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Sustainable Water Use at Volvo Cars Torslanda - An Assessment of Water Use and Potential Reduction Strategies at Volvo Cars Operations in Gothenburg
No full textThis thesis investigates water use and potential reduction strategies at Volvo Cars’
manufacturing site in Torslanda (VCT), Gothenburg. With increasing global water scarcity
and rising costs for municipal water, the automotive industry must identify opportunities for
more sustainable water management. In 2024, the total water withdrawal at VCT was 357
700 m³, with the paint shop accounting for approximately 79 % of this volume. Current water
use amounts to 1.32 m³/car for manufacturing operations and 2.81 m³/car when non manufacturing operations are included.
The aim of this study was to analyze existing water flows, characterize water quality and
evaluate strategies for water reuse and recycling. Laboratory work and process mapping were
combined with feasibility analysis using a Sustainability Benefit-Cost (SBC) model. Four
main actions were evaluated: (1) recycling effluent water to the demineralization process, (2)
recycling effluent water to surface treatment processes, (3) reusing wastewater collected from
condensate tanks to the demineralization process, and (4) reusing wastewater for processes in
TB4.
Results indicate that recycling 71 000 m³ of effluent water to the demineralization process
could reduce water withdrawal by 20 %, with a short payback time (<1 year) and a high water
benefit score (7.5). Reusing wastewater from a collection tank could save an additional 9 300
m³, further reducing water use and organic wastewater volume sent to the municipal
treatment plant, Gryaab. If all actions are implemented, total water use could decrease by 22
%, reaching 1.03 m³/car for manufacturing and 2.51 m³/car including all operations.
The findings highlight that both economic and environmental benefits can be achieved
through strategic water management and investment in water recycling and reuse. However,
the long-term success depends on ensuring water quality, addressing membrane degradation,
and validating cost assumptions
Design of a Complex Tethering System: A prototype of an expandable drone tethering system
No full textThe dissertation aims to explore a new approach to extend the mission length and
expand the flexibility of drone applications for indoor environments where a GPS or
GNSS signal is not available. The research addresses the need for enhanced power
management and coordinated control in multi-drone systems. A tethering system
is created as a prototype to enable simultaneous power distribution and dynamic
positioning. Experimental testing was conducted in a controlled lab environment
using a linked customized quadcopter and an indoor positioning system. The system
demonstrated a complex tethering system with longer durability, higher flexibility,
and higher modularity. The prototype provides a foundation for future deployment
in a variety of areas including persistent surveillance, emergency communication,
indoor manufacturing, and so on. Future work is expected to focus on improving
control accuracy and system stability
Stacking of 2D materials via self-assembly
No full textRemarkable physical and chemical properties of 2-dimensional transition metal carbide
and nitride are grabbed much attention among the nanomaterials researchers.
MXene, a new fascinating family of 2D transition metal carbides, nitrides, and
carbonitrides. MXene has recently acknowledged significant attention due to its
unique combination of properties such as large interlayer spacing, hydrophilic nature,
excellent thermal stability, and high electrical conductivity, which proposed to
be promising materials in many applications such as supercapacitor, solar cell, sensor,
battery, water purification, sensor and electronic devices. Intriguing property
value of Titanium carbide (MXene), convergence and adaptability of application in
next generation devices is developing thin film technology. From the produced MXene
nano sheets, using its nature of hydrophilic quality approached in self-assembly
mechanism. Bottom up strategy of liquid-liquid interfacial have been puzzling the
monolayers film formation based on different substrates. Here, interfacial tension in
between two immiscible solvents is responsible for self-assembly because of its spontaneous
ordering of 2D MXene in lateral structure. Flat surfaced substrate is used
to transfer the self-assembled monolayers, then the fabricated MXene on substrates
of surface morphology is examined in optical microscope, and Scanning electron microscope.
From the inspections, it is clear based on the collection sped and time
the size of the MXene can be varied in different size. In this regard, stacking the
low dimensional materials such as homogenous MXene, chemical vapor deposited
Graphene on copper substrate, and mixture of MXene-Graphene Oxide composite
were investigated in this project
Warehouse automation in the construction material and lumber industry A case study of the Swedish company Derome Bygg & Industri AB
No full textSuppliers of construction materials face an increasing demand for efficient logistics
operations, while the use of automation in their supply chains remains limited. A key
challenge lies in the bulky and heavy nature of construction materials, which complicates
handling and automation. This study investigates how Derome Bygg & Industri AB (DBI) can
improve their logistics through implementation of automation in picking, packing, and loading
operations.
