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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.
51

Podpora kvalitativních požadavků služeb v rádiových přístupových sítích vysokorychlostních variant mobilních sítí / Support of service quality demands in radio access networks of high speed variants of mobile networks

Kuruc, Jiří January 2009 (has links)
The work deals with the developmental stages (Releases) of the third generation UMTS net-works. It explains a partial improvement from Release 99 to Release 5 and Release 6 to im-prove the quality parameters of a mobile data transmission. In the practical part, there are measured qualitative parameters of the third generation networks that are available in the Czech Republic: UMTS, HSDPA, CDMA 1xEV-DO Rev.0 and Rev.A and UMTS-TDD. The measurements give reasonably achievable data rates in both directions (downlink & uplunk), a response time, quality of VoIP calls, a dispersion, a data-loss and an ability to transmit video with different data flows. The other aspects especially an availability of coverage and end-user terminals have been assessed wihin the each network. The work is supplemeted with a laboratory, which is focused on a practical comparison of the basic parameters of data transmissions of 2G and 3G networks.
52

Selecting unit testing framework for embedded microcontroller development

Toth, Jonatan, Karlsson, Fredrik January 2021 (has links)
In this study, the absence of enough usage of the agile methodology Test-driven development among embedded developers was highlighted, and a solution for getting more developers to start using that methodology was researched into. The research revolved around making the practice of unit testing, which is a large part of the test-driven development methodology, more available to developers by lowering the knowledge threshold of which unit testing framework to choose and how they work. The area of embedded development was narrowed down to the usage of microcontrollers and the development of software for those in the programming language C. This study managed to firstly gather the general opinion of developers of which the most sought after criteria was that a unit testing framework for embedded development should support. With the help of those criteria, an extensive comparison could be done between some of the most popular and recommended unit testing frameworks for embedded microcontroller development. The observations that was made during the experiment were then used to take away some lessons learned that could form recommendations containing information about which unit testing framework that should be used depending on which preferences a developer could have.
53

Epitaxy and Characterization of Metamorphic Semiconductorsfor III-V/Si Multijunction Photovoltaics

Boyer, Jacob Tyler January 2020 (has links)
No description available.
54

Relative Bio-Equivalence of Salbutamol MDIs Without and With the Attached Spacers. Development and validation of novel HPLC methods for the determination of salbutamol (and terbutaline) in urine excreted post-inhalation for bioequivalence and pharmacokinetic studies of Salbutamol MDIs

