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Relationship between the unique microstructures and behaviors of high-entropy alloys 被引量:2
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作者 Yaqi Wu Peter KLiaw +5 位作者 Ruixuan Li Weiran Zhang Guihong Geng Xuehui Yan Guiqun Liu Yong Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1350-1363,共14页
High-entropy alloys(HEAs),which were introduced as a pioneering concept in 2004,have captured the keen interest of nu-merous researchers.Entropy,in this context,can be perceived as representing disorder and randomness... High-entropy alloys(HEAs),which were introduced as a pioneering concept in 2004,have captured the keen interest of nu-merous researchers.Entropy,in this context,can be perceived as representing disorder and randomness.By contrast,elemental composi-tions within alloy systems occupy specific structural sites in space,a concept referred to as structure.In accordance with Shannon entropy,structure is analogous to information.Generally,the arrangement of atoms within a material,termed its structure,plays a pivotal role in dictating its properties.In addition to expanding the array of options for alloy composites,HEAs afford ample opportunities for diverse structural designs.The profound influence of distinct structural features on the exceptional behaviors of alloys is underscored by numer-ous examples.These features include remarkably high fracture strength with excellent ductility,antiballistic capability,exceptional radi-ation resistance,and corrosion resistance.In this paper,we delve into various unique material structures and properties while elucidating the intricate relationship between structure and performance. 展开更多
关键词 high-entropy alloys unique microstructure special properties alloy design
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GLOBAL UNIQUE SOLUTIONS FOR THE INCOMPRESSIBLE MHD EQUATIONS WITH VARIABLE DENSITY AND ELECTRICAL CONDUCTIVITY
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作者 Xueli KE 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1747-1765,共19页
We study the global unique solutions to the 2-D inhomogeneous incompressible MHD equations,with the initial data(u0,B0)being located in the critical Besov space■and the initial densityρ0 being close to a positive co... We study the global unique solutions to the 2-D inhomogeneous incompressible MHD equations,with the initial data(u0,B0)being located in the critical Besov space■and the initial densityρ0 being close to a positive constant.By using weighted global estimates,maximal regularity estimates in the Lorentz space for the Stokes system,and the Lagrangian approach,we show that the 2-D MHD equations have a unique global solution. 展开更多
关键词 inhomogeneous MHD equations electrical conductivity global unique solutions
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WEAK-STRONG UNIQUENESS FOR THREE DIMENSIONAL INCOMPRESSIBLE ACTIVE LIQUID CRYSTALS
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作者 Fan YANG Congming LI 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1415-1440,共26页
The hydrodynamics of active liquid crystal models has attracted much attention in recent years due to many applications of these models.In this paper,we study the weak-strong uniqueness for the Leray-Hopf type weak so... The hydrodynamics of active liquid crystal models has attracted much attention in recent years due to many applications of these models.In this paper,we study the weak-strong uniqueness for the Leray-Hopf type weak solutions to the incompressible active liquid crystals in R^(3).Our results yield that if there exists a strong solution,then it is unique among the Leray-Hopf type weak solutions associated with the same initial data. 展开更多
关键词 analysis of parabolic and elliptic types weak-strong uniqueness active liquid crystals weak solution energy equality
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Local existence and uniqueness of solutions to the evolutionary model for magnetoviscoelasticity
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作者 YE Ting-ting WANG Guang-wu HUANG Gui-huo 《广州大学学报(自然科学版)》 CAS 2024年第4期77-90,共14页
In this paper,we prove the local existence and uniqueness of solutions to the evolutionary model for magnetoviscoelasticity in R^(2),R^(3).This model consists of an incompressible Navier-Stokes,a regularized system fo... In this paper,we prove the local existence and uniqueness of solutions to the evolutionary model for magnetoviscoelasticity in R^(2),R^(3).This model consists of an incompressible Navier-Stokes,a regularized system for the evolution of the deformation gradient and the Landau-Lifshitz-Gilbert system for the dynamics of the mag-netization.Our approach depends on approximating the system with a sequence of perturbed systems. 展开更多
