bluuebunny/crossref_metadata_2025_split huggingface dataset:
2D chemical evolution models
Authors: Spitoni E. , Cescutti G. , Recio-Blanco A. , Minchev I. , Poggio E. , Palicio P. A. , Matteucci F. , Peirani S. , Barbillon M. , Vasini A. 
Published: December 2023

Context. According to observations and numerical simulations, the Milky Way could exhibit several spiral-arm modes of various pattern speeds, with the slower patterns located at larger galactocentric distances.
Aims. Our aim is to quantify the effects of the spiral arms on the azimuthal variations in the chemical abundances of oxygen and iron and for the first time of neutron-capture elements (europium and barium) in the Galactic disc. We assume a model based on multiple spiral-arm modes with different pattern speeds. The resulting model is an updated version of previous 2D chemical evolution models.
Methods. We apply new analytical prescriptions for the spiral arms in a 2D Galactic disc chemical evolution model, exploring the possibility that the spiral structure is formed by the overlap of chunks with different pattern speeds and spatial extent.
Results. The predicted azimuthal variations in abundance gradients are dependent on the considered chemical element. Elements synthesised on short timescales (i.e. oxygen and europium in this study) exhibit larger abundance fluctuations. Moreover, for progenitors with short lifetimes, the chemical elements returned to the ISM perfectly trace the star formation perturbed by the passage of the spiral arms. The map of the star formation rate (SFR) predicted by our chemical evolution model with multiple patterns of spiral arms presents arcs and arms compatible with those revealed by multiple tracers (young upper-main sequence stars, Cepheids, and the distribution of stars with low radial actions). Finally, our model predictions are in good agreement with the azimuthal variations that emerged from the analysis of Gaia DR3 GSP-Spec [M/H] abundance ratios, if at most recent times the pattern speeds match the Galactic rotational curve at all radii.
Conclusions. We provide an updated version of a 2D chemical evolution model capable of tracing the azimuthal density variations created by the presence of multiple spiral patterns. We show that elements synthesised on short timescales exhibit larger abundance fluctuations.
Numerical solutions to linear transfer problems of polarized radiation
Authors: Janett Gioele , Benedusi Pietro , Riva Fabio 
Published: December 2023

Context. A relevant class of radiative transfer problems for polarized radiation is linear, or can be linearized, and can thus be reframed as linear systems once discretized. In this context, depending on the considered physical models, there are both highly coupled and computationally expensive problems, for which state-of-the-art iterative methods struggle to converge, and lightweight ones, for which solutions can be obtained efficiently.
Aims. This work aims to exploit lightweight physical models as preconditioners for iterative solution strategies to obtain accurate and fast solutions for more complex problems.
Methods. We considered a highly coupled linear transfer problem for polarized radiation, which we solved iteratively using a matrix-free generalized minimal residual (GMRES) method. Different preconditioners and initial guesses, designed in a physics-based framework, are proposed and analyzed. The action of preconditioners was also computed by applying GMRES. The overall approach thus consists of two nested GMRES iterations, one for the original problem and one for its lightweight version. As a benchmark, we considered the modeling of the intensity and polarization of the solar Ca I 4227 Å line, the Sr II 4077 Å line, and the Mg II h&k lines in a semi-empirical 1D atmospheric model, accounting for partial frequency redistribution effects in scattering processes and considering a general angle-dependent treatment.
Results. Numerical experiments show that using tailored preconditioners based on simplified models of the considered problem has a noticeable impact, reducing the number of iterations to convergence by a factor of 10–20.
Conclusions. By designing efficient preconditioners in a physics-based context, it is possible to significantly improve the convergence of iterative processes, obtaining fast and accurate numerical solutions to the considered problems. The presented approach is general, requiring only the selection of an appropriate lightweight model, and can be applied to a larger class of radiative transfer problems in combination with arbitrary iterative procedures.
Accretion in the recurrent nova T CrB: Linking the superactive state to the predicted outburst
Authors: Zamanov R. , Boeva S. , Latev G. Y. , Semkov E. , Minev M. , Kostov A. , Bode M. F. , Marchev V. , Marchev D. 
Published: December 2023

