Managing video objects in large peer-to-peer systems

In peer-to-peer video systems, most hosts will retain only a small portion of a video after its playback. This presents two challenges in managing video data in such systems: (1) how a host can find enough video pieces, which may scatter among the whole system, to assemble a complete video, and (2) given a limited buffer size, what part of a video a host should cache. In this thesis, we address these problems with a new distributive file management technique. In our scheme, we organize hosts into many cells, each of which is a distinct set of hosts which together can supply a video in its entirety. Because each cell is dynamically created and individually managed as an independent video supplier, our technique addresses the two problems, video lookup and caching, simultaneously. First, a client looking for a video can stop its search as soon as it finds a host that caches any part of the video. This dramatically reduces the search scope of a video lookup. Second, caching operations can now be coordinated within each cell to balance data redundancy in the system. We have implemented a Gnutella-like simulation network and use it as a testbed to evaluate the proposed technique. Our extensive study shows convincingly the performance advantage of the new scheme

EXPLORING THE UTILIZATION OF WEBCAM VIDEOS TO ASSESS EXERCISE TRAINING AND FITNESS ASSESSMENT SKILLS OF STUDENTS IN AN ONLINE GRADUATE EXERCISE SCIENCE COURSE: A CASE STUDY

Online learning (web-based education) continues to have a significant impact on higher education. Increasingly, students seek fully online programs in a broad range of disciplines at the undergraduate and graduate levels. College faculty have produced increasingly more research focusing on how to teach online, including best practices and appropriate web-based course pedagogy. Faculty and college administrators regularly discuss what curricula is appropriate for online learning versus what curricula does not adapt well into online courses. This is especially true for course content in the psychomotor domain which is typically taught in live lab-based courses and traditional "hands-on" focused classroom presentations. A few of the significant challenges for instructors teaching psychomotor skills in the online course environment include: how to appropriately assess student learning of hands-on skills, how to confirm psychomotor skill acquisition, and how to verify the student can teach the skills to other individuals. This research provides a qualitative focus within a problem solving case study that introduces a possible solution for assessing fitness assessment and exercise training techniques learned in a web-based course. This paper presents background information on the use of web-based learning in the general sphere of higher education and outlines the current range of online education courses in fitness, exercise science, health, and wellness education. This inquiry focuses on a case study analysis exploring the utilization of webcam videos as new assessment tools implemented in a fully web-based course, PRF 711: An Integrated Approach to Fitness and Wellness, offered in an Exercise Science and Health Promotion Graduate Program at California University of Pennsylvania. The web-based graduate program offers several psychomotor skill based courses, recently developed at the University. The research results are analyzed supported by survey data, mining data from assessment documents, online classroom observation, and interviews of several students, the instructor, and three subject matter professionals. One goal of this study was to identify the entry-level technology skills, professional experience, client accessibility, and confidence with technology of students enrolled in the PRF 711 course. Another goal was to analyze the experiences and feedback of five students, who used webcams to submit online video/audio course assignments focused on "hands-on" content in the psychomotor domain, more specifically, fitness assessment and exercise activities. The five students were asked to describe experiences, suggestions, and questions regarding the processes and protocols used during video set-up, video recording, project submission, and instructor feedback. An additional goal was to analyze the experiences of the instructor who implemented the video project protocols, evaluated student video projects, and faux-graded student performance. The study also analyzed interview data collected from a variety of stakeholders who made observations and suggestions regarding the video assessment protocol, the assessment instruments, as well provided feedback at the end of the course regarding summative evaluation of the video assessment intervention. The stakeholders interviewed included the Director of Training and, the Director of Content Development for the National Academy of Sports Medicine (NASM), who were jointly responsible for designing much of the curriculum used in the PRF 711: An Integrated Approach to Fitness and Wellness course. Additionally, feedback and insight were analyzed from an instructional designer. Constant comparison of stakeholder feedback and analytic induction were used to organize and categorize the data. Study results show that the new webcam video assessment protocol is a viable solution for assessing hands-on skills in the PRF 711 online course. Several challenges, issues, and solutions are addressed. The study results will be used at California University of Pennsylvania to enhance assessment protocols using webcam videos in courses that require the learning of "hands-on" and psychomotor skills. The study results may also be used as a conceptual framework to examine how web-based courses in several disciplines, with a significant amount of psychomotor objectives, could include online video assessment techniques. The implications of this research for healthcare/fitness educators, students, college administrators, and instructional designers is reviewed in the discussion. Suggestions for areas of further research and future practice are included

