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Advancements in PCB Components Recognition Using WaferCaps: A Data Fusion and Deep Learning Approach
Get PDFData Availability Statement:
Data supporting the findings of this study are unavailable due to privacy restrictions.Microelectronics and electronic products are integral to our increasingly connected world, facing constant challenges in terms of quality, security, and provenance. As technology advances and becomes more complex, the demand for automated solutions to verify the quality and origin of components assembled on printed circuit boards (PCBs) is skyrocketing. This paper proposes an innovative approach to detecting and classifying microelectronic components with impressive accuracy and reliability, paving the way for a more efficient and safer electronics industry. Our approach introduces significant advancements by integrating optical and X-ray imaging, overcoming the limitations of traditional methods that rely on a single imaging modality. This method uses a novel data fusion technique that enhances feature visibility and detectability across various component types, crucial for densely packed PCBs. By leveraging the WaferCaps capsule network, our system improves spatial hierarchy and dynamic routing capabilities, leading to robust and accurate classifications. We employ decision-level fusion across multiple classifiers trained on different representations—optical, X-ray, and fused images—enhancing accuracy by synergistically combining their predictive strengths. This comprehensive method directly addresses challenges surrounding concurrency, reliability, availability, and resolution in component identification. Through extensive experiments, we demonstrate that our approach not only significantly improves classification metrics but also enhances the learning and identification processes of PCB components, achieving a remarkable total accuracy of 95.2%. Our findings offer a substantial contribution to the ongoing development of reliable and accurate automatic inspection solutions in the electronics manufacturing sector.This research received no external funding
Computational fluid dynamics analysis of the fluid environment of 3D printed gradient structure in interfacial tissue engineering
Get PDFMass transport properties within three-dimensional (3D) scaffold are essential for tissue regeneration, such as various fluid environmental cues influence mesenchymal stem cells differentiation. Recently, 3D printing has been emerging as a new technology for scaffold fabrication by controlling the scaffold pore geometry to affect cell growth environment. In this study, the flow field within scaffolds in a perfusion system was investigated with uniform structures, single gradient structures and complex gradient structures using computational fluid dynamics (CFD) method. The CFD results from those uniform structures indicate the fluid velocity and fluid shear stress within the scaffold structure increased as the filament diameter increasing, pore width decreasing, pore shape decreased from 90° to 15°, and layer configuration changing from lattice to stagger structure. By assembling those uniform structure as single gradient structures, it is noted that the fluid dynamic characterisation within the scaffold remains the same as the corresponding uniform structures. A complex gradient structure was designed to mimic natural osteochondral tissue by assembly the uniform structures of filament diameter, pore width, pore shape and layer configuration. The results show that the fluid velocity and fluid shear stress within the complex gradient structure distribute gradually increasing and their maximum magnitude were from 1.15 to 3.20 mm/s, and from 12 to 39 mPa, respectively. CFD technique allows the prediction of velocity and fluid shear stress within the designed 3D gradient scaffolds, which would be beneficial for the tissue scaffold development for interfacial tissue engineering in the future.The Charles M. Vest NAE Grand Challenges for Engineering International Scholarship is gratefully acknowledged. The author would like to thank Brunel Research Interdisciplinary Labs (BRIL) and Brief Award (BRIEF), and Royal Society Research Grant for supporting the research work and collaborations
Multi-tissue profiling of oxylipins reveal a conserved up-regulation of epoxide:diol ratio that associates with white adipose tissue inflammation and liver steatosis in obesity
Get PDFData sharing statement:
The individual-level data used in this study cannot be publicly shared due to ethical approval. Data set will be made available upon request through contact with the corresponding author. For sharing of data within a scientific collaboration any proposal should be directed to the corresponding author. Data will only be shared in accordance with legal frameworks, and when the integrity of the individual study participant can be guaranteed. This will be decided by the corresponding author on a case-by-case basis.Background:
Obesity drives maladaptive changes in the white adipose tissue (WAT) which can progressively cause insulin resistance, type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated liver disease (MASLD). Obesity-mediated loss of WAT homeostasis can trigger liver steatosis through dysregulated lipid pathways such as those related to polyunsaturated fatty acid (PUFA)-derived oxylipins. However, the exact relationship between oxylipins and metabolic syndrome remains elusive and cross-tissue dynamics of oxylipins are ill-defined.
