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The introduction of small Unmanned Aircraft Systems (sUAS) in an increasingly wide range of civil applications implies several challenges for the integration of manned and unmanned traffic in the controlled and uncontrolled low-level airspace, both at a technological and procedural level. This paper discusses the design of an integrated platform for the management of contingency events and the improvement of situation awareness of the pilot. To this end, a head-up display, based on augmented reality (AR) technology, is designed to provide the pilot with visual cues that should improve his awareness of admissible flight volumes. A force feedback is also provided by a haptic joystick, which suggests manoeuvres to avoid collisions or violation of airspace constraints. Tests in an actual airport facility are expected to be conducted in 2021. In the meantime, a possible realistic scenario is analysed, illustrating the interactions among the various actors and components of the system.

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality in the world, and leads to a substantial burden on healthcare services. Effective and timely management of patients with COPD has been essential to alleviate COPD exacerbation, improve the quality of life, and consequently reduce the economic burden. To achieve this, we propose an innovative tele-medicine system based on Smart Breath Analyzer (SBA) device and devoted to the tele-monitoring of exhaled air in patients suffering chronic respiratory failure and home-assisted by mechanical ventilation. In this work the main characteristics of the developed tele-medicine system are presented together with preliminary pre-clinical test results. The preliminary tests demonstrated the effective possibility to enter the SBAs in medical practice in home-ventilo-therapy protocols by suitable interpretation of the monitored parameters from a physiological point of view. Thanks to a network composed by many SBA devices that send patients data to a remote server, the doctor can tele-monitor the status of patient in order to check any state of exacerbation of the disease and consequently improve quality of life in COPD.

Peer-to-peer streaming is a well-known technology for the large-scale distribution of real-time audio/video contents. Delay requirements are very strict in interactive real-time scenarios (such as synchronous distance learning), where playback lag should be of the order of seconds. Playback continuity is another key aspect in these cases: in presence of peer churning and network congestion, a peer-to-peer overlay should quickly rearrange connections among receiving nodes to avoid freezing phenomena that may compromise audio/video understanding. For this reason, we designed a QoS monitoring algorithm that quickly detects broken or congested links: each receiving node is able to independently decide whether it should switch to a secondary sending node, called “fallback node”. The architecture takes advantage of a multithreaded design based on lock-free data structures, which improve the performance by avoiding synchronization among threads. We will show the good responsiveness of the proposed approach on machines with different computational capabilities: measured times prove both departures of nodes and QoS degradations are promptly detected and clients can quickly restore a stream reception. According to PSNR and SSIM, two well-known full-reference video quality metrics, QoE remains acceptable on receiving nodes of our resilient overlay also in presence of swap procedures.

Motor impairments affecting old people require a regular and reliable monitoring of the body functional autonomy. Low cost camera-based systems, initially designed for entertainment applications, have been evaluated for a possible adoption in diagnosis and rehabilitation. Unfortunately, their adoption is partially hampered by noise, precision and accuracy issues. In this paper we evaluate the performance of the Kinect One sensor in assessing the shoulder joint mobility in subjects with different body sizes: we measure the maximum angle reached by a patient raising his/her arms, the time needed to perform such action and the time the patient is able to keep his/her arms up. The preliminary tests conducted on two healthy subjects revealed no significant difference in terms of relative error among measures collected for subjects with different body heights and sizes. However, statistical tests suggested a correlation between the relative errors on large angle amplitudes and the time spent with arms up.

The use of UAVs has recently been proposed for services in civil airports and other sensitive areas. Besides specific regulations from authorities, the situation awareness of the UAV operator is a key aspect for a safe coexistence between manned and unmanned traffic. The operator must be provided in real-time with contextually relevant information, in order to take the proper actions promptly based on the notified contingency. Augmented reality can be adopted to superimpose such additional information on the real-world scene. After the definition of an architecture for the integration of drone operations in the airspace, in this paper the interface and the layout of an augmented reality application for the situation awareness of the pilot are designed and discussed.

