969 resultados para Complex Processes


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Autonomous vehicles are increasingly being used in mission-critical applications, and robust methods are needed for controlling these inherently unreliable and complex systems. This thesis advocates the use of model-based programming, which allows mission designers to program autonomous missions at the level of a coach or wing commander. To support such a system, this thesis presents the Spock generative planner. To generate plans, Spock must be able to piece together vehicle commands and team tactics that have a complex behavior represented by concurrent processes. This is in contrast to traditional planners, whose operators represent simple atomic or durative actions. Spock represents operators using the RMPL language, which describes behaviors using parallel and sequential compositions of state and activity episodes. RMPL is useful for controlling mobile autonomous missions because it allows mission designers to quickly encode expressive activity models using object-oriented design methods and an intuitive set of activity combinators. Spock also is significant in that it uniformly represents operators and plan-space processes in terms of Temporal Plan Networks, which support temporal flexibility for robust plan execution. Finally, Spock is implemented as a forward progression optimal planner that walks monotonically forward through plan processes, closing any open conditions and resolving any conflicts. This thesis describes the Spock algorithm in detail, along with example problems and test results.

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Over the last 60 years, computers and software have favoured incredible advancements in every field. Nowadays, however, these systems are so complicated that it is difficult – if not challenging – to understand whether they meet some requirement or are able to show some desired behaviour or property. This dissertation introduces a Just-In-Time (JIT) a posteriori approach to perform the conformance check to identify any deviation from the desired behaviour as soon as possible, and possibly apply some corrections. The declarative framework that implements our approach – entirely developed on the promising open source forward-chaining Production Rule System (PRS) named Drools – consists of three components: 1. a monitoring module based on a novel, efficient implementation of Event Calculus (EC), 2. a general purpose hybrid reasoning module (the first of its genre) merging temporal, semantic, fuzzy and rule-based reasoning, 3. a logic formalism based on the concept of expectations introducing Event-Condition-Expectation rules (ECE-rules) to assess the global conformance of a system. The framework is also accompanied by an optional module that provides Probabilistic Inductive Logic Programming (PILP). By shifting the conformance check from after execution to just in time, this approach combines the advantages of many a posteriori and a priori methods proposed in literature. Quite remarkably, if the corrective actions are explicitly given, the reactive nature of this methodology allows to reconcile any deviations from the desired behaviour as soon as it is detected. In conclusion, the proposed methodology brings some advancements to solve the problem of the conformance checking, helping to fill the gap between humans and the increasingly complex technology.

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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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There is now an emerging need for an efficient modeling strategy to develop a new generation of monitoring systems. One method of approaching the modeling of complex processes is to obtain a global model. It should be able to capture the basic or general behavior of the system, by means of a linear or quadratic regression, and then superimpose a local model on it that can capture the localized nonlinearities of the system. In this paper, a novel method based on a hybrid incremental modeling approach is designed and applied for tool wear detection in turning processes. It involves a two-step iterative process that combines a global model with a local model to take advantage of their underlying, complementary capacities. Thus, the first step constructs a global model using a least squares regression. A local model using the fuzzy k-nearest-neighbors smoothing algorithm is obtained in the second step. A comparative study then demonstrates that the hybrid incremental model provides better error-based performance indices for detecting tool wear than a transductive neurofuzzy model and an inductive neurofuzzy model.

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With advances in the synthesis and design of chemical processes there is an increasing need for more complex mathematical models with which to screen the alternatives that constitute accurate and reliable process models. Despite the wide availability of sophisticated tools for simulation, optimization and synthesis of chemical processes, the user is frequently interested in using the ‘best available model’. However, in practice, these models are usually little more than a black box with a rigid input–output structure. In this paper we propose to tackle all these models using generalized disjunctive programming to capture the numerical characteristics of each model (in equation form, modular, noisy, etc.) and to deal with each of them according to their individual characteristics. The result is a hybrid modular–equation based approach that allows synthesizing complex processes using different models in a robust and reliable way. The capabilities of the proposed approach are discussed with a case study: the design of a utility system power plant that has been decomposed into its constitutive elements, each treated differently numerically. And finally, numerical results and conclusions are presented.

