cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Permeability of fracture networks generated through geomechanical fracture-growth simulations
Creators: name: Thomas, Robin Nicholas
Publisher: name: Imperial College London
Year: 2019

description: Fracture networks in subsurface rocks significantly impact the mechanical and hydraulic properties of the Earth. Realistic models of fracture networks underpin a variety of important geoscience fields. The physics of how fractures propagate and interact control how networks develop, but such processes are not routinely incorporated into discrete fracture network (DFN) models. This thesis presents a novel approach to model deformation of isotropic, homogeneous, and linear elastic brittle rocks, leading to the development of dense three-dimensional fracture networks. These networks provide realistic representations of subsurface networks that honour the physical process of concurrent fracture growth and interaction. This thesis proposes a number of novel developments that advance the field of discrete fracture modelling, with the aim of growing dense networks in a realistic manner. It presents a number of new validations for fracture growth and interaction, providing benchmarks for the accuracy required to generate realistic networks. Towards the goal of generating realistic fracture networks, several topics are studied numerically. A method for examining fracture interaction in three-dimensions is introduced, which quantifies the change in stress a fracture undergoes due to a neighborhood of nearby fractures. Fracture interaction is examined spatially in novel fracture interaction maps. Realistic fracture growth is demonstrated in both tension and compression. The effect of fracture interaction on mutual fracture growth is demonstrated on fracture arrays. The hydraulic properties of a spent UO\textsubscript{2} fuel pellet are quantified using an effective permeability computation method. The thesis concludes by presenting six geomechanical discrete fracture networks (GDFNs). The primary influences on the geometric and hydraulic properties of these GDFNs are the stresses causing growth and fracture interaction, rather than the random process of initial fracture insertion. GDFNs provide a new way of understanding subsurface processes, and improve our capacity to model hydro-mechanical processes in fractured rock masses.
HPC Midlands and Airbus Case Study - Predicting the Impact of Drilling in Carbon Epoxy Composites
Creators: name: Hamilton, Martin
Publisher: name: figshare
Year: 2013
Subjects: subject: Aerospace Engineering
subject: FOS: Mechanical engineering

description: Composite materials offer excellent strength-to-weight ratio,damage tolerance, and fatigue and corrosion resistance which make them good candidates for replacement of conventional materials for structural applications. As a result, advanced composite materials make up about 50% of the structural weight of a Boeing 787 and an Airbus A350XWB. They are also used in many other applications such as wind turbines and Formula One cars. The predictive modelling capabilities developed will be used by manufacturing experts, machining technicians and component assembly teams. Prior knowledge of the consequence of machining on these heterogeneous materials will help alleviate in-service failure and improve component life predictions, which will have far reaching economic benefits to industry as well as environmental and safety related benefits for the public. The work has been published in leading academic journals for wider dissemination to the academic community. For more information, please see http://hpc-midlands.ac.uk.
title: Fauna assemblages of the spinifex sand plains in central Australia
title: response to climate, fire and predation
titleType: Subtitle
Creators: name: Molyneux, Jennifer
Publisher: name: Charles Darwin University
Year: 2017

description: Australia’s arid zone is one of the most unique desert regions in the world due to its dominance across the continent, distinctive rainfall patterns, low soil nutrients and unique faunal assemblage. Drivers of faunal assemblages are varied, with rainfall, fire and predators considered most influential. The aim of this study was to identify the drivers of fauna persistence following a period of high rainfall and to refine management strategies in the spinifex sand plains of central Australia, with particular reference to the brush-tailed mulgara, Dasycercus blythi. I utilised broad scale fauna monitoring to assess the effect of environmental factors on persistence generally and conducted a detailed assessment of the fine-scale habitat use by D. blythi. I further compared the efficacy of three popular monitoring techniques utilised in the region. This study revealed large mammalian predators were most influential in predicting the occurrence of small mammals and reptile assemblages, whilst rainfall and temperature were most influential for invertebrates. The distribution of D. blythi populations contracted spatially during periods of low rainfall to areas of potential refuge. Fine scale habitat use indicating access to food resources was more influential than selecting areas with low exposure to predators. Infrared cameras sampled the broadest range of species and were the most cost effective over time, whilst sign surveys were most cost effective short term and live trapping essential in detecting several specific species. Overall, these findings inform land managers on the importance of gaining a better understanding of the invertebrate fauna in the region and implementing effective predator control during periods of low rainfall. By targeting management to specific areas of refuge land managers could reduce financial costs whilst maintaining support for key species, such as D. blythi. Land managers would further benefit from implementing a greater variety of monitoring techniques to maximise the effectiveness of monitoring both financially and statistically.
D1.1 Forward looking use cases, their requirements and KPIS/KVIS
Creators: name: Brochhaus, Maximilan
Publisher: name: Zenodo
Year: 2023
Subjects: Manufacturing
Energy
Automotive
Construction
KVI

