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Identification and functional characterisation of putative amino acid transporters in Leishmania mexicana
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Exploring (pseudo-)layered transition metal chalcogenides as novel cathode materials for magnesium-based batteries
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Rights in the era of ‘green’ market expansion: articulating radical demands
Get PDFThe unfolding planetary crisis confronts us with unprecedented challenges. As climate change and biodiversity loss accelerate, environmental and social movements across the planet increasingly turn to human rights, to tackle the problems global policy largely fails to address. More and more, rights are not only invoked to press governments towards more ambitious climate action, but also against the injustices resulting from our responses to the planetary crisis. A central feature of global climate law and policy are market-based solutions. While proponents praise them as the most efficient way to reduce emissions, market mechanisms favour historical polluters and are geared towards upholding the capitalist political economy that has caused the crisis in the first place. While rights-based litigation seeks to confront the multiple injustices caused or exacerbated by ‘green’ markets, rights’ transformative force remains ambivalent. While human rights are often seen as a device of resistance against capitalism’s excesses, their orthodox understanding is firmly rooted in Western-liberal individualism, centred on the human, property owning subject. Consequently, critical scholars have called into question human rights’ emancipatory potential or even accused them of being complicit in neoliberal globalisation. Looking at recent case law on climate and just transition permits to retrieve a differential understanding of rights, that neither uncritically endorses, nor entirely dismisses them. Climate and just transition litigation suggest that human rights are best conceptualised as oscillating between two poles: As a-legal, radical demands, they confront and challenge the given order – as authoritatively mediated decisions in the field of law, they consolidate the given political-economic set up. Understanding rights this way helps to inform our thinking about how we best employ them strategically
Robotic teleoperation: a cross-cultural study of user experience and performance
Get PDFThis thesis explores the performance and user experience of robotic teleoperation systems, focusing on the impact of various factors such as control methods, robot types, and levels of immersion. Robotic teleoperation, which allows human operators to control robots directly by moving some part of their body, is a critical technology in fields ranging from industrial automation to medical robotics. However, the cognitive and physical demands placed on operators, especially non-experts, remain under-explored. This research addresses these gaps by developing a modular, plug-and-play framework for direct teleoperation and conducting extensive user studies across different hardware configurations and cultural contexts.
The core contributions of this thesis include a systematic comparison of simulation software for robotic arm manipulation using ROS2, the development of a novel teleoperation framework called TELESIM, and an investigation into the effects of immersion through a mixed reality system named IMMERTWIN. The systematic comparison, achieved through a benchmark of various ROS2-compatible simulation platforms evaluates their suitability for teleoperation tasks, resource utilization, and their potential to serve as digital twins. This evaluation provides critical insights into the strengths and limitations of current simulation tools in supporting real-time robotic operations. Using the insights gained from our evaluation, TELESIM, a modular and plug-and-play framework, was designed to enable seamless control of different robotic systems with minimal setup time. It leverages digital twin technology to offer real-time feedback and control, allowing operators to interact with the robot to execute tasks in the real world. This framework was tested across multiple robotic platforms (e.g., UR3, Baxter, UR5e), control methods (e.g., VR controllers) and countries (e.g., UK, Japan) offering a flexible solution for diverse teleoperation scenarios. Additionally, IMMERTWIN, a mixed reality system, was developed to explore how varying levels of immersion affect operator performance and cognitive load. By integrating real-world data into virtual environments, IMMERTWIN enhances user interaction with robotic systems, providing a more intuitive and immersive teleoperation experience. The research also delves into external factors such as user expertise and trust in robots, examining how these elements influence teleoperation performance across different cultural contexts.
Key findings demonstrate that robot type, controller configuration, and immersion level significantly affect task performance and operator workload. For instance, the study revealed that different robots such as the Universal Robot 3 or Baxter, exhibit varying levels of precision and ease of control, which directly impacts task completion times and error rates. Quantitative results showed the Red Design (Baxter with VR controllers) achieved a 77.42% cube placement rate compared to only 46.29% for the Blue Design (UR3 with SenseGlove). Task completion rates also varied dramatically, with 85% of participants using VR controllers successfully completing tower-building tasks within the allocated time, compared to only 46% of those using SenseGlove controllers. Immersive systems like IMMERTWIN, which integrate real-world data into virtual environments, were shown to reduce cognitive load by providing more natural interaction cues and better situational awareness. NASA-TLX assessments demonstrated that IMMERTWIN reduced mental demand scores by 23% compared to non-immersive systems. Additionally, the research highlights the importance of external factors such as user expertise and trust in robots. Non-expert users, who participated in a large-scale international study conducted in both the UK and Japan (n=74), reported varying levels of comfort and trust depending on their cultural background and prior experience with robotic systems. The study found that the Japanese participants generally exhibited higher levels of trust toward robots compared to their UK counterparts, with Japanese participants scoring 41.94 on the Negative Attitude Towards Robot Scale compared to 49.43 for UK participants, representing a statistically significant difference of 15%. The Yellow Design (UR5e with VR controllers) produced the lowest NASA-TLX mental demand scores (8.94 out of 21), while the Blue Design resulted in the highest physical demand (11.65) and frustration levels (10.76). Overall, the thesis provides valuable insights into optimizing teleoperation systems for non-expert users by balancing technological complexity with human-centric design principles, ultimately paving the way for more accessible and efficient human-robot collaboration.
