Browse ORBi by ORBi project The Open Access movement
ORBi is a project of

 Last 7 days     Results 1701-1720 of 57066.   81 82 83 84 85 86 87 88 89 90 91   Topology optimization for minimum weight with compliance and simpli ed nominal stress constraints for fatigue resistanceCollet, Maxime ; Bruggi, Matteo; Duysinx, Pierre in Structural and Multidisciplinary Optimization (2016)This work investigates a simpli ed approach to cope with the optimization of preliminary design of structures under local fatigue constraints along with a global enforcement on the overall compliance. The ... [more ▼]This work investigates a simpli ed approach to cope with the optimization of preliminary design of structures under local fatigue constraints along with a global enforcement on the overall compliance. The problem aims at the minimization of the weight of linear elastic structures under given loads and boundary conditions. The expected sti ness of the optimal structure is provided by the global constraint, whereas a set of local stress-based constraints ask for a structure to be fatigue resistant. A modi ed Goodman fatigue strength comparison is implemented through the same formalism to address pressure-dépendent failure in materials as in Drucker-Prager strength criterion. As a simplification, the Sines approach is used to de ne the equivalent mean and alternating stresses to address the fatigue resistance for an infinite life time. Sines computation is based on the equivalent mean and alternate stress depending on the invariants of the stress tensor and itsdeviatoric part, respectively. The so-called singularity phenomenon is overcome by the implementation of a suitable qp-relaxation of the equivalent stress measures. Numerical examples are presented to illustrate the features of the achieved optimal layouts and of the proposed algorithm. [less ▲]Detailed reference viewed: 18 (6 ULg) A simple calibration approach based on film-casting for confocal Raman microscopy to support the development of a Hot-Melt Extrusion processNetchacovitch, Lauranne ; Thiry, Justine ; De Bleye, Charlotte et alin Talanta (2016), 154When developing a new formulation, the development, calibration and validation steps of analytical methods based on vibrational spectroscopy are time-consuming. For each new formulation, real samples must ... [more ▼]When developing a new formulation, the development, calibration and validation steps of analytical methods based on vibrational spectroscopy are time-consuming. For each new formulation, real samples must be produced and a “reference method” must be used in order to determine the Active Pharmaceutical Ingredient (API) content of each sample. To circumvent this issue, the paper presents a simple approach based on the film-casting technique used as a calibration tool in the framework of hot-melt extrusion process. Confocal Raman microscopic method was successfully validated for the determination of itraconazole content in film-casting samples. Then, hot-melt extrusion was carried out to produce real samples in order to confront the results obtained with confocal Raman microscopy and Ultra High Performance Liquid Chromatography (UHPLC). The agreement between both methods was demonstrated using a comparison study based on the Bland and Altman’s plot. [less ▲]Detailed reference viewed: 73 (23 ULg) Simulation of a two-slope pyramid made by SPIF using an adaptive remeshing method with solid-shell finite elementVelosa De Sena, José ; Guzmán Inostroza, Carlos Felipe ; Duchene, Laurent et alin International Journal of Material Forming (2016), 9(3), 259-434Single point incremental forming (SPIF) is an emerging application in sheet metal prototyping and small batch production, which enables dieless production of sheet metal parts. This research area has ... [more ▼]Single point incremental forming (SPIF) is an emerging application in sheet metal prototyping and small batch production, which enables dieless production of sheet metal parts. This research area has grown in the last years, both experimentally and numerically. However, numerical investigations into SPIF process need further improvement to predict the formed shape correctly and faster than current approaches. The current work aims the use of an adaptive remeshing technique, originally developed for shell and later extended to 3D “brick” elements, leading to a Reduced Enhanced Solid-Shell formulation. The CPU time reduction is a demanded request to perform the numerical simulations. A two-slope pyramid shape is used to carry