Dr. Marco Maier

Dr. Marco Maier

Lehrstuhl für Mobile und Verteilte Systeme

Ludwig-Maximilians-Universität München, Institut für Informatik

Oettingenstraße 67
80538 München

Raum U 169

Telefon: +49 89 / 2180-9664

Fax: +49 89 / 2180-9148

Mail: marco.maier@ifi.lmu.de

Aufgabengebiet

(Collaborative) Context Recognition
Mobile and P2P Online Social Networks
Privacy and Security In Context Aware Systems

Abschlussarbeiten

Bei Interesse an einer Abschlussarbeit in meinen Themengebieten, gerne einfach eine E-Mail schicken und zu einem Gespräch vorbeikommen. Eigene Ideen für Abschlussarbeiten sind auch jederzeit willkommen.

Publikationen

2016

  • C. Marouane, M. Maier, A. Leupold, and C. Linnhoff-Popien, „Visual Odometry using motion vectors from visual feature points,“ in 7th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2016), 2016, pp. 1-8.
    [BibTeX]
    @inproceedings{marouane2016kompass,
    title = {Visual Odometry using motion vectors from visual feature points},
    author = {Chadly Marouane and Marco Maier and Alexander Leupold and Claudia Linnhoff-Popien},
    booktitle = {7th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2016)},
    year = {2016},
    pages = {1-8},
    owner = {cmarouane},
    timestamp = {2016.11.25}
    }

2015

  • F. Dorfmeister, K. Wiesner, M. Schuster, and M. Maier, „Preventing Restricted Space Inference in Online Route Planning Services,“ in 12th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS 2015), 2015.
    [BibTeX]
    @inproceedings{dorfmeister2015prospr,
    title = {Preventing Restricted Space Inference in Online Route Planning Services},
    author = {Florian Dorfmeister and Kevin Wiesner and Michael Schuster and Marco Maier},
    booktitle = {12th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS 2015)},
    year = {2015},
    owner = {fdorfmeister},
    timestamp = {2015.07.10}
    }

  • A. Ebert, F. Dorfmeister, M. Maier, and C. Linnhoff-Popien, „Context-, Resource-, and User-Aware Provision of Services on Mobile Devices,“ International Journal On Advances in Networks and Services, vol. 8, iss. 1&2, pp. 81-91, 2015.
    [BibTeX]
    @article{crua15,
    title = {Context-, Resource-, and User-Aware Provision of Services on Mobile Devices},
    author = {André Ebert and Florian Dorfmeister and Marco Maier and Claudia Linnhoff-Popien},
    journal = {International Journal On Advances in Networks and Services},
    year = {2015},
    number = {1\&2},
    pages = {81 -91},
    volume = {8},
    owner = {aebert},
    timestamp = {2015.07.17}
    }

  • A. Ebert, F. Dorfmeister, M. Maier, and C. Linnhoff-Popien, „EMMA: A Context-Aware Middleware For Energy Management on Mobile Devices,“ in 7th International Conference on Advances in Human-oriented and Personalized Mechanisms, Technologies, and Services (SoftNet 2014), 2015.
    [BibTeX]
    @inproceedings{emma14,
    title = {EMMA: A Context-Aware Middleware For Energy Management on Mobile Devices},
    author = {André Ebert and Florian Dorfmeister and Marco Maier and Claudia Linnhoff-Popien},
    booktitle = {7th International Conference on Advances in Human-oriented and Personalized Mechanisms, Technologies, and Services (SoftNet 2014)},
    year = {2015},
    publisher = {IARIA},
    owner = {aebert},
    timestamp = {2015.07.17}
    }

  • M. Maier, L. Schauer, and F. Dorfmeister, „ProbeTags: Privacy-Preserving Proximity Detection Using Wi-Fi Management Frames,“ in 11th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WIMOB 2015), 2015.
    [BibTeX]
    @inproceedings{maier15probetags,
    title = {ProbeTags: Privacy-Preserving Proximity Detection Using Wi-Fi Management Frames},
    author = {Marco Maier and Lorenz Schauer and Florian Dorfmeister},
    booktitle = {11th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WIMOB 2015)},
    year = {2015},
    owner = {mmaier},
    timestamp = {2015.11.13}
    }

