SCoRe: a Self-Organizing Multi-Agent System for Decision Making in Dynamic Software Developement Processes

International audienceSoftware systems are becoming more and more complex. A common dilemma faced by software engineers in building complex systems is the lack of method adaptability. However, existing agent-based methodologies and tools are developed for particular system and are not tailored for new problems. This paper proposes an architecture of a new tool based on SME for self-constructing customized method processes. Our approach is based on two pillars: the process fragment and the MAS meta-model. These two elements are both defined and considered under a specific agent-oriented perspective thus creating a peculiar approach. Our work is based on the self-organization of agents, making it especially suited to deal with highly dynamic systems such as the design of an interactive and adaptive software engineering process

SCoRe: a Self-Organizing Multi-Agent System for Decision Making in Dynamic Software Developement Processes

Software systems are becoming more and more complex. A common dilemma faced by software engineers in building complex systems is the lack of method adaptability. However, existing agent-based methodologies and tools are developed for particular system and are not tailored for new problems. This paper proposes an architecture of a new tool based on SME for self-constructing customized method processes. Our approach is based on two pillars: the process fragment and the MAS meta-model. These two elements are both defined and considered under a specific agent-oriented perspective thus creating a peculiar approach. Our work is based on the self-organization of agents, making it especially suited to deal with highly dynamic systems such as the design of an interactive and adaptive software engineering process

Forward Self-Combined Method Fragments

International audienceDeveloping complex systems is generally simplified if designer is guided by method from Software Engineering. However a single engineering process is often not enough to cover all the possible requirements due to different levels of expertise and systems to design. Currently, Agent Oriented Software Engineering methods aim at providing an adaptive engineering process. The method processes have been broken up into different parts called fragments, enabling the mix of different engineering processes’ parts to get better adequacy between the system to be done and the process. But some difficulties still remain concerning the expertise needed to compose these fragments when the amount of fragments prevents the composition to be done by hand. This paper presents an Adaptive Multi-Agent Systems (AMAS) to deal with a new paradigm of automated fragments combining. This process is made from both the characteristics of users and system and the known fragments. Thanks to their information, agents of the AMAS self-organise and design a tailored method process. The developed system is described and then usual tests are depicted

ADELFE 2.0

International audienceADELFE is a French acronym that means “Toolkit for Designing Software with Emergent Functionalities” (“Atelier de DEveloppement de Logiciels à Fonctionnalité Emergente” in French). ADELFE methodology is dedicated to applications characterized by openness and the need of the system adaptation to an environment. Its main goal is to help and guide any designer during the development of an Adaptive Multi-agent System (AMAS). An AMAS is characterized by the following points: it is plunged into an environment and composed of interdependent agents, each agent carries out a partial function and the agents, organization during runtime makes the system realize an emergent function. Actually, an agent is locally cooperative, i.e. it is able to recognize cooperation failures called Non-cooperative Situations (NCS, which could be related to exceptions in classical programs) and treat them. ADELFE includes five Work Definitions that were initially inspired from the Rational Unified Process (RUP) and gathers 21 activities, producing or refining 12 work products. These products are aggregating modelling diagrams or structured or free text. ADELFE, which is a Model-Driven (model-centred) development method, is not hardly dependent on Domain Specific Modelling Languages (DSML) but currently the recommendation is to use UML2 for general activities and to use AMASML (AMAS Modelling Language) and SpeADL (Species-based Modelling Language) for specific activities appearing in Analysis, Design or Implementation phases

Introduction bias affects relationships between the characteristics of ornamental alien plants and their naturalization success

Aim:Alien plants with certain characteristics may have been introduced earlier and more frequently than others. Such introduction bias may cause spurious associations between plant characteristics and naturalization (the establishment of self-sustaining populations in the wild). We aimed to disentangle direct and indirect (i.e. mediated by introduction history) effects of species characteristics on the naturalization success of alien plants introduced for horticulture.Location:Germany (non-native range); rest of the world (native range).Methods:We compiled a dataset of 435 alien plant species introduced in cultivation in Germany, including data on their year of introduction, the number of botanical gardens where they are planted, native range, biological traits and naturalization success. We used path analysis to estimate the direct effects of geographical origin and biological traits on naturalization, and their indirect effects mediated by year and/or frequency of introduction.Results:We found significant direct positive effects of native range size and winter hardiness on naturalization. Alien species native to other parts of Europe and species with a large native range were brought to the country earlier than other species. In addition, woody species, winter-hardy species and tall species were planted more frequently than others. Because the number of botanical gardens where a species is planted increased naturalization success directly, and residence time did so indirectly through a significant positive association with the number of botanical gardens, most of the species characteristics had indirect effects on naturalization.Main conclusions:Our approach allowed us to show that apparent effects of species characteristics on naturalization success can be at least partly indirect, due to introduction biases. This indicates that failure to recognize such introduction biases could impair our ability to explain the success of alien plant species.publishe