out the numerical simulation and modelling. Its geometric difficulty on the numerical shape prediction and the through thickness stress behaviour are the main analysis targets in the present work. This work confirmed a significant CPU time reduction and an acceptable shape prediction accuracy using an adaptive remeshing method combined with the selected solid-shell element. The stress distribution in thickness direction revealed the occurrence of bending/unbending plus stretching and plastic deformation in regions far from the local deformation in the tool vicinity. [less ▲]Detailed reference viewed: 59 (32 ULg) Is there an alphabet of Moroccan cuisine? Notes on the materiality of cooking and eating.Mescoli, Elsa Conference (2016, July)Short Abstract Stemming from the ethnographic material collected during an eighteen months fieldwork conducted among a group Moroccan of women in Milan to study their food practices, this paper focuses on ... [more ▼]Short Abstract Stemming from the ethnographic material collected during an eighteen months fieldwork conducted among a group Moroccan of women in Milan to study their food practices, this paper focuses on the materiality of cooking and eating through adopting a micro-structural approach. Long Abstract Inspired by the work of Lévi-Strauss (1964) aimed at identifying the relationships of mutual intelligibility underlying some social and cultural facts such as the treatment of food, this paper will focus on the materiality of cooking and eating through adopting a micro-structural approach. The ethnographic data collected during an eighteen months fieldwork conducted among a group of Moroccan women in Milan to study their cooking and eating habits will be analysed by paying particular attention to the practices and elements that made the "alphabet" of Moroccan cuisine. This means that, if we considered dishes as complex sentences which can be deciphered by people that share a same language, we could try to identify the littlest components that made them happen. Which norms regulated the combination of ingredients? Which ways of cooking described this food culture? Which gestures and embodied knowledge seemed essential to give an intelligible cultural connotation to the cooking and eating of food? Which variations were admitted? The analysis of the actors' discourses and practices will show how Lévi-Strauss approach and model to the study of foodways can meet a material culture approach and still be relevant nowadays. [less ▲]Detailed reference viewed: 41 (1 ULg) Real-time capture of the folding-unfolding transitions in a single oligorotaxane foldamerSluysmans, Damien ; Hubert, Sandrine ; Bruns, Carson et alScientific conference (2016, July)Detailed reference viewed: 4 (2 ULg) From nature to culture? Lévi-Strauss' legacy and the study of contemporary foodwaysMescoli, Elsa ; Graf, KatharinaConference (2016, July)n the first volume of his Mythologiques, entitled The Raw and the Cooked, Claude Lévi-Strauss argued that the preparation of food is a form of language that reveals a society's structure. For Lévi-Strauss ... [more ▼]n the first volume of his Mythologiques, entitled The Raw and the Cooked, Claude Lévi-Strauss argued that the preparation of food is a form of language that reveals a society's structure. For Lévi-Strauss, the so-called culinary triangle of the raw, the rotten and the cooked represents a semantic field within which the various forms of transformation of food from nature into culture play a key role. Since Lévi-Strauss, following extensive changes to food production, preparation and consumption, the notion of cooking has become ever more diversified, and became increasingly contentious. Yet, the multiple ways of combining and processing ingredients still give social and cultural meanings to food and trigger the creation of sociabilities and belongings through its own destruction (Gell 1986). This panel aims to explore Levi-Strauss' legacy and evaluate its usefulness in today's context from different angles, ranging from domestic food preparation to industrial production and global circulations of food. To what extent can this concept still provide an interpretative framework of topical food issues? Which contemporary myths does it shed light on? How could it be deployed to read the history of food and link it to contemporary questions? This panel welcomes papers on the history of food preparation, contemporary food preparation, including debates in professional and multimedia circles, various forms of food production