pinecone/core-2020-05-10-deduplication huggingface dataset:
Multi-subject dictionary learning to segment an atlas of brain spontaneous activity

International audienceFluctuations in brain on-going activity can be used to reveal its intrinsic functional organization. To mine this information, we give a new hierarchical probabilistic model for brain activity patterns that does not require an experimental design to be specified. We estimate this model in the dictionary learning framework, learning simultaneously latent spatial maps and the corresponding brain activity time-series. Unlike previous dictionary learning frameworks, we introduce an explicit difference between subject-level spatial maps and their corresponding population-level maps, forming an atlas. We give a novel algorithm using convex optimization techniques to solve efficiently this problem with non-smooth penalties well-suited to image denoising. We show on simulated data that it can recover population-level maps as well as subject specificities. On resting-state fMRI data, we extract the first atlas of spontaneous brain activity and show how it defines a subject-specific functional parcellation of the brain in localized regions
A generative approach for image-based modeling of tumor growth

Extensive imaging is routinely used in brain tumor patients to monitor the state of the disease and to evaluate therapeutic options. A large number of multi-modal and multi-temporal image volumes is acquired in standard clinical cases, requiring new approaches for comprehensive integration of information from different image sources and different time points. In this work we propose a joint generative model of tumor growth and of image observation that naturally handles multi-modal and longitudinal data. We use the model for analyzing imaging data in patients with glioma. The tumor growth model is based on a reaction-diffusion framework. Model personalization relies only on a forward model for the growth process and on image likelihood. We take advantage of an adaptive sparse grid approximation for efficient inference via Markov Chain Monte Carlo sampling. The approach can be used for integrating information from different multi-modal imaging protocols and can easily be adapted to other tumor growth models.22nd International Conference, IPMI 2011, Kloster Irsee, Germany, July 3-8, 2011. ProceedingsGerman Academy of Sciences Leopoldina (Fellowship Programme LPDS 2009-10)Academy of Finland (133611)National Institutes of Health (U.S.) (NIBIB NAMIC U54-EB005149)National Institutes of Health (U.S.) (NCRR NAC P41- RR13218)National Institutes of Health (U.S.) (NINDS R01-NS051826)National Institutes of Health (U.S.) (NIH R01-NS052585)National Institutes of Health (U.S.) (NIH R01-EB006758)National Institutes of Health (U.S.) (NIH R01-EB009051)National Institutes of Health (U.S.) (NIH P41-RR014075)National Science Foundation (U.S.) (CAREER Award 0642971
Perceived multimedia quality: The impact of device characteristics

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2011 Springer VerlagIn the study reported in this paper, the research aims to tackle the question “Do the hardware characteristics of a device affect the viewer’s perceived quality of the media?” Using different hardware devices and media clips that have had different frame rates the viewer’s information assimilation and satisfaction of the media clip was measured. The results suggest that there is a deeper link between the user’s information assimilation than just the hardware that the media is viewed on. On the other hand a user’s satisfaction with clip quality is affected by the alterations in frame rate of the media rather than the device as the satisfaction levels increased regardless of the hardware characteristics
Smoothing a program soundly and robustly

We study the foundations of smooth interpretation, a recently-proposed program approximation scheme that facilitates the use of local numerical search techniques (e.g., gradient descent) in program analysis and synthesis. While the popular techniques for local optimization works well only on relatively smooth functions, functions encoded by real-world programs are infested with discontinuities and local irregular features. Smooth interpretation attenuates such features by taking the convolution of the program with a Gaussian function, effectively replacing discontinuous switches in the program by continuous transitions. In doing so, it extends to programs the notion of Gaussian smoothing, a popular signal-processing technique used to filter noise and discontinuities from signals.
Exact Gaussian smoothing of programs is undecidable, so algorithmic implementations of smooth interpretation must necessarily be approximate. In this paper, we characterize the approximations carried out by such algorithms. First, we identify three correctness properties—soundness, robustness, and β-robustness—that an approximate smooth interpreter should satisfy. In particular, a smooth interpreter is sound if it computes an abstraction of a program’s “smoothed” semantics, and robust if it has arbitrary-order derivatives in the input variables at every point in its input space. Second, we describe the design of an approximate smooth interpreter that provably satisfies these properties. The interpreter combines program abstraction using a new domain with symbolic calculation of convolution.National Science Foundation (U.S.) (Grant CCF-0953507)Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laborator
Are There Age Spreads in Star Forming Regions?

