Rafael Luiz Cancian - Academia.edu (original) (raw)
Papers by Rafael Luiz Cancian
Anais Do Computer on the Beach, 2015
Rev Bras Anal Clin, 2008
... Estudos realizados por Garcia-Martinez e colaboradores (1996) demonstraram que a análise de R... more ... Estudos realizados por Garcia-Martinez e colaboradores (1996) demonstraram que a análise de RFLP da região inter-gênica 16S-23S de ... based on intergenic 16s-23s RFLP of Escherichia coli strains obtained from urine samples of ambulatorial pacients Gisele Kleine Neves1 ...
2006 Ieee Conference on Emerging Technologies and Factory Automation, 2006
Nowadays development strategies are not suitable for the design of many embedded systems applicat... more Nowadays development strategies are not suitable for the design of many embedded systems applications, be-cause they do not guide the developer in the use of nowadays software engineering concepts as aspects and generic programming. The present work shows the pros and ...
Anais Do Computer on the Beach, 2010
Embedded systems are usually designed using a repository of reusable components. To be reusable, ... more Embedded systems are usually designed using a repository of reusable components. To be reusable, however, components must be designed for that. A common technique used to identify and design reusable components is the domain engineering. This paper presents the development of a software tool that starts from a domain model and generates a repository of components in a semiautomatic way. The repository includes the source-code and testers structure of components and the meta data for their characterization. As a study case a domain model for embedded operating system was used to generate a repository. Results show that a well done domain model with an adequate detail level allows the code generation and characterization of components and families of components that can really be used for automatically component selection and for designing several applications. Resumo. Sistemas embarcados são comumente desenvolvidos a partir de um conjunto ou repositório de componentes reusáveis. Entretanto, para serem reusáveis, esses componentes precisam ser projetados com esse objetivo. Uma técnica utilizada para identificar e projetar componentes reusáveis é a engenharia de domínio. Este artigo apresenta o desenvolvimento de uma ferramenta que, a partir de um modelo de domínio gerado pelo usuário, realiza a geração semi-automática de um repositório de componentes, incluindo a infra-estrutura dos componentes, testadores e seus metadados para caracterização dos componentes e posterior seleção. Como estudo de caso utilizou-se um modelo de domínio que representa sistemas operacionais embarcados. Os resultados demonstram que uma boa modelagem do domínio com o nível de detalhamento adequado permite a geração de código e a caracterização de componentes e famílias de componentes que, efetivamente, podem ser utilizados por uma ferramenta para seleção automática de componentes e geração de diferentes aplicações embarcadas.
Anais Do Computer on the Beach, 2010
This paper presents the development of components for hardware simulation of embedded systems in ... more This paper presents the development of components for hardware simulation of embedded systems in a generic simulation tool. This simulator can simulate models described by the user and to collect statistics automatically for further analysis. This simulator was used to model embedded systems at high level of abstraction and to verify if it's possible to obtain performance estimates in the very first steps of development, without completellty specify the embedded system and withou using low level and accurate simulators. Validation was performed by statistically comparing the results with hypothesis tests. Results show that hight level simulators using the developed components can be usefull if confidence level is relaxed to something like 73%.
Resumo-The increasing complexity of embedded systems demands the use of adequate design methodolo... more Resumo-The increasing complexity of embedded systems demands the use of adequate design methodologies and tools to support them. The component based design and the design space exploration are central points in the development of embedded systems, and are closely related to the modeling of the component repository. In this paper we present three main advances in the EPOS (Embedded and Parallel Operating System) repository to support design space exploration: the creation of the repository from a domain model, a more complete representation of software, synthetizable and physical hardware components, architectures and programmable logical devices, and keeping a history of designed systems and estimated component costs.
Here we describe a project that is being conduced at UNIVALI-Computer Science Center. Its main ob... more Here we describe a project that is being conduced at UNIVALI-Computer Science Center. Its main objective is to develop a software to simulate the DNA replication and translation processes in a user defined environment (temperature, molecule concentration, cell state, etc). Based in the cellular automata technique, the simulator will present a bi-dimensional graphical view of the molecules (DNA, RNA, nucleotides and specific enzymes) interactions. At present the software is being considered a great tool for molecular biology education, however if improved to a tri-dimensional environment it may also be tested for research applications.
