Chalmers Open Digital Repository
Not a member yet
26247 research outputs found
Sort by
Visualizing AI-Supported Adaptivity in Command and Control Interfaces
No full textThe user interface of Command and Control (C2) systems allows the radar operators to interact with the system. It enables them to surveil, assess, and detect anomalies in the air, on land, and at sea, thereby gaining situational awareness. The systems are complex, processing vast amounts of information, which is reflected in the user interface. The large volume of information, in combination with the high workload demands, risks causing cognitive overload. This could potentially lead to degraded task performance and fatigue, which, in high-stakes contexts, can have serious consequences.
To address this issue, this thesis, conducted in collaboration with Saab Surveillance, investigates where AI-supported adaptivity can be implemented in C2 systems, and how it
should be visualized. The effects of the visualizations are investigated under varying workload to draw conclusions about efficiency and the operator’s mental workload.
The project achieved this through an iterative Research through Design approach, where user interviews and research of the systems led to the creation of visual prototypes within three categories of concepts. These were called Filter, Target Prio-List, and View. All of these concepts were evaluated with participants with operational experience. The results of which provided relevant feedback, showing various potential with all concepts, including possible improvements and future research.
An Adaptivity & Workload Test was developed and conducted, investigating operators' efficiency and Situational Awareness under various workloads. These were performed on
interfaces with and without an adaptive Filter, comparing the results. The results from the test indicated that, with a low workload, performance and Situational Awareness were similar between interfaces with and without a filter; however, participants perceived their control to be higher without the filter. For a high workload, the performance and Situational Awareness were better with the adaptive filter, as well as the participants’ feeling of control.
Concluded, the results indicated that an adaptive filter aids the operator under high workload. Target Prio-List and View were also seen to have potential, however, they need to be developed and tested further, similar to Filter, to be properly evaluated
Maritime Shipping Network Graph - a Model Derived from Vessel AIS Data Creating and evaluating a graph representation of maritime vessel traffic using AIS data
No full textMaritime shipping shoulders more than 90% of global trade. Data science and ML, another immensely profitable industry, currently experiences an unprecedented evolution of techniques. This project proposes novel methods that apply data science techniques to the domain of maritime shipping. The main objective of this project is to construct a graph closely modelling the global maritime shipping structure, from which analytics can be derived. The node set is constructed using a pipeline of Change Point Detection to identify preliminary waypoints and reduce data quantity, KDE is utilised for geographical density estimation and partitioning the AIS data into different density areas, and lastly, the geospatial indexing framework S2 Geometry is used for final waypoint extraction to a node set. The edge set is constructed using a transition matrix that is used together with the final node set to construct the graph representation. Simulation results on the graph representation reveal the ability to construct routes with high resemblance to real-world routes. Further testing revealed high likeness between the most influential nodes in the graph representation and influential points-of-interest in the maritime shipping structure. In turn, the maritime shipping network graph representation is a tool for analysing the maritime shipping structure
On-line Capacitive Moisture Measurement of Iron Ore Concentrate
No full textAccurate moisture determination of iron ore concentrate, also referred to as ore concentrate, is important to the production of iron ore pellets. Existing methods have long response times, sampling variability and/or require manual work. Capacitive methods for moisture determination show promising signs of solving several of these problems.
To determine the feasibility of constructing an on-line measurement sensor utilising capacitive methods, a small-scale prototype consisting of a rotary conveyor dish, a capacitive sensor and measurement electronics was constructed. The sensor consists of two pairs of electrodes, each of which constitutes a capacitor with the surrounding material as dielectric. By placing the sensor below the rotational dish, allowing the measured iron ore concentrate to compose most of the dielectric medium, its permittivity, which will vary with its moisture content, can be measured as a change in capacitance.
