Spelling suggestions: "subject:"proof off concept"" "subject:"proof oof concept""
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A RESAMPLING BASED APPROACH IN EVALUATION OF DOSE-RESPONSE MODELSFu, Min January 2014 (has links)
In this dissertation, we propose a computational approach using a resampling based permutation test as an alternative to MCP-Mod (a hybrid framework integrating the multiple comparison procedure and the modeling technique) and gMCP-Mod (generalized MCP-Mod) [11], [29] in the step of identifying significant dose-response signals via model selection. We name our proposed approach RMCP-Mod or gRMCP-Mod correspondingly. The RMCP-Mod/gRMCP-Mod transforms the drug dose comparisons into a dose-response model selection issue via multiple hypotheses testing, an area where not much extended researches have been done, and solve it using resampling based multiple testing procedures [38]. The proposed approach avoids the inclusion of the prior dose-response knowledge known as "guesstimates" used in the model selection step of the MCP-Mod/gMCP-Mod framework, and therefore reduces the uncertainty in the significant model identification. When a new drug is being developed to treat patients with a specified disease, one of the key steps is to discover an optimal drug dose or doses that would produce the desired clinical effect with an acceptable level of toxicity. In order to nd such a dose or doses (different doses may be able to produce the same or better clinical effect with similar acceptable toxicity), the underlying dose-response signals need to be identified and thoroughly examined through statistical analyses. A dose-response signal refers to the fact that a drug has different clinical effects at many quantitative dose levels. Statistically speaking, the dose-response signal is a numeric relationship curve (shape) between drug doses and the clinical effects in quantitative measures. It's often been a challenge to nd correct and accurate efficacy and/or safety dose-response signals that would best describe the dose-effect relationship in the drug development process via conventional statistical methods because the conventional methods tend to either focus on a fixed, small number of quantitative dosages or evaluate multiple pre-denied dose-response models without Type I error control. In searching for more efficient methods, a framework of combining both multiple comparisons procedure (MCP) and model-based (Mod) techniques acronymed MCP-Mod was developed by F. Bretz, J. C. Pinheiro, and M. Branson [11] to handle normally distributed, homoscedastic dose response observations. Subsequently, a generalized version of the MCP- Mod named gMCP-Mod which can additionally deal with binary, counts, or time-to-event dose-response data as well as repeated measurements over time was developed by J. C. Pinheiro, B. Bornkamp, E. Glimm and F. Bretz [29]. The MCP-Mod/gMCP-Mod uses the guesstimates" in the MCP step to pre-specify parameters of the candidate models; however, in situations where the prior knowledge of the dose-response information is difficult to obtain, the uncertainties could be introduced into the model selection process, impacting on the correctness of the model identification. Throughout the evaluation of its application to the hypothetical and real study examples as well as simulation comparisons to the MCP-Mod/gMCP-Mod, our proposed approach, RMCP-Mod/gRMCP-Mod seems a viable method that can be used in the practice with some further improvements and researches that are still needed in applications to broader dose-response data types. / Statistics
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Evaluating performance of a React Native feature setJohansson, Erik, Söderberg, Jesper January 2018 (has links)
React Native has quickly become one of the most popular cross-platform frameworks for developing Android and iOS applications since it was first released by Facebook in 2015. In this study a proof of concept application is developed and a set of features are evaluated with regard to performance efficiency. Results of measurements show that while React Native does perform worse than it's Android counterpart, it performs sufficiently well for building most applications with but can be more problematic for applications running heavier client-side logic.
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Proof-of-Concept för framtida värdeflöden med aggregerad simulering / Proof-of-Concept for future value streams with the usage of aggregated simulationsHolm Svensson, Tim, Suljic, Eddie January 2022 (has links)
Studien presenterar hur Södra Wood kan applicera diskret händelsestyrd simulering (DES) genom modeller på sågverk för att bland annat öka produktionsvolym, förkorta ledtider och minska lagernivåer. Med hjälp av digitala verktyg som FACTS Analyzer simulerades önskade förändringar på produktionsflödet och även andra organisationella förändringar. Utfallet av de simulerade förändringarna resulterade i flertalet positiva slutsatser som kunde presenteras och även visualiseras. Bevisligen kan simuleringar användas som grund till diverse besulttaganden och vidare även till Proof-Of-Concept trots att aggregerade modeller används. Det finns dock mycket utrymme kvar till vidareutveckling av denna typ av arbeten där värdeflödet i industrier av denna domän kan gynnas väsentligt.
