@phdthesis{Hosp2015, author = {Hosp, Sven}, title = {Modifizierte Cross-Party Codes zur schnellen Mehrbit-Fehlerkorrektur}, pages = {105}, year = {2015}, language = {de} } @phdthesis{Koehlmann2016, author = {K{\"o}hlmann, Wiebke}, title = {Zug{\"a}nglichkeit virtueller Klassenzimmer f{\"u}r Blinde}, publisher = {Logos}, address = {Berlin}, isbn = {978-3-8325-4273-3}, pages = {i-x, 310, i-clxxvi}, year = {2016}, abstract = {E-Learning-Anwendungen bieten Chancen f{\"u}r die gesetzlich vorgeschriebene Inklusion von Lernenden mit Beeintr{\"a}chtigungen. Die gleichberechtigte Teilhabe von blinden Lernenden an Veranstaltungen in virtuellen Klassenzimmern ist jedoch durch den synchronen, multimedialen Charakter und den hohen Informationsumfang dieser L{\"o}sungen kaum m{\"o}glich. Die vorliegende Arbeit untersucht die Zug{\"a}nglichkeit virtueller Klassenzimmer f{\"u}r blinde Nutzende, um eine m{\"o}glichst gleichberechtigte Teilhabe an synchronen, kollaborativen Lernszenarien zu erm{\"o}glichen. Im Rahmen einer Produktanalyse werden dazu virtuelle Klassenzimmer auf ihre Zug{\"a}nglichkeit und bestehende Barrieren untersucht und Richtlinien f{\"u}r die zug{\"a}ngliche Gestaltung von virtuellen Klassenzimmern definiert. Anschließend wird ein alternatives Benutzungskonzept zur Darstellung und Bedienung virtueller Klassenzimmer auf einem zweidimensionalen taktilen Braille-Display entwickelt, um eine m{\"o}glichst gleichberechtigte Teilhabe blinder Lernender an synchronen Lehrveranstaltungen zu erm{\"o}glichen. Nach einer ersten Evaluation mit blinden Probanden erfolgt die prototypische Umsetzung des Benutzungskonzepts f{\"u}r ein Open-Source-Klassenzimmer. Die abschließende Evaluation der prototypischen Umsetzung zeigt die Verbesserung der Zug{\"a}nglichkeit von virtuellen Klassenzimmern f{\"u}r blinde Lernende unter Verwendung eines taktilen Fl{\"a}chendisplays und best{\"a}tigt die Wirksamkeit der im Rahmen dieser Arbeit entwickelten Konzepte.}, language = {de} } @phdthesis{Wust2015, author = {Wust, Johannes}, title = {Mixed workload managment for in-memory databases}, pages = {VIII, 167}, year = {2015}, language = {en} } @phdthesis{Neuhaus2017, author = {Neuhaus, Christian}, title = {Sicherheitsmechanismen f{\"u}r dienstbasierte Softwaresysteme}, school = {Universit{\"a}t Potsdam}, pages = {183}, year = {2017}, language = {de} } @phdthesis{Kilic2016, author = {Kilic, Mukayil}, title = {Vernetztes Pr{\"u}fen von elektronischen Komponenten {\"u}ber das Internet}, school = {Universit{\"a}t Potsdam}, pages = {104, XVI}, year = {2016}, language = {de} } @phdthesis{Hagedorn2016, author = {Hagedorn, Benjamin}, title = {Konzepte und Techniken zur servicebasierten Visualisierung von geovirtuellen 3D-Umgebungen}, school = {Universit{\"a}t Potsdam}, pages = {140}, year = {2016}, language = {de} } @phdthesis{Heinze2015, author = {Heinze, Theodor}, title = {Analyse von Patientendaten und Entscheidungsunterst{\"u}tzung in der Telemedizin}, school = {Universit{\"a}t Potsdam}, pages = {173}, year = {2015}, language = {de} } @phdthesis{Weber2015, author = {Weber, Edzard}, title = {Erarbeitung einer Methodik der Wandlungsf{\"a}higkeit}, school = {Universit{\"a}t Potsdam}, pages = {471}, year = {2015}, language = {de} } @phdthesis{Albrecht2013, author = {Albrecht, Alexander}, title = {Understanding and managing extract-transform-load systems}, pages = {107}, year = {2013}, language = {en} } @phdthesis{Kaufmann2015, author = {Kaufmann, Benjamin}, title = {High performance answer set solving}, pages = {182}, year = {2015}, language = {en} } @phdthesis{Schacht2014, author = {Schacht, Alexander}, title = {Konzepte und Strategien mobiler Plattformen zur Erfassung und Anlayse von Vitalparametern in heterogenen Telemonotoring-Systemen}, pages = {215}, year = {2014}, language = {de} } @phdthesis{Tiwari2019, author = {Tiwari, Abhishek}, title = {Enhancing Users' Privacy: Static Resolution of the Dynamic Properties of Android}, school = {Universit{\"a}t Potsdam}, pages = {xiii, 111}, year = {2019}, abstract = {The usage of mobile devices is rapidly growing with Android being the most prevalent mobile operating system. Thanks to the vast variety of mobile applications, users are preferring smartphones over desktops for day to day tasks like Internet surfing. Consequently, smartphones store a plenitude of sensitive data. This data together with the high values of smartphones make them an attractive target for device/data theft (thieves/malicious applications). Unfortunately, state-of-the-art anti-theft solutions do not work if they do not have an active network connection, e.g., if the SIM card was removed from the device. In the majority of these cases, device owners