Towards a Management Plane for Smart Contracts: Ethereum Case Study

in NOMS 2018 - 2018 IEEE/IFIP Network Operations and Management Symposium (2018)

Blockchain is an emerging foundational technology with the potential to create a novel economic and social system. The complexity of the technology poses many challenges and foremost amongst these are ... [more ▼]

Blockchain is an emerging foundational technology with the potential to create a novel economic and social system. The complexity of the technology poses many challenges and foremost amongst these are monitoring and management of blockchain-based decentralized applications. In this paper, we design, implement and evaluate a novel system to enable management operations in smart contracts. A key aspect of our system is that it facilitates the integration of these operations through dedicated ’managing’ smart contracts to provide data filtering as per the role of the smart contract-based application user. We evaluate the overhead costs of such data filtering operations after post-deployment analyses of five categories of smart contracts on the Ethereum public testnet, Rinkeby. We also build a monitoring tool to display public blockchain data using a dashboard coupled with a notification mechanism of any changes in private data to the administrator of the monitored decentralized application. [less ▲]

"Du récit d'enfance au roman de l'écrivain: schacko klak de Roger Manderscheid et la Mémoire de la baleine de Jean Portante"

in Les cahiers luxembourgeois (2018), 2

Monitoring the transaction selection policy of Bitcoin mining pools

in NOMS 2018 - 2018 IEEE/IFIP Network Operations and Management Symposium (2018)

Mining pools are collection of workers that work together as a group in order to collaborate in the proof of work and reduce the variance of their rewards when mining. In order to achieve this, Mining ... [more ▼]

Mining pools are collection of workers that work together as a group in order to collaborate in the proof of work and reduce the variance of their rewards when mining. In order to achieve this, Mining pools distribute amongst the workers the task of finding a block so that each worker works on a different subset of the candidate solutions. In most mining pools the selection of transactions to be part of the next block is performed by the pool manager and thus becomes more centralized. A mining Pool is expected to give priority to the most lucrative transactions in order to increase the block reward however changes to the transaction policy done without notification of workers would be difficult to detect. In this paper we treat the transaction selection policy performed by miners as a classification problem; for each block we create a dataset, separate them by mining pool and apply feature selection techniques to extract a vector of importance for each feature. We then track variations in feature importance as new blocks arrive and show using a generated scenario how a change in policy by a mining pool could be detected. [less ▲]

A Parallel Multiscale DEM-VOF Method For Large-Scale Simulations Of Three-Phase Flows

in Proceedings of ECCM-ECFD 2018 (2018)

A parallel dual-grid multiscale DEM-VOF coupling is here investigated. Dual- grid multiscale couplings have been recently used to address different engineering problems involving the interaction between ... [more ▼]

A parallel dual-grid multiscale DEM-VOF coupling is here investigated. Dual- grid multiscale couplings have been recently used to address different engineering problems involving the interaction between granular phases and complex fluid flows. Nevertheless, previous studies did not focus on the parallel performance of such a coupling and were, therefore, limited to relatively small applications. In this contribution, we propose an insight into the performance of the dual-grid multiscale DEM-VOF method for three- phase flows when operated in parallel. In particular,we focus on a famous benchmark case for three-phase flows and assess the influence of the partitioning algorithm on the scalability of the dual-grid algorithm. [less ▲]

Helical light emission from plasmonic vortices via magnetic tapered tip

in Journal of Physics. Conference Series (2018), 961

We investigate an architecture where a plasmonic vortex excited in a gold surface propagates on an adiabatically tapered magnetic tip and detaches to the far-field while carrying a well-defined optical ... [more ▼]

We investigate an architecture where a plasmonic vortex excited in a gold surface propagates on an adiabatically tapered magnetic tip and detaches to the far-field while carrying a well-defined optical angular momentum. We analyze the out-coming light and show that, despite generally high losses of flat magnetic surface, our 3D structure exhibits high energy throughput. Moreover, we show that once a magneto-optical activity is activated inside the magnetic tip a modulation of the total power transmittance is possible. [less ▲]

Editionsphilologie und inszenierende Typographie: eine praxeologische Perspektive auf die 'Mein-Kampf'-Edition des Instituts für Zeitgeschichte

in Editio: Internationales Jahrbuch für Editionswissenschaft (2018), 32

Elliptic Curves Discrete Logarithm Problem over a Finite Field Fp and p-adic Approximations

in Proceedings of the 3rd International Conference on Applications in Information Technology (ICAIT-2018) (2018)

These notes summarize some computations conducted around the Elliptic Curves Discrete Logarithm Problem (ECDLP) over a finite field Fp.

