pinecone/core-2020-05-10-deduplication huggingface dataset:
Validation of the HADRIAN system using an ATM evaluation case study

This is a conference paper. The original publication is available at www.springerlink.comThe HADRIAN human modelling system is under development as part of the EPSRC funded AUNT-SUE project. The HADRIAN system aims to foster a ‘design for all’ ethos by allowing ergonomists and designers to see the effects of different kinds of disability on the physical capabilities of elderly and disabled people. This system is based upon the long established SAMMIE system, and uses data collected from 102 people, 79 of whom are registered as disabled, or have age related mobility issues. The HADRIAN system allows three dimensional CAD data of new products to be imported, with a subsequent automated analysis using all of the 102 sample members. The following paper describes the process and results gathered from a validation study using an ATM design as a case study. The results indicated that fine tuning of the behavioural data built into HADRIAN would improve the accuracy of an automated product analysis
Adapting the presentation layer in rich Internet applications

Rich Internet Applications offer Web surfers a richer user experience, mainly due to better responsiveness and enhanced user interface capabilities. In recent years, existing design methodologies targeting traditional Web 1.0 applications were extended to also support RIAs. These extensions do not yet cover all design concerns typically encountered in state-of-the-art Web applications. One yet unsupported aspect is the personalization of content and presentation to the specific user and his/her context, exploiting the extra capabilities offered by RIAs. This article addresses this hiatus and presents an extension of the OOH4RIA approach to include presentation personalization support, focusing on Rich Internet Applications.This work has been co-supported by the ESPIA project (TIN2007-67078) from the Spanish Ministry of Education and Science and the DEMETER (GVPRE/2008/063) project from the Valencia Ministry of Enterprise, University and Science (Spain)
A new approach to non-termination analysis of Logic Programs

In this paper, we present a new approach to non-termination analysis of logic programs, based on moded SLDNF-resolution. Moded SLDNF-resolution is a symbolic execution for moded goals, developed for termination prediction. To prove non-termination, we use a complete loop checker to create a finite symbolic derivation tree of a logic program for a moded query. Then, we check if this derivation tree contains an infinite loop, using a new non-termination condition. We implemented this approach and tested it on the benchmark from the Termination Competition of 2007. The results are very satisfactory: our tool is able to prove non-termination and construct non-terminating queries for all non-terminating benchmark programs, and thus, significantly improves on the results of the only other non-termination analyzer, NTI.status: publishe
Debugging for model expansion

Due to the development of efficient solvers, declarative problem solving frameworks based on model generation are becoming more and more applicable in practice. However, there are almost no tools to support debugging in these frameworks. For several reasons, current solvers are not suitable for debugging by tracing. In this paper, we propose a new solver algorithm for one of these frameworks, namely Model Expansion, that allows for debugging by tracing. We explain how to explore the trace of this solver in order to quickly locate a bug and we compare our debugging method with existing ones for Answer Set Programming and the Alloy system.status: publishe
Attributed data for CHR indexing

The overhead of matching CHR rules is alleviated by constraint store indexing. Attributed variables provide an efficient means of indexing on logical variables. Existing indexing strategies for ground terms, based on hash tables, incur considerable performance overhead, especially when frequently computing hash values for large terms.
In this paper we (1) propose attributed data, a new data representation for ground terms inspired by attributed variables, that avoids the overhead of hash-table indexing, (2) describe program analysis and transformation techniques that make attributed data more effective, and (3) provide experimental results that establish the usefulness of our approach.status: publishe
Proving termination by invariance relations

We propose a new constraint-based approach to termination analysis, applicable to Logic Programming (LP) and Constraint Handling Rules (CHR). Our approach further extends the existing constraint-based approaches for LP based on polynomial interpretations and introduces a whole new level of expressivity. We can handle problems such as bounded increase and integer arithmetic, elegantly. Furthermore, we are able to prove termination of programs that only terminate for subsets of the considered queries. Examples are algorithms that manipulate graphs and that only terminate if the graph in the input is cycle-free. This information cannot be represented, using the existing techniques in termination analysis. Therefore, we introduce invariance relations, representing relations among terms that hold on atoms during calls to the program. These relations can also be derived in a constraint-based manner and they can be used as a basis for a more expressive interpretation of the atoms of the program. We discuss our technique in the context of CHR, solving an important class of open problems containing transitivity rules. We also demonstrate the technique in an LP context and show that it is more powerful than existing constraint-based approaches.status: publishe
Automating termination proofs for CHR

We propose a constraint-based approach towards automated termination analysis of Constraint Handling Rules (CHR). Similar to such approaches for Logic Programming (LP), we define a symbolic level mapping on atoms of the program and express termination conditions using these. Then, we search for an assignment to the symbolic coefficients, validating the termination conditions. However, different from the approaches developed for LP, termination of CHR programs is concerned with multi-headed rules, while the existing constraint-based approaches in LP are developed for definite programs. These cannot be adapted directly to a multi-headed context. In the following we discuss a constraint-based approach for CHR programs and show how such an approach can be obtained by an elegant reuse of existing techniques in LP. We evaluate the approach, using our implementation, CHRisTA.status: publishe
Research summary: Termination of CHR

Constraint Handling Rules (CHR) is a high-level programming language, designed for the easy implementation of custom constraint solvers. CHR is a language-extension, built on top of Java, C and half a dozen Prolog-variants. The language is currently used in many projects.

