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The recent growth in both number of high specification mobile devices and network multimedia data demand, has made difficult supporting access to the multimedia content at high user Quality of Experience (QoE) levels. It is even m...
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The recent growth in both number of high specification mobile devices and network multimedia data demand, has made difficult supporting access to the multimedia content at high user Quality of Experience (QoE) levels. It is even more challenging to support offering such services adjusted to user specific requirements in current heterogeneous wireless network environments (HWNE). This paper proposes a novel Prioritized Adaptive Real-time Multi-user Access Network Selection framework (P-ARMANS) which employs a Markov Decision Process (MDP) solution to perform improved bandwidth resource allocation. P-ARMANS enables load balancing during multimedia delivery when users with diverse priority and different device screen resolutions access various services. Modeling and simulations show how P-ARMANS distributes content with different types of traffic and load among typical and business users at higher QoE levels compared to a classic no-priority approach.
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The demand of media delivery services has increased with the popularity of social media and with the evolution of the user's devices (i.e., smartphones, laptops, and tablets) pushing towards new contents distribution models. The c...
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The demand of media delivery services has increased with the popularity of social media and with the evolution of the user's devices (i.e., smartphones, laptops, and tablets) pushing towards new contents distribution models. The coexistence of go-live and on-demand media content requires a combined broadcast/unicast delivery model with the efficient management of the wireless access as a key issue. A twofold target needs to be reached: optimizing the load balance among coexisting networks and offering adequate quality of service (QoS) to users. To achieve this target for mobile video service delivery over heterogeneous networks (HetNet) scenarios, this paper proposes a solution based on an additive logarithmic weighting (ALOW) algorithm combining received signal power, network load, packet delay, user's equipment, and user's credit budget. ALOW is optimized by means of a cooperative game theory (GATH) approach. The proposed solution, named ALOWGATH (i.e., ALOW + GATH), has been tested on realistic HetNet scenarios and compared to the state of the art of the network selection and balancing algorithms. Results show an improved performance in terms of throughput, satisfaction index and overall video quality delivered, with reduced computational complexity.
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Coast erosion is a process that degrades a coastal profile and is mainly due to natural factors (e.g., related to climate change) and overcrowding (e.g., urbanization and massive tourism). While the first cause can be considered a...
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Coast erosion is a process that degrades a coastal profile and is mainly due to natural factors (e.g., related to climate change) and overcrowding (e.g., urbanization and massive tourism). While the first cause can be considered as a slow process, the growing presence of humans is leading to rapid aging of coasts. The Mediterranean Sea authorities are focusing on the necessity for a systematic and comprehensive approach to the management of littoral areas. In this context, Italy is searching for a promising solution to safeguard coasts but, at the same time, to manage in an intelligent and "green" way the big amount of tourists. Research communities all over the world indicated the Internet of Things (IoT) as a valid technology to develop solutions in order to try solving or mitigating the coastal erosion problem. IoT-based techniques allow to manage heterogeneous and massive data for real-time monitoring and decision making and can be used for coastal environment and crowd level monitoring. This article presents a monitoring system based on the Social IoT (SIoT), a new paradigm that defines a network where every node is an object capable of establishing the social relationships with other things in an autonomous way according to specific rules. Thanks to social relationships, all involved devices in the monitoring system (i.e., sensors, cameras, and smartphones) are able to collect and exchange information. The proposed system, developed and installed in Cagliari (Italy), is able to evaluate the occupational state of a beach considering environmental and crowding data collected by devices and feedback sent by users.
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Hybrid broadcast broadband TV (HbbTV) is a standardization initiative aimed at harmonising the broadcast and broadband delivery of entertainment services to consumers through connected TVs, set-top boxes, and multiscreen devices. ...
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Hybrid broadcast broadband TV (HbbTV) is a standardization initiative aimed at harmonising the broadcast and broadband delivery of entertainment services to consumers through connected TVs, set-top boxes, and multiscreen devices. A smart home (SH) is a suitable home setup where appliances and devices can be automatically controlled remotely from any Internet-connected device. For the seamless integration of a variety of devices within the SH, HbbTV solutions are gaining a pivotal role, acting as a central hub for audio and video broadcasting services, home automation and other devices, including smartphones, tablets and Internet of Things (IoT)-enabled devices. In this context, a standard, compliant and platform independent, solution is preferred as it can enable dynamic environment where heterogeneous devices contribute to the overall user experience. This paper proposes an architecture for the seamless integration of a SH environment with a HbbTV-enabled television set and consumer's handled devices, such as smartphones and tablets, using the HbbTV 2.0.1 Companions Screen and Multimedia Synchronization framework. A complete architectural design and its hardware implementation have been developed and deployed as a proof of concept. Subjective tests based on mean opinion score (MOS) have been conducted to assess the benefits of the proposed system in terms of Quality of Experience (QoE). Results are encouraging and show that the accurate design of hybrid services through HbbTV could lead to satisfactory QoE perceived by users in the fruition of unified TV and SH services. Based on the obtained results, a preferred common configuration of notifications in terms of position, duration, and sound was indicated.
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In DVB-T/T2 broadcasting single frequency network (SFN) multipath interference (MPI) at the receiver antenna is a critical issue. The capability to elaborate those signals depends on both synchronization strategy used and coded or...
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In DVB-T/T2 broadcasting single frequency network (SFN) multipath interference (MPI) at the receiver antenna is a critical issue. The capability to elaborate those signals depends on both synchronization strategy used and coded orthogonal frequency-division multiplexing (COFDM) modulation properties. An efficient COFDM system requires the guard interval as short as possible and such as to protect the system from the MPI. To cope with this problem a static delay adjustment obtained by fitting the launching time of each broadcast station is introduced so that the time difference of the incoming signals within the reception area falls into the COFDM guard interval. This work investigates the use of advanced simulated annealing to optimize transmission parameters such as the static delay, gain and orientation of sector antennas of DVB-T/T2 transmitters in SFNs. In particular, we identify the static delay adjustment map to maximize the coverage area according to quality of service requirements. The proposed approach has been validated for DVB-T/T2 network planning in the Basque Country (Spain) and Sardinia island (Italy). Different density of transmitters, generalized geography of territory are considered for the best setting of the parameters involved. Reliability studies are included to demonstrate the efficacy of the method.
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