933 research outputs found

    Assessing quality of experience of IPTV and video on demand services in real-life environments

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    The ever growing bandwidth in access networks, in combination with IPTV and video on demand (VoD) offerings, opens up unlimited possibilities to the users. The operators can no longer compete solely on the number of channels or content and increasingly make high definition channels and quality of experience (QoE) a service differentiator. Currently, the most reliable way of assessing and measuring QoE is conducting subjective experiments, where human observers evaluate a series of short video sequences, using one of the international standardized subjective quality assessment methodologies. Unfortunately, since these subjective experiments need to be conducted in controlled environments and pose limitations on the sequences and overall experiment duration they cannot be used for real-life QoE assessment of IPTV and VoD services. In this article, we propose a novel subjective quality assessment methodology based on full-length movies. Our methodology enables audiovisual quality assessment in the same environments and under the same conditions users typically watch television. Using our new methodology we conducted subjective experiments and compared the outcome with the results from a subjective test conducted using a standardized method. Our findings indicate significant differences in terms of impairment visibility and tolerance and highlight the importance of real-life QoE assessment

    MyAngel: An Auditory Android Mobile Application for Emergency with Location-based Service

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    This study is aimed to propose an emergency framework with the development of an auditory android mobile application with location-based service called MyAngel. MyAngel app serves the functionality as a location based notification tool and annoyance producer by the high frequency noise for attention distraction purpose by using only a single emergency alert button. Due to the steep increment of crime rate especially on the robberies, the outlook of the country is grim and the number of innocent victim is also increasing. Thus, this study is addressing the problem on difficulty in getting immediate assistance from the outsiders as well as the insufficient self-defense techniques of the robbery victim to fight against the robbers with or without firearms. To develop the MyAngel app, several methodologies have been conducted. The high frequency noise and location based services (LBS) related data have been collected through online sources and further analysis on the information gathered have been performed through literature survey. Besides, pre-survey questionnaires were conducted to the citizens in Selangor and Kuala Lumpur to understand their opinions on the robbery issues. The interview session was also being carried out with one of the robbery victim to understand the victim‟s needs during emergencies. In addition, another interview session was done with the Operational Inspector in Selangor to investigate if the noise criterion has been considered and proposed within the Royal Malaysian Police (PDRM). The results indicate that all the survey respondents and interviewed robbery victim agreed with the increase of robbery rate and they had showed their demand on the development of MyAngel mobile application. Moreover, the noise concept has not been adopted in PDRM yet. Thus, it will be included in MyAngel app as one of the main functions which will be integrated with the function of LBS to meet the requirement of the users

    MyAngel: An Auditory Android Mobile Application for Emergency with Location-based Service

    Get PDF
    This study is aimed to propose an emergency framework with the development of an auditory android mobile application with location-based service called MyAngel. MyAngel app serves the functionality as a location based notification tool and annoyance producer by the high frequency noise for attention distraction purpose by using only a single emergency alert button. Due to the steep increment of crime rate especially on the robberies, the outlook of the country is grim and the number of innocent victim is also increasing. Thus, this study is addressing the problem on difficulty in getting immediate assistance from the outsiders as well as the insufficient self-defense techniques of the robbery victim to fight against the robbers with or without firearms. To develop the MyAngel app, several methodologies have been conducted. The high frequency noise and location based services (LBS) related data have been collected through online sources and further analysis on the information gathered have been performed through literature survey. Besides, pre-survey questionnaires were conducted to the citizens in Selangor and Kuala Lumpur to understand their opinions on the robbery issues. The interview session was also being carried out with one of the robbery victim to understand the victim‟s needs during emergencies. In addition, another interview session was done with the Operational Inspector in Selangor to investigate if the noise criterion has been considered and proposed within the Royal Malaysian Police (PDRM). The results indicate that all the survey respondents and interviewed robbery victim agreed with the increase of robbery rate and they had showed their demand on the development of MyAngel mobile application. Moreover, the noise concept has not been adopted in PDRM yet. Thus, it will be included in MyAngel app as one of the main functions which will be integrated with the function of LBS to meet the requirement of the users

    Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 274)

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    This bibliography lists 128 reports, articles, and other documents introduced into the NASA scientific and technical information system in July 1985

