bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of direct Urca on the r-mode spin down features of newborn neutron star pulsars
Authors: Routray T R , Pattnaik S P , Gonzalez-Boquera C , Viñas X , Centelles M , Behera B 
Published: January 2021

Abstract
We perform a study on the time duration, final frequency, and exit temperature of the r-mode instability in newborn neutron stars of normal fluid composition under the assumption that the r-mode is the dominating spin-down mechanism. It is found that these spin-down features will vary widely depending on the star mass when direct Urca becomes operative. The occurrence of direct Urca is decided from the stiffness of the symmetry energy of the underlying equation of state, which is still uncertain. The change in the spin-down features in stars of different masses has been studied by computing the magnitude of the bulk viscosity due to the extent of direct Urca coverage in the core. The range for the variation of the symmetry energy stiffness, characterized by the slope parameter L, is decided from the tidal deformability data of the GW170817 event and the maximum mass constraint. The study is done by applying a family of equation of states obtained with the finite range simple effective interaction, constrained at low and intermediate densities by nuclear data and the flow analysis in heavy-ion collisions and at high densities by causality.
Elastic, mechanical, anisotropic, optical and magnetic properties of V2NiSb Heusler alloy
Authors: Güler M , Güler E , Uğur Ş , Uğur G , Charifi Z , Baaziz H 
Published: January 2021

Abstract
We have addressed the several unpublished elastic, mechanical, optical, anisotropic and magnetic properties of V2NiSb inverse Heusler alloy through the density functional theory (DFT) framework. Calculated elastic constants indicate mechanical stability and ductile mechanical character of the alloy. The alloy has high elastic anisotropy. Some optical properties like dielectric function, absorption, reflectance, optical conductivity, etc were also surveyed. According to the obtained results, V2NiSb is a good absorber and high refractive index material in the ultraviolet (UV) region. The magnetic results of the alloy signify typical ferromagnetism with 0.8 μ

B
total magnetic moment and compares well former findings. Our results may further shed light on the possible experimental researches of V2NiSb alloys for practical applications.
Is the atomic metal vapor a dielectric state?
Authors: Khomkin A L , Shumikhin A S 
Published: January 2021

Abstract
We propose a simple method for calculating the metal vapor conductivity at the critical point and near-critical isotherms This method is based on the hypothesis of an electron jellium’s existence as an origin of the conduction band in metal vapor’s gaseous phase. The hypothesis was suggested in our previous works, mentioned further in this article. Satisfactory agreement with the experimental data for alkali metals (Cs, Rb) allows us to conclude that, at the critical point and its vicinity, the atomic metal vapors should be considered as a gaseous metal, that is not a dielectric state of matter.
Development of a perceptually uniform physical scale for visual assessment of specular gloss
Authors: Mohammadalizadeh Ali , Mirjalili Fereshteh , Ameri Farhad , Moradian Siamak , Ansari Keivan , Safi Mahdi 
Published: January 2021

Abstract
Measuring gloss, visually or instrumentally, has been a challenge in many manufacturing and service industries. However, there exists no standardized method for visual evaluation of equidistance specular gloss. This study aimed to design and prepare a psychometric visually equispaced specular gloss scale for the visual measurement of gloss or any other geometric appearance attribute. To this end, a series of lithographically printed black papers, with different levels of gloss from low to high, were prepared to constitute a visually uniform specular gloss scale. Fourteen observers visually quantified the scale in a unidirectional illumination at three different geometries. Analyzing the results shows that the 60° geometry can quantify the equivalent specular gloss efficiently. A uniform specular gloss scale was prepared by assessing the prepared scale visually under the unidirectional illumination at the 60° geometry. Such a visually uniform specular gloss scale could be employed to develop a standard visual evaluation method of specular gloss in all related industries.
Theoretical investigation of a single vapor bubble during Al2O3/H2O nanofluids in power-law fluid affected by a variable surface tension
Authors: Abu-Nab A K , Selima E S , Morad Adel M 
Published: January 2021