Context. T CrB (NOVA CrB 1946) is a famous recurrent nova with a recurrence timescale of 80 years.
Aims. We aim to estimate the colours, luminosity, and mass-accretion rate for T CrB (NOVA CrB 1946) during and after the superactive state.
Methods. We performed and analysed UBV photometry of the recurrent nova T CrB.
Results. For the hot component of T CrB, we find average dereddened colours of (U − B)0 = −0.70 ± 0.08 and (B − V)0 = 0.23 ± 0.06, which correspond to an effective temperature of 9400 ± 500 K and an optical luminosity of 40 − 110 L⊙ during the superactive state (2016–2022). After the end of the superactive state, the hot component became significantly redder, (U − B)0 ≈ −0.3 and (B − V)0 ≈ 0.6 in August 2023, and its luminosity decreased markedly to 20 − 25 L⊙ in April–May 2023, and to 8 − 9 L⊙ in August 2023. The total mass accreted during the superactive state from 2014 to 2023 is ∼2 × 10−7 M⊙.
Conclusions. This is a significant fraction of the mass required to cause a thermonuclear runaway (TNR). Overall our results support a model in which a large accretion disc acts as a reservoir with increased accretion rate onto the central white dwarf during disc high states, ultimately leading to a TNR explosion, which now seems to be imminent.
From “them” to “us”?
Authors: Yu Mandy Hoi Man , Feng Dezheng (William) 
Published: December 2023

Abstract
This study provides an account of how the representation of China has changed diachronically in the South China
Morning Post (SCMP), the leading liberal English-language broadsheet in Hong Kong, since the sovereignty
transfer in 1997. Adopting a corpus-based approach to critical discourse studies, we analyse two corpora of news reports about China in the
newspaper, one for 1997–2000 and the other one for 2015–2018. It is found that the representation of China has changed from very negative
representations focusing on human right problems in the first period to largely positive representations centring upon China’s global and
economic power in the second period. The changes may suggest that the SCMP has to a certain extent shifted its positioning
of China from “them” to “us”, though an ambivalent stance is observed. The ambivalence is discussed in relation to the economic convergence
and political divergence between Hong Kong and the Chinese mainland.
On the link between grammaticalization and subjectification
Authors: Nuyts Jan 
Published: December 2023

Abstract
This article argues that the widespread view that the diachronic processes of grammaticalization and of
subjectification go hand in hand, and that highly subjectivized meanings typically correlate with highly grammaticalized forms,
should be revised. The point is made on the basis of the case of the diachrony of the Dutch modal verbs. Corpus data show that
four of these verbs recently got involved in a process of collective re-autonomization, while the two other modals in the language
do not. This correlates with differences in the semantic development of the verbs: the four re-autonomizing verbs do, but the two
outliers do not show a regular process of (inter)subjectification. The paper unravels through which mechanisms the grammatical and
the semantic developments may correlate, hence why highly subjectivized meanings do not necessarily like a grammatical status.
Building information modelling-based life cycle assessment (BIM-LCA) for housing estates in Thailand
Authors: Inharwararak P , Stravoravdis S 
Published: December 2023

Abstract
Climate change is an important issue with rapidly increasing significance. The demand for housing is rising every year and this can lead to more carbon emissions and environmental impact from the residential sector. Carbon emission over the whole lifecycle of a building are key for sustainability and BIM can play an important role in assisting designers and stakeholders for better decision making, from design to operation, in order to reduce these emissions and improve efficiencies. This research focuses on BIM-LCA at the early design stages with a proposal for BIM-LCA implementation for housing in Thailand, where no formal process for this currently exists. It reviews relevant processes from other countries and proposes a framework for implementation for Thailand. It argues that the government, organisation firms and those involved in Thailand’s construction industry should be more aware of problems surrounding global warming and the importance of sustainably designing housing in Thailand from construction in order to reduce the impact to the environment.
An Experimental Investigation on A Simple Direct-Drive Wavepower Generation System Utilising an Oscillating Water Column
Authors: Omar Mohamad Alif , Shokri Shakir , Zakaria Nurul Mardhiyah , Mukhtar Azfarizal , Yusoff Mohd Zamri 
Published: December 2023

