bluuebunny/crossref_metadata_2025_split huggingface dataset:
TMP origami jumping mechanism with nonlinear stiffness
Authors: Sadeghi Sahand , Allison Samuel R , Bestill Blake , Li Suyi 
Published: April 2021

Abstract
Via numerical simulation and experimental assessment, this study examines the use of origami folding to develop robotic jumping mechanisms with tailored nonlinear stiffness to improve dynamic performance. We propose a multifunctional structure where the load-carrying skeleton of the structure acts as the energy-storage medium at the same time. Specifically, we use Tachi–Miura polyhedron (TMP) bellow origami—which exhibits a nonlinear ‘strain-softening’ force-displacement curve—as a jumping robotic skeleton with embedded energy storage. TMP’s nonlinear stiffness allows it to store more energy than a linear spring and offers improved jumping height and airtime. Moreover, the nonlinearity can be tailored by directly changing the underlying TMP crease geometry. A critical challenge is to minimize the TMP’s hysteresis and energy loss during its compression stage right before jumping. So we used the plastically annealed lamina emergent origami (PALEO) concept to modify the TMP creases. PALEO increases the folding limit before plastic deformation occurs, thus improving the overall strain energy retention. Jumping experiments confirmed that a nonlinear TMP mechanism achieved roughly 9% improvement in air time and a 13% improvement in jumping height compared to a ‘control’ TMP sample with a relatively linear stiffness. This study’s results validate the advantages of using origami in robotic jumping mechanisms and demonstrate the benefits of utilizing nonlinear spring elements for improving jumping performance. Therefore, they could foster a new family of energetically efficient jumping mechanisms with optimized performance in the future.
Polarized QED cascades
Authors: Seipt Daniel , Ridgers Christopher P , Del Sorbo Dario , Thomas Alec G R 
Published: April 2021

Abstract
By taking the spin and polarization of the electrons, positrons and photons into account in the strong-field QED processes of nonlinear Compton emission and pair production, we find that the growth rate of QED cascades in ultra-intense laser fields can be substantially reduced. While this means that fewer particles are produced, we also found them to be highly polarized. We further find that the high-energy tail of the particle spectra is polarized opposite to that expected from Sokolov–Ternov theory, which cannot be explained by just taking into account spin-asymmetries in the pair production process, but results significantly from ‘spin-straggling’. We employ a kinetic equation approach for the electron, positron and photon distributions, each of them spin/polarization-resolved, with the QED effects of photon emission and pair production modelled by a spin/polarization dependent Boltzmann-type collision operator. For photon-seeded cascades, depending on the photon polarization, we find an excess or a shortage of particle production in the early stages of cascade development, which provides a path towards a controlled experiment. Throughout this paper we focus on rotating electric field configuration, which represent an idealized model and allows for a straightforward interpretation of the observed effects.
On interplay of surface tension and inertial stabilization mechanisms in the stable and unstable interface dynamics with the interfacial mass flux
Authors: Ilyin D V , Goddard W A , Abarzhi I I , Abarzhi S I 
Published: April 2021

Abstract
Non-equilibrium dynamics of interfaces and mixing are omnipresent in fluids, plasmas and materials, in nature and technology, at astrophysical and at molecular scales. This work investigates dynamics of an interface separating fluids of different densities and having interfacial mass flux, and being influenced by the acceleration and the surface tension. We derive solutions for the interface dynamics conserving mass, momentum and energy, find the critical acceleration values separating stable and unstable regimes, and reveal the macroscopic inertial mechanism as primary mechanism of the interface stabilization. We show that while the surface tension influences only the interface, its presence leads to formation of vortical structures in the bulk. For large accelerations the conservative dynamics is unstable, leading to the growth of interface perturbations and the growth of the interface velocity. This new instability can be unambiguously discerned from other instabilities; for strong accelerations it has the fastest growth-rate and the largest stabilizing surface tension value when compared to Landau-Darrieus and Rayleigh-Taylor instabilities. We further find the values of initial perturbation wavelengths at which the conservative dynamics can be stabilized and at which it has the fastest growth. Our results agree with existing observations, identify extensive theory benchmarks for future experiments and simulations, and outline perspectives for application problems in nature and technology.
Nonlinear propagation dynamics of Gaussian beams in fractional Schrödinger equation
Authors: Jiao Ruiyun , Zhang Wenqian , Dou Lichao , Liu Bing , Zhan Kaiyun , Jiao Zhiyong 
Published: April 2021

