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THE DIMENSION OF SPLINE SPACE S_3~1(△) ON A TYPE OF TRIANGULATION
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作者 张湘伟 林意 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第8期869-878,共10页
A harmonic condition that can distinguish whether the dimension of spline space S 1 3( △ ) depends on the geometrical character of triangulation is presented, then on a type of general triangulation the dimension... A harmonic condition that can distinguish whether the dimension of spline space S 1 3( △ ) depends on the geometrical character of triangulation is presented, then on a type of general triangulation the dimension is got. 展开更多
关键词 triangulAtION spline space harmonic condition
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椭圆形K空间填充技术结合T2 Space序列在青光眼视神经成像中的应用研究 被引量:1
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作者 戚玉龙 张辉 +3 位作者 冯飞 李金瑛 刘维湘 成官迅 《中国CT和MRI杂志》 2019年第9期30-32,86,共4页
目的在青光眼病人的视神经MRI成像过程中,探讨特殊的K空间填充技术以提升3D高清T2 Space序列的扫描效率。方法将入组的23例青光眼并视力下降行视神经MR扫描的患者按随机数字表法分为传统K空间填充技术法组(A组)和椭圆形K空间填充技术法... 目的在青光眼病人的视神经MRI成像过程中,探讨特殊的K空间填充技术以提升3D高清T2 Space序列的扫描效率。方法将入组的23例青光眼并视力下降行视神经MR扫描的患者按随机数字表法分为传统K空间填充技术法组(A组)和椭圆形K空间填充技术法组(B组),测量两组图像的信噪比,并对两组视神经图像进行主观质量评分,另在水模上分别计算两种不同技术的信噪比。结果两组视神经T2Space图像的信噪比和主观图像质量差异均无统计学意义(P值均>0.05),通过水模计算的信噪比没有明显差异(27.27/27.31)。结论采用椭圆柱形K空间填充方法的T2 Space序列在保证图像质量的基础上成像时间短,效率更高。 展开更多
关键词 青光眼 视神经 t2 space K空间 磁共振成像
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高分辨率血管壁成像时3D SPACE T1压脂与非压脂序列对MCA狭窄病人图像信号、血管壁及斑块的影响
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作者 董乐 《影像研究与医学应用》 2023年第9期90-92,共3页
目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12... 目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12月于滨州市中心医院接受颅内磁共振血管成像(MR angiography,MRA)检查并确诊的MCA狭窄患者72例为研究对象,患者均接受MCA MRI检查,然后再分别用3D SPACE T1压脂与非压脂序列测量,分析图像信号差异情况,对比不同序列测量的血管断面、管腔及斑块面积情况及图像质量主观评价;分析不同医师图像质量评分的一致性情况。结果:72例患者中,不同序列测量均可以清晰地将MCA斑块显示出来,但测量出的信号存在明显的差异。不同序列测量血管断面、管腔面积对比差异不显著(P>0.05);3D SPACE T1非压脂序列测量斑块面积大于压脂序列测量面积(P<0.05);2种序列管腔显示情况对比差异无统计学意义(P>0.05),其他图像质量对比差异有统计学意义(P<0.05)。2名医生图像质量评分具有良好的一致性。结论:高分辨率血管壁成像时3D SPACE T1非压脂序更有助于对MCA狭窄病人图像信号、血管壁及斑块的测量,可为临床提供治疗依据。 展开更多
关键词 高分辨率血管壁成像 3D space t1压脂序列 非压脂序列 大脑中动脉狭窄 图像质量
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爆炸载荷作用下钢筋混凝土预应力T梁桥毁伤模式研究
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作者 徐其鹏 唐泓 翟红波 《包装工程》 CAS 北大核心 2024年第21期253-259,共7页
目的研究不同打击模式下钢筋混凝土预应力T梁桥的毁伤效应,为钢筋混凝土预应力T梁桥的毁伤评估及打击决策提供参考。方法通过数值仿真研究某弹药装药空中爆炸、接触爆炸和内爆炸3种打击模式下,钢筋混凝土预应力T梁桥的毁伤效应。结果不... 目的研究不同打击模式下钢筋混凝土预应力T梁桥的毁伤效应,为钢筋混凝土预应力T梁桥的毁伤评估及打击决策提供参考。方法通过数值仿真研究某弹药装药空中爆炸、接触爆炸和内爆炸3种打击模式下,钢筋混凝土预应力T梁桥的毁伤效应。结果不同打击模式下钢筋混凝土预应力T梁桥的毁伤模式差异较大:空中爆炸和接触爆炸桥梁主要发生桥面破孔及塑性变形;内爆炸桥梁除桥面发生层裂破碎外,T梁腹板及横隔梁也发生外凸变形、混凝土崩塌破坏等。结论半密闭空间内爆炸T梁桥的毁伤效果要优于桥面接触爆炸和空中爆炸。 展开更多
关键词 t梁桥 空中爆炸 接触爆炸 内爆炸 钢筋混凝土 毁伤效应
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Assessment of Changes in the Cesarean Scar and Uterus Between One and Two Years after Cesarean Section Using 3D T2w SPACE MRI 被引量:4
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作者 Yafei Qi Yonglan He +5 位作者 Ning Ding Liangkun Ma Tianyi Qian Yuan Li Huadan Xue Zhengyu Jin 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第2期151-158,共8页
