pinecone/core-2020-05-10-deduplication huggingface dataset:
Surfing Peer-to-Peer IPTV: Distributed Channel Switching

IPTV, Peer-to-Peer video streaming, network measurements, channel switchingInternational audienceIt is now common for IPTV systems attracting millions of users to be based on a peer-to-peer (P2P) architecture. In such systems, each channel is typically associated with one P2P overlay network connecting the users. This significantly enhances the user experience by relieving the source from dealing with all connections. Yet, the joining process resulting in a peer to be inte- grated in channel overlay usually requires a significant amount of time. As a consequence, switching from one channel to another is far to be as fast as in IPTV solutions provided by telco operators. In this paper, we tackle the issue of efficient channel switching in P2P IPTV system. This is to the best of our knowledge the first study on this topic. First, we conducted and analyzed a set of measurements of one of the most popular P2P systems (PPlive). These measurements reveal that the set of contacts that a joining peer receives from central server are of the utmost importance in the start-up process. On those neigbors, depends the speed to acquire the first video frames to play. We then formulate the switching problem, and propose a simple distributed algorithm, as an illustration of the concept, which aims at leveraging the presence of peers in the network to fasten the switch process. The principle is that each peer maintains as neighbors peers involved in other channels, providing peers with good contacts upon channel switching. Finally, simulations show that our ap- proach leads to substantial improvements on the channel switching time. As our algorithmic solution does not have any prerequisite on the overlays, it appears to be an appealing add-on for existing P2P IPTV systems
An Extension of the StarSs Programming Model for Platforms with Multiple GPUs

While general-purpose homogeneous multi-core architectures are becoming ubiquitous, there are clear indications that, for a number of important applications, a better performance/power ratio can be attained using specialized hardware accelerators. These accelerators require specific SDK or programming languages which are not always easy to program. Thus, the impact of the new programming paradigms on the programmer’s productivity will determine their success in the high-performance computing arena. In this paper we present GPU Superscalar (GPUSs), an extension of the Star Superscalar programming model that targets the parallelization of applications on platforms consisting of a general-purpose processor connected with multiple graphics processors. GPUSs deals with architecture heterogeneity and separate memory address spaces, while preserving simplicity and portability. Preliminary experimental results for a well-known operation in numerical linear algebra illustrate the correct adaptation of the runtime to a multi-GPU system, attaining notable performance results
Spatio-Temporal Modelling of Perfusion Cardiovascular MRI

Myocardial perfusion MRI provides valuable insight into how coronary artery and microvascular diseases affect myocardial tissue. Stenosis in a coronary vessel leads to reduced maximum blood flow (MBF), but collaterals may secure the blood supply of the myocardium but with altered tracer kinetics. To date, quantitative analysis of myocardial perfusion MRI has only been performed on a local level, largely ignoring the contextual information inherent in different myocardial segments. This paper proposes to quantify the spatial dependencies between the local kinetics via a Hierarchical Bayesian Model (HBM). In the proposed framework, all local systems are modelled simultaneously along with their dependencies, thus allowing more robust context-driven estimation of local kinetics. Detailed validation on both simulated and patient data is provided.
A robust lesion boundary segmentation algorithm using level set methods

This paper addresses the issue of accurate lesion segmentation in retinal imagery, using level set methods and\ud
a novel stopping mechanism - an elementary features scheme. Specifically, the curve propagation is guided\ud
by a gradient map built using a combination of histogram equalization and robust statistics. The stopping\ud
mechanism uses elementary features gathered as the curve deforms over time, and then using a lesionness\ud
measure, defined herein, ’looks back in time’ to find the point at which the curve best fits the real object.\ud
We compare the proposed method against five other\ud
segmentation algorithms performed on 50 randomly selected images of exudates with a database of clinician\ud
demarcated boundaries as ground truth
Texture classification of images from endoscopic capsule by using MLP and SVM – a comparative approach

This article reports a comparative study of Multilayer Perceptrons (MLP) and Support Vector Machines (SVM) in the classification of endoscopic capsule images. Texture information is coded by second order statistics of color image levels extracted from co-occurrence matrices. The co-occurrence matrices are computed from images rich in texture information. These images are obtained by processing the original images in the wavelet domain in order to select the most important information concerning texture description. Texture descriptors calculated from co-occurrence matrices are then modeled by using third and forth order moments in order to cope with non-Gaussianity, which appears especially in some pathological cases. Several color spaces are used, namely the most simple RGB, the most related to the human perception HSV, and the one that best separates light and color information, which uses luminance and color differences, usually known as YCbCr.Centre Algoritm
Topological SLAM Using Fast Vision Techniques

