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Situational support and information security behavioural intention: a comparative study using conservation of resources theory
Get PDFThe formation of information security behavioural intention (ISBI) can be complex and dynamic in different contexts. This paper aims to examine and compare different users’ ISBI formalisation mechanisms when dealing with their personal affairs (non-work users) and organisational affairs (work users). Drawing on two principles of Conservation of Resources (COR) theory (i.e. resource loss principle, and resource gain principle), we developed two models to examine how situational support affects ISBI formation. The results of a study of 432 non-worker users and 261 work users indicate a curvilinear relationship between situational support and ISBI through subjective norms and risk perception for non-worker users, whilst a linear relationship via subjective norms is found for worker users. This is the first time that COR has been applied to explain the formation of ISBI. The findings broaden the research scope of individuals’ ISBI by revealing how situational support affects the formalisation mechanism for different users in cross-contexts. The theoretical and practical implications of the findings and the future study are discussed.This work was supported by National Social Science Foundation of China (Education Science Youth Project) “Study on the cybersecurity talents demand matching mechanism and cultivation path under the Strategy of Cyber Power” [Grant Number CIA200273]
Industry 4.0: critical investigations and synthesis of key findings
Get PDFThe concept of Industry 4.0 has been one of the most debated and trending topics over the last few years. Progressively, it has attracted the attention of academicians, practitioners, and policymakers worldwide. However, there needs to be more systematic review of research in the current literature that captures the current state of this new paradigm. This study aims to address this gap by conducting a comprehensive review of Industry 4.0 previous studies to identify its technological, organisational, and managerial enablers, as well as its implementation challenges and benefits. A systematic literature review was conducted, in which 244 peer-reviewed journal papers were analysed in the Scopus database until the end of May 2022. This study excluded conference papers, book chapters, and journal papers not written in English. The study indicated that industry 4.0 is still an immature topic, and applying this new paradigm is not a matter of technology only. Organisational and managerial aspects should be considered. Additionally, the transition towards Industry 4.0 is a complex task, many obstacles exist, and manufacturing companies should be aware of these challenges for successfully implementing this new paradigm. The obtained results in this study synthesise recent studies published on Industry 4.0 and provide a comprehensive picture of Industry 4.0 and potential research directions for future research. Also, this study offers significant guidelines for managers interested in implementing Industry 4.0.Management Review Quarterl
Energy-based aerodynamic loss and recovery characteristics of adiabatic and heated fuselages
Get PDFAn energy-based aerodynamic analysis of the mechanical loss generation and potential energy/exergy recovery mechanisms is carried out for adiabatic and heated 2D axisymmetric flows over fuselage-shaped axisymmetric bodies. A generality of these mechanisms is obtained from dimensional analysis by appropriately scaling the freestream Reynolds and Mach numbers, while varying a reference fuselage’s fineness ratio. Thermo-aerodynamic implications and synergies of boundary-layer heating on the loss distribution, energy, and heat exergy recovery potentials are further considered for varying wall temperature ratios. The result is a clear identification of partial dynamic similarity and heat transfer effects on flow mechanisms such as shear layers, separation bubbles, and shockwaves of axisymmetric flows, and subsequent implications on loss distribution and energy recovery characteristics relating to boundary-layer ingestion. The analysis indicates that dissipating heat from aircraft surfaces aids, circumstantially, to drag reduction of unpowered fuselage bodies and increases, relative to the adiabatic, the recoverable energy fraction available for the boundary-layer ingestion propulsor, by strategically manipulating the loss distribution, while removing excess heat from the aircraft’s subsystem (batteries, fuel cells). Finally, an approach to assess the feasibility of exergetic heat recuperation as a possible means of useful work extraction and improved aerodynamic performance is explicitly introduced and discussed in the paper.Journal of Aircraf