2014

  • M. T. Beck and M. Maier, „Mobile Edge Computing: Challenges for Future Virtual Network Embedding Algorithms,“ in 8th International Conference on Advanced Engineering Computing and Applications in Sciences (ADVCOMP 2014), 2014.
    [BibTeX]
    @inproceedings{mecvne,
    title = {Mobile Edge Computing: Challenges for Future Virtual Network Embedding Algorithms},
    author = {Michael Till Beck and Marco Maier},
    booktitle = {8th International Conference on Advanced Engineering Computing and Applications in Sciences (ADVCOMP 2014)},
    year = {2014},
    publisher = {AdvComp},
    keywords = {Virtual Network Embedding, Next-gen Cellular Networks, Edge Computing}
    }

  • M. Maier, C. Marouane, M. Klette, F. Dorfmeister, P. Marcus, and C. Linnhhoff-Popien, „SURFtogether: Towards Context Proximity Detection Using Visual Features,“ in 3rd International Conference on Context-Aware Systems and Applications (ICCASA 2014), 2014, pp. 86-91.
    [BibTeX]
    @inproceedings{maier2014surftogether,
    title = {SURFtogether: Towards Context Proximity Detection Using Visual Features},
    author = {Marco Maier and Chadly Marouane and Manuel Klette and Florian Dorfmeister and Philipp Marcus and Claudia Linnhhoff-Popien},
    booktitle = {3rd International Conference on Context-Aware Systems and Applications (ICCASA 2014)},
    year = {2014},
    pages = {86-91},
    owner = {mmaier},
    timestamp = {2015.07.10}
    }

  • M. Maier, C. Marouane, and C. Linnhoff-Popien, „Vis-a-Vis: Offline-Capable Management of Virtual Trust Structures Based on Real-Life Interactions,“ International Journal On Advances in Life Sciences, vol. 6, iss. 1 and 2, pp. 1-10, 2014.
    [BibTeX] [Abstract] [Download PDF]

    Online services, particularly those aimed at a specific user base such as a company’s employees, face the problem of identity management. Especially when the service constitutes some kind of social network, i.e., the validity of the users‘ identities matters, secure and reliable means for identity verification and authentication are required. In this paper, predicated on our previous work, we propose an identity management concept based on a) verification through physical presence and b) authentication through ownership. Our approach being a hybrid solution between a centralized authority and decentralized trust management is settled on a sweet spot between security and convenience for the users. In this extended version, we present the newly proposed Tree of Trust structure in more detail, and provide a thourough explanation how the system can be used in a technically more distributed manner, even supporting offline operation.

    @article{visavis2014,
    title = {Vis-a-Vis: Offline-Capable Management of Virtual Trust Structures Based on Real-Life Interactions},
    author = {Marco Maier and Chadly Marouane and Claudia Linnhoff-Popien},
    journal = {International Journal On Advances in Life Sciences},
    year = {2014},
    number = {1 and 2},
    pages = {1-10},
    volume = {6},
    abstract = {Online services, particularly those aimed at a specific user base such as a company's employees, face the problem of identity management. Especially when the service constitutes some kind of social network, i.e., the validity of the users' identities matters, secure and reliable means for identity verification and authentication are required. In this paper, predicated on our previous work, we propose an identity management concept based on a) verification through physical presence and b) authentication through ownership. Our approach being a hybrid solution between a centralized authority and decentralized trust management is settled on a sweet spot between security and convenience for the users. In this extended version, we present the newly proposed Tree of Trust structure in more detail, and provide a thourough explanation how the system can be used in a technically more distributed manner, even supporting offline operation.},
    owner = {mmaier},
    timestamp = {2014.09.04},
    url = {http://www.thinkmind.org/download.php?articleid=lifsci_v6_n12_2014_1}
    }

  • C. Marouane, M. Maier, S. Feld, and M. Werner, „Visual Positioning Systems – An Extension to MoVIPS,“ in 5th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2014), 2014, pp. 95-104.
    [BibTeX] [Abstract]

    Due to the increasing popularity of location-based services, the need for reliable and cost-effective indoor positioning methods is rising. As an alternative to radio-based localization methods, in 2011, we introduced MoVIPS (Mobile Visual Indoor Positioning System), which is based on the idea to extract visual feature points from a query image and compare them to those of previously collected geo-referenced images. The general feasibility of positioning by SURF points on a conventional smartphone was already shown in our previous work. However, the system still faced several shortcomings concerning real-world usage such as request times being too high and distance estimation being unreliable because of the employed estimation method not being rotation invariant. In this paper, three extensions are presented that improve the practical applicability of MoVIPS. To speed up request times, both a dead reckoning approach (based on step counting using the accelerometer) and an orientation estimation (based on the smartphone’s compass) are introduced to filter relevant images from the database and thus to reduce the amount of images to compare the query image to. Furthermore, the vectors of the SURF points are quantized. For this purpose, clusters are calculated from all SURF points from the database. As a result, each image can be represented by a histogram of cluster frequencies, which can be compared with each other a lot more efficiently. The third extension is an improvement of the distance estimation method, which uses the matched feature points of an image to perform a perspective transformation and to determine the actual position with the aid of the transformation matrix. Employing the first extension, request times are reduced by 84\% percent. The quantization of the SURF points reduces the search time by a factor of 1000. Finally, the distance estimation is now rotation invariant and enables a better position correction.

