Search results for "Head"
showing 10 items of 1640 documents
Skull and Encephalic Injuries Caused by Beach Umbrellas: Case Reports and Review of Literature
2016
This study reports two unusual cases of skull-encephalic injuries in bathers that were caused by violent impacts with beach umbrellas. The first case concerned a 36-year-old man who, while lying on a sun bed, was struck on his left temple by a beach umbrella, which had been blown away by a gust of wind. The second case concerned a six-year-old child who was struck on the right temporal region while he was playing on the sand. Both subjects died. A review of the literature was carried out. Various skull and brain injuries caused by several objects were found, but no injuries caused by beach umbrellas were detected. There were only cases of injuries caused by normal umbrellas. These cases sho…
Mono and Stereoscopic Image Analysis for Detecting the Transverse Profile of Worn-Out Rails
2012
AbstractThe purpose of this paper is to suggest a new procedure for reconstructing the transverse profile of rails in operation by means of image-processing technique. This methodological approach is based on the “information” contained in high-resolution photographic images of tracks and on specific algorithms which allow to obtain the exact geometric profile of the rails and therefore to measure the state of the rail-head extrados wear. The analyses and the results concern rails taken from railway lines under upgrading by means of mono- and stereoscopic methods which are appropriate to be employed in laboratory applications or in high-efficiency surveys in situ.
Attenuation of low frequency magnetic fields produced by HV underground power cables
2015
High-voltage underground cable systems are becoming more common as the demand for electrical power within urban centers increase, also considering the difficulties in building new overhead power lines in the vicinity of city centers because of authorization issues. Therefore, interest towards the evaluation of magnetic fields produced by high-voltage power lines has been triggered during the last decade and concern about effects on human health of exposure to extra low frequency (ELF) magnetic fields due to power lines has been increasing as well. Hence, the evaluation of the magnetic field produced by underground power cables is important in order to develop methods for mitigating their in…
Optimization model predictions for postural coordination modes
2003
International audience; This paper examines the ability of the dynamic optimization model to predict changes between in-phase and anti-phase postural modes of coordination and to evaluate influence of two particular environmental and intentional constraints on postural strategy. The task studied was based on an experimental paradigm that consisted in tracking a target motion with the head. An original optimal procedure was developed for cyclic problems to calculate hip and ankle angular trajectories during postural sway with a minimum torque change criterion. Optimization results give a good description of the sudden bifurcation phase between in-phase and anti-phase postural coordination mo…
Ground-Fault Current Transfer at the Transition Station of a Combined Overhead-Cable Line. A Parametric Analysis
2007
When a substation is fed by a combined overhead-cable transmission line, a significant part of the ground fault current flows through the grounded cable sheaths and discharges into the earth at the transition station, where cables are connected to the overhead line. If the transition station is a dead-end steel pole structure, the local ground electrode, small and of high resistance, could be inadequate to maintain the ground potential rise within safety limits in case of a fault to ground at the receiving end substation. Based on a circuit model approach, the paper presents a parametric analysis of the fault current distribution between the faulted substation and the transition station, ta…
On the use of narrow band power line as communication technology for medium and low voltage smart grids
2012
The aim of this work is to perform a feasibility study on the power line communication for the development of a new generation of interface devices (IDs) for smart grid applications. More in detail, this paper deals with one of the most important issues on this topic which is the communication system. Among the existing communication technologies, the study is focused on power line communications (PLCs). After a analysis of the state of the art in the field, the main aspects are analyzed, concerning the open issues on the use of PLCs, especially for medium voltage (MV) and low voltage (LV) systems. In this work the use of PLC in MV-LV networks is investigated, by means of simulations and ex…
Mitigation of 50 Hz magnetic field produced by an overhead transmission line
2015
Power transmission utilities are challenged by the need to expand transmission system capacity to meet growing energy demands. The impact of high voltage overhead transmission lines on the environment represents a hot topic in the context of transport and distribution of electrical energy. In particular, interest towards the effects of extra low frequency (ELF) magnetic fields generated by high-voltage power transmission lines has been increasing significantly during the last decade, giving rise to a number of policy initiatives and research activities. Therefore, the evaluation of the magnetic field generated by conductors of overhead lines is of primary importance in order to develop meth…
An FPGA-Based Software Defined Radio Platform for the 2.4GHz ISM Band
2006
A prototype of a Software Defined Radio (SDR) platform has been successfully designed and tested implementing a reconfigurable IEEE 802.11 and ZigBee receiver. The system exploits the reconfiguration capability of an FPGA for implementing a number of receiver configurations that share the same RF front-end. Configurations can be switched at run time, or can share the available logic and radio resource.
Exploring the uncertainty in capacity estimation at roundabouts
2017
Abstract Purpose In gap-acceptance theory the critical and the follow-up headways have a significant role in determining roundabout entry capacities which in turn depend on circulating flow rates under a specified arrival headway distribution. Calculation considers single mean values of the gap-acceptance parameters, neglecting the inherent variations in these random variables and providing a single value of entry capacity. The purpose of this paper is to derive the entry capacity distribution which accounts for the variations of the contributing (random) variables and suggest how to consider this issue in the operational analysis of the roundabouts. Methods We performed a Monte Carlo simul…
Contribution to the platoon distribution analysis in steady-state traffic conditions
2014
The traffic flow analysis and the relevant vehicle distribution (“free-moving” or “platooned” vehicles) on highway facilities at uninterrupted flow has always had fundamental importance in Highway Engineering, with special reference to topics like traffic operations, car accidents, road safety and air pollution emissions. In light of this, the study suggests a calculation algorithm as a random test generator to simulate a steady state traffic flow and to provide time headways. Thanks to the outcome produced by numerical simulations, we analysed platoon distributions within traffic flows in a steady-state regime and showed the results of numerical analyses carried out by traffic random proce…