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The(Homotopy)Fixed Point Set of S^(1)-Actions on Rationally Elliptic 4-Manifolds
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作者 Chen Huimin Liu Xiugui 《南开大学学报(自然科学版)》 北大核心 2025年第3期32-37,共6页
Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rationa... Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rational homotopy type of the fixed point set X^(S^(1))is determined. 展开更多
关键词 rationally elliptic 4-manifolds rational homotopy type homotopy fixed point set fixed point set
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A Sparse Depth Point Set Matching Method Based on Panoramic Disparity
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作者 LIU Shuai ZHAO Lingli +1 位作者 CHEN Jun SUN Min 《Journal of Geodesy and Geoinformation Science》 2025年第3期92-107,共16页
The existing panoramic image matching methods are difficult to overcome the non-uniform features of the projection transformation of the target object,and hence the issue of unstable corresponding points matching is u... The existing panoramic image matching methods are difficult to overcome the non-uniform features of the projection transformation of the target object,and hence the issue of unstable corresponding points matching is usually induced.This paper aims to solve the difficulty by proposing a sparse depth point set matching method based on panoramic disparity.By constructing a panoramic disparity model of stereo panoramic images,the disparity between corresponding points can be precisely estimated,and the robustness and effectiveness of corresponding points matching between stereo panoramic images is improved under the epipolar geometric constraints.Firstly,by defining the panoramic disparity,the corresponding angle of panoramic disparity is derived,and the matching areas of corresponding points based on the disparity corresponding angle difference are partitioned.Secondly,the optimization strategy in the matching process of corresponding points is constructed to provide stable matching results for generating sparse depth maps based on the disparity region range and epipolar geometric relationship.Experiments show that the proposed method can not only obtain more stable matching results but also exhibit higher computational efficiency than existing algorithms. 展开更多
关键词 panoramic disparity sparse depth point set feature matching
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Fractional Discrete-Time Analysis of an Emotional Model Built on a Chaotic Map through the Set of Equilibrium and Fixed Points
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作者 Shaher Momani Rabha W.Ibrahim Yeliz Karaca 《Computer Modeling in Engineering & Sciences》 2025年第4期809-826,共18页
Fractional discrete systems can enable the modeling and control of the complicated processes more adaptable through the concept of versatility by providing systemdynamics’descriptions withmore degrees of freedom.Nume... Fractional discrete systems can enable the modeling and control of the complicated processes more adaptable through the concept of versatility by providing systemdynamics’descriptions withmore degrees of freedom.Numerical approaches have become necessary and sufficient to be addressed and employed for benefiting from the adaptability of such systems for varied applications.A variety of fractional Layla and Majnun model(LMM)system kinds has been proposed in the current work where some of these systems’key behaviors are addressed.In addition,the necessary and sufficient conditions for the stability and asymptotic stability of the fractional dynamic systems are investigated,as a result of which,the necessary requirements of the LMM to achieve constant and asymptotically steady zero resolutions are provided.As a special case,when Layla and Majnun have equal feelings,we propose an analysis of the system in view of its equilibrium and fixed point sets.Considering that the system has marginal stability if its eigenvalues have both negative and zero real portions,it is demonstrated that the system neither converges nor diverges to a steady trajectory or equilibrium point.It,rather,continues to hover along the line separating stability and instability based on the fractional LMM system. 展开更多
关键词 Fractional difference system fractional differential operators fractional calculus chaotic map EQUILIBRIUM fixed point sets nyquist plot routh-Hurwitz criterion
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基于Pointnet++的花生植株三维模型器官分割研究
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作者 孟兆凡 程曼 +1 位作者 袁洪波 赵欢 《中国农机化学报》 北大核心 2026年第1期118-127,共10页
基于点云进行三维重构并进行器官分割对植物学研究至关重要,为研究花生植株茎叶器官分割训练样本的数量和类型对分割结果的影响规律,基于Pointnet++构建花生植株三维模型茎叶分割网络模型,并对比分析训练集类型以及数量对分割效果的影... 基于点云进行三维重构并进行器官分割对植物学研究至关重要,为研究花生植株茎叶器官分割训练样本的数量和类型对分割结果的影响规律,基于Pointnet++构建花生植株三维模型茎叶分割网络模型,并对比分析训练集类型以及数量对分割效果的影响。当训练集为10株花生幼苗期数据时,模型分割效果最好,准确率、类平均准确率、类平均交并比、F1分数分别为94.5%、81.9%、76.9%、85.7%。其中,在花生荚果期训练集中加入20株开花期数据,类平均准确率、类平均交并比分别上升19.55%、20.75%。试验结果表明,Pointnet++可以有效分割花生植株茎叶器官,训练集的多样性和数据量的增加有利于模型学习花生植株不同生长阶段的形态特征,在训练集中加入相近生长阶段和生长特征的模型数据,并增加数据量对模型分割效果提高更明显。 展开更多