Abstract
This study investigates the performance potential of a simple direct-drive wavepower generation system utilising an oscillating water column (OWC). The OWC was selected due to their ability to operate in places with low wave power density, low wave height, and shallow water. This is owing to the fact that the average wave power in the Malaysian sea has been just 8.6 kW/m, which is quite low compared to other coastal nations that use wave energy technology. In this study, the OWC has been scaled down and utilised for laboratory experiments. The experiment is divided into two different parts, which are Procedure A and Procedure B. Procedure A is to determine the maximum wave height (cm), air pressure differential (psi), and upward air speed (m/s) without the air turbine installed. Procedure B, on the other hand, employs a different type of bottom profile to calculate the voltage output (V), current output (A), and power output (W). The results indicated that circular-bottomed sloped seabed is superior, as they can generate the greatest amount of electricity, approximately 0.0105 W, at air speeds of 1.3-2.0 m/s and wave heights of 4-5 cm. The findings suggested that wave energy can be harvested to operate an air turbine, but more research is needed to figure out how to convert wave energy efficiently in Malaysia, where the wave heights are smaller.
A Review: Various Designs of Radial Flux Permanent Magnet Generator Technologies
Authors: Mostaman Nur Afiqah , Sulaiman Erwan , Jenal Mahyuzie 
Published: December 2023

Abstract
In a renewable energy system, the amount of power generated by a renewable energy source constantly evolves. Furthermore, with the smart energy approach, small distributed renewable energy can be included into an industrialized network, enabling real-time optimization, and enabling communication with other facilities. A magnetic generator is one of the renewable energies that use the permanent magnet. As a result, this generator generated magnetic flux power by using the permanent magnetic field. An overview of the radial flux permanent magnet generator for small industry is provided in this study. First, a categorization and in-depth description of radial permanent magnet generators are reviewed. The important features of the permanent magnets are presented, along with their advantages and disadvantages. Additionally, an overview of the most recent machine developments is also presented. Lastly, an overview of the conventional radial flux permanent magnet generator designs that have been used in the development of small-scale generators is as follows.
Design and Simulation of Hybrid Shunt Active Filter for PQ Improvement using PID Genetic Algorithm Controller in 3ϕ-4 Wire System
Authors: Sugavanam K R , Selvaraju P , Chandrika V S , Mohanasundaram K 
Published: December 2023

Abstract
This paper provides an economical solution and advanced method by tuning and optimizing system for power in the transmission line. The proposed system uses PID Genetic Algorithm (GA) controller in three phase four wire system for Total Harmonic Distortion (THD) minimization under balanced load conditions. In this article, traction load model is taken into consideration to evaluate the designed Shunt Active Power Filter (SAPF) for reduction of harmonics in three phase four wire system. Many existing SAPF models were tested using non-linear diode rectifier load for analysis. The GA technique for the reduction of harmonics is used to tune PID parameters such as a proportional (Kp), Integrator (Ki), and Derivative (Kd). In contrast with other controllers such as PI Controller, Fuzzy Logic Controller (FLC), Hysteresis Controller (HC), Sliding Mode Controller (SMC) and Synchronous Reference Frame Theory (SRFT), the performance of the proposed controller is compared. The performance of the designed controller with GA adjusted PID is validated at various loading conditions by comparing it to the performance of the existing system. The outcomes are addressed to demonstrate the effectiveness of the created system.
Performance Analysis of a Cascaded Bidirectional DC-DC Converter for High Current Applications
Authors: Akhtar Mohammad Faisal , Raihan Siti Rohani S , Rahim Nasrudin Abd 
Published: December 2023

