TY - THES A1 - Nolte, Johannes T1 - Untersuchung der Vorgehensweise ausgewählter Internetplattformen gegen gefälschte Online-Bewertungen N2 - Diese Arbeit dokumentiert ein Experiment zur Untersuchung des Umgangs von Facebook, Google Maps, Google Play Store und Zalando mit gefälschten Bewertungen („Opinion Spam“). Es wurde untersucht, ob die Plattformen im Rahmen dieser Arbeit abgegebene gefälschte Bewertungen veröffentlichen. Dazu wurden je Plattform 24 unterschiedlich authentisch wirkende Konten erstellt. Mit diesen wurden je 48 gefälschte Bewertungen nach folgenden Kriterien abgegeben: 1) Kopierte Produkt-/Ortsbeschreibung oder Werbesprache 2) Aussagen ohne Produkt-/Ortsbezug oder inhaltliche Fehler 3) Blindtexte oder sehr viele Rechtschreibfehler 4) eine Meinung verknüpft mit der Aussage, dass der Bewertende das Produkt/den Ort nicht kennt. Innerhalb von 14 Tagen wurde mehrmals überprüft, ob eine Bewertung freigeschaltet oder gelöscht wurde. Bei Facebook wurden 6,7% der abgegebenen Bewertungen innerhalb der ersten 14 Tage gelöscht. Nachdem die verbleibenden Bewertungen der Plattform gemeldet wurden, waren es 47,7%. Bei Google Maps wurden 4,2% entfernt, im Google Play Store 12,5% (bei beiden keine Änderung durch Melden). Bei Zalando (kein Melden möglich) war die eigenständige Löschquote mit 43,8% mit Abstand am höchsten. Besonders häufig wurden im Experiment Blindtexte gelöscht. Positive und negative Bewertungen wurden nahezu gleich oft entfernt. Bewertungen von Konten mit simulierter Nutzerinteraktion wurden häufiger gelöscht als Bewertungen von Konten ohne Nutzerinteraktion. Das Experiment hat gezeigt, dass sehr viele gefälschte Bewertungen, die eindeutig den Richtlinien der Plattformen widersprechen, nicht gelöscht wurden. Deren Sichtbarkeit variiert allerdings je nach Plattform und Produkt/Ort stark. Der Aufwand für die Erstellung vieler Konten bei den Diensten ist überschaubar. Wenn Nutzer gefälschte Bewertungen nach den im Experiment untersuchten Kriterien abgeben wollen, werden sie von den Plattformen daran wenig gehindert. N2 - This bachelor thesis contains the documentation of an experiment to evaluate how Facebook, Google Maps, Google Play Store and Zalando deal with fake reviews (“opinion spam”). Measured was whether the platforms publish or delete fake reviews submitted in the context of this work. For this purpose, 24 accounts with different attributes according to age and user interaction were created on each platform. With those accounts 48 reviews per platform were submitted based on the following criteria: 1) Copied product/location description or advertising-language 2) reviews without product/location reference or contextual errors 3) Blind texts or many spelling mistakes 4) reviews which contain an opinion but state that the author does not know the product/location. 6.7% of the reviews submitted to Facebook were deleted within the first 14 days, 47.7% after reporting the remaining reviews to Facebook. Google Maps deleted 4.2%, Google Play Store 12.5% (both showed no changes after reporting). Zalando (no reporting possible) has the by far highest independent deletion rate with 43.8%. Blind texts were most often deleted during the experiment. Positive and negative ratings were deleted almost the same number of times. Reviews from accounts with simulated user interaction were deleted more often than reviews from accounts without user interaction. The experiment showed that many fake reviews, which contradict the guidelines of the platforms, were not deleted. But their visibility varies depending on platform and product/location. The creation of many accounts at the services does not require too much effort. If users want to publish fake reviews according to the criteria used in the experiment, the platforms do not really hinder them. KW - Gefälschte Bewertungen KW - Opinion spam KW - Fake reviews Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2126 ER - TY - THES A1 - Dogotari, Marcel T1 - Hardware Design and RF Performance Evaluation of a Long Range 2.4 GHz Radio Module N2 - Low–power, long–range wireless solutions are needed for transmission of environmental and industrial monitoring data from remote, battery–driven sensors. Chirp spread spectrum (CSS) modulation techniques are able to meet these requirements. A CSS–based radio module was designed to operate in the 2.4 GHz frequency band, whose advantages are worldwide availability, lack of duty–cycle restrictions and a broad spectrum. The module’s power consumption is satisfactory, but its range has to be improved. The accuracy of time-of-flight (ToF) distance estimation, an extra feature of the module, has not been evaluated. Impedance matching, transmission lines and printed circuit board design are among the practical aspects discussed, while ToF ranging and orthogonality of CSS signals are considered from a theoretical point of view. KW - Long–range radio module KW - Printed circuit board design KW - Transmission lines and impedance matching KW - Chirp spread spectrum KW - Time-of-flight ranging Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2158 ER - TY - THES A1 - Lam, Hoi Ying T1 - Radar Signal Distortion caused by Directional Vibration of a 24 GHz FMCW System N2 - This thesis is an initial attempt to investigate the influence of mechanical vibrations on the 24 GHz FMCW radar developed by IMST GmbH and develop a simple vibration compensation model for the human tracking