bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparing the economics welfare on leading rice exports countries based on copula SEM: the case of India, Thailand, and Vietnam
Authors: Nunti Chonrada , Yamaka Woraphon , Boonyakunakorn Petchaluck 
Published: September 2020

Abstract
This paper aims to investigate economics welfare gain from main rice export countries, namely India, Thailand, and Vietnam, by measuring the demand and supply of exporters and importers estimated by the copula-based Simultaneous ECM Approach. This model exploits a benefit of copula functions which allow the error’s distribution of both demand and supply equations to have more realistic distributions. The highlighted empirical results show the adjustment of importing countries to the equilibrium. Thai rice export market can adjust better than the other two countries. This means that the export market is very strong. In the supply side, India is the fastest country in adjusting to its equilibrium. For the economic welfare aspect, the most welfare benefits in Thai rice trade belong to importing countries. Whereas, the most welfare benefits in India rice trade belong to exporting countries.
Joint mean-correlation model and its application to NorStOP binary data
Authors: Peng Cheng , Yang Yihe , Zhou Jie , Pan Jianxin 
Published: September 2020

AbstractIn this paper we propose a generalized estimating equations method to joint model the mean and correlation structures for longitudinal binary data based on Gaussian copula, and apply it to a large cohort study for the UK’s North Staffordshire Osteoarthritis Project (NorStOP), where the responses can be pre-processed to binary variables. The resulting estimators for the mean and correlation parameters are proven to be consistent and asymptotically normally distributed. Since the theory and simulation results were studied in our previous manuscript [1], we give a brief introduction of our approach but mainly focus on its application to the NorStOP data.
Hawgent dynamic mathematic software as mathematics learning media for teaching quadratic functions
Authors: Tanu Wijaya Tommy , Ying Zhou , Chotimah Siti , Bernard Martin , Zulfah  , Astuti  
Published: September 2020

AbstractAccording to the observation of schools in Indonesia, the quadratic function graph is a lesson for junior high school students. For it is an abstract concept, students have difficulties to understand and picture out the graph functions. The main purpose of this research is to design a learning media to improve students’ learning achievement by using hawgent dynamic mathematic software. The method of this research is research and development method. The target audience of this research were 32 students in experimental class and 32 students in controlled class. The result of this research is the material expert, research and media experts obtaining “valid” criteria. This means that the software is better than traditional teaching methods as students are able to easily visualise and generalise the graphical form of the quadratic equation. This automatically increases student’s learning achievement and makes them find math interesting.
Research on the results of the advanced mathematics teaching of college students of science: the effect of STC teaching mode based on “Internet +”
Authors: Zheng Zhibo , Zhao Wenyan , Liu Guoqi , Du Yanan , Sun Jiangjie 
Published: September 2020

Abstract
We uses markov evaluation model to evaluate the effectiveness of STC teaching (STC teaching mode is a method of combining online services and offline services mode of “Self-directed learning-Traditional teaching-Collaborative learning”). In the 2018-2019 academic year, Control class group (traditional teaching mode) and experimental class group (STC teaching mode) will be taught for the Advanced Mathematics Teaching of college students of science. We use the score data of the two classes as the evaluation basis. The results show that the STC teaching effect is significant.
Some classes of permutation polynomials with the form (xk
+ x)
s
+ x
2
n
−2
Authors: Yi Shaojun , Zhu Xishun , Wu Jianhua 
Published: September 2020

Abstract
For a prime 2, let n be a positive integer, and F
2
n

be the finite field with 2
n
elements. In this paper, we propose several classes of permutation polynomials with the form (xk
+ x)
s
+ x
2
n
−2 over finite fields F
2
n

which have the highest degree of algebra.
New Farkas-type inequalities of mixed interval systems for AE solvability
Authors: Xia Mengxue , Li Haohao 
Published: September 2020

Abstract
Interval Farkas type inequality is an important tool to prove the optimality condition of interval optimization model. This research gives a Farkas-type inequality for AE solvability of a specific mixed interval linear system including both equality and inequality by using logical quantifiers. Some Farkas-type inequalities for different solvability established in previous literatures are special cases of the main result of this paper.
Research on credit line of supply chain enterprises based on data sharing
Authors: Liu Yue , Hu Jiajing 
Published: September 2020