and the possible transformation of food within globalised food markets. Although mobilizing a classic anthropological theory, this panel aims to be interdisciplinary and to present a diverse range of analytical perspectives. [less ▲]Detailed reference viewed: 41 (0 ULg) Solo vs. duet in different virtual rooms: On the consistency of singing quality across conditionsFischinger, Timo; Kreutz, Gunter; Larrouy, Pauline Poster (2016, July)Previous research on vocal pitch accuracy revealed insights into the fundamentals of singing. However, most of the research on singing focused on the analysis of single voices, whereas few aYempts have ... [more ▼]Previous research on vocal pitch accuracy revealed insights into the fundamentals of singing. However, most of the research on singing focused on the analysis of single voices, whereas few aYempts have been made to tackle the challenge of analyzing mulTtrack recordings of singing ensembles. In addiTon, singers have to adjust their way of singing with respect to a given venue’s acousTcal environment (e.g., small room vs. a comparaTvely large space like a church). If it is common that musical performances are greatly influenced by room acousTcs, studies on the effects of room acousTcal features during ensemble singing are rare. In order to invesTgate singing performances across various condiTons, we manipulated the singing condiTon (unison, canon, solo) as well as the acousTcal feedback by applying diverging virtual rooms. Three duets with female singers (N = 6) were asked to sing three different melodies using headset microphones to record each singer separately. Recordings took place in the communicaTon acousTc simulator (CAS) at the House of Hearing (Oldenburg, Germany) to be able to provide different simulated acousTcal spaces (i.e., cathedral, classroom, and dry condiTon) to the singers. ObjecTve measures were performed on each recording and confirmed that the singers sang the melodies with high precision (small pitch interval deviaTons) hardly affected by singing condiTons or by the type of acousTcal feedback. However, the singers tended to driH (larger deviaTons of the tonal center) when singing in canon compared to solo and unison singing. Overall, the analysis of the pitch accuracy showed a general effect of condiTon (i.e., unison, canon, solo), but no general effect of acousTcal feedback and no interacTon between the two variables under study. [less ▲]Detailed reference viewed: 12 (1 ULg) Soyons optimistesRADERMECKER, Régis in Revue de l'Association Belge du Diabète (2016), 59(4), 3Detailed reference viewed: 22 (2 ULg) Perception of pitch accuracy in melodies: A categorical or continuous phenomenon?Larrouy, Pauline ; Franz, Simone; Poeppel, DavidConference (2016, July)In western music, a semitone constitutes a theoretical and perceptual boundary between tones and is defined as a unit for categorical perception of intervals (Burns & Ward, 1978). However, melodic ... [more ▼]In western music, a semitone constitutes a theoretical and perceptual boundary between tones and is defined as a unit for categorical perception of intervals (Burns & Ward, 1978). However, melodic perception does not rely exclusively on this category but also involves the notion of ‘correctness’. If we usually classify melodies as “in tune” or “out of tune” depending on the size of interval deviations (smaller than a semitone) along melodies, the transition between the two categories remains unclear. This study examines the process involved in pitch accuracy perception. Twenty-five participants identified melodies as “in tune” or “out of tune” and rated their confidence for each answer. The pitch manipulation consisted of the enlargement of an interval in 5 cent steps (from 0 to 50 cent deviation). The interval deviated was either a Major 2nd or a Perfect 4th and occurred in the middle or end of a 6-tone melody. The task was run twice, before and after an explicit definition of the two labels. Repeated measure ANOVAs were conducted to examine the effect of the deviation on the proportion of in- tune answers and on the confidence levels. For the participants who were able to learn the labels (n = 20), the proportion of in tune answers varies greatly according to the amplitude of the deviation and depended on the size of the interval manipulated. Associated with the confidence level measurement, the identification data support a categorical perception process. Interestingly, explicitly learning the labels increased the overall confidence but did not modify drastically