Abstract
Purpose: Precise needle puncture of the renal collecting system is an essential but challenging step for successful percutaneous nephrolithotomy. We evaluated the efficiency of a new real-time electromagnetic tracking system for in vivo kidney puncture. Materials and Methods: Six anesthetized female pigs underwent ureterorenoscopy to place a catheter with an electromagnetic tracking sensor into the desired puncture site and ascertain puncture success. A tracked needle with a similar electromagnetic tracking sensor was subsequently navigated into the sensor in the catheter. Four punctures were performed by each of 2 surgeons in each pig, including 1 each in the kidney, middle ureter, and right and left sides. Outcome measurements were the number of attempts and the time needed to evaluate the virtual trajectory and perform percutaneous puncture. Results: A total of 24 punctures were easily performed without complication. Surgeons required more time to evaluate the trajectory during ureteral than kidney puncture (median 15 seconds, range 14 to 18 vs 13, range 11 to 16, p 0.1). Median renal and ureteral puncture time was 19 (range 14 to 45) and 51 seconds (range 45 to 67), respectively (p 0.003). Two attempts were needed to achieve a successful ureteral puncture. The technique requires the presence of a renal stone for testing. Conclusions: The proposed electromagnetic tracking solution for renal collecting system puncture proved to be highly accurate, simple and quick. This method might represent a paradigm shift in percutaneous kidney access techniques.

Abstract
The exploration of large networks carries inherent challenges in the visualization of a great amount of data. We built an interactive visualization system for the purpose of exploring a large multidimensional network of news clips over time. These are clips gathered by users from web news sources and references to people or places are extracted from. In this paper, we present the system's capabilities and user interface and discuss its advantages in terms of the browsing and extraction of knowledge from the data. These capabilities include a textual search and associated event detection, and temporal navigation allowing the user to seek a certain date and timespan.

Abstract
The administration of systems and networks is a technical specialized complex task. If large organizations can have in their Information Technology (IT) departments systems and network security specialists, Small and Medium Enterprises (SMEs) typically can't; they have only some computers science broadband IT collaborators that respond by the maintenance of the IT resources, and, in some cases, accumulate with some software development. We make of this view the start point of our research, allying the growing need of securing the IT resources and the information sources which are becoming more and more valuable for every single organization. For SMEs the solution for implement security is, many times, an outsourcing task. The problem is that implementing security is an exercise that overflows the common IT domain, but it starts by fully understanding the organization culture, policies and procedures. This knowledge is something that collaborators learn day by day and not something that we can put on paper easily and tell some outsourced specialists to secure. Even if that could be done, the daily maintenance of the security would be a very hard task. This paper makes considerations about security on SMEs reality and presents a framework that permit a high level approach for implement security, more focused on the organization vision of what we want to do than on a technical vision of how to implement it. The framework hard core is one abstraction layer focused on the organizations perspective and a translator layer of them into technical rules capable of been applied on the IT resources, like servers, computers and network equipments.

Abstract
Healthcare organisations, especially in public sector, have been adopting Lean management practices with increasing outcomes’ evidences in several parts of the world, since the beginning of this century. However, Lean deployment in Healthcare services has been addressed in the literature in a surgical way by an array of case reports addressing the “hard” side of Lean deployment, sometimes with no result’s consistency or even follow-up analysis. This thesis seek to add to the operational side of Lean deployment in Healthcare, a complementary understanding of Lean deployment approaches, addressing both “hard” and “soft” sides, identifying the real constraints of Lean in Healthcare sector and the sustainability factors. Supported by two main literature reviews and a multi-case approach, a deep research on the eligible Portuguese cases was conducted answering the questions: (i) What are the different outcomes from Lean deployment in Healthcare?; (ii) What are the barriers to Lean implementation in Healthcare?; (iii) What enables Lean implementation in Healthcare?; (iv) What are the risks of Lean in Healthcare?; (v) How to measure Lean achievements in Healthcare services?; and (vi) How to develop a sustainable Lean culture? This contribution to the academic debate on Lean deployment in Healthcare creates clarity on what can be called Lean practices in Healthcare settings under the light of the concept’s founders; what pattern of a Lean deployment journey was followed by Healthcare organisations; and how different cultural (organisational and national) contexts can influence the pace in pursuing that pattern.;As organizações de saúde, nomeadamente públicas, têm vindo a adoptar práticas de gestão Lean com crescente evidência de resultados em várias partes do mundo, desde o início deste século. Contudo, a aplicação do Lean em serviços de saúde tem tido um tratamento cirúrgico na literatura, recaindo apenas nos aspectos “hard” e sem grande consistência ou seguimento de resultados . Esta tese pretende acrescentar aos aspectos “hard” do Lean, um entendimento complementar juntando os aspectos “hard” e “soft”, identificando as restrições e factores de sustentabilidade da aplicação do Lean no sector da saúde. Tendo por base duas revisões bibliográficas primordiais e uma abordagem empírica multi-caso a partir de casos portugueses elegíveis, esta tese fornece respostas às questões: (i) Quais os diferentes resultados da aplicação do Lean na Saúde?; (ii) Quais as barreiras à aplicação do Lean na Saúde?; (iii) Quais os facilitadores da implementação do Lean na Saúde?; (iv) Quais os riscos do Lean na Saúde?; (v) Como medir a implementação do Lean na Saúde; e (vi) como desenvolver uma cultura Lean sustentável? Este contributo para o debate académico sobre a aplicação do Lean na Saúde introduz clareza sobre o que pode ou não ser chamado de práticas Lean na Saúde tendo como referência os conceitos dos fundadores; que padrão de implementação é seguido pelas organizações; e de que forma diferentes contextos culturais (nacionais e organizacionais) influenciam o ritmo desse padrão de implementação.

Abstract
Direct methods are becoming the most used technique to solve nonlinear optimal control problems. Regular time meshes having equidistant spacing are frequently used. However, in some cases these meshes cannot cope accurately with nonlinear behavior. One way to improve the solution is to select a new mesh with a greater number of nodes. Another way, involves adaptive mesh refinement. In this case, the mesh nodes have non equidistant spacing which allow a non uniform nodes collocation. In the method presented in this paper, a time mesh refinement strategy based on the local error is developed. After computing a solution in a coarse mesh, the local error is evaluated, which gives information about the subintervals of time domain where refinement is needed. This procedure is repeated until the local error reaches a user-specified threshold. The technique is applied to solve the car-like vehicle problem aiming minimum consumption. The approach developed in this paper leads to results with greater accuracy and yet with lower overall computational time as compared to using a time meshes having equidistant spacing.

Abstract
Maximizing the performance of cooperative perception of a tracked target by a team of mobile robots while maintaining the team's formation is the core problem addressed in this work. We propose a solution by integrating the controller and the estimator modules in a formation control loop. The controller module is a distributed non-linear model predictive controller and the estimator module is based on a particle filter for cooperative target tracking. A formal description of the integration followed by simulation and real robot results on two different teams of homogeneous robots are presented. The results highlight how our method successfully enables a team of homogeneous robots to minimize the total uncertainty of the tracked target's cooperative estimate while complying with the performance criteria such as keeping a pre-set distance between the team-mates and/or the target and obstacle avoidance.