2009 International Conference on Computational Science and Engineering, 2009
Abstract A major subject in real-time embedded systems is the management,of the tasks that compos... more Abstract A major subject in real-time embedded systems is the management,of the tasks that compose the system re- specting its real-time constraints. This is usually ac- complished by the adequate selection of a scheduling policy. This work proposes a design and implemen- tation of real-time schedulers for embedded,systems within the context of Application Oriented System Design (AOSD), enabling the development
Embedded systems design gets more complex as result of low cost provided by the technology advanc... more Embedded systems design gets more complex as result of low cost provided by the technology advance, that allows the development of more com- plex embedded applications, like multimedia processing in cell phones. Most common development strategies are not suitable for the design of real-time and extremmely adapted applications. Application-oriented system design (AOSD) strategy has shown efficient to embedded systems software
Q2SWinet'08: Proceedings of the 4th ACM International Symposium on QoS and Security for Wireless and Mobile Networks, 2008
IEEE 802.11 standard for wireless networks recently has been enhanced with IEEE 802.11e amendment... more IEEE 802.11 standard for wireless networks recently has been enhanced with IEEE 802.11e amendment to this protocol which introduces Quality of Service support. It provides differentiation mechanisms at the Medium Access Control layer, using two additional access functions: the Enhanced Distributed Channel Access (EDCA) function and the HCF Controlled Channel Access (HCCA) function. The EDCA function is based on a distributed control and enables prioritized channel access while the latter requires centralized scheduling and allows the applications to negotiate parameterized service guarantees. Only HCCA mechanism is suitable for serving traffic streams with real-time requirements such as multimedia applications and Voice Over IP. The IEEE 802.11e standard does not specify a mandatory HCCA scheduling algorithm, while it offers a reference scheduler. In this paper we analyze four HCCA schedulers which are alternative to the reference one and which offer real-time guarantees. A performance evaluation through simulation is conducted to show the main differences between the considered schedulers, including the reference one.
2007 IEEE Conference on Emerging Technologies & Factory Automation (EFTA 2007), 2007
... Laboratory for Hardware and Software Integration (LISHA) Computer Science Department (INE) Fe... more ... Laboratory for Hardware and Software Integration (LISHA) Computer Science Department (INE) Federal University of Santa Catarina (UFSC) guto@lisha.ufsc.br ... Despite all re-search and optimism, [5] from Xilix Research Labs, says that there's no actual compiler in position to ...
2006 IEEE Conference on Emerging Technologies and Factory Automation, 2006
Nowadays development strategies are not suitable for the design of many embedded systems applicat... more Nowadays development strategies are not suitable for the design of many embedded systems applications, because they do not guide the developer in the use of nowadays software engineering concepts as aspects and generic programming. The present work shows the pros and cons of Application-Oriented System Design (AOSD) strategy used in the design of a case study embedded system, aiming at AOSD methodology improvement. The disadvantages found in this case study may contribute to improve hardware generation according to AOSD.
Here we describe a project t hat i s being conduced at UNIVALI - Computer Science Center. Its mai... more Here we describe a project t hat i s being conduced at UNIVALI - Computer Science Center. Its main objective is to develop a software to simulate the DNA replication and translation processes in a user defined environment (temperature, molecule concentration, cell state, etc). Based in the ce llular automata technique, the simulator will present a bi-dimensional graphical view of the molecules (DNA, RNA, nucleotides and specific enzymes) interactions. At present t he software is being considered a great t ool for molecular biology education, however if improved to a tri-dimensional environment it may also b e tested for research applications. A system simulation is a computational model designed to represent real systems. Its application allows the development of experiments in simulated environments and to analyses the possible behavior of the real system that they represents. The system simulation is good strategy when conducing experiments with real systems are dangerous, expensi...
