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Design and Simulation of a Blowdown Facility for Supercritical Carbon Dioxide
Get PDFThis paper describes an experimental blowdown facility designed to characterise the expansion of supercritical CO2 near the critical point. Specifically, the test rig aims at replicating the expansion process at the leading edge of a CO2 compressor with the goal of studying the role of real-gas effects, and possible condensation. The test rig consists of two pressure vessels (high and low pressure), a reciprocating compressor used for charging, a temperature-controlled water circuit to adjust the temperature of the high-pressure tank and a test section comprised of a convergent-divergent nozzle.
The specification of the pressure vessels and the recharging compressor is described which are selected to allow for reasonable charging and blowdown times. The design of a thermal management system is also described that keeps the conditions within the high-pressure vessel temperature within the desired range, whilst avoiding over pressurisation. The optimisation of the test rig layout is also discussed which includes identifying an economically and technically viable solution for the positioning of pressure relief valves and the ventilation system. Furthermore, the range of anticipated test conditions that can be achieved and the expected expansion process within the nozzle have been explored using transient lumped mass models of pressure vessels that are coupled with a quasi-steady nozzle model to determine the expected conditions within the nozzle. The nozzle model assumes a homogeneous mixture under thermal equilibrium at any point where the working fluid enters the saturation dome.
For the defined test rig specifications (high pressure tank = 0.1 m3; low pressure tank = 0.185 m3; CO2 charge = 100 kg; nozzle throat = 100 mm2) it is predicated that constant inlet pressure conditions can be sustained for between 0.4 and 5.5 seconds for test section inlet conditions ranging between 27 and 45 °C, and 70 and 90 bar.The funding for this research has been provided by the Engineering and Physical Sciences Research Council (EPSRC) in the UK under research grant EP/V001752/1 (SCOtWoHR)
Editorial to the EGOV-CeDEM-part 2024 CEUR proceedings
Get PDFGOV-CeDEM-ePart-Ongoing 2024
Ongoing Research, Practitioners, Posters, Workshops, and Projects at EGOV-CeDEM-ePart 2024
Proceedings of Ongoing Research, Practitioners, Posters, Workshops, and Projects of the International Conference EGOV-CeDEM-ePart 2024
Ghent University and KU Leuven, Ghent/Leuven, Belgium, September 1-5, 2024.Summary: There were 83 papers submitted for peer-review to this workshop. Out of these, 56 papers were accepted for this volume, 34 as regular papers, 9 as short papers, 10 as posters and 3 as an extended abstract
Enriching the physics program of the CMS experiment via data scouting and data parking
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Release and preservation of data used by the CMS Collaboration as the basis for publications is guided by the https://cms-docdb.cern.ch/cgi-bin/PublicDocDB/RetrieveFile?docid=6032&filename=CMSDataPolicyV1.2.pdf&version=2 CMS data preservation, re-use and open access policy.A version of the published article is available at arXiv:2403.16134v2 [hep-ex], https://arxiv.org/abs/2403.16134v2 . 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/EXO-23-007 (CMS Public Pages) Report number: CMS-EXO-23-007, CERN-EP-2024-068. Journal reference: Phys. Rept. 1115 (2025) 678. Submission history: From: The CMS Collaboration: [v2] Fri, 11 Apr 2025 16:24:50 UTC (5,788 KB)Specialized data-taking and data-processing techniques were introduced by the CMS experiment in Run 1 of the CERN LHC to enhance the sensitivity of searches for new physics and the precision of standard model measurements. These techniques, termed data scouting and data parking, extend the data-taking capabilities of CMS beyond the original design specifications. The novel data-scouting strategy trades complete event information for higher event rates, while keeping the data bandwidth within limits. Data parking involves storing a large amount of raw detector data collected by algorithms with low trigger thresholds to be processed when sufficient computational power is available to handle such data. The research program of the CMS Collaboration is greatly expanded with these techniques. The implementation, performance, and physics results obtained with data scouting and data parking in CMS over the last decade are discussed in this Report, along with new developments aimed at further improving low-mass physics sensitivity over the next years of data taking.SCOAP3
Thermodynamic simulation and exergy analysis of a hydrogen SI engine
Get PDFThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonConcerns of limited fossil fuel reserves, environmental pollution from their extraction,
processing, and use, and health effects from localised tailpipe emissions are leading to a
transition of the transportation sector towards low-carbon and carbon-free alternative fuels
for internal combustion engines. As an alternative fuel hydrogen has the potential to
significantly reduce tailpipe greenhouse gas emissions, and offers advantages in terms of
its combustion properties. To understand hydrogen combustion in an internal combustion
engine and the upper limit of efficiency, single- and two-zone combustion models exploiting
the second law of thermodynamics are developed to assess the origins of the exergy losses.