Development of a Control Strategy for a PVT-based CO2 Heat Pump

in Proceedings of 7th International Energy and Sustainability Conference (IESC) (2018)

In recent years, the possibility of combining photovoltaics (PV) and solar thermal collectors into one solar hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and ... [more ▼]

In recent years, the possibility of combining photovoltaics (PV) and solar thermal collectors into one solar hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and electrical energy at the same time. Since the efficiency of a photovoltaic module decreases with increasing temperature, the temperature of the heat transfer media is often limited to about 30 °C and the PVT-module is combined with a heat pump, which increases the temperature on the “warm side”. A common approach is to integrate the PVT-module directly as an evaporator in a heat pump system (PVT-direct). This paper presents the development of a control strategy for a PVT-based CO2 heat pump that takes into account solar radiation, ambient temperature, wind speed, evaporator temperature and compressor power. The developed control strategy provides different operating modes depending on the solar radiation supply as well as the ambient temperature. [less ▲]

Blockchain Technology - Arsenal for a Shariah-Compliant Financial Ecosystem

in Journal of Business and Economics (2017, December 05)

The authors’ first challenge is to decipher the complexity of Islamic Finance despite the opacity of the sector. A second focal point is the agent’s agenda; in the Islamic Finance industry, contributors ... [more ▼]

The authors’ first challenge is to decipher the complexity of Islamic Finance despite the opacity of the sector. A second focal point is the agent’s agenda; in the Islamic Finance industry, contributors mandate intermediaries (agents) to transfer their contributions to social causes according to the Shariah; in principle, Islamic financial institutions must create value for their stakeholders by offering Shariah-compliant products and services. An underlying assumption of agency theory is that agents attempt to maximize their personal welfare and compensation, but such behaviour may not always be in the best interests of other stakeholders, and an analysis of the agent’s agenda can help explain how agents can fall off the pedestal of altruism. Relationships between Islamic banks and three key stakeholders (contributors, beneficiaries and regulators) are also explored via a complexity-aware monitoring process. Contributors provide funds to an Islamic bank (agent), and in return, the agent should be accountable to the contributors, but the form and degree of accountability can vary depending on the organization’s mission. There are many unanswered questions regarding the monitoring process. One objective of the article is to consider whether agents act in the best interests of the stakeholders. Finally, the authors explore the following question: Can blockchain technology and smart contracts support and enhance the transparency feature, which is the core underlying principle of all transactions in the Islamic Finance industry? A qualitative research framework was adopted because of the constraints of the enigmatic, secretive Islamic Finance culture. [less ▲]

Cache-Assisted Hybrid Satellite-Terrestrial Backhauling for 5G Cellular Networks

in Proceedings of IEEE Global Communications Conference (2017, December)

Fast growth of Internet content and availability of electronic devices such as smart phones and laptops has created an explosive content demand. As one of the 5G technology enablers, caching is a ... [more ▼]

Fast growth of Internet content and availability of electronic devices such as smart phones and laptops has created an explosive content demand. As one of the 5G technology enablers, caching is a promising technique to off-load the network backhaul and reduce the content delivery delay. Satellite communications provides immense area coverage and high data rate, hence, it can be used for large-scale content placement in the caches. In this work, we propose using hybrid mono/multi-beam satellite-terrestrial backhaul network for off-line edge caching of cellular base stations in order to reduce the traffic of terrestrial network. The off-line caching approach is comprised of content placement and content delivery phases. The content placement phase is performed based on local and global content popularities assuming that the content popularity follows Zipf-like distribution. In addition, we propose an approach to generate local content popularities based on a reference Zipf-like distribution to keep the correlation of content popularity. Simulation results show that the hybrid satellite-terrestrial architecture considerably reduces the content placement time while sustaining the cache hit ratio quite close to the upper-bound compared to the satellite-only method. [less ▲]

Early Onset Epileptic Encephalopathy: Genetic Analysis and Further Delineation of Genotype-phenotype Correlation

in Annals of Neurology (2017, October), 82(SI), 295-296

Objective: Early onset epileptic encephalopathy (EOEE)remains an important diagnostic and therapeutic challenge.The objective was to perform genetic analysis in patientswith EOEE and to further delineate ... [more ▼]

Objective: Early onset epileptic encephalopathy (EOEE)remains an important diagnostic and therapeutic challenge.The objective was to perform genetic analysis in patientswith EOEE and to further delineate the genotype-phenotype correlation in patients with EOEE. Methods: We recruited 15 refractory epileptic patientswith epileptic onset before age 12 months. All patients had metabolic screening, electroencephalogram, magnetic reso-nance imaging and molecular analysis (comparative genomic hybridization, gene sequencing, next generation sequencing and or whole exome sequencing. Results: Dravet syndrome (DS) with SCN1A mutations was found in six patients with refractory epilepsy (RE) andmoderate to severe developmental delay (DD). Two patients diagnosed (KCNT1, SCN) with malignant migrating partialseizure (MMPS) had RE, severe DD, autistic behavior. The latter had movement disorders (video) (choreoathetosis, ballis-mus) with a worse outcome than the patients with DS phe-notype with SCN1A mutations. Severe DD and RE wasfound in patients with SCN8A, SLC13A5, SMC1A, orHCFC1 and ATRX mutations. Patient with SCN2A mutation had severe DD. A better outcome was observed in the patient with CDKL5 mutations in the catalytic domain in compari-son with the patient with a deletion in Xp22.13 including CDKL5. The patient with SMC1A mutations disclosed the Cornelia de Lange syndrome phenotype (Table 1). TRXmutations and deletions in 2q24.3 and Xp22.13. In SLC13A5 and SCN2A mutations, epileptic onset occurred atthe earliest age. [less ▲]

How Could an Intranet be Like a Friend to Me?: Why Standardized UX Scales Don't Always Fit

in Proceedings of the European Conference on Cognitive Ergonomics 2017 (2017, October)

