References of "Engel, Thomas 50001752"
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See detailImproving Traffic in Urban Environments
Codeca, Lara UL; Frank, Raphaël UL; Engel, Thomas UL

Report (2014)

The vehicular traffic in the cities is increasing every year. The road infrastructure in many metropolitan areas is not able to sustain the rush-hour traffic demand and the extension of the road network ... [more ▼]

The vehicular traffic in the cities is increasing every year. The road infrastructure in many metropolitan areas is not able to sustain the rush-hour traffic demand and the extension of the road network cannot easily be done. There are some solution proposed to improve the traffic situation, among them, the optimization of the resources already available by means of collecting real time Floating Car Data (FCD) from the vehicles and use them to suggest dynamic routes in order to minimize travel delays. The centralized infrastructure able to achieve this goal has already been presented in ”Improving Traffic in Urban Environments applying the Wardrop Equilibrium” (Codeca, L. et al., 2013). In this extended abstract we present the decentralized version of the system and the preliminary results of its evaluation. [less ▲]

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See detailCollaborative Traffic Sensing: A Case Study of a Mobile Phone Based Traffic Management System
Frank, Raphaël UL; Weitz, Hervé UL; Castignani, German UL et al

in Proceedings of the 11th IEEE Consumer Communications and Networking Conference (CCNC'14) (2014, January 10)

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See detailDevice-Free Indoor Localization Based on Ambient FM Radio Signals
Popleteev, Andrei UL; Engel, Thomas UL

in International Journal of Ambient Computing and Intelligence (2014), 6(January-March), 35-44

This paper presents the concept of device-free indoor localization using only a passive receiver and ambient FM radio signals. Experimental results based on empirical measurements demonstrate the ... [more ▼]

This paper presents the concept of device-free indoor localization using only a passive receiver and ambient FM radio signals. Experimental results based on empirical measurements demonstrate the feasibility of the proposed approach. We also evaluate fine-grained localization performance of the system, its temporal stability, and highlight the role of frequency diversity for passive localization. [less ▲]

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See detailA Cooperative Advanced Driver Assistance System to Mitigate Vehicular Traffic Shock Waves
Forster, Markus UL; Frank, Raphaël UL; Gerla, Mario et al

in IEEE INFOCOM 2014 - IEEE Conference on Computer Communications (2014)

We address the problem of shock wave formation in uncoordinated highway traffic. First, we identify the combination of heavy traffic and small traffic perturbations or unexpected driver actions as the ... [more ▼]

We address the problem of shock wave formation in uncoordinated highway traffic. First, we identify the combination of heavy traffic and small traffic perturbations or unexpected driver actions as the main causes of highway traffic jams. Then we introduce a novel distributed communication protocol that enables us to eliminate upstream shock wave formation even with low system penetration rates. Based on traffic information ahead, we propose a Cooperative Advanced Driver Assistance System (CADAS) that recommends non-intuitive velocity reductions in order to redistribute traffic more uniformly thereby eliminating traffic peaks. Simulation results show that CADAS significantly increases the average velocity and therewith reduces the overall travel time and avoids unnecessary slowdowns. [less ▲]

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See detailTowards Domain Completeness for Model Transformations Based on Triple Graph Grammars
Nachtigall, Nico UL; Hermann, Frank UL; Braatz, Benjamin UL et al

in Amrani, Moussa; Syriani, Eugene; Wimmer, Manuel (Eds.) Proceedings of the Third International Workshop on Verification of Model Transformations - co-located with Software Technologies: Applications and Foundations (STAF 2014) (2014)

The analysis of model transformations is a challenging research area within model driven engineering. Triple graph grammars (TGGs) have been applied in various transformation scenarios and their formal ... [more ▼]

The analysis of model transformations is a challenging research area within model driven engineering. Triple graph grammars (TGGs) have been applied in various transformation scenarios and their formal foundation has been a vital ground for general results concerning notions of correctness and completeness. This paper addresses existing gaps between practical scenarios and the formal results of TGGs concerning the notion of completeness. Since the source domain language of a model transformation is usually specified independently from the TGG, we use the notion of domain completeness, which requires that the model transformation has to provide a corresponding target model for each model of the source domain language. As main result, we provide a general method for showing that the source domain language is included in the language that is generated by the source rules of the TGG. This provides the first of two components for verifying domain completeness. The running example is the well studied object-relational mapping. [less ▲]

