Hierarchies of Weighted Closed Partially-Ordered Patterns for Enhancing Sequential Data Analysis

International audienceDiscovering sequential patterns in sequence databases is an important data mining task. Recently, hierarchies of closed partially-ordered patterns (cpo-patterns), built directly using Relational Concept Analysis (RCA), have been proposed to simplify the interpretation step by highlighting how cpo-patterns relate to each other. However, there are practical cases (e.g. choosing interesting navigation paths in the obtained hierarchies) when these hierarchies are still insufficient for the expert. To address these cases, we propose to extract hierarchies of more informative cpo-patterns, namely weighted cpo-patterns (wcpo-patterns), by extending the RCA-based approach. These wcpo-patterns capture and explicitly show not only the order on itemsets but also their different influence on the analysed sequences. We illustrate how the proposed wcpo-patterns can enhance sequential data analysis on a toy example

RCA-Seq: an Original Approach for Enhancing the Analysis of Sequential Data Based on Hierarchies of Multilevel Closed Partially-Ordered Patterns

International audienceMethods for analysing sequential data generally produce a huge number of sequential patterns that have then to be evaluated and interpreted by domain experts. To diminish this number and thus the difficulty of the interpretation task, methods that directly extract a more compact representation of sequential patterns, namely closed partially-ordered patterns (CPO-patterns), were introduced. In spite of the fewer number of obtained CPO-patterns, their analysis is still a challenging task for experts since they are unorgan-ised and besides, do not provide a global view of the discovered regularities. To address these problems, we present and formalise an original approach within the framework of Relational Concept Analysis (RCA), referred to as RCA-Seq, that focuses on facilitating the interpretation task of experts. The hierarchical RCA result allows to directly obtain and organize the relationships between the extracted CPO-patterns. Moreover, a generalisation order on items is also revealed, and multilevel CPO-patterns are obtained. Therefore, a hierarchy of such CPO-patterns guides the interpretation task, helps experts in better understanding the extracted patterns, and minimises the chance of overlooking interesting CPO-patterns. RCA-Seq is compared with another approach that relies on pattern structures. In addition, we highlight the adaptability of RCA-Seq by integrating a user-defined tax-* onomy over the items, and by considering user-specified constraints on the order relations on itemsets

An intelligent system to ensure interoperability for the dairy farm business model

Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Picking reliable partners, negotiating synchronously with all partners, and managing similar proposals are challenging tasks for any manager. This challenge is even harder when it concerns small and medium enterprises (SMEs) who need to deal with short budgets and evident size limitations, often leading them to avoid handling very large contracts. This size problem can only be mitigated by collaboration efforts between multiple SMEs, but then again this brings back the initially stated issues. To address these problems, this paper proposes a collaborative negotiation system that automates the outsourcing part by assisting the manager throughout a negotiation. The described system provides a comprehensive view of all negotiations, facilitates simultaneous bilateral negotiations, and provides support for ensuring interoperability among multiple partners negotiating on a task described by multiple attributes. In addition, it relies on an ontology to cope with the challenges of semantic interoperability, it automates the selection of reliable partners by using a lattice-based approach, and it manages similar proposals by allowing domain experts to define a satisfaction degree for each SME. To showcase this method, this research focused on small and medium-size dairy farms (DFs) and describes a negotiation scenario in which a few DFs are able to assess and generate proposals.publishersversionpublishe

The structure and dynamics of commercial catches from inland waters of Romania in 2008-2018

Romania's hydrographic network is 843710 ha, which represents over 3.5% of the total area of the country. In this paper are presented the quantitative and qualitative structure of the commercial fish catches in the inland waters of Romania during the period 2008 - 2018. The natural water basins constituting the national public domain and in which legal fishing takes place are: Danube, Danube Delta, the complex lake Razim - Sinoie, reservoirs, Prut and Siret. The processed data come from data reported by economic agents authorized to practice the commercial fishing to the National Agency for Fisheries and Aquaculture. The catches recorded in continental waters from our country during the 2080 - 2018 period varied as follows: the smallest quantity was registered in 2010 (2457 tonnes) and the largest quantity was recorded in 2016 (3868.51 tonnes). The main species captured in Romania's inland waters in the 2008 - 2018 period were the following: prussian carp (41.74%), freshwater bream (11.66%), pontic shad (10.53%), roach (6.77%), carp (5.46%), wels catfish (5.01%), pike-perch (4.28%), northern pike (3.88%)