algorithm. The project objectives are to determine the radar signal distortion caused by vibrations theoretically, conduct simulations to evaluate the effects of vibrations on the human tracking process, and develop a basic model to compensate the disturbing vibrations. The single radar pulse simulations conclude that when the radar is vibrating at a low frequency, the signal would not be distorted if the change of phase of the intermediate frequency is less than half a resolution cell. While the results from the multiple radar pulses simulations reveal that factors like the SNR value, vibrating amplitude and the target’s velocity would influence the human tracking process. The higher the SNR value, vibrating amplitude and target’s velocity, the more the detected ghost targets when there is only one target presence. A signal demodulation method is then proposed which indicate the possibility in reducing the disturbance caused by the vibrations. KW - FMCW Radar KW - Vibration KW - Human Tracking KW - Simulation KW - Compensation Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2164 ER - TY - THES A1 - Keiffenheim, Jan T1 - Die Produktion von Audiodateien und deren Einbindung in Videospiele N2 - In this paper the production of audio file will be shown with examples, and how these can be put exemplarily into a video game. For this purpose different types of programs will be presented which can produce audio file. To show a small expenditure, affordable or free programs will be used for this paper. After that the paper shows how to exemplarily record and edit music, sound and voice. Finally a game engine will be used to demonstrate the inset and programming of the created audio files. This paper is especially for newcomers (and students) to introduce them to audio and sound design. With the practical instructions in this paper they can start to produce audio files by their own. N2 - In dieser Bachelorarbeit wird anhand von Beispielen die Produktion von Audiodateien gezeigt, und wie diese beispielhaft in ein Videospiel eingefügt werden können. Hierzu werden zunächst die verschiedenen Programmtypen präsentiert, mit denen Audiodateien produziert werden können. Um einen möglichst geringen Kostenaufwand zu zeigen, werden Programme benutzt, die kostenlos oder kostengünstig erworben werden können. Danach wird an Beispielen gezeigt, wie mit den ausgewählten Programmen Stimmen, Geräusche und Musik aufgenommen und bearbeitet werden können. Abschließend wird an einer Spiele-Engine vorgeführt, wie die erstellten Audiodateien ins Spiel eingefügt und einprogrammiert werden. Durch diese Bachelorarbeit sollen vor allem Neueinsteiger (und Studenten) an Audio und Sound Design herangeführt werden, sodass sie mit den praktischen Unterweisungen in dieser Arbeit selbst Audiodateien produzieren können. KW - Audiobearbeitung KW - Kostengünstige Mittel & einfache Methoden KW - Audio Programmierung KW - Musik KW - Geräusche KW - Stimme Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-3494 ER - TY - THES A1 - Prüm, Moritz T1 - Automated Hyperspectral Field Scanner for Vegetation Monitoring N2 - Vegetation monitoring is an important tool in a variety of fields, e.g. precision agriculture and plants’ phenotyping. The system design of existing non-invasive ground based systems is usually not open-source. Therefore, these systems cannot be reliably modified and thus are not suitable to advanced applications, such as prototyping of new sensors. This thesis describes the development of a ground based hyperspectral monitoring system for use in plant science and sensor testing. A well-documented and automated working prototype has been developed and initial tests show promising results. Further work in system modularity and redundancy is needed. KW - Embedded systems KW - Hyperspectral imaging KW - Low-power design KW - System integration KW - Vegetation monitoring Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2247 ER - TY - THES A1 - Hörnschemeyer, Heike T1 - Development of a Usability Capability Self-Assessment Tool for Improvement and Monitoring of Human-Centred Design in Small and Medium-Sized Companies N2 - Usability is an important quality aspect of software products. Today, companies need to be capable to develop software with good usability to stay competitive. This can be achieved by practicing human-centred design (HCD) during the development process. However, especially small and medium-sized software enterprises (SMEs) still practice HCD on a low level, if at all. This thesis explores whether and how the approach of process capability assessment can support SMEs with a systematic improvement of HCD. It is shown that a process capability assessment for usability at SMEs can only be successful, when the first steps of initiating HCD are al-ready done. Then, a process assessment approach seems to be useful to systematically improve the usability capability at SMEs. Based on this theoretical background, a usability capability self-assessment tool tailored for SMEs is developed. It has a simplified assessment procedure and uses the DIN EN ISO 9241-220 as reference model. The self-assessment tool was applied at two German software SMEs to test whether the approach is useful for SMEs and whether the reference model is suitable. The results indicate that the usability self-assessment tool is a promising approach for future SMEs as several interesting applications were identified. The chosen