Abstract

Abstract
A spectral calibration technique, a data processing method and the importance of calibration and re-sampling methods for the spectral domain optical coherence tomography system were numerically studied, targeted to optical coherence tomography (OCT) signal processing implementation under graphics processing unit (GPU) architecture. Accurately, assigning the wavelength to each pixel of the detector is of paramount importance to obtain high quality images and increase signal to noise ratio (SNR). High quality imaging can be achieved by proper calibration methods, here performed by phase calibration and interpolation. SNR was assessed employing two approaches, single spectrum moving window averaging and consecutive spectra data averaging, to investigate the optimized method and factor for background noise reduction. It was demonstrated that the consecutive spectra averaging had better SNR performance. © 2012 The Author(s).

Abstract
This paper presents an overview of optical fiber sensors based on Fabry-Perot interferometers with a focus on high temperature applications. The next generation of these fiber types interferometers are based in photonic crystal fibers, microfabrication as well as by chemical etching of special structures. High temperature measurements with linear behavior are observed namely in un-doped fibers, i.e., with a pure silica composition. Three new configurations are presented as possible solutions to be considered in extreme conditions.

Abstract
During the last few years, the demand for Real-Time (RT) communication has been steadily increasing due to a wide range of new applications. Remarkable examples are VoIP (Voice over IP) and Networked Control Systems (NCS). For such RT applications, the support of timely communication services is one of the major requirements. The purpose of this chapter is to survey the state-of-the-art on RT communication in CSMA-based networks and to identify the most suitable approaches to deal with the requirements imposed by next generation communication systems. This chapter focuses on one of the most relevant solutions that operate in shared broadcast environments, according to the CSMA medium access protocol, the IEEE 802.11 standard. From this survey, it becomes clear that traditional CSMA-based networks are not able to deal with the requirements imposed by next generation communication systems. More specifically, they are not able to handle uncontrolled traffic sources sharing the same broadcast environment. © 2013, IGI Global.

Abstract
Many aspects of the human experience of ubiquitous computing in built environments must be explored in the context of the target environment. However, delaying evaluation until a version of the system can be deployed can make redesign too costly. Prototypes have the potential to solve this problem by enabling evaluation before actual deployment. This paper presents a study of the design space of immersive prototyping for ubiquitous computing. It provides a framework to guide the alignment between specific evaluation goals and specific prototype properties. The goal is to understand the potential added-value of 3D simulation as a prototyping tool in the development process of ubiquitous computing environments. © 2013 Springer-Verlag.

Abstract
Checking language equivalence (or inclusion) of finite automata is a classical problem in Computer Science, which has recently received a renewed interest and found novel and more effective solutions, such as approaches based on antichains or bisimulations up-to. Several notions of equivalence (or preorder) have been proposed for the analysis of concurrent systems. Usually, the problem of checking these equivalences is reduced to checking bisimilarity. In this paper, we take a different approach and propose to adapt algorithms for language equivalence to check one prime equivalence in concurrency theory, must testing semantics. To achieve this transfer of technology from language to must semantics, we take a coalgebraic outlook at the problem. © Springer International Publishing 2013.