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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

Quality-Impact Assessment of Software Products and Services in a Future Internet Platform

Fotrousi, Farnaz January 2015 (has links)
The idea of a Future Internet platform is to deliver reusable and common functionalities to facilitate making wide ranges of software products and services.  The Future Internet platform, introduced by the Future Internet Public Private Partnership (FI-PPP) project, makes the common functionalities available through so-called Enablers to be instantly integrated into software products and services with less cost and complexity rather than a development from scratch. Quality assessment of software products and services and gaining insights into whether the quality fulfills users’ expectations within the platform are challenging. The challenges are due to the propagation of quality in the heterogeneous composite software that uses Enablers and infrastructure developed by third parties. The practical problem is how to assess the quality of such composite software as well as the impacts of the quality on users’ Quality of Experience (QoE). The research objective is to study an analytics-driven Quality-Impact approach identifying how software quality analytics together with their impact on QoE of users can be used for the assessment of software products and services in a Future Internet platform. The research was conducted with one systematic mapping study, two solution proposals, and one empirical study. The systematic mapping study is contributed to produce a map overviewing important analytics for managing a software ecosystem. The thesis also proposes a solution to introduce a holistic software-human analytics approach in a Future Internet platform. As the core of the solution, it proposes a Quality-Impact inquiry approach exemplified with a real practice. In the early validation of the proposals, a mixed qualitative-quantitative empirical research is conducted with the aim of designing a tool for the inquiry of user feedback. This research studies the effect of the instrumented feedback tool on QoE of a software product. The findings of the licentiate thesis show that satisfaction, performance, and freedom from risks analytics are important groups of analytics for assessing software products and services.  The proposed holistic solution takes up the results by describing how to measure the analytics and how to assess them practically using a composition model during the lifecycle of products and services in a Future Internet platform. As the core of the holistic approach, the Quality-Impact assessment approach could elicit relationships between software quality and impacts of the quality on stakeholders. Moreover, the early validation of the Quality-Impact approach parameterized suitable characteristics of a feedback tool. We found that disturbing feedback tools have negligible impacts on the perceived QoE of software products. The Quality-Impact approach is helpful to acquire insight into the success of software products and services contributing to the health and sustainability of the platform. This approach was adopted as a part of the validation of FI-PPP project. Future works will address the validation of the Quality-Impact approach in the FI-PPP or other real practices.
2

A QoE Model to Evaluate Semi-Transparent Augmented-Reality System

Zhang, Longyu 21 February 2019 (has links)
With the development of three-dimensional (3D) technologies, the demand for high-quality 3D content, 3D visualization, and flexible and natural interactions are increasing. As a result, semi-transparent Augmented-Reality (AR) systems are emerging and evolving rapidly. Since there are currently no well-recognized models to evaluate the performance of these systems, we proposed a Quality-of-Experience (QoE) taxonomy for semi-transparent AR systems containing three levels of influential QoE parameters, through analyzing existing QoE models in other related areas and integrating the feedbacks received from our user study. We designed a user study to collect training and testing data for our QoE model, and built a Fuzzy-Inference-System (FIS) model to estimate the QoE evaluation and validate the proposed taxonomy. A case study was also conducted to further explore the relationships between QoE parameters and technical QoS parameters with functional components of Microsoft HoloLens AR system. In this work, we illustrate the experiments in detail and thoroughly explain the results obtained. We also present the conclusion and future work.
3

Prise en compte de la qualité de l’expérience utilisateur au sein des protocoles de streaming HTTP adaptatifs / Quality of experience in HTTP adaptive streaming protocols