关键词 花生植株 三维建模 点云 器官分割 训练集
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VARIABILITY OF BUILDING SIMULATION RESULTS DEP ENDING ON SELECTED WEATHER FILES AND CONDITIONING SET POINTS-A CASE STUDY FOR A RESIDENTIAL BUILDING IN VICTORIA,AUSTRALIA
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作者 Astrid Roetzel 《Journal of Green Building》 2016年第4期91-108,共18页
Building simulation is a powerful way to evaluate the performance of a building.The quality of simulation results however strongly depends on the accuracy of simulation input data.Especially for weather data files and... Building simulation is a powerful way to evaluate the performance of a building.The quality of simulation results however strongly depends on the accuracy of simulation input data.Especially for weather data files and occupant behaviour it is difficult to obtain accurate data.This paper evaluates the variability of building simulation results with regards to different weather data sets as well as different heating and cooling set points for a residential building in Victoria,Australia.Thermal comfort accord-ing to ASHRAE Standard 55,final energy consumption and peak cooling and heating loads are assessed.Simulations have been performed with Energy-Plus,and weather data for a multi-year approach have been generated with the software Meteonorm.The results show that different weather files for the same location as well as different conditioning set points can influence the results by approximately a factor of 2. 展开更多
关键词 weather data occupant behaviour heating and cooling set points residential building building simulation energy performance peak loads adaptive thermal comfort
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INVOLUTIONS WITH FIXED POINT SET RP(2m)∪P(2m, 2n + 1) 被引量:4
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作者 孟媛媛 王彦英 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期331-342,共12页
Let (M, T) be a smooth closed manifold with a smooth involution T whose fixed point set is a disjoint union of an even-dimensional real projective space and a Dold manifold. In some cases, the equivariant bordism cl... Let (M, T) be a smooth closed manifold with a smooth involution T whose fixed point set is a disjoint union of an even-dimensional real projective space and a Dold manifold. In some cases, the equivariant bordism classes of (M, T) are determined. 展开更多
关键词 INVOLUTION fixed point set characteristic class bordism class
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Curvature Estimation of Point Set Data Based on the Moving-Least Square Surface 被引量:1
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作者 邱彦杰 周雄辉 +1 位作者 杨平海 钱小平 《Journal of Shanghai Jiaotong university(Science)》 EI 2011年第4期402-411,共10页
Curvature estimation is a basic step in many point relative applications such as feature recognition, segmentation,shape analysis and simplification.This paper proposes a moving-least square(MLS) surface based method ... Curvature estimation is a basic step in many point relative applications such as feature recognition, segmentation,shape analysis and simplification.This paper proposes a moving-least square(MLS) surface based method to evaluate curvatures for unorganized point cloud data.First a variation of the projection based MLS surface is adopted as the underlying representation of the input points.A set of equations for geometric analysis are derived from the implicit definition of the MLS surface.These equations are then used to compute curvatures of the surface.Moreover,an empirical formula for determining the appropriate Gaussian factor is presented to improve the accuracy of curvature estimation.The proposed method is tested on several sets of synthetic and real data.The results demonstrate that the MLS surface based method can faithfully and efficiently estimate curvatures and reflect subtle curvature variations.The comparisons with other curvature computation algorithms also show that the presented method performs well when handling noisy data and dense points with complex shapes. 展开更多
关键词 curvature estimation moving-least square(MLS) surface point set Gaussian factor
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m-degree Center-connecting Line of Finite Points Set and Its Properties 被引量:1
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作者 ZHOU Yong-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期247-252,共6页
In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formu... In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formula in finite points set. As its application,we extend the Leibniz formula and length of medians formula in n-dimensional simplex to polytope. 展开更多
关键词 n-dimensional Euclidean space finite points set m-degree center-connectingline PROPERTIES