the profile of the categories and the process behind the categorization. This study suggests that explicit learning is not necessary to develop higher order categories relative to “correctness”. Nevertheless, such a process seems limited to certain intervals. Further investigation of other intervals and individual differences seems promising to better understand the mechanisms underlying music perception. [less ▲]Detailed reference viewed: 32 (3 ULg) Les mustères de la "Viege noire" ou comment se passe la demande d'allocation de handicapMarquet, Françoise; RADERMECKER, Régis in Revue de l'Association Belge du Diabète (2016), 59(4), 9-13Detailed reference viewed: 20 (1 ULg) How should we study the light distribution of strong lensing galaxies ?Biernaux, Judith Poster (2016, July)Detailed reference viewed: 9 (1 ULg) Integration of Composites for Greener Engine - Rapport scientifique & techniqueAatach, Mohamed ; Gaydardzhiev, Stoyan Report (2016)The project's objective is to achieve a greater integration of composite materials in the low-pressure compressor, major product of Techspace Aero. The recycling of composite materials is one of the main ... [more ▼]The project's objective is to achieve a greater integration of composite materials in the low-pressure compressor, major product of Techspace Aero. The recycling of composite materials is one of the main parts of this project. The focus is on the review of technologies, reuse and resulting properties on the recycling of fibre reinforced polymers and the development of new processes for end-of-life aerospace grade advanced carbon fiber reinforced composite materials (electrodynamic and conventional fragmentation, physicochemical characterization, environmental impact assessment, etc.) [less ▲]Detailed reference viewed: 25 (1 ULg) Quadratic reformulations of nonlinear binary optimization problemsCrama, Yves Conference (2016, July)A {\em pseudo-Boolean function} is a real-valued function $f(x)=f(x_1,x_2,\ldots,x_n)$ of $n$ binary variables, that is, a mapping from $\{0,1\}^n$ to $\mathbf R$. \emph{Nonlinear binary optimization ... [more ▼]A {\em pseudo-Boolean function} is a real-valued function $f(x)=f(x_1,x_2,\ldots,x_n)$ of $n$ binary variables, that is, a mapping from $\{0,1\}^n$ to $\mathbf R$. \emph{Nonlinear binary optimization problems} of the form $$\label{eq:PBO} \min \{ f(x) : x \in \{0,1\}^n \},$$, where $f$ is a pseudo-Boolean function expressed as a multilinear polynomial in its variables, are notoriously difficult. For a pseudo-Boolean function $f(x)$ on $\{0,1\}^n$, we say that $g(x,y)$ is a \emph{quadratization} of $f$ if $g(x,y)$ is a quadratic polynomial depending on $x$ and on $m$ \emph{auxiliary} binary variables $y_1,y_2,\ldots,y_m$ such that $f(x)= \min \{ g(x,y) : y \in \{0,1\}^m \}$ for all $x \in \{0,1\}^n$. By means of quadratizations, minimization of $f$ is reduced to minimization (over the extended set of variables) of the quadratic function $g(x,y)$. This is of practical interest because minimization of quadratic functions has been thoroughly studied for the last few decades, and much progress has been made in solving such problems exactly or heuristically. This talk addresses two main types of questions. First, we want to determine the minimum number of auxiliary $y$-variables required in a quadratization of an arbitrary function~$f$. This question is rather natural since the complexity of minimizing the quadratic function $g(x,y)$ heavily depends (among other factors) on the number of binary variables~$(x,y)$. We establish tight lower and upper bounds on the number of auxiliary variables needed in such a reformulation. Next, we determine more precisely the number of auxiliary variables required by quadratizations of \emph{symmetric} pseudo-Boolean functions $f(x)$, i.e., functions whose value only depends on the number of variables equal to~$1$. [less ▲]Detailed reference viewed: 13 (1 ULg) Real-time capture of the folding-unfolding transitions in a single oligorotaxane foldamerSluysmans, Damien ; Hubert, Sandrine ; Bruns, Carson et alPoster (2016, July)Detailed reference viewed: 22 (0 ULg) On the relations between nonlinear resonances and nonlinear normal modesDetroux, Thibaut ; Noël, Jean-Philippe ; Kerschen, Gaëtan Conference (2016, July)Detailed reference viewed: 11 (2 ULg) De l’activation à la précarité : analyse de deux dispositifs d’intervention socialeGérard, Julie ; Vrancken, Didier Conference (2016, July)La lutte contre le chômage de longue durée et l’exclusion sociale par un retour à