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Vertex Degrees in Planar Maps [article]

Gwendal Collet, Michael Drmota, Lukas Daniel Klausner
2016 arXiv   pre-print
We prove a general multi-dimensional central limit theorem for the expected number of vertices of a given degree in the family of planar maps whose vertex degrees are restricted to an arbitrary (finite or infinite) set of positive integers D. Our results rely on a classical bijection with mobiles (objects exhibiting a tree structure), combined with refined analytic tools to deal with the systems of equations on infinite variables that arise. We also discuss some possible extension to maps of higher genus.
arXiv:1605.04206v2 fatcat:eqsqzec6ivbbpa3p4u7kyc7nfu

Limit Laws of Planar Maps with Prescribed Vertex Degrees [article]

Gwendal Collet, Michael Drmota, Lukas Daniel Klausner
2018 arXiv   pre-print
We prove a general multi-dimensional central limit theorem for the expected number of vertices of a given degree in the family of planar maps whose vertex degrees are restricted to an arbitrary (finite or infinite) set of positive integers D. Our results rely on a classical bijection with mobiles (objects exhibiting a tree structure), combined with refined analytic tools to deal with the systems of equations on infinite variables that arise. We also discuss possible extensions to maps of higher genus and to weighted maps.
arXiv:1808.05944v1 fatcat:7yavczjoefgpzmykfdymchluve

Threshold functions for small subgraphs: an analytic approach [article]

Gwendal Collet, Élie de Panafieu, Danièle Gardy, Bernhard Gittenberger, Vlady Ravelomanana
2017 arXiv   pre-print
We revisit the problem of counting the number of copies of a fixed graph in a random graph or multigraph, including the case of constrained degrees. Our approach relies heavily on analytic combinatorics and on the notion of patchwork to describe the possible overlapping of copies. This paper is a version, extended to include proofs, of the paper with the same title to be presented at the Eurocomb 2017 meeting.
arXiv:1705.08768v1 fatcat:wwwwa4zy5zer7jvfuj46ah44p4

Threshold functions for small subgraphs in simple graphs and multigraphs [article]

Gwendal Collet, Élie de Panafieu, Danièle Gardy, Bernhard Gittenberger, Vlady Ravelomanana
2018 arXiv   pre-print
We revisit the problem of counting the number of copies of a fixed graph in a random graph or multigraph, for various models of random (multi)graphs. For our proofs we introduce the notion of patchworks to describe the possible overlappings of copies of subgraphs. Furthermore, the proofs are based on analytic combinatorics to carry out asymptotic computations. The flexibility of our approach allows us to tackle a wide range of problems. We obtain the asymptotic number and the limiting
more » ... on of the number of subgraphs which are isomorphic to a graph from a given set of graphs. The results apply to multigraphs as well as to (multi)graphs with degree constraints. One application is to scale-free multigraphs, where the degree distribution follows a power law, for which we show how to obtain the asymptotic number of copies of a given subgraph and give as an illustration the expected number of small cycles.
arXiv:1807.05772v1 fatcat:q6dea5zjmrhhdetphb6arpkmra

UMLtoGraphDB: Mapping Conceptual Schemas to Graph Databases [chapter]

Gwendal Daniel, Gerson Sunyé, Jordi Cabot
2016 Lecture Notes in Computer Science  
The need to store and manipulate large volume of (unstructured) data has led to the development of several NoSQL databases for better scalability. Graph databases are a particular kind of NoSQL databases that have proven their efficiency to store and query highly interconnected data, and have become a promising solution for multiple applications. While the mapping of conceptual schemas to relational databases is a well-studied field of research, there are only few solutions that target
more » ... l modeling for NoSQL databases and even less focusing on graph databases. This is specially true when dealing with the mapping of business rules and constraints in the conceptual schema. In this article we describe a mapping from UML/OCL conceptual schemas to Blueprints, an abstraction layer on top of a variety of graph databases, and Gremlin, a graph traversal language, via an intermediate Graph metamodel. Tool support is fully available.
doi:10.1007/978-3-319-46397-1_33 fatcat:6sobmg3n5vcmfj5nmxgob4tkgu

Xatkit: A multimodal low-code chatbot development framework

Gwendal Daniel, Jordi Cabot, Laurent Deruelle, Mustapha Derras
2020 IEEE Access  
GWENDAL DANIEL received the Ph.D. degree with the AtlanMod Team, Ecole des Mines de Nantes, France, in 2017.  ...  Fernàndez Cecchetto for extending Xatkit with support for additional platforms and to Robert Clarisó and Daniel Caligari for his help during the empirical evaluation.  ...  The first two days focused on teaching core modeling principles while the last one included a remote presentation by Gwendal Daniel introducing Xatkit as an example of the use of model-based solution to  ... 
doi:10.1109/access.2020.2966919 fatcat:fsjem4gabra2foo5gkoelmsasu

