bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-term filtration of particles in a porous medium
Authors: Kuzmina Liudmila , Osipov Yuri
Published: June 2024

The formation of grout sediment in the pores of loose rock increases the water resistance of the soil and strengthens the foundation. A one-dimensional model of filtration in a porous medium considers the particles transport by the flow of a carrier fluid and the deposition of particles on the framework of a porous medium. The purpose of the work is to study the concentrations of suspended and settled particles of a suspension over a long time. Exact and asymptotic methods are used to obtain a solution to the model. The exact solution is presented in an implicit integral form. A set of solutions in the form of traveling waves with an arbitrary initial condition and their asymptotics are constructed. For the exact solution, an explicit second-order asymptotic solution for a long time is obtained as an expansion in decreasing exponents. Comparison of the asymptotic solution with the traveling waves makes it possible to choose a single traveling wave corresponding to the exact solution. The closeness of the traveling wave to the exact solution of the filtration model is verified numerically. The traveling wave found determines the explicit asymptotics of the concentration of deposited particles for a long time.
Numerical and Asymptotic Solutions for Multi Particle Bridging in Filtration Process
Authors: Safina Galina Leonidovna
Published: June 2024

The preservation of cultural and historic buildings is an important task for society. Historical buildings are prone to the appearance of numerous cracks and damage, therefore they require strengthening of their foundations and soils. Strengthening the foundations of historic buildings using injection methods is a technique used to improve and restore the foundations of old or damaged buildings. This method involves injecting special injection materials into the soil or foundation structure to improve its bearing capacity, stability and durability. The study of suspension flow with suspended solids in a porous medium is an integral part of ensuring the effectiveness of injection techniques. The paper considers a classical filtration model with a nonlinear filtration function. As a concentration function, a fifth-degree polynomial is used, describing the dimensional mechanism of particle capture in combination with the formation of arched partitions consisting of three or five particles blocking the pores. The considered problem with nonlinear filtration function and concentration function does not have an analytical solution, the paper presents its numerical solution using finite difference schemes. In addition to the numerical solution, expressions of analytical asymptotic solutions are obtained, which approximate the numerical solutions quite well even at sufficiently large values of time.
Features of construction control in the construction of high-rise buildings
Authors: Lapidus Azarij , Yan Jingjing , Telpiz Irina
Published: June 2024

With the continuous development of the social economy and the relentless progress of modernization, the construction industry has greatly contributed to the rapid development of urban planning. High-rise buildings are playing an increasingly important role in Russia’s economic construction. Based on the research and analysis of the current state of high-rise building development in the world and Russia, as well as the technical characteristics of construction control, to summarize the current problems in the high-rise building construction control field in Russia and put forward the relevant control measures. Based on an extensive review of scientific literature at home and abroad, this study analyzed the following issues as high-rise building construction control in terms of development history, influencing factors, and technical characteristics of Russian high-rise buildings, where the key focus was on the historical development and technical attributes of high-rise buildings in Russia; the current shortcomings and development prospects of Russian high-rise buildings were identified, and analogies and graphical analogies were proposed. In Russia, the development of high-rise buildings is hampered by the fact that 30 years ago, there was no unified regulatory and research base on high-rise building management. Currently, the Russian Ministry of Construction is actively developing normative and methodological documents to make up for inactive and outdated records in the field of high-rise buildings.
Sustainable buildings design strategies in the building sector
Authors: Naji Alaa Jaleel , Mahadi Mohamed I. Abu , Humaish Wisam Hafidh , Markovich Alexey S.
Published: June 2024

The building sector faces critical challenges such as negative impacts on the environment, high energy consumption, and cost inflation. With the development of digital technologies, BIM is increasingly being used in cooperation with other techniques to achieve sustainable building goals. This research aims to evaluate the current status of the sustainable building design strategies associated with BIM technologies. The most frequently cited sustainable building design strategies were identified by a comprehensive relevant literature review. A survey is conducted, focusing on a group of professionals in the sustainable construction sector, to measure the effectiveness of selected strategies. The results indicated that the “BIM-Based Life Cycle Assessment Method” and “BIM-Based Sustainability Rating Systems Method” were the most effective strategies. BIM can reduce the effort of performing various kinds of sustainability assessments. Thus, improving the performance of sustainable buildings during the design, construction, operation, and maintenance stages.
Information support for the New Silk Road project
Authors: Nurzhanova Sharipa Syzdykovna , Mukanova Gyulnar Kairollinovna , Kopbayev Timurgali , Zykov Nikolay Appolonovich
Published: June 2024

The New Silk Road project is the largest infrastructure project of recent decades. Its successful implementation promises significant economic benefits to participating countries. For the successful implementation of the project, information support is required at all stages of the project. It must be thoughtful and coordinated.
Russian chemical complex in 2022: Technology and machinery
Authors: Savinkov Sergey V. , Kiselev Vladimir M. , Okunkova Elena A. , Akulinin Fedor V. , Kolesnikov Anatoly V. , Zhurov Yury V.
Published: June 2024