Abstract
We investigated theoretically the nonlinear propagation dynamics of Gaussian beams in the fractional Schrödinger equation (FSE). When the nonlinearity is introduced into FSE without invoking an external potential, the evolution behaviors of incident Gaussian beams are modulated regularly and some novel phenomena arise. In the one-dimensional case, by changing the values of Kerr or saturated nonlinear coefficient, specific localized or diffracted phenomena appear in the corresponding intensity region, where the splitting angle of one-dimensional incident beam will be modulated flexibly to become larger or smaller in weak nonlinear region, besides, when the self-focusing strength is moderate, the energy of the beam is highly concentrated to form a breathing soliton structure. For two-dimensional case, Kerr or saturated nonlinearity will modulate the energy to the middle or edge in a certain nonlinear region, corresponding to the decrease or increase of the conical diffraction radius, it should be noted that there are two evolution periods under the saturated self-focusing nonlinearity. The work may provide more possibilities for beam modulation in FSE from a nonlinear perspective.
Characterization of optical and radiation shielding behaviors of ferric oxide reinforced bismuth borate glass
Authors: Henaish A M A , Issa Shams A M , Zakaly Hesham M H , Tekin H O , Abouhaswa Aly 
Published: April 2021

Abstract
This study aimed to investigate the ferric oxide effect on optical and radiation shielding behaviors of bismuth borate glasses. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability as a shield or personal protection equipment in industrial and medical fields. The chemical composition (60-x) B2O3 + 20Bi2O3 + 20Li2O+xFe2O3 with different Fe2O3 concentrations were prepared using the melt-quenching technique. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability in industrial and medical fields. The outcomes of optical investigations indicated that direct optical band gap (Eg direct) decrease from 5.11 eV to 4.82 eV, while for indirect transition (Eg indirect) decrease from 4.62 eV to 3.79 eV, with increasing Fe2O3 concentrations. To determine the radiation shielding performance, mass attenuation coefficients (μ
m) of samples were calculated using FLUKA code and XCOM program between 0.015–15 MeV photon energy range. Accordingly, gamma shielding parameters such as mass (MAC) and linear (LAC) attenuation coefficients, half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic numbers (Zeff), electron density (Nel), and fast neutron removal cross sections (ΣR) were evaluated for all glass samples. The results showed that increasing Fe2O3 concentration in glass structure increased the MAC and Zeff. The Fe-10 was reported with the lowest HVL values in addition to the highest MAC and Zeff values.
Study of fuzzy fractional order diffusion problem under the Mittag-Leffler Kernel Law
Authors: Arfan Muhammad , Shah Kamal , Ullah Aman , Abdeljawad Thabet 
Published: April 2021

AbstractOur research work is composed of designing the scheme for computation of some analytical results for fractional order fuzzy diffusion problem under Atangana-Baleanu and Caputo()fractional differential operator. We have obtained the required series type solution by using the Laplace transform along with decomposition techniques. By applying the said method, we have decomposed the required whole quantity into small parts and calculate the series solution for the first few terms We have tested the develop algorithm by three different problems of one, two and three dimensions. The numerical simulations confirm that the solutions of the problems converge to their exact values at the integer-order. Further, we conclude that the fractional-order derivative yields a complete spectrum of fuzzy solutions.
Local primordial non-Gaussianity in the relativistic galaxy bispectrum
Authors: Maartens Roy , Jolicoeur Sheean , Umeh Obinna , De Weerd Eline M. , Clarkson Chris 
Published: April 2021

