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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.
441

Développement et évaluation des paramètres quantitatifs de l’IRM de la prostate / Development and evaluation of quantitative parameters of prostate MRI

Hoang Dinh, Au 10 November 2015 (has links)
L'objectif de cette thèse est de développer et d'évaluer des paramètres quantitatifs de l'IRM de la prostate en discriminant les cancers de score de Gleason (GS) ≥7. Nous supposons que les paramètres quantitatifs de l'IRM pourraient aider à standardiser le diagnostic, et à diminuer la variation inter-lecteur et/ou inter-institution du diagnostic du cancer de la prostate. Cette thèse est divisée en trois chapitres. Le premier chapitre, intitulé « IRM T2 quantitatif de la prostate », est une étude rétrospective sur une base de données des patients avant prostatectomie radicale. Le deuxième chapitre, intitulé « IRM multiparamétrique quantitative de la prostate », est aussi une étude rétrospective avant prostatectomie radicale. Le troisième chapitre, intitulé « Élastographie IRM de la prostate par voie trans-périnéale» est une étude expérimentale. Notre première étude montre que le T2 est robuste sur les machines de constructeurs différents. Le T2 est un prédicteur significatif, mais de faible performance, d'agressivité du cancer de la prostate à 3T. Notre deuxième étude montre que la combinaison du 10ème centile de l'ADC avec le Time-topeak (TTP) améliore la performance du diagnostic, et ce modèle est lui aussi robuste entre des machines de constructeurs différents. Notre troisième étude montre les résultats préliminaires sur l'élasticité de la prostate. Ces résultats montrent que l'élastographie IRM de la prostate en haute fréquence d'excitation (>100 Hz) par voie trans-périnéale est faisable. L'élastographie pourrait à l'avenir être intégrée à l'IRM multiparamétrique quantitative pour améliorer la performance de diagnostic / The purpose of this thesis is to develop and evaluate the quantitative methods of multiparametric MRI of prostate in discriminating Gleason score (GS) ≥7 cancers. We suppose that the quantitative parameter of MRI could help standardizer the diagnostic, reduce the inter-lecture and/ or inter-institution variation in diagnostic of prostate cancer. This thesis is divided into three chapters. The firs chapter, entilted « Quantitative T2 MRI of prostate » is a retrospective study on a database of prostate cancer patients before radical prostatectomy. The second chapter, entilted « Multi-parametric Quantitative MRI of prostate » is also a retrospective study before radical prostatectomy. The third chapter, entitled « MR elastography of prostate by transperineal approach », is an experimental study. Our first study shows that T2 value is robust between machines of different constructors. T2 value is significant predictor, but of weak performance, of aggressively cancer of prostate at 3T. Our second study shows that the combination of ADC_10th percentile with Time-to-peak (TTP) improved the diagnosis performance, and this model is also robust between two machines of different constructors. Our third study shows the initial results on elasticity of the prostate. These results show that MRI elastography of prostate at high excitation frequency (>100 Hz) by trans-perineale approach was feasible. The elastography may, in the future, be integrated in quantitative multi-parametric MRI to improve the diagnosis performance
442

Low Power Test Methodology For SoCs : Solutions For Peak Power Minimization

Tudu, Jaynarayan Thakurdas 07 1900 (has links) (PDF)
Power dissipated during scan testing is becoming increasingly important for today’s very complex sequential circuits. It is shown that the power dissipated during test mode operation is in general higher than the power dissipated during functional mode operation, the test mode average power may sometimes go upto 3x and the peak power may sometimes go upto 30x of normal mode operation. The power dissipated during the scan operation is primarily due to the switching activity that arises in scan cells during the shift and capture operation. The switching in scan cells propagates to the combinational block of the circuit during scan operation, which in turn creates many transition in the circuit and hence it causes higher dynamic power dissipation. The excessive average power dissipated during scan operation causes circuit damage due to higher temperature and the excessive peak power causes yield loss due to IR-drop and cross talk. The higher peak power also causes the thermal related issue if it last for sufficiently large number of cycles. Hence, to avoid all these issues it is very important to reduce the peak power during scan testing. Further, in case of multi-module SoC testing the reduction in peak power facilitates in reducing the test application time by scheduling many test sessions parallelly. In this dissertation we have addressed all the above stated issues. We have proposed three different techniques to deal with the excessive peak power dissipation problem during test. The first solution proposes an efficient graph theoretic methodology for test vector reordering to achieve minimum peak power supported by the given test vector set. Three graph theoretic problems are formulated and corresponding algorithms to solve the problems are proposed. The proposed methodology also minimizes average power for the given minimum peak power. Further, a lower bound on minimum achievable peak power for a given test set is defined. The results on several benchmarks show that the proposed methodology is able to reduce peak power significantly. To address the peak power problem during scan test-cycle (the cycle between launch and capture pulse) we have proposed a scan chain reordering technique. A new formulation for scan chain reordering as TSP (Traveling Sales Person) problem and a solution is proposed. The experimental results show that the proposed methodology is able to minimize considerable amount of peak power compared to the earlier proposals. The capture power (power dissipated during capture cycle) problem in testing multi chip module (MCM) is also addressed. We have proposed a methodology to schedule the test set to reduce capture power. The scheduling algorithm consist of reordering of test vector and insertion of idle cycle to prevent capture cycle coincidence of scheduled cores. The experimental results show the significant reduction in capture power without increase in test application time.
443