A luminosity spread at a given effective temperature is ubiquitously seen in
the Hertzsprung-Russell (HR) diagrams of young star forming regions and often
interpreted in terms of a prolonged period (>=10 Myr) of star formation. I
review the evidence that the observed luminosity spreads are genuine and not
caused by astrophysical sources of scatter. I then address whether the
luminosity spreads necessarily imply large age spreads, by comparing HR diagram
ages with ages from independent clocks such as stellar rotation rate, the
presence of circumstellar material and lithium depletion. I argue that whilst
there probably is a true luminosity dispersion, there is little evidence to
support age spreads larger than a few Myr. This paradox could be resolved by
brief periods of rapid accretion during the class I pre main-sequence phase.Comment: To appear in the proceedings of JENAM10: Star Clusters in the Era of
  Large Surveys, 8 page
Schemata of SMT problems

Session 3 (full paper)International audienceA logic is devised for reasoning about iterated schemata of SMT problems. The satisfiability problem is shown to be undecidable for this logic, but we present a proof procedure that is sound, complete w.r.t. satisfiability and terminating for a precisely characterized class of problems. It is parameterized by an external procedure (used as a black box) for testing the satisfiability of ground instances of the schema in the considered theory (e.g. integers, reals etc.)
Longitude : a privacy-preserving location sharing protocol for mobile applications

Location sharing services are becoming increasingly popular. Although many location sharing services allow users to set up privacy policies to control who can access their location, the use made by service providers remains a source of concern. Ideally, location sharing providers and middleware should not be able to access users’ location data without their consent. In this paper, we propose a new location sharing protocol called Longitude that eases privacy concerns by making it possible to share a user’s location data blindly and allowing the user to control who can access her location, when and to what degree of precision. The underlying cryptographic algorithms are designed for GPS-enabled mobile phones. We describe and evaluate our implementation for the Nexus One Android mobile phone
The meaning of success for software SMEs: An holistic scorecard based approach

Software processes support the work of software development and software process improvement (SPI) is concerned with improving the operation of the software process. One of the primary reasons for conducting SPI is to increase the success of a software development company [1], [2]. However, a lack of evidence of the benefits of SPI is reported as a de-motivator for project/senior managers [3]. Therefore, the case for SPI would benefit from evidence of the positive impact of SPI on business success. This paper proposes a new approach that utilises the Holistic Scorecard (HSC) [4] to systematically examine business success in software development companies. Furthermore, we relate the experience of applying this new approach to software small to medium sized enterprises (SMEs)
Gathering of Six Robots on Anonymous Symmetric Rings

International audienceThe paper deals with a recent model of robot-based computing which makes use of identical, memoryless mobile robots placed on nodes of anonymous graphs. The robots operate in Look-Compute-Move cycles; in one cycle, a robot takes a snapshot of the current configuration (Look), takes a decision whether to stay idle or to move to one of its adjacent nodes (Compute), and in the latter case makes an instantaneous move to this neighbor (Move). Cycles are performed asynchronously for each robot. In particular, we consider the case of only six robots placed on the nodes of an anonymous ring in such a way they constitute a symmetric placement with respect to one single axis of symmetry, and we ask whether there exists a strategy that allows the robots to gather at one single node. This is in fact the first case left open after a series of papers [1,2,3,4] dealing with the gathering of oblivious robots on anonymous rings. As long as the gathering is feasible, we provide a new distributed approach that guarantees a positive answer to the posed question. Despite the very special case considered, the provided strategy turns out to be very interesting as it neither completely falls into symmetry-breaking nor into symmetry-preserving techniques
An archetype-based solution for the interoperability of computerised guidelines and electronic health records

Clinical guidelines contain recommendations based on the best empirical evidence available at the moment. There is a wide con- sensus about the benefits of guidelines and about the fact that they should be deployed through clinical information systems, making them available during consultation time. However, one of the main obstacles to this integration is still the interaction with the electronic health record. In this paper we present an archetype-based approach to solve the inter- operability problems of guideline systems, as well as to enable guideline sharing. We also describe the knowledge requirements for the develop- ment of archetype-enabled guideline systems, and then focus on the de- velopment of appropriate guideline archetypes and on the connection of these archetypes to the target electronic health record
A Semantic Web Annotation Tool for a Web-Based Audio Sequencer

Music and sound have a rich semantic structure which is so clear to the composer and the listener, but that remains mostly hidden to computing machinery. Nevertheless, in recent years, the introduction of software tools for music production have enabled new opportunities for migrating this knowledge from humans to machines. A new generation of these tools may exploit sound samples and semantic information coupling for the creation not only of a musical, but also of a "semantic" composition. In this paper we describe an ontology driven content annotation framework for a web-based audio editing tool. In a supervised approach, during the editing process, the graphical web interface allows the user to annotate any part of the composition with concepts from publicly available ontologies. As a test case, we developed a collaborative web-based audio sequencer that provides users with the functionality to remix the audio samples from the Freesound website and subsequently annotate them. The annotation tool can load any ontology and thus gives users the opportunity to augment the work with annotations on the structure of the composition, the musical materials, and the creator's reasoning and intentions. We believe this approach will provide several novel ways to make not only the final audio product, but also the creative process, first class citizens of the Semantic We
Environmental Information Systems on the Internet: A Need for Change

