bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multipole analysis on stationary massive vector and symmetric tensor fields with irreducible Cartesian tensors
Authors: Wu Bofeng 
Published: June 2023

Abstract
The multipole expansions for massive vector and symmetric tensor fields in the region outside spatially compact stationary sources are obtained by using the symmetric and trace-free formalism in terms of the irreducible Cartesian tensors, and the closed-form expressions for the source multipole moments are provided. The expansions show a Yukawa-like dependence on the massive parameters of the fields, and the integrals of the stationary source multipole moments are all modulated by a common radial factor. For stationary massive vector field, there are two types of ‘magnetic’ multipole moments, among which one is the generalization of that of the magnetostatic field, and another, being an additional set of multipole moments of the stationary massive vector field, can not be transformed away. As to the stationary massive symmetric tensor field, its multipole expansion is presented when the trace of its spatial part is specified, where besides the counterparts of the mass and spin multipole moments of massless symmetric tensor field, three additional sets of multipole moments also appear. The multipole expansions of the tensor field under two typical cases are discussed, where it is shown that if the spatial part of the tensor field is trace-free, the monopole and dipole moments in the corresponding expansion will vanish.
A probabilistic model for the efficiency of cosmic-ray radio arrays
Authors: Lenok Vladimir , Schröder Frank G. 
Published: June 2023

Abstract
Digital radio detection of cosmic-ray air showers has emerged as an alternative technique
in high-energy astroparticle physics. Estimation of the detection efficiency of cosmic-ray radio
arrays is one of the few remaining challenges regarding this technique. To address this problem,
we developed a new approach to model the efficiency based on the explicit probabilistic treatment
of key elements of the radio technique for air showers: the footprint of the radio signal on
ground, the detection of the signal in an individual antenna, and the detection criterion on the
level of the entire array. The model allows for estimation of sky regions of full efficiency and
can be used to compute the aperture of the array, which is essential to measure the absolute flux
of cosmic rays. We also present a semi-analytical method that we apply to the generic model, to
calculate the efficiency and aperture with high accuracy and reasonable calculation time. The
model in this paper is applied to the Tunka-Rex array as example instrument and validated against
Monte Carlo simulations. The validation shows that the model performs well, in particular, in the
prediction of regions with full efficiency. It can thus be applied to other antenna arrays to
facilitate the measurement of absolute cosmic-ray fluxes and to minimize a selection bias in
cosmic-ray studies.
Gauge invariance on the light-cone: curvature perturbations and radiative degrees of freedom
Authors: Fanizza G. , Marozzi G. , Medeiros M. 
Published: June 2023

Abstract
We derive the expressions on the observed light-cone for some relevant cosmological gauge invariant variables, such as the Mukhanov-Sasaki variable and E- and B- modes of the tensor perturbations. Since the structure of the light-cone does not reflect in a direct way the FLRW symmetries, we develop a formalism which is coordinate independent and classifies the perturbations according to their helicities. Even though we work with linear perturbations, our formalism can be readily extended to non-linear theory and put the basis to study the evolution of cosmological perturbations, since the early- until the late-time Universe, directly along the observed light-cone.
Impact of multiple modes on the evolution of self-interacting axion condensate around rotating black holes
Authors: Omiya Hidetoshi , Takahashi Takuya , Tanaka Takahiro , Yoshino Hirotaka 
Published: June 2023

Abstract
Ultra-light particles, such as axions, form a macroscopic condensate around a highly spinning black hole by the superradiant instability. Due to its macroscopic nature, the condensate opens the possibility of detecting the axion through gravitational wave observations. However, the precise evolution of the condensate must be known for the actual detection. For future observation, we numerically study the influence of the self-interaction, especially interaction between different modes, on the evolution of the condensate in detail. First, we focus on the case when condensate starts with the smallest possible angular quantum number. For this case, we perform the non-linear calculation and show that the dissipation induced by the mode interaction is strong enough to saturate the superradiant instability, even if the secondary cloud starts with quantum fluctuations. Our result indicates that explosive phenomena such as bosenova do not occur in this case. We also show that the condensate settles to a quasi-stationary state mainly composed of two modes, one with the smallest angular quantum number for which the superradiant instability occurs and the other with the adjacent higher angular quantum number. We also study the case when the condensate starts with the dominance of the higher angular quantum number. We show that the dissipation process induced by the mode coupling does not occur for small gravitational coupling. Therefore, bosenova might occur in this case.
Primordial black hole formation in Starobinsky's linear potential model
Authors: Pi Shi , Wang Jianing 
Published: June 2023

