bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical simulations of propane pool fires with the EDC / finite rate chemistry approach using global reaction mechanisms
Authors: Thabari Jeri At , Maragkos Georgios , Kruljevic Boris , Snegirev Alexander , Moorthamers Youk , Merci Bart
Published: November 2024

Large-eddy simulations (LES) of propane gaseous pool fires with the eddy dissipation concept (EDC) combustion model, considering finite rate chemistry effects, are presented in this study. Two global (2-step) chemical reaction mechanisms for propane are explored with different grid resolutions. The study aims to investigate the performance of the employed approach towards predicting the flow field, the flame temperature, and the concentration of minor species (carbon monoxide). The selected mechanisms are also studied in mixture fraction space using a 0D CMC code to complement the LES simulations. The results demonstrate minor differences between the two mechanisms for the predicted flame temperature and the resulting flow field. Nevertheless, the production of CO was significantly different between the two mechanisms. In addition, the numerical predictions on coarse grids were strongly grid sensitive and could not accurately resolve the flame dynamics, illustrating the increased grid requirements associated with the use of finite rate chemistry.
Study of a fire in a tunnel during construction phase
Authors: Leclerc Côme , Mehaddi Rabah , Acem Zoubir , Masselin Bertrand , Boulet Pascal
Published: November 2024

In this paper the propagation of smoke was studied experimentally and numerically in a tunnel during excavation, considering that the tunnel was closed on the side of the Tunnel Boring Machine, with no specific ventilation system to control the smoke. The analysis of the results focused on the smoke layer in the gallery and the plume at the tunnel exit on the access shaft side, identifying smoke-free zones that could facilitate access by emergency services. The presence of an external wind above the shaft was seen to disturb the flow at the exit, possibly also affecting the smoke flow in the tunnel.
Enhancing high-resolution fuel maps in WUI areas: El Pont de Vilomara fire, a case study
Authors: Śanchez P. , González I. , Cortés A. , Margalef T. , Carrillo C.
Published: November 2024

A precise understanding of the spatial distribution of fuels and buildings at high resolution is crucial for analysing, modelling, and predicting fire behaviour in Wildland-Urban Interface (WUI) areas. However, the challenging and costly nature of estimating and mapping forest fuel attributes presents obstacles to global efforts in creating high-resolution fuel maps. This work addresses these limitations by proposing a strategy to generate high-resolution fuel maps based on the 1 km resolution FirEUrisk fuel map and transforming it into an enriched 20 m resolution fuel map, incorporating constructions and water masks. For simulation purposes, the forest fire spread simulator FARSITE has been used. The proposed enhanced downscaling strategy has been tested on a forest fire that occurred in July 2022 in the village El Pont de Vilomara in Catalonia (north-east of Spain). This work highlights how detailed mapping can significantly improve the precision of forest fire simulations, especially in WUI areas. The higher resolution fuel map provides a more accurate representation of fire behavior (SC 0.8 vs. 0.7) while maintaining the same fire detection (POD) as the unchanged fuel map but significantly reducing false alarms (lower FAR). This improvement contributes to proactive fire prevention strategies and ensures an immediate and effective emergency response.
Development of large lab-scale fire dynamics experiments relevant for Scandinavian wildfire behaviour
Authors: Aamodt Edvard , Jiang Lei , Fjellgaard Mikalsen Ragni , Olav Snersrud Dag , Vermina Plathner Frida , Sjöström Johan , Rosnes Magne , Synnøve Skilbred Ellen
Published: November 2024

The Scandinavian countries have in later years seen several severe wildfires and is expected to exhibit more severe fire danger. While direct flame spread has been an important topic in wildfire research, there is a need for development and to ensure that experimental methods are relevant for Scandinavian wildfire characteristics. To ensure relevant lab conditions for fire-resilient material development work, large lab-scale (2×4 meters) experiments were conducted on various fuels. Its fire behaviour (such as rate of spread, fireline intensity and flame length) was compared with ongoing wildfire field studies from ongoing field studies in boreal and hemiboreal Sweden. The lab fire experiments show good potential to mimic relevant natural wildfire conditions in the laboratory once a standard design fire exposure for fire resilient materials is developed.
A full-scale experimental study of oxygen reduction systems for ASRS applications
Authors: Kostka S , Xin Y
Published: November 2024

