Studentarbeten // Student Theses

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3D finite difference time domain simulations and analysis of thrombolytic treatment for microwave measurements of stroke patients
(2014) Stålnacke, Antti; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
3D modelling of facial skin surface for 3D printing
(2017) Ekberg, Emma; Chalmers tekniska högskola / Institutionen för elektroteknik; Chalmers University of Technology / Department of Electrical Engineering
A concept study on tablet-based decision support system applied in ambulance and palliative care
(2013) Rampou, Maria; Sjöström, Daniel; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
A Parametric Study of Shoulder Belt Interactions with the PIPER Scalable Child Human Body Model in Frontal and Frontal Offset Impacts
(2018) Berntsson, Josefine; Chalmers tekniska högskola / Institutionen för mekanik och maritima vetenskaper; Chalmers University of Technology / Department of Mechanics and Maritime Sciences
Motor Vehicle Crashes (MVC) are among the leading causes of deaths for children globally. Complementary to the fatality risk, traffic road accidents are responsible for an even larger number of severe pediatric injuries which can lead to permanent impairment. Actions towards reducing or preferably eliminating this problem are to improve the design, accessibility and regulations of child restraint systems as well as implementation of these in actual passenger vehicles. Computer Aided Engineering (CAE) has become an integrated part of the contemporary automotive industry, providing the opportunity to perform crash tests using a simulation platform as a complement to physical crash tests. Finite Element Human Body Models have the potential to become a powerful tool in the virtual assessment of injury tolerances, kinematic behavior and interaction with vehicle interior design. Although substantial efforts have been contributed to the development of male HBM:s, in particular in the 50th percentile size interval, child size models are receiving less attention. Hence, the Position and Personalize Advanced Human Body Models for Injury Prediction (PIPER) project aimed to provide an open source child HBM, scalable within the range of 1.5-6 years old as well as different percentiles within each age group. In addition a scaling and positioning tool, PIPER Framework, has been released to facilitate personizalisation of FE HBM:s. This Master's Thesis project has evaluated the sensitivity of the PIPER scalable child model by exposing the PIPER baseline model (6 year old, 50th percentile) to three different shoulder belt angles, achieved by altering the D-ring position in an LS-DYNA environment. These belt routing setups have been applied to three different cases which included a belt-positioning booster, a high-back booster and a rear seat only during frontal and frontal offset impact. Kinematic behaviour of the child HBM and the occurrence of undesirable belt performance such as sliding of the shoulder resulting in increased roll-out risk or neck-loading, has been the main evaluating feature. Head accelerations, de ection of sternum and global head injury criteria (HIC) have been estimated and additionally used for comparison between the different parameters. Conclusions were made that the PIPER scalable child model was able to capture different undesired belt interaction behaviours such as roll-out and submarining, although further evaluations are necessary. A visual comparison with data retrieved during the literature review supported the exible kinematic trajectories of the PIPER scalable child HBM when exposed to the high-severity crash pulses of the parametric study. In terms of injury criteria, the PIPER scalable child HBM appeared to overestimate HIC15 values, hence additional research concerning biofidelic injury thresholds for children is necessary.
A pilot study on developing an artificial head for bone conduction devices testing purposes
(2021) Murali Dharan, Ashwin Kumaar; Chalmers tekniska högskola / Institutionen för elektroteknik; Reinfeldt, Sabine
A stand-alone test device for Bone Conduction Implant (BCI)
(2014) Ghoncheh, Mohammad; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
A Step Toward Personalized Cancer Treatment Simultaneous Detection of Multiple Types of Chemotherapyinduced DNA Damage Using Single Molecule Imaging
(2022) Foss, Ebba; Chalmers tekniska högskola / Institutionen för biologi och bioteknik; Chalmers University of Technology / Department of Biology and Biological Engineering; Westerlund, Fredrik; Akwasi Aning, Obed
Chemotherapy is commonly used to treat cancer today, either alone or more commonly as part of combination therapy. Response to a certain chemotherapeutic agent is highly individual, both in terms of treatment efficacy and the extent to which healthy cells are affected. For several drugs, induced DNA damage provides the main cytotoxic effect, and a method for evaluating this damage could therefore prove a powerful tool in treatment planning. In this thesis, a single molecule imaging approach is used to assess chemotherapy-induced DNA damage, allowing visualisation of damage sites on individual DNA strands. While previous studies have focused on one damage type, or collective damage without distinction between types, a novel modification to pre-existing techniques that allows for this distinction has recently been demonstrated. In this thesis, the alkylating agent temozolomide was used to illustrate how different damage types can be distinguished with a single molecule imaging approach. This is done using repair enzymes associated with different DNA repair pathways. The repair enzymes sequentially incorporate spectrally distinct fluorescent nucleotides at the damage site which are then visualized as fluorescent spots of two different colours on individual DNA molecules. This distinction could be shown with high repeatability in terms of colour ratio. While both enzymes used separately clearly repaired the treated DNA, there appeared to be an overlap when applying them sequentially. This could suggest a problem with enzyme specificity. Further exploration of this issue is needed to verify the feasibility of single molecule imaging for the purpose of simultaneous detection of chemotherapy-induced DNA damage types.