description: This deliverable contains a uniform description of the use cases that are to be implemented and applied within the scope of TARGET-X. The benefits that are to be achieved through application of the use cases are collected and utilized determine the value proposition of the use cases. Furthermore, the deliverable contains the draft of a Methodological Assessment Framework (MAF) which employs Key Performance Indicators (KPI) and Key Value Indicators (KPI) to quantify the value proposition of the use cases from a technical, an economic and a societal perspective.
HPC Midlands and TATA Steel Case Study - Computer Modelling Radically Improves Welding Techniques
Creators: name: Hamilton, Martin
Publisher: name: figshare
Year: 2013
Subjects: subject: Mechanical Engineering
subject: FOS: Mechanical engineering

description: Welding is the most economical and effective way of joining metals permanently. It is a vital process for manufacturing economies and it is estimated that more than 50% of global domestic and engineering products contain welded joints. According to Dr Shuwen Wen, Principal Scientist from TATA Steel: “The results achieved so far show great promise in terms of the discovery of new materials and process routes to manufacture weld components with improved in-service performance which will lead to a significant reduction of cost and energy consumption. The availability of HPC Midlands has increased the computing power drastically and this could potentially speed up the delivery of the modelling solutions for advanced welding that are in urgent need by modern industry.” For more information, please see http://hpc-midlands.ac.uk.
HPC Midlands and RWE npower Case Study - Coatings for Industrial Gas Turbine Blades
Creators: name: Hamilton, Martin
Publisher: name: figshare
Year: 2013
Subjects: subject: Mechanical Engineering
subject: FOS: Mechanical engineering

description: Composite materials offer excellent strength-to-weight ratio,damage tolerance, and fatigue and corrosion resistance which make them good candidates for replacement of conventional materials for structural applications. As a result, advanced composite materials make up about 50% of the structural weight of a Boeing 787 and an Airbus A350XWB. They are also used in many other applications such as wind turbines and Formula One cars. The predictive modelling capabilities developed will be used by manufacturing experts, machining technicians and component assembly teams. Prior knowledge of the consequence of machining on these heterogeneous materials will help alleviate in-service failure and improve component life predictions, which will have far reaching economic benefits to industry as well as environmental and safety related benefits for the public. The work has been published in leading academic journals for wider dissemination to the academic community. For more information, please see http://hpc-midlands.ac.uk.
First-principles studies of Schottky barriers and tunneling properties at Al(111)/Si(111) and CoSi$_2$(111)/Si(111) interfaces
Creators: name: Nangoi, J. K.
name: Palmstrøm, C. J.
name: Van de Walle, C. G.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present first-principles calculations of Schottky barrier heights (SBHs) at interfaces relevant for silicon-based merged-element transmon qubit devices. Focusing on Al(111)/Si(111) and CoSi$_2$(111)/Si(111), we consider various possible interfacial structures, for which we study the relaxations of the atoms near the interface, calculate the formation energies and Schottky barrier heights, and provide estimates of the Josephson critical currents based on the WKB tunneling formalism as implemented in the Simmons/Tsu-Esaki model. We find that the formation energies and SBHs are very similar for all Al(111)/Si(111) structures, yet vary significantly for the CoSi$_2$(111)/Si(111) structures. We attribute this to the more covalent character of bonding at CoSi$_2$/Si, which leads to configurations with distinct atomic and electronic structure. Our estimated Josephson critical currents, which govern the behavior of merged-element transmons, provide insight into the trends as a function of Schottky-barrier height. We show that desirable qubit frequencies of 4-5 GHz can be obtained with a Si barrier thickness of about 5-10 nm, and demonstrate that the critical current density as a function of Schottky barrier height can be modeled based on the tunneling probability for a rectangular barrier.
description: Submitted to Physical Review B
Baby skyrmion crystals stabilized by vector mesons
Creators: name: Leask, Paul
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this letter we study soliton crystals in the $(2+1)$-dimensional analogue model of the $(3+1)$-dimensional Adkins--Nappi model of nuclear physics. The baby $ω$-Skyrme model studied here is an $O(3)$ nonlinear $σ$ model coupled to a massive vector meson, the $ω$-meson. Using recently developed methods in the $(3+1)$-dimensional $ω$-Skyrme model we are able to construct soliton crystals in this $(2+1)$-dimensional baby $ω$-Skyrme model. The resulting crystals form a hexagonal lattice structure and are qualitatively and quantitatively similar to crystals observed in the standard baby Skyrme model.
description: 4 pages, 1 figure
Theory of quasiparticle-induced errors in driven-dissipative Schrödinger cat qubits
Creators: name: Dubovitskii, Kirill
name: Basko, Denis M.
name: Meyer, Julia S.
name: Houzet, Manuel
Publisher: name: arXiv
Year: 2024
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Understanding the mechanisms of qubit decoherence is a crucial prerequisite for improving the qubit performance. In this work we discuss the effects of residual Bogolyubov quasiparticles in Schrödinger cat qubits, either of the dissipative or Kerr type. The major difference from previous studies of quasiparticles in superconducting qubits is that the Schrödinger cat qubits are operated under non-equilibrium conditions. Indeed, an external microwave drive is needed to stabilize "cat states", which are superpositions of coherent degenerate eigenstates of an effective stationary Lindbladian in the rotating frame. We present a microscopic derivation of the master equation for cat qubits and express the effect of the quasiparticles as dissipators acting on the density matrix of the cat qubit. This enables us to determine the conditions under which the quasiparticles give a substantial contribution to the qubit errors.
A link between the size and composition of comets
Creators: name: Robinson, James E.
name: Malamud, Uri
name: Opitom, Cyrielle
name: Perets, Hagai
name: Blum, Jürgen
Publisher: name: arXiv
Year: 2024
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: All cometary nuclei that formed in the early Solar System incorporated radionuclides and therefore were subject to internal radiogenic heating. Previous work predicts that if comets have a pebble-pile structure internal temperature build-up is enhanced due to very low thermal conductivity, leading to internal differentiation. An internal thermal gradient causes widespread sublimation and migration of either ice condensates, or gases released from amorphous ice hosts during their crystallisation. Overall, the models predict that the degree of differentiation and re-distribution of volatile species to a shallower near-surface layer depends primarily on nucleus size. Hence, we hypothesise that cometary activity should reveal a correlation between the abundance of volatile species and the size of the nucleus. To explore this hypothesis we have conducted a thorough literature search for measurements of the composition and size of cometary nuclei, compiling these into a unified database. We report a statistically significant correlation between the measured abundance of CO/H$_{2}$O and the size of cometary nuclei. We further recover the measured slope of abundance as a function of size, using a theoretical model based on our previous thermophysical models, invoking re-entrapment of outward migrating high volatility gases in the near-surface pristine amorphous ice layers. This model replicates the observed trend and supports the theory of internal differentiation of cometary nuclei by early radiogenic heating. We make our database available for future studies, and we advocate for collection of more measurements to allow more precise and statistically significant analyses to be conducted in the future.
description: 25 pages, 10 figures, published in MNRAS. Minor copyedit changes and updated links to data repositories
Navigating the EU AI Act: A Methodological Approach to Compliance for Safety-critical Products
Creators: name: Kelly, J.
name: Zafar, S.
name: Heidemann, L.
name: Zacchi, J.
name: Espinoza, D.
name: Mata, N.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: In December 2023, the European Parliament provisionally agreed on the EU AI Act. This unprecedented regulatory framework for AI systems lays out guidelines to ensure the safety, legality, and trustworthiness of AI products. This paper presents a methodology for interpreting the EU AI Act requirements for high-risk AI systems by leveraging product quality models. We first propose an extended product quality model for AI systems, incorporating attributes relevant to the Act not covered by current quality models. We map the Act requirements to relevant quality attributes with the goal of refining them into measurable characteristics. We then propose a contract-based approach to derive technical requirements at the stakeholder level. This facilitates the development and assessment of AI systems that not only adhere to established quality standards, but also comply with the regulatory requirements outlined in the Act for high-risk (including safety-critical) AI systems. We demonstrate the applicability of this methodology on an exemplary automotive supply chain use case, where several stakeholders interact to achieve EU AI Act compliance.
description: To be published in: 2024 IEEE Conference on Artificial Intelligence (CAI 2024)
High-level synthesis of fine-grained weakly consistent C concurrency
Creators: name: Ramanathan, Nadesh
Publisher: name: Imperial College London
Year: 2019

