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The impact of analysis in the investigation of LBA glass production, transport and exchange and the role of women in this system
Get PDFBraekmans, D. - Associate supervisorThe study of Late Bronze Age (LBA) glasses has developed significantly over the last few decades. The advance of analytical methods capable of the sensitive detection of major, minor and trace elements have enabled researchers in this field to gain a greater understanding of LBA glass compositions in addition to being able to distinguish between glasses manufactured in Egypt and Mesopotamia, the two regions believed to have been the original innovator of glass. This thesis examines a series of LBA glasses excavated from historically significant sites in Egypt, Sinai and the Levant using Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS). The analysis of unanalysed material from an undisturbed tomb in Gurob, the only confirmed harem palace in Egypt, the temple of Hathor, in Serabit, Sinai and the strategically important site of Tall Zirā’a in the Levant are discussed in this thesis. Early glasses from KV35, the tomb of Amenhotep II (1427-1400 BCE) are examined as part of this thesis: these glasses were previously analysed using scanning electron microscopy; however, this research re-examines the material using LA-ICP-MS, thereby providing trace element data of several colours to determine the provenance of these early royal glasses in addition to presenting trace element data for some of the earliest Egyptian glass colouring strategies. By assessing the strategic importance of the sites in conjunction with the elemental analyses, colouring strategies and provenance of the glasses connected with the sites, this research answers questions about where the first glasses were made and what information the context tells us about the first glasses ever produced. This thesis also readdresses the importance that women played in the transportation and distribution of glass in the LBA. This research also examines the compositional changes in LBA glasses to identify key markers which can be used to date glasses by providing a production era, and consequently indicate the workshops which produced them. Finally, this thesis discusses the control and the volumes of glass moved in the LBA and proposes a model for the LBA glass system
Crash-proof and sustainable polymer-based composites in modern day transportation systems: a review on fabrication of lightweight components for land, sea and air travels
No full textThe need for advanced materials that are lightweight, durable and sustainable in the transportation sector in the recent times cannot be overemphasized. Previously, the focus was solely on endurance and crashworthiness without environmental considerations. However, due to environmental concerns in recent times, researchers are now focusing on lightweight and biodegradable materials that are sturdy, crash-proof, and sustainable. In other to achieve these, when selecting materials for transportation applications, many criteria are typically taken into consideration to cater for the divergence in the environment that the materials will be exposed to in service. Thus, polymer-based materials have been discovered to be appropriate for these purposes based on their inherent qualities such as lightweight, processing flexibility, acceptable properties, availability, economic viability and aesthetics. Therefore, most components of modern-day transportation gadgets and appliances are primarily developed from polymer-based composite materials. This review presents various parts of these gadgets/appliances such as; automotive, ship, train and airplanes that are being used for transportation systems that were produced from polymer-based composite materials. As emerging materials, components from polymer-based composites improve fuel efficiency and promote viable transportation. Hence, the progressive application and future benefits of polymer-based composites as lightweight materials in the transportation industry were the focus of this review. Key policies and regulatory frameworks influencing material selection across different sectors were provided while polymer-based composite materials in different modern day transportation systems like electric cars, naval ships, high-speed trains, and aircraft such as the Boeing 787 were identified and specified.Next Material
Integrating environmental sustainability into set-up efficiency: Eco-efficient Quick Changeover
No full textIn an era of increasing environmental and competitive pressures, manufacturing firms are continually challenged to improve production efficiency while minimizing ecological impacts. This paper introduces a novel Lean methodology named Eco-efficient Quick Changeover (EQC). It emerges as a strategic response to these dual imperatives, integrating the rapid set-up principles of Lean manufacturing with comprehensive sustainability considerations. EQC employs a systematic four-phase approach that begins with assembling a multidisciplinary team, followed by quantifying both time and environmental losses through an innovative Losses Matrix, examining the interdependencies of these losses via a Cause and Effect Matrix, and ultimately prioritizing corrective actions through the Ranking Matrix with a novel Green Set-up Index. A case study conducted in a plastic water bottle production facility revealed that this integrated strategy can reduce changeover time by 72%, lower energy consumption by 62%, and achieve substantial reductions in water usage, CO₂-equivalent emissions, and waste generation. These results underscore the potential of EQC to deliver significant operational improvements while advancing environmental performance, thereby offering a holistic framework that aligns with current sustainable development objectives.The International Journal of Advanced Manufacturing Technolog