Abstract
In this paper, a high-current DC-DC converter with bidirectional capability is presented. The proposed converter topology combines a series capacitor bidirectional converter and a conventional bidirectional converter in a cascaded manner, thus achieving a quadratic voltage gain. The proposed topology is compared with other contemporary high current topologies in terms of voltage gains, component count and conversion efficiency. Furthermore, the converter performance is validated using the Simscape SimPowerSystems toolbox of MATLAB Simulink. It is determined that this topology demonstrated a conversion efficiency of 96% and 98% in step-up and step-down mode respectively, for a 250 W load. Moreover, a current gain of 12.5 was observed in step down mode for a switch duty cycle of 0.4. Lastly, current sharing between inductors and low current ripples were also demonstrated.
Syngas production via dry reforming of methane over Ni/MgO-ZrO2 catalyst
Authors: Farooqi A S , Abdullah B , Hasnain S M W , Farooqi S A 
Published: December 2023

Abstract
This study intended to evaluate the catalytic activity of Ni/MgO-ZrO2 to produce syngas through dry reforming of methane (DRM). The catalyst was prepared by using co-precipitation method followed by impregnation of Ni metal. XRD, BET and FESEM were used to analyze the physicochemical characteristics of the prepared catalyst. A stainless steel vertical reactor fixed with a catalyst bed inside was used to run the DRM process at 800°C, 1 atm and 1:1:1 ratio of CO2:CH4:N2. From the three catalysts studied, Ni/MgO-15%ZrO2 had the maximum conversion for CH4 and CO2 compared to the other two catalysts. The high conversion achieved was because of zirconium oxide. The result obtained from the DRM reaction was further supported by the characterization results, which included average particle size, the morphology of the catalyst, and catalyst peaks.
Energy audit on lighting system for 7-storey educational building – Energy saving opportunity
Authors: Othman Mohd Nezuan bin 
Published: December 2023

Abstract
An energy audit is an important process for determining a building’s energy efficiency. This process includes verification, monitoring and analysis of energy usage and recommending ways to improve energy consumption. This paper presented a study on energy balance, utility system description, methodology to calculate the energy consumption, load apportioning and room data survey on luminance for a 7-storey educational building. The resulting data is then analysed to assess energy performance, identify opportunities for improvement without compromising safety, usability and comfort levels, and suggest potential energy savings measures that can be implemented later. As a result, it shows that the building consumed a total of 669,840.84 kWh of energy over the year of 2016 and 53.64% of the energy usage comes from lighting system. The proposed energy saving measure on lighting system for this building were expected to give 167,873.28 kWh reduction of energy per year by retrofitting an 18 watt and 36 watt of fluorescent lamp to 10 watt and 18 watt of light emitting diode lamp. The room data survey on luminance measurement also shows that 69% of the interior space is overlit, and delamping can result in a total energy savings of 45,550.08kWh per year. Lastly, the total energy saving can also contribute to 116.50 ton/year of CO2 reduction.
Experimental Performance Evaluation on PV-module
Authors: Muharam Azlan , Jalil Zarulrizam Ab , Nor Muhamad Asrul Affendi Mat , Ismail Noor Soudiqqin 
Published: December 2023

Abstract
Photovoltaic (PV) modules are among the most efficient, environmentally benign, and long-lasting systems. The amount of solar radiation impacting these modules that is converted to electricity is quite little. The remaining radiation is transformed into heat, which causes the PV module to overheat and lose efficiency. This experiment examines the effects of changing several operating parameters on the performance of PV modules, including irradiation intensity, and cooling fluid mass flow rate. To reduce cell temperature, a heat exchanger was placed on the PV module’s back surface. For PV modules, findings indicate that as solar cell temperature rises by 1.2°C, the module’s electrical efficiency falls by 5.64%. Meanwhile for PVT, as the temperature of module rises by 1.2°C, the electrical efficiency similarly drops by roughly 0.22%. The solar cell temperature rises by 0.7°C and the output power rise by 2.26W, yet the efficiency falls by 0.25%. In conclusion, the performance of PV modules is greatly influenced by temperature of the solar cell, intensity of solar radiation, and mass flow rate of cooling fluids.
Benchmark thermodynamic analysis of methylammonium lead iodide decomposition from first principles
Authors: Heine Douglas , Yu Hui-Chia , Blum Volker 
Published: December 2023