The Journal of Object Technology, 2007
Embedded systems are comprised of hardware and software and usually run dedicated applications in... more Embedded systems are comprised of hardware and software and usually run dedicated applications in environments with highly restricted resources, such as memory constrained devices, microcontrollers with low processing power, and wireless sensors running on batteries. These systems must exactly match applications' requirements, with minimum support. The growth in application complexity and even more strong constraints demand new approaches, methodologies, and tools to assist embedded systems development. Usually, in this domain, reuse of components, architectural transparency, low overhead, and reconfigurability are essential features. The Application-Oriented System Design (AOSD) method was created to deal with these issues, and aims at guiding the development of embedded systems that exactly match application requirements. To deliver each application a tailored run-time support system calls for a good combination of object oriented techniques, the separation of functional and non-functional aspects, some implementation techniques, and a sophisticated tool that helps the developer in managing component configurations and automating the generation of embedded systems. This paper describes a configuration and system generation tool that is being successfully used with EPOS (Embedded and Parallel Operating System), an OS developed using AOSD. This tool receives the application source-code (using EPOS API) as input and, after a few mouse clicks, builds the entire computational support, comprised by software and, if hardware is reconfigurable, the FPGA configuration file. This paper also shows that the design of these tools allows them to be used for configuring and building several other systems, not only EPOS. The development of this tool enabled the configuration and generation of several embedded systems instances for several different architectures in an automatic way. To illustrate this process and the tool's usage, this paper describes a case study of the generation of an embedded system that supports a simple audio decoder application.
Forestry, 2000
The objective of this work was to evaluate advantages and disadvantages of selected tympanoplasti... more The objective of this work was to evaluate advantages and disadvantages of selected tympanoplastic stages under the endoscopic control during the surgical treatment of 93 patients presenting with chronic otitis media. The endoscopic techniques has indisputable advantages over traditional surgical microscopy when applied to elucidate the character and extent of the pathological process in the middle ear. This method allows to reveal granulation and cholesteatoma in difficult of access pockets and folds of the middle ear without enlargement of the extent of surgical intervention, to evaluate the "continuity" of the chain of auditory ossicles, etc. At the same time the use of an endoscope during performance of the majority of tympanoplastic procedures creates some difficulties related to the necessity of regular cleaning of the instrument and the impossibility of application of the bimanual technique.
lisha.ufsc.br
1. Resumo Sistemas embarcados sao compostos de hardware e software e normalmente executam aplicaç... more 1. Resumo Sistemas embarcados sao compostos de hardware e software e normalmente executam aplicaçoes dedicadas em ambientes altamente restritivos. No projeto de sistemas embarcados temos caracterısticas altamente desejáves, como o reuso de componentes, ...
lisha.ufsc.br
Embedded systems frequently require an integrated hardware/software design within real time const... more Embedded systems frequently require an integrated hardware/software design within real time constrains. In order to achieve such contrains, an adequate selection of a scheduling policy must be done. This work proposes the design and implementation of real time schedulers for embedded systems, within the context of Application Oriented System Design (AOSD). The use of AOSD enabled the development of schedulers where the policy is detached from the scheduling mechanism, fostering a better reusability of the scheduling components. The results shows that such design could be implemented to scale from 8 bits microcontrollers, 32 bits architectures and to specific hardware implemented design. Resumo. Devido a suas características, sistemas embarcados freqüentemente demandam um projeto integrado de software e hardware com restrições de tempo real. Para que tais restrições sejam respeitadas, uma política de escalonamento de tarefas adequada deve ser selecionada. Este trabalho apresenta a modelagem e implementação de escalonadores de tempo real para sistemas embarcados, no contexto do projeto de sistemas orientadosà aplicação. Esta abordagem permitiu a separação da política de escalonamento e seu mecanismo, promovendo uma maior reusabilidade dos artefatos envolvidos. Os resultados apresentados demonstram que esta implementação permite o seu uso em microcontroladores de 8 bits, arquiteturas de 32 bits, e até mesmo para implementações dedicadas de hardware.