Abstract
Based on the deficiencies of the existing research on the credit line of supply chain enterprises, this paper taking data sharing as research perspective, established the credit model of supply chain enterprises using data sharing. Through the case study of L Corporation Group, it is found that: 1) the supply chain can integrate information advantages, increase credit line and reduce financing costs; 2) the credit line of supply chain enterprises raises with the increase of data sharing degree; 3) the existing credit models of the banks are conservative, the actual credit line of enterprises is insufficient. The credit model constructed in the paper fully considers the effects of data sharing of related transactions between enterprises on the credit line in the context of supply chain, which can provide ideas for realizing the win-win situation of maximizing the financing scale of supply chain enterprises and minimizing the risk of banks.
A potentially stable and potentially nilpotent tree sign pattern that is not spectrally arbitrary
Authors: Yu Berlin 
Published: September 2020

Abstract
It has been shown that a 4 x 4 tree sign pattern is spectrally arbitrary if and only if it is potentially stable and potentially nilpotent in [M. Arav, F. Hall, Z. Li, K. Kaphle, N. Manzagol, spectrally arbitrary tree sign patterns of order 4, Electron. J. Linear Algebra, 20 (2010), 180-197], where the authors asked whether the above important theorem can be extended to the 5 x 5 case. In this paper, we negatively answer this question by constructing a 5x5 potentially stable and potentially nilpotent tree sign pattern which is shown to be not spectrally arbitrary.
Rumor spreading model considering the influence of public opinion environment
Authors: Pan Qiuhui , Liu Yiling , Lu Siying , He Mingfeng 
Published: September 2020

Abstract
Rumor spreading has a profound influence on daily lives. There are several factors influencing rumor spreading. In this paper, we assume that there are two kinds of individuals in the crowd: those who do not know the rumors and those who learn about the rumors. And in the latter category, there are two attitudes toward rumors: those who are convinced of rumors and those who hold an objective attitude. Those convinced and objective individuals form a public opinion environmental factor conducive to the spread of rumors. Based on the public opinion environmental influence whose intensity decays with time, a model with two attitudes toward rumors is established. With numerical simulations, we illustrated the conversion state of three categories because of public opinion environmental factors, analyzing the sensitivity of the model. The results showed that it is beneficial to control the rumor propagation when controlling the influence of those who are convinced of rumors and those who hold an objective attitude rather than constraining one of them individually. And it was commonsensical that increasing the attenuation intensity of the two attitude rumors was also an effective way conducive to the control.
Inverse Sturm-Liouville problem on three-star graph with a discontinuity
Authors: Lv Kang 
Published: September 2020

Abstract
This paper deals with the inverse Sturm-Liouville problem with one discontinuous point on the three-star graph, suppose the potential is known on all edges except one, the one which has discontinuous point, we deduce the distribution of the eigenvalues, and prove that one spectrum uniquely determines a part of jump information. And by the reasonable assumption, we prove that if all the eigenvalues are simple, then one spectrum uniquely determines the unknown potential, too.
A new solution of thin elastic rod by dynamic analogy
Authors: Zhang Shuai , Zhang Yitong , Wang Peng 
Published: September 2020

Abstract
Inspired by Kirchhoff dynamic analogy, we write the Kirchhoff equation of thin elastic rod in form of curvature expression. Compared it with nonlinear Schrödinger equation, we extend a Jacobi elliptic function analogy solution to elastic rod equation and give a new alternative way to solve the Kirchhoff equation.
Improved Menter’s one-equation turbulence model
Authors: Rahman Md Mizanur , Zhang Yang , Zhu Zefei 
Published: September 2020