The single-zone model provides detailed analysis of the boosted operation strategy, showing
that thermal efficiency increases significantly for lean-burn hydrogen mixtures. Operating
hydrogen engines at high loads presents challenges arising from combustion abnormalities
as increasing intake air pressure raises in-cylinder temperature, significantly increasing
knock occurrence and nitric oxide emissions. However, low-temperature combustion
through lean-burn and water injection has potential to mitigate combustion abnormalities
and reduce nitric oxide emissions; the addition of water modulates the rate at which
combustion occurs. A newly developed laminar flame speed correlation for hydrogen-air
combustion accounts for water addition under engine-relevant conditions. The applicability
of this new correlation is demonstrated by incorporating this empirical correlation into a
two-zone combustion model to predict engine performance, combustion abnormalities and
nitric oxide emissions. The simulation of a water-diluted hydrogen engine indicates that
emission control and knock mitigation are achievable, but requires careful optimization to
avoid significant reducing thermal efficiency. The simulations allow the production of a
hydrogen operational map based on the indicated specific fuel consumption, nitric oxide,
thermal efficiency, equivalence ratio, and water addition. A comprehensive exergy analysis
of a hydrogen engine evaluates efficiency, irreversibility, and emissions, quantifying losses
for each engine condition: intake manifold air pressure, fuel mixture, compression ratio,
water addition, and spark timing. This enables a discussion of the compromises for designing
and managing hydrogen-fuelled SI engines at various operating conditions, including
equivalence ratios, spark timings, compression ratio, and boosted manifold air pressure
Weight trajectories in aging humanized APOE mice with translational validity to human Alzheimer’s risk population: A retrospective analysis
Get PDFData Availability: All relevant data are within the manuscript and its Supporting Information files. Python code along with data are available at https://github.com/fransiss/AHMM_mouse_trajectories.Supporting information is available online at: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0314097#sec016 .Translational validity of mouse models of Alzheimer’s disease (AD) is variable. Because change in weight is a well-documented precursor of AD, we investigated whether diversity of human AD risk weight phenotypes was evident in a longitudinally characterized cohort of 1,196 female and male humanized APOE (hAPOE) mice, monitored up to 28 months of age which is equivalent to 81 human years. Autoregressive Hidden Markov Model (AHMM) incorporating age, sex, and APOE genotype was employed to identify emergent weight trajectories and phenotypes. In the hAPOE-AD mouse cohort, five distinct weight trajectories emerged: three trajectories were associated with a weight loss phenotype (36% of mice, n = 426), one with weight gain (13% of mice, n = 152), and one trajectory of no change in weight (34% of mice, n = 403). The AHMM model findings were validated with post-hoc survival analyses, revealing differences in survival rates across the five identified phenotypes. Further validation was performed using body composition and plasma β-amyloid data from mice within the identified gain, loss and stable weight trajectories. Weight gain trajectory was associated with elevated plasma β-amyloid levels, higher body fat composition, lower survival rates and a greater proportion of APOE4/4 carriers. In contrast, weight loss was associated with greater proportion of hAPOE3/ 4 carriers, better survival rates and was predominantly male. The association between weight change and AD risk observed in humans was mirrored in the hAPOE-AD mouse model. Weight trajectories of APOE3/3 mice were equally distributed across weight gain, loss and stability. Surprisingly, despite genetic uniformity, comparable housing, diet and handling, distinct weight trajectories and divergence points emerged for subpopulations. These data are consistent with the heterogeneity observed in the human population for change in body weight during aging and highlight the importance of longitudinal phenotypic characterization of mouse aging to advance the translational validity of preclinical AD mouse models.Research reported herein was supported by the National Institute on Aging (grants P01AG026572 [Perimenopause in Brain Aging and Alzheimer's Disease], T32AG061897 [Translational Research in Alzheimer's Disease and Related Dementias (TRADD)], 5R01AG057931-02 [Sex Differences in Molecular Dementias of Alzheimer's Disease Risk: Prodromal Endophenotype]), the Women's Alzheimer's Movement to Roberta Diaz Brinton, and the University of Arizona Center for Innovation in Brain Science
The 2024 Forum on Domestic Violence and the Hague Abduction Convention
No full textThis article discusses the recent Forum on Domestic Violence and the Operation of Article 13(1)(b) of the Hague Convention on the Civil Aspects of International Child Abduction sponsored by the Hague Conference on Private International Law. The article describes the reason for the Forum and highlights some of the important content that emerged at the event. It concludes with recommendations for the next Forum, scheduled to occur in Brazil during the second half of 2025.The authors are members of FiLiA Hague Mothers. They receive no financial reward for this work
For A Disappeared Cinema
Get PDFThe Soil and The Sea can be watched on Curzon Home Cinema
https://homecinema.curzon.com/film/the-soil-and-the-sea/ .For many the advent of cinema at the dawn of the 19th century brought an end to humanity’s long quest for an artistic medium that could present to audiences the physical world, in all its movements, colours and sounds. The photographic - thus mechanical - basis of cinema granted the new medium a purchase on everyday
reality that the visual arts could not achieve. This attitude has in many ways come to define cinema: this is born inside the material, physical world and thus its practice is constrained and of course made possible primarily by this very fact.British Academy, Funder reference: HDV190098 (Memories from the Margins. Bottom-up practices for dealing with conflict-produced heritage in Lebanon and Syria as new democratic spaces)