The article presents the results of the analysis of the technological support of the Russian chemical industry conducted by the authors following the results of 2022, including the characteristics of fixed assets of universal and specialized equipment in terms of changes in the book value of machinery and equipment, equipment wear. It is shown that the deterioration of the situation for the Russian chemical complex has not significantly affected the stability of established production facilities of domestic enterprises producing chemical goods important for the country's economy. The production of plastics, ammonia and methanol is equipped with the most modern equipment, stable production of calcined and caustic soda, tires and rubber products, as well as the production of mineral fertilizers have the greatest wear. A negative factor is the dependence of the chemical complex on the import of foreign high-tech equipment to a high degree of digitalization and automation, which applies to almost all productions of the Russian chemical complex, which did not prevent us from concluding that the positive trend.
Tax burden as a factor in the sustainability of IT companies: Post-COVID dynamics in Russia
Authors: Vylkova Elena , Pokrovskaia Natalia , Zhigalov Viacheslav , Muraveva Oksana , Veyner Irina
Published: June 2024

The dynamics of the tax burden as a factor in the economic sustainability of Russian IT companies from pre-COVID 2019 to post-COVID 2021, taking into account the scale of their activities is studied herein. In terms of new challenges for companies in the IT sector as a system-forming industry, one of the key areas is to increase sustainability, which contributes to sustainable development in the face of adverse external influences. The purpose of the study is to determine the regions of Russia with the lowest tax burden in the IT sector, as well as the size of IT companies with the lowest tax burden in the specified period. For this purpose, statistical methods are used, in particular, the calculation of average measures of trends in terms of the tax burden of IT companies by region, with consideration to the size of companies. This made it possible to identify best practices and favorable conditions for the development of IT business in terms of tax burden. In parallel, the study shows the importance of the territorial factor of economic sustainability, since IT companies in regions with a favorable tax regime have a low level of tax burden.
Approach to typologization of territories by the level of investment potential using methods of cluster analysis (on the example of the constituent entities of the Far Eastern macroregion)
Authors: Nizamutdinov Marsel , Penchuk Anastasia , Akhmetzyanova Milyausha
Published: June 2024

The article deals with the problem of improving the sustainability of social and economic development of the Far Eastern Federal District (FEFD). The possibilities and limitations of the most well-known approaches and methodologies for assessing the investment climate are considered. It is argued that imperfect approaches to the assessment of investment potential of regions, as well as the shortcomings of strategic planning system for the development of Russian macro-regions, lead to the fact that the state applies the same management decisions to the constituent entities that differ significantly in social and economic potential. The results of the assessment of the investment potential of the FEFD are presented. The need to clarify the used assessment algorithms based on specific factors and conditions of development of certain groups of territories is substantiated. Using the methods of cluster analysis, the typology of the regions of the FEFD was carried out, and the peculiarities of realization of investment potential within 3 clusters of territories were highlighted. The article proposes a differentiated approach to the assessment of investment opportunities of regions, focused on the maximum use of accumulated socio-economic potential for developed regions and the development of priority measures of state support for regions with a limited resource of self-development.
Explosive nucleosynthesis and beyond: Energy generation in supernovae from massive progenitors
Authors: Roy Rupak
Published: June 2024

Massive stars (initial mass ≳10M⊙, where M⊙ is the mass of the Sun) end their life through violent explosions known as core-collapse supernovae, which are supposed to be among the brightest events of the universe. Nucleosynthesis inside the ejecta of such exploding stars was proposed to be the main source of its years-long radiated power. With the advent of timedomain astronomy, brilliant supernovae with longer evolutionary time scales and larger peak luminosities (10-100 times) than canonical supernovae, have been revealed. These are Superluminous Supernovae (SLSNe). The powering mechanisms of SLSNe are yet not resolved. The proposed theories are the interaction of SN-shock with circumstellar medium (CSM), the presence of a spindown magnetar, or pair-instability (PISNe) in very massive stars. Most likely, In the case of SLSNe, these physical processes generate extra radiated power in addition to the radioactive power due to explosive nucleosynthesis inside the ejecta. Here, I review different mechanisms behind the radiated luminosity of supernovae created from massive progenitors.
Theoretical applications to nuclear astrophysics
Authors: Shubhchintak  , Sharma Dinkar
Published: June 2024

Nuclear reaction study is important to understand elemental abundance in the universe and stability of stars. For several reactions due to the paucity of experimental data or diffculties in performing the direct measurements, we depend upon theoretical estimates and therefore one needs reliable theoretical models with minimum inputs. This paper is a short review of our work on nuclear reactions and their applications to astrophysics. In particular, we discuss the nuclear transfer and breakup reaction while focusing on our theoretical modelings and techniques involved.
Nuclear Astrophysics with Exotic Beam; Thick-target Measurements at CRIB
Authors: Yamaguchi H. , Hayakawa S. , Shimizu H. , Okawa K. , Liu F.L. , Zhang Q. , Ma N.R. , Ahn S. , Kim D. , Park C.Y. , Hu J. , Lam Y.H.
Published: June 2024

