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Stochastically Modelling Road Topography Identifying Road Topography: Characteristics and Stochastically Modelling it for Simulations
No full textRoad topography is the 2-dimensional elevation profile of a road and is a critical
factor in evaluating vehicle performance and energy consumption in the transport
sector. Currently the most used method is to model existing roads. This method
requires that a suitable real representative road exists or needs to be constructed in
expensive testing tracks. It also runs into the problem of being constrained to one
road and can’t capture the larger characteristics of an area.
This study aims to find alternatives to this method by modeling road topography
stochastically to create an infinite number of roads with varying characteristics. To
achieve this, it investigates real world road data and develops various stochastic
modeling approaches to generate synthetic road profiles that capture the key
topographical characteristics observed in actual roads. The models that were
examined were AutoRegressive(1), ARMA(1,5) and Markov chain model. The
models were designed to model the slope of the road to capture the characteristics
of a set of input roads. The generated models are validated against real world
data using multiple comparison metrics, to assess their ability to capture real-world
characteristics. This is to evaluate the potential for simulation applications.
To identify which characteristics are essential for road topography modeling, a
qualitative study was performed, where experts within vehicle engineering disciplines
were interviewed
Dwellbeing; residential architecture for mental health
No full textIn this stressful world, one might look to
architecture for answers on better mental
health. Research shows that we spend about
90% of our time indoors and almost 19
hours a day in our homes. The new building
regulations from Boverket are a big threat
to the residential qualities we have taken for
granted. Along with the strained Swedish
healthcare system and the fact that an
increased amount of people are suffering
from mental illness - this constituted the
thesis’ background. The aim was to explore
how architects can enhance building qualities
related to residential architecture for the sake
of people’s mental health, emphasizing on
stress-regulation. The research questions
were 1) What architectural concepts can
be identified in residential architecture
that promote good mental health through
stress regulation, based on relevant
theories? 2) How can these concepts be
sustainably applied in a housing project on
the site of Tuvesvik? 2B) In order to illustrate
generalizability, how can the same concepts
be used in a housing project in Högsbo
- an urban site? The theories used were
interdisciplinary; the residential aspect of
enriched environments, the importance
of the outdoors, the perceived sensory
dimensions along with support of other
relevant research in residential qualities.
Methods used were; a literature overview
highlighting important research, an extensive
case study, and research through design.
Two design projects were carried out - a main
one in a rural context (Tuvesvik) and another
one in an urban context (Högsbo). Results
generated six design concepts for residential
architecture for mental health; directional
diversity, transitions, zones of social and
private, context sensitivity, individuality, and
control and safety. Two research-informed
design proposals were conducted to embody
previous mentioned design concepts. On
Tuvesvik, this resulted in eight semi-detached
houses and in Högsbo this meant terraced
housing (16 dwellings in each). The thesis
showed how design concepts for mental
health in residential architecture can be
used also in future projects, due to their
general and applicable nature. The overall
implications are relevant not only because
they address the societal problems with
mental illness - but also because it amplifies
residential qualities in the light of recent
threats. However, the findings must be further
supported to be fully generalizable
Effects of fault zones and hydrothermal alteration on the physical properties of crystalline rocks
No full textLow frequency vibrational behaviour in concrete structures; exploring structural reverberation time and distance based attenuation trends across building floors
No full textThis thesis investigates low-frequency structure-borne sound propagation in concrete
floor slabs across multiple floors of a building. The study aims to assess whether
a relationship exists between reverberation time, distance-dependent vibration level
decay, and group velocity. Both in-situ measurements and numerical simulations using
Comsol Multiphysics were conducted to analyse structural vibrational behaviour
and estimate parameters such as propagation velocity, reverberation time, and
attenuation per distance (dB/m) in the 50–160 Hz third-octave band range.
The structural impulse responses were post-processed through backward integration
and time-delay estimation techniques, allowing for comparison between simulated
and real building conditions. Five analytical propagation models combining geometrical
spreading and damping were fitted to the data using Matlab functions.
The results from both simulations and measurements suggest that no consistent or
global link could be established for the reverberation time (T60), and therefore no
clear proportional relationship was found between T60 and the vibrational level decay
over distance (La). However, some tendencies toward a proportional relationship
between La per distance and the effective group velocity ceff were observed. Notably,
the velocity trends diverged between simulation and measurement, indicating potential
differences in wave type dominance over distance for the measured data and
the simulated results.
