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Open Access Policy for LSBU July 2023
Get PDFOA Policy approved by Research Committee on 21 September 2022, incorporating a Rights Retention Strategy for LSBU. Supersedes 2015 policy at https://doi.org/10.18744/PUB.000002
Does low-carbon pilot policy in China improve corporate profitability? The role of innovation and subsidy
Get PDFIn an effort to aggressively combat climate change, China implemented a low-carbon city pilot policy (LCCP) in 2010. This study analyzes the impact LCCP, which is a specific environmental regulation on firms' profitability and innovation performance. The study argues that LCCP has an impact on corporate profitability by enhancing corporate innovation. Based on the data of A-share listed enterprises from 2005 to 2020, this study employ a multi-period Differences-in-Differences (DID) method to explore whether and how the LCCP affects the profitability of enterprises. The study finds that: (1) LCCP can greatly increase enterprise profitability; (2) LCCP has a more prompt effect on the profitability of large companies; (3) LCCP increases innovation investment and financial subsidies, which in turn increases company profitability. The study enriches the body of knowledge on the effects of LCCP on large companies and SMEs, and provides crucial evidence base for the consequences of government's strategy to assist firms in achieving the low carbon growth
Phase prediction and experimental realisation of a new high entropy alloy using machine learning
Get PDFNearly ~10^8 types of High entropy alloys (HEAs) can be developed from about 64 elements in the periodic table. A major challenge for materials scientists and metallurgists at this stage is to predict their crystal structure and, therefore, their mechanical properties to reduce experimental efforts, which are energy and time intensive. Through this paper, we show that it is possible to use machine learning (ML) in this arena for phase prediction to develop novel HEA alloys. We tested five robust algorithms namely, K-nearest neighbours (KNN), support vector machine (SVM), decision tree classifier (DTC), random forest classifier (RFC) and XGBoost (XGB) in their vanilla form (base models) on a large dataset screened specifically from experimental data concerning HEA fabrication using melting and casting manufacturing methods. This was necessary to avoid the discrepancy inherent with comparing HEAs obtained from different synthesis routes as it causes spurious effects while treating an imbalanced data – an erroneous practice we observed in the reported literature.
We found that (i) RFC model predictions were more reliable in contrast to other models and (ii) the synthetic data augmentation is not a neat practice in materials science specially to develop HEAs, where it cannot assure phase information reliably. To substantiate our claim, we compared the vanilla RFC (V-RFC) model for original data (1200 datasets) with SMOTE-Tomek links augmented RFC (ST-RFC) model for the new datasets (1200 original+192 generated=1392 datasets). We found that although the ST-RFC model showed a higher average test accuracy of 92%, no significant breakthroughs were observed, when testing the number of correct and incorrect predictions using confusion matrix and ROC-AUC scores for individual phases. Based on our algorithm, we report the development of a new HEA (Ni25Cu18.75Fe25Co25Al6.25) exhibiting an FCC phase proving the robustness of our predictions
Quantum computing and materials science: A practical guide to applying quantum annealing to the configurational analysis of materials
Get PDFUsing quantum computers for computational chemistry and materials science will enable us to tackle problems that are intractable on classical computers. In this paper, we show how the relative energy of defective graphene structures can be calculated by using a quantum annealer. This simple system is used to guide the reader through the steps needed to translate a chemical structure (a set of atoms) and energy model to a representation that can be implemented on quantum annealers (a set of qubits). We discuss in detail how different energy contributions can be included in the model and what their effect is on the final result. The code used to run the simulation on D-Wave quantum annealers is made available as a Jupyter Notebook. This Tutorial was designed to be a quick-start guide for the computational chemists interested in running their first quantum annealing simulations. The methodology outlined in this paper represents the foundation for simulating more complex systems, such as solid solutions and disordered systems
Visible-Light-Active Iodide-Doped BiOBr Coatings for Sustainable Infrastructure
Get PDFThe search for efficient materials for sustainable infrastructure is an urgent challenge toward potential negative emission technologies and the global environmental crisis. Pleasant, efficient sunlight-activated coatings for applications in self-cleaning windows are sought in the glass industry, particularly those produced from scalable technologies. The current work presents visible-light-active iodide-doped BiOBr thin films fabricated using aerosol-assisted chemical vapor deposition. The impact of dopant concentration on the structural, morphological, and optical properties was studied systematically. The photocatalytic properties of the parent materials and as-deposited doped films were evaluated using the smart ink test. An optimized material was identified as containing 2.7 atom % iodide dopant. Insight into the photocatalytic behavior of these coatings was gathered from photoluminescence and photoelectrochemical studies. The optimum photocatalytic performance could be explained from a balance between photon absorption, charge generation, carrier separation, and charge transport properties under 450 nm irradiation. This optimized iodide-doped BiOBr coating is an excellent candidate for the photodegradation of volatile organic pollutants, with potential applications in self-cleaning windows and other surfaces
