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Software Traceability for Multi-Agent Systems Implemented Using BDI Architecture
The development of multi-agent software systems is considered a complex task due to (a) the large number and heterogeneity of documents generated during the development of these systems, (b) the lack of support for the whole development life-cycle by existing agent-oriented methodologies requiring the use of different methodologies, and (c) the possible incompleteness of the documents and models generated during the development of the systems.
In order to alleviate the above problems, in this thesis, a traceability framework is described to support the development of multi-agent systems. The framework supports automatic generation of traceability relations and identification of missing elements (i.e., completeness checking) in the models created during the development life-cycle of multi-agent systems using the Belief-Desire-Intention (BDI) architecture.
Traceability has been recognized as an important activity in the software development process. Traceability relations can guarantee and improve software quality and can help with several tasks such as the evolution of software systems, reuse of parts of the system, validation that a system meets its requirements, understanding of the rationale for certain design decisions, identification of common aspects of the system, and analysis of implications of changes in the
system.
The traceability framework presented in this thesis concentrates on multi-agent software systems developed using i* framework, Prometheus methodology, and JACK language. Here, a traceability reference model is presented for software artefacts generated when using i* framework, Prometheus methodology, and JACK language. Different types of relations between the artefacts are identified. The framework is based on a rule-based approach to support automatic identification of traceability relations and missing elements between the generated artefacts. Software models represented in XML were used to support the heterogeneity of models and tools used during the software development life-cycle. In the framework, the rules are specified in an extension of XQuery to support (i) representation of the consequence part of the rules, i.e. the actions to be taken when the conditions are satisfied, and (ii) extra functions to cover some of the traceability relations being proposed and completeness checking of the models.
A prototype tool has been developed to illustrate and evaluate the work. The work has been evaluated in terms of recall and precision measurements in three different case studies. One small case study of an Automatic Teller Machine application, one medium case study of an Air Traffic Control Environment application, and one large case study of an Electronic Bookstore application
Are metals of antifouling paints transferred to marine biota?
Devido sua alta toxicidade, o TBT está banido desde 2003, o que resultou na re-utilização de tintas a base de cobre. O objetivo deste trabalho é determinar se os metais provenientes das tintas anti-incrustantes (AFP) são transferidos para organismos bentônicos da Baía de Guanabara (BG) (Rio de janeiro, Brasil). Concentrações de metais foram analisadas em duas espécies de algas Ulva flexuosa e U. fasciata e no isópoda, Sphaeroma serratum, em duas áreas de marinas em locais de substrato artificial coberto com tintas AFP e em locais de substrato natural. Também foram coletadas amostras em uma área oceânica (controle). Concentrações de Cd, Cr, Cu, Pb e Zn foram determinadas por Espectrofotometria de Absorção Atômica. Concentrações mais elevadas de Cu, Pb e Zn foram detectadas na BG em ambas espécies de algas em relação a área controle. Dentre as espécies de algas e do isópoda da BG, as populações coletadas sobre as superfícies cobertas com AFP apresentaram concentrações significativamente mais elevadas do que as populações do substrato natural. Os resultados obtidos demonstram que a liberação de metais presentes nas AFP dos decks e embarcações, estão sendo acumulados pelas algas e isópodas. Esses resultados indicam que o revestimento com AFP é a principal fonte de metais para a biota de marinas em áreas da BG.Because of its high toxicity, TBT (trybutiltin) was banned since 2003, which resulted in a greater re-use of Cu as based-biocide in antifouling paints (AFP). The aim of this work is to determine if metals form of AFP are transferred to benthic organisms from Guanabara Bay (GB) (Rio de Janeiro, Brazil). Metal concentrations were measured in two main fouling algae species Ulva flexuosa and U. fasciata and one isopod species, Sphaeroma serratum, in two GB marinas areas from sites with artificial substrate covered by AFP and natural substrate.In addition, control samples were collected in an adjacent open ocean area. Concentrations of Cd, Cr, Cu, Pb and Zn were determined by Atomic Absortion Spectrophotometry. Higher concentrations of Cu, Pb and Zn were detected in both algal species from GB in relation to control areas. Among samples of algae and isopod species from GB, populations collected over artificial surfaces covered by AFP presented significantly higher metal concentration than population of rocky natural substrate. Our data showed that the leaching of metals by antifouling paints present on decks and boats are being taken up by algae and isopods. These results indicate that antifouling coatings are the main source of heavy metal to biota of GB marina area