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See detailCognition: a tool for reinforcing security in Software Defined Netwks
Tantar, Emilia UL; Palattella, Maria Rita UL; Avanesov, Tigran UL et al

in Tantar, Alexandru-Adrian; Tantar, Emilia; Jian-Qiao, Sun (Eds.) et al EVOLVE - A Bridge between Probability, Set Oriented Numerics, and Evolutionary Computation V (2014)

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See detailLetting the Puss in Boots Sweat: Detecting Fake Access Points using Dependency of Clock Skews on Temperature
Lanze, Fabian UL; Panchenko, Andriy UL; Braatz, Benjamin UL et al

in Proceedings of the 9th ACM Symposium on Information, Computer and Communications Security (ASIACCS 2014) (2014)

Detailed reference viewed: 238 (17 UL)
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See detail6TiSCH Wireless Industrial Networks: Determinism meet IPv6
Palattella, Maria Rita UL; Thubert, Pascal; Vilajosana, Xavier et al

in Internet of Things: Challenges and Opportunities. Lecture series of Smart Sensors, Measurements, and Instrumentation. vol 9 (2014)

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See detailSolving the FIXML2Code-case Study with HenshinTGG
Hermann, Frank UL; Nachtigall, Nico UL; Braatz, Benjamin UL et al

in Rose, Louis M.; Krause, Christian; Horn, Tassilo (Eds.) Proceedings of the 7th Transformation Tool Contest - part of the Software Technologies: Applications and Foundations (STAF 2014) federation of conferences (2014)

Triple graph grammars (TGGs) provide a formal framework for bidirectional model transformations. As in practice, TGGs are primarily used in pure model-to-model transformation scenarios, tools for text-to ... [more ▼]

Triple graph grammars (TGGs) provide a formal framework for bidirectional model transformations. As in practice, TGGs are primarily used in pure model-to-model transformation scenarios, tools for text-to-model and model-to-text transformations make them also applicable in text-to-text transformation contexts. This paper presents a solution for the text-to-text transformation case study of the Transformation Tool Contest 2014 on translating FIXML (an XML notation for financial transactions) to source code written in Java, C# or C++. The solution uses the HenshinTGG tool for specifying and executing model-to-model transformations based on the formal concept of TGGs as well as the Xtext tool for parsing XML content to yield its abstract syntax tree (text-to-model transformation) and serialising abstract syntax trees to source code (model-to-text transformation). The approach is evaluated concerning a given set of criteria. [less ▲]

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See detailImplications and Detection of DoS Attacks in OpenFlow-based Networks
Hommes, Stefan UL; State, Radu UL; Engel, Thomas UL

in 2014 IEEE Global Communications Conference (2014)

In this paper, we address the potential of centralised network monitoring based on Software-Defined Networking with OpenFlow. Due to the vulnerability of the flow table, which can store only a limited ... [more ▼]

In this paper, we address the potential of centralised network monitoring based on Software-Defined Networking with OpenFlow. Due to the vulnerability of the flow table, which can store only a limited number of entries, we discuss and show the implications for a DoS attack on a testbed consisting of OpenFlow enabled network devices. Such an attack can be detected by analysing variations in the logical topology, using techniques from information theory that can run as a network service on the network controller. [less ▲]

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See detailA Study of Urban IEEE 802.11 Hotspot Networks: Towards a Community Access Network
Castignani, German UL; Monetti, Juan; Montavont, Nicolas et al

in A Study of Urban IEEE 802.11 Hotspot Networks: Towards a Community Access Network (2013, November 13)

With the increasing demand for faster data connectivity, different wireless technologies have been deployed in the last decade, creating a heterogeneous wireless environment. Such wireless diversity is ... [more ▼]

