Fernando Nunes Ferreira

Lighting design: a goal based approach using optimisation

There is a need for reliable lighting design applications because available tools are limited and inappropriate for interactive or creative use. Architects and lighting designers need those applications to define, predict, test and validate lighting solutions for their problems. We present a new approach to the lighting design problem based on a methodology that includes the geometry of the scene, the properties of materials and the design goals. It is possible to obtain luminaire characteristics or other kind of results that maximise the attainment of the design goals, which may include different types of constraints or objectives (lighting, geometrical or others). The main goal, in our approach, is to improve the lighting design cycle. In this work we discuss the use of optimisation in lighting design, describe the implementation of the methodology, present real-world based examples and analyse in detail some of the complex technical problems associated and speculate on how to overcome them.

Graphical control of autonomous, virtual vehicles

This paper presents some of the developments we made with the goal of allowing a friendly control and simulation of a large number of autonomous agents based in behavior in interactive real-time systems. Our work has been specially oriented to the simulation and control of autonomous vehicles and pedestrians in the preparation of scenarios to driving simulation experiments in the DriS simulator. Because every element is intrinsically autonomous, only a few of them are usually addressed to implement the desired study event. Also, because our model is autonomous and controllable, we can use the same model in the implementation of both environment traffic and controlled vehicles. Our scripting language is based in Grafcet, a well known graphical language used in the specification and programming of industrial controllers. Our technique allows the imposition of both short time orders and long time goals to each autonomous element. Orders can be triggered reactively using sensors that monitor the state of virtual traffic and configurable timers that generate all the necessary fixed and variable time events.

Modelling urban scenes for LBMS

Three-dimensional graphical applications can provide an added value to Location Based Mobile Services (LBMS). This is particularly true for the applications related to urban environments, which can interactively present three-dimensional models to the user, visualized in accordance to his location. Modelling an urban environment is mainly a manual procedure and so it can become a difficult, tedious and time consuming task, due to the many different geometries, textures, details, etc, involved in the urban structures.This paper presents the XL3D modelling system that provides, in an automatic fashion, three-dimensional models of urban areas to be used in a LBMS Project. The XL3D modelling system is based on interoperable access to digital data, in diverse formats, accessing XML documents or invoking Web services in a distributed architecture. The system is driven by L-systems based modelling processes that automatically generate three-dimensional models of urban environments, specified in a declarative mode using documents based on an XML Schema, also called XL3D.

Strategies and Implementation of Ray-Tracing with Increasing Realism

Images produced by the ray-tracing algorithm are considered as having a good quality and a high level of realism. Still the algorithm can not be used in low price systems due to the great demanding of processing time required.

Tratamiento de hernia ventral compleja contaminada en dos etapas

El tratamiento de las hernias ventrales complejas contaminadas o muy contaminadas es un reto aun sin una estrategia tecnico-quirurgica definida en la literatura medica. Presentamos el caso de un hombre con una hernia ventral compleja muy contaminada de la protesis sintetica por Staphylococcus aureus resistente a meticilina, en el que se opto por una cirugia en dos etapas con una semana intercalada de tratamiento antibiotico. En el posoperatorio desarrollo un seroma tratado de forma conservadora, y a los 6 meses de seguimiento no se evidencia recidiva ,“abombamiento” de la pared abdominal ni “rechazo” de la protesis. El resultado favorable obtenido con esta estrategia elegida -tecnica en 2 etapas- induce a conjeturar si el manejo terapeutico seguido en este paciente podria ser efectivo para evitar desmasiado tiempo de convalecencia en hernias incisionales complejas contaminadas.

Abdominal Views: Technique, Anatomy, Abnormal Images, Scanning Tips, and Tricks

Background: Efficient integrated emergency medical systems are lowering mortality rates comparatively to the past in trauma management. Focused assessment with sonography for trauma aids in the detection of the source of bleeding. This exam may expedite definite care and lower costs of treatment if the proper surgical management is applied and most importantly in the hemodynamically unstable patient.

Minimally Invasive Component Separation in the Repair of Large Abdominal Wall Defects

The minimally invasive component separation technique is a feasible and reproducible procedure that restores the abdominal midline in many large defects, helping to promote physiological abdominal reconstruction. It is of special use when dealing with a contaminated setting as it can lead to abdominal midline closure without applying prosthetic material. If complete midline restoration is not possible, component separation helps reduce the abdominal wall defect, decreasing the amount of prosthetic material necessary for a bridge repair, respecting as much as possible the physiology and kinetics of the abdominal wall. The minimally invasive component separation technique has many advantages over classic open techniques, avoiding large skin flaps and consequent problems related to wound healing. More studies are needed to compare different minimally invasive techniques regarding advancement of myofascial flaps and respective costs. In this chapter, we describe and illustrate in detail the video-assisted component separation technique and discuss special settings for its use, such as in the primary closure of the difficult open abdomen. Finally, it is fundamental to keep in mind that the minimally invasive component separation technique is only one helpful part in the puzzle involving large and complex abdominal wall defects. Proper planning and attention to details are important for successful achievement of closure.