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A Correntropy-based Affine Iterative Closest Point Algorithm for Robust Point Set Registration 被引量:7
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作者 Hongchen Chen Xie Zhang +2 位作者 Shaoyi Du Zongze Wu Nanning Zheng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期981-991,共11页
The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy outliers.To solve this prob... The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy outliers.To solve this problem,we propose a new affine registration algorithm based on correntropy which works well in the affine registration of point sets with outliers.Firstly,we substitute the traditional measure of least squares with a maximum correntropy criterion to build a new registration model,which can avoid the influence of outliers.To maximize the objective function,we then propose a robust affine ICP algorithm.At each iteration of this new algorithm,we set up the index mapping of two point sets according to the known transformation,and then compute the closed-form solution of the new transformation according to the known index mapping.Similar to the traditional ICP algorithm,our algorithm converges to a local maximum monotonously for any given initial value.Finally,the robustness and high efficiency of affine ICP algorithm based on correntropy are demonstrated by 2D and 3D point set registration experiments. 展开更多
关键词 AFFINE ITERATIVE closest point(ICP)algorithm correntropy-based ROBUST point set REGISTRATION
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Environmental Risk Factors for Stomach Cancer in an African Setting about 193 Cases at the CHU Point G in Bamako/Mali 被引量:2
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作者 Souleymane Sanogo Drissa Traoré +8 位作者 Mamadou Coulibaly Birama Togola Bréhima Bengaly Ousmane Ibréhima Touré Drissa Ouattara Bréhima Coulibaly Babou Ba Siaka Diallo Nouhoum Ongoiba 《Surgical Science》 2021年第2期23-30,共8页
CHU (University Hospital Center) Point G: The department of surgery B is a surgical department of CHU Point G. The department is par excellence a reference department for cases of visceral surgery, cancer surgery, car... CHU (University Hospital Center) Point G: The department of surgery B is a surgical department of CHU Point G. The department is par excellence a reference department for cases of visceral surgery, cancer surgery, cardiovascular surgery, plastic and endocrinology surgery. As a reminder, the CHU Point G is the largest 3rd level referral hospital in Mali. <b><span style="font-family:Verdana;">Aim:</span></b><span style="font-family:Verdana;"> To study the environmental risk factors of stomach cancer in the B surgery department of the Point G University Hospital in Bamako. </span><b><span style="font-family:Verdana;">Patients and Methods:</span></b><span style="font-family:Verdana;"> We performed a cross-sectional study with retrospective collection from January 2008 to June 2018 (126 months). </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">We have identified 380 cases of digestive cancer, including 193 cases of stomach cancer </span><span style="font-family:Verdana;">o</span><span style="font-family:;" "=""><span style="font-family:Verdana;">r 50.79% of digestive cancers. The mean age of the patients was 57.21 ± 13 years. Male sex represented 55% (n = 106). Eating habits were dominated by the consumption of t<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&ocirc;</span> with potash (cereal paste) with 64.76% (n = 185). The main methods of preserving meat and fish were curing and smoking with 57.51% (n = 111). Chronic smoking was found in 24.35% (n = 47), alcohol + tobacco consumption in 2.59% (n = 5). The low socio-economic class represented 126 cases or 65.38%. Housewives and cultivators were respectively 37.82% (n = 73) and 227.97% (n = 54). 20.20% (n = 39) had a history of epigastric pain. Epigastralgia was the most common functional sign with 84.5% of cases (n = 169). An epigastric mass was found in 72 patients or 37.3%. Adenocarcinoma represented 97.4% (n = 188). Palliative surgery concerned the majority of our patients with 64.8% of patients (n = 79). The postoperative consequences were simple in 28.57% of cases (n = 28), the postoperative morbidity and mortality were respectively 33.61% (n = 41), and 23.77% (n = 29). The overall survival rate after surgery was 10.81% at 2 years and 2.94% at 5 years. This rate was 58.83% at 2 years and 28.50% at 5 years after curative surgery. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The risk factors for stomach cancer are many and varied. Some are particularly present in Africa. Delay in diagnosis due to a belief in traditional healers is common in our community.</span></span> 展开更多
关键词 Stomach Cancer Environmental Risk Factors African setting CHU point G
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Forward Affine Point Set Matching Under Variational Bayesian Framework 被引量:1