"I hope that this survey is a joke because it made me laugh so much". This quote is just one example of many negative respondents' reactions gathered during a large-scale user experience (UX) study ... [more ▼]

"I hope that this survey is a joke because it made me laugh so much". This quote is just one example of many negative respondents' reactions gathered during a large-scale user experience (UX) study. Unfortunately, the survey was no joke, rather a well-constructed and validated standardized UX scale. This paper critically reflects on the use and relevance of standardized UX scales for the evaluation of UX in business contexts. We report on a real-world use case where the meCUE questionnaire has been used to assess employees' experience (N=263) with their organization's intranet. Strong users' reactions to the survey's items and statistical analyses both suggest that the scale is unsuitable for the evaluation of business-oriented systems. Drawing on the description of this inadequacy, we discuss the quality of academic UX tools, calling into question the relevance for practice of academic methods. [less ▲]

Performance of a Non-Coherent Massive SIMO M-DPSK System

in IEEE 86th Vehicular Technology Conference (VTC-Fall) (2017, September)

Discretisation and Model Selection for Interface Problems in Mechanics

in International Journal of Computational Methods (2017, August 04)

Multi-antenna based one-bit spatio-temporal wideband sensing for cognitive radio networks

in Proceedings of IEEE International Conference on Communications (ICC) 2017 (2017, July 31)

Cognitive Radio (CR) communication has been considered as one of the promising technologies to enable dynamic spectrum sharing in the next generation of wireless networks. Among several possible enabling ... [more ▼]

Cognitive Radio (CR) communication has been considered as one of the promising technologies to enable dynamic spectrum sharing in the next generation of wireless networks. Among several possible enabling techniques, Spectrum Sensing (SS) is one of the key aspects for enabling opportunistic spectrum access in CR Networks (CRN). From practical perspectives, it is important to design low-complexity wideband CR receiver having low resolution Analog to Digital Converter (ADC) working at a reasonable sampling rate. In this context, this paper proposes a novel spatio-temporal wideband SS technique by employing multiple antennas and one-bit quantization at the CR node, which subsequently enables the use of a reasonable sampling rate. In our analysis, we show that for the same sensing performance requirements, the proposed wideband receiver can have lower power consumption than the conventional CR receiver equipped with a single-antenna and a high-resolution ADC. Furthermore, the proposed technique exploits the spatial dimension by estimating the direction of arrival of Primary User (PU) signals, which is not possible by the conventional SS methods and can be of a significant benefit in a CRN. Moreover, we evaluate the performance of the proposed technique and analyze the effects of one-bit quantization with the help of numerical results. [less ▲]

On the Unknown Input Functional Observer Design via Polytopic Lyapunov Function: Application to a Quadrotor Aerial Robots Landing

in IFAC-PapersOnLine (2017, July)

In this paper, a constructive procedure to design functional unknown input observer for nonlinear continuous time systems under the Polytopic Takagi-Sugeno framework (also known as multiple models systems ... [more ▼]

In this paper, a constructive procedure to design functional unknown input observer for nonlinear continuous time systems under the Polytopic Takagi-Sugeno framework (also known as multiple models systems) is proposed. Applying the Lyapunov theory, Linear Matrix Inequalities (LMI)s conditions are deduced which are solved for feasibility to obtain observer design matrices. To reject the effect of unknown input, classical approach of decoupling the unknown input for the linear case is used. A comparative study between single and Polytopic Lyapunov function is made in order to prove the relaxation effect of the Multiple functions. A solver based solution is then proposed. It will be shown through applicative example (a Quadrotor Aerial Robots Landing) that even if the proposed LMIs solver based solution may look conservative, an adequate choice of the solver makes it suitable for the application of the proposed approach. [less ▲]

Effectiveness of the Two-Step Dynamic Demand Estimation model on large networks

in Proceedings of 2017 5th IEEE International Conference on Models and Technologies for Intelligent Transportation Systems (MT-ITS) (2017, June 28)

In this paper, the authors present a Two-Step approach that sequentially adjusts generation and distribution values of the (dynamic) OD matrix. While the proposed methodology already provided excellent ... [more ▼]

In this paper, the authors present a Two-Step approach that sequentially adjusts generation and distribution values of the (dynamic) OD matrix. While the proposed methodology already provided excellent results for updating demand flows on a motorway, the aim of this paper is to validate this conclusion on a real network: Luxembourg City. This network represents the typical middle-sized European city in terms of network dimension. Moreover, Luxembourg City has the typical structure of a metropolitan area, composed of a city centre, ring, and suburb areas. An innovative element of this paper is to use mobile network data to create a time-dependent profile of the generated demand inside and outside the ring. To support the claim that the model is ready for practical implementation, it is interfaced with PTV Visum, one of the most widely adopted software tools for traffic analysis. Results of these experiments provide a solid empirical ground in order to further develop this model and to understand if its assumptions hold for urban scenarios. [less ▲]

Device-based assessment through a mobile application in the Luxembourg Parkinson Cohort

in Basal Ganglia (2017, May), 8

Introduction: The project focuses on the integration device-based assessment (DBA) with a mobile application (mPower) into the longitudinal deeply-phenotyped HELP-PD (Health in the Elderly Luxembourgish ... [more ▼]

