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Studiens syfte var att analysera hur svensk dags- och kvällspress framställer narkotikabrukare. Metoden som användes för att besvara syfte och frågeställningar var en kritisk diskursanalys. Studiens teoretiska grund var socialkonstruktionism och kritisk diskursanalys i relation till Goldbergs (2010) stämplingsteoretiska modell. Resultatet visade på beskrivningar av narkotikabrukare som kriminella, utsatta, offer och beroende. Vad som också framkom var en bild av narkotikabrukare som en helt vanlig person, en Svensson med familj, barn och fast anställning. De diskurser som uttyddes var en förövardiskurs, en offerdiskurs och en normaliseringsdiskurs. Utifrån den stämplingsteoretiska modellen kunde det tolkas som att både offerdiskursen och förövardiskursen är stigmatiserande och således med i skapandet av avvikare medan normaliseringsdiskursen kan sägas vara icke-stigmatiserande för narkotikabrukare. / The purpose of the study was to analyse how the Swedish daily and evening press portraysdrug users. The method used to answer the purpose and questions of the study was a critical discourse analysis. The theoretical basis of the study was social constructionism and critical discourse analysis in relation to Goldberg's (2010) stigma theory. The results showed descriptions of drug users as criminals, victims and addicts. What also emerged was an image of drug users as an ordinary person with a family, children and full-time employment. The interpreted discourses were an offender discourse, a victim discourse, and a normalization discourse. Based on the stigma theory, it could be interpreted that both the victim discourse and the perpetrator discourse are stigmatizing and thus involved in the creation of deviants while the normalization discourse can be said to be nonstigmatizing for drug users.

Sustainable efficient lighting has become as one of the most important issues in the office environment In Sweden, energy demand for lighting corresponds to 20% of the total electricity used in office buildings (1), while It has been estimated that lighting accounts for about 20% of the total power generation of the world (2). This thesis investigates how to make lighting in offices more sustainable and focuses on energy efficiency, to save energy through creating guidelines related to light source technologies, lighting control systems and the user preferences. Then those guidelines are applied to an existing office through suggesting a new lighting design. The existing office in this case is the ÅF company 10th office floor located in Stockholm, Sweden. This investigation methodology consists of two main parts literature review and Project (case) study. In the first part, methods used are a combination of literature review related to saving energy through sustainability in lighting and how light source technology, lighting control systems and the effect of user behavior could help to create more energy efficient lighting systems. In the second part, the methods are qualitative such as surveys, quantitative methods and personal observations. The used methods helped to create guidelines for the new suggested lighting design for ÅF 10 th office floor part. The Results shows that the new suggested lighting design saves energy up to 31.96% more than the current lighting situation.

<p>The study investigates the user experience of visually impaired people using screen readers, concentrating on their accessibility and usability when navigating digital content. Screen readers are indispensable instruments for the blind and visually impaired, facilitating the completion of online tasks and access to information. While screen readers offer benefits such as customization and accessibility, they also present users with challenges such as cognitive burden, sequential navigation, and limitations with multimedia content.</p><p>The research takes a user-centric approach, taking into account the particular requirements and preferences of visually impaired users. By conducting empirical research, the study gains valuable insights into the experiences, requirements, and pain points of screen reader users. The objective is to identify areas for enhancement and create solutions that enhance the user's efficiency and satisfaction.</p><p>Recognizing the diverse subcategories within the visually impaired population, the thesis argues for design approaches that are tailored to specific needs. In addition, the incorporation of existing artificial intelligence systems, such as image caption generation and text extraction, is investigated to improve the functionality and usability of screen readers.</p><p>Through this research, the thesis emphasizes the significance of creating digital content that is both functional and accessible. By embracing the curb cut effect and incorporating empirical research findings, developers can cultivate a more inclusive and equitable online environment for all users, thereby promoting inclusivity and ensuring that visually impaired users can effectively interact with digital content.</p>