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作者 QU Han-Bing CHEN Xi +1 位作者 WANG Song-Tao YU Ming 《自动化学报》 EI CSCD 北大核心 2015年第8期1482-1494,共13页
关键词 贝叶斯 点集 匹配 仿射 框架 变分 逼近算法 线性变换
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Research on Algorithm of the Point Set in the Plane Based on Delaunay Triangulation 被引量:2
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作者 Bin Yang Shuyuan Shang 《American Journal of Computational Mathematics》 2012年第4期336-340,共5页
In the paper, an improved algorithm is presented for Delaunay triangulation of the point-set in the plain. Based on the original algorithm, we propose the notion of removing circle. During the process of triangulation... In the paper, an improved algorithm is presented for Delaunay triangulation of the point-set in the plain. Based on the original algorithm, we propose the notion of removing circle. During the process of triangulation, and the circle dynamically moves, the algorithm which is simple and practical, therefore evidently accelerates the process of searching a new point, while generating a new triangle. Then it shows the effect of the algorithm in the finite element mesh. 展开更多
关键词 point-set in the PLANE DELAUNAY TRIANGULATION Removing Circle FINITE Element MESH
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Set point optimization of controlled Organic Rankine Cycle systems
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作者 Jianhua Zhang Mingming Lin +2 位作者 Fei Shi Jia Meng Jinliang Xu 《Chinese Science Bulletin》 SCIE EI CAS 2014年第33期4397-4404,共8页
In this paper, an approach to optimize set points is proposed for controlled Organic Rankine Cycle(ORC)systems. Owing to both disturbances and variations of operating point existing in ORC systems, it is necessary to ... In this paper, an approach to optimize set points is proposed for controlled Organic Rankine Cycle(ORC)systems. Owing to both disturbances and variations of operating point existing in ORC systems, it is necessary to optimize the set points for controlled ORC systems so as to improve the energy conversion efficiency. At first, the optimal set points of controlled ORC systems are investigated by revisiting performance analysis and optimization of ORC systems. The expected set points of the evaporating pressure and the temperature at evaporator outlet are then determined by combining genetic algorithm with least squares support vector machine(GA-LSSVM). Simulation results show that the predicted results by GA-LSSVM can be regarded as the optimal set points of controlled ORC systems with varying operating conditions. 展开更多
关键词 优化设置 循环系统 点控制 定点 最小二乘支持向量机 RC系统 能量转换效率 优化设定
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Set-point Filter Design for a Two-degree-of-freedom Fractional Control System
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作者 Fabrizio Padula Antonio Visioli 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第4期451-462,共12页
This paper focuses on a new approach to design(possibly fractional) set-point filters for fractional control systems.After designing a smooth and monotonic desired output signal,the necessary command signal is obtaine... This paper focuses on a new approach to design(possibly fractional) set-point filters for fractional control systems.After designing a smooth and monotonic desired output signal,the necessary command signal is obtained via fractional input-output inversion.Then,a set-point filter is determined based on the synthesized command signal.The filter is computed by minimizing the 2-norm of the difference between the command signal and the filter step response.The proposed methodology allows the designer to synthesize both integer and fractional setpoint filters.The pros and cons of both solutions are discussed in details.This approach is suitable for the design of two degreeof-freedom controllers capable to make the set-point tracking performance almost independent from the feedback part of the controller.Simulation results show the effectiveness of the proposed methodology. 展开更多
关键词 Fractional control systems two-degree-of-freedom control set-point following system inversion
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Finite Type Transcendental Entire Functions Whose Buried Points Set Contains Unbounded Positive Real Interval
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作者 Feng Guo 《Advances in Pure Mathematics》 2014年第5期209-212,共4页
Let fμ(z)=z·ep(z)+μ with p(z) being real coefficient polynomial and it's leading coefficient be positive, μ∈R+, when p(z) and μ satisfy two certain conditions, buried point set of fμ(z) contains unbound... Let fμ(z)=z·ep(z)+μ with p(z) being real coefficient polynomial and it's leading coefficient be positive, μ∈R+, when p(z) and μ satisfy two certain conditions, buried point set of fμ(z) contains unbounded positive real interval. 展开更多
关键词 TRANSCENDENTAL Entire Functions Julia set BURIED pointS set Real INTERVAL
