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On power series statistical convergence and new uniform integrability of double sequences
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作者 Sevda Y■ld■z Kamil Demirci 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期519-532,共14页
In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p... In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings. 展开更多
关键词 power series methods statistical convergence uniform integrability double sequences
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Readjustment of the Paper [J.Kaur and S.S.Bhatia,Integrability and L^1-Convergence of Double Cosine Trigonometric Series,Anal.Theory Appl.,27(1)(2011),pp.32–39.] 被引量:1
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作者 Xhevat Z.Krasniqi 《Analysis in Theory and Applications》 CSCD 2015年第3期299-306,共8页
In this paper, we show that new modified double cosine trigonometric sums introduced in [1] are inappropriate, the class of double sequences Jintroduced there is unusable for such sums and consequently the results obt... In this paper, we show that new modified double cosine trigonometric sums introduced in [1] are inappropriate, the class of double sequences Jintroduced there is unusable for such sums and consequently the results obtained in it are completely incorrect. We here introduce appropriate modified double cosine trigonometric sums making the class Jusable considering a particular double cosine trigonometric series. 展开更多
关键词 L1-convergence double null sequence cosine trigonometric series modified sums
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CONVERGENCE OF DOUBLE WALSH-FOURIER SERIES AND HARDY SPACES 被引量:2
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作者 Ferenc Weisz ( Etvs L. Univrersity, Hungary) 《Analysis in Theory and Applications》 2001年第2期32-44,共13页
It is proved that the maximal operator of the Marczinkiewicz-Fejér meams of a double Walsh-Fourier series is bounded from the two-dimensional dyadic martingale Hardy space H p to L p (2/3<p<∞) and is of we... It is proved that the maximal operator of the Marczinkiewicz-Fejér meams of a double Walsh-Fourier series is bounded from the two-dimensional dyadic martingale Hardy space H p to L p (2/3<p<∞) and is of weak type (1,1). As a consequence we obtain that the Marczinkiewicz-Fejér means of a function f∈L 1 converge a.e. to the function in question. Moreover, we prove that these means are uniformly bounded on H p whenever 2/3<p<∞. Thus, in case f∈H p , the Marczinkiewicz-Fejér means conv f in H p norm. The same results are proved for the conjugate means, too. 展开更多
关键词 HP MATH CONVERGENCE OF double WALSH-FOURIER series AND HARDY SPACES
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APPLICATIONS OF HYPERGEOMETRIC SUMMATION THEOREMS OF KUMMER AND DIXON INVOLVING DOUBLE SERIES 被引量:1
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作者 H.M.SRIVASTAVA M.I.QURESHI +1 位作者 Kaleem A.QURAISHI Ashish ARORA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期619-628,共10页
Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust ... Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust double hypergeometric function. The results presented in this article are based essentially upon the hypergeometric summation theorems of Kummer and Dixon. 展开更多