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Cycling as a mode of transportation has been recording an upward trend in both the U.S. and Europe. Unfortunately, the safety of cyclists has been a point of growing concern. Data from the National Highway Traffic Safety Administration (NHTSA) show that the crashes that occur during the events of motorists overtaking cyclists was one of the leading categories involving cyclists in fatal crashes. In support of the efforts to understand the driving behavior of drivers of motorized vehicles while overtaking cyclists, this research project is aimed at developing an algorithm to identify the overtaking events. Most existing quantitative studies on cycling safety leverage instrumented bicycles or vehicles with sensors for extracting naturalistic driving trajectories. Whereas we use data from a recent research that provides naturalistic driving trajectories of road users collected at select intersections in urban areas in Germany using drones equipped with cameras. Using these videos with a data frequency of 25 Hz, the authors of this study have output inD dataset. The inD dataset contains trajectories of road users that are captured in form of coordinates on a two-dimensional plane obtained from the ariel or bird's eye view of the road. Additionally, the data also captures velocity, acceleration, heading angles, dimensions of driver's vehicle etc. Overtaking can be thought of as four phases of approaching, steering away, passing, and returning. Using the inD dataset, we have developed an algorithm to identify events when a driver of motor vehicle overtakes a cyclist. This work fits into our broader goal to contribute to the body of knowledge for improving road safety of cyclists. The work is expected to provide inputs to governmental/ traffic authorities in aspects such as design of intersections and design of bicycle lanes by providing insights into overtaking events. [from Indroduction]

Mobility has changed in recent years in cities worldwide, th.anks to tb.e strong rise in vehicles of micromobility. Bicycle riding is the most widespread micromobility transport mode, followed by stand-up electric scooters (e-scooters). This increase in its use has also led to an increase in related crashes. Both cyclists and e-scooter riders are vulnerable road users and are lik.ely to sustain severe injuries in crashes, especially with motor vehicles. The crashes consequences involving cyclists and other micromobility users have already investigated using numerical simulation software, such as MADYMO and PC-Crash. Most of them have been focused on bicycles and electric bicycles, whereas only few of tbem have analyzed e-scooter crashes consequences. Posirisuk: et al. [1] carried out a computational prediction ofhead-ground impact k:inematics :in e-scooter falls. Ptak et al. [2] analyzed the e-scooter user kinematics after a crash against SUV when the e-scooter chives into the sidefront of tbe vehicle, a side B-pillar crash and a frontal impact initiated by tbe e-scooter to tbe front-end of the vehicle. However, they did not study the consequ.ences of a car to e-scooter side impact crashes. Xu et al. [3] did study these crashes but considering electric self-balancing scooters that are less widespread than e-scooters. Current study focuses on the consequences of a car to micromobility user (cyclist and e-scooter rider) side impact crashes. The analysis is based on numerical simulations with PC-Crash software.

IAB one solution of micromobility, e-scooters have become a trend in Germany. However, the concems about the safety of e-scooter riders, influence on pedestrians and the parking issues are growing. In 2020, 2,155 e-scooters involved personal injury accidents were recorded in Germany. The number rose to 5,502 in 2021 meaning an increase of 155.31 %. Compared to cyclists (incl. pedelec cyclists), the increasing rate of personal injury accidents in the same period decreased by 8.75 % [1, 2]. Against the background of accidents with e-scooters in cities, prior studies analysed severity and patterns of injuries caused by such accidents [3, 4]. In addition, comparisons are drawn to the consequences of accidents with other vehicles [5, 6]. Some studies also consider the risk of injuries in relation to the miles travelled [7]. The studies provide valuable findings but the approaches focus on the severe consequences of occurred accidents. At the same time, compared to bicycles, the centre of gravity of e-scooters is lower, they are more manoeuvrable and can still reach speeds of up to 20 km/h [8]. The question remains, if these vehicle characteristics are associated with different interaction behaviour. Hence, the aim of the present study is to reveal the riding behaviour profile in different contexts and investigate e-scooter riders' criticality in interaction behaviour compared with cyclists using surrogate safety measures. We aim to figure out if the interaction behaviour of the two modes differ and what the effects of potential differences are for safety considerations in the system of active mobility.