Introduction: The project focuses on the integration device-based assessment (DBA) with a mobile application (mPower) into the longitudinal deeply-phenotyped HELP-PD (Health in the Elderly Luxembourgish Population with a focus on Parkinson’s disease) cohort for patients with Parkinsonism in Luxembourg and the Greater Region to monitor frequency and degree of variation in symptoms of Parkinsonism, to identify potential sources and modulators of variation and to evaluate how symptoms are correlated with these modulators across patients. Methods: We integrate for the first time the mPower iOS app into a deeply phenotyped cohort. mPower is one of the first apps to use Apple’s Research Kit framework and combines a traditional survey-based approach with more granular and precise data gained from a person’s iPhone related to sensor- (e.g. step count, GPS-tracking) or task-based assessments (e.g. finger tapping, tremor detection, sustained phonation, simple gait analysis, memory test). Anonymized longitudinal data is sent to a repository, then retrieved, matched, and correlated with conventional HELP-PD data from a total of 47 screening instruments for motor and non-motor functions in Parkinsonism obtained from annual visits of study participants. 14 patients with clinically confirmed IPD are currently included in the pilot phase. Results/Discussion: We modified the mPower app and successfully integrated it into HELP-PD’s novel database infrastructure, allowing for a wide variety of analyses. The reporting system is able to handle multiple DBAs, with the implementation of an in-depth gait analysis system currently pending. Considerable attention was given to data protection. The system is currently fully functional with the pilot phase having started in June 2016. First correlations with traditional clinical data are planned for early 2017. [less ▲]

On the Diversity of Partial Relaying Cooperation with Relay Selection in Finite-SNR Regime

in IEEE International Conference on Communications (2017, May)

Unknown Input Functional Observers Design for Polytopic Discrete Time Systems

in Proceedings of 6th IEEE International Conference on Systems and Control (ICSC) 2017 (2017, May)

In this paper, a step by step algorithm is given to design functional unknown input observer for nonlinear discrete time systems under the Polytopic Takagi-Sugeno framework (also known as multiple models ... [more ▼]

In this paper, a step by step algorithm is given to design functional unknown input observer for nonlinear discrete time systems under the Polytopic Takagi-Sugeno framework (also known as multiple models systems). Applying the Lyapunov theory and the L2 attenuation, Linear Matrix Inequalities (LMI)s conditions are deduced which are solved for feasibility to obtain observer design matrices. To reject the effect of unknown input, classical approach of decoupling the unknown input for the linear case is used. A solver based solution is proposed. The novelty of the proposed approach consists in solving simultaneously both structural constraints and LMIs, which ensure a mean for the efficient design of the gains of the observers. To illustrate the proposed theoretical results, an application example of model reference tracking control applied to an electro-mechanical model of a motor with a time varying parameter is discussed. [less ▲]

Detecting the "Big Red Spot" of age-period excess mortality in 25 countries: Age-period-cohort residual analysis

in PAA Server (2017, April 28)

In times of wide availability of yearly mortality information of age and period groups all over the world, we lack in tools that detect and graph fine-grained deviations from mortality trends. We provide ... [more ▼]

In times of wide availability of yearly mortality information of age and period groups all over the world, we lack in tools that detect and graph fine-grained deviations from mortality trends. We provide a new age-period-cohort based methodology, combining information from age-period (AP) and APC-Detrended (APCD) analyses to detect all-cause mortality increases. Plotting the resulting AP coefficients and APCD residuals in equilateral Lexis diagrams, mortality patterns can easily be distinguished as age, period, or cohort trends and fluctuations. Additionally, we detect abnormalities as interactions of age and period (‘big red spots’). We then investigate the ‘red spots’ of mortality of young-adult cohorts in the early 1990s in Spain, other southern European countries and the U.S. to delineate their simultaneously occurring public health crises. Additional analyses with WHO mortality data show that mortality increases are mostly due to increased HIV/AIDS mortality. We discuss possible applications of the new method. [less ▲]

Toward an in-depth understanding of binge-watching behavior: a qualitative approach with focus group

in Journal of behavioral addictions (2017, March), 6 (Suppl.1)

Stationary Wavelet Transform for denoising Pulsed Thermography data: optimization of wavelet parameters for enhancing defects detection

in Quantitative Infra Red Thermography Journal (2017)

Innovative denoising techniques based on Stationary Wavelet Transform (SWT) have started being applied to Pulsed Thermography (PT) sequences, showing marked potentialities in improving defect detection ... [more ▼]

Innovative denoising techniques based on Stationary Wavelet Transform (SWT) have started being applied to Pulsed Thermography (PT) sequences, showing marked potentialities in improving defect detection. In this contribution, a SWT-based denoising procedure is performed on high and low resolution PT sequences. Samples under test are two composite panels with known defects. The denoising procedure undergoes an optimization step. An innovative criterion for selecting the optimal decomposition level in multi-scale SWT-based denoising is proposed. The approach is based on a comparison, in the wavelet domain, of the information content in the thermal image with noise propagated. The optimal wavelet basis is selected according to two performance indexes, respectively based on the probability distribution of the information content of the denoised frame, and on the Energy-to-Shannon Entropy ratio. After the optimization step, denoising is applied on the whole thermal sequence. The approximation coefficients at the optimal level are moved to the frequency domain, then low-pass filtered. Linear Minimum Mean Square Error (LMMSE) is applied to detail coefficients at the optimal level. Finally, Pulsed Phase Thermography (PPT) is performed. The performance of the optimized denoising method in improving the defect detection capability respect to the non-denoised case is quantified using the Contrast Noise Ratio (CNR) criterion. [less ▲]

