i) neuronnätsmodellen kan läras till att urskilja en bil i rörelse kontra en bil som står stilla genom att observera en IMU- signal, och (ii) att ZUPT- detektering förbättrar observerbarheten för tillstånd i den optimeringsbaserade positioneringsuppskattningen, vilket minskar lokal drift.
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[pt] A VOLATILIDADE IMPLÍCITA COMO PROGNÓSTICO DE RETORNO DAS AÇÕES: UMA EXPERIÊNCIA EMPÍRICA BRASILEIRA / [en] IMPLIED VOLATILITY AS A PREDICTOR OF STOCK RETURNS: A BRAZILIAN EMPIRICAL EXPERIENCESIDNEI DE OLIVEIRA CARDOSO 04 August 2022 (has links)
[pt] Esta pesquisa investiga primeiramente, por meio de regressões, a
relação entre as volatilidades implícitas das opções e os retornos futuros de
20, 40 e 60 dias das ações subjacentes no mercado acionário brasileiro. Essas
regressões são então submetidas a testes de heterocedasticidade para garantir
que não são regressões espúrias. Por fim, submetemos os resultados a um teste
de robustez que confirma as regressões válidas e verifica a presença de
autocorrelação nas séries de retornos futuros. O período analisado é de janeiro
de 2011 a dezembro de 2021 em um total de onze anos completos. Apesar de
apresentarem coeficientes de regressão significativos, nem todas essas
regressões passam pelos testes, e sempre deve-se ter cautela ao usar uma
volatilidade implícita de opção como sendo capaz de prever retornos das
ações subjacentes no mercado brasileiro. / [en] This research first investigates, through regressions, the relationship between
the implied volatilities of options and the future returns of 20, 40 and 60 days
of the underlying stocks within the Brazilian stock market. These regressions
are then subjected to heteroscedasticity tests to ensure that they are not
spurious regressions. Finally, we submit the results to robustness tests to
confirm the valid regressions and verify the presence of autocorrelation in the
series of future returns. The period under analysis is from January 2011 to
December 2021, totalling 11 years. Despite having significant regression
coefficients, not all of these regressions pass the tests, and one should always
exercise caution when using an option implied volatility as a predictor of
underlying equity returns in the Brazilian market.
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Internet of things connected notification device for people who are hard of hearingHang Shek, Wai, Geiger Ferotin, Thomas January 2022 (has links)
This degree project investigates the possibility to develop and re-design an IoT solution called NOT!FY, offered by the company Omnitor. NOT!FY is used by users who are hard of hearing or deaf as a complement to an accessibility communication application. It functions by registering incoming calls and activating a relay connected to, for example, a light source, notifying the user. The current problems that Omnitor experiences with NOT!FY is its price, production difficulties, size and design. The project will take on these problems by investigating the market of programmable devices and, through comparative analysis, choosing a platform to transfer and improve upon the current NOT!FY functionalities. The devices were decided together with Omnitor and a grant calculation was drafted to evaluate which units yielded the best profit. With the help of the grant calculation, Raspberry Pi Zero W and ESP8266 were the chosen devices. A basic evaluation was performed to verify that the implemented functions of ESP8266 and Raspberry Pi Zero W functioned as intended. An in-depth evaluation and functional verification were performed on the finalized prototype. It confirmed the prototype’s functionality and the possibility to replace the current product in use by Omnitor. / Detta projekt undersöker möjligheten att utveckla och designa om en IoT-lösning kallad NOT!FY, som erbjuds av företaget Omnitor AB. NOT!FY används av döva eller hörselskadade användare som ett komplement till en tillgänglighetsanpassad kommunikationsapplikation. Den fungerar genom att registrera inkommande samtal och aktivera ett relä som är anslutet till exempel en ljuskälla för att meddela användaren. De nuvarande problemen som Omnitor upplever med NOT!FY är dess pris, produktionssvårigheter, storlek och design. Projektet kommer att ta sig an dessa problem genom att undersöka marknaden för programmerbara enheter och genom en jämförande analys välja en plattform att överföra och förbättra funktionerna från den nuvarande produkten. Enheterna bestämdes tillsammans med Omnitor och en bidragskalkyl är framtagen för att utvärdera vilka enheter som gav bäst vinst. Med hjälp av bidragskalkylen var Raspberry Pi Zero W och ESP8266 de valda enheterna. En grundläggande utvärdering utfördes för att verifiera att de implementerade funktionerna i ESP8266 och Raspberry Pi Zero W fungerade som avsett. En mer ingående utvärdering och funktionell verifiering utfördes på den färdiga prototypen. Detta bekräftade prototypens funktionalitet och möjligheten att ersätta den nuvarande produkten som används av Omnitor.