Slutet gott allting gott? Peak-end rule och användarupplevelsen av ett webbformulär

Hussein, Hadi, Lindström, Rebecca January 2021 (has links)
Det ställs allt högre krav på interaktiva system idag. Centralt är att de ska tillgodose användarens behov – inte minst användarens känslor och upplevelser. Enligt tidigare forskning kan starka känslomässiga ögonblick under ett händelseförlopp och upplevelsen av dess slut påverka hur vi bedömer en tidigare upplevelse (Kahneman, Fredrickson, Schreiber & Redelmeier, 1993; Redelmeier, Katz & Kahneman, 2003). Syftet med denna studie var att undersöka huruvida peak-end rule har en effekt på den retrospektiva användarupplevelsen av ett digitalt gränssnitt. Detta genom att jämföra två versioner av en prototyp vars interaktion var avsedd att efterlikna ett formulär på en webbsida. De två versionerna var identiska förutom att slutet manipulerades i syfte att framkalla ett positivt slut i den ena versionen och ett neutralt slut i den andra versionen. Totalt 22 deltagare skattade sin generella användarupplevelse efter att ha interagerat med varje version. Därefter svarade de på frågor rörande val av preferens samt upplevd ansträngning. Resultatet visade att peak-end rule hade en signifikant påverkan på val av preferens. Däremot fanns inget stöd som talar för att den totala användarupplevelsen eller upplevda ansträngningen påverkades av slutets utformning. Detta innebär att slutet av en interaktion kan påverka användarupplevelsen i viss mån men att det samtidigt råder en viss tvetydighet kring resultatet. Studerandet av peak-end rule är ännu i en tidig fas inom sammanhanget människa-datorinteraktion. Det krävs således vidare forskning för bättre förståelse om dess effekt för användarupplevelse av interaktiva system. / Today there are ever higher demands on interactive systems. Central is that they should meet the user's needs – not least the user's feelings and experiences. According to previous research, strong emotional moments during the course of events and the experience of its end can affect how we assess previous experiences (Kahneman, Fredrickson, Schreiber & Redelmeier, 1993; Redelmeier, Katz & Kahneman, 2003). The purpose of this study was to investigate whether peak-end rule has an effect on the retrospective user experience of a digital interface. This is done by comparing two versions of a prototype whose interaction was intended to resemble a form on a web page. The two versions were identical except that the ending was manipulated in one version in order to evoke a positive ending and a neutral ending in the other version. A total of 22 participants rated their overall user experience after interacting with each version. They then answered questions regarding the choice of preference and perceived effort. The results showed that the peak-end rule had a significant influence on the choice of preference. On the other hand, there was no evidence to suggest that the overall user experience or perceived effort was affected by the design of the end. This means that the end of an interaction can affect the user experience to a certain extent, but that at the same time there is a certain ambiguity about the result. The study of peak-end rule is still in an early phase within the field of human-computer interaction. Further research is thus required for a better understanding of its effect on the user experience of interactive systems.
444

Impact of Passive Range of Motion Exercises and Stretching in Knee Osteoarthritis Pain during Walking

Ottonello, Dominique Marchelle 05 August 2020 (has links)
No description available.
445

Charging Towards Savings : How Utility Tariffs and Consumtion Profiles Impact the Profitability of BTM Battery Storage Systems / Hur Eltariff och Konsumtionsprofil Påverkar Lönsamheten i Batterilagring Bakom Elmätaren

