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Predicting passengers’ feedback rate for airport service quality
Get PDFAirport service quality evaluation is commonly found on social media sites, including Google Maps. The reviews by users of Google Maps are longer in terms of the number of words than those found on Twitter. They also include a rating, whereas those on Twitter need to be labelled. However, they are less well known than those on Twitter amongst researchers who focus on sentimental analysis. This study attempts to fill the gap in the current literature and develops architecture that is based on Long-Short Term Memory Neural Networks and Convolution Neural Networks. The combined model developed receives meta-data, such as the number of words in the review and the number of likes the review receives in addition to the key review words. The two models, the first of which predicts polarity and the second reviews ratings, were tested under several variations of parameters and showed consistency in results. The dataset was collected from Google Maps and focused on two crowded airports in the Arabic Peninsula (Doha and Dubai). They were found to be unbalanced, with positive reviews being more abundant than negative reviews.Transportation Research Interdisciplinary Perspective
Reassessing the warming impact of methane emissions from Irish livestock using GWP*: historical trends and sustainable futures
Get PDFMethane from livestock production contributes significantly to Ireland’s greenhouse gas emissions. Methane emissions are generally expressed as carbon dioxide equivalents (CO2e) using the global warming potential (GWP) metric, but this conversion may result in an inaccurate assessment, because methane has a much shorter atmospheric lifespan than CO2. This study calculated the CO2e of methane emissions from Irish livestock using the GWP and GWP* metrics, the latter of which accounts for the short-lived nature of atmospheric methane. Methane emissions from all Irish livestock (1961–2020) were included and three projected scenarios to 2050 were hypothesised: increasing emissions, decreasing emissions and constant emissions. The CO2e of methane from Irish livestock was found to be influenced by changes in the rate of emission over the preceding decades. Using the GWP* metric, declining populations of donkeys and horses from 1961 to 2000 were shown to cause atmospheric removals of methane when expressed as CO2e. Increasing populations of swine and non-dairy cattle (in response to industrial changes and European Union [EU] regulations) saw significant increases in the CO2e of methane emissions from these sources. Milk quotas caused a significant reduction in the CO2e of methane emissions from dairy cows, and atmospheric removals were observed in the years 1990–2012. GWP* indicated that the constant and decreasing future emission scenarios gave more significant reductions in CO2e than the GWP. These results indicate the importance of the effect of emission rate on the CO2e of methane from Irish livestock, which is accounted for using GWP*, but not by the conventional GWP.Irish Journal of Agricultural and Food Researc
Genes involved in auxin biosynthesis, transport and signalling underlie the extreme adventitious root phenotype of the tomato aer mutant
Get PDFThe use of tomato rootstocks has helped to alleviate the soaring abiotic stresses provoked by the adverse effects of climate change. Lateral and adventitious roots can improve topsoil exploration and nutrient uptake, shoot biomass and resulting overall yield. It is essential to understand the genetic basis of root structure development and how lateral and adventitious roots are produced. Existing mutant lines with specific root phenotypes are an excellent resource to analyse and comprehend the molecular basis of root developmental traits. The tomato aerial roots (aer) mutant exhibits an extreme adventitious rooting phenotype on the primary stem. It is known that this phenotype is associated with restricted polar auxin transport from the juvenile to the more mature stem, but prior to this study, the genetic loci responsible for the aer phenotype were unknown. We used genomic approaches to define the polygenic nature of the aer phenotype and provide evidence that increased expression of specific auxin biosynthesis, transport and signalling genes in different loci causes the initiation of adventitious root primordia in tomato stems. Our results allow the selection of different levels of adventitious rooting using molecular markers, potentially contributing to rootstock breeding strategies in grafted vegetable crops, especially in tomato. In crops vegetatively propagated as cuttings, such as fruit trees and cane fruits, orthologous genes may be useful for the selection of cultivars more amenable to propagation.The research was supported by BBSRC—UKRI funding; the RootLINK (BB/L01954X/1) and AdRoot (BB/S007970/1) projects.Theoretical and Applied Genetic
Optimal reusable rocket landing guidance: a cutting-edge approach integrating scientific machine learning and enhanced neural networks
Get PDFThis study presents an innovative approach that utilizes scientific machine learning and two types of enhanced neural networks for modeling a parametric guidance algorithm within the framework of ordinary differential equations to optimize the landing phase of reusable rockets. Our approach addresses various challenges, such as reducing prediction uncertainty, minimizing the need for extensive training data, improving convergence speed, decreasing computational complexity, and enhancing prediction accuracy for unseen data. We developed two distinct enhanced neural network architectures to achieve these objectives: Adaptive (AQResNet) and Rowdy Adaptive (RAQResNet) Quadratic Residual Neural Networks. These architectures exhibited outstanding performance in our simulations. Notably, the RAQResNet model achieved a validation loss approximately 300 times lower than the standard architecture with an equal number of trainable parameters and 50 times lower than the standard architecture with twice the number of trainable parameters. Furthermore, these models require significantly less computational power, enabling real-time computation on modern flight hardware. The inference times of our proposed models were measured in approximately microseconds on a single-board computer. Additionally, we conducted an extensive Monte Carlo analysis that considers a wide range of factors, extending beyond aerodynamic uncertainty, to assess the robustness of our models. The results demonstrate the impressive adaptability of our proposed guidance policy to new conditions and distributions outside the training domain. Overall, this study makes a substantial contribution to the field of reusable rocket landing guidance and establishes a foundation for future advancements.IEEE Acces
PDOPT: A Python library for Probabilistic Design space exploration and OPTimisation
Get PDFContemporary engineering design is characterised by products and systems with increasing
complexity coupled with tighter requirements and tolerances. This leads to high epistemic
uncertainty due to numerous possible configurations and a high number of design parameters.
