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Petrophysical Evaluation of Cape Three Points Reservoirs
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作者 Striggner Bedu-Addo Sylvester Kojo Danuor Larry Pax Chegbeleh 《International Journal of Geosciences》 CAS 2024年第2期162-179,共18页
The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and T... The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and Techlog. The investigated characteristics, which were all deduced from geophysical wire-line logs, include lithology, porosity, permeability, fluid saturation, and net to gross thickness. To characterise the reservoir on the field, a suite of wire-line logs including gamma ray, resistivity, spontaneous potential, and density logs for three wells (WELL_1X, WELL_2X, and WELL_3X) from the Tano Cape Three Point basin were studied. The analyses that were done included lithology delineation, reservoir identification, and petrophysical parameter determination for the identified reservoirs. The tops and bases of the three wells analysed were marked at a depth of 1203.06 - 2015.64 m, 3863.03 - 4253.85 m and 2497.38 - 2560.32 m respectively. There were no hydrocarbons in the reservoirs from the studies. The petrophysical parameters computed for each reservoir provided porosities of 13%, 3% and 11% respectively. The water saturation also determined for these three wells (WELL_1X, WELL_2X and WELL_3X) were 94%, 95% and 89% respectively. These results together with the behaviour of the density and neutron logs suggested that these wells are wildcat wells. 展开更多
关键词 Petrophysical Cape three points RESERVOIRS
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THREE POINT BOUNDARY VALUE PROBLEMS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS 被引量:1
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作者 Mujeeb ur Rehman Rahmat Ali Khan Naseer Ahmad Asif 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1337-1346,共10页
In this paper, we study existence and uniqueness of solutions to nonlinear three point boundary value problems for fractional differential equation of the type c D δ 0+ u(t) = f (t, u(t), c D σ 0+ u(t)), t... In this paper, we study existence and uniqueness of solutions to nonlinear three point boundary value problems for fractional differential equation of the type c D δ 0+ u(t) = f (t, u(t), c D σ 0+ u(t)), t ∈ [0, T ], u(0) = αu(η), u(T ) = βu(η), where 1 〈 δ 〈 2, 0 〈 σ 〈 1, α, β∈ R, η∈ (0, T ), αη(1 -β) + (1-α)(T βη) = 0 and c D δ 0+ , c D σ 0+ are the Caputo fractional derivatives. We use Schauder fixed point theorem and contraction mapping principle to obtain existence and uniqueness results. Examples are also included to show the applicability of our results. 展开更多
关键词 fractional differential equations three point boundary conditions existence and uniqueness results
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Existence of Multiple Positive Solutions on the Three Point Boundary Value Problems 被引量:1
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作者 任立顺 王治国 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期406-411,共6页
In this paper, using fixed theorem in cones, the authors obtain the existence of multiple positive solutions on the following boundary value problem u"+a(t)f(u)=0,t∈[0,1],u(0)=0,au(η)^*=u(1).