Full-scale experiments were conducted to determine the limiting oxygen concentration for fire propagation (LOCFP) required to protect Automated Storage and Retrieval Systems (ASRS). The LOCFP is a key parameter for any Oxygen Reduction System (ORS) installation and represents the maximum oxygen concentration allowed to provide protection in a facility. The LOCFP is dependent on the material properties, environment, geometry and ignition conditions. Previous full-scale experiments have been conducted for typical warehouse storage arrangements represented by FM Global standard commodities. As warehouses increasingly shift to ASRS, factors such as smaller flue space and container geometry can affect the LOCFP. The current study utilized an enclosure in which a 7-tier high 2×2 array of mini-load ASRS (ML-ASRS) was ignited using a premixed burner to evaluate flame propagation at reduced oxygen levels. The adequate LOCFP was defined by the extent of fire propagation contained within the fuel array over the ignition duration. Results show that geometry has noticeable effects on the LOCFP, and increasing the quantity of participating material around the ignition area tends to lower the LOCFP. In contrast to previous work, where the external material was the main factor affecting the LOCFP, ASRS applications are quite sensitive to the internal contents that play a major role in the fire propagation. Corrugated products stored within the ML-ASRS containers reduce the oxygen concentration required for protection relative to plastic commodities alone. The LOCFP values of the internal contents generally aligned with values previously found for their respective standard commodities.
Study of the cooling of a metal plate at high temperature by water spraying
Authors: Cappon Laurine , Mehaddi Rabah , Beji Tarek , Acem Zoubir
Published: November 2024

Experiments to cool a steel plate at high temperature by spraying water droplets were carried out using four different nozzles (TG-SS1, TG-SS3, TG-SS5, TG-SS10), in order to assess their effectiveness. Two plate thicknesses were studied. The surface temperature was measured at several points positioned diagonally on the plate: in the centre, near the edge and in between, using K-type thermocouple wires welded directly to the surface of the plate with a separate contact. This technique ensures accurate temperature measurement throughout the cooling process. The spray nozzles have been characterised to obtain an average droplet velocity Vmean
and a Sauter mean diameter (D
32). Prior to spraying, the plate was heated by a radiant panel to reach steady-state temperatures, ranging from 120°C to 650°C. During cooling, the plate continued to be heated by the radiant panel. Heat flux (

Q
˙

) and heat transfer coefficient (HT C) were calculated from the temperature data. It was found that high levels of critical heat flux (MW.m−2
) were achieved in the centre of the plate, ranging from 0.86 MW.m−2
, for the TG-SS1 nozzle to 3.58 MW.m−2
, for the TG-SS10 nozzle. In the same time, the convective heat transfer coefficient also reached high values ranging respectively from 5.5 kW.m−2.K−1
(TG-SS1 nozzle) to 27 kW.m−2.K−1
(TG-SS10 nozzle). It was concluded that the mass flux of water is the parameter with the greatest influence on cooling efficiency.
A pilot study of vision-based real-time detection of invisible gas leak and fire
Authors: Duong Dana , Ko Yoon
Published: November 2024

The detection of gas leak/fire is a critical element in the safe production, transportation, storage and dispensing of many industrial gases including hydrogen. A novel background detection methodology for IR-insensitive gases was explored in this work. This methodology extracted IR data to a certain target frequency and processed to filter the background signals of the adjacent air and inverse the movements of gas in comparison to the background pixels. Results from the IR data indicate that the background detection methodology is possible and visually outperforms the native FLIR HSM filter. The methodology was capable of capturing both hot-gas and cold-gas flow. Due to the nature of the methodology, detection limits were found to be ΔT∼30 °C for cold-gas helium and ΔT∼20 °C for hot-gas helium, with better ability to detect as the temperature differences increase.
Virtual experiments yield comparable results to physical experiments on evacuation decision-making
Authors: Balboa Adriana , Cuesta Arturo , Alvear Daniel
Published: November 2024

Virtual Reality (VR) is fast becoming a key instrument in research on human behaviour in fire. However, reports on the validity of results produced by VR are very limited. In this study we conducted virtual experiments on evacuation decision making, which were later replicated in a real environment. Results of the two sets of experiments (6 trials each) were then compared. We found no significant differences between responses of participants in the virtual experiments and participants in the physical experiments. The results are consistent with recent findings attesting to the possibility to conduct realistic experimentation through VR environments while retaining confidence in the resulting data.
Assessing the Impact of Bjørnis the Fire Bear: A Study on Fire Safety in Norwegian Households
Authors: Fjellgaard Mikalsen Ragni , Siren Fjærestad Janne , Fredagsvik Nora , Nergård Annette , Steen-Hansen Anne
Published: November 2024

The present research explores the influence of Bjørnis the Fire Bear on residential fire safety in Norway. Our survey, comprising 1275 participants, reveals that Bjørnis spurred the adoption of 5181 fire safety measures among the respondents, averaging 4.1 measures per household. The data suggests a positive association between exposure to Bjørnis and an increased number of safety measures implemented. These results highlight Bjørnis’ efficiency in fostering awareness about fire safety, potentially serving as a model for introducing or sustaining similar mascots and initiatives on a global scale.
Sense-making of Fire Safety Deemed-to-Satisfy Solutions in the Modern Built Environment
Authors: Mohan A T , Seligmann B , Van Coile R , Lange D
Published: November 2024

