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Additive Manufacturing as a Technique to Develop Multipart Assemblies in Computer Based Design Methods
No full textDesigning for manufacturability and multipart assemblies using an additive manufacturing process of choice is an exciting arena. Brunel Design School uses 3D printing in their computer-based design methods module to print 3 dimensional multipart models of students work. The module aims to allow students to appreciate the place of computer aided design, analysis and manufacturing methods in a range of design activities. The methods of model generation are aimed to allow students to develop, evaluate, and select appropriate design techniques and tools for product design engineering. The module enables students to integrate a wide range of digital manufacturing techniques to aid their processes while using the latest 3d printing capabilities to produce high quality multipart assemblies
Persistence in real GDP: evidence from Europe and the US
No full textJEL classification: C22, E23.This note provides extensive evidence on the persistence properties of real GDP in 17 European countries and in the US over the period 1960-2023 using a fractional integration framework. The analysis suggests that in all cases shocks have permanent effects on the level of real GDP. This is consistent with the idea that it is the growth rate of output which is stationary and fluctuates around a long-run equilibrium level. Further, the degree of persistence varies across countries, with the US, Greece and Spain exhibiting the highest one and Sweden and Ireland the lowest. Policy makers should take such properties into account when formulating appropriate stabilisation policies.Prof. Luis A. Gil-Alana gratefully acknowledges financial support from the project from ‘Ministerium de Economía, Industria y Competitividad' (MINEIC), `Agencia Estatal de Investigación' (AEI) Spain and `Fondo Europeo de Desarrollo Regional' (FEDER), Grant D2023149516NB-I00 funded by MCIN/AEI/ 10.13039/501100011033. He also acknowledges support from an internal Project of the Universidad Francisco de Vitoria
Rapid aerodynamic approximation of rotating blades using AI and automation logic
Get PDFThe aerodynamic performance of rotorcraft blades critically impacts rotor system efficiency, directly influencing lift, fuel consumption, and aircraft endurance. Conventional fixed-blade designs constrain aerodynamic optimisation across varying flight conditions. Refining techniques applied to rotational aerodynamics presents significant challenges: (a) high complexity, (b) time consumption, and (c) susceptibility to errors. In parallel with advances in non-conventional rotor blade designs, artificial intelligence (AI) has emerged as a transformative technology in aerodynamic modelling, offering enhanced computational capabilities and efficiency. This paper demonstrates how integrating AI-driven aerodynamic modelling facilitates rapid approximation of performance parameters. Specifically, the study addresses three objectives: 1) streamlining methodology while maintaining accuracy, 2) substantially reducing calculation time, and 3) minimising or eliminating errors in manual processing. A Python-based Automation Logic (PAL) algorithm is employed to automate estimation of aerodynamic parameters, reducing reliance on iterative, labour-intensive techniques. Processing time decreased from approximately 200 hours to under 7; a 97% reduction, while preserving computational fidelity and eliminating the ~1.4% rounding error found in manual integration. The findings underscore the transformative potential of AI-driven methodologies in rotorcraft aerodynamics, enabling faster, more reliable, and computationally efficient analyses. Ultimately, the study illustrates how accuracy, speed, and innovation can coexist rather than be mutually exclusive
Designing an optimised hinged Magnetic Flux Leakage (MFL) system for remote localised defect monitoring in tank floors and pipelines
Get PDFThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonA significant demand exists for magnetic flux leakage (MFL) systems designed for permanent installation in difficult-to-access areas, such as pipe elbows, where localised corrosion occurrences are prevalent. These systems enable continuous and long-term remote monitoring. Designing a magnetic circuit is a critical stage in MFL development, ensuring that induced magnetisation intensity and uniform flux distribution are maintained to facilitate effective defect detection. This work aims to develop a novel optimal-performance and compact MFL system that can be used to inspect a wide range of inspection components, such as flat plates and pipes, including pipe elbows.
This research was based on a simulation-led design of an MFL circuit using finite element analysis (FEA) and optimisation algorithms, and an experimental programme to verify and validate the developed designs. Analyses and optimisation of the magnetic circuit were performed by parametric study of a reference configuration, followed by optimisation of multiple magnetic circuit parameters, resulting in the identification of alternative solutions.
Three magnetic circuit types were developed: a reference (Ref) circuit with improved design parameters, a novel hinged (Hin) based circuit and a novel optimised (Opt) circuit. Using a comprehensive simulation program, the MFL reference configuration underwent a detailed parametric study based on sensitivity analysis of the circuit components. This led to an improved Ref circuit, considering the specified sample magnetisation level, recommended operation points on the B-H curve, and improved uniformity of magnetic flux density within the sample. The next step in the design process was the development of a new magnetic circuit with a hinged magnet bridge, which allowed for improved MFL application on non-flat inspection surfaces, e.g. pipes and elbows. Out of the four hinged configurations, the most suitable was adopted for further parameter and topology optimisations using Bound Optimisation by Quadratic Approximation (BOBYQA) and Method of Moving Asymptotes (MMA) algorithms.