Xatkit: A model-based chatbot development framework - Extended Abstract

Gwendal Daniel, Jordi Cabot, Laurent Deruelle, Mustapha Derras
2020 Congrès INFORSID  
To this purpose, we introduce Xatkit (Daniel et al., 2020) , a novel model-based chatbot development framework that aims to address this question using Model Driven Engineering (Brambilla et al., 2017  ... 
dblp:conf/inforsid/DanielCDD20 fatcat:igpboq4ulva4tbu7qtruodmzmm

A Model-based Chatbot Generation Approach to Converse with Open Data Sources [article]

Hamza Ed-douibi, Javier Luis Cánovas Izquierdo, Gwendal Daniel, Jordi Cabot
2020 arXiv   pre-print
The Open Data movement promotes the free distribution of data. More and more companies and governmental organizations are making their data available online following the Open Data philosophy, resulting in a growing market of technologies and services to help publish and consume data. One of the emergent ways to publish such data is via Web APIs, which offer a powerful means to reuse this data and integrate it with other services. Socrata, CKAN or OData are examples of popular specifications
more » ... publishing data via Web APIs. Nevertheless, querying and integrating these Web APIs is time-consuming and requires technical skills that limit the benefits of Open Data movement for the regular citizen. In other contexts, chatbot applications are being increasingly adopted as a direct communication channel between companies and end-users. We believe the same could be true for Open Data as a way to bridge the gap between citizens and Open Data sources. This paper describes an approach to automatically derive full-fledged chatbots from API-based Open Data sources. Our process relies on a model-based intermediate representation (via UML class diagrams and profiles) to facilitate the customization of the chatbot to be generated.
arXiv:2007.10503v1 fatcat:7l4y3mgbibcyvlm6cutwguwwwi

Scalable Queries and Model Transformations with the Mogwaï Tool [chapter]

Gwendal Daniel, Gerson Sunyé, Jordi Cabot
2018 Lecture Notes in Computer Science  
Scalability of modeling frameworks has become a major issue hampering MDE adoption in the industry. Specifically, scalable model persistence, as well as efficient query and transformation engines, are two of the key challenges that need to be addressed to enable the support for very large models in current applications. In this paper we demonstrate Mogwaï, a tool designed to efficiently compute queries and transformations (expressed in OCL and ATL) over models stored in NoSQL databases. Mogwaï
more » ... elies on a translational approach that maps constructs of the supported input languages to Gremlin, a generic NoSQL query language, and a model to datastore mapping allowing to compute the generated query on top of several datastores. The produced queries are computed on the database side, benefiting of all its optimizations, improving the execution time and reducing the memory footprint compared to standard solutions. The Mogwaï tool is released as a set of open source Eclipse plugins and is fully available online.
doi:10.1007/978-3-319-93317-7_9 fatcat:pizdxvh7pbcz7icx2vprhtupsy

Advanced prefetching and caching of models with PrefetchML

Gwendal Daniel, Gerson Sunyé, Jordi Cabot
2018 Journal of Software and Systems Modeling  
project=ocl Gwendal Daniel et al.  ... 
doi:10.1007/s10270-018-0671-8 fatcat:a27sbfhgijhapga3uymk3aluqq

Gremlin-ATL: A scalable model transformation framework

Gwendal Daniel, Frederic Jouault, Gerson Sunye, Jordi Cabot
2017 2017 32nd IEEE/ACM International Conference on Automated Software Engineering (ASE)  
Industrial use of Model Driven Engineering techniques has emphasized the need for efficiently store, access, and transform very large models. While scalable persistence frameworks, typically based on some kind of NoSQL database, have been proposed to solve the model storage issue, the same level of performance improvement has not been achieved for the model transformation problem. Existing model transformation tools (such as the well-known ATL) often require the input models to be loaded in
more » ... ry prior to the start of the transformation and are not optimized to benefit from lazy-loading mechanisms, mainly due to their dependency on current low-level APIs offered by the most popular modeling frameworks nowadays. In this paper we present Gremlin-ATL, a scalable and efficient model-to-model transformation framework that translates ATL transformations into Gremlin, a query language supported by several NoSQL databases. With Gremlin-ATL, the transformation is computed within the database itself, bypassing the modeling framework limitations and improving its performance both in terms of execution time and memory consumption. Tool support is available online.
doi:10.1109/ase.2017.8115658 dblp:conf/kbse/DanielJSC17 fatcat:i4ovwwglo5b5rpkgg4tzzznnwa

