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Discovering thermoelectric materials with modern machine learning approaches
Get PDFMachine learning is increasingly utilized to accelerate the discovery and design of new materials. Thermoelectrics are an important class of energy materials with the potential to help
address pressing environmental challenges. This thesis presents novel machine learning-based
methodologies for predicting material properties and generating crystal structures, with a focus on the discovery of new, and more effective, thermoelectric materials. First, a method is
introduced for deriving distributed representations of materials solely from their chemical formulas, which demonstrates competitive performance in predicting various properties, such as
formation energy and band gap. Next, an attention-based deep learning model is developed to
predict thermoelectric transport properties, which incorporates the distributed representations,
and proves capable of making useful predictions with a significantly reduced computational
cost compared to traditional ab initio methods. Finally, a generative model is proposed that is
capable of suggesting crystal structures for chemical compositions, which is vital for progressing from estimates of thermoelectric performance from composition, to deeper investigation
based on structure. The results from these studies demonstrate the potential for modern machine learning techniques in the field of materials discovery, and particularly for accelerating
the discovery of novel thermoelectrics
Қазақстандағы қаржылық бақылау жүйесіндегі мемлекеттік аудиттің орны (The place of public audit in the system of financial control in Kazakhstan)
Get PDFThis article discusses the role and importance of public audit in the system of financial control in Kazakhstan. Public audit is the main tool for ensuring transparency and accountability in the management of public financial resources, as well as an important element of maintaining economic security of the country. The purpose of the study is to determine the place, functions and tasks of public audit in the system of financial control of Kazakhstan, as well as to analyse its impact on economic security and management of public resources. The main directions of the study include the study of the structure and organisation of public audit, its main functions, identification of current problems and prospects for the development of this system. The scientific significance of the work lies in the systematisation of knowledge about public audit in Kazakhstan and a comprehensive analysis of its impact on the financial system of the country. Practical significance is to identify specific problems facing the public audit system and provide recommendations for their solution. The value of the study is determined by an in-depth study of the functions and tasks of public audit and identification of its impact on the management of public resources and economic security. The results of the study can become the basis for improving the public audit system. The practical significance of the results lies in the development of specific proposals to improve the efficiency of public audit bodies, ensure their independence, strengthen human resources and introduce modern technologies. These measures will contribute to improving the quality of public resource management and reducing corruption in Kazakhstan
Airline industry equities under external uncertainty shocks
Get PDFWe gauge the impact of news and other relevant external uncertainties facing airline firms via an equity market lens. Using local projections, we establish that rising investors’ fear shocks have long-lasting negative effects on airline industry equity returns, while increasing geopolitical, climate policy, and fuel cost uncertainties have comparatively short-lived impacts. Our results are robust to several alternative model specifications, including a pre-pandemic subsample. Based on our findings, we provide a promising avenue for future research in airline financial management
The impact of macroeconomic conditions on the performance of software, hardware and semiconductor sub-sector indices
Get PDFThis thesis explores the relationship between (a) the performance of the sub-sector
indices of the US Information Technology sector and (b) a set of macroeconomic
variables. More specifically, the study analyses the relationships between, on the one
hand, the indices of US Software & Services, US Hardware & Equipment, and US
Semiconductors & Semiconductor Equipment and, on the other, the US money supply,
US manufacturing activity, US long-term real interest rates and US inflation. Monthly
index and macroeconomic data were collected for the timeframe studied: 31
December 1998–31 January 2022. The Johansen cointegration analysis and the Vector
Error Correction Model (VECM) are used to determine long-term relationships. Given
the dramatic change in Software, Hardware and Semiconductor companies’ business
models following the Global Financial Crisis (GFC), the analysis is split into pre- and
post-GFC periods. The approach used is a differentiating one in which the design of an
econometric model is determined both by a bottom-up, fundamental analysis and by
the author’s practitioner experience.
Results suggest a stable, long-term relationship between sub-sector indices and
macroeconomic variables. All sub-sector indices show a positive relationship with
money supply both pre- and post-GFC. The Semiconductors index exhibits a positive
relationship with manufacturing activity pre-GFC yet a negative one post-GFC:
attributable to structural changes in the Semiconductors sub-sector. The Software
index shows a positive cointegration coefficient with long-term real interest rates both
pre- and post-GFC, a particularly surprising finding of this study. While the relationship
between the Hardware index and inflation is not statistically significant pre-GFC, the
index shows a positive relationship with inflation post-GFC. This is an expected
outcome which is driven by an increased dependence of Hardware firms on consumer
spending after the launch of the first iPhone in 2007.