Is Multimedia Multisensorial? - A Review of Mulsemedia Systems

© 2018 Copyright held by the owner/author(s). Mulsemedia - multiple sensorial media - makes possible the inclusion of layered sensory stimulation and interaction through multiple sensory channels. e recent upsurge in technology and wearables provides mulsemedia researchers a vehicle for potentially boundless choice. However, in order to build systems that integrate various senses, there are still some issues that need to be addressed. is review deals with mulsemedia topics remained insu ciently explored by previous work, with a focus on multi-multi (multiple media - multiple senses) perspective, where multiple types of media engage multiple senses. Moreover, it addresses the evolution of previously identi ed challenges in this area and formulates new exploration directions.This article was funded by the European Union’s Horizon 2020 Research and Innovation program under Grant Agreement no. 688503

Using Music to Modify Step-Rate and Running Biomechanics in Healthy Runners

Context: Running-related injury (RRI) is a significant public health issue that may be caused by injurious running biomechanics. Increasing step-rate (SR) using gait retraining may prevent and treat RRI. The Optimizing Performance Through Intrinsic Motivation and Attention for Learning (OPTIMAL) theory indicates enhanced expectancies, autonomy, and external focus of attention will optimize motor learning. Music has been shown to create enhanced expectancies, can provide incidental choices (autonomy), directs attention externally, and may increase compliance. No studies have investigated if music can be used to alter SR and running biomechanics or strategies that may improve compliance to gait retraining. Objective: The purpose of this study was to 1) compare differences in SR and running biomechanics between those who use music auditory cueing (MUS) and those who use metronome auditory cueing (MET) during the phases of a temporospatial gait retraining protocol, 2) compare differences in RPE change scores across four temporospatial gait retraining sessions between the MUS and MET group, and 3) determine if there is an association between groups (MUS and MET) and compliance to a self-administered, temporospatial gait retraining protocol and describe the likelihood of compliance between groups (MUS and MET). Methods: Thirty, healthy recreational runners were included and randomly placed in either the MET or MUS group. Inertial measurement unit motion analysis collected SR, peak positive tibial acceleration (PPA), and peak stance phase hip adduction (peakHIPADD) during the stance phase of running. A cellular device application collected running volume and SR data when participants ran outside of the lab, which defined compliance. The Borg’s rate of perceived exertion (RPE) scale was used to compare change in RPE between groups. A multivariate repeated measures ANOVA was used to compare SR, PPA, and peakHIPADD from the introductory pretest (INTROpre) and the three posttests (INTROpost, LABpost, SELFpost). Change scores between baseline RPE and RPE after each gait retraining session were calculated and analyzed using a mixed repeated measures ANOVA. SR and running volume were derived from the cellular application exports and compliance was defined as 1) maintaining an average SR within +/- two steps per minute of the target SR throughout each run and 2) maintaining the average running volume. Runners were assigned as “compliant” and “noncompliant”. A Fischer’s exact test was performed, and an odds ratio was calculated to determine association and likelihood of compliance between groups. Results: Both groups increased SR between the INTROpre and introductory posttest (INTROpost) (p \u3c.001), and the increase in SR was maintained at all other posttest timepoints (LABpost and SELFpost). There were no differences in PPA or peakHIPADD at any posttest timepoints regardless of group. No significant differences in RPE change scores between groups across time were found. There was a significant association between group and compliance (p = .05) and the MUS group was ~6 times as likely to comply with the self-administered gait retraining program. Conclusions: SR can be altered using either a metronome or music tempo. Both a metronome and music can be used as an auditory cue without creating increased perception of exertion. Runners using the music auditory cueing may continue to practice their new target SR more than runners assigned a metronome cueing, which provides rationale to use music to retrain SR within a self-administered gait retraining protocol. Running biomechanics may not have changed since SR was only increased by 5% so future research should repeat the current study methods using larger increases in SR