In reference to IEEE copyrighted material which is used with permission in this thesis, the IEEE does not endorse any of University of Glasgow’s products or services. Internal or personal use of this material is permitted. If interested in reprinting/republishing IEEE copyrighted material for advertising or promotional purposes or for creating new collective works for resale or redistribution, please go to http://www.ieee.org/publications_standards/publications/rights/rights_-link.html to learn how to obtain a License from RightsLink
Overcoming critical interface design challenges for Automated Vehicle-cyclist interaction
Get PDFCyclists are vulnerable road users who must share the road with motorised vehicles [66]. They rely on social interactions with drivers to resolve space-sharing conflicts safely and without ambiguity [82]. The advent of automated vehicles (AVs) will remove these social interactions, compromising the safety of cyclists [97]. AV-cyclist interfaces are promising solutions; these devices facilitate clear communication by allowing AVs to communicate explicit signals [37]. For example, displaying the AV’s intentions via LED lights on the AV or augmented reality glasses worn by cyclists [67]. However, AV-cyclist interfaces must overcome four key design challenges to be usable on real roads: acceptability to match the needs and requirements of cyclists [41, 49]; versatility to operate across various traffic scenarios, such as intersections or roundabouts [12]; cultural inclusivity between countries with different cultural norms and traffic infrastructure [108], and scalablity for many-to-many AV-cyclist interaction [123].
This thesis describes 10 studies conducted to overcome these challenges. These established requirements for AV-cyclist interfaces through observations and eye-tracking studies conducted in real traffic. The requirements were used to design interfaces through participatory design and test them in outdoor and simulator-based user studies. Findings for acceptability showed that interfaces should be placed on the surrounding environment or the AV itself to avoid compelling cyclists to carry devices on every trip. However, optional wearable devices can be used for added support. Results for versatility showed that AV-cyclist interfaces must be viewable from anywhere around the vehicle, and the AV’s intentions should be communicated in a simple, binary manner (i.e., AV-yielding or not yielding) to work consistently between traffic scenarios. Investigating cultural inclusivity showed that interfaces were needed to facilitate interaction regardless of the cultural setting. Cyclists accustomed to riding in mixed traffic found interface messages on AV intentions sufficient. However, those accustomed to greater segregation from vehicles needed to verify these messages with AV driving behaviours. For scalability, results showed that incorporating additional wearable devices was useful to avoid ambiguity in multi-cyclist situations and centralise information from multiple AVs. Multi-AV information should be communicated using visual and auditory signals without diverting cyclist attention from the road ahead, e.g. by integrating visual displays into the environment. The thesis contributes novel design guidelines for each design challenge. This is critical for supporting the large scale, global deployment of AVs and ensuring safe cycling experiences
Externalization of migration control: international legal guarantees against the erosion of refugee protection
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DWDM source with precise channel spacing and good reliability
Get PDFThis thesis discusses advancements in photonic integrated circuits, focusing on monolithic semiconductor laser arrays and narrow linewidth laser designs around 1550 nm. The research proposes efficient solutions to the challenges of laser fabrication and integration, contributing to high-capacity optical communication systems.
Four major innovations are presented. First, a four-channel laser array based on four-phase shifted distributed feedback (DFB) lasers was demonstrated. The array achieves a uniform 100 GHz channel spacing, with each laser exhibiting a single-mode suppression ratio (SMSR) exceeding 50 dB. The integration of a semiconductor optical amplifier enables an output power of 33 mW, making the array suitable for dense wavelength-division multiplexing (DWDM) applications. Second, a DFB laser with a distributed phase shift region at the cavity centre was developed to achieve narrow linewidth operation. Compared to conventional π phase-shifted DFB lasers, the optimised DPS design enables stable single-longitudinal-mode operation over a broader current range, with lower threshold current, higher slope efficiency, and improved SMSR. The minimum linewidth was reduced from 1.3 MHz to 220 kHz, demonstrating potential for high-precision applications such as LiDAR and coherent optical communications. Third, a novel grating modulation technique was proposed to enhance wavelength control in DFB laser arrays. By introducing an arithmetic phase progression, this method enables channel spacings of 0.493 nm, 0.949 nm, and 1.956 nm while maintaining a strong coupling coefficient and improving fabrication tolerance. Finally, asymmetric twin waveguide integration was implemented, demonstrating an integrated four-phase-shifted DFB laser array with 0.873 nm channel spacing, an SMSR exceeding 45 dB, and an electro absorption modulator extinction ratio over 10 dB. These advancements enable scalable, precise, and efficient photonic integration.
