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See detailExtended Ensembles Techniques
Schilling, Tanja UL

Presentation (2008)

Detailed reference viewed: 9 (0 UL)
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See detailExtended Explanatory Argumentation Frameworks
Dauphin, Jérémie UL; Cramer, Marcos UL

in Theory and Applications of Formal Argumentation (2018)

Multiple extensions of Dung's argumentation frameworks (AFs) have been proposed in order to model features of argumentation that cannot be directly modeled in AFs. One technique that has already ... [more ▼]

Multiple extensions of Dung's argumentation frameworks (AFs) have been proposed in order to model features of argumentation that cannot be directly modeled in AFs. One technique that has already previously proven useful to study and combine such extensions is the meta-argumentation methodology involving the notion of a flattening. In order to faithfully model the interaction between explanation argumentation in scientific debates, Šešelja and Straßer have introduced Explanatory Argumentation Frameworks (EAFs). In this paper, we first prove that the flattening technique works as expected for recursive (higher-order) attacks. Then we apply this technique in order to combine EAFs with multiple other extensions that have been proposed to AFs, namely with recursive attacks, joint attacks and a support relation between arguments. This gives rise to Extended Explanatory Argumentation Frameworks (EEAFs). We illustrate the applicability of EEAFs by using them to model a piece of argumentation from a research-level philosophy book. [less ▲]

Detailed reference viewed: 200 (16 UL)
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See detailAn extended finite element library
Bordas, Stéphane UL; Nguyen, P. V.; Dunant, C. et al

in International Journal for Numerical Methods in Engineering (2007), 71(6), 703-732

This paper presents and exercises a general structure for an object-oriented-enriched finite element code. The programming environment provides a robust tool for extended finite element (XFEM ... [more ▼]

This paper presents and exercises a general structure for an object-oriented-enriched finite element code. The programming environment provides a robust tool for extended finite element (XFEM) computations and a modular and extensible system. The programme structure has been designed to meet all natural requirements for modularity, extensibility, and robustness. To facilitate mesh-geometry interactions with hundreds of enrichment items, a mesh generator and mesh database are included. The salient features of the programme are: flexibility in the integration schemes (subtriangles, subquadrilaterals, independent near-tip, and discontinuous quadrature rules); domain integral methods for homogeneous and bi-material interface cracks arbitrarily oriented with respect to the mesh; geometry is described and updated by level sets, vector level sets or a standard method; standard and enriched approximations are independent; enrichment detection schemes: topological, geometrical, narrow-band, etc.; multi-material problem with an arbitrary number of interfaces and slip-interfaces; non-linear material models such as J2 plasticity with linear, isotropic and kinematic hardening. To illustrate the possible applications of our paradigm, we present 2D linear elastic fracture mechanics for hundreds of cracks with local near-tip refinement, and crack propagation in two dimensions as well as complex 3D industrial problems. Copyright © 2007 John Wiley & Sons, Ltd. [less ▲]

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See detailExtended Finite Element Method
Fries, T.-P.; Zilian, Andreas UL; Moës, N.

in International Journal for Numerical Methods in Engineering (2011), 86(4-5), 403

[No abstract available]

Detailed reference viewed: 80 (3 UL)
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See detailAn extended finite element method (XFEM) for linear elastic fracture with smooth nodal stress
Peng, Xuan; Kulasegaram, Sivakumar; Bordas, Stéphane UL et al

in Engineering Fracture Mechanics (2014)

Detailed reference viewed: 454 (4 UL)
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See detailExtended finite element method for dynamic fracture of piezo-electric materials
Nguyen-Vinh, H.; Bakar, I.; Msekh, M. A. et al

in Engineering Fracture Mechanics (2012), 92

We present an extended finite element formulation for dynamic fracture of piezo-electric materials. The method is developed in the context of linear elastic fracture mechanics. It is applied to mode I and ... [more ▼]

We present an extended finite element formulation for dynamic fracture of piezo-electric materials. The method is developed in the context of linear elastic fracture mechanics. It is applied to mode I and mixed mode-fracture for quasi-steady cracks. An implicit time integration scheme is exploited. The results are compared to results obtained with the boundary element method and show excellent agreement. [less ▲]

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See detailExtended finite element method with edge-based strain smoothing (ESm-XFEM) for linear elastic crack growth
Chen, L.; Rabczuk, T.; Bordas, Stéphane UL et al

in Computer Methods in Applied Mechanics & Engineering (2012), 209-212

This paper presents a strain smoothing procedure for the extended finite element method (XFEM). The resulting "edge-based" smoothed extended finite element method (ESm-XFEM) is tailored to linear elastic ... [more ▼]