description: High-level synthesis (HLS) is the process of automatically compiling high-level programs into a netlist (collection of gates). Given an input program, HLS tools exploit its inherent parallelism and pipelining opportunities to generate efficient customised hardware. C-based programs are the most popular input for HLS tools, but these tools historically only synthesise sequential C programs. As the appeal for software concurrency rises, HLS tools are beginning to synthesise concurrent C programs, such as C/C++ pthreads and OpenCL. Although supporting software concurrency leads to better hardware parallelism, shared memory synchronisation is typically serialised to ensure correct memory behaviour, via locks. Locks are safety resources that ensure exclusive access of shared memory, eliminating data races and providing synchronisation guarantees for programmers. As an alternative to lock-based synchronisation, the C memory model also defines the possibility of lock-free synchronisation via fine-grained atomic operations (`atomics'). However, most HLS tools either do not support atomics at all or implement atomics using locks. Instead, we treat the synthesis of atomics as a scheduling problem. We show that we can augment the intra-thread memory constraints during memory scheduling of concurrent programs to support atomics. On average, hardware generated by our method is 7.5x faster than the state-of-the-art, for our set of experiments. Our method of synthesising atomics enables several unique possibilities. Chiefly, we are capable of supporting weakly consistent (`weak') atomics, which necessitate fewer ordering constraints compared to sequentially consistent (SC) atomics. However, implementing weak atomics is complex and error-prone and hence we formally verify our methods via automated model checking to ensure our generated hardware is correct. Furthermore, since the C memory model defines memory behaviour globally, we can globally analyse the entire program to generate its memory constraints. Additionally, we can also support loop pipelining by extending our methods to generate inter-iteration memory constraints. On average, weak atomics, global analysis and loop pipelining improve performance by 1.6x, 3.4x and 1.4x respectively, for our set of experiments. Finally, we present a case study of a real-world example via an HLS-based Google PageRank algorithm, whose performance improves by 4.4x via lock-free streaming and work-stealing.
Prospects of nuclear-coupled-dark-matter detection via correlation spectroscopy of I$_2^+$ and Ca$^+$
Creators: name: Madge, Eric
name: Perez, Gilad
name: Meir, Ziv
Publisher: name: arXiv
Year: 2024
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The nature of dark matter (DM) and its interaction with the Standard Model (SM) is one of the biggest open questions in physics nowadays. The vast majority of theoretically-motivated Ultralight-DM (ULDM) models predict that ULDM couples dominantly to the SM strong/nuclear sector. This coupling leads to oscillations of nuclear parameters that are detectable by comparing clocks with different sensitivities to these nature's constants. Vibrational transitions of molecular clocks are more sensitive to a change in the nuclear parameters than the electronic transitions of atomic clocks. Here, we propose the iodine molecular ion, I$_2^+$, as a sensitive detector for such a class of ULDM models. The iodine's dense spectrum allows us to match its transition frequency to that of an optical atomic clock (Ca$^+$) and perform correlation spectroscopy between the two clock species. With this technique, we project a few-orders-of-magnitude improvement over the most sensitive clock comparisons performed to date. We also briefly consider the robustness of the corresponding "Earth-bound" under modifications of the $Z_N$-QCD axion model.
description: 10 pages, 4 figures; v2 matches version published in PRD
Using the Coefficient of Variation to Improve the Sparsity of Seismic Data
Creators: name: Al-Marzouqi, Hasan
name: AlRegib, Ghassan
Publisher: name: figshare
Year: 2013
Subjects: Applied Computer Science