Abstract
Next-generation galaxy and 21cm intensity mapping surveys will rely on a combination of the power spectrum and bispectrum for high-precision measurements of primordial non-Gaussianity. In turn, these measurements will allow us to distinguish between various models of inflation. However, precision observations require theoretical precision at least at the same level. We extend the theoretical understanding of the galaxy bispectrum by incorporating a consistent general relativistic model of galaxy bias at second order, in the presence of local primordial non-Gaussianity. The influence of primordial non-Gaussianity on the bispectrum extends beyond the galaxy bias and the dark matter density, due to redshift-space effects. The standard redshift-space distortions at first and second order produce a well-known primordial non-Gaussian imprint on the bispectrum. Relativistic corrections to redshift-space distortions
generate new contributions to this primordial non-Gaussian signal, arising from: (1) a coupling of first-order scale-dependent bias with first-order relativistic observational effects, and (2) linearly evolved non-Gaussianity in the second-order velocity and metric potentials which appear in relativistic observational effects.
Our analysis allows for a consistent separation of the
relativistic `contamination' from the primordial signal, in order to avoid biasing the measurements by using an incorrect theoretical model. We show that the bias from using a Newtonian analysis of the squeezed bispectrum could be Δ fNL∼ 5 for a Stage IV Hα survey.
A hybrid simulation of gravitational wave production in first-order phase transitions
Authors: Jinno Ryusuke , Konstandin Thomas , Rubira Henrique 
Published: April 2021

Abstract
The LISA telescope will provide the first opportunity to
probe the scenario of a first-order phase transition happening close
to the electroweak scale. In thermal transitions, the main
contribution to the GW spectrum comes from the sound waves
propagating through the plasma. Current estimates of the GW
spectrum are based on numerical simulations of a scalar field
interacting with the plasma or on analytical approximations — the
so-called sound shell model. In this work we present a novel setup
to calculate the GW spectra from sound waves. We use a hybrid
method that uses a 1d simulation (with spherical symmetry) to evolve
the velocity and enthalpy profiles of a single bubble after
collision and embed it in a 3d realization of multiple bubble
collisions, assuming linear superposition of the velocity and
enthalpy. The main advantage of our method compared to 3d
hydrodynamic simulations is that it does not require to resolve the
scale of bubble wall thickness. This makes our simulations more
economical and the only two relevant physical length scales that
enter are the bubble size and the fluid shell thickness (that are in
turn enclosed by the box size and the grid spacing). The reduced
costs allow for extensive parameter studies and we provide a
parametrization of the final GW spectrum as a function of the wall
velocity and the fluid kinetic energy.
Minimal Theory of Bigravity: construction and cosmology
Authors: De Felice Antonio , Larrouturou François , Mukohyama Shinji , Oliosi Michele 
Published: April 2021

Abstract
Following the path of minimalism in alternative theories of gravity, we construct the “Minimal Theory of Bigravity” (MTBG), a theory of two interacting spin-2 fields that propagates only four local degrees of freedom instead of the usual seven ones and that allows for the same homogeneous and isotropic cosmological solutions as in Hassan-Rosen bigravity (HRBG). Starting from a precursor theory that propagates six local degrees of freedom, we carefully choose additional constraints to eliminate two of them to construct the theory. Investigating the cosmology of MTBG, we find that it accommodates two different branches of homogeneous and isotropic background solutions, equivalent on-shell to the two branches that are present in HRBG. Those branches in MTBG differ however from the HRBG ones at the perturbative level, are both perfectly healthy and do not exhibit strong coupling issues nor ghost instabilities. In the so-called self-accelerating branch, characterized by the presence of an effective cosmological constant, the scalar and vector sectors are the same as in General Relativity (GR). In the so-called normal branch, the scalar sector exhibits non-trivial phenomenology, while its vector sector remains the same as in GR. In both branches, the tensor sector exhibits the usual HRBG features: an effective mass term and oscillations of the gravitons. Therefore MTBG provides a stable nonlinear completion of the cosmology in HRBG.
A search for ultrahigh-energy neutrinos associated with astrophysical sources using the third flight of ANITA
Authors: Deaconu C. , Batten L. , Allison P. , Banerjee O. , Beatty J.J. , Belov K. , Besson D.Z. , Binns W.R. , Bugaev V. , Cao P. , Chen C.H. , Chen P. , Chen Y. , Clem J.M. , Connolly A. , Cremonesi L. , Dailey B. , Dowkontt P.F. , Fox B.D. , Gordon J.W.H. , Gorham P.W. , Hast C. , Hill B. , Hsu S.Y. , Huang J.J. , Hughes K. , Hupe R. , Israel M.H. , Liewer K.M. , Liu T.C. , Ludwig A.B. , Macchiarulo L. , Matsuno S. , McBride K. , Miki C. , Mulrey K. , Nam J. , Naudet C. , Nichol R.J. , Novikov A. , Oberla E. , Prohira S. , Prechelt R. , Rauch B.F. , Ripa J. , Roberts J.M. , Romero-Wolf A. , Rotter B. , Russell J.W. , Saltzberg D. , Seckel D. , Schoorlemmer H. , Shiao J. , Stafford S. , Stockham J. , Stockham M. , Strutt B. , Sutherland M.S. , Varner G.S. , Vieregg A.G. , Wang N. , Wang S.H. , Wissel S.A. 
Published: April 2021