Methods:
We quantified PUFA-related oxylipin species in the omental WAT, liver biopsies and plasma of 88 patients undergoing bariatric surgery (female N = 79) and 9 patients (female N = 4) undergoing upper gastrointestinal surgery, using UPLC-MS/MS. We integrated oxylipin abundance with WAT phenotypes (adipogenesis, adipocyte hypertrophy, macrophage infiltration, type I and VI collagen remodelling) and the severity of MASLD (steatosis, inflammation, fibrosis) quantified in each biopsy. The integrative analysis was subjected to (i) adjustment for known risk factors and, (ii) control for potential drug-effects through UPLC-MS/MS analysis of metformin-treated fat explants ex vivo.
Findings:
We reveal a generalized down-regulation of cytochrome P450 (CYP)-derived diols during obesity conserved between the WAT and plasma. Notably, epoxide:diol ratio, indicative of soluble epoxide hydrolyse (sEH) activity, increases with WAT inflammation/fibrosis, hepatic steatosis and T2DM. Increased 12,13-EpOME:DiHOME in WAT and liver is a marker of worsening metabolic syndrome in patients with obesity.
Interpretation:
These findings suggest a dampened sEH activity and a possible role of fatty acid diols during metabolic syndrome in major metabolic organs such as WAT and liver. They also have implications in view of the clinical trials based on sEH inhibition for metabolic syndrome.Wellcome Trust (PS3431_WMIH); Duke-NUS (Intramural Goh Cardiovascular Research Award (Duke-NUS-GCR/2022/0020); National Medical Research Council (OFLCG22may-0011); National Institute of Environmental Health Sciences (Z01 ES025034); NIHR Imperial Biomedical Research Centre
Search for W′ bosons decaying to a top and a bottom quark in leptonic final states in proton-proton collisions at = 13 TeV
Get PDFA preprint version of the article is available at arXiv:2310.19893v1 [hep-ex], https://arxiv.org/abs/2310.19893v1 . Comments: Submitted to the Journal of High Energy Physics. All figures and tables can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/B2G-20-012 (CMS Public Pages). Report number: CMS-B2G-20-012, CERN-EP-2023-213.A search for W' bosons decaying to a top and a bottom quark in final states including an electron or a muon is performed with the CMS detector at the LHC. The analyzed data correspond to an integrated luminosity of 138 fb^{-1} of proton-proton collisions at a center-of-mass energy of 13 Tev. Good agreement with the standard model expectation is observed and no evidence for the existence of the W' boson is found over the mass range examined. The largest observed deviation from the standard model expectation is found for a W' boson mass (mW′) hypothesis of 3.8 TeV with a relative decay width of 1%, with a local (global) significance of 2.6 (2.0) standard deviations. Upper limits on the production cross sections of W' bosons decaying to a top and a bottom quark are set. Left- and right-handed W' bosons with mW′ below 3.9 and 4.3 TeV, respectively, are excluded at the 95% confidence level, under the assumption that the new particle has a narrow decay width. Limits are also set for relative decay widths up to 30%. These are the most stringent limits to date on this W' boson decay channel.SCOAP3
The effect of task load, information reliability and interdependency on anticipation performance
Get PDFAvailability of data and materials:
Datasets and materials used are available from the corresponding author upon request.Supplementary Information is available online at: https://link.springer.com/article/10.1186/s41235-024-00548-8#Sec16 .In sport, coaches often explicitly provide athletes with stable contextual information related to opponent action preferences to enhance anticipation performance. This information can be dependent on, or independent of, dynamic contextual information that only emerges during the sequence of play (e.g. opponent positioning). The interdependency between contextual information sources, and the associated cognitive demands of integrating information sources during anticipation, has not yet been systematically examined. We used a temporal occlusion paradigm to alter the reliability of contextual and kinematic information during the early, mid- and final phases of a two-versus-two soccer anticipation task. A dual-task paradigm was incorporated to investigate the impact of task load on skilled soccer players’ ability to integrate information and update their judgements in each phase. Across conditions, participants received no contextual information (control) or stable contextual information (opponent preferences) that was dependent on, or independent of, dynamic contextual information (opponent positioning). As predicted, participants used reliable contextual and kinematic information to enhance anticipation. Further exploratory analysis suggested that increased task load detrimentally affected anticipation accuracy but only when both reliable contextual and kinematic information were available for integration in the final phase. This effect was observed irrespective of whether the stable contextual information was dependent on, or independent of, dynamic contextual information. Findings suggest that updating anticipatory judgements in the final phase of a sequence of play based on the integration of reliable contextual and kinematic information requires cognitive resources.No sources of funding from any funding agency in the public, commercial or not for profit sectors were used to assist in the preparation of this article