Astrophysical reactions involving radioactive isotopes (RI) often play an important role in high-temperature stellar environments. The experimental information on those reactions is still limited mainly due to the technical difficulties in producing high-quality and intense RI beams. Although a direct measurement of those reactions at astrophysical energy would be still challenging, we may take several alternative approaches to determine the reaction rates, by applying other mesurement methods or improving the target and detectors. Here we mainly discuss the thick-target method in inverse kinematics (TTIK) based on the successful examples of experimental studies performed at Center for Nuclear Study, the University of Tokyo, using the low-energy RI beam separator CRIB.
Dedicated cautery-enhanced tubular self-expandable metal stent for endoscopic ultrasound-guided hepaticogastrostomy: feasibility study
Authors: Vargas-Madrigal Jorge , Chan Shannon M. , Dhar Jahnvi , Teoh Anthony Y.B. , Samanta Jayanta , Lakhtakia Sundeep , Giovannini Marc
Published: June 2024

Background Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is an alternative for biliary drainage in patients with obstructive pancreaticobiliary pathology when endoscopic retrograde cholangiopancreatography (ERCP) is not feasible. Despite its effectiveness, EUS-HGS is associated with a significant risk of adverse events. This study aimed to evaluate the feasibility and safety of a newly designed dedicated cautery-enhanced tubular self-expandable metal stent (SEMS) for EUS-HGS.

Methods This multicenter prospective study included patients with malignant biliary obstruction in whom ERCP had failed because of tumor infiltration, inability to drain the intrahepatic ducts, or surgically altered anatomy. A dedicated cautery-enhanced tubular SEMS was used for EUS-HGS. Technical and clinical success rates, procedure times, and adverse events were evaluated.

Results 20 patients underwent EUS-HGS with the dedicated stent. Technical and clinical success rates of 100% were achieved, with no reported severe adverse events or mortality. The median procedure time was 16 minutes. Recurrent biliary obstruction was observed in 1 patient.

Conclusions The dedicated cautery-enhanced tubular SEMS for EUS-HGS can simplify the procedure and enhance its safety and efficacy. This innovation shows promise for improving patient outcomes, although further studies are needed to validate these findings in a broader patient population.
Aneurisma de arteria cubital y síndrome del martillo hipotenar
Authors: García Nieto Beatriz , Ki Yoo Young Woon , Escolano González Laura , Pastor Alconchel Laura , Bernardos Alcalde María Concepción , Marzo Álvarez Ana Cristina
Published: June 2024

El síndrome del martillo hipotenar es una patología vascular poco frecuente que produce una degeneración aneurismática de la arteria cubital a su paso por el canal de Guyon. Se suele dar en trabajadores expuestos a microtraumatismos de repetición en eminencia hipotenar; por ello, algunos autores lo consideran una enfermedad profesional. La clínica varía según el tamaño del aneurisma y la inestabilidad de su contenido. Para el diagnóstico, es necesario realizar una adecuada anamnesis y exploración física del paciente, así como tener un elevado índice de sospecha. Su tratamiento varía desde el médico conservador hasta la cirugía reconstructiva, dependiendo de la permeabilidad y de la integridad vascular del arco palmar. Se presenta un caso clínico de varón de 67 años con aparición de tumoración pulsátil dolorosa en eminencia hipotenar tras realizar trabajos de reforma. Mediante angiorresonancia, se confirmó la sospecha clínica, y se procedió a la resección del aneurisma parcialmente trombosado con posterior reconstrucción arterial.
Gathering Dust—Resistance to Simulator-based Deliberate Practice in Microsurgical Training
Authors: Temple-Oberle Claire F. , Harrop A. Robertson , Webb Carmen E. , Somerville Susan G.
Published: June 2024

Background Despite unrestricted access to a simulated microsurgery model, learners have not consistently self-regulated their learning by completing practice. This paper explores the lived experience of learners regarding how practice is perceived and why it is resisted.

Methods A qualitative study was conducted, including recorded and transcribed focus groups and semistructured interviews. First and second pass coding was conducted by one reviewer, with feedback from another. Transcripts were analyzed with a constant comparative approach customary to thematic analysis. Theory was engaged to help explain and support the findings.

The study was undertaken at the University of Calgary plastic surgery residency training program in Calgary, Alberta, Canada, involving 15 informants (9 residents and 6 surgeons).

Results Four themes emerged: (1) barriers to practice, (2) motivation to practice, (3) owning learning/solutioning, and (4) expectations of practice. Competing priorities and time constraints were barriers. Motivation to practice ranged from extrinsic (gaining access to the next course) to intrinsic (providing optimal patient care). Learners described a range of ownership of learning and depth of effort at solutioning of practice opportunities. Learners expressed high expectations around model fidelity, ease of setup, and feedback. Learners self-regulating their learning, with surgeons acculturating practice at work, can overcome some barriers. As per self-determination theory (SDT), learners need explicit linkage to how the task aligns with their goals. Assessment may be required to motivate learners. In respect of adult learning theory, homework needs to be allocated by a respected trainer. Modeling simulation practice may encourage adult learners. Finally, the tenets of deliberate practice (DP) need to be explained in order that learners can optimize their practice time.