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Implementering av Zero Trust i ett händelsestyrt meddelandesystem / Implementation of Zero Trust in an Event-Driven Messaging SystemWilson, Paul-Stefan Luay, Bahadi, Georges January 2024 (has links)
Denna rapport adresserar den centrala problemställningen kring säkerheten i händelsestyrda meddelandesystem genom att undersöka och implementera Zero Trust-arkitektur. Problemet är av stor relevans på grund av den ökande användningen av sådana system och det växande behovet av robusta säkerhetslösningar för att hantera utmaningar relaterade till asynkron kommunikation och datahantering. Zero Trust-modellen erbjuder en innovativ strategi för att förstärka säkerheten genom att eliminera implicit tillit och istället kontinuerligt verifiera användare och enheter, vilket gör det särskilt lämpligt för dynamiska och distribuerade system. Genom att utforska och analysera egenskaperna hos händelsestyrda meddelandesystem och identifiera de utmaningar som de presenterar för säkerhetsarkitekturen, undersöker rapporten en mängd olika metoder för att genomföra Zero Trust-principen. Genom en noggrann integrering av dessa metoder framhäver rapporten en effektiv och skalbar lösning för att säkra och skydda känsliga resurser och data i händelsestyrda meddelandesystem. Den presenterade lösningen belyser värdet av Zero Trust som en tillförlitlig modell för att hantera säkerhetsrisker och säkerställa en hållbar och robust arkitektur för asynkron kommunikation i moderna IT-system. / This report addresses the central issue of security in event-driven messaging systems by examining and implementing Zero Trust architecture. The problem is highly relevant due to the increasing use of such systems and the growing need for robust security solutions to manage challenges related to asynchronous communication and data handling. The Zero Trust model offers an innovative approach to enhancing security by eliminating implicit trust and instead continuously verifying users and devices, making it particularly suitable for dynamic and distributed systems. By exploring and analyzing the characteristics of event-driven messaging systems and identifying the challenges they present for security architecture, the report investigates various methods for implementing the Zero Trust principle. Through careful integration of these methods, the report highlights an effective and scalable solution for securing and protecting sensitive resources and data in event-driven messaging systems. The presented solution underscores the value of Zero Trust as a reliable model for addressing security risks and ensuring a sustainable and robust architecture for asynchronous communication in modern IT systems.
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Re-Con Zero ballast som ersättning för jungfruligt bergmaterial i betongproduktion : En studie av dess egenskaper och effekter / Re-Con Zero aggregate as a substitute for virgin aggregate material in concrete production : A study of its properties and effects.Alfara, Osama, Alfara, Ahmad January 2024 (has links)
Denna studie utforskar användningen av Re-Con Zero ballast (RCZ-ballast), ett material framställt från återvunnen betong och en tvåkomponents pulverprodukt, som ett alternativ till traditionellt jungfruligt ballastmaterial i betongproduktion. Studiens huvudsakliga syfte är att bidra till en mer hållbar och cirkulär betongindustri, där restbetong inte blir ett avfallsproblem utan en värdefull resurs. Studien vill fylla en kunskapslucka om hur RCZ-ballast påverkar betongens färska samt hårdnade egenskaper. Studien undersöker om RCZ-ballast kan matcha prestandan hos traditionellt ballastmaterial med avseende på viktiga betongegenskaper som densitet, vattenabsorption, samt mekaniska egenskaper som sättmått, lufthalt och tryckhållfasthet. Experimentella metoder inkluderade tester för att jämföra mellan betongblandningar med traditionellt ballast och den som innehåller en del RCZ-ballast. Dessa tester omfattade densitet och vattenabsorption på RCZ-ballast, dessutom mätningar av sättmått och lufthalt vid olika tider (0, 30 och 60 minuter) samt tryckhållfasthet vid olika härdningstider (1, 7 och 28 dagar) för samtliga blandningar. Resultaten från dessa tester visade att betong framställd med RCZ-ballast generellt hade högre vattenabsorption och lägre densitet jämfört med traditionella blandningar. Trots dessa material betingade skillnader uppnådde betongen med RCZ-ballast likartade tryckhållfasthetsvärden inom ramen för ett normalfördelat material vid alla testade tidpunkter. Detta visar att RCZ-ballast anses vara lämplig med avseende på tryckhållfasthet. Slutsatserna från studien understryker att RCZ-ballast, framställt från restbetong, är ett fullt fungerande alternativ till jungfruligt bergmaterial i betong, med god tryckhållfasthet. Det finns dock tydliga skillnader i sättmått, där betongens beteende varierar beroende på om den blandas med nyproducerad eller mättad RCZ-ballast. Studien avslöjar även att både nyproducerad och mättad RCZ-ballast påverkar betongens lufthalt på olika sätt jämfört med betong som är tillverkad med jungfruligt ballastmaterial. / This study explores the use of Re-Con Zero aggregates (RCZ-aggregates), a material made from recycled concrete and a two-component powder product, as an alternative to traditional virgin aggregates material in concrete production. The primary purpose of the study is to contribute to a more sustainable and circular concrete industry, where surplus or excess concrete does not become a waste problem but a valuable resource. The study aims to fill a knowledge gap regarding how RCZ-aggregates impacts the fresh and hardened properties of concrete. The study investigates whether RCZ-aggregates can match the performance of traditional aggregates materials with respect to key concrete properties such as density, water absorption, and other mechanical properties like slump, air content, and compressive strength. Experimental methods included tests to compare between concrete mixes with traditional aggregates and those containing RCZ-aggregates. These tests measured the density and water absorption of RCZ-aggregates, as well as slump and air content at different times (0, 30, and 60 minutes) and compressive strength at various curing times (1, 7, and 28 days) for all mixes. The results from these tests showed that concrete made with RCZ-aggregates generally had higher water absorption and lower density compared to traditional mixes. Despite these material-induced differences, the concrete with RCZ-aggregates achieved compressive strength values that were similarly within the range of a normally distributed material at all tested times. This demonstrates that RCZ-aggregates is considered suitable in terms of compressive strength. The conclusions from the study underscore that RCZ-aggregates , made from residual concrete, is a fully functioning alternative to virgin aggregates material in concrete, with good compressive strength. However, there are clear differences in slump, where the behavior of the concrete varies depending on whether it is mixed with newly produced or saturated RCZ-aggregates. The study also reveals that both newly produced and saturated RCZ-aggregates affect the air content of concrete differently compared to concrete made with virgin aggregates material.
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