pinecone/core-2020-05-10-deduplication huggingface dataset:
Enabling vehicular data with distributed machine learning

This is a copy of the author 's final draft version of an article published in the journal Transactions on computational collective intelligence.\ud
The final publication is available at Springer via\ud
http://dx.doi.org/10.1007/978-3-662-49017-4_6Vehicular Data includes different facts and measurements made over a set of moving vehicles. Most of us use cars or public transportation for our work commute, daily routines and leisure. But, except of our destination, possible time of arrival and what is directly around us, we know very little about the traffic conditions in the city as a whole. Because all roads are connected in a vast network, events in other parts of town can and will directly affect us. The more we know about the traffic inside a city, the better decisions we can make. Vehicular measurements may contain a vast amount of information about the way our cities function. Information that can be used for more than improving our commute, it is indicative of other features of the city like the amount of pollution in different regions. All the information and knowledge we can extract, can be used to directly improve our life.\ud
We live in a world where data is constantly generated and we store it and process it at an ever growing rate. Vehicular Data does not stray from this fact and is rapidly growing in size and complexity, with more and more ways to monitoring traffic, either from inside cars or from sensors placed on the road. Smartphones and in-car-computers are now common and they can produce a vast amount of data: it can identify a cars location, destination, current speed and even driving habits.\ud
Machine learning is the perfect complement for Big Data, as large data sets can be rendered useless without methods to extract knowledge and information from them. Machine learning, currently a popular research topic, has a large number of algorithms design to achieve this task, of knowledge extraction. Most of these techniques and algorithms can be directly applied to Vehicular Data.\ud
In this article we demonstrate how the use of a simple algorithm, k-Nearest Neighbors, can be used to extract valuable information from even a relatively small vehicular data set. Because of the vast size of most of our cities and the number of cars that are on their roads at any time of the day, standard machine learning systems do not manage to process data in a manner that would permit real time use of the extracted information. A solution to this problem is brought by distributed systems and cloud processing. By parallelizing and distributing machine learning algorithms we can use data at its highest potential and with little delay. Here, we show how this can be achieved by distributing the k-Nearest Neighbors machine learning algorithm over MPI. We hope this would motivate the research into other combinations of merging machine learning algorithms with Vehicular Data sets.Peer ReviewedPostprint (author's final draft
Indistinguishability Obfuscation: From Approximate to Exact

We show general transformations from subexponentially-secure approximate indistinguishability obfuscation (IO) where the obfuscated circuit agrees with the original circuit on a 1/2+ϵ fraction of inputs on a certain samplable distribution, into exact indistinguishability obfuscation where the obfuscated circuit and the original circuit agree on all inputs. As a step towards our results, which is of independent interest, we also obtain an approximate-to-exact transformation for functional encryption. At the core of our techniques is a method for “fooling” the obfuscator into giving us the correct answer, while preserving the indistinguishability-based security. This is achieved based on various types of secure computation protocols that can be obtained from different standard assumptions.

Put together with the recent results of Canetti, Kalai and Paneth (TCC 2015), Pass and Shelat (TCC 2016), and Mahmoody, Mohammed and Nemathaji (TCC 2016), we show how to convert indistinguishability obfuscation schemes in various ideal models into exact obfuscation schemes in the plain model.National Science Foundation (U.S.) (Grant CNS-1350619)National Science Foundation (U.S.) (Grant CNS-1414119
A Method for Invariant Generation for Polynomial Continuous Systems

International audienceThis paper presents a method for generating semi-algebraic invariants for systems governed by non-linear polynomial ordinary differential equations under semi-algebraic evolution constraints. Based on the notion of discrete abstraction , our method eliminates unsoundness and unnecessary coarseness found in existing approaches for computing abstractions for non-linear continuous systems and is able to construct invariants with intricate boolean structure, in contrast to invariants typically generated using template-based methods. In order to tackle the state explosion problem associated with discrete abstraction, we present invariant generation algorithms that exploit sound proof rules for safety verification , such as differential cut (DC), and a new proof rule that we call differential divide-and-conquer (DDC), which splits the verification problem into smaller sub-problems. The resulting invariant generation method is observed to be much more scalable and efficient than the na¨ıvena¨ıve approach, exhibiting orders of magnitude performance improvement on many of the problems
Tight Cutoffs for Guarded Protocols with Fairness