Abstract
Hybrid organic–inorganic perovskites (HOIPs) such as methylammonium lead iodide (MAPbI3) are promising candidates for use in photovoltaic cells and other semiconductor applications, but their limited chemical stability poses obstacles to their widespread use. Ab initio modeling of finite-temperature and pressure thermodynamic equilibria of HOIPs with their decomposition products can reveal stability limits and help develop mitigation strategies. We here use a previously published experimental temperature-pressure equilibrium to benchmark and demonstrate the applicability of the harmonic and quasiharmonic approximations, combined with a simple entropy correction for the configurational freedom of methylammonium cations in solid MAPbI3 and for several density functional approximations, to the thermodynamics of MAPbI3 decomposition. We find that these approximations, together with the dispersion-corrected hybrid density functional HSE06, yield remarkably good agreement with the experimentally assessed equilibrium between T = 326 K and T = 407 K, providing a solid foundation for future broad thermodynamic assessments of HOIP stability.
Stochastic gradient descent with random label noises: doubly stochastic models and inference stabilizer
Authors: Xiong Haoyi , Li Xuhong , Yu Boyang , Wu Dongrui , Zhu Zhanxing , Dou Dejing 
Published: December 2023

Abstract
Random label noise (or observational noise) widely exists in practical machine learning settings. While previous studies primarily focused on the effects of label noise to the performance of learning, our work intends to investigate the implicit regularization effects of label noise, under mini-batch sampling settings of stochastic gradient descent (SGD), with the assumption that label noise is unbiased. Specifically, we analyze the learning dynamics of SGD over the quadratic loss with unbiased label noise (ULN), where we model the dynamics of SGD as a stochastic differentiable equation with two diffusion terms (namely a doubly stochastic model). While the first diffusion term is caused by mini-batch sampling over the (label-noiseless) loss gradients, as in many other works on SGD (Zhu et al 2019 ICML 7654–63; Wu et al 2020 Int. Conf. on Machine Learning (PMLR) pp 10367–76), our model investigates the second noise term of SGD dynamics, which is caused by mini-batch sampling over the label noise, as an implicit regularizer. Our theoretical analysis finds such an implicit regularizer would favor some convergence points that could stabilize model outputs against perturbations of parameters (namely inference stability). Though similar phenomenon have been investigated by Blanc et al (2020 Conf. on Learning Theory (PMLR) pp 483–513), our work does not assume SGD as an Ornstein–Uhlenbeck-like process and achieves a more generalizable result with convergence of the approximation proved. To validate our analysis, we design two sets of empirical studies to analyze the implicit regularizer of SGD with unbiased random label noise for deep neural network training and linear regression. Our first experiment studies the noisy self-distillation tricks for deep learning, where student networks are trained using the outputs from well-trained teachers with additive unbiased random label noise. Our experiment shows that the implicit regularizer caused by the label noise tends to select models with improved inference stability. We also carry out experiments on SGD-based linear regression with ULN, where we plot the trajectories of parameters learned in every step and visualize the effects of implicit regularization. The results back up our theoretical findings.
Singly doped colloidal quantum dots as optically addressed nanopositionable qubits
Authors: Barrett Rachel M , Binks David J 
Published: December 2023

Abstract
Colloidal quantum dots (CQDs) are isolated semiconductor nanocrystals with a size-tunable bandgap that can be prepared and processed by well-established solvent-based chemistry, and are currently used for a number of optoelectronic applications. When doped with a single atom, they also have great potential as a platform for optically addressable spin qubits. This perspective first describes the process by which doped CQDs can be made and the electronic structure produced in them by doping with a single atom. The properties that make them particularly well-suited as a spin-photon interface are identified: a local environment for the dopant that is free of unwanted spins; an optical cross-section for the dopant that can be enhanced by orders of magnitude via an exchange interaction with the band edge exciton of the dot; and, as an isolated nanocrystal, the scope for nano-positioning and hence precise incorporation into device structures. Lastly, two areas for development are discussed which would enhance the impact of singly doped quantum dots on quantum technology. The first of these is a synthetic method that ensures deterministic doping with single atoms and the second is to expand the range of dopants available.