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Flow characteristics in partially vegetated channel with homogeneous and heterogeneous layouts
No full textYesThis study presents the experimental results of the flow characteristics, such as the flow adjustment, velocity profiles, mixing layer, and the momentum exchange, in the partially vegetated channel with homogeneous and heterogeneous layouts. Three cases are considered, including two homogeneous canopies with uniform sparse and dense vegetation patches respectively, and a heterogeneous canopy consisting of alternating patches of both densities. Results show that heterogeneous canopy requires a longer adjustment distance to reach the quasi-equilibrium region, compared with the homogenous canopy of the same density. In heterogeneous canopy flow, the mixing layer width and the momentum thickness fluctuates with the alternation of vegetation density. The increased values for these two parameters compared to those values for the homogeneous canopies indicate that the greater resistance and momentum loss occur for the heterogeneous layout. A wavy region of the enhanced in-plane turbulence kinetic energy (TKE) is observed in the heterogeneous canopy, suggesting a comparatively more chaotic flow condition, whereas the contours of in-plane TKE are smooth in homogeneous canopies. The presence of the coherent structures in heterogeneous canopy is identified by spectral analysis and the quasi-periodic fluctuations of velocities. The Reynolds stress associated with the coherent structures is found to be the dominator of the contribution to the total Reynolds stress. The comparison between the homogenous canopies of different density is also conducted. These results will be of practical importance for the design of vegetation layouts in water ecological restoration projects and for river management.National Natural Science Foundation of China (grant numbers 52020105006 and 11872285) and the Open Funding of State Key Laboratory of Water Resources and Hydropower Engineering Science (WRHES), Wuhan University (Project number 2018HLG01
A Proposed IoT Architecture for Effective Energy Management in Smart Microgrids
No full textYesThe current electricity grid suffers from numerous challenges due to the lack of an effective energy management strategy that is able to match the generated power to the load demand. This problem becomes more pronounced with microgrids, where the variability of the load is obvious and the generation is mostly coming from renewables, as it depends on the usage of distributed energy sources. Building a smart microgrid would be much more economically feasible than converting the large electricity grid into a smart grid, as it would require huge investments in replacing legacy equipment with smart equipment. In this paper, application of Internet of Things (IoT) technology in different parts of the microgrid is carried out to achieve an effective IoT architecture in addition to proposing the Internet-of-Asset (IoA) concept that will be able to convert any legacy asset into a smart IoT-ready one. This will allow the effective connection of all assets to a cloud-based IoT. The role of which is to perform computations and big data analysis on the collected data from across the smart microgrid to send effective energy management and control commands to different controllers. Then the IoT cloud will send control actions to solve microgrid's technical issues such as solving energy mismatch problem by setting prediction models, increasing power quality by the effective commitment of DERs and eliminating load shedding by turning off only unnecessary loads so consumers won't suffer from power outages. The benefits of using IoT on various parts within the microgrid are also addressed
Experimental observation of turbulent structure at region surrounding the mid-channel braid bar
No full textNoRiver morphological processes are among the most complex and least understood phenomenon in nature. Recent research indicates that the braiding of marine waterways of the estuary zone occurs at an aspect ratio similar to the alluvial braided river. The instability of complex sporadic fluvial processes at river-sea interface is responsible for bar formation in alluvial as well as in marine waterbodies Due to the lack of knowledge of flow characteristics around bar, the flow structure around the sand bar is analyzed. The bursting events play the crucial role in understanding the fluvial characteristics in the vicinity of submerged structure. The study of bursting events around the mid-channel bar is only done by the present author. The effect of submergence ratio on the turbulence behavior in the proximity of bar is analyzed in this study. The flow turbulence generated by the mid-channel bar is also analyzed in detail. The extreme turbulent burst is segregated from low intensity turbulent events by using the hole size concept. The effect of hole size on the parameter Dominance Function is analysed which is not yet studied by any researcher for mid-channel bar. The Momentum Dominance Function (MDF) parameter increases with increase in the Hole Size. This indicates that the magnitude of upward flux increases with increase in the hole size. The effect of bar height on the turbulent burst which is not yet studied by any researchers is analyzed in the present research. The joint probability distribution of bursting events is modeled using the Gram-Charlier bivariate joint probability function. The joint probability distribution gives the details of probabilistic structure of flow in the vicinity of bar. The effect of bar is predominant only in the lower flow layer. The joint probability distribution graph becomes more eccentric toward the dominant quadrants with increase in the submergence ratio. This indicates that the probability of dominant events further increases with increase in the submergence ratio
Design, Synthesis, Biological Evaluation and In Silico Study of Benzyloxybenzaldehyde Derivatives as Selective ALDH1A3 Inhibitors
