The use of visual data representation is increasing the possibilities to exchange information and communicate indifferent contexts all over the world. Communicating food wastage visually to influence consuming patterns isone of these possibilities. Food wastage is currently a much-prioritized topic in Sweden as well as globally due toits negative impacts on society, environment and the economy, and therefore there is much need to bringinnovative solutions supporting reduction of food waste. This thesis presents a qualitative research based on a casestudy of food waste management at Sala municipality in Sweden while exploring the current visual datarepresentation techniques and its further potential to make food waste management more sustainable. The researchframework used in this thesis is based on visual rhetoric and the innovation theories. The thesis analyzes foodwastage from an international perspective, its connection to sustainable development goals and how MatomaticAB uses a visual data representation tool to address food wastage.The thesis further explains how the users associated with Sala municipality interpret the existing tool, thechallenges they face and review their expectations to build a new visual data representation model. The results ofquestionnaires filled by user’s, state that 50% of the respondents understand the current tool to its full capacityand only 50% of the respondents are satisfied with the overall tool. When it comes to the choice of datapresentation 67% of the users showed interest in use of infographics instead of the conventional bar graphs, andtherefore some parameters like, making the tool more interesting using infographics, user friendly by limiting thedata displayed and interactive by giving user options to explore further as per their liking, were thought whiledesigning the new visual data representation model.

Background and Objective In stereotactic brain tumor biopsies, the combination of real-time fluorescence spectroscopy with the detection of microvascular perfusion using laser Doppler flowmetry provides an improved localization of the brain tumor while decreasing the risk of intra-cranial hemorrhage. The surgeon using the measurement probe is required to view signal values on a screen or usually, when her or his visual focus is directed at the patient, the verbal feedback of a biomedical engineer who is monitoring the measurement signals is needed. In this process possible important information can be overlooked and time is lost. The aim of the thesis was the development a visual and auditory user interface (UI) for use in stereotactic brain tumor biopsies. Materials and Methods The system translates the fluorescence intensity of protoporphyrin IX (PpIX) into sound and visual indicators that are easy and fast to recognize and transmits warning signals in case of signal error or the detection of microvascular perfusion. The increasing and de-creasing fluorescence values at tumor margins were reproduced to improve the precision of de-tecting varying fluorescence intensities when entering tumor tissue with color gradient models. The algorithm produced five signal values when specific fluorescence intensities were measured and compared at different wavelengths.For the development of the UI, a user-centered design was implemented. The user-, operating room- and safety requirements were gathered by communicating with the biomedical engineers and neurosurgeons who had experience in working with fluorescence guided brain tumor biop-sies. The requirements were considered when designing the UI’s features in LabVIEW and the auditory feedback was generated using OSC (Open Sound Control). The user interface intended to deliver measurement data to the user that triggered a high response accuracy by being easy to understand while inducing high user acceptance. The user interaction and function response accuracy of the visual and auditory interface were evaluated in statistical tests where operating room situations were mimicked. The user acceptance of the UI was evaluated. Results Signals for no, low (increasing and decreasing) and high fluorescence indicators, as well as two warning indicators for a blocked signal and vessel occurrence were represented visually and auditorially by the user interface. An intensity/time graph and intensity/wavelength graph, along with the option of recording measurement files and opening saved files allowed the inspec-tion of detailed measurement values. The user study exhibited auditory response accuracy of 95 ± 3% in the intuition test and 91±16% in a memory test. The testing of the response accuracy of the individual signal values displayed accurate responses in 84% to 100% of times a signal was played back. The user acceptance rating of the auditory and visual interface showed no negative results. Conclusion A UI was developed to visually and auditorially represent measurement values to a neurosurgeon performing a stereotactic brain tumor biopsy procedure and biomedical engineers monitoring the measurement signals. The visual display was successful in representing data in a way that was easy to understand. The auditory interface showed high response accuracies for the individual tones representing measurement values. The majority of the test subjects per-ceived the signals to be intuitive, easy to understand and easy to remember. The auditory and visual UI showed high user acceptance ratings, indicating that the user interface was useful and satisfactory in its application.