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  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    AntipovDenis; DoerrBenjamin;
    Publisher: HAL CCSD
    Country: France

    To gain a better theoretical understanding of how evolutionary algorithms (EAs) cope with plateaus of constant fitness, we propose the n -dimensional \textsc {Plateau} _k function as natural benchmark and analyze how different variants of the (1 + 1) EA optimize it. The \textsc {Plateau} _k function has a plateau of second-best fitness in a ball of radius k around the optimum. As evolutionary algorithm, we regard the (1 + 1) EA using an arbitrary unbiased mutation operator. Denoting by \alpha the random number of bits flipped in an application of this operator and assuming that \Pr [\alpha = 1] has at least some small sub-constant value, we show the surprising result that for all constant k \ge 2 , the runtime T follows a distribution close to the geometric one with success probability equal to the probability to flip between 1 and k bits divided by the size of the plateau. Consequently, the expected runtime is the inverse of this number, and thus only depends on the probability to flip between 1 and k bits, but not on other characteristics of the mutation operator. Our result also implies that the optimal mutation rate for standard bit mutation here is approximately k/(en) . Our main analysis tool is a combined analysis of the Markov chains on the search point space and on the Hamming level space, an approach that promises to be useful also for other plateau problems.

  • Closed Access English
    Authors: 
    Yves Fotso Fotso; Suzanne Touzeau; Berge Tsanou; Frédéric Grognard; Samuel Bowong;
    Publisher: HAL CCSD
    Country: France

    International audience; Coffee production is an important agriculture activity which contributes significantly to the economic growth of many countries in the world. One of the major constraints to coffee production throughout the world is the damage caused by the coffee berry borer (CBB), Hypothenemus hampei (Coleoptera: Scolytidae). It is the most damaging insect pest to coffee production in the world. These insects infest coffee berries, preferably mature berries, and spend most of their life cycle inside the berries, which make them quite difficult to control. In this work, we introduce and analyse a berry age-structured model describing the infestation dynamics of coffee berries by CBB. Using the semigroup theory in the case of Lipschitz perturbation, we show that the model has a unique nonnegative and bounded solution. We derive an explicit formula of the basic reproduction number, R0, using the next generation approach and the biological interpretation of this threshold in a specific case. Numerical simulations are carried out to illustrate the theoretical results.

  • English
    Authors: 
    de Largy Healy, Jessica;
    Publisher: HAL CCSD
    Country: France

    International audience; Dr Joseph Neparrŋa Gumbula (1954–2015) was an exceptional man. Born in the small mission settlement of Milingimbi, off the central coast of Arnhem Land, this Gupapuyŋu ceremonial leader spent the last 10 years of his life traveling to museums and archives in Australia and abroad to study, document and digitize expressions of his ancestral legacy. Widely recognized in academia for his knowledge of Arnhem Land material cultures and ceremonial performance, and for his inspiring role as a lecturer and educator, the research methodologies Joe Gumbula put in practice during his career had lasting effects on museum professionals and scholars internationally. They led to a myriad of innovative collaborations within the ‘relational museum’ paradigm and to a broader and finer appreciation of Yolngu systems of value. In this chapter, I draw on the Yolŋu concept of pathways (dhukarr, wayawu) to explore the nature of his engagement with collections and his contribution to value creation processes within and outside of the museum sphere.

  • English
    Authors: 
    Arora, Cheshta; Prabhakar, Tarunima;
    Publisher: HAL CCSD
    Country: France

    The paper reflects on the practices of an interdisciplinary team consisting of researchers and activists from the field of computer science and social sciences involved in developing a user-facing, browser plug-in to detect and moderate instances of online gender based-violence, hate speech and harassment in Hindi, Indian English, and Tamil. The plug-in is based on machine learning (ML) approaches to detect and moderate online content while also offering other non-ML features that can help mitigate the experience of gender-based online violence and hate speech.There have been multiple calls within the field of Human-Computer Interaction (HCI) to include qualitative methods in one’s research design. These calls, while attuned to the importance of qualitative methods for HCI, ignore the intercurrent nature of different research methods, disciplines, and practices. The paper draws from the team discussions that were focussed on defining the nature and extent of online gendered violence, use-cases for the tool, differences and scepticism expressed in using ML approaches to reflect on how each disciplinary approach evokes a temporality within which the problem is framed.The paper borrows the concept of intercurrence from Orren & Skowronek (1996) and reorients it to explicate the practice of interdisciplinary research. It argues that to mark the intercurrence i.e., the multiple temporalities that inform different researchers and methods, is to mark the singularity of interdisciplinary practices wherein to be interdisciplinary is not a question of integration, blending, transcending—metaphors that are often invoked to introduce a research method from one discipline to another. These existing metaphors do not capture the contingencies and incongruencies that inform interdisciplinary practices wherein it is not just the epistemological concerns that are at stake but different temporalities that situate research methods and researchers.

