Petri net based development of globally-asynchronous locally-synchronous distributed embedded systems

Dissertação para obtenção do Grau de Doutor em Engenharia Electrotécnica e de Computadores

An evolutionary approach to the use of Petri net based models: from parallel controllers to HW/SW co-design

"A workshop within the 19th International Conference on Applications and Theory of Petri Nets - ICATPN’1998"

MORM--a Petri net based model for assessing OH&S risks in industrial processes: modeling qualitative aspects.

Because of the increase in workplace automation and the diversification of industrial processes, workplaces have become more and more complex. The classical approaches used to address workplace hazard concerns, such as checklists or sequence models, are, therefore, of limited use in such complex systems. Moreover, because of the multifaceted nature of workplaces, the use of single-oriented methods, such as AEA (man oriented), FMEA (system oriented), or HAZOP (process oriented), is not satisfactory. The use of a dynamic modeling approach in order to allow multiple-oriented analyses may constitute an alternative to overcome this limitation. The qualitative modeling aspects of the MORM (man-machine occupational risk modeling) model are discussed in this article. The model, realized on an object-oriented Petri net tool (CO-OPN), has been developed to simulate and analyze industrial processes in an OH&S perspective. The industrial process is modeled as a set of interconnected subnets (state spaces), which describe its constitutive machines. Process-related factors are introduced, in an explicit way, through machine interconnections and flow properties. While man-machine interactions are modeled as triggering events for the state spaces of the machines, the CREAM cognitive behavior model is used in order to establish the relevant triggering events. In the CO-OPN formalism, the model is expressed as a set of interconnected CO-OPN objects defined over data types expressing the measure attached to the flow of entities transiting through the machines. Constraints on the measures assigned to these entities are used to determine the state changes in each machine. Interconnecting machines implies the composition of such flow and consequently the interconnection of the measure constraints. This is reflected by the construction of constraint enrichment hierarchies, which can be used for simulation and analysis optimization in a clear mathematical framework. The use of Petri nets to perform multiple-oriented analysis opens perspectives in the field of industrial risk management. It may significantly reduce the duration of the assessment process. But, most of all, it opens perspectives in the field of risk comparisons and integrated risk management. Moreover, because of the generic nature of the model and tool used, the same concepts and patterns may be used to model a wide range of systems and application fields.

A petri net based timing model for hardware/software co-design of digital systems

We have recently proposed an extension to Petri nets in order to be able to directly deal with all aspects of embedded digital systems. This extension is meant to be used as an internal model of our co-design environment. After analyzing relevant related work, and presenting a short introduction to our extension as a background material, we describe the details of the timing model we use in our approach, which is mainly based in Merlin's time model. We conclude the paper by discussing an example of its usage. © 2004 IEEE.

"TEACHING FROM A CRITICAL, ANTI-RACIST PERSPECTIVE-BASED PEDAGOGY TO PREPARE WHITE STUDENTS FOR CULTURAL DIVERSITY: RESISTANCE AND CONSEQUENCES"

How are faculty of color retained once they are recruited? More importantly, how do factors such as white student resistance and negative disposition toward faculty of color impact the retention of faculty of color?

An efficient, approximate path-following algorithm for elastic net based nonlinear spike enhancement

Unwanted spike noise in a digital signal is a common problem in digital filtering. However, sometimes the spikes are wanted and other, superimposed, signals are unwanted, and linear, time invariant (LTI) filtering is ineffective because the spikes are wideband - overlapping with independent noise in the frequency domain. So, no LTI filter can separate them, necessitating nonlinear filtering. However, there are applications in which the noise includes drift or smooth signals for which LTI filters are ideal. We describe a nonlinear filter formulated as the solution to an elastic net regularization problem, which attenuates band-limited signals and independent noise, while enhancing superimposed spikes. Making use of known analytic solutions a novel, approximate path-following algorithm is given that provides a good, filtered output with reduced computational effort by comparison to standard convex optimization methods. Accurate performance is shown on real, noisy electrophysiological recordings of neural spikes.