    A survey on Quality of Experience of Virtual and Augmented Reality environments

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    Οι εφαρμογές εικονικής και επαυξημένης πραγματικότητας αποτελούν μια νέα και πολλά υποσχόμενη τεχνολογία, με εφαρμογές στην ιατρική, την εκπαίδευση, τα βιντεοπαιχνίδια, το ηλεκτρονικό εμπόριο και πολλές άλλες. Αυτή η τεχνολογία θέτει μια νέα πρόκληση για τους σχεδιαστές εφαρμογών, καθώς και για τους παρόχους υπηρεσιών δικτύου, επειδή είναι εντατική ως προς τους απαιτούμενους πόρους ώστε να είναι σε θέση να παρέχει συναρπαστική εμπειρία στους χρήστες της. Αυτή η πρόκληση γίνεται ακόμη πιο δύσκολη στα δίκτυα κινητής τηλεφωνίας, λόγω παραγόντων που είναι δύσκολο να μοντελοποιηθούν και να προβλεφθούν, όπως η κινητικότητα, η στρατηγική μεταβίβασης και η κατανομή πόρων. Αυτή η διπλωματική φιλοδοξεί να παράσχει μια ανασκόπηση των τεχνικών και μεθόδων εκτίμησης της ποιότητας της εμπειρίας (QoE) και των μεθόδων που έχουν αναπτυχθεί γύρω από αυτές τις εφαρμογές. Στην πρώτη ενότητα, εξετάζουμε τις στρατηγικές παροχής QoE για εφαρμογές εικονικής πραγματικότητας. Αυτή η ενότητα εξετάζει αρκετές περιπτώσεις εφαρμογών εικονικής πραγματικότητας, όπως ένα λογισμικό προσομοίωσης βαρέων μηχανημάτων, μια εκπαιδευτική εφαρμογή και άλλες ψηφιακές εφαρμογές εμβύθισης. Το εύρος και η ποικιλία των εφαρμογών και των μεθόδων εκτίμησης της ποιότητας της εμπειρίας οδηγούν σε αντικρουόμενα συμπεράσματα σχετικά με τις μεθόδους αξιολόγησης QoE. Στην επόμενη ενότητα αναφερόμαστε σε εφαρμογές επαυξημένης πραγματικότητας, και πάλι με μια αναφορά σε μια μεγάλη ποικιλία εφαρμογών, όπως ένας βοηθός επαυξημένης πραγματικότητας, βιντεοπαιχνίδια επαυξημένης πραγματικότητας και άλλες ψηφιακές εφαρμογές. Τα συμπεράσματα σε αυτήν την ενότητα είναι πιο ισχυρά και τα συναισθήματα των ανθρώπων μπορούν να σχηματίσουν πιο ουσιαστικά πορίσματα. Στην τελευταία ενότητα διερευνούμε την QoE σε εφαρμογές εικονικής και επαυξημένης πραγματικότητας για κινητές συσκευές και κινητά δίκτυα. Σε αυτό το μέρος ασχολούμαστε με πιο τεχνικές πτυχές όπως η διαχείριση της κινητικότητας, οι στρατηγικές μεταβίβασης και οι αλγόριθμοι κατανομής πόρων και ο αντίκτυπος που έχουν αυτοί στην εμπειρία των χρηστών.Virtual and augmented reality applications constitute a new and promising technology, with applications in medicine, education, gaming, e-commerce and many more. This technology poses a new challenge to application designers, as well as network service providers, because it is resource intensive in order to be able to provide the immersive experience to its users. This task becomes even more challenging in mobile networks, due to factors that are difficult to be modeled and predicted, such as mobility, handoff strategy and resource allocation. This thesis aspires to provide a review of Quality of Experience (QoE) estimation and provision techniques and methods that have been developed around these applications. In the first section, we review QoE provisioning strategies for virtual reality applications. This section examines some corner cases of augmented reality applications, such as a heavy machinery simulation software, an educational application, and many digital immersive applications. The scope and diversity of applications and implementation methods lead to some conflicting conclusions in relation to QoE evaluation methods. In the next section we refer to augmented reality applications, again with a reference to a wide variety of applications such as an augmented reality task assistant, augmented reality video games and digital immersive applications. The conclusions in this section are more robust and peoples’ feelings can form more meaningful aggregations. In the last section we investigate the QoE in virtual and augmented reality applications when these applications are implemented in mobile devices. Τhis part is concerned with more technical aspects such as mobility management, handoff strategies and resource allocation algorithms and their impact on users’ experience

    HbbTV-compliant Platform for Hybrid Media Delivery and Synchronization on Single- and Multi-Device Scenarios

