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AVERAGE σ-K WIDTH OF CONVOLUTION FUNCTION CLASS OF L_(pq) (R) IN L_q(R)
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作者 Liu Yongping Beijing Normal University. Beijing 《Analysis in Theory and Applications》 1994年第1期34-46,共13页
In this paper. we study the average n-K width of the convolution class B_(pq)(G)(or B_(?)(G)), for which the kernel G(x) is a PF density, in the metric L_q(R)(or L_(qp)(R)) for the case 1≤q<p ≤∞, and obtain some... In this paper. we study the average n-K width of the convolution class B_(pq)(G)(or B_(?)(G)), for which the kernel G(x) is a PF density, in the metric L_q(R)(or L_(qp)(R)) for the case 1≤q<p ≤∞, and obtain some exact results. 展开更多
关键词 IN L_q K width OF CONVOLUTION FUNCTION CLASS OF L PQ average Math
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AVERAGE σ-K WIDTH OF CLASS OF L_p(R^n) IN L_q (R^n) 被引量:7
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作者 LIU YONGPING(Department of Mathematics, Beijing Normal University, Beliing 100875, China.) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第3期351-360,共10页
The average σ-K width of the Sobolev-Wiener class in Lq(Rn) is studied for and the asymptotic behaviour of this quantity is determined. The exact value of average σ-K width of some class of smooth functions in L2(Rn... The average σ-K width of the Sobolev-Wiener class in Lq(Rn) is studied for and the asymptotic behaviour of this quantity is determined. The exact value of average σ-K width of some class of smooth functions in L2(Rn) is obtained. 展开更多
关键词 average σ-k width Optimal subspace Sobolev-Wiener class Riesz potential.
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AVERAGE o--K WIDTHS OF SOME GENERALIZED SOBOLEV--WIENER CLASSES
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作者 刘永平 《Analysis in Theory and Applications》 1992年第4期79-88,共10页
In this paper,a kind of generalized Sobolev-Wiener classes W_(pq)~y(R,h),h>0,defined on the whole real axis,is introduced,and the average σ-K width problem of these function classes in the metric L_q(R)is studied.... In this paper,a kind of generalized Sobolev-Wiener classes W_(pq)~y(R,h),h>0,defined on the whole real axis,is introduced,and the average σ-K width problem of these function classes in the metric L_q(R)is studied.For the case p=+∞,1≤q≤+∞,the case 1≤p <+∞,q=1,we get their exact values and identify their optimal subspaces. 展开更多
关键词 WIENER CLASSES average o K widthS OF SOME GENERALIZED SOBOLEV
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WIDTHS AND AVERAGE WIDTHS OF SOBOLEV CLASSES 被引量:1
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作者 刘永平 许贵桥 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期178-184,共7页
This paper concerns the problem of the Kolmogorov n-width, the linear re-width, the Gel'fand n-width and the Bernstein re-width of Sobolev classes of the periodic multivariate functions in the space Lp(Td) and the... This paper concerns the problem of the Kolmogorov n-width, the linear re-width, the Gel'fand n-width and the Bernstein re-width of Sobolev classes of the periodic multivariate functions in the space Lp(Td) and the average Bernstein o-width, average Kolmogorov o-widths, the average linear o-widths of Sobolev classes of the multivariate functions in the space LP(R ), where p = (p1,…,pd), 1 < Pj < ∞o, j = 1,2,…,d, or pj = ∞,j = 1,2,…, d. Their weak asymptotic behaviors are established for the corresponding quantities. 展开更多
关键词 Multivariate function Sobolev class width average width
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PROBABILISTIC AND AVERAGE LINEAR WIDTHS OF SOBOLEV SPACE WITH GAUSSIAN MEASURE IN SPACE S_Q(T)(1≤Q≤∞)
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作者 徐艳艳 陈广贵 +1 位作者 甘莹 许燕 《Acta Mathematica Scientia》 SCIE CSCD 2015年第2期495-507,共13页
Probabilistic linear (N, δ)-widths and p-average linear N-widths of Sobolev space W2^r(T), equipped with a Gaussian probability measure #, are studied in the metric of Sq (T) (1 ≤ Q ≤∞), and determined the... Probabilistic linear (N, δ)-widths and p-average linear N-widths of Sobolev space W2^r(T), equipped with a Gaussian probability measure #, are studied in the metric of Sq (T) (1 ≤ Q ≤∞), and determined the asymptotic equalities:λN,δ(W2^r(T),μ,Sq(T))={(N^-1)^r+p/2-1/q√1+1/N·ln1/δ, 1≤q≤2, (N^-1)^r+p/2-1/q(1+N^-1/q√ln1/δ),2〈q〈∞, (N^-1)^r+p/2√lnN/δ, q=∞,and λN^(a)(W2^r(T),μ,Sq(T))p={(N^-1)^r+p/2-1/q, 1≤q〈∞, (N^-1)^r+p/2-1/q√lnN, q=∞,where 0 〈 p 〈 ∞, δ∈ (0, 1/2], ρ 〉 1, and Sq(T) is a subspace of L1(T), in which the Fourier series is absolutely convergent in lq sense. 展开更多
关键词 Probabilistic linear width average linear width Gaussian measure Sobolevspace linear operator