Abstract
The ANtarctic Impulsive Transient Antenna (ANITA) long-duration balloon
experiment is sensitive to interactions of ultrahigh-energy (E>1018 eV)
neutrinos in the Antarctic ice sheet. The third flight of ANITA, lasting 22
days, began in December 2014. We develop a methodology to search for
energetic neutrinos spatially and temporally coincident with potential source
classes in ANITA data. This methodology is applied to several source classes:
the potential IceCube-identified neutrino sources TXS 0506+056 and NGC 1068, flaring high-energy blazars reported by the Fermi All-Sky Variability Analysis, gamma-ray bursts, and supernovae. Among
searches within the five source classes, one candidate was identified as associated
with SN 2015D, although not at a statistically significant level. We proceed to place upper limits on the source classes. We further
comment on potential application of this methodology to more
sensitive future instruments.
Rotational Velocity and Dynamical Mass for the Nuclear Disk of the ULIRG Arp 220
Authors: Azeez Jazeel H. , Zghair Ammar A. , Fadhil Sadeem A. , Zainal Abidin Zamri 
Published: April 2021

Abstract
In this manuscript we use a very high spatial resolution CO (J = 6 - 5) data from Atacama Large Millimeter/Sub-millimeter Array (ALMA) focused to the center region of Arp 220, at distance D = 77.4 Mpc (1 arcsecond = 375 parsec). The CO emission is resolved efficiently by ALMA beam (0.43” x 0.26”). We use long-slit along different direction of our sample to study the kinematic properties of the warm molecular gas within the inner region of Arp 220. We find the observed position - velocity (PV) diagram for this galaxy from its emission line. The major part of the molecular gas in Arp 220 was located mainly in the east and west nucleus. We measure 0.23 × 1010 Mʘ dynamical mass in the central of this galaxy.
Synthesis, and Study the Electrical Properties of Conductive (PVA:PANI)/CuI Blend Composite
Authors: Hassan Ahmed A , Hammed Mohammed G 
Published: April 2021

Abstract
PVA:PANI/CuI thin film composites were prepared by adding (CuI) nanoparticles to the blend of the poly vinyl alcohol and conductive polyaniline with various concentrations (0, 2, 4, 6, and 8% wt) using the casting method technique on glass substrate at room temperature. The type, concentration of charge carriers, and Hall mobility (µH) had estimated from Hall measurement and shown that the polymer thin films before additive of CuI nanoparticles were positive Hall coefficient (P-type). While the polymer thin films for all concentration of CuI nanoparticles have negative Hall coefficient (n-type) except of sample with concentration 6 %wt was remained positive Hall coefficient (P-type). In D.C measurement, increasing of temperature value leads to reduce the electrical resistance, also the D.C conductivity of the thin film composites rises with increasing additive concentration of CuI nanoparticles. The activation energy values for PVA:PANI polymer blend composites decreased when the concentration of CuI nanoparticles increased. Alternating electrical conductivity (σac) increases when the frequency of all samples increases. While the alternating electrical conductivity (σac) remains constant at very low frequency.
Microwave Absorption Properties of PTFE Using T/R Rectangular Waveguide, Nicholson-Rose-Weir, and Finite Element Method
Authors: Yahya Salih Ethar , Khalid Alani Abd-Alrahman , Jawad Mohammed A. , Abbas Zulkifly 
Published: April 2021