Set-Based Design is a methodology capable of handling these design problems, by exploring
and evaluating as many alternatives as possible, before committing to a specific solution.
The Python package PDOPT aims to provide this capability without the high computational
cost associated with the factorial-based design of experiments methods. Additionally, PDOPT
performs the requirement mapping without explicit rule definition. Instead, it utilizes a
probabilistic machine learning model to identify the areas of the design space most promising
for user-provided requirements. This yields a plethora of feasible design points, assisting
designers in understanding the system behaviour and selecting the desired configurations for
further development.Journal of Open Source Softwar
Development of hybrid electrospun alginate-pulverized moringa composites
No full textThe consideration of biopolymers with natural products offers promising and effective materials with intrinsic and extrinsic properties that are utilized in several applications. Electrospinning is a method known for its unique and efficient performance in developing polymer-based nanofibers with tunable and diverse properties presented as good surface area, morphology, porosity, and fiber diameters during fabrication. In this work, we have developed an electrospun sodium alginate (SA) incorporated with pulverized Moringa oleifera seed powder (PMO) as a potential natural biosorbent material for water treatment applications. The developed fibers when observed using a scanning electron microscope (SEM), presented pure sodium alginate with smooth fiber (SAF) characteristics of an average diameter of about 515.09 nm (±114.33). Addition of pulverized Moringa oleifera at 0.5%, 2%, 4%, 6%, and 8% (w/w) reduces the fiber diameter to an average of about 240 nm with a few spindle-like pulverized Moringa oleifera particles beads of 300 nm (±77.97) 0.5% particle size and 110 nm (±32.19) with the clear observation of rougher spindle-like pulverized Moringa oleifera particle beads of 680 nm (±131.77) at 8% of alginate/Moringa oleifera fiber (AMF). The results from the rheology presented characteristic shear-thinning or pseudoplastic behaviour with a decline in viscosity, with characteristic behaviour as the shear rate increases, indicative of an ideal polymer solution suitable for the spinning process. Fourier transform infrared spectroscopy (FT-IR) shows the presence of amine and amide functional groups are prevalent on the alginate-impregnated moringa with water stability nanofibers and thermogravimetric analysis (TGA) with change in degradation properties in a clear indication and successful incorporation of the Moringa oleifera in the electrospun fiber. The key findings from this study position nanofibers as sustainable composites fiber for potential applications in water treatment, especifically heavy metal adsorption.We acknowledge the Petroleum Technology Development Fund (PTDF) of the Federal Republic of Nigeria for their unwavering support in funding the Research (No. PTDF/ED/OSS/PHD/AOO/ 1844/2020PHD152).RSC advance
Know thy enemy and know yourself – the role of operational data in managing the mines and booby trap threat in Vietnam, 1965–73
Get PDFVictim operated explosive devices (VOEDs) such as mines and booby traps, have been an enduring problem since their large-scale use started in the 1940s. While the overall problem is often known about in general terms, the real complexion of the problem was not necessarily fully appreciated. Eventually the need to understand the problem and the response to it was partially identified and acted upon in Vietnam through the collection and analysis of operational data. This did not solve the problem of mines and booby traps, but it did offer a means to better manage the threat.War in Histor
Contesting corporate responsibility in the Bangladesh garment industry: the local factory owner perspective
Get PDFIn the developing economy of Bangladesh, local factory owners in the garment industry have felt great pressure to improve factory safety, but the costs for those improvements are not shared by the global apparel firms that wield immense influence over them. Consequently, we examine whether multi-stakeholder initiatives (MSIs), as vehicles of corporate social responsibility (CSR), offer platforms for democratic oversight or merely serve as new arenas to exercise corporate power. Given their role in connecting global and local contexts and their history of safety incidents, local factory owners possess a unique perspective on the impact and contested nature of CSR in global supply chains. This article presents a qualitative study of MSIs in the Bangladesh garment industry, particularly after the Rana Plaza collapse. Through interviews with local factory owners and executive managers, we explore the reasons behind their opposition to CSR as exercised by global apparel firms, and the contestation of those practices by their local business association. Our findings lead us to conclude that garment industry MSIs are unlikely to be effective without labor procurement practices that harmonize global and local interests to mitigate the competitive pressures on local factory owners.The authors received no financial support for the research, authorship, and/or publication of this article