A hybrid ensemble machine learning approach for arrival flight delay classification prediction using voting aggregation technique
Get PDFThe number of flights keeps increasing with the development of civil aviation, and flight delays have become a severe issue of concern to the aviation industry. The need for reliable flight delay classification and prediction cannot be overemphasised because of its importance. In this research, we classify arrival flight delay using a hybrid ensemble machine learning algorithm based on voting aggregation. Each ensemble’s architecture consists of four supervised machine learning algorithms: Logistic Regression, Decision Tree, Support Vector Classifier and Random Forest. We conducted a comparative experiment using the United States Bureau of Statistics dataset to verify the efficacy of our proposed approach against other benchmark approaches. We employ multiple evaluation metrics to check the performance of our proposed model comprehensively. Accuracy, Recall, Precision, F1-Score, AUC Score, and ROC curve. Our experimental results show that our model outperforms the benchmark techniques on the binary classification of flight delays task. Hence, the hybrid ensemble model presented in this research can be used as a decision-support model to improve the flight scheduling management system design to assist the airline and airport operation managers and passengers with improved travel itineraries management.2023 AIAA Aviation and Aeronautics Forum and Exposition (AIAA AVIATION Forum
Techno-economic analysis of 2,3-butanediol production from sugarcane bagasse
Get PDFSugarcane bagasse (SCB) is a significant agricultural residue generated by sugar mills based on sugarcane crop. Valorizing carbohydrate-rich SCB provides an opportunity to improve the profitability of sugar mills with simultaneous production of value-added chemicals, such as 2,3-butanediol (BDO). BDO is a prospective platform chemical with multitude of applications and huge derivative potential. This work presents the techno-economic and profitability analysis for fermentative production of BDO utilizing 96 MT of SCB per day. The study considers plant operation in five scenarios representing the biorefinery annexed to a sugar mill, centralized and decentralized units, and conversion of only xylose or total carbohydrates of SCB. Based on the analysis, the net unit production cost of BDO in the different scenarios ranged from 1.13 to 2.28 US/kg. Use of the hemicellulose fraction alone was shown to result in an economically viable plant; however, this was dependent on the condition that the plant would be annexed to a sugar mill which could supply utilities and the feedstock free of cost. A standalone facility where the feedstock and utilities were procured was predicted to be economically feasible with a net present value of about 72 million US$, when both hemicellulose and cellulose fractions of SCB were utilized for BDO production. Sensitivity analysis was also conducted to highlight some key parameters affecting plant economics.ACS Sustainable Chemistry and Engineerin
Fermentative valorisation of xylose-rich hemicellulosic hydrolysates from agricultural waste residues for lactic acid production under non-sterile conditions
Get PDFLactic acid (LA) is a platform chemical with diverse industrial applications. Presently, commercial production of LA is dominated by microbial fermentation using sugary or starch-based feedstocks. Research pursuits emphasizing towards sustainable production of LA using non-edible and renewable feedstocks have accelerated the use of lignocellulosic biomass (LCB). The present study focuses on the valorisation of xylose derived from sugarcane bagasse (SCB) and olive pits (OP) through hydrothermal and dilute acid pretreatment, respectively. The xylose-rich hydrolysate obtained was used for LA production by homo-fermentative and thermophilic Bacillus coagulans DSM2314 strain under non-sterile conditions. The fed-batch mode of fermentation resulted in maximum LA titers of 97.8, 52.4 and 61.3 g/L with a yield of 0.77, 0.66 and 0.71 g/g using pure xylose, xylose-rich SCB and OP hydrolysates, respectively. Further, a two-step aqueous two-phase system (ATPS) extraction technique was employed for the separation and recovery of LA accumulated on pure and crude xylose. The LA recovery was 45 – 65% in the first step and enhanced to 80–90% in the second step.The study demonstrated an efficient integrated biorefinery approach to valorising the xylose-rich stream for cost-effective LA production and recovery.Biotechnology and Biological Sciences Research Council (BBSRC): BB/S011951/1.
Engineering and Physical Sciences Research Council (EPSRC): EP/L016389/1.
Innovate UK.