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AVERAGE ONESIDED WIDTHS OF SOBOLEV AND BESOV CLASSES
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作者 杨柱元 杨宗文 刘永平 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期148-160,共13页
The article concerns the average onesided widths of the Sobolev and Besov classes and the classes of functions with bounded moduli of smoothness. The weak asymptotic results are obtained for the corresponding quantities.
关键词 average onesided widths Sobolev classes Besov classes
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Average Odontometric Value of the Width of the Upper Central Incisor in the Congolese Bantu of Kinshasa, Democratic Republic of Congo
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作者 Kumpanya Ntumba Pierrot Sekele Isourady Bourley Jean Paul +6 位作者 Sekele Marob Ndjock Patrick Nyimi Bushabu Fidele Kayembe Bukama Jean Marie Mudogo Nzanzu Celestin Kashiya Muamba Hyves Mantshumba Milolo Agustin Ntumba Mulumba Hybert 《Open Journal of Stomatology》 2022年第3期77-86,共10页
Objective: The aim of this study was to determine the average values of width of the upper central incisor (WUCI) in Congolese Bantu and compare them to those of Caucasians and Asiatic. Material and Methods: It was a ... Objective: The aim of this study was to determine the average values of width of the upper central incisor (WUCI) in Congolese Bantu and compare them to those of Caucasians and Asiatic. Material and Methods: It was a prospective cross-sectional study carried out at the Université de Kinshasa on the Congolese Bantu, Department of Dental Medicine, from March 2020 to March 2021. A maxillary imprint was taken by Jeltrate-type alginate. The measurement of two healthy upper central incisors (UCI) was carried out by the hard plaster casting type 4, with a brand caliper, carbon fiver composite mark. The study was approved by the Ethics Committee of the School of Public Health in the Université de Kinshasa and verbal consent was obtained from each participant. Results: The Average Width of the UCI was 8.74 mm ± 0.56. The average width of the right Upper Central incisor (RUCI) and the left UCI (LUCI) was 8.71 mm ± 0.57 and 8.77 mm ± 0.56, respectively. The average width of the RUCI and LUCI was not the same for men and women (p 0.001). A significant difference was observed between the average of the RUCI and the 18 - 28 and 40 - 50 age group (p = 0.056) as well as for the average LUCI (p = 0.085). The width average of UCI between the Congolese Bantu with those of Caucasians and Asians was significantly different (p = 0.000 and p = 0.009). Conclusion: The average width of the RUCI and LUCI was different among sex and age group. The average width of UCI of the Congolese Bantu is different from that of Caucasians and Asians. 展开更多
关键词 Odontometry average width Upper Central Incisor Congolese Bantu
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AVERAGE σ-WIDTHS OF THE UNIT BALL OF I_1~∞(R)IN I_2~∞(R)
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作者 Wu Huoxiong Beijing Normal University, China Department of Mathematics Chenzhou Normal College, Hunan, 423000 P R China 《Analysis in Theory and Applications》 1994年第2期92-104,共13页
In this paper we study the average σ-K width and the average σ-linear width of the unit ball of l;(R) inl;(R). The exact values of these widths are calculated and an optimal subspace with the optimal linear oper... In this paper we study the average σ-K width and the average σ-linear width of the unit ball of l;(R) inl;(R). The exact values of these widths are calculated and an optimal subspace with the optimal linear opera-tor (for the σ- linear width) are identified. 展开更多
关键词 Math widthS OF THE UNIT BALL OF I1 average R)IN I2 APPI 飞飞
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Formula for average energy required to produce a secondary electron in an insulator
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作者 谢爱根 詹煜 +1 位作者 高志勇 吴红艳 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期540-542,共3页
Based on a simple classical model specifying that the primary electrons interact with the electrons of a lattice through the Coulomb force and a conclusion that the lattice scattering can be ignored, the formula for t... Based on a simple classical model specifying that the primary electrons interact with the electrons of a lattice through the Coulomb force and a conclusion that the lattice scattering can be ignored, the formula for the average energy required to produce a secondary electron (ε) is obtained. On the basis of the energy band of an insulator and the formula for e, the formula for the average energy required to produce a secondary electron in an insulator (εi) is deduced as a function of the width of the forbidden band (Eg) and electron affinity X. Experimental values and the εi values calculated with the formula are compared, and the results validate the theory that explains the relationships among Eg, X, and ei and suggest that the formula for εi is universal on the condition that the primary electrons at any energy hit the insulator. 展开更多