A study of sitting posture and belt position in a travelling car: How do passengers sit in a travelling car?
(2019) Hansson, Annika; Lysén, Emma Nilsson; Chalmers tekniska högskola / Institutionen för mekanik och maritima vetenskaper; Chalmers University of Technology / Department of Mechanics and Maritime Sciences
To improve the future design of restraint systems, it is important to know how passengers’ sitting postures change over time and how the passengers interact with the restraint systems. This master thesis at Chalmers University of Technology, focuses on pelvis rotation, slouching and belt position while travelling in a front seat of a car on regular roads. The information was collected during normal drive in the passenger seat of a regular car, while the volunteers perform activities such as; resting, e-socializing and conversing. Twenty volunteers, ten male and ten female, participated in the study. Volunteers were seated in the front row passenger seat, because this sitting posture is probably similar to how passengers will sit in future autonomous cars. The inertial motion measurement system MTw Awinda from Xsens, in total eight sensors, were used in the study. They were placed on the volunteer’s sacrum, sternum, C7, T3, L5, forehead and car. The data from the sacrum sensor, that corresponds with pelvis rotation are mainly presented and discussed in this report. In addition, a surface pressure sensing array (Tekscan mat) was placed on the car seat cushion. The data from selected volunteers was analyzed with the TEMA to determine degree of slouching. Photo analysis was carried out to assess belt positions before and after the test. Additionally, the rotation of pelvis and sternum when changing seat back angle in intervals of 5° between 23° and 48° were also investigated. The results show that pelvis rearward rotation increases by average 10° when riding in the car for about 45 minutes. Comparing the activities, the volunteers had similar average pelvis rotation. Slouching could be measured only for three volunteers out of 20 and it seemed to increase on average 3 cm during the ride. The belt position of initial and final sitting posture indicates that the diagonal belt moved less than the lap belt. To investigate the dynamic belt position, future video analysis is needed. Increasing seat back angle appeared to have a correlation with increasing sacrum and sternum pitch.
Accurate segmentation of brain MR images
(2010) Porras Péres, Antonio Reyes; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
AI-guided detection of antibiotic-resistantbacteria using resistance genes
(2024) Aerts, Erik; Chalmers tekniska högskola / Institutionen för matematiska vetenskaper; Kristiansson, Erik; Kristiansson, Erik; Johnning, Anna
Antibiotic resistance is threatening advancements made in modern medicine. Understanding the genomics behind multi-resistant profiles can assist in planning the correct treatment which can lower the abundance of antibiotic usage and hamper the vicious resistance cycle. Transformer-based AI models have shown state-of-the-art performance in understanding complex patterns in data. The thesis aimed to create a framework on how to implement transformers to predict bacterial resistance profiles by training on genomic data. The framework consisted of a transformer-based encoder and parallel classification networks for predicting antibiotic susceptibility. Each model trained on antibiotic resistance genes (ARGs) from Escherichia coli where a subset of isolates had recorded resistance profiles. The results showed that having a high complexity in the encoder is key for the model to accurately predict resistance to antibiotics where the occurrence of resistance is rare. This is relevant for any clinical setting, as models with less than 12 encoder blocks could not find these resistance profiles. The framework benefited from pretraining on unlabeled genomic data as performance generally increased. However, the type of masked language model pre-training which benefited the system more was situational and no conclusion was drawn. Finally, the thesis also found features in the data on which the models were basing decisions off on. The number of ARGs of an isolate was deemed the most influential feature in the data which relates to how much information the transformer can process. Following, relations between ARGs gyrA-D87N / parC-S80I and aph(3”)-Ib / aph(6’)-Id were shown to be an important decision basis for the models. Likewise, two point mutations of the pmrB gene also stood out as important ARGs in the decision-making processes for the models. The reasons why these ARGs are weighted highly by the models are currently unknown but are of interest to be studied further for a better understanding of underlying factors to multi-resistance.