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PI control based on fuzzy set-point weighting tracking for hydraulic crane boom system
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作者 Yong YANG An LUO Karl-Erik RYDBERG 《控制理论与应用(英文版)》 EI 2006年第4期327-330,共4页
A PI control strategy based on fuzzy set-point weighting following was proposed for the active damping control of a hydraulic crane boom system (HCBS). Two valve-controlled PI controllers, which include a proportion... A PI control strategy based on fuzzy set-point weighting following was proposed for the active damping control of a hydraulic crane boom system (HCBS). Two valve-controlled PI controllers, which include a proportional feedforward controller based on fuzzy set-point weighting following and a limited semi-integrator(LSI), are designed respectively. LSI is used to limit output signal and to prevent wind up at the low frequency of the spectrum. By using a range camera and an electronic feedback control, the tip damping on the HCBS can be adjusted artificially. A collaborative control simulation technique of HOPSAN and MATLAB/SIMULINK is applied to the controller design. Simulation results show that the proposed PI control system has less overshoot as well as faster response. The tip damping on the HCBS during operation is improved. 展开更多
关键词 PI control Fuzzy set-point weighting (FSPW) Limited semi-integrator(LSI) Active damping Collaborative control simulation Range camera Hydraulic crane boom system (HCBS)
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Solving Fixed Point Problems in More General Nonconvex Sets Via an Interior Point Homotopy Method
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作者 SU Meng-long LIU Mai-xue 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期74-78,共5页
In this paper,we are mainly devoted to solving fixed point problems in more general nonconvex sets via an interior point homotopy method.Under suitable conditions,a constructive proof is given to prove the existence o... In this paper,we are mainly devoted to solving fixed point problems in more general nonconvex sets via an interior point homotopy method.Under suitable conditions,a constructive proof is given to prove the existence of fixed points,which can lead to an implementable globally convergent algorithm. 展开更多
关键词 nonconvex sets interior point homotopy method
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L_p(1≤p≤∞) APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A SET OF n+1 POINTS
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作者 史应光 《Acta Mathematica Scientia》 SCIE CSCD 1993年第4期430-436,共7页
Some new characterizations and immediate explicit expressions of best L(1≤p≤∞) approximation and their deviations by an n-dimensional subspace on a set of n+1 points are given.
关键词 APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A set OF n+1 pointS L_p ID Case
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EXISTENCE OF POSITIVE FIXED POINTS FOR SEMIDIFFERENTIABLE SEMICOMPACT 1-SET-CONTRACTIONS
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作者 宋建伟 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第7期637-641,共5页
This paper obtains some fixed point theorems of semidifferentiable semicompact 1-set-contraction maps, which extend some known results in [1, 2, 4, 5, 7].
关键词 semidifferentiable semicompact l-set-contraction positive fixed point
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Use of Rough Sets Theory in Point Cluster and River Network Selection
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作者 Jia Qiu Ruisheng Wang Wenjing Li 《Journal of Geographic Information System》 2014年第3期209-219,共11页
In this paper, we applied the rough sets to the point cluster and river network selection. In order to meet the requirements of rough sets, first, we structuralize and quantify the spatial information of objects by co... In this paper, we applied the rough sets to the point cluster and river network selection. In order to meet the requirements of rough sets, first, we structuralize and quantify the spatial information of objects by convex hull, triangulated irregular network (TIN), Voronoi diagram, etc.;second, we manually assign decisional attributes to the information table according to conditional attributes. In doing so, the spatial information and attribute information are integrated together to evaluate the importance of points and rivers by rough sets theory. Finally, we select the point cluster and the river network in a progressive manner. The experimental results show that our method is valid and effective. In comparison with previous work, our method has the advantage to adaptively consider the spatial and attribute information at the same time without any a priori knowledge. 展开更多
关键词 ROUGH sets THEORY Map GENERALIZATION point CLUSTER River Network Progressive SELECTION
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