Abstract
We study the power spectrum of the comoving curvature perturbation ℛ in the
model that glues two linear potentials of different slopes, originally proposed by Starobinsky.
We find that the enhanced power spectrum reaches its maximum at the wavenumber which is π
times the junction scale. The peak is ∼ 2.61 times larger than the ultraviolet plateau. We
also show that its near-peak behavior can be well approximated by a constant-roll model, once we
define the effective ultra-slow-roll e-folding number appropriately by considering the
contribution from non-single-clock phase only. Such an abrupt transition to non-attractor phase
can leave some interesting characteristic features in the energy spectrum of the scalar-induced
gravitational waves, which are detectable in the space-borne interferometers if the primordial
black holes generated at such a high peak are all the dark matter.
Detecting vector charge with extreme mass ratio inspirals onto Kerr black holes
Authors: Zhang Chao , Guo Hong , Gong Yungui , Wang Bin 
Published: June 2023

Abstract
Extreme mass ratio inspirals (EMRIs) are excellent sources for space-based observatories
to explore the properties of black holes and test no-hair theorems. We consider EMRIs with a
charged compact object inspiralling onto a Kerr black hole in quasi-circular orbits. Using the
Teukolsky and generalized Sasaki-Nakamura formalisms for the gravitational and vector
perturbations about a Kerr black hole, we numerically calculate the energy fluxes for both
gravitational and vector perturbations induced by a charged particle moving in equatorial circular
orbits. With one-year observations of EMRIs, we apply the Fisher information matrix method to
estimate the charge uncertainty detected by space-based gravitational wave detectors such as the
Laser Interferometer Space Antenna, TianQin, and Taiji, and we find that it is possible to detect
vector charges as small as q ∼ 0.0049. The results show that EMRIs composed of a Kerr black
hole with a higher spin a and lighter mass M, and a secondary charged object with more vector
charge give smaller relative error on the charge, thus constrain the charge better. The positive
spin of the Kerr black hole can decrease the charge uncertainty by about one or two orders of magnitude.
On the emergence of gravitational dynamics from tensor networks
Authors: Dai Hua-Yu , Sun Jia-Rui , Sun Yuan 
Published: June 2023

Abstract
Tensor networks are used to describe the ground state wavefunction of the quantum many-body system. Recently, it has been shown that a tensor network can generate the anti-de Sitter (AdS) geometry by using the entanglement renormalization approach, which provides a new way to realize bulk reconstruction in the AdS/conformal field theory correspondence. However, whether the dynamical connections can be found between the tensor network and gravity is an important unsolved problem. In this paper, we give a novel proposal to integrate ideas from tensor networks, entanglement entropy, canonical quantization of quantum gravity and the holographic principle and argue that the gravitational dynamics can be generated from a tensor network if the wave function of the latter satisfies the Wheeler–DeWitt equation.
Observation of electron-scale turbulence suppression under weak magnetic shear with neon seeding in EAST plasma
Authors: Chu Y.Q. , Zhang B.S. , Li P. , Yang X.D. , Liu H.Q. , Jie Y.X. , Wu C.B. , Zhang W.M. , Li K.D. , Zhou T.F. , He L. , Zang Q. , Lian H. , Zhong F.B. , Zhu R.J. , Zhang L. F. , Hanada K. 
Published: June 2023