No full textYesAldehyde dehydrogenase 1A3 (ALDH1A3) has recently gained attention from researchers in the cancer field. Several studies have reported ALDH1A3 overexpression in different cancer types, which has been found to correlate with poor treatment recovery. Therefore, finding selective inhibitors against ALDH1A3 could result in new treatment options for cancer treatment. In this study, ALDH1A3-selective candidates were designed based on the physiological substrate resemblance, synthesized and investigated for ALDH1A1, ALDH1A3 and ALDH3A1 selectivity and cytotoxicity using ALDH-positive A549 and ALDH-negative H1299 cells. Two compounds (ABMM-15 and ABMM-16), with a benzyloxybenzaldehyde scaffold, were found to be the most potent and selective inhibitors for ALDH1A3, with IC50 values of 0.23 and 1.29 µM, respectively. The results also show no significant cytotoxicity for ABMM-15 and ABMM-16 on either cell line. However, a few other candidates (ABMM-6, ABMM-24, ABMM-32) showed considerable cytotoxicity on H1299 cells, when compared to A549 cells, with IC50 values of 14.0, 13.7 and 13.0 µM, respectively. The computational study supported the experimental results and suggested a good binding for ABMM-15 and ABMM-16 to the ALDH1A3 isoform. From the obtained results, it can be concluded that benzyloxybenzaldehyde might be considered a promising scaffold for further drug discovery aimed at exploiting ALDH1A3 for therapeutic intervention
Computational Face Recognition Using Machine Learning Models
Get PDFFaces are among the most complex stimuli that the human visual system
processes. Growing commercial interest in face recognition is encouraging, but it
also turns out to be a challenging endeavour. These challenges arise when the
situations are complex and cause varied facial appearance due to e.g., occlusion,
low-resolution, and ageing. The problem of computer-based face recognition
using partial facial data is still largely an unexplored area of research and how
does computer interpret various parts of the face. Another challenge is age
progression and regression, which is considered to be the most revealing topic
for understanding the human face changes during life.
In this research, the various computational face recognition models are
investigated to overcome the challenges posed by ageing and occlusions/partial
faces. For partial face-based face recognition, a pre-trained VGGF model is
employed for feature extraction and then followed by popular classifiers such as
SVMs and Cosine Similarity CS for classification. In this framework, parts of faces
such as eyes, nose, forehead, are used individually for training and testing. The
results showing that there is an improvement in recognition in small parts, such
as recognition rate in forehead enhanced form about 0% to nearly 35%, eyes
from about 22% to approximately 65%. In the second framework, five sub-models
were built based on Convolutional Neural Networks (CNNs) and those models
are named Eyes-CNNs, Nose-CNNs, Mouth-CNNs, Forehead-CNNs, and
combined EyesNose-CNNs. The experimental results illustrate a high recognition
rate when it comes to small parts, for example, eyes increased up to about
90.83% and forehead reached about 44.5%. Furthermore, the challenge of face
ageing is also approached by proposing an age-template based framework,
generating an age-based face template for enhanced face generation and
recognition. The results showing that generated new aged faces are more reliable
comparing with state-of-the-art
How Can International Institutions Be Improved to Ensure Accountability and Justice for Violations That Occur in Humanitarian and Counter-Terrorism Operations?
Get PDFThe thesis purports to assess the United Nations Security Council (UNSC) in
maintaining international peace and security and the International Criminal
Court (ICC) in prosecuting individuals who have committed severe violations
of international humanitarian law (IHL) and international law, during
humanitarian and counter-terrorism operations. The thesis endeavours to
highlight the failures of both institutions, firstly, the UNSC being unable to fulfil
its institutional mandate, which is mainly attributed to the abuse of veto
privileges granted to the five permanent members (P5). This has effectively
allowed individuals from the militaries of the P5 and their allies elude criminal
liability, promoting a culture of impunity. The UNSC’s failure to prevent P5
members use of unauthorised military force in pursuing counter-terrorism
operations and interpose expeditiously in humanitarian crises, have also
contributed to the erosion of the institutions’ legitimacy, which is further
perpetuated by the USA’s continued ‘War on Terror’ doctrine after the 9/11 terrorist attacks. Secondly, the ICC’s inability to prosecute individuals for crimes under the Rome Statute will also be highlighted as the principle of complementarity and the court’s inability to enforce arrest warrants are
significant factors contributing to the institutions inability to administer
international criminal justice. The thesis draws upon practical examples to
substantiate the failures of both institutions by referring to the conflicts in:
Afghanistan, Iraq, Palestine, Syria and Libya. Before concluding the UNSC
and the ICC have become futile, the thesis will then make recommendations for reform and propose a novel solution to restore legitimacy back to both institutions
Analysis and pattern mapping of organic interfaces by means of seismic geophysical technologies to investigate archaeological palaeolandscapes beneath the Southern North Sea
Get PDFInvestigating the archaeology of submerged landscapes beneath many
metres of sea and buried under modern sands requires an understanding
of the terrestrial surface as it may have been prior to the inundation. To do
this, environmental evidence is required from contextualised in-situ
locations and the best material evidence for preservation of archaeology,
organic remains, dating proxies, pollen, diatoms, microfossils, coleoptera
etc. is peat.