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Supply chains comprise of complex processes spanning across multiple trading partners. The various operations involved generate large number of events that need to be integrated in order to enable internal and external traceability. Further, provenance of artifacts and agents involved in the supply chain operations is now a key traceability requirement. In this paper we propose a Semantic web/Linked data powered framework for the event based representation and analysis of supply chain activities governed by the EPCIS specification. We specifically show how a new EPCIS event type called "Transformation Event" can be semantically annotated using EEM - The EPCIS Event Model to generate linked data, that can be exploited for internal event based traceability in supply chains involving transformation of products. For integrating provenance with traceability, we propose a mapping from EEM to PROV-O. We exemplify our approach on an abstraction of the production processes that are part of the wine supply chain.

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Oligodendrocytes and Schwann cells are engaged in myelin production, maintenance and repairing respectively in the central nervous system (CNS) and the peripheral nervous system (PNS). Whereas oligodendrocytes act only within the CNS, Schwann cells are able to invade the CNS in order to make new myelin sheaths around demyelinated axons. Both cells have some limitations in their activities, i.e. oligodendrocytes are post-mitotic cells and Schwann cells only get into the CNS in the absence of astrocytes. Ethidium bromide (EB) is a gliotoxic chemical that when injected locally within the CNS, induce demyelination. In the EB model of demyelination, glial cells are destroyed early after intoxication and Schwann cells are free to approach the naked central axons. In normal Wistar rats, regeneration of lost myelin sheaths can be achieved as early as thirteen days after intoxication; in Wistar rats immunosuppressed with cyclophosphamide the process is delayed and in rats administered cyclosporine it may be accelerated. Aiming the enlightening of those complex processes, all events concerning the myelinating cells in an experimental model are herein presented and discussed.

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Este texto trata do tema da pesquisa "com" o cotidiano. O interesse é provocar uma permanente abertura para a reflexão e o debate sobre o cotidiano e a pesquisa com o cotidiano, e não fechar a questão com uma proposta sistemática. Vale-se dos estudos desenvolvidos em escolas públicas do Estado do Espírito Santo no período de 1999 a 2004, cujo principal objetivo foi desencadear, entre os praticantes do cotidiano escolar, práticas de intervenção nos "currículos" e na "formação continuada", assumidos como processos complexos que se interpenetram em meio às redes de saberesfazeres tecidas e partilhadas pelos sujeitos das escolas. Podemos inferir, a partir das pistas encontradas, que o cotidiano exige dos pesquisadores em educação outras possibilidades teórico-metodológicas, diferentes daquelas herdadas da modernidade, para superar o aprisionamento do cotidiano em categorias prévias e assegurar a impossibilidade de usarmos o singular para tratar da diversidade que se manifesta na vida.

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O texto apresenta os percursos da investigação realizada numa escola pública de ensino médio do município de Santa Teresa, interior do Espírito Santo. Afirma que, nas ações e inventividades cotidianas dos sujeitos praticantes, são tecidos os processos curriculares que dão movimento à pesquisa, considerando esses praticantes como protagonistas das teoriaspráticas curriculares. Problematiza os modos de ser jovem ao discutir os processos de singularização que acontecem nas relações cotidianas, defendendo uma perspectiva teoricoepistemológica que considera os jovens como sujeitos híbridos que habitam entre-lugares culturais, impossibilitando sua localização em identidades idealizadas ou fixas. Aposta nas relações e criações cotidianas, nos movimentos e tessituras dos currículos que se dão em redes coletivas e compartilhadas de saberesfazessentidos, tecidas entre os jovenspraticantes, seus professores e demais habitantes dos cotidianos escolares para além das uniformidades, padronizações e hierarquias das políticas oficiais de currículos. Assume o processo de hibridação que acontece nessas relações, nas discussões ligadas às teoriaspráticas cotidianas e associa a educação e a produção curricular aos processos culturais mais amplos, reconhecendo os limites da criação de uma definição única e precisa de “currículo”. Nesse sentido, defende o fazer curricular como produção de sentidos, argumentando a favor da criação de currículos hibridizados que se constituem em meio a práticas culturais híbridas, onde os movimentos, usos e negociações devem ser considerados nos processos complexos que os constituem, em meio às criações anônimas que se proliferam nos cotidianos. Assume como opção teoricometodologicopolítica as pesquisas com os cotidianos, utilizando narrativastextuaisimagéticas produzidas nos diferentes contextos da pesquisa pelos praticantes. Evidencia, ainda, que a criação da tese se faz no próprio movimento da escrita, num processo de ficção, discutindo questões ligadas às juventudes, à educação profissionalizante, ao ensino médio, aos modos de pesquisa, às relações cotidianas, às redes de singularidades, aos currículos, aos modelos de escola, às magensnarrativas desses processos, entre outras, sem, no entanto, definir os limites desses campos enunciativos, compondo-se, numa mistura intrigante e complexa de sons, gostos, fazeres, dizeres e calares dos percursos de conhecer, compreendendo a maior “marca cotidiana do cotidiano”.

