Optimal transmission policies for energy harvesting communication devices

Energy Harvesting (EH) is a new paradigm in Wireless Sensor Networks (WSNs): sensor nodes are powered by energy harvested from the ambient, rather than by non-rechargeable batteries, thus enabling a potentially perpetual operation of the WSN. However, Energy Harvesting poses new challenges in the design of WSNs, in that energy availability is random and fluctuates over time, thus calling for radically different energy management solutions. In this talk we investigate the following fundamental question: how should the harvested energy be managed to ensure optimal performance? First, we consider a sensor powered by EH which senses data of varying importance and reports them judiciously to a Fusion Center. Assuming that data transmission incurs an energy cost, our objective is to identify low-complexity policies that achieve close-to-optimal performance, in terms of maximizing the average long-term importance of the reported data. We first consider schemes that rely on the assumption of perfect knowledge of the amount of energy available in the battery. Subsequently, we investigate the design of operation policies that maximize the long-term reward under imperfect knowledge of the State-Of-Charge (SOC). Moreover, for both scenarios, we explore the impact of time-correlation in the EH process, showing that simple adaptation to the state of the EH process yields close-to-optimal performance, without requiring full knowledge of the SOC of the battery.

Michele Zorzi is a Professor at the Department of Information Engineering of the University of Padova. Prior to his current appointment, he was employed at the Politecnico di Milano, the University of Ferrara and the University of California at San Diego, with which he still has an active collaboration. He is an IEEE Fellow. His main research interests are in the area of wireless communications and networking, sensor networks and IoT, underwater communications and networks, cognitive networking, and energy-efficient protocol design. His work is widely cited, with a total of more than 11000 citations and an h-index of 52.

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Humanistische Pädagogik begegnet Informatik und Internet – welcher Mehrwert kann aus dieser Begegnung für Lernende und Lehrende erwachsen?

In diesem Vortrag wird das Wesen, die Entwicklung, Praxis und Erforschung von personzentriertem, technologie-erweitertem Lernen (PCeL) vorgestellt. PCeL integriert die zwischenmenschlichen Grundhaltungen des Personzentrierten Ansatzes nach Carl Rogers mit einem abgestimmten, förderlichen Einsatz web-basierter Technologien.  PCeL wurde von der Vortragenden und ihrem Team an der Universität Wien entwickelt und erprobt. Während es auf der eigenen Praxis in Informatik- und Fachdidaktik- Lehrveranstaltungen basiert, wurde PCeL für den Unterricht in der Sekundarstufe II adaptiert und begleitend erforscht.  Lehr-/Lernerfahrungen im Kontext der Informatik werden diskutiert.

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Entwicklungsperspektiven der Informatikdidaktik

Die zunehmende unreflektierte Nutzung digitaler Medien und Geräte bewirkt, dass gerade bei jungen Menschen Fehlvorstellungen darüber, was Informatik ist, zunehmen. Im ersten Teil des Vortrages wird eine Initiative zur Vermeidung solcher Fehlvorstellungen durch medienreduzierte Integration informatischer Kerninhalte in den Unterricht der Primarstufe vorgestellt. Kinder der Primarstufe lernen altersadäquat die Konzepte der Algorithmisierung und Automatisierung kennen, wobei an bestehende Lern- und Unterrichtsmuster der Primarstufe angeschlossen wird. Der zweite Teil des Vortrages geht auf Perspektiven für die Weiterentwicklung der Informatikdidaktik ein, die sich im Kontext der beginnenden Zusammenarbeit von Universitäten und Pädagogischen Hochschulen im Verbund Süd-Ost aus solchen Initiativen ergeben.