关键词 the evolutionary model for magnetoviscoelasticity local solution uniqueNESS perturbed systems
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Understanding the superior mechanical properties of Mg-3Al-Zn alloy sheets:Role of multi-type unique textures
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作者 Jun Xu Jun Zhao +7 位作者 Bin Jiang Wenjun Liu Hong Yang Xintao Li Yuehua Kang Nan Zhou Kaihong Zheng Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1104-1112,共9页
Mg-3Al-1Zn(AZ31)sheets were produced by transverse gradient extrusion(TGE)process.The flow behavior and dynamic recrystallization during extrusion were systematically analyzed.The microstructures,textures,and mechanic... Mg-3Al-1Zn(AZ31)sheets were produced by transverse gradient extrusion(TGE)process.The flow behavior and dynamic recrystallization during extrusion were systematically analyzed.The microstructures,textures,and mechanical behavior of extruded AZ31 sheet were also analyzed and compared with conventional extruded(CE)sheet.The results showed that fine grain structure and multi-type unique textures were formed in TGE sheet because of the generation of extra flow velocity along transverse direction(TD)and flow velocity gradient along extrusion direction(ED)during extrusion.The basal poles gradually deviated away normal direction(ND)from edge to center of the TGE sheet along TD,and the largest inclination angle at center region reached around 65°.Furthermore,the basal poles inclined from ED to TD 40°-63°,except for the center region of TGE sheet.The TGE sheet presented higher ductility and strain hardening exponent(n-value),but lower yield strength and Lankford value(r-value)in comparison with the CE sheet.Both the basal<a>slip and tensile twins were easy to be activated during deformation,and the largest elongation of 41%and the lowest yield strength of 86.5 MPa were obtained for the ED-center sample in the TGE sheet. 展开更多
关键词 transverse gradient extrusion multi-type unique textures mechanical properties
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THE REGULARITY AND UNIQUENESS OF A GLOBAL SOLUTION TO THE ISENTROPIC NAVIER-STOKES EQUATION WITH ROUGH INITIAL DATA
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作者 王海涛 张雄韬 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1675-1716,共42页
A global weak solution to the isentropic Navier-Stokes equation with initial data around a constant state in the L^(1)∩BV class was constructed in[1].In the current paper,we will continue to study the uniqueness and ... A global weak solution to the isentropic Navier-Stokes equation with initial data around a constant state in the L^(1)∩BV class was constructed in[1].In the current paper,we will continue to study the uniqueness and regularity of the constructed solution.The key ingredients are the Holder continuity estimates of the heat kernel in both spatial and time variables.With these finer estimates,we obtain higher order regularity of the constructed solution to Navier-Stokes equation,so that all of the derivatives in the equation of conservative form are in the strong sense.Moreover,this regularity also allows us to identify a function space such that the stability of the solutions can be established there,which eventually implies the uniqueness. 展开更多
关键词 compressible Navier-Stokes equation BV initial data REGULARITY uniqueNESS
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UNIQUENESS OF INVERSE TRANSMISSION SCATTERING WITH A CONDUCTIVE BOUNDARY CONDITION BY PHASELESS FAR FIELD PATTERN
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作者 向建立 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期450-468,共19页
In this paper,we establish the unique determination result for inverse acoustic scattering of a penetrable obstacle with a general conductive boundary condition by using phaseless far field data at a fixed frequency.I... In this paper,we establish the unique determination result for inverse acoustic scattering of a penetrable obstacle with a general conductive boundary condition by using phaseless far field data at a fixed frequency.It is well-known that the modulus of the far field pattern is invariant under translations of the scattering obstacle if only one plane wave is used as the incident field,so it is impossible to reconstruct the location of the underlying scatterers.Based on some new research results on the impenetrable obstacle and inhomogeneous isotropic medium,we consider different types of superpositions of incident waves to break the translation invariance property. 展开更多
关键词 conductive boundary condition uniqueNESS phaseless far field data inverse scattering