O uso de telescópios de pequeno porte na observação astronômica amadora é muitas vezes restringid... more O uso de telescópios de pequeno porte na observação astronômica amadora é muitas vezes restringido pela dificuldade que astrônomos amadores enfrentam para localizar um astro desejado e acompanhá-lo no céu. Este artigo apresenta o desenvolvimento de um sistema embarcado a ser utilizado na automação de telescópios de pequeno porte visando facilitar a operação desses equipamentos por amadores. O sistema é baseado em um microcontrolador e possui uma interface para o usuário indicar o astro desejado e configurar a observação a ser realizada. 1. Introdução Considerada a mais antiga de todas as ciências, a astronomia já atraia os seres humanos mais primitivos que observavam o céu e tentavam compreender os fenômenos que ocorriam à sua volta, como as variações de luminosidade, de temperatura e de clima, o deslocamento do Sol, os eclipses, as fases da Lua, as passagens de cometas, etc. Com o passar do tempo, esse interesse deu origem a uma ciência natural chamada Astronomia, a qual visa à observação dos astros e a criação de teorias sobre seus movimentos, sua constituição, origem e evolução. A observação dos astros, também chamada de observação astronômica, pode ser feita a olho nu, mas a visão humana é limitada e restringe muito a capacidade dessa observação. Então, faz-se necessário o uso de equipamentos, como, por exemplo, os telescópios ópticos, que permitem "aproximar" corpos celestes observados a longa distância. Na última década houve um avanço da astronomia observacional por meio do desenvolvimento de telescópios de grande porte, como, por exemplo, os telescópios de oito metros de diâmetro [Gemini Observatory, 2006], além de telescópios virtuais e remotos acessíveis via Internet [CARA, 2002][Observatórios Virtuais, 2005] [Werneck, Nader e Campos, 2004]. Nessa direção, verificou-se também um aumento do interesse pela observação astronômica amadora, viabilizada por telescópios de pequeno porte e de menor custo, como o telescópio ilustrado na Figura 1, cuja estrutura de sustentação utiliza uma montagem equatorial alemã (o tipo de montagem alvo deste trabalho).
Abstract—The use of a careful domain,engineering,is essential to achieve,the level of portability... more Abstract—The use of a careful domain,engineering,is essential to achieve,the level of portability,and,efficiency demanded by embedded,systems. The Application Driven Embedded,Sys- tem,Design (ADESD) methodology,guides,the development,of application-oriented,embedded,systems,from,domain,analysis to implementation, and uses several software engineering and implementation,techniques,to achieve,this goal. This paper presents some,implementation,techniques used to support,the de- velopment,of component,based embedded,systems using ADESD methodology. Index Terms—Component Based Design, Application Driven Embedded System Design, Embedded Systems,
Anais Do Computer on the Beach, 2015
Rev Bras Anal Clin, 2008
... Estudos realizados por Garcia-Martinez e colaboradores (1996) demonstraram que a análise de R... more ... Estudos realizados por Garcia-Martinez e colaboradores (1996) demonstraram que a análise de RFLP da região inter-gênica 16S-23S de ... based on intergenic 16s-23s RFLP of Escherichia coli strains obtained from urine samples of ambulatorial pacients Gisele Kleine Neves1 ...
2006 Ieee Conference on Emerging Technologies and Factory Automation, 2006
Nowadays development strategies are not suitable for the design of many embedded systems applicat... more Nowadays development strategies are not suitable for the design of many embedded systems applications, be-cause they do not guide the developer in the use of nowadays software engineering concepts as aspects and generic programming. The present work shows the pros and ...
Anais Do Computer on the Beach, 2010
Embedded systems are usually designed using a repository of reusable components. To be reusable, ... more Embedded systems are usually designed using a repository of reusable components. To be reusable, however, components must be designed for that. A common technique used to identify and design reusable components is the domain engineering. This paper presents the development of a software tool that starts from a domain model and generates a repository of components in a semiautomatic way. The repository includes the source-code and testers structure of components and the meta data for their characterization. As a study case a domain model for embedded operating system was used to generate a repository. Results show that a well done domain model with an adequate detail level allows the code generation and characterization of components and families of components that can really be used for automatically component selection and for designing several applications. Resumo. Sistemas embarcados são comumente desenvolvidos a partir de um conjunto ou repositório de componentes reusáveis. Entretanto, para serem reusáveis, esses componentes precisam ser projetados com esse objetivo. Uma técnica utilizada para identificar e projetar componentes reusáveis é a engenharia de domínio. Este artigo apresenta o desenvolvimento de uma ferramenta que, a partir de um modelo de domínio gerado pelo usuário, realiza a geração semi-automática de um repositório de componentes, incluindo a infra-estrutura dos componentes, testadores e seus metadados para caracterização dos componentes e posterior seleção. Como estudo de caso utilizou-se um modelo de domínio que representa sistemas operacionais embarcados. Os resultados demonstram que uma boa modelagem do domínio com o nível de detalhamento adequado permite a geração de código e a caracterização de componentes e famílias de componentes que, efetivamente, podem ser utilizados por uma ferramenta para seleção automática de componentes e geração de diferentes aplicações embarcadas.