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Pathogenic fungi that cause systemic mycoses retain several factors which allow their growth in adverse conditions provided by the host, leading to the establishment of the parasitic relationship and contributing to disease development. These factors are known as virulence factors which favor the infection process and the pathogenesis of the mycoses. The present study evaluates the virulence factors of pathogenic fungi such as Blastomyces dermatitidis, Coccidioides immitis, Cryptococcus neoformans, Histoplasma capsulatum and Paracoccidioides brasiliensis in terms of thermotolerance, dimorphism, capsule or cell wall components as well as enzyme production. Virulence factors favor fungal adhesion, colonization, dissemination and the ability to survive in hostile environments and elude the immune response mechanisms of the host. Both the virulence factors presented by different fungi and the defense mechanisms provided by the host require action and interaction of complex processes whose knowledge allows a better understanding of the pathogenesis of systemic mycoses.

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Os espaços públicos das cidades, sobretudo os daquelas para onde converge o turismo mundial, são sujeitos a múltiplos mecanismos de representação que os fragmentam e, em última análise, os reduzem a imagens idealizadas. Os autores dessas imagens, e dos seus sentidos, são muito diversificados, mas os profissionais ligados ao turismo (agências de viagem, revistas turísticas, documentaristas, etc.) e as instâncias públicas interessadas na divulgação turística das cidades (câmaras municipais, governos regionais, etc.) são, sem dúvida, duas das instâncias que mais operam no interior desses processos complexos de representação (e de mercadorização) do espaço das cidades. E se esses processos se associam hoje à relação feliz que milhões de pessoas estabelecem com as cidades no mundo inteiro, é no entanto necessário não esquecer que parte dessas paisagens são cuidadosamente construídas de forma, por um lado, a obliterar a lamentável realidade do urbanismo envolvente e, por outro, a delas excluir todos aqueles que inviabilizam a dinâmica cultural de construção de paisagens. We consider that the public spaces of cities, especially those which converge to the global tourism, are subject to multiple mechanisms of representation that fragment and, ultimately, reduce its idealized images. The authors of these images, and their senses are very diverse, but the professionals linked to tourism (travel agencies, tourist magazines, documentaries, etc.) and the government stakeholders interested in the dissemination of tourist cities (municipalities, regional governments, etc.) are undoubtedly two of the actors that operate within these more complex processes of representation of all urban space. And if these processes are associated today with the happy relationship that millions of people have with cities worldwide, it is however necessary not to forget that part of these landscapes are carefully constructed in a way, on one hand, to obliterate the unfortunate reality of the urban environment and, secondly, to delete all those that prevent the construction of dynamic cultural landscapes.