Conclusion Microsurgical simulation practice is valued but barriers exist that invite resolution. Assisting residents to overcome barriers, maintain motivation, take ownership, and assimilate DP will help improve their microsurgery practice.
Pseudoaneurisma traumático del arco palmar superficial: A propósito de un caso clínico
Authors: Garrido Ferrer Jose Felix , Cabanes Ferrer Isabel , Gazquez Gazquez Gemma , Marco Díaz Laura , Hernández Ferrando Lorenzo
Published: June 2024

Introducción El pseudoaneurisma traumático del arco palmar es una patología poco frecuente, con un manejo diagnóstico y terapéutico controvertido.

Reporte de Caso Presentamos el caso de un varón de 39 años que, tras una lesión incisocontusa en la eminencia tenar de la mano izquierda, desarrolló un pseudoaneurisma del arco palmar superficial. Se decidió realizar un estudio con angiotomografía y se planteó el tratamiento quirúrgico: ligadura y resección de la patología vascular.

Discusión Los traumatismos vasculares requieren un seguimiento de sus posibles complicaciones. La unión de la exploración física y de la alta sospecha diagnóstica permite el manejo terapéutico de la lesión. Hasta ahora, el tratamiento quirúrgico es el que aporta mejores resultados a corto y largo plazos.
Reconstrucción no biológica del ligamento colateral cubital de la articulación metacarpofalángica del pulgar: Un estudio retrospectivo de casos y controles
Authors: Barrera-Ochoa Sergi , Martínez-Garza Julio Adrian , Pereira-Cavaca Rita , Prieto-Mere Jose , Mendez-Sanchez Gerardo , Soldado Francisco
Published: June 2024

Objetivo El objetivo de este análisis retrospectivo fue cotejar los resultados posoperatorios de la reconstrucción ligamentosa no biológica (RLNB) para lesiones crónicas que involucran la articulación metacarpofalángica (AMCF) y el ligamento colateral cubital (LCC) del primer dedo.

Materiales y Métodos En total, 18 pacientes con lesión de la AMCF fueron sometidos a una reconstrucción ligamentosa estática no biológica y se incluyeron en este análisis retrospectivo de casos y controles. Se compararon las mediciones preoperatorias, posoperatorias y del pulgar contralateral (evaluación clínica, radiografías y cuestionarios de resultados subjetivos) durante una media de 38 meses de seguimiento.

Resultados Para la RLNB, la media de rangos de movimiento posoperatorios de las AMCF y de las articulaciones interfalángicas del pulgar fueron de 0 a 57,5° y de 0 a 71°, respectivamente. Las fuerzas promedio de agarre y pinza, en relación con la mano no afectada, fueron de 103,3% y 88,7%, respectivamente. Todos los pacientes demostraron estabilidad con un punto final firme en relación con el pulgar no afectado. La puntuación media en la versión corta del cuestionario de Discapacidades de Brazo, Hombro y Mano (Quick Disabilities of the Arm, Shoulder and Hand, QuickDASH, en inglés) entre todos los pacientes fue de 11,9 para el módulo de discapacidad/síntoma, 0 para el módulo de deportes, y 16,5 para el módulo de trabajo. Se informó rigidez en cuatro pacientes, y ningún paciente sufrió problemas relacionados con la herida u otras complicaciones.

Conclusión La RLNB del LCC del pulgar genera buenos resultados a corto plazo, lo que puede permitir una recuperación y rehabilitación aceleradas.
Differences and interactions between banks’ financial statements and prudential regulation
Authors: Mérő Katalin , Tardos Ágnes
Published: June 2024

The article analyzes the dichotomy between banks' financial statements and prudential regulatory requirements. While financial statements should be true and fair, prudential regulatory requirements focus on banks' soundness, riskiness and risk management practices. The lessons learned from the 2008 crisis have brought about significant changes in both bank accounting and banking regulation, which have led to a major transformation in both areas. Their development is characterized by a number of contradictions, differences and mutual interactions. In this article, we analyze three areas of European bank accounting and regulation that were of particular relevance to the 2008 crisis and the subsequent regulatory changes, and which are crucial for both today's bank accounting and banking regulation. These are as follows: the differences in the application of fair valuation of financial instruments; the issue of impairment accounting; and the differences in equity and regulatory own funds. We have identified different patterns of interaction across the three areas and have identified a number of areas for further research.
The generalized strong subadditivity of the von Neumann entropy for bosonic quantum systems
Authors: De Palma Giacomo , Trevisan Dario
Published: June 2024