Novel C-ITS support for Electric Buses with Opportunity Charging

in Proceedings of IEEE-ITS Conference (2017)

Confirmation Delay Prediction of Transactions in the Bitcoin Network

in Lecture Notes in Electrical Engineering (2017)

Bitcoin is currently the most popular digital currency. It operates on a decentralised peer-to-peer network using an open source cryptographic protocol. In this work, we create a model of the selection ... [more ▼]

Bitcoin is currently the most popular digital currency. It operates on a decentralised peer-to-peer network using an open source cryptographic protocol. In this work, we create a model of the selection process performed by mining pools on the set of unconfirmed transactions and then attempt to predict if an unconfirmed transaction will be part of the next block by treating it as a supervised classification problem. We identified a vector of features obtained through service monitoring of the Bitcoin transaction network and performed our experiments on a publicly available dataset of Bitcoin transaction. [less ▲]

IDENTIFICATION OF A RARE GENE VARIANT THAT IS ASSOCIATED WITH FAMILIAL ALZHEIMER DISEASE AND REGULATES APP EXPRESSION

in Alzheimer's and Dementia: the Journal of the Alzheimer's Association (2017), 13(7, Supplement), 648

Background Genetic mutations leading to familial forms of Alzheimer disease (AD) have so far been reported for a few genes including APP, PSEN1 and PSEN2, UNC5C, PLD3, ABCA7, TTC3, and possibly ADAM10 ... [more ▼]

Background Genetic mutations leading to familial forms of Alzheimer disease (AD) have so far been reported for a few genes including APP, PSEN1 and PSEN2, UNC5C, PLD3, ABCA7, TTC3, and possibly ADAM10. With the advent of whole exome and whole genome sequencing approaches new genes and mutations are likely to be identified. Methods We analyzed the genetic cause of AD in a large multiplex family with an autosomal-dominant pattern of inheritance with LOAD. The family lacked pathogenic mutations of known AD genes. We performed whole-genome sequencing (WGS) in six family members (two affected and four unaffected) and prioritized rare, potential damaging, variants that segregated with disease. Variants were further characterized by subsequent molecular analyzes in human brain and cell culture models. Results We identified a single rare nonsynonymous variant co-segregating with AD. The mutation inhibits pro-protein cleavage and the formation of the active enzyme, thus leading to a loss-of-function of the gene. We further found a strong negative correlation between the identified gene and APP gene expression in human brain and in cells over-expressing the gene. The negative regulation of APP expression was only observed for the wt gene, but not for mutated forms, thus causing beside the loss of enzyme function a decoupling of both APPexpression and subsequent beta-amyloid formation. The identity of the gene will be presented on the conference. Conclusions This novel pathway strongly supports a causative association of the identified gene with the pathogenesis of AD. [less ▲]

On characterizing the relationship between route choice behavior and optimal traffic control solution space

in Transportation Research Procedia (2017), 23

Explicitly including the dynamics of users' route choice behaviour in optimal traffic control applications has been of interest for researchers in the last five decades. This has been recognized as a very ... [more ▼]

Explicitly including the dynamics of users' route choice behaviour in optimal traffic control applications has been of interest for researchers in the last five decades. This has been recognized as a very challenging problem, due to the added layer of complexity and the considerable non-convexity of the resulting problem, even when dealing with simple static assignment and analytical link cost functions. In this work we establish a direct behavioural connection between the different shapes and structures emerging in the solution space of such problems and the underlying route choice behaviour. We specifically investigate how changes in the active equilibrium route set exert direct influence on the solution space's structure and behaviour. Based on this result, we then formulate and validate a constrained version of the original problem, yielding desirable properties in terms of solution space regularity. © 2017 The Authors. [less ▲]

Board Game Prototyping to Co-Design a Better Location-Based Digital Game

in Abstract book of the 2017 CHI Conference Extended Abstracts on Human Factors in Computing Systems - CHI EA '17 (2017)

In this case study we describe the iterative process of paper prototyping, using a board game, to co-design a location-based mobile application. The end goal of the application is to motivate reflection ... [more ▼]

In this case study we describe the iterative process of paper prototyping, using a board game, to co-design a location-based mobile application. The end goal of the application is to motivate reflection on historical topics about migration. The board game serves to capture the core concerns of this application by simulating movement through the city. Three play tests highlighted the users' interest and issues with the historical content, the way this content is represented, and the players' responses to the interactions and motivating mechanisms of the application. Results show that the board game helped capture important design preferences and problems, ensuring the improvement of our scenario. This feedback can help reduce development effort and implement a future technology prototype closer to the needs of our end users. [less ▲]

SimiDroid: Identifying and Explaining Similarities in Android Apps

in Abstract book of the 16th IEEE International Conference on Trust, Security and Privacy in Computing and Communications (TrustCom) (2017)

App updates and repackaging are recurrent in the Android ecosystem, filling markets with similar apps that must be identified and analysed to accelerate user adoption, improve development efforts, and ... [more ▼]