    @inproceedings{marouane2014visual,
    title = {Visual Positioning Systems - An Extension to MoVIPS},
    author = {Chadly Marouane and Marco Maier and Sebastian Feld and Martin Werner},
    booktitle = {5th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2014)},
    year = {2014},
    pages = {95-104},
    abstract = {Due to the increasing popularity of location-based services, the need for reliable and cost-effective indoor positioning methods is rising. As an alternative to radio-based localization methods, in 2011, we introduced MoVIPS (Mobile Visual Indoor Positioning System), which is based on the idea to extract visual feature points from a query image and compare them to those of previously collected geo-referenced images. The general feasibility of positioning by SURF points on a conventional smartphone was already shown in our previous work. However, the system still faced several shortcomings concerning real-world usage such as request times being too high and distance estimation being unreliable because of the employed estimation method not being rotation invariant. In this paper, three extensions are presented that improve the practical applicability of MoVIPS. To speed up request times, both a dead reckoning approach (based on step counting using the accelerometer) and an orientation estimation (based on the smartphone's compass) are introduced to filter relevant images from the database and thus to reduce the amount of images to compare the query image to. Furthermore, the vectors of the SURF points are quantized. For this purpose, clusters are calculated from all SURF points from the database. As a result, each image can be represented by a histogram of cluster frequencies, which can be compared with each other a lot more efficiently. The third extension is an improvement of the distance estimation method, which uses the matched feature points of an image to perform a perspective transformation and to determine the actual position with the aid of the transformation matrix. Employing the first extension, request times are reduced by 84\% percent. The quantization of the SURF points reduces the search time by a factor of 1000. Finally, the distance estimation is now rotation invariant and enables a better position correction.},
    owner = {cmarouane}
    }

2013

  • M. Maier and F. Dorfmeister, „Fine-Grained Activity Recognition of Pedestrians Travelling by Subway,“ in 5th International Conference on Mobile Computing, Applications and Services (MobiCASE 2013), 2013. doi:10.1007/978-3-319-05452-0_10
    [BibTeX] [Abstract] [Download PDF]

    With the now widespread usage of increasingly powerful smartphones, pro-active, context-aware, and thereby unobstrusive applications have become possible. A user’s current activity is a primary piece of contextual information, and especially in urban areas, a user’s current mode of transport is an important part of her activity. A lot of research has been conducted on automatically recognizing different means of transport, but up to now, no attempt has been made to perform a fine-grained classification of different activities related to travelling by local public transport. In this work, we present an approach to recognize 17 different activities related to travelling by subway. We use only the sensor technology available in modern mobile phones and achieve a high classification accuracy of over 90%, without requiring a specific carrying position of the device. We discuss the usefulness of different sensors and computed features, and identify individual characteristics of the considered activities.

    @inproceedings{subway,
    title = {Fine-Grained Activity Recognition of Pedestrians Travelling by Subway},
    author = {Marco Maier and Florian Dorfmeister},
    booktitle = {5th International Conference on Mobile Computing, Applications and Services (MobiCASE 2013)},
    year = {2013},
    abstract = {With the now widespread usage of increasingly powerful smartphones, pro-active, context-aware, and thereby unobstrusive applications have become possible. A user’s current activity is a primary piece of contextual information, and especially in urban areas, a user’s current mode of transport is an important part of her activity. A lot of research has been conducted on automatically recognizing different means of transport, but up to now, no attempt has been made to perform a fine-grained classification of different activities related to travelling by local public transport. In this work, we present an approach to recognize 17 different activities related to travelling by subway. We use only the sensor technology available in modern mobile phones and achieve a high classification accuracy of over 90%, without requiring a specific carrying position of the device. We discuss the usefulness of different sensors and computed features, and identify individual characteristics of the considered activities.},
    doi = {10.1007/978-3-319-05452-0_10},
    url = {http://link.springer.com/chapter/10.1007/978-3-319-05452-0_10}
    }

  • M. Maier, C. Marouane, C. Linnhoff-Popien, B. Rott, and S. A. W. Verclas, „Vis-a-Vis Verification: Social Network Identity Management Through Real World Interactions,“ in 3rd International Conference on Social Eco-Informatics (SOTICS 2013), 2013, pp. 39-44.
    [BibTeX] [Abstract] [Download PDF]

    Online services, particularly those aimed at a specific user base such as a company’s employees, face the problem of identity management. Especially when the service constitutes some kind of social network, i.e., the validity of the users‘ identities matters, secure and reliable means for identity verification and authentication are required. In this paper, we propose a novel identity management concept based on a) verification through physical presence and b) authentication through ownership. Our approach being a hybrid solution between a centralized authority and decentralized trust management is settled on a sweet spot between security and convenience for the users.