We prove a generalization of the strong subadditivity of the von Neumann entropy for bosonic quantum Gaussian systems. Such generalization determines the minimum values of linear combinations of the entropies of subsystems associated to arbitrary linear functions of the quadratures, and holds for arbitrary quantum states including the scenario where the entropies are conditioned on a memory quantum system. We apply our result to prove new entropic uncertainty relations with quantum memory, a generalization of the quantum Entropy Power Inequality, and the linear time scaling of the entanglement entropy produced by quadratic Hamiltonians.
Automatic JOREK calibration via batch Bayesian optimization
Authors: Crovini E. , Pamela S. J. P. , Duncan A. B. ,   JOREK Team
Published: June 2024

Aligning pedestal models and associated magnetohydrodynamic codes with experimental data is an important challenge in order to be able to generate predictions for future devices, e.g., ITER. Previous efforts to perform calibration of unknown model parameters have largely been a manual process. In this paper, we construct a framework for the automatic calibration of JOREK. More formally, we reformulate the calibration problem into a black-box optimization task, by defining a measure of the discrepancy between an experiment and a reference quantity. As this discrepancy relies on JOREK simulations, the objective becomes computationally intensive and, hence, we resort to batch Bayesian optimization methodology to allow for efficient, gradient-free optimization. We apply this methodology to two different test cases with different discrepancies and show that the calibration is achievable.
Vertically hierarchical electro-photonic neural network by cascading element-wise multiplication
Authors: Cong Guangwei , Yamamoto Noritsugu , Kou Rai , Maegami Yuriko , Namiki Shu , Yamada Koji
Published: June 2024

Integrated photonic neural networks (PNNs) usually adopt traditional convolutional neural network (CNN) or multilayer perceptron (MLP) network models. These models consist of horizontally cascaded deep layer architectures interleaved by nonlinear activation functions. However, there are practical challenges for on-chip realizing such architectures, including the optical loss and the lack of efficient on-chip optical activation nonlinearity. Here, we propose a vertically hierarchical photonic neural network leveraging electro-optical element-wise multiplication to extract an element-wise feature in a polynomial projection space, which enables high-accuracy classification. For this network architecture, the light propagates through only two fully connected linear layers; thus, vertical extension to the deep layer is not limited by optical loss. This electro-photonic network can perform equivalently to or outperform optical CNN and MLP models even without interleaving deep layers by activation functions, benchmarking ∼97.9%, ∼87.7%, and ∼90.3% average blind-testing accuracies, for the whole test sets of MNIST handwritten digits, Fashion-MNIST images, and KMNIST Japanese cursive characters, respectively. It also demonstrates a >99% accuracy for boundary prediction of 12-labeled clusters. This work presents a different PNN architecture, which offers both high performance and better amenability to an integrated photonics platform.
Reconciling calculations and measurements of inverse bremsstrahlung absorption
Authors: Turnbull D. , Katz J. , Sherlock M. , Milder A. L. , Cho M. S. , Divol L. , Shaffer N. R. , Strozzi D. J. , Michel P. , Froula D. H.
Published: June 2024

It was recently shown that the use of Coulomb logarithms appropriate for bremsstrahlung radiation (rather than transport processes) along with corrections for the Langdon effect and ion screening reproduced measurements of collisional absorption in well-characterized underdense plasmas [D. Turnbull et al., Phys. Rev. Lett. 130, 145103 (2023)]. However, it was recognized at the time that the use of the standard absorption-reduction factor from Langdon's seminal paper was inconsistent with the use of Coulomb logarithms that are thermally averaged over a Maxwellian electron-velocity distribution function. A more accurate approach would be to average over the expected super-Gaussian distribution function while accounting for the Gaunt factor's velocity dependence, which somewhat mitigates the Langdon effect; however, at that time, this theory matched the data less well. This conflict is now eliminated with the additional insight that the ionization state of our mid-Z ion species (when present) was lower than had been assumed, as evidenced by the Thomson-scattering data and time-dependent Cretin simulations. We are now able to show that an improved treatment of the Langdon effect provides the best match to data. Otherwise, the prior conclusions remain unchanged. We also show an example of the substantial expected impact to the absorption rate in calculations of indirect-drive hohlraums.
Nucleation dynamics of a model biomolecular liquid
Authors: Wilken Sam , Gutierrez Juan , Saleh Omar A.
Published: June 2024

Liquid–liquid phase separation in biology has recently been shown to play a major role in the spatial control of biomolecular components within the cell. However, as they are phase transitions, these processes also display nontrivial dynamics. A model phase-separating system of DNA nanostars provides unique access to nucleation physics in a biomolecular context, as phase separation is driven near room temperature by highly thermo-responsive DNA hybridization and at modest DNA concentrations. By measuring the delay time for phase-separated droplets to appear, we demonstrate that the dynamics of DNA nanostar phase separation reflect that of a metastable binary mixture of patchy particles. For sufficiently deep temperature quenches, droplets undergo spinodal decomposition and grow spontaneously, driven by Brownian motion and coalescence of phase-separated droplets, as confirmed by comparing experimental measurements to particle-based simulations. Near the coexistence boundary, droplet growth slows substantially, indicative of a nucleation process. The temperature dependence of droplet appearance times can be predicted by a classical nucleation picture with mean field exponents and demonstrates that a theory previously used to predict equilibrium phase diagrams can also distinguish spinodal and nucleation dynamical regimes. These dynamical principles are relevant to behaviors associated with liquid–liquid phase separating systems, such as their spatial patterning, reaction coupling, and biological function.
Impact of contact rotation on the vacuum arc root movement
Authors: Li Zhengbo , Fu Si , Cao Yundong
Published: June 2024