Testing was performed to determine the effects of varying frequency, mass and speed of the measured material. The results show that even though there seems to be a strong correlation between the measured capacitance and the moisture content, it is hard to draw any direct conclusions on the correlation due to high local variability in the material, leading to uneven sampling and poor verification tests. Further
tests on a larger scale are suggested to remedy these problems
A channeled spectro-polarimeter for ground based atmospheric monitoring
No full textCharacterization of particle content in the atmosphere can be of both public health- and scientific
interest. One way of characterizing the particle content, without the need of having the Sun behind
the target, is by analyzing the polarization of the light incident from the direction of interest. This
project has entailed the assembly and testing of a polarimeter capable of detecting the presence of
varying particle content in the atmosphere, with high wavelength resolution. A detailed account
of this process is described in this document, including some theoretical background to facilitate
interpretation of the results. The principle of operation is similar to some existing instruments
but adapted for practical inclusion into the volcanic monitoring network NOVAC, or other ground
based enterprises such as monitoring of pollution in urbanized areas. Some work remains to scope
the capacity of the instrument, but the basic capability has been verified
Riemannhypotesen och Elliptiska Kurvor
No full textArbetet är en kort utläggning om Riemannhypotesen för elliptiska kurvor över ändliga
kroppar. Texten öppnar med en introduktion till affina och projektiva varieteter inom algebraisk geometri, för att sedan avgränsa och specialisera teorin till kurvor. Huvuddelen av texten
behandlar elliptiska kurvor och deras grupplag. Ett särskilt fokus läggs på morfier som bevarar
grupplagen och verktyg som används för att studera dessa, bland annat invarianta differentialer. Vi avgränsar sedan teorin till elliptiska kurvor över ändliga kroppar, samt den så kallade
Frobeniusendomorfin, som är central inom studien av rationella punkter. Avslutningsvis introducerar vi Tate-modulen och Weils em-parning, för att slutligen kombinera våra resultat och
bevisa nämnda Riemannhypotesen
En studie om vindassisterad framdrivning: Vindassisterad framdrivnings potential och hur svenska rederier ställer sig till tekniken
No full textVindassisterad framdrivning är en gammal teknik som har fått liv på nytt på grund av stigande bränslepriser och ett behov av att ställa om till förnybara energikällor. WAPS, Wind Assisted Propulsion System, har under de senaste åren börjat installeras ombord på handels- och passagerarfartyg i större omfattning, även om det stora genombrottet för tekniken ännu inte skett.
Syftet med detta arbete var att undersöka teknikens potential och funktion samt hur svenska rederier ser på och eventuellt förbereder sig för vindassisterad framdrivning. För att besvara arbetets frågeställningar har intervjuer samt litteraturstudier genomförts. De rederier som intervjuats har sina fartyg i drift främst i norra Europa, de flesta inom samma typ av sjöfart, men inte alla.
Data och forskning pekar på att WAPS kan minska fartygs bunkerförbrukning med 60% eller mer i framtiden under de rätta förhållandena, och att många fartyg idag kan spara runt 10–20% bunker med tekniken. Det finns dock stora variationer, och den vindassisterande framdrivningen kommer vara olika effektivt beroende på rutt och fartygsdesign.
Hos de svenska rederierna som blivit intervjuade finns positivitet, skepsis och engagemang kring vindassisterad framdrivning. Rederierna ser att det finns en möjlighet att minska bunkerkostnader och spara pengar genom WAPS-tekniken. Samtidigt så finns det en tveksamhet hos dem, som kan kopplas till en brist på verkliga framgångsrika exempel, och tekniska frågetecken kring bland annat installation och effektivitet. WAPS kommer att under de kommande åren installeras ombord flera fartyg, och resultaten från dessa fartyg kan accelerera eller fördröja den vindassisterade framdrivningens implementation.
Arbetet har fokuserat på bränslebesparingar och rederiernas syn på vindassisterad framdrivning ur ett tekniskt och ekonomiskt perspektiv. För att inte göra arbetet för stort, har avgränsningar gjorts på fartygens maskineri, propeller och roder samt rederiernas syn på teknikens framtid
Problem Solving in Thinking Classrooms Using Vertical Surfaces
No full textThis phenomenographic study explores how structured problem-solving activities, inspired by
the Thinking Classroom model and conducted on vertical surfaces, influence students'
learning experiences in upper secondary mathematics education. In recent years, interest in
student-centered and collaborative approaches to mathematics teaching has grown, aiming to
promote deeper understanding and engagement.