Mazhar, Syed H.R. January 2018 (has links)
This research explored in-vitro and in-vivo performance of three salbutamol metered dose inhalers (MDIs): Ventolin Evohaler (Evo), Airomir (Airo) and Salamol. In the in-vitro studies, critical quality attributes of the MDI using an Andersen cascade impactor (ACI) were examined and included measurement of fine particle dose (FPD) and total delivered dose (TDD). Bioequivalence studies were conducted in humans using the urinary pharmacokinetic method. Post-inhalation urinary excretion of salbutamol in the first 0.5 hour (lung deposition, USAL0.5) and over 24 hours (total systemic bioavailability, USAL24) were compared to determine the bioequivalence of the MDIs. The spacers recommended for use with these inhalers were also studied, and charcoal block studies were performed to assess the extent of USAL0.5. The three MDIs had FPD (μg) of 78, 91 and 89, respectively; the latter pair was equivalent. Their USAL0.5 (6, 7 & 7 μg) was however not bioequivalent. These MDIs delivered equivalent dose (177, 174 & 180 μg) which reflected on their USAL24 (101, 84 & 97 μg). Nevertheless, USAL24 was inequivalent between Evo and Airo. The FPD of Evo with Volumatic (VOL), AeroChamber Plus (AERO) and Able spacer was 78, 68 and 74 μg, respectively. The AERO treatment method was not equivalent to the MDI while VOL and Able were equivalent between them. Spacer USAL0.5 (16, 15 & 14 μg) was not bioequivalent to the MDI but to each other. The spacer in-vitro TDD (95, 85 & 92 μg) was inequivalent to the MDI treatment method. In contrast, their USAL24 was bioequivalent (97, 85 & 90 μg). The FPD of Airomir with AERO (95 μg) was in-vitro equivalent while USAL0.5 (15 μg) of this treatment method was bio-inequivalent to the MDI alone. On the contrary, the TDD (110 μg) and USAL24 (84 μg) of AERO were respectively in-vitro inequivalent and bioequivalent to the MDI alone. The FPD (μg) of Salamol MDI alone and with VOL (84) and AERO (86) as well as between the spacers was equivalent. However, the USAL0.5 of the MDI was not bioequivalent to spacers (20 and 18 μg) despite being equivalent between the spacers. In contrast, the respective TDD (103 and 95 μg) of spacer treatment methods were in-vitro inequivalent to the MDI alone albeit having bioequivalent USAL24 (86 and 87 μg). The variations in the in-vitro performance of the three MDIs are most likely due to differences in their formulations and designs. As the performance metrics of the MDI influence lung deposition, substituting one MDI with another can have clinical implications. Although the spacers reduced in-vitro TDD of the MDI to about half, their use increased lung deposition by over two folds, the magnitude of which varied with the MDI and spacer type. Despite significant decrease in dose delivery, the total systemic bioavailability with the spacers was similar to that with the MDI alone. This systemic bioequivalence is more likely due to greater USAL0.5 with the spacers. The results of the charcoal block studies reinforced this outcome. The present study is unique as it used a clinically relevant salbutamol MDI dose (two puffs), assessed results for equivalence and analysed ACI deposition data further as stage groups. The deposition on adjacent ACI stages were grouped together as coarse, fine and extra-fine particle masses to identify their more likely deposition sites in the human respiratory tract. Moreover, this thesis describes highly sensitive and novel HPLC and SPE methods, developed and validated to quantify salbutamol in urinary and aqueous matrices. As the clinical effects of MDIs are related to their lung deposition, the current work emphasizes the importance of spacer use. Nevertheless, differences in dose delivery between spacers may have clinical consequences. Hence, only the specific spacer recommended for use with the MDI should be used. / World Federation, Stanmore, London and Sadaat Welfare Foundation, Bradford, West Yorkshire
55

Spatial Modelling of Monthly Climate Across Mountainous Terrain in Southern Yukon and Northern British Columbia