关键词 Pochhammer's symbol Gamma function series identities hypergeometric re-duction formulas Srivastava-Daoust double and multiple hypergeometric func-tions Legendre's duplication formula Gauss-Legendre multiplication formula Kummer's theorem Dixon's theorem
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Synthesis and crystal structure of a novel double 1:11 series arsenotungstate: [Cu^I(phen)_2]_5H_6[Sm(AsW_(11)O_(39))_2]·6H_2O
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作者 王敬平 王伟 +1 位作者 燕庆霞 牛景杨 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第5期638-642,共5页
A novel double 1:11 series arsenotungstate, [Cu^I(phen)2]5H6[Sm(AsW11O39)2]·6H2O (phen=1, 10-phenanthroline) was synthesized by the hydrothermal method and characterized by elemental analysis, 1R spectra, ... A novel double 1:11 series arsenotungstate, [Cu^I(phen)2]5H6[Sm(AsW11O39)2]·6H2O (phen=1, 10-phenanthroline) was synthesized by the hydrothermal method and characterized by elemental analysis, 1R spectra, and single-crystal X-ray diffraction. The title compound was monoclinic, space group P2 1/c, a=3.75710(2) nm, b=1.39776(8) nm, c=-3.33735(18) nm, β=96.967(10)°, V=17.3969(17) nm^3, Z=4. Single crystal X-ray structural analyses revealed that the dimeric polyanion, [SmAs2W22O78]^1-, consisted of one central Sm^3+ ion and two tetradentate heteropoly ligands [ASW11O39]^7-. The Sm^3+ ion and two tetradentate defective [AsW11O39]^7- anions were joined together by the sharing of four oxygen atoms from each heteropoly ligand. The bond valence sum (BVS) calculations of the title compound suggested that all four Cu atoms were in the +1 oxidation sate. 展开更多
关键词 hydrothermal synthesis crystal structure ARSENOTUNGSTATE double 1:11 series rare earths
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Estimation of Winds at Different Isobaric Levels Based on the Observed Winds at 850 hPa Level Using Double Fourier Series
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作者 S. N. Bavadekar (1) R. M. Khaladkar (1) 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1994年第3期327-334,共8页
A technique based on the double Fourier series is developed to estimate the winds at different isobaric levels forthe limited area domain, 35°E to 140°E and 30°S to 40°N, using the observed winds a... A technique based on the double Fourier series is developed to estimate the winds at different isobaric levels forthe limited area domain, 35°E to 140°E and 30°S to 40°N, using the observed winds at 850 hPa lcvcl for the month ofJune. For this purpose the wind field at a level under consideration is taken in the ratio form with that of 850 hPa level and the coefficients of the double Fouricr series are computed. These coefficients are subsequently used to computethe winds which are compared with the actual winds. The results of the double Fourier series technique are comparedwith those of the polynomial surface fitting method developed by Bavadekar and Khaladkar (1 992). The technique isalso applied for the daily wind data of 11. June, 1979 and the validation of the technique is tested for a few radiosondestations of india. The computed winds for these radiosonde stations arc quite close to observed winds. 展开更多
关键词 double Fourier series Objective analysis Cloud motion vectors Numerical weather prediction Polynomial surface fitting
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APPROXIMATION PROPERTIES OF (C, α) MEANS OF DOUBLE WALSH-FOURIER SERIES