Enhancing supply chain innovation and operational agility through knowledge acquisition from the social media: A microfoundational approach
Get PDFThis paper presents an examination of the interlocks between knowledge acquisition from social media (KAfSM), organizational microfoundation structure and design (OMFSaD), supply chain innovation (SCI), and operational agility (OA). These interlocks were tested on data collected from 172 managers/directors/CEOs of 96 firms operating in nine manufacturing industry sectors in Malaysia. Our findings suggest that OMFSaD plays a key role when interlinked with KAfSM. Furthermore, OMFSaD is significantly associated with SCI and OA, and SCI significantly correlates with OA and partially mediates the relationship between OMFSaD and OA. Our study’s outcomes are consistent with our understanding of IT‐enabled organizational capabilities—thus contributing to dynamic capability theory—and suggest that KAfSM helps to revamp processes, routines, and business operations in frequently changing environments. In this paper, we draw implications for research and practice
Quantitative hydrogen and methane gas sensing via implementing AI based spectral analysis of plasma discharge
Get PDFIn this report we explore the feasibility of a quantitative gas detection system concept based on alternations in spectral emissions of a radio frequency power generated plasma in presence of a target gas. We then proceed with training a deep learning residual network computer vison model with the spectral data obtained from the plasma to be able to perform regressive calculation of the target gas content in the plasma. We explore this concept with hydrogen and methane gas present in the plasma at know quantities to evaluate the applicability of the concept as hydrogen or methane detection system. We will demonstrate that the system is well capable of quantitatively detecting either of the gases efficiently while it is challenging to estimate hydrogen content in presence of methane
Phosphinecarboxamide based InZnP QDs – an air tolerant route to luminescent III–V semiconductors
Get PDFWe describe a new synthetic methodology for the preparation of high quality, emission tuneable InP-based quantum dots (QDs) using a solid, air- and moisture-tolerant primary phosphine as a group-V precursor. This presents a significantly simpler synthetic pathway compared to the state-of-the-art precursors currently employed in phosphide quantum dot synthesis which are volatile, dangerous and air-sensitive, e.g. P(Si(CH3)3)3
Urban growth dynamics and expansion forms in 11 Tanzanian cities from 1990 to 2020
Get PDFWith rapid urban expansion across Tanzania, there is a need to institute steps to address factors and forms as well as impacts and challenges associated with the observed trend. This study’s aim is to use spatial urban landscape indices to analyze the spatial changes in urban forms, patterns, and rates across 11 urban centers in Tanzania over a 30-year study period (1990–2020). During the past three decades, urban lands of 11 cities and town in Tanzania have grown by a total of 480 km2. Leapfrog growth was found as the most dominant form of urban expansion in Tanzania while Dodoma, the capital city of Tanzania, had the highest rate of urban expansion when compared to all other individual cities. The most robust and significant interaction of the AWMLEI and MLEI was found in Kigoma, Arusha, Mtwara, Mafinga, and Tunduma cities. In contrast, Mbeya agricultural city, Arusha the tourist city, Tabora, and Geita Lake zone areas did show their own peculiarities revealing an interesting spatial temporal variation in rate and form of expansion. The outcome of this study reveals that the influence and management of economic and socio-cultural opportunities will be an effective tool for the determination of the rapidly expanding cities and towns of Tanzania
The paradox of pornography - sexuality and problematic pornography use
Get PDFThe experiences of sexual minority men who report self-perceived problematic pornography use is under theorised and not well understood despite controversial and conflicting research into the phenomena in heterosexual male populations. This study aimed to widen the conversation to consider the experience of sexuality in relation to self-perceived problematic pornography use, rather than contribute to literature that debates the definition and aetiology of problematic pornography use. Semi-structured online qualitative interviews were conducted with three sexuality minority men who self-reported problematic pornography use. Interpretive phenomenological analysis was used to develop themes. Five themes pertinent to understanding the participants experiences with problematic pornography use were developed: problematised sexuality, pornography as liberator, pornography as corrupter, reform, and relapse and restore. The themes highlight three men’s relationship with their sexuality as a feature of their self-perceived problematic pornography use. The research suggests that idiographic experiences of self-perceived problematic pornography use are influenced and maintained by an incongruent and conflicting relationship between an individual’s own experiences of sexuality and self-perceptions of pornography use. Limitations and future research recommendations are discussed