Circadian Clock Characteristics Are Altered in Human Thyroid Malignant Nodules

Tiphaine Mannic, Patrick Meyer, Frederic Triponez, Marc Pusztaszeri, Gwendal Le Martelot, Olivia Mariani, Daniel Schmitter, Daniel Sage, Jacques Philippe, Charna Dibner
2013 Journal of Clinical Endocrinology and Metabolism  
Context: Circadian clock represents the body's molecular time-keeping system. Recent findings revealed strong changes of clock gene expression in various types of human cancers. Objective: Due to emerging evidence on the connection between circadian oscillator, cell cycle and oncogenic transformation, we aimed to characterize the circadian clockwork in human benign and malignant thyroid nodules. Design: Clock transcript levels were assessed by quantitative RT-PCR in thyroid tissues. To provide
more » ... olecular characteristics of human thyroid clockwork, primary thyrocytes established from normal or nodular thyroid tissue biopsies were subjected to in vitro synchronization with subsequent clock gene expression analysis by circadian bioluminescence reporter assay, and by quantitative RT-PCR. Results : The expression levels of Bmal1 were up-regulated in tissue samples of Follicular Thyroid Carcinoma (FTC), and in Papillary Thyroid Carcinoma (PTC), as compared to normal thyroid and benign nodules, while Cry2 was down-regulated in FTC and PTC. Human thyrocytes derived from normal thyroid tissue exhibited high-amplitude circadian oscillations of Bmal1-luciferase reporter expression, and of endogenous clock transcripts. Thyrocytes established from FTC and PTC exhibited clock transcript oscillations similar to those of normal thyroid tissue and benign nodules (except for Per2 altered in PTC), while cells derived from Poorly Differentiated Thyroid Carcinoma (PDTC) exhibited altered circadian oscillations. Conclusions: This is the first study demonstrating a molecular makeup of human thyroid circadian clock. Characterization of the thyroid clock machinery alterations upon thyroid nodule malignant transformation contributes to understanding the connections between circadian clocks and oncogenic transformation. Moreover, it might help improving the thyroid nodule pre-operative diagnostics.
doi:10.1210/jc.2013-2568 pmid:23979949 fatcat:hpslswefijeyvhyil6k5v2fulq

Efficient Persistence and Query Techniques for Very Large Models

Gwendal Daniel
2016 ACM/IEEE International Conference on Model Driven Engineering Languages and Systems  
To address these issues we propose the MOGWAÏ (Daniel et al. 2016b ) query framework that is able to handle complex queries on large models.  ...  Experiments detailed in previous work (Daniel et al. 2016b ) have shown that using this approach brings a significant improvement both in terms of execution time and memory consumption.  ... 
dblp:conf/models/Daniel16 fatcat:oc7do4e47jc65bsfe3lo4qz6me

Improving Memory Efficiency for Processing Large-Scale Models

Gwendal Daniel, Gerson Sunyé, Amine Benelallam, Massimo Tisi
2014 International Conference on Software Technologies: Applications and Foundations  
Scalability is a main obstacle for applying Model-Driven Engineering to reverse engineering, or to any other activity manipulating large models. Existing solutions to persist and query large models are currently inefficient and strongly linked to memory availability. In this paper, we propose a memory unload strategy for Neo4EMF, a persistence layer built on top of the Eclipse Modeling Framework and based on a Neo4j database backend. Our solution allows us to partially unload a model during the
more » ... execution of a query by using a periodical dirty saving mechanism and transparent reloading. Our experiments show that this approach enables to query large models in a restricted amount of memory with an acceptable performance.
dblp:conf/staf/DanielSBT14 fatcat:smumjdn4qjeshjl2wgcxdz4jqy

PrefetchML

Gwendal Daniel, Gerson Sunyé, Jordi Cabot
2016 Proceedings of the ACM/IEEE 19th International Conference on Model Driven Engineering Languages and Systems - MODELS '16  
Prefetching and caching are well-known techniques integrated in database engines and file systems in order to speed-up data access. They have been studied for decades and have proven their efficiency to improve the performance of I/O intensive applications. Existing solutions do not fit well with scalable model persistence frameworks because the prefetcher operates at the data level, ignoring potential optimizations based on the information available at the metamodel level. Furthermore,
more » ... ing components are common in relational databases but typically missing (or rather limited) in NoSQL databases, a common option for model storage nowadays. To overcome this situation we propose PrefetchML, a framework that executes prefetching and caching strategies over models. Our solution embeds a DSL to precisely configure the prefetching rules to follow. Our experiments show that PrefetchML provides a significant execution time speedup. Tool support is fully available online.
doi:10.1145/2976767.2976775 fatcat:ms34hx27tvbjzavpxvt54rmbam
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