Analysis of Unicorn Theatre’s School Partnership Programme Evaluation
Get PDFThis report summarises the findings of Brunel University London’s analysis of Unicorn Theatre’s School Partnership Programme evaluation which was undertaken between September 2023 and January 2024. The Brunel project team worked in close collaboration with Unicorn to appraise its existing programme evaluation framework and tools to inform and develop its future evaluation processes
Navigating the currents of coastal narratives in search of sustainable futures
Get PDFData availability: There are no original data for archiving as this is a review paper.In the face of rapid, consequential changes in coastal conditions, coastal communities and regions must make decisions to address these changes and negotiate pathways towards more sustainable futures. Making just and equitable decisions requires engaging the affected population and influential stakeholders in the process. These processes can be improved by considering and engaging with shared narratives present across both time and location. This paper reviews exemplary instances in which narratives have been employed in facilitating decisions in coastal regions, in particular, future-facing-narratives that reflect the social landscape and dynamics operating in parallel with environmental and geographical conditions. Recognizing and learning from these narratives deepens and facilitates making informed, meaningful decisions on complex, contested, value-laden issues facing coastal communities. This paper argues that decisions at scales from local-to-national can be improved by considering shared narratives of sustainability and social identity as central pillars of the negotiation around both governance processes and desirable outcomes.SKP was supported by the Global Lives Research Centre, CBASS-BUL and BUL Impact Funding
The robot saw it coming: physical human interference, deservingness, and self-efficacy in service robot failures
Get PDFRobotic services’ popularity continues to increase due to technological advancements, labour shortages, and global crises. Yet, while providing these services, robots are subject to occasional physical interruption by humans to them, thus restricting their functioning and, at times, leading to failure. To investigate this issue, the present study examined the role of third-party human interference in service robot failures and its effects on the observers’ attitudes towards and willingness to engage with the robot. We manipulated human interference resulting in different robotic service failures in two online scenario-based experiments. The results revealed that individuals held less favourable attitudes towards a failed service robot without (vs. with) physical human interference, and they were less willing to engage with the failed service robot without (vs. with) physical human interference. The perceived deservingness of the robot accounted for this effect, moderated by the person’s self-efficacy regarding robots. The results are discussed with their implications for not only the theory of service failures and human-service robot interactions but also for robotic service providers
Performance of HDPE and Vacuum-Insulated Central Pipes for Coaxial Heat Exchangers in Geothermal Systems
Get PDFSpecial Session: Heat Transfer Processes in Geothermal Systems. Abstract number 109 (https://more.bham.ac.uk/ukhtc-2024/programme/).The thermal performance of a deep borehole coaxial heat exchanger with High-Density Polyethylene (HDPE) and vacuum-insulated central tubing (VIT) is presented in this paper. The analysis was performed for a wellbore equipped with a casing steel pipe of external diameter 198.52 mm and 10.36 mm thick. The central pipe consists of an HDPE tube 139.7 mm in outside diameter and 25.7 mm thick or two coaxial steel tubes, the first having an outside diameter of 139.7 mm and 10.5 mm thick, with the inner tube having an outside diameter of 101.6 mm and a thickness of 6.65 mm giving the same inner diameter of 88.3 mm as the HDPE tube. The gap between the steel pipes was maintained at different partial vacuum pressures. The depth was up to 5 km. Water was used as the working fluid. It was found that the VIT outperforms the HDPE for deep wells with the advantage diminishing for more shallow heat exchangers. A partial vacuum of 10 Pa does not demonstrate any relevant improvements over a gap maintained at normal atmospheric pressure, while the yield can be significantly improved when the pressure is reduced to 1 and 0.1 Pa.UKHTC202