Lavignotte, Antoine 13 May 2014 (has links)
Alors que les services de streaming vidéo (Netflix +YouTube) représentent plus de 50% du trafic web des foyers américains sur leurs lignes fixes, l'expansion de la mobilité (4G LTE et LTEa) et l'arrivée des réseaux du futur (NGN) avec la distinction entre opérateur de réseaux et opérateurs de services, risquent de modifier le modèle économique des fournisseurs de service. Le modèle en Best-effort utilisé actuellement par les services de streaming risque de péricliter dû au coût important lié à ce type de fonctionnement. Il convient donc de réfléchir à un modèle optimisant les flux du service à envoyer en fonction du besoin réel des utilisateurs finaux. L'objectif principal de cette thèse est donc de proposer une solution permettant de prendre en compte la QoE au sein des services de streaming. Dans une première partie de cette thèse, nous mettons en avant le caractère très personnel de la qualité d'expérience lors d'une session de visionnage multimédia. Ceci est réalisé par des tests subjectifs sur une cinquantaine d'utilisateurs. Nous présentons ensuite une architecture permettant la prise en compte de la QoE au sein des protocoles de streaming HTTP adaptatifs (HTTP Live Streaming, DASH ...) afin de prendre des décisions d'adaptation du service non plus sur la bande passante disponible à un instant T, mais sur les attentes implicites de l'utilisateur et ceci d'une manière non intrusive. L‘implémentation d'une preuve du concept est illustrée à travers la création d'un projet open source (http://ipfhas.github.io/) / While streaming video services (Netflix + YouTube} represent more than 50% of US households consumed bandwidth, the growth of mobility (4G LTE + LTEa) and the arrival of 3 next generation networks (NGN) with the distinction between network operator and service operator may change the business model of service providers. The Best-Effort model currently used by streaming services will decrease due to its hight cost. It is therefore necessary to consider a model optimizing the service flow based on real users expectations. The main objective of this thesis is to propose a solution which take into account the QoE in streaming services. In the first art of this thesis, we highlight the very personal nature of the quality of experience during viewing multimedia session. This is achieved by subjective tests on fifty users. Then, we present an architecture for the QoE consideration in HTTP adaptive streaming protocols (HTTP Live Streaming, DASH ...) to make adaptation decisions based on implicit expectations of the user. A proof of concept is illustrated through an open source project (http://ipfhas.github.io/)
4

Investigation of Different DASH Players : Retrieval Strategy & Quality of Experience of DASH

Gunnam, Sri Ganesh Sai January 2018 (has links)
Dynamic Adaptive Streaming over HTTP (DASH) is a convenient approach to transfer videos in an adaptive and dynamic way to the user. Therefore, this system makes best use of the bandwidth available. In this thesis, we investigate Dynamic Adaptive Streaming over HTTP (DASH) based on data collected from the lab experiments and user’s experiments. The objectives include investigation of how three different DASH players behave at different network conditions and up to which limit the players are tolerating the disturbances. We summarized the outcome of lab experiments on DASH at different adverse conditions and checked the lab results with user quality of experience at different adverse conditions to see up to which extent the users could tolerate the disturbances in different DASH players.
5

QoE analysis of diffrenet DASH players in adverse network conditions

Pulagam, Sai January 2018 (has links)
Streaming multimedia over the Internet is omnipresent but still in its infancy, specifically when it comes to theadaptation based on bandwidth/throughput measurements, clients competing for limited/shared bandwidth, and thepresence of a caching infrastructure. Nowadays the streaming infrastructure is existing over-the-top (OTT).Interestingly, these services are all delivered over-the-top of the existing networking infrastructure using the HypertextTransfer Protocol (HTTP) which resulted in the standardization of MPEG Dynamic Adaptive Streaming over HTTP(DASH).Video traffic is over 80% of the total internet traffic. Since Dynamic adaptive streaming over HTTP hasemerged it has a popular technique for video streaming on the internet. DASH allows the video player to adapt thebitrate according to the network conditions. DASH streaming client receives a manifest file, downloaded the referredvideo segments over HTTP, and play them back seamlessly emulated video streaming. This introduces latency of atleast one segment duration which decreases the quality of the user experience. In order to improve users over allQuality of Experience(QoE) a large number of adaptaion schemes were introduced to DASH.With such an importance of QoE on DASH, this thesis work investigates user acceptability of different DASHplayers. These players are exposed to different network conditions and the user analysis is given for each of thestreaming dash video for each player. The results of this thesis work include the analysis of the user rating for threedifferent players (Dash.js, GPAC and Shaka). The conclusion of this thesis is given by the quality of experience of thevideo streaming by the users which concludes that the Shaka player is preferred by the users compared to the othertwo players.
6

A Quantitative Study of Quality of Experience (QoE) for Decreasing and Increasing Network Performance.