  • Open Access English
    Authors: 
    Rosalia Ferreri; Simona Genovese; Marco Barra; Ilaria Biagiotti; Jean-Hervé Bourdeix; Andrea De Felice; Denis Gašparević; Tarek Hattab; Magdalena Iglesias; Tea Juretić; +7 more
    Publisher: HAL CCSD
    Countries: France, Croatia, Spain

    Size at first sexual maturity (L50) represents an important life-history trait that needs to be considered in the development of management measures as it provides fundamental information for avoiding the exploitation of younger individuals. L50 is known to display variability due to fishing pressure, geographical gradients, and environmental features. In this study, to investigate L50 variability among areas in the Mediterranean and Black Seas, maturity ogives of anchovies (Engraulis encrasicolus) were estimated by considering samples collected during the anchovy spawning period in the framework of the MEDiterranean International Acoustic Survey (MEDIAS) program. Anchovy size and sexual maturity data from several geographical subareas (GSAs), i.e., northern Spain, Gulf of Lion, Tyrrhenian Sea, Strait of Sicily, Adriatic Sea and Black Sea, were gathered according to a standard methodological protocol. Maturity ogives were estimated by a logistic regression considering total length, condition factor, sex and GSA. The obtained results showed a significant effect of the condition factor, in that fish in better condition reached maturity earlier, and the results also indicated differences in L50 values among the areas and between the sexes, with males reaching maturity at lower lengths than females. Even though the obtained L50 estimates are relative to the spawning period only, the variability observed at the Mediterranean basin scale highlights the importance of explicitly considering specific habitat characteristics when providing management advice based on an ecosystem approach for fisheries.

  • English
    Authors: 
    Rehman, Abdul; Zaib, Alam; Azmat, Shoaib; Khattak, Shahid;
    Publisher: HAL CCSD
    Country: France

    The objective of this work is to detect the cell phone and/or camera used by a person in restricted areas. The paper is based on intensive image processing techniques, such as, features extraction and image classification. The dataset of images is generated with cell phone camera including positive (with cell phone) and negative (without cell phone) images. We then extract relevant features by using classical features extraction techniques including Histogram of Oriented Gradients (HOG) and Speeded up Robust Features (SURF).The extracted features are then, passed to classifier for detection. We employ Support Vector Machine (SVM), Nearest Neighbor (K-NN) and Decision tree classifier which are already trained on our dataset of training images of persons using mobile or otherwise. Finally, the detection performance in terms of error rate is compared for various combinations of feature extraction and classification techniques. Our results show that SURF with SVM classifier gives the best accuracy.

  • English
    Authors: 
    Jens Gustedt;
    Publisher: HAL CCSD
    Country: France

    Over time C has integrated some new features as keywords (some genuine, some from C++) but the naming strategy has not be entirely consistent: some were integrated using non-reserved names (const, inline) others were integrated in an underscore-capitalized form. For some of them, the use of the lower-case form then is ensured via a set of library header files. The reason for this complicated mechanism had been backwards compatibility for existing code bases. Since now years or even decades have gone by, we think that it is time to switch and to use to the primary spelling. This is a revsion of papers to N2368 and N2392 where we reduce the focus to the list of keywords that found consensus in the WG14 London~2019 meeting. Other papers will build on this for those keywords or features that need more investigation.

  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Buitrago Boret, Saúl,; Escalante, René; Villasana, Minaya;
    Publisher: HAL CCSD
    Country: France

    In this paper we study some deterministic mathematical models that seek to explain the expansion of zika virus, as a viral epidemic, using published data for Brazil. SIR type models are proposed and validated using the epidemic data found, considering several aspects in the spread of the disease. Finally, we confirmed that the crucial epidemic parameter such as $R_0$ is consistent with those previously reported in the literature for other areas. We also explored variations of the parameters within Brazil for different federal entities. We concluded that a parsimonious model that includes both human and vector populations best describe the epidemic parameters.

  • English
    Authors: 
    Gruetzner, Georg,;
    Publisher: HAL CCSD
    Country: France

    We introduce a notion of discrete-conformal equivalence of closed convex polyhedra in Euclidean 3-space. Using this notion, we prove a uniformization theorem for closed convex polyhedra in Euclidean 3-space.

  • Publication . Preprint . Article . 2021
    Open Access English
    Authors: 
    Louis, Ruben;
    Publisher: HAL CCSD
    Country: France

    This paper shows that a weak symmetry action of a Lie algebra g on a singular foliation F induces a unique (up to homotopy) Lie ∞-morphism from g to the DGLA of vector fields on a universal N Q-manifold over F. Also, an explicit formula of such Lie ∞-morphism is given for some N Q-manifold of F which is not necessarily a universal one. We deduce from this general result several geometric consequences. For instance, we give an example of action of Lie algebra on a sub-affine variety which cannot be extended to the ambient space. Last, we introduce the notion of tower of bi-submersions over a singular foliations and lift symmetries to them.; HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

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