Objective Io evaluate changes in morphology of the cesarean scar and uterus between one and two years after cesarean section using high-resolution,three dimensional T2-weighted sampling perfection with application opt... Objective Io evaluate changes in morphology of the cesarean scar and uterus between one and two years after cesarean section using high-resolution,three dimensional T2-weighted sampling perfection with application optimized contrast using diflerent flip angle evolutions Magnetic Resonance Imaging(3DT2w SPACE MRI).Methods This prospective study was performed to investigate morphological changes in the cesarean scars and uterus from one to two years after cesarean section using high-resolution,3D T2w SPACE MRI.The healthy volunteers having no childbearing history were recruited as the controls.All data were measured by two experienced radiologists.All data with normal distribution between the one-year and two-year groups were compared using a paired-sample t test or independent t test.Results Finally,46 women took a pelvic MR examination one year after cesarean section,and a subset of 15 completed the same examination again after two years of cesarean section.Both the uterine length and the anterior wall thickness after two years of cesarean section(5.75±0.46 and 1.45±0.35 cm)were significantly greater than those measured at one year(5.33±0.59 and 1.25±0.27 cm)(t=-2.363 and-2.175,P=0.033 and 0.048).No significant difference was shown in myometrial thickness two years after cesarean section(1.45±0.35 cm)with respect to the control group(1.58±0.21 cm,P=0.170).Nine women who underwent MRI twice were considered to have scar diverticula one year after cesarean section,and still had diverticula two years after cesarean section.The thickness,height,and width of the uterine scar showed no significant change from one to two years(all P>0.05).Conclusions 3D T2w SPACE MRI provides overall morphologic details and shows dynamic changes in the scar and the uterus between one and two years after cesarean section.Scar morphology after cesarean section reached relatively stable one year after cesarean section,and uterine morphology was closer to normal two years after cesarean section. 展开更多
关键词 uterine cesarean SCAR uterine morphology 3D t2w space MRI
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常规T2-STIR序列联合增强3D-STIR-SPACE序列扫描技术在婴幼儿分娩性臂丛神经损伤诊断中的应用价值 被引量:9
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作者 苏晓然 陈琬 郑彬 《现代医用影像学》 2017年第5期1336-1338,共3页
目的:探讨3D-STIR SPACE序列扫描技术在婴幼儿分娩性臂丛神经损伤中的应用效果及价值。方法:选取2015年1月-2016年12月笔者所在医院收治的30例分娩性臂丛神经损伤患儿资料进行分析,入选患儿均采用MRI常规T2-STIR序列及增强3D-STIR SPAC... 目的:探讨3D-STIR SPACE序列扫描技术在婴幼儿分娩性臂丛神经损伤中的应用效果及价值。方法:选取2015年1月-2016年12月笔者所在医院收治的30例分娩性臂丛神经损伤患儿资料进行分析,入选患儿均采用MRI常规T2-STIR序列及增强3D-STIR SPACE序列,将获得图像进行处理,分析患儿常规T2-STIR序列及增强3D-STIR SPACE序列影像表现,从而评价常规T2-STIR序列联合3D-STIR SPACE序列扫描技术在婴幼儿分娩性臂丛神经损伤中的应用效果及价值。结果:常规T2-STIR序列对臂丛神经椎管内段和椎间孔段进行较好的显示,冠状位上能大致显示臂丛神经向锁骨下及腋窝汇集。增强3D-STIR SPACE序列进行最大密度投影(MIP)及多平面重建(MPR)处理后,可以对臂丛神经干的总体结构进行显示,包括神经干的大小、形态及走向,具有很好的显示效果。结论:常规T2-STIR序列联合增强3D-STIR SPACE序列扫描可以明显提高婴幼儿分娩性臂丛神经损伤的诊断率。 展开更多
关键词 t2-StIR序列 3D-StIR space序列 臂丛神经损伤 磁共振成像
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BOUNDEDNESS OF COMPOSITION OPERATORS ON D_T SPACES FOR T > 1 被引量:1
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作者 胡鹏彦 许卫民 张文俊 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期409-416,共8页
In this note, some conditions of composition operators on DT spaces to be bounded are given by means of Carleson measures and pointwise multipliers, for some ranges of T. The authors prove that (i) Let 1 < T n + 2... In this note, some conditions of composition operators on DT spaces to be bounded are given by means of Carleson measures and pointwise multipliers, for some ranges of T. The authors prove that (i) Let 1 < T n + 2 and 2k < T 2k + 1 (or 2k - 1 < T 2k) for some positive integer k. Suppose = ( 1,… , n) be a univalent mapping from B into itself, denote dμj(l) (z) = R(l) j (z) 2(k-l+2) (1 - z 2)2k-t+1dv(z) for l= 1, 2,… , k + 1. If μj(l)-1 are (T - 2k + 2l-4)-Carleson measures for all l, then the composition operator C on DT is bounded; (ii) Let 1 < T n + 2, = ( 1,… , n) be univalent and the Frechet derivative of -1 be bounded on (B). If R j ∈ M(DT-2) for all j, then the composition operator C on DT is bounded; (iii) Let T > n + 2 and as in (ii). If j ∈ DT for all j, then the composition operator C on DT is bounded. 展开更多
