Abstract
Managing the physical and compute infrastructure of a large data center is an embodiment of a Cyber-Physical System (CPS). The physical parameters of the data center (such as power, temperature, pressure, humidity) are tightly coupled with computations, even more so in upcoming data centers, where the location of workloads can vary substantially due, for example, to workloads being moved in a cloud infrastructure hosted in the data center. In this paper, we describe a data collection and distribution architecture that enables gathering physical parameters of a large data center at a very high temporal and spatial resolution of the sensor measurements. We think this is an important characteristic to enable more accurate heat-flow models of the data center and with them, find opportunities to optimize energy consumption. Having a high resolution picture of the data center conditions, also enables minimizing local hotspots, perform more accurate predictive maintenance (pending failures in cooling and other infrastructure equipment can be more promptly detected) and more accurate billing. We detail this architecture and define the structure of the underlying messaging system that is used to collect and distribute the data. Finally, we show the results of a preliminary study of a typical data center radio environment.

Abstract
Optical characterization and internal structure of biological tissues is highly important for biomedical optics. In particular for optical clearing processes, such information is of vital importance to understand the mechanisms involved through the variation of the refractive indices of tissue components. The skeletal muscle presents a fibrous structure with an internal arrangement of muscle fiber cords surrounded by interstitial fluid that is responsible for strong light scattering. To determine the refractive index of muscle components we have used a simple method of measuring tissue mass and refractive index during dehydration. After performing measurements for natural and ten dehydration states of the muscle samples, we have determined the dependence between the refractive index of the muscle and its water content. Also, we have joined our measurements with some values reported in literature to perform some calculations that have permitted to determine the refractive index of the dried muscle fibers and their corresponding volume percentage inside the natural muscle.

Abstract
Ubiquitous Internet access is becoming a major requirement for end-users due to the increasing number of services and applications supported over the Internet. Extending the coverage of current Wi-Fi infrastructures installed in companies, universities and cities, has been considered a solution to help in fulfilling this requirement, namely when it comes to wireless and nomadic Internet access. This paper describes and analyses a new and simple solution, called Wi-Fi network Infrastructure eXtension (WiFIX), aimed at extending current Wi-Fi infrastructures. WiFIX is based on standard IEEE 802.1D bridges and a single-message protocol that is able to self-organize the network, and it only requires software changes in IEEE 802.11 access points (APs); no changes to IEEE 802.11 stations are needed. Overhead analysis and experimental results show both the higher efficiency of the solution compared to the IEEE 802.11s draft standard and its good performance as far as data throughput, delay and packet loss are concerned. Copyright (C) 2010 John Wiley & Sons, Ltd.

Abstract
DAPHNE (Developing Aircraft PHotonic NEtworks) is a 3-year European FP7 project (started September 2009). The aim of DAPHNE is to exploit terrestrial optical networking technology (with associated performance advantages) in future aircraft and systems. The consortium comprises fifteen partners (from seven nations) ranging from major air framers (both fixed and rotary wing) through component and equipment manufacturers and leading European universities. The project is coordinated by Airbus. © 2011 IEEE.

Abstract
We discuss recent developments in signal processing techniques for post-compensation of fiber dispersion and nonlinear distortion in both coherent and radio-over-fiber optical systems.

Abstract
One compact printed monopole antenna with a chip inductor for dual-band WLAN is presented. The proposed antenna has a two-armed structure and an electrically small size. The equivalent circuit structure of the chip inductor is studied and a simplified circuit structure is proposed. This simplified circuit structure was introduced into the electromagnetic (EM) simulation model by assigning a boundary condition, and the experimental results show that with this model, the simulation can provide an accurate prediction of the antenna radiation performance. The measurement results show that the proposed monopole antenna has a VSWR 2: 1 bandwidth over 2.41-2.49 and 5.2-5.6 GHz with omnidirectional radiation patterns. The simulation results suggest that the proposed antenna has a directivity around 1.5 dB at both bands with relatively high radiation efficiency. The antenna is designed and optimized by using Ansoft HFSS.