description: In this work we propose using the coefficient of variation as a cost function to improve seismic data representation in the curvelet domain. Performance improvement is demonstrated in denoising and compressed sensing data recovery. The demonstrated approach can be extended to other seismic applications and alternate transforms.
title: The Good, the Bad and the Ugly: The Commission Proposes Freezing Funds to Hungary
Creators: name: Scheppele, Kim Lane
name: Kelemen, R.
name: Morijn, John
Publisher: name: Fachinformationsdienst für internationale und interdisziplinäre Rechtsforschung
Year: 2022
Subjects: subject: 342

description: Verfassungsblog: On Matters Constitutional
HPC Midlands and E.ON Case Study - Predicting the Impact of Air Flow on Off-shore Energy Generation
Creators: name: Hamilton, Martin
Publisher: name: figshare
Year: 2013
Subjects: subject: Mechanical Engineering
subject: FOS: Mechanical engineering

description: Off-shore wind farms are recognised as having enormous potential to reduce reliance on fossil fuels and contribute significantly to UK renewable energy generation targets. However, they demand huge levels of investment and, if that is to be justified, there needs to be greater certainty about financial and environmental returns. Loughborough University has considerable expertise in wind energy generation and computational fluid dynamics (CFD) modelling, the branch of physics used for detailed prediction of air flows. This specialist expertise, combined with access to the high performance computing (HPC) infrastructure and know-how, made the University the ideal partner for E.ON.
Review of nanofluid through solar collector for Domestic Applications
Creators: name: Maryam A.H.
name: Adnan M.H.
Publisher: name: gjrpublication
Year: 2024

description: Energy management and the usage of renewable energy sources are essential for a sustainable future. This paper carried out a review and summarize recent topic of solar collectors heating water for use in a domestic application. Several researchers have studied solar collectors with flat plates, evacuated, and concentrators to improve heat gain for heating water. Entropy is an important function that the attention of investigators to reduce and increase the thermal efficiency of solar collectors. Nanofluid has been selected as have found a new class of thermal efficiency enhancement and has been selected for this purpose. Thermal performance is enhanced by changing the geometry of the absorber plate of the solar collector and the evacuated tube is the best. It was found that increasing nanoparticle concentration to 4% improves solar collector efficiency to 30%. It was observed that the report of solar-collector enhancement by changing geometry and fluid flow through the solar-collector.
Design of reconfigurable Huygens metasurfaces based on Drude-like scatterers operating in the epsilon-negative regime
Creators: name: Monti, Alessio
name: Vellucci, Stefano
name: Barbuto, Mirko
name: Stefanini, Luca
name: Ramaccia, Davide
name: Toscano, Alessandro
name: Bilotti, Filiberto
Publisher: name: arXiv
Year: 2024
Subjects: subject: Applied Physics (physics.app-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In this study, we investigate the feasibility of designing reconfigurable transmitting metasurfaces through the use of Drude-like scatterers with purely electric response. Theoretical and numerical analyses are provided to demonstrate that the response of spherical Drude-like scatterers can be tailored to achieve complete transmission, satisfying a generalized Kerker's condition at half of their plasma frequency. This phenomenon, which arises from the co-excitation of the electric dipole and the electric quadrupole within the scatterer, also exhibits moderate broadband performance. Subsequently, we present the application of these particles as meta-atoms in the design of reconfigurable multipolar Huygens metasurfaces, outlining the technical prerequisites for achieving effective beam-steering capabilities. Finally, we explore a plausible implementation of these low-loss Drude-like scatterers at microwave frequencies using plasma discharges. Our findings propose an alternative avenue for Huygens metasurface designs, distinct from established approaches relying on dipolar meta-atoms or on core-shell geometries. Unlike these conventional methods, our approach fosters seamless integration of reconfigurability strategies in beam-steering devices.
Integer and fractional quantum anomalous Hall effects in pentalayer graphene
Creators: name: Xie, Ming
name: Sarma, Sankar Das
Publisher: name: arXiv
Year: 2024
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We critically analyze the recently reported observation of integer (IQAHE) and fractional (FQAHE) quantum anomalous Hall effects at zero applied magnetic field in pentalayer graphene. Our quantitative activation and variable range hopping transport analysis of the experimental data reveals that the observed IQAHE and FQAHE at different fillings all have similar excitation gaps of the order of $5-10$ K. In addition, we also find that the observed FQAHE manifests a large hidden background contact series resistance >10 k$Ω$ of unknown origin whereas this contact resistance is much smaller ~500 $Ω$ in the observed IQAHE. Both of these findings are surprising as well as inconsistent with the well-established phenomenology of the corresponding high-field integer and fractional quantum Hall effects in 2D semiconductor systems.
description: Final published version
Survivorship, Site Fidelity and Weight Dynamics of Male Hybomitra aurilimba (Diptera: Tabanidae) at a Hilltop Mating Arena
Creators: name: Smith, Stephen M
Publisher: name: figshare
Year: 2013
Subjects: subject: Ecology
subject: FOS: Biological sciences

