• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 1
  • Tagged with
  • 4
  • 4
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Youth, social media, and online safety: a holistic approach towards detecting and mitigating risks in online conversations

Ali, Shiza 23 May 2024 (has links)
Social media platforms have become a popular and inexpensive way for people to communicate with millions of others. However, this increased usage has also led to an increase in risks associated with it, such as cyberbullying, trolling, misinformation, and privacy abuse. Previous research in this field has mainly focused on isolated aspects of online risk detection, which can limit the effectiveness of these studies. To address these issues, this dissertation presents a more holistic approach to detecting and reducing harmful and abusive behavior online. To gain an initial understanding of the problem, we first present a mixed-method study of messages and media files shared in private conversations by youth to understand the risky communication experienced by them. We use these findings to determine which features can automatically detect unsafe private conversations and whether social media platforms can implement such a system given the recent move towards end-to-end encryption. We present an ensemble machine learning classifier to detect risks in private messages and how to incorporate child safety by design. In the second part of this thesis, we will explore ways to stay ahead of hate and toxicity, given the changing online behaviors. Toxic language changes over time, with aggressors inventing new insults and abusive terms that frequently target certain vulnerable communities, including women and minorities. We develop automated systems that, given an initial lexicon of toxic speech, can learn new and emerging toxic words by observing conversations on social networks. Lastly, we examine the cross-platform implications of employing risk detection systems online. Most of the research focuses only on malicious activity that occurs on one platform, which does not allow us to get a full picture of the problem. Users are obviously not bound to a single platform but can migrate to other online services for example, anecdotal evidence shows that once hateful users are banned from Twitter, they often move to Gab, an alternative social network with an open lack of moderation marketed as protection of "free speech". Consequently, we argue that moderation efforts should extend beyond safeguarding users on individual platforms and account for the potential adverse consequences of banning users from prominent platforms.
2

Pedestrian to Vehicle Communication: A Safe and Private Solution Proposal

Sanchez Carmona, Pablo January 2020 (has links)
Vehicle-to-vehicle communication (V2V) has become one of the most risingtechnologies in recent years, and due to the implementation of 5G different solutionshave begun to be designed that allow communication between vehiclesand pedestrians (V2P). V2P communication is a challenge for two reasons:the incompatibility of technologies, as well as the need to have a real-timecommunication (crucial when sending and receiving road hazard messages).This document presents a solution for pedestrian-to-vehicle communication,detecting pedestrian risk situations using the mobile phone sensors and messagesby the vehicles. An architecture and communication protocol is presented,to send warning messages with low delay in a secure and private waywithout harming efficiency. Two algorithms are used, one implemented in anAndroid application and another one in a server, with the purpose of detectingpedestrian misbehavior in the road and reducing the amount of direct messagesbetween the nodes of the system. / Kommunikation mellan fordonen (V2V) har blivit en av de mest stigande teknikernaunder de senaste åren, och på grund av implementeringen av 5G harolika lösningar börjat utformas som möjliggör kommunikation mellan fordonoch fotgängare (V2P). V2P-kommunikation är en utmaning av två skäl: teknikensinkompatibilitet, liksom behovet av att ha en kommunikation i realtid(avgörande när du skickar och tar emot meddelanden om vägfara). Detta dokumentpresenterar en lösning för kommunikation mellan fotgängare och fordon,från upptäckten av fotgängarsrisksituationer på vägen använder mobiltelefonsensorertill fordonen mottagande meddelanden. Ett fullständigt arkitekturochkommunikationsprotokoll presenteras för att skicka flera varningsmeddelandenmed minsta möjliga fördröjning och på ett säkert och privat sätt, utan attförlora systemets effektivitet. Dessutom används två algoritmer, en implementeradi en Android-applikation och en annan på en server, i syfte att upptäckauppförande av fotgängare på vägen och minska mängden direktmeddelandenmellan systemets noder.
3

E-Scooters appear on bike infrastructure: users and usage, conflicts and coexistence with cycling

Hardinghaus, Michael, Oostendorp, Rebekka 03 January 2023 (has links)
E-scooters are a rather new mode of transport. Nevertheless, in recent years lots of studies have been published. Replaced modes and consequential environmental impacts as well as specific injury pattern are important topics. Regarding shape, speed and usage, e-scooters are most similar to bikes. As a consequence, by law e-scooters use the same road space or infrastructure than bikes do. Concurrently, in recent years we experience a boom of cycling in cities and a significant expansion of the bike infrastructure. Requirements and frequency of usage on the bike infrastructure are growing in cities caused by increasingly diverse cyclists. At the same time, the bike infrastructure is subject new requirements and additional pressure due to the implementation of e-scooters. In Germany, allowing e-scooters on bike infrastructure can be seen as a paradigm shift since for the first time a motorized vehicle is allowed to use the infrastructure. On this background, interrelation between e-scooters and active mobility (walking and cycling) are very important for the future use of the infrastructure and the ongoing transformation of urban mobility. Hence, we use a multi-method approach to investigate these potential conflicts and draw conclusions for regulation as well as improvement in the system.
4