With the increasing demand for faster data connectivity, different wireless technologies have been deployed in the last decade, creating a heterogeneous wireless environment. Such wireless diversity is mainly composed of 2G/3G/4G cellular base stations, IEEE 802.11 hotspots and Community Networks. Previous work suggests that the increasing popularity of IEEE 802.11 networks would mitigate the overloading of current operator-based cellular deployments. However, the unpredictable characteristics of IEEE 802.11 deployments and its loose coupling to cellular architectures limit its user performance in terms of throughput and mobility capacity. In this paper, we describe an evaluation study of a commercial-grade hotspot network in the city of Luxembourg, namely HOTCITY. Through a set of experiments, we provide a characterization of the hotspot network and give a set of performance indicators. Finally, we evaluate hotspot networks' potential to support cellular offloading through the integration of outdoor hotspots and private access points deployed indoors in a single Community Network. [less ▲]

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See detailImproving Traffic in Urban Environments applying the Wardrop Equilibrium
Codeca, Lara UL; Frank, Raphaël UL; Engel, Thomas UL

in Improving Traffic in Urban Environments applying the Wardrop Equilibrium (2013, October 07)

Over the last few years vehicular traffic density has continuously increased and it is likely that the traffic demand will further increase in the future. In many metropolitan areas the road ... [more ▼]

Over the last few years vehicular traffic density has continuously increased and it is likely that the traffic demand will further increase in the future. In many metropolitan areas the road infrastructure is no longer able to handle the peak traffic demand and the existing road network cannot be easily extended. The best way to improve the traffic situation is to optimise the resources available in the transportation network and to coordinate the traffic demand. The approach that we propose in this paper makes use of a collaborative traffic coordination protocol which collects real-time Floating Car Data (FCD) directly from participating vehicles and suggests dynamic routes in order to minimize travel delay. Information such as speed, position and direction is sent to one or more Traffic Coordination Points (TCPs) where it is aggregated to obtain a global picture of the traffic conditions in real-time. Based on this data, we continuously compute the route that minimizes the travel time to a given destination by applying Wardrop’s first principle of equilibrium. Our results show that, by coordinating the vehicles, we are able to better distribute the overall traffic demand throughout the transportation network, reducing the average travel times and accommodating more vehicles. [less ▲]

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See detailIdentifying abnormal pattern in cellular communication flows
Goergen, David UL; Mendiratta, Veena; State, Radu UL et al

in Proceedings of IPTComm 2013 (2013, October)

Analyzing communication flows on the network can help to improve the overall quality it provides to its users and allow the operators to detect abnormal patterns and react accordingly. In this paper we ... [more ▼]

Analyzing communication flows on the network can help to improve the overall quality it provides to its users and allow the operators to detect abnormal patterns and react accordingly. In this paper we consider the analysis of large volumes of cellular communications records. We propose a method that detects abnormal communications events covering call data record volumes, comprising a country-level data set. We detect patterns by calculating a weighted average using a sliding window with a fixed period and correlate the results with actual events happening at that time. We are able to successfully detect several events using a data set provided by a mobile phone operator, and suggest examples of future usage of the outcome such as real time pattern detection and possible visualisation for mobile phone operators. [less ▲]

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See detailDriver diaries: a multimodal mobility behaviour logging methodology
Kracheel, Martin UL; McCall, Roderick UL; Koenig, Vincent UL et al

in Proceedings of the 5th International Conference on Automotive User Interfaces and Interactive Vehicular Applications (2013, October)

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See detailClassification of Log Files with Limited Labeled Data
Hommes, Stefan UL; State, Radu UL; Engel, Thomas UL

in Proceedings of IPTComm 2013 (2013, October)

We address the problem of anomaly detection in log files that consist of a huge number of records. In order to achieve this task, we demonstrate label propagation as a semi-supervised learning technique ... [more ▼]

We address the problem of anomaly detection in log files that consist of a huge number of records. In order to achieve this task, we demonstrate label propagation as a semi-supervised learning technique. The strength of this approach lies in the small amount of labelled data that is needed to label the remaining data. This is an advantage since labelled data needs human expertise which comes at a high cost and be- comes infeasible for big datasets. Even though our approach is generally applicable, we focus on the detection of anoma- lous records in firewall log files. This requires a separation of records into windows which are compared using different distance functions to determine their similarity. Afterwards, we apply label propagation to label a complete dataset in only a limited number of iterations. We demonstrate our approach on a realistic dataset from an ISP. [less ▲]