ESys.Net : a new .Net based system-level design environment

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

ESys.Net : a new .Net based system-level design environment

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Changing the Face of Traditional Education

At large, research universities, a common approach for teaching hundreds of undergraduate students at one time is the traditional, large, lecture-based course. Trends indicate that over the next decade there will be an increase in the number of large, campus courses being offered as well as larger enrollments in courses currently offered. As universities investigate alternative means to accommodate more students and their learning needs, Web-based instruction provides an attractive delivery mode for teaching large, on-campus courses. This article explores a theoretical approach regarding how Web-based instruction can be designed and developed to provide quality education for traditional, on-campus, undergraduate students. The academic debate over the merit of Web-based instruction for traditional, on-campus students has not been resolved. This study identifies and discusses instructional design theory for adapting a large, lecture-based course to the Web.

Un contrat pédagogique : l'entente sur mesures volontaires dans l'application de la Loi sur la protection de la jeunesse

"Thèse présentée à la Faculté des études supérieures en vue de l'obtention du grade de Docteur en droit (LL.D.)"

Pédagogie par projet et intégration des TIC : quel impact sur la motivation scolaire ?

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Om lärarskapets moraliska dimension : ett perspektiv och en studie av lärarstuderandes nätbaserade seminariesamtal

In this dissertation, an educational perspective called the moral dimension of teaching is developed. The work includes a theoretically informed discussion from a pragmatist point of view in which the concept of pedagogical rhythm is introduced. The concept captures the need for teachers to regularly shift their intentions and occasionally act in contradictory ways as a consequence of the moral which emerges from interaction in pedagogical situations. Using this perspective, criteria are developed for the characteristics of discussions of the work of teachers, which are desirable in order for students in pre-service teacher education to have opportunities to develop their teachership. Secondly, the educational perspective as it is conceptualised serves as a theoretical framework for a study of discussions taking place in net-based seminars among students in teacher education. The study consists of 14 recorded seminars in which discussions of the work of teachers are analysed in terms of content and direction for reflection. The result of the analysis is a construction of four different focal points for processes of making judgements: existential, performative, critical and professional. Mainly the performative, and to some extent the critical, focal points appear to be supported by the net-based environment, although potential for the professional focal point is found when available tools in net-based settings are used in deliberate ways. Finally, based on these four focal points, possible future predispositions among student teachers are deliberated. Student teachers’ future opportunities to develop a moral and epistemological authority are discussed, as well as teachers’ general opportunities to exercise professional responsibility. The conclusion emphasises that a perspective such as the one developed in the dissertation is important, as it creates an understanding for the need to educate student teachers to exercise a form of responsibility that goes beyond being accountable to society.

Entre a teoria e a prática: o projeto político-pedagógico do curso de medicina da UFMA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Social Support Quality in Internet Based Information and Communication: From "Digital Divide" to "Voice Divide"

National and international studies demonstrate that the number of teenagers using the inter-net increases. But even though they actually do have access from different places to the in-formation and communication pool of the internet, there is evidence that the ways in which teenagers use the net - regarding the scope and frequency in which services are used as well as the preferences for different contents of these services - differ significantly in relation to socio-economic status, education, and gender. The results of the regarding empirical studies may be summarised as such: teenager with low (formal ) education especially use internet services embracing 'entertainment, play and fun' while higher educated teenagers (also) prefer intellectually more demanding and particularly services supplying a greater variety of communicative and informative activities. More generally, pedagogical and sociological studies investigating "digital divide" in a dif-ferentiated and sophisticated way - i.e. not only in terms of differences between those who do have access to the Internet and those who do not - suggest that the internet is no space beyond 'social reality' (e.g. DiMaggio & Hargittai 2001, 2003; Vogelgesang, 2002; Welling, 2003). Different modes of utilisation, that structure the internet as a social space are primarily a specific contextualisation of the latter - and thus, the opportunities and constraints in virtual world of the internet are not less than those in the 'real world' related to unequal distribu-tions of material, social and cultural resources as well as social embeddings of the actors involved. This fact of inequality is also true regarding the outcomes of using the internet. Empirical and theoretical results concerning forms and processes of networking and commu-nity building - i.e. sociability in the internet, as well as the social embeddings of the users which are mediated through the internet - suggest that net based communication and infor-mation processes may entail the resource 'social support'. Thus, with reference to social work and the task of compensating the reproduction of social disadvantages - whether they are medial or not - the ways in which teenagers get access to and utilize net based social sup-port are to be analysed.