QoE-centric service delivery: A collaborative approach among OTTs and ISPs

The provisioning of the quality to end users is a major objective for the successful deployment of multimedia services over the Internet. It is more and more evident from past research and service deployments that such an objective often requires a collaboration among the different parties that are involved in the delivery of the service. This paper specifically focuses on the cooperation between the Over-The-Top (OTTs) and the Internet Service Providers (ISPs) and proposes a novel service delivery approach that is purely driven by the Quality of Experience (QoE) provided to the final common users. Initially, we identify the need of the collaboration among the OTTs and the ISPs where we not only highlight some of the enterprise level motivations (revenue generation) but also the technical aspects which require collaboration. Later, we provide a reference architecture with the required modules and vertical interfaces for the interaction among the OTTs and the ISPs. Then, we provide a collaboration model where we focus on the modeling of the revenue, whose maximization drives the collaboration. The revenue is considered to be dependent on the user churn, which in turn is affected by the QoE and is modeled using the Sigmoid function. We illustrate simulation results based on our proposed collaboration approach which highlight how the proposed strategy increases the revenue generation and QoE for the OTTs and the ISPs hence providing a ground for ISP to join the loop of revenue generation between OTTs and users

Failure to achieve lupus low disease activity state (LLDAS) six months after diagnosis is associated with early damage accrual in Caucasian patients with systemic lupus erythematosus

Background: The aim was to assess the attainability and outcome of the lupus low disease activity state (LLDAS) in the early stages of systemic lupus erythematosus (SLE). Methods: LLDAS prevalence was evaluated at 6 (T1) and 18 (T2) months after diagnosis and treatment initiation (T0) in a monocentric cohort of 107 (median disease duration 9.7 months) prospectively followed Caucasian patients with SLE. Reasons for failure to achieve LLDAS were also investigated. Multivariate models were built to identify factors associated with lack of LLDAS achievement and to investigate the relationship between LLDAS and Systemic Lupus International Collaboration Clinics (SLICC)/Damage Index (SDI) accrual. Results: There were 47 (43.9%) patients in LLDAS at T1 and 48 (44.9%) at T2. The most frequent unmet LLDAS criterion was prednisolone dose >7.5 mg/day (83% of patients with no LLDAS at T1). Disease manifestations with the lowest remission rate during follow up were increased anti-double-stranded DNA (persistently present in 85.7% and 67.5% of cases at T1 and T2, respectively), low serum complement fractions (73.2% and 66.3%) and renal abnormalities (46.4% and 28.6%). Renal involvement at T0 was significantly associated with failure to achieve LLDAS both at T1 (OR 7.8, 95% CI 1.4-43.4; p = 0.019) and T2 (OR 3.9, 95% CI 1.4-10.6; p = 0.008). Presence of any organ damage (SDI â ¥1) at T2 was significantly associated with lack of LLDAS at T1 (OR 5.0, 95% CI 1.5-16.6; p = 0.009) and older age at diagnosis (OR 1.05 per year, 95% CI 1.01-1.09; p = 0.020). Conclusion: LLDAS is a promising treatment target in the early stages of SLE, being attainable and negatively associated with damage accrual, but it fit poorly to patients with renal involvement

Smart home energy management including renewable sources: A QoE-driven Approach

Smart Home Energy Management (SHEM) systems can introduce adjustments in the working period and operations of the home appliances to allow for energy cost savings, which can however affect the Quality of Experience (QoE) perceived by the user. This paper analyses this issue and proposes a QoE-aware SHEM system, which relies on the knowledge of the annoyance suffered by the users when the operations of appliances are changed with respect to the ideal user's preferences. Accordingly, a number of profiles which describe different usages are created in the design phase. At the deployment stage, users behavior and annoyance are registered to assign one of these profiles per appliance. The assigned profile is then exploited by the QoE-aware Cost Saving Appliance Scheduling and the QoEaware Renewable Source Power Allocation algorithms. The former is aimed at scheduling controlled loads based on users profile preferences and electricity prices making use of a greedy approach. The latter re-allocates appliances' operations whenever a surplus of energy has been made available by renewable energy sources. Experimental results demonstrate that the annoyance perceived by the users is severely diminished with respect to a QoE-unaware strategy, at the expenses of only a limited reduction in energy saving