Abstract
Compatible modifications to original Menter model (OMM) are incorporated using an elliptic relaxation approach to accurately accounting non-local characteristics accompanied by near-wall turbulence. Coefficients/functions of improved Menter model (IMM) are parameterized with the elliptic relaxation function to imitate the combined effects of near-wall turbulence and non-equilibrium. The characteristic length scale involved in the elliptic relaxation scheme is constructed in terms of viscous and turbulent length scales in conjunction with a non-singular strain-rate invariant. Non-local effects are consequently reinforced by the mean flow and turbulent variables. A non-linear eddy-viscosity damping function is invoked to relax the viscous length-scale coefficient pertaining to the elliptic relaxation model. Comparisons indicate that the IMM substantially improves the accuracy of flow simulations compared to the OMM and widely used Spalart-Allmaras (SA) model. A good consensus is obtained between IMM and DNS (direct numerical simulation)/measured data.
Magnetoencephalogram analysis of depression based on multivariable sign transfer entropy
Authors: Zhang Yu , Zhang Yiling , Chen Junwei , Yan Wei , Chen Zihan , Wang Jun 
Published: September 2020

Abstract
In this paper, multivariable sign transfer entropy algorithm is used to calculate the multivariable sign transfer entropy values of the same brain region and different brain regions stimulated by different emotional images in patients with depression and healthy control group. The connectivity of the magnetic channels in the brain region and between brain regions is studied. And the conclusions of negative cognitive bias in depressed patients [1] and functional asymmetry of emotion of cerebral hemispheres are verified [2]. The results showed that: For different brain regions, the left occipital region →frontal region under positive emotional picture stimulation and neutral emotional picture stimulation can significantly distinguish the depressed patients’ group from the healthy control group, the corresponding connection strength of depressed patients was significantly weaker than that of healthy control group.
Retailer’s optimal procurement plan considering random demand, delayed payment and cash discount
Authors: Huang Ruiqi , Huang Yongbiao , Lu Yueli 
Published: September 2020

AbstractMany inventory models have been established based on determined demand but ignore the fact that demand can be affected by random factors. A procurement model considering random demand, different trade credit and cash discount is established in this paper. Due to the randomness of demand, possibilities of salvage or stock out at the end of the cycle are considered, and these cases can be dealt as classic news vendor problem. The optimal procurement strategy for the expected profit is derived by some theoretical results in this paper, which are also illustrated by a series of numerical examples and the corresponding sensitivity analyses are also presented.
Influence of order enhancement of the Runge-Kutta method on low-order turbulence statistics of incompressible wall turbulence under a second-order central difference scheme
Authors: Jomura Shotaro , Suzuki Hiroki , Hasegawa Yutaka , Matsuo Shinnosuke , Mochizuki Shinsuke 
Published: September 2020

Abstract
In this study, we attempt to understand the effects of the accuracy order of higher-order Runge-Kutta methods on the turbulence statistics of incompressible wall turbulence. A second-order central difference scheme is used to spatially discretize the governing equations, considering the widely used lower-order spatial discretization. The effects of the difference in the order of the Runge-Kutta scheme are investigated using a turbulent channel flow. The turbulence statistics obtained are compared with those reported in three previous studies. Based on our results, we infer that the rms values of the mean velocity, mean pressure, Reynolds stress, and velocity fluctuation of the turbulent channel flow are not affected by the difference in the accuracy order of the higher-order Runge-Kutta method. The fluctuation of the rms values of static pressure obtained by using the fourth-order Runge-Kutta method were consistent with those obtained in previous studies.
Introduction
Authors: Assmann Ralph , Ferrario Massimo 
Published: September 2020

4th European Advanced Accelerators Concepts.
More than 250 scientists from all over the world gathered from Sep 15 – 21 at the 4th European Advanced Accelerator Concept Workshop (EAAC) on the Island of Elba in Italy. Specialists from accelerator physics, RF technology, plasma physics, instrumentation and the laser field discussed ideas and directions towards a new generation of ultra compact and cost effective accelerators with ground-breaking applications in science, medicine and industry.
The EAAC was founded by the European Network for Novel Accelerators (EuroNNAc) in 2013 and has grown in its fourth edition into a meeting with world-wide visibility, rapidly catching up with the long tradition of the Advanced Accelerator Concepts workshop (AAC) in the US. At the EAAC senior scientists from various specialties mix with junior experts and a large community of young students, attracted by the promise and success of compact particle accelerators. In 2019 about 50 PhD students presented their work at the EAAC. Besides the reports on scientific achievements the large diversity in gender, age distribution and nationalities made the EAAC 2019 a special event and a great success for the accelerator field.
Group photo of the EAAC 2019 attendants is present in this pdf.