Fire safety has long been delivered under the assumption that the use of deemed-to-satisfy (DtS) solutions results in specifications for buildings which are appropriately safe in the event of fire. This has the consequence that regulatory compliance can be achieved through the application of DtS solutions without further deliberation, or (in a performance-based regime) through the comparison of the performance of a performance-based design with that of a DtS design. However, recent research, recent incidents, emerging technologies, methods and materials of construction should have the fire engineering community questioning the suitability of DtS solutions. This article highlights potential limitations of DtS solutions from the perspective of developing a fire safety strategy. Specific emphasis is placed on the changing context of fire safety given the rising complexities in modern buildings. The changing context is conceptualised using a sense-making device called the Cynefin framework. A view through the Cynefin lens highlights the need for a deliberative and critical approach to the adoption of DtS solutions considering: (i) the challenges of identifying the non-linear cause-and-effect relationships, especially taking into account changing contexts; (ii) the impact of knee-jerk rulemaking i.e., the introduction of rules in the absence of supporting theoretical knowledge.
Numerical simulations of short-range wildfire firebrand exposure to industrial cylindrical storage tank
Authors: Dossi S , Planas E , Pastor E
Published: November 2024

Increasing wildfire frequency and intensity indicate the need for improved wildfire Quantitative Risk Assessment (QRA) methodologies for industrial components. Firebrand exposure, the leading cause of infrastructure wildfire ignition, has not been considered in wildfire QRA frameworks. This paper proposes a methodology to simulate and quantify firebrand contact exposure to an industrial storage tank using the Fire Dynamics Simulator (FDS). A low aspect-ratio cylindrical tank obstacle is exposed to constant Lagrangian particles flux (2.5 particles m−2s−1) under varying wind speeds (4ms−1, 7ms−1 and 10ms−1), with varying particle densities (50 kgm−3, 100 kgm−3 and 300 kgm−3). Constant-mass spherical particles simulate firebrands. The highest firebrand landing densities occur at the tank and floor intersection, in two regions located perpendicular to wind direction, and at the tank’s windward recirculation zone edge. The highest landing densities are reached with highest wind speed tested, and with 100 kgm−3 particle density, reaching 7 times the inlet flux in [particles m
−2
]. The highest firebrand amount that reaches the storage tank roof, especially vulnerable to ignition, occurs at 10 ms−1 wind with the lowest particle density tested (50 kgm−3). Results allow quantification of firebrand contact exposure around an industrial critical component; contributing to future comprehensive wildfire NaTech QRA methodologies.
The effectiveness of low-pressure water mist systems on battery fire extinguishing
Authors: Kraus-Namroży Natalia , Brzezińska Dorota , Brzezińska Maria , Brzeziński Mateusz
Published: November 2024

Due to the increase in areas of Li-ion battery use, their fire prevention and protection aspects have become an urgent need. This article presents real-scale battery fire tests and the effectiveness of low-pressure water mist systems on battery package extinguishing. The experiments show that battery fire can lead to an uncontrolled increase in temperature, jet flamming, or explosion, but water mist installation can decrease the temperature of the modules and control the fire propagation.
Timber crib fuel source of BS 8414 testing method
Authors: Chotzoglou Konstantinos , Fateh Talal
Published: November 2024

Since Grenfell Tower tragedy in 2017, the timber fire source and the design details of an External Wall System (EWS) specified in BS 8414 have received a lot of criticism. The present study deploys a multi-scale test series for evaluating the timber crib source of the BS 8414 and providing data for benchmarking the heat generated and façade exposure in the test method. Wood’s thermal characterization is investigated using results obtained from a bomb calorimeter test (ISO 1716) at different moisture levels. On a large scale, tests are undertaken to evaluate the crib fire characteristics in both free-burn and within the BS 8414 combustion chamber built with an inert façade extending above. The timber cribs are placed on a balance under an oxygen calorimetry hood measuring mass loss and heat release rate. Measurements included temperature within the chamber and the incident heat flux in front of the crib and on the inert façade. Good repeatability was observed, and reproducibility was compared against historical data and ongoing studies at European level. The exposed surface of the façade received high-intensity heat flux levels, enough for igniting different materials. Benchmarking data of this study may assist scientific and advisory committees in standardization and regulatory levels to enhance the safety of high-rise buildings.
Spectral analysis of radiation emitted by flames from several liquid and solid fuels
Authors: Parent Gilles , Erez Giacomo , Boulet Pascal
Published: November 2024