The findings reveal the limitations of modeling large, complex structures due to
computational constraints and emphasise the importance of local geometry and
boundary conditions in structural acoustic behaviour. Although a complete predictive
model could not be established, this work provides a framework for assessing
energy-based decay behaviour in solid structures. It proposes directions for future
development of building-scale low-frequency vibration prediction models
Multimodal Approach to Enhance the Navigation System of the Shared E-scooter
No full textShared electric scooters are an important component of sustainable urban transportation, yet current navigation systems rely heavily on smartphone screens, introducing safety risks and usability limitations. This thesis addresses these issues by
designing and evaluating a multimodal navigation interface that integrates ground projected augmented reality (AR) with auditory instructions and a visual user interface display (UI). A user-centered design process guided the research. It started with qualitative methods (interviews, on-site observations) to identify user pain points and contextual needs, followed by quantitative analysis to deepen understanding of common issues and riding behaviors. Iterative design yielded concept sketches and wireframes, then a Unity-built VR prototype. Final usability testing evaluated task performance and cognitive load across interaction modalities, using cognitive efficiency as the key metric. A controlled evaluation of the design prototype with 30 participants compared six configurations (single-modality, e.g., UI-only, to multimodal combinations). Results showed the AR + audio interaction + UI display configuration achieved the highest cognitive efficiency (E=0.84 ±1.20) and lowest mental workload (NASA-TLX = 33.35 ±16.81), with statistically significant improvements over all other configurations, while the UI-only system had the lowest efficiency (E=1.46 ±1.08) and highest cognitive load (statistical tests confirmed differences in performance, effort, and perceived frustration). Key findings from user testing included the following: (1) Channel redundancy may reduce cognitive efficiency, as users tend to rely primarily on one modality (e.g., augmented reality [AR] significantly outperformed user interface (UI) + AR, efficiency: p = .001); (2) Complementary coordination of modalities yields significant improvements (e.g., UI + AR + audio significantly outperformed UI + AR [efficiency: p = .001] and UI + audio [efficiency: p = .002]). These findings highlight the potential of multimodal navigation systems: especially those that integrate projected AR - for improving safety, usability, and rider satisfaction in shared micromobility systems. However, this study has limitations: user testing was primarily conducted in a static, stable VR setup, while real-world road environments are far more complex, which would impose greater cognitive load on users
Built in happiness; crafting community spaces that embrace nature
No full textShift of population from rural to urban regions, is happening globally at a rapid pace. It has resulted in technological
and infrastructural development, thereby producing more economic opportunities and improving the way of life.
Conversely, it hurts the physical and mental well-being of individual. Due to the fast pace of the current world,
people are becoming more stressed and unaware of their surroundings. Social centers can become hubs where an
individual can unwind and socialize with others. However, due to limited space, developers prioritize giving
infrastructural and economic needs, and social hubs are not given a thought. This thesis investigates how one can
transform underutilized spaces into a sustainable community hub, promoting physical and mental well-being, and
enhancing social skills in the community.
Biskopsgården, a residential district in Gothenburg, is taken as a case example, and the prospect of multifunctional
outdoor spaces in the area is explored. A thorough area evaluation, supplemented with interviews with local
authorities, a study of available literature resources, and case studies, has indicated a lack of gathering space for the
local community.
The proposed solutions include interactive fitness spaces, open kitchen, open gathering areas, and flexible
communal hubs. These interventions integrated with the theories of biophilic design elements such as natural
materials, lighting, and ventilation, to achieve a stronger connection between people and nature in the modern
world. The application of third place theory ensures that these spaces encourage spontaneous social interactions,
cultural exchange, and experiences as knowledge sharing, which strengthens urban inclusivity and social well-being.
The findings illustrate that intentional spatial design can reduce urban stress and improve air quality to create
restorative surroundings that help both individuals and communities
Utveckling samt evaluering av lokalisering och kooperativa styrsystem
No full textThis report covers a bachelor’s thesis at Chalmers University of Technology. The purpose
of this project was to further develop systems for localization and driving of autonomous
vehicles inside of a lab environment building upon previous projects. Improvements were
made in three distinct areas. The first being the indoor localization system, called
GulliView, which consists of four ceiling-mounted cameras using Apriltags as calibration
and detection of vehicles. GulliView was improved by implementing an efficient undistortion
algorithm to counteract the camera’s distortion while maintaining accuracy. As
well as creating a unified global coordination system using the world position in meters.
Secondly, additional general maneuvers were implemented to autonomous robots using
GulliView for positioning. The added maneuvers handle common traffic situations such
as intersections, highway merging and roundabouts. Lastly, an advancement was made on
implementing Sensor Fusion between a vehicle, which has a previously developed internal
positioning system, and GulliView. The vehicle integrates the internal position and the
external position given from GulliView.
GulliView attained a median delay decrease of 86%, going from 102 ms to 14.0 ms in time
per execution cycle. Meanwhile, the median frequency increased from 10.5 Hz to 16.6 Hz.
Improvements on GulliView’s positioning accuracy were also observed, going from discrepancies
of 8-18% to 1-2%. For the autonomous vehicles, the added maneuvers added only
an average of 24.32% increased waiting time in traffic scenarios while maintaing safety.