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作者 Ushangi Goginava 《Analysis in Theory and Applications》 2004年第1期77-98,共22页
We study the rate of Lp approximation by Cesaro means of the quadratic partial sums of double Walsh-Fourier series of functions from Lp.
关键词 Cesaro means double wallsh-Fourier series
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Fault Locator Using Two-end Unsynchronized Measurements for UHV Series Compensated Double-circuit Lines
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作者 M. Fulczyk P. Balcerek +2 位作者 J. Izykowski E. Rosolowski M. M. Saha 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2523-2529,共7页
An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutin... An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutines,designated for locating faults on particular line sections,and additionally the procedure for selecting the valid subroutine.The subroutines are formulated with use of the generalized fault loop model and the distributed parameter line model is applied.Performed ATP-EMTP based evaluation has shown the validity of the derived fault location algorithm and its high accuracy. 展开更多
关键词 两端非同步测量法 串联补偿 线路故障 定位仪 ATP-EMTP
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Constitutive equations of 1060 pure aluminum based on modified double multiple nonlinear regression model 被引量:6
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作者 李攀 李付国 +2 位作者 曹俊 马新凯 李景辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1079-1095,共17页
In order to study the work-ability and establish the optimum hot formation processing parameters for industrial 1060 pure aluminum, the compressive deformation behavior of pure aluminum was investigated at temperature... In order to study the work-ability and establish the optimum hot formation processing parameters for industrial 1060 pure aluminum, the compressive deformation behavior of pure aluminum was investigated at temperatures of 523?823 K and strain rates of 0.005?10 s?1 on a Gleeble?1500 thermo-simulation machine. The influence rule of processing parameters (strain, strain rate and temperature) on flow stress of pure aluminum was investigated. Nine analysis factors consisting of material parameters and according weights were optimized. Then, the constitutive equations of multilevel series rules, multilevel parallel rules and multilevel series &parallel rules were established. The correlation coefficients (R) are 0.992, 0.988 and 0.990, respectively, and the average absolute relative errors (AAREs) are 6.77%, 8.70% and 7.63%, respectively, which proves that the constitutive equations of multilevel series rules can predict the flow stress of pure aluminum with good correlation and precision. 展开更多
关键词 1060 pure aluminum modified DMNR(double multiple nonlinear regression) constitutive equation flow behaviour multilevel series rules multilevel parallel rules multilevel series & parallel rules
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Research on the Sub-synchronous Oscillation in Wind Power Connected to Series Compensated Power System and its Influencing Factors 被引量:3
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作者 Chao Gao Hui Liu +2 位作者 Hao Jiang Yunhong Li Xisheng Tang 《CES Transactions on Electrical Machines and Systems》 2017年第3期334-340,共7页