关键词 width of forbidden band electron affinity average energy INSULATOR
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L^2(R)中界于连续模的光滑函数类的平均σ-K宽度 被引量:1
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作者 刘永平 《北京师范大学学报(自然科学版)》 CAS CSCD 1993年第1期44-49,共6页
研究了L^2(R)中一类界于连续模的光滑函数类在L^2(R)尺度下的平均σ-K宽度且得到其精确值。同时,指出B_σ(?)~2是一个极子空间。
关键词 平均σ-k宽度 连续模 光滑函数
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L^2(R)中界于S-平均连续模的光滑函数类的平均σ-K宽度
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作者 耿爱成 《数学进展》 CSCD 北大核心 2015年第1期84-90,共7页
本文研究了L^2(R)中界于S-平均连续模的光滑函数类在L^2(R)尺度下的平均σ-K宽度,并且得到了d_σ(K(α,p,c),L^2(R))的精确值.同时指出B_(πσ)~2,(R)是实现d_σ(K(α,P,c),L^2(R))的平均σ维极子空间.
关键词 S-平均连续模 平均σ维子空间 平均σ-k宽度 极子空间
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Sensitivity analysis of the vane length and passage width for a radial type swirler employed in a triple swirler configuration 被引量:4
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作者 Foad Vashahi Shahnaz Rezaei +1 位作者 Reza Alidoost Dafsari Jeekeun Lee 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期363-375,共13页
The design of axial or radial swirlers typically governs a number of geometrical parameters that are determined by the desired flow field.In the meantime,the number of unknown parameters increases with the number of c... The design of axial or radial swirlers typically governs a number of geometrical parameters that are determined by the desired flow field.In the meantime,the number of unknown parameters increases with the number of concentrically mounted swirlers.The available literature is nonetheless limited,and designers are obligated to increase the number of initial assumptions.In this article,three kinds of triple swirlers are employed and simulations are performed to determine the effect of each parameter on the swirler performance.Based on the correlation provided,overlengthening the radial vane length could result in significant changes in the flow field from the jetlike pattern to a wide swirl-jet angle due to the Coanda effect.Passage width should also have the potential to alter the swirl-jet angle and velocity field at the exit of the swirler. 展开更多
关键词 TRIPLE SWIRLER SWIRLER design RADIAL VANE length PASSAGE width Reynolds averaged Navier–Stokes
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Crack elongation and its width of large depth reinforced concrete beams 被引量:2
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作者 管俊峰 赵顺波 黄承逵 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期631-635,共5页
In order to meet the requirement of structural inspection,the crack spacing and crack width at various heights in the tensile zone of six large depth reinforced concrete beams were measured under several loading level... In order to meet the requirement of structural inspection,the crack spacing and crack width at various heights in the tensile zone of six large depth reinforced concrete beams were measured under several loading levels of serviceability state.The effects of the depth of normal section beams on the crack spacing and crack width were analyzed,and the modified model is proposed for calculating the average crack spacing by thinking about the depth of normal section,the reinforcement arrangement and the effective reinforcement ratio.The relationships of crack widths at any position in the tensile zone and at the reinforcement level on the side surface of beam were studied.By theoretical and statistical analysis,a method is proposed to calculate the ratios of crack widths between any position and the reinforcement level on the side surface of large depth reinforced concrete beams. 展开更多
关键词 reinforced concrete beam large depth of normal section crack elongation average crack spacing ratio of crack width
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OPTIMAL ALGORITHMS FOR DIAGONAL OPERATORS ON N-WIDTHS IN DIFFERENT COMPUTATIONAL SETTING——In Memory of Professor Sun Yongsheng
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作者 Gensun Fang Lixin Qian 《Analysis in Theory and Applications》 2007年第2期180-187,共8页
In this paper, we give some optimal algorithms for diagonal operator T from space lp(1≤p≤2) to l2 on n-widths in different computational setting.