This paper focuses on the analysis of radiation emitted by flames fueled by diesel, kerosene, heptane, polyurethane foam, and wood, conducted at a medium scale. The emitted radiation was studied using a Fourier Transform InfraRed (FTIR) spectrometer covering the wavenumber range of 700 - 5500 cm−1 (corresponding to the wavelength range of 1.82 - 14.3 μm). In addition, opacity measurements were performed at different wavelengths (410, 520, 785, 1650, and 3800 nm) using laser beams passing through the flames. The optical thickness was plotted against wavelength, and two different behaviors were observed. For kerosene, diesel, and PU foam, the optical thickness showed a characteristic straight line on a log-log scale, which is typical of soot, as their optical properties follow an inverse power law with wavelength. Heptane and wood showed significantly lower optical thickness, consistent with their lower soot production. Their optical thickness does not follow a straight line on a log-log scale. Transmittance measurements were used to calculate the equivalent flame emissivity at different wavelengths, which allowed an equivalent flame temperature to be derived by fitting the intensity spectrum with a 1D model of radiation emitted by a homogeneous isothermal column.
Test protocols and criteria for PV roofs fire behaviour characterization
Authors: Cancelliere Piergiacomo , Manzini Giovanni , Traina Giombattista , Parolini Fabio
Published: November 2024

The increasing number of photovoltaic (PV) installations leads to a more significant consideration of the fire risk associated with the photovoltaic modules’ installation. Given the importance and interest of all stakeholders in fire safety, both internationally and nationally, a process focused on fire risk assessment and mitigation has been started. This paper focuses on photovoltaic systems applied on residential and industrial building rooftops that are not integrated into the roof tiling (BAPV). Fires triggered directly by the photovoltaic system or where the photovoltaic system is involved could occur on these installations. This paper outlines an experimental campaign developed for assessing the fire risk of photovoltaic installations on roofs. The fire experiments and the test rigs proposed have been developed starting from current international and European regulations. Furthermore, considering the European specifications for construction products, the research program carried out proposes new test protocols and fire behaviour rating criteria of the photovoltaic modules coupled with building roofs system of. The fire rating criteria for PV and building’s roof are based on some of the main calorimetry variables already used in the European building products reaction to fire classification (THR – Total Heat Release, FIGRA – FIre Growth RAte). The actual novelty of these protocols lies in testing the PV module and roofing material samples as a single specimen. Such configuration permits the assessment of the interaction between building roofs and PV modules as a whole in case of fire. Test protocols and fire criteria are resumed also in the Italian standard CEI TS 82-89:2023 based on this work.
Detecting urban fires after the 2024 Noto Peninsula Earthquake using satellite data
Authors: Iwami T
Published: November 2024

The 2024 Noto Peninsula Earthquake caused an urban fire in Wajima City, Ishikawa Prefecture. Fire detection using satellite data has been considered mainly for forest fires. In this paper, we attempt to detect fires in urban areas. In fire detection using infrared satellite data, we showed that it is possible to detect urban fires using existing fire detection algorithms, while in the fire detection using SAR satellite data, the technology for forest fires cannot be directly used for urban fires because of the different reflectance characteristics of the target. We compared the fire area inside and outside the burned area of an urban fire and clarified the differences in reflectance characteristics. Then, detection of urban fire areas was conducted using deep learning. Although the trial was conducted with limited data, it was confirmed that the detection could be done with high accuracy.
Analysis of the Exitation Dynamics in 2D Semiconductor Nanostractures Induced by a Quantum Electromagnetic Field Under the Kerr Phase Modulation
Authors: Tereshchenko I A , Tikhonova O V
Published: November 2024

The peculiarities of the excitation in planar nanostructures induced by a nonclassical field under the impact of cross phase modulation are analyzed. The possibility to controllably enhance a certain excitation channel by varying field frequency detuning from resonance is demonstrated. The effect of formation of entangled two mode field states similar to the Schrodinger’s cat state under the influence of the cross-phase modulation is revealed. The influence of the correlated two mode squeezed vacuum field state is studied and the effect of enhancement of even excitation channels due to photon correlations in the field modes is found. The obtained results open new prospects to control the hybrid electron-photon systems and to develop a fully quantum photon-matter interface on the basis of the 2D nanomaterials.
Degenerate bound states in the continuum in a grating waveguide: Method of infinite-grating eigenmodes vs numerical Rigorous Coupled Wave Analysis (RCWA)
Authors: Reynolds Cole , Kocharovsky Vitaly
Published: November 2024

We reveal the origin and describe properties of degenerate bound states in the continuum which appear when a conventional symmetry-protected bound state in the continuum meets a leaking waveguide eigenmode. A degenerate bound state in the continuum emerges due to a destructive interference of two crossing, non-leaking odd-parity and leaking even-parity, infinite-grating eigenmodes experiencing parity symmetry breaking at their crossing point.
Channel Separation of Secondary Generated Radiation in Atomic Gases Irradiated by Orthogonal XUV and Infrared Pulses
Authors: Romanov A A , Silaev A A , Sarantseva T S , Flegel A V , Vvedenskii N V , Frolov M V
Published: November 2024

