6 research outputs found

    Standardization for Defence Procurement - European Handbook : CEN Workshop 10

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    The European Commission (EC), DG Enterprise, endeavours the competitiveness of the European Defence Industry. The plethora of (national) standards, more than 10.000, are recognised by the EC as a major constraint and cost driver. Electromagnetic Compatibility (EMC) or Electromagnetic Environmental Effects (EEE) are considered by the EC as a major topic, with 7 other topics such as environmental engineering, energetic materials, batteries, electrical interfaces. An EMC expert group with representatives from industry, including Aerotech Telub, Intellect, EADS, Ericsson Microwave, Fincantieri, MBDA, Thales, and national MoDs rationalized in 2004 a list of 329 EEE standards, implicitly abandoning national, including American, standards, and develop guidelines for the procurement process. A limited number of widely accepted and cost effective standards, suitable for use by MoD’s (acquisition) and industry (product development), has been defined after making comparisons. Comparisons were carried out on some standards against STANAG 4370 AECTP 500. The Expert Group agreed; That no one standard is better or worse than another in achieving an end goal. Differences are not sufficient to prevent the use of AECTP 500. There are sufficient similarities to AECTP 500 to adopt this as the fundamental replacement standard. There was sufficient agreement on NATO-, IEC- and EN-produced standards to make worthwhile agreement to use a number of standards as replacement for some (or some parts) of existing National Standards. This document gives recommendations on the use of the standards, the scope and \ud limitations. It also emphasizes the constraints with respect to the standardisation process of National MoD’s, NATO, Industry and EN/IEC

    Evaluating national guidelines for the prophylactic treatment of respiratory syncytial virus in children with congenital heart disease

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    Aim: This is the first study to evaluate compliance with the 2003 Swedish national guidelines for prophylactic treatment of respiratory syncytial virus (RSV) in children with congenital heart disease (CHD). We estimated the relative risk (RR) of children with CHD being hospitalised with a RSV infection, studied the extent to which RSV prophylactic treatment with palivizumab corresponded to the guidelines and determined the morbidity of children with CHD who developed RSV infection despite prophylaxis. Methods: This national observational study comprised prospectively registered data on 219 children with CHD treated with palivizumab, medical records on RSV cases and information on hospitalisation rates of children with CHD and RSV infection. Results: The calculated RR of children with CHD being hospitalised with RSV infection was 2.06 (950/0 Cl 1.6-2.6; p < 0.0001) compared with children without CHD. Approximately half of the patients (49%) born before the RSV season and 25% born during the RSV season did not start treatment as recommended by the guidelines. Conclusion: Having CHD increased the rate and estimated RR of children being hospitalised with RSV infection. The guidelines were not followed for about half of the children born before a RSV season and a quarter of the children born during a RSV season and need updating

    Avoiding Detection by Hostile Nodes in Airborne Tactical Networks

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    Contemporary airborne radio networks are usually implemented using omnidirectional antennas. Unfortunately, such networks suffer from disadvantages such as easy detection by hostile aircraft and potential information leakage. In this paper, we present a novel mobile ad hoc network (MANET) routing protocol based on directional antennas and situation awareness data that utilizes adaptive multihop routing to avoid sending information in directions where hostile nodes are present. Our protocol is implemented in the OMNEST simulator and evaluated using two realistic flight scenarios involving 8 and 24 aircraft, respectively. The results show that our protocol has significantly fewer leaked packets than comparative protocols, but at a slightly higher cost in terms of longer packet lifetime

    Respiratory Tract Infection and Risk of Hospitalization in Children with Congenital Heart Defects During Season and Off-Season : A Swedish National Study

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    Respiratory tract infections (RTI) are common among young children, and congenital heart defect (CHD) is a risk factor for severe illness and hospitalization. This study aims to assess the relative risk of hospitalization due to RTI in winter and summer seasons for different types of CHD. All children born in Sweden and under the age of two, in 2006–2011, were included. Heart defects were grouped according to type. Hospitalization rates for respiratory syncytial virus (RSV) infection and RTI in general were retrieved from the national inpatient registry. The relative risk of hospitalization was calculated by comparing each subgroup to other types of CHD and otherwise healthy children. The relative risk of hospitalization was increased for all CHD subgroups, and there was a greater increase in risk in summer for the most severe CHD. This included RSV infection, as well as RTI in general. The risk of hospitalization due to RTI is greater for CHD children. Prophylactic treatment with palivizumab, given to prevent severe RSV illness, is only recommended during winter. We argue that information to healthcare staff and parents should include how the risk of severe infectious respiratory tract illnesses, RSV and others, is present all year round for children with CHD

    Performance Assessment of OTFS Modulation in High Doppler Airborne Communication Networks

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    Emerging 5G and future 6G mobile networks are expected to cater for high mobility scenarios ranging from vehicle-to-vehicle communications to unmanned aerial vehicles and airborne platforms. Communications in this type of deployments suffer from severe Doppler shifts which require new modulation waveforms. Orthogonal time frequency space (OTFS) modulation has recently been proposed as a promising technology for coping with high Doppler channels. OTFS converts a time-varying fading channel into a time-independent channel in the two-dimensional delay-Doppler (DD) domain. The transmit symbols are multiplexed into a nearly constant channel with a complex channel gain in the DD domain. In this paper, we consider a high Doppler airborne communication network where relative mobile node speeds can be above 1200 m/s. The considered system represents a mobile ad-hoc network where the airborne mobile nodes can join or leave the network. Furthermore, each node is equipped with an antenna array that supports directed communication among mobile nodes. The Doppler shifts in this airborne communication network are in the order of 52-72 kHz and may potentially be even higher depending on the selected carrier frequency and the relative speed among the airborne platforms. As such, OTFS modulation is used in this work to efficiently compensate for the high Doppler shifts in the DD domain. In particular, a comprehensive performance assessment in terms of bit error rate (BER) is conducted to reveal the potential of OTFS modulation in dealing with such extreme transmission scenarios. The impact of physical layer parameters, number of delay-Doppler bins in the DD domain used for OTFS modulation, directed versus two-ray channels, and the combination of multiple-input multiple-output (MIMO) systems with OTFS modulation on the BER is assessed. It is shown that both OTFS modulation over a two-ray channel as well as MIMO-OTFS modulation provide a reliable airborne communication network with low BER. © 2022, The Author(s).open access</p
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