Computational design optimization for S-Ducts

In this work, we investigate the computational design of a typical S-Duct that is found in the literature. We model the design problem as a shape optimization study. The design parameters describe the 3D geometrical changes to the shape of the S-Duct and we assess the improvements to the aerodynamic behavior by considering two objective functions: the pressure losses and the swirl. The geometry management is controlled with the Free-Form Deformation (FFD) technique, the analysis of the flow is performed using steady-state computational fluid dynamics (CFD), and the exploration of the design space is achieved using the heuristic optimization algorithm Tabu Search (MOTS). The results reveal potential improvements by 14% with respect to the pressure losses and by 71% with respect to the swirl of the flow. These findings exceed by a large margin the optimality level that was achieved by other approaches in the literature. Further investigation of a range of optimum geometries is performed and reported with a detailed discussion

Interacting with Visualizations

In human-media interactions, visualizations occur in a large variety of forms. However, they remain but a single form of possible feedback towards a user. In this chapter it is argued that human-centered visualization is a fundamental part of human-media interaction and vice versa. To that end, the focus in this chapter lies first on the more general topic of interaction research, thus providing a solid literary ground for the rest of this chapter (Section 3.1). In Section 3.2 the focus shifts towards the question how a display technology influences the way(s) in which interaction with visualization takes place. This path is then broadened in Section 3.3 by focusing on approaches towards interacting multimodally with visualizations. To that end a chronological overview of developments in that field is given, thus providing an insight of trends and required steps in realizing multimodal interactions. Also, future work in this field is deducted from literature and those development trends. Fourthly, Section 3.4 describes the issues at hand for effectively applying visualizations in group-based collaborative and distributed environments. The aim in this chapter is to provide an overview of developments and the current state-of-the-art of approaches in which visualization supports the human-machine interaction process and vice versa. For that, this chapter is finalized with a short summary of issues to deal with while designing interaction for visualization. In addition current and future challenges in interacting with visualizations will be discussed

Surveillance of hospital-acquired infections in Liguria, Italy: results from a regional prevalence study in adult and paediatric acute-care hospitals.

A multi-hospital prevalence study of hospital-acquired infections (HAIs) was carried out between 19 March and 6 April 2007 in Liguria, Italy, being the first to be performed in this region. Of the 29 existing public acute hospitals, 25 took part in the investigation (86.2%). In total, 3176 patients were enrolled in the study, representing a regional average bed-occupancy rate of nearly 70%. Three-hundred and ten HAIs were diagnosed from 283 patients, with an overall prevalence of infections and cases of 9.8% and 8.9%, respectively. Prevalence varied considerably between hospitals, ranging from 0 to 24.4% [95% confidence interval (CI): 15.53-33.27]. Urinary tract infections (UTIs) (30.0%) and respiratory tract infections (RTIs) (26.1%) presented the highest relative frequency, followed by bloodstream infections (BSIs) (14.8%), surgical site infections (11.6%) and gastrointestinal infections (6.5%). Intensive care units (ICUs) and haemato-oncological units showed the highest specific prevalence of HAI, respectively 42.5% (95% CI: 34.48-50.52) and 13.3% (6.28-20.32), with RTI and BSI as the predominant infections. Spinal units (33.3%; 13.14-53.46) and functional-rehabilitation units (18.9%; 17.75-24.06) demonstrated a high rate of urinary tract infections. Uni- and multivariate analyses were performed to assess the main risk factors and conditions associated with HAI, both overall and by site. Our study provides an overall picture of the epidemiology of HAI in Liguria, which may be usefully employed as a starting point to plan and organise future surveillance and control programmes