Ackerman, Hannah 11 November 2022 (has links)
Two measures of air temperature trends across southern Yukon and northern British Columbia were modelled based on measurements from 83 monitoring sites across seven areas, operating for up to 14 years. Both mean monthly air temperature (MMAT) and freezing and thawing degree days (FDD and TDD, respectively) were modelled across this area (59 °N to 64.5 °N) at elevations ranging from 330-1480 m asl. Lapse rates in this region show inversions in the winter months (November - March) varying in inversion strength and length in relation to degree of continentality. The spatial and elevation range of these sites allowed for regional lapse rate modelling at the monthly scale for MMAT and at the annual scale for FDD and TDD. Lapse rates below treeline were found to be correlated (p < 0.1) with degree of continentality in the colder months (November - April) and August. In these months, lapse rates were modelled using kriging trend surfaces. In months where degree of continentality was not found to have a significant impact on lapse rates (p > 0.1) (May - October, excluding August), an average lapse rate calculated from the seven study regions was used across the study region. A combination of lapse rate trend surfaces, elevation, and temperatures at sea level were used to model MMAT and F/TDD below treeline. A treeline trend surface was created using a 4th order polynomial, allowing for temperatures at treeline to be determined. MMAT and F/TDD above treeline were calculated using a constant lapse rate of -6 °C/km, elevation, and temperature at treeline. The above and below treeline models were combined to create continuous models of MMAT and F/TDD. Modelled MMAT showed a high degree of homogeneity across the study region in warmer months. Inversions in lapse rates are evident in the colder months, especially December through February, when colder temperatures are easily identified in valley bottoms, increasing to treeline, and decreasing above treeline. Modelled MMAT values were validated using 20 sites across the study region, using both Environment and Climate Change Canada and University of Ottawa sites. The RMSE between modelled and observed MMAT was highest in January (4.4 °C) and lowest in June (0.7 °C). Sites below treeline showed a stronger relationship between modelled and observed values than sites above treeline. Edge effects of the model were evident in the northeast of the study region as well as in the ice fields in the southwest along the Alaska border. The new MMAT maps can be used to help understand species range change, underlying permafrost conditions, and climate patterns over time. FDD values were found to be highly influenced by both degree of continentality as well as latitude, whereas TDD values were mainly dependent on elevation, with degree of continentality and latitude being lesser influences. FDD and TDD were validated using the same 20 sites across the study region, with FDD showing a larger RMSE (368 degree days) between modelled and observed values than TDD (150 degree days). TDD modelling performed better on average, with a lower average absolute difference (254 degree days) between modelled and observed values at the validation sites than FDD modelling (947 degree days). The models of FDD and TDD represent a component of temperature at top of permafrost (TTOP) modelling for future studies. Two mean annual air temperature (MAAT) maps were created, one calculated from the MMAT models, and the other from the F/TDD models. Most of the study region showed negative MAAT, mainly between -6 °C and 0 °C for both methods. The average MAAT calculated from FDD and TDD values was -2.4 ºC, whereas the average MAAT calculated from MMAT values was -2.8 ºC. Models of MAAT were found to be slightly warmer than in previous studies, potentially indicating warming temperature trends.
56

Stratégies de coopération dans les réseaux radio cognitif / Cooperation strategies in radio cognitive networks

Kouassi, Boris Rodrigue 25 October 2013 (has links)
Les réseaux radio actuelles utilisent le spectre inefficacement, car une bande de fréquence est allouée de façon permanente à une technologie spécifique. Vu que le spectre est une ressource limitée, cette attribution statique ne pourra bientôt plus combler les besoins des systèmes de transmission qui ne cessent de croître. On peut toutefois optimiser l'utilisation du spectre en permettant des transmissions secondaires (SU) dans les espaces libres du primaire (PU). Cette vision constitue l'objectif principal de la radio cognitive. Nous proposons d'évaluer les stratégies de transmission pour la coexistence des systèmes primaires (PU) et SU dans les mêmes réseaux. Plus concrètement, nous nous focalisons sur un scénario spatial interweave en émettant les signaux SU dans les espaces vides du PU à l'aide d'un précodeur linéaire. Néanmoins, ce précodage nécessite une connaissance a priori des canaux interférents. L'échange d'informations entre le PU et le SU étant proscrit, nous exploitons l'hypothèse de la réciprocité du canal. Cette hypothèse compense l'absence de coopération, mais elle n'est pas si évidente à exploiter en pratique à cause des perturbations des circuits radio fréquence. Nous suggérons de compenser ces perturbations par des méthodes de calibration relative. Nous proposons ensuite une implémentation temps-réel des solutions sur une plateforme LTE. Pour finir, nous généralisons l'approche RC à un système de transmission multi-utilisateurs, à travers une combinaison des techniques RC et massive MIMO, cette approche constitue s’établit comme une solution à la progression exponentielle du trafic. / The accelerated evolution of wireless transmission in recent years has dramatically increased the spectrum overcrowding. Indeed, the spectrum is inefficiently used in the conventional networks, since a frequency band is statically allocated to a specific technology called primary (PU). Whereas the radio spectrum is limited, this static frequency allocation will no longer be able to meet the increasing needs of bandwidth. However, the spectrum can be optimally used in enabling secondary (SU) transmissions, provided the latters do not harm the PU. This opportunistic vision of wireless transmissions is the main aim of Cognitive Radio (CR). CR enables smart use of wireless resources and is a key ingredient to perform high spectral efficiency. We focus on a spatial interweave (SIW) CR scenario which exploits the spatial white spaces to enable SU transmissions. The latter forms spatial beams using precoders, so that there is no interference towards the primary. Nevertheless, this precoding requires acquisition of the crosslink channel. However, due to the lack of cooperation between PU and SU, we acquire the channel thanks to channel reciprocity. Furthermore, the practical use of the reciprocity is not as straightforward as in theory, because it is is jeopardized by the nonreciprocal radio frequency front-ends. These perturbations are compensated in our study by relative calibration algorithms. Subsequently, we propose an implementation of our solutions in a real-time LTE platform. Eventually, we extend the CR model to a MU system in suggesting a combination of SIW and massive MIMO techniques. This scheme is an interesting candidate to overcome the exponential traffic growth.
57