Guarded protocols were introduced in a seminal paper by Emerson and Kahlon
(2000), and describe systems of processes whose transitions are enabled or
disabled depending on the existence of other processes in certain local states.
We study parameterized model checking and synthesis of guarded protocols, both
aiming at formal correctness arguments for systems with any number of
processes. Cutoff results reduce reasoning about systems with an arbitrary
number of processes to systems of a determined, fixed size. Our work stems from
the observation that existing cutoff results for guarded protocols i) are
restricted to closed systems, and ii) are of limited use for liveness
properties because reductions do not preserve fairness. We close these gaps and
obtain new cutoff results for open systems with liveness properties under
fairness assumptions. Furthermore, we obtain cutoffs for the detection of
global and local deadlocks, which are of paramount importance in synthesis.
Finally, we prove tightness or asymptotic tightness for the new cutoffs.Comment: Accepted for publication at VMCAI 2016. Extended version, revised
  after conference review
Program Analysis with Local Policy Iteration

We present a new algorithm for deriving numerical invariants that combines
the precision of max-policy iteration with the flexibility and scalability of
conventional Kleene iterations. It is defined in the Configurable Program
Analysis (CPA) framework, thus allowing inter-analysis communication.
  It uses adjustable-block encoding in order to traverse loop-free program
sections, possibly containing branching, without introducing extra abstraction.
Our technique operates over any template linear constraint domain, including
the interval and octagon domains; templates can also be derived from the
program source.
  The implementation is evaluated on a set of benchmarks from the Software
Verification Competition (SV-Comp). It competes favorably with state-of-the-art
analyzers
A Community-Built Virtual Heritage Collection

The HeritageTogether project has developed a web platform through which members of the public can upload their own photographs of heritage assets to be processed into 3D models using an automated Structure-from-Motion work flow. The web platform is part of a larger project which aims to capture, create and archive digital heritage assets in conjunction with local communities in Wales, UK, with a focus on megalithic monuments. The 3D models are displayed online using a lightbox style gallery and a virtual museum, while the large amounts of additional data produced are stored in an online archive. Each representation provides a different perspective and context to the data, allowing users to explore the data in a multitude of ways. HeritageTogether is a digital community and community-built archive and museum of heritage data, developed to inspire local communities to learn more about their heritage and to help to preserve it
Hierarchy of Groups Evaluation Using Different F-score Variants

The paper presents a cursory examination of clustering, focusing on a rarely
explored field of hierarchy of clusters. Based on this, a short discussion of
clustering quality measures is presented and the F-score measure is examined
more deeply. As there are no attempts to assess the quality for hierarchies of
clusters, three variants of the F-Score based index are presented: classic,
hierarchical and partial order. The partial order index is the authors'
approach to the subject. Conducted experiments show the properties of the
considered measures. In conclusions, the strong and weak sides of each variant
are presented.Comment: Presented on ACIIDS2016 conference https://aciids.pwr.edu.pl/. The
  final publication is available at Springer via
  http://dx.doi.org/10.1007/978-3-662-49381-6_6
Ensuring the Correctness of Business Workflows at the Syntactic Level: An Ontological Approach

International audienceHigh quality business workflow definitions play an important role in the organization. An incorrectly defined workflow may lead to unexpected results. Therefore, each business workflow definition should be carefully analyzed before it is put into use. In this paper, we propose an ontological approach which is suitable for ensuring the syntactic correct-ness of business workflows. In details, to represent CPNs with OWL DL, we first introduce the CPN Ontology. Then, we define axioms, which are added to the CPN Ontology to provide automated support for establishing the correctness of business workflows. Finally, by relying on the CORESE semantic engine, SPARQL queries are implemented to detect shortcomings in concrete workflows. To the best of our knowledge, this is a novel approach for the representation and verification of business workflows based on ontologies
Needle & knot : binder boilerplate tied up

To lighten the burden of programming language mechanization, many approaches have been developed that tackle the substantial boilerplate which arises from variable binders. Unfortunately, the existing approaches are limited in scope. They typically do not support complex binding forms (such as multi-binders) that arise in more advanced languages, or they do not tackle the boilerplate due to mentioning variables and binders in relations. As a consequence, the human mechanizer is still unnecessarily burdened with binder boilerplate and discouraged from taking on richer languages. 
This paper presents Knot, a new approach that substantially extends the support for binder boilerplate. Knot is a highly expressive language for natural and concise specification of syntax with binders. Its meta-theory constructively guarantees the coverage of a considerable amount of binder boilerplate for well-formed specifications, including that for well-scoping of terms and context lookups. Knot also comes with a code generator, Needle, that specializes the generic boilerplate for convenient embedding in COQ and provides a tactic library for automatically discharging proof obligations that frequently come up in proofs of weakening and substitution lemmas of type-systems. 
Our evaluation shows, that Needle & Knot significantly reduce the size of language mechanizations (by 40% in our case study). Moreover, as far as we know, Knot enables the most concise mechanization of the POPLmark Challenge (1a + 2a) and is two-thirds the size of the next smallest. Finally, Knot allows us to mechanize for instance dependentlytyped languages, which is notoriously challenging because of dependent contexts and mutually-recursive sorts with variables
On the Relative Expressiveness of Higher-Order Session Processes

© Springer-Verlag Berlin Heidelberg 2016.By integrating constructs from the λ-calculus and the π-calculus, in higher-order process calculi exchanged values may contain processes. This paper studies the relative expressiveness of HOπ, the higher-order π-calculus in which communications are governed by session types. Our main discovery is that HO, a subcalculus of HOπ which lacks name-passing and recursion, can serve as a new core calculus for session-typed higher-order concurrency. By exploring a new bisimulation for HO, we show that HO can encode HOπ fully abstractly (up to typed contextual equivalence) more precisely and efficiently than the first-order session π-calculus (π). Overall, under session types, HOπ, HO, and π are equally expressive; however, HOπ and HO are more tightly related than HOπ and π
A Timed Process Algebra for Wireless Networks

This paper proposes a timed process algebra for wireless networks, an
extension of the Algebra for Wireless Networks. It combines treatments of local
broadcast, conditional unicast and data structures, which are essential
features for the modelling of network protocols. In this framework we model and
analyse the Ad hoc On-Demand Distance Vector routing protocol, and show that,
contrary to claims in the literature, it fails to be loop free. We also present
boundary conditions for a fix ensuring that the resulting protocol is indeed
loop free.Comment: An extended abstract of this paper---everything but the
  appendices---appeared in Proc. ESOP'16. arXiv admin note: text overlap with
  arXiv:1312.764
On Hierarchical Communication Topologies in the pi-calculus

This paper is concerned with the shape invariants satisfied by the
communication topology of {\pi}-terms, and the automatic inference of these
invariants. A {\pi}-term P is hierarchical if there is a finite forest T such
that the communication topology of every term reachable from P satisfies a
T-shaped invariant. We design a static analysis to prove a term hierarchical by
means of a novel type system that enjoys decidable inference. The soundness
proof of the type system employs a non-standard view of {\pi}-calculus
reactions. The coverability problem for hierarchical terms is decidable. This
is proved by showing that every hierarchical term is depth-bounded, an
undecidable property known in the literature. We thus obtain an expressive
static fragment of the {\pi}-calculus with decidable safety verification
problems.Comment: 42 pages, ESOP16. arXiv admin note: text overlap with
  arXiv:1502.0094
Modular termination verification for non-blocking concurrency

© Springer-Verlag Berlin Heidelberg 2016.We present Total-TaDA, a program logic for verifying the total correctness of concurrent programs: that such programs both terminate and produce the correct result. With Total-TaDA, we can specify constraints on a thread’s concurrent environment that are necessary to guarantee termination. This allows us to verify total correctness for nonblocking algorithms, e.g. a counter and a stack. Our specifications can express lock- and wait-freedom. More generally, they can express that one operation cannot impede the progress of another, a new non-blocking property we call non-impedance. Moreover, our approach is modular. We can verify the operations of a module independently, and build up modules on top of each other
The I/O Complexity of Computing Prime Tables

International audienceWe revisit classical sieves for computing primes and analyze their performance in the external-memory model. Most prior sieves are analyzed in the RAM model, where the focus is on minimizing both the total number of operations and the size of the working set. The hope is that if the working set fits in RAM, then the sieve will have good I/O performance, though such an outcome is by no means guaranteed by a small working-set size. We analyze our algorithms directly in terms of I/Os and operations. In the external-memory model, permutation can be the most expensive aspect of sieving, in contrast to the RAM model, where permutations are trivial. We show how to implement classical sieves so that they have both good I/O performance and good RAM performance, even when the problem size N becomes huge—even superpolynomially larger than RAM. Towards this goal, we give two I/O-efficient priority queues that are optimized for the operations incurred by these sieves
Unshuffling Permutations

International audienceA permutation is said to be a square if it can be obtained by shuffling two order-isomorphic patterns. The definition is intended to be the natural counterpart to the ordinary shuffle of words and languages. In this paper, we tackle the problem of recognizing square permutations from both the point of view of algebra and algorithms. On the one hand, we present some algebraic and combinatorial properties of the shuffle product of permutations. We follow an unusual line consisting in defining the shuffle of permutations by means of an unshuffling operator, known as a coproduct. This strategy allows to obtain easy proofs for algebraic and combinatorial properties of our shuffle product. We besides exhibit a bijection between square (213, 231)-avoiding permutations and square binary words. On the other hand, by using a pattern avoidance criterion on oriented perfect matchings, we prove that recognizing square permutations is NP-complete
Light Scattering and Thermal Emission by Primitive Dust Particles in
  Planetary Systems

This review focuses on numerical approaches to deducing the light-scattering
and thermal-emission properties of primitive dust particles in planetary
systems from astronomical observations. The particles are agglomerates of small
grains with sizes comparable to visible wavelength and compositions being
mainly magnesium-rich silicates, iron-bearing metals, and organic refractory
materials in pristine phases. These unique characteristics of primitive dust
particles reflect their formation and evolution around main-sequence stars of
essentially solar composition. The development of light-scattering theories has
been offering powerful tools to make a thorough investigation of light
scattering and thermal emission by primitive dust agglomerates in such a
circumstellar environment. In particular, the discrete dipole approximation,
the T-matrix method, and effective medium approximations are the most popular
techniques for practical use in astronomy. Numerical simulations of light
scattering and thermal emission by dust agglomerates of submicrometer-sized
constituent grains have a great potential to provide new state-of-the-art
knowledge of primitive dust particles in planetary systems. What is essential
to this end is to combine the simulations with comprehensive collections of
relevant results from not only astronomical observations, but also in-situ data
analyses, laboratory sample analyses, laboratory analogue experiments, and
theoretical studies on the origin and evolution of the particles.Comment: 61 pages, 23 figures, to appear in Light Scattering Reviews, Volume
  11 (Springer, ISBN: 978-3-662-49536-0
Comprehensive parametric polymorphism : categorical models and type theory

This paper combines reflexive-graph-category structure for relational parametricity with fibrational models of impredicative polymorphism. To achieve this, we modify the definition of fibrational model of impredicative polymorphism by adding one further ingredient to the structure: comprehension in the sense of Lawvere. Our main result is that such comprehensive models, once further endowed with reflexive-graph-category structure, enjoy the expected consequences of parametricity. This is proved using a type-theoretic presentation of the category-theoretic structure, within which the desired consequences of parametricity are derived. The formalisation requires new techniques because equality relations are not available, and standard arguments that exploit equality need to be reworked
Game semantics for bounded polymorphism

We describe a denotational, intensional semantics for programs with polymorphic types with bounded quantification, in which phenomena such as inheritance between stateful objects may be represented and studied. Our model is developed from a game semantics for unbounded polymorphism, by establishing dinaturality properties of generic strategies, and using them to give a new construction for interpreting subtyping constraints and bounded quantification. We use this construction to give a denotational semantics for a programming language with general references and an expressive polymorphic typing system. We show that full abstraction fails in general in this model, but that it holds for all terms at a rich collection of bounded types
A theory of monitors

We develop a behavioural theory for monitors — software entities that passively analyse the runtime behaviour of systems so as to infer properties about them. First, we extend the monitor language and instrumentation relation of [17] to handle piCalculus process monitoring. We then identify contextual behavioural preorders that allow us to re-late monitors according to criteria defined over monitored executions of piCalculus processes. Subsequently, we develop alternative monitor pre-orders that are more tractable, and prove full-abstraction for the latter alternative preorders with respect to the contextual preorders.peer-reviewe
Hybrid Session Verification through Endpoint API Generation

© Springer-Verlag Berlin Heidelberg 2016.This paper proposes a new hybrid session verification methodology for applying session types directly to mainstream languages, based on generating protocol-specific endpoint APIs from multiparty session types. The API generation promotes static type checking of the behavioural aspect of the source protocol by mapping the state space of an endpoint in the protocol to a family of channel types in the target language. This is supplemented by very light run-time checks in the generated API that enforce a linear usage discipline on instances of the channel types. The resulting hybrid verification guarantees the absence of protocol violation errors during the execution of the session. We implement our methodology for Java as an extension to the Scribble framework, and use it to specify and implement compliant clients and servers for real-world protocols such as HTTP and SMTP
A Graph-Based Semantics Workbench for Concurrent Asynchronous Programs

A number of novel programming languages and libraries have been proposed that
offer simpler-to-use models of concurrency than threads. It is challenging,
however, to devise execution models that successfully realise their
abstractions without forfeiting performance or introducing unintended
behaviours. This is exemplified by SCOOP---a concurrent object-oriented
message-passing language---which has seen multiple semantics proposed and
implemented over its evolution. We propose a "semantics workbench" with fully
and semi-automatic tools for SCOOP, that can be used to analyse and compare
programs with respect to different execution models. We demonstrate its use in
checking the consistency of semantics by applying it to a set of representative
programs, and highlighting a deadlock-related discrepancy between the principal
execution models of the language. Our workbench is based on a modular and
parameterisable graph transformation semantics implemented in the GROOVE tool.
We discuss how graph transformations are leveraged to atomically model
intricate language abstractions, and how the visual yet algebraic nature of the
model can be used to ascertain soundness.Comment: Accepted for publication in the proceedings of FASE 2016 (to appear