A mixed-methods approach was employed, including interviews with DBI logistic managers
and operational staff, on-site observations, analysis of historical company sales data, and a
literature review focusing on warehouse design, automation, and Industry 4.0 technologies.
Empirical data was also collected from suppliers of automated equipment.
The study examines DBI’s current operations and develops a categorisation of product
groups suitable for automation. Several technological solutions were found suitable to DBI’s
context. The analysis indicates that wooden planks and sheet materials offer the
greatest potential for efficiency gains through automation. The findings provide practical
implications to support DBI’s future investment decisions and contribute to a broader
understanding of warehouse automation strategies in the construction material sector
Undervisningsmaterial i mekanik med 3D-skrivning
No full textSyftet med projektet har varit att utveckla undervisningsmaterial i mekanik för gymnasieskolan
med hjälp av 3D-skrivare. Dessa modeller har därefter tillgängliggjorts
genom STL-filer (Stereolithography) som kan laddas ner av lärare för att därefter
skrivas ut. Målet utformades till att utveckla tre olika uppställningar, en med trissor,
en för lutande plan och en för kaströrelse. Modellerna ska kunna möjliggöra
att elever får se, röra vid och experimentera med modeller som beskriver abstrakta
koncept inom fysik för att öka förståelsen och intresset.
Arbetet inleddes med en intervju med en universitetslärare från Chalmers som undervisar
inom mekanik och termodynamik för programmet tekniskt basår vilket
ska motsvara gymnasienivå. Detta kompletterades även med ett frågeformulär som
skickades ut till gymnasielärare. Förstudien visade att det fanns en efterfrågan av
fysiska modeller, med särskilt intresse för de tre utvalda områdena. Baserat på detta
togs tre modeller fram med hjälp av CAD-programvara (Computer-aided design)
och 3D-skrivarteknik, och skrevs ut i E-PLA (Environmentally friendly Polylactic
Acid), ett miljövänligt och lättillgängligt plastmaterial. För varje modell utvecklades
ett instruktionsblad med uppgifter och lösningsförslag. Designen har anpassats
för att modellerna både ska vara pedagogiska men även praktiskt hanterbara, till
exempel genom att de enkelt kan monteras, justeras och transporteras.
Resultatet visar att 3D-skrivna modeller har potential att bli ett värdefullt undervisningsredskap.
Projektet visar också på möjligheterna att producera undervisningsmaterial
som är anpassningsbara, kostnads- och tidseffektiva. För framtida arbeten
föreslås vidareutveckling av befintliga samt nya modeller och eventuell anpassning
för andra skolnivåer eller fysikaliska områden
Deep Learning-based Segmentation of Kidneys from MR Images
No full textAbstract
Chronic kidney disease (CKD) is a progressive condition affecting millions worldwide, and accurate assessment of kidney structure is essential for early diagnosis and monitoring disease progression. Magnetic Resonance Imaging (MRI) has emerged as a powerful, non-invasive technique for visualizing subtle structural and functional changes of the kidneys, providing insights into disease progression and severity. However, manual segmentation of MRI data is both time-consuming and prone to interand intra-observer variability, highlighting the need for automated methods. This thesis presents a deep learning-based approach for automated segmentation of the renal parenchyma, cortex, and medulla using multi-channel and multi-modal MRI data. A 2D ResUNet architecture was implemented with the Medical Open Network for AI (MONAI) framework and trained on a dataset of 37 MRI scans from CKD patients. Two approaches were evaluated: a multi-channel model utilizing T1- weighted Modified Look-Locker Inversion Recovery (T1-MOLLI) images at multiple inversion times, and a multi-modal model incorporating diffusion-weighted imaging (DWI) and T2*-weighted image data. While the multi-channel T1-MOLLI model demonstrated strong agreement with manual annotations, achieving Dice scores of 0.9089 for parenchyma and 0.8552 for cortex, the multi-modal approach underperformed due to spatial misalignment between input images and reference labels. The proposed segmentation pipeline also enabled reliable quantification of renal parenchyma and cortex volumes, and showed potential for quantifying tissue-specific
parametric values relevant to CKD monitoring. However, the reliability of these measurements were highly dependent of the models segmentation performance. Overall, the findings highlight the potential of using deep learning models’ with multichannel MRI input for improving kidney segmentation, serving as a tool to support clinical image analysis workflows and reduce manual effort
Chiral Effective Theory for Spin-1 Dark Matter- Nucleon Scattering
No full textThis thesis aims to investigate the elusive dark matter via formulation of its interaction
with normal matter. This approach is commonly known as direct detection
which is an active field of dark matter research, both theoretically and experimentally.