This paper presents a strain smoothing procedure for the extended finite element method (XFEM). The resulting "edge-based" smoothed extended finite element method (ESm-XFEM) is tailored to linear elastic fracture mechanics and, in this context, to outperform the standard XFEM. In the XFEM, the displacement-based approximation is enriched by the Heaviside and asymptotic crack tip functions using the framework of partition of unity. This eliminates the need for the mesh alignment with the crack and re-meshing, as the crack evolves. Edge-based smoothing (ES) relies on a generalized smoothing operation over smoothing domains associated with edges of simplex meshes, and produces a softening effect leading to a close-to-exact stiffness, "super-convergence" and "ultra-accurate" solutions. The present method takes advantage of both the ES-FEM and the XFEM. Thanks to the use of strain smoothing, the subdivision of elements intersected by discontinuities and of integrating the (singular) derivatives of the approximation functions is suppressed via transforming interior integration into boundary integration. Numerical examples show that the proposed method improves significantly the accuracy of stress intensity factors and achieves a near optimal convergence rate in the energy norm even without geometrical enrichment or blending correction. [less ▲]

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See detailExtended Finite Element Method with Global Enrichment
Agathos, Konstantinos; Chatzi, Eleni; Bordas, Stéphane UL et al

Scientific Conference (2015, July)

A variant of the extended finite element method is presented which facilitates the use of enriched elements in a fixed volume around the crack front (geometrical enrichment) in 3D fracture problems. The ... [more ▼]

A variant of the extended finite element method is presented which facilitates the use of enriched elements in a fixed volume around the crack front (geometrical enrichment) in 3D fracture problems. The major problem associated with geometrical enrichment is that it significantly deteriorates the conditioning of the resulting system matrices, thus increasing solution times and in some cases making the systems unsolvable. For 2D problems this can be dealt with by employing degree of freedom gathering [1] which essentially inhibits spatial variation of enrichment function weights. However, for the general 3D problem such an approach is not possible since spatial variation of the enrichment function weights in the direction of the crack front is necessary in order to reproduce the variation of solution variables, such as the stress intensity factors, along the crack front. The proposed method solves the above problem by employing a superimposed mesh of special elements which serve as a means to provide variation of the enrichment function weights along the crack front while still not allowing variation in any other direction. The method is combined with special element partitioning algorithms [2] and numerical integration schemes [3] as well as techniques for the elimination of blending errors between the standard and enriched part of the approximation in order to further improve the accuracy of the produced results. Additionally, a novel benchmark problem is introduced which enables the computation of displacement and energy error norms as well as errors in the stress intensity factors for the general 3D case. Through this benchmark problem it is shown that the proposed method provides optimal convergence rates, improved accuracy and reduced computational cost compared to standard XFEM. [less ▲]

Detailed reference viewed: 606 (10 UL)
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See detailAn extended finite element method with smooth nodal stress
Peng, Xuan; Kulasegaram, Sivakumar; Bordas, Stéphane UL et al

Report (n.d.)

Detailed reference viewed: 99 (3 UL)
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See detailAn Extended Flexible Job Shop Scheduling Problem with Parallel Operations
Tessaro Lunardi, Willian UL; Voos, Holger UL

in ACM SIGAPP Applied Computing Review (2018), 18(2), 46-56

Traditional planning and scheduling techniques still hold important roles in modern smart scheduling systems. Realistic features present in modern manufacturing systems need to be incorporated into these ... [more ▼]

Traditional planning and scheduling techniques still hold important roles in modern smart scheduling systems. Realistic features present in modern manufacturing systems need to be incorporated into these techniques. Flexible job-shop scheduling problem (FJSP) is one of the most challenging combinatorial optimization problems. FJSP is an extension of the classical job shop scheduling problem where an operation can be processed by several different machines. In this paper, we consider the FJSP with parallel operations (EFJSP) and we propose and compare a discrete firefly algorithm (FA) and a genetic algorithm (GA) for the problem. Several FJSP and EFJSP instances were used to evaluate the performance of the proposed algorithms. Comparisons among our methods and state-of-the-art algorithms are also provided. The experimental results demonstrate that the FA and GA achieved improvements in terms of efficiency and efficacy. Solutions obtained by both algorithms are comparable to those obtained by algorithms with local search. In addition, based on our initial experiments, results show that the proposed discrete firefly algorithm is feasible, more effective and efficient than our proposed genetic algorithm for the considered problem. [less ▲]

Detailed reference viewed: 79 (18 UL)
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See detailExtended higher spin holography and Grassmannian models
Creutzig, Thomas; Hikida, Yasuaki; Roenne, Peter Browne UL

in Journal of High Energy Physics [=JHEP] (2013)

Detailed reference viewed: 53 (5 UL)
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See detailExtended mutation analysis and association studies of Nurr1 (NR4A2) in Parkinson disease.
Hering, R.; Petrovic, S.; Mietz, E.-M. et al

in Neurology (2004), 62(7), 1231-2

Detailed reference viewed: 55 (0 UL)
See detailExtended Quantum Model For Porous Silicon Formation
Münder, H.; Frohnhoff, St; Berger, M. G. et al

in Mat. Res. Soc. Symp. Proc. Vol. 358 (1995)

