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High Accuracy Network Cardinalities Estimation by Step Sampling Revision on GPU
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作者 Jie Xu Qun Wang +1 位作者 Yifan Wang Khan Asif 《Computers, Materials & Continua》 SCIE EI 2020年第9期1819-1844,共26页
Host cardinality estimation is an important research field in network management and network security.The host cardinality estimation algorithm based on the linear estimator array is a common method.Existing algorithm... Host cardinality estimation is an important research field in network management and network security.The host cardinality estimation algorithm based on the linear estimator array is a common method.Existing algorithms do not take memory footprint into account when selecting the number of estimators used by each host.This paper analyzes the relationship between memory occupancy and estimation accuracy and compares the effects of different parameters on algorithm accuracy.The cardinality estimating algorithm is a kind of random algorithm,and there is a deviation between the estimated results and the actual cardinalities.The deviation is affected by some systematical factors,such as the random parameters inherent in linear estimator and the random functions used to map a host to different linear estimators.These random factors cannot be reduced by merging multiple estimators,and existing algorithms cannot remove the deviation caused by such factors.In this paper,we regard the estimation deviation as a random variable and proposed a sampling method,recorded as the linear estimator array step sampling algorithm(L2S),to reduce the influence of the random deviation.L2S improves the accuracy of the estimated cardinalities by evaluating and remove the expected value of random deviation.The cardinality estimation algorithm based on the estimator array is a computationally intensive algorithm,which takes a lot of time when processing high-speed network data in a serial environment.To solve this problem,a method is proposed to port the cardinality estimating algorithm based on the estimator array to the Graphics Processing Unit(GPU).Experiments on real-world high-speed network traffic show that L2S can reduce the absolute bias by more than 22%on average,and the extra time is less than 61 milliseconds on average. 展开更多
关键词 Network security cardinality estimating parallel computing sampling revision
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Some Results on the Cardinalities of Row Space of Boolean Matrices
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作者 ZHONG Li-ping ZHOU Jian-hui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期582-588,共7页
Let Bn be the set of all n×n Boolean Matrices; R(A) denote the row space of A∈Bn, |R(A)| denote the cardinality of R(A), m, n, k, l, t, i, γi be positive integers, Si, λi be non negative integers. In t... Let Bn be the set of all n×n Boolean Matrices; R(A) denote the row space of A∈Bn, |R(A)| denote the cardinality of R(A), m, n, k, l, t, i, γi be positive integers, Si, λi be non negative integers. In this paper, we prove the following two results:(1)Let n≥13,n-3≥k〉Sl,Si+〉Si,i=1,2…,l-1.if k+l≤n,then for any m=2^k+2^S1-l+…+2^S1,there exists A∈Bn,such that |R(A)|=m.(2)Let n≥13,n-3≥k〉Sn-k-1〉Sn-k-2〉…S1〉λt〉λt-1〉…〉λ1,2≤t≤n-k.If exist γi(k+1≤γi≤n-1,i=1,2…,t-1)γi〈γi+1 and λt-λt-1≤k-Sn-γ1,λt-i-λt-i-1≤Sn-γi-Sn-γii+1,i=1,2…,t-2,then for any m=2^k+2^Sn-k-1+2^Sn-k-1+2^Sn-k-2+…+2^S1+2^λt+2^λt-1…+2^λ1,there exists A∈Bn,as such that |R(A)|=m. 展开更多