Seaweed diversity associated with a Brazilian tropical rhodolith bed
This study describes the predominantly tropical, subtidal seaweed populations growing on rhodoliths between 4 and 18 m depth
in the southern part of Espírito Santo State (Brazil). Qualitative and quantitative sampling revealed species-rich algal communities, comprising
167 species. Three species of rhodophytes represent new records for the Brazilian marine flora (Lithothamnion muelleri, Scinaia aborealis, and
Mesophyllum engelhartii). Marked seasonal differences in fleshy algal species composition and abundance were related to seasonal instabilities
caused by winter-storm disturbance over the rhodolith beds. In relation to depth, rhodolith density appears to be an important factor for the
variation in the abundance of fleshy algae. The rhodolith community is composed of at least seven nongeniculate crustose coralline algal
species. Rhodolith beds in southern Espírito Santo State, in an area of 150 km2, provide an important habitat for epibenthic communities,
supporting 25% of the known macroalgal species richness along the Brazilian coast.Web of Scienc
Software traceability for multi-agent systems implemented using BDI architecture
The development of multi-agent software systems is considered a complex task due to (a) the large number and heterogeneity of documents generated during the development of these systems, (b) the lack of support for the whole development life-cycle by existing agent-oriented methodologies requiring the use of different methodologies, and (c) the possible incompleteness of the documents and models generated during the development of the systems. In order to alleviate the above problems, in this thesis, a traceability framework is described to support the development of multi-agent systems. The framework supports automatic generation of traceability relations and identification of missing elements (i.e., completeness checking) in the models created during the development life-cycle of multi-agent systems using the Belief-Desire-Intention (BDI) architecture. Traceability has been recognized as an important activity in the software development process. Traceability relations can guarantee and improve software quality and can help with several tasks such as the evolution of software systems, reuse of parts of the system, validation that a system meets its requirements, understanding of the rationale for certain design decisions, identification of common aspects of the system, and analysis of implications of changes in the system. The traceability framework presented in this thesis concentrates on multi-agent software systems developed using i* framework, Prometheus methodology, and JACK language. Here, a traceability reference model is presented for software artefacts generated when using i* framework, Prometheus methodology, and JACK language. Different types of relations between the artefacts are identified. The framework is based on a rule-based approach to support automatic identification of traceability relations and missing elements between the generated artefacts. Software models represented in XML were used to support the heterogeneity of models and tools used during the software development life-cycle. In the framework, the rules are specified in an extension of XQuery to support (i) representation of the consequence part of the rules, i.e. the actions to be taken when the conditions are satisfied, and (ii) extra functions to cover some of the traceability relations being proposed and completeness checking of the models. A prototype tool has been developed to illustrate and evaluate the work. The work has been evaluated in terms of recall and precision measurements in three different case studies. One small case study of an Automatic Teller Machine application, one medium case study of an Air Traffic Control Environment application, and one large case study of an Electronic Bookstore application.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Rhodoliths and rhodolith beds
Rhodolith (maërl) beds, communities dominated by free living coralline algae, are
a common feature of subtidal environments worldwide. Well preserved as fossils, they have long
been recognized as important carbonate producers and paleoenvironmental indicators. Coralline
algae produce growth bands with a morphology and chemistry that record environmental variation.
Rhodoliths are hard but often fragile, and growth rates are only on the order of mm/yr. The
hard, complex structure of living beds provides habitats for numerous associated species not found
on otherwise entirely sedimentary bottoms. Beds are degraded locally by dredging and other anthropogenic
disturbances, and recovery is slow. They will likely suffer severe impacts worldwide
from the increasing acidity of the ocean. Investigations of rhodolith beds with scuba have enabled
precise stratified sampling that has shown the importance of individual rhodoliths as hot spots of
diversity. Observations, collections, and experiments by divers have revolutionized taxonomic studies
by allowing comprehensive, detailed collection and by showing the large effects of the environment
on rhodolith morphology. Facilitated by in situ collection and calibrations, corallines are now
contributing to paleoclimatic reconstructions over a broad range of temporal and spatial scales.