关键词 Kolmogorov n-width linear n-width linear average n-width linear stochastic n-width
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断面密度对水面线计算结果的敏感性分析
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作者 徐林春 林美兰 刘画眉 《中国农村水利水电》 北大核心 2025年第11期28-32,共5页
水面线是开展水利、水电、交通、航运等涉水工程的规划、设计、研究、建设和管理工作必要的基本参数,其成果的合理性及计算精度十分重要。影响水面线计算结果的因素有很多,如河道地形、水文边界、计算模型、河道糙率等等。模型的离散解... 水面线是开展水利、水电、交通、航运等涉水工程的规划、设计、研究、建设和管理工作必要的基本参数,其成果的合理性及计算精度十分重要。影响水面线计算结果的因素有很多,如河道地形、水文边界、计算模型、河道糙率等等。模型的离散解析、计算参数的调整、糙率的选取、边界取值的差异、阻水建筑物的模拟概化等均会影响水面线的计算结果。针对梯形河道和天然河道研究河道断面布置密度对水面线计算结果的影响,可为水面线计算中合理布置计算断面提供借鉴。断面密度越大,计算精度越高,但由于需要考虑计算弗汝德数和计算效率的问题,断面不能无限加密。研究结果表明,对于顺直型梯形河道,断面密度对计算结果敏感性较小,仅计算结果略有影响。200km计算河道水位最大偏差仅0.0084m,约0.00004m/km。可以认为,对于规则断面顺直河道,断面间距在1km以内即可满足计算精度要求一般断面间距取3倍河宽即可满足计算精度要求。而对于天然河道,断面密度对计算结果有显著影响。各工况随着断面密度的加大,水位偏差幅度逐渐缩小。对于断面间距大于平均河宽5倍的工况,断面密度变化对计算精度没有显著的改善,但当断面间距缩小至平均河宽2~3倍时,可较为显著的提高计算精度。为确保计算精度,断面密度应尽量控制在2倍河宽范围内。 展开更多
关键词 断面密度 断面间距 平均河宽 计算精度 敏感性
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Average Widths of Sobolev-Wiener Classes with Mixed Smoothness in L_q(R^d)
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作者 He Ping WANG Department of Mathematics, Capital Normal University. Beijing, 100037, P. R. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2001年第2期305-312,共8页
In this paper, the average σ-K width of Sobolev-Wiener classes S<sub>pq</sub><sup>r</sup> W with mixed smooth- ness in L<sub>q</sub>(R<sup>d</sup>) is studied for 1【... In this paper, the average σ-K width of Sobolev-Wiener classes S<sub>pq</sub><sup>r</sup> W with mixed smooth- ness in L<sub>q</sub>(R<sup>d</sup>) is studied for 1【q≤p【∞, and the weak asymptotical behavior of these quantities is obtained. 展开更多
关键词 Sobolev-Wiener classes with mixed smoothness average σ-k width Step hyperbolic crosses
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Average widths and optimal recovery of multivariate Besov classes in L_p(R^d) 被引量:4
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作者 Yanjie Jiang Yongping Liu 《Chinese Science Bulletin》 SCIE EI CAS 1998年第8期638-641,共4页
Some weak asymptotic results for average σ-K width and average σ_L width of the isotropic Besov classes S r pθB(R d), S r pθb(R d) and the anisotropic Besov classes S r pθB(R d), S r pθb(R d) in L p(R d) (1≤p&... Some weak asymptotic results for average σ-K width and average σ_L width of the isotropic Besov classes S r pθB(R d), S r pθb(R d) and the anisotropic Besov classes S r pθB(R d), S r pθb(R d) in L p(R d) (1≤p<∞) are obtained, and the corresponding weak asymptotic optimal subspaces are identified. Furthermore, the weak asymptotic behavior of optimal recovery is established for the isotropic Besov classes S r pθB(R d) in L p(R d) (1≤p≤∞). 展开更多
关键词 average DIMENSION average width optimal recovery BESOV class.