Based on the numerical solution of the three-dimensional time-dependent Schrödinger equation, we calculate the secondary generated radiation induced by hydrogen atoms in linearly polarized extreme ultraviolet (XUV) and intense infrared (IR) pulses. We show that XUV-induced channels of secondary generated radiation (second harmonic of the XUV pulse and XUV-assisted high-order harmonic generation) can be well separated at the orthogonal geometry of two pulses by polarization measurements. It is demonstrated that at the orthogonal geometry the accuracy of IR-field retrieving based of XUV second harmonic generation can be significantly increased in comparison with the case of collinear geometry, for which the XUV-assisted HHG channel interferes with the XUV second harmonic generation.
Quantum correlations and laser threshold
Authors: Papoff Francesco , Lippi Gian Luca , D’Alessandro Giampaolo , Oppo Gian-Luca
Published: November 2024

We present a model of nanolasers that includes the effect of all two-particle quantum correlations. We find that the lasing starts with a finite coherent amplitude and that lasing and non-lasing solutions coexist.
Nonlinear coherent modes and atom optics
Authors: Yukalov V.I. , Yukalova E.P. , Bagnato V.S.
Published: November 2024

By pumping energy into a trapped Bose-Einstein condensate it is possible to generate nonlinear coherent modes representing non-ground-state condensates. A Bose-condensed system of trapped atoms with nonlinear coherent modes is analogous to a finite-level atom considered in optics which can be excited by applying external fields. The excitation of finite-level atoms produces a variety of optical phenomena. In the similar way, the generation of nonlinear coherent modes in a trapped condensate results in many phenomena studied in what is termed atom optics. For example, there occur such effects as interference patterns, interference current, Rabi oscillations, harmonic generation, parametric conversion, Ramsey fringes, mode locking, and a dynamic transition between Rabi and Josephson regimes. The possibility of creating mesoscopic entangled states of trapped atoms and entanglement production by atomic states in optical lattices are studied.
Ghost vortices and how to turn them real
Authors: Chaika Andrii , Richaud Andrea , Yakimenko Alexander
Published: November 2024

Ghost vortices represent a unique class of topological excitations in quantum fluids, and are notoriously difficult to investigate because they are located in regions where superfluid density is low. In this work, we introduce a controlled platform for generating and observing these elusive vortices. By inducing rotation in an imbalanced mixture of two-component Bose-Einstein condensates (BECs), we create necklaces of real vortices in the majority component, with cores populated by particles from the minority component. The wavefunction associated to the state of the latter is characterized by the presence of ghost vortices. These ghost vortices exhibit an arrangement mirroring their real counterparts, forming a “dual” ghost-vortex necklace, and play a crucial role in sustaining the overall dynamics of the mixture. Additionally, we propose an experimental approach for directly observing ghost vortices in an ultracold mixture of 23Na + 39K. Through a controlled quenching of the inter-component scattering length, expelled atoms from vortex cores diffuse and swirl around unpopulated phase singularities, enabling their direct observation.
Condensates Breaking Up Under Rotation
Authors: Dutta S , Lode A U J , Alon O E
Published: November 2024

The ground state of a rotating Bose-Einstein condensate trapped in a two-dimensional anharmonic–anisotropic potential is analyzed numerically at the limit of an infinite number of particles. We find that the density breaks up along the x direction in position space and along the py
direction in momentum space together with the acquisition of angular momentum. Side by side, the anisotropies of the many-particle position variances along the x and y directions and of the many-particle momentum variances along the py
and px
directions become opposite when computed at the many-body and mean-field levels of theory. All in all, the rotating bosons are found to possess unique correlations at the limit of an infinite number of particles, both in position and momentum spaces, although their many-body and mean-field energies per particle and densities per particle coincide and the condensate fraction is 100%. Implications are briefly discussed.
Influence of core coupling on spectral characteristics of 7-core Yb-doped fiber laser with fs-inscribed FBGs
Authors: Kuznetsov Alexey G. , Wolf Alexey A. , Egorova Olga N. , Semjonov Sergey L. , Dostovalov Alexander V. , Podivilov Evgeniy V. , Babin Sergey A.
Published: November 2024

Multicore fiber (MCF) is treated now as a perspective medium for high-power fiber lasers. Here we report on the point-by-point femtosecond (fs) inscription of highly-reflective fiber Bragg grating (FBG) array in all cores of 7-core Yb-doped fibers. By using such complex mirror, we achieved high-power laser generation at a wavelength of 1064 nm in two types of active MCF with different core-to-core distance. At cladding pumping by a 976-nm laser diode of 50 W power, both the MCFs with FBG cavity generate nearly the same output power of up to 33 W, but the laser spectra behave principally different since the generation of the cores is almost independent or strongly coupled in these two cases. To study the effect, we develop analytical model and perform its experimental verification identifying the role of core coupling and FBG characteristics on the generated mode and its spectrum. It is shown that the coupling of the MCF cores leads to the formation of supermodes and their hybridization when reflected from an array of highly-reflective FBGs in a resonator, therefore generation occurs with the same spectrum in all cores, despite the significant difference in the central wavelengths and the shape of the reflection spectra of individual FBGs.
Ontology of Addressed Fiber Bragg Structures as a New Type of Sensor Elements
Authors: Morozov O G , Zh Sakhabutdinov A
Published: November 2024