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Visual Processing with Humans in the Loop

Abstract: It is now well known that many problems in image understanding and multimedia content analysis can benefit from human computations and crowdsourcing techniques. In this talk, we’ll first examine a few influential works from the literature where explicit tasks are performed by motivated workers (through altruistic incentives or personal enjoyment) and then combined with content analysis methods. In the second part of the presentation, our recent results on ‘zoomable video players’ will be briefly presented. These examples particularly highlight the use of implicit tasks to naturally infer knowledge about the visual or multimedia content.Charvillat

Short-CV: Vincent CHARVILLAT received the Eng. degree in Computer Science and Applied Mathematics from ENSEEIHT, Toulouse France and the M.Sc. in Computer Science  from the National Polytechnic Institute of Toulouse, both in 1994. He received the Ph.D. degree in Computer Science from the National Polytechnic Institute of Toulouse in 1997. He is currently a full professor at the University of Toulouse, IRIT research lab, ENSEEIHT Eng. School. Vincent CHARVILLAT is the head of  VORTEX research team at ENSEEIHT. His main research interests are visual processing and multimedia applications. Current topics of research include visual object processing, visual compositing, visual interaction design and crowdsourcing in multimedia.

 

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Adaptation of video contents and perception quality

Abstract:

The ubiquitous access to the Web and, more generally to digital contents has dramatically changed the “digital experience” everyone daily lives. However, the diversity of contexts (technical contexts, social contexts, personal contexts), the diversity of users, the diversity of digital contents have definitely made mandatory the (or at least, some) personalization of the users’ experience.
The notion of “Universal Multimedia Experience (UME)” has been coined to represent this attempt to put the user at the center of the content delivery process. The key idea that underpins this concept is the notion of adaptation: adaptation of the delivery process to the network conditions, adaptation of the type of content to the user’s preferences and profile, adaptation of the content itself to the user’s terminal capabilities and user’s activity, etc.
This talk will address some of the key issues related to multimedia content adaptation and multimedia quality of experience.
First, we will focus on the modeling of the user’s context. Indeed, a basic condition to adaptation is the capture (or the inference) and the representation of the user’s “context” i.e., the technical conditions (network, terminal), the user’s activity, the user’s intention, the user’s profile and preferences.
Then, the core of the talk will be dedicated to the specific issues of video content adaptation. By their isochronous nature; by the richness and complexity of the information they carry; by the multiplicity of their stakeholders (end user, creator, video broadcaster), video contents raise specific and complex issues related to both semantic, perceptual and even legal constraints and conflicts.
To address these issues, we will introduce the concept of Utility Function, which aims at integrating in one multi-dimensional optimization space, semantic constraints, user’s context characteristics and perceptual considerations.
As a side effect of this modeling of the video adaptation process, we will analyze how the enforcement of access control rules on video contents can be formalized as a problem of content adaptation.
Finally, we will investigate some still open issues related to video delivery optimization in P2P and delay-tolerant networks, complex multi-dimensional semantic constraints, visual aesthetics, privacy and security.
This talk will be illustrated by research works developed in the International Doctoral College and Federative Laboratory “Multimedia Distributed and Pervasive Secure Systems” (MDPS) which comprises researchers from the National Institute of Applied Sciences (INSA) of Lyon, France (Pr. L. Brunie’s team), the University of Passau (Pr. H. Kosch’s team), Germany and the University of Milan, Italy (Pr. E. Damiani’s team).

CV:

Lionel Brunie is full professor at the National Institute of Applied Sciences (INSA) of Lyon, France, where he leads the LIRIS DRIM research team.
With 10 permanent researchers and 15+ PhD students, the DRIM team is specialized in distributed data management, multimedia information systems, information retrieval, and sec
photo Lionel juillet 2012urity/privacy.
In 2007, along with Pr Harald Kosch (University of Passau, Germany), Lionel Brunie created the French-German doctoral college in “Multimedia Distributed and Pervasive Secur
e Systems (MDPS)”. MDPS was extended in 2009 to the University of Milan, Italy (Pr. Ernesto Damiani’s team). MDPS proposes both a framework for international co-supervised PhDs and a federative research institute that develops a joint research agenda.
Lionel Brunie’s main topics of interest include: data management in large scale and pervasive systems, collaborative multimedia information systems, security and privacy, e-health applications.

