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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.
1

Elaboração de um material didático aplicado ao ensino de física para utilização do experimento virtual da dupla fenda / Preparation of a didactic material to the physical education for use of virtual experiment of double-slit

Ferreira, Danilo Cardoso [UNESP] 15 December 2015 (has links)
Submitted by DANILO CARDOSO FERREIRA null (danilofunesp@hotmail.com) on 2016-01-15T16:37:27Z No. of bitstreams: 1 DaniloCardosoFerreiraDissertação.pdf: 18302953 bytes, checksum: 3c2360f40af22ce571ff0f502e07fce0 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-01-18T11:54:59Z (GMT) No. of bitstreams: 1 ferreira_dc_me_prud_par.pdf: 828636 bytes, checksum: 12854c3c461e55dc7897bb0c5127d4a8 (MD5) / Made available in DSpace on 2016-01-18T11:54:59Z (GMT). No. of bitstreams: 1 ferreira_dc_me_prud_par.pdf: 828636 bytes, checksum: 12854c3c461e55dc7897bb0c5127d4a8 (MD5) Previous issue date: 2015-12-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A mecânica quântica é uma das áreas da Física que surgiu em meados de 1900 e permanece em desenvolvimento até os dias atuais. Diversos aparatos tecnológicos são consequência deste importante ramo da Física que também contribui com a Medicina, Matemática, Filosofia, Literatura e Biologia. Logo, é imprescindível que o contato com esta ciência ocorra no contexto do ensino médio. Para inserir o estudante no mundo da mecânica quântica, isto é, na física do infinitamente pequeno, o aluno deve abandonar o pensamento clássico e pensar em termos do comportamento quântico e do indeterminismo no processo de medida, isto é, desenvolver a capacidade de abstração. Sendo este, o objetivo deste trabalho. Para tanto, foi escolhido o experimento da dupla fenda que permite trabalhar com a dualidade onda-partícula do elétron e do fóton. Por meio deste experimento, o aluno pode ser inserido paulatinamente numa trajetória rumo a descrição quântica necessária para o exame dos fenômenos subatômicos. A análise experimental é cuidadosamente realizada com o auxílio de laboratórios virtuais, disponibilizados gratuitamente em sítios eletrônicos, os quais representam um recurso que permite realizar procedimentos experimentais que necessitariam de grande aparato laboratorial. O experimento da dupla fenda é analisado em três etapas, relatadas a seguir: (i) a dupla fenda com partículas clássicas; (ii) a dupla fenda com ondas clássicas e; (iii) a dupla fenda com objetos quânticos como elétrons e fótons. O objetivo é demonstrar o comportamento dual do elétron. Posteriormente, para concluir de forma precisa e justificar o comportamento quântico do elétron é apresentado o princípio da indeterminação de Heisenberg e suas implicações filosóficas. Sendo assim, o objetivo central desta pesquisa é buscar integrar o comportamento quântico, que acontece na escala atômica, principalmente no contexto do ensino médio. Algumas orientações sobre como aplicar este trabalho em outros níveis de ensino aparecem no decorrer do texto e nos apêndices. Apresentando o comportamento dual, onda–partícula, do elétron, a interpretação probabilística e o princípio de incerteza. Acreditamos que o aluno será capaz de compreender um grande número de fenômenos que acontece em escalas que não são do domínio da mecânica clássica quando, em contato com estes temas. Este tema faz parte do conteúdo de física moderna contemporânea que vem sendo abordado em livros textos e vestibulares. Além disso, algumas das novas tecnologias utilizam a física quântica, desde microscópios eletrônicos, nanotecnologia, computação quântica, semicondutores, diodos (incluindo o LED), transistores, computadores, tablets, GPS, satélites, radares, aviões, lasers, scanners de código de barras, sistemas militares de defesa, CD e Blu-Ray players, criptografia, células fotoelétricas, sensores diversos, basicamente, tudo que é eletrônico. Um dos objetivos do trabalho é verificar quais os conhecimentos prévios o corpo discente possui, antes do contato com o conteúdo de física quântica, ou seja, o que faz parte do senso comum sobre este tema. Além disso, pretendemos verificar se o aluno consegue: i) distinguir, no final da aplicação desta pesquisa, que as leis da física em escalas atômicas são diferentes das leis da física clássica, ii) a importância da mecânica quântica na tecnologia e na sociedade. / Quantum mechanics is one of the areas of physics that emerged in mid-1900 and remains in development to the current day. Several technological devices are a result of this important branch of physics that also helps to Medicine, Mathematics, Philosophy, Literature and Biology. Therefore, it is essential that contact with this science occurs at the high school level, what actually occurs in a limited way, when it happens. To place the student in the world of quantum mechanics, that is, the infinitely small of physics, the student must leave the classical thought and think in terms of the quantum behavior and indeterminacy in the measurement process, namely to develop the capacity for abstraction. This is accurately the aim of this work. Thus, the double-slit experiment that lets you work with the wave-particle duality of the electron and the photon was chosen. Through this experiment, students can be gradually inserted on a path toward quantum description necessary for the examination of subatomic phenomena. The experimental analysis is carefully performed with the aid of virtual laboratories, available for free in electronic sites, which represent a resource to perform experimental procedures that would require large laboratory apparatus. The double slit experiment is analyzed in the following three steps, reported: (i) the slit paired with classical particles; (ii) the double slit and with classical waves; (iii) the double slit with quantum objects such as electrons and photons. The goal is to demonstrate the electron dual behavior. Later to complete accurately and justify the electron quantum behavior shows the principle of indeterminacy of Heisenberg and its philosophical implications. Thus, the main objective of this research is to seek to integrate quantum behavior, which takes place at the atomic scale, especially in the high school level. Some guidance on how to apply this work in other levels of education appear throughout the text and in the appendices. Introducing the dual behavior wave-particle, the electron, the probabilistic interpretation and the uncertainty principle. We believe that students will be able to understand a number of phenomena that occurs on scales that are not the classical mechanics of the domain when in contact with these topics. This topic is part of the contemporary modern physics content that is being addressed in texts and entrance exam books. In addition, some of the new technologies using quantum physics, from electronic microscopes, nanotechnology, quantum computing, semiconductors, diodes (including LED), transistors, computers, tablets, GPS, satellites, radar, aircraft, lasers, code scanners bars, military defense systems, CD and Blu-Ray players, encryption, photoelectric cells, various sensors, basically, everything is electronic. One of the goals of the work is to check what prior knowledge the student body has, before contact with quantum physics content, so the part of common sense on this issue. In addition, we intend to verify that the student is able to: i) distinguish, at the end of the application of this research, that the laws of physics at atomic scales are different from the laws of classical physics, ii) the importance of quantum mechanics in technology and society.
2