Dhungana, Ramesh, Shahi, Deepak January 2011 (has links)
Currently, user satisfaction is becoming one of the major concerns for the service provider in accommodating user demand. This paper evaluates the user’s perception (Quality of Experience, QoE) of the increasing and decreasing response times (Quality of Service, QoS), in particular a login to web login page by the implementation of Mean Opinion Score (MOS). By comparing the results to user perception of web login performance, we show that the users perceive web login for increasing and decreasing RTs in different ways. So, we conduct interview among specific users applying increased and decreased RTs in particular web login to rank the users satisfaction level. Study of the two results for RTs of the web login page is presented.
7

On the Incorporation of Quality of Experience (QoE) in Mobile Networks : A technical, regulatory and business analysis

Martinez Ballesteros, Luis Guillermo January 2017 (has links)
Mobile operators face a scenario characterised by new challenges such as growing data consumption, a slowdown in subscriber growth and reduced revenues due to the success of OTT providers. To remain competitive, mobile operators must offer affordable services and think on strategies to retain current customers. Quality of Experience (QoE) is a well-established methodology for measuring and understanding the overall level of customer satisfaction with a service and has been presented as a way to improve telecommunication services. Even though QoE can be used to solve problems such as customer loyalty and optimisation of network resources in mobile networks, there is a great lack of knowledge on how mobile operators can take advantage of QoE and its potential benefits. This thesis explores the incorporation of QoE in mobile networks to improve their service offering from a technical, regulatory and business perspective.The technical level focuses on the definition of the mechanism to integrate QoE in the operation of mobile networks. The second part of this study has been focused on the regulatory framework on Net Neutrality. Finally,the third part of this thesis focuses on the identification of potential business scenarios and models based on the incorporation of QoE in mobile networks. An important conclusion is that due to the nature of the challenges faced by the mobile industry, a QoE analysis cannot be limited to a technical discussion. A technical solution can be the first step to the first step to overcoming industry challenges. However, it is important that a technical decision comes along with an informed analysis of the regulatory conditions and the business implications of the proposed solution. On the other hand, mobile operators require new methods that integrate technical, market and business considerations to improve their service offer. A method analysed in this dissertation is a Customer Experience Management (CEM) platform. Given the technical, regulatory and business factors covered in this thesis, a CEM platform can be used by mobile operators to make a better use of QoE in their business operation. / Mobiloperatörer möter ett scenario som kännetecknas av en ökande trend inom dataförbrukning, tecken på en avmattning i abonnenttillväxten, en en minskning av de traditionella intäkter på grund av framgången med OTT leverantörer. Dessutom, mobila användare har gott om alternativ för att ändra tjänsteleverantören. I det här fallet måste mobiloperatörer förbli konkurrenskraftiga baseras både på pris och deras abonnenter tillfredsställelse. Kvalitet Erfarenhets (QoE) införlivande i mobilnät kan vara ett av alternativen för att möta vissa mobilbranschen utmaningar som omfattar tekniska, kommersiella och marknadsnivå. QoE möjliggör en bredare och mer övergripande förståelse av användarnas erfarenheter med utförandet av applikationer, tjänster och nätverk, samtidigt som kompletterar traditionella techno-centric begrepp som Quality of Service(QoS). Händelse om användningen av QoE data har föreslagits som ettsätt att lösa problem som optimering av nätverksresurser och kundomsättning upplevs av mobiloperatörer, finns det fortfarande en lucka på hur man utnyttjar QoE och dess potentiella fördelar i ramen för mobilnät. Således är den övergripande inriktningen av denna avhandling på att analysera hur mobiloperatörer kan integrera QoE feedback för att förbättra sin serviceerbjudande.Men på grund av arten av de utmaningar som den mobila industrin står inför, denna analys kan inte begränsas till en teknisk nivå diskussion. även hitta en teknisk lösning skulle kunna vara det första steget för att övervinna utmaningarna på marknaden, är det viktigt att ett tekniskt beslut kommer tillsammans med en välgrundad analys av de regulatoriska förutsättningarna för att genomförandet och affärs konsekvenserna av den föreslagna lösningen.Så kan en skådespelare intresserad av genomförandet av det föreslagna i dennaavhandling mekanism har fler verktyg för ett välgrundat beslut fattandet. På teknisk nivå, fokuserar denna uppsats på identifiering av teknisk mekanismför att införliva QoE i mobilnätet. Sedan vår analys kretsar kring identifieringen av regelverket om nätneutralitet och dess potentiella inverkan på genomförandet av den föreslagna mekanismen för införliva QoE i mobilnät. Slutligen, och letar efter en helhetssyn på QoE frågan, erbjuder vi en analys av konsekvenserna av att införliva QoE för hela mobilnät ekosystemet och intressenterna längs hela värdenätverket. / <p>QC 20161229</p> / Quality of Experience: A Techno-economic Analysis / Quality of Experience and Net Neutrality
8

