Abstract
Parallelizing rendering algorithms to exploit multiprocessor and multicore machines isn't straightforward. Certain methods require frequent synchronization among threads to obtain benefits similar to the sequential algorithm. One such algorithm is the irradiance cache (IC), an acceleration data structure that caches indirect diffuse irradiance values. In multicore systems, the threads must share the IC to achieve high efficiency. A proposed wait-free mechanism for accessing the shared IC doesn't use the common blocking or busy-waiting methods, thus avoiding most serialization and reducing contention. A comparison with two classic approachesa lock-based mechanism and a local-write techniqueon two systems with up to 24 cores shows that the wait-free approach significantly reduces synchronization overhead, thus improving performance. The Web extra PDF augments the article. The Web extra video is an animation that demonstrates the wait-free IC system running at close to interactive rates on an 8-core machine. © 2006 IEEE.

Abstract

Abstract
This paper describes a segmentation method for automating the region of interest (ROI) delineation in chromatographic images, thus allowing the definition of the image area that contains the fundamental information for further processing while excluding the frame of the chromatographic plate that does not contain relevant data for disease identification. This is the first component of a screening tool for Fabry disease, which will be based on the automatic analysis of the chromatographic patterns extracted from the image ROI. Image segmentation is performed in two phases, where each individual pixel is finally considered as frame or ROI. In the first phase, an unsupervised learning method is used for classifying image pixels into three classes: frame, ROI or unknown. In the second phase, distance features are used for deciding which class the unknown pixels belong to. The segmentation result is post-processed using a sequence of morphological operators in order to obtain the final ROI rectangular area. The proposed methodology was successfully evaluated in a dataset of 41 chromatographic images.

Abstract
In the past, several approaches have been devised to semi- automate the multidimensional design (MDD) of Data Warehouse (DW) projects. Such approaches highly contribute to more expertise- independent and deterministic MDD results. Among them, only the Dimensional Templates Approach (DTA) focuses on solving the critical resource containment problems of DW prototypes. Originally, the DTA allows solely the generation of basic MDDs. In this paper, we depict an extension to address complex MDD issues. These include (i) date/time hierarchies, (ii) many-to-many relationships, (iii) hierarchically structured data and (iv) coverage facts. The proposed enhancements, including a rebuilt generation algorithm, allow more accurate and broadening results than the original DTA. Throughout the paper, references are made to a real case study to which the improved DTA has been applied using two developed prototype tools. © 2011 Springer-Verlag.

Abstract
Large deployment of Plug-in Hybrid Electric Vehicles (PHEVs) will put new challenges regarding the power systems operation. The MicroGrid (MG) concept can be exploited to support the progressive integration of PHEVs into the Low Voltage (LV) networks by developing smart charging strategies to manage the PHEVs batteries charging procedures in order to avoid reinforcements in the grid infrastructures. Assuming that a number of PHEVs owners allow managing the batteries charging when their cars are parked, this paper proposes an approach that aims to find suitable individual active power set-points corresponding to the hourly charging rate of each PHEV battery connected to the LV grid. The Evolutionary Particle Swarm Optimization (EPSO) tool is used to find these active power set points. This requires an additional software module to be housed in the MV/LV secondary substation level, called Optimal Power Set-points Calculator (OPSC). © 2011 IEEE.

Abstract
The purpose of this study is to confirm the structural validity of the Questionario de Estilos Educativos Parentais (QEEP) in a sample of Portuguese adolescents. This instrument is an adaptation of the Parenting Scales to the Portuguese population and intends to evaluate adolescents' perceptions of the rearing style of their parents. It is composed of 19 items related with two dimensions: Acceptance (Responsiveness) and Monitoring (Supervision). The sample has comprised 210 boys and 213 girls aged from 12 to 15 years. A two-dimensional model has emerged from confirmatory factorial analysis - Acceptance, similar to the original subscale, and Knowledge, composed by some items from the Monitoring dimension. Internal consistency coefficients are acceptable for research purposes.