Among the techniques for digitalization and 3D modeling of real objects, photogrammetry is assuming an increasing importance due to easy procedures and low costs of hardware and software equipment. Thanks to the advances of the last years in computer vision, photogrammetry software can reconstruct the geometric 3D shape of an object from a series of pictures taken from different viewpoints. In particular, close-range photogrammetry for the reconstruction of small objects allows performing image acquisition around the target object almost automatically. In this paper we present a brief survey of the hardware setup, algorithms and software tools for photogrammetric acquisition and reconstruction applied to small objects, aimed at achieving a good photorealism level without an excessive computational load.

Gesture-based touchless devices are becoming a widespread alternative to traditional gaming devices such as joysticks or gamepads. However, the impact of such devices on the user experience has to be evaluated, especially if we consider that most users are more familiar with classical handheld gaming controllers. In virtual reality applications, they influence not only the traditional usability, but also the user perception related to some peculiarities of immersive environments. In this paper, we evaluate both these aspects by comparing the user experience with the Myo armband touchless interface and the Vive controller distributed with the HTC Vive headset. We focused on a virtual navigator we developed for HTC Vive to allow users exploring the organs of the human body and navigating inside them. We recruited 78 subjects to test the virtual environment and asked them to fill in a questionnaire: we combined two generic purpose questionnaires focusing on the system usability (UMUX and SUS) and a presence questionnaire, which was specifically designed for virtual environments. We conducted a statistical analysis to study the effects of a touchless interaction on the user experience. The results revealed a better usability of the Vive controller, even though the effort to learn how to use the two devices is similar. In particular, difficulties in using Myo have a significant impact on immersion and adaptation in the virtual environment.

Natural user interfaces have been widely adopted in several application fields. In particular, they are employed in learning environments to increase the motivation and the engagement of students.

Within the BRAVO project, we are designing four virtual characters that will interact with children affected by ADHD. In order to assess the quality of the designed characters, we propose a metric to subjectively evaluate the level of intelligibility of the character’s facial expression. The results of a preliminary user study conducted with 23 individuals show that our quality measure can be used to quickly identify flawed expressions and iteratively improve the design of the characters.

Minimally invasive techniques, such as laparoscopy and radiofrequency ablation of tumors, bring important advantages in surgery: by minimizing incisions on the patient's body, they can reduce the hospitalization period and the risk of postoperative complications. Unfortunately, they come with drawbacks for surgeons, who have a restricted vision of the operation area through an indirect access and 2D images provided by a camera inserted in the body. Augmented reality provides an "X-ray vision" of the patient anatomy thanks to the visualization of the internal organs of the patient. In this way, surgeons are free from the task of mentally associating the content from CT images to the operative scene. We present a navigation system that supports surgeons in preoperative and intraoperative phases and an augmented reality system that superimposes virtual organs on the patient's body together with depth and distance information. We implemented a combination of visual and audio cues allowing the surgeon to improve the intervention precision and avoid the risk of damaging anatomical structures. The test scenarios proved the good efficacy and accuracy of the system. Moreover, tests in the operating room suggested some modifications to the tracking system to make it more robust with respect to occlusions. Graphical Abstract Augmented visualization in minimally invasive surgery.

Nowadays grid portals are characterized by various and different features and are implemented in very differing programming languages and technologies, still having many structural aspects in common. This paper describes a RESTful Web API, named GRB_WAPI, specifically developed for grid computing that encapsulates all grid control and computation logic need to build a grid portal. Through the adoption of this API a portal developer does not have to deal with grid technical details focusing just on the high level design of her system and on some other aspects that concern presentation, such as portal usability and functionality. The idea of developing a traditional library has been discarded in order to free portal developers from a particular implementation technology. Thanks to this choice the portal presentation logic can be implemented in any web technology and can be deployed on a different server. Traditional Web Services and SOAP protocol approach has been discarded in order to adopt a RESTful approach to make the Web APIs lighter and also to take advantage of some other aspects illustrated in the paper.