Beds are particularly abundant in the mesophotic zone of the Brazilian shelf where technical diving
has revealed new associations and species. This paper reviews selected past and present research on
rhodoliths and rhodolith beds that has been greatly facilitated by the use of scuba
First report of Sporolithon ptychoides (Sporolithales, Corallinophycidae, Rhodophyta) for the Atlantic Ocean
Samples corresponding to Sporolithon ptychoides Heydrich were collected in
the mesophotic zone (50 m depth) south of Espírito Santo State, Brazil. The
collected material presented features characteristic of the species namely:
tetrasporangia of 75-105 x 40-55 μm grouped into sori that are raised above the
surrounding vegetative thallus surface; presence of a basal layer of elongate cells
in areas where the tetrasporangia develop; presence of buried tetrasporangial
compartments deep in the thallus; and 3-5 cells in the tetrasporangial
paraphyses. These same features said to collectively characterise S. ptychoides,
were all observed in a representative specimen and the type specimen of
Sporolithon dimotum (Foslie & Howe) Yamaguishi-Tomita ex M.J Wynne.
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This latter species is thus conspecific with S. ptychoides and is therefore
considered a heterotypic synonym thereof as S. ptychoides has nomenclatural
priority. This study expands the known geographical distribution of the species
and may give insight into the origin of the species into other geographical
regions.Web of Scienc
Rhodolith bed structure along a depth gradient on the northern coast of bahia state, brazil
O objetivo deste estudo foi determinar a estrutura de um banco de rodolitos ao longo de um gradiente de profundidade na plataforma em frente à cidade de Salvador, nordeste brasileiro. Foram analisadas as dimensões, a forma e composição das algas calcárias dos rodolitos, bem como a vitalidade, densidade e flora associada ao banco, em três profundidades: 5, 15 e 25 m. As amostras foram obtidas por meio de mergulho autônomo no verão de 2007. Cinco espécies de algas calcárias formadoras de rodolito foram identificadas: Sporolithon episporum, Lithothamnion brasiliense, Lithothamnion superpositum, Mesophyllum erubescens e Lithophyllum sp. A forma de crescimento incrustante e a forma esférica foram predominantes em todas as profundidades. Houve uma redução da dimensão e vitalidade dos rodolitos e um aumento da densidade com a profundidade. Cinqüenta e seis espécies de macroalgas foram encontradas como flora associada aos rodolitos. A profundidade mais rasa apresentou os maiores valores de biomassa e número de espécies de macroalgas. Esses resultados, associados com outras descrições recentes de bancos de rodolitos, indicam que o padrão estrutural desses bancos no Brasil, ao longo de gradientes de profundidade, pode estar relacionado a uma combinação da extensão e da inclinação da plataforma continental.The aim of this study was to determine the structure of a rhodolith bed along a depth gradient of 5 to 25 m in the shelf in front of Salvador City, a region of northeastern Brazil. The dimensions, morphology and coralline algae composition of the rhodoliths were analyzed, as well as the vitality, density, and associated flora of the bed at three depths: 5, 15 and 25 m. Samples were obtained by SCUBA divers in summer 2007. Five rhodolith-forming taxa were identified: Sporolithon episporum, Lithothamnion brasiliense, Lithothamnion superpositum, Mesophyllum erubescens, and Lithophyllum sp. The encrusting growth form and the spherical shape were predominant at all depths. Rhodolith dimensions and vitality decreased and the density increased from the shallow to the deepest zones. Fifty-six macroalgal species were found as rhodolith-associated flora. The shallower depth presented higher values for macroalgal biomass and number of species. These results associated with other recent rhodolith bed descriptions indicate that the pattern of Brazilian rhodolith bed structure along depth gradients may be related to a combination of the extent and slope of the continental shelf
MACROFORAMINÍFEROS EM RODOLITOS NA CADEIA VITÓRIA-TRINDADE, ATLÂNTICO SUL, MARGEM LESTE BRASILEIRA