Přenosová technologie G.mgfast / G.mgfast transmission technology

Rada, Dominik January 2021 (has links)
The master thesis deals with G.fast and G.mgfast transmission technologies, including their parameters. The work deals with the principle of vector DMT modulation and the possibility of time duplex TDD and full-duplex FDX in two-way communication used in these technologies. The following is a description of the line using the KHM model, which is suitable for simulations in the transmission band using G.fast and G.mgfast technologies. Subsequently, the disturbing effects of crosstalk at the near end of NEXT and the far end of FEXT and their elimination with these technologies are discussing. Part of the work explains supporting calculations to determine the SNR and bit allocation to calculate the baud rate. The work describes the methods of compensation of crosstalk FEXT and NEXT, which affect the resulting baud rate. The work also includes an application for simulation of transmission speed as a function of distance for G.fast and G.mgfast technologies, allowing changing input parameters and adjusting the transmission bandwidth based on G.9700 and G.9701 standards. Also, in work, an application is created to display the compensation of the influence of the transmitted signal crosstalk FEXT and NEXT, which allow the import of measured crosstalk between individual participants. The issue of influencing crosstalk for accurate measurements in the laboratory is also discussing. An application in the MATLAB environment is creating to display the measured characteristics.
58

Mécanisme d’accélération d’une flamme de prémélange hydrogène/air et effets sur les structures / Flame propagation mechanisms of premixed hydrogen/air mixtures and effects of combustion generated loads on structures

Scarpa, Roberta 19 December 2017 (has links)
Le risque d’explosion des mélanges H2/air revêt toujours une importance cruciale pour la gestion des accidents graves dans les centrales nucléaires. Des critères expérimentaux ont été proposés dans les années 2000 par Dorofeev et al. afin de déterminer les conditions nécessaires à l’accélération de flamme et à la TDD. Ce travail de thèse a l’objectif de mieux comprendre les mécanismes d’accélération des flammes de prémélange H2/air et de fournir une solide base de données expérimentales pour la validation des codes utilisés pour les études de sûreté. Les expériences ont été menées dans un tube muni d’obstacles (taux de blocage entre 0.3 et 0.6) avec un diamètre interne de 12 cm et une longueur d’environ 5 m. Les effets de la pression initiale et de la dilution en azote sur des mélanges pauvres en H2 ont été étudiés. Les résultats montrent que la pression favorise l’accélération seulement pour les mélanges les plus réactifs et que la surpression induite par la combustion est directement proportionnelle à la pression initiale. Les interactions flamme-choc ainsi que les instabilités thermo-diffusives jouent un rôle important sur la propagation de flamme. Une nouvelle technique a été développée dans le but d’obtenir une représentation plus fine du profil de vitesse de flamme. Des mesures d’absorption IR résolues dans le temps ont été effectuées en dopant le mélange avec un alcane. Le profil de vitesse a été obtenu en mesurant la variation d’extension du gaz frais pendant l’avancement de la flamme. Enfin, des analyses préliminaires ont été menées pour la conception d’un nouveau dispositif expérimental pour l’étude des effets de la combustion sur des structures en acier inox. / Flame acceleration and explosion of hydrogen/air mixtures remain key issues for severe accident management in nuclear power plants. Empirical criteria were developed in the early 2000s by Dorofeev and colleagues providing effective tools to discern possible FA or DDT scenarios. The objectives of the present work are to better understand the mechanisms of acceleration for premixed H2/air flames and to provide a solid base of experimental data for the validation of the codes used for safety analyses. The experiments were performed in an obstacles-laden tube (blockage ratio between 0.3 and 0.6) with 120 mm internal diameter and about 5 m length. The effects of the initial pressure and the nitrogen dilution on lean H2 mixtures have been studied. The results show that pressure promote flame acceleration only for highly reactive mixtures. Moreover, the overpressure induced by the combustion is directly proportional to the initial pressure. Besides, flame-shock interactions and thermo-diffusive instabilities play an important role in flame acceleration. A new technique to track the flame position along the tube has been developed in order to obtain a finer representation of the flame velocity profile. The method consists in performing time-resolved IR absorption measurements by doping the mixture with an alkane. The velocity profile is then derivedby measuring the variation of the extension in depth of the unburnt gas along the tube axis. Finally, analyses on the effects of combustion generated loads on stainless steel structures were performed in order to provide preliminary results for the design of a new experimental device.
59