Anais Do Computer on the Beach, 2010
This paper presents the development of components for hardware simulation of embedded systems in ... more This paper presents the development of components for hardware simulation of embedded systems in a generic simulation tool. This simulator can simulate models described by the user and to collect statistics automatically for further analysis. This simulator was used to model embedded systems at high level of abstraction and to verify if it's possible to obtain performance estimates in the very first steps of development, without completellty specify the embedded system and withou using low level and accurate simulators. Validation was performed by statistically comparing the results with hypothesis tests. Results show that hight level simulators using the developed components can be usefull if confidence level is relaxed to something like 73%.
Resumo-The increasing complexity of embedded systems demands the use of adequate design methodolo... more Resumo-The increasing complexity of embedded systems demands the use of adequate design methodologies and tools to support them. The component based design and the design space exploration are central points in the development of embedded systems, and are closely related to the modeling of the component repository. In this paper we present three main advances in the EPOS (Embedded and Parallel Operating System) repository to support design space exploration: the creation of the repository from a domain model, a more complete representation of software, synthetizable and physical hardware components, architectures and programmable logical devices, and keeping a history of designed systems and estimated component costs.
Here we describe a project that is being conduced at UNIVALI-Computer Science Center. Its main ob... more Here we describe a project that is being conduced at UNIVALI-Computer Science Center. Its main objective is to develop a software to simulate the DNA replication and translation processes in a user defined environment (temperature, molecule concentration, cell state, etc). Based in the cellular automata technique, the simulator will present a bi-dimensional graphical view of the molecules (DNA, RNA, nucleotides and specific enzymes) interactions. At present the software is being considered a great tool for molecular biology education, however if improved to a tri-dimensional environment it may also be tested for research applications.
2009 International Conference on Computational Science and Engineering, 2009
Abstract A major subject in real-time embedded systems is the management,of the tasks that compos... more Abstract A major subject in real-time embedded systems is the management,of the tasks that compose the system re- specting its real-time constraints. This is usually ac- complished by the adequate selection of a scheduling policy. This work proposes a design and implemen- tation of real-time schedulers for embedded,systems within the context of Application Oriented System Design (AOSD), enabling the development
Embedded systems design gets more complex as result of low cost provided by the technology advanc... more Embedded systems design gets more complex as result of low cost provided by the technology advance, that allows the development of more com- plex embedded applications, like multimedia processing in cell phones. Most common development strategies are not suitable for the design of real-time and extremmely adapted applications. Application-oriented system design (AOSD) strategy has shown efficient to embedded systems software
Q2SWinet'08: Proceedings of the 4th ACM International Symposium on QoS and Security for Wireless and Mobile Networks, 2008
IEEE 802.11 standard for wireless networks recently has been enhanced with IEEE 802.11e amendment... more IEEE 802.11 standard for wireless networks recently has been enhanced with IEEE 802.11e amendment to this protocol which introduces Quality of Service support. It provides differentiation mechanisms at the Medium Access Control layer, using two additional access functions: the Enhanced Distributed Channel Access (EDCA) function and the HCF Controlled Channel Access (HCCA) function. The EDCA function is based on a distributed control and enables prioritized channel access while the latter requires centralized scheduling and allows the applications to negotiate parameterized service guarantees. Only HCCA mechanism is suitable for serving traffic streams with real-time requirements such as multimedia applications and Voice Over IP. The IEEE 802.11e standard does not specify a mandatory HCCA scheduling algorithm, while it offers a reference scheduler. In this paper we analyze four HCCA schedulers which are alternative to the reference one and which offer real-time guarantees. A performance evaluation through simulation is conducted to show the main differences between the considered schedulers, including the reference one.