Semi-structured interviews with two teachers and six students, and an analysis of students'
written exam responses, were conducted to examine variations in how participants perceive
the use of vertical surfaces and group-based tasks. The study focuses on students’
mathematical reasoning, collaborative interactions, and attitudes toward problem-solving. It
also investigates teachers’ experiences regarding the pedagogical benefits and challenges of
implementing these methods.
The findings highlight key themes such as increased engagement, improved metacognitive
awareness, and enhanced collaboration. The results contribute to understanding how physical
learning environments and structured problem-solving approaches can support critical
thinking and mathematical development
Multi-Objective Optimization Under the Hood: Engine Calibration via Metaheuristics and Probabilistic Methods
No full textThe automotive industry faces the complex task of optimizing engine performance across diverse and often competing metrics, including fuel consumption and emissions. To effectively address this challenge and manage the necessary trade-offs, accurate engine calibration is essential. This thesis investigates the application of optimization methods, specifically Genetic Algorithms (GA) and Bayesian Optimization (BO), as a promising solution for engine calibration. Single-objective optimization targets the best solution for one goal, while multi-objective optimization balances trade-offs between conflicting goals to approximate the Pareto front, the set of optimal solutions where no objective can be improved without worsening another. This work explores both single-objective and multi-objective optimization implementations for GA and BO. In addition, a hybrid approach combining BO followed by GA is proposed for multi-objective optimization. The methods were evaluated in an experimental study. In the single-objective case, both GA and BO outperformed established internal benchmark values (provided by Volvo). For multi-objective optimization, GA, BO, and the hybrid method also achieved superior results. Across both single-objective and multi-objective problems, BO consistently delivered the best performance. These findings demonstrate that GA, BO, and the hybrid approach are viable strategies for engine calibration and provide a strong foundation for the development of more specialized calibration methods
Utveckling av ett Process Design Kit för supraledande kvantprocessorer
No full textI denna kandidatuppsats beskrivs vidareutvecklingen av ett Process Design Kit
(PDK) för supraledande kvantprocessorer, med målet att automatisera och effektivisera
designfasen av kvantchip. Processen bygger på utveckling av parametriska
celler i Python, designregelverifiering i Ruby och dokumentation av hela PDK:t.
Utvecklingen genomförs iterativt genom bearbetning av ärenden på GitLab. Versionshantering
sker via Git och lagras på GitLab.
Arbetet har delvis bestått av utvecklingen av parametriska celler i Python integrerat
med KLayout, där stöd för både absoluta och relativa koordinater för koplanära vågledare
samt interaktiva handtag för ”lumpade kondensatorer” har implementerats.
Därtill har en parametriserad teststruktur för Josephson-övergångar införts vilken
automatiserar mätprocesser och ersätter tidigare manuella rutiner. För att garantera
att vissa designregler uppfylls implementeras DRC-skript i Ruby som kontrollerar
överlapp, riktning och längd hos Josephson-övergångar samt verifierar galvaniska
kontakter. Slutligen införs generella förbättringar i PDK:t, inklusive automatisk versionshantering,
dynamisk steglängdsberäkning, autorun-skript för versionskoll för
KLayout och PDK:t, möjlighet att omladda PCell-moduler utan omstart av KLayout
och förberedelser för att släppa PDK:t som öppen källkod.
Genom dessa åtgärder har automationen och tillförlitligheten i PDK:t ökat, vilket
frigör tid för fortsatt optimering och utökning av verktygets funktionalitet. Vidare
rekommenderas en utvidgning med fler PCeller och fördjupade designregler för att
ytterligare förbättra både kapacitet och kvalitet