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GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N) 被引量:1
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作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUNDEDNEss unit ball
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The Impact and Intervention of Handheld Tai Chi Water-Resistance Fitness Ball on Middle-Aged and Elderly Patients with Parkinson’s Disease
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作者 He Huang 《Health》 2024年第4期319-349,共31页
Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionna... Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionnaire on exercise compliance for patients with Parkinson’s disease was developed, and its reliability and validity were tested. Then, a survey was conducted to investigate the current status of exercise compliance among Parkinson’s disease patients, including general information, scoring status, and single and multiple factor analyses of influencing factors [1]. The results of the study show that through qualitative research, the dimensions and item pools of the questionnaire were initially constructed, and the reliability analysis of the questionnaire was conducted through Delphi expert consultation, with favorable results in terms of its reliability and validity [2]. Regarding the current status of exercise compliance among Parkinson’s disease patients, the study found that the level of exercise compliance needs improvement, and there are significant differences in exercise compliance levels among patients under different circumstances. Finally, the research results were discussed and conclusions were drawn. The innovation of this study lies in the development of a questionnaire on exercise compliance for patients with Parkinson’s disease and the preliminary qualitative research and Delphi expert consultation conducted on it, providing new ideas and methods for the study of exercise compliance. However, the study also has limitations as it did not examine the effects of other interventions on Parkinson’s disease, so further research should be conducted [3]. 展开更多
关键词 Parkinson’s Disease Exercise Compliance Tai Chi Water Resistance Fitness ball Influencing Factors Intervention Effectiveness
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AN INTEGRAL ESTIMATE AND THE EQUIVALENT NORMS ON F(p, q, s, k) SPACES IN THE UNIT BALL 被引量:8
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作者 张学军 黎深莲 +1 位作者 尚清丽 郭雨婷 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1861-1880,共20页
In this article, the authors give a typical integral's bidirectional estimates for allcases. At the same time, several equivalent characterizations on the F(p, q, s, k) space in theunit ball of Cn are given.
关键词 F(p Q s k) space integral estimate equivalent norm unit ball
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s space Bers-type space weighted composition operator unit ball
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Convergence ball and error analysis of Ostrowski-Traub’s method 被引量:1
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作者 BI Wei-hong WU Qing-biao REN Hong-min 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期374-378,共5页
