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THE ZERO LIMIT OF THERMAL DIFFUSIVITY FOR THE 2D DENSITY-DEPENDENT BOUSSINESQ EQUATIONS
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作者 叶霞 徐艳霞 王泽佳 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1800-1818,共19页
This paper is concerned with the asymptotic behavior of solutions to the initial boundary problem of the two-dimensional density-dependent Boussinesq equations.It is shown that the solutions of the Boussinesq equation... This paper is concerned with the asymptotic behavior of solutions to the initial boundary problem of the two-dimensional density-dependent Boussinesq equations.It is shown that the solutions of the Boussinesq equations converge to those of zero thermal diffusivity Boussinesq equations as the thermal diffusivity tends to zero,and the convergence rate is established.In addition,we prove that the boundary-layer thickness is of the valueδ(k)=k^(α)with anyα∈(0,1/4)for a small diffusivity coefficient k>0,and we also find a function to describe the properties of the boundary layer. 展开更多
关键词 density-dependent Boussinesq equation zero thermal diffusivity convergence rate boundary layer
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Zero distribution of some difference polynomials
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作者 LI Qian LIU Dan HUANG Zhi-bo 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期392-402,共11页
In this paper,suppose that a,c∈C{0},c_(j)∈C(j=1,2,···,n) are not all zeros and n≥2,and f (z) is a finite order transcendental entire function with Borel finite exceptional value or with infinitely ma... In this paper,suppose that a,c∈C{0},c_(j)∈C(j=1,2,···,n) are not all zeros and n≥2,and f (z) is a finite order transcendental entire function with Borel finite exceptional value or with infinitely many multiple zeros,the zero distribution of difference polynomials of f (z+c)-af^(n)(z) and f (z)f (z+c_1)···f (z+c_n) are investigated.A number of examples are also presented to show that our results are best possible in a certain sense. 展开更多
关键词 difference polynomial zero distribution Borel exceptional value
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Research on Data Tampering Prevention Method for ATC Network Based on Zero Trust
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作者 Xiaoyan Zhu Ruchun Jia +1 位作者 Tingrui Zhang Song Yao 《Computers, Materials & Continua》 SCIE EI 2024年第3期4363-4377,共15页
The traditional air traffic control information sharing data has weak security characteristics of personal privacy data and poor effect,which is easy to leads to the problem that the data is usurped.Starting from the ... The traditional air traffic control information sharing data has weak security characteristics of personal privacy data and poor effect,which is easy to leads to the problem that the data is usurped.Starting from the application of the ATC(automatic train control)network,this paper focuses on the zero trust and zero trust access strategy and the tamper-proof method of information-sharing network data.Through the improvement of ATC’s zero trust physical layer authentication and network data distributed feature differentiation calculation,this paper reconstructs the personal privacy scope authentication structure and designs a tamper-proof method of ATC’s information sharing on the Internet.From the single management authority to the unified management of data units,the systematic algorithm improvement of shared network data tamper prevention method is realized,and RDTP(Reliable Data Transfer Protocol)is selected in the network data of information sharing resources to realize the effectiveness of tamper prevention of air traffic control data during transmission.The results show that this method can reasonably avoid the tampering of information sharing on the Internet,maintain the security factors of air traffic control information sharing on the Internet,and the Central Processing Unit(CPU)utilization rate is only 4.64%,which effectively increases the performance of air traffic control data comprehensive security protection system. 展开更多
关键词 zero trust access policy air traffic information sharing network privacy data tam-per-proof certification features
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A Cross-Sectional Study on the Impact of Operation Triple Zero (OTZ) Program on Viral Load Suppression amongst Members of the Adolescent Club in 68 Nigerian Army Reference Hospital Yaba Lagos, Nigeria
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作者 Nkechinyere Harrison Ismail Lawal +7 位作者 Yakubu Adamu Kehinde Aribisala Adegbenga Olarinoye Uzoamaka Agbaim Funmilayo Owolabi Dooshima Okonkwo Laura Chittenden Nathan Okeji 《World Journal of AIDS》 2024年第2期35-44,共10页
Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national ... Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national challenges with poor viral suppression. The OTZ program aligns with the UNAIDS 95-95-95 goals. It seeks to empower AYPLHIV to be in charge of their treatment and commit to triple zero outcomeszero missed appointments, zero missed drugs, and zero viral loads. The purpose of the study was to assess the impact of the OTZ program on viral load suppression among members of the adolescent club in 68 NARHY, Lagos. Method: A cross-sectional retrospective study to evaluate the impact of the OTZ program on the viral load of 53 AYP enrolled in the OTZ program between March 2019 to December 2019 was analyzed. The Percentage of viral load suppression before enrollment compared with 6 and 12 months after enrollment into the OTZ program. The AYP is grouped into 10 - 14, 15 - 19, and 20 - 24 years. Activities conducted were peer driven monthly meetings with the AYP during which the adolescents interacted on issues relating to improving their treatment outcomes, healthcare workers reviewed their clinical status, viral load result, provider peer counseling, and caregivers engagement to support adherence to medication and ARV refills. Results: Before OTZ, 81% aged 10 - 14 years, 75% aged 15 - 19 years, and 25% aged 20 - 24 years were virally suppressed (VL less than 1000 copies/ml). Six months after enrollment, 94% were virally suppressed95% aged 10 - 14 years, 96% aged 15 - 19 years, and 66% aged 20-24 years. Twelve months after enrollment, 96% of AYP were virally suppressed100% aged 10-14 years, 93% aged 15 - 19 years, and 100% aged 20 - 24 years. Males viral load (VL) suppression improved from 79% to 96% and 92%, while females VL suppression improved from 69% to 93% and 100% at 6 and 12 months respectively. Conclusion: The OTZ activities contributed to improved viral load suppression in the AYP of the facility. 展开更多
关键词 Impact Operation Triple zero ADOLESCENT Viral Load NIGERIA
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Algorithm for Visualization of Zero Divisor Graphs of the Ring ℤn Using MAPLE Coding
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作者 Nasir Ali 《Open Journal of Discrete Mathematics》 2024年第1期1-8,共8页
This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study ... This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study of ring theory, depict relationships between elements of a ring that multiply to zero. The paper explores the development and implementation of algorithms in MAPLE for constructing these ZDGs. The comparative study aims to discern the strengths, limitations, and computational efficiency of different MAPLE algorithms for creating zero divisor graphs offering insights for mathematicians, researchers, and computational enthusiasts involved in ring theory and mathematical computations. 展开更多
关键词 zero Divisor Graph Ring Theory Maple Algorithm n Modulo n Graph Theory Mathematical Computing
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From Standard Policy-Based Zero Trust to Absolute Zero Trust (AZT): A Quantum Leap to Q-Day Security
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作者 Fazal Raheman 《Journal of Computer and Communications》 2024年第3期252-282,共31页
Cybercrime is projected to cost a whopping $23.8 Trillion by 2027. This is essentially because there’s no computer network that’s not vulnerable. Fool-proof cybersecurity of personal data in a connected computer is ... Cybercrime is projected to cost a whopping $23.8 Trillion by 2027. This is essentially because there’s no computer network that’s not vulnerable. Fool-proof cybersecurity of personal data in a connected computer is considered practically impossible. The advent of quantum computers (QC) will worsen cybersecurity. QC will be a boon for data-intensive industries by drastically reducing the computing time from years to minutes. But QC will render our current cryptography vulnerable to quantum attacks, breaking nearly all modern cryptographic systems. Before QCs with sufficient qubits arrive, we must be ready with quantum-safe strategies to protect our ICT infrastructures. Post-quantum cryptography (PQC) is being aggressively pursued worldwide as a defence from the potential Q-day threat. NIST (National Institute of Standards and Technology), in a rigorous process, tested 82 PQC schemes, 80 of which failed after the final round in 2022. Recently the remaining two PQCs were also cracked by a Swedish and a French team of cryptographers, placing NIST’s PQC standardization process in serious jeopardy. With all the NIST-evaluated PQCs failing, there’s an urgent need to explore alternate strategies. Although cybersecurity heavily relies on cryptography, recent evidence indicates that it can indeed transcend beyond encryption using Zero Vulnerability Computing (ZVC) technology. ZVC is an encryption-agnostic absolute zero trust (AZT) approach that can potentially render computers quantum resistant by banning all third-party permissions, a root cause of most vulnerabilities. Unachievable in legacy systems, AZT is pursued by an experienced consortium of European partners to build compact, solid-state devices that are robust, resilient, energy-efficient, and with zero attack surface, rendering them resistant to malware and future Q-Day threats. 展开更多
关键词 CYBERSECURITY Quantum Computers Post Quantum Cryptography Q-Day zero Trust
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High Temperature Rheological Performance of Graphene Modified Rubber Asphalt
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作者 Heyuan GUO Chunhua LI +3 位作者 Xin ZHAO Yinghua YUAN Shaoqi TANG Yongjun MENG 《Research and Application of Materials Science》 2024年第1期9-15,共7页
To elucidate the high temperature rheological capability of graphene modified rubber asphalt,three contents of graphene and crumb rubber were prepared by a combination of mechanical agitation and high speed shearing m... To elucidate the high temperature rheological capability of graphene modified rubber asphalt,three contents of graphene and crumb rubber were prepared by a combination of mechanical agitation and high speed shearing machine,then used dynamic shear rheological test(DSR)and multiple stress creep recovery(MSCR)tests to evaluate.The hardness and softening point with rotational viscosity of samples raised with the addition of graphene,especially the addition of 0.04%.Dynamic shear rheological test revealedthat the dynamic shear modulus G*,rutting factor G*/Sin δ,and zero shear viscosity(ZSV)of graphene-modified rubber asphalt were greatly influenced along with graphene-increased,on the contrary,phase angle δ which characterize the viscoelastic ratio of asphalt decreased.Multiple stress creep recovery(MSCR)tests showed that the graphene-enhanced rubber asphalt had high-temperature stability through non-recoverable creep compliance(Jnr).Based on these findings,graphene-modified rubber asphalt binders with the addition of 0.04% graphene had good viscoelastic properties as well as high temperature rutting resistance performance.In the meantime,G*/Sin δ,ZSV,and Jnr100,Jnr3200 have good correlation,which can reveal the excellent high-temperature stability performance of asphalt. 展开更多
关键词 GRAPHENE High Temperature rheological properties MSCR zero shear viscosity RUTTING
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Zero通道下MISS TLIF联合Zina钉治疗腰椎间盘突出症 被引量:2
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作者 史柏娜 赵敏 +5 位作者 周江军 付美清 肖春林 程彬 余专一 程球新 《临床骨科杂志》 2016年第6期669-671,共3页
目的:探讨Zero通道下微创经椎间孔入路行椎管减压、椎间融合( MISS TLIF)联合Zina钉治疗腰椎间盘突出症的临床疗效。方法对55例腰椎间盘突出症患者采用后路切口经多裂肌肉间隙入路、经Zero 通道下行MISS TLIF联合Zina钉技术治疗。其... 目的:探讨Zero通道下微创经椎间孔入路行椎管减压、椎间融合( MISS TLIF)联合Zina钉治疗腰椎间盘突出症的临床疗效。方法对55例腰椎间盘突出症患者采用后路切口经多裂肌肉间隙入路、经Zero 通道下行MISS TLIF联合Zina钉技术治疗。其中单侧减压49例,双侧减压5例,单侧入路双侧减压1例。采用Nakai分级评定临床疗效。结果患者均获得随访,时间6-18个月。患者腰痛和下肢放射性麻木等临床症状均有效缓解,临床疗效按Nakai分级评定:优25例,良29例,可1例,优良率为98.18%。结论 Zero通道下MISS TLIF联合Zina钉治疗腰椎间盘突出症能显著缓解患者症状,改善功能,近期疗效好。 展开更多
关键词 腰椎间盘突出症 zero通道 微创经椎间孔腰椎间融合术 Zina
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ZEROS OF ENTIRE SOLUTIONS TO COMPLEX LINEAR DIFFERENCE EQUATIONS 被引量:7
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作者 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1141-1148,共8页
In this article, we study the complex oscillation problems of entire solutions to homogeneous and nonhomogeneous linear difference equations, and obtain some relations of the exponent of convergence of zeros and the o... In this article, we study the complex oscillation problems of entire solutions to homogeneous and nonhomogeneous linear difference equations, and obtain some relations of the exponent of convergence of zeros and the order of growth of entire solutions to complex linear difference equations. 展开更多
关键词 Linear difference equation complex oscillation zero order of growth
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Some results on zeros and uniqueness of difference-differential polynomials 被引量:4
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作者 LIU Kai LIU Xin-ling CAO Ting-bin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第1期94-104,共11页
We consider the zeros distributions of difference-differential polynomials which are the derivatives of difference products of entire functions. We also investigate the uniqueness problems of difference-differential p... We consider the zeros distributions of difference-differential polynomials which are the derivatives of difference products of entire functions. We also investigate the uniqueness problems of difference-differential polynomials of entire functions sharing a common value. 展开更多
关键词 zero sharing value UNIQUENESS difference-differential polynomial.