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See detailAutomated Source Code Extension for Debugging of OpenFlow based Networks
Hommes, Stefan UL; Hermann, Frank UL; State, Radu UL et al

in Proc. 9th International Conference on Network and Service Management (CNSM) (2013, October)

Software-Defined Networks using OpenFlow have to provide a reliable way to to detect network faults in operational environments. Since the functionality of such networks is mainly based on the installed ... [more ▼]

Software-Defined Networks using OpenFlow have to provide a reliable way to to detect network faults in operational environments. Since the functionality of such networks is mainly based on the installed software, tools are required in order to determine software bugs. Moreover, network debugging might be necessary in order to detect faults that occurred on the network devices. To determine such activities, existing controller programs must be extended with the relevant functionality. In this paper we propose a framework that can modify controller programs transparently by using graph transformation, making possible online fault management through logging of network parameters in a NoSQL database. Latter acts as a storage system for flow entries and respective parameters, that can be leveraged to detect network anomalies or to perform forensic analysis. [less ▲]

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See detailDriver Behavior Profiling using Smartphones
Castignani, German UL; Frank, Raphaël UL; Engel, Thomas UL

in Driver Behavior Profiling using Smartphones (2013, October)

The proliferation of smartphones and mobile devices embedding different types of sensors sets up a prodigious and distributed sensing platform. In particular, in the last years there has been an ... [more ▼]

The proliferation of smartphones and mobile devices embedding different types of sensors sets up a prodigious and distributed sensing platform. In particular, in the last years there has been an increasing necessity to monitor drivers to identify bad driving habits in order to optimize fuel consumption, to reduce CO2 emissions or, indeed, to design new reliable and fair pricing schemes for the insurance market. In this paper, we analyze the driver sensing capacity of smartphones. We propose a mobile tool that makes use of the most common sensors embedded in current smartphones and implement a Fuzzy Inference System that scores the overall driving behavior by combining different fuzzy sensing data. [less ▲]

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See detailAn Evaluation Study of Driver Profiling Fuzzy Algorithms using Smartphones
Castignani, German UL; Frank, Raphaël UL; Engel, Thomas UL

in An Evaluation Study of Driver Profiling Fuzzy Algorithms using Smartphones (2013, October)

Profiling driving behavior has become a relevant aspect in fleet management, automotive insurance and eco-driving. Detecting inefficient or aggressive drivers can help reducing fleet degradation ... [more ▼]

Profiling driving behavior has become a relevant aspect in fleet management, automotive insurance and eco-driving. Detecting inefficient or aggressive drivers can help reducing fleet degradation, insurance policy cost and fuel consumption. In this paper, we present a Fuzzy-Logic based driver scoring mechanism that uses smartphone sensing data, including accelerometers and GPS. In order to evaluate the proposed mechanism, we have collected traces from a testbed consisting in 20 vehicles equipped with an Android sensing application we have developed to this end. The results show that the proposed sensing variables using smartphones can be merged to provide each driver with a single score. [less ▲]

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See detailAdvanced Detection Tool for PDF Threats
Jerome, Quentin UL; Marchal, Samuel UL; State, Radu UL et al

in Proceedings of the sixth International Workshop on Autonomous and Spontaneous Security, RHUL, Egham, U.K., 12th-13th September 2013 (2013, September 13)

In this paper we introduce an efficient application for malicious PDF detection: ADEPT. With targeted attacks rising over the recent past, exploring a new detection and mitigation paradigm becomes ... [more ▼]

In this paper we introduce an efficient application for malicious PDF detection: ADEPT. With targeted attacks rising over the recent past, exploring a new detection and mitigation paradigm becomes mandatory. The use of malicious PDF files that exploit vulnerabilities in well-known PDF readers has become a popular vector for targeted at- tacks, for which few efficient approaches exist. Although simple in theory, parsing followed by analysis of such files is resource-intensive and may even be impossible due to several obfuscation and reader-specific artifacts. Our paper describes a new approach for detecting such malicious payloads that leverages machine learning techniques and an efficient feature selection mechanism for rapidly detecting anomalies. We assess our approach on a large selection of malicious files and report the experimental performance results for the developed prototype. [less ▲]

Detailed reference viewed: 873 (6 UL)