The simulation-based design was validated experimentally for all three (Ref, Hin and Opt) circuits by characterising machined cylindrical imperfections on three object shapes: flat plates, pipe and pipe elbow. The Opt circuit demonstrated the best performance, is more compact and can be used for a range of inspection object shapes, including plates, pipes and elbows. The discrepancy between experimental and simulation results was below 2% for all tests. The sensitivity analysis of the novel devices was performed for defects of different depths, radii, locations and sensor lift-offs.Lloyd's Register Foundation / NSIR
Ambient IoT Connectivity Topologies: Technology Enablers, Applications, and Challenges
Get PDFSustainability and energy efficiency are anticipated to be foundational goals of sixth-generation (6G) networks, motivating the development of ultra-low-power communication solutions. The emerging concept of ambient Internet of things (A-IoT), currently under study by the third generation partnership project (3GPP), aims to enable ultra-low-power, battery-free connectivity over cellular networks to support the massive deployment of Internet of things (IoT) devices. Leveraging backscatter communication as a key enabler, A-IoT introduces a new class of devices designed to operate at ultra-low power levels, making it a promising candidate for sustainable 6G applications. In this article, we investigate the connectivity topologies of A-IoT based on backscatter communication. We analyze the enabling technologies in the context of each topology, highlighting how deployment constraints influence their design and feasibility. A comparative performance evaluation is presented, with an emphasis on the outage probability across the different topologies. Furthermore, we explore a range of applications specific to each topology and provide insights into practical challenges, alongside prospective solutions
Who gets in? a conjoint analysis of labour market demand and immigration preferences in England and Japan
Get PDFSupplemental Material is available online at: https://www.tandfonline.com/doi/full/10.1080/1369183X.2025.2545432# .We advance research on attitudes towards immigration using an experimental design that more clearly separates between skill level and labour market demand. In single profile conjoint design experiments fielded in England and Japan, we replicate the well-established finding that high-skill immigrants are generally preferred to low-skill immigrants. However, we also show a more nuanced result in that labour market demand – regardless of skill level – is also important. Indeed, in both England and Japan, the public is willing to accept low-skill workers in high-demand occupations at levels at least as much as for high-skill but low-demand occupations. Labour market demand is an important factor in understanding attitudes towards economic migration.This research was supported by a joint grant from the Economic and Social Research Council of the UK and the Japan Society for the Promotion of Science, grants ES/W011913/1 and JPJSRP 20211704, respectively
How does channel pattern generate unsteady bedload transport?
Get PDFAbstract presented at the EGU General Assembly 2025, Vienna, Austria and online, Session GM10.1: Fluvial systems: dynamics and interactions across scales.
Convener: Eliisa Lotsari | Co-conveners: Joshua Ahmed, László Bertalan, Sumit Das.
Orals | Thu, 01 May, 08:30–10:15 (CEST), 14:00–18:00 (CEST).
Posters on site | Attendance Wed, 30 Apr, 10:45–12:30 (CEST) | Display Wed, 30 Apr, 08:30–12:30.Unsteady bedload transport, whereby temporal variations in transport rate occur under constant total discharge and sediment supply, can be generated from interactions between hydraulics, sediment sorting, bedforms and reach-scale morphological variability. At larger scales, the relation between temporal and spatial variability in bedload transport has not been explicitly resolved largely due to the difficulty in obtaining coincident data over large areas and for long time periods. We hypothesise that spatial variability in bedload transport is a function of river pattern, and explore the implications of our results for temporal bedload variability. We combined bathymetric and LiDAR surveys to generate a high-resolution DEM of a 33km reach of the Bislak River, the Philippines. This DEM was then used for two-dimensional hydraulic modelling to predict distributions of flow and shear stress across the entire reach. The reach consists of four contiguous sub-reaches with different (meandering, wandering, braided, and deltaic) channel patterns. Probability distributions of shear stress and predicted bedload transport rates within each sub-reach reveal significant differences between the four channel patterns. From these results, we assess how different channel patterns generate distinct bedload signatures that can be propagated to predict synthetic time series of bedload transport. The properties of these time series are compared with empirical data on the scales of unsteady bedload transport. Improved understanding of bedload transport variability has implications for quantitative definitions of channel pattern, interpretations of alluvial deposits and assessments of channel response to anthropogenic modification
Energy-scaling behavior of intrinsic transverse-momentum parameters in Drell-Yan simulation
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Release and preservation of data used by the CMS Collaboration as the basis for publications is guided by the CMS data preservation, re-use, and open access policy https://dx.doi.org/10.7483/OPENDATA.CMS.7347.JDWH .A preprint version of the article is available on arXiv, arXiv:2409.17770v2 [hep-ph] (https://arxiv.org/abs/2409.17770). [v2] Tue, 8 Apr 2025 23:23:48 UTC (450 KB). Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/GEN-22-001 (CMS Public Pages).