Addressed Fiber Bragg Structures (AFBS) serve a dual purpose, acting as complex-sensitive elements with two distinct configurations: one involving two Fiber Bragg Gratings (2λ-AFBS) with different Bragg frequencies, and the other employing a single FBG with two π-phase shifts (2π-AFBS). The difference frequency between these configurations acts as the unique AFBS address, which remains constant regardless of the measured physical fields. Additionally, they function as a two-frequency laser radiation source capable of operating in both reflection and transmission modes, corresponding to the structure above. When the difference frequency is unique for each AFBS, it enables self-multiplexing of sensors. In this article, we present the ontology of AFBS, encompassing parent structures with 2λ- or 2π-components and their successor AFBS with three spectral components. These structures offer various combinations of difference frequencies, both symmetrical and asymmetric, allowing them to address and convert information signals to the low-frequency range while also mitigating collisions caused by the relative shifts of structures’ spectra during measurements. We also explore the subjects of interrogation for these structures and discuss their calibration, as well as the future prospects of AFBS development, including the usage of hybrid AFBS.
Nuclear Astrophysics Using Laser-Driven Neutrons
Authors: Hayakawa Takehito
Published: November 2024

Progress in laser physics has enabled us to produce various particles such as electrons, photons, and ions from high field plasma generated from the interaction between high power laser and materials. Neutrons could be generated by nuclear reactions on the second target behind the first target. At present, it is possible to generate neutrons with a flux of up to 1011 neutrons/shot. These neutrons are suitable for the study of nuclear astrophysics. We present the perspective and the present activity for the application to the nuclear astrophysics.
Inverse problem-solving method applied to acoustic characterisation of a thin film using Debye series model
Authors: Manoochehrnia Pooyan , Marechal Pierre , Leduc Damien , El-Kettani Mounsif Ech-Cherif
Published: November 2024

In this paper, it is proposed to solve an inverse problem with the perspective of determining the ultrasonic properties (thickness, longitudinal wave velocity, density and attenuation coefficient) of a thin epoxy resin film deposited on a glass substrate with well-known properties. The question focuses on finding acoustic parameters of the structure and the transducer thanks to a numerical implementation of a physical model matching the experimental ultrasonic response. The Debye Series Model (DSM) has been used to model the structure. A step by step procedure is implemented where at each step one parameter is estimated by minimizing the MSE (Mean Square Error) between simulated model and experimental signal. Estimated parameters are checked to be physically viable. At beginning an initial set of parameters are announced together with related waveforms and at the end the final adjusted parameters are presented beside finally obtained waveforms.
Acoustic radiation force generated by vortex beams on microbubbles embedded in a soft hydrogel
Authors: Penneron Antoine , Brunet Thomas , Baresch Diego
Published: November 2024

Acoustical tweezers are recently developed experimental tools that enable the contactless manipulation of a wide range of particles in fluid media. Their good penetrability, high trapping strength and biocompatibility have poised these acoustic methods as interesting alternatives to other well established optical and magnetic manipulation techniques. This work describes preliminary steps in the development of an active approach to measure the local elasticity of soft hydrogels using single-beam acoustical tweezers. The displacement of a microbubble embedded in a hydrogel is induced by the acoustic radiation force of a focused vortex beam. Microbubbles approximately 100 µm in size can be displaced by a few microns in soft hydrogels with a typical shear modulus ranging from 10 to 100 Pa, consistent with a radiation force in the micronewton range. The applied force can be modelled using resolved measurements of the spatial properties of the incident pressure field. Using a simple elastic model for the bubble motion in the medium, the net displacement enables the experimental estimation of the applied force. We find a relatively good quantitative agreement between the radiation force model and our experimental discussion. Possible reasons for the discrepancies are discussed. Overall, the proposed approach presents real benefits compared to other conventional methods to assess the mechanical properties of soft and fragile materials, as it can be considered minimally intrusive, local, and well-adapted to probe thick and opaque-to-light materials in bulk.
Development of multichannel readout electronics system for MWPC of heavy ion radiotherapy
Authors: Xiong Jianfei , Zhou Rong , Pu Guocui , Zhang Xiang , Wang Zhonghai , Pu Yuehu
Published: November 2024

A customized Multi-Wire Proportional Chamber (MWPC) was developed for beam monitoring in heavy ion radiotherapy at West China Hospital of Sichuan University. We designed a miniaturized readout electronics module to ensure the device is compact and lightweight enough to fit into the treatment head. Each module is equipped with 13 DDC316 chips and a Field Programmable Gate Array (FPGA) to process 200-channel signals from the MWPC, including charge integration, digital-to-analog conversion, beam spot localization, and an optical module to enable 100-meter signal transmission from the module to the Irradiation Control System (ICS). Test results show that the linearity of the readout data is better than 1% over the dynamic range of charge input from 60 fC–12 pC. The relative energy resolution of electronics is about 4.87% at a minimum input charge of 60 fC. The test results illustrate that the positional resolution is better than 0.1 mm after channel conformance correction with a MWPC, utilizing a 30 mm diameter X-ray beam at an energy of 19.5 keV.
Introduction
Authors: Naha Souvik
Published: November 2024