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The heat- and odour-producing genus Arum (Araceae) has interested scientists for centuries. This long-term interest has allowed a deep knowledge of some complex processes, such as the physiology and dynamics of its characteristic lure-and-trap pollination system, to be built up. However, mainly because of its large distributional range and high degree of morphological variation, species' limits and relationships are still under discussion. Today, the genus comprises 28 species subdivided into two subgenera, two sections and six subsections. In this study, the phylogeny of the genus is inferred on the basis of four plastid regions, and the evolution of several morphological characters is investigated. Our phylogenetic hypothesis is not in agreement with the current infrageneric classification of the genus and challenges the monophyly of several species. This demonstrates the need for a new infrageneric classification based on characters reflecting the evolution of this enigmatic genus. To investigate the biogeography of Arum deeply, further spatiotemporal analyses were performed, addressing the importance of the Mediterranean basin in the diversification of Arum. Our results suggest that its centre of origin was the European-Aegean region, and that major diversification happened during the last 10 Myr.

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Genetic disorders involving the skeletal system arise through disturbances in the complex processes of skeletal development, growth and homeostasis and remain a diagnostic challenge because of their variety. The Nosology and Classification of Genetic Skeletal Disorders provides an overview of recognized diagnostic entities and groups them by clinical and radiographic features and molecular pathogenesis. The aim is to provide the Genetics, Pediatrics and Radiology community with a list of recognized genetic skeletal disorders that can be of help in the diagnosis of individual cases, in the delineation of novel disorders, and in building bridges between clinicians and scientists interested in skeletal biology. In the 2010 revision, 456 conditions were included and placed in 40 groups defined by molecular, biochemical, and/or radiographic criteria. Of these conditions, 316 were associated with mutations in one or more of 226 different genes, ranging from common, recurrent mutations to "private" found in single families or individuals. Thus, the Nosology is a hybrid between a list of clinically defined disorders, waiting for molecular clarification, and an annotated database documenting the phenotypic spectrum produced by mutations in a given gene. The Nosology should be useful for the diagnosis of patients with genetic skeletal diseases, particularly in view of the information flood expected with the novel sequencing technologies; in the delineation of clinical entities and novel disorders, by providing an overview of established nosologic entities; and for scientists looking for the clinical correlates of genes, proteins and pathways involved in skeletal biology. © 2011 Wiley-Liss, Inc.

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There is a general consensus that during chronic Trypanosoma cruzi infection, the host immune system induces complex processes to ensure the control of parasite growth while preserving the potential to mount and maintain a life-long controlled humoral and cellular immune response against the invading pathogen. This review summarises evidence in an attempt to elucidate "what must be understood" to further clarify the role of innate immunity in the development/maintenance of clinical Chagas disease and the impact of etiological treatment on host immunity, highlighting the contributions of the innate immunity and regulatory T (Treg) cells. Recently, increasing focus on innate immunity suggest that chronic T. cruzi infection may cause morbidity when innate effector functions, or the down-regulation of adaptive regulatory mechanisms are lacking. In this context, stable asymptomatic host-parasite interactions seem to be influenced by the effector/regulatory balance with the participation of macrophages, natural killer (NK) and CD8+ T cells in parallel with the establishment of regulatory mechanisms mediated by NKT and Treg cells. Moreover, a balanced innate immune activation state, apart from Treg cells, may play a role in controlling the adverse events triggered by the massive antigen release induced by trypanosomicidal agents during Chagas disease etiological treatment.

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El rápido crecimiento del los sistemas multicore y los diversos enfoques que estos han tomado, permiten que procesos complejos que antes solo eran posibles de ejecutar en supercomputadores, hoy puedan ser ejecutados en soluciones de bajo coste también denominadas "hardware de comodidad". Dichas soluciones pueden ser implementadas usando los procesadores de mayor demanda en el mercado de consumo masivo (Intel y AMD). Al escalar dichas soluciones a requerimientos de cálculo científico se hace indispensable contar con métodos para medir el rendimiento que los mismos ofrecen y la manera como los mismos se comportan ante diferentes cargas de trabajo. Debido a la gran cantidad de tipos de cargas existentes en el mercado, e incluso dentro de la computación científica, se hace necesario establecer medidas "típicas" que puedan servir como soporte en los procesos de evaluación y adquisición de soluciones, teniendo un alto grado de certeza de funcionamiento. En la presente investigación se propone un enfoque práctico para dicha evaluación y se presentan los resultados de las pruebas ejecutadas sobre equipos de arquitecturas multicore AMD e Intel.