Integração da abordagem Domain-Driven Design e de técnica Behaviour-Driven Development no desenvolvimento de aplicações web

Santos, Eloisa Cristina Silva 01 June 2015 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2016-09-30T12:23:06Z No. of bitstreams: 1 DissECSS.pdf: 2536269 bytes, checksum: a856f5027d19c2aaadf2834a69af7ff4 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-09-30T17:56:23Z (GMT) No. of bitstreams: 1 DissECSS.pdf: 2536269 bytes, checksum: a856f5027d19c2aaadf2834a69af7ff4 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-09-30T17:56:32Z (GMT) No. of bitstreams: 1 DissECSS.pdf: 2536269 bytes, checksum: a856f5027d19c2aaadf2834a69af7ff4 (MD5) / Made available in DSpace on 2016-09-30T18:05:54Z (GMT). No. of bitstreams: 1 DissECSS.pdf: 2536269 bytes, checksum: a856f5027d19c2aaadf2834a69af7ff4 (MD5) Previous issue date: 2015-06-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / The agile methods of software development have emerged as an alternative to traditional approaches, to spend less time on documentation and more time with solving problems interactively and iteratively. In this context, the development approach Domain Driven Design (DDD) is a way of developing software in which the application design process is guided by a domain model. In conjunction with the DDD development approach, the existence of tests during the implementation of an application is required to ensure quality. Objective: This work aims to study the agile development approach Domain-Driven Design (DDD) and the software test techniques Test-Driven Development (TDD) and Behaviour-Driven Development (BDD). A case study was built to exemplify the integration of each test technique with DDD. The case study was developed with the support of the Apache Isis framework, from a well-defined domain model. Methodology: Based on the literature, the concepts of the DDD development approach and of the TDD and BDD test techniques, that provided the comparison between the techniques, and later, the implementation to illustrate this research, were extracted. The Apache Isis framework was used in this work because it allows develop DDD applications quickly. During the development of the sample system of this work, the possibility of creating an automatic generator tests and scenarios for BDD was noted. Results: A case study was created using the concepts of DDD and tests, with TDD and BDD. Furthermore, a prototype of tests and scenarios generator for software projects that use DDD, through the Apache Isis framework and tests using BDD, was developed. Conclusions: The combination of test techniques mentioned with DDD aim to boosting the development of applications, since DDD is not associate with any test technique. Writing scenarios with ubiquitous language is a great advantage to integrate DDD and BDD, because it allows a clear understanding for all involved in the project. Moreover, the creation of automatic generator speeds up the testing phase, and can detect errors that might go unnoticed or only be found as the project evolved. / Os métodos ágeis de desenvolvimento de software surgiram como uma alternativa às abordagens tradicionais, com o intuito de despender menos tempo com documentação e mais com a resolução de problemas de forma interativa e iterativa. Neste contexto, a abordagem de desenvolvimento Domain-Driven Design (DDD) representa uma forma de desenvolver software em que o processo de design de uma aplicação é guiado pelo modelo de domínio. Em conjunto com a abordagem de desenvolvimento DDD, a existência de testes durante a implementação de uma aplicação é necessária para garantir a qualidade. Objetivo: Este