description: I present a mark-release-recapture study of individually marked males of the horsefly Hybomitra aurilimba (Stone) (Diptera: Tabanidae) at a hilltop mating arena in southern Ontario, Canada; the study occupied much of the seasonal on-wing period of the males. Survivorship, population size, daily recruitment and site fidelity were examined by recapture of marked males. Flies were often recaptured on the day of marking and thereafter on up to 7 different days, covering periods up to 16 d following marking. The population was small (<100 males) with a relatively high daily recruitment. The males exhibited pronounced and prolonged fidelity to both the overall mating arena and to individual hovering sites within the arena. Mean daily survivorship was relatively high (0.84 ± 0.021 (SEM)), leading to a mean on-site residency time of 5.7 d (95% CL: 4.4–7.9 d). Marked and recaptured males were weighed; they exhibited highly individual patterns of substantial weight losses and gains, both within and among days.
An Insight of Heart-Like Systems with Percolation
Creators: name: Molla, Md Aquib
name: Goswami, Sanchari
Publisher: name: arXiv
Year: 2024
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study the signal percolation through heart-like biological system. Starting from an initial distribution of waiting and inactive cells with probabilities $p$ and $(1-p)$ respectively, the signal propagation is observed in terms of active cells. As the signal enters the system from one end, the number of arrival of active sites at the other end is studied and analysis of the system behaviour is made by varying a few important parameters of the system like $p_{switch}$ (switching probability from inactive to waiting) and $p_{act}$ (switching probability from waiting to active). In this connection, the non-regular heart rhythms are discussed. Fraction of paths percolating through the system shows a transition from $0$ to $1$ near $p=p_c$. Some other important quantities like tortuosity and cluster distribution are discussed. Several critical exponents have been obtained and compared the exponents of standard percolation.
description: 11 pages, 10 figures, 4 tables, revtex4-2
RATIONAL USE OF WATER RESOURCES, EFFECTIVENESS OF IRRIGATION TECHNOLOGIES ADAPTED TO CLIMATE CHANGE CONDITIONS
Creators: name: Tolibova, Muhabbat
name: Asadov, Bekjon
name: Nasibov, Boburbek
Publisher: name: Zenodo
Year: 2024

description: This article explores the critical need for innovative irrigation technologies in the face of climate change impacts on agriculture and water resources. With changing precipitation patterns and increasing water scarcity, the rational use of water resources becomes imperative. The review focuses on the effectiveness of various irrigation technologies, particularly precision irrigation, in adapting to evolving climatic conditions. Findings reveal that precision irrigation methods, including drip and micro-sprinkler systems, offer significant benefits by conserving water and enhancing system resilience. These technologies deliver water directly to plant roots, reducing evaporation and runoff. Additionally, integrating soil moisture sensors and weather data optimizes irrigation scheduling, further enhancing efficiency. Moreover, the article underscores the importance of sustainable water management practices to combat water scarcity, such as drip irrigation, rainwater harvesting, and smart irrigation systems. These approaches not only conserve water but also reduce energy consumption and greenhouse gas emissions associated with agriculture.
title: Feministische Zeitpolitik: Folge 30
Creators: name: Gather, Selma
name: Valentiner, Dana-Sophia
Publisher: name: Fachinformationsdienst für internationale und interdisziplinäre Rechtsforschung
Year: 2022
Subjects: subject: 340