A Cadeia Vitória-Trindade tem 1150 km de extensão contendo 11 montes submarinos, no sentido L-W, na margem leste brasileira, entre as coordenadas de 20-21º S e 29-38º W. No topo destes montes se desenvolvem bancos de rodolitos, formados por algas coralíneas (Rhodophyta). O Brasil possui uma grande área de rodolitos, pouco explorada, sendo pioneiro o estudo dos foraminíferos. Existem em abundância, com grandes exemplares e ótima preservação. Os rodolitos foram coletados em 2011 por mergulhadores, em pontos localizados nos cumes dos montes da cadeia a aproximadamente 60m de profundidade, nas ilhas Vitória e Almirante Saldanha. Após a preparação das amostras, foram triadas aleatoriamente 300 tecas de foraminíferos da fração maior que 500µm, da epifauna e da criptofauna, respectivamente. Foi realizada a classificação e a sistemática das espécies com algumas descrições, considerando-se o ineditismo do material. Análises quantitativas incluíram apenas a abundância absoluta e relativa. Espécies típicas de ambientes recifais, tais como Amphistegina gibbosa, Archaias angulatus e Discogypsina vesicularis foram abundantes. Os indivíduos possuem em geral grande tamanho, paredes grossas e ótimo estado de preservação. Sua classificação taxonômica leva à identificação de possíveis novas espécies ainda não encontradas nos recifes brasileiros e, provavelmente, ainda não descritas
The influence of brown algae alginates on phenolic compounds capability of ultraviolet radiation absorption in vitro
Os compostos fenólicos (PC) de algas pardas são metabólitos secundários que participam de diversos processos biológicos, como proteção contra radiação ultravioleta (UV), bloqueio de poliespermia e ligação de metais. Recentemente, os PC têm sido estudados devido a possíveis interações com polissacarídeos da parede celular. Entretanto, existem poucas evidências sobre estas interações e sua influência em processos fisiológicos. Neste trabalho, foram investigadas as interações entre os PC de Padina gymnospora e os alginatos e a influência destas interações na capacidade de absorção de UV pelos PC. Foram utilizadas técnicas cromatográficas e espectrofotométricas para o isolamento, a caracterização e a determinação da capacidade de absorção de UV dos compostos estudados. Mesmo após a extração dos polissacarídeos de P. gymnospora e a utilização dos métodos de isolamento, os PC permaneceram ligados ao alginato. A interação de alginato com PC não causou modificações no padrão de absorção do espectro eletromagnético (UV-VIS-IR). A capacidade de absorção de UV dos PC ligados aos alginatos foi mantida por um tempo mais longo do que a do extrato de PC puros. Os resultados obtidos demonstram que há uma forte ligação entre PC e alginatos e que estas ligações preservam a capacidade de absorção de UV dos PC ao longo do tempo.Brown algae phenolic compounds (PC) are secondary metabolites that participate in many biological processes, such as ultraviolet radiation (UV) protection, polyspermy blocking and trace metals bounding. Recently, PC has also been studied due to possible interactions with cell wall polysaccharides. However, there are few evidences of these interactions and their influence in physiological processes. The interactions between PC from the brown alga Padina gymnospora and alginates and the influence of these interactions on the UV absorption properties of PC were investigated in this work. Chromatography and spectrophotometry techniques were used to isolate, characterize and determine UV absorption capacity of studied compounds. Even after the P. gymnospora polysaccharide extraction and isolating methods, the PC was maintained linked to the alginate. The interaction of alginates with PC did not cause modifications on absorbance pattern of electromagnetic spectrum (UV-VIS-IR). The UV absorbance capability of PC linked to alginate was maintained for a longer period of time if compared with the purified PC. The obtained results reveal the strong linkage between PC and alginates and that these linkages preserve the UV absorption capability of PC along time
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