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On a-order-convexity of Fuzzy Syntopogenous Spaces
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作者 WANG Hong 《现代电子技术》 2007年第1期179-181,共3页
In this paper,we combine L-fuzzy syntopogenous structure on X with algebraic structure on X.First,the *-increasing and *-decreasing spaces have been studied.Second,we define a-order-convexity on syntopogenous structur... In this paper,we combine L-fuzzy syntopogenous structure on X with algebraic structure on X.First,the *-increasing and *-decreasing spaces have been studied.Second,we define a-order-convexity on syntopogenous structures(X,S,≤).some important properties of a-order-convexity have been obtained. 展开更多
关键词 模糊拓扑学 代数结构 一阶凸性 模糊拓扑空间
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Multiobjective Program with Support Functions Under(G, C, ρ)-Convexity Assumptions
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作者 YUAN Dehui LIU Xiaoling 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1148-1163,共16页
This paper deals with multiobjective programming problems with support functions under (G, C, ρ)-convexity assumptions. Not only sufficient but also necessary optimality conditions for this kind of multiobjective p... This paper deals with multiobjective programming problems with support functions under (G, C, ρ)-convexity assumptions. Not only sufficient but also necessary optimality conditions for this kind of multiobjective programming problems are established from a viewpoint of (G, C, ρ)-convexity. When the sufficient conditions are utilized, the corresponding duality theorems are derived for general Mond-Weir type dual program. 展开更多
关键词 (G C ρ)-convex G-duality theory G-necessary conditions G-sufficient conditions mul-tiobjective program
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无线传感器网络基于凸规划的改进定位算法:Convex-PIT 被引量:14
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作者 张翰 刘锋 《传感技术学报》 CAS CSCD 北大核心 2007年第5期1129-1133,共5页
定位技术是无线传感器网络的关键技术之一,为了提高无线传感器网络的定位精度,在Convex算法基础上提出了Convex-PIT算法.Convex-PIT算法通过引入锚节点构成的三角形进一步滤掉节点不可能存在的区域,缩小节点可能存在范围,提高定位精度.C... 定位技术是无线传感器网络的关键技术之一,为了提高无线传感器网络的定位精度,在Convex算法基础上提出了Convex-PIT算法.Convex-PIT算法通过引入锚节点构成的三角形进一步滤掉节点不可能存在的区域,缩小节点可能存在范围,提高定位精度.Convex-PIT算法增加了判断未知节点是否在锚节点组成的三角形内的计算量,但不需要增加节点的硬件条件和额外的功能.仿真结果表明,和Convex算法相比,Convex-PIT可以明显的提高定位精度,在锚节点的比例从10%增加到30%的过程中,定位精度提高幅度平均约15%. 展开更多
关键词 无线传感器网络 定位convex质心
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ECMWF参考大气谱模式在Convex320机上的发展 被引量:2
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作者 陈嘉滨 舒静君 陈雄山 《高原气象》 CSCD 北大核心 1996年第4期490-495,共6页
将ECMWF预报模式移植到Convex320机上,修改了I/O结构,使得该模式在该机上顺利运行。在模式中引入了参考大气,计算了6个实例,取得了较好的结果。另外,在该模式上还试验了CXS格式,节省了计算时间。
关键词 谱模式 参考大气 convex320机
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一种多跳Convex和APIT的改进定位:HCAPIT 被引量:4
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作者 李伟群 廖鹰 +1 位作者 齐欢 袁帅 《计算机工程与应用》 CSCD 2012年第5期63-65,共3页
针对定位算法中信标节点密度低带来的定位精度低以及定位覆盖率低的问题,提出一种基于多跳凸规划和PIT的定位算法HCAPIT。该算法利用未知节点的K跳邻居信标节点信息,采用最佳三角形内点测试法PIT估计未知节点可能存在区域,通过多跳Conve... 针对定位算法中信标节点密度低带来的定位精度低以及定位覆盖率低的问题,提出一种基于多跳凸规划和PIT的定位算法HCAPIT。该算法利用未知节点的K跳邻居信标节点信息,采用最佳三角形内点测试法PIT估计未知节点可能存在区域,通过多跳Convex对区域缩小,对节点进行定位。仿真结果表明改进的定位算法更适合信标节点密度低的网络。 展开更多
关键词 无线传感器网络 定位 凸规划 近似三角形内点测试法(APIT)
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无线传感器网络一种改进的convex定位算法 被引量:3
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作者 范磊 刘锋 《无线电通信技术》 2007年第1期52-55,共4页
以convex(凸规划)定位算法为基础,针对range-free定位算法中anchor(已知节点)比例低带来的定位精度低、网络覆盖率低的问题,提出了二跳信息改进定位算法。该算法中,未知节点在通信中加入自身邻居anchor的ID和位置信息并发送给邻居节点,... 以convex(凸规划)定位算法为基础,针对range-free定位算法中anchor(已知节点)比例低带来的定位精度低、网络覆盖率低的问题,提出了二跳信息改进定位算法。该算法中,未知节点在通信中加入自身邻居anchor的ID和位置信息并发送给邻居节点,相应的邻居节点从中确定自己的二跳邻居anchor,并利用二跳邻居anchor的二跳通信范围来减小未知节点的可能存在区域,进而提高未知节点的定位精度。仿真表明,二跳信息改进定位算法在anchor节点比例较低情况下能有效提高定位精度,而在anchor节点比例较高时接近原convex算法定位精度,并且网络规模越大这种提高越显著。 展开更多
关键词 range—free定位算法 无线传感器网络 convex
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:3