关键词 Boolean matrix row space cardinality of a row space
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Semi-quantum protocol for cardinalities of private set intersection and union based on GHZ states
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作者 Zhang Long Wang Weijian Zhang Kejia 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2022年第4期69-76,105,共9页
In modern society,it is necessary to perform some secure computations for private sets between different entities.For instance,two merchants desire to calculate the number of common customers and the total number of u... In modern society,it is necessary to perform some secure computations for private sets between different entities.For instance,two merchants desire to calculate the number of common customers and the total number of users without disclosing their own privacy.In order to solve the referred problem,a semi-quantum protocol for private computation of cardinalities of set based on Greenberger-Horne-Zeilinger(GHZ)states is proposed for the first time in this paper,where all the parties just perform single-particle measurement if necessary.With the assistance of semi-honest third party(TP),two semi-quantum participants can simultaneously obtain intersection cardinality and union cardinality.Furthermore,security analysis shows that the presented protocol can stand against some well-known quantum attacks,such as intercept measure resend attack,entangle measure attack.Compared with the existing quantum protocols of Private Set Intersection Cardinality(PSI-CA)and Private Set Union Cardinality(PSU-CA),the complicated oracle operations and powerful quantum capacities are not required in the proposed protocol.Therefore,it seems more appropriate to implement this protocol with current technology. 展开更多
关键词 quantum communication private set intersection cardinality private set union cardinality secure multiparty computation
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Scientific Elegance in NIDS: Unveiling Cardinality Reduction, Box-Cox Transformation, and ADASYN for Enhanced Intrusion Detection
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作者 Amerah Alabrah 《Computers, Materials & Continua》 SCIE EI 2024年第6期3897-3912,共16页
The emergence of digital networks and the wide adoption of information on internet platforms have given rise to threats against users’private information.Many intruders actively seek such private data either for sale... The emergence of digital networks and the wide adoption of information on internet platforms have given rise to threats against users’private information.Many intruders actively seek such private data either for sale or other inappropriate purposes.Similarly,national and international organizations have country-level and company-level private information that could be accessed by different network attacks.Therefore,the need for a Network Intruder Detection System(NIDS)becomes essential for protecting these networks and organizations.In the evolution of NIDS,Artificial Intelligence(AI)assisted tools and methods have been widely adopted to provide effective solutions.However,the development of NIDS still faces challenges at the dataset and machine learning levels,such as large deviations in numeric features,the presence of numerous irrelevant categorical features resulting in reduced cardinality,and class imbalance in