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Design and synthesis of a software-based transceiver PHY controllerRanco, Annarita January 2018 (has links)
Companies developing integrated circuits are expected to enhance their products’ performance at every new release, while reducing size and power consumption. The demand for more elaborate and diverse functionality, together with a reduced time-to-market, irremediably raises costs and increases the probability of bugs. Even high-performance ASICs are not immune: the complexity of the design flow implies significant non-recurring engineering and production costs. Similar challenges affect the FPGA design flow, where the allocation of programmable logic requires considerable engineering effort. Moreover, due to the limited visibility of internal operations, isolating and back-tracing malfunctions are open challenges. Ericsson AB is exploring novel approaches to deal with this complex ecosystem.This thesis investigates the feasibility and the benefits of a flexible design approach, by developing and characterizing a Proof-of-Concept (PoC) transceiver handler for highspeed link applications. The flexibility lies in the software-based controller, exploited to handle the reset and dynamic reconfiguration of a transceiver physical layer (PHY). The objective of the software implementation is to simplify error detection and on-the-fly modification compared to a traditional HW-based controller. The firmware, running on a Nios II soft-core processor, drives the control signals while monitoring the transceiver’s status. Unexpected synchronization losses are handled by a dedicated Interrupt Service Routine.The correct HW/SW interaction has been tested through simulation, whereas the software profiling proves that the timing requirements are met (only 167µs are spent on the reset sequence). Finally, the PoC has been benchmarked against an analogous system with a traditional HW-based controller, to evaluate the drawbacks of the introduction of a soft-core processor (in terms of logic utilization and power consumption).Despite the promising engineering effort reduction, further research is required to scale up the system and move from the PoC stage towards product release. / Företag som utvecklar integrerade kretsar förväntas öka prestandan i nya produkter, och samtidigt reducera storlek samt effektförbrukning. Efterfrågan på mer komplicerad funktionalitet, tillsammans med förkortad time-to-market, orsakar oundvikligen högre kostnader och ökad sannolikhet för buggar. Även högprestererande ASICs drabbas av detta: det komplicerade designflödet resulterar i signifikanta engångskostnader för teknisk utveckling samt tillverkning. Liknande utmaningar påverkar designflödet hos FPGA:er, där allokeringen av programmerbar logik kräver påtagligt utvecklingsarbete. Eftersom insynen i interna operationer är begränsad är isolation och spårning av fel aktuella utmaningar. Ericsson AB utforskar nya tillvägagångssätt för att hantera sådana komplexa ekosystem.Det här examensarbetet undersöker genomförbarheten och fördelarna med ett flexibelt tillvägagångssätt för design, genom utveckling och karaktärisering av ett konceptbevis för en transceiver-hanterare för höghastighetslänkar. Flexibiliteten realiseras med en mjukvarubaserad kontroller som används för att hantera återställningssignaler och dynamisk rekonfigurering av en transceiver (PHY). Målet med mjukvaruimplementationen är att förenkla feldetektion samt modifikation i realtid, jämfört med en traditionell hårdvarubaserad kontroller. Mjukvaran, som körs på en Nios II soft-coreprocessor, driver styrsignaler och övervakar transceiverns status. Oväntade synkroniseringsförluster hanteras av en dedikerad avbrottshanteringsrutin. Simulationer har gjorts för att testa korrekt interaktion mellan hårdvara och mjukbara. Profilering av mjukvara visar att timingkraven uppfylls (återställningssekvensen tar endast 167 µs). Avslutningsvis har konceptbeviset jämförts med ett likvärdigt hårdvarubaserat system för att utvärdera nackdelarna med introduktionen av Nios II (vad gäller resursanvändningen och effektförbrukningen).Trots lovande resultat är den begränsade detaljnivån i konceptbeviset en tydlig begränsning. Vidare arbete måste göras för att skala upp systemet och generalisera det här nya tillvägagångssättet.