Abstract
This article analyzes the growth of the vapor bubble in a novel model of power-law nanofluids (Al2O3/H2O) under a new effect of variable surface tension. The governing equations of the rising vapor bubble flow model are formulated and converted to a single equation describing the bubble dynamics behavior. By employing the model of Plesset and Zwick method, we investigate a new model of equations within power-law nanofluids to examine the effect of different physical parameters such as initial superheating liquid, critical bubble radius, and thermal diffusivity on the vapor bubble formation. Furthermore, the effects of surface tension behavior with the initial bubble radius, time, and initial rate of bubble radius are examined. It is found that the growth of the vapor bubble radius increases with the increase of initial superheating liquid, critical bubble radius, and thermal diffusivity. In addition, the connection between shear stress and shear rate is analyzed in detail. Using appropriate values for the physical parameters, the behavior of solutions of the vapor bubble is discussed. Based on the conducted simulation analysis, the behavior of the solutions is found to be more accurate than those in the previous studies. Besides, the obtained results demonstrate that the vapor bubble in power-law nanofluids grows slower than in pure water.
High-order breather, M-kink lump and semi-rational solutions of potential Kadomtsev–Petviashvili equation
Authors: Cao Yulei , Cheng Yi , He Jingsong , Chen Yiren 
Published: January 2021

Abstract

N-kink soliton and high-order synchronized breather solutions for potential Kadomtsev–Petviashvili equation are derived by means of the Hirota bilinear method, and the limit process of high-order synchronized breathers are shown. Furthermore, M-lump solutions are also presented by taking the long wave limit. Additionally, a family of semi-rational solutions with elastic collision are generated by taking a long-wave limit of only a part of exponential functions, their interaction behaviors are shown by three-dimensional plots and contour plots.
Accurate hemodynamic response estimation by removal of stimulus-evoked superficial response in fNIRS signals
Authors: Galli Alessandra , Brigadoi Sabrina , Giorgi Giada , Sparacino Giovanni , Narduzzi Claudio 
Published: January 2021

Abstract

Objective. We address the problem of hemodynamic response (HR) estimation when task-evoked extra-cerebral components are present in functional near-infrared spectroscopy (fNIRS) signals. These components might bias the HR estimation; therefore, careful and accurate denoising of data is needed. Approach. We propose a dictionary-based algorithm to process each single event-related segment of the acquired signal for both long separation (LS) and short separation (SS) channels. Stimulus-evoked components and physiological noise are modeled by means of two distinct waveform dictionaries. For each segment, after removal of the physiological noise component in each channel, a template is employed to estimate stimulus-evoked responses in both channels. Then, the estimate from the SS channel is employed to correct the evoked superficial response and refine the HR estimate from the LS channel. Main results. Analysis of simulated, semi-simulated and real data shows that, by averaging single-segment estimates over multiple trials in an experiment, reliable results and improved accuracy compared to other methods can be obtained. The average estimation error of the proposed method for the semi-simulated data set is 34% for oxy-hemoglobin (HbO) and 78% for deoxy-hemoglobin (HbR), considering 40 trials. The proposed method outperforms the results of the methods proposed in the literature. While still far from the possibility of single-trial HR estimation, a significant reduction in the number of averaged trials can also be obtained. Significance. This work proves that dedicated dictionaries can be successfully employed to model all different components of fNIRS signals. We demonstrate the effectiveness of a specifically designed algorithm structure in dealing with a complex denoising problem, enhancing the possibilities of fNIRS-based HR analysis.
Two-parameter modified rigid rotor radial equilibrium model for field-reversed configurations
Authors: Ma H.J. , Xie H.S. , Bai Y.K. , Cheng S.K. , Deng B.H. , Tuszewski M. , Li Y. , Zhao H.Y. , Chen B. , Liu J.Y. 
Published: January 2021

Abstract
A new equilibrium pressure profile is proposed that extends the rigid rotor (RR) model with a simple unified expression P = P(ψ; β
s, α, σ) for both inside and outside the separatrix. A new method is described for solving the field-reversed configuration (FRC) one-dimensional (1D) equilibrium with only two parameters. The radial normalized FRC equilibrium profiles for pressure, magnetic field, and current density can be uniquely determined by the dimensionless parameters of

