pinecone/core-2020-05-10-deduplication huggingface dataset:
A Message Service for Opportunistic Computing in Disconnected MANETs

International audienceDisconnected mobile ad hoc networks (or D-MANETs) are partially or intermittently connected wireless networks in which instant end-to-end connectivity between any pair of mobile hosts is never guaranteed. Recent advances in delay/disruption-tolerant networking make it possible to support communication in such conditions, but designing and implementing distributed applications for D-MANETs is still a challenging task. Middleware systems such as the Java Message Service (JMS) have made application development easy and cost-effective in traditional wired networks. In this paper, we introduce JOMS (Java Opportunistic Message Service), a JMS provider specifically designed for D-MANETs, and with which pre-existing or new JMS-based applications can be easily deployed in such networks
Flexub: Dynamic subscriptions for publish/subscribe systems in MANETs

Current publish/subscribe systems provide very limited support to modify subscriptions dynamically. Consequently, they cannot efficiently control the flow of events between publishers and subscribers, which may lead to unnecessary network traffic. In addition, it is not possible to automatically subscribe or unsubscribe to a service depending on certain context of use. This implies for developers to manually manage subscriptions (e.g., taking care of when to cancel or re-issue a subscription), which may result in inappropriate subscription states (e.g., subscriptions that are cancelled too late). In this paper, we propose the concept of dynamic subscription mechanisms that improves the expressiveness and flexibility of subscriptions. We introduce a new dimension to a subscription that allows a subscriber to express the flow of matched events, and when a new subscription can be (re)issued. We validate our claims for improved flexibility and expressiveness by providing language abstractions and a prototype implementation of a dynamic subscription mechanism framework called Flexub that supports a variation of subscription mechanisms. When compared to existing subscription models, our experiment results show that the support for dynamic subscription mechanisms greatly reduces network traffic of events sent from publishers to the subscribers. In addition, our approach reduces the workload on the subscriber side.status: publishe
A middleware for pervasive situation-awareness

Situation-awareness is the ability of applications to adapt to the current situation of their users. For situation-awareness to be truly pervasive it should support the individual needs of every user, everywhere. We present a middleware for pervasive situation-awareness based on the idea of separating the features of a situation from the specification of how it should be recognised. The features of a situation can be seen as an interface that can be easily customised to satisfy individual user needs, while alternative specifications can be used to recognise a situation in different environments. The middleware views situations as collections of roles that individuals and devices play. Its implementation follows an agent-based architecture where collaborating agents acquire and reason over context data. We also show that the middleware can recognise a variety of highly customised situations using alternative specifications with performance that is acceptable for interactive situation-aware applications in realistic deployment sizes
Dissemination of reconfiguration policies on mesh networks

International audienceComponent-based platforms are widely used to develop and deploy distributed pervasive system that exhibit a high degree of dynam- icity, concurrency, distribution, heterogeneity, and volatility. This paper deals with the problem of ensuring safe yet efficient dynamic adaptation in a distributed and volatile environment. Most current platforms pro- vide capabilities for dynamic local adaptation to adapt these systems to their evolving execution context, but are still limited in their ability to handle distributed adaptations. Thus, a remaining challenge is to safely propagate reconfiguration policies of component-based systems to ensure consistency of the architecture configuration models over a dynamic and distributed system. In this paper we implement a specific algorithm rely- ing on the models at runtime paradigm to manage platform independent models of the current system architecture and its deployed configuration, and to propagate reconfiguration policies. We evaluate a combination of gossip-based algorithms and vector clock techniques that are able to propagate these policies safely in order to preserve consistency of archi- tecture configuration models among all computation nodes of the system. This evaluation is done with a test-bed system running on a large size grid network
Connecting your Mobile Shopping Cart to the Internet-of-Things

International audienceOnline shopping has reached an unforeseen success during the last decade thanks to the explosion of the Internet and the development of dedicated websites. Nonetheless, the wide diversity of e-commerce websites does not really foster the sales, but rather leaves the customer in the middle of dense jungle. In particular, finding the best offer for a specific product might require to spend hours browsing the Internet without being sure of finding the best deal in the end. While some websites are providing comparators to help the customer in finding the best offer meeting her/his requirements, the objectivity of these websites remains questionable, the comparison criteria are statically defined, while the nature of products they support is restricted to specific categories (e.g., electronic devices). In this paper, we introduce MACCHIATO as a user-centered platform leveraging online shopping. MACCHIATO implements the principles of the Internet-of-Things by adopting the REST architectural style and semantic web standards to navigate product databases exposed on the Internet. By doing so, customers keep the control of their shopping process by selecting the stores and comparing the offers according to their own preferences
Spectra: robust estimation of distribution functions in networks