Department of Biotechnology, IndiaWaste Managemen
Lignocellulose-derived arabinose for energy and chemicals synthesis through microbial cell factories: a review
Get PDFThe exploration of natural substrates for microbial conversion to synthesize industrial platform and fuel chemicals seems to be inevitable within a circular bioeconomy context. Hemicellulose is a natural carbohydrate polymer consisting of a variety of pentose (C5) sugar monomers such as arabinose, mannose, erythrose, and xylose. Among the C5 sugars, L-arabinose (L-Ara) is the second-most-abundant pentose sugar in the lignocellulosic biomass after xylose. L-Ara has been used as an industrial carbon source to produce several value-added chemicals such as putrescine, which is used to synthesize polymers in the textile industry; sugar alcohols that are used as sweeteners in diet foods; and amino acids such as L-lysine, L-glutamate, L-arginine, and L-ornithine, which are used in nutritional supplements, fertilizers, and other products in the food and beverage industries. L-Ara, a natural non-caloric sweetener, is used as a substitute in the food and beverage industry, when the risk of blood sugar and lipid levels could be reduced. Major use of L-Ara is also found in the medical and pharmaceutical sectors to treat several conditions, including mineral absorption disorder, constipation, and diabetes, among others. In recent years, there has been a rising interest in synthesizing various sugar alcohols and derivatives, including arabitol, xylitol, and 2,3-butanediol, through the modification of producer organisms either genetically or metabolically to produce value-added products. Understanding the current demand and the need to increase the diversified production of industrial green chemicals with the reduced waste of useful lignocellulosic resources, this review focuses on the background of L-Ara and its various sources, microbes that utilize L-Ara to produce high-value-added products, and the future prospects for strain improvements to increase the yield of high-value-added products.Processe
Analysis of the self-healing capability of thermoplastic elastomer capsules in a polymeric beam structure based on strain energy release behaviour during crack growth
Get PDFThe objective of this study was to investigate the elastic and plastic responses of 3D-printed thermoplastic elastomer (TPE) beams under various bending loads. The study also aimed to develop a self-healing mechanism using origami TPE capsules embedded within an ABS structure. These cross-shaped capsules have the ability to be either folded or elastically deformed. When a crack occurs in the ABS structure, the strain is released, causing the TPE capsule to unfold along the crack direction, thereby enhancing the crack resistance of the ABS structure. The enhanced ability to resist cracks was confirmed through a delamination test on a double cantilever specimen subjected to quasi-static load conditions. Consistent test outcomes highlighted how the self-healing process influenced the development of structural cracks. These results indicate that the suggested self-healing mechanism has the potential to be a unique addition to current methods, which mostly rely on external healing agents.Polymer
How do grand challenges determine, drive and influence the innovation efforts of for-profit firms? a multidimensional analysis
Get PDFWhile raising concerns, the recent proliferation of grand challenges has sparked interest in the role played by innovation in causing them, and in how the attempts made to fix them may cause even greater challenges that present themselves down the line. This article provides an analysis of the bibliographic metadata, published between 2002 and 2020, focusing explicitly on the private-for-profit sector. By identifying common themes from 66 documents, a framework highlighting the shared concerns and research trajectories was derived. Our results are illustrated and discussed along 11 research themes. We contribute theoretically by identifying the innovation efforts of for-profit firms that directly relate to grand challenges, through two cases of carbon capture and storage and deep-sea mining. We conclude that a more holistic understanding of innovation and its many possible consequences needs to be developed. We highlight the limitations of perspectives that do not always take full account of the potential divergence of interests between stakeholders, and, how fuller input by a greater cross-section of stakeholders may help identify any negative effects of innovations at an earlier stage. Informed by recent extensions of social innovation theory, we explore the potential for synthesis around a pragmatic understanding of institutions, stakeholders, and the nature and quality of ties that bind them
Laboratory bistatic synthetic aperture radar coherent change detection investigation
Get PDFSynthetic Aperture Radar (SAR) Coherent Change Detection (CCD) allows for the detection of very small scene changes. This is particularly useful for reconnaissance and surveillance as small changes such as vehicle tracks can be identified. In some situations, it is desirable to rapidly collect repeat pass SAR images for use in change detection, and multistatic geometries may facilitate this. Such repeat passes may however have significant baselines, particularly for satellite-based platforms, though CCD products are reliant on high coherence for good interpretability. This work investigates the sources and levels of incoherence associated with bistatic SAR imagery with increasing baselines using simulations and measured laboratory data.Electronics Letter