This research supports the search for peat in submarine environments by
interpreting seismic surveys of the sub-sea floor and analysing reflective
signals for distinctive organic responses. By means of sedimental analysis
and ground observation, the research sets out to differentiate between
organic signals, to allow for the identification and location of shallow peat
beds within features of a palaeolandscape. Using these results should
provide an opportunity to target such peat beds in an archaeologically
focused coring programme.
The research also examines ways in which organic responses may be
mapped over larger areas in order to integrate the results into a wider
scale landscape model identifying potential peatland, marsh, valley fen
and lowland areas.
Finally, the research introduces an artificial intelligence neural networking
technology for the identification of organic interfaces in seismic surveys,
examining three different ways in which this could be accomplished using
specialist computer tools and software
An integrated approach for the investigation and analysis of signalling networks in azoospermia. Biological network analysis for the discovery of intracellular signalling pathway alterations associated with azoospermia.
No full textThe full text of the thesis is currently restricted.The full text will be available at the end of the embargo period: 1st Nov 202
Investigating the factors affecting the net benefits and change in user behaviour in technology push scenarios in Smart cities
Get PDFPurpose – The aim of this study is to investigate the factors affecting the net benefits
and change in user behaviour in a technology push scenario in Smart Cities.
Design/methodology/approach –The research was conducted using a quantitative
approach. Hence, quantitative data was obtained by devising and distributing a
questionnaire adapted from the literature to serve the purpose of this research. Data
was analysed by using SmartPLS software, since this tool allowed for the creation of
a Structural Equation Modelling (SEM).
Contributions –The research is expected to help foster an understanding of the
factors affecting citizens’ satisfaction with technology-supporting smart cities. The
focus of this research was on the scenario where technology was introduced by the
government to support the development of smart cities, and where citizens ‘do not
have a choice’ and are ‘pushed’ to use them. The research contributes a model for
assessing the role of satisfaction in enhancing the net benefits of smart city
technologies on the lives of citizens, as well as the change in individuals’ behaviour
towards smart city technologies when they are ‘pushed’ for use. The findings provided
insights to enable policy makers to implement smart cities in developing countries
while ensuring the satisfaction of the users.
Originality/value – The originality of this research is centred around determining how
satisfied citizens are with smart cities and the net benefit of smart cities within a
developing country (Kuwait) context. The research is also unique in that it examines
the role of citizens’ satisfaction in changing their behaviour towards ‘push’ technology
within smart cities.
Theoretical Contributions – This study examined the factors that led to acceptance
of smart cities in Kuwait. Hence, this study used the theories related to user
acceptance of technology and added to its trust in provider. Previous studies have
examined trust as a broad concept. Moreover, this study incorporated the push theory
and also examined the change in user behavior, which was not examined in earlier
studies
Luminal Bioavailability of Orally Administered ω-3 PUFAs in the Distal Small Intestine, and Associated Changes to the Ileal Microbiome, in Humans with a Temporary Ileostomy
Get PDFYesBackground: Oral administration of purified omega-3 (ω-3) PUFAs is associated with changes to the fecal microbiome. However, it is not known whether this effect is associated with increased PUFA concentrations in the gut.
Objectives: We investigated the luminal bioavailability of oral ω-3 PUFAs (daily dose 1 g EPA and 1g DHA free fatty acid equivalents as triglycerides in soft-gel capsules, twice daily) and changes to the gut microbiome, in the ileum.
Methods: Ileostomy fluid (IF) and blood were obtained at baseline, after first capsule dosing (median 2 h), and at a similar time after final dosing on day 28, in 11 individuals (median age 63 y) with a temporary ileostomy. Fatty acids were measured by LC–tandem MS. The ileal microbiome was characterized by 16S rRNA PCR and Illumina sequencing.
Results: There was a mean 6.0 ± 9.8-fold and 6.6 ± 9.6-fold increase in ileal EPA and DHA concentrations (primary outcome), respectively, at 28 d, which was associated with increased RBC ω-3 PUFA content (P ≤ 0.05). The first oral dose did not increase the ileal ω-3 PUFA concentration except in 4 individuals, who displayed high luminal EPA and DHA concentrations, which reduced to concentrations similar to the overall study population at day 28, suggesting physiological adaptation. Bacteroides, Clostridium, and Streptococcus were abundant bacterial genera in the ileum. Ileal microbiome variability over time and between individuals was large, with no consistent change associated with acute ω-3
PUFA dosing. However, high concentrations of EPA and DHA in IF on day 28 were associated with higher abundance of Bacteroides (r2 > 0.86, P 0.94, P < 0.05).
Conclusions: Oral administration of ω-3 PUFAs leads to increased luminal ω-3 PUFA concentrations and changes to the microbiome, in the ileum of individuals with a temporary ileostomy