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Vision Based Control for Industrial Robots : Research and implementationMorilla Cabello, David January 2019 (has links)
The automation revolution already helps in many tasks that are now performed by robots. Increases in the complexity of problems regarding robot manipulators require new approaches or alternatives in order to solve them. This project comprises a research in different available software for implementing easy and fast visual servoing tasks controlling a robot manipulator. It focuses on out-of-the-box solutions. Then, the tools found are applied to implement a solution for controlling an arm from Universal Robots. The task is to follow a moving object on a plane with the robot manipulator. The research compares the most popular software, the state-of-the-art alternatives, especially in computer vision and also robot control. The implementation aims to be a proof of concept of a system divided by each functionality (computer vision, path generation and robot control) in order to allow software modularity and exchangeability. The results show various options for each system to take into consideration. The implementation is successfully completed, showing the efficiency of the alternatives examined. The chosen software is MATLAB and Simulink for computer vision and trajectory calculation interfacing with Robotic Operating System (ROS). ROS is used for controlling a UR3 arm using ros_control and ur_modern_driver packages. Both the research and the implementation present a first approach for further applications and understanding over the current technologies for visual servoing tasks. These alternatives offer different easy, fast, and flexible methods to confront complex computer vision and robot control problems.
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Estudo prospectivo e randomizado para avaliar a eficácia e segurança da ablação epicárdica de taquicardia ventricular utilizando cateter irrigado com sensor de contato / Efficacy and safety of epicardial vt ablation using contact force irrigated tip catheter in Chagas diseasePisani, Cristiano Faria 20 February 2019 (has links)
Introdução: O mapeamento e ablação epicárdico é frequentemente necessário em pacientes com cardiopatia não-isquêmica, especialmente pacientes com doença de Chagas. Entretanto, não existem estudos randomizados provando a sua superioridade em comparação a ablação endocárdica exclusiva. Métodos: Foram selecionados 30 pacientes com doença de Chagas encaminhados para ablação de TV sendo randomizados para (1) ablação endocárdica exclusiva e (2) ablação endo e epicárdica combinada. No grupo combinado a ablação era realizada na superfície que se observava os melhores sinais durante TV ou mapeamento de substrato. No grupo endocárdico exclusivo, a ablação era realizada inicialmente na superfície endocárdica apenas e se não existisse cicatriz ou a TV clínica se mantivesse indutível ocorria a continuação da ablação. O objetivo eficácia foi a não reindutibilidade da TV e segurança foi a taxa de complicações do procedimento. Resultados: A maioria dos pacientes eram do sexo masculino, com idade mediana de 67 (58;70) e 58 (43; 66) anos e FEVE de 31,1 ± 11,5% and 41,0 ± 17%, respectivamente. Ocorreu significativamente menos falhas da ablação no grupo combinado (2/15) em comparação ao grupo endocárcico exclusivo (9/126; P=0,21). A ablação epicárdica foi também realizada em nove pacientes do grupo endocárdico exclusivo devido a ausência de cicatriz endocárdica e manutenção da indutibilidade da TV. Não se observou complicações relacionadas ao procedimento. Conclusão: Neste estudo randomizado de ablação epicárdica e endocárdica de TV em pacientes com Doença de Chagas, ocorreu menos insucesso na ablação quando a estratégia combinada endo e epicárdico foi utilizada. Ambas estratégias foram seguras / Background: Epicardial mapping and ablation are frequently necessary for nonischemic cardiomyopathy, especially in Chagas disease patients. We developed this randomized trial to evaluate the efficacy and safety of combined epicardial ablation in Chagas disease patients. Methods: We randomized 30 patients with Chagas disease into an endocardial-only group or a combined epi and endocardial mapping and ablation group. In the combined group, ablation was performed on the surface with optimal signals during mapping. In the endo-only group, ablation was initially performed only on the endo surface despite of nonoptimal signals. The endpoint was efficacy, measured by ventricular tachycardia reinducibility and safety measured by the rate of complications. For endo-only patients, epicardial ablation continuation was allowed after inducibility was assessed following ablation. Results: Most of the patients were male, the median age was 67 (58; 70) and 58 (43; 66) years-old and LVEF was 31.1 ± 11.5% and 41.0 ± 17%, respectively. There was a significant fewer failure for the combined group (2 in 15 patients) comparing to endo only-group ablation (9/15 patients;P=0,021). Epicardial ablation was also performed in nine patients in the endo group after ablation failure due to an absence of endocardial scar and maintenance of VT inducibity. There were no complications related to the epicardial access or ablation. Conclusions: In this randomized trial of epicardial and endocardial VT ablation in Chagas disease, there was less failure of ablation when a combined endo/epi approach was used. Both approaches were safe