This paper aims to investigate the dynamic characteristics of vacuum metal vapor arcs under rotating and traditional direct contact separation modes. Non-symmetrical pure copper electrodes with an anode radius of 7.5 mm and a cathode radius of 22.5 mm are employed in the experiments. The permanent magnet actuator provides an average opening speed of 1.0 m/s for cathode direct separation and 1–3 deg/ms for rotation. Results show that electrode rotation significantly influences the distribution and motion speed of the arc root on the cathode surface.
Self-excited flapping motion of wall-mounted valvular leaflets in a three-dimensional channel flow
Authors: Wang J. , Nitti A. , de Tullio M. D.
Published: June 2024

The onset of flow-induced oscillations in valve-like configurations remains not completely understood, despite the wide relevance in fluid transport across human physiology and various industrial applications. The present work explores the excitation mechanisms of self-sustained oscillation with key operating parameters in a general-purpose configuration by means of high-fidelity simulations. The investigation is carried out with a partitioned framework that resolves the fluid field by a finite-difference fractional step scheme, discretizes the structural domain via an isogeometric method, and considers an immersed boundary forcing through the interpolation/spreading kernel built by moving-least squares. Our findings confirm the onset of flapping motion in valvular shells, jointly influenced by geometric parameters, structural properties, and flow conditions. Specifically, at a Reynolds number (Re) of 800 and shell aspect ratio of 1.0, a critical reduced velocity exists at around 6, bifurcating static and periodic oscillation modes. After this criterion, flexible shells flutter in the third-plate-mode natural frequency, with oscillation amplitudes approaching an asymptotic value, coupled with intensified vortex shedding, as the reduced velocity increases. Re mainly imparts a destabilizing effect on the fluid-shell system; a lower Re suppresses flow-induced vibrations through viscous dissipation, while a higher Re introduces three-dimensional complexities, asymmetrical oscillations, and quasi-periodicity in the flapping dynamics, especially within the critical regime of reduced velocity. The impact of shell aspect ratio is intricate; in contrast, the case with an aspect ratio of 1.3 displays more intensive flapping motion compared to the reference case of 1.0, whereas further increasing to 1.6 mainly shows stabilizing effects in the shell dynamics.
Plasmon induced ambipolar photoresponse in Au decorated MoS2/PEDOT:PSS nanocomposite films
Authors: Arjun K. , Amaljith C. K. , Karthikeyan B.
Published: June 2024

Here, a photodetector based on Au decorated MoS2/poly(3,4-ethylenedioxythiophene) poly(4-styrenesulfonate) PEDOT:PSS nanocomposite films (NCFs) were prepared and their ambipolar (negative and positive) photoresponse under UVC (220–300 nm) and UVA (320–400 nm) UV illumination by increasing the Au decoration on MoS2 in NCFs was reported. This unusual phenomenon relates to the confinement and trapping of charges induced by radiation and plasmons. The hydrothermal technique is employed for generating MoS2 nanosheets. Optical studies reveal the observable bandgap difference resulting from the addition of increasing Au decoration on MoS2 in NCFs. Fourier transform infrared spectroscopy investigations are conducted to comprehend the vibrational characteristics of the produced samples. Carrier localization and trapping generated by photoexcitation and plasmon-induced ambipolar photoresponses provide a versatile control parameter. These results provide opportunities for the application of NCF material in electrical, optical, and optoelectronic devices. The results of this work broaden the pool of potential materials for UVC and UVA photodetectors, perhaps providing new perspectives on the photoresponse of the NCF.
Pattern transition of flow dynamics in a highly water-absorbent granular bed
Authors: Otoguro Kojiro , Yoshii Kiwamu , Sumino Yutaka
Published: June 2024

An aqueous sodium chloride solution was injected at a controlled rate into a granular bed in a quasi-two-dimensional cell. The granular bed was made of dried, highly water-absorbent gel particles whose swelling rate was controlled by the salinity of the injected fluid. At a high salinity level (low swelling rate), high injection rate, and short timescale, the injected fluid percolated between the gel particles in an isotropic manner. Meanwhile, at a low salinity level (high swelling rate), low injection rate, and long timescale, the gel particles clogged the flow path, resulting in anisotropic branch-like structures of the injected fluid front. The transition of the injection pattern could be understood based on the ratio of the characteristic timescales of swelling and injection. Moreover, the clogged pattern showed an oscillatory pressure drop whose amplitude was increased with higher salinity. Such an oscillatory behavior observed in an injection process in swelling gel particles may be relevant in geological situation, such as fluid migration underground.
Session 2. Oral Presentation for: Aligning stars: making LNG imports happen in Australia
Authors: Wilson Perry
Published: June 2024