An advanced 3D eye state filtering and classification algorithm based on physiological constraints of the human eye
(2016) Borre, Rickard; Nilsson Rabbaa, Marcel; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
An evaluation of human pose estimation using a deep convolutional neural network
(2017) Abelsson Runing, Sven; Chalmers tekniska högskola / Institutionen för elektroteknik; Chalmers University of Technology / Department of Electrical Engineering
An investigation of two different skin marker models for 3D gait analysis of the trunk
(2018) Sundström, Maria; Chalmers tekniska högskola / Institutionen för elektroteknik; Chalmers University of Technology / Department of Electrical Engineering
An IT-solution for clinical evaluation of an on-scene injury severity prediction algorithm intended for road crash victims
(2017) Olaetxea Azkarate-Askatsua, Ion; Chalmers tekniska högskola / Institutionen för elektroteknik; Chalmers University of Technology / Department of Electrical Engineering
Analysis on brain MR images by deep learning methods
(2018) Qu, Qixun; Chalmers tekniska högskola / Institutionen för elektroteknik; Chalmers University of Technology / Department of Electrical Engineering
Application development on compact UWB radar systems
(2014) Jian, Qiuchi; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
Application of hyperthermia for localized drug release from thermosensitive liposomes
(2010) Bhuiyan, Didarul; Chalmers tekniska högskola / Institutionen för signaler och system; Chalmers University of Technology / Department of Signals and Systems
Applications of microwaves in pharmaceutical processes - Development of a monitor for fluid bed- & continuous flow processes, an electroporation protocol, and a device for characterization of chemical samples
(2024) Nilsson, Robin; Chalmers tekniska högskola / Institutionen för elektroteknik; Dobsicek Trefna, Hana
Artificial intelligence for diagnosing knee ligament injuries
(2022) Nilsson, Alice; Söderholm, Linn; Chalmers tekniska högskola / Institutionen för elektroteknik; Kahl, Fredrik
Assembly and disassembly of the influenza C matrix protein layer on a lipid membrane
(2016) Eklund, Birger; Chalmers tekniska högskola / Institutionen för fysik (Chalmers); Chalmers University of Technology / Department of Physics (Chalmers)
Insight into the inner workings of viruses is an important piece of knowledge in humanity’s expanding collection of knowledge which can potentially be used to treat or prevent diseases. Influenza C is known to cause an infection with cold-like symptoms with possible complications in young children. The virus is a lipid-enveloped RNA virus in the Orthomyxoviridae family and incorporates 9 proteins. One of these is matrix protein 1 (M1C) which is found on the inside of the lipid-envelope of the virion. Influenza C in general and M1C in particular have not been extensively studied. However, influenza A and it’s matrix protein 1 have been studied to a great extent. In this thesis the binding and release of M1C on supported lipid bilayers (SLB) in various environments have been investigated. The SLB is a basic model of the lipid envelope of the influenza virions which is also suitable for the two surfacebased techniques used in this work. The two main environmental factors that were varied were the salinity and pH of the surrounding solution. The protein-protein and protein-bilayer binding behaviours were the two main interactions examined. In the Quartz Crystal Microbalance with Dissipation monitoring (QCM-D) the amount of M1C bound to an SLB was measured. Information on the adlayer’s viscoelastic properties was also obtained. With this technique it was revealed that the binding of the protein is highly dependent on electrostatic charges. In the microscope, fluorescence and Surface Enhanced Ellipsometric Contrast (SEEC) microscopy was used to observe the spatial arrangement of the M1C on the SLB. The SEEC microscopy was used to observe aggregations of M1C on the SLB. A fraction of the negatively charged lipids in the SLB were tagged with the fluorescent dye NBD and the clustering of these was observed with fluorescence microscopy. This combined with the SEEC observations gave the conclusion that the proteins aggregate on the SLB and recruit negatively charged lipids. This work found that the main binding strategy for M1C is is to utilise electrostatic forces. This is important because this binding is used both in the forming of the virions and for maintaining the structural integrity of the virion. It was also found that endosomal pH leads to some dissociation of M1C from the lipid bilayer. This is important since the dissolution of the virion’s matrix protein layer in the endosome has been shown to be vital for infection in influenza A.

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