7 resultados para dpi

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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A novel type of submicron ion radiography designed to image low-contrast objects, including nanofoils, membranes and biological structures, is proposed. It is based on femtosecond-laser-driven-cluster- plasma source of multicharged ions and polymer dosimeter film CR-39. The intense isotropic ion flow was produced by femtosecond Ti:Sa laser pulses with intensity similar to 4x10(17) W/cm(2) absorbed in the supersonic jet of the mixed He and CO2 gases. Two Focusing Spectrometers with Spatial Resolution (FSSR) were used to measure X-ray spectra of H-and He-like multicharged oxygen ions. The spectra testify that ions with energy more than 300 keV were radiated in different directions from the plasma source. High contrast ion radiography images were obtained for 2000 dpi metal mesh, 1 mu m polypropylene and 100 nm Zr foils as well as for the different biological objects. Images were recorded on a 1 mm thick CR-39 detector, placed in contact with back surface of the imaged samples at the distances 140 -160 mm from the ion source. The spatial resolution of the image no worse than 600 nm was provided. A difference in object thickness of 100 nm was very well resolved for both Zr and polymer foils. The ion radiography images recorded at different angles from the source, demonstrated almost uniform spatial distribution of ion with total number of 10(8) per shot. (C) 2009 WILEY-VCH Vertag GmbH & Co. KGaA, Weinheim

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The European Union Statistics of Income and Living Conditions
(EU-SILC) 2005 wave includes a special module on inter-generational
transmission of poverty. In addition to the standard data relating to income
and material deprivation, information relating to parental background and
childhood circumstances was collected for all household members aged over
24 and less than 66 at the end of the income reference period. In principle,
the module provides an unprecedented opportunity to apply a welfare regime
perspective to a comparative European analysis of the relationship between
poverty and social exclusion and parental characteristics and childhood
economic circumstances. In this paper, we seek to exploit such potential. In
pursuing this objective, it is necessary to take into account some of the
limitations of the data. We do by restricting our attention to a set of
countries where data issues seem less extreme. Finally, we compare findings
from one dimensional and multidimensional approaches to poverty and social
exclusion in order to provide an assessment of the extent to which our
analysis of welfare regime variation provides a coherent account of the
intergenerational transmission of disadvantage.

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Increased complexity and interconnectivity of Supervisory Control and Data Acquisition (SCADA) systems in Smart Grids potentially means greater susceptibility to malicious attackers. SCADA systems with legacy communication infrastructure have inherent cyber-security vulnerabilities as these systems were originally designed with little consideration of cyber threats. In order to improve cyber-security of SCADA networks, this paper presents a rule-based Intrusion Detection System (IDS) using a Deep Packet Inspection (DPI) method, which includes signature-based and model-based approaches tailored for SCADA systems. The proposed signature-based rules can accurately detect several known suspicious or malicious attacks. In addition, model-based detection is proposed as a complementary method to detect unknown attacks. Finally, proposed intrusion detection approaches for SCADA networks are implemented and verified using a ruled based method.

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Increased complexity and interconnectivity of Supervisory Control and Data Acquisition (SCADA) systems in Smart Grids potentially means greater susceptibility to malicious attackers. SCADA systems with legacy communication infrastructure have inherent cyber-security vulnerabilities as these systems were originally designed with little consideration of cyber threats. In order to improve cyber-security of SCADA networks, this paper presents a rule-based Intrusion Detection System (IDS) using a Deep Packet Inspection (DPI) method, which includes signature-based and model-based approaches tailored for SCADA systems. The proposed signature-based rules can accurately detect several known suspicious or malicious attacks. In addition, model-based detection is proposed as a complementary method to detect unknown attacks. Finally, proposed intrusion detection approaches for SCADA networks are implemented and verified via Snort rules.

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Cyber threats in Supervisory Control and Data Acquisition (SCADA) systems have the potential to render physical damage and jeopardize power system operation, safety and stability. SCADA systems were originally designed with little consideration of escalating cyber threats and hence the problem of how to develop robust intrusion detection technologies to tailor the requirements of SCADA is an emerging topic and a big challenge. This paper proposes a stateful Intrusion Detection System (IDS) using a Deep Packet Inspection (DPI) method to improve the cyber-security of SCADA systems using the IEC 60870-5-104 protocol which is tailored for basic telecontrol communications. The proposed stateful protocol analysis approach is presented that is designed specifically for the IEC 60870-5-104 protocol. Finally, the novel intrusion detection approach are implemented and validated.

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Chronic infection with Pseudomonas aeruginosa is associated with poor outcomes in patients with cystic fibrosis (CF). It leads to a reduced quality of life, acceleration of the decline in lung function, and increased frequency and severity of pulmonary exacerbations. Tobramycin, administered by inhalation as a long-term therapy, decreases bacterial density in airways, reduces exacerbation frequency, and improves quality of life and lung function in patients with chronic P. aeruginosa infection. In the last decade, tobramycin inhalation has become an important contributor to CF treatment as a means to control chronic infection and as a first-line treatment for the eradication of early acquisition of P. aeruginosa. Recently, a dry powder inhalation (DPI) form of tobramycin has become available, which is more convenient for administration and has comparable efficacy to the tobramycin solution. This DPI, the Podhaler™ (Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA), requires less time for treatment delivery and is more portable than a nebulizer, and so is a welcome additional therapeutic option for many patients.