Committees

List of Workshop Organizing Committee, Programme Committee, International Advisory Committee, Local Organizing Committee and Proceedings Editors are available in this pdf.
Summary of European Advanced Accelerator Workshop (EAAC) Working Group 1: Electron Beams from Plasma
Authors: Corde Sebastien , Irman Arie , Turner Marlene 
Published: September 2020

Abstract
We summarize oral contributions presented in Working Group (WG) 1 of the European Advanced Accelerator Workshop (EAAC). Working Group 1 is titled ’Electron Beams from Plasma’ and included presentations and discussions on the following subjects: laser- and beam-driven plasma wakefield acceleration, recent experimental results and planned experiments, single and multi drive laser pulses (or particle bunches), external and self-injection techniques, staging as well as advanced beam control and manipulation.
Towards experimental investigation of hosing instability mitigation at the PITZ facility
Authors: Loisch G , Gross M , Koschitzki C , Lishilin O , Ossa A Martinez de la , Osterhoff J , Stephan F 
Published: September 2020

Abstract
Beam-driven plasma wakefield acceleration (PWFA) allows for high gradient acceleration of electron beams and hence is a promising candidate for compact and cost-efficient drivers of applications demanding high brightness beams. One of the main challenges in these accelerators is to control beam-plasma instabilities with rapid growth rates which are induced by the strong transverse components of the wakefields. The hosing instability, a growing transverse oscillation of the beam centroid caused by coherent coupling between bunch slice centroids and transverse wakefields, was predicted to set severe limits on the possible acceleration distance in PWFAs. Several methods have been proposed to damp or even suppress the hosing of the beam, prevent beam-breakup and thus allow stable operation. Here, we present preparations and simulation studies aiming at the experimental investigation of hosing suppression mechanisms at the PITZ facility.
Determination of the Charge per Micro-Bunch of a Self-Modulated Proton Bunch using a Streak Camera
Authors: Bachmann A.-M. , Muggli P. 
Published: September 2020

Abstract
The Advanced Wakefield Experiment (AWAKE) develops the first plasma wakefield accelerator with a high-energy proton bunch as driver. The 400 GeV bunch from CERN Super Proton Synchrotron (SPS) propagates through a 10 m long rubidium plasma, ionized by a 4TW laser pulse co-propagating with the proton bunch. The relativistic ionization front seeds a self-modulation process. The seeded self-modulation transforms the bunch into a train of micro-bunches resonantly driving wakefields. We measure the density modulation of the bunch, in time, with a streak camera with picosecond resolution. The observed effect corresponds to alternating focusing and defocusing fields. We present a procedure recovering the charge of the bunch from the experimental streak camera images containing the charge density. These studies are important to determine the charge per micro-bunch along the modulated proton bunch and to understand the wakefields driven by the modulated bunch.
New Tunable High Gradient Permanent Magnet Quadrupole for Plasma Wake Field Acceleration at SPARC _LAB
Authors: Vannozzi A , Alesini D , Sanelli C , Vaccarezza C 
Published: September 2020

Abstract
Applications such as colliders and plasma wake field acceleration require high gradient quadrupoles, in the range of 400-500 T/m and with a bore of few millimeters in diameter.
The design of a tunable high gradient permanent magnet quadrupole (PMQ), based on the QUAPEVA design [1] developed for the SOLEIL synchrotron, is presented. The quadrupole has a fixed part made of a Halbach quadrupole array [3, 4] surrounded by four permanent magnet cylinders with a radial orientation of the magnetic momentum. The gradient is regulated by rotating the cylinders, reaching a tunability greater than the 25%.
The quadrupole has been designed for the COMB plasma wake field beam driven experiment for the SPARC_LAB test-facility at INFN-LNF [2], one of the candidates to host the EuPRAXIA project [7, 8]. The present layout foresees two triplets where the focusing strength tuning is performed by moving two quadrupoles of each triplet along the beam axis. The new quadrupoles have bigger gradient and less multipolar content than actual ones, moreover it has a tuning system that does not need any shift of the magnet.
Design considerations for permanent magnetic quadrupole triplet for matching into laser driven wake field acceleration experiment at SINBAD
Authors: Yamin S , Assmann R W , Dorda U , Lemery F , Marchetti B , Panofski E , Walker P A 
Published: September 2020

Abstract
The ARES (Accelerator Research experiment at SINBAD) Linac at SINBAD (Short and INnovative Bunches and Accelerators at DESY) facility at DESY aims to produce high brightness ultrashort electron bunches (sub fs to few fs) at around 100 MeV, suitable for injection into novel accelerators e.g. dielectric Laser acceleration (DLA) and Laser Driven Wakefield acceleration (LWFA). The external injection experiment planned at ARES aims for stable LWFA by combining the reproducible conventional RF-based accelerator technology, with high-power plasma wakefield dynamics. The LWFA experiment demands Twiss parameter β to be of the order of few mm, in order to avoid emittance growth because of high accelerating gradient in the plasma. The ARES Linac is capable of producing ultra-short bunches at around 100-150 MeV, so the effect of space charge is significantly high. To match such a space charge dominated beam, strong transverse focusing is required. A Permanent Magnetic Quadrupole (PMQ) triplet is one promising focusing strategy. In this paper, we report the technical design constraints and findings for stable settings for PMQ triplet to match the requirements of the electron beam properties and study of phase spaces for final focus into LWFA experiment.
Stability of elliptical self-modulating long proton bunches in plasma wakefields
Authors: Perera A , Muggli P , Welsch C P 
Published: September 2020

Abstract
The AWAKE experiment at CERN recently demonstrated the world’s first acceleration of electrons in a proton-driven plasma wakefield accelerator. Such accelerators show great promise for a new generation of linear e-p colliders using 1-10 GV/m accelerating fields. Efficiently driving a wakefield requires 100-fold self-modulation of the 12cm Super Proton Synchrotron (SPS) proton bunch using a plasma-driven process which must be carefully controlled to saturation. Previous works have modelled this process assuming azimuthal symmetry of the transverse spatial and momentum profiles. In this work, 3D particle-in-cell (PIC) simulations with the code QuickPIC are used to model the self-modulation of non-round bunches. We find that asymmetry in the initial seed wakefield leads to the formation of highly asymmetric microbunches which evolve incoherently along the symmetry axes of the initial bunch profile. However, the resonantly-driven accelerating wakefield is highly stable to both focused and astigmatic non-round bunches.
Simulation of Polarized Beams from Laser-Plasma Accelerators
Authors: Hützen Anna , Thomas Johannes , Lehrach Andreas , Rakitzis T.Peter , Pukhov Alexander , Ji Liangliang , Wu Yitong , Engels Ralf , Büscher Markus 
Published: September 2020

Abstract
The generation of polarized particle beams still relies on conventional particle accelerators, which are typically very large in scale and budget. Concepts based on laser-driven wakefield acceleration have strongly been promoted during the last decades. Despite many advances in the understanding of fundamental physical phenomena, one largely unexplored issue is how the particle spins are influenced by the huge magnetic fields of plasma and, thus, how highly polarized beams can be produced. The realization of laser-plasma based accelerators for polarized beams is now being pursued as a joint effort of groups from Forschungszentrum Jülich (Germany), University of Crete (Greece), and SIOM Shanghai (China) within the ATHENA consortium. As a first step, we have theoretically investigated and identified the mechanisms that influence the beam polarization in laser-plasma accelerators. We then carried out a set of Particle-in-cell simulations on the acceleration of electrons and proton beams from gaseous and foil targets. We could show that intense polarized beams may be produced if pre-polarized gas targets of high density are employed. In these proceedings we further present that the polarization of protons in HT and HCl gas targets is largely conserved during laser wake-field acceleration, even if the proton energies enter the multi-GeV regime. Such polarized sources for electrons, protons, deuterons and 3He ions are now being built in Jülich. Proof-of-principle measurements at the (multi-)petawatt laser facilities PHELIX (GSI Darmstadt) and SULF (Shanghai) are in preparation.