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Études de la mise en oeuvre matérielle d’une transmission sans fil combinant retournement temporel et OFDM / Hardware implementation study of a wireless transmission combining time reversal and OFDMKokar, Yvan 15 November 2018 (has links)
L’essor spectaculaire des systèmes de communications sans fil a entrainé une forte augmentation du trafic des données qui ne devrait cesser de croître au cours des prochaines années. La future génération de réseaux cellulaires (5G) doit être capable de supporter cette croissance du trafic, tout en présentant une consommation énergétique réduite par rapport aux réseaux existants. Parmi les différentes technologies étudiées, le retournement temporel (RT) se présente comme un sérieux candidat pour répondre à ces contraintes. En effet, les nombreuses études théoriques sur le sujet ont montré que la combinaison du RT et de l’OFDM possède des performances intéressantes, notamment grâce à ses propriétés de compression temporelle et de focalisation spatiale. Cependant, les hypothèses prises dans les études théoriques ne sont pas toujours compatibles avec la réalisation pratique d’un tel système. L’objectif de ces travaux de thèse est donc de proposer des solutions aux hypothèses non réalistes, afin de les mettre en oeuvre dans la réalisation d’un prototype combinant RT et OFDM dans un contexte MISO. Dans un premier temps, la mise en oeuvre de l’estimation du canal au niveau de l’émetteur et de la synchronisation du système MISO RT-OFDM est étudiée. Ensuite, une solution de calibration au niveau de l’émetteur est proposée pour compenser le caractère non réciproque du canal de propagation vu de la bande de base. L’ensemble de ces solutions ainsi que les propriétés de focalisation du RT sont validés à partir de mesures expérimentales sur le prototype réalisé. Enfin, la mise en oeuvre du premier prototype de modulation spatiale à la réception utilisant le RT est présentée. / The spectacular growth of wireless communications systems has led to a sharp increase in data traffic, which should continue to grow over the next few years. The future generation of cellular networks (5G) must be able to support this growth of traffic, while presenting reduced energy consumption compared to existing networks. Among the different studied technologies, time reversal (TR) is a serious candidate to meet these constraints. Indeed, the numerous theoretical studies on the subject have shown that the combination of TR and OFDM has interesting performance, specifically thanks to its temporal compression and spatial focusing properties. However, the assumptions made in the theoretical studies are not always compatible with the practical implementation of a real system. The objective of this thesis is to propose solutions to unrealistic theoritical hypotheses, in order to implement them in a real hardware prototype combining TR and OFDM in a MISO context. First, the implementation of the channel estimation at the transmitter side, and the synchronization of the MISO TR-OFDM system is studied. Then, a calibration solution at the transmitter is proposed to compensate for the non-reciprocal nature of the baseband propagation channel. All these solutions as well as the focusing properties of TR are validated by experimental measurements using the developed prototype. Finally, the implementation of the first TR prototype of spatial modulation at the receiver side is presented.
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Monitor and manage system and application configuration files at kernel level in GNU/LinuxStanković, Saša January 2015 (has links)
The aim of this study is to investigate if there is a way a computer can accurately and automatically react on altered configuration file(s) with a minimum of resource utilization and by what means the developer(s) of an application can perform a check of the altered configuration file for their application. In a typical GNU/Linux installation the configuration files are literally counted by the thousands, monitoring these files is a task that for the most part exceeds any system administrator's abilities. Each file has its own syntax that needs to be known by the administrator. Either one of these two tasks could give any system administrator nightmares concerning the difficulty level especially when both tasks are combined. The system administrator could attempt to automate the monitoring tasks together with the syntax checking. There are some tools in the repositories of each distribution for monitoring files but none that lets one monitor and take (predefined or user defined) actions based on what the file monitor reports, the type of file and its contents. A complete tool is not presented in this study, merely a proof of concept that monitoring and taking actions especially with version 2.6.13 (or newer) kernel of GNU/Linux with plugins are quite possible with relatively small computer resource. During this study some questions arose that are worth taking into consideration when a complete monitoring tool is to be developed, amongst others they are: add a trusted user, add both textual and graphical user interface, monitor more than one file path. This study was performed on GNU/Linux CentOS 6 distribution, all programming was done in BASH with an effort to minimize used/installed programs.