The cost effective delivery of scientific and policy requirements is a key driver for the realization of global sustainability research, integrated assessment and supporting innovative systems. The next generation of geospatial information infrastructures is proposed as a possible solution. Still, questions such as ‘what does all this mean to environmental information systems’ and ‘what is expected to change’, have only partially been answered. In this paper, we describe the recent challenges for eEnvironment services in Europe, specify desired capabilities and derive according requirements. We identify affected stakeholder communities and depict their involvement in the overall value chain of environmental knowledge generation. Specific examples illustrate individual needs, while a derived description of the value chain indicates more general outcomes. Developmental requirements of future information systems are discussed. The presented work answers the questions above by bridging the gab between stakeholder needs, Information and Communication Technology (ICT) development and higher level concepts, such as Digital Earth and Future  Internet.JRC.DDG.H.6-Spatial data infrastructure
Open Environmental Platforms: Top-Level Components and Relevant Standards

We present our ideas of an open Information and Communication Technology (ICT) platform for monitoring, mapping and managing our environment. The envisioned solution bridges the gap between the Internet of Things, Content and Services, and highly specific applications, such as oil spill detection or marine monitoring. On the one hand, this environmental platform should be open to new technologies; on the other hand, it has to provide open standard interfaces to various application domains. We identify core components, standards, and needs for new standard development in ICT for environment. We briefly outline how our past and present activities contribute to the development of the desired open environmental platform. Future implementations shall contribute to sustainable developments in the environmental domain.JRC.DDG.H.6-Spatial data infrastructure
Architecture of a pan-European framework for Integrated Soil Water Erosion Assessment

Soil erosion implications on future food security are gaining global attention because in many areas worldwide there is an imbalance between soil loss and its subsequent deposition. Soil erosion is a complex phenomenon affected by many factors such as climate, topography and land cover (in particular forest resources, natural vegetation and agriculture) while directly influencing water sediment transport, the quality of water resources and water storage loss. A modeling architecture, based on the Revised Universal Soil Loss Equation, is proposed and applied to evaluate and validate at regional scale potential and actual soil water erosion, enabling it to be linked to other involved natural resources. The methodology benefits from the array programming paradigm with semantic constraints (lightweight array behavioural contracts provided by the Mastrave library) to concisely implement models as composition of interoperable modules and to process heterogeneous data.JRC.H.3-Forest Resources and Climat
Lossless fault-tolerant data structures with additive overhead

We develop the first dynamic data structures that tolerate δ memory faults, lose no data, and incur only an O(δ ) additive overhead in overall space and time per operation. We obtain such data structures for arrays, linked lists, binary search trees, interval trees, predecessor search, and suffix trees. Like previous data structures, δ must be known in advance, but we show how to restore pristine state in linear time, in parallel with queries, making δ just a bound on the rate of memory faults. Our data structures require Θ(δ) words of safe memory during an operation, which may not be theoretically necessary but seems a practical assumption.12th International Symposium, WADS 2011, New York, NY, USA, August 15-17, 2011. ProceedingsCenter for Massive Data Algorithmics (MADALGO
Flattening fixed-angle chains is strongly NP-hard

Planar configurations of fixed-angle chains and trees are well studied in polymer science and molecular biology. We prove that it is strongly NP-hard to decide whether a polygonal chain with fixed edge lengths and angles has a planar configuration without crossings. In particular, flattening is NP-hard when all the edge lengths are equal, whereas a previous (weak) NP-hardness proof used lengths that differ in size by an exponential factor. Our NP-hardness result also holds for (nonequilateral) chains with angles in the range [60° − ε,180°], whereas flattening is known to be always possible (and hence polynomially solvable) for equilateral chains with angles in the range (60°,150°) and for general chains with angles in the range [90°,180°]. We also show that the flattening problem is strongly NP-hard for equilateral fixed-angle trees, even when every angle is either 90° or 180°. Finally, we show that strong NP-hardness carries over to the previously studied problems of computing the minimum or maximum span (distance between endpoints) among non-crossing planar configurations.12th International Symposium, WADS 2011, New York, NY, USA, August 15-17, 2011. Proceeding
Flow computations on imprecise terrains