multiclass-level data.To address these challenges and offer a unified solution to NIDS development,this study proposes a novel framework that preprocesses datasets and applies a box-cox transformation to linearly transform the numeric features and bring them into closer alignment.Cardinality reduction was applied to categorical features through the binning method.Subsequently,the class imbalance dataset was addressed using the adaptive synthetic sampling data generation method.Finally,the preprocessed,refined,and oversampled feature set was divided into training and test sets with an 80–20 ratio,and two experiments were conducted.In Experiment 1,the binary classification was executed using four machine learning classifiers,with the extra trees classifier achieving the highest accuracy of 97.23%and an AUC of 0.9961.In Experiment 2,multiclass classification was performed,and the extra trees classifier emerged as the most effective,achieving an accuracy of 81.27%and an AUC of 0.97.The results were evaluated based on training,testing,and total time,and a comparative analysis with state-of-the-art studies proved the robustness and significance of the applied methods in developing a timely and precision-efficient solution to NIDS. 展开更多
关键词 Adaptive synthetic sampling class imbalance features cardinality network security over sampling
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The Erdös-Faber-Lovász Conjecture for Gap-Restricted Hypergraphs
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作者 Zhimin Wang 《Engineering(科研)》 2024年第2期47-59,共13页
An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is ... An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is denoted by . Erdös, Faber and Lovász proposed a famous conjecture that  holds for any loopless linear hypergraph H with n vertices. In this paper, we show that  is true for gap-restricted hypergraphs. Our result extends a result of Alesandroni in 2021. 展开更多
关键词 Linear Hypergraph Chromatic Index Erdös-Faber-Lovász Conjecture Edge Cardinality
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基于Cardinal样条插值和三角面片的叶片静态建模 被引量:10
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作者 邓旭阳 周淑秋 +1 位作者 郭新宇 苑春颖 《计算机工程与应用》 CSCD 北大核心 2004年第25期199-200,204,共3页
提出了采用三角面片和Cardinal样条插值的方法对植物叶片静态建模的一种方法,该方法的优点是使用的型质点少,而生成的图形具有较强的真实感,具有实用价值。并给出了基于玉米叶片的建模结果。
关键词 Cardinal样务 角面片 片静态建模
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带形状因子的C^2连续五次Cardinal样条与Catmull-Rom样条 被引量:7
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作者 李军成 刘成志 易叶青 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2016年第11期1821-1831,共11页
针对三次Cardinal样条与Catmull-Rom样条的不足,提出带形状因子的C^2连续五次Cardinal样条与Catmull-Rom样条.首先构造一组带2个形状因子的五次Cardinal样条基函数;然后基于该组基函数定义带形状因子的五次Cardinal样条曲线与曲面,并讨... 针对三次Cardinal样条与Catmull-Rom样条的不足,提出带形状因子的C^2连续五次Cardinal样条与Catmull-Rom样条.首先构造一组带2个形状因子的五次Cardinal样条基函数;然后基于该组基函数定义带形状因子的五次Cardinal样条曲线与曲面,并讨论五次Cardinal样条函数的保单调插值;最后研究对应的一元与二元五次Catmull-Rom样条插值函数,并给出最优一元与二元五次Catmull-Rom样条插值函数的确定方法.实例结果表明,五次Cardinal样条与Catmull-Rom样条无需任何条件即可达到C^2连续,且其形状还可通过自带的形状因子进行灵活地调整,利用最优五次Catmull-Rom样条插值函数可获得满意的插值效果. 展开更多
关键词 Cardinal样条 CATMULL-ROM样条 插值样条 形状因子 C2连续
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Cardinal Numbers of Fuzzy Sets 被引量:8
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作者 李洪兴 罗承忠 +1 位作者 汪培庄 袁学海 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期101-107,共7页
Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable ... Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable as we point out in this paper. In the paper, we give a general definition of fuzzy cardinal numbers. Based on this definition, we not only obtain a large part of results with re spect to cardinal numbers, but also give a few of new properties of fuzzy cardinal numbers. 展开更多
关键词 Fuzzy relations Fuzzy mappings the cardinal numbers of fuzzy sets
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基于GPS和车辙的三维路面重构 被引量:8
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作者 马荣贵 汪花梅 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2012年第10期1517-1521,共5页
提出了一种基于地理定位系统(GPS)和横断面车辙数据的路面三维重构模型.针对GPS和车辙的采样间隔不同,首先采用Cardinal插值算法对非等间距的离散GPS点插值,并按间距需求选取等间距的插值点,然后将序列化后的GPS插值数据与车辙数据融合... 提出了一种基于地理定位系统(GPS)和横断面车辙数据的路面三维重构模型.针对GPS和车辙的采样间隔不同,首先采用Cardinal插值算法对非等间距的离散GPS点插值,并按间距需求选取等间距的插值点,然后将序列化后的GPS插值数据与车辙数据融合,构造出在三维空间中用于绘制三角形网格的顶点矩阵,最后实现了三维重构路面的绘制.实验表明用该方法重构的三维路面在路面车辙、坑槽及拥包的检测方面有很好的应用价值. 展开更多
关键词 道路工程 三维路面重构 Cardinal插值 车辙 理定位系统
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高斯混合粒子Cardinalized概率假设密度滤波被动测角多目标跟踪 被引量:5
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作者 张俊根 姬红兵 《控制理论与应用》 EI CAS CSCD 北大核心 2011年第1期46-52,共7页
为解决目标数未知或随时间变化的多目标跟踪问题,通常将多目标状态和观测数据表示为随机集形式,通过Cardinalized概率假设密度(CPHD)滤波,递推计算目标的强度(即概率假设密度,PHD)及目标数的概率分布.然而对于被动测角的非线性跟踪问题,... 为解决目标数未知或随时间变化的多目标跟踪问题,通常将多目标状态和观测数据表示为随机集形式,通过Cardinalized概率假设密度(CPHD)滤波,递推计算目标的强度(即概率假设密度,PHD)及目标数的概率分布.然而对于被动测角的非线性跟踪问题,CPHD无法获得闭合解.为此,本文提出一种新的高斯混合粒子CPHD算法,利用高斯混合近似PHD,避免了用聚类确定目标状态,同时,将拟蒙特卡罗(QMC)积分方法引入计算目标状态的预测和更新分布,取得了良好的效果. 展开更多
关键词 多目标跟踪 随机集 Cardinalized概率假设密度 被动测角 拟蒙特卡罗
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基于Cardinal的虚拟场景自动漫游算法 被引量:3
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作者 罗立宏 张群英 +1 位作者 冯开平 左宗义 《桂林工学院学报》 北大核心 2007年第2期278-281,共4页
对于虚拟场景自动漫游功能,存在改进的折线法和Hermite样条插值法,这两种方法都不能彻底消除漫游中摄像机抖动的现象.为了彻底克服抖动,提出以Cardinal样条插值算法为基础的新方法:先用Cardinal插值计算出足够密的曲线点,再根据这些点... 对于虚拟场景自动漫游功能,存在改进的折线法和Hermite样条插值法,这两种方法都不能彻底消除漫游中摄像机抖动的现象.为了彻底克服抖动,提出以Cardinal样条插值算法为基础的新方法:先用Cardinal插值计算出足够密的曲线点,再根据这些点在曲线上筛选等弧长的点,并用文件储存.在自动漫游的时候再根据等弧长的点和漫游速度切换摄像机.对于网络的应用,可用XML格式储存.基于Cardinal的方法可以彻底克服摄像机的抖动,使漫游曲线非常平滑.给出了一个Web应用的实例. 展开更多
关键词 虚拟现实 自动漫游 算法 Cardinal样条 插值
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Cardinal样条逼近 被引量:3
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作者 杨柱元 刘永平 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第5期592-595,共4页
构造了一类样条的拟插值算子且通过这类算子给出了Cardinal样条对Besov空间的逼近和刻画 .
关键词 Cardinal样条 BESOV空间 逼近 刻画
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基于样条曲线拟合的肺区轮廓修补算法 被引量:2
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作者 钟灵 张建州 张九龙 《计算机应用研究》 CSCD 北大核心 2007年第9期305-306,共2页
当肿瘤处于肺的边缘时,依据CT图像分割出的肺区有缺陷,肿瘤可能被排除在分割出的肺区外。为了解决这一问题,根据肺区外侧轮廓的形状特征,抽取多个控制点,使用Cardinal样条曲线拟合肺区轮廓。拟合后的边界成功地把肿瘤包含在肺区内。
关键词 肺区轮廓 Cardinal样条 拟合
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三次C-Cardinal样条曲线及曲面 被引量:5
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作者 吴晓勤 严秀坤 《计算机工程与科学》 CSCD 2006年第2期48-50,共3页
本文给出了一组特殊的基函数,由此生成的曲线称为三次C-Cardinal样条曲线,是Cardinal样条曲线的推广,形状调整依赖于参数λ和α。当α→0时,所给的曲线是Cardinal样条曲线。运用张量积讨论了曲面的情形,具有与曲线完全类似的性质。实例... 本文给出了一组特殊的基函数,由此生成的曲线称为三次C-Cardinal样条曲线,是Cardinal样条曲线的推广,形状调整依赖于参数λ和α。当α→0时,所给的曲线是Cardinal样条曲线。运用张量积讨论了曲面的情形,具有与曲线完全类似的性质。实例表明,该曲线/面可用于曲线曲面造型。 展开更多
关键词 C-曲线 Cardinal样条 插值
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多元Cardinal样条逼近 被引量:3
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作者 杨柱元 刘永平 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第3期221-223,共3页
讨论了多元Cardinal样条和平移不变子空间对Besov空间的逼近和刻画.