β

s

≡

P

s

/

B

e

2

/
2

μ

0

and δ
s ≡ L
ps/R
s. This modified rigid rotor (MRR) model has sufficient flexibility to accommodate narrow scrape-off layer (SOL) widths and hollow current density profiles, and can be used to fit experimental measurements. A database of 1D plasma equilibria in the (β
s, δ
s) space is provided for the convenience of real-time approximate FRC equilibrium reconstruction. The detailed one-dimensional (1D) characteristics of the equilibrium models are investigated analytically and numerically. The 1D results from the MRR models are also validated using two-dimensional (2D) Grad–Shafranov (G–S) equilibrium solutions.
Towards a maintainable and high efficiency neutral beam system for future fusion reactors
Authors: Simonin A. , Blondel C. , Chaibi W. , Dechelle C. , Drag C. , Villedieu E. 
Published: January 2021

Abstract
Achievement of an economic fusion reactor imposes a high level of unprecedented requirements for neutral beam systems; the first one is the nuclear safety constraints which impose a prerequisite on the ease of access of all injector components to provide a preventive (and curative) maintenance by remote handling while maintaining reactor operation. In addition, the challenge is to develop high-power injectors with very high wall-plug efficiency (above 60%) that are able to operate in stable conditions over several months. There is a significant gap to bridge with respect to the present neutral beam systems, which are characterized by a low efficiency and by complex and long maintenance operations. Evidence that this injector concept does not offer adaptations to cope with the reactor requirements makes it clear that a new concept has to be addressed. An injector concept with modular sources at ground voltage is proposed. The concept makes remote maintenance of the injector components easier, where each source module can be replaced by a new one without breaking the vacuum and affecting injector conditioning. With the grounded and modular ion source, photoneutralization associated with energy recovery appears to be the best route capable of attaining the reactor requirements. This concept of a maintainable neutral beam system would provide a high heating power with a wall-plug efficiency above 70% and unprecedented features such as the capacity of producing temporal and spatial modulation of the beam power for a better control of the plasma stability. Up to now, photoneutralization feasibility studies already carried out on reduced-scale prototypes have not highlighted any showstoppers. Continuation of research and development in the years to come can pave the way towards the achievement of a first full-scale high-power cavity in the 1 MW range, and the realization of a multi-amperes (∼10 A) thin blade-like D− beam.
Quasi-linear theory of forced magnetic reconnection for the transition from the linear to the Rutherford regime
Authors: Huang Wenlong , Zhu Ping 
Published: January 2021

Abstract
Using the in-viscid two-field reduced magneto-hydrodynamic (MHD) model, a new analytical theory is developed to unify the Hahm–Kulsrud–Taylor (HKT) linear solution and the Rutherford quasi-linear regime. Adopting a quasi-linear approach, we obtain a closed system of equations for plasma response in the Taylor problem. An integral form of an analytical solution is obtained for the forced magnetic reconnection, uniformly valid throughout the entire regimes from the HKT linear solution to the Rutherford quasi-linear solution. In particular, the quasi-linear effect can be described by a single coefficient

K

s

∝

S

8
/
5

ψ

c

2

, where

S
=

τ

R

τ

A

and ψ
c are the Lundquist number and amplitude of external magnetic perturbation, respectively. The HKT linear solution for the response can be recovered when the index K
s → 0. On the other hand, the quasi-linear effect plays a key role in the island growth when K
s ∼ 1. Our new analytical solution has also been compared with reduced MHD simulations with agreement.
Divertor power load predictions based on machine learning
Authors: Brenzke M. , Wiesen S. , Bernert M. , Coster D. , Jitsev J. , Liang Y. , von Toussaint U. , ASDEX Upgrade Team  , EUROfusion MST1 Team  
Published: January 2021