permanently lose their smartphone together with their personal data, which is even worse. Apart from that malevolent applications perform malicious activities to steal sensitive information from smartphones. Recent research considered static program analysis to detect dangerous data leaks. These analyses work well for data leaks due to inter-component communication, but suffer from shortcomings for inter-app communication with respect to precision, soundness, and scalability. This thesis focuses on enhancing users' privacy on Android against physical device loss/theft and (un)intentional data leaks. It presents three novel frameworks: (1) ThiefTrap, an anti-theft framework for Android, (2) IIFA, a modular inter-app intent information flow analysis of Android applications, and (3) PIAnalyzer, a precise approach for PendingIntent vulnerability analysis. ThiefTrap is based on a novel concept of an anti-theft honeypot account that protects the owner's data while preventing a thief from resetting the device. We implemented the proposed scheme and evaluated it through an empirical user study with 35 participants. In this study, the owner's data could be protected, recovered, and anti-theft functionality could be performed unnoticed from the thief in all cases. IIFA proposes a novel approach for Android's inter-component/inter-app communication (ICC/IAC) analysis. Our main contribution is the first fully automatic, sound, and precise ICC/IAC information flow analysis that is scalable for realistic apps due to modularity, avoiding combinatorial explosion: Our approach determines communicating apps using short summaries rather than inlining intent calls between components and apps, which requires simultaneously analyzing all apps installed on a device. We evaluate IIFA in terms of precision, recall, and demonstrate its scalability to a large corpus of real-world apps. IIFA reports 62 problematic ICC-/IAC-related information flows via two or more apps/components. PIAnalyzer proposes a novel approach to analyze PendingIntent related vulnerabilities. PendingIntents are a powerful and universal feature of Android for inter-component communication. We empirically evaluate PIAnalyzer on a set of 1000 randomly selected applications and find 1358 insecure usages of PendingIntents, including 70 severe vulnerabilities.}, language = {en} } @phdthesis{Felgentreff2017, author = {Felgentreff, Tim}, title = {The Design and Implementation of Object-Constraint Programming}, school = {Universit{\"a}t Potsdam}, pages = {183}, year = {2017}, language = {en} } @phdthesis{Fudickar2014, author = {Fudickar, Sebastian}, title = {Sub Ghz transceiver for indoor localisation of smartphones}, school = {Universit{\"a}t Potsdam}, pages = {IV, 167}, year = {2014}, language = {en} } @phdthesis{Schindler2016, author = {Schindler, Sven}, title = {Honeypot Architectures for IPv6 Networks}, school = {Universit{\"a}t Potsdam}, pages = {164}, year = {2016}, language = {en} } @phdthesis{Jung2015, author = {Jung, J{\"o}rg}, title = {Efficient credit based server load balancing}, school = {Universit{\"a}t Potsdam}, pages = {353}, year = {2015}, language = {en} } @phdthesis{Hoellerer2016, author = {H{\"o}llerer, Reinhard}, title = {Modellierung und Optimierung von B{\"u}rgerdiensten am Beispiel der Stadt Landshut}, school = {Universit{\"a}t Potsdam}, pages = {244}, year = {2016}, abstract = {Die Projektierung und Abwicklung sowie die statische und dynamische Analyse von Gesch{\"a}ftsprozessen im Bereich des Verwaltens und Regierens auf kommunaler, L{\"a}nder- wie auch Bundesebene mit Hilfe von Informations- und Kommunikationstechniken besch{\"a}ftigen Politiker und Strategen f{\"u}r Informationstechnologie ebenso wie die {\"O}ffentlichkeit seit Langem. Der hieraus entstandene Begriff E-Government wurde in der Folge aus den unterschiedlichsten technischen, politischen und semantischen Blickrichtungen beleuchtet. Die vorliegende Arbeit konzentriert sich dabei auf zwei Schwerpunktthemen: > Das erste Schwerpunktthema behandelt den Entwurf eines hierarchischen Architekturmodells, f{\"u}r welches sieben hierarchische Schichten identifiziert werden k{\"o}nnen. Diese erscheinen notwendig, aber auch hinreichend, um den allgemeinen Fall zu beschreiben. Den Hintergrund hierf{\"u}r liefert die langj{\"a}hrige Prozess- und Verwaltungserfahrung als Leiter der EDV-Abteilung der Stadtverwaltung Landshut, eine kreisfreie Stadt mit rund 69.000 Einwohnern im Nordosten von M{\"u}nchen. Sie steht als Repr{\"a}sentant f{\"u}r viele Verwaltungsvorg{\"a}nge in der Bundesrepublik Deutschland und ist dennoch als Analyseobjekt in der Gesamtkomplexit{\"a}t und Prozessquantit{\"a}t {\"u}berschaubar. Somit k{\"o}nnen