Under the hypotheses that the second-order and third-order derivatives of a function are bounded, an estimate of the radius of the convergence ball of Ostrowski-Traub's method is obtained. An error analysis is given ... Under the hypotheses that the second-order and third-order derivatives of a function are bounded, an estimate of the radius of the convergence ball of Ostrowski-Traub's method is obtained. An error analysis is given which matches the convergence order of the method. Finally, two examples are provided to show applications of our theorem. 展开更多
关键词 Ostrowski-Traub's method nonlinear equation convergence ball estimate of radius error analysis
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Class of Charged Fluid Balls in General Relativity 被引量:2
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作者 A. Sah Prakash Chandra 《International Journal of Astronomy and Astrophysics》 2016年第4期494-511,共18页
In the present study, we have obtained a new analytical solution of combined Einstein-Maxwell field equations describing the interior field of a ball having static spherically symmetric isotropic charged flu... In the present study, we have obtained a new analytical solution of combined Einstein-Maxwell field equations describing the interior field of a ball having static spherically symmetric isotropic charged fluid within it. The charge and electric field intensity are zero at the center and monotonically increasing towards the boundary of the fluid ball. Besides these, adiabatic index is also increasing towards the boundary and becomes infinite on it. All other physical quantities such as pressure, density, adiabatic speed of sound, charge density, adiabatic index are monotonically decreasing towards the surface. Causality condition is obeyed at the center of ball. In the limiting case of vanishingly small charge, the solution degenerates into Schwarzchild uniform density solution for electrically neutral fluid. The solution joins smoothly to the Reissner-Nordstrom solution over the boundary. We have constructed a neutron star model by assuming the surface density . The mass of the neutron star comes  with radius 14.574 km. 展开更多
关键词 Exact solution Einstein’s Field Equations Charged Fluid ball Compact star General Relativity
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GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——
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作者 周晋康 《苏州大学学报(工科版)》 CAS 1992年第S2期27-34,共8页
By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we... By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points. 展开更多
关键词 balls POINT centering - POINT CURVE and CIRCLING CURVE four IsPs Coupler curves based on balls Points
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TCL——King Brand Colour TV Rivals the World's Famous Brands
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《China's Foreign Trade》 1996年第2期44-44,共1页
World famous colour TVs,such asSony,National and Toshiba,usedto monopolize China’s large-screencolour TV market.But recently the KingBrand colour TV made by the TCL ElectronicsGroup has begun to challenge them.In1995... World famous colour TVs,such asSony,National and Toshiba,usedto monopolize China’s large-screencolour TV market.But recently the KingBrand colour TV made by the TCL ElectronicsGroup has begun to challenge them.In1995,the TCL King Brand colour TV notonly ranked first for its sales volume on theChinese market among the domestically-produced TVs of its kind,but also 展开更多