trabalho teve como objetivo o estudo da abordagem ágil de desenvolvimento Domain-Driven Design (DDD) e as técnicas de teste de software Test-Driven Development (TDD) e Behaviour-Driven Development (BDD). Um estudo de caso foi construído para exemplificar a integração de cada técnica de teste com o DDD. O estudo de caso foi desenvolvido por meio do framework Apache Isis, a partir de um modelo de domínio bem definido. Metodologia: Com base na literatura foram extraídos os conceitos da abordagem de desenvolvimento DDD e das técnicas de testes TDD e BDD que proporcionaram a comparação entre as técnicas e posterior implementação para exemplificar a pesquisa. O framework Apache Isis foi utilizado neste trabalho porque permite desenvolver aplicações com DDD de forma rápida. No decorrer do desenvolvimento do sistema exemplo deste trabalho, notou-se a possibilidade da criação de um gerador automático de testes e cenários para BDD. Resultados: Foi criado um estudo de caso empregando os conceitos de DDD e testes com o TDD e com o BDD. Além disso, foi desenvolvido um protótipo de gerador de testes e cenários para projetos de software que empregam DDD, por meio do framework Apache Isis e testes utilizando BDD. Conclusões: A junção das técnicas de testes citadas com o DDD visa potencializar o desenvolvimento de aplicações, uma vez que o DDD não aborda nenhuma técnica de teste. A escrita de cenários em linguagem ubíqua é um grande diferencial ao integrar DDD e BDD, pois permite um claro entendimento a todos os envolvidos do projeto. Ademais, a criação do gerador automático agiliza a fase de testes, sendo possível detectar erros que poderiam não ser notados ou apenas serem encontrados com a evolução do projeto.
60

Queued and Pooled Semantics for State Machines in the Umple Model-Oriented Programming Language

Alghamdi, Aliaa January 2015 (has links)
This thesis describes extensions to state machines in the Umple model-oriented programming language to offer queued state machines (QSM), pooled state machines (PSM) and handing of the arrival of unexpected events. These features allow for modeling the behavior of a system or protocol in a more accurate way in Umple because they enable detecting and fixing common design errors such as unspecified receptions. In addition, they simplify the communication between communicating state machines by allowing for asynchronous calls of events and passing of messages between state machines. Also, a pooled state machine (PSM) has been developed to provide a different policy of handling events that avoid unspecified receptions. This mechanism has similar semantics as a queued state machine, but it differs in the way of detecting unspecified receptions because it helps handling these errors. Another mechanism has been designed to use the keyword ‘unspecified’ in whatever state of a state machine the user wants to detect these errors. In this thesis, the test-driven development (TDD) process has been followed to first modify the Umple syntax to add ‘queued,’ ‘pooled,’ and ‘unspecified’ keywords to Umple state machine’s grammar; and second, to make a change to the Umple semantics in order to implement these extensions in Umple. Then, additional modifications have been made to allow for Java code generation from those types of state machines. Finally, more test cases have been written to ensure that these models are syntactically and semantically correct. In order to show the usefulness and usability of these new features, an example is shown as a case study that is modeled using the queued state machine (QSM) besides other small tests cases.

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