In this paper we propose a method for vision only topological simultaneous localisation and mapping (SLAM). \ud
Our approach does not use motion or odometric information but a sequence of colour histograms from visited places. In particular, we address the perceptual aliasing problem which occurs using external observations only in topological navigation.  \ud
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We propose a Bayesian inference method to incrementally build a topological map by inferring spatial relations from the sequence of observations while simultaneously estimating the robot's location. The algorithm aims to build a small map which is consistent with local adjacency information extracted from the sequence measurements. Local adjacency information is incorporated to disambiguate places which otherwise would appear to be the same.\ud
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Experiments in an indoor environment show that the proposed technique is capable of dealing with perceptual aliasing using visual observations only and successfully performs topological SLAM
Weighted decoding ECOC for facial action unit classification

There are two approaches to automating the task of facial expression recognition, the first concentrating on what meaning is conveyed by facial expression and the second on categorising deformation and motion into visual classes. The latter approach has the advantage that the interpretation of facial expression is decoupled from individual actions as in FACS (Facial Action Coding System). In this chapter, upper face action units (aus) are classified using an ensemble of MLP base classifiers with feature ranking based on PCA components. When posed as a multi-class problem using Error-Correcting-Output-Coding (ECOC), experimental results on Cohn-Kanade database demonstrate that error rates comparable to two-class problems (one-versus-rest) may be obtained. The ECOC coding and decoding strategies are discussed in detail, and a novel weighted decoding approach is shown to outperform conventional ECOC decoding. Furthermore, base classifiers are tuned using the ensemble Out-of-Bootstrap estimate, for which purpose, ECOC decoding is modified. The error rates obtained for six upper face aus around the eyes are believed to be among the best for this database
Structural change, economic growth and environmental dynamics with heterogeneous agents

This paper presents a model which takes into account two main factors that have been partially neglected by the economic development literature: the environmental externalities of human activities and agents' heterogeneity in terms of asset endowment and, consequently, in terms of income source and vulnerability to depletion of natural resources. This approach permits to shed light on agents' differences in feed-back mechanisms and interactions between their choices and environmental dynamics and allow us to propose a taxonomy of structural changes on the basis of distributive, environmental and economic impact. In such context, we identify under which conditions each structural change can occur. In par ticular, we identify new requirements for prompting positive structural changes, i.e. a movement of labour to capitalistic activities associated with poverty reduction and the alleviation of environmental pressures.
Expanding the Realm of Systematic Proof Theory

International audienceThis paper is part of a general project of developing a sys- tematic and algebraic proof theory for nonclassical logics. Generaliz- ing our previous work on intuitionistic-substructural axioms and single- conclusion (hyper)sequent calculi, we define a hierarchy on Hilbert ax- ioms in the language of classical linear logic without exponentials. We then give a systematic procedure to transform axioms up to the level P3 of the hierarchy into inference rules in multiple-conclusion (hy- per)sequent calculi, which enjoy cut-elimination under a certain con- dition. This allows a systematic treatment of logics which could not be dealt with in the previous approach. Our method also works as a heuristic principle for finding appropriate rules for axioms located at levels higher than P3 . The case study of Abelian and Lukasiewicz logic is outlined
On the word problem for SP-categories, and the properties of two-way communication

International audienceThe word problem for categories with free products and coproducts (sums), SP-categories, is directly related to the problem of determining the equivalence of certain processes. Indeed, the maps in these categories may be directly interpreted as processes which communicate by two-way channels. The maps of an SP-category may also be viewed as a proof theory for a simple logic with a game theoretic intepretation. The cut-elimination procedure for this logic determines equality only up to certain permuting conversions. As the equality classes under these permuting conversions are finite, it is easy to see that equality between cut-free terms (even in the presence of the additive units) is decidable. Unfortunately, this does not yield a tractable decision algorithm as these equivalence classes can contain exponentially many terms. However, the rather special properties of these free categories -- and, thus, of two-way communication -- allow one to devise a tractable algorithm for equality. We show that, restricted to cut-free terms s,t : X --> A, the decision procedure runs in time polynomial on |X||A|, the product of the sizes of the domain and codomain type
Linear Game Automata: Decidable Hierarchy Problems for Stripped-Down Alternating Tree Automata

For deterministic tree automata, classical hierarchies, like Mostowski-Rabin (or index) hierarchy, Borel hierarchy, or Wadge hierarchy, are known to be decidable. However, when it comes to non-deterministic tree automata, none of these hierarchies is even close to be understood. Here we make an attempt in paving the way towards a clear understanding of tree automata. We concentrate on the class of linear game automata (LGA), and prove within this new context, that all corresponding hierarchies mentioned above—Mostowski-Rabin, Borel, and Wadge—are decidable. The class LGA is obtained by taking linear tree automata with alternation restricted to the choice of path in the input tree. Despite their simplicity, LGA recognize sets of arbitrary high Borel rank. The actual richness of LGA is revealed by the height of their Wadge hierarchy: (ω^ω)^ω
Focalisation and Classical Realisability (version with appendices)