Finally, the fusion of internal and external values resulted in a positioning discrepancy of
5%. These results prove promising and may greatly help further development of all three
systems in future projects
Utveckling av klimatpolitisk beräkningsteknik med sekventiella beslutsproblem under osäkra förhållanden
No full textKlimatkrisen medför komplexa beslutsutmaningar som sträcker sig över lång tid och präglas av stor osäkerhet. I denna kandidatuppsats undersöks en metod för sekventiellt beslutsfattande inom klimatpolitik, där beslut tas iterativt över tid under osäkra förhållanden.
Arbetet bygger på en befintlig modell av Botta et al. [1] som kvantifierar vilka klimatbeslut som spelar störst roll under osäkerhet. Implementeringen av modellen var ursprungligen skriven i det funktionella programmeringsspråket Idris, men för att öka tillgängligheten har modellen översatts till de mer etablerade språken Haskell och Python. Översättningen möjliggjorde även en validering av modellens korrekthet och prestanda. Denna rapport redogör för den teoretiska grunden för sekventiellt beslutsfattande och
klimatpolicy. Vidare beskrivs två klimatmodeller, både den skapad av Botta et al. [1] som översattes och en vidareutvecklad modell, samt metodiken för kodöversättning. Resultaten visar att de översatta modellerna producerar resultat som är identiska med originalimplementationens utfall och att prestandan är bättre än den ursprungliga implementationen.
Vidare diskuteras potentiella förbättringar av modellens effektivitet och användbarhet, såsom möjligheten att utöka modellen. Slutligen behandlas de samhälleliga implikationerna av klimatpolitiska beslut och det diskuteras kring hur förbättrade beslutsmodeller kan bidra till mer informativa och ansvarsfulla klimatstrategier
Making the right contract choice: A study of AB 04 and ABT 06 in office construction procurement in Gothenburg
No full textThe construction industry is one of the biggest sectors globally and face a
recurring problem in budget overruns, often linked to flaws in contract writing
and risk dividing between stakeholders. This thesis investigates the Swedish
standard agreements AB 04 and ABT 06 and how these differ, how these address
economic, social and qualitative risks and how the choice of contract form can
affect the risk of a project breaching its budget. The study focuses on the
construction of an office construction in Gothenburg and employs an abductive
research approach to develop theories and generalizations to help the
construction industry. The research is based on nine interviews with
experienced industry professionals and the development of a theoretical
framework. The findings of the research demonstrate that the the most
fundamental difference between the AB 04 and ABT 06 lies in the project
execution structures where AB 04 adopts a Design-bid-build (DBB) execution
and ABT 06 involves a Design-build (DB) execution. Furthermore, the results
display that the choice of contract form cannot be generalized for all office
building but rather emphasize the need to understand the nature of the project
and the clients’ internal resources for design and planning. Also, the findings
underscore the significant role of collaboration in ensuring project succes
The future heritage of artificial landscape; challenging the concept of aesthetics and exploring identity in the reinterpretation of industrial entities
No full textWith the contemporary world becoming more conscious
of the choices made concerning use of natural resources,
industrial areas are going through a shift of perception, and
their future is uncertain. As they are examined, a question is
posed whether they represent heritage, lives of the former
generations, or are simply parts of a rather regrettable past.
The purpose of this master thesis was to investigate the
potential shift in perception of post-industrial spaces and
prove that they should be considered as future heritage. It has
aimed to challenge the commonly accepted idea of aesthetics
and find appealing qualities in the artificial landscapes created
due to human activities. It concentrated on the reinterpretation
and readaptation of post-industrial structures and emphasized
the need for new nature in those areas. The project area
was located in the city center of Gothenburg, focusing on
Rosenlundsverket - a power plant located on the riverbank of
Göta Älv.
By conducting multiple site visits and collecting accessible
archival material, the site and its context were analyzed,
treating Rosenlundsverket and its surrounding landscape as
one entity. Utilizing the research by design method, volume
studies have been conducted, determining the most suitable
design option for the site. Reference projects were treated
as case studies, and design methods present in them were
transferred into the design. With the aid of transformation
theories, a new narrative was suggested for Rosenlundsverket.
The proposed reinterpretation of the building suggested
exploring it as a part of the public realm and reintegrating it
with nature. The thesis has also proposed new functions for
the existing building in the form of an art museum and a club,
with the contemporary additions complementing them with
art studios and an auditorium. The landscape design took
the form of a park situated around Rosenlundsverket and
proposed a new nature design language for the city.
The design proposal is represented in the form of drawings
and visualizations that emphasize the design concept and
contrast between old and new. The design proposes a
space that should be for all, making heritage tangible and
approachable while simultaneously enhancing the identity of
Rosenlundsverket and carrying it further into the future