aus der Analyse s{\"a}mtlicher Kernabl{\"a}ufe statische und dynamische Strukturen extrahiert und abstrakt modelliert werden. Die Schwerpunkte liegen in der Darstellung der vorhandenen Bedienabl{\"a}ufe in einer Kommune. Die Transformation der Bedienanforderung in einem hierarchischen System, die Darstellung der Kontroll- und der Operationszust{\"a}nde in allen Schichten wie auch die Strategie der Fehlererkennung und Fehlerbehebung schaffen eine transparente Basis f{\"u}r umfassende Restrukturierungen und Optimierungen. F{\"u}r die Modellierung wurde FMC-eCS eingesetzt, eine am Hasso-Plattner-Institut f{\"u}r Softwaresystemtechnik GmbH (HPI) im Fachgebiet Kommunikationssysteme entwickelte Methodik zur Modellierung zustandsdiskreter Systeme unter Ber{\"u}cksichtigung m{\"o}glicher Inkonsistenzen >Das zweite Schwerpunktthema widmet sich der quantitativen Modellierung und Optimierung von E-Government-Bediensystemen, welche am Beispiel des B{\"u}rgerb{\"u}ros der Stadt Landshut im Zeitraum 2008 bis 2015 durchgef{\"u}hrt wurden. Dies erfolgt auf Basis einer kontinuierlichen Betriebsdatenerfassung mit aufwendiger Vorverarbeitung zur Extrahierung mathematisch beschreibbarer Wahrscheinlichkeitsverteilungen. Der hieraus entwickelte Dienstplan wurde hinsichtlich der erzielbaren Optimierungen im dauerhaften Echteinsatz verifiziert.}, language = {de} } @phdthesis{Schnjakin2014, author = {Schnjakin, Maxim}, title = {Cloud-RAID}, pages = {137}, year = {2014}, language = {de} } @phdthesis{Wang2016, author = {Wang, Cheng}, title = {Deep Learning of Multimodal Representations}, school = {Universit{\"a}t Potsdam}, pages = {142}, year = {2016}, language = {en} } @phdthesis{Saleh2016, author = {Saleh, Eyad}, title = {Securing Multi-tenant SaaS Environments}, school = {Universit{\"a}t Potsdam}, pages = {108}, year = {2016}, abstract = {Software-as-a-Service (SaaS) offers several advantages to both service providers and users. Service providers can benefit from the reduction of Total Cost of Ownership (TCO), better scalability, and better resource utilization. On the other hand, users can use the service anywhere and anytime, and minimize upfront investment by following the pay-as-you-go model. Despite the benefits of SaaS, users still have concerns about the security and privacy of their data. Due to the nature of SaaS and the Cloud in general, the data and the computation are beyond the users' control, and hence data security becomes a vital factor in this new paradigm. Furthermore, in multi-tenant SaaS applications, the tenants become more concerned about the confidentiality of their data since several tenants are co-located onto a shared infrastructure. To address those concerns, we start protecting the data from the provisioning process by controlling how tenants are being placed in the infrastructure. We present a resource allocation algorithm designed to minimize the risk of co-resident tenants called SecPlace. It enables the SaaS provider to control the resource (i.e., database instance) allocation process while taking into account the security of tenants as a requirement. Due to the design principles of the multi-tenancy model, tenants follow some degree of sharing on both application and infrastructure levels. Thus, strong security-isolation should be present. Therefore, we develop SignedQuery, a technique that prevents one tenant from accessing others' data. We use the Signing Concept to create a signature that is used to sign the tenant's request, then the server can verifies the signature and recognizes the requesting tenant, and hence ensures that the data to be accessed is belonging to the legitimate tenant. Finally, Data confidentiality remains a critical concern due to the fact that data in the Cloud is out of users' premises, and hence beyond their control. Cryptography is increasingly proposed as a potential approach to address such a challenge. Therefore, we present SecureDB, a system designed to run SQL-based applications over an encrypted database. SecureDB captures the schema design and analyzes it to understand the internal structure of the data (i.e., relationships between the tables and their attributes). Moreover, we determine the appropriate partialhomomorphic encryption scheme for each attribute where computation is possible even when the data is encrypted. To evaluate our work, we conduct extensive experiments with di↵erent settings. The main use case in our work is a popular open source HRM application, called OrangeHRM. The results show that our multi-layered approach is practical, provides enhanced security and isolation among tenants, and have a moderate complexity in terms of processing encrypted data.}, language = {en} }