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Uniquely Decomposable Constellation Group-Based Sparse Vector Coding for Short Packet Communications
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作者 Xuewan Zhang Hongyang Chen +3 位作者 Di Zhang Ganyu Qin Battulga Davaasambuu Takuro Sato 《China Communications》 SCIE CSCD 2023年第5期119-134,共16页
Sparse vector coding(SVC)is emerging as a potential technology for short packet communications.To further improve the block error rate(BLER)performance,a uniquely decomposable constellation group-based SVC(UDCG-SVC)is... Sparse vector coding(SVC)is emerging as a potential technology for short packet communications.To further improve the block error rate(BLER)performance,a uniquely decomposable constellation group-based SVC(UDCG-SVC)is proposed in this article.Additionally,in order to achieve an optimal BLER performance of UDCG-SVC,a problem to optimize the coding gain of UDCG-based superimposed constellation is formulated.Given the energy of rotation constellations in UDCG,this problem is solved by converting it into finding the maximized minimum Euclidean distance of the superimposed constellation.Simulation results demonstrate the validness of our derivation.We also find that the proposed UDCGSVC has better BLER performance compared to other SVC schemes,especially under the high order modulation scenarios. 展开更多
关键词 ultra-reliable and low latency communications sparse vector coding uniquely decomposable constellation group constellation rotation short packet communications
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THE EXISTENCE AND LOCAL UNIQUENESS OF MULTI-PEAK SOLUTIONS TO A CLASS OF KIRCHHOFF TYPE EQUATIONS
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作者 崔磊磊 郭佳星 李工宝 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1131-1160,共30页
In this paper,we study the existence and local uniqueness of multi-peak solutions to the Kirchhoff type equations-(ε^(2)a+εb∫_(R^(3))|■u|^(2))△u+V(x)u=u^(p),u>0 in R^(3),which concentrate at non-degenerate cri... In this paper,we study the existence and local uniqueness of multi-peak solutions to the Kirchhoff type equations-(ε^(2)a+εb∫_(R^(3))|■u|^(2))△u+V(x)u=u^(p),u>0 in R^(3),which concentrate at non-degenerate critical points of the potential function V(x),where a,b>0,1<p<5 are constants,andε>0 is a parameter.Applying the Lyapunov-Schmidt reduction method and a local Pohozaev type identity,we establish the existence and local uniqueness results of multi-peak solutions,which concentrate at{a_(i)}1≤i≤k,where{a_(i)}1≤i≤k are non-degenerate critical points of V(x)asε→0. 展开更多
关键词 Kirchhoff type equations potential functions having non-degenerate critical points the Lyapunov-Schmidt reduction method multi-peak solutions existence and local uniqueness
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Uniqueness of Viscosity Solutions to the Dirichlet Problem Involving Infinity Laplacian
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作者 Hong Sun Fang Liu 《Advances in Pure Mathematics》 2023年第10期662-673,共12页
In this paper, we study the Dirichlet boundary value problem involving the highly degenerate and h-homogeneous quasilinear operator associated with the infinity Laplacian, where the right hand side term is and the bou... In this paper, we study the Dirichlet boundary value problem involving the highly degenerate and h-homogeneous quasilinear operator associated with the infinity Laplacian, where the right hand side term is and the boundary value is . First, we establish the comparison principle by the double variables method based on the viscosity solutions theory for the general equation in. We propose two different conditions for the right hand side and get the comparison principle results under different conditions by making different perturbations. Then, we obtain the uniqueness of the viscosity solution to the Dirichlet boundary value problem by the comparison principle. Moreover, we establish the local Lipschitz continuity of the viscosity solution. 展开更多
关键词 Infinity Laplacian Comparison Principle uniqueNESS Local Lipschitz Continuity
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Existence and Uniqueness Results for a Fully Third-Order Boundary Value Problem
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作者 Xiaoming Liu Yongxiang Li 《Advances in Pure Mathematics》 2023年第8期495-503,共14页