Backup opening of automatic doors in autonomous vehicles : A usability study

Edberg, Hanna, Schulz, Madelene January 2023 (has links)
Shared autonomous vehicles provide a solution for the future of sustainable and accessible transportation in urban areas, both in terms of social and environmental sustainability. However, these types of vehicles face different challenges in comparison to privately owned ones. For example, it is of greater importance that a shared autonomous vehicle can cater to a large number of users with different prerequisites such as age, limited movement and strength, or visual impairment.  In this project, methods, and interactions for creating a human-centered design solution for backup door opening of automatic doors in the shared autonomous vehicle CM1e have been investigated. The aim of the project is to support the development of safer autonomous vehicles by implementing a solution that is user-friendly and inclusive for a large number of users having different prerequisites. The project has been conducted in Gothenburg at the company China Euro Vehicle Technology (CEVT). At the end of the project, it is expected to deliver a viable mapping of use cases where the user needs to use a backup door opening solution or has to exit in a non-optimal way, pain points of the current solution for the mapped-out use cases, a well-informed and holistic approach to decide which use cases are most relevant to solve considering different criteria, and finally a feasible solution at a conceptual level, solving the most urgent use cases and pain points. This project has had a holistic approach and has focused on both the context and scenarios of usage and how this impacts the users and usability. The investigated area is rather complex having many functions and several mediums. This has also contributed to the project to consider delivering a solution that caters to a task (in this case, exiting a vehicle) rather than one individual interaction. To achieve this use cases have been generated along with user journeys with personas having different prerequisites. This to achieve an objective description of the current functions as well as a subjective description of its limitations depending on the prerequisites of the users. To generate a large number of ideas and select the most relevant ideas, the ideation phase has focused on co-creation with relevant stakeholders and also the enrichment of ideas. By using two different user tests, the proposed solution has been validated in order to create a valuable and credible result. The delivered result offers a solution for use cases where the user/rider needs to exit the vehicle, but the preconditions do not allow the user to do so e.g., to ensure the functionality of the doors. This was uncovered to sometimes keep the user in the vehicle during undesirable situations where the user wishes to exit. The proposed solution utilizes the function of a dead man switch to override the set preconditions and provide the user with control over the door opening process, enabling possible exit without the doors having to open a 100%. Included in the solution is also communication using interfaces and activation of the dead man switch functionality to create a user-centered, accessible, and safe backup door opening solution. The proposed solution is presented using CAD models and renderings in the shape of storyboards. / Delade autonoma fordon erbjuder en framtida lösning för hållbara och tillgängliga transportsystem i urbana miljöer, med avseende på både social- och ekologisk hållbarhet. Dessa fordon möter dock andra typer av utmaningar än privat ägda fordon, exempelvis behöver de tillgodose behoven hos ett större antal användare med olika förutsättningar så som ålder, begränsad rörlighet och styrka samt begränsad synförmåga.   I detta projekt har metoder och interaktioner för att skapa användarvänliga lösningar för reservöppning av automatiska bildörrar i det delade autonoma fordonet CM1e undersökts. Syftet med projektet är att stödja utvecklingen av säkra autonoma fordon genom att implementera användarvänliga och inkluderande lösningar för ett stort antal användare med olika förutsättningar. Projektet har bedrivits i Göteborg hos företaget China Euro Vehicle Technology (CEVT). I slutet av projektet är det förväntat att leverera en kartläggning av situationer när en reservöppning av dörrar kan vara relevant, vilka begräsningar som finns i nuvarande lösningar samt ett förslag på en lösning för reservöppning av dörrar. De levererade lösningsförslaget ska tillgodose de kartlagda situationerna där en reservöppning av dörrar behövs som inte täcks av de nuvarande lösningarna.   Tillvägagångsättet av projektet har lagt tyngd på att ha ett helikopterperspektiv med fokus på både situation och kontext samt hur detta påverkar användaren och användbarheten. Det undersökta området är komplext och har många funktioner samt olika medium, vilket också har bidragit till att projektet har förväntats att leverera en lösning som tillgodoser en handling (i detta fall att ta sig ut ur ett fordon) snarare än en enskild interaktion. För att uppnå detta har användningsfall genererats samt kompletterande användarresor med användare med olika förutsättningar. Detta för att uppnå både en objektiv beskrivning av nuvarande funktioner och en subjektiv beskrivning av dess begräsningar beroende på användarnas förutsättningar. För att generera idéer till en framtida idé har ett stort fokus lagts på samskapande med intressenter och berikning av idéer. För att sedan validera den förslagna lösningen har två olika användartest utförts.   Det levererade resultatet erbjuder en lösning på användningsfall där de automatiska bildörrarna har förmågan att öppnas men ej tillåter användaren att göra det på grund av olika skäl, exempelvis att bevara funktionaliteten i dörrarna. Detta kan leda till att användaren kan bli instängd i bilen under situationer när hen önskar ta sig ut. Den förslagna lösningen utnyttjar funktionen av dödmansbrytare för att överskrida de satta förutsättningarna (preconditions) för att tillåta öppning och ge användaren kontroll över öppningsprocessen av bildörren, samt erbjuda en möjlighet att ta sig ut ur fordonet utan att dörrarna behövs öppnas 100%. I lösningen inkluderas även kommunikation via skärmar (visuellt och audiellt) och aktivering av dödmansbrytar-funktionaliteten för att skapa en användarvänlig, tillgänglig och säker reservöppning. Detta presenteras genom CAD-modeller och renderingar i form av storyboards.

Page generated in 0.0303 seconds