Introduction history, climatic suitability, native range size, species traits and their interactions explain establishment of Chinese woody species in Europe

Aim:A major challenge in ecology is to understand how multiple causal factors, which may interact, drive success of non-native plants in new ranges. In this study we addressed the role of introduction history, climatic suitability, native range size, species traits and their interactions in the establishment of Chinese woody species in Europe.Location:China (native range), Europe (new range).Methods:We tested whether establishment of 449 Chinese woody species in Europe was associated with residence time (time since earliest planting), planting frequency, climatic suitability, native range size and species traits. We also considered possible nonlinear effects and interactions among these variables. For the 38 species that have established in Europe, we further tested whether these variables and interactions explained their establishment in multiple European countries.Results:Establishment of the 449 species in Europe was positively associated with residence time, planting frequency and climatic suitability. Except residence time, these factors were also positively associated with establishment of the 38 species in multiple countries. None of the traits tested had statistically significant main effects on establishment in Europe, but, for the established species, longer flowering period and having compound leaves were positively associated with establishment in multiple countries. The positive association between establishment in Europe and residence time was stronger for evergreen than for deciduous species. In addition, evergreens, unlike deciduous species, showed a positive association between establishment in Europe and fruiting duration. Moreover, establishment in multiple countries was positively associated with planting frequency for species with compound leaves but not for species with simple leaves, and the association between the establishment and fruiting duration changed from negative to moderately positive as climatic suitability increased.Main conclusions:Introduction history and climatic suitability explain most of the variation in establishment, and modulate the role of species traits, such as leaf retention, leaf type and fruiting duration.publishe

Introduction history, climatic suitability, native range size, species traits and their interactions explain establishment of Chinese woody species in Europe

AimA major challenge in ecology is to understand how multiple causal factors, which may interact, drive success of non-native plants in new ranges. In this study we addressed the role of introduction history, climatic suitability, native range size, species traits and their interactions in the establishment of Chinese woody species in Europe. LocationChina (native range), Europe (new range). MethodsWe tested whether establishment of 449 Chinese woody species in Europe was associated with residence time (time since earliest planting), planting frequency, climatic suitability, native range size and species traits. We also considered possible nonlinear effects and interactions among these variables. For the 38 species that have established in Europe, we further tested whether these variables and interactions explained their establishment in multiple European countries. ResultsEstablishment of the 449 species in Europe was positively associated with residence time, planting frequency and climatic suitability. Except residence time, these factors were also positively associated with establishment of the 38 species in multiple countries. None of the traits tested had statistically significant main effects on establishment in Europe, but, for the established species, longer flowering period and having compound leaves were positively associated with establishment in multiple countries. The positive association between establishment in Europe and residence time was stronger for evergreen than for deciduous species. In addition, evergreens, unlike deciduous species, showed a positive association between establishment in Europe and fruiting duration. Moreover, establishment in multiple countries was positively associated with planting frequency for species with compound leaves but not for species with simple leaves, and the association between the establishment and fruiting duration changed from negative to moderately positive as climatic suitability increased. Main conclusionsIntroduction history and climatic suitability explain most of the variation in establishment, and modulate the role of species traits, such as leaf retention, leaf type and fruiting duration.China Scholarship Council (CSC); DFG [KL 1866/5-1]SCI(E)[email protected]

Naturalizovaná nepůvodní flóra světa: druhová diverzita, taxonomické a fylogenetické složení, geografické zákonitosti a globální ohniska rostlinných invazí