When wind farms,which is based on double fed induction generator(DFIG),are connected to the series compensation power system,the phenomenon of sub-synchronous oscillation(SSO)may occur.In order to study the sub-synchr... When wind farms,which is based on double fed induction generator(DFIG),are connected to the series compensation power system,the phenomenon of sub-synchronous oscillation(SSO)may occur.In order to study the sub-synchronous oscillation in wind power connected to series compensated power system and its influencing factors,we used RT-LAB to establish a simulation model concerning wind power connected to series-compensation power system.This model take a wind power connected to series compensation power system in north China as prototype.All influence factors of wind power SSO are simulated and analyzed by using time domain analysis method.The simulation results show that the effects of wind speed,series compensation degree and proportional control coefficient of rotor side converter(RSC)are most obvious. 展开更多
关键词 double fed induction generator influence factors interaction of SSO sub-synchronous oscillation series compensation
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Domain of Euler Mean in the Space of Absolutely p-Summable Double Sequences with 0
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作者 Medine Yesilkayagil Feyzi Basar 《Analysis in Theory and Applications》 CSCD 2018年第3期241-252,共12页
In this study, as the domain of four dimensional Euler mean E(r,s) of orders r,sin the space L_p for 0 < p < 1, we examine the double sequence space ε_p^(r,s) and some properties of four dimensional Euler mean.... In this study, as the domain of four dimensional Euler mean E(r,s) of orders r,sin the space L_p for 0 < p < 1, we examine the double sequence space ε_p^(r,s) and some properties of four dimensional Euler mean. We determine the α-and β(bp)-duals of the space εp r,s, and characterize the classes(ε_p^(r,s):M_u),(ε_p^(r,s):C_(bp)) and(ε_p^(r,s):L_q) of four dimensional matrix transformations, where 1 ≤q < ∞. Finally, we shortly emphasize on the Euler spaces of single and double sequences, and note some further suggestions. 展开更多
关键词 Summability theory double sequences double series alpha- beta- and gammaduals matrix domain of 4-dimensional matrices matrix transformations
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Double sampling derivatives and truncation error estimates
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作者 Rashad M.Asharabi Aisha M.Al-Hayzea 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第2期209-224,共16页
This paper investigates double sampling series derivatives for bivariate functions defined on R2 that are in the Bernstein space. For this sampling series, we estimate some of the pointwise and uniform bounds when the... This paper investigates double sampling series derivatives for bivariate functions defined on R2 that are in the Bernstein space. For this sampling series, we estimate some of the pointwise and uniform bounds when the function satisfies some decay conditions. The truncated series of this formula allow us to approximate any order of partial derivatives for function from Bernstein space using only a finite number of samples from the function itself. This sampling formula will be useful in the approximation theory and its applications, especially after having the truncation error well-established. Examples with tables and figures are given at the end of the paper to illustrate the advantages of this formula. 展开更多