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Experiment (hep-ex).
Report numbers: CMS-GEN-22-001, CERN-EP-2024-216An analysis is presented based on models of the intrinsic transverse momentum (intrinsic ) of partons in nucleons by studying the dilepton transverse momentum in Drell-Yan events. Using parameter tuning in event generators and existing data from fixed-target experiments and from hadron colliders, our investigation spans 3 orders of magnitude in center-of-mass energy and 2 orders of magnitude in dilepton invariant mass. The results show an energy-scaling behavior of the intrinsic parameters, independent of the dilepton invariant mass at a given center-of-mass energy.We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid and other centers for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC, the CMS detector, and the supporting computing infrastructure provided by the following funding agencies: SC (Armenia), BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES and BNSF (Bulgaria); CERN; CAS, MoST, and NSFC (China); MINCIENCIAS (Colombia); MSES and CSF (Croatia); RIF (Cyprus); SENESCYT (Ecuador); ERC PRG, RVTT3 and MoER TK202 (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); SRNSF (Georgia); BMBF, DFG, and HGF (Germany); GSRI (Greece); NKFIH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LMTLT (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MES and NSC (Poland); FCT (Portugal); MESTD (Serbia); MCIN/AEI and PCTI (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); MHESI and NSTDA (Thailand); TUBITAK and TENMAK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA)
Childhood predictors of adults’ belief in god, gods, and spiritual forces across 22 countries
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All analyses were pre-registered with COS prior to data access, with only slight subsequent modification in the regression analyses due to multicollinearity (https://osf.io/mgv6k); all code to reproduce analyses are openly available in an online repository as described in Johnson, B. R. et al. "The Global Flourishing Study" https://doi.org/https://doi.org/10.17605/OSF.IO/3JTZ8 (2024). The data are publicly available through the Center for Open Science (https://www.cos.io/gfs).Supplementary Information is available online at: https://www.nature.com/articles/s41598-025-98796-1#Sec16 .The Global Flourishing Study – Wave I collection is available online at: https://www.nature.com/collections/eaeicjffaf .Religion is an integral part of everyday life for billions of people, yet little is known about the developmental antecedents of religious belief outside of Western cultures. Using data from over 200,000 individuals across 22 countries, we evaluate several childhood predictors of belief in God, gods, and spiritual forces (Belief in God) in adulthood. We hypothesized that these childhood experiences, personal attributes, and familial or social circumstances would have meaningful and varied associations with Belief in God as adults, with the strength of these associations differing by country, reflecting diverse cultural influences. Most candidate predictors (e.g., parental marital status, childhood socioeconomic status, abuse, being an outsider, and immigration) were associated with Belief in God in some countries but with substantial variation. However, when pooled across countries, only childhood religious service attendance, birth cohort, and gender were significant predictors. Yet there was important variation even for these predictors, and no predictor had a consistent association across all countries. Though this cross-sectional design is limited in allowing causal inference, results provide insights into early-life experiences that might contribute to adults’ Belief in God. The heterogeneity of results highlights the importance of considering any childhood predictor within its social and cultural context.John Templeton Foundation, Templeton World Charity Foundation, Templeton Religion Trust, Fetzer Institute, David & Carol Myers Foundation, Paul Foster Family Foundation, Well-Being for Planet Earth, Well Being Trust
Optimization of the low-load performance and emission characteristics for a heavy-duty diesel engine fueled with diesel/methanol by RSM-NSWOA
No full textIn this paper, the renewable energy, methanol, used as alternative fuel for diesel engine was systematically investigated under low load. The effect of different methanol fractions (MF) on diesel-methanol dual-fuel (DMDF) combustion, emission and performance is explored. Results shows that the net indicated efficiency (NIE) of DMDF is 2.4 % higher than that of conventional diesel combustion (CDC) when the MF increased to 60 %, although the combustion efficiency is decreased. The higher MF can also produce less NOX and smoke with higher HC and CO emissions. Then, exhaust gas recirculation (EGR) was added to further optimize the DMDF operation under MF of 60 %. A comparison analysis shows that the DMDF with 26 % EGR improve the NIE and NOX emission by 3.5 % and 87 %, respectively compared to CDC. Finally, the NOX, BSFC and combustion efficiency of DMDF were further optimized based on response surface method (RSM) and non-dominated sorting whale optimization algorithm (NSWOA). It is found that there is a strong trade-off among them. In order to obtain lower NOX emissions and BSFC simultaneously, the combustion efficiency has to be compromised. Finally, the NOX and BSFC of optimized DMDF are reduced by 53.42 %, 5.37 % respectively when compared to the previous experimental results.This work is supported by the National Natural Science Foundation of China (22302044, 22172038), and the Guangxi Science and Technology Major Program (AA24263077)
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