Aston, Daniel, Lindström, Gustav January 2023 (has links)
Battery Storage Systems (BESS) installed Behind the Meter (BTM) can provide demand management services, reducing electricity costs and enhancing overall electricity system stability. BTM BESS can also imporve self-consumption obtained with distributed generation assets like solar photovoltaics. This study examines the influence on value creation from consumption patterns and utility tariffs. Using Swedish and UK tariffs and a set of consumption profiles, the study determines the optimal BESS configuration and conducts simulations to assess profability through Net Present Value. Comparative analysis reveals the impact of utility tariffs and consumption profiles on profitablility. Projected BESS cost levels for 2030 and 2050 are used to evaluate expected future profitability.  The findings indicate that utility tariff has a stronger influence on BTM BESS profitability than consumption profile. Energy arbitrage creates most of the value, depending more on tariff structure than consumption pattern. However, with higher demand charges, the consumtion profile becomes more important as the relative value of peak shaving increases. Two sensitivity analyses have been performed. The first shows that NPVs are affected by decreased electricity price variability, emphasising the need for accurate long-term price forcasts. The second shows that existing electricity consumption forecasting techniques prove sufficient for effective peak shaving.  In conclusion, this research inderscores the significance of utility tariffs and consumption profiles in determining BTM BESS profitability. Energy arbitrage dominates value creation, while peak shaving gains importance with higher demand charges. Accurate long-term price forecasts are crucial for assessing BTM BESS profitability, and existing consumption forecasting techniques are suitable for peak shaving. / Batterilagring installerad bakom elmätaren kan optimera en fastighets elkonsumtion för att reducera elkostnader samt förbättra stabiliteten i elsystemet som helhet. Den här studien undersöker faktorer som påverkar värdeskapande genom energiarbitrage och peak shaving, inklusive konsumtionsprofiler och eltariffer. Studien undersöker även om det går att uppnål önsamhet under nuvarande och framtida prisnivåer för batterilagring. Studien utgår ifrån svenska och brittiska eltariffer samt fem konsumtionsprofiler, och fastställer den mest optimala konfigurationen av batterilagring genom optimering. Därefter jämförs lönsamheten genom nettonuvärde-analys för att dra slutsatser om hur eltariff och konsumtionsprofil påverkar lönsamhet. Studien visar att lönsamhet för batterilagring bakom mätaren beror mer på eltariff än konsumtionsprofil. Detta eftersom mest värde skapas genom energiarbitrage som är mindre beroende av konsumtionsprofil men direkt beroende av variationer i elpriset. Med högre effektavgifter ökar lönsamhetens beroende av konsumtionsprofilen då det relativa värdet av peak shaving höjs. En känslighetsanalys visar på en stark korrelation mellan värdet av energiarbitrage och variationer i elpriset, vilket visar vikten av långsiktiga prognoser av elprisets volatilitet. Befintliga tekniker för prognostisering av elkonsumtion har tillräcklig noggrannhet för effektivpeak shaving. Sammanfattningsvis visar studien hur eltariff och konsumtionsprofil påverkar lönsamheten för batterilagring installerad bakom elmätaren. Majoriteten av värdet skapas genom energiarbitrage för svenska och brittiska tariffer. Med högre effektavgifter ökar betydelsen av peak shaving. Dessutom betonar studien vikten av långsiktiga prognoser av elprisvolatilitet vid utvärderingen av lönsamheten för investeringar i batterilagring bakom mätaren.
446

Regulated Feedback Networks with Degradation

Addai, Obeng A. 05 October 2015 (has links)
No description available.
447

Effekttoppskapning med styrsystem från Enequi : En analys av effektavgiftbesparing och produktprestanda / Peak power shaving with control system from Enequi : An analysis of power fee savings and product performance

Oskarsson, Ebba, Lönnqvist, Tim January 2024 (has links)
I takt med ökad elektrifiering i samhället står elnätet inför en problematik med kapacitetsbrist. Med anledning av detta finns ett behov av att utveckla en mer flexibel och effektiv användning av elnätet. En del i detta är införandet av effekttariffer, vilket ska skapa incitament för elkunder att sprida ut sin elanvändning och på så sätt avlasta elnätet. Företaget Enequi tillhandahåller ett system med smart styrning och batterilagring vilket kan utföra effekttoppskapning i syfte att reducera effektavgiften. I denna studie granskas två bostäder, belägna i Partille och Sollentuna, vilka båda har ett styrsystem från Enequi installerat. Syftet är att undersöka hur styrningen bidrar till en förändring i effektavgiften hos de båda bostäderna, samt att bedöma systemets prestanda. Resultatet från Partille visar att ägaren under de åtta månaderna systemet varit i drift sparar 259 kronor på effektavgiften, medan ägaren i Sollentuna under tolv månader sparar 865 kronor. Analysen av systemets prestanda visar också att systemet presterar mest optimalt när egenproducerad el är tillgänglig. Systemet bidrar till nätnytta genom att flytta lasten i bostaden från högt belastade timmar till lågt belastade. Brister som har identifierats i prestandan inkluderar problematik med förhöjda effektavgifter under vissa månader. Slutsatsen är att systemet presterar funktionellt trots vissa brister och att det är möjligt att göra besparingar på effektavgiften över tid.
448