description: Warum ist Zeit ein feministisches Thema? Und wie könnte unsere Gesellschaft (geschlechter)gerechter werden, wenn wir alle mehr Zeit jenseits der Lohnarbeit hätten? Über diese Fragen sprechen die Moderatorinnen und Juristinnen Selma Gather und Prof. Dr. Dana-Sophia Valentiner mit der Journalistin und Autorin Teresa Bücker. Die Juristin Alice Bertram, die eine juristische Promotion zum Thema Zeit im Recht verfasst hat, erläutert, wie Recht und Zeit zusammenhängen. Teresa Bücker erklärt im Interview, warum sie meint, dass Zeit ins Zentrum politischer Forderungen gehört. Sie spricht über die Leerstelle(n) im Equal Care-Diskurs, über die Notwendigkeit einer feministischen Kritik an der Vollzeitnorm, über den Zusammenhang von Zeit und politischer Teilhabe und um wieviel wir alle unsere Arbeitswochenstunden reduzieren müssten, um zu einer inklusiveren, gerechteren und freieren Zeitkultur zu kommen. In jedem Fall eine gut investierte Stunde!
Candidate quantum spin liquids on the maple-leaf lattice
Creators: name: Sonnenschein, Jonas
name: Maity, Atanu
name: Liu, Chunxiao
name: Thomale, Ronny
name: Ferrari, Francesco
name: Iqbal, Yasir
Publisher: name: arXiv
Year: 2024
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Motivated by recent numerical studies reporting putative quantum paramagnetic behavior in spin-$1/2$ Heisenberg models on the maple-leaf lattice, we classify Abrikosov fermion mean-field Ansätze of fully symmetric $U(1)$ and $\mathbb{Z}_{2}$ quantum spin liquids within the framework of projective symmetry groups. We obtain a total of $17$ $U(1)$ and $12$ $\mathbb{Z}_{2}$ algebraic PSGs, and, upon restricting their realization via mean-field Ansätze with nearest-neighbor amplitudes (relevant to the studied models), only 12 $U(1)$ and 8 $\mathbb{Z}_{2}$ distinct phases are obtained. We present both singlet and triplet fields for all Ansätze up to third nearest-neighbor bonds and discuss their spinon dispersions as well as their dynamical spin structure factors. We further assess the effects of Gutzwiller projection on the equal-time spin structure factors, and identify a $U(1)$ Fermi surface spin liquid whose structure factor most closely reproduces the one obtained from pseudo-fermion functional renormalization group calculations.
description: 28 pages, 21 figures, 7 tables
A Case Study for NoSQL Applications and Performance Benefits: CouchDB vs. Postgres
Creators: name: Hanlon, Matthew
Publisher: name: figshare
Year: 2015
Subjects: Applied Computer Science

description: As HPC continues driving towards exascale, there is an in- creasing need to access and interface with massive data sets. As such interactions become more commonplace, developers need to readdress how data is stored and rethink the in- frastructure to enable efficient access and analysis of data. It is becoming evident that traditional, relational databases are not always the most appropriate solution to allow users on-demand access to big data sets. In this study we show that using non-relational, ”NoSQL” databases, such as doc- ument stores or key-value stores, can offer large benefits in performance, accessibility and availability. We present a use case from the TeraGrid User Portal that demonstrates a NoSQL solution for auditing and processing batch job data efficiently in order to provide users rapid access to this data. We also present an analysis of benchmarking data to iden- tify usage patterns and data sets for which each architecture is best suited.
Rowan T., 202x, Data & Code, Observations of tidal induced responses in Self-Potential data in a UK beach sand aquifer: Implications for monitoring seawater intrusion
Creators: name: Rowan, Thomas
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 370703
subject: Groundwater hydrology

description:

Affordable and effective early warning of saline intrusion into aquifers is a key challenge affecting coastal water supplies. This paper reports on the application of Self Potential (SP) monitoring close to a mobile saline-fresh water interface over a 3-month period. SP was monitored in 12 boreholes, distributed over a variety of depths and distances to the high-water mark (HWM). Logged borehole measurements of groundwater level, temperature and fluid electrical conductivity (FEC) were also collected. Power Spectral Density (PSD) analysis of SP data showed a clear semi-diurnal (principal-lunar, M2) tidal component, with an amplitude of around 1 mV. The magnitude of the M2 component linearly decreased with depth and distance from the shore. Whilst PSD analysis showed M2 components in borehole water levels, none were detected in groundwater temperature and FEC. The results suggest that SP M2 components were generated remote from the boreholes by the movement of a saline interface, most likely associated with the upper saline plume. Superimposed on these tidal signals were periodic rises and falls in mean SP of around 5 – 10 mV. These responses appear to be linked to storm surge events, during which seawater advanced up to and beyond the monitoring boreholes. Although detailed interpretation of the data is complex due to salinity changes at the site of the reference electrode, they provide further support for the use of SP as a precursor to saline intrusion.
title: #23 Klimavölkerrecht: COP 27
Creators: name: Tuchtfeld, Erik
name: Lischewski, Isabel
name: Eschenhagen, Philipp
name: Schuberth, Sophie
Publisher: name: Fachinformationsdienst für internationale und interdisziplinäre Rechtsforschung
Year: 2022
Subjects: subject: 341