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赋Gauss测度的球上加权Sobolev空间中Gel'fand型逼近特征
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作者 刘禹祺 吴瑞欢 李冱岸 《数学进展》 北大核心 2025年第1期113-122,共10页
本文的主要工作是确定定义在欧氏球B^(d)上的加权Sobolev空间W_(2,μ)^(r)(B^(d))在加权q次Lebesgue可积函数空间L_(q,μ)(B^(d))尺度下概率与平均Gel'fand宽度的精确阶,其中权函数为1-‖x‖_(2)~2)^(μ-1/2),μ≥0,且在W_(2,μ)^(r... 本文的主要工作是确定定义在欧氏球B^(d)上的加权Sobolev空间W_(2,μ)^(r)(B^(d))在加权q次Lebesgue可积函数空间L_(q,μ)(B^(d))尺度下概率与平均Gel'fand宽度的精确阶,其中权函数为1-‖x‖_(2)~2)^(μ-1/2),μ≥0,且在W_(2,μ)^(r)(B^(d))中赋以Gauss测度v.本文利用离散化方法得到了概率Gel'fand(n,δ)-宽度的结果,而后利用概率Gel'fand(n,δ)-宽度的结果以及实分析的方法得出了p-平均Gel'fand n-宽度的精确阶. 展开更多
关键词 概率宽度 平均宽度 加权SOBOLEV空间 GAUSS测度
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AVERAGE n-WIDTH OF POINT SET IN HILBERT SPACE 被引量:3
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作者 孙永生 《Chinese Science Bulletin》 SCIE EI CAS 1992年第14期1153-1157,共5页
Given a separable real Banach space F and a separable real Hilbert space X, we denote by S a bounded linear operator from F into X. Let μ be a Gaussian measure defined on the Borel field of F with mean element m_μ= ... Given a separable real Banach space F and a separable real Hilbert space X, we denote by S a bounded linear operator from F into X. Let μ be a Gaussian measure defined on the Borel field of F with mean element m_μ= 0 and correlation operator C_μ. By [1], C_μ is a bounded linear operator from F~*→F such 展开更多
关键词 average n-width HILBERT space GAUSSIAN measure
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基于几何形状建模的光窗裂纹宽度计算方法
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作者 刘博 雷涛 +2 位作者 薛明园 王营博 闵重丹 《无线电工程》 2025年第1期18-27,共10页
金属网栅电磁屏蔽光学窗口是现代战机和电子仪器等设备的关键组件,其制备过程中所使用裂纹模板的裂纹平均宽度对光窗的电磁屏蔽性能至关重要。针对传统手工测量模板平均裂纹宽度效率低和误差大的问题,提出了基于几何形状建模的光窗裂纹... 金属网栅电磁屏蔽光学窗口是现代战机和电子仪器等设备的关键组件,其制备过程中所使用裂纹模板的裂纹平均宽度对光窗的电磁屏蔽性能至关重要。针对传统手工测量模板平均裂纹宽度效率低和误差大的问题,提出了基于几何形状建模的光窗裂纹宽度计算方法。该方法利用深度神经网络分割模型分割样本图像得到二值图像;利用所设计的形态学增强连通分量的图像分析法优化分割结果并得到网格个数、面积和周长表格;通过所设计的几何形状近似宽度算法计算样本图的平均裂纹宽度。基于所提方法,分别对裂纹宽度已知图像和裂纹模板图像开展实验测试,结果表明,所提方法相对于传统手工测量,统计时间缩短约88%,精度提升约5%,具有较高的效率和准确性。 展开更多
关键词 电磁屏蔽光窗 图像分割 深度神经网络 连通分量 几何形状建模 平均宽度测量
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