App updates and repackaging are recurrent in the Android ecosystem, filling markets with similar apps that must be identified and analysed to accelerate user adoption, improve development efforts, and prevent malware spreading. Despite the existence of several approaches to improve the scalability of detecting repackaged/cloned apps, researchers and practitioners are eventually faced with the need for a comprehensive pairwise comparison to understand and validate the similarities among apps. This paper describes the design of SimiDroid, a framework for multi-level comparison of Android apps. SimiDroid is built with the aim to support the understanding of similarities/changes among app versions and among repackaged apps. In particular, we demonstrate the need and usefulness of such a framework based on different case studies implementing different analysing scenarios for revealing various insights on how repackaged apps are built. We further show that the similarity comparison plugins implemented in SimiDroid yield more accurate results than the state-of-the-art. [less ▲]

Fast and optimal countermeasure selection for attack defence trees

in Lecture Notes in Computer Science (2017), 10224 LNCS

Risk treatment is an important part of risk management, and deals with the question which security controls shall be implemented in order to mitigate risk. Indeed, most notably when the mitigated risk is ... [more ▼]

Risk treatment is an important part of risk management, and deals with the question which security controls shall be implemented in order to mitigate risk. Indeed, most notably when the mitigated risk is low, the costs engendered by the implementation of a security control may exceed its benefits. The question becomes particularly interesting if there are several countermeasures to choose from. A promising candidate for modeling the effect of defensive mechanisms on a risk scenario are attack–defence trees. Such trees allow one to compute the risk of a scenario before and after the implementation of a security control, and thus to weigh its benefits against its costs. A naive approach for finding an optimal set of security controls is to try out all possible combinations. However, such a procedure quickly reaches its limits already for a small number of defences. This paper presents a novel branch-and-bound algorithm, which skips a large part of the combinations that cannot lead to an optimal solution. The performance is thereby increased by several orders of magnitude compared to the pure brute–force version. © 2017, Springer International Publishing AG. [less ▲]

L’idée de civilisation dans la pratique conventionnelle des États occidentaux aux XIXe et XXe siècles

in Droits: Revue français de théorie, de philosophie et de cultures juridiques (2017), (66), 37-55

Based on an analysis of more than 450 treaties and other international instruments, this article shows how the terms 'civilisation' or 'civilised' were used in 19th and 20th century state practice and how ... [more ▼]

Based on an analysis of more than 450 treaties and other international instruments, this article shows how the terms 'civilisation' or 'civilised' were used in 19th and 20th century state practice and how the meaning given to these terms evolved over time. [less ▲]

LES-VOF SIMULATIONS OF A PURE WATER JET DEVELOPING INSIDE AN AWJC NOZZLE: PRELIMINARY OBSERVATIONS AND GUIDELINES

in Proceedings of 2017 WJTA-IMCA (2017)

In this work, a numerical approach to predict the behavior of a pure water jet developing inside a nozzle for Abrasive Water Jet Cutting (AWJC) is investigated. In a standard AWJC configuration, the water ... [more ▼]

In this work, a numerical approach to predict the behavior of a pure water jet developing inside a nozzle for Abrasive Water Jet Cutting (AWJC) is investigated. In a standard AWJC configuration, the water jet carries the major energy content of the entire system, and is responsible for accelerating abrasive particles that will perform the cutting action of hard materials. Therefore an accurate simulation of a pure water jet can bring significant insight on the overall AWJC process. Capturing the behavior of a multiphase high-speed flow in a complex geometry is however particularly challenging. In this work, we adopt a combined approach based on the Volume of Fluid (VOF) and Large Eddy Simulation (LES) techniques in order to respectively capture the water/air interface and to model turbulent structures of the flow. The aim of this contribution is to investigate how the two techniques apply to the specific problem, and to offer general guidelines for practitioners willing to adopt them. Costs considerations will be then presented with particular reference to the usage of the OpenFOAM® environment. The reported results are meant to provide guidance for AWJ applications and future developments of AWJ nozzles. [less ▲]

On the Insecurity of a Method for Providing Secure and Private Fine-Grained Access to Outsourced Data

in Abstract book of 2016 IEEE 8th International Conference on Cloud Computing Technology and Science (CloudCom) (2016, December)

The protection of sensitive data stored in the cloud is paramount. Among the techniques proposed to provide protection, attribute-based access control, which frequently uses ciphertext-policy attribute ... [more ▼]

The protection of sensitive data stored in the cloud is paramount. Among the techniques proposed to provide protection, attribute-based access control, which frequently uses ciphertext-policy attribute-based encryption (CPABE), has received a lot of attention in the last years. Recently, Jahan et al.~(IEEE 40th Conference on Local Computer Networks, 2015) propose a scheme based on CPABE where users have reading and writing access to the outsourced data. We analyze the scheme by Jahan et al.\ and we show that it has several security vulnerabilities. For instance, the cloud server can get information about encrypted messages by using a stored ciphertext and an update of that ciphertext. As another example, users with writing access are able to decrypt all the messages regardless of their attributes. We discuss the security claims made by Jahan et al.\ and point out the reasons why they do not hold. We also explain that existing schemes can already provide the advantages claimed by Jahan et al. [less ▲]

Green exercise is associated with better cell ageing profiles

in The European Journal of Public Health (2016, November 01), 26(Suppl 1), 165021

Report on the Oberwolfach Workshop "Computations in the Cohomology of Arithmetic Groups"

in Oberwolfach Reports (2016, November)

Explicit calculations play an important role in the theoretical development of the cohomology of groups and its applications. It is becoming more common for such calculations to be derived with the aid of ... [more ▼]

Explicit calculations play an important role in the theoretical development of the cohomology of groups and its applications. It is becoming more common for such calculations to be derived with the aid of a computer. This mini-workshop assembled together experts on a diverse range of computational techniques relevant to calculations in the cohomology of arithmetic groups and applications in algebraic K-theory and number theory with a view to extending the scope of computer aided calculations in this area. [less ▲]

UAV degradation identification for pilot notification using machine learning techniques

in Proceedings of 21st IEEE International Conference on Emerging Technologies and Factory Automation ETFA 2016 (2016, September 06)

Unmanned Aerial Vehicles are currently investigated as an important sub-domain of robotics, a fast growing and truly multidisciplinary research field. UAVs are increasingly deployed in real-world settings ... [more ▼]

Unmanned Aerial Vehicles are currently investigated as an important sub-domain of robotics, a fast growing and truly multidisciplinary research field. UAVs are increasingly deployed in real-world settings for missions in dangerous environments or in environments which are challenging to access. Combined with autonomous flying capabilities, many new possibilities, but also challenges, open up. To overcome the challenge of early identification of degradation, machine learning based on flight features is a promising direction. Existing approaches build classifiers that consider their features to be correlated. This prevents a fine-grained detection of degradation for the different hardware components. This work presents an approach where the data is considered uncorrelated and, using machine learning <br />techniques, allows the precise identification of UAV’s damages. [less ▲]

Crystallographic and optoelectronic properties of the novel thin film absorber Cu2GeS3

in Proceedings of SPIE (2016, September)

Umsetzung der Inklusion in der Bildungslandschaft der EU: Anregungen für die Schweiz

in FACHFORUM SUPPORTED EDUCATION (2016, May 29)

Transmission polarized optical microscopy of short-pitch cholesteric liquid crystal shells

in Proceedings of SPIE - The International Society for Optical Engineering (2016, March 07), 9769

We recently demonstrated that colloidal crystal arrangements of monodisperse droplets or shells of planar-aligned cholesteric liquid crystal exhibit intricate patterns of circularly polarized reflection ... [more ▼]

We recently demonstrated that colloidal crystal arrangements of monodisperse droplets or shells of planar-aligned cholesteric liquid crystal exhibit intricate patterns of circularly polarized reflection spots of different colors. The spots appear as a result of photonic cross communication between droplets, hence the patterns reflect the macroscopic arrangement of droplets or shells. Apart from being an interesting optical phenomenon, it offers attractive application opportunities in photonics and beyond, due to the unique characteristics of the patterns. It turns out that the optical quality of shells is much enhanced compared to that of droplets, hence we focus our attention primarily on shells, of varying thickness. Here we analyze and explain the intriguing textures arising when studying planar-aligned short-pitch cholesteric shells in transmission polarizing optical microscopy. In this case, the texture reflects the properties of each individual shell, without any sign of cross communication, yet also this pattern holds some fascinating mysteries. These can only be elucidated by considering all the peculiar optical properties of cholesterics together, as well as the unusual situation given by the spherical shell geometry. [less ▲]

Fostering Reflective Thinking About Information In 5th Graders With Blogs: How Helpful Are Learning Supports?

in EAPRIL Conference Proceedings (2016, March), (2), 246-257

This study is about fostering media and information literacy and, more precisely, reflective thinking about information in 5th graders. A learning scenario integrating weblogs into a class by providing ... [more ▼]

This study is about fostering media and information literacy and, more precisely, reflective thinking about information in 5th graders. A learning scenario integrating weblogs into a class by providing learning tasks, learning supports and learning resources was elaborated and tested. The class was divided into a test group and a control group, which did not receive learning supports. Over five weeks the pupils ́ degree of reflection was measured by analysing their blog entries by means of pre- defined evaluation criteria. We also observed them while blogging and recorded our impressions. The results showed that, against our expectation, the pupils of the test group were less reflexive in their entries than the ones of the control group. However, we observed that the test group pupils verbally expressed many reflections, which they did not write down. This suggests that our learning scenario comprised of learning tasks, resources and supports promoted reflective thinking about information of all the pupils even if this is not recognisable in their entries. [less ▲]

ATTENTIONAL BIASES IN PAIN: A META-ANALYSIS OF DOT PROBE RESEARCH

in INTERNATIONAL JOURNAL OF BEHAVIORAL MEDICINE (2016), 23(1), 119

SimCoTest: A Test Suite Generation Tool for Simulink/Stateflow Controllers

in Proceedings of the 38th International Conference on Software Engineering (2016)

Stationary Wavelet Transform denoising in Pulsed Thermography: influence of camera resolution on defect detection

in Proceedings of 13th Conference on Advanced Infrared Technology and Applications (2016)

Denoising filters are widely used in image enhancement. However, they might induce severe blurring effects the lower is the resolution of the original image. When applied to a thermal image in Non ... [more ▼]