A Procedure for rabbit blood serial collection

Blood serial collection is required for many applied reproduction and nutrition trials with rabbits. The experimental design of these researches very often includes repeated samplings of large volumes of blood for metabolites and hormones analysis. Our proposed procedure has been tested in many surveys with success. It is based on a blood collection by aspiration, featuring a sterile butterfly cannula with a vacuum tube. By this procedure, the use of syringes is avoided. As a matter of fact when a syringe is used, excessive suction frequently causes the rabbit blood vessel collapse. Furthermore a rough handling of blood, such as excessive suction or the forcing of clotted blood from a syringe, will cause hemolysis: this can interfere with the serum or plasma fractions needed. Blood collection from ear vessels is a technique commonly used with rabbits. The central ear artery is recommended for collecting larger volumes of blood (over 5ml). 10ml of blood/kg body weight can be collected in this manner but the rabbit must be carefully restrained and hematomas must be prevented by direct pressure. Removal of more than 10% of blood volume may result in hypovolemic shock, a potentially fatal reaction. Materials. For local anesthesia EMLA Cream (Lidocaine 2.5% + Prilocaine 2.5%) is a topically applied local anesthetic that is very useful in removing sensation from the venipuncture site. Blood collection set: 1) Butterfly cannula (23 gauge needle for small blood samples and 21 gauge for large samples). 2) Vacutainer blood collection tube and vacutainer holder. 3) Luer adapter (which is designed to allow the attachment of the butterfly to holders using a single venipuncture). Procedure. a) Remove the rabbit from its cage. Proper technique in grabbing and carrying a rabbit is important to prevent vertebral fractures. Grab the rabbit's skin in the shoulder region and place its head underneath your arm. Support the rabbit's legs with the hand of the arm that the head is tucked under. Alternatively, grab the rabbit's skin with both hands (over both the shoulder and the rump region). b) Apply about one thumb size of anesthetic cream on the site selected for blood collection, and leave the cream in contact with skin for 5 minutes c) Check the ear artery if visible and if doesn't dilate, tapping it gently (or flicking it) may help. For vessels dilation the use of topical irritants such as xylene is not recommended. Xylene tends to cause leukocytosis and if it comes in contact with blood, will cause hemolysis. Adequate dilation of vessels can generally be achieved by use of a heat lamp, alcohol or gentle massaging of the ear. d) Only when the blood vessel is clearly visible, with the needle bevel up, parallel to, and alongside the artery, insert the needle quickly under the skin and then into the artery. The needle has to be pointed towards the base of the ear and the insertion into the skin and artery can be performed in one complete motion. e) If the blood vessel has been correctly entered, blood will flow into the tubing of the butterfly cannula. f) Push the vacutainer tube all the way into the holder; vacuum is broken, and blood flows freely being drawn from the artery into the tube. g) Once the blood sample has been taken, the needle must be carefully and quickly removed. When the desired amount is collected, gently hold gauze over needle entry point and remove the needle. h) Hemostasis should be achieved applying pressure to the injected area using thumb and a piece of cotton. Keep pressure on the area for 60-90 seconds, or until blood stops flowing. i) Observe the rabbit for at least another 30 seconds to insure that bleeding has stopped. l) Return rabbit to cage, and check again in 10-15 minutes

Design of a High-Speed Ferrite-based Brushless DC Machine for Electric Vehicles

In the present paper an analytic procedure for the preliminary design of a High-Speed ferrite-based Brushless DC Machine (HS-BLDC) has been proposed. In particular, mechanical and electromagnetic modeling have been developed in order to take into account their mutual influence in the definition of the geometry of the electrical machine. In addition, suitable design targets have been imposed in accordance with electric vehicle application requirements. Hence, several mechanical and electromagnetic constraints have been introduced in order to comply with high-speed operation, preventing demagnetization issues of ferrite magnets as well. Subsequently, an HS-BLDC characterized by an inner rotor configuration has been designed in accordance with the proposed methodology. The analytical procedure and the corresponding results have been reported and validated by means of Finite Element Analyses (FEAs), highlighting the effectiveness of the proposed configuration and design solutions

Stereoselectivity and electrostatics in charge-transfer Mn- and Cs-TCNQ4 networks on Ag(100)

Controlling supramolecular self-assembly is a fundamental step towards molecular nanofabrication, which involves a formidable reverse engineering problem. It is known that a variety of structures are efficiently obtained by assembling appropriate organic molecules and transition metal atoms on well-defined substrates. Here we show that alkali atoms bring in new functionalities compared with transition metal atoms because of the interplay of local chemical bonding and long-range forces. Using atomic-resolution microscopy and theoretical modelling, we investigate the assembly of alkali (Cs) and transition metals (Mn) co-adsorbed with 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules, forming chiral superstructures on Ag(100). Whereas Mn-TCNQ4 domains are achiral, Cs-TCNQ4 forms chiral islands. The specific behaviour is traced back to the different nature of the Cs- and Mn-TCNQ bonding, opening a novel route for the chiral design of supramolecular architectures. Moreover, alkali atoms provide a means to modify the adlayer electrostatic properties, which is important for the design of metal–organic interfaces

No-Reference Objective Quality Metrics for 3D Point Clouds: A Review

Three-dimensional (3D) applications lead the digital transition toward more immersive and interactive multimedia technologies. Point clouds (PCs) are a fundamental element in capturing and rendering 3D digital environments, but they present significant challenges due to the large amount of data typically needed to represent them. Although PC compression techniques can reduce the size of PCs, they introduce degradations that can negatively impact the PC’s quality and therefore the object representation’s accuracy. This trade-off between data size and PC quality highlights the critical importance of PC quality assessment (PCQA) techniques. In this article, we review the state-of-the-art no-reference (NR) objective quality metrics for PCs, which can accurately estimate the quality of generated and compressed PCs solely based on feature information extracted from the distorted PC. These characteristics make NR PCQA metrics particularly suitable in real-world application scenarios where the original PC data are unavailable for comparison, such as in streaming applications

