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Scour reduction around bridge pier using the airfoil-shaped collar
Get PDFYesScouring around the bridge pier is a natural and complex phenomenon that results in bridge
failure. Failure of bridges have potential devastation and public safety and economic loss, which lead
to political consequences and environmental impacts. Therefore, it is essential to countermeasure the
scour around the bridge pier. This paper studies the effects of four different airfoil-shaped collars
(i.e., bc1 = 1.5b, bc2 = 2.0b, bc3 = 2.5b and bc4 = 3.0b, where bc and b are the diameter of the airfoil-shaped
collar and pier, respectively) as a scour countermeasure. All the experiments are conducted under
clear water conditions with uniform sediment and a constant water depth (y) of 10 cm. Airfoil-shaped
collar is placed at four elevations, i.e., bed level, y/4, y/2 and 3y/4 above the sediment bed level. It
is observed that the maximum percentages of scour reduction of 86, 100 and 100% occurred due to
protection provided by the collar bc2, bc3 and bc4, respectively, at sediment bed level. So, collars bc2,
bc3 and bc4 are efficient at the sediment bed level. The profiles of scour hole show that the length of
the transverse scour hole is greater than that of the longitudinal one. Numerical investigation of the
morphological changes in sediment bed and scour depth contours is developed using the FLOW-3D
for the pier with and without the airfoil-shaped collar
Detailed turbulent structures investigation around piers group induced flow
Get PDFYesThis paper aims to investigate the mean velocities and turbulence characteristics, which include Reynolds shear
stresses (RSS) and turbulent intensities, in order to study temporal and spatial flow patterns around a complex
three square-piers group. Measurements have been performed by acoustic Doppler velocimeter (ADV) to identify
turbulence flow structures alteration and vortices formation in longitudinal, transverse, and vertical directions.
In total, 164 locations around the bridge piers have been measured, while each location consists of no lesser than
15 vertical depth ADV data point measurements. To investigate the flow turbulence, critical locations have been
observed from high vortex-influenced regions. The impacted mean velocity profiles have been compared to that
at the unaffected region to study the flow alteration caused by piers group. The result reveals that the log-law
layer near wall has been enhanced by the installation of pier. Furthermore, as identified from the most critical locations of turbulent structures across different measurement rows, the accelerated flow will result in lower
observed turbulent structures. Although flow after each pier has been influenced by strong reversal velocities,
vortices have managed to form at near wake. Analysis has been divided into inner and outer flow regions (IFR
and OFR) based on flow depth to enhance the understanding of how bridge piers contribute to the development
of flow turbulence.Chinese National Natural Science Foundation (Grant No. 22308222) to this study
Deposition and microbial analyses from roof-top sediments within different sanitation environments
Get PDFYesSince the building roof acts as hub for atmospheric sediment deposition, the attached microbes can enter rainwater storage
tank with ease to cause health issue for rainwater users. This study aims to explore the trend of roof-top deposited microbes
in the different areas of Ikorodu local Government Area at Lagos, Nigeria. This paper also tests the hypothesis that the roof
sediment deposition being a significant source to home bacteria. The total deposition rate on the roof for 34 weeks, which
include 17 rainy and 17 dry weeks, were investigated. The enumerated bacteria was obtained from the roof deposit samples,
where four representative different sites have been analysed to study the solid depositions and microbes within the area
thoroughly. The sites were selected judging by their levels of sanitation and vegetation rate. The experimental investigations
showed that enumerated microbes and total suspended solid (TSS) depositions in the different areas were higher in the dry
season compared to rainy season, and the highest deposition was experienced in the Harmattan period. In addition, the results
showed that areas with poor drainage infrastructure and poor sanitation have the roof-top deposition with higher bacterial
count than good sanitation areas; while the unpaved and unvegetated areas produced higher deposits than the paved and
vegetated areas. In terms of contamination sources, this study has illustrated that the particulate deposition on the roof-top
prior to collection has further contaminated the roof-harvested rainwater
Geomorphological characteristics of Gandak river between Sahibganj and confluence with Ganga river during 1989-2022