This thesis explores the use of multimodality to communicate retrieved results of Internet search engines. The investigation aimed to investigate suitable multimodal metaphors which would increase the level of usability of Internet search engine interfaces and enhance users` experience in the search activity. The study consisted of three experiments based on questionnaires and Internet search activities with a set of text-based and multimodal interfaces. These interfaces were implemented in two browsing platforms, named AVBRO and AVBRO II. In the first experiment, the efficiency of specific multimodal metaphors to communicate additional information of retrieved results was investigated. The experiment also sought to obtain users` views of these metaphors with a questionnaire. An experimental multimodal interface of the AVBRO platform, which communicated additional information with a combination of three 2D graphs and musical stimuli, was used as a basis for the experiment, together with the Google search engine. The results obtained led to the planning of a second experiment. The aim of this experiment was to obtain and compare the level of usability of four different experimental multimodal interfaces and one traditional text-based interface, all implemented in the AVBRO II platform. Effectiveness, efficiency and users` satisfaction were used as criteria to evaluate the usability of these interfaces. In the third and final experiment the usability analysis of a traditional text-based interface and the two most suitable experimental multimodal interfaces of the AVBRO II platform was further investigated. Learnability, errors rate, efficiency, memorability and users` satisfaction were used as criteria to evaluate the usability of these interfaces. The analysis of the results obtained from these experiments provided the basis for a set of design guidelines for the development of usable interfaces based on a multimodal approach.

<p>This thesis considers wireless multi-input multi-output (MIMO) communication systems in block flat-fading environments. It develops novel designs of transmission and reception schemes for single-user and multi-user systems. The designs are developed under different models for the information about the communication channel that is available at the transmitter.</p> <p>For single-user systems, the thesis studies the class of non-linear MIMO transceivers that implement sequential interference (pre-) subtraction, namely transceivers with Tomlinson-Harashima precoding (THP) and transceivers with decision feedback equalization (DFE). For these transceivers a novel design framework is developed to unify the design of these two dual systems when channel state information (CSI) is available at both the transmitter and the receiver. The framework encompasses a broad range of performance criteria, and generates closed-form expressions for the optimal designs under these criteria. The framework reveals that a single transceiver design is optimal for a large subclass of these performance criteria and shows that this unique optimal design is (strictly) superior to the corresponding optimal linear transceiver for the same performance criterion. The framework also characterizes another class of design criteria for which the optimal non-linear transceiver reduces to the optimal linear transceiver for the same criterion. This novel design framework brings the design of non-linear MIMO transceivers to a level of maturity similar to the linear counterparts, and will impact the design of practical wireless communication systems that implement these interference subtraction schemes. The framework is then generalized to the case of DFE transceivers that satisfy an additional zero-forcing (ZF) constraint and operate in a "limited feedback" regime in which CSI is available only to the receiver and there is a limited rate feedback channel between the receiver and the transmitter. The proposed limited feedback system is the first that involves a "precoded" DFE transceiver.</p> <p> The multi-user part of the thesis develops multi-user transceivers that are robust to uncertainties in the available information about the users' channels. These uncertainties are inevitable in most practical multi-user communication systems, and can result in significant performance degradation.</p> <p> The first component of the multi-user part develops robust broadcast channel transceivers with quality of service (QoS) requirements for communication scenarios with bounded channel uncertainty at the transmitter. It formulates design problems for QoS requirements that can be expressed as constraints on the signal-to-interference-plus-noise-ratio (SINR) of each user, or as constraints on the mean square error (MSE) each user's received signal. For both formulations, convex and efficiently solvable design approaches are proposed. These design approaches are used to derive solutions to other related design problems, such as robust counterparts of the fair broadcasting problem.</p> <p> The second component of the multi-user part develops robust designs for multiuser transceivers that minimize different MSE criteria subject to a power constraint. The designs are obtained for different models of channel uncertainty: stochastic uncertainty models and bounded uncertainty models. For each channel uncertainty model, the robust multi-user designs are developed for both linear and non-linear MIMO transceivers, for both broadcast channels (BC) and multiple access channels (MAC).</p> <p>Simulation studies demonstrate the impact of the proposed robust designs on the performance of multi-user systems, and show that by incorporating robustness in the design one can significantly reduce the sensitivity of these systems to channel uncertainty and mitigate its deleterious effects.</p> / Thesis / Doctor of Philosophy (PhD)