Context-aware intrusion detection in vehicular communication networks: enhanced attack modeling and dataset
No full textThe data underpinning the findings of this study are openly available in the Mendeley Data repository under the title Comprehensive Vehicular Communication Network Attack Dataset, licensed under CC BY 4.0. The dataset contains the raw data that were used for experiments leading to the results presented in the manuscript and can be accessed via the DOI: https://doi.org/10.17632/x7tdmsf27x.1 This dataset is essential for replicating all results reported in the article.Vehicular Communication Networks (VCNs) are essential for autonomous vehicles and Intelligent Transportation Systems but face challenges in security vulnerabilities and data sparsity. Traditional attack models inadequately represent VCN dynamics, weakening threat detection, while existing datasets lack real-world mobility and spatiotemporal details. This study addresses these gaps by developing a comprehensive attack simulation framework, enhancing critical network attacks i.e. position spoofing, Sybil, and wormhole through realistic mobility patterns, positional dynamics, and temporal interactions. The resulting dataset contains legitimate and malicious instances: Spoofing (45,975 legitimate, 589 malicious), Wormhole (52,237 legitimate, 5,219 malicious), and Sybil (14,829 legitimate, 1,753 malicious). It includes essential vehicular-specific features such as mobility dynamics, inter-vehicle distances, and end-to-end communication patterns. For validation, machine learning algorithms, including Random Forest, K-Nearest Neighbors, and Logistic Regression were employed. Detection performance was evaluated using accuracy, precision, recall, and two F1-score variants (standard and macro). Results indicate high detection efficacy, with Random Forest achieving accuracy between 93.6% and 99.8% and F1-macro scores from 88.5% to 97.7%. Compared to previous studies lacking spatiotemporal considerations, our dataset’s enhanced realism demonstrates significant potential in advancing data-driven anomaly detection and real-world threat mitigation in dynamic vehicular environments.Applied Artificial Intelligenc
Punic people were genetically diverse with almost no Levantine ancestors
Get PDFPlease see the document for a full list of funding organisations.The maritime Phoenician civilization from the Levant transformed the entire Mediterranean during the first millennium bce1,2,3. However, the extent of human movement between the Levantine Phoenician homeland and Phoenician–Punic settlements in the central and western Mediterranean has been unclear in the absence of comprehensive ancient DNA studies. Here, we generated genome-wide data for 210 individuals, including 196 from 14 sites traditionally identified as Phoenician and Punic in the Levant, North Africa, Iberia, Sicily, Sardinia and Ibiza, and an early Iron Age individual from Algeria. Levantine Phoenicians made little genetic contribution to Punic settlements in the central and western Mediterranean between the sixth and second centuries bce, despite abundant archaeological evidence of cultural, historical, linguistic and religious links4. Instead, these inheritors of Levantine Phoenician culture derived most of their ancestry from a genetic profile similar to that of Sicily and the Aegean. Much of the remaining ancestry originated from North Africa, reflecting the growing influence of Carthage5. However, this was a minority contributor of ancestry in all of the sampled sites, including in Carthage itself. Different Punic sites across the central and western Mediterranean show similar patterns of high genetic diversity. We also detect genetic relationships across the Mediterranean, reflecting shared demographic processes that shaped the Punic world.Natur
Adaptive UAV control with sensor and actuator faults recovery
Get PDFThis paper presents an adaptive fault-tolerant control strategy tailored for fixed-wing unmanned aerial vehicles (UAV) operating under adverse conditions such as icing. Using radial basis function neural networks and nonlinear dynamic inversion, the proposed framework effectively handles simultaneous actuator and sensor faults with arbitrary nonlinear dynamics caused by environmental effects, model uncertainties and external disturbances. A nonlinear disturbance observer is incorporated for accurate sensor fault detection and estimation, thereby enhancing the robustness of the control system. The integration of the radial basis function neural network enables an adaptive estimation of the faults, ensuring accurate fault compensation and system stability under challenging conditions. The observer is optimised to minimise the deviation of the closed-loop dynamics eigenvalues from the assigned eigenvalues and to approach unity observer steady-state gain. The stability of the control architecture is mathematically proven using Lyapunov analysis, and the performance of the approach is validated through numerical simulations on a six Degrees of Freedom fixed-wing unmanned aerial vehicles model. The results show superior performance and robustness to challenging fault scenarios. This research provides a comprehensive fault management solution that enhances the safety and reliability of unmanned aircraft operations in extreme environments.Aerospac
Lane centerline extraction based on surveyed boundaries: an efficient approach using maximal disks