Presented on Tuesday 21 May: Session 2 We present the inputs and results of a discounted cash flow model which details the requirements for an import terminal to eventualise. The key requirement is high certainty cash flows from foundation users. This can be made possible through capacity booking which can be potentially underwritten by governments to ensure security of supply during peak winter months. The out-chartering of the floating storage and regasification unit (FSRU) to serve as a liquefied natural gas (LNG) carrier during the peak northern winter will provide an additional revenue source. We also analyse the legacy supply decline and various price setting mechanisms for the southern states which will soon turn net importers. We will describe the status of the four projects in the pipeline and identify milestones. We conclude that an import terminal provides an alternative proposition in the southern states considering the highly seasonal demand profile, the decline of Gippsland Basin production, and the relative inflexibility of coal seam gas. Further, FSRUs can be redeployed to other regions, which reduces stranded asset risk from pipeline expansions, given Australia’s net zero targets. To access the Oral Presentation click the link on the right. To read the full paper click here
Session 3. Oral Presentation for: The case for integrated IMR programs: increasing operational efficiency with a holistic approach that reduces risk and carbon emissions
Authors: Henney Ka
Published: June 2024

Presented on Tuesday 21 May: Session 3 This paper discusses the positive impact of adopting an integrated, customisable inspection, maintenance, and repair (IMR) approach when addressing subsea assets. Primary focus and expenditure are typically committed to the design, planning, and engineering of infrastructure. Of paramount importance, but often overlooked, are the ongoing health checks required of the subsea assets. These activities are regularly left until an issue is found, production is affected, or subsea asset data is required to enable decision making to ensure the lowest level of risk and maximise uptime. How the operations and maintenance approach used for subsea assets is best addressed using an integrated philosophy that streamlines not only contract management, but the collection and analysis of data is detailed. By supporting a more holistic view of assets not only by field, but regionally and globally, operators are best positioned to apply advanced technologies including machine learning for the development of risk-based inspection programs that provide insight into potential failures and anomalies. Building and adopting truly optimised IMR programs also reduces vessel days by leveraging already deployed assets, advanced technologies, and remote piloting to complete varied inspection tasks simultaneous to other ongoing operations, lowering emissions and risk associated with mobilisations and personnel on board. The impact of optimised inspection planning on users’ in-house resources is detailed. With internal experts dealing with IMR planning, analysis, and data management often stretched, adopting this forward-thinking approach to IMR has the potential to alleviate the burden associated with targeted planning and clearing backlogs that manage risk. To access the Oral Presentation click the link on the right. To read the full paper click here
Session 5. Oral Presentation for: A feasibility study of Boree Salt body mapping in the Adavale Basin using passive seismic data
Authors: Talukder Asrar
Published: June 2024

Presented on Tuesday 21 May: Session 5 Hydrogen plays a pivotal role in the global energy transition and may require underground storage. So far salt cavern storage is the only proven technology for underground hydrogen storage. The Boree Salt in the Adavale Basin, mostly at depths from 1 to 2.5 km and up to 550 m thick, consists predominantly of halite and is deemed suitable for hydrogen storage. However, current maps are inadequate. Recently passive seismic data (ambient noise) have received much interest for subsurface imaging. The main signal from passive data is surface waves (usually below 2 Hz). The capability of surface waves for the Boree Salt body mapping is examined. Parameters of seismic sensor spacing, the dominant frequencies of the surface waves, and data noise levels are all considered. It is demonstrated that surface waves from ambient noise can map the Boree Salt bodies with a survey distance of ~40 km. Between frequencies of 0.12 and 0.25 Hz, results from the latter have better resolution because of a shorter wavelength. Moving to higher frequencies of 0.5 and 1 Hz, however, the resolution becomes worse, because the depth sensitivity of surface waves moves to the shallower part of the model with increasing frequencies, rendering them incapable of effectively probing the targeted depths. For signal/noise ratio above five, station spacing can be as large as 1 km without compromising quality. Therefore, cost-effective and environmentally friendly passive seismic data can be a good alternative to the traditional active-source data for deep salt body imaging. To access the Oral Presentation click the link on the right. To read the full paper click here
Session 12. Oral Presentation for: The ongoing transformational journey of Australia’s oldest and largest oil and gas operation
Authors: Burger Tom
Published: June 2024