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ON ZEROS OF SOLUTIONS OF HIGHER ORDER HOMOGENEOUS LINEAR DIFFERENTIAL EQUATIONS 被引量:2
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作者 蓝双婷 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期556-564,共9页
In this article, we investigate the exponent of convergence of zeros of solutions for some higher-order homogeneous linear differential equation, and prove that if Ak-1 is the dominant coefficient, then every transcen... In this article, we investigate the exponent of convergence of zeros of solutions for some higher-order homogeneous linear differential equation, and prove that if Ak-1 is the dominant coefficient, then every transcendental solution f(z) of equation……satisfies )λ(f) =∞, where A(f) denotes the exponent of convergence of zeros of the meromor- phic function f(z). 展开更多
关键词 Differential equation exponent of convergence of zeros TYPE
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Relative energy zero ratio-based approach for identifying pulse-like ground motions 被引量:2
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作者 Liu Ping Li Ning +2 位作者 Ma Hua Xie Lili Zhou Baofeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期1-16,共16页
Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault re... Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault regions. In this study, a new method for identifying the velocity pulses is proposed, based on different trends of two parameters: the short-time energy and the short-time zero crossing rate of a ground motion record. A new pulse indicator, the relative energy zero ratio(REZR), is defined to qualitatively identify pulse-like features. The threshold for pulse-like ground motions is derived and compared with two other identification methods through statistical analysis. The proposed procedure not only shows good accuracy and efficiency when identifying pulse-like ground motions but also exhibits good performance for classifying records with high-frequency noise and discontinuous pulses. The REZR method does not require a waveform formula to express and fit the potential velocity pulses;it is a purely signal-based classification method. Finally, the proposed procedure is used to evaluate the contribution of pulse-like motions to the total input energy of a seismic record, which dramatically increases the seismic damage potential. 展开更多
关键词 pulse-like ground motion velocity pulse relative energy zero-crossing ratio short-time input energy shorttime zero crossing rate
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ZEROS AND FIXED POINTS OF DIFFERENCE OPERATORS OF MEROMORPHIC FUNCTIONS 被引量:1
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作者 崔巍巍 杨连忠 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期773-780,共8页
Let f be a transcendental meromorphic function and △f(z) = f(z + 1) -- f(z) A number of results are proved concerning the existences of zeros and fixed points of Af(z) and △f(z)/f(z) when f(z) is of o... Let f be a transcendental meromorphic function and △f(z) = f(z + 1) -- f(z) A number of results are proved concerning the existences of zeros and fixed points of Af(z) and △f(z)/f(z) when f(z) is of order σ(f)=1. Examples show that some of the results are sharp. 展开更多
关键词 Entire functions meromorphic functions complex difference fixed points zeroS
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DISTRIBUTION OF ZEROS OF SOLUTIONS OF FIRST ORDER DELAY DIFFERENTIAL EQUATIONS 被引量:4
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作者 Tang Xianhua\ Yu Jianshe 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1999年第4期375-380,共6页
The paper gives two estimates of the distance between adjacent zeros of solutions of the first\|order delay differential equation x′(t)+p(t)x(t-τ) =0 in the case when p(t)≥0 and ∫ t t-τ p(s)d s-1e ... The paper gives two estimates of the distance between adjacent zeros of solutions of the first\|order delay differential equation x′(t)+p(t)x(t-τ) =0 in the case when p(t)≥0 and ∫ t t-τ p(s)d s-1e oscillates or p(t) itself oscillates. 展开更多
关键词 Delay differentialequation distance betw een adjacent zeros estim ation
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Zero drift and solid Earth tide extracted from relative gravimetric data with principal component analysis 被引量:1
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作者 Yu Hongjuan Guo Jinyun +2 位作者 Li Jiulong Mu Dapeng Kong Qiaoli 《Geodesy and Geodynamics》 2015年第2期143-150,共8页
Zero drift and solid Earth tide corrections to static relative gravirnetric data cannot be ignored. In this paper, a new principal component analysis (PCA) algorithm is presented to extract the zero drift and the so... Zero drift and solid Earth tide corrections to static relative gravirnetric data cannot be ignored. In this paper, a new principal component analysis (PCA) algorithm is presented to extract the zero drift and the solid Earth tide, as signals, from static relative gravimetric data assuming that the components contained in the relative gravimetric data are uncorrelated. Static relative gravity observations from Aug. 15 to Aug. 23, 2014 are used as statistical variables to separate the signal and noise with PCA to obtain desired signals. The results of the linear drift extracted by PCA are consistent with those calculated by the least squares linear fitting, and the differences only reach to 10-2μGal/day order of magnitude. Furthermore, PCA is used to estimate the solid Earth tide from the relative gravimetric data corrected by the zero drift. The statistical results are consistent with the results derived from the solid Earth tide correction provided by the internal software of the CG-5 gravimeter (SCINTREX Limited Ontario Canada). The statistical results of the differences between the two methods are both less than 8 ,Gal, and the RMSs for 9 days are all less than 5 μGal. 展开更多