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Intelligent Agile Method Framework

Abstract:

The use of software development methods (SDM) in software industry proves beneficial as it contributes to higher quality of both, the process and its product, i.e. the developed software. Despite these evident benefits, the studies on the maturity of the software development discipline show that a large percent of software development companies do not have their SDMs documented and those that have, do not really follow them or do not follow them rigorously. This problem has been recognized as one of the key reasons for failures in software development projects and a contributor to the low quality of software. In this talk I will introduce a novel approach that could help to improve the maturity of software development processes. The approach is based on the method engineering principles taking into account the limitations that hinder its use in practice. The main objective of our research is to show that the method engineering concepts which have been developed in the last few decades but never really penetrated to practice are applicable in real settings and that could contribute to software industry.

About the Speaker:

Marko Bajec is an Associate Professor at the University of Ljubljana, Faculty of Computer and Information Science. He is a member of the Department for Informatics where he delivers courses on Information Systems and Databases. Marko’s research interests mostly focus on IS Development and IT Governance. Since 2009, he has been on the position of the Head of the Laboratory for Data Technologies where he manages research in data technologies in relation to IS development and management. In his past research Marko has developed different approaches and methods that help measuring, formalizing, and improving software development processes. For his achievements in transferring knowledge to industry he has got several awards and recognitions. Marko Bajec is vice-president of Slovenian society INFORMATICA and Slovenian representative of IFIP TC 2 – Software: Theory and Practice. He is also a founder and co-owner of the university spin-off Optilab, which has become the leading Slovenian provider of solutions and services for fraud management in the insurance business.

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Using games to improve computer vision solutions

Abstract:
There are many challenging problems in computer vision for which state-of-the-art solutions fall short of performing perfectly. The realization that many of these tasks are arduous for computers yet are relatively easy for humans has inspired many researchers to approach those problems from a human computation viewpoint, using methods that include crowdsourcing and games – often called ‘games with a purpose’ (GWAPs). The talk discusses how we can use human computation (in general) and particularly games to help uncover hidden aspects of visual perception and use these findings to improve computer vision solutions to related problems. It particularly highlights two examples of our recent work on the topic:
1.   Guess That Face (with Mathias Lux and Justyn Snyder, CHI 2013): a face recognition game that reverse engineers the human biological threshold for accurately recognizing blurred faces of celebrities under time-varying conditions.
2.   Ask’N’Seek (with Vincent Charvillat and Axel Carlier, ECCV 2012): an object detection and labeling game that asks users to guess the location of a hidden region within an image with the help of semantic and topological clues and uses the information collected from game logs, combined with results from content analysis algorithms, to feed a machine learning algorithm that outputs the outline of the most relevant regions within the image and their names.

Short CV:
Oge Marques is an Associate Professor in the Department of Computer & Electrical Engineering and Computer Science at Florida Atlantic University (FAU) (Boca Raton, Florida). He received his Ph.D. in Computer Engineering from FAU in 2001. He has more than 20 years of teaching and research experience in the fields of image processing and computer vision, in different countries (U.S., Austria, Brazil, Netherlands, Spain, France, and India), languages (English,Portuguese,Spanish), and capacities.He is the (co-) author of more than 50 refereed journal and conference papers and several books in these topics, including the textbook Practical Image and Video Processing UsingMATLAB (Wiley, 2011). His research interests are in the area of intelligent processing of visual information, which combines the fields of image processing, computer vision, image retrieval, machine learning, serious games, and human visual perception. He is particularly interested in the combination of human computation and machine learning techniques to solve computer vision problems.

He is a senior member of both the ACM and IEEE, and a member of the IEEE Computer Society, IEEE Education Society, IEEE Signal Processing Society, and the honor societies of Tau Beta Pi, Sigma Xi, Phi Kappa Phi, and Upsilon Pi Epsilon.