Presented on Wednesday 22 May: Session 12 For over 50 years Gippsland Basin Joint Venture (GBJV) has been producing oil and gas from the Gippsland Basin. Through hard work, challenging the status quo and innovation, the business, the operation and the people have been on a transformational journey. You may have heard about our conventional expansion opportunities, Kipper-Tuna-Turrum development and Longford Gas Conditioning Plant, but have you heard about how GBJV is progressing carbon dioxide (CO2) to sales with BOC and Air Liquide or how the team has reduced flare by 46% since 2018? Have you heard how the team increased Longford’s capacity by 11% in 2022 to deliver the highest gas production since 2017 to meet market demand. Or about how we are transforming the operation through our Gippsland Asset Streamlining Project, where we will no longer have a Crude Stabilisation Plant or a Gas Plant 1 at Longford? We continue to focus on our reliable gas operation through upcoming projects such as Hastings Generation Project, and Kipper Compression Project while also pursuing meaningful reductions in greenhouse gas emissions such as South East Australia Carbon Capture and Storage Project in the Gippsland Basin. Our transformation to a ‘Modern Australian Gas Business’ has not only meant change for our facilities but also change for our people in how we work and the culture we have built. Every day, our teams work to supply essential energy to Australian homes and businesses while also being on a transformational journey to improve the sustainability of our operation and contribute to the energy transition. To access the Oral Presentation click the link on the right. To read the full paper click here
Session 12. Oral Presentation for: Leadership and talent attraction and retention – an existential risk to our industry
Authors: Hastie Scott
Published: June 2024

Presented on Wednesday 22 May: Session 12 Political, social, shareholder – and increasingly talent – pressure is driving a seismic shift as oil and gas operators are required to transform into diversified energy companies. Attracting and retaining the required leadership and talent to drive this transformation is an existential risk to our industry. 10.5% of the total workforce left the industry during the 2019/2020 oil price crash. Since 2020 the experienced oil and gas industry workforce has aged and will take critical skills and experience with them into retirement. 40% of Australian oil and gas recruiters believe retaining this knowledge and replacing these skills are the industry’s biggest challenges. In parallel, events in August 2023 in Western Australia have demonstrated the immediate market impact workforce unrest can have. Concurrently, it is becoming harder to attract talent to the industry. The competition for adaptive leaders and high-skilled workers has been accentuated as the oil and gas sector continues to evolve and now competes for these skills sets with other industries. Environmental, Social and Governance (ESG) performance is increasingly becoming an important factor in the industry’s ability to attract and retain talent. In a recent global talent index report, 85% of respondents stated ESG is a factor in whether they will stay or leave an oil and gas organisation. Interestingly, 55% of those open to switching sectors would be interested in switching to renewables. In this paper, I provide oil and gas companies with pragmatic guidance on how to quantify the impact of these challenges, adapt the industry narrative, and re-position as an employer of choice. To access the Oral Presentation click the link on the right. To read the full paper click here
Session 14. Oral Presentation for: Australia’s gas markets: similar problems…similar solutions?
Authors: Gibb John
Published: June 2024

Presented on Wednesday 22 May: Session 14 Declining supply and entrenched demand in all three of Australia’s domestic gas markets – the East Coast, Western Australia (WA) and the Northern Territory (NT) – is creating similar issues. We tend to think of these as essentially separate, disconnected and divided by vast swathes of land. But the reality is that scarce local supply has been sanctioned in all three markets – despite around 16 tcf being sanctioned for export as liquefied natural gas (LNG) – and domestic demand remains resilient, as per both Australian Energy Market Operator (AEMO) and Wood Mackenzie forecasts. Starting with the largest, the increasingly tight East Coast market continues to hit headlines as it deals with supply crises, government interventions and new regulations. Undersupplied, underinvested and underexplored, it is also divided by activism and state and federal politics. Traditionally more sedate, the WA market has slowly drifted in a similar direction. New forecasts highlighting potential gas shortages have sparked more state intervention in the market, including banning LNG exports by certain suppliers. The NT market might be the smallest, but it’s ahead of the curve, already experiencing emergency upstream shortages that sparked increased domestic supply from LNG exporters. While there is a less diverse range of supply sources in the NT, the answer to current shortages matches the options currently being looked at by regulators on both coasts. To access the Oral Presentation click the link on the right. To read the full paper click here
Session 14. Oral Presentation for: Goldilocks dilemma: lower cost, more supply, reduced emissions, and reliable trading partner. What is the outlook for Australia getting the gas balance just right?
Authors: Paull Matt
Published: June 2024

Presented on Wednesday 22 May: Session 14 Australia’s east and west coast domestic gas markets are physically and geographically separated. Each Australian gas market has followed a different trajectory, with the west being defined by large liquefied natural gas (LNG) projects, a relatively small domestic market, and a long-standing domestic gas reservation that historically ensured the domestic market was oversupplied and prices remained low. The east coast market instead relied for decades on supply from the Cooper and Gippsland basins which only supplied the domestic market, with both now in decline. The establishment of LNG export capacity in Queensland connected the east coast market to international markets for the first time and was followed by bans and moratoriums on gas development in some jurisdictions. Notwithstanding their very different history, both markets now face potential domestic supply shortages within a decade, and both have experienced government intervention in the past 12 months. Government’s stated aims are to lower prices, ensure ongoing investment in supply, reduce emissions, and continue LNG exports. This paper examines forecast supply and demand, the impact of government intervention, net zero policies and the importance of maintaining Australia’s export reputation as a reliable supplier. Getting this balance just right will require a challenging ‘Goldilocks moment’, with serious consequences if we get it wrong. To access the Oral Presentation click the link on the right. To read the full paper click here