This book delves into the complex interplay between cricket and various socio-political dynamics in the twenty-first century. It examines how cricket, as a widely beloved sport, influences and reflects identity politics, nationalism, and state authority across different regions, including South Asia, Australia, Western Europe, Southern Africa, and North America. By analyzing the sport’s role in shaping national identity and providing a platform for expressing national aspirations, the book offers a unique perspective on global identity politics. It also explores how cricket facilitates the negotiation of gender, sexual, ethnic, and racial identities, making it a significant medium for understanding modern societal structures and interactions.
Brand It Like Ben Simmons
Authors: Heenan Tom
Published: November 2024

Since its inception in 2011, the Big Bash League (BBL) season has been extended to meet broadcaster and public demands. The competition now colonizes much of Australia’s cricketing and holiday seasons, pushing Test, Sheffield Shield, and the fifty-over format to the margins. Unlike these traditional formats, the BBL targets non-cricket fans, notably families and ‘theatre-goers’, who want a compact three-hour entertainment package rather than a drawn-out, five-day Test match. This development is reflected in how cricket is increasingly played and marketed. The older generation, raised on traditional formats, is giving way to a younger ‘theatre-goer’ set, clad in franchise’s merchandise and wanting the full BBL package. Allegiances to the national team now compete with loyalties to franchised brands. As these loyalties intensify, fuelled by marketers, Test cricket’s schedule will be further reduced and the Sheffield Shield sidelined, as the interests of players, Cricket Australia (CA), and the media align to profit from the BBL. Its abbreviated format, coupled with growing media rights deals, will enable players to extend their careers and contracts. Longer seasons will provide media outlets with more content, which, unlike cricket’s longer formats, are better suited to primetime TV. While free-to-air and pay-TV broadcasters will attract higher advertising rates and subscriptions, Cricket Australia will profit from leasing franchises and growing media rights deals. This new reality was etched on the face of the young Stars supporter whose tears symbolized his love of the franchise, and the growing corporatization and Americanization of the Australian cricket market.
Nationalism on the ‘Back Foot’ but Still Not Out
Authors: McCree Roy
Published: November 2024

Cricket has been an integral component of West Indian nationalism, identity, and anti-imperialism since the early twentieth century. Invariably, West Indian cricket and cricketers came to represent these lofty ideals, as well as a form of symbolic political capital, whose principal raison d’être was not just to resist historical modes of domination but also to project West Indian sovereignty, empowerment, and unity across its various islands and ethnic groups. Against this background and based on documentary sources (notably media reports and official reports on West Indies cricket), this chapter has two major objectives. Firstly, it examines how the commercialization of cricket in the region through the emergence of the T20 format in 2013, fashioned along the lines of American franchise sport, has provided a context for destabilizing as well as reinforcing the notions of nationalism, national, and regional identity symbolized by the game. Secondly, it analyses the tensions arising from the participation in T20 cricket by West Indian players and playing for the regional West Indies cricket team, which has caused the players to be accused of surrendering political consciousness for ‘cash consciousness’. Drawing on the work of Bourdieu, exploring T20 cricket in the West Indies provides an opportunity to examine this clash between cricket as symbolic political capital and cricket as economic capital, which speaks to how the format has served to reflect, reinforce, and disrupt the traditional political construction of the game in an era when it has become much more commercialized and globalized.
Political Mapping
Authors: Leonard-Fleckman Mahri
Published: November 2024

Chapter 3 begins to explore textual representations by examining political maps and boundary descriptions of the Iron Age Shephelah. These maps have played a powerful role in archaeological and historical debates about identity and have retained a powerful hold in the Western political imagination. Because ancient Gath is left out of these political maps, the chapter focuses on ancient Timnah as its borders are represented in the books of Joshua and Chronicles, and in Sennacherib’s campaign in the Assyrian Royal Annals. The chapter argues that the distinct visions of economic and political control of the Shephelah in these different representations reveal a creative scribal conversation and literary artistry, though not historical accuracy, of political control in the region in the Iron Age. In other words, textual representations about Iron Age Timnah tell us less about Timnah than about the scribal art of re-presenting it politically.
A similar coast effect of geoelectric field directions in a three-block boundary zone during geomagnetic storm pulses
Authors: Xin Zhang , De Santis Angelo , Perrone Loredana , Xiaoping Wu
Published: November 2024