Controlling Media Player with Hands: A Transformer Approach and a Quality of Experience Assessment

In this article, we propose a Hand Gesture Recognition (HGR) system based on a novel deep transformer (DT) neural network for media player control. The extracted hand skeleton features are processed by separate transformers for each finger in isolation to better identify the finger characteristics to drive the following classification. The achieved HGR accuracy (0.853) outperforms state-of-the-art HGR approaches when tested on the popular NVIDIA dataset. Moreover, we conducted a subjective assessment involving 30 people to evaluate the Quality of Experience (QoE) provided by the proposed DT-HGR for controlling a media player application compared with two traditional input devices, i.e., mouse and keyboard. The assessment participants were asked to evaluate objective (accuracy) and subjective (physical fatigue, usability, pragmatic quality, and hedonic quality) measurements. We found that (i) the accuracy of DT-HGR is very high (91.67%), only slightly lower than that of traditional alternative interaction modalities; and that (ii) the perceived quality for DT-HGR in terms of satisfaction, comfort, and interactivity is very high, with an average Mean Opinion Score (MOS) value as high as 4.4, whereas the alternative approaches did not reach 3.8, which encourages a more pervasive adoption of the natural gesture interaction

Evaluation of Data Augmentation Techniques for Facial Expression Recognition Systems

Most Facial Expression Recognition (FER) systems rely on machine learning approaches that require large databases for an effective training. As these are not easily available, a good solution is to augment the databases with appropriate data augmentation (DA) techniques, which are typically based on either geometric transformation or oversampling augmentations (e.g., generative adversarial networks (GANs)). However, it is not always easy to understand which DA technique may be more convenient for FER systems because most state-of-the-art experiments use different settings which makes the impact of DA techniques not comparable. To advance in this respect, in this paper, we evaluate and compare the impact of using well-established DA techniques on the emotion recognition accuracy of a FER system based on the well-known VGG16 convolutional neural network (CNN). In particular, we consider both geometric transformations and GAN to increase the amount of training images. We performed cross-database evaluations: training with the "augmented" KDEF database and testing with two different databases (CK+ and ExpW). The best results were obtained combining horizontal reflection, translation and GAN, bringing an accuracy increase of approximately 30%. This outperforms alternative approaches, except for the one technique that could however rely on a quite bigger database

Ensaios avançados com fibras ópticas = advanced characterization of optical fibers

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia de Electrónica e TelecomunicaçõesAs fibras ópticas estão omnipresentes na camada física das modernas redes de comunicação, desde as transmissões de longo alcance até ao acesso residencial. Para fazer frente ao contínuo aumento das necessidades de largura de banda, o aumento das velocidades de transmissão comprime as margens dos sistemas. Neste cenário, a caracterização das ligações ópticas requer métodos de medida avançados de forma a avaliar devidamente o desempenho do sistema, a capacidade da rede em suportar a aplicação actual ou uma futura actualização de serviços. Neste trabalho, fazemos uma revisão dos métodos e das tecnologias adoptadas para a medição do perfil de atenuação espectral, da dispersão cromática e da dispersão dos modos de polarização. Apresentamos os resultados de medidas avançadas em fibras ópticas monomodo em ambiente de laboratório e em ligações utilizadas nocampo. Recorrendo a um avançado equipamento comercial, verificamos o perfil de atenuação espectral em cabos ópticos instalados no campo; de acordo com o método do desvio de fase (phase shift) medimos a dispersão cromática e, através da técnica do analisador fixo (fixed analyzer), avaliamos a dispersão dos modos de polarização. Reportamos e analisamos os dados recolhidos em cabos ópticos instalados no campo, discutindo em detalhe os resultados referentes à dispersão dos modos de polarização, cuja distribuição de valores se desvia significativamente da esperada distribuição de Maxwell. Apresentamos o modelo de “PMD hinge”, e concluímos que este modelo fornece uma justificação plausível a quanto foi observado.Abstract: Optical fibers are ubiquitous in the physical layer of modern communication networks, from ultra-long haul transmission to residential access. To cope with the growing bandwidth demand, data rates increase is placing pressure on systems margins. In this scenario, the characterization of optical links calls for advanced measurement methods, in order to properly evaluate overall system performance, capabilities of the network for the current application and for future services upgrades. In this thesis, we review the methods and technologies adopted for the measurement of spectral attenuation profiles, chromatic dispersion and polarization mode dispersion. We present results of advanced measurements on single mode optical fibers under laboratory conditions, and fiber links employed under field conditions. For the characterization task, we operate state of the art commercial equipment, implementing the phase shift method for chromatic dispersion measurements, and the fixed analyzer technique for the polarization mode dispersion measurements. We report and analyse the data collected in deployed optical cables discussing in detail the polarization mode dispersion results, which deviate substantially from the expected maxwellian distribution. We present the so-called “PMD hinge” model, and conclude that this model gives a plausible justification of the observations