Abstract
Improved confinement caused by Ne injection is investigated in EAST. The safety factor q profile and electron-scale turbulence are studied with a polarimeter-interferometer system and CO2 laser collective scattering system in a series of Ne injection experiments in EAST. Ne with a suitable injection rate can lead to negative magnetic shear in the plasma core, which promotes electron-scale turbulence suppression. The continuous injection of Ne under the reversed shear condition further reduces the electron-scale turbulence intensity. Core electron temperature increase and confinement improvement are observed. QuaLiKiz is applied to model the influence of an impurity and reversed q on turbulence. The combination of stabilization effects of negative magnetic shear and Ne on turbulence is much stronger than the impurity’s own effect, which could explain the experimentally observed electron temperature (T
e) increase and turbulence suppression. Besides, the relationship between pedestal structure induced by Ne injection and lower hybrid wave (LHW)-driven current deposition is discussed. These results provide a new perspective to improve the confinement in the case of Ne injection, i.e. to adjust the Ne injection to modify the ideal plasma equilibrium.
Burr Formation in drilling of aluminum plates under cutting conditions modelled for manual operation
Authors: Miyake Y , Kondo Y 
Published: June 2023

Abstract
Aluminum alloy is widely used in aircraft structural components. The high cutting force in the conventional machining often causes the burr formation in the machined parts. To overcome the problems, machining method with low cutting force are recommended. In this study, we attempted to mechanize the manual drilling (soft-machining) to establish a new drilling method with a small probability of burr generation. The thrust force in manual drilling is less than one-tenth of that in CNC machining. A total of more than 200 holes were drilled with the same drill at 35 to 110N of applied load. In the drilling of single plate, burr formation is related to the inclination of the drill exit surfaces. Even in the drilling of stacked plates, the soft-machining can drill the through holes at the specified points in all conditions. In the soft-machining, the level of load P[N] becomes an important parameter to minimize the damage generation and it may be a mandatory to adjust the load to the minimum level required for cutting and tool feed. Applying soft machining to robotic drilling may solve vibration problem.
Simulation and research on fracture behavior of vehicle structural alloy materials based on XFEM
Authors: Li Peiyuan , Cai Qiaoyan , Wang Fei , Zhang Tao 
Published: June 2023

Abstract
Aluminum alloy 7050 has been widely used in the structure of aerospace vehicles because of its excellent comprehensive performance. In this paper, based on the extended finite element method and classical theory, the material parameters in the finite element simulation are calculated, next the metal plate with a central pre-crack is analyzed for static load breaking and fatigue damage under cyclic loading, the observation of different loading levels and the damage characteristics under different preset crack lengths are summarized, the rules are summarized to provide support for follow-up work.
An algebraic transition model for fluid flows
Authors: Rahman M. M. , Li Baojun , Hasan K. , Chen Sheng 
Published: June 2023

Abstract
An algebraic (zero-equation) transition model is developed to capture multiple transition mechanisms. The newly devised algebraic transition model is parameterized using “flow-structure-adaptive” variables and coupled with the truncated Spalart-Allmaras (SA) turbulence model. The intermittency factor γ relies on “local flow information” and is directly linked to the “vorticity-based production” term of the SA model. Splitting γ into lower and higher regimes of the “free-stream turbulence intensity” enhances the model coefficient calibration and predictions of various phenomena (“natural, bypass, separation-induced, wake-induced”, etc.) encountered in transitional flows. Simulations approve that the new formulation provides good correspondence with other transition models, available in the literature.
Design of a Hydro Bicycle for The Junín- Huancayo Region
Authors: Aylas Quispe A , Tovar J C , Calcina A , Moggiano N 
Published: June 2023

Abstract
The objective of this study was the design of a hydraulic bicycle and the assembly of a floating structure, steering and propulsion to be able to navigate. To this end, a variety of studies have been conducted. A study on the selection of the most suitable materials for the marine environment was also conducted, where a detailed analysis of each component of the power transmission was carried out, where the Shigley-McGrawhill mechanical engineering design book of machine elements was also used. The study of the structural part was carried out to ensure the integrity of the user, also a study of the transmission of pedaling power to the propeller and the pontoons to be able to withstand a maximum load of 120 kg and stability to ensure buoyancy.
Floor vibrations and rectification
Authors: Gad E , Nguyen T , Saidi I , Wilson J , Haritos N 
Published: June 2023

Abstract
Excessive floor vibration due to human excitation is a significant serviceability concern in buildings and other long span structures. The use of lightweight materials, nominal furniture and open plan layouts is resulting in lighter floors with lower damping than traditional older floors and hence an increased risk of excessive vibration response. This paper provides insights into walking excitation, floor response and remedial actions for floors with excessive vibrations.
Toward effective utilization of fly ash and multi-binder system with fly ash in concrete
Authors: Tantermsirikul S , Saengsoy W , Kaewmanee K , Julnipitawong P , Samranwanich T 
Published: June 2023

Abstract
This paper describes first the situation of fly ash in various ASEAN countries. Then the development of fly ash utilization in Thailand is discussed, which includes fly ash specification, standards on durability and service life design for fly ash concrete, and in the final, study results of application potential of various off-spec fly ashes are elaborated. Characteristics of fly ash in different ASEAN countries are different and have different problems. Thailand has 2 major sources of fly ash which have significantly different properties, especially CaO content (high and low CaO). Therefore, the standard specification of the Thai fly ashes classifies the fly ashes based on both quality classes (Classes 1, 2, and 3, with class 1 having the highest quality) and CaO content (high and low CaO). The effects of the fly ash were considered in the durability and service life design standard, for example in estimating the diffusion coefficient of chloride, critical chloride content, carbonation coefficient, and sulfate resistance. Lastly, examples of comparative study results on some off-spec fly ashes (high free lime, dumped wet, and high LOI fly ashes) are demonstrated.
The effect of the corrosion inhibition of steel bar and the property of salt adsorption to salt adsorption type epoxy resin
Authors: Shokyu F , Yamauchi T , Furuta M , Takigawa M , Hirayama G 
Published: June 2023

Abstract
Reinforced concrete structures in a salt-damaged environment are deteriorated by salt damage due to the influence of salt. As a repair measure, repair materials with salt adsorption performance and rebar rust prevention performance are used for inorganic materials. However, products with these added to organic materials are used for various purposes, which are used for various applications as repair materials. Unfortunately, there are few examples of its use becoming possible expected that measures against salt damage will be taken in various applications which have developed a “salt-adsorbing epoxy resin repair material” in which a salt-adsorbing agent is added to epoxy resin, which is an organic material. In addition, this research presented the salt adsorption effect and the corrosion inhibition effect on steel bars applied to each repair application.
Properties and durability of concrete added with recycled polypropylene/polyethylene-based food packaging waste material
Authors: Paglia C , Paderi M 
Published: June 2023

Abstract
The plastic waste from food packaging is hard to be recycled. Different material composition of the polymers makes the mixing impossible. Therefore, the possibility of adding selected Polypropylene / Polyethylene - based materials (PP / PE) in concrete for building applications may be a solution to reduce the waste management. In this study, investigations were carried out on the compressive and flexural strength, the elastic modulus, the density, the workability, the porosity and the water permeability. The durability parameters, such as the freeze/thaw resistance and the accelerated carbonation were also measured on concrete specimens with the addition of recycled PP/PE pellets from food packaging. The results showed that as the addition of plastic material slightly decreased and remained around 4 %, the density, workability, and mechanical properties of the concrete were comparable to the original cementitious material. The porosity was variable, while the water permeability as well as the chloride resistance were not significantly affected by the addition of 4 % plastic aggregates and remained within acceptable values. On the other hand, the freeze/thaw resistance, was significantly lowered in concrete with plastic aggregates in form of granulates.
Different orientations of shear wall in a reinforced concrete structure to control drift and deflection
Authors: Zahid Chowdhury Zubayer Bin , Alam Shahriar , Fahik Azmain , Khan Minhaz Imran , Mohammed Tarek Uddin 
Published: June 2023