2007 IEEE Conference on Emerging Technologies & Factory Automation (EFTA 2007), 2007
... Laboratory for Hardware and Software Integration (LISHA) Computer Science Department (INE) Fe... more ... Laboratory for Hardware and Software Integration (LISHA) Computer Science Department (INE) Federal University of Santa Catarina (UFSC) guto@lisha.ufsc.br ... Despite all re-search and optimism, [5] from Xilix Research Labs, says that there's no actual compiler in position to ...
2006 IEEE Conference on Emerging Technologies and Factory Automation, 2006
Nowadays development strategies are not suitable for the design of many embedded systems applicat... more Nowadays development strategies are not suitable for the design of many embedded systems applications, because they do not guide the developer in the use of nowadays software engineering concepts as aspects and generic programming. The present work shows the pros and cons of Application-Oriented System Design (AOSD) strategy used in the design of a case study embedded system, aiming at AOSD methodology improvement. The disadvantages found in this case study may contribute to improve hardware generation according to AOSD.
Here we describe a project t hat i s being conduced at UNIVALI - Computer Science Center. Its mai... more Here we describe a project t hat i s being conduced at UNIVALI - Computer Science Center. Its main objective is to develop a software to simulate the DNA replication and translation processes in a user defined environment (temperature, molecule concentration, cell state, etc). Based in the ce llular automata technique, the simulator will present a bi-dimensional graphical view of the molecules (DNA, RNA, nucleotides and specific enzymes) interactions. At present t he software is being considered a great t ool for molecular biology education, however if improved to a tri-dimensional environment it may also b e tested for research applications. A system simulation is a computational model designed to represent real systems. Its application allows the development of experiments in simulated environments and to analyses the possible behavior of the real system that they represents. The system simulation is good strategy when conducing experiments with real systems are dangerous, expensi...
The Journal of Object Technology, 2007
Embedded systems are comprised of hardware and software and usually run dedicated applications in... more Embedded systems are comprised of hardware and software and usually run dedicated applications in environments with highly restricted resources, such as memory constrained devices, microcontrollers with low processing power, and wireless sensors running on batteries. These systems must exactly match applications' requirements, with minimum support. The growth in application complexity and even more strong constraints demand new approaches, methodologies, and tools to assist embedded systems development. Usually, in this domain, reuse of components, architectural transparency, low overhead, and reconfigurability are essential features. The Application-Oriented System Design (AOSD) method was created to deal with these issues, and aims at guiding the development of embedded systems that exactly match application requirements. To deliver each application a tailored run-time support system calls for a good combination of object oriented techniques, the separation of functional and non-functional aspects, some implementation techniques, and a sophisticated tool that helps the developer in managing component configurations and automating the generation of embedded systems. This paper describes a configuration and system generation tool that is being successfully used with EPOS (Embedded and Parallel Operating System), an OS developed using AOSD. This tool receives the application source-code (using EPOS API) as input and, after a few mouse clicks, builds the entire computational support, comprised by software and, if hardware is reconfigurable, the FPGA configuration file. This paper also shows that the design of these tools allows them to be used for configuring and building several other systems, not only EPOS. The development of this tool enabled the configuration and generation of several embedded systems instances for several different architectures in an automatic way. To illustrate this process and the tool's usage, this paper describes a case study of the generation of an embedded system that supports a simple audio decoder application.
Forestry, 2000
The objective of this work was to evaluate advantages and disadvantages of selected tympanoplasti... more The objective of this work was to evaluate advantages and disadvantages of selected tympanoplastic stages under the endoscopic control during the surgical treatment of 93 patients presenting with chronic otitis media. The endoscopic techniques has indisputable advantages over traditional surgical microscopy when applied to elucidate the character and extent of the pathological process in the middle ear. This method allows to reveal granulation and cholesteatoma in difficult of access pockets and folds of the middle ear without enlargement of the extent of surgical intervention, to evaluate the "continuity" of the chain of auditory ossicles, etc. At the same time the use of an endoscope during performance of the majority of tympanoplastic procedures creates some difficulties related to the necessity of regular cleaning of the instrument and the impossibility of application of the bimanual technique.
lisha.ufsc.br
1. Resumo Sistemas embarcados sao compostos de hardware e software e normalmente executam aplicaç... more 1. Resumo Sistemas embarcados sao compostos de hardware e software e normalmente executam aplicaçoes dedicadas em ambientes altamente restritivos. No projeto de sistemas embarcados temos caracterısticas altamente desejáves, como o reuso de componentes, ...