关键词 second order three point BUP positive solution cone EXISTENCE
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“Three Methods and Three Points” regulates p38 mitogen-activated protein kinase in the dorsal horn of the spinal cord in a rat model of sciatic nerve injury 被引量:8
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作者 Xin Guo Tian-yuan Yu +8 位作者 Wong Steven Wen-duan Jia Chi Ma Yan-hong Tao Chao Yang Tao-tao Lv Shuai Wu Meng-qian Lu Jia-li Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第12期2018-2024,共7页
Tuina is a traditional Chinese treatment for sensory disturbances caused by peripheral nerve injury and related diseases. Our previous studies showed that tuina regulates relevant regions and indices of the spinal dor... Tuina is a traditional Chinese treatment for sensory disturbances caused by peripheral nerve injury and related diseases. Our previous studies showed that tuina regulates relevant regions and indices of the spinal dorsal horn using the Dian, Bo, and Rou method in Yinmen(BL37), Yanglingquan(GB34), and Weizhong(BL40). Treatment prevents muscle atrophy, protects spinal cord neurons, and promotes sciatic nerve repair. The mechanisms of action of tuina for treating peripheral nerve injury remain poorly understood. This study established rat models of sciatic nerve injury using the crushing method. Rats received Chinese tuina in accordance with the principle of "Three Methods and Three Points," once daily for 20 days. Tuina intervention reduced paw withdrawal latency and improved wet weight of the gastrocnemius muscle, as well as promoting morphological recovery of sciatic nerve fibers, Schwann cells, and axons. The protein expression levels of phospho-p38 mitogen-activated protein kinase, tumor necrosis factor-α, and interleukin-1β also decreased. These findings indicate that "Three Methods and Three Points" promoted morphological recovery and improved behavior of rats with peripheral nerve injury. 展开更多
关键词 nerve regeneration tuina three Methods and three points phospho-p38 mitogen-activated protein kinase sciatic nerve injury tumor necrosis factor-α interleukin-1β dorsal horn of the spinal cord neural regeneration
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order three-point Boundary Value Problem Sign-Changing Green’s Function Fixed point Index Iterative Technique Monotone Positive Solution EXISTENCE
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Three-point bending of honeycomb sandwich beams with facesheet perforations 被引量:3
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作者 Pengbo Su Bin Han +2 位作者 Zhongnan Zhao Qiancheng Zhang Tian Jian Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第4期667-675,共9页
A novel square honeycomb-cored sandwich beam with perforated bottom facesheet is investigated under threepoint bending,both analytically and numerically.Perforated square holes in the bottom facesheet are characterize... A novel square honeycomb-cored sandwich beam with perforated bottom facesheet is investigated under threepoint bending,both analytically and numerically.Perforated square holes in the bottom facesheet are characterized by the area ratio of the hole to intact facesheet(perforation ratio).While for large-scale engineering applications like the decks of cargo vehicles and transportation ships,the perforations are needed to facilitate the fabrication process(e.g.,laser welding)as well as service maintenance,it is demonstrated that these perforations,when properly designed,can also enhance the resistance of the sandwich to bending.For illustration,fair comparisons among competing sandwich designs having different perforation ratios but equal mass is achieved by systematically thickening the core webs.Further,the perforated sandwich beam is designed with a relatively thick facesheet to avoid local indention failure so that it mainly fails in two competing modes:(1)bending failure,i.e.,yielding of beam cross-section and buckling of top facesheet caused by bending moment;(2)shear failure,i.e.,yielding and buckling of core webs due to shear forcing.The sensitivity of the failure loads to the ratio of core height to beam span is also discussed for varying perforation ratios.As the perfo-ration ratio is increased,the load of shear failure increases due to thickening core webs,while that of bending failure decreases due to the weakening bottom facesheet.Design of a sandwich beam with optimal perforation ratio is realized when the two failure loads are equal,leading to significantly enhanced failure load(up to 60%increase)relative to that of a non-perforated sandwich beam with equal mass. 展开更多
关键词 Honeycomb sandwich Facesheet perforation three-point bending Analytical model
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TWO POSITIVE SOLUTIONS TO THREE-POINT SINGULAR BOUNDARY VALUE PROBLEMS 被引量:3
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作者 李宇华 梁占平 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期29-38,共10页
In this article, we consider the existence of two positive solutions to nonlinear second order three-point singular boundary value problem: -u′′(t) = λf(t, u(t)) for all t ∈ (0, 1) subjecting to u(0) = ... In this article, we consider the existence of two positive solutions to nonlinear second order three-point singular boundary value problem: -u′′(t) = λf(t, u(t)) for all t ∈ (0, 1) subjecting to u(0) = 0 and αu(η) = u(1), where η ∈ (0, 1), α ∈ [0, 1), and λ is a positive parameter. The nonlinear term f(t, u) is nonnegative, and may be singular at t = 0, t = 1, and u = 0. By the fixed point index theory and approximation method, we establish that there exists λ* ∈ (0, +∞], such that the above problem has at least two positive solutions for any λ ∈ (0, λ*) under certain conditions on the nonlinear term f. 展开更多