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Notes on teaching software testing

The talk deals with two questions related to software testing. The first is: Why more testing should be taught? Complex systems and demands for higher software quality require software quality assurance, and generally, more efforts on software testing. The amount of software testing continues to grow. The related literature estimates that software testing effort is 50-60% of the total development effort. We summarize experience of teaching software testing by application of the ISTQB (International Software Testing Qualifications Board) syllabi in the master study programme of software
at ladislav.samuelis@tuke.sk.

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Action-driven design of user interfaces

The talk will provide an outline of major model-driven engineering approaches to user interface design: we will cover data-driven approaches as well as task-driven ones, highlighting what are the key requirements for modern rich Internet applications, and why many of those approaches are suboptimal in terms of usability and design process.
The action-driven design approach will be then described, together with the basic design principles it rests upon. The UML-IDEA methodology will be introduced, which is based on using UML state machines and UML classes to provide the building blocks for automatically assembling widgets, data and control logic into an executable user interface. Several examples will be illustrated, and the equation Controller + Model = View will be discussed.
The overall claim will be that UML-IDEA supports a clear meaning for the term „interaction design“ whose operationalization should bring a number of advantages: rapid and flexible mix-fidelity prototyping, retargeting of the user interface, usability metrics and development of functional test cases.

Giorgio Brajnik is assistant professor in Computer Science at the University of Udine, Italy. His current interests are design, development and quality assessments of user interfaces, with an emphasis on accessibility, usability and user experience. In the past he worked on tools for testing accessibility, as well as information retrieval user interfaces and qualitative modeling of dynamical systems. He currently teaches „Usage centered design of web applications“ and „User experience“. He has been invited several times as visiting professor or panelist, and is member of many conference program committees as well as being a reviewer for different journals. In the past he served as scientific advisor for companies; in July 2012 he cofounded and is President of Interaction Design Solutions, a spin-off of the University of Udine that develops software for rapid prototyping and multiplatform deployment of user interfaces based on innovative model-based development practices. The company also provides consultancy services regarding usability and usage-centered design.

 

 

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On Optimal and Achievable Cost/Delay Tradeoffs in Delay Tolerant Networks

ABSTRACT: Tradeoffs between the packet delivery delay and other metrics are a recurring theme in Delay Tolerant Networks (DTNs). In this work we study these tradeoffs, first in a general, and then in a more specific, mobile wireless setting. We first develop a general setting in which the packet delivery delay can be traded off with a packet transportation cost that is comprised of a transmission cost and a storage cost. We capture this tradeoff on the cost-delay plane using Optimal Cost/Delay Curves (OC/DCs), for the case where the nodes route packets optimally, and Achievable Cost/Delay Curves (AC/DCs), for the case where the nodes route packets according to a suboptimal routing protocol. We then apply this framework to mobile wireless DTNs. We develop a class of geographic routing protocols with delay-tolerant features and we compare them with other state-of-the-art routing protocols, using their respective AC/DCs, and with the performance achieved with optimal routing, in terms of the OC/DC. Our protocols are shown to achieve cost/delay tradeoffs much closer to the optimal one than all other protocols we examine.

BIO: Stavros Toumpis received the Diploma in Electrical and Computer Engineering from the National Technical University of Athens, Greece, in 1997, the M.S. degrees in Electrical Engineering and Mathematics from Stanford University, CA, in 1999 and 2002, espectively, and the Ph.D. degree in Electrical Engineering, also from Stanford, in 2003. From 1998 to 1999 he worked as a Research Assistant for the Mars Global Surveyor Radio Science Team, providing operational support. From 2000 to 2003 he was a Member of the Wireless Systems Laboratory, at Stanford University. From 2003 to 2005 he was a Senior Researcher with the Telecommunications Research Center Vienna (ftw.), in Vienna, Austria. From 2005 to 2009 he was a Lecturer at the Electrical and Computer Engineering Department of the University of Cyprus. Starting from 2009, he is an Assistant Professor in the Computer Science Department of the Athens University of Economics and Business. His research is on wireless ad hoc networks, with emphasis on their capacity, the effects of mobility on their performance, medium access control, and information theoretic issues.

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