We treat the dark matter as a heavy complex vector field, corresponding to a
massive spin-1 particle, which weakly interacts with a nucleus. The thesis utilizes
effective field theory and chiral perturbation theory to create a general interaction
Lagrangian. Starting in a relativistic approach, quantum mechanical interaction operators
are found which in turn can be used to calculate scattering amplitudes. The
thesis assumes non-relativistic and heavy dark matter to perform a non-relativistic
reduction which aims to investigate what constraints and bounds created in the relativistic
regime that lives on in the non-relativistic limit. The results are compared
to previous work within the field which leads to a comprehensive analysis of the
situation
Bring back the water; a phenomenological adaptation of an old water plant into spa and café
No full textWe interact with architecture every day and experience it through our whole bodies. Hence,
the human body cannot be neglected in the design of buildings if we want humane cities.
In addition, there is a need for the construction sector to reduce its emissions of greenhouse
gases. One solution to this is adaptive reuse of existing buildings. Adaptive reuse is beneficial
in environmental, socio-cultural and financial aspects.
With this as a starting point, this master’s thesis aims to investigate how phenomenology and
atmospheres can be used in adaptive reuse and how cultural heritage could be preserved
during an adaptation. To do so, the thesis is based on two research questions:
How can a design focus on atmospheres and phenomenology form a spa facility in an
existing building?
How can the old water treatment on Visholmen be revitalized while preserving its cultural
heritage?
To be able to answer the research questions, knowledge about phenomenology,
atmospheres, and adaptive reuse was developed. Information about the topics was also
gained from three reference projects, Therme Vals, Andrum, and Neues Museum.
In the process a variety of methods were used and can be divided into three phases. In
the first phase knowledge about the site, existing building and new program were gained.
Knowledge from the first phase was then implemented in the second phase, which was
characterized by iterative design work. The project was then finalized during the third phase.
The project is an adaptation of an old water plant into a spa and café, located on a
peninsula in central Strängnäs. The existing building is made of brick and was built in early
1900s. The condition of the building varies and the main strategy for the adaptation was
to keep, restore or repair vital features from a cultural historical point of view and add new
materials and functions suitable for the new purpose. To make the adaptation into spa and
café successful, additional buildings were required
Fyllnadsgrad och transporteffektivitet: En analys av DHL Supply Chain och cross-docksamarbetet med Volvo
No full textSammanfattning
Detta examensarbete har som mål att analysera hur effektiviteten i lastbilstransporter
mellan cross-docken i Torslanda och Volvos produktionsanläggningar kan förbättras. Trots
det etablerade samarbetet mellan parterna och en klar struktur för in- och utflöden visar
transportdata att fyllnadsgraden i vissa fall är lägre än 60%. En sådan ineffektivitet leder
inte endast till högre kostnader utan bidrar även till en mer sårbar logistikstruktur.
Studien har genomförts som en kvalitativ fallstudie med inslag av kvantitativ dataanalys.
Datainsamlingen har genomförts med semistrukturerade intervjuer med nyckelpersoner hos
både DHL och Volvo, observationer på plats vid cross-docken samt analys av tillgänglig
transportstatistik. Teoretiska utgångspunkter har hämtats från logistikforskning med fokus
på fyllnadsgrad, optimering av transporter, delning av information samt digitalisering inom
försörjningskedjor.
Resultaten visar att flera olika faktorer kan påverka fyllnadsgraden negativt. En av de mest
framträdande orsakerna är en strukturell obalans mellan inkommande godsflöden från
leverantörer och det statiska avgångsschemat mot Volvo, vilket leder till en ojämn
belastning och svårigheter att planera. Vidare identifieras bristande informationsbyte mellan
DHL och Volvo, begränsad flexibilitet i avgångarna samt manuella och tidskrävande
arbetsmoment vid sortering och lastning som hinder för ökad effektivitet. Det framkommer
också att det inte finns några digitala verktyg som kan stödja optimerad lastplanering i
realtid.
För att öka fyllnadsgraden rekommenderas ett antal åtgärder. Dessa omfattar
introduktionen av mer flexibla avgångstider, förbättrad samordning och delning av
information mellan aktörerna, samt investeringar i digitala verktyg som möjliggör
visualisering av lastkapacitet och mer effektiv planering. Standardisering av palltyper
identifierades även som en värdeskapande insats.
Sammanfattningsvis visar studien att det finns flera tydliga möjligheter till förbättring för att
höja fyllnadsgraden i just-in-time-transporter mellan DHL och Volvo. Genom att kombinera
organisatoriska, tekniska och kommunikativa förändringar kan både ekonomiska och
hållbarhetsrelaterade vinster uppnås, samtidigt som transportflödet blir mer
motståndskraftigt och säkert för framtiden