The coast effect, which enhances the geoelectric field during geomagnetic pulses at the sea-land boundary, is a classic topic in geomagnetism. This paper focuses on a similar coast effect observed at the boundary zones of three tectonic blocks, i.e. Alax, Ordos, and Tibetan. We used multiple geoelectric field data of the block boundary zone to obtain the surface current density and charge accumulation during two geomagnetic storm pulses in 2015. Then, we calculated the amplitudes of Spherical Elementary Current Systems (SECS) and telluric currents using the Markov Chain Monte Carlo method. The results indicate that the polarized directions of induced charges and currents are perpendicular to the block boundaries and tend to point towards the interior of the Tibetan block. Additionally, the Parkinson vectors of geomagnetic pulses point towards regions with lower surface resistivity. The amplitude of telluric currents at a depth of 10 km is one of the three SECS at 110 km, which locates sources in the boundary zone between Alax block and Tibetan block. Similar to the coast effect in the sea-land boundaries, we identify an analogous phenomenon in three-block boundary zone, demonstrating the accumulation of induced currents and charges during geomagnetic storm pulses. This study provides a novel empirical basis to promote our understanding of geomagnetic storm pulses induced charges enhancements at discontinuous conductivity interfaces on the Earth.
“My Lungs Are Better, but Now My Back Hurts.”: Back Pain after Pneumonia
Authors: Shivers Joseph P. , Standaert Christopher J.
Published: November 2024

The evaluation of all patients with low back pain (LBP) should include consideration of “red flag” conditions, including infection, such as vertebral osteomyelitis. Infection can be challenging to identify, as many people present with indolent pain and no fever. Some historical features that place individuals at higher risk for infection include intravenous drug use, diabetes mellitus, immunosuppression, rheumatic disease, alcoholism, liver failure, renal failure, a recent bacterial infection, and the presence of an indwelling venous catheter. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are excellent screening tests. If elevated, urgent/emergent blood cultures and imaging with plain X-ray and a magnetic resonance imaging (MRI) are indicated. If inconclusive, it may be necessary to repeat these in 2 weeks. All patients with apparent vertebral osteomyelitis should be evaluated by an infectious disease specialist and a spine surgeon. Most patients are managed nonoperatively with antibiotics, ideally following identification of the causative organism.
“I’m Really Scared.”: Acute Back and Leg Pain with Incontinence
Authors: Reitman Charles
Published: November 2024

Cauda equina syndrome (CES) is a clinical diagnosis representing dysfunction of the nervous system at the cauda equina. Symptoms include bowel and bladder dysfunction, sensory changes, and possible loss of distal motor function in the lower extremities. Patients often report pain in the back, buttocks, and/or lower extremities, but not always, and the hallmark features are the signs and symptoms related to neurological deterioration. Acute or subacute onset CES is almost always due to a relatively abrupt compression of the thecal sac, generally from conditions including but not limited to disc herniation, epidural hematoma, tumor, or infection. MRI is the imaging study of choice to confirm compression of the cauda equina. Progressive loss of neurological function is an emergency, and evaluation and treatment should proceed without delay. At acute presentation, hold diet and anticoagulation medications until a definitive treatment plan is established, as emergency surgery is likely needed.
“I Was Hurt at Work, and I’ll Get Hurt Again if I Go Back.”: Back Pain and Workplace Injury
Authors: Barber Kristina , Standaert Christopher J. , Brakke Holman Rachel
Published: November 2024

Low back pain (LBP) is the second most common reason for short-term disability claims and the most common reason for long-term disability claims in the United States. It is often nonspecific with no red flag symptoms. Absent concerns for significant pathology like fracture or neurologic loss, imaging of the lumbar spine tends to show expected age-related changes and is unlikely to alter an initial recommendation of nonsurgical, noninvasive care. Coping with LBP has more to do with psychosocial confounders inside and/or outside the workplace than the magnitude of pain itself. Most injured workers will improve and return to work, so identifying risk factors for deviation from this expected pattern is important. There are many health-related, work-related, and systems-related factors predicting failure to return to work that should be identified.. While engaged in active treatment including physical therapy, light duty is recommended to promote return to work and mitigate psychosocial comorbidities.
“I Go on This Golf Trip Every Year, but It Hurts to Swing a Club.”: Back Pain and Golf
Authors: Bires Seth , Standaert Christopher J. , Jayabalan Prakash
Published: November 2024

Low back pain (LBP) is one the most common injuries seen in professional and recreational golfers, accounting for 25% of all golf injuries. Multiple factors are linked to the increased risk of LBP in golfers, including the repetitive nature of the golf swing, carrying a golf bag, and individual demographics and physical characteristics. The management of LBP in golfers involves integrating an understanding of LBP and spine pathology, in general, with the biomechanics of the golf swing. A golf swing uses a wide range of musculature throughout the body and exposes the lumbar spine to significant compressive and torsional forces. Specific to golfers, history should include previous LBP with golf and the amount of general and golf-specific activity the patient performs on a regular basis. Treatment involves the introduction of exercise and skill training to improve the mechanics and performance of an individual’s swing and to improve overall fitness.