关键词 three-point singular boundary value problem positive solutions fixed point index
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Dynamic Fracture Behaviors of Selected Aluminum Alloys Under Three-point Bending 被引量:2
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作者 Ming-zhi XING Yong-gang WANG Zhao-xiu JIANG 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第4期193-200,共8页
The dynamic fracture behaviors of the extruded 2024-T4 and 7075-T6 aluminum alloys are investigated by using an instrumented drop tower machine.The specimens are made from a 25 mm diameter extruded circular rod.The dy... The dynamic fracture behaviors of the extruded 2024-T4 and 7075-T6 aluminum alloys are investigated by using an instrumented drop tower machine.The specimens are made from a 25 mm diameter extruded circular rod.The dynamic three-point bending tests of each alloy are carried out at different impact velocities.The initiation fracture toughness and average propagation fracture toughness of 2024-T4 and 7075-T6 are determined at different loading rates.The results show that both the initiation toughness and the propagation toughness increase with the loading rate.Further,the difference between the fracture toughness behaviors of 2024-T4 and 7075-T6 is found to be dependent on the variation of fracture mechanism.The comprehensive fractographic investigations of the fracture surfaces clearly demonstrate that the fracture mode of 2024-T4 is predominantly transgranular fracture with high density small-sized dimples,and the fracture mode of 7075-T6 is mainly intergranular fracture with many intermetallic particles in the bottom of voids located in the fracture surface. 展开更多
关键词 动态断裂行为 三点弯曲试验 铝合金 行为研究 断裂韧性 加载速率 断裂模式 IRMA
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Existence of Sign-changing Solution for Three-point Boundary Value Problems 被引量:4
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作者 LI Chun-yan SU Ya-juan 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期458-466,共9页
In this paper, by using the fixed-point index theory, we study the existence of sign-changing solution of some three-point boundary value problems {y ''(t) + f(y) = 0, t ∈ [0, 1], y' (0) = 0, y(1) = αy(... In this paper, by using the fixed-point index theory, we study the existence of sign-changing solution of some three-point boundary value problems {y ''(t) + f(y) = 0, t ∈ [0, 1], y' (0) = 0, y(1) = αy(η), where 0 < α < 1, 0 < η < 1, f : R → R is continuous, strictly increasing and f(0) = 0. 展开更多
关键词 three-point boundary value problem sign-changing solution the fixed-point index theory
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A CATASTROPHE ANALYSIS ON THE STABILITY OF THE CRACK GROWTH IN THREE-POINT BENDING SPECIMENS 被引量:2
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作者 Wei Demin Fan Xuejun, Taiyuan Unversity of Technology, Taiyuan 030024 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第2期179-183,共5页
This paper presents an attempt at the application of catastrophe theory to the stability analysis of J-controlled crack growth in three-point bending specimens. By introducing the solutions of J-integral in the comple... This paper presents an attempt at the application of catastrophe theory to the stability analysis of J-controlled crack growth in three-point bending specimens. By introducing the solutions of J-integral in the completely yielding state for the ideal plastic material, the critical condition of losing stability for the crack propagation in the specimen is obtained, based on the cusp catastrophe theory. The process of the crack growth from geometrical sense is described. 展开更多
关键词 crack growth STABILITY cusp catastrophe J-INTEGRAL three-point bending specimen
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On the Existence of Positive Solution for a Nonlinear Third-order Three-point Boundary Value Problem 被引量:6
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作者 姚庆六 《Northeastern Mathematical Journal》 CSCD 2003年第3期244-248,共5页
An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, ... An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, and is not asymptotic at zero and infinity. 展开更多
关键词 third-order ordinary differential equation three-point boundary value problem positive solution EXISTENCE
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NONTRIVIAL SOLUTION OF A NONLINEAR SECOND-ORDER THREE-POINT BOUNDARY VALUE PROBLEM 被引量:2
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作者 Li Shuhong Sun Yongping Department of Mathematics, Lishui University, Lishui 323000,China Department of Applied Mathematics, Zhejiang Sci-Tec University, Hangzhou 310018, China Department of Electron and Information, Zhejiang University of Media and Communications, Hangzhou 310018, China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第1期37-47,共11页
In this paper, for a second-order three-point boundary value problem u″+f(t,u)=0,0〈t〈1,au(0)-bu′(0)=0,u(1)-au(η)=0,where η∈ (0, 1), a, b, α ∈R with a^2 + b^2 〉 0, the existence of its nontrivia... In this paper, for a second-order three-point boundary value problem u″+f(t,u)=0,0〈t〈1,au(0)-bu′(0)=0,u(1)-au(η)=0,where η∈ (0, 1), a, b, α ∈R with a^2 + b^2 〉 0, the existence of its nontrivial solution is studied. The'conditions on f which guarantee the existence of nontrivial solution are formulated. As an application, some examples to demonstrate the results are given. 展开更多
关键词 three-point boundary value problem nonlinear alternative of Leray-Schauder nontrivial solution.