Lecture Notes in Computer Science, Volume 7272, 2012.The distributed aggregation of simple aggregates such as minima/maxima, counts, sums and averages have been studied in the past and are important tools for distributed algorithms and network co- ordination. Nonetheless, this kind of aggregates may not be comprehen- sive enough to characterize biased data distributions or when in presence of outliers, making the case for richer estimates.
This work presents Spectra, a distributed algorithm for the estimation of distribution functions over large scale networks. The estimate is available at all nodes and the technique depicts important properties: robustness when exposed to high levels of message loss, fast convergence speed and fine precision in the estimate. It can also dynamically cope with changes of the sampled local property and with churn, without requiring restarts. The proposed approach is experimentally evaluated and contrasted to a competing state of the art distribution aggregation technique
Engineering a new loop-free shortest paths routing algorithm

International audienceWe present LFR (Loop Free Routing), a new loop-free distance vector routing algorithm, which is able to update the shortest paths of a distributed network with n nodes in fully dynamic scenarios. If Phi is the total number of nodes affected by a set of updates to the network, and phi is the maximum number of destinations for which a node is affected, then LFR requires O(Phi*Delta) messages and O(n + phi*Delta) space per node, where Delta is the maximum degree of the nodes of the network. We experimentally compare LFR with DUAL, one of the most popular loop-free distance vector algorithms, which is part of CISCO's EIGRP protocol and requires O(Phi*Delta) messages and Θ(n*Delta) space per node. The experiments are based on both real-world and artificial instances and show that LFR is always the best choice in terms of memory require- ments, while in terms of messages LFR outperforms DUAL on real-world instances, whereas DUAL is the best choice on artificial instances
Fully Dynamic Maintenance of Arc-Flags in Road Networks

International audienceThe problem of finding best routes in road networks can be solved by applying Dijkstra's shortest paths algorithm. Unfortunately, road networks deriving from real-world applications are huge yielding unsustainable times to compute shortest paths. For this reason, great research efforts have been done to accelerate Dijkstra's algorithm on road networks. These efforts have led to the development of a number of speed-up techniques, as for example Arc-Flags, whose aim is to compute additional data in a preprocessing phase in order to accelerate the shortest paths queries in an on-line phase. The main drawback of most of these techniques is that they do not work well in dynamic scenarios. In this paper we propose a new algorithm to update the Arc-Flags of a graph subject to edge weight decrease operations. To check the practical performances of the new algorithm we experimentally analyze it, along with a previously known algorithm for edge weight increase operations, on real-world road networks subject to fully dynamic sequences of operations. Our experiments show a significant speed-up in the updating phase of the Arc-Flags, at the cost of a small space and time overhead in the preprocessing phase
Dynamizing succinct tree representations

We consider succinct, or space-efficient, representations of ordinal trees. Representations exist that take 2n + o(n) bits to represent a static n-node ordinal tree - close to the information-theoretic minimum - and support navigational operations in O(1) time on a RAM model; and some implementations have good practical performance. The situation is different for dynamic ordinal trees. Although there is theoretical work on succinct dynamic ordinal trees, there is little work on the practical performance of these data structures. Motivated by applications to representing XML documents, in this paper, we report on a preliminary study on dynamic succinct data structures. Our implementation is based on representing the tree structure as a sequence of balanced parentheses, with navigation done using the min-max tree of Sadakane and Navarro (SODA '10). Our implementation shows promising performance for update and navigation, and our findings highlight two issues that we believe will be important to future implementations: the difference between the finger model of (say) Farzan and Munro (ICALP '09) and the parenthesis model of Sadakane and Navarro, and the choice of the balanced tree used to represent the min-max tree.Peer-reviewedPost-printProceedings of the 11th International Symposium, SEA 2012, Bordeaux, France, June 7-9, 2012
Implementation and Comparison of Heuristics for the Vertex Cover Problem on Huge Graphs

International audienceWe present in this paper an experimental study of six heuristics for a well-studied NP-complete graph problem: the vertex cover. These algorithms are adapted to process huge graphs. Indeed, executed on a current laptop computer, they offer reasonable CPU running times (between twenty seconds and eight hours) on graphs for which sizes are between 200 *106 and 100 *109 vertices and edges. We have run algorithms on specific graph families (we propose generators) and also on random power law graphs. Some of these heuristics can produce good solutions. We give here a comparison and an analysis of results obtained on several instances, in terms of quality of solutions and complexity, including running times
New results about multi-band uncertainty in Robust Optimization