Denoising filters are widely used in image enhancement. However, they might induce severe blurring effects the lower is the resolution of the original image. When applied to a thermal image in Non-Destructive Testing (NDT), blurring could entail wrong estimation of defect boundaries and an overall reduction in defect detection performances. This contribution discusses the application of a wavelet-based denoising technique to a thermographic sequence obtained from a Pulsed Thermography testing, when using a high- resolution 1024x768 FPA infrared camera. Influence of denoising approach on data post- processed by Principal Component Analysis is discussed. Results indicate marked enhancement in defect detection, especially when compared to those obtained with a standard-resolution 320x240 FPA infrared camera. [less ▲]

Cohort factors impinging on suicide rates in the United States, 1990-2010

in PAA server (2016)

We use CDC microdata on cause of death and CPS data on populations by age to create suicide rates for five-year age groups at five-year intervals, further cross-classified by race/ethnicity, education ... [more ▼]

We use CDC microdata on cause of death and CPS data on populations by age to create suicide rates for five-year age groups at five-year intervals, further cross-classified by race/ethnicity, education, and marital status. We examine the suicide history 1990-2010 of U.S. birth cohorts, net of age and cohort linear trends. These de-trended cohort deviations follow familiar patterns: most pronounced in the Baby Boom, least pronounced during the Baby Bust, they illustrate the so-called Easterlin effect. Suicide rates for women show similar patterns as suicide patterns for men. We show persistence of those effects net of micro factors (especially education and marriage) implicated in suicide behavior and correlated at the macro level with relative cohort size. Analysis of suicide patterns over time for high- and low-educated men and women shows that white men with low education face a sharp increase, significantly above the linear time trends, in suicide rates among cohorts born between 1955 and 1970. This bump is mostly unrelated to secular trends of increasing average educational attainment rates, at least if no interaction between age and cohort is involved in the explanation. No obvious pattern related to cohort size is found for African-American high- and low-educated men, which makes sense given the very different historical dynamics for this minority sub-population. [less ▲]

Environmental stability of highly conductive nominally undoped ZnO layers

in IEEE Photovoltaic Specialists Conference. Conference Record (2016), 978-1-5090-2724

IMPLICIT AND EXPLICIT AGE STEREOTYPES FOR SPECIFIC LIFE DOMAINS ACROSS THE LIFE SPAN

in GERONTOLOGIST (2016), 56(3), 313-313

Inequality in old age cognition across the world

in PAA Server (2016)

Textual Inference with Deep Learning Technique

in Proceedings of the 28th Annual Benelux Conference on Artificial Intelligence (BNAIC2016). (2016)

Exploring therapeutic viability of a non-dopaminergic target for Parkinson’s disease

in Movement Disorders (2016), 31(2), 630

Entwicklung eines PVT-basierten Wärmepumpensystems auf der Basis von CO2 Direktverdampfung

in Proceedings of Deutsche Kälte- und Klimatagung (DKV) (2016)

Bereits Ende der 1970’iger Jahren wurden Wärmepumpen in Kombination mit glykolbasierten großflächigen Absorbern entwickelt, welche sich die Umgebungsenergie und Solarenergie als Energiequelle zu Nutze ... [more ▼]

Bereits Ende der 1970’iger Jahren wurden Wärmepumpen in Kombination mit glykolbasierten großflächigen Absorbern entwickelt, welche sich die Umgebungsenergie und Solarenergie als Energiequelle zu Nutze machen. Aufgrund der nach der Ölkrise fallenden Ölpreise, der meist noch nicht wirtschaftlichen Anlagentechnik und den benötigten großen Absorberflächen, konnten sich diese Anlagen nicht durchsetzen. Durch die starke Reduzierung des Heizwärmebedarfs eines heutigen Neubaus werden heutzutage deutlich kleinere Absorberflächen in Kombination mit einer Wärmepumpe benötigt, was die Systemkombination aus Wärmepumpe und Absorber aktuell wieder interessant werden lässt. Vor allem die Kombination aus thermischen Absorber, basierend auf freier Konvektion und Strahlung, und Photovoltaik (PV) in einem Modul (PVT-Modul) kann aufgrund der Reduzierung des Heizwärmebedarfs von Gebäuden und des verstärkten Betriebs von Wärmepumpen während der Niedrigstrompreiszeiten am Tage und dem damit verbundenen höheren Strahlungsanteil der Umweltwärme zukünftig eine Alternative zu zwangskonvektions-basierten Luft-Wärmepumpen sein. Im Rahmen dieser Arbeit wird auf die Konstruktion eines funktionsfähigen PVT-direkt Moduls eingegangen, welches einen mikrokanalbasierten Verdampfer einer transkritischen CO2-Wärmepumpe mit einem PV-Modul kombiniert. Im ersten Teil dieser Arbeit wird ein thermisches Modell des PVT-direkt Moduls hergeleitet, welches in zukünftigen Untersuchungen Anwendung findet, um eine Aussage über die PV-seitige Wirkungsgradsteigerung durch niedrigere Modultemperaturen aufgrund der Kältemittelverdampfung an der Modulrückseite treffen zu können. Der zweite Teil dieser Arbeit präsentiert die Auslegung zweier Verdampfer-Designvarianten (Mäander und Harfendesign) und eine Temperaturverteilungsanalyse. Bei beiden Konzepten fällt die Temperaturverteilung annähernd homogen aus. [less ▲]