Search results for "performance monitoring"

Plastic optical fibers for transmission and sensors

2005

This paper presents state and ways of development of plastic optical fibers (POF) for use in transmission-measuring devices for small area object networks (LAN networks in stationary and dynamic objects). Transmission links (with new fiber optics, simple optical components -- optical transmitters/receivers) allows nowadays transmission speed of a few Gb/s for a distance of hundreds meters. Properties and advantages of solutions based on plastic optical fiber for control, communication and managing are shown. Example practical solutions, regarding entering new standards and technologies, presents technical and economical advantages, compared to difficult and unfortunately expensive technolog…

All-Optical Polarization Control for Telecom Applications

2015

We describe a phenomenon of self-organization of the light state-of-polarization in optical fibers based on a nonlinear cross-polarization interaction between an incident signal and its backward replica. Several proof-of-principles for telecom applications are reported.

Optical flip-flop memory and data packet switching operation based on polarization bistability in a telecommunication optical fiber

2013

We report the experimental observation of bistability and hysteresis phenomena of the polarization signal in a telecommunication optical fiber. This process occurs in a counterpropagating configuration in which the optical beam nonlinearly interacts with its own Bragg-reflected replica at the fiber output. The proof of principle of optical flip–flop memory and 10  Gbit/s routing operation is also reported based on this polarization bistability. Finally, we also provide a general physical understanding of this behavior on the basis of a geometrical analysis of an effective model of the dynamics. Good quantitative agreement between theory and experiment is obtained.

Rateless Codes Performance Tests On Terrestrial FSO Time-Correlated Channel Model

2012

Free Space Optics (FSO) links are affected by several impairments: optical turbulence, scattering, absorption, and pointing. In particular, atmospheric optical turbulence generates optical power fluctuations at the receiver that can degrade communications with fading events, especially, in high data rate links. A way to mitigate FSO link outages can be to add a coding to communications. Nevertheless, in order to study innovative solutions (software or hardware) and to improve the FSO link performance it needs accurate testing models. In this paper we describe an accurate time-correlated channel model able to predict random temporal fluctuations of optical signal irradiance caused by optical…

A Model for a Data Acquisition Solution for a Medium Size Accelerator Laboratory

2005

Definition of criteria and indicators for the prevention of Healthcare-Associated Infections (HAIs) in hospitals for the purposes of Italian institut…

2017

Background. Healthcare-associated infections (HAIs) are an important issue in terms of quality of care. HAIs impact patient safety by contributing to higher rates of preventable mortality and prolonged hospita- lizations. In Italy, analysis of the currently available accreditation systems shows a substantial heteroge- neity of approaches for the prevention and surveillance of HAIs in hospitals. The aim of the present study is to develop and propose the use of a synthetic assessment tool that could be implemented homogenously throughout the nation. Methods. An analysis of nine international and of the 21 Italian regional accreditation systems was conducted in order to identify requirements a…

Optical wireless communication systems

2017

Abstract The emerging field of optical wireless communication (OWC) systems is seen as potential complementary technology to the radio frequency wireless communications in certain applications. It is deemed as a possible technology in the future 5th Generation communication networks to address the spectrum congestion and improve the system’s capacity. More research and developments in OWC is still needed in order for it to be adopted in current and future communication systems. This special issue brings together research papers on OWC covering free space optic, visible communications and ultraviolet communications.

All-optical measurement of residual chromatic dispersion and OSNR using self-phase modulation in optical fiber

2011

International audience; We describe a new all-fibered device providing high accuracy all-optical measurements of both optical signal to noise ratio and residual chromatic dispersion. Taking advantage of the self-phase modulation driven spectral evolution of pulses propagating in a highly non-linear medium, we have numerically and experimentally validated the benefits of using an anomalous dispersive fiber combined with a central spectral filtering.

Development of an individualized familiarization method for vertical jumps

2013

OBJETIVO: Propor um método de familiarização individualizado para saltos verticais e verificar o seu efeito na variabilidade intrassujeito. MÉTODOS: Cinquenta e três homes (média ± DP; idade 23,5 ± 3,3 anos; estatura 1,76 ± 0,08 m; massa 72,8 ± 8,6 kg; percentual de gordura 12,9 ± 5,2%) realizaram sucessivos saltos até atingir o nível de estabilidade proposto. Após 48 h este processo era repetido e a estabilidade entre dias era verificada, se necessário, mais sessões eram realizadas. O nível de estabilidade foi determinado por um teste z, com intervalo de confiança de 95%. Após o processo de familiarização, duas sessões experimentais adicionais foram realizadas para determinar a confiabilid…

Advanced performance monitoring for self-healing cellular mobile networks

2015

This dissertation is devoted to development and validation of advanced per- formance monitoring system for existing and future cellular mobile networks. Knowledge mining techniques are employed for analysis of user specific logs, collected with Minimization of Drive Tests (MDT) functionality. Ever increas- ing quality requirements, expansion of the mobile networks and their extend- ing heterogeneity, call for effective automatic means of performance monitoring. Nowadays, network operation is mostly controlled manually through aggregated key performance indicators and statistical profiles. These methods are are not able to fully address the dynamism and complexity of modern mobile networks. Se…