José Pedro Tavares

A Conceptual MAS Model for Real-Time Traffic Control

This paper presents the description of the various steps to analyze and design a multi-agent system for the real-time traffic control at isolated intersections. The control strategies for traffic signals are a high-importance topic due to impacts on economy, environment and society, affecting people and freight transport that have been studied by many researches during the last decades. The research target is to develop an approach for controlling traffic signals that rely on flexibility and maximal level of freedom in control where the system is updated frequently to meet current traffic demand taking into account different traffic users. The proposed model was designed on the basis of the Gaia methodology, introducing a new perspective in the approach where each isolated intersection is a multi-agent system on its own right.

Comparison of condylar displacement between three biotypological facial groups by using mounted models and a mandibular position indicator.

Objective Facial-type-associated variations in diagnostic features have several implications in orthodontics. For example, in hyperdivergent craniofacial types, growth imbalances are compensated by displacement of the condyle. When diagnosis and treatment planning involves centric relation (CR), detailed knowledge of the condylar position is desirable. The present study aimed to measure condylar displacement (CD) between CR and maximum intercuspation in three facial types of an asymptomatic orthodontic population. Methods The study was conducted in 108 patients classified into three groups of 36 individuals each (27 women and 9 men; mean age, 20.5 years), based on the following facial patterns: hyperdivergent, hypodivergent, and intermediate. To quantify CD along the horizontal and vertical axes, the condylar position was analyzed using mounted casts on a semi-adjustable articulator and a mandibular position indicator. The Student t-test was used to compare CD between the groups. Results Vertical displacement was found to be significantly different between the hyperdivergent and hypodivergent groups (p < 0.0002) and between the hyperdivergent and intermediate groups (p < 0.0006). The differences in horizontal displacement were not significant between the groups. In each group, vertical CD was more evident than horizontal displacement was. Conclusions All facial types, especially the hyperdivergent type, carried a significantly high risk of CD. Therefore, the possibility of CD should be carefully evaluated and considered in the assessment of all orthodontic cases in order to accurately assess jaw relationships and avoid possible misdiagnosis.

Design of a Multiagent System for Real-Time Traffic Control

This article describes the various steps to analyze and design a multiagent system for real-time traffic control at isolated intersections. The control strategies for traffic signals are important because they impact the economy, environment, and society and also affect freight transport, which many researchers have studied over the years. The research community has focused on the optimization of traffic signal plans. Although these efforts have been relatively successful, the strategies lack flexibility, which limits their effectiveness. In addition to defining the best traffic plan at the design phase, researchers must aim to maintain the system optimized during the operation phase. In this way, the research target is to develop an approach for controlling traffic signals that relies on flexibility and maximum freedom in control, in which the system is updated frequently to meet traffic demand, taking into account different traffic users. This studys main outcome is a conceptual model of a novel perspective of a multiagent system for real-time traffic control at isolated intersections. This model, which was based on the Gaia methodology, introduces a new perspective in which each isolated intersection is itself a multiagent system. The many agents designed for isolated intersections create, manage, and evolve their own traffic signal plans. Therefore, this proposed multiagent control brings the benefit of staged designs and sequences being formed as needed instead of being established a priori.