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LARCH BARK TANNIN ADHESIVE FOR EXTERIOR PARTICLEBOARD
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作者 刘志群 李晓平 +1 位作者 陆仁书 翁向丽 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第4期79-82,共4页
The larch bark tannins were used to make adhesive for particleboard. The tanninadhesive in which 60% phcnol was replaced by tannin has 1 - 1 .5 month storage life and its cost is lower than that of PF resin. At the 10... The larch bark tannins were used to make adhesive for particleboard. The tanninadhesive in which 60% phcnol was replaced by tannin has 1 - 1 .5 month storage life and its cost is lower than that of PF resin. At the 10% and 9% rcsin solids content on dry wood chips, larch particleboard and poplar particleboard were made respectively. The physical properties of boards can meet the nccds of cxterior particleboard in German Standard DIN68763 V 100. 展开更多
关键词 LARCH BARK TANNIN exterior partICLEBOARD ADHESIVE
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An impact sensitivity assessment method of spacecraft based on virtual exterior wall
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作者 Runqiang Chi Yuyan Liu +1 位作者 Diqi Hu Baojun Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期142-157,共16页
The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft... The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft.An impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational efficiency.This method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the spacecraft.The Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh quality.The influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and spacecraft.The results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the method.The PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size vs.flux relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft. 展开更多
关键词 Sensitivity OD/M SPACECRAFT Virtual exterior wall
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Exterior Quality and Physical Properties of Hongda Tobacco in Yunnan Province 被引量:6
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作者 薛红芬 胡魏耀 +3 位作者 王娟 徐安传 周丽娟 资文华 《Agricultural Science & Technology》 CAS 2012年第4期751-754,共4页
[Objective] The aim was to analyze the exterior quality and physical prop- erties of Hongda Tobacco in Yunnan Province, thus providing references for planting planning, technology and selection of raw materials. [Meth... [Objective] The aim was to analyze the exterior quality and physical prop- erties of Hongda Tobacco in Yunnan Province, thus providing references for planting planning, technology and selection of raw materials. [Method] Hongda C3F progenies were chosen from 24 villages and towns in Qujing, Kunming, Baoshan and Dali, and the concerning exterior quality and physical properties were analyzed through cluster analysis. [Result] The openness and width of C3F differed significantly among Qujing, Kunming, Baoshan and Dali. The thickness, stem content, equilibrium moisture con- tent extremely differed, and density and filling power varied significantly. Most physi- cal properties, such as equilibrium moisture content and density, of Dali Hongda were quite different from those in Qujing, Kunming and Baoshan, indicating that Dali Hongda enjoys special characteristics in physical properties. In addition, stem content in east, center and west areas of Yunnan Province differed significantly and Hongda in Yunnan could be classified into four species according to physical property. [Conclusion] The research has laid basis for planting planning, technology and raw mate- rials selection of Hongda tobacco. 展开更多
关键词 Hongda exterior quality:Physical properties:Local characteristics
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Control of exterior ballistic properties of spin-stabilized bullet by optimizing internal mass distribution 被引量:3
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作者 Janne Lahti Timo Sailaranta +1 位作者 Mikko Harju Kai Virtanen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第1期38-50,共13页
This paper introduces a novel approach for controlling the exterior ballistic properties of spin-stabilized bullets by optimizing their internal mass distributions. Specifically, the properties of interest are the bul... This paper introduces a novel approach for controlling the exterior ballistic properties of spin-stabilized bullets by optimizing their internal mass distributions. Specifically, the properties of interest are the bullets’ stability characteristics that are examined through dynamic and gyroscopic stability parameters.New analytical expressions for aerodynamic quantities are also derived to address the compressibility of air. These expressions are utilized in a bullet model that enables efficient computation of the stability parameters for a given mass distribution. The bullet model is used in the formulation of nonlinear optimization problems that provide optimal mass distributions with respect to given goals, i.e., desired stability characteristics. The bullet types investigated in this paper are a long range bullet and a limited range training bullet. In the optimization of the mass distribution of the long range bullet, the goal is that the bullet stays stable for as long as possible. The mass distribution of the training bullet is optimized such that the bullet is stable at launch but becomes unstable shortly afterwards. The global optimal solutions obtained with the new approach fulfill the desired stability characteristics better than currently used uniformly filled bullets. Overall, the optimization approach reveals a new goal focused philosophy for bullet design compared to current trial and error design practices. 展开更多