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作者 丁协平 《应用数学和力学》 EI CSCD 北大核心 2004年第6期563-571,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 集值映象组 非空交定理 广义矢量平衡问题组 乘积G凸空间
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Fuzzy entropy design for non convex fuzzy set and application to mutual information 被引量:7
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作者 LEE Sang-Hyuk LEE Sang-Min +1 位作者 SOHN Gyo-Yong KIM Jaeh-Yung 《Journal of Central South University》 SCIE EI CAS 2011年第1期184-189,共6页
Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance measure.The proposed fuzzy entropy had the same structure as that of convex fuzzy membership case.Design procedure ... Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance measure.The proposed fuzzy entropy had the same structure as that of convex fuzzy membership case.Design procedure of fuzzy entropy was proposed by considering fuzzy membership through distance measure,and the obtained results contained more flexibility than the general fuzzy membership function.Furthermore,characteristic analyses for non convex function were also illustrated.Analyses on the mutual information were carried out through the proposed fuzzy entropy and similarity measure,which was also dual structure of fuzzy entropy.By the illustrative example,mutual information was discussed. 展开更多
关键词 fuzzy entropy non convex fuzzy membership function distance measure similarity measure mutual information
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Inertial projection algorithms for convex feasibility problem 被引量:2
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作者 Yazheng Dang Yan Gao Lihua Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期734-740,共7页
The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility... The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility problem.Compared with the existing accelerated methods for solving the problem,the inertial technique employs a parameter sequence and two previous iterations to get the next iteration and hence improves the flexibility of the algorithm.Theoretical asymptotic convergence results are presented under some suitable conditions.Numerical simulations illustrate that the new methods have better convergence than the general projection methods.The presented algorithms are inspired by the inertial proximal point algorithm for finding zeros of a maximal monotone operator. 展开更多
关键词 convex feasibility problem inertial technique string averaging block iteration asymptotic convergence
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Global convergent algorithm for the bilevel linear fractional-linear programming based on modified convex simplex method 被引量:2
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作者 Guangmin Wang Bing Jiang +1 位作者 Kejun Zhu Zhongping Wan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期239-243,共5页
A global convergent algorithm is proposed to solve bilevel linear fractional-linear programming, which is a special class of bilevel programming. In our algorithm, replacing the lower level problem by its dual gap equ... A global convergent algorithm is proposed to solve bilevel linear fractional-linear programming, which is a special class of bilevel programming. In our algorithm, replacing the lower level problem by its dual gap equaling to zero, the bilevel linear fractional-linear programming is transformed into a traditional sin- gle level programming problem, which can be transformed into a series of linear fractional programming problem. Thus, the modi- fied convex simplex method is used to solve the infinite linear fractional programming to obtain the global convergent solution of the original bilevel linear fractional-linear programming. Finally, an example demonstrates the feasibility of the proposed algorithm. 展开更多
关键词 bilevel linear fractional-linear programming convex simplex method dual problem.