关键词 Composition operator pointwise multiplier t-Carleson measure Dirichlet type space
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Stable Perturbed Algorithms for a New Class of Generalized Nonlinear Implicit Quasi Variational Inclusions in Banach Spaces 被引量:2
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作者 Salahuddin Salahuddin Mohammad Kalimuddin Ahmad 《Advances in Pure Mathematics》 2012年第3期139-148,共10页
In this work, a new class of variational inclusion involving T-accretive operators in Banach spaces is introduced and studied. New iterative algorithms for stability for their class of variational inclusions and its c... In this work, a new class of variational inclusion involving T-accretive operators in Banach spaces is introduced and studied. New iterative algorithms for stability for their class of variational inclusions and its convergence results are established. 展开更多
关键词 t-Accretive Operators VARIAtIONAL INCLUSIONS Iterative Algorithms Stability Conditions Convergence Strong Accretivity BANACH spaces
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T1 THEOREM FOR BESOV SPACES ON NONHOMOGENEOUS SPACES
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作者 Donggao Deng Yanchang Han 《Analysis in Theory and Applications》 2005年第3期280-293,共14页
Suppose μ is a Radon measure on R^d, which may be non doubling. The only condition assumed on μ is a growth condition, namely, there is a constant Co 〉 0 such that for all x ∈ supp(μ) and r 〉 0, μ(B(x, r)... Suppose μ is a Radon measure on R^d, which may be non doubling. The only condition assumed on μ is a growth condition, namely, there is a constant Co 〉 0 such that for all x ∈ supp(μ) and r 〉 0, μ(B(x, r)) ≤ Cor^n, where 0 〈 n ≤ d. We prove T1 theorem for non doubling measures with weak kernel conditions. Our approach yields new results for kernels satisfying weakened regularity conditions, while recovering previously known Tolsa's results. We also prove T1 theorem for Besov spaces on nonhomogeneous spaces with weak kernel conditions given in [7] . 展开更多
关键词 Besov space t1 theorem nonhomogeneous space Calderón-Zygmund operator Littlewood-Paley theory
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SOME PROPERTIES OF STRONGLY MONOTONICALLY T2 SPACES
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作者 Zhao Bin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第4期469-474,共6页
This paper investigates Buck's question about which class of spaces is strongly monotonically T2,and if other properties are combined with strongly monotonically T2,which class of spaces could be got. Based on having... This paper investigates Buck's question about which class of spaces is strongly monotonically T2,and if other properties are combined with strongly monotonically T2,which class of spaces could be got. Based on having a cushioned pair-base space and compact strongly monotonically T2 space,some results (Theorems 1--3) are obtained. 展开更多
关键词 cushioned pair-base compact strongly monotonically t2 operator strongly monotonically t2 space.
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Fixed Point Theorems in Intuitionistics Fuzzy Metric Spaces Using Implicit Relations
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作者 Arun Garg Zaheer K. Ansari Pawan Kumar 《Applied Mathematics》 2016年第6期569-577,共9页
In this paper, we proved some fixed point theorems in intuitionistic fuzzy metric spaces applying the properties of weakly compatible mapping and satisfying the concept of implicit relations for t norms and t connorms.