l’emploi représentent des enjeux essentiels des politiques actives du marché du travail. C’est pourquoi, cette ... [more ▼]La lutte contre le chômage de longue durée et l’exclusion sociale par un retour à l’emploi représentent des enjeux essentiels des politiques actives du marché du travail. C’est pourquoi, cette communication s’intéresse aux effets de l’intervention sociale sur les demandeurs d’emploi à partir de l’analyse de deux dispositifs d’activation situés en Belgique francophone : une Entreprise de Formation par le Travail et une agence de Titres-Services. Au moyen d’une étude qualitative reposant sur une soixantaine d’observations de situations d’interactions réalisée entre bénéficiaires et « travailleurs du social » (consultant, assistant social, formateur, etc.) et, d’une quarantaine d’entretiens semi-directifs, nous rendrons compte de l’action de ces deux dispositifs dans le domaine de l’insertion-socioprofessionnelle. Nous illustrerons combien, par l’articulation de politiques d’emploi à vocation universelle et de politiques particularistes destinées aux personnes les plus fragiles, ces dispositifs génèrent de véritables trappes à précarité. À terme, nous montrerons combien le maintien de ces dernières soulève la question du développement progressif d’un nouveau régime de protections, opérant a minima, voire par défaut, auprès des publics peu qualifiés face à la menace sourde que font peser le marché noir et, plus largement, l’informalité du travail. [less ▲]Detailed reference viewed: 59 (7 ULg) Disrupted interaction between self and memory in patients with Alzheimer’s diseaseGenon, Sarah ; Salmon, Eric ; Collette, Fabienne et alConference (2016, July)In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship ... [more ▼]In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship can be disrupted. This was evidenced by impaired SRE and SRRE in AD for recognition of adjectives previously judged for self-relevance, as well as recall of names of people previously linked to the self. For both materials, a qualitative impairment of the recollective experience for the self-related items was also observed in AD. A neuroimaging approach suggested that reduced SRE is related to decreased grey matter volume in the lateral prefrontal cortex (lPFC). Thus, retrieval of recent self-related memories is impaired in relation to altered high-order processes in lPFC in AD. [less ▲]Detailed reference viewed: 70 (4 ULg) European Commission, trade agreements, and diversity of cultural expressions: between autonomy and influenceVlassis, Antonios in European Journal of Communication (2016), 31(4)The Convention on diversity of cultural expressions – adopted by United Nations Educational, Scientific and Cultural Organization in 2005 – is a main international instrument within the global governance ... [more ▼]The Convention on diversity of cultural expressions – adopted by United Nations Educational, Scientific and Cultural Organization in 2005 – is a main international instrument within the global governance of cultural and audiovisual industries. For its part, the European Commission played a critical role in the negotiation, leading to the Convention on Diversity of Cultural Expressions’ adoption. In this respect, the article aims to explore why and how the Commission uses the Convention on Diversity of Cultural Expressions throughout the recent European Union trade negotiations, for which purposes and how the Convention on Diversity of Cultural Expressions influences the European Union foreign policy and its objectives. The article is more concerned with analysing the policy process through which the Commission’s strategy is formulated in light of the Convention on Diversity of Cultural Expressions and of the place of cultural and audiovisual industries within the European Union trade agreements and also concerned with understanding whether the Commission’s autonomy is transformed into influence within the policy process. [less ▲]Detailed reference viewed: 12 (3 ULg) Interactions entre élèves et phase de correction collective face à une tâche complexe de mathématiques : facteurs susceptibles de soutenir les apprentissages ou prothèses externes pour résoudre ?Fagnant, Annick ; Demonty, Isabelle; Dupont, Virginie et alConference (2016, July)Detailed reference viewed: 27 (2 ULg) The mechanical control of peri-implant bone remodeling investigated by in vivo imaging and in silico modelingLi, Zihui; Betts, Duncan; Kuhn, Gisela et alConference (2016, July)Detailed reference viewed: 12 (1 ULg)