关键词 BESOV空间 Cardinal样条 平移不变子空间
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基于多平面重建提取冠脉轮廓线的曲面重建算法 被引量:1
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作者 侯贺 吕晓琪 +1 位作者 贾东征 于荷峰 《计算机应用》 CSCD 北大核心 2015年第1期211-214,219,共5页
针对三维切割及多平面重建只能获取组织或器官的几何平面信息,无法将弯曲结构的组织或器官展示在单张图片上的问题,实现了基于多平面重建(MPR)提取轮廓线的冠脉曲面重建(CPR)算法。首先,利用多平面重建获取冠脉轮廓的离散点;然后,... 针对三维切割及多平面重建只能获取组织或器官的几何平面信息,无法将弯曲结构的组织或器官展示在单张图片上的问题,实现了基于多平面重建(MPR)提取轮廓线的冠脉曲面重建(CPR)算法。首先,利用多平面重建获取冠脉轮廓的离散点;然后,对离散点进行Cardinal样条插值,获取平滑的轮廓拟合曲线;其次,沿着感兴趣方向对轮廓线进行投影形成扫描曲面;最后,显示扫描曲面对应的心脏体数据,得到冠脉重建曲面。实验结果表明,在绘制速度上,与三维切割法和三维数据场法相比,冠脉轮廓线提取速度提高了每秒4~6帧,绘制时间较短。在绘制质量上,与三维分割法相比,得到的冠脉曲面成像清晰,结构完整,有助于医师对病变的直观分析,能满足实际临床诊疗需求。 展开更多
关键词 多平面重建 轮廓提取 曲线拟合 Cardinal样条 曲面重建
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多元cardinal样条空间的极值性质(英文) 被引量:1
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作者 许贵桥 刘永平 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第5期607-611,共5页
通过研究多元cardinal样条函数插值的逼近性质 ,给出了各向异性Sobolev光滑函数类Wr∞(Rd)在L∞(Rd)尺度下最佳逼近的弱渐近估计 .这个结果表明 ,多元cardinal样条函数空间是各向异性Sobolev光滑类Wr∞(Rd)在L∞(Rd)尺度下关于无穷维Kol... 通过研究多元cardinal样条函数插值的逼近性质 ,给出了各向异性Sobolev光滑函数类Wr∞(Rd)在L∞(Rd)尺度下最佳逼近的弱渐近估计 .这个结果表明 ,多元cardinal样条函数空间是各向异性Sobolev光滑类Wr∞(Rd)在L∞(Rd)尺度下关于无穷维Kolmogorov宽度的弱渐近极子空间 ,也表明多元cardinal样条函数插值是实现线性宽度的最优算子 . 展开更多
关键词 多元cardinal样条 无穷维宽度 极子空间 逼近
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基于角点PRM的移动机器人路径规划 被引量:3
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作者 宋宇 王志明 《长春工业大学学报》 CAS 2019年第4期344-348,共5页
首先使用Harris角点检测算法产生给定地图环境的角点,再从所有角点中取出一定数量的可行点,最后,执行A*算法后使用Cardinal样条曲线进行路径平滑。在不同地图中,将该算法与其他改进PRM算法对比,制定路径长度与算法用时2个指标,仿真结果... 首先使用Harris角点检测算法产生给定地图环境的角点,再从所有角点中取出一定数量的可行点,最后,执行A*算法后使用Cardinal样条曲线进行路径平滑。在不同地图中,将该算法与其他改进PRM算法对比,制定路径长度与算法用时2个指标,仿真结果表明,基于角点PRM算法提高了窄通道通过率达52%,路径长度最多减少了3%,算法用时最多减少了59%。 展开更多
关键词 PRM HARRIS 路径规划 Cardinal样条曲线 路径优化
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椭圆型Cardinal样条 被引量:1
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作者 杨柱元 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第2期185-189,共5页
获得Rd上齐次椭圆型Cardinal样条插值的存在唯一性,并获得Sobolev类上的函数在Lp(Rd)(1≤p≤∞)尺度下的插值误差估计,以及Sobolev类在L2(Rd)尺度下的一些极值问题的解;拓广了Laplace型的结果.
关键词 齐次 椭圆型 Cardinal样条 插值 逼近阶
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基于Cardinals三次样条曲线的航迹生成算法实现 被引量:1
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作者 张瑞峰 倪世宏 《计算技术与自动化》 2006年第S2期109-111,共3页
根据军用飞机飞行参数记录系统提供的飞行数据,提出一种利用Cardinals三次样条曲线进行航迹生成的算法。经过对离散点航迹误差修正及样条曲线的讨论,给出实时计算任意时间点飞机质心位置的公式,为开发可在普通PC机上运行的军用战机飞行... 根据军用飞机飞行参数记录系统提供的飞行数据,提出一种利用Cardinals三次样条曲线进行航迹生成的算法。经过对离散点航迹误差修正及样条曲线的讨论,给出实时计算任意时间点飞机质心位置的公式,为开发可在普通PC机上运行的军用战机飞行过程再现软件,提供了条件。 展开更多
关键词 飞行过程再现 飞行参数记录系统 Cardinals三次样条曲线
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