Evaluation of organic pollution by palmer's algal index of salt lake, Braila county

The present study was conducted to assess the organic pollution level of Sarat Lake in the city of Braila. A total of 14 species belonging to 12 genera of phytoplankton have been identified, among them 9 species belong to Bacillariophyceae, 2 species of Cholorophyceae and 3 species of Cyanophyceae. The Palmer, Algal Genus and Algal Species Pollution Index were employed to study the water quality of Sarat Lake in the city of Braila. Palmer's Algal Index showed that all four stations in Sarat Lake have little organic pollution. The total scores in S1 and S4 were 11 indicating moderate pollution, in S2 and S3 were 9 indicating lack of organic pollution. The genera with tolerance to pollution were Oscillatoria, Phormidium, Synedra and Navicula. Physical-chemical analysis data has supported Palmer's organic pollution index. Shannon Wiener index was recorded as a diversity index, it recorded the maximum value (3,311) in S4 and the minimum value (2,774) in S2. Thus, algae taxa can be considered a good bioindicator for assessing the health of lentic aquatic ecosystems

Proyecto Latin@ on stage and under the magnifying glass: The possibilities and limitations of a high-profile institutionally sponsored youth participatory action research project

While many educators committed to critical pedagogy must find ways to do their work “off the grid and under the radar,” there are instances in which conditions allow for projects to be implemented with institutional supports and resources. While these conditions are unusual, it is important to understand both the possibilities and limitations of such opportunities and to consider what they teach us both about critical pedagogical approaches as well as the educational institutions within which we work. In this article, we turn the spotlight on “Proyecto Latin@”, a collaborative project implemented under the auspices of the University of Toronto and the Toronto District School Board. This partnership, particularly with respect to the YPAR phase of this unique study, has engendered much public attention as well as institutional, community, and public scrutiny. Using the key tenets of YPAR as our theoretical framework, we provide a general overview of our work with Latin@ students, which was implemented as a senior social science credit course. We discuss some of the tensions that arise in doing YPAR under such institutional constraints, and take up the challenges and possibilities of conducting research with, by, and for youths while “on stage and under the magnifying glass.” Particular challenges that we will discuss include: public expectations, community and media perceptions, negotiations of our roles as project co-facilitators, and the tensions that arise when attempting to embody the youth-centred principles of YPAR while delivering a senior social science credit course

High-level dietary cadmium exposure is associated with global DNA hypermethylation in the gastropod hepatopancreas

5-methylcytosine (5mC) is a key epigenetic mark which influences gene expression and phenotype. In vertebrates, this epigenetic mark is sensitive to Cd exposure, but there is no information linking such an event with changes in global 5mC levels in terrestrial gastropods despite their importance as excellent ecotoxicological bioindicators of metal contamination. Therefore, we first evaluated total 5mC content in DNA of the hepatopancreas of adult Cantareus aspersus with the aim to determine whether this epigenetic mark is responsive to Cd exposure. The experiment was conducted under laboratory conditions and involved a continuous exposure, multiple dose- and time-point (14, 28, and 56 days) study design. Hepatopancreas cadmium levels were measured using Flame Atomic Absorption Spectrometry and the percentage of 5-mC in samples using an ELISA-based colorimetric assay. Snail death rates were also assessed. Our results, for the first time, reveal the presence of 5mC in C. aspersus and provide evidence for Cd-induced changes in global 5mC levels in DNA of gastropods and mollusks. Although less sensitive than tissue accumulation, DNA methylation levels responded in a dose- and time-dependent manner to dietary cadmium, with exposure dose having a much stronger effect than exposure duration. An obvious trend of increasing 5mC levels was observed starting at 28 days of exposure to the second highest dose and this trend persisted at the two highest treatments for close to one month, when the experiment was terminated after 56 days. Moreover, a strong association was identified between Cd concentrations in the hepatopancreas and DNA methylation levels in this organ. These data indicate an overall trend towards DNA hypermethylation with elevated Cd exposure. No consistent lethal effect was observed, irrespective of time point and Cd-dosage. Overall, our findings suggest that the total 5mC content in DNA of the hepatopancreas of land snails is responsive to sublethal Cd exposure and give new insights into invertebrate environmental epigenetics