关键词 double sampling series truncation error bounds convergence rate
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On a Linear Summation Problem of the Double Fourier Series
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作者 XuChunning HeJiaxing 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 1998年第2期76-78,共3页
It this paper we construct a double Fourier series with a new linear summation factor, for the arbitrary continuous periodic function f(x,y)with period 2л, it converges to the function(fx,y) uniformly on total opl... It this paper we construct a double Fourier series with a new linear summation factor, for the arbitrary continuous periodic function f(x,y)with period 2л, it converges to the function(fx,y) uniformly on total oplane,and its convergence order is the best one. 展开更多
关键词 double Fourier series Summation factor convergence order
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一种基于改进双二极管脉波倍增电路的串联型24脉波整流器
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作者 王景芳 赵晨 +3 位作者 姚绪梁 于天龙 刘腾 陈启明 《中国电机工程学报》 EI CSCD 北大核心 2024年第12期4878-4890,I0023,共14页
为了在不增加串联型12脉波整流器中移相变压器复杂度的前提下,有效地抑制整流器的输入电流谐波,该文提出一种基于改进双二极管脉波倍增电路(improved dual-diode pulse-doubling circuit,IDPC)的串联型24脉波整流器。提出的IDPC被安装... 为了在不增加串联型12脉波整流器中移相变压器复杂度的前提下,有效地抑制整流器的输入电流谐波,该文提出一种基于改进双二极管脉波倍增电路(improved dual-diode pulse-doubling circuit,IDPC)的串联型24脉波整流器。提出的IDPC被安装在整流器的直流侧并由单相自耦变压器、平衡电抗器、2个电容器和2个辅助二极管组成。IDPC中的辅助二极管根据整流器中2个三相整流桥的输出电压和单相自耦变压器绕组电压之间的关系交替导通,使IDPC周期性工作在3种模态下,然后根据交直流侧电压和电流关系将整流器的脉波数从12增加到24,使得输入电流的THD减小为原来的二分之一,有效地抑制输入电流谐波。因IDPC中磁性器件的总容量仅为输出功率的2.35%,辅助二极管的电流应力仅为输出电流的6.8%,提出的方案具有电路结构简单、容量小,成本低和导通损耗小的优点。与类似结构相比,提出的整流器在中高压工业场合具有更好的应用前景。搭建了一台输出功率为1 kW的实验样机,实验结果验证了理论分析的有效性和正确性。 展开更多
关键词 串联24脉波整流器 电流谐波 脉波倍增 双辅助二极管
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黄河水沙监测数据分析模型
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作者 陈瑶 徐萌 +1 位作者 金成涛 王积建 《数学建模及其应用》 2024年第2期100-113,共14页
为研究黄河小浪底水库下游某水文站水沙通量的变化规律和“调水调沙”效果,以2016-2022年水位、水流量与含沙量的实际监测数据为依据,估算出年均径流量325亿立方米,年均排沙量2亿吨.分别使用双对数回归分析、M-K检验、小波分析、R/S分... 为研究黄河小浪底水库下游某水文站水沙通量的变化规律和“调水调沙”效果,以2016-2022年水位、水流量与含沙量的实际监测数据为依据,估算出年均径流量325亿立方米,年均排沙量2亿吨.分别使用双对数回归分析、M-K检验、小波分析、R/S分析对水沙通量的敏感性、突变性、周期性、趋势性进行了分析,得出结论:水位每增加1%,含沙量就增加37.63%,含沙量关于水位非常敏感;水沙通量均在2018年3月发生了突变;水沙通量均以18月为主周期振荡;水通量、沙通量在未来2年分别是增长趋势和下降趋势.使用傅里叶级数叠加线性函数预测未来2年的水沙通量,并建立了0-1规划模型对今后2年的监测方案进行了优化.通过比较“调水调沙”前后水沙通量、河底高程的变化,证明了“调水调沙”效果非常显著. 展开更多
关键词 双对数回归 M-K检验 小波分析 R/S分析 傅里叶级数 0-1规划
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基于动态神经网络NARX时间序列的双排桩基坑变形预测 被引量:1
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作者 侯福昌 曾家俊 +2 位作者 江杰 李结全 范懿文 《广西大学学报(自然科学版)》 CAS 北大核心 2024年第1期49-59,共11页
针对目前基于含基本假设或经验公式的传统土力学计算方法,不能有效地反映具有多因素交叉性以及时空性的基坑变形规律,而监测数据时间序列能够真实地表现基坑土体变形的演变,以南宁市亭洪路72号河南水厂住宅小区危旧房改造项目双排桩基... 针对目前基于含基本假设或经验公式的传统土力学计算方法,不能有效地反映具有多因素交叉性以及时空性的基坑变形规律,而监测数据时间序列能够真实地表现基坑土体变形的演变,以南宁市亭洪路72号河南水厂住宅小区危旧房改造项目双排桩基坑工程为依托,考虑开挖深度和土体暴露时间这2个因素对监测时间序列的影响,提出一种带有外部输入的非线性自回归(NARX)动态神经网络时间序列模型,多方位预测关键断面重要测点的竖向位移和水平位移。结果表明:预测值和实际监测数据的变化趋势具有较好的一致性,且竖向位移预测值与实际监测值的预测残差小于1.0 mm,水平位移预测残差小于0.3 mm。该模型预测效果良好,同时验证了此模型应用于双排桩基坑变形动态分析的可行性。 展开更多
关键词 动态神经网络 时间序列 预测模型 双排桩 基坑变形
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双罐串联连续血液净化对慢性肾衰竭尿毒症患者血清可溶性转铁蛋白受体和人巨噬细胞趋化蛋白-1水平及生存质量的影响 被引量:1
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作者 祖可拉阿依•木依布拉 何帆 杨文君 《中国医学装备》 2024年第5期112-117,共6页