"The Price of Robustness" by Bertsimas and Sim represented a breakthrough in
the development of a tractable robust counterpart of Linear Programming
Problems. However, the central modeling assumption that the deviation band of
each uncertain parameter is single may be too limitative in practice:
experience indeed suggests that the deviations distribute also internally to
the single band, so that getting a higher resolution by partitioning the band
into multiple sub-bands seems advisable. The critical aim of our work is to
close the knowledge gap about the adoption of a multi-band uncertainty set in
Robust Optimization: a general definition and intensive theoretical study of a
multi-band model are actually still missing. Our new developments have been
also strongly inspired and encouraged by our industrial partners, which have
been interested in getting a better modeling of arbitrary distributions, built
on historical data of the uncertainty affecting the considered real-world
problems. In this paper, we study the robust counterpart of a Linear
Programming Problem with uncertain coefficient matrix, when a multi-band
uncertainty set is considered. We first show that the robust counterpart
corresponds to a compact LP formulation. Then we investigate the problem of
separating cuts imposing robustness and we show that the separation can be
efficiently operated by solving a min-cost flow problem. Finally, we test the
performance of our new approach to Robust Optimization on realistic instances
of a Wireless Network Design Problem subject to uncertainty.Comment: 15 pages. The present paper is a revised version of the one appeared
  in the Proceedings of SEA 201
Analysing students' use of recorded lectures through methodological triangulation

Gorissen, P., Van Bruggen, J., & Jochems, W. M. G. (2012). Analysing students' use of recorded lectures through methodological triangulation. In L. Uden, E. S. Corchado Rodríquez, J. F. De Paz Santana, & F. De la Prieta (Eds.), Workshop on Learning Technology in Cloud (LTEC’12) (pp. 145-156). Heidelberg, New York, Dordrecht, London, Springer. doi:10.1007/978-3-642-30859-8Recorded lectures provide an integral recording of live lectures, enabling
students to review those lecture at their own pace and whenever they want. Most research
into the use of recorded lectures by students has been done by using surveys
or interviews. Our research combines this data with data logged by the recording
system. We will present the two data collections and cover areas where the data
can be triangulated to increase the credibility of the results or to question the student
responses. The results of the triangulation show its value, in that it identifies
discrepancies in the students' responses in particular where it concerns their perceptions
of the amount of use of the recorded lectures. It also shows that we lack
data for a number of other areas. We will still need surveys and interviews to get a
complete picture
ContextCare: Autonomous Video Surveillance System Using Multi-camera and Smartphones

Proceedings of: 1st International Symposium on Management Intelligent Systems (IS-MiS 2012), Salamanca,  July 11 -13, 2012.In the future, Ambient Intelligence (AmI) technology could assist people autonomously and interpret their intentions. Current technology can already be used to recognize the presence of a person in a private or public space and trigger an automatic response or reaction depending on the user activity. This work describes
ContextCare, an extension for an video surveillance system in a health care scenarios based on activity recognition using sensor smartphones. Both systems are coordinated using ECA parading.This work was supported in part by Projects CICYT TIN2011-28620-C02-01, CICYT
TEC2011-28626-C02-02, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029-C02-02Publicad
A novel agent-based framework in bridge-mode hypervisors of cloud security

Cloud computing has been introduced as a tool for improving IT proficiency and business responsiveness for organizations as it delivers flexible hardware and software services as well as providing an array of fundamentally systematized IT processes. Despite its many advantages, cloud computing security has been a major concern for organizations that are making the transition towards usage of this technology. In this paper, we focus on improving cloud computing security by managing and isolating shared network resources in bridge-mode hypervisors
QuPreSS: A service-oriented framework for predictive services quality assessment

Nowadays there are lots of predictive services for several domains such as stock market and bookmakers. The value delivered by these services relies on the quality of their predictions. This paper presents QuPreSS, a general framework which measures predictive service quality and guides the selection of the most accurate predictive service. To do so, services are monitored and their predictions are compared over time by means of forecast verification with observations. A systematic literature review was performed to design a service-oriented framework architecture that fits into the current body of knowledge. The service-oriented nature of the framework makes it extensible and interoperable, being able to integrate existing services regardless their heterogeneity of platforms and languages. Finally, we also present an instantiation of the generic framework architecture for the weather forecast domain, freely available at http://gessi.lsi.upc. edu/qupress/Peer ReviewedPostprint (author’s final draft
Organisational knowledge integration: towards a conceptual framework