A lattice-based query system for assessing the quality of hydro-ecosystems

International audienceConcept lattices are useful tools for organising and querying data. In this paper we present an application of lattices for analysing and classifying stream sites described by physical, physico-chemical and biological parameters. Lattices are first used for building a hierarchy of site profiles which are annotated by hydro-ecologists. This hierarchy can then be queried to classify and assess new sites. The whole approach relies on an information system storing data about Alsatian stream sites and their parameters. A specific interface has been designed to manipulate the lattices and an incremental algorithm has been implemented to perform the query operations

L’analyse relationnelle de concepts pour la fouille de données temporelles – Application à l’étude de données hydroécologiques

National audienceCet article présente une méthode d'exploration de données temporelles, fondée sur l'analyse relationnelle de concepts (ARC) et appliquée à des données séquentielles construites à partir d'échantillons physico-chimiques et biologiques prélevés dans des cours d'eau. Notre but est de mettre au jour des sous-séquences pertinentes et hiérarchisées, associant les deux types de paramètres. Pour faciliter la lecture, ces sous-séquences sont représentées sous la forme de motifs partiellement ordonnés (po-motifs). Le processus de fouille de données se décompose en plusieurs étapes : construction d'un modèle temporel ad hoc et mise en oeuvre de l'ARC ; extraction des sous-séquences synthétisées sous la forme de po-motifs ; sélection des po-motifs intéressants grâce à une mesure exploitant la distribution des extensions de concepts. Le processus a été testé sur un jeu de données réelles et évalué quantitativement et qualitativement

Indoor Hibernation of <em>Helix aspersa</em> Juveniles

The “Italian” outdoor snailfarming technology assumes that both mature and juvenile snails hibernate outdoor, protected by a thin sheet of unweaved coverlet (agryl sheet). In contrast, the “French” snailfarming technology implies that only mature brown garden snails (Helix aspersa) hibernate indoor, in strictly controlled microenvironmental parameters (temperature, humidity, and ventilation). This technology may also be viable for H. aspersa juveniles. Extremely high death rates occurring in Romanian outdoor snailfarms during colder winters (>80%) imposed the need to find alternative paths for a proper hibernation of H. aspersa. Using statistical analyses, close surveillance of technological flow, and controlled microenvironmental parameters, we assessed the possibility to adapt indoor hibernation for H. aspersa juveniles. The experiments lasted for 2 years (2006–2008) and were carried out on 34,000 H. aspersa juveniles and 15,000 mature ones, using different technological flows and microenvironmental parameters (temperature, humidity, and ventilation). They were performed in two stages and involved five case studies, conducted independently in three different locations: Floreşti (Mehedinţi county), Sântuhalm (Hunedoara county), and Muntenii de Sus (Vaslui county). The first stage tested the hypothesis in relation to survival rate of mature snails, H. aspersa, in the same conditions, whereas the second stage improved the technological flow, before its extensive application. We demonstrated that noncontrolled microclimate parameters (temperature, humidity, and ventilation) and the use of straw as hibernation support induced significant differences (P < 0.01) concerning death levels of H. aspersa juveniles as compared to their indoor hibernation in semicontrolled microclimate (temperature and ventilation). In the same hibernation microclimate, mature snails exhibited higher survival levels than the juvenile ones, irrespective of technological flow and origin (P < 0.0001). We also demonstrated that juveniles’ weight loss displays a relatively constant variation (16.33–20.51%). In addition, the correlations between the individual average weight before and after hibernation were described by the same logarithmic regression. Furthermore, significantly higher survival rates of H. aspersa juveniles (P < 0.0001) have been registered when they had not been awakened during hibernation. Finally, we proved that indoor hibernation of H. aspersa juveniles in strictly controlled microenvironmental parameters (temperature, humidity, and ventilation) could represent a viable technology that improves the technological flow in outdoor snailfarming during wintertime in colder climates