Get PDFYesThe Gandak River originates in Nepal and merges with the Ganga River in India. The Gandak River is experiencing
significant geomorphological alterations due to climate change and anthropogenic causes. In this study, an attempt has
done to examine river bank erosion & accretion, shifting of the river bank, sinuosity, and braiding index of the Gandak
River between Sahibganj and the confluence with the Ganga River, covering a length of 92.4 km from 1989 to 2022 (33
years) using remote sensing and geospatial technologies. The delineation of the river bank line for different periods, along
with the quantification of erosion and accretion of the river’s right and left banks, were analysed using GIS, including
the sinuosity and braiding patterns. The overall sinuosity value ranged from 1.16 to 1.01 and did not follow any specific
pattern in significant reaches. The sinuosity value was almost constant over the most d/s reach of 30.74 km. The braiding
index of the River was found to be the maximum between Ismailpur and Baijalpur and the minimum value between
Munja and Chakia in 2015 and 1995 respectively. This study revealed that the river is shifting to the right, and bank
protection measures were needed. Finally, the proposed investigation revealed the braiding phenomenon, river shifting
in the transverse direction, and shifting of the meander bend was primarily responsible for the erosion and accretion of
the river banks. This study will benefit local government agencies, concerned authorities, and people residing along the
banks of the Gandak River by providing insights into the river’s migration patterns. Further, this knowledge aids in better
planning of riverbank protection measures and developing a navigation system
Association between nutrition self-efficacy, health locus of control and food choice motives in consumers in nine European countries
Get PDFYesWe investigated associations between food choice motives and psychological determinants of dietary health behaviour change (nutrition self-efficacy, NS-E, and health locus of control, HLoC) among 9381 participants (18–65 years, 49.4% females) from nine European countries. Price was the highest rated food choice motive. Higher importance of all motives was associated with higher NS-E and with higher Internal HLoC. Relationships between food choice motives and External HLoC were also in the expected direction in showing negative associations with Health, Natural Content, Weight Control, Mood and Sensory Appeal. Higher External HLoC was also associated with perceived greater importance of ‘external’ motives Ethical Concern, Familiarity and Convenience. Relationships between External HLoC and food choice motives were not all in the expected direction. Price was unrelated to External HLoC. Females rated the importance of all motives higher than males. People with less education ascribed greater importance to Price in motivating food choices. Together, these findings imply that self-efficacy and health locus of control should be considered along with motivations for food choice in dietary health promotion.European Union’s Seventh Frame work Programme for research, technological development and demonstration under Grant agreement n26549
The Impact of Firm-Level Political Risk on Eco-Innovation: The Moderating Effect of CEO Power
Get PDFYesThis study examines the impact of firm-level political risk on eco-innovation at the firm level, particularly emphasizing the moderating role of CEO power in this relationship. Using a dataset from 33 countries from 2006 to 2022, we employ two-step dynamic panel data estimations to address endogeneity concerns. The findings highlight a positive impact of political risk on eco-innovation, which is further strengthened in the presence of a powerful CEO. This evidence implies that effective leadership from CEOs can assist firms in navigating political risks and advancing sustainable initiatives. The results remain robust across various specifications, including alternative measurements for firm-level political risk. The study highlights the crucial role of CEOs in managing political risks and facilitating eco-innovative practices within firms
Emerging trends in the Circular Economy: Multidimensional perspective in the building sector
No full textYesThe study is grounded in the Triple Bottom Line theory, which emphasizes three dimensions of accountability: environmental, social, and economic. However, the research on which the study is based argues that developing
an effective framework for adopting the Circular Economy (CE) within the building sector requires a balanced consideration across four dimensions - environmental, social and economic, and technical - as the technical
dimension plays a crucial role in the advancement of the CE concept. This complements previous research into the understanding of the CE concept in the building sector, further investigating these key dimensions that
capture the evolution of CE research.