Abstract
Machine learning based data-driven approaches to thermal load prediction on the divertor targets of ASDEX upgrade (AUG) are presented. After selecting time averaged data from almost six years of operation of AUG and applying basic physics-motivated cuts to the data we find that we are able to train machine learning models to predict a scalar quantifying the steady state thermal loads on the outer divertor target given scalar operational parameters. With both random forest and neural network based models we manage to achieve decent agreement between the model predictions and the observed values from experiments. Furthermore, we investigate the dependencies of the models and observe that the models manage to extract trends expected from previous physics analyses.
Fermionic quantum cellular automata and generalized matrix-product unitaries
Authors: Piroli Lorenzo , Turzillo Alex , Shukla Sujeet K , Cirac J Ignacio 
Published: January 2021

Abstract
In this paper, we study matrix-product unitary operators (MPUs) for fermionic one-dimensional chains. In stark contrast to the case of 1D qudit systems, we show that (i) fermionic MPUs (fMPUs) do not necessarily feature a strict causal cone and (ii) not all fermionic quantum cellular automata (QCA) can be represented as fMPUs. We then introduce a natural generalization of the latter, obtained by allowing for an additional operator acting on their auxiliary space. We characterize a family of such generalized MPUs that are locality-preserving, and show that, up to appending inert ancillary fermionic degrees of freedom, any representative of this family is a fermionic QCA (fQCA) and vice versa. Finally, we prove an index theorem for generalized MPUs, recovering the recently derived classification of fQCA in one dimension. As a technical tool for our analysis, we also introduce a graded canonical form for fermionic matrix product states, proving its uniqueness up to similarity transformations.
A Review on the Energy prospects of Indian Remote Islands and Preliminary assessment of Marine Current Energy Potential
Authors: Vyshnavi P. , Samad A. , Venkatesan N. , Avital E.J. 
Published: January 2021

Abstract
The islands in the Indian Ocean as other remote islands are often challenged to meet their energy needs, and constantly getting electricity from the mainland is expensive. In this article, the present scenario and future prospects of the energy sources for all the Indian islands are discussed. Data collected from different buoys of INCOIS are analysed, and a location near Minicoy has been chosen for further study. This paper also provides the preliminary analysis of marine current energy feasibility in that location.
Grid integration of Photovoltaic System Interfaced with Artificial Intelligence based Modified Universal Power Quality conditioning system
Authors: Marshall Arockia Dass P , Peer Fathima A 
Published: January 2021

Abstract
Unified Power Quality Compensators (UPQC) in load side utility system is not able to fully suppress harmonies in power grid and distortion in the interface system. To enhance the operation of the UPQC, a Fuzzy based Modified Universal power quality conditioning system (Fuzzy-MUPQCS) is developed. Modified Universal power quality conditioning system (MUPQCS) is a combination of two active filters in series and one active filter in shunt. A 3φ voltage source inverter is also used to maintain a common DC link capacitor voltage through Photo voltaic (PV) system connected to a utility grid. Highest Power Point Tracking (HPPT) algorithm is mainly used to pull out the maximum amount of power in the PV system. In this paper, Proportional integral controller based MUPQCS (PI- MUPQCS) and Fuzzy-MUPQCS are used to analyse the load voltage and load current distortion, THD analysis, power factor measurement, grid voltage and grid current distortion in the three phase system under nonlinear load conditions. The execution of the MUPQCS based 3φ system and the controllers are simulated using Matlab /Simulink model.
Peak Ground Acceleration Analysis using Past Earthquake Data
Authors: Elizabeth Philip Swetha , Helen Santhi M. 
Published: January 2021

Abstract
Peak Ground Acceleration (PGA) is one of the important parameters in the design of seismic resistant structures. In order to predict the value of PGA for a particular place, the past seismic history of that place in terms of data sets is required. The seismic data analysis of regions or nations becomes mandatory due to the frequent occurrence of earthquakes worldwide. This paper presents a study to predict peak ground acceleration of Maharashtra, India by using Excel and MATLAB tools. The available parameters used for the prediction are PGA, epicentral distance, depth and moment magnitude from the year 1912 to 2009. Both the tools have good fit in the prediction of PGA of Maharashtra (R2 >0.9); however Excel may be preferred because of its simplicity and flexibility in handling the data sets.
Comparative Study on the Dynamic Analysis of Blast Loaded Concrete and Steel Structure
Authors: Moniksh Kumar S , Vasugi V , Elavenil S 
Published: January 2021