This study analyses organisational knowledge integration processes from a multi-level and systemic perspective, with particular reference to the case of Fujitsu. A conceptual framework for knowledge integration is suggested focusing on team-building capability, capturing and utilising individual tacit knowledge, and communication networks for integrating dispersed specialist knowledge required in the development of new products and services. The research highlights that knowledge integration occurring in the innovation process is a result of knowledge exposure, its distribution and embodiment and finally its transfer, which leads to innovation capability and competitive advantage in firm
Preventing Arithmetic Overflows in Alloy

In a bounded analysis, arithmetic operators become partial, and a different semantics becomes necessary. One approach, mimicking programming languages, is for overflow to result in wrap-around. Although easy to implement, wrap-around produces unexpected counterexamples that do not correspond to cases that would arise in the unbounded setting. This paper describes a new approach, implemented in the latest version of the Alloy Analyzer, in which instances that would involve overflow are suppressed, and consequently, spurious counterexamples are eliminated. The key idea is to interpret quantifiers so that bound variables range only over values that do not cause overflow
Serious Game and Students’ Learning Motivation: Effect of Context Using Prog&Play

International audienceThis paper deals with an analysis of a large-scale use of Prog&Play , a game-based learning environment specially designed to teach the basics of programming to first year university students. The study relies mainly on a motivation survey completed by 182 students among 258 who used the serious game for 4 to 20 hours in seven different university settings. Our findings show that the students' interest for Prog&Play is not only related to the intrinsic game quality, it is also related to the teaching context and mainly to the course schedule and the way teachers organize sessions to benefit from the technology
Developing an embodied pedagogical agent with and for young people with autism spectrum disorder

This paper describes how we developed an embodied pedagogical agent (EPA) with and for young people with autism spectrum disorder (ASD). ASD is characterised by impairments in social communication, imagination, and perspective-taking, which can compromise design and collaboration. However, if an ASD preference for visual processing can be supported by providing images of design ideas as they develop, these difficulties may be overcome. We describe a methodology that successfully supports the visualisation and development of EPAs using our prototype visualisation tool (EPA DK), enabling ASD users to function as active design participants
Towards a privacy-respectful telematic verification system for vehicle & driver authorizations

Poster of: Eighth Annual International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MobiQuitous 2011), Copenhagen, Denmark, 2011The use of ubiquitous technologies to implement a telematic on-the-road verification of driver and vehicle authorizations would provide significant benefits regarding road safety, economic costs and convenience. Privacy-aware digital credentials would enable such a service although some challenges exist. The goal of this on-going work is to address these challenges. The first contribution herein presented is an enhanced data model of driver and vehicle authorizations. Secondly, we provide an analysis of existing privacy-aware digital credential systems that may support the implementation of the system.This work is partially supported by Ministerio de Ciencia e Innovacion of Spain, project E-SAVE, under grant TIN2009-13461.Publicad
A UML Extension for the Model-driven Specification of Audit Rules

In recent years, a number of laws and regulations (such as\ud
the Basel II accord or SOX) demand that organizations record certain\ud
activities or decisions to fulfill legally enforced reporting duties. Most of\ud
these regulations have a direct impact on the information systems that\ud
support an organization's business processes. Therefore, the definition of\ud
audit requirements at the modeling-level is an important prerequisite for\ud
the thorough implementation and enforcement of corresponding policies\ud
in a software system. In this paper, we present a UML extension for the\ud
specification of audit properties. The extension is generic and can be applied\ud
to a wide variety of UML elements. In a model-driven development\ud
(MDD) approach, our extension can be used to generate corresponding\ud
audit rules via model transformations. (author's abstract
Expressiveness and Understandability Considerations of Hierarchy in
  Declarative Business Process Models

Hierarchy has widely been recognized as a viable approach to deal with the
complexity of conceptual models. For instance, in declarative business process
models, hierarchy is realized by sub-processes. While technical implementations
of declarative sub-processes exist, their application, semantics, and the
resulting impact on understandability are less understood yet-this research gap
is addressed in this work. In particular, we discuss the semantics and the
application of hierarchy and show how sub-processes enhance the expressiveness
of declarative modeling languages. Then, we turn to the impact on the
understandability of hierarchy on a declarative process model. To
systematically assess this impact, we present a cognitive-psychology based
framework that allows to assess the possible impact of hierarchy on the
understandability of the process model