The original publication is avalaible at : www.springerlink.comInternational audienceWe develop a polarised variant of Curien and Herbelin's lambda-bar-mu-mu-tilde calculus suitable for sequent calculi that admit a focalising cut elimination (i.e. whose proofs are focalised when cut-free), such as Girard's classical logic LC or linear logic. This gives a setting in which Krivine's classical realisability extends naturally (in particular to call-by-value), with a presentation in terms of orthogonality. We give examples of applications to the theory of programming languages
Distinguishing regional from within-codon rate heterogeneity in DNA sequence alignments

We present an improved phylogenetic factorial hidden Markov model (FHMM) for detecting two types of mosaic structures in DNA sequence alignments, related to (1) recombination and (2) rate heterogeneity. The focus of the present work is on improving the modelling of the latter aspect. Earlier papers have modelled different degrees of rate heterogeneity with separate hidden states of the FHMM. This approach fails to appreciate the intrinsic difference between two types of rate heterogeneity: long-range regional effects, which are potentially related to differences in the selective pressure, and the short-term periodic patterns within the codons, which merely capture the signature of the genetic code. We propose an improved model that explicitly distinguishes between these two effects, and we assess its performance on a set of simulated DNA sequence alignments
Ant colony optimization and its application to the vehicle routing problem with pickups and deliveries

Ant Colony Optimization (ACO) is a population-based metaheuristic that can be used to find approximate solutions to difficult optimization problems. It was first introduced for solving the Traveling Salesperson Problem. Since then many implementations of ACO have been proposed for a variety of combinatorial optimization. In this chapter, ACO is applied to the Vehicle Routing Problem with Pickup and Delivery (VRPPD). VRPPD determines a set of vehicle routes originating and ending at a single depot and visiting all customers exactly once. The vehicles are not only required to deliver goods but also to pick up some goods from the customers. The objective is to minimize the total distance traversed. The chapter first provides an overview of ACO approach and presents several implementations to various combinatorial optimization problems. Next, VRPPD is described and the related literature is reviewed, Then, an ACO approach for VRPPD is discussed. The approach proposes a new visibility function which attempts to capture the “delivery” and “pickup” nature of the problem. The performance of the approach is tested using well-known benchmark problems from the literature
Goal programming models and DSS for manpower planning of airport baggage service

Goal Programming (GP) models and Decision Support System (DSS) are two powerful tools dealing with manpower planning problems, not only on research level, but also as practical tools for industrial implementation. Goal programming is often useful as an optimization modeling technique for generating shift-duties of worker schedules. In our project for the baggage service agency at the Hong Kong International Airport, we proposed three model formulations based on the basic fixed-length shift duties generation model to approach various combinations of goals of manpower planning. Such an optimization modeling is built upon the essential foundation of a detailed data modeling and its analysis for all the driving parameters and demand/supply input necessary for numerical computations. The data model and GP model thus form the two integral components of the overall automation system - the DSS, which is an automatic computer based and userfriendly system to support management on planning decisions © Springer Physica-Verlag Berlin Heidelberg 2010.postprin
Requirements for Supporting Individual Human Creativity in the Design Domain

International audienceCreativity is an important activity in many professional and leisure domains. This article presents a first step towards a system which will provide a set of tools for enhancing the individual creative abilities of the user in a design task. We have identified aspects which are characterise individual creativity: motivation, domain knowledge, externalization, inspiration and analogies, and requirements handling. Based on these aspects we have defined requirements and suggest associated system functionalities
Sonic Gestures Applied to a Percussive Dialogue in TanGram using Wii Remotes

TanGram, is an original music score composed by Carlos D. Perales for Percussion Quartet and Nintendo Wii Remotes used as a wireless interface for Live Electronics. This paper examines how this composition explores exiting research in interaction and communication between instruments and digital sound processing discourse to produce a unique music mixed-media score, to explore the sonic possibilities of a multi-timbrical instrument with the integration of the visual gestures of an accessible device using processes of real-time gestural mimesis.
Hardcore classification: identifying play styles in social games using network analysis

In the social network of a web-based online game, all players are not equal. Through network analysis, we show that the community of players in a online social game is an example of a scale free small world network and that the growth of the player-base obeys a power law. \ud
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The community is centred around a minority group of ``hardcore" players who define the social environment for the game, and without whom the social network would collapse. Methods are discussed for identifying this critically important subset of players automatically through analysing social behaviours within the game
Question: where would you go to escape detection if you wanted to do something illegal on the Internet? Hint: shush!