Problematising Sharenting of Supermoms in a Neoliberal Context
Get PDFThe representation of motherhood using digital platforms, which we call sharenting, can shape the socially constructed motherhood identity, i.e., supermoms in modern societies. Despite building a positive identity as mothers, supermoms may unintentionally violate their children’s privacy, instrumentalise, and even monetise the children. We examine sharenting and supermom identities as manifestations of neoliberal repositioning women as mothers and employees with little consideration of their unarticulated struggles. Drawing on a netnographic study of social media practices, we analysed fifteen working supermom accounts with over two hundred thousand followers, where child-related content was shared and posted between 2019 and 2023. We find that sharenting is often employed to construct the identity of supermoms, yet it frequently leads to the exploitation of children for profit-driven purposes, thereby increasing their vulnerability. We contribute to the literature by offering empirical evidence that the supermom identity is a by-product of the neoliberal system, which normalises time-intensive demands on women in the workplace and caregiving roles. Furthermore, we highlight the adverse consequences of sharenting and provide critical insights into the privacy and security risks associated with child-related digital content
Trajectory-Based Anycast Routing Protocol with MDRUs Assistance in Disaster Response Network
Get PDFModern rescue operations rely on wireless communications for safety reporting, area monitoring, and rescue coordination. However, natural disasters severely damage ground infrastructure, creating significant challenges for emergency rescue and recovery efforts. This paper establishes a disaster response network using Movable and Deployable Resource Units (MDRUs) in disaster-affected areas, to provide timely and reliable message transmission services. Firstly, to ensure a timely and efficient disaster response, we design a post-disaster emergency vehicle network architecture. Secondly, we propose a three-phase emergency relief model to dynamically deploy MDRUs, aiming to maximize their service coverage. Finally, we propose a Trajectory-Based Anycast Routing (TBAR) protocol, which enhances message transmission efficiency by optimizing route selection. Specifically, by facilitating the flexibility of any cast in delivering messages to anyone of the reachable MDRUs, TBAR utilizes multiple copies of messages to reduce end-to-end latency and increase the delivery ratio. Moreover, TBAR adaptively evaluates the message delivery capability of candidate vehicles using a multi-attribute decision-making algorithm, considering link quality, trajectory similarity, and distance cost. Extensive simulation results show that TBAR significantly outperforms other baseline algorithms in multiple aspects.10.13039/501100012166-National Key Research and Development Program of China (Grant Number: 2024YFB3108400). The research is supported in part by National Key Research and Development Program of China (2024YFB3108400), and Hubei Province Major Science and Technology Innovation Program (2024BAA011)
A Keypoint‐Guided Feature Partition Network for Occluded Person Re‐Identification
Get PDFData Availability Statement:
[Occluded-DukeMTMC]
The Occluded-DukeMTMC dataset used in this study is derived from the DukeMTMC-reID dataset. The resources are available at https://github.com/lightas/Occluded-DukeMTMC-Dataset. Researchers wishing to use this dataset must first obtain the DukeMTMC-reID dataset independently and then apply the conversion script [31].
[Market1501]
The Market-1501 dataset that supports the findings of this study is openly available in the public domain. The dataset contains training, query, and gallery partitions for person re-identification research and can be downloaded from the original release site at https://www.kaggle.com/datasets/sachinsarkar/market1501, or from other repositories hosting the dataset. These data are freely accessible under the original licencing terms [32].
[DukeMTMC-reID]
The DukeMTMC-reID dataset used in this study is a subset of the original DukeMTMC multi-camera tracking dataset. The dataset is available at https://www.kaggle.com/datasets/igorkrashenyi/dukemtmc-reid. Researchers should ensure compliance with licencing and ethical use requirements when downloading and using this dataset [33].Existing occluded person re‐identification methods employ hard or soft partition strategies to explore fine‐grained information. However, the hard partition strategy which extracts region‐level features may impair the semantic connectivity of correlated human body parts. A pose‐guided soft partition establishes correlations among human keypoints, while the generated pixel‐level embeddings may lose the surrounding semantic information. In this paper, we propose a keypoint‐guided feature partition (KGFP) method that consists of a feature extractor, a hard partition branch, and a soft partition branch. Specifically, we adopt a vision transformer and a pose estimator to extract features and keypoint information. In the hard partition branch, we partition features into distinct groups and classify them into nonoccluded, semi‐occluded, and occluded features to obtain region‐level features and filter out occlusions. Furthermore, we design a dissimilarity loss to reduce the similarity between semi‐occluded and occluded features. In the soft partition branch, we introduce a graph attention network and consider global and keypoint embeddings as nodes of a graph to discover interrelationships. Additionally, we formulate image alignment as a graph matching problem and propose a feature alignment‐based graph to reduce position misalignment. Extensive experiments demonstrate that the proposed method achieves superior performance compared to state‐of‐the‐art methods on Occluded‐DukeMTMC, Markt1501, and DukeMTMC‐reID.This work is supported in part by the National Natural Science Foundation of China (No. 62276038), and in part by the Scientific and Technological Research Program of Chongqing Municipal Education Commission (Grant KJZD-M202400603), and in part by the Project of Key Laboratory of Tourism Multisource Data Perception and Decision, Ministry of Culture and Tourism (No. H2023009)
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