关键词 AERODYNAMICS BULLET exterior BALLISTICS Mass properties Optimization Stability
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Numerical Simulation of Antennae by Discrete Exterior Calculus 被引量:1
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作者 XIE Zheng YE Zheng MA Yu-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1067-1070,共4页
Numerical simulation of antennae is a topic in computational electromagnetism,which is concerned withthe numerical study of Maxwell equations.By discrete exterior calculus and the lattice gauge theory with coefficient... Numerical simulation of antennae is a topic in computational electromagnetism,which is concerned withthe numerical study of Maxwell equations.By discrete exterior calculus and the lattice gauge theory with coefficient R,we obtain the Bianchi identity on prism lattice.By defining an inner product of discrete differential forms,we derivethe source equation and continuity equation.Those equations compose the discrete Maxwell equations in vacuum caseon discrete manifold,which are implemented on Java development platform to simulate the Gaussian pulse radiation onantennaes. 展开更多
关键词 discrete exterior calculus discrete variation Maxwell equations lattice gauge theory ANTENNAE
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EXISTENCE AND NONEXISTENCE OF GLOBAL POSITIVE SOLUTIONS FOR DEGENERATE PARABOLIC EQUATIONS IN EXTERIOR DOMAINS 被引量:1
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作者 曾宪忠 刘振海 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期713-725,共13页
This article deals with the degenerate parabolic equations in exterior domains and with inhomogeneous Dirichlet boundary conditions. We obtain that pc = (σ + m )n / ( n-σ- 2 ) is its critical exponent provided ... This article deals with the degenerate parabolic equations in exterior domains and with inhomogeneous Dirichlet boundary conditions. We obtain that pc = (σ + m )n / ( n-σ- 2 ) is its critical exponent provided max{-1, [ (1- m )n- 2] / ( n + l ) } 〈 σ 〈 n- 2. This critical exponent is not the same as that for the corresponding equations with the boundary value 0, but is more closely tied to the critical exponent of the elliptic type degenerate equations. Futhermore, we demonstrate that if max(1, σ + m) 〈 p 〈 pc, then every positive solution of the equations blows up in finite time; whereas for p 〉 pc, the equations admit global positive solutions for some boundary values and initial data. Meantime, we also demonstrate that its positive solutions blow up in finite time provided n〈σ+2. 展开更多
关键词 Degenerate parabolic equations exterior domains -inhomogeneous dirichlet boundary conditions critical exponent BLOW-UP global existence
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ON THE UNIQUENESS OF BOUNDARY INTEGRAL EQUATION FOR THE EXTERIOR HELMHOLTZ PROBLEM 被引量:1
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作者 王清 徐博侯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第10期965-971,共7页
From the point of view of energy analysis, the cause that the uniqueness of the boundary integral equation induced from the exterior Helmholtz problem does not hold is investigated in this paper. It is proved that the... From the point of view of energy analysis, the cause that the uniqueness of the boundary integral equation induced from the exterior Helmholtz problem does not hold is investigated in this paper. It is proved that the Sommerfeld's condition at the infinity is changed so that it is suitable not only for the radiative wave but also for the absorptive wave when we use the boundary integral equation to describe the exterior Helmholtz problem. There fore, the total energy of the system is conservative. The mathematical dealings to guarantee the uniqueness are discussed based upon this explanation. 展开更多
关键词 exterior Helmholtz problem boundary integral equation UNIQUENESS
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FAST AND SLOW DECAY SOLUTIONS FOR SUPERCRITICAL FRACTIONAL ELLIPTIC PROBLEMS IN EXTERIOR DOMAINS 被引量:1
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作者 AO Wei-wei LIU Chao WANG Li-ping 《数学杂志》 2020年第5期508-510,共3页
1 Introduction and Main Results We construct classic solutions of the following supercritical nonlinear fractional exterior problem.