Abstract
The terrorist attack on buildings or in its surrounding has increased steadily in recent years. Usually, the blast might occur in the ground level thus columns in ground-level undergo impact loading. Since steel and composite type of columns are used nowadays, the nonlinear dynamic analysis of blast loading in such columns has become highly important. This helps to understand the impact of explosions on columns. In this study, RC column, steel and composite column with equal height are designed for the same load-carrying capacity and Finite Element Modeling using ABAQUS. Time History Method is used to analyze the columns. This study aims to simulate and compare the non-linear dynamic analysis of blast loaded concrete and steel structures. The examination of the result exposes the vulnerability in the steel column and the effectiveness of the composite column. RDX of charge weight 100 kg and standoff distance of 1 meter is considered for analysis.
Prediction of self-healing characteristics of GGBS admixed concrete using Artificial Neural Network
Authors: Chaitanya M , Manikandan P , Prem Kumar V , Elavenil S , Vasugi V 
Published: January 2021

Abstract
Concrete has become a significant part of our lives; the utilization of concrete is increasing at a high rate. One of the most constituents of concrete is Ordinary Portland Cement (OPC). The manufacturing process of OPC leads to the emission of huge amounts of CO2. Thus the researchers have started finding alternatives for the replacement of cement. The primary objective of this paper is to investigate the behavior of M40 grade concrete when partially replaced with Ground Granulated Blast Furnace slag (GGBS) at the same time using SAP and study the self-healing behavior of partially replacement concrete. In the self-healing process, the healing agent absorbs the moisture content within the atmosphere to heal the crack. Superabsorbent Polymers (SAPs) are materials that will absorb and retain an oversized volume of water and aqueous solutions. In this investigation, 51 samples of cubes are prepared for compressive strength test and self-healing test, the specimen is pre-cracked on the 28th day for healing purposes. Further, this article aims to predict the self-healing characteristics of the M40 grade of concrete using Neural Networks by incorporating different proportions of GGBS (0%, 40% and 60%) and SAPs. The predicted results obtained from the ANN model were in good agreement with experimental values.
Investigation on performance of water ion modified cement matrix
Authors: Thenua Kanuj , Shanmugasundaram M , Karthiyaini S 
Published: January 2021

Abstract
The water used in preparation of cement composite is going to be altered through magnetization. When the water is kept in magnetic field the additional hardness elements i.e., Ca, Mg and Fe get separated from water. But this separation cannot be done through normal magnetic field. Hence high electromagnetic diffuser or high-end magnets are needed. In this study Neodymium (Nd) - N52 magnets were used which has an atomic number 60. The water kept under the magnetic field for various time periods. The strength variation and development will be studied for mortar on various edges.
Development of Product Assembly Instructional Video for training purpose
Authors: BalaSeshan P , Janardhan Reddy Dr K 
Published: January 2021

Abstract
This work is focused on the development of effective Product Assembly Instructional Videos. Product assembly instructional video is an important element for training, and boost the skills of employees by laying virtual information of any complex assembly. The instructional video is aimed to train employees on “How the product is assembled” with detailed steps to be followed during assembly and with instructional voice-over n a rendered video. It is found from the literature that traditional training often consumes more time and resource for any organization and frequent changes in manpower makes it more difficult for them to spend adequate time to train. So, the instructional videos are helpful to overcome such problems. The method used in this research paper is to develop a framework for product assembly instructional videos. The research s extended via a case study where n these videos are used for training and discuss with the practitioners regarding how they review this model. This paper concludes with a framework for product assembly instructional videos and describing various factors to consider in the creation of industrial training videos. The work also used various software which includes CAD tools, voice recording, impending, and video editing tools to create a training video manual.