The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have stud... The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have studied the boundary value problems of the complete third-order differential equations u′′′(t) = f (t,u(t),u′(t),u′′(t)). In this paper, we discuss the existence and uniqueness of solutions and positive solutions of the fully third-order ordinary differential equation on [0,1] with the boundary condition u(0) = u′(1) = u′′(1) = 0. Under some inequality conditions on nonlinearity f some new existence and uniqueness results of solutions and positive solutions are obtained. 展开更多
关键词 Fully Third-Order BVP SOLUTION Positive Solution Existence and uniqueness Inequality Conditions
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Strong Uniqueness of Best Approximations from RS-sets in Banach Spaces 被引量:1
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作者 何金苏 李冲 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期70-72,共3页
The problem of strong uniqueness of best approximation from an RS set in a Banach space is considered. For a fixed RS set G and an element x∈X , we proved that the best approximation g * to x from ... The problem of strong uniqueness of best approximation from an RS set in a Banach space is considered. For a fixed RS set G and an element x∈X , we proved that the best approximation g * to x from G is strongly unique. 展开更多
关键词 best approximation RS set strong uniqueness
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The Global Uniqueness of Solutions for a Class of Inverse Problem in 1-D Wave Equations of Hyperbolic Type 被引量:1
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作者 叶留青 司清亮 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期107-110,共4页
This paper has given the global uniquene ss theory of solutions for a class of inverse problem in 1_D Wave equation of hype rbolic type.
关键词 D Wave equations of hyperbolic inverse proble m global uniqueness
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Uniquely strongly clean triangular matrix rings
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作者 崔建 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期463-465,共3页
An element a of a ring R is called uniquely strongly clean if it is the sum of an idempotent and a unit that commute, and in addition, this expression is unique. R is called uniquely strongly clean if every element of... An element a of a ring R is called uniquely strongly clean if it is the sum of an idempotent and a unit that commute, and in addition, this expression is unique. R is called uniquely strongly clean if every element of R is uniquely strongly clean. The uniquely strong cleanness of the triangular matrix ring is studied. Let R be a local ring. It is shown that any n × n upper triangular matrix ring over R is uniquely strongly clean if and only if R is uniquely bleached and R/J(R) ≈Z2. 展开更多
关键词 uniquely strongly clean ring uniquely bleached local ring triangular matrix ring
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Application of Unique Resources in Recreational Agriculture of Hainan Island,China 被引量:1
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作者 周其良 《Journal of Landscape Research》 2011年第5期96-99,共4页
The development status and significance of recreational agriculture in Hainan were analyzed.By introducing advantages of Hainan Island in political institution,natural resources and humanistic resources,it was propose... The development status and significance of recreational agriculture in Hainan were analyzed.By introducing advantages of Hainan Island in political institution,natural resources and humanistic resources,it was proposed that special topographical scenery,Qiong Opera(Hainan Opera),tropical plants,rare animal species,customs of Li and Miao nationalities,and agricultural product resources could be applied in the development of recreational agriculture,and many activities of recreational agriculture could be organized. 展开更多
关键词 unique RESOURCES Investigation and evaluation APPLICATION RECREATIONAL AGRICULTURE
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Two Results on Uniquely r-Pancyclic Graphs 被引量:1
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作者 施永兵 孙家恕 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期56-60,共5页
In this paper,we prove that there does not exist an r-UPC[2]-graph for each r≥5 and there does not exist an r-UPC[C_t^2]-graph for each r≥3,where t is the number of bridges in a graph and C_t^2 is the number of comb... In this paper,we prove that there does not exist an r-UPC[2]-graph for each r≥5 and there does not exist an r-UPC[C_t^2]-graph for each r≥3,where t is the number of bridges in a graph and C_t^2 is the number of combinations of t bridges taken 2 at a time. 展开更多
关键词 graph theory cycle uniquely pancyclic graph r-UPC-graph -graph r-UPC[C_t^2]-graph
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Uniqueness of the Viscosity Solutions for the Initial Value Problem of One Type of Second Order Partial Differential Equation