This study closes a gap in the academic literature by analysing sub-sector indices and
thereby expanding the discussion – by going beyond composite and sector indices – on
the impact of macroeconomic variables on stock market indices. This is also one of only a handful of papers to analyse in detail the macroeconomic performance drivers
of the Information Technology sector.
The research will assist asset managers in better understanding the impact of
macroeconomic factors on the performance of Software, Hardware and
Semiconductor stocks. For investors, an appreciation of the findings of this thesis will
benefit their investment frameworks, allowing them to take more informed decisions
and consequently generate better risk-adjusted returns
Biomimicry in construction: glycoprotein-stabilised adobe bricks for enhanced compressive strength inspired by termites mounds
Get PDFEarth is a green building material with very low embodied energy and almost zero greenhouse gas emissions. However, it lacks strength and durability when used without stabilisation. By incorporating responsibly sourced
stabilisers, it is possible to enhance the strength of this material. In this study, adobe bricks stabilised using bioinspired stabilisers were investigated. This research was inspired by the high strength and durability of termite
mounds, exploring the stabiliser behind such robust natural constructions. Termites build their mounds by
incorporating a glycoprotein from their saliva to cement the sub-soil particles together. Biomimicry has been
employed to investigate the potential use of the termites’ construction stabiliser in adobe bricks. Three glycoproteins from meat and fish industry waste were identified as potential stabilisers in adobe bricks. Bovine serum
albumin (BSA) from cows’ blood, mucin from the porcine stomach, and gelatine from cold-water fish skin were
the three stabilisers used in this study. Two soils were used to prepare adobe bricks for testing. The primary soil
used in this study was from Devon in the United Kingdom (UK). The second soil was obtained from the Mayo
neighbourhood in Khartoum, Sudan, and used only in key tests. Adobe bricks were made and stabilised with
different concentrations of these bio-inspired stabilisers. Controlled unstabilised adobe bricks were used for
comparison. The bricks were tested for their unconfined compressive strength. The main conclusion of this study
is that BSA has proven its potential to be used as a stabiliser in earth construction. Using 0.5 % BSA resulted in a
17 % and 41 % increase in the unconfined compressive strength of the British and Sudanese adobe bricks,
respectively. In addition, using 5 % BSA resulted in a 203 % and 97 % increase in the unconfined compressive
strength of the British and Sudanese adobe bricks, respectively. The compressive strength of BSA-stabilised adobe bricks is higher than that of earth bricks stabilised using 5 % cement and 5 % lime reported in the literature.
Furthermore, the compressive strength of the 5 % BSA-stabilised adobe bricks is higher than the lower recommended compressive strength for the hollow concrete blocks in the UK. Hence, these BSA-stabilised adobe bricks
could substitute hollow concrete blocks to construct internal walls. The other stabilisers tested did not significantly improve the unconfined compressive strength of the adobe bricks. The study underscores the value of
biomimicry and proposes glycoproteins as viable natural stabilisers in earth construction, with further recommendations for in-depth research to optimise application methods and formulations
The profound influence of the North Atlantic Ocean on Northeast Asia: a comprehensive multi-model study
Get PDFWe assess the effects of the North Atlantic Sea surface temperature multidecadal variability on Northeast Asia using a set of sensitivity experiments (with a total of 530 ensemble members). We show that a warming of the North Atlantic Ocean leads to a strong and robust increase in temperature over Northeast Asia, which is replicated by a large majority of ensemble members. We show that the effect of the North Atlantic on Northeast Asia is model and season-dependent. We focus on two seasons, for which response to the North Atlantic Ocean is the most robust (autumn) and the less robust (spring) as indicated by the number of models that simulate a statistically significant change in surface air temperature. We use a clustering method to identify the sources of differences between models in simulating the effects of warming in the North Atlantic. We find that the primary mechanism linking the North Atlantic to Northeast Asia is a perturbation of the circumglobal teleconnection pattern (i.e., of the upper tropospheric atmospheric circulation), which allows modulation of the near-surface atmospheric circulation and an increase in temperature over East Asia. A second mechanism is related to the influence of the North Atlantic on the Pacific Ocean and the resulting effects on atmospheric circulation over Northeast Asia
Functionalisation of chitosan with methacryloyl and crotonoyl groups as a strategy to enhance its mucoadhesive properties