目的:探讨双罐串联连续血液净化(CRRT)对慢性肾衰竭尿毒症患者血清可溶性转铁蛋白受体(sTfR)和人巨噬细胞趋化蛋白-1(MCP-1)水平及生存质量的影响。方法:选择2022年4月至2023年4月新疆医科大学第一附属医院行血液透析治疗的96例慢性肾... 目的:探讨双罐串联连续血液净化(CRRT)对慢性肾衰竭尿毒症患者血清可溶性转铁蛋白受体(sTfR)和人巨噬细胞趋化蛋白-1(MCP-1)水平及生存质量的影响。方法:选择2022年4月至2023年4月新疆医科大学第一附属医院行血液透析治疗的96例慢性肾衰竭尿毒症患者,随机分为单罐组(CRRT连续血液净化单个灌流器)和双罐串联组(CRRT连续血液净化2个灌流器串联),每组48例。分别于治疗前,治疗后2个月、半年及1年时检测两组患者血清sTfR和MCP-1水平,判断其治疗后皮肤瘙痒缓解程度;分别于治疗前及治疗后72h记录两组白细胞水平、急性生理与慢性健康量表(APACHEⅡ)评分情况。采用中文版欧洲五维量表(CEQ-5D-3L)、视觉模拟量表(VAS)评分,评估两组患者治疗前后生命质量。结果:两组治疗前血清sTfR水平比较差异无统计学意义(P>0.05)。治疗后2个月、半年及1年各时间点,双罐串联组血清sTfR水平均低于单罐组,差异有统计学意义(t=5.089、18.410、41.306,P<0.05);两组治疗前血清MCP-1水平比较,差异无统计学意义(P>0.05)。治疗后2个月、半年及1年各时间点,双罐串联组血清MCP-1水平均低于单罐组,差异有统计学意义(t=8.554、8.019、10.744,P<0.05);两组治疗后原有皮肤瘙痒程度均有所改善,但单罐组缓解程度明显低于双罐串联组,差异有统计学意义(x^(2)=8.540,P<0.05);两组治疗前白细胞、APACHEⅡ评分比较,差异无统计学意义(P>0.05),治疗后72h白细胞、APACHEⅡ评分均降低,且双罐串联组改善程度均优于单罐组,差异有统计学意义(t=5.549、14.781,P<0.05);两组治疗前血清CEQ-5D-3L评分比较,差异无统计学意义(P>0.05)。治疗后2个月、半年及1年各时间点,双罐串联组健康描述系统标准总分均低于单罐组,VAS评分高于单罐组,差异有统计学意义(t健康描述系统标准总分=4.744、5.103、9.418,tVAS评分=3.375、2.866、3.126,P<0.05)。结论:双罐串联连续血液净化可有效降低慢性肾衰竭尿毒症患者血清sTfR,MCP-1水平,缓解皮肤瘙痒程度,提高生存质量,同时还能有效降低白细胞水平,改善APACHEⅡ评分和血常规。 展开更多
关键词 双罐串联 连续血液净化(CRRT) 慢性肾衰竭 尿毒症 血清可溶性转铁蛋白受体(sTfR) 人巨噬细胞趋化蛋白-1(MCP-1) 生存质量
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含夹层流体的双板主、被动控制理论分析和试验研究
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作者 文仕天 陈美霞 赵应龙 《噪声与振动控制》 CSCD 北大核心 2024年第3期35-42,共8页
为了对含夹层流体的双板结构的振动进行控制,基于改进的傅里叶级数法对此双板结构进行理论建模,采取等效方法考虑涂敷阻尼层的影响,并运用有限元方法验证理论模型的正确性。同时介绍FxLMS算法并将其运用于双板的主动控制中,以前述理论... 为了对含夹层流体的双板结构的振动进行控制,基于改进的傅里叶级数法对此双板结构进行理论建模,采取等效方法考虑涂敷阻尼层的影响,并运用有限元方法验证理论模型的正确性。同时介绍FxLMS算法并将其运用于双板的主动控制中,以前述理论方法为基础,得到各通道的传递函数,并基于MATLAB进行算法仿真,取得较好控制效果,可为算法的控制效果验证提供参考。对双板的振动进行控制试验,对比控制前后双板振动加速度级,发现敷设阻尼层较为明显减弱中高频振动,在135Hz频率点处主动控制单通道的控制效果良好,主、被动一体化控制前后下板的振动加速度总级(10~3000Hz)相比降低6.61dB,验证了控制措施的有效性。 展开更多
关键词 振动与波 改进的傅里叶级数法 双板结构 被动控制 主动控制 Filter-xLMS算法
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横坡段桥梁双桩双柱式结构受力特征与解析模型
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作者 王佳佳 陈效坤 +3 位作者 肖莉丽 陈星潮 陈浩 李枝强 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第3期1092-1106,共15页
山区桥梁基础不可避免地建立在陡坡上,不稳定斜坡变形或破坏将会对上覆桥跨结构安全造成严重威胁,亟需研究高效、可靠的力学模型。首先,对横坡段桥梁双桩双柱式结构划分不同特征段,分析其受力特性;其次,考虑桩土相互作用和桩顶变形协调... 山区桥梁基础不可避免地建立在陡坡上,不稳定斜坡变形或破坏将会对上覆桥跨结构安全造成严重威胁,亟需研究高效、可靠的力学模型。首先,对横坡段桥梁双桩双柱式结构划分不同特征段,分析其受力特性;其次,考虑桩土相互作用和桩顶变形协调关系并引入边界条件,建立适用于横坡段桥梁双桩双柱式结构内力及位移的简化模型;第三,综合考虑P-Δ效应及盖/系梁对桩柱受力影响,引入相邻特征段满足的连续条件(即位移、转角、剪力及弯矩连续),建立挠曲微分方程并以MATLAB为平台编制相应计算程序,提出横坡段桥梁双桩双柱式结构基础内力及位移的幂级数解;最后,将模型结果与有限元计算结果对比,验证模型的可靠性。研究结果表明:本文提出的模型将桥墩与桩基础视为整体,对于多道系梁的结构分析该模型同样适用;模型考虑了横向联系对两桩轴向力和弯矩的分配,可获取横向联系中的横向力;模型不需要假设自由段剪力和迭代计算。随着剩余下滑力增大,结构各特征段前后桩位移和弯矩明显增加;横向联系对桩基位移及内力进行了重新分配,有较强的约束作用,能够较好地改善前后桩受力与变形情况。 展开更多
关键词 横坡段桥梁 双桩双柱结构 受力特征 幂级数解 有限元分析
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颗粒参数对倾斜串联弯管冲蚀磨损的影响
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作者 谢晓刚 石喜 +1 位作者 谭春彬 田云霞 《科学技术与工程》 北大核心 2024年第19期8259-8268,共10页
为研究颗粒参数对倾斜串联弯管冲蚀磨损的影响,以倾斜度为60°的S形串联弯管为研究对象,通过离散相模型(DPM)分析颗粒流速、颗粒直径、颗粒质量流率等颗粒参数对串联弯管冲蚀速率、主要冲蚀区域和冲蚀形貌的影响规律,并对比两弯管... 为研究颗粒参数对倾斜串联弯管冲蚀磨损的影响,以倾斜度为60°的S形串联弯管为研究对象,通过离散相模型(DPM)分析颗粒流速、颗粒直径、颗粒质量流率等颗粒参数对串联弯管冲蚀速率、主要冲蚀区域和冲蚀形貌的影响规律,并对比两弯管的冲蚀磨损。结果表明:颗粒流速对弯管的冲蚀磨损影响最大,呈指数关系;颗粒直径对于弯管2的影响大于弯管1,弯管2的磨损随直径的增加呈先增后减的趋势,当颗粒直径增加到250μm以后,弯管1的冲蚀磨损大于弯管2;颗粒质量流速对弯管的冲蚀磨损影响较小,随着颗粒质量流速的增加,两弯管冲蚀速率的增速逐渐缓慢。可见为增加弯管使用寿命,减少弯管的冲蚀磨损,使用时应注意控制流体流速。 展开更多
关键词 倾斜度 串联弯管 DPM 颗粒参数 冲蚀磨损
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