Early-age GGBS concrete hydration temperature development and modelling
Get PDFThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonEarly-age hydration temperature development in concrete plays a crucial role in determining its structural performance and long-term durability. Excessive temperature rise and thermal gradients can induce stresses, leading to early-age cracking, particularly in mass concrete and large-span structures. The incorporation of Ground Granulated Blast Furnace Slag (GGBS) as a supplementary cementitious material helps mitigate these risks due to its lower heat of hydration compared to CEM I. However, knowledge gaps remain regarding the effects of variable ambient temperatures, the influence of coarse aggregates, and the applicability of existing hydration models developed for CEM I-only concrete. This study addresses these gaps through experimental investigations and numerical modelling.
The experimental program involved semi-adiabatic and isothermal calorimetry tests. Semi-adiabatic calorimetry tests on concrete specimens with varying GGBS replacement levels (0%–50%) assessed the impact of GGBS on hydration temperature development under uncontrolled conditions. Results demonstrated that increasing GGBS content reduced peak hydration temperatures and prolonged the induction period, confirming its thermal mitigation effect. Isothermal calorimetry tests were conducted on micro-concrete and equivalent mortar specimens at curing temperatures of 20, 30, 40, and 50°C to analyse hydration heat evolution. Higher curing temperatures accelerated early hydration but did not proportionally enhance long-term cumulative hydration heat. The presence of coarse aggregates slightly delayed hydration kinetics and increased cumulative hydration heat at later stages, though the observed differences were minimal, making it unclear whether they were due to experimental variability or an actual material effect.
A finite element model (FEM) was developed using COMSOL Multiphysics 6.1 to predict the early-age temperature development of in-situ concrete. The heat source for the model was derived from isothermal calorimetry data and adjusted using an Arrhenius-based equivalent age approach to reflect actual hydration heat evolution in concrete. The FEM was validated against semi-adiabatic calorimetry test results. The modelling results underscored the necessity of incorporating real-time ambient temperature variations, as constant-temperature boundary conditions led to discrepancies in predicted temperature profiles. Additionally, models using equivalent mortar hydration heat data overestimated peak temperatures, highlighting the importance of considering coarse aggregate effects.
The study also evaluated the applicability of the Three-Parameter Equation (TPE) hydration heat model, originally developed for CEM I, in predicting temperature development in GGBS-containing concrete. While the model provided reasonable accuracy, it consistently overestimated peak hydration temperatures for high-GGBS content mixes, likely due to its assumption of immediate GGBS hydration rather than its delayed activation. Refining hydration models to incorporate the two-stage reaction mechanism of GGBS could improve predictive accuracy.
Although this research enhances understanding of early-age concrete temperature development, certain limitations remain. The hydration heat differences between micro-concrete and equivalent mortar were small, making it difficult to determine whether the effect of coarse aggregates on hydration kinetics was genuine or within the range of experimental error. More advanced experimental techniques are required to clarify this issue. Additionally, the FEM was validated under laboratory-controlled conditions, necessitating future field-scale validation to account for real-world thermal interactions.
This study enhances the predictive capabilities of hydration temperature models by integrating experimental data with numerical simulations. The findings emphasize the importance of precise boundary condition inputs, improved hydration models for blended cement, and the necessity of incorporating micro-concrete data for accurate temperature predictions. Future research should focus on refining hydration models for GGBS-containing concrete, conducting field-scale validations, and integrating thermal stress analysis to further mitigate early-age cracking risks in concrete structures
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