Using the recently built Global Naturalized Alien Flora (GloNAF) database, containing data on the distribution of naturalized alien plants in 483 mainland and 361 island regions of the world, we describe patterns in diversity and geographic distribution of naturalized and invasive plant species, taxonomic, phylogenetic and life-history structure of the global naturalized flora as well 204 Preslia 89: 203–274, 2017 as levels of naturalization and their determinants. The mainland regions with the highest numbers of naturalized aliens are some Australian states (with New South Wales being the richest on this continent) and several North American regions (of which California with 1753 naturalized plant species represents the world’s richest region in terms of naturalized alien vascular plants). England, Japan, New Zealand and the Hawaiian archipelago harbour most naturalized plants among islands or island groups. These regions also form the main hotspots of the regional levels of naturalization, measured as the percentage of naturalized aliens in the total flora of the region. Such hotspots of relative naturalized species richness appear on both the western and eastern coasts of North America, in north-western Europe, South Africa, south-eastern Australia, New Zealand, and India. High levels of island invasions by naturalized plants are concentrated in the Pacific, but also occur on individual islands across all oceans. The numbers of naturalized species are closely correlated with those of native species, with a stronger correlation and steeper increase for islands than mainland regions, indicating a greater vulnerability of islands to invasion by species that become successfully naturalized. South Africa, India, California, Cuba, Florida, Queensland and Japan have the highest numbers of invasive species. Regions in temperate and tropical zonobiomes harbour in total 9036 and 6774 naturalized species, respectively, followed by 3280 species naturalized in the Mediterranean zonobiome, 3057 in the subtropical zonobiome and 321 in the Arctic. The NewWorld is richer in naturalized alien plants, with 9905 species compared to 7923 recorded in the Old World. While isolation is the key factor driving the level of naturalization on islands, zonobiomes differing in climatic regimes, and socioeconomy represented by per capita GDP, are central for mainland regions. The 11 most widely distributed species each occur in regions covering about one third of the globe or more in terms of the number of regions where they are naturalized and at least 35% of the Earth’s land surface in terms of those regions’ areas, with the most widely distributed species Sonchus oleraceus occuring in 48% of the regions that cover 42% of the world area. Other widely distributed species are Ricinus communis, Oxalis corniculata, Portulaca oleracea, Eleusine indica, Chenopodium album, Capsella bursa-pastoris, Stellaria media, Bidens pilosa, Datura stramonium and Echinochloa crus-galli. Using the occurrence as invasive rather than only naturalized yields a different ranking, with Lantana camara (120 regions out of 349 for which data on invasive status are known), Calotropis procera (118), Eichhornia crassipes (113), Sonchus oleraceus (108) and Leucaena leucocephala (103) on top. As to the life-history spectra, islands harbour more naturalized woody species (34.4%) thanmainland regions (29.5%), and fewer annual herbs (18.7% compared to 22.3%). Ranking families by their absolute numbers of naturalized species reveals that Compositae (1343 species), Poaceae (1267) and Leguminosae (1189) contribute most to the global naturalized alien flora. Some families are disproportionally represented by naturalized aliens on islands (Arecaceae, Araceae, Acanthaceae, Amaryllidaceae, Asparagaceae, Convolvulaceae, Rubiaceae, Malvaceae), and much fewer so on mainland (e.g. Brassicaceae, Caryophyllaceae, Boraginaceae). Relating the numbers of naturalized species in a family to its total global richness shows that some of the large species-rich families are over-represented among naturalized aliens (e.g. Poaceae, Leguminosae, Rosaceae, Amaranthaceae, Pinaceae), some under-represented (e.g. Euphorbiaceae, Rubiaceae), whereas the one richest in naturalized species, Compositae, reaches a value expected from its global species richness. Significant phylogenetic signal indicates that families with an increased potential of their species to naturalize are not distributed randomly on the evolutionary tree. Solanum (112 species), Euphorbia (108) and Carex (106) are the genera richest in terms of naturalized species; over-represented on islands are Cotoneaster, Juncus, Eucalyptus, Salix, Hypericum, Geranium and Persicaria, while those relatively richer in naturalized species on the mainland are Atriplex, Opuntia, Oenothera, Artemisia, Vicia, Galium and Rosa. The data presented in this paper also point to where information is lacking and set priorities for future data collection. The GloNAF database has potential for designing concerted action to fill such data gaps, and provide a basis for allocating resources most efficiently towards better understanding and management of plant invasions worldwide.publishe

The role of adaptive strategies in plant naturalization

Determining the factors associated with the naturalization of alien species is a central theme in ecology. Here, we tested the usefulness of a metric for quantifying Grime’s seminal concept of adaptive strategies – competitors, stress-tolerators and ruderals (CSR) – to explain plant naturalizations worldwide. Using a global dataset of 3004 vascular plant species, and accounting for phylogenetic relatedness and species’ native biomes, we assessed the associations between calculated C-, S- and R-scores and naturalization success for species exhibiting different life forms. Across different plant life forms, C-scores were positively and S-scores negatively associated with both the probability of naturalization and the number of regions where the species has naturalized. Rscores had positive effects on the probability of naturalization. These effects of the scores were, however, weak to absent for tree species. Our findings demonstrate the utility of CSR-score calculation to broadly represent, and potentially explain, the naturalization success of plant species.publishe