The diffusion of small low cost sensors has opened new opportunities for the design of real-time monitoring systems in several application fields. Internet of Things (IoT) is a new branch of Information Technology that connects several of these heterogeneous devices through different network protocols to provide large scale interoperability. In this paper we describe how some open source software tools can be integrated to collect, monitor and process streams of data received in real-time by sensor devices. The tools we have employed are the Things-Board platform to collect sensor data and the Spark Streaming framework for cluster computing to perform data analytics. The presented architecture can be exploited in various monitoring scenarios (such as clinical, environmental or energetic processes) to study the trend of some key parameters and also to produce alerts in case of problematic situations. Without loss of generality, we focus on biomedical data about the breath of patients affected by chronic respiratory disease: real-time monitoring of breath parameters enables automatic ventilotherapy and allows also to warn doctors in time in severe cases.

Augmented reality plays an important role in cultural heritage and education. The magic effect of 3D animated objects can enhance students’ interest, attention and engagement in school subjects. Moreover, augmented reality can help understand spatial concepts and the working principles of complex mechanical components. In such context, machines designed by Leonardo Da Vinci are a perfect case study for augmented reality technologies. This paper presents a mobile augmented reality application developed for an exhibit on Leonardo’s inventions: it shows the overall structure and the working principles of some machines recognized on the pages of the Atlantic Codex. We used Blender to design the animated 3D models of the machines and the ARToolkit and Vuforia frameworks to superimpose virtual models over Leonardo’s sketches framed by the camera of mobile devices. Subjective data about user experience collected through some questionnaires proved how AR applications can improve the dominant learning style in accordance with Kolb’s theory.

We analyzed PSNR, BIPSNR, SSIM, 3SSIM, MSSSIM, VQM for various packet loss fractions.A lower bitrate mitigates PSNR impairments caused by packet losses.BIPSNR has less probability than PSNR to be significantly influenced by packet losses.Among structural similarity metrics, SSIM is the least affected by packet losses.VQM metric is the most affected by packet losses. Video quality is a key factor in modern video streaming systems. Video compression artifacts affect it but also delay, jitter and packet loss may compromise it. Objective metrics have been proposed to emulate the human visual system: several experimental works have evaluated their adherence to opinions expressed by real users. Instead of dealing with subjective tests, we focused on the effects of network packet losses on objective metrics: since quality metrics are generally computationally intensive, a convenient approach could consist in inferring information about transmission quality from network impairment statistics. We did experimental tests on two computer-animated videos, whose high color contrasts allow a fair comparison between content dependent and content independent metrics. We studied the encoding parameters that minimize/maximize the values of some metrics (PSNR, BI-PSNR, SSIM, 3SSIM, MSSSIM, VQM) for several packet loss percentages. We analyzed also the Empirical Cumulative Density Function of the degradations of quality metrics.

In this paper we describe a grid problem solving environment we developed for financial applications. We based its development on a portlet framework we have specifically developed and on a set of Web APIs that encapsulate all grid control and computation logic. Even though nowadays grid portals are characterized by various and different features and are implemented in very differing programming languages and technologies, we thought that they have many structural aspects in common. For this reason we decided to design and implement a set of Grid specific Web APIs, that we called GRB WAPI. Through them, a portal developer will not have to deal with grid technical details and will be able to manage a high level design. A portal developer will be able to concentrate on some other aspects that concern presentation, such as portal usability and functionality. We discarded the idea of developing a traditional library in order to free portal developers from a particular implementation technology. Thanks to this choice the portal presentation logic can be implemented in any web technology and can be on a different server

The paper deals with the development of virtual surgical simulator for microanastomosis developed within the INTERREG (Italy-Greece) MICRO project. Microanastomosis is a surgical technique that involves, under optical magnification, the conjunction of blood vessels of a few millimeters diameter and is used also to support the surgical treatment of tumours. This manuscript describes the two principal solutions analysed during the progress of the MICRO project. The first step concerns the development of the simulator using the Unity3D engine; the second step describes an evolution of the surgical simulator to support remote control by a haptic interface via web using the WebGL platform based on JavaScript code. For both, a force feedback module has been implemented that reads data coming from the simulator and converts them to generate a servo control action on the haptic interface. For both solutions, some results of the implemented simulator are described .