In contrast to earlier approaches, CHR has a ''no box''-approach and thus can implement any sort of solvers. Of course this affects the efficiency of the obtained solver. In order to obtain the same level of efficiency, we need analysis tools to detect the properties of a CHR program that lead to optimizations.

In CHR, termination is one of the most important properties of a program. Other important properties, such as confluence can be decided given termination. But also for the programmer this is an important property. CHR is a multi-headed language in which loops are often much more difficult to detect than in single-headed languages such as Prolog.status: publishe
Phase III of USO Solar Vector Magnetograph

The Solar Vector Magnetograph (SVM) is a modern imaging spectropolarimeter
installed at Udaipur Solar Observatory (USO). Earlier phases saw the
development of the instrument using off-the-shelf components with in-house
software development. Subsequently, improvements were done in the
opto-mechanical design of the sub-systems and the telescope tracking system.
The third phase of the instrument development saw three major improvements,
these include: (i) installation of a web-camera based telescope guiding system,
developed in-house, (ii) high-cadence spectropolarimetry using Liquid Crystal
Variable Retarders and a fast CCD camera and (iii)inclusion of Na D1 line with
regular photospheric Fe 630.2 nm line for chromospheric observations.Comment: 3 pages, 1 table; To appear in the Proceedings of Evershed Meeting,
  IIA, Bangalor
Vainu Bappu Memorial Lecture: What is a sunspot?

Sunspots have been known in the West since Galileo Galilei and Thomas Harriot
first used telescopes to observe the Sun nearly four centuries ago; they have
been known to the Chinese for more than two thousand years. They appear as
relatively dark patches on the surface of the Sun, and are caused by
concentrations of magnetism which impede the flow of heat from deep inside the
Sun up to its othewise brilliant surface. The spots are not permanent: the
total number of spots on the Sun varies cyclically in time, with a period of
about eleven years, associated with which there appear to be variations in our
climate. When there are many spots, it is more dangerous for spacecraft to
operate. The cause of the spots is not well understood; nor is it known for
sure how they die. Their structure beneath the surface of the Sun is in some
dispute, although much is known about their properties at the surface,
including an outward material flow which was discovered by John Evershed
observing the Sun from Kodaikanal a hundred years ago. I shall give you a
glimpse of how we are striving to deepen our understanding of these fascinating
features, and of some of the phenomena that appear to be associated with them.Comment: Lecture delivered at the Indian Institute of Astrophysics, December
  2008 Typing errors corrected To appear in Magnetic Coupling between the
  Interior and the Atmosphere of the Sun, ed. S.S. Hasan & R.J. Rutten, Astr.
  Sp. Sci. Pro
The Waldmeier Effect in Sunspot Cycles

We discuss two aspects of the Waldmeier Effect, namely (1) the rise times of
sunspot cycles are anti-correlated to their strengths (WE1) and (2) the rates
of rise of the cycles are correlated to their strengths (WE2). From analysis of
four different data sets we conclude that both WE1 and WE2 exist in all the
data sets. We study these effects theoretically by introducing suitable
stochastic fluctuations in our regular solar dynamo model.Comment: Magnetic Coupling between the Interior and Atmosphere of the Sun;
  Astrophysics and Space Science Proceeding
Outstanding Issues in Solar Dynamo Theory

The magnetic activity of the Sun, as manifested in the sunspot cycle,
originates deep within its convection zone through a dynamo mechanism which
involves non-trivial interactions between the plasma and magnetic field in the
solar interior. Recent advances in magnetohydrodynamic dynamo theory have led
us closer towards a better understanding of the physics of the solar magnetic
cycle. In conjunction, helioseismic observations of large-scale flows in the
solar interior has now made it possible to constrain some of the parameters
used in models of the solar cycle. In the first part of this review, I briefly
describe this current state of understanding of the solar cycle. In the second
part, I highlight some of the outstanding issues in solar dynamo theory related
to the the nature of the dynamo $\alpha$-effect, magnetic buoyancy and the
origin of Maunder-like minima in activity. I also discuss how poor constraints
on key physical processes such as turbulent diffusion, meridional circulation
and turbulent flux pumping confuse the relative roles of these vis-a-vis
magnetic flux transport. I argue that unless some of these issues are
addressed, no model of the solar cycle can claim to be ``the standard model'',
nor can any predictions from such models be trusted; in other words, we are
still not there yet.Comment: To appear in "Magnetic Coupling between the Interior and the
  Atmosphere of the Sun", eds. S.S. Hasan and R.J. Rutten, Astrophysics and
  Space Science Proceedings, Springer-Verlag, Heidelberg, Berlin, 200
Covariant Mappings for the Description of Measurement, Dissipation and
  Decoherence in Quantum Mechanics

The general formalism of quantum mechanics for the description of statistical
experiments is briefly reviewed, introducing in particular position and
momentum observables as POVM characterized by their covariance properties with
respect to the isochronous Galilei group. Mappings describing state
transformations both as a consequence of measurement and of dynamical evolution
for a closed or open system are considered with respect to the general
constraints they have to obey and their covariance properties with respect to
symmetry groups. In particular different master equations are analyzed in view
of the related symmetry group, recalling the general structure of mappings
covariant under the same group. This is done for damped harmonic oscillator,
two-level system and quantum Brownian motion. Special attention is devoted to
the general structure of translation-covariant master equations. Within this
framework a recently obtained quantum counterpart of the classical linear
Boltzmann equation is considered, as well as a general theoretical framework
for the description of different decoherence experiments, pointing to a
connection between different possible behaviours in the description of
decoherence and the characteristic functions of classical L\'evy processes.Comment: Comments: 38 pages, to appear in Lecture Notes in Physics,
  Springer-Verla
On Finding Small 2-Generating Sets

International audienceGiven a set of positive integers S, we consider the problem of finding a minimum cardinality set of positive integers X (called a minimum 2-generating set of S) s.t. every element of S is an element of X or is the sum of two (non-necessarily distinct) elements of X. We give elementary properties of 2-generating sets and prove that finding a minimum cardinality 2-generating set is hard to approximate within ratio 1 + epsilon for any epsilon > 0. We then prove our main result, which consists in a representation lemma for minimum cardinality 2-generating sets
Observer design for systems with non small and unknown time-varying delay

International audienceThis chapter deals with the design of observers for linear systems with unknown, time-varying, but bounded delays (on the state and on the input). In this work, the problem is solved for a class of systems by combining the unknown input observer approach with an adequate choice of a Lyapunov-Krasovskii functional for non small delay systems. This result provides workable conditions in terms of rank assumptions and LMI conditions. The dynamic properties of the observer are also analyzed. A 4th-order example is used to demonstrate the feasibility of the proposed solution
Node-weighted Steiner tree and group Steiner tree in planar graphs

We improve the approximation ratios for two optimization problems in planar graphs. For node-weighted Steiner tree, a classical network-optimization problem, the best achievable approximation ratio in general graphs is Θ [theta] (logn), and nothing better was previously known for planar graphs. We give a constant-factor approximation for planar graphs. Our algorithm generalizes to allow as input any nontrivial minor-closed graph family, and also generalizes to address other optimization problems such as Steiner forest, prize-collecting Steiner tree, and network-formation games.
The second problem we address is group Steiner tree: given a graph with edge weights and a collection of groups (subsets of nodes), find a minimum-weight connected subgraph that includes at least one node from each group. The best approximation ratio known in general graphs is O(log3 [superscript 3]  n), or O(log2 [superscript 2] n) when the host graph is a tree. We obtain an O(log n polyloglog n) approximation algorithm for the special case where the graph is planar embedded and each group is the set of nodes on a face. We obtain the same approximation ratio for the minimum-weight tour that must visit each group
General Scheme for Perfect Quantum Network Coding with Free Classical
  Communication

This paper considers the problem of efficiently transmitting quantum states
through a network. It has been known for some time that without additional
assumptions it is impossible to achieve this task perfectly in general --
indeed, it is impossible even for the simple butterfly network. As additional
resource we allow free classical communication between any pair of network
nodes. It is shown that perfect quantum network coding is achievable in this
model whenever classical network coding is possible over the same network when
replacing all quantum capacities by classical capacities. More precisely, it is
proved that perfect quantum network coding using free classical communication
is possible over a network with $k$ source-target pairs if there exists a
classical linear (or even vector linear) coding scheme over a finite ring. Our
proof is constructive in that we give explicit quantum coding operations for
each network node. This paper also gives an upper bound on the number of
classical communication required in terms of $k$, the maximal fan-in of any
network node, and the size of the network.Comment: 12 pages, 2 figures, generalizes some of the results in
  arXiv:0902.1299 to the k-pair problem and codes over rings. Appeared in the
  Proceedings of the 36th International Colloquium on Automata, Languages and
  Programming (ICALP'09), LNCS 5555, pp. 622-633, 200
An explicit formula for the free exponential modality of linear logic

International audienceThe exponential modality of linear logic associates a commutative comonoid !A to every formula A in order to duplicate it. Here, we explain how to compute the free commutative comonoid !A as a sequential limit of equalizers in any symmetric monoidal category where this sequential limit exists and commutes with the tensor product. We then apply this general recipe to two familiar models of linear logic, based on coherence spaces and on Conway games. This algebraic approach enables to unify for the rst time apparently different constructions of the exponential modality in spaces and games. It also sheds light on the subtle duplication policy of linear logic. On the other hand, we explain at the end of the article why the formula does not work in the case of the niteness space model
Rate-Based Transition Systems for Stochastic Process Calculi

A variant of Rate Transition Systems (RTS), proposed by Klin and Sassone, is introduced and used as the basic model for defining stochastic behaviour of processes. The transition relation used in our variant associates to each process, for each action, the set of possible futures paired with a measure indicating their rates. We show how RTS can be used for providing the operational semantics of stochastic extensions of classical formalisms, namely CSP and CCS. We also show that our semantics for stochastic CCS guarantees associativity of parallel composition. Similarly, in contrast with the original definition by Priami, we argue that a semantics for stochastic π-calculus can be provided that guarantees associativity of parallel composition
On Observing Dynamic Prioritised Actions in SOC

We study the impact on observational semantics for SOC of priority mechanisms which combine dynamic priority with local pre-emption. We define manageable notions of strong and weak labelled bisimilarities for COWS, a process calculus for SOC, and provide alternative characterisations in terms of open barbed bisimilarities. These semantics show that COWS’s priority mechanisms partially recover the capability to observe receive actions (that could not be observed in a purely asynchronous setting) and that high priority primitives for termination impose specific conditions on the bisimilarities
Integrated Reasoning and Proof Choice Point Selection in the Jahob System – Mechanisms for Program Survival

In recent years researchers have developed a wide range of powerful automated reasoning systems. We have leveraged these systems to build Jahob, a program specification, analysis, and verification system. In contrast to many such systems, which use a monolithic reasoning approach, Jahob provides a general integrated reasoning framework, which enables multiple automated reasoning systems to work together to prove the desired program correctness properties.
We have used Jahob to prove the full functional correctness of a collection of linked data structure implementations. The automated reasoning systems are able to automatically perform the vast majority of the reasoning steps required for this verification. But there are some complex verification conditions that they fail to prove. We have therefore developed a proof language, integrated into the underlying imperative Java programming language, that developers can use to control key choice points in the proof search space. Once the developer has resolved these choice points, the automated reasoning systems are able to complete the verification. This approach appropriately leverages both the developer’s insight into the high-level structure of the proof and the ability of the automated reasoning systems to perform the mechanical steps required to prove the verification conditions.
Building on Jahob’s success with this challenging program verification problem, we contemplate the possibility of verifying the complete absence of fatal errors in large software systems. We envision combining simple techniques that analyze the vast majority of the program with heavyweight techniques that analyze those more sophisticated parts of the program that may require arbitrarily sophisticated reasoning. Modularity mechanisms such as abstract data types enable the sound division of the program for this purpose. The goal is not a completely correct program, but a program that can survive any remaining errors to continue to provide acceptable service
Tag based collaborative filtering for recommender\ud
systems

Collaborative tagging can help users organize, share and retrieve information\ud
in an easy and quick way. For the collaborative tagging information\ud
implies user’s important personal preference information, it can be used to recommend\ud
personalized items to users. This paper proposes a novel tag-based\ud
collaborative filtering approach for recommending personalized items to users\ud
of online communities that are equipped with tagging facilities. Based on the\ud
distinctive three dimensional relationships among users, tags and items, a new\ud
similarity measure method is proposed to generate the neighborhood of users\ud
with similar tagging behavior instead of similar implicit ratings. The promising\ud
experiment result shows that by using the tagging information the proposed approach\ud
outperforms the standard user and item based collaborative filtering\ud
approaches
Semantic trajectory compression

In the light of rapidly growing repositories capturing the \ud
movement tra jectories of people in spacetime, the need for tra jectory compression becomes obvious. This paper argues for semantic trajectory compression (STC) as a means of substantially compressing the movement trajectories in an urban environment with acceptable information loss. STC exploits that human urban movement and its large–scale use \ud
(LBS, navigation) is embedded in some geographic context, typically deﬁned by transportation networks. STC achieves its compression rate by replacing raw, highly redundant position information from, for example, GPS sensors with a semantic representation of the tra jectory consisting \ud
of a sequence of events. The paper explains the underlying principles of STC and presents an example use case