The background to this paper is the introduction of public access IT facilities in public libraries. These facilities have seen recorded instances of misuse alongside weaknesses in checking identities of users and in explaining Acceptable Use Policies (AUPs) to users. The FRILLS (Forensic Readiness of Local Libraries in Scotland) project, funded by the Scottish Library and Information Council, attempted to survey the situation in Scottish public libraries and develop a forensic readiness logging regime for use in them. There is in depth discussion of the use of logging in public library computer facilitie
International Civil Litigation and the Pollution of the Marine Environment

Whenever a major accident occurs to a ship – whether a fire or an explosion on board of the ship, or a collision with another ship, or the ship running aground or sinking and becoming a wreck – it is likely that this casualty will result in considerable physical damage to the ship and its cargo, and in some cases also in loss of life or personal injury to crew members and passengers aboard the ship. Obviously this may have huge financial implications for parties interested in ship and cargo and for crew members, passengers and their relatives. However, a maritime casualty not only affects parties involved in the ship's operation but also third parties. Depending on the circumstances of the incident and the nature of the resulting damage, (many) third parties from various countries are likely to suffer losses as well. A few examples may help to draw the picture. States may be affected, e.g. if wreck removal and clean-up operations become necessary, but also the financial interests and livelihoods of private individuals and businesses, such as local hotels and restaurants who lose earnings from tourists when the coast line becomes covered by a thick layer of crude oil or fisheries who temporarily or permanently lose access to their fishing grounds. Indirectly, the financial interests of many more parties will be affected by the disaster as its consequences ripple on through the local and national economy. This group includes the sub-buyers and final users of the goods as well as underwriters, whether Hull and Machinery (H&M) underwriters or Protection & Indemnity (P&I) insurers of the ship or marine cargo underwriters. Besides the multitude of interests likely to be affected by a maritime casualty involving a ship, there is also a potential for exceptional financial losses resulting from it. It was reported in 2008 that the costs of clean-up operations in Alaska following the Exxon Valdez oil spill in 1989 had reached the figure of US$ 3,5 billion and still counting. But not only oil tankers and ships carrying other hazardous cargoes are capable of generating such enormous losses. Modern container vessels with over 12,000 TEU capacity may easily have cargoes on board worth hundreds of millions of Euros, as is illustrated by the fires involving the m.v. “Hanjin Pennsylvania” in 2002 and the m.v. “Hyundai Fortune” in 2006, and the voluntary grounding of the “MSC Napoli” in 2007
A priori convergence estimates for a rough Poisson-Dirichlet problem with natural vertical boundary conditions

Dedicated to Professor Giovanni Paolo Galdi 60' BirthdayInternational audienceStents are medical devices designed to modify blood flow in aneurysm sacs, in order to prevent their rupture. Some of them can be considered as a locally periodic rough boundary. In order to approximate blood flow in arteries and vessels of the cardio-vascular system containing stents, we use multi-scale techniques to construct boundary layers and wall laws. Simplifying the flow we turn to consider a 2-dimensional Poisson problem that conserves essential features related to the rough boundary. Then, we investigate convergence of boundary layer approximations and the corresponding wall laws in the case of Neumann type boundary conditions at the inlet and outlet parts of the domain. The difficulty comes from the fact that correctors, for the boundary layers near the rough surface, may introduce error terms on the other portions of the boundary. In order to correct these spurious oscillations, we introduce a vertical boundary layer. Trough a careful study of its behavior, we prove rigorously decay estimates. We then construct complete boundary layers that respect the macroscopic boundary conditions. We also derive error estimates in terms of the roughness size epsilon either for the full boundary layer approximation and for the corresponding averaged wall law
Haptic Interaction Techniques for Exploring Chart Data

Haptic data visualization is a growing research area. It conveys information using the sense of touch which can help visually impaired people or be useful when other modalities are not available. However, as haptic devices and virtual worlds exhibit many challenges, the haptic interactions developed are often simple and limited to navigation tasks, preferring other modalities to relay detailed information. One of the principal challenges of navigation with haptic devices alone, particularly single point-based force-feedback devices, is that users do not know where to explore and thus obtaining an overview is difficult. Thus, this paper presents two types of interaction technique that aim to help the user get an overview of data: 1) a haptic scatter plot, which has not been investigated to any great degree, provided by a force model and 2) a new implementation for a haptic line chart technique provided using a guided tour model