Materials research by nuclear reaction analysis

This article is about computer simulation for surface analysis through nuclear techniques, which are non-destructive. The energy analysis method is used. Energy spectra are computer simulated and compared to experimental data, giving sample composition and concentration profiles. The method is successfully applied to depth profiling of 12C nuclei in a thick target, using the 12C(d,p0)13C deuteron induced reaction. Scanning electron microscopy is used as a complementary technique, to give information about surface topography.University of Beira Interiorinfo:eu-repo/semantics/publishedVersio

Materials research by elastic scattering analysis

This article is about computer simulation for surface analysis through nuclear techniques, which are non-destructive. The energy analysis method is used. Energy spectra are computer simulated and compared to experimental data, giving sample composition and concentration profiles. The method, using elastic scattering of (4He)+ ions, is successfully applied to depth profiling in both thin and thick targets containing Al and O.University of Beira Interior.info:eu-repo/semantics/publishedVersio

Performance Research on IEEE 802.11a 54 Mbps WPA2 Laboratory Links

The increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, resulting in more reliable and efficient communications. Security is also crucially important. Laboratory measurements are presented about several performance aspects of Wi-Fi IEEE 802.11a 54 Mbps WPA2 point-to-point and point-to-multipoint links. Our study contributes to performance evaluation of this technology under WPA2 encryption, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New results are given from TCP and UDP experiments concerning TCP throughput versus TCP packet length, jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to corresponding results for Open links. Conclusions are drawn about the comparative performance of the links.University of Beira Interiorinfo:eu-repo/semantics/publishedVersio

Nuclear Reaction Analysis of Materials using MeV Ion Beams

This article is about computer simulation for surface analysis through nuclear techniques, which are non-destructive. The energy analysis method is used. Energy spectra are computer simulated and compared to experimental data, giving sample composition and concentration profiles. The method is successfully applied to depth profiling of light nuclei e. g. 12C and 18O in thick targets, using deuteron and proton induced reactions, respectively. Scanning electron microscopy is used as a complementary technique, to give information about surface topography.University of Beira Interiorinfo:eu-repo/semantics/publishedVersio

Surface Analysis of Materials by Elastic Scattering of MeV Ions

Abstract—This article is about computer simulation for surface analysis through nuclear techniques, which are non-destructive. The energy analysis method is used. Energy spectra are computer simulated and compared to experimental data, giving sample composition and concentration profiles. The method, using elastic scattering of (4He)+ ions, is successfully applied to depth profiling in a target containing a thin film deposited on a thick substrate and in a thick target.University of Beira Interiorinfo:eu-repo/semantics/publishedVersio

Nuclear Techniques and Computer Simulation in Surface Analysis of Materials

This article is about computer simulation for surface analysis by nuclear techniques, which are non-destructive. The energy method of analysis is used for nuclear reactions and elastic scattering, as a particular and important case. Energy spectra are computer simulated and compared with experimental data, giving target composition and concentration profile information. The simulations use, mainly, target parameterization and available nuclear data. The method is applied to determination of an 18O concentration profile in a thick target using the 18O(p,α0)15N reaction. Elastic scattering of (4He)+ ions is applied to depth profiling of Al and Ag, Au thin films.University of Beira Interior.info:eu-repo/semantics/publishedVersio

Performance Evaluation of IEEE 802.11a 54 Mbps WEP Laboratory Links

The increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, resulting in more reliable and efficient communications. Security is also crucially important. Laboratory measurements are presented about several performance aspects of Wi-Fi IEEE 802.11a 54 Mbps WEP point-to-point and point-to-multipoint links. Our study contributes to performance evaluation of this technology under WEP encryption, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New results are given from TCP and UDP experiments concerning TCP throughput versus TCP packet length, jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to corresponding results for Open links. Conclusions are drawn about the comparative performance of the links.info:eu-repo/semantics/publishedVersio

Performance Research on IEEE 802.11 ac Laboratory Links

The increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, resulting in more reliable and efficient communications. Security is also crucially important. Laboratory measurements are presented about several performance aspects of Wi-Fi IEEE 802.11ac WPA2 point-to-point links. Our study contributes to performance evaluation of this technology under WPA2 encryption, using available equipments (Cisco 2702i access points and Edimax AC 1200 adapters). New results are given from TCP and UDP experiments concerning TCP throughput versus TCP packet length, jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to results obtained for corresponding IEEE 802.11n links. Conclusions are drawn about the comparative performance of the links.University of Beira Interiorinfo:eu-repo/semantics/acceptedVersio

Performance Evaluation of 5 GHz IEEE 802.11n WPA2 Laboratory Links

The increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a crucial issue, leading to more reliable and efficient communications. Security is also critically important. Laboratory measurements were performed about several performance aspects of Wi-Fi IEEE 802.11n WPA2 5 GHz links. Our study contributes to performance evaluation of this technology, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New detailed results are presented and discussed, namely at OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet length. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for both point-to-point and point-to-multipoint links. Comparisons are also made to corresponding results obtained for Open links. Conclusions are drawn about performance of the links.info:eu-repo/semantics/publishedVersio