Exposure to benzene, toluene, ethylbenzene, and xylene (BTEX) at Nigeria's petrol stations: a review of current status, challenges and future directions
Get PDFIntroduction: In Nigeria, because of increasing population, urbanization, industrialization, and auto-mobilization, petrol is the most everyday non-edible commodity, and it is the leading petroleum product traded at the proliferating Nigeria's petrol stations (NPSs). However, because of inadequate occupational health and safety (OHS) regulatory measures, working at NPSs exposes petrol station workers (PSWs) to a large amount of hazardous benzene, toluene, ethylbenzene, and xylene (BTEX) compounds.
Methods: Studies on BTEX exposures among Nigerian PSWs are scarce. Thus, constraints in quantifying the health risks of BTEX limit stakeholders' ability to design practical risk assessment and risk control strategies. This paper reviews studies on the OHS of Nigerian PSWs at the NPSs.
Results: Although knowledge, attitude, and practices on OHS in NPSs vary from one Nigeria's study setting to another, generally, safety practices, awareness about hazards and personal protective equipment (PPE), and the use of PPE among PSWs fell below expectations. Additionally, air quality at NPSs was poor, with a high content of BTEX and levels of carbon monoxide, hydrogen sulfide, particulate matter, and formaldehyde higher than the World Health Organization guideline limits.
Discussion: Currently, regulatory bodies' effectiveness and accountability in safeguarding OHS at NPSs leave much to be desired. Understanding the OHS of NPSs would inform future initiatives, policies, and regulations that would promote the health and safety of workers at NPSs. However, further studies need to be conducted to describe the vulnerability of PSWs and other Nigerians who are occupationally exposed to BTEX pollution. More importantly, controlling air pollution from hazardous air pollutants like BTEX is an essential component of OHS and integral to attaining the Sustainable Development Goals (SDG) 3, 7, and 11.Frontiers in Public Healt
Reducing food loss and waste contributes to energy, economic and environmental sustainability
Get PDFFood loss and waste (FLW) reduction presents a major opportunity for enhancing the sustainability and resilience of the food supply chain. However, the lack of evidence regarding the scale and origins of FLW hinder determination of its environmental impact and prioritisation of mitigation action. We herein conducted a study to quantify FLW in the UK horticulture supply chain, and estimate its environmental impact as assessed through CO2 equivalent (CO2e) emissions. Through a metanalysis of existing literature supplemented with stakeholder engagement, we estimated that 2.4 Mt of fresh produce FLW is generated annually between farm gate and retail for home-grown and imported produce, representing 36% of total supply. FLW was perceived as an inevitable economic risk rather than a sustainability issue, driven by economic factors (e.g. labour shortage, price protectionism). The lack of economic incentives for FLW recovery (e.g. alternative processing) further compound FLW. Our results reveal that FLW contributes 1.7 Mt CO2e annually, constituting 27.2% of the total emissions of the fresh produce supply chain. Resource-intensive production, prolonged storage and complex handling needs generates substantial energy demand and concordant environmental impacts. The current over-reliance on cold chain management should be re-examined to disentangle the FLW-energy-environment nexus, especially given that the effects of global warming on the horticulture supply chain has yet to be examined. To effectively mitigate FLW, a holistic approach is imperative, encompassing policy and consumer-level changes alongside development of novel postharvest management strategies.The authors thank Engineering & Physical Sciences Research Council for financial support through the project EP/V042548/1.Journal of Cleaner Productio