    @inproceedings{visavis,
    title = {Vis-a-Vis Verification: Social Network Identity Management Through Real World Interactions},
    author = {Marco Maier and Chadly Marouane and Claudia Linnhoff-Popien and Benno Rott and Stephan A. W. Verclas},
    booktitle = {3rd International Conference on Social Eco-Informatics (SOTICS 2013)},
    year = {2013},
    pages = {39-44},
    abstract = {Online services, particularly those aimed at a specific user base such as a company's employees, face the problem of identity management. Especially when the service constitutes some kind of social network, i.e., the validity of the users' identities matters, secure and reliable means for identity verification and authentication are required. In this paper, we propose a novel identity management concept based on a) verification through physical presence and b) authentication through ownership. Our approach being a hybrid solution between a centralized authority and decentralized trust management is settled on a sweet spot between security and convenience for the users.},
    keywords = {identity management systems; authentication; social network services; mobile computing},
    url = {http://www.thinkmind.org/download.php?articleid=sotics_2013_3_10_30054}
    }

  • L. Schauer, F. Dorfmeister, and M. Maier, „Potentials and Limitations of WIFI-Positioning Using Time-of-Flight,“ in 4th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2013), 2013, pp. 1-9.
    [BibTeX] [Download PDF]
    @inproceedings{tof,
    title = {Potentials and Limitations of WIFI-Positioning Using Time-of-Flight},
    author = {Lorenz Schauer and Florian Dorfmeister and Marco Maier},
    booktitle = {4th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2013)},
    year = {2013},
    pages = {1-9},
    url = {http://www.cip.ifi.lmu.de/~schauer/publications/WifiTOF.pdf}
    }

2012

  • F. Dorfmeister, M. Maier, M. Schönfeld, and S. A. W. Verclas, „SmartBEEs: Enabling Smart Business Environments Based on Location Information and Sensor Networks,“ in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 43-56.
    [BibTeX]
    @inproceedings{smartbeees,
    title = {SmartBEEs: Enabling Smart Business Environments Based on Location Information and Sensor Networks},
    author = {Florian Dorfmeister and Marco Maier and Mirco Schönfeld and Stephan A. W. Verclas},
    booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    year = {2012},
    pages = {43-56}
    }

  • M. Dürr, M. Maier, and F. Dorfmeister, „Vegas – A Secure and Privacy-Preserving Peer-to-Peer Online Social Network,“ in IEEE/ASE Workshop on Security and Privacy of Social Networks (SPSN 2012), in conjunction with The Fourth IEEE/ASE International Conference on Social Computing (SocialCom 2012), 2012, pp. 868-874. doi:10.1109/SocialCom-PASSAT.2012.42
    [BibTeX]
    @inproceedings{vegas,
    title = {Vegas - A Secure and Privacy-Preserving Peer-to-Peer Online Social Network},
    author = {Michael Dürr and Marco Maier and Florian Dorfmeister},
    booktitle = {IEEE/ASE Workshop on Security and Privacy of Social Networks (SPSN 2012), in conjunction with The Fourth IEEE/ASE International Conference on Social Computing (SocialCom 2012)},
    year = {2012},
    pages = {868-874},
    doi = {10.1109/SocialCom-PASSAT.2012.42}
    }

  • M. Dürr, M. Maier, and K. Wiesner, „An Analysis of Query Forwarding Strategies for Secure and Privacy-Preserving Social Networks,“ in IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining (ASONAM 2012), 2012, pp. 535-542.
    [BibTeX] [Download PDF]
    @inproceedings{vegasqueries,
    title = {An Analysis of Query Forwarding Strategies for Secure and Privacy-Preserving Social Networks},
    author = {Michael Dürr and Marco Maier and Kevin Wiesner},
    booktitle = {IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining (ASONAM 2012)},
    year = {2012},
    pages = {535-542},
    publisher = {IEEE},
    isbn = {978-0-7695-4799-2},
    numpages = {8},
    url = {http://dx.doi.org/10.1109/ASONAM.2012.92}
    }