关键词 TCL King Brand Colour TV rivals the World’s Famous Brands TV World
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NUMERICAL STUDY OF DIFFERENTIAL TORQUE-PRODUCING JETS IN A FLOATED-BALL INERTIAL PLATFORM
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作者 章光华 朱雅萍 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1998年第1期1-9,共9页
This paper presents a numerical study of the flow field caused by torque-producing jets in a floated-ball inertial guiding system. The basic flow element studied is the flow in a triangular region of octant sphere sur... This paper presents a numerical study of the flow field caused by torque-producing jets in a floated-ball inertial guiding system. The basic flow element studied is the flow in a triangular region of octant sphere surface confined by the two sphere surfaces and the three attitude-driver bands normal to each other. The results show the flow patterns of torque-producing jets and the relations between the effective driving torques and the flow rates under several typical working conditions. The working performances of two kinds of differential torque-producing jets are analyzed and compared. The second kind of differential torque-producing jets, which is first proposed in this paper, has the prominent merit, i.e., the regulation of the three components of driving torque can be realized by non-interference adjustment, so that the three components of angular displacement can be controlled independently. 展开更多
关键词 floated-ball inertial platform differential torque-producing jets N-s equation Reynolds equation
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一种球头铣刀“S”形刃口曲线的数学建模方法 被引量:4
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作者 庞思勤 乔小峰 +1 位作者 王西彬 彭松 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第5期44-49,共6页
为了简化球头铣刀'S'形刃口的数学模型,推导两个空间平面与球面相交而成的复合型刃口曲线方程,提出并应用了'单球法'和'双球法'两种数学建模方法,并推导了球头铣刀球面部分平面刃口曲线偏转角和螺旋角的数学表... 为了简化球头铣刀'S'形刃口的数学模型,推导两个空间平面与球面相交而成的复合型刃口曲线方程,提出并应用了'单球法'和'双球法'两种数学建模方法,并推导了球头铣刀球面部分平面刃口曲线偏转角和螺旋角的数学表达式.结果表明:偏转角和螺旋角两者相等,可以简化球面部分平面刃口曲线的数学模型,既降低了平面刀刃曲线的推导过程的复杂性,同时又为两个或多个空间平面与球头铣刀球面部分相交而成的复合型刃口曲线方程的建模提供了一种有效方法. 展开更多
关键词 球头铣刀 s”形刃口曲线 刀刃曲线 数学模型
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“S”形刃球头立铣刀的研究(Ⅲ)──刃磨参数分析 被引量:4
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作者 胡思节 廖钢 +1 位作者 易德明 杨受章 《湖南大学学报(自然科学版)》 EI CAS CSCD 1996年第6期71-77,共7页
在已建立数学模型的基础上,根据建模时的刃磨方法,推导了刃磨参数与结构参数及设计参数的关系式;分析了刃磨参数的变化对设计参数的影响.对“S”
关键词 球头立铣刀 刃磨参数 s形刃 铣刀
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基于T-S模糊模型的球磨机负荷控制系统 被引量:10
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作者 刘蓉 吕震中 《电力自动化设备》 EI CSCD 北大核心 2007年第3期17-20,共4页
球磨机负荷控制系统通过调节给煤机的转速控制存煤量在给定值附近。针对其存在非线性、参数时变和大延迟等难以控制的特性,提出基于T-S模糊模型的预测函数控制新方法。用T-S模糊模型描述对象的非线性动态特性,根据模糊规则将非线性模型... 球磨机负荷控制系统通过调节给煤机的转速控制存煤量在给定值附近。针对其存在非线性、参数时变和大延迟等难以控制的特性,提出基于T-S模糊模型的预测函数控制新方法。用T-S模糊模型描述对象的非线性动态特性,根据模糊规则将非线性模型分解为若干个局部线性模型,并依据球磨机负荷对象的特性,将线性模型简化为一阶纯滞后环节。对辨识后得到的每个局部线性模型采用预测函数控制算法。仿真研究结果表明:系统响应速度变快、超调量较小,表现出较好的动态响应特性,同时还避免了PID控制器3个参数难以整定的困难。 展开更多
关键词 球磨机 T—s模糊模型 预测函数控制 辨识
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Gleason问题在多复变F(p,q,s)空间上的可解性 被引量:4
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作者 张学军 刘亚玲 肖建斌 《数学年刊(A辑)》 CSCD 北大核心 2010年第2期221-228,共8页