Abstract
In this manuscript, the S-parameters, reflection and transmission coefficients, of PTFE at different thicknesses for microwave absorption applications were investigated in conjunction with WR90 T/R rectangular waveguide. Subsequently, the reflection and absorption shielding effectiveness SER
and SEA
values were calculated using the measured S-parameters values, in which an inversely proportional relation was found. Furthermore, using Nicholson-Rose-Weir (NRW) and Finite Element Method (FEM) approaches, the measured S-parameters were validated. Herein, the mean relative errors were calculated; in particular, it was found that the FEM delivers an upright agreement with the measured data in comparison to the utilized NRW. This suggests the usefulness of the FEM approach as a low-cost alternative for the actual laboratory investigation.
The Effect of Plasma Jet on Blood Components of Mice Infected With Diabetes
Authors: Majeed Neean F , Ali Alyaa H , Mazhir Sabah N , Hanon Marwa S 
Published: April 2021

AbstractThe diabetes can be induced by injecting “Alloxan” into animals. it shows a good response in animals specially in “mice, rabbits, mice, dog, and rats”. The drug dosage is between “90 and 200mg/kg of the body weight”. The “Alloxan” motivate “blood glucose” and the experimental animals shows response to the injected drug. The samples which are used in this study are mice male gender with age ranging between three and four months and weight (20-25)gm, these mice are injected with “Alloxan” with a dose of alloxan(200mg/kg) to study effect of alloxan on blood compounds (The cells of white blood, the cells of Red blood and platelets) and study the effect of plasma jet on the infected mice for different time exposure, the component of blood shows different response to the plasma jet effect the White Blood Cells (WBC) and the Platelets(PLT) approach the normal case in the 30 second, the Red Blood Cells (RBC) , HGB the concentration of hemoglobin in whole blood and (HCT) the ratio of red blood cells to the volume of blood plasma approach the normal case in 50 second, the (MCV) mean cell volume approach the normal value in 10 second.
Studying Inelastic Electron Scattering of Magnetic Form Factors M1 for 48Ca Nucleus Using Skyrme Interaction
Authors: Afar Omar Q , Majeed F Z 
Published: April 2021

Abstract
The M1 inelastic scattering form factors from 48Ca nucleus have been investigated through nuclear shell theory. The nuclear effective two body interaction fpbm of Richter has been utilized to generate the two body wave vectors with Harmonic oscillator wave function as a single particle wave function in Fp shell model space. Core polarization effect has been used to include the discarded space (core+ higher configuration) via model space with realistic interaction of Skyrme Sly5 to couple the model space active particles with the pair (particle-hole) excited in energy of 2ћω. Calculated results has been compared to available experimental data.
Annual Average Internal Dose Based on Alpha Emitters in Milk Sample
Authors: Kareem Hashim Abdalsattar , Mezher Hamza A. , Hadi Kadhim Suha , Abid Abojasim Ali 
Published: April 2021

Abstract
Natural radioactivity is common in the environment. As well as in geological formations such as soil, rock, air, water and plants. Which required extensive researches in many countries are due to the global interest in exposure to natural radioactivity. Ten different samples of milk collected from Iraqi markets were evaluated for concentration of alpha radioactivity (uranium concentration, effective radium content and radon concentrations) using CR-39. After exposure, the detectors were etched in a (NaOH) solution of normality (6.25 N) at a temperature of 70 °C for 8 hours. The tracks were calculated by the microscope track-counting system. At a rate of 0.171 ppm, uranium concentrations ranged between 0.079 – 0.263 ppm. While, the effective radium content varied from 53.724 - 178.47 mBq/kg with an arithmetic rate of 116.096 mBq/kg. The variation of the radon exhalation values for the mass unit and for the area unit was also observed between 0.406 - 1.349 mBq/kg.h and 3.076 -10.217 mBq/m
2.h, at a mean rate of 0.943 mBq/kg.h and 6.646 mBq/m2.h, respectively. The average of annual average internal effective dose (AAIED) due to ingestion of 222Rn in milk samples in children and adults has been found 0.60 nSv/y and 0.2 nSv/y respectively, there are excellent correlation between radium concentrations and radon exhalation rate and uranium concentration(R2=1). Thus, the results of this study do not constitute a health hazard to the lives of people because they are within the limits allowed internationally.