Aim of this work was to study the perception of affordances in VR according to a cognitive neuroscience. In order to investigate this topic we focused our analysis on the perception of affordances during a game, the Leap Motion Controller (LM). The sample was composed of 10 university students matched by age and sex. The subjects performed in Thinking training and in Immersive Affordance Condition (a virtual training with LM and a Real training). After each training the subject had to perform a recognition task. During the task ERP components were measured through EEG. The results highlighted that, during the LM training, attentional components changed. In the occipital lobes, which is entrusted to visual sensory, we got increased latencies; on the contrary, in frontal lobe, where the brain mainly activates for attention and action planning, we got decreased latencies.

P2P streaming systems exploit the high scalability of P2P networks to propagate multimedia streams to wide areas in a distributed fashion. A P2P network is made up of several logic connections among peer nodes, which can form a mesh or a tree overlay. Interactive real-time streaming imposes very strict delay constraints: in e-learning environments, for instance, only a high level of synchrony with the live event may allow users to ask questions in real-time to the lecture speaker. Despite their resilience to peer churning, mesh overlays are affected by a high and variable delay, which hampers their adoption in interactive applications. Playback discontinuity, caused by missing chunks, may be a serious problem too, since it may compromise the speech understanding. On the contrary, multi-tree MDC-based overlays can guarantee a smooth playback continuity, since a stream can be fluently reproduced also when some descriptions are lost. The queuing and the elaboration delay of the nodes should be kept under control to reduce the overall end-to-end delay on each tree branch. In this work we describe a framework for the construction of reliable tree overlays: we designed a smooth switch-to-fallback mechanism to quickly replace nodes leaving the overlay, a channel for packet recovery and a very efficient engine that collects MDC descriptions coming from parent nodes. The experimental data we reported in the last section reveal a low CPU usage and a very low elaboration delay in collecting MDC descriptions.

 Abstract—In spite of massive research efforts devoted to the advance of the technologies for large-scale live distribution of audio-video IP streams, no totally satisfying solutions seem to have emerged so far. CDNs are still expensive and P2P-TV systems face substantial delay limitations. As the deployment of a global terrestrial IP multicast infrastructure still looks far, turning the attention to satellite-based multicast would seem a sensible choice. However, the cost of such technology has been a stumbling block until now. That is where the CHARMS architecture comes in. It is designed to take advantage of the formidable properties of the satellite without requiring a generic user to install any sort of satellite receiver or dish. Its cornerstone is the recursive terrestrial relaying of satellite streams a number of properly equipped hosts are able to receive. The present paper relates about the results of the OpenSatRelaying project, aimed at the implementation and testing of the CHARMS architecture.

—Peer-to-peer streaming is a well-known technology for the large-scale distribution of audio/video contents. Its widespread adoption derives from the possibility of having a good scalability without the need for the deployment of expensive infrastructures such as Content Delivery Networks (CDNs). We think real-time streaming of lessons could open new interesting opportunities in e-learning systems by encouraging interactivity between teachers and learners. Delay requirements are very strict in interactive e-learning scenarios, where playback lag between the event in the real world and the received audio/video should not exceed a few seconds. Only a very short delay would allow students to ask questions during the lesson. At the same time, playback continuity is a key aspect too, since holes in the stream reproduction could seriously compromise the understanding of lectures. In this paper we compared some solutions that try to overcome the limitations of traditional mesh-based P2P systems, which are usually affected by long and unpredictable delays. We finally tried to outline which of the analyzed solutions appears the most suitable one to meet e-learning requirements.

Native IP multicast would be the best solution to distribute live streaming contents among various destinations since the real-time nature of such applications usually imposes strict delay constraints. Application Layer Multicast (ALM) platforms are emerging as a solution to overcome the well- known lack of a globally supported native multicast. Since the development of ALM applications is slowed by complexity and portability issues, we designed an open source C library framework that takes care of RTP/RTCP technical details and fosters a modular and higher level design. Besides it frees ALM developers from spending time in porting operations from Unix to Windows operating systems.

In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user's hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects). After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP) components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning.