Magnetic Nonreciprocity in a Hybrid Device of Asymmetric Artificial Spin-Ice-Superconductors

Controlling the size and distribution of potential barriers within a medium of interacting particles can unveil unique collective behaviors and innovative functionalities.We introduce a unique superconducting hybrid device using a novel artificial spin ice structure composed of asymmetric nanomagnets.This structure forms a distinctive superconducting pinning potential that steers unconventional motion of superconducting vortices,thereby inducing a magnetic nonreciprocal effect,in contrast to the electric nonreciprocal effect commonly observed in superconducting diodes.Furthermore,the polarity of the magnetic nonreciprocity is in situ reversible through the tunable magnetic patterns of artificial spin ice.Our findings demonstrate that artificial spin ice not only precisely modulates superconducting characteristics but also opens the door to novel functionalities,offering a groundbreaking paradigm for superconducting electronics.

An analogical study of wave equations,physical quantities,conservation and reciprocity equations between electromagnetic and elastic waves

This paper presents an analogical study between electromagnetic and elastic wave fields,with a one-to-one correspondence principle established regarding the basic wave equations,the physical quantities and the differential operations.Using the electromagnetic-to-elastic substitution,the analogous relations of the conservation laws of energy and momentum are investigated between these two physical fields.Moreover,the energy-based and momentum-based reciprocity theorems for an elastic wave are also derived in the time-harmonic state,which describe the interaction between two elastic wave systems from the perspectives of energy and momentum,respectively.The theoretical results obtained in this analysis can not only improve our understanding of the similarities of these two linear systems,but also find potential applications in relevant fields such as medical imaging,non-destructive evaluation,acoustic microscopy,seismology and exploratory geophysics.

Impact of BRICS Trade Facilitation on China's Exports Using Cross-Border E-Commerce

With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important force in the global economy, and the progress of the BRICS countries' trade facilitation level has an important impact on the global trade environment. This paper conducts an in-depth study of the dynamic changes in BRICS trade facilitation from 2013 to 2022, and uses an extended gravity model to analyze the specific impact of this change on China's exports using cross-border e-commerce. The results show that although the BRICS countries have made some progress in trade facilitation, the overall level still needs to be improved, and there are obvious differences among member countries. However, the improvement of trade facilitation among BRICS countries has undoubtedly brought significant positive effects to China's exports using cross-border e-commerce.

Iran-Turkmenistan Relations:Cross-Border Ethnic Groups and Comprehensive Governance Strategies

This study delves into the bilateral relations between Iran and Turkmenistan,focusing on the multidimensional impacts of cross-border ethnic groups,cultural diplomacy,and energy cooperation.The research reveals that despite challenges in security cooperation,such as regional political ideological differences and uneven power distribution,Iran has adopted diverse strategies to enhance cultural identity,social cohesion,and promote economic cooperation.Iran actively seeks to repair relations with Turkmenistan by emphasizing shared historical and cultural backgrounds,particularly the presence of cross-border Turkmen ethnic groups.Specific measures include developing cultural tourism,organizing cultural weeks,and establishing commemorative days.In the economic sphere,the two countries have signed significant natural gas supply agreements,strengthening energy cooperation.Iranian leaders often emphasize“blood ties”and deep cultural connections in diplomatic statements,combining cultural diplomacy with practical economic cooperation.The study’s findings indicate that Iran’s initiatives have led to the reorganization of national space and social reconstruction in border regions,promoting changes in public policy.By integrating cultural identity,historical connections,and economic interests,Iran has adopted a sophisticated diplomatic approach,laying the foundation for more stable and enduring bilateral relations while contributing to regional stability and sustainable development.

Reciprocity Relation between Alternative Gravity Formulas

We compare Newton’s force law of universal gravitation with a corrected simple approach based on Bhandari’s recently presented work, where the gravitation constant G is maintained. A reciprocity relation exists between both alternative gravity formulas with respect to the distances between mass centers. We conclude a one-to-one mapping of the two gravitational formulas. We don’t need Einstein’s construct of spacetime bending by matter.

Micro,Small,and Medium Enterprises’Cross-Border Business Strategies

This paper explores the operational strategies of cross-border micro, small, and medium enterprises (MSMEs). Against the backdrop of globalization and digitalization, cross-border trade has become one of the important pathways for many MSMEs to achieve growth and competitive advantage. Firstly, the paper outlines the concept and characteristics of cross-border MSMEs, as well as the analysis of their operational environment in the context of globalization, including political, economic, social, technological, environmental, and legal factors. Secondly, the paper proposes operational strategies for cross-border MSMEs, including international market selection and positioning, cross-border marketing strategies, supply chain management, cross-border financial management, and cross-border risk management. Finally, the paper summarizes the importance of effectively implementing these strategies for cross-border MSMEs to seize international market opportunities, reduce operational risks, and enhance competitiveness and profitability.

Uniqueness,reciprocity theorem,and plane waves in thermoelastic diffusion with a fractional order derivative

In this work, a theory of thermoelasticity with diffusion is taken into consideration by using the methodology of fractional calculus. The governing equations for particle motion in a homogeneous anisotropic fractional order generalized thermoelastic diffusive medium are presented. Uniqueness and reciprocity theorems are proved. The plane wave propagation in the homogeneous transversely isotropic thermoelastic diffusive medium with fractional order derivative is studied. For the two-dimensional problem, there exist a quasi-longitudinal wave, a quasi-transverse wave, a quasi-mass diffusion wave, and a quasi-thermal wave. From the obtained results, the different characteristics of waves, like phase velocity, attenuation coefficient, specific loss, and penetration depth, are computed numerically and presented graphically. Some special cases are also discussed.

Solution of scattering from rough surface with a 2D target above it by a hybrid method based on the reciprocity theorem and the forward-backward method

This paper proposes a hybrid method based on the forward-backward method （FBM） and the reciprocity theorem （RT） for evaluating the scattering field from dielectric rough surface with a 2D target above it. Here, the equivalent electric/magnetic current densities on the rough surface as well as the scattering field from it are numerically calculated by FBM, and the scattered field from the isolated target is obtained utilizing the method of moments （MOM）. Meanwhile, the rescattered coupling interactions between the target and the surface are evaluated employing the combination of FBM and RT. Our hybrid method is first validated by available MOM results. Then, the functional dependences of bistatic and monostatic scattering from the target above rough surface upon the target altitude, incident and scattering angles are numerically simulated and discussed. This study presents a numerical description for the scattering mechanism associated with rescattered coupling interactions between a target and an underlying randomly rough surface.

DUAL RECIPROCITY HYBRID BOUNDARY NODE METHOD FOR THREE-DIMENSIONAL ELASTICITY WITH BODY FORCE

Combining Dual Reciprocity Method （DRM） with Hybrid Boundary Node Method （HBNM）, the Dual Reciprocity Hybrid Boundary Node Method （DRHBNM） is developed for three-dimensional linear elasticity problems with body force. This method can be used to solve the elasticity problems with body force without domain integral, which is inevitable by HBNM. To demonstrate the versatility and the fast convergence of this method, some numerical examples of 3-D elasticity problems with body forces are examined. The computational results show that the present method is effective and can be widely applied in solving practical engineering problems.

Generation method of GPS L1C codes based on quadratic reciprocity law

A new code concept is used for the L1 civil（L1C） signal of the global positioning system（GPS）.The generation of L1C codes is quite different from the generation of traditional ranging codes.Thus,it is necessary to find a method for the correct generation to pave the way for future research.L1C codes are based on only one Legendre sequence which consists of Legendre symbols.To calculate these Legendre symbols,the Euler criterion is always used to evaluate quadratic residues.However,due to the great length of L1C codes,this procedure causes overflow problems.Therefore,the quadratic reciprocity law,some related theorems and properties are introduced to solve the problems.Moreover,if the quadratic reciprocity law,some related theorems and properties are used to calculate different Legendre symbols,the combination modes may vary,which causes a complex generation process.The proposed generation method deals with this complex generation process effectively.In addition,through simulations,it is found that the autocorrelation features of obtained Legendre sequences and L1C codes are in accordance with theoretical results,which proves the correctness of the proposed method.

Reciprocity as an Ever-Present Dual Property of Everything

Reciprocity may be understood as relation of action and reaction in the sense of Hegel’s philosophical definition. Quoting Kant, freedom and ethical necessities are reciprocally limited. In this contribution, a more mathematical than philosophical reflection about reciprocity as an ever-present dual property of everything was given. As a crystallographer, the author is familiar with the action of Fourier transforms and the relation between a crystal lattice and its reciprocal lattice, already pointing to the duality between particles and waves. A generalization of the reciprocity term was stimulated by results of the famous Information Relativity (IR) theory of Suleiman with its proven physical manifestation of matter-wave duality, compared to the set-theoretical E-Infinity theory developed by El Naschie, where the zero set represents the pre-quantum particle, and the pre-quantum wave is assigned to the empty set boundary surrounding the pre-particle. Expectedly, the most irrational number of the golden mean is involved in these thoughts, because this number is intimately connected with its inverse. An important role plays further Hardy’s maximum quantum entanglement probability as the fifth power of φand its connection to the dark matter. Remembering, the eleven dimensions in Witten’s M-theory may be decomposed into the Lucas number L5 = 11 = φ−5 – φ5. Reciprocity is indeed omnipresent in our world as piloting waves that accompany all observable earthen and cosmic matter. As a side effect of the IR theory some fundamental constants such as the gyromagnetic factor of the electron, Sommerfeld’s fine-structure constant as well as the charge of the electron must be marginally changed caused by altered relativistic corrections. Consequences also arise for our vision about the evolution of life and consciousness.

Business English Talent Cultivation Research under the Background of Cross-border E-commerce

The meteoric rise of cross-border e-commerce has become one of the pillars of our foreign trade, while the lack of quali-fied talents in the industry may restrict its benign development. This paper analyzes the major problems existing in the BusinessEnglish talents cultivation in university, and offers advice for the construction of training modal for Business English talents basedon the cross-border e-commerce.

Problems in Cross-border E-commerce Export Trade in China ＆ Countermeasure Analysis

As an emerging industry in China, cross-border e-commerce has enjoyed the leap-forward development, along with increasingly prominent problems. This paper aims at finding out the problems and related roots that hinder its development, through conducting an analysis on the export development of cross-border e-commerce, in order to look for solutions and countermeasures in favor of its sound development and to promote the liberalization development of foreign trade in China.

Improved Channel Reciprocity for Secure Communication in Next Generation Wireless Systems

To secure the wireless connection between devices with low computational power has been a challenging problem due to heterogeneity in operating devices,device to device communication in Internet of Things(IoTs)and 5G wireless systems.Physical layer key generation(PLKG)tackles this secrecy problem by introducing private keys among two connecting devices through wireless medium.In this paper,relative calibration is used as a method to enhance channel reciprocity which in turn increases the performance of the key generation process.Channel reciprocity based key generation is emerged as better PLKG methodology to obtain secure wireless connection in IoTs and 5G systems.Circulant deconvolution is proposed as a promising technique for relative calibration to ensure channel reciprocity in comparison to existing techniques Total Least Square(TLS)and Structured Total Least Square(STLS).The proposed deconvolution technique replicates the performance of the STLS by exploiting the possibility of higher information reuse and its lesser computational complexity leads to less processing time in comparison to the STLS.The presented idea is validated by observing the relation between signalto-noise ratio(SNR)and the correlation coefficient of the corresponding channel measurements between communicating parties.

Dynamic Nonreciprocity with a Kerr Nonlinear Resonator

On-chip optical nonreciprocal devices are vital components for integrated photonic systems and scalable quantum information processing.Nonlinear optical isolators and circulators have attracted considerable attention because of their fundamental interest and their important advantages in integrated photonic circuits.However,optical nonreciprocal devices based on Kerr or Kerr-like nonlinearity are subject to dynamical reciprocity when the forward and backward signals coexist simultaneously in a nonlinear system.Here,we theoretically propose a method for realizing on-chip nonlinear isolators and circulators with dynamic nonreciprocity.Dynamic nonreciprocity is achieved via the chiral modulation on the resonance frequency due to coexisting self-and cross-Kerr nonlinearities in an optical ring resonator.This work showing dynamic nonreciprocity with a Kerr nonlinear resonator can be an essential step toward integrated optical isolation.

Reciprocity Relation between the Mass Constituents of the Universe and Hardy’s Quantum Entanglement Probability

In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-theoretical argumentation, the relation may also be a consequence of a coupling factor attributed to the normed dimensions of the universe. Also, very simple expressions for the mass amounts were obtained, when replacing the Golden Mean φ by the Archimedes’ constant π. A brief statement was devoted to the similarity between the E-Infinity Theory of El Naschie and the Information Relativity Theory of Suleiman. In addition, superconductivity was also linked with Hardy’s entanglement probability.

Application of dual reciprocity boundary element method to predict acoustic attenuation characteristics of marine engine exhaust silencers

In marine engine exhaust silencing systems, the presence of exhaust gas flow influences the sound propagation inside the systems and the acoustic attenuation performance of silencers. In order to investigate the effects of three-dimensional gas flow and acoustic damping on the acoustic attenuation characteristics of marine engine exhaust silencers, a dual reciprocity boundary element method (DRBEM) was developed. The acoustic governing equation in three-dimensional potential flow was derived first, and then the DRBEM numerical procedure is given. Compared to the conventional boundary element method (CBEM), the DRBEM considers the second order terms of flow Mach number in the acoustic governing equation, so it is suitable for the cases with higher Mach number subsonic flow. For complex exhaust silencers, it is difficult to apply the single-domain boundary element method, so a substructure approach based on the dual reciprocity boundary element method is presented. The experiments for measuring transmission loss of silencers are conducted, and the experimental setup and measurements are explained. The transmission loss of a single expansion chamber silencer with extended inlet and outlet were predicted by DRBEM and compared with the measurements. The good agreements between predictions and measurements are observed, which demonstrated that the derived acoustic governing equation and the DRBEM numerical procedure in the present study are correct.

The determinant of performance of cross-border M＆As in China： A comparative study between overseas Sino and Anglo firms

This study examines the factors that affect the performance of foreign acquiring firms in Chinese M＆As （mergers and acquisitions） market. Comparing between overseas Sino-Group and Anglo-Group, this study found that familiarity and location were the most important factors influencing performance of M＆A transactions in China. It also found that unrelated M＆A deals should be merged with familiarity for gaining positive acquisition performance. The total sample used in this study was 3,442 cases from October 1980 to March 2005. Because this period included all deals of M＆As after the opening of Chinese market in China. The authors＇ finding provided a more universal explanation in the cross-border M＆As in China.

Index system and methods for comprehensive assessment of cross-border power grid interconnection projects

With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a critical n eed to adopt scie ntific approaches in assessi ng cross-border power grid interconnection projects.First,con sidering the promotion of large-scale renewable energy resources and improvements in system adequacy,a comprehensive assessment index system,including costs,socio-economic benefits,environmental benefits,and technical benefits,is established in this study.Second,a synthetic assessment framework is proposed for cross-border power grid interconnection projects based on the index system comprising cost-benefit analysis,with market and network simulations,iterative methods for indicator weight evaluation,and technique for order preferenee by similarity to an ideal solution(TOPSIS)method for the project rankings.Fin ally,by assessi ng and comparing three cross-border projects betwee n Europe and Asia,the proposed index system and assessment framework have been proved to be effective and feasible;the results of this system can thus support investment decision-making related to such projects in the future.

China’s Cross-Border E-Commerce: Evolution Pattern and Influencing Factors

In recent years,while the traditional trade sectors have been shrinking,China’s cross-border e-commerce has undergone rapid development and has become a new driver of its international trade.Based on analysis of the evolution pattern of China’s cross-border e-commerce,this paper uses a revised gravity model to test empirically the driving factors and the resistance factors in the development of the country’s cross-border e-commerce.The results show that the total GDP,per capita disposable income of urban residents,total imports and exports,and the scale of the online shopping market have a positive relationship with cross-border e-commerce transactions,which are conducive to the development of cross-border e-commerce,while logistics costs inhibit the development of cross-border e-commerce.Accordingly,the paper puts forward several policy recommendations.