lisha.ufsc.br
Embedded systems frequently require an integrated hardware/software design within real time const... more Embedded systems frequently require an integrated hardware/software design within real time constrains. In order to achieve such contrains, an adequate selection of a scheduling policy must be done. This work proposes the design and implementation of real time schedulers for embedded systems, within the context of Application Oriented System Design (AOSD). The use of AOSD enabled the development of schedulers where the policy is detached from the scheduling mechanism, fostering a better reusability of the scheduling components. The results shows that such design could be implemented to scale from 8 bits microcontrollers, 32 bits architectures and to specific hardware implemented design. Resumo. Devido a suas características, sistemas embarcados freqüentemente demandam um projeto integrado de software e hardware com restrições de tempo real. Para que tais restrições sejam respeitadas, uma política de escalonamento de tarefas adequada deve ser selecionada. Este trabalho apresenta a modelagem e implementação de escalonadores de tempo real para sistemas embarcados, no contexto do projeto de sistemas orientadosà aplicação. Esta abordagem permitiu a separação da política de escalonamento e seu mecanismo, promovendo uma maior reusabilidade dos artefatos envolvidos. Os resultados apresentados demonstram que esta implementação permite o seu uso em microcontroladores de 8 bits, arquiteturas de 32 bits, e até mesmo para implementações dedicadas de hardware.
O uso de telescópios de pequeno porte na observação astronômica amadora é muitas vezes restringid... more O uso de telescópios de pequeno porte na observação astronômica amadora é muitas vezes restringido pela dificuldade que astrônomos amadores enfrentam para localizar um astro desejado e acompanhá-lo no céu. Este artigo apresenta o desenvolvimento de um sistema embarcado a ser utilizado na automação de telescópios de pequeno porte visando facilitar a operação desses equipamentos por amadores. O sistema é baseado em um microcontrolador e possui uma interface para o usuário indicar o astro desejado e configurar a observação a ser realizada. 1. Introdução Considerada a mais antiga de todas as ciências, a astronomia já atraia os seres humanos mais primitivos que observavam o céu e tentavam compreender os fenômenos que ocorriam à sua volta, como as variações de luminosidade, de temperatura e de clima, o deslocamento do Sol, os eclipses, as fases da Lua, as passagens de cometas, etc. Com o passar do tempo, esse interesse deu origem a uma ciência natural chamada Astronomia, a qual visa à observação dos astros e a criação de teorias sobre seus movimentos, sua constituição, origem e evolução. A observação dos astros, também chamada de observação astronômica, pode ser feita a olho nu, mas a visão humana é limitada e restringe muito a capacidade dessa observação. Então, faz-se necessário o uso de equipamentos, como, por exemplo, os telescópios ópticos, que permitem "aproximar" corpos celestes observados a longa distância. Na última década houve um avanço da astronomia observacional por meio do desenvolvimento de telescópios de grande porte, como, por exemplo, os telescópios de oito metros de diâmetro [Gemini Observatory, 2006], além de telescópios virtuais e remotos acessíveis via Internet [CARA, 2002][Observatórios Virtuais, 2005] [Werneck, Nader e Campos, 2004]. Nessa direção, verificou-se também um aumento do interesse pela observação astronômica amadora, viabilizada por telescópios de pequeno porte e de menor custo, como o telescópio ilustrado na Figura 1, cuja estrutura de sustentação utiliza uma montagem equatorial alemã (o tipo de montagem alvo deste trabalho).
Abstract—The use of a careful domain,engineering,is essential to achieve,the level of portability... more Abstract—The use of a careful domain,engineering,is essential to achieve,the level of portability,and,efficiency demanded by embedded,systems. The Application Driven Embedded,Sys- tem,Design (ADESD) methodology,guides,the development,of application-oriented,embedded,systems,from,domain,analysis to implementation, and uses several software engineering and implementation,techniques,to achieve,this goal. This paper presents some,implementation,techniques used to support,the de- velopment,of component,based embedded,systems using ADESD methodology. Index Terms—Component Based Design, Application Driven Embedded System Design, Embedded Systems,