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A novel method for virtual clearance computation of high-speed train based on model integration and convex hull 被引量:1
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作者 YI Bing LI Xiong-bing +2 位作者 ZENG Wei SONG Yong-feng YANG Yue 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2458-2467,共10页
The 3D clearance of a high-speed train(HST) is critical to ensure the safety of railway transportation. Many studies have been conducted on the inspection of the clearance profile in railway operation based on the vis... The 3D clearance of a high-speed train(HST) is critical to ensure the safety of railway transportation. Many studies have been conducted on the inspection of the clearance profile in railway operation based on the vision system, but few researchers have focused on the computation of the 3D clearance in the design phase of an HST. This paper summarizes the virtual 3D clearance computation of an HST based on model integration and the convex hull method. First, both the aerodynamic and kinetic analysis models of the HST are constructed. The two models are then integrated according to the corresponding relationship map, and an array of transformation matrixes of the HST is created to drive the designed model simulating the physical railway motion. Furthermore, the convex hull method is adopted to compute the 3D envelope of the moving train. Finally, the Hausdorff metric is involved in the measurement of the minimum clearance model and the 3D envelope model. In addition, the color map of the Hausdorff distance is established to verify that the designed shape of the HST meets the national standards. This paper provides an effective method to accurately calculate the 3D clearance for the shape design of an HST, which greatly reduces the development cost by minimizing the physical prototype that must be built. 展开更多
关键词 high-speed TRAIN 3D CLEARANCE convex HULL model integration HAUSDORFF distance
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Multiconstraint adaptive three-dimensional guidance law using convex optimization 被引量:6
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作者 FU Shengnan LIU Xiaodong +1 位作者 ZHANG Wenjie XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期791-803,共13页
The traditional guidance law only guarantees the accuracy of attacking a target. However, the look angle and acceleration constraints are indispensable in applications. A new adaptive three-dimensional proportional na... The traditional guidance law only guarantees the accuracy of attacking a target. However, the look angle and acceleration constraints are indispensable in applications. A new adaptive three-dimensional proportional navigation(PN) guidance law is proposed based on convex optimization. Decomposition of the three-dimensional space is carried out to establish threedimensional kinematic engagements. The constraints and the performance index are disposed by using the convex optimization method. PN guidance gains can be obtained by solving the optimization problem. This solution is more rapid and programmatic than the traditional method and provides a foundation for future online guidance methods, which is of great value for engineering applications. 展开更多
关键词 proportional navigation(PN) adaptive guidance law three-dimensional space second-order cone programming(SOCP) convex optimal control
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Approximate subgradient projection algorithm for convex feasibility problem 被引量:1
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作者 Li Li Yan Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期527-530,共4页
An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is est... An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is established.Moreover,compared with the existing projection hyperplanes methods with subgradient,the proposed hyperplanes are interactive with ε,and their ranges are more larger.The convergence of the proposed algorithm is given under some mild conditions,and the validity of the algorithm is proved by the numerical test. 展开更多
关键词 ε-subgradient projection algorithm convex feasibility problem.