We study water flow computation on imprecise terrains. We\ud
consider two approaches to modeling flow on a terrain: one where water\ud
flows across the surface of a polyhedral terrain in the direction of steepest\ud
descent, and one where water only flows along the edges of a predefined\ud
graph, for example a grid or a triangulation. In both cases each vertex has\ud
an imprecise elevation, given by an interval of possible values, while its\ud
(x, y)-coordinates are fixed. For the first model, we show that the problem\ud
of deciding whether one vertex may be contained in the watershed of\ud
another is NP-hard. In contrast, for the second model we give a simple\ud
O(n log n) time algorithm to compute the minimal and the maximal\ud
watershed of a vertex, where n is the number of edges of the graph.\ud
On a grid model, we can compute the same in O(n) time.Peer ReviewedPostprint (published version
A Verification-Based Approach to Memory Fence Insertion in Relaxed Memory Systems

This paper addresses the problem of verifying and correcting programs when they
are moved from a sequential consistency execution environment to a relaxed
memory context. Specifically, it considers the TSO (Total Store Order) 
relaxation, which corresponds to the use of store buffers, and its extension
x86-TSO, which in addition allows synchronization and lock operations.

The proposed approach uses a previously developed verification tool that uses
finite automata to symbolically represent the possible contents of the store
buffers. Its starting point is a program that is correct for the usual
sequential consistency memory model, but that might be incorrect under x86-TSO.
This program is then analyzed for this relaxed memory model and when errors are
found (with respect to safety properties), memory fences are inserted in order
to avoid these errors. The approach proceeds iteratively and heuristically,
inserting memory fences until correctness is obtained, which is guaranteed
to happen. 

An advantage of our technique is that the underlying symbolic verification tool
makes a full exploration possible even for cyclic programs, which makes our
approach broadly applicable. The method has been tested with an experimental
implementation and can effectively handle a series of classical examples.Peer reviewe
DDIExtractor: A Web-based Java Tool for Extracting Drug-Drug Interactions from Biomedical Texts

Proceeding of: 16th International Conference on Applications of Natural Language to Information Systems, NLDB 201. Took place 2011, June 28-30, in Alicante, Spain. The event Web site is http://gplsi.dlsi.ua.es/congresos/nldb11/A drug-drug interaction (DDIs) occurs when one drug influences the level or activity of another drug. The detection of DDIs is an important research area in patient safety since these interactions can become very dangerous and increase health care costs. Although there are several databases and web tools providing information on DDIs to patients and health-care professionals, these resources are not comprehensive because many DDIs are only reported in the biomedical literature. This paper presents the first tool for detecting drug-drug interactions from biomedical texts called DDIExtractor. The tool allows users to search by keywords in the Medline 2010 baseline database and then detect drugs and DDIs in any retrieved document.This work is supported by the projects MA2VICMR
(S2009/TIC-1542) and MULTIMEDICA (TIN2010-20644-C03-01).Publicad
Evaluating EmotiBlog robustness for sentiment analysis tasks

EmotiBlog is a corpus labelled with the homonymous annotation schema designed for detecting subjectivity in the new textual genres. Preliminary research demonstrated its relevance as a Machine Learning resource to detect opinionated data. In this paper we compare EmotiBlog with the JRC corpus in order to check the EmotiBlog robustness of annotation. For this research we concentrate on its coarse-grained labels. We carry out a deep ML experimentation also with the inclusion of lexical resources. The results obtained show a similarity with the ones obtained with the JRC demonstrating the EmotiBlog validity as a resource for the SA task.This work has been partially founded by the TEXTMESS 2.0 (TIN2009-13391-C04-01) and Prometeo (PROMETEO/2009/199) projects and also by the complimentary action from the Generalitat valenciana (ACOMP/2011/001)
Design of a multiuser virtual trade fair using a game engine

The current world economic situation makes it necessary to develop new ways of establishing commercial relationships. One possible solution is to explore the advantages of virtual worlds, and for this reason online virtual trade fairs are becoming more popular in the business world. They enable companies to establish a trade relationship with their customers without the need to visit them in person. This is very attractive for exhibitors because it can save them money, which is a priority for many companies today. In this line, this article presents a multiuser virtual trade fair developed using 3D game engine technologys. Users represented by avatars can interact with each other while they are visiting the virtual fair, which has some interactive objects included in the stands to provide information about the exhibitors. This virtual world is accessible online, and visitors only require a plug-in on their computers to be able to enter the virtual world. The game technology makes it possible to obtain a high degree of realism: very real lighting, cast shadows, collision detection, etc. Moreover, the virtual world presented builds the 3D objects automatically. Participants in the trade fair can customize their virtual stand and the application will generate the code necessary for its inclusion in the rendered virtual world.This work was supported by the Spanish Ministry of Science and Technology project TIN2010-21089-C03-03. And also by Bancaja, project P1 1B2007-5