José Alves Marques

Extending the operating system to support an object-oriented environment

Comandos is a project within the European Strategic Programme for Research on Information Technology - ESPRIT and it stems from the identified need of providing simpler and more integrated environments for application development in large distributed systems. The fundamental goal of the project is the definition of an integrated platform providing support for distributed and concurrent processing in a LAN environment, extensible and distributed data management and tools for monitoring and administrating the distributed environment. An object oriented approach was used as the ground level for the integration of the multidisciplinary concepts addressed in the project. This paper starts by describing the basic model and architecture of Comandos, which results from a common effort by all the partners in the project. We focus then on the description of a first prototype of the system, which implements a subset of the architecture and is currently running on a set of personal computers and workstations at INESC. The prototype is a testbed for the architecture, providing dynamic linking, access to persistent objects and transparent distribution. Special attention is given to the performance aspects of object invocation in virtual memory.

Sensorization and Intelligent Systems in Energetic Sustainable Environments

Sustainability is an important topic of discussion in our world. However, measuring sustainability and assessing behaviors is not always easy. Indeed, and in order to fulfill this goal, in this work it will be proposed a multi-agent based architecture to measure and assess sustainable indicators taken from a given environment. These evaluations will be based on past and present behaviors of the users and the particularities of the setting, leading to the evaluation of workable indicators such as gas emissions, energetic consumption and the users fitting with respect to the milieu. Special attention is given to user interaction and user attributes to calculate sustainable indicators for each type of structure, i.e., the aim of this scheme is to promote sustainability awareness and sustainable actions through the use of sustainable markers calculated in terms of the information gathered from the environment.

Dynamically improving collective environments through mood induction procedures

In our daily living, the environment surrounding us influences us as much or more than we influence it. Whether it is a domestic, leisure or working environment, its conditions will certainly have short and long-term effects on aspects such as stress, mood or fatigue, which will in turn influence indicators such as productivity, quality of work, quality of life, personal/group performance or even health. In this paper a dynamic environment is proposed that, based on the behavioural analysis of its users, will adapt its conditions to improve particular indicators. This will result in better working environments, with an impact on the quality of the work produced.

Orthogonal Persistence in a Heterogeneous Distributed Object-Oriented Environment

This paper describes the major issues in the design and implementation of orthogonal persistence in IK. A single and uniform programming paradigm is used to manipulate objects in a persistent and distributed environment. Object references can be freely passed during remote invocations or stored persistently. IK supports orthogonal persistence with type inheritance. Objects are stored persistently when reachable from an Eternal Root, regardless of their type. For programmers, objects are created and manipulated uniformly, independently of the time they persist. Persistent objects are dynamically grouped at run-time into clusters to encapsulate fine-grain language level objects into coarser-grain entities. We present a novel approach to integrate object clustering, naming and garbage collection in persistent systems, and present experimental results.

Models of Transit Systems for Optimization of the Grounded Vehicles Fleet

In order to operate a public transportation system, it is necessary to plan the grounded fleet lines among the various origin/destination spread all over the city to better attend population displacement during the day, which uses the bus transportation system. To improve planning operation of the public transportation system, it is proposed a linear programming model to optimize the overall performance of transit systems, by setting the optimum buses fleet for every bus line of each company constrained to an accepted delay between any two bus stop on the bus circuit but with a minimum profit for the companies. As the routes are different for time to time during the day such as rush hour. The proposed model can cope with all the kinds of patterns during the day and the propose is to optimise the whole transportation system. It is discussed also the complexity of the nature of the dynamic of the transportation system. The mathematical modelling can show us correctly a way to qualify and quantify the routes, what helps to understand the dynamic behavior of the population through time, different situations and epochs. Simulations present the viability of implantation for real time system to estimate the transportation system as it changes.