Detailed reference viewed: 14 (0 UL)
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See detailAn Extended Quantum Model for Porous Silicon Formation
Frohnhoff, St; Marso, Michel UL; Berger, M. G. et al

in Journal of the Electrochemical Society (1995), 142(1995), 615-620

Detailed reference viewed: 35 (0 UL)
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See detailAn Extended Solow Growth Model with Emigration: Transitional Dynamics and Skills Complementarity
Pieretti, Patrice UL; Zou, Benteng UL

in Economics Bulletin (2007), 6(35), 1-11

In this paper we develop an extended Solow growth model with skilled labor emigration which aggregates different labor types from strict complementarity to perfect substitution. Except in two particular ... [more ▼]

In this paper we develop an extended Solow growth model with skilled labor emigration which aggregates different labor types from strict complementarity to perfect substitution. Except in two particular cases, balanced growth paths can only be attained asymptotically. We therefore derive an analytical characterization of the transitional dynamics of the model. We are thus able to study the impact of labor elasticity of substitution on the time pattern of per capita income in the country that experiences brain drain. Simulations show that the shape of per capita trajectory depends crucially on the degree of complementarity (substitutability) between labor skills. Given that no income trajectory dominates the others, there is room for policy issues by influencing the elasticity of substitution (Klump and Preissler, 2000). [less ▲]

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See detailExtended space-time finite elements for landslide dynamics
Pasenow, F.; Zilian, Andreas UL; Dinkler, D.

in International Journal for Numerical Methods in Engineering (2013), 93(3), 329-354

The paper introduces a methodology for numerical simulation of landslides experiencing considerable deformations and topological changes. Within an interface capturing approach, all interfaces are ... [more ▼]

The paper introduces a methodology for numerical simulation of landslides experiencing considerable deformations and topological changes. Within an interface capturing approach, all interfaces are implicitly described by specifically defined level-set functions allowing arbitrarily evolving complex topologies. The transient interface evolution is obtained by solving the level-set equation driven by the physical velocity field for all three level-set functions in a block Jacobi approach. The three boundary-coupled fluid-like continua involved are modeled as incompressible, governed by a generalized non-Newtonian material law taking into account capillary pressure at moving fluid-fluid interfaces. The weighted residual formulation of the level-set equations and the fluid equations is discretized with finite elements in space and time using velocity and pressure as unknown variables. Non-smooth solution characteristics are represented by enriched approximations to fluid velocity (weak discontinuity) and fluid pressure (strong discontinuity). Special attention is given to the construction of enriched approximations for elements containing evolving triple junctions. Numerical examples of three-fluid tank sloshing and air-water-liquefied soil landslides demonstrate the potential and applicability of the method in geotechnical investigations. © 2012 John Wiley & Sons, Ltd. [less ▲]

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See detailExtended Survivable Passive Access Network (e-SPAN)
Wasim, Muhammad Umer UL; Zaidi, Syed Muhammad Hassan; Raja, Yasin et al

in Symposium on High Capacity Optical Networks and Enabling Technologies (HONET), September 6-8, Charlotte (NC) USA. (2006)

Wavelength Division Multiplexed based Passive Optical Networks (WDM-PON) are subjected to wide variety of incidental failures. It is preferred in WDM-PONs to provide fault management (survivability) at ... [more ▼]

Wavelength Division Multiplexed based Passive Optical Networks (WDM-PON) are subjected to wide variety of incidental failures. It is preferred in WDM-PONs to provide fault management (survivability) at link layer level. In this paper, our objective is to determine the factors, which can increase the scope of survivability at link layer, not available currently. We propose a cost-effective recovery mechanism, called ldquoExtended Survivable Passive Access Networkrdquo (e-SPAN). e SPAN is a multi-level protection scheme that has potential to corrects eventual errors that are caused by the transmission system by using different forward error correcting codes at receiver end, thus allowing us to have better performance budget in terms of BER and extended transmission distance of 8 to 12 Km. [less ▲]

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See detailAn Extended Systematic Literature Review on Provision of Evidence for Safety Certification
Nair, Sunil; de la Vara, Jose Luis; Sabetzadeh, Mehrdad UL et al

in Information & Software Technology (2014), 56(7), 689717

Detailed reference viewed: 186 (14 UL)
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See detaileXtended Variational Quasicontinuum Methodology for Modelling of Crack Propagation in Discrete Lattice Systems
Rokos, Ondrej; Peerlings, Ron; Zeman, Jan et al

Scientific Conference (2017, July 17)

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See detailExtending a key-chain based certified email protocol with transparent TTP
Liu, Z.; Pang, Jun UL; Zhang, C.

in Proc. 6th IEEE/IFIP Symposium on Trusted Computing and Communications (2010)

Detailed reference viewed: 53 (0 UL)