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Existence of Positive Solutions of Three-point Boundary Value Problem for Higher Order Nonlinear Fractional Differential Equations 被引量:2
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作者 韩仁基 葛建生 蒋威 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期516-525,共10页
In this paper, we consider the positive solutions of fractional three-point boundary value problem of the form Dο^α+u(t)+f(t,u(t),u'(t),…,u^(n-3)(5),u^(n-2)(t))=0,u^(i)(0)=0,0≤i≤n-2,u^(n-... In this paper, we consider the positive solutions of fractional three-point boundary value problem of the form Dο^α+u(t)+f(t,u(t),u'(t),…,u^(n-3)(5),u^(n-2)(t))=0,u^(i)(0)=0,0≤i≤n-2,u^(n-2)(1)-βu^(n-2)(ξ)=0,where 0〈t〈1,n-1〈α≤n,n≥2,ξ Е(0,1),βξ^a-n〈1. We first transform it into another equivalent boundary value problem. Then, we derive the Green's function for the equivalent boundary value problem and show that it satisfies certain properties. At last, by using some fixed-point theorems, we obtain the existence of positive solution for this problem. Example is given to illustrate the effectiveness of our result. 展开更多
关键词 nonlinear fractional differential equation three-point boundary value problem positive solutions green’s function banach contraction mapping fixed point theorem in cones
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Triple Positive Solutions for a Third-order Three-point Boundary Value Problem 被引量:1
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作者 WU Hong-ping 《Chinese Quarterly Journal of Mathematics》 2019年第3期283-289,共7页
In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Pete... In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Peterson,we establish results of triple positive solutions to the boundary value problem,and an example is given to illustrate the importance of result obtained. 展开更多
关键词 THIRD-ORDER three-point boundary value problem POSITIVE solutions FIXED-point THEOREM
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Positive solutions of three-point boundary value problems 被引量:1
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作者 缪烨红 张吉慧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第6期817-823,共7页
In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in... In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in resonance cases. The proposed approach is based on the Krasnoselskii's fixed point theorem and the coincidence degree. 展开更多
关键词 three-point boundary value problems positive solution fixed point theorem coincidence degree theorem
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Existence of Multiple Positive Solutions for Third-Order Three-Point Boundary Value Problem 被引量:1
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作者 Qiufeng Chen Jianli Li 《Journal of Applied Mathematics and Physics》 2019年第7期1463-1472,共10页
In this paper, we study the existence of positive solutions for a class of third-order three-point boundary value problem. By employing the fixed point theorem on cone, some new criteria to ensure the three-point boun... In this paper, we study the existence of positive solutions for a class of third-order three-point boundary value problem. By employing the fixed point theorem on cone, some new criteria to ensure the three-point boundary value problem has at least three positive solutions are obtained. An example illustrating our main result is given. Moreover, some previous results will be improved significantly in our paper. 展开更多
关键词 THIRD-ORDER three-point BOUNDARY Value Problem Fixed point THEOREM three POSITIVE Solutions
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Triple Positive Solutions to a Third-order Three-point Boundary Value Problem with p-Laplacian Operator 被引量:1
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作者 谭惠轩 封汉颍 +1 位作者 冯杏芳 杜亚涛 《Chinese Quarterly Journal of Mathematics》 2015年第1期55-65,共11页