关键词 problem. exterior FRACTIONAL
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Solving the time-dependent Schrödinger equation by combining smooth exterior complex scaling and Arnoldi propagator 被引量:1
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作者 Shun Wang Wei-Chao Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期227-234,共8页
Abstract We develop a highly efficient scheme for numerically solving the three-dimensional time-dependent Schrödinger equation of the single-active-electron atom in the field of laser pulses by combining smooth ... Abstract We develop a highly efficient scheme for numerically solving the three-dimensional time-dependent Schrödinger equation of the single-active-electron atom in the field of laser pulses by combining smooth exterior complex scaling(SECS)absorbing method and Arnoldi propagation method.Such combination has not been reported in the literature.The proposed scheme is particularly useful in the applications involving long-time wave propagation.The SECS is a wonderful absorber,but its application results in a non-Hermitian Hamiltonian,invalidating propagators utilizing the Hermitian symmetry of the Hamiltonian.We demonstrate that the routine Arnoldi propagator can be modified to treat the non-Hermitian Hamiltonian.The efficiency of the proposed scheme is checked by tracking the time-dependent electron wave packet in the case of both weak extreme ultraviolet(XUV)and strong infrared(IR)laser pulses.Both perfect absorption and stable propagation are observed. 展开更多
关键词 time-dependent Schrödinger equation(TDSE) smooth exterior complex scaling(SECS)absorb-ing method Arnoldi propagator
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THE COUPLING OF BOUNDARY ELEMENT AND FINITE ELEMENT METHODS FOR THE EXTERIOR NONSTATIONARY NAVIER-STOKES EQUATIONS 被引量:2
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作者 何银年 李开泰 《Acta Mathematica Scientia》 SCIE CSCD 1991年第2期190-207,共18页
In this paper, we represent a new numerical method for solving the nonstationary Stokes equations in an unbounded domain. The technique consists in coupling the boundary integral and finite element methods. The variat... In this paper, we represent a new numerical method for solving the nonstationary Stokes equations in an unbounded domain. The technique consists in coupling the boundary integral and finite element methods. The variational formulation and well posedness of the coupling method are obtained. The convergence and optimal estimates for the approximation solution are provided. 展开更多
关键词 THE COUPLING OF BOUNDARY ELEMENT AND FINITE ELEMENT METHODS FOR THE exterior NONSTATIONARY NAVIER-STOKES EQUATIONS
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Three dimensional simulation of electromagnetic railgun's exterior ballistics
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作者 金锋 陆晓菲 陈砚桥 《Journal of Beijing Institute of Technology》 EI CAS 2013年第4期492-496,共5页
In order to evaluate the electromagnetic railgun' s practical combat capability as well as its tactic application prospects, a three dimensional simulation model of electromagnetic railgun' s exterior ballistics is ... In order to evaluate the electromagnetic railgun' s practical combat capability as well as its tactic application prospects, a three dimensional simulation model of electromagnetic railgun' s exterior ballistics is presented. On the hypothesis of the Earth' s being round and ignoring the influ- ence of rotation, the railgun' s atmospheric environment and its motion equations are established by the Simulink Module of Matlab. And the railgun' s characteristics of exterior ballistic under different muzzle energy and emission inclinations are discussed. Results show that its incomparable superiori- ty in improving range and lethality to conventional artillery under the same launch condition based on railgun' s range and variation of velocities. It is useful for the efficacy evaluation of railgun' s combat capability and its practical applications in fields such as ground war, missile interception and so on. 展开更多
关键词 RAILGUN exterior ballistics SIMULATION MATLAB
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Experimental Studies on Seismic Behavior of Exterior SRUHSC Joints
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作者 Wei Liu Jinqing Jia 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第5期61-70,共10页
To investigate the seismic behavior of the joints,six steel reinforced ultra high strength concrete( SRUHSC) frame exterior joints were tested. Three levels of axial compressive ratio varying from 0.25 to 0.45 were in... To investigate the seismic behavior of the joints,six steel reinforced ultra high strength concrete( SRUHSC) frame exterior joints were tested. Three levels of axial compressive ratio varying from 0.25 to 0.45 were investigated to determine how this variable might influence the performance of the joints including failure mode,ductility,energy dissipation capacity,stiffness degradation,shear strength and shear deformation by the quasi-static cyclic test on SRUHSC exterior joints. This research program suggests that the design of joint should make full use of the joint panel deformation to dissipate energy of earthquake. It is tested that the value of 0.38 as a dividing point about the effect of axial compression ratio on the seismic performance of SRUHSC exterior joints should be taken into account in design. In addition,the increase of volumetric ratio of stirrup could possess the ductility for adequate response to unexpected strong earthquakes and a recommended value of minimum volumetric ratio of stirrup with high axial-load level is pointed out. 展开更多