关键词 Principal component analysis zero drift Solid Earth tide Relative gravimetry CG-5 gravimeter
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ON SETS OF ZEROES OF CLIFFORD ALGEBRA-VALUED POLYNOMIALS 被引量:1
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作者 杨燕 钱涛 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期1004-1012,共9页
In this note, we study zeroes of Clifford algebra-valued polynomials. We prove that if such a polynomial has only real coefficients, then it has two types of zeroes: the real isolated zeroes and the spherical conjuga... In this note, we study zeroes of Clifford algebra-valued polynomials. We prove that if such a polynomial has only real coefficients, then it has two types of zeroes: the real isolated zeroes and the spherical conjugate ones. The total number of zeroes does not exceed the degree of the polynomial. We also present a technique for computing the zeroes. 展开更多
关键词 Clifford algebra zeroes of polynomials
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PERTURBATIONS OF ZEROS OF SOLUTIONS TO SECOND ORDER DIFFERENTIAL EQUATIONS WITH POLYNOMIAL COEFFICIENTS
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作者 Michael Gil' 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1083-1092,共10页
Let P(z) and P(z) be polynomials of the same degree. We consider the equations u" = P(z)u and u" = P(z)u (z ∈ C) whose solutions are u(z) and u(z), respectively. Let Zk(U) and zk(u), k = 1, 2,...,... Let P(z) and P(z) be polynomials of the same degree. We consider the equations u" = P(z)u and u" = P(z)u (z ∈ C) whose solutions are u(z) and u(z), respectively. Let Zk(U) and zk(u), k = 1, 2,..., be the zeros of u(z) and u(z), respectively. We derive bounds for the quantity sup j inf k|1/zk(u)-1/zj(u)| 展开更多
关键词 Complex differential equation zeros of solutions perturbation of zeros
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ZERO KINEMATIC VISCOSITY-MAGNETIC DIFFUSION LIMIT OF THE INCOMPRESSIBLE VISCOUS MAGNETOHYDRODYNAMIC EQUATIONS WITH NAVIER BOUNDARY CONDITIONS
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作者 栗付才 张志朋 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1503-1536,共34页
We investigate the uniform regularity and zero kinematic viscosity-magnetic diffusion limit for the incompressible viscous magnetohydrodynamic equations with the Navier boundary conditions on the velocity and perfectl... We investigate the uniform regularity and zero kinematic viscosity-magnetic diffusion limit for the incompressible viscous magnetohydrodynamic equations with the Navier boundary conditions on the velocity and perfectly conducting conditions on the magnetic field in a smooth bounded domain Ω⊂R^(3).It is shown that there exists a unique strong solution to the incompressible viscous magnetohydrodynamic equations in a finite time interval which is independent of the viscosity coefficient and the magnetic diffusivity coefficient.The solution is uniformly bounded in a conormal Sobolev space and W^(1,∞)(Ω)which allows us to take the zero kinematic viscosity-magnetic diffusion limit.Moreover,we also get the rates of convergence in L^(∞)(0,T;L^(2)),L^(∞)(0,T;W^(1,p))(2≤p<∞),and L^(∞)((0,T)×Ω)for some T>0. 展开更多
关键词 incompressible viscous MHD equations ideal incompressible MHD equations Navier boundary conditions zero kinematic viscosity-magnetic diffusion limit
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The Zeros of a Certain Homogeneous Difference Polynomials of Meromorphic Functions
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作者 Qian Lu Qilong Liao 《Advances in Pure Mathematics》 2013年第1期99-104,共6页
Let f(z) be a function transcendental and meromorphic in the plane of growth order less than 1. This paper focuses on discuss and estimate the number of the zeros of a certain homogeneous difference polynomials of deg... Let f(z) be a function transcendental and meromorphic in the plane of growth order less than 1. This paper focuses on discuss and estimate the number of the zeros of a certain homogeneous difference polynomials of degree k in f(z), and obtains that this certain homogeneous difference polynomials has infinitely many zeros. 展开更多
关键词 MEROMORPHIC Functions zeroS HOMOGENEOUS DifFERENCE POLYNOMIALS
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CHEBYSHEV APPROXIMATION OF THE SECOND KIND OF MODIFIED BESSEL FUNCTION OF ORDER ZERO
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作者 张璟 周哲玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第5期483-487,共5页
The second kind of modified Bessel function of order zero is the solutions of many problems in engineering. Modified Bessel equation is transformed by exponential transformation and expanded by J.P.Boyd's rational... The second kind of modified Bessel function of order zero is the solutions of many problems in engineering. Modified Bessel equation is transformed by exponential transformation and expanded by J.P.Boyd's rational Chebyshev basis. 展开更多
关键词 second kind of modified Bessel function of order zero exponential transformation rational Chebyshev basis
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