关键词 Intuitionistic Fuzzy Metric spaces Weakly Compatible Mapping Implicit Relations for t Norms and t Connorms
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Gravitational Space-Time Quantization for Charged Wormholes and the Diophantine Uncertainty Relation 被引量:1
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作者 Yu. A. Khlestkov A. Yu. Khlestkov +2 位作者 P. Yu. Lukashin M. Yu. Lukashin N. Yu. Lukashina 《Journal of Modern Physics》 2020年第11期1761-1778,共18页
This research work proceeds from the assumption, which was still considered by Einstein, that the quantization of gravity does not require additional external procedures: quantum phenomena can be a consequence of the ... This research work proceeds from the assumption, which was still considered by Einstein, that the quantization of gravity does not require additional external procedures: quantum phenomena can be a consequence of the properties of the universal gravitational interaction, which maps any physical field upon the space-time geometry. Therefore, an attempt is made in this research work to reduce the quantization of physical fields in GRT to the space-time quantization. Three reasons for quantum phenomena are considered: Partition of space-time into a set of unconnected Novikov’s R- and T-domains impenetrable for light paths;the set is generated by the invariance of Einstein’s equations with respect to dual mappings;The existence of electric charge quanta of wormholes, which geometrically describe elementary particles in GRT. This gives rise to a discrete spectrum of their physical and geometric parameters governed by Diophantine equations. It is shown that the fundamental constants (electric charge, rest masses of an electron and a proton) are interconnected arithmetically;The existence of the so-called Diophantine catastrophe, when fluctuations in the values of physical constants tending to zero lead to fluctuations in the number of electric charges and the number of nucleons at the wormhole throats, which tend to infinity, so that the product of the increments of these numbers by the increment of physical constants forms a relation equivalent to the uncertainty relation in quantum mechanics. This suggests that space-time cannot but fluctuate, and, moreover, its fluctuations are bounded from below, so that all processes become chaotic, and the observables become averaged over this chaos. 展开更多
关键词 Quantization of Gravitation Novikov’s R- and t-Domains Diophantine Uncertainty Relations Discretization of space-time
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FM Space Depend on Operator T and the Normal Solvability of Operator Polynomial P(T)
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作者 Han Liubing(Dept. of Appl. Math. Southwest Jiaotong University, Chengdu, 610031 ) 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第1期78-81,共4页
In this paper,generalized the ideas of theory of distributions,defined locally convex space depend on operator T,given a new method to change the study of a unbounded operator to a bounded operator, and proved the nor... In this paper,generalized the ideas of theory of distributions,defined locally convex space depend on operator T,given a new method to change the study of a unbounded operator to a bounded operator, and proved the normal solvability of operator polynomial P (T) on FM space that depend on operator T. 展开更多
关键词 FM space:operator t
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基于厚尾双学生氏t分布的非线性状态空间系统鲁棒辨识方法
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作者 刘鑫 海洋 代伟 《电子学报》 EI CAS CSCD 北大核心 2024年第9期3052-3064,共13页
状态空间模型作为一种常见且重要的模型结构在自动化领域有着广泛的应用,本文针对异常值干扰下的非线性状态空间系统辨识问题开展研究.与现有的辨识方法不同,本文充分考虑了状态转移过程和输出量测过程均受到异常值干扰的情况,提出了一... 状态空间模型作为一种常见且重要的模型结构在自动化领域有着广泛的应用,本文针对异常值干扰下的非线性状态空间系统辨识问题开展研究.与现有的辨识方法不同,本文充分考虑了状态转移过程和输出量测过程均受到异常值干扰的情况,提出了一种更加全面的鲁棒辨识算法.首先利用两个相互独立的学生氏t分布分别对状态噪声和输出噪声进行建模以保障算法的鲁棒性;其次利用粒子平滑算法估计状态变量的后验概率分布以解决状态未知问题;最后利用期望最大化算法实现未知参数估计.在算法实现过程中使用了学生氏t分布表达式的数学分解,这样做的好处是:(1)更加有利于算法的推导和实现;(2)更清晰地解释了算法的鲁棒性能.并且本文通过数值算例和应用算例验证了该方法的有效性. 展开更多
关键词 非线性状态空间系统 鲁棒辨识 学生氏t分布 粒子平滑 期望最大化算法
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Fixed Point Theorems in Fuzzy Inner Product Spaces
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作者 Mohd. Rafi Segi Rahmat 《模糊系统与数学》 CSCD 北大核心 2008年第3期89-96,共8页
In this paper,we obtain some new fixed point theorems in fuzzy-Banach spaces by considering the t-norms of h-type and a linear mapping of weakly demicompact.