Abstract
While Dhaka, the capital city of Bangladesh, adapts to more and more high-rise buildings and skyscrapers, concerns remain about their design efficiency and ability to withstand shear loads from seismic movements. In this study, several orientations and placements of shear walls in a regular G +15 story reinforced concrete building were assessed to observe the nature of the structure subjected to earthquake seismic loads by adopting the Equivalent Static Analysis. CSi ETABS 2019 was utilized to analyze the story shear, drift, displacement, stiffness, torsional irregularity and compared against eight separate models with different shear wall placements. The significance of this study lies in its contribution to the area of designing earthquake-resistant structures with appropriate shear wall locations following the recent Bangladesh National Building Code 2020 (Seismic criteria as per ASCE 7-05). Results reveal that shear walls placed symmetrically and along the shorter span for the selected structural plan have shown less lateral drift and displacement than structures with other shear wall orientations.
Service life optimization and life cycle assessment of concrete using SCMs as partial replacement of cement
Authors: Zahid Chowdhury Zubayer Bin , Rezwan M M , Redwan-Ul-Islam  , Mohammed Tarek Uddin 
Published: June 2023

Abstract
Developing a concrete mixture with the lowest possible environmental impacts while improving durability performance is crucial for a sustainable environment. In this study, a Base Case Scenario (BCS) and Alternative Case Scenario (ACS) concrete mixtures were developed with identical water-to-cement ratio (w/c) of 0.4, having cement substitution of 0% and 34%, respectively. Supplementary cementitious materials (SCMs) such as silica fume, fly ash, and slag cement were implemented as cement replacing mineral admixture. A simplified life-cycle assessment (LCA) was performed to determine environmental impact reduction factors such as fossil fuel depletion, ecotoxicity, ozone depletion, carcinogenic, and global warming. Then a simulation-based approach was carried out to optimize the durability performance of concrete mixtures using Life365™. As a result, a 24.9% reduction of environmental impacts was observed with a decent service life optimization in ACS compared to the BCS mixture.
Internal hydrophobization of cement-based materials by means of silanes
Authors: Materak K , Wieczorek A , Bednarska D , Koniorczyk M 
Published: June 2023

Abstract
The paper shows the opportunity of application of an organosilicon compound such as triethoxyoctylsilane (OTES) containing long, hydrophobic alkyl sidechains (octyl groups – C8H17) attached to the silicon atoms, as the admixtures for internal hydrophobization of cementitious building materials characterized by a porous internal structure. The study included the cement paste, mortar and concrete with three different hydrophobic admixtures based on triethoxyoctylsilane, but with miscellaneous concentration of the triethoxyoctylsilane in the admixture and different dosage in the fresh mix. The impact of organosilicon hydrophobic admixtures on the mechanical properties such as compressive strength, capillary water absorption of the cement mortar and concrete and the microstructure of cement paste was investigated. The hydrophobic, silicon-based admixtures decrease the capillary water absorption coefficient significantly. Even by 81.1% in case of cement mortar. The mechanical strength of cement mortar is also decreased, by 23.6%. The noticeable changes in the internal structure of pores of cement paste only for one admixture is observed.
Data-driven ultimate condition prediction of UHPC columns subjected lateral confinement using Artificial Neural Network (ANN) approach
Authors: Lee Stein S Y , Hiew Shack Yee , Raman Sudharshan N 
Published: June 2023

Abstract
Despite the superior mechanical properties of Ultra-High Performance Concrete (UHPC) in comparison to conventional concrete, UHPC is still not widely used in the construction industry due to the lack of design standards. This research mainly focuses on using advanced computational tools for the prediction of ultimate stress and its corresponding strain for confined UHPC columns, to facilitate the process of analysis and design, and to support further development of standards. Characteristic parameters of confined UHPC column samples were extracted from available literature as the input, and the corresponding ultimate stress and strain as the output. Artificial Neural Network (ANN) technique was adopted to process the input parameters in order to train and predict the output. In the regression analysis, the trained networks exhibited the coefficients of determination (R2) of 0.995 and 0.964 for the prediction of ultimate stress and corresponding strain respectively. The weights and biases within the best performance ANN from the k-fold cross validation can be extracted to perform mathematical solutions for the prediction in design.