Collectively, this work advances semiconductor laser technology, offering new solutions for linewidth narrowing, wavelength control, and integration, with applications in telecommunications, metrology, and quantum technologies
In line or out of sync? Science, criminal law, and HIV: An in-depth assessment
Get PDFLaws criminalising HIV transmission and/or exposure are controversial measures and the subject of frequent debate. Beyond the philosophical arguments for or against their utility, another controversy remains: are these laws leading to unjust outcomes by relying on outdated science? This is the primary question addressed by this thesis. In pursuing this question, the subsequent chapters break down the history of criminalised HIV exposure and transmission in England and Scotland as well as the elements of the relevant offences. Medical and scientific evidence is most pertinent in these cases when assessing causation, recklessness, and harm. This thesis argues that, particularly where recklessness and harm are concerned, there is a gap between the law and science. The reason for this gap, it is submitted, owes largely to a narrative that exists in much of the case law which emphasises the underlying betrayal of trust. This narrative can serve as both a distracting element and as a factor which can exacerbate cognitive biases people are prone to. These biases can impact how risk and harm are perceived. In support of this assertion, recklessness and harm will be discussed both generally and in connection to criminalised HIV transmission specifically. Other areas will likewise be drawn upon as a basis of comparison, including English civil cases involving HIV and the laws of other common law jurisdictions. It is argued that recklessness should be assessed in a two-pronged approach which considers both the objective risk and the defendant’s subjective stance, and that the harm of HIV should remain a live issue assessed on a case-by-case basis. This thesis aims to highlight the importance of the law adjusting to changing medical advancements in order to protect the rights of a group of people that are already highly marginalised
Experimental identification of blade stall in axial and edgewise flight conditions
Get PDFThe recent resurgence of the airscrew propeller, growth in both military and civilian tiltrotor technology and successful operation of a rotorcraft on Mars has led to a reinvigoration of research surrounding blade stall in axial and edgewise conditions. Modern tiltrotor blades are designed to operate in both propeller and rotor mode, thus operating in underexplored regions of the operational flight envelope, where aerodynamic and aeroelastic instabilities may occur, leading to unfavourable and potentially fatal operational conditions. Despite several experimental investigations focused on blade stall over the past century, there is a clear lack of a comprehensive aerodynamic and aeroelastic experimental data set of sufficient resolution which can provide further insight into these complex phenomena and be used to validate high-fidelity numerical models. Therefore, within this body of work, state-of-the-art experimental test rigs were commissioned to develop a novel experimental methodology, primarily based on blade strain measurements, that can be utilised to identify operational conditions at which blades are stalled, for both axial and edgewise flight regimes.
Axial blade stall was investigated using the United Kingdom National Rotor Rig situated at the University of Glasgow De Havilland wind tunnel. A blade stall operational boundary was constructed for the MENtOR tiltrotor blade set through the use of key markers within the blade strain, wind tunnel velocity and motor data. It was shown for stalled conditions that the flap bending and torsional strain measurements departed from linear behaviour when increasing blade pitch with substantial growth in their standard deviation, up to twice the pre-stall value. Stall was also apparent in the strain spectra, exhibiting a significant non harmonic content and large distribution of signal energy. Unsteady flow generated by the stall acted as a broadband forcing term for the blade structural dynamics resulting in the identification of blade eigenmode frequencies, particularly the first flap bending mode. To support the validity of the developed stall boundary identification criteria, a multi measurement approach was implemented to identify blade stall, using independent measurement techniques including stereoscopic Digital Image Correlation and load measurements. Flap bending deflection measurements and load remeasure-ments were shown to correlate strongly with the identified stall conditions obtained using the stall boundary identification criteria.
Subsequently, an investigation using a single bladed rotor was performed at the University of Maryland towing tank to assess the viability of utilising measurements of the blade strain distribution to identify regions of reverse and separated flow in edgewise conditions. Reverse flow regions were identified through phase resolved measurements of rotor thrust, torque and pitching moment around the rotor azimuth. At large advance ratios where strong reverse flow effects occurred, phase resolved measurements of blade flap bending strain exhibited a strong agreement with load identified azimuthal locations at which the blade entered and exited the reverse flow region. Averaged and unsteady strain measurements displayed an identical trend to load measurements, demonstrating the applicability of strain distribution to identify stalled and reverse flow regions.
The results of this work have demonstrated the ability to use strain measurements to identify the presence of blade stall in both axial and edgewise conditions. Highlighting the capability to quickly, reliably and cost effectively develop blade stall boundaries when compared to more conventional experimental methods. Finally, the novel criteria developed within this work can be implemented across many technical readiness levels supporting academic and commercial blade testing activities
Impact of transcranial Alternating Current Stimulation and eye movements on attention-based EEG neurofeedback
No full textAbstract not currently available
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