  • M. Kessel, M. Maier, M. Schönfeld, and F. Dorfmeister, „Testing Sensor Fusion Algorithms in Indoor Positioning Scenarios,“ in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 133-142.
    [BibTeX] [Abstract]

    Location information is the foundation for location based services. However, a cheap and global indoor positioning solution offering a sufficiently high accuracy and precision for most applications is not yet available and detains location based services from indoor areas. This is also due to missing comparability and standards in the field of indoor positioning, resulting in a large number of proprietary research prototypes of varying capabilities. In this paper we present a software environment for testing and comparing sensor fusion algorithms in indoor positioning scenarios. For this purpose an extendable tool for evaluating accuracy, precision, robustness, complexity, and storage is designed and the results from a first implementation presented and discussed.

    @inproceedings{sensorfusiontool,
    title = {Testing Sensor Fusion Algorithms in Indoor Positioning Scenarios},
    author = {Moritz Kessel and Marco Maier and Mirco Schönfeld and Florian Dorfmeister},
    booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    year = {2012},
    pages = {133-142},
    abstract = {Location information is the foundation for location based services. However, a cheap and global indoor positioning solution offering a sufficiently high accuracy and precision for most applications is not yet available and detains location based services from indoor areas. This is also due to missing comparability and standards in the field of indoor positioning, resulting in a large number of proprietary research prototypes of varying capabilities. In this paper we present a software environment for testing and comparing sensor fusion algorithms in indoor positioning scenarios. For this purpose an extendable tool for evaluating accuracy, precision, robustness, complexity, and storage is designed and the results from a first implementation presented and discussed.}
    }

  • M. Maier, F. Dorfmeister, M. Schönfeld, and M. Kessel, „A Tool for Visualizing and Editing Multiple Parallel Tracks of Time Series Data from Sensor Logs,“ in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 99-108.
    [BibTeX] [Abstract]

    In the last couple of years, the number of smartphone users has proliferated. As smartphones contain a lot of different sensors, research interest in algorithms combining data of several sensors to derive meaningful information about a user’s context, e.g. her location, is increasing. Ideas for reasonable algorithms often can be found by looking at examples of raw (or somehow pre-processed) sensor data. Still, the research community lacks a simple means to intuitively work with several parallel tracks of time series data. We present a tool which can be used to visualize and edit time dependent data from various sensors along with ground truth recordings like audio or video files. It is complemented by an optional application for logging all kinds of sensor data on Android devices. The tool has already been used to analyze a large data set containing hundreds of walking traces, intended to improve pedestrian dead reckoning algorithms.

    @inproceedings{paralleltrackstool,
    title = {A Tool for Visualizing and Editing Multiple Parallel Tracks of Time Series Data from Sensor Logs},
    author = {Marco Maier and Florian Dorfmeister and Mirco Schönfeld and Moritz Kessel},
    booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    year = {2012},
    pages = {99-108},
    abstract = {In the last couple of years, the number of smartphone users has proliferated. As smartphones contain a lot of different sensors, research interest in algorithms combining data of several sensors to derive meaningful information about a user's context, e.g. her location, is increasing. Ideas for reasonable algorithms often can be found by looking at examples of raw (or somehow pre-processed) sensor data. Still, the research community lacks a simple means to intuitively work with several parallel tracks of time series data. We present a tool which can be used to visualize and edit time dependent data from various sensors along with ground truth recordings like audio or video files. It is complemented by an optional application for logging all kinds of sensor data on Android devices. The tool has already been used to analyze a large data set containing hundreds of walking traces, intended to improve pedestrian dead reckoning algorithms.}
    }

2010

  • M. Dürr, M. Werner, and M. Maier, „Re-Socializing Online Social Networks,“ in 2010 IEEE/ACM International Conference on Green Computing and Communications (GreenCom 2010) & International Conference on Cyber, Physical and Social Computing (CPSCom 2010), 2010, pp. 786-791. doi:10.1109/GreenCom-CPSCom.2010.18
    [BibTeX] [Download PDF]
    @inproceedings{resocial,
    title = {Re-Socializing Online Social Networks},
    author = {Michael Dürr and Martin Werner and Marco Maier},
    booktitle = {2010 IEEE/ACM International Conference on Green Computing and Communications (GreenCom 2010) \& International Conference on Cyber, Physical and Social Computing (CPSCom 2010)},
    year = {2010},
    month = {Dec.},
    pages = {786 -791},
    doi = {10.1109/GreenCom-CPSCom.2010.18},
    url = {http://dx.doi.org/10.1109/GreenCom-CPSCom.2010.18}
    }