Get PDFMaps of road layouts play an essential role in autonomous driving, and it is often advantageous to represent them in a compact form, using a sparse set of surveyed points of the lane boundaries. While lane centerlines are valuable references in the prediction and planning of trajectories, most centerline extraction methods only achieve satisfactory accuracy with high computational cost and limited performance in sparsely described scenarios. This paper explores the problem of centerline extraction based on a sparse set of border points, evaluating the performance of different approaches on both a self-created and a public dataset, and proposing a novel method to extract the lane centerline by searching and linking the internal maximal circles along the lane. Compared with other centerline extraction methods producing similar numbers of center points, the proposed approach is significantly more accurate: in our experiments, based on a self-created dataset of road layouts, it achieves a max deviation below 0.15 m and an overall RMSE less than 0.01 m, against the respective values of 1.7 m and 0.35 m for a popular approach based on Voronoi tessellation, and 1 m and 0.25 m for an alternative approach based on distance transform.This work was supported in part by the China Scholarship Council under Grant No. 202108690001 and the Graduate Research and Innovation Projects of Jiangsu Province under Grant KYCX21_3334.Sensor
In situ growth of mycelium in a lignocellulosic scaffold enabled by cellulose nanofibrils for lightweight insulation
Get PDFMycelium-lignocellulosic fiber composites (MLFCs) offer a promising sustainable alternative to lightweight, petroleum-based materials and are gaining significant interest across various sectors. However, creating low-density MLFCs that provide superior thermal and sound insulation properties along with good mechanical strength remains a substantial challenge. In-mold packing is the primary fabrication process explored so far for MLFCs, limiting the ability to design complex shapes, and expanding potential applications. Growing mycelium on pre-produced low-density lignocellulosic foam scaffold substrates is an innovative process that represents a promising, yet underexplored, approach for MLFCs. This approach offers the potential for design flexibility and enhanced structural properties. In this study, hybrid low-density foams made from lignocellulosic fibers, cellulose nanofibrils (CNFs), and mycelium (Trametes versicolor) were developed and assessed as foam-like insulation materials. A foam-forming method enabled by a surfactant was used to prepare low-density foam scaffold substrates from hardwood and softwood fibers with CNFs as a binder. The raw scaffold substrates and the final MLFCs were characterized for thermal conductivity, sound absorption, water resistance, mechanical strength, and morphological properties. The composites demonstrated excellent thermal insulation, soundproofing, and mechanical strength, as well as thermal and sound properties comparable to or even better than expanded polystyrene (sound absorption coefficient > 0.9 at 1600 Hz). Overall, the results showed that MLFCs have strong potential for further exploration in semi-structural applications, such as lightweight insulating infill panels and protective packaging, offering environmentally friendly and resource-efficient solutions for the construction insulation and packaging markets.This material is based upon work supported by the US Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy, Advanced Materials and Manufacturing Office under CPS Agreement 35863, and Oak Ridge National Laboratory/University of Maine SM2ART program with research and resources used at the School of Forest Resources and the Chemical and Biomedical Engineering department at University of Maine.Composites Part A: Applied Science and Manufacturin
Adopting net-zero supply chains: integrated model of TOE and TAM in emerging economy context
Get PDFIndustries across the globe are making arduous efforts to mitigate emissions and use greener ways of transporting goods and delivering services. The supply chain includes all the activities which involve producing, transporting, and distributing goods and services, contributing to a major portion of worldwide emissions. Road transport contributes majorly to emissions; therefore, focusing on net-zero supply chains (NZSCs) is imperative. Yet, there are several challenges in the net-zero supply chain adoption pathway. Hence, in the presented study, the Technology, Organizational, and Environment and Technology Acceptance Model integrated framework determined behavioral intentions toward adopting NZSCs. The questionnaire was developed, and 206 responses were collected. Structural Equation Modeling was used to assess the proposed research model. Various constructs analyzed under the Technology, Organizational, and Environment framework were green modes of transportation (GMT), lean green integrated digital innovations (LGDI), Management Support (MS), Organizational Competency (OC), Industry Partnership and Collaborations (IPC), and Government Rules and Regulations (GRR). Similarly, perceived usefulness (PU) and perceived ease of use (PEU) constructs were analyzed under the Technology Acceptance Model framework. Moreover, the mediation analysis of perceived usefulness and perceived ease of use constructs was analyzed between distinct constructs and intention to adopt NZSCs. Government Rules and Regulations are found to have a strong role in mitigating environmental pollution and achieving sustainable development goals. Also, green modes of transportation do not have significant relationship between perceived usefulness. Likewise, relationship between organizational culture and perceived ease of use does not hold.Sustainable Future