Virtual experiments as a contribution to the management of rivers impacted by microbial pollution and antibiotic resistance

Mishra, Sulagna 18 July 2024 (has links)
The contamination of rivers with potentially pathogenic bacteria poses health risks for users. This is particularly true when the bacteria are carriers of antibiotic resistance genes (ARG). Pathogenic bacteria and ARG are primarily discharged into rivers from wastewater treatment plants (WWTP). There, ARG are subject to the processes of transport, retention, and degradation. Simultaneously, they can also propagate through the growth of the carrier bacteria and by horizontal gene transfer. According to the current state of knowledge, the horizontal transfer of ARG is mediated predominantly by plasmid transfer. While the transport of bacteria in rivers has been intensively investigated, the relationship between the location of the wastewater discharges and their impact on microbial (and ARG) loading in the receiving waters downstream remains largely unexplored. Process-based mathematical models have been designed in the past to specifically describe the plasmid-mediated transfer of ARG. However, these models are used with numerous pragmatic simplifications whose effects on the computational outcomes have not been systematically examined. The present work uses virtual experiments (VE) to answer crucial questions regarding the spread of ARG in rivers. On the one hand, VE are used to compare alternative configurations of WWTP (in terms of size and location) within a catchment with respect to the resulting microbial contamination in the river network. On the other hand, VE are used to quantify the biases that arise in the estimation of plasmid transfer rates from laboratory experiments when the mathematical models used for this purpose have structural deficiencies. The rates of plasmid transfer determined from laboratory experiments provide an initial basis for assessing the potential importance of the horizontal transfer of ARG occurring in the water column along rivers. The knowledge gained makes an important contribution to describing the spread of ARG in rivers in the future through mathematical models and to identifying possible mitigation measures.
3

State-of-health estimation by virtual experiments using recurrent decoder-encoder based lithium-ion digital battery twins trained on unstructured battery data

Schmitt, Jakob, Horstkötter, Ivo, Bäker, Bernard 15 March 2024 (has links)
Due to the large share of production costs, the lifespan of an electric vehicle’s (EV) lithium-ion traction battery should be as long as possible. The optimisation of the EV’s operating strategy with regard to battery life requires a regular evaluation of the battery’s state-of-health (SOH). Yet the SOH, the remaining battery capacity, cannot be measured directly through sensors but requires the elaborate conduction of special characterisation tests. Considering the limited number of test facilities as well as the rapidly growing number of EVs, time-efficient and scalable SOH estimation methods are urgently needed and are the object of investigation in this work. The developed virtual SOH experiment originates from the incremental capacity measurement and solely relies on the commonly logged battery management system (BMS) signals to train the digital battery twins. The first examined dataset with identical load profiles for new and aged battery state serves as proof of concept. The successful SOH estimation based on the second dataset that consists of varying load profiles with increased complexity constitutes a step towards the application on real driving cycles. Assuming that the load cycles contain pauses and start from the fully charged battery state, the SOH estimation succeeds either through a steady shift of the load sequences (variant one) with an average deviation of 0.36% or by random alignment of the dataset’s subsequences (variant two) with 1.04%. In contrast to continuous capacity tests, the presented framework does not impose restrictions to small currents. It is entirely independent of the prevailing and unknown ageing condition due to the application of battery models based on the novel encoder–decoder architecture and thus provides the cornerstone for a scalable and robust estimation of battery capacity on a pure data basis.

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