reference model seems to be an appropriate choice for a self-assessment; only the complex language used in the standard impedes the assessment. All in all, the thesis lays the foundation for a systematic approach to support SMEs with usability. KW - Self-assessment KW - Usability capability KW - Small and medium-sized enterprises KW - Process assessment KW - DIN EN ISO 9241-220 Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2433 ER - TY - THES A1 - Koch, Kerstin T1 - How to communicate UX requirements? Guidelines based on a systematic literature review and interview study N2 - This thesis addresses the question of a suitable way to communicate user requirements to an interdisciplinary team. UX professionals are responsible for communicating user needs and UX requirements in a clear and understandable way so that other team members such as software developers can work in a user-centric way. The thesis examines known forms of requirements specification and identifies possible challenges in communicating user needs with the help of a systematic literature review. Based on design patterns, possible solutions for these problems are developed. In an interview study, these solution proposals are compared with real scenarios and adapted. As a result, the thesis presents nine guidelines that UX professionals can use to communicate user requirements. The idea is to promote a good exchange with the other team members and suitable, short forms of specification. A key point was that these should always convey a reason or the user’s motivation for a requirement to provide meaningful context information to those who have never been in touch with the user. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-8843 ER - TY - THES A1 - Shrestha, Manjil T1 - Development of a Language Model for Medical Domain N2 - Language models are widely used as a representation of written language in various machine learning tasks, with the most commonly used model being Bidirectional Encoder Representations from Transformers (BERT). It was shown that the prediction quality strongly benefits from language model pre-training on domain-specific data. The publicly available models, though are always trained on Wikipedia, news or legal data, thereby missing the domain specific knowledge about medical terms. In this thesis, we will train a BERT language model on medical data and compare performance with domain-unspecific language models. The dataset used for this purpose is the Non-technical Summaries - International Statistical Classification of Diseases (NTS-ICD) task of classification of animal experiment descriptions into International Statistical Classification of Diseases (ICD) categories. KW - Mult-label classification KW - ICD-10 Codes KW - Fine-tuning KW - German BERT NTS classification KW - Transfer learning Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-7405 ER - TY - THES A1 - Adebiyi, Akinloluwa Iyanu T1 - Combining User Experience Design & Service Design: Theory meets Practice N2 - This thesis explores how UXD and SD can work together more seamlessly in practice. UXD and SD have a lot of similarities. This has led to confusion around the borders and overlaps of both fields. Therefore researchers called for more studies to clarify their relationship. Most recent studies suggested diverting from polishing single touchpoints; some studies and focussing on end-to-end journey and the customer. The thesis examines the underlying activities of existing theoretical approaches and the challenges of combining UXD and SD with the help of thematic analysis. A set of proposed strategies were developed based on a survey on current practices and challenges with practitioners and thematic analysis. As a result, the thesis presents four strategies that design teams can incorporate into their processes. The idea is to promote the creation of better quality products and services by harnessing the benefits of both fields. The key point was that these concepts are still broad and should be simplified into leaner modes that can be applied in daily activities. KW - User experience design KW - Service design KW - Design practice KW - Persona Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-16337 ER - TY - THES A1 - Meyer, Tobias T1 - Automatisierte Tests oberflächenbezogener Geschäftslogik mit simulierten Benutzereingaben N2 - A lack of stability and reliability in user interfaces leads to user dissatisfaction. If this dissatisfaction is a repeating occurence users loose trust in the software and the company behind it. In the long run this leads to a migration from existing users to competitors and less new customers. To combat these effects companies have to ensure their user interfaces are stable and reliable. The Schleupen AG provides a browserbased user interface to its customers, which is split into a display layer running in the browser and a logic layer running on the server. In this thesis an automated solution for finding such problems in the logic layer was developed and applied to a selected subset of user interfaces. The solution was able to find multiple issues with most of them representing possible stability problems. This showed that automated testing of user interfaces for stability and reliability is possible and worthwhile. KW - User experience KW - Propertybased testing KW - Test automation KW - Continuous feedback Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-8544 ER -