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Convex Optimization Algorithms for Cooperative Localization in Autonomous Underwater Vehicles 被引量:9
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作者 LIU Ming-Yong LI Wen-Bai PEI Xuan 《自动化学报》 EI CSCD 北大核心 2010年第5期704-710,共7页
关键词 最优化 自动化系统 自适应系统 AUV
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Stabilization of linear time-varying systems with state and input constraints using convex optimization 被引量:1
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作者 Feng Tan Mingzhe Hou Guangren Duan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期649-655,共7页
The stabilization problem of linear time-varying systems with both state and input constraints is considered. Sufficient conditions for the existence of the solution to this problem are derived and a gain-switched(ga... The stabilization problem of linear time-varying systems with both state and input constraints is considered. Sufficient conditions for the existence of the solution to this problem are derived and a gain-switched(gain-scheduled) state feedback control scheme is built to stabilize the constrained timevarying system. The design problem is transformed to a series of convex feasibility problems which can be solved efficiently. A design example is given to illustrate the effect of the proposed algorithm. 展开更多
关键词 linear time-varying stabilization state constraints convex optimization
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Predictor-corrector interior-point algorithm for linearly constrained convex programming
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作者 LIANG Xi-ming (College of Information Science & Engineering, Central South University, Changsh a 410083, China) 《Journal of Central South University》 SCIE EI CAS 2001年第3期208-212,共5页
Active set method and gradient projection method are curre nt ly the main approaches for linearly constrained convex programming. Interior-po int method is one of the most effective choices for linear programming. In ... Active set method and gradient projection method are curre nt ly the main approaches for linearly constrained convex programming. Interior-po int method is one of the most effective choices for linear programming. In the p aper a predictor-corrector interior-point algorithm for linearly constrained c onvex programming under the predictor-corrector motivation was proposed. In eac h iteration, the algorithm first performs a predictor-step to reduce the dualit y gap and then a corrector-step to keep the points close to the central traject ory. Computations in the algorithm only require that the initial iterate be nonn egative while feasibility or strict feasibility is not required. It is proved th at the algorithm is equivalent to a level-1 perturbed composite Newton method. Numerical experiments on twenty-six standard test problems are made. The result s show that the proposed algorithm is stable and robust. 展开更多