关键词 exterior JOINTS ultra high strength CONCRETE steel AXIAL compression RATIO
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Fitting on elements of exterior orientation utilizing SPOT-5 raw data file
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作者 SONG Wei-dong~1, WANG Wei-xi~1, HU Xing-hua~2 (1. Liaoning Technical University, Fuxin 123000, China 2. Liaoning Technical University, Fuxin 123000, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期35-37,共3页
In traditional pattern, the calculation of elements of exterior orientation is to calculate the elements of image forming moment by using fundamental ground control points. Utilizing satellite raw data file directly, ... In traditional pattern, the calculation of elements of exterior orientation is to calculate the elements of image forming moment by using fundamental ground control points. Utilizing satellite raw data file directly, which holds abundant information and using the numerical analysis methods of modern mathematics, the parameter equations about each element of exterior orientation are adjused and the elements of image forming moment under some precision are calculated. 展开更多
关键词 ELEMENTS of exterior ORIENTATION ground control point numerical analysis parameter equation
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Exteriorized colon anastomosis for unprepared bowel: An alternative to routine colostomy
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作者 Sami K Asfar Hilal M Al-Sayer Talib H Juma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第23期3215-3220,共6页
AIM: To see the possibility of avoiding routine colostomy in patients presenting with unprepared bowel. METHODS: The cohort is composed of 103 patients, of these, 86 patients presented as emergencies (self- inflected ... AIM: To see the possibility of avoiding routine colostomy in patients presenting with unprepared bowel. METHODS: The cohort is composed of 103 patients, of these, 86 patients presented as emergencies (self- inflected and iatrogenic colon injuries, stab wounds and blast injury of the colon, volvulus sigmoid, obstructing left colon cancer, and strangulated ventral hernia). Another 17 patients were managed electively for other colon pathologies. During laparotomy, the involved segment was resected and the two ends of the colon were brought out via a separate colostomy wound. One layer of interrupted 3/0 silk was used for colon anastomosis. The exteriorized segment was immediately covered with a colostomy bag. Between the 5th and 7th postoperative day, the colon was easily dropped into the peritoneal cavity. The defect in the abdominal wall was closed with interrupted nonabsorbable suture. The skin was left open for secondary closure. RESULTS: The mean hospital stay (± SD) was 11.5 ± 2.6 d (8-20 d). The exteriorized colon was successfully dropped back into the peritoneal cavity in all patients except two. One developed a leak from oesophago- jejunostomy and from the exteriorized colon. She subsequently died of sepsis and multiple organ failure (MOF). In a second patient the colon proximal to the exteriorized anastomosis prolapsed and developed severe serositis, an elective ileo-colic anastomosis (to the left colon) was successfully performed. CONCLUSION: Exteriorized colon anastomosis is simple, avoids the inconvenience of colostomy and can be an alternative to routine colostomy. It is suitable where colostomy is socially unacceptable or the facilities and care is not available. 展开更多
关键词 COLOSTOMY exteriorized colon Colon injury Colon anastomosis Unprepared colon Obstructing colon cancer Volvulus sigmoid
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THE SINGULAR LIMIT OF SECOND-GRADE FLUID EQUATIONS IN A 2D EXTERIOR DOMAIN
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作者 游小光 臧爱彬 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1333-1346,共14页
In this paper, we consider the second-grade fluid equations in a 2D exterior domain satisfying the non-slip boundary conditions. The second-grade fluid model is a wellknown non-Newtonian fluid model, with two paramete... In this paper, we consider the second-grade fluid equations in a 2D exterior domain satisfying the non-slip boundary conditions. The second-grade fluid model is a wellknown non-Newtonian fluid model, with two parameters: α, which represents the length-scale,while ν > 0 corresponds to the viscosity. We prove that, as ν, α tend to zero, the solution of the second-grade fluid equations with suitable initial data converges to the one of Euler equations, provided that ν = o(α^(4/3)). Moreover, the convergent rate is obtained. 展开更多
关键词 second-grade fluid equations Euler equations exterior domain singular limit
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LOW MACH NUMBER LIMIT ON EXTERIOR DOMAINS
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作者 Donatella Donatelli Pierangelo Marcati 《Acta Mathematica Scientia》 SCIE CSCD 2012年第1期164-176,共13页
This paper is concerned with the low Mach number limit for the compressible Navier-Stokes equations in an exterior domain. We present here an approach based on Strichartz estimate defined on a non trapping exterior do... This paper is concerned with the low Mach number limit for the compressible Navier-Stokes equations in an exterior domain. We present here an approach based on Strichartz estimate defined on a non trapping exterior domain and we will be able to show the compactness and strong convergence of the velocity vector field. 展开更多
关键词 exterior domain compressible and incompressible Navier-Stokes equation low Mach number limit hyperbolic equations wave equations RESCALING dispersive estimates Strichartz estimates
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Finding vibrations of inclined cable structures by approximately solving governing equations for exterior matrix
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作者 W.PAULSEN M.MANNING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第11期1383-1402,共20页
In this paper, how to compute the eigenfrequencies of the structures composed of a series of inclined cables is shown. The physics of an inclined cable can be complicated, so solving the differential equations even ap... In this paper, how to compute the eigenfrequencies of the structures composed of a series of inclined cables is shown. The physics of an inclined cable can be complicated, so solving the differential equations even approximately is difficult. However, rather than solving the system of 4 first-order equations governing the dynamics of each cable, the governing equations are instead converted to a set of equations that the exterior matrix satisfies. Therefore, the exterior matrix method (EMM) is used without solving the original governing equations. Even though this produces a system of 6 first-order equations, the simple asymptotic techniques to find the first three terms of the perturbative solution can be used. The solutions can then be assembled to produce a 6 x 6 exterior matrix for a cable section. The matrices for each cable in the structure are multiplied together, along with the exterior matrices for each joint. The roots of the product give us the eigenfrequencies of the system. 展开更多
关键词 exterior matrix method (EMM) EIGENFREQUENCY inclined cable
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DISCRETENESS OF THE EXTERIOR TRANSMISSION EIGENVALUES
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作者 孙美满 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期110-124,共15页
In this paper we consider a kind of exterior transmission problem in which the refractive index n(x) is a piecewise positive constant. Through establishing an equivalent boundary integral system, we obtain that the ... In this paper we consider a kind of exterior transmission problem in which the refractive index n(x) is a piecewise positive constant. Through establishing an equivalent boundary integral system, we obtain that the set of exterior transmission eigenvalues is a discrete set. Furthermore, we prove that there does not exist a transmission eigenvalue under some conditions. 展开更多
关键词 exterior transmission eigenvalue inverse scattering problem Helmholtz equation
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Mixed spectral method for exterior problems of Navier-Stokes equations by using generalized Laguerre functions
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作者 焦裕建 郭本瑜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第5期561-574,共14页
In this paper, we investigate the mixed spectral method using generalized Laguerre functions for exterior problems of fourth order partial differential equations. A mixed spectral scheme is provided for the stream fun... In this paper, we investigate the mixed spectral method using generalized Laguerre functions for exterior problems of fourth order partial differential equations. A mixed spectral scheme is provided for the stream function form of the Navier-Stokes equations outside a disc. Numerical results demonstrate the spectral accuracy in space. 展开更多
关键词 spectral method exterior problems of fourth order Navier-Stokes equations
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GLOBAL EXISTENCE FOR THE NONHOMOGENEOUS QUASILINEAR WAVE EQUATION WITH A LOCALIZED WEAKLY NONLINEAR DISSIPATION IN EXTERIOR DOMAINS
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作者 Jeong Ja Bae 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1203-1215,共13页
It is proved that the global existence for the nonhomogeneous quasilinear wave equation with a localized weakly nonlinear dissipation in exterior domains.
关键词 quasilinear wave equation localized weakly nonlinear dissipation exterior domains
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