Get PDFMucoadhesive polymers are crucial for prolonging drug retention on mucosal surfaces. This study focuses on synthesising and characterising novel derivatives by reacting chitosan with crotonic and methacrylic anhydrides. The structure of the resulting derivatives was confirmed using proton-nuclear magnetic resonance spectroscopy and Fourier-transform infrared spectroscopy. It was established that the degree of substitution plays a crucial role in the pH-dependent solubility profiles and electrophoretic mobility of the chitosan derivatives. Spray-drying chitosan solutions enabled preparation of microparticles, whose mucoadhesive properties were evaluated using fluorescence flow-through studies and tensile test, demonstrating improved retention on sheep nasal mucosa for modified derivatives. Acute toxicity studies conducted in vivo using planaria and in vitro using MTT assay with the Caco-2 cell line, a model of the mucosal epithelium in vitro, showed that the novel derivatives are not cytotoxic. These findings emphasise the potential of tailored chitosan chemical modifications for enhancing transmucosal drug delivery
Descriptions of Anthrenus (s. str.) senegalensis, Anthrenus (s. str.) crypticus, a new species from Togo, and Anthrenus (s. str.) fosteri, a new species from Algeria (Coleoptera: Dermestidae: Megatominae)
Get PDFAll specimens labelled Anthrenus senegalensis were borrowed from the Natural History Museum, London. A. senegalensis is a poorly known species, so the aim is to provide a good description of the species associated with habitus and genitalia images. Three species were noted in the sample: A. senegalensis, A. crypticus sp. nov., and A. fosteri sp. nov.. A. crypticus and A. fosteri are described along with A. senegalensis, the most likely confusion species. Habitus and genitalia images of all three species are provide
Film editing: knowledge, practice, and scholarship
Get PDFThis thesis seeks to develop a more nuanced understanding of the discourses around
film editing from the privileged perspective of a film editor turned researcher. This research
examines the complex relationship between the theoretical and practice-based discussions on
film editing and expands on functions and techniques of editing that have enjoyed less
academic attention. An overriding concern of the project is to consider how practice can
enhance the study of film editing, above and beyond what written scholarship has offered.
The literature review investigates critical traditions around editing and compares this
with how editors talk and write about their work. The critical analysis of a series of case studies
looks at five films and related academic theories, exploring editing structures and the different
approaches involved. The thesis underscores the significance and importance of videographic
criticism as scholarly method, providing novel insights on films and facilitating an in-depth
investigation of film material, exploring editing strategies in a form closely aligned to the
original, where language-based explorations may not be so effective. The project also draws
on original interviews with recognized international industry experts to gain valuable insights
into how their current practices accommodate the traditional editing forms. An appendix,
providing full transcriptions of the interviews, completes the submitted material.
The project demonstrates the existing strengths of academic scholarship on editing but
foregrounds the benefits of drawing on other methods of understanding film editing, especially
considering rapid technological change and its implications for the established theories. The
results show that the value of the professional voice is a distinctive contribution to this thesis.
There is an increasing demand for practitioners to engage further with film scholarship,
especially considering the growing popularity and acceptance of videographic criticism, to
demystify certain aspects of editing that remain under-researched and to investigate practice
uninformed or unconcerned with theory
Optimizing the digital transformation capability for enhancing economic sustainability of entrepreneurial venture: the moderating role of entrepreneurial orientation
No full textDigital transformation relates to the deployment of digital technologies to improve business practices, culture, and customer experience to meet changing market needs. Digital transformation capabilities could also influence the environmental and social performance of entrepreneurial ventures. Against this backdrop, the aim of this study is to investigate how digital transformation capability could impact environmental and social performance as well as economic sustainability of entrepreneurial ventures. This study examines if there are any moderating impacts of entrepreneurial orientation on the relationships between digital transformation capability and its consequences. Also, this study uses different control variables to determine the impact on the economic sustainability of entrepreneurial ventures. With the support of a resource-based view and literature review, a research model has been developed conceptually, which was later validated using a covariance-based structural equation modeling technique with consideration of feedback from 312 entrepreneurs from different sectors and industries. The study found that there is a significant impact of digital transformation capability on environmental performance and social performance of entrepreneurial ventures, which, in turn, influences the economic sustainability of the entrepreneurial venture. This study also highlighted that there is a significant moderating impact of entrepreneurial orientation on different performances of entrepreneurial ventures