| 1. |
- Montelius, M., et al.
(author)
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Chemical evolution of ytterbium in the Galactic disk
- 2022
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 665
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Journal article (peer-reviewed)abstract
- Context. Measuring the abundances of neutron-capture elements in Galactic disk stars is an important part of understanding key stellar and galactic processes. In the optical wavelength regime a number of different neutron-capture elements have been measured; however, only the s-process-dominated element cerium has been accurately measured for a large sample of disk stars from the infrared H band. The more r-process dominated element ytterbium has only been measured in a small subset of stars so far. Aims. In this study we aim to measure the ytterbium (Yb) abundance of local disk giants using the Yb II line at lambda(air) = 16 498 angstrom. We also compare the resulting abundance trend with cerium and europium abundances for the same stars to analyse the s- and r-process contributions. Methods. We analyse 30 K giants with high-resolution H band spectra using spectral synthesis. The very same stars have already been analysed using high-resolution optical spectra via the same method, but it was not possible to determine the abundance of Yb from those spectra due to blending issues for stars with [Fe/H] > -1. In the present analysis, we utilise the stellar parameters determined from the optical analysis. Results. We determined the Yb abundances with an estimated uncertainty for [Yb/Fe] of 0.1 dex. By comparison, we found that the [Yb/Fe] trend closely follows the [Eu/Fe] trend and has clear s-process enrichment in identified s-rich stars. This comparison confirms both that the validity of the Yb abundances is ensured and that the theoretical prediction that the s-/r-process contribution to the origin of Yb of roughly 40/60 is supported. Conclusions. These results show that, with a careful and detailed analysis of infrared spectra, reliable Yb abundances can be derived for a wider sample of cooler giants in the range -1.1 < [Fe/H] < 0.3. This is promising for further studies of the production of Yb and for the r-process channel, key for galactochemical evolution, in the infrared.
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| 2. |
- Kebande, Victor R., Dr, et al.
(author)
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Holistic digital forensic readiness framework for IoT-enabled organizations
- 2020
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In: Forensic Science International: Reports. - : Elsevier. - 2665-9107. ; 2, s. 100117-100117
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Journal article (peer-reviewed)abstract
- Internet of Things (IoT) are becoming commonplace in homes, buildings, cities, and nations, and IoT networks are also getting more complex and interconnected. The complexity, interconnectivity, and heterogeneity of IoT systems, however, complicate digital (forensic) investigations. The challenge is compounded due to the lack of holistic and standardized approaches. Hence, building on the ISO/IEC 27043 international standard, we present a holistic digital forensic readiness (DFR) framework. We also qualitatively evaluate the utility of the proposed DFR framework.
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| 3. |
- Kebande, Victor R., et al.
(author)
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Mapping digital forensic application requirement specification to an international standard
- 2020
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In: Forensic Science International: Reports. - : Elsevier. - 2665-9107. ; 2
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Journal article (peer-reviewed)abstract
- A potential security incident may go unsolved if standardized forensic approaches are not applied during lawfulinvestigations. This paper highlights the importance of mapping the digital forensic application requirementspecification to an international standard, precisely ISO/IEC 27043. The outcome of this work is projected tocontribute to the problem of secure DF tool creation, and in the process address Software Requirements Specification(SRS) as a process of digital evidence admissibility.
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