关键词 linearly constrained convex programming PREDICTOR corrector interior point algorithm numerical experiment
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机器设计选择、工程平衡及Convex C2系列的决策过程
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作者 沈雁 金士尧 《计算机工程与科学》 CSCD 1989年第4期1-6,共6页
计算机界普遍认为,计算机结构还没有形成一种科学,只是一种工艺,至多在某些部分可称为科学,大部分只是一种科学的方法。从广义上讲计算机重要的不是发明什么,而是要形成一种别人肯买它的产品。买的人越多,应用就越广;应用越广,它本身的... 计算机界普遍认为,计算机结构还没有形成一种科学,只是一种工艺,至多在某些部分可称为科学,大部分只是一种科学的方法。从广义上讲计算机重要的不是发明什么,而是要形成一种别人肯买它的产品。买的人越多,应用就越广;应用越广,它本身的改进也就越快。在开始设计一种新机器时,必须要考虑到预算,元器件的现状水平,需要消耗多少人年,技术的提前量与实际实施的可能性等综合因素,在诸多因素中力求取得最佳平衡点。由于我们只考虑机器本身,故在此不考虑市场前景等非技术性的因素。 展开更多
关键词 机器设计 决策过程 convex C2 现状水平 非技术性 计算机结构 计算机界 并行处理 计算机市场 结构效率
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基于非凸稀疏与低秩分解的车载雷达抗干扰方法 被引量:1
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作者 李家强 危雨萱 +1 位作者 任梦豪 陈金立 《现代雷达》 北大核心 2025年第2期58-65,共8页
车载及道路设备毫米波雷达的广泛应用,使得雷达之间的相互干扰引起了诸多交通安全隐患。为此,文中提出了一种基于非凸正则化稀疏和低秩分解的信号分离方法来抑制雷达间的相互干扰。首先,利用雷达回波信号中目标分量和干扰分量的低秩和... 车载及道路设备毫米波雷达的广泛应用,使得雷达之间的相互干扰引起了诸多交通安全隐患。为此,文中提出了一种基于非凸正则化稀疏和低秩分解的信号分离方法来抑制雷达间的相互干扰。首先,利用雷达回波信号中目标分量和干扰分量的低秩和稀疏特性构建优化模型,将干扰抑制问题转化为了优化问题;然后,在使用极大极小非凸稀疏惩罚作为稀疏惩罚的情况下,借助交替方向乘子法进行迭代优化;最后,在指定误差范围内结束迭代,分别求解出目标分量和干扰分量,实现了有用信号和干扰信号的精准分离。与现有的信号处理方法相比,所提方法跳过了繁琐的干扰检测步骤,且干扰抑制后的信号与纯净参考信号的相关系数达到了0.9997。仿真模拟以及后续的实验结果表明该方法对雷达间干扰的抑制具有优异的性能。 展开更多
关键词 毫米波雷达 干扰抑制 低秩 稀疏 极大极小非凸稀疏惩罚
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滚子凸度对数曲线工程化设计的几点探讨
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作者 孙东 罗天宇 +2 位作者 高作斌 韩珂珂 李超强 《轴承》 北大核心 2025年第5期8-13,共6页
在面向工程应用的滚子凸度对数曲线设计方面,国内各相关企业认识并不统一,一定程度上影响了产品的工况适应性和市场竞争力。针对滚子凸度对数曲线设计中设计载荷不统一,滚子有效接触长度选取存在人为干预以及缺乏凸度偏差设计等问题,提... 在面向工程应用的滚子凸度对数曲线设计方面,国内各相关企业认识并不统一,一定程度上影响了产品的工况适应性和市场竞争力。针对滚子凸度对数曲线设计中设计载荷不统一,滚子有效接触长度选取存在人为干预以及缺乏凸度偏差设计等问题,提出了设计载荷按重载荷等级计算,载荷等级系数统一取0.3,推导出了考虑实际压缩变形的滚子有效接触长度表达式,并通过分析凸度值变化对滚子接触应力的影响,给出了对数曲线偏差设计方法,得到了凸度上下偏差对数曲线方程。 展开更多
关键词 滚动轴承 滚子 凸度 对数 载荷 偏差 接触应力
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内置式纺锤形滚柱套管塑性整形工具设计及应用分析
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作者 李明飞 王乐康 +5 位作者 宋显民 曹欣 米红学 张文哲 景志明 崔健 《塑性工程学报》 北大核心 2025年第7期135-143,共9页
设计了一套内置式纺锤形滚柱套管整形工具,其采用纺锤形滚柱代替滚珠,用均匀面接触代替非均匀点接触,使整形段套管发生塑性变形,可以完全消除凸痕的致命缺陷;通过内外管结合通槽结构实现滚柱内置,克服了套管整形工具滚珠掉落的缺陷;通... 设计了一套内置式纺锤形滚柱套管整形工具,其采用纺锤形滚柱代替滚珠,用均匀面接触代替非均匀点接触,使整形段套管发生塑性变形,可以完全消除凸痕的致命缺陷;通过内外管结合通槽结构实现滚柱内置,克服了套管整形工具滚珠掉落的缺陷;通过滚珠行程槽内置深度的改变,上提整形工具时,纺锤形滚柱缩回到滚柱安装通槽内,避免对整形后套管形成剐蹭的二次伤害。设计的整形工具还具有易加工、易安装的优点。应用ANSYS软件,建立了完整的内置式纺锤形滚柱套管整形工具有限元模型,施加套管整形典型工况下的载荷,分析了中心管轴肩抗压、连接螺纹抗拉的强度,安全系数均在3.0以上,满足强度要求。同时,建立整形工具与缩径变形、椭圆变形、弯曲变形、局部凹陷4种常见套管变形配合整形的仿真模型,用ABAQUS动力学显式模块,仿真分析整形过程,结果表明,整形工具各部件无塑性变形、可重复使用、滚柱未掉落;整形后的套管通径达标、无凸痕、上提无伤害,整形效果理想。该整形工具在大庆油田的宁8井、岔81井、华北油田的强2-4X井等30多口井投入使用,整形效果显著,克服了现有整形工具的缺陷,具有很好的实用性。 展开更多
关键词 套管整形 整形工具 纺锤形滚柱 凸痕处理 防止掉落
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