A Formal TLS Handshake Model in LNT

Testing of network services represents one of the biggest challenges in cyber security. Because new vulnerabilities are detected on a regular basis, more research is needed. These faults have their roots in the software development cycle or because of intrinsic leaks in the system specification. Conformance testing checks whether a system behaves according to its specification. Here model-based testing provides several methods for automated detection of shortcomings. The formal specification of a system behavior represents the starting point of the testing process. In this paper, a widely used cryptographic protocol is specified and tested for conformance with a test execution framework. The first empirical results are presented and discussed.Comment: In Proceedings MARS/VPT 2018, arXiv:1803.0866

Combining Spreadsheet Smells for Improved Fault Prediction

Spreadsheets are commonly used in organizations as a programming tool for business-related calculations and decision making. Since faults in spreadsheets can have severe business impacts, a number of approaches from general software engineering have been applied to spreadsheets in recent years, among them the concept of code smells. Smells can in particular be used for the task of fault prediction. An analysis of existing spreadsheet smells, however, revealed that the predictive power of individual smells can be limited. In this work we therefore propose a machine learning based approach which combines the predictions of individual smells by using an AdaBoost ensemble classifier. Experiments on two public datasets containing real-world spreadsheet faults show significant improvements in terms of fault prediction accuracy.Comment: 4 pages, 1 figure, to be published in 40th International Conference on Software Engineering: New Ideas and Emerging Results Trac

ENHANCED GLOBAL NUCLEAR EVENT LOCATION AND ITS UNCERTAINTY ANALYSIS BASED ON VARIOUS ADJOINT ENSEMBLE DISPERSION MODELLING TECHNIQUES

After the detection of treaty-relevant radionuclides in filters or air samples, atmospheric backtracking techniques are employed by the Provisional Technical Secretariat (PTS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) to trace back the measured substances to their potential areas of origin. In the case of an underground nuclear test, potential sources are co-located with the epicentres of seismic events that may have been triggered by the explosions. Previous studies have shown that predictions or analyses of atmospheric transport can be significantly improved by ensemble techniques. Within the CTBT environment it is important to build confidence in the source-receptor sensitivity (SRS) field based backtracking products issued by the PTS in the case of the occurrence of treaty relevant radionuclides. Therefore the PTS has set up a highly automated response system together with the Regional Specialized Meteorological Centres of the World Meteorological Organization in the field of dispersion modelling. These Centres have committed themselves to provide the PTS with the same standard SRS fields as calculated by their systems for CTBT relevant cases. The SRS field data standard allows for ensemble dispersion modelling. The parametric inter-comparison among ensemble members has been integrated into the decision making software tool WEB-GRAPE (CTBTO Newsletter Spectrum, 7, page 19). In sensitivity studies we varied the choice of LPDM, and the kind and source of wind field utilized to demonstrate the potential of the following two ensemble dispersion modelling (EDM) methods: a) Multi-model EDM in order to improve the accuracy of a global scale source attribution based on joint CTBTO-WMO experiments in January 2005 (Becker et al., 2007) and December 2007 (Wotawa and Becker, 2008). b) Single-model EDM with different lead times of the wind fields utilized in order to estimate the relative error of forecasted source attribution results in comparison to the analyzed ones c) Single-model EDM with different choices of wind field resolutions for the source receptor sensitivity fields of the same station at Schauinsland in order to assess quality of the PTS standard backtracking results based on the rather coarse 1º×1º horizontal resolution

ENHANCED GLOBAL NUCLEAR EVENT LOCATION AND ITS UNCERTAINTY ANALYSIS BASED ON VARIOUS ADJOINT ENSEMBLE DISPERSION MODELLING TECHNIQUES

After the detection of treaty-relevant radionuclides in filters or air samples, atmospheric backtracking techniques are employed by the Provisional Technical Secretariat (PTS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) to trace back the measured substances to their potential areas of origin. In the case of an underground nuclear test, potential sources are co-located with the epicentres of seismic events that may have been triggered by the explosions. Previous studies have shown that predictions or analyses of atmospheric transport can be significantly improved by ensemble techniques. Within the CTBT environment it is important to build confidence in the source-receptor sensitivity (SRS) field based backtracking products issued by the PTS in the case of the occurrence of treaty relevant radionuclides. Therefore the PTS has set up a highly automated response system together with the Regional Specialized Meteorological Centres of the World Meteorological Organization in the field of dispersion modelling. These Centres have committed themselves to provide the PTS with the same standard SRS fields as calculated by their systems for CTBT relevant cases. The SRS field data standard allows for ensemble dispersion modelling. The parametric inter-comparison among ensemble members has been integrated into the decision making software tool WEB-GRAPE (CTBTO Newsletter Spectrum, 7, page 19). In sensitivity studies we varied the choice of LPDM, and the kind and source of wind field utilized to demonstrate the potential of the following two ensemble dispersion modelling (EDM) methods: a) Multi-model EDM in order to improve the accuracy of a global scale source attribution based on joint CTBTO-WMO experiments in January 2005 (Becker et al., 2007) and December 2007 (Wotawa and Becker, 2008). b) Single-model EDM with different lead times of the wind fields utilized in order to estimate the relative error of forecasted source attribution results in comparison to the analyzed ones c) Single-model EDM with different choices of wind field resolutions for the source receptor sensitivity fields of the same station at Schauinsland in order to assess quality of the PTS standard backtracking results based on the rather coarse 1º×1º horizontal resolution

Anatomical connections in the human visual cortex: validation and new insights using a DTI Geodesic Connectivity Mapping method

Various approaches have been introduced to infer the organization of white matter connectivity using Diffusion Tensor Imaging (DTI). In this study, we validate a recently introduced geometric tractography technique, Geodesic Connectivity Mapping (GCM), able to overcome the main limitations of geometrical approaches. Using the GCM technique, we could successfully characterize anatomical connections in the human low-level visual cortex. We reproduce previous findings regarding the topology of optic radiations linking the LGN to V1 and the regular organization of splenium fibers with respect to their origin in the visual cortex. Moreover, our study brings further insights regarding the connectivity of the human MT complex (hMT+) and the retinotopic areas

Human Retinotopic Mapping Using fMRI

We present in this report a new method for the retinotopic mapping of the human visual cortex using fMRI. This fast method allow s to delineate any human's occipital retinotopic visual areas after 30 minutes in an MR scanner. Based on the known retinotopic properties o f the visual cortex and on the procedures described in the literature, we first detail the experimental protocol we used. We then present th e functional data analysis we perform to get the retinotopic angular maps. The algorithm to get a model of the cortical surface from the ana tomical MR image is also rapidly presented. We then show the retinotopic maps projected on the latter model and compare them with the litera ture. Lastly, we present the choices we made to delineate these areas and extract regions of interest that can be used for further studying the human visual cortical system

Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2

International audienceThe Lagrangian particle dispersion model FLEXPART was originally (about 8 years ago) designed for calculating the long-range and mesoscale dispersion of air pollutants from point sources, such as after an accident in a nuclear power plant. In the meantime FLEXPART has evolved into a comprehensive tool for atmospheric transport modeling and analysis. Its application fields were extended from air pollution studies to other topics where atmospheric transport plays a role (e.g., exchange between the stratosphere and troposphere, or the global water cycle). It has evolved into a true community model that is now being used by at least 25 groups from 14 different countries and is seeing both operational and research applications. A user manual has been kept actual over the years and was distributed over an internet page along with the model's source code. In this note we provide a citeable technical description of FLEXPART's latest version (6.2)