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    [EN] The combination of broadcast and broadband (hybrid) technologies for delivering TV related media contents can bring fascinating opportunities. It is motivated by the large amount and diversity of media contents, together with the ubiquity and multiple connectivity capabilities of modern consumption devices. This paper presents an end-to-end platform for the preparation, delivery, and synchronized consumption of related hybrid (broadcast/broadband) media contents on a single device and/or on multiple close-by devices (i.e., a multi-device scenario). It is compatible with the latest version of the Hybrid Broadcast Broadband TV (HbbTV) standard (version 2.0.1). Additionally, it provides adaptive and efficient solutions for key issues not specified in that standard, but that are necessary to successfully deploy hybrid and multidevice media services. Moreover, apart from MPEG-DASH and HTML5, which are the broadband technologies adopted by HbbTV, the platform also provides support for using HTTP Live Streaming and Real-time Transport Protocol and its companion RTP Control Protocol broadband technologies. The presented platform can provide support for many hybrid media services. In this paper, in order to evaluate it, the use case of multi-device and multi-view TV service has been selected. The results of both objective and subjective assessments have been very satisfactory, in terms of performance (stability, smooth playout, delays, and sync accuracy), usability of the platform, usefulness of its functionalities, and the awaken interest in these kinds of platforms.This work was supported in part by the "Fondo Europeo de Desarrollo Regional" and in part by the Spanish Ministry of Economy and Competitiveness through R&D&I Support Program under Grant TEC2013-45492-R.Boronat, F.; Marfil-Reguero, D.; Montagud, M.; Pastor Castillo, FJ. (2017). HbbTV-compliant Platform for Hybrid Media Delivery and Synchronization on Single- and Multi-Device Scenarios. IEEE Transactions on Broadcasting. 1-26. https://doi.org/10.1109/TBC.2017.2781124S12

    Feasibility of ActivABLES to promote home-based exercise and physical activity of community-dwelling stroke survivors with support from caregivers : A mixed methods study

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    BackgroundTechnical applications can promote home-based exercise and physical activity of community-dwelling stroke survivors. Caregivers are often able and willing to assist with home-based exercise and physical activity but lack the knowledge and resources to do so. ActivABLES was established to promote home-based exercise and physical activity among community-dwelling stroke survivors, with support from their caregivers. The aim of our study is to investigate the feasibility of ActivABLES in terms of acceptability, demand, implementation and practicality.MethodsA convergent design of mixed methods research in which quantitative results were combined with personal experiences of a four-week use of ActivABLES by community-dwelling stroke survivors with support from their caregivers. Data collection before, during and after the four-week period included the Berg Balance Scale (BBS), Activities-Specific Balance Confidence Scale (ABC), Timed-Up-and-Go (TUG) and Five Times Sit to Stand Test (5xSST) and data from motion detectors. Semi-structured interviews were conducted with stroke survivors and caregivers after the four-week period. Descriptive statistics were used for quantitative data. Qualitative data was analysed with direct content analysis. Themes were identified related to the domains of feasibility: acceptability, demand, implementation and practicality. Data was integrated by examining any (dis)congruence in the quantitative and qualitative findings.ResultsTen stroke survivors aged 55-79years participated with their informal caregivers. Functional improvements were shown in BBS (+2.5), ABC (+0.9), TUG (-4.2) and 5xSST (-2.7). More physical activity was detected with motion detectors (stand up/sit down +2, number of steps +227, standing +0.3h, hours sitting/lying -0.3h). The qualitative interviews identified themes for each feasibility domain: (i) acceptability: appreciation, functional improvements, self-initiated activities and expressed potential for future stroke survivors; (2) demand: reported use, interest in further use and need for follow-up; (3) implementation: importance of feedback, variety of exercises and progression of exercises and (4) practicality: need for support and technical problems. The quantitative and qualitative findings converged well with each other and supported the feasibility of ActivABLES.ConclusionsActivABLES is feasible and can be a good asset for stroke survivors with slight or moderate disability to use in their homes. Further studies are needed with larger samples.Peer reviewe

    MediaSync: Handbook on Multimedia Synchronization

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    This book provides an approachable overview of the most recent advances in the fascinating field of media synchronization (mediasync), gathering contributions from the most representative and influential experts. Understanding the challenges of this field in the current multi-sensory, multi-device, and multi-protocol world is not an easy task. The book revisits the foundations of mediasync, including theoretical frameworks and models, highlights ongoing research efforts, like hybrid broadband broadcast (HBB) delivery and users' perception modeling (i.e., Quality of Experience or QoE), and paves the way for the future (e.g., towards the deployment of multi-sensory and ultra-realistic experiences). Although many advances around mediasync have been devised and deployed, this area of research is getting renewed attention to overcome remaining challenges in the next-generation (heterogeneous and ubiquitous) media ecosystem. Given the significant advances in this research area, its current relevance and the multiple disciplines it involves, the availability of a reference book on mediasync becomes necessary. This book fills the gap in this context. In particular, it addresses key aspects and reviews the most relevant contributions within the mediasync research space, from different perspectives. Mediasync: Handbook on Multimedia Synchronization is the perfect companion for scholars and practitioners that want to acquire strong knowledge about this research area, and also approach the challenges behind ensuring the best mediated experiences, by providing the adequate synchronization between the media elements that constitute these experiences
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