Bendit_I/O: A System for Extending Mediated and Networked Performance Techniques to Circuit-Bent Devices

Circuit bending—the act of modifying a consumer device\u27s internal circuitry in search of new, previously-unintended responses—provides artists with a chance to subvert expectations for how a certain piece of hardware should be utilized, asking them to view everyday objects as complex electronic instruments. Along with the ability to create avant-garde instruments from unique and nostalgic sound sources, the practice of circuit bending serves as a methodology for exploring the histories of discarded objects through activism, democratization, and creative resurrection. While a rich history of circuit bending continues to inspire artists today, the recent advent of smart musical instruments and the growing number of hybrid tools available for creating connective musical experiences through networks asks us to reconsider the ways in which repurposed devices can continue to play a role in modern sonic art. Bendit_I/O serves as a synthesis of the technologies and aesthetics of the circuit bending and Networked Musical Performance (NMP) practices. The framework extends techniques native to the practices of telematic and network art to hacked hardware so that artists can design collaborative and mediated experiences that incorporate old devices into new realities. Consisting of user-friendly hardware and software components, Bendit_I/O aims to be an entry point for novice artists into both of the creative realms it brings together. This document presents details on the components of the Bendit_I/O framework along with an analysis of their use in three new compositions. Additional research serves to place the framework in historical context through literature reviews of previous work undertaken in the circuit bending and networked musical performance practices. Additionally, a case is made for performing hacked consumer hardware across a wireless network, emphasizing how extensions to current circuit bending and NMP practices provide the ability to probe our relationships with hardware through collaborative, mediated, and multimodal methods

C-9 and Other Microgravity Simulations

This document represents a summary of medical and scientific evaluations conducted aboard the C-9 and other NASA-sponsored aircraft from June 2008 to June 2009. Included is a general overview of investigations manifested and coordinated by the Human Adaptation and Counter-measures Division. A collection of brief reports that describe tests conducted aboard the NASA-sponsored aircraft follows the overview. Principal investigators and test engineers contributed significantly to the content of the report, describing their particular experiment or hardware evaluation. Although this document follows general guidelines, each report format may vary to accommodate differences in experiment design and procedures. This document concludes with an appendix that provides background information concerning the Reduced Gravity Program. Acknowledgment

Quality of experience in telemeetings and videoconferencing: a comprehensive survey

Telemeetings such as audiovisual conferences or virtual meetings play an increasingly important role in our professional and private lives. For that reason, system developers and service providers will strive for an optimal experience for the user, while at the same time optimizing technical and financial resources. This leads to the discipline of Quality of Experience (QoE), an active field originating from the telecommunication and multimedia engineering domains, that strives for understanding, measuring, and designing the quality experience with multimedia technology. This paper provides the reader with an entry point to the large and still growing field of QoE of telemeetings, by taking a holistic perspective, considering both technical and non-technical aspects, and by focusing on current and near-future services. Addressing both researchers and practitioners, the paper first provides a comprehensive survey of factors and processes that contribute to the QoE of telemeetings, followed by an overview of relevant state-of-the-art methods for QoE assessment. To embed this knowledge into recent technology developments, the paper continues with an overview of current trends, focusing on the field of eXtended Reality (XR) applications for communication purposes. Given the complexity of telemeeting QoE and the current trends, new challenges for a QoE assessment of telemeetings are identified. To overcome these challenges, the paper presents a novel Profile Template for characterizing telemeetings from the holistic perspective endorsed in this paper