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作者 刘长河 郇中丹 童明生 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期6-11,共6页
Aim To prove the uniqueness of the viscosity solutions for the initial value problems of one type of second order parabolic partial differential equations: Methods Using comparison theorem. Results and Conclusion If u... Aim To prove the uniqueness of the viscosity solutions for the initial value problems of one type of second order parabolic partial differential equations: Methods Using comparison theorem. Results and Conclusion If u0 is uniform continuousfunction in RN , F is continuous function in RNx(N) and F is degenerate elliptic, then thisequation has the sole viscosity solution. 展开更多
关键词 viscosity solution degenerate ellipticity the uniqueness of the solutions
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On existence and uniqueness of the solution of elastoplastic contact problems
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作者 郭小明 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期232-235,共4页
Contact problems and elastoplastic problems are unified and described by the variational inequality formulation, in which the constraints of the constitutional relations for elastoplastic materials and the contact con... Contact problems and elastoplastic problems are unified and described by the variational inequality formulation, in which the constraints of the constitutional relations for elastoplastic materials and the contact conditions are relaxed totally. First, the coerciveness of the functional is proved. Then the uniqueness of the solution of variational inequality for the elastoplastic contact problems is demonstrated. The existence of the solution is also demonstrated according to the sufficient conditions for the solution of the elliptic variational inequality. A mathematical foundation is developed for the variational extremum principle of elastoplastic contact problems. The developed variational extremum forms can give an effective and strict mathematical modeling to solve contact problems with mathematical programming. 展开更多
关键词 ELASTOPLASTIC contact problem EXISTENCE uniqueNESS COERCIVENESS variational extremum form
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A Note of the Uniqueness Criterion for Single Birth Processes
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作者 吴群英 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期88-92,共5页
This paper is devoted to studying the si ngle birth processes. The uniqueness criterion for the processes is presented.
关键词 single birth process uniqueness criterion zero _exit REGULAR
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Random but System-Wide Unique Unlinkable Parameters
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作者 Peter Schartner 《Journal of Information Security》 2012年第1期1-10,共10页
When initializing cryptographic systems or running cryptographic protocols, the randomness of critical parameters, like keys or key components, is one of the most crucial aspects. But, randomly chosen parameters come ... When initializing cryptographic systems or running cryptographic protocols, the randomness of critical parameters, like keys or key components, is one of the most crucial aspects. But, randomly chosen parameters come with the intrinsic chance of duplicates, which finally may cause cryptographic systems including RSA, ElGamal and Zero-Knowledge proofs to become insecure. When concerning digital identifiers, we need uniqueness in order to correctly identify a specific action or object. Unfortunately we also need randomness here. Without randomness, actions become linkable to each other or to their initiator’s digital identity. So ideally the employed (cryptographic) parameters should fulfill two potentially conflicting requirements simultaneously: randomness and uniqueness. This article proposes an efficient mechanism to provide both attributes at the same time without highly constraining the first one and never violating the second one. After defining five requirements on random number generators and discussing related work, we will describe the core concept of the generation mechanism. Subsequently we will prove the postulated properties (security, randomness, uniqueness, efficiency and privacy protection) and present some application scenarios including system-wide unique parameters, cryptographic keys and components, identifiers and digital pseudonyms. 展开更多
关键词 Randomness System-Wide uniqueness unique CRYPTOGRAPHIC PARAMETERS CRYPTOGRAPHIC keys DIGITAL Identifiers DIGITAL Pseudonyms UUID Universally unique Identifiers GUID Globally unique Identifiers
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