关键词 模糊数学 空间转换 线性公式 数学分析
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Some Results of Upper and Lower <i>M</i>-Asymmetric Irresolute Multifunctions in Bitopological Spaces 被引量:1
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作者 Levy K. Matindih Edwin Moyo +1 位作者 Davy K. Manyika Timothy Sinyangwe 《Advances in Pure Mathematics》 2021年第6期611-627,共17页
In this paper, we aim to introduce and study some basic properties of upper and lower <em>M</em>-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces wi... In this paper, we aim to introduce and study some basic properties of upper and lower <em>M</em>-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces with certain minimal structures as a generalization of irresolute functions deal to Crossley and Hildebrand <a href="#ref1">[1]</a> and upper and lower irresolute Multifunctions deal to Popa <a href="#ref2">[2]</a>. 展开更多
关键词 titj-Semiopen Sets M-space M-Asymmetric Semiopen and Semiclosed Sets Upper (Lower) Irresolute Multifunctions and Upper (Lower) M-Asymmetric Irresolute Multifunctions
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Commutators of Littlewood-Paley Operators on Herz Spaces with Variable Exponent
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作者 Hongbin Wang Yihong Wu 《Analysis in Theory and Applications》 CSCD 2016年第2期149-163,共15页
Let Ω ∈ L^2(S^n-1) be homogeneous function of degree zero and b be BMO functions. In this paper, we obtain some boundedness of the Littlewood-Paley Opera- tors and their higher-order commutators on Herz spaces wit... Let Ω ∈ L^2(S^n-1) be homogeneous function of degree zero and b be BMO functions. In this paper, we obtain some boundedness of the Littlewood-Paley Opera- tors and their higher-order commutators on Herz spaces with variable exponent. 展开更多
关键词 Herz space variable exponent COMMUtAtOR area integral Littlewood-Paley gλ* func-t-ion.
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(Φ,△)-TYPE PROBABILISTIC CONTRACTOR AND SOLUTIONS FOR A NONLINEAR OPERATOR EQUATIONS IN MENGER PN-SPACES
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作者 方锦暄 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第6期515-521,共7页
The purpose of this paper is to introduce the coneept of (Φ,△)-type probabilistic contractor in Menger PN-spaces and to study the existence and uniqueness of solutions for the nonlinear operator equations with such ... The purpose of this paper is to introduce the coneept of (Φ,△)-type probabilistic contractor in Menger PN-spaces and to study the existence and uniqueness of solutions for the nonlinear operator equations with such probabilistic contractor in Menger PN-spaces.The results presented in this paper improve and extend the corresponding results in [1] and [4-8]. 展开更多
关键词 Menger PN-space t-norm of h-type. probabilistic contractor operator equation
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Research on a toolpath generation method of NC milling based on space-filling curve
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作者 隋秀凛 Chen Xiaoqi +1 位作者 Ge Jianghua Jiao Yan 《High Technology Letters》 EI CAS 2017年第4期418-425,共8页
Tool path generated by space-filling curve always turns frequently causing trembling to machine,reducing toollife and affecting workpiece quality. Length and generation time of tool paths are both relatively long. In ... Tool path generated by space-filling curve always turns frequently causing trembling to machine,reducing toollife and affecting workpiece quality. Length and generation time of tool paths are both relatively long. In order to solve these problems,a toolpath generation method of NC milling based on space-filling curve is proposed. First,T-spline surface is regarded as the modeling surface,the grid,which is based on the limited scallop-height,can be got in the parameter space,and the influence value of grid node is determined. Second,a box is defined and planned,and the tool paths are got preliminarily,which is based on minimal spanning tree; Finally,based on an improved chamfering algorithm,the whole tool paths are got. A simulation system is developed for computer simulation,and an experiment is carried out to verify the method. The results of simulation and experiment show that the method is effective and feasible,and length and time of the tool paths are reduced. 展开更多
关键词 space-filling curve toolpath generation method NC milling t-spline surface minimal spanning tree
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Intuitionistic Menger inner product spaces and applications to integral equations
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作者 张石生 M.GOUDARZI +1 位作者 R.SAADATI S.M.VAEZPOUR 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第4期415-424,共10页
In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the result... In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the results are used to study the existence and uniqueness of the solution to a linear Volterra integral equation. 展开更多
关键词 intuitionistic Menger inner product space Volterra integral equation h-type t-norm fixed point theorem
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