Focusing specifically on the building sector, the research conducted a robust literature review examining the environmental, social, economic, and technical aspects associated with the CE concept . The aim of this was to identify existing barriers and gaps that prevent the successful adoption of a CE in the building sector. Insights derived from the literature review will then serve as the foundation for a new and comprehensive circular framework appropriate for the building sector. The research and study together thus underscore the importance of a four-dimensional, balanced framework for effectively implementing CE principles within the building sector.The full-text of this article will be released for public view at the end of the publisher embargo, 12 months from first publication
The relationship between dietary and supplemental omega-3 highly unsaturated fatty acid intake, blood and tissue omega-3 highly unsaturated fatty acid concentrations, and colorectal polyp recurrence: A secondary analysis of the seAFOod polyp prevention trial
No full textYesBackground: The seAFOod randomised controlled trial tested colorectal polyp prevention by the omega-3 highly unsaturated fatty acid (HUFA) eicosapentaenoic acid (EPA) and aspirin. Variable dietary intake of omega-3 HUFAs (also including docosahexaenoic acid [DHA]) and differential EPA capsule compliance could confound analysis of trial outcomes.
Objective: To investigate the relationship between total (diet and capsule) daily omega-3 HUFA intake, red blood cell (RBC) and rectal mucosa omega-3 HUFA levels, and colorectal polyp outcomes in a secondary analysis of the seAFOod trial.
Methods: Individual-participant dietary omega-3 HUFA intake (mg/d) was derived from food frequency questionnaires using the EPIC-Norfolk fatty acid nutrient database. Capsule EPA intake (mg/d) was adjusted for compliance (capsule counting). Fatty acids were analysed by liquid chromatography-tandem mass spectrometry (as % of total fatty acids). HUFA oxidation was measured as the HUFA/saturated fatty acid (SAT) ratio. The colorectal polyp detection rate [PDR; % with one or more polyps] and polyp number per participant were analysed according to the change in RBC EPA level during the trial (ΔEPA), irrespective of treatment allocation.
Results: There was a small degree of HUFA degradation over time in RBC samples stored at higher than minus 80oC at research sites (r=-0.36, P+0.5% points (ΔEPAhigh), irrespective of allocation to EPA or placebo, had a lower PDR than ΔEPAlow individuals (odds ratio 0.63 (95% confidence interval [CI] 0.40,1.01) and reduced colorectal polyp number (incidence rate ratio 0.74 [95%CI 0.54,1.02]).
Conclusions: Analysis of the seAFOod trial according to the change in EPA level, instead of treatment allocation, revealed a protective effect of EPA treatment on colorectal polyp recurrence (ISRCTN05926847).This project (NIHR128210) was funded by the Efficacy and Mechanism Evaluation (EME) Programme, an MRC and NIHR partnership. AD and MAH were supported by Cancer Research UK grant C23434/A24939
A bi-level multi-node optimal siting, sizing, and operation of multi energy system in an integrated energy network of electricity-gas-heat with peer-to-peer trading
No full textYesMulti-energy system (MES) technologies, such as energy hubs, link energy networks like electricity, natural gas, and district heating networks. This interlinking enhances the interdependence and interaction of the networks. While the interlinking of the networks to form an integrated energy system (IES) can improve flexibility, there are challenges in coordinating the IES. As a result, the integration and synchronisation of energy flows become challenging, affecting the coordination and optimisation of the overall energy system. This paper presents a novel bi-level optimisation model for the optimal siting, sizing, and operation of MES within an IES encompassing electricity, gas, and heat with peer-to-peer (P2P) trading and demand response. The research addresses the strategic placement and sizing of interconnected energy hubs with various distributed energy resources (DER), including renewable energy sources (RES) and power-to-gas (P2G) systems, to enhance the efficiency and sustainability of the IES. The upper-level optimisation aims to minimise the energy hubs' total investment and operating costs, while the lower-level focuses on reducing the cost of energy imports from upstream networks and implementing demand response programs to balance supply and demand, considering the constraints of the IES. By utilising the Karush-Kuhn-Tucker (KKT) optimality conditions and the big-M method, the bi-level problem is converted into a single-level Mixed-Integer Linear Programming (MILP) problem. The proposed model and methodology are validated through case studies on an integrated energy network based on the 16-bus 33 kV UK generic distribution system, a 20-node gas network and a 30-node heat network, demonstrating their effectiveness in the IES. The research demonstrates that coupled energy networks are viable for creating efficient and flexible IES. The strategic scheduling of energy hubs, equipped with generation equipment such as RES, storage, P2G and other conversion technologies operating within the IES with P2P energy trading, not only meets diverse energy demands but also enhances the sustainability and economic viability of the energy system.The full-text of this article will be released to public view at the end of the publisher embargo on 31 Dec 2026