Mechanism of orthotic therapy for the painful cavus foot deformity

Najafi, Bijan, Wrobel, James, Burns, Joshua January 2014 (has links)
BACKGROUND:People who have extremely high arched feet or pes cavus often suffer from substantial foot pain. Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear. It is generally thought that one of the primary functions of CFO is redistributing abnormal plantar pressures. This study sought to identify variables associated with pain relief after CFO intervention.METHODS:Plantar pressure data from a randomized controlled trial of 154 participants with painful pes cavus were retrospectively re-analyzed at baseline and three month post CFO intervention. The participants were randomized to a treatment group given CFO or a control group given sham orthoses.RESULTS:No relationship between change in pressure magnitude and change in symptoms was found in either group. However, redistribution of plantar pressure, measured with the Dynamic Plantar Loading Index, had a significant effect on pain relief (p=0.001). Our final model predicted 73% of the variance in pain relief from CFO and consisted of initial pain level, BMI, foot alignment, and changes in both Dynamic Plantar Loading Index and pressure-time integral.CONCLUSION:Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures. Results of this study add to the growing body of literature providing mechanistic support for CFO providing pain relief in painful foot conditions. The proposed model may assist in better designing and assessing orthotic therapy for pain relief in patients suffering painful cavus foot deformity.TRIAL REGISTRATION:Randomized controlled trial: ISRCTN84913516
449

Development of a high speed, high efficiency LA-ICP-MS interface

Douglas, David N. January 2013 (has links)
Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) is now a well established analytical technique used to sample solid materials and determine their elemental composition. Two areas that are becoming increasingly important, and for which LA-ICP-MS is a key tool, are bio-imaging and the analysis of micro-particulates. However, current instrumental designs limit the practicality of the technique for these applications. This study investigates the development of a high speed, high efficiency LA-ICP-MS interface through modelling of the flow dynamics of a newly designed laser ablation cell and experimental investigation of single laser pulse response. Through this work the Sniffer-Dual Concentric Injector interface was realised. This interface reduced particle residence times within the laser cell and transport tubing. The interface was also used to investigate turbulence related aerosol dispersion within the ICP and potential designs to overcome this. The resulting design yields an interface with improved sensitivity and reduced aerosol dispersion such that a lower limit of detection is achieved, important when considering the mass of analyte in a single cell or micro-particulate, compared to existing designs. Thus the interface can be used to improve image spatial resolution as the ablation spot size, and thus pixel information, can be reduced; and also reduces total analysis time. The calibration technique Laser Ablation of a Sample In Liquid (LASIL) was also investigated as a means of calibration for solid samples. The investigation lead to the development of LASIL in a droplet, a technique that can be used to calibrate solid samples when a matrix matched standard is unavailable. The mechanism of the technique resulted in an improved laser-energy sample coupling efficiency and a reduction in the liquid to ablated mass ratio, thus decreasing sampling time. As the technique captures the ablated particulate in solution, post chemistry techniques can be used to remove analyte interferences.
450

Optimization of a Household Battery Storage : The Value of Load Shift

Boström, Christoffer January 2016 (has links)
Sweden’s energy system is facing major changes in the near future in order to reducecarbon emissions and to switch to sustainable energy sources. PV systems havebecome a sensible alternative for homeowners that want to be a part of this changeand at the same time reduce the cost of their electricity bill. To further improve theutilization of their PV system and to handle the intermittent nature of solar power,battery storages have become an interesting system complement. This thesisinvestigates how batteries can provide smart services; load shift and peak price energyutilization to a household. This is done by developing an optimized battery algorithmmodel that can provide these smart services which is compared to a simple batteryalgorithm. The results show that the developed battery optimization model works asintended. It performs both load shift and peak price energy utilization. The economicanalysis shows that the most profitable PV system and battery configuration is a 20kW PV system with a 5 kWh battery. The system has an internal rate of return, IRR,of 2.3% which does not reach Vattenfall’s weighted average cost of capital, WACC, at7%. The results also show that the battery cost is an important factors for a system'sprofitability. A larger battery system is more expensive and the increased yield doesnot cover the increased cost. Further research is needed to implement the optimizedbattery as a functional application since the model has access to a perfect forecast andthus a method for forecasting PV production and load profile of the household arecrucial to get similar results.

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