在0<p<∞,0≤s<∞,max{-n-1,-s-1}<q<∞的条件下,证明了Gleason问题在C^n中以单位球为支撑集的一般函数空间F(p,q,s)上是可解的.
关键词 GLEAsON问题 F(P Q s)空间 单位球
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S形刃球头立铣刀的数学模型 被引量:4
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作者 蔺小军 侯忠滨 何琼儒 《工具技术》 北大核心 2004年第1期40-42,共3页
建立了S形刃球头立铣刀内前刀面、外前刀面及螺旋后刀面、平面后刀面的数学模型。该模型的建立为球头立铣刀刃磨参数选择及刃磨装置设计具有重要的作用。
关键词 s形刃 球头立铣刀 数学模型 刃磨
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板球系统的T-S模糊多变量控制方案 被引量:6
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作者 滕树杰 张乃尧 范醒哲 《信息与控制》 CSCD 北大核心 2002年第3期268-271,共4页
板球系统是一个典型的多变量、非线性控制对象 ,它是杆球系统的扩展 ,适合用以检验各种控制方案 .本文介绍了板球系统及其数学模型 ,就轨迹跟踪问题提出了基于 T- S模型的模糊多变量控制方案 ,并验证了这种控制方案能使系统全局渐进稳... 板球系统是一个典型的多变量、非线性控制对象 ,它是杆球系统的扩展 ,适合用以检验各种控制方案 .本文介绍了板球系统及其数学模型 ,就轨迹跟踪问题提出了基于 T- S模型的模糊多变量控制方案 ,并验证了这种控制方案能使系统全局渐进稳定 .仿真实验结果表明本文所采用的控制方案明显优于传统的 PD控制方案 . 展开更多
关键词 板球系统 轨迹跟踪 模糊多变量控制 T-s模型
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程控球阀在S Zorb装置上的应用 被引量:13
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作者 张昆 毛文华 沈安伟 《炼油技术与工程》 CAS 2013年第10期22-25,共4页
闭锁料斗程控耐磨球阀故障频繁已成为S Zorb装置生产的共性问题,其使用工况苛刻,设计要求较高。介绍了该类球阀的结构特征,分析了装置运行中球阀故障的原因。以XV2408程控球阀为例,得出在工艺操作压力变化下,球阀反向受压迫使碟簧发生形... 闭锁料斗程控耐磨球阀故障频繁已成为S Zorb装置生产的共性问题,其使用工况苛刻,设计要求较高。介绍了该类球阀的结构特征,分析了装置运行中球阀故障的原因。以XV2408程控球阀为例,得出在工艺操作压力变化下,球阀反向受压迫使碟簧发生形变,吸附剂颗粒有机会进入阀球与阀座形成硬质粘附物是球阀故障的主要原因。分别从安装、操作及设备管理方面提出延长球阀使用寿命的方法,提出了安装方向的判别原则,减少输送介质带液的手段,开工时的注意事项等。 展开更多
关键词 s Zorb吸附脱硫技术 闭锁料斗 程控耐磨球阀
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基于FKCM的球磨机系统T-S模糊建模方法 被引量:5
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作者 王恒 贾民平 +2 位作者 许飞云 陈左亮 谢超 《系统仿真学报》 CAS CSCD 北大核心 2009年第2期530-533,共4页
针对传统的描述热工过程动态数学模型的方法难以建立非线性模型的缺点,提出了一种基于模糊核聚类的球磨机系统T-S模糊建模算法。该算法首先通过灰色关系法确定模型输入变量,利用FKCM聚类算法对输入空间进行模糊划分,确定T-S模型的前件... 针对传统的描述热工过程动态数学模型的方法难以建立非线性模型的缺点,提出了一种基于模糊核聚类的球磨机系统T-S模糊建模算法。该算法首先通过灰色关系法确定模型输入变量,利用FKCM聚类算法对输入空间进行模糊划分,确定T-S模型的前件结构和前件参数;进而利用最小二乘算法确定模糊规则的后件参数。最后,利用数字仿真数据对球磨机系统进行模糊建模,建模结果表明该算法简单﹑实用,模型能够精确地描述过程的非线性。 展开更多
关键词 球磨机 T-s模糊模型 模糊核聚类 灰色关联度分析
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“S”形刃球头立铣刀的磨削成形刀位轨迹研究 被引量:5
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作者 吕颖 姚斌 +3 位作者 陈站 代平 滕伟斌 罗琪 《工具技术》 北大核心 2015年第10期24-27,共4页
基于球头立铣刀"S"形刀刃曲线完成了球头前刀面和后刀面的砂轮刀位轨迹计算,根据CNC工具磨床转换为机床的运动参数,结合计算机语言及切削仿真验证了数学模型的正确性,为"S"形刃球头立铣刀的磨削成形提供了理论依据。
关键词 s”形刃 球头立铣刀 磨削成形 刀位轨迹
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S形刃口球头铣刀加工的误差分析 被引量:3
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作者 汪云涛 鲍青山 唐余勇 《制造技术与机床》 CSCD 北大核心 2002年第8期34-36,共3页
文章探讨了研制S形球头铣刀的意义 ,在加工刀具的前刀面和后刀面的数学模型基础上 ,研究了误差数学模型 ,并探讨了工业实现的可行性机构 ,给出了相关的数学公式和加工数据 ,最后给出加工可行的各参数误差范围 ,得出结论用 2轴可以实现... 文章探讨了研制S形球头铣刀的意义 ,在加工刀具的前刀面和后刀面的数学模型基础上 ,研究了误差数学模型 ,并探讨了工业实现的可行性机构 ,给出了相关的数学公式和加工数据 ,最后给出加工可行的各参数误差范围 ,得出结论用 2轴可以实现在传统上用 4轴数控机床才能加工的S形球头铣刀 ,并可以保证加工精度。 展开更多
关键词 s形刃口 球头铣刀 数学模型 误差分析
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S Zorb装置关键设备运行分析 被引量:10
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作者 李辉 《石油炼制与化工》 CAS CSCD 北大核心 2012年第9期81-85,共5页
分析S Zorb装置的两类关键设备——反应器过滤器和金属密封球阀在运行中存在的问题。通过降低吸附剂细粉含量,或采用其它辅助手段降低到达过滤器表面的固体颗粒数量,可以有效降低过滤器的负荷;改善和优化反吹参数,保证反吹压力和避免反... 分析S Zorb装置的两类关键设备——反应器过滤器和金属密封球阀在运行中存在的问题。通过降低吸附剂细粉含量,或采用其它辅助手段降低到达过滤器表面的固体颗粒数量,可以有效降低过滤器的负荷;改善和优化反吹参数,保证反吹压力和避免反吹阀门内漏是过滤器再生的关键。安装时注意球阀密封的方向,保证管道内清洁,做好工艺调整,避免程序的中断,加强阀门在线和离线检验,及时修理有故障的阀门以及储备一定数量的备用阀门是保证金属密封球阀正常运行的主要对策。 展开更多
关键词 s ZORB 过滤器 金属密封球阀
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