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Building a low-cost IoT sensor system that recognizes behavioral patterns for collaborative learning - A Proof of ConceptSundblad, Graziella January 2021 (has links)
Since the advent of the Internet, we have been observing a fast-paced development within the computing world. One of the major innovations in recent years is the “Internet of Things”, which brings interconnectedness between devices and humans to unprecedented heights. This technological breakthrough enabled the emergence of a new sub-field within Learning Analytics, Multimodal Learning Analytics, which makes use of several types of data sources to study learning-related processes. As computers and sensors become increasingly cheaper and more accessible, research within this new sub-field grows, yet some gaps remain unexplored. Additionally, there is a research bias toward computer-assisted learning environments, rather than physical ones. At the same time, the current labor market is highly competitive, and possessing profession-related skills is not sufficient to land a job. Besides these skills, there is an increasing demand for social skills, such as communication, teamwork, and collaboration. However, there is a gap between the skills that are trained in an academic setting and the ones that are required by the labor market. Having this background in mind, this work aims at designing and evaluating an IoT sensor system capable of tracking patterns observed under social interactions within a group, and more specifically, in terms of the distance between group members while solving a task. Another important aspect of this study is the system's cost-effectiveness so that it can be employed in a scalable and sustainable manner. To achieve this goal, a multimethodological approach for Design Science Research was adopted, which implied the combination of several methods such as sketching, prototyping, and testing. As a result, this study contributes both to the research area of Multimodal Learning Analytics, and to educational practices.
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A proof-of-concept of the audio tour guide application, SoundTracker, aimed at friends and familyBassam Abdulhamid, Ansam, Jamshaid Gill, Namra January 2018 (has links)
Kontextmedvetenhet kan användas i turistguide applikationer för att bidra användare med information och tjänster. Majoriteten av turistguide applikationer utvecklas vanligtvis för utbildnings eller historiska ändamål. Den här studien presenterar en konceptvalidering av den opublicerade ljuvandrings applikationen "SoundTracker", i syfte att förbättra den. Den nya "SoundTracker" prototypen inriktar sig inte på utbildnings eller historiska ändamål, utan den är inriktad på inspelning, uppspelning, och delning av personliga ljudvandringar med vänner och familj. Konceptvalideringen är begränsad av de definierade forskningsfrågorna i den här uppsatsen. Det handlar i korta drag om en förbättring av noggranheten på de inlästa GPS koordinaterna från en användares position, för att förse användaren med en trevlig användarupplevelse. Dessutom är grafiska användargränssnittet av den originala prototypen förbättrat, och testat genom webb enkäter. Vad gäller delnings funktionaliteten, en test applikation är skapad för att hitta essentiella aspekter som behöver tas hänsyn till i den nya "SoundTracker" prototypen när en användare vill dela ett ljudspår med vänner och familj. Test applikationen testas baserat på samlade svar genom en semi strukturerad interview på människor i åldersgruppen 20-30 år.De erhållna resultaten indikerar på att genom användning av Kalman filter, förbättras noggrannheten på användarens position, vilket resulterar i en ljudvandring med mindre avvikelser jämfört med en GPS-sensor. Vad gäller det förbättrade grafiska användargränssnittet, det var enklare för användarna att förstå den förbättrade prototypen såväl som navigera igenom den, än fallet med den originala prototypen. Användarna finner det även intressant när en delningsfunktion implementeras med designen som diskuteras i det här arbetet. / Context-awareness can be used in tour guide applications in order to provide users with information and services. The majority of tour guide applications are usually developed for educational or historical review purposes. This paper presents a proof-of-concept of the unpublished audio tour guide application, “SoundTracker”, with the aim of improving it. The new “SoundTracker” prototype does not aim for educational or historical review purposes, instead it is aimed for recording, listening and sharing personal audio tour guides with friends and family. The proof-of-concept is limited by the defined research questions found in this paper. In summary, the accuracy of the read-in GPS coordinates of a user’s position is enhanced with Kalman filter, to give an enjoyable user experience. Additionally, the graphical user interface of the original prototype is improved and tested through web-surveys. As for the sharing functionality, a test application is created in order to find what necessary aspects need to be considered in the new "SoundTracker" prototype when a user wants to share a sound-walk with friends and family. The test application is tested based on responses obtained through a semi-structured interview from people in the age of 20-30 years.The obtained results indicate that, with use of Kalman filter, the location accuracy of the user is enhanced, which results in a sound-walk with less deviations compared to location accuracy of only GPS-sensor. Regarding the improved graphical user interface, users found the new "SoundTracker" prototype easier to understand, as well as to navigate through it, than the case in the original prototype. Users also find it interesting when a sharing function is implemented with the design that is discussed in this work.
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