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When dealing with networks, performance management through conventional quality of service (QoS)-based methods becomes difficult and is often ineffective. In fact, quality emerges as an end-to-end factor, for it is particularly sensitive to the end-user perception of the overall service, i.e., the user’s quality of experience (QoE). However, the two are not independent from each other and their relationship has to be studied through metrics that go beyond the typical network parameters. To better explore the value of assessing QoE alongside QoS in high-speed, lossy networks, this paper presents an experimental methodology to understand the relation between network QoS onto service QoE, with the aim to perform a combined network-service assessment. Using video streaming services as the test-case (given their extended usage nowadays), in this paper, we provide studies on three network-impaired video-sets with the aim to provide a comprehensive evaluation of the effects of networks on video quality. First, the ReTRIeVED video set provides the means to understand the most impairing effects on networks. Furthermore, it triggered the idea to create our own sets, specialized in the most impairing conditions for 2-D and 3-D: the LIMP Video Quality Database and the 3-D-HEVC-Net Video Quality Database. Our study and methodology are meant to provide service providers with the means to pinpoint the working boundaries of their video-sets in face of different network conditions. At the same time, network operators may use our findings to predict how network control policies affect the user’s perception of the service. [ABSTRACT FROM AUTHOR]

A reconfigurable robotic gripper based on pneumatic technology has been designed and developed for grasping fabric materials in garment industries automation. The design is based on reconfigurable multidegree of freedom, which can manipulate single and multiple panels of limp materials. The design consist of four arms initially in a cross bar configuration, hosting four suction cups mounted on each of the arms. The design assures low inertia, high modularity and full flexibility adapting to the picking of limp materials in garment and shoe industries. The simulation referring to a worst-case operative cycle has been performed in the environment of a current industrial layout. The kinematic and dynamic performance of the gripper system is analyzed in ADAMS simulation software and the results are presented. The architecture of the gripper is simple and the choice of pneumatic actuators improves the reliability of the system. [ABSTRACT FROM AUTHOR]