description: Wir werfen einen ausführlichen Blick auf das Klimavölkerrecht anlässlich der Conference of the Parties in Sharm el Sheikh (COP 27). Im Interview mit Philipp Eschenhagen hören wir von Christina Voigt einen „Werkstattbericht“ live von der COP 27 und erfahren mehr über ihre Rolle als Co-Vorsitzende des Paris Agreement Implimentation and Compliance Committee. In inhaltlicher Hinsicht sprechen wir vor allem über die Verpflichtungen von Staaten, Schadensersatz bzw. Entschädigungszahlungen für historische Emissionen an vom Klimawandel besonders stark betroffene Staaten zu leisten. Isabel Lischewski ordnet im Grundlagenteil außerdem die Rechtsnatur der Klimarahmenkonvention an. Wir freuen uns über Lob, Anmerkungen und Kritik an podcast@voelkerrechtsblog.org. Abonniert unseren Podcast via RSS, über Spotify oder überall dort, wo es Podcasts gibt. Es gibt die Möglichkeit, auf diesen Plattformen den Völkerrechtspodcast zu bewerten, wir freuen uns sehr über 5 Sterne! Hintergrundinformationen: Naomi Klein, From Blah, Blah, Blah to Blood, Blood, Blood, The Intercept (7 October 2022) Tagesschau, COP 27 einigt sich auf Abschlusserklärung Moderation: Philipp Eschenhagen & Erik Tuchtfeld Grundlagen: Dr. Isabel Lischewski Interview: Prof. Dr. Christina Voigt & Philipp Eschenhagen Schnitt: Daniela Rau Credits: UN Secretary-General at the first official plenary session of the COP 27 (gekürzt) Greta Thunberg, „Blah Blah Blah“ Speech at Youth4Climate Italy 2021
description: Völkerrechtsblog
Design, calibration and use of quantitative alpha-induced radioluminescence detectors
Creators: name: Pearce, Benjamin Charles
Publisher: name: Imperial College London
Year: 2019

description: The detection of alpha-emitting radioactive materials using UV radioluminescence methods has been subject to increasing attention in recent years. By detecting the UV photons emitted when alpha particles interact with nitrogen and other molecules in air, this method provides the opportunity to detect alpha-emitting radionuclides at distances beyond the small path length of alpha particles in air. To date – while detectors have been shown to detect alpha-emitting materials at large distances, in low quantities and in short duration – the capability of such detectors to produce accurate, repeatable, quantitative measurements of alpha-emitting sources has not been comprehensively explored. This lack means that comparison of the technique with others employed by industry has not been possible and little work has considered how devices’ analytical performance might be assessed. This thesis presents methods for the calibration of alpha-induced radioluminescence detectors against traceable sources of known activity to enable the quantitative estimation of sources of unknown activity. The design of a novel, portable detector capable of such measurements over a range of distances is presented, along with findings about the ideal design of detectors for quantitative measurement. This detector was shown to perform effectively in a wide variety of operating environments, ranging from light tight boxes to operational lighting in one of Sellafield’s active laboratories. The detector was used to develop four calibration methods – manual calibration, microprocessor-controlled confinement of a source, conveyor-based scanning and imaging by varying the pan/tilt angle of the detector. Using these methods, it was shown that the detector’s response scales linearly with the activity of americium-241 sources measured. Through the analysis of performance of two methods, it was shown that calibrations should only be applied to measurements obtained using the same acquisition process. This method of performance analysis provides a framework the for comparison of both methodological and detector performance.
Distinguishing radiation mechanisms and particle populations in blazar jets through long-term multi-band monitoring with RINGO3 and Fermi
Creators: name: McCall, Callum
name: Jermak, Helen
name: Steele, Iain A.
name: Agudo, Iván
name: de Almeida, Ulisses Barres
name: Hovatta, Talvikki
name: Lamb, Gavin P.
name: Lindfors, Elina
name: Mundell, Carole
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present the results of seven years of multicolour photometric monitoring of a sample of 31 $γ$-ray bright blazars using the RINGO3 polarimeter on the Liverpool Telescope from 2013--2020. We explore the relationships between simultaneous observations of flux in three optical wavebands along with Fermi $γ$-ray data in order to explore the radiation mechanisms and particle populations in blazar jets. We find significant correlations between optical and $γ$-ray flux with no detectable time lag, suggesting leptonic emission processes in the jets of these sources. Furthermore, we find the spectral behaviour against optical and $γ$-ray flux for many sources is best fit logarithmically. This is suggestive of a transition between bluer-/redder-when-brighter into stable-when-brighter behaviour during high activity states; a behaviour that might be missed in poorly sampled data, resulting in apparent linear relationships.
description: 32 pages, 35 figures
Polyphenolic profile of Asphodelus fistulosus L. roots and evaluation of their antioxidant, anti-haemolytic activities and toxicity
Creators: name: Kitouni, Rachid
name: Kabouche, Zahia
name: Bouldjadj, Redouane
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: FOS: Biological sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer

description: The polyphenolic profile of the hydroethanol extract of Asphodelus fistulosis L. roots (HEAFR) was determined using LC-HRMS/MS technique while its antioxidant activity was evaluated using five different methods (DPPH, reducing power, reduction via Fe+2 phenanthroline complex formation, ABTS•+, silver ion reduction capacity). In addition, preliminary toxicity and cytotoxicity of the HEAFR were assessed on larvae. The results revealed the presence of 40 polyphenols, with luteolin (23.89%), luteolin-7-O-β-D-glucoside (15.32%), emodin (13.49%) and feruloyltyramine (10.57%) as major compounds. The highest antioxidant activity was shown in the ABTS•+ assay (IC50: 89.34 ± 5.65 μg/mL) whereas preliminary toxicity and cytotoxicity tests showed that this extract is non-toxic. Moreover, the HEAFR exhibited a good protective effect of erythrocyte membranes at a high concentration of 800 μg/mL and showed comparable stabilisation efficiency to gallic acid at a concentration of 200 μg/mL. These findings highlight the HEAFR potential as a non-toxic antioxidant agent with protective effects on cell membranes.
Adiabatic Approximation and Aharonov-Casher Bands in Twisted Homobilayer TMDs
Creators: name: Shi, Jingtian
name: Morales-Durán, Nicolás
name: Khalaf, Eslam
name: MacDonald, Allan H.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Topological flat moiré bands with nearly ideal quantum geometry have been identified in homobilayer transition metal dichalcogenide moiré superlattices, and are thought to be crucial for understanding the fractional Chern insulating states recently observed therein. Previous work proposed viewing the system using an adiabatic approximation that replaces the position-dependence of the layer spinor with a nonuniform periodic effective magnetic field. When the local zero-point kinetic energy of this magnetic field cancels identically against that of an effective Zeeman energy, a Bloch-band version of Aharonov-Casher zero-energy modes, which we refer to as Aharonov-Casher band, emerges leading to ideal quantum geometry. Here, we critically examine the validity of the adiabatic approximation and identify the parameter regimes under which Aharonov-Casher bands emerge. We show that the adiabatic approximation is accurate for a wide range of parameters including those realized in experiments. Furthermore, we show that while the cancellation leading to the emergence of Aharonov-Casher bands is generally not possible beyond the leading Fourier harmonic, the leading harmonic is the dominant term in the Fourier expansions of the zero-point kinetic energy and Zeeman energy. As a result, the leading harmonic expansion accurately captures the trend of the bandwidth and quantum geometry, though it may fail to quantitatively reproduce more detailed information about the bands such as the Berry curvature distribution.
Una relectura del método sociológico: Emile Durkheim y el estudio científico de las formaciones sociales
Creators: name: Cerón, Zully
Publisher: name: unknown
Year: 2024

description: Se explica la influencia del método científico en el estudio de las formaciones sociales, lo cual destaca cómo Durkheim establece la sociología como una disciplina independiente y objetiva, enfocada en los hechos sociales como "cosas" externas al individuo. Lorente subraya la importancia de este enfoque para separar la sociología de la filosofía y la psicología, y revisa cómo sus principios metodológicos han influido en distintas escuelas sociológicas y antropológicas.
Quantum dynamics of photoexcited electrons in plasmonic nanostructures
Creators: name: Crai, Alexandra
Publisher: name: Imperial College London
Year: 2019

description: The light-matter interaction in nanoscale electronic systems is a fundamental question with relevance in numerous modern applications of plasmonic nanostructures. This thesis approaches the topic from two different directions. In the first part, a quantum model is proposed to describe a plasmonic nanostructure as a fundamental platform to investigate the optical response of the electrons. In the second part, the complex properties of plasmonic nanocavities are exploited to control the quantum dynamics of a single emitter placed in its near-field environment. With recent experiments investigating progressively smaller nanoparticles, quantum effects come into play and a microscopic description of the electron structure is required. In the proposed model, a density matrix formalism is used to analyse the photoexcited few-electron dynamics in a small plasmonic nanosphere. Starting from the standard derivation of the bulk plasmon one aims particularly at elucidating the role of the Coulomb interaction. The ability to calculate the linear and non-linear response of the system under various excitation conditions is demonstrated. The linear response is characterised by discrete resonances modified by a Coulomb interaction mediated collective response. In the strong excitation regime, there are optically induced oscillations of the occupations which strongly deviate from Rabi oscillations in a two-level system due to the non-linearity of the Coulomb interaction. The fundamental limit of a single quantum emitter coupled to a plasmonic mode constitutes another example of light-matter interaction on the nanoscale. In this thesis, it is shown that an electron beam exciting a nanometre-size plasmonic nanocavity induces the strong coupling of a single emitter placed in the gap and the plasmon mode. It is further shown that the interaction of the swift electrons with the metal is changing non-intuitively with their velocity for different geometries due to the different coupling channels. This behaviour is then explored to actively control the quantum dynamics of the emitter.