In this paper, we consider the three-point boundary value problem (φp(uˊˊ(t)))ˊ +a(t)f(t, u(t), uˊ(t), uˊˊ(t)) = 0, t ∈ [0, 1] subject to the boundary conditions u(0) =βuˊ(0), uˊ(1) =... In this paper, we consider the three-point boundary value problem (φp(uˊˊ(t)))ˊ +a(t)f(t, u(t), uˊ(t), uˊˊ(t)) = 0, t ∈ [0, 1] subject to the boundary conditions u(0) =βuˊ(0), uˊ(1) = αuˊ(η), uˊˊ(0) = 0, where φp(s) = |s|p?2s with p 〉 1, 0 〈 α, η 〈 1 and 0 ≤ β 〈 1. Applying a fixed point theorem due to Avery and Peterson, we study the existence of at least three positive solutions to the above boundary value problem. 展开更多
关键词 third-order three-point boundary value problem positive solution fixed point theorem
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Positive Solutions of a Second-Order Three-point Boundary Value Problem 被引量:1
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作者 李兆兴 张中新 《Northeastern Mathematical Journal》 CSCD 2002年第2期130-136,共7页
The existence of positive solutions is established for a nonlinear second-order three-point boundary value problem. The result improves and extends the main result in Electron J. Differential Equations, 34(1999), 1-8.
关键词 three-point boundary value problem positive solution EXISTENCE fixed point
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The Shengli I Point Bar on the Yellow River Delta: Three-Dimensional Structures and Their Evolution 被引量:1
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作者 钟建华 沈晓华 +8 位作者 倪晋仁 王冠民 温志峰 王夕宾 王海桥 李理 吴孔友 李勇 洪梅 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第4期463-477,共15页
Point bars are well developed on the Yellow River delta, an~ which theShengli I point bar is the most typical. The point bar, being about 4 km in length and several tensto more than 100 meters in width, is located on ... Point bars are well developed on the Yellow River delta, an~ which theShengli I point bar is the most typical. The point bar, being about 4 km in length and several tensto more than 100 meters in width, is located on the south side of the Shengli Bridge in KenliCounty, Dongying, Shandong. It is a typical fine-grained point bar with silt, which is predominant,some clay and minor plant debris and clay boulders. The Shengli I Point bar has complicated 3-Dstructures. Firstly, in a plane view, it comprises mainly eight sedimentary units, bar edge, baredge, bar platform, bar plain, bar channel, bar gully, bar pond and bar bay, developing side by sideand superimposed one by one m a complex way. Secondly, its vertical structures are very complex dueto the partial superimposition of the 8 sedimentary units. Besides hydatogenesis, very intensivewind erosion, eolian, ice and meltwater actions are also visible on the Shengli I point bar. Thecomplex form is made even more complicated because of the above co-actions. 展开更多
关键词 point bar three-dimensional structure EVOLUTION DELTA the Yellow River
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A New Algorithm of Roundness Error Separation Technique of Three-point Method
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作者 雷贤卿 李济顺 +3 位作者 薛玉君 马伟 崔凤奎 胡东方 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第2期141-145,共5页
Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, wh... Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, which can be used to solve directly the roundness of the measured round contour without Fourier transform, is presented. On the basis of the research and analysis of the rotation error movement which is separated by using the three-point method, a mathematical equation is derived, which can be used to separate the eccentric motion of least square center of measured round contour and the pure rotation motion error of spindle in rotation motion. The correctness of this method is validated by means of simulation. 展开更多
关键词 信息加工 三点方法 矩阵 偏心运动
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