Image Quality Assessment of 3D Synthesized Views / Évaluation de la qualité des images obtenues par synthèse de vues 3D

Tian, Shishun 22 March 2019 (has links)
Depth-Image-Based Rendering (DIBR) est une technologie fondamentale dans plusieurs applications liées à la 3D, telles que la vidéo en mode point de vue libre (FVV), la réalité virtuelle (VR) et la réalité augmentée (AR). Cependant, l'évaluation de la qualité des vues synthétisées par DIBR a également posé de nouveaux problèmes, car ce processus induit de nouveaux types de distorsions, qui sont intrinsèquement différentes des distorsions provoquées par le codage vidéo. Ce travail est destiné à mieux évaluer la qualité des vues synthétisées par DIBR en multimédia immersif. Au chapitre 2, nous proposons deux métriques complètements sans référence (NR). Le principe de la première métrique NR NIQSV consiste à utiliser plusieurs opérations morphologiques d’ouverture et de fermeture pour détecter et mesurer les distorsions, telles que les régions floues et l’effritement. Dans la deuxième métrique NR NIQSV+, nous améliorons NIQSV en ajoutant un détecteur de “black hole” et une détection “stretching”.Au chapitre 3, nous proposons deux métriques de référence complète pour traiter les distorsions géométriques à l'aide d'un masque de désocclusion et d'une méthode de correspondance de blocs multi-résolution. Au chapitre 4, nous présentons une nouvelle base de données d'images synthétisée par DIBR avec ses scores subjectifs associés. Ce travail se concentre sur les distorsions uniquement induites par différentes méthodes de synthèse de DIBR qui déterminent la qualité d’expérience (QoE) de ces applications liées à DIBR. En outre, nous effectuons également une analyse de référence des mesures d'évaluation de la qualité objective de pointe pour les vues synthétisées par DIBR sur cette base de données. Le chapitre 5 conclut les contributions de cette thèse et donne quelques orientations pour les travaux futurs. / Depth-Image-Based Rendering (DIBR) is a fundamental technology in several 3D-related applications, such as Free viewpoint video (FVV), Virtual Reality (VR) and Augmented Reality (AR). However, new challenges have also been brought in assessing the quality of DIBR-synthesized views since this process induces some new types of distortions, which are inherently different from the distortions caused by video coding. This work is dedicated to better evaluate the quality of DIBRsynthesized views in immersive multimedia. In chapter 2, we propose a completely No-reference (NR) metric. The principle of the first NR metrics NIQSV is to use a couple of opening and closing morphological operations to detect and measure the distortions, such as “blurry regions” and “crumbling”. In the second NR metric NIQSV+, we improve NIQSV by adding a “black hole” and a “stretching” detection. In chapter 3, we propose two Fullreference metrics to handle the geometric distortions by using a dis-occlusion mask and a multi-resolution block matching methods.In chapter 4, we present a new DIBR-synthesized image database with its associated subjective scores. This work focuses on the distortions only induced by different DIBR synthesis methods which determine the quality of experience (QoE) of these DIBR related applications. In addition, we also conduct a benchmark of the state-of-the-art objective quality assessment metrics for DIBR-synthesized views on this database. The chapter 5 concludes the contributions of this thesis and gives some directions of future work.
9

On test principles for a QoE evaluation using real services

Kurze, Albrecht, Eibl, Maximilian 16 January 2017 (has links) (PDF)
We report on our experiences from two user studies (lab experiments) with nearly 300 participants for QoE evaluation using real mobile services and devices in our WiFi network emulation testbed. We briefly introduce our principles for integrating real services in these studies: how we selected relevant services, how we investigated their testability and how we tested them with high efficiency.
10

On test principles for a QoE evaluation using real services: overview on methodology and challenges for defining test principles

Kurze, Albrecht, Eibl, Maximilian 16 January 2017 (has links)
We report on our experiences from two user studies (lab experiments) with nearly 300 participants for QoE evaluation using real mobile services and devices in our WiFi network emulation testbed. We briefly introduce our principles for integrating real services in these studies: how we selected relevant services, how we investigated their testability and how we tested them with high efficiency.

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