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Clinical Observation on 100 Cases of Postoperative Pain of Anal-Intestinal Diseases Treated with Vitamine K Blocking at Changqiang Point
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作者 王为 张景云 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2002年第4期280-281,共2页
  Since the latter half of 1996, we have used vitamine K blocking at Changqiang (GV 1) for relieving the postoperative pain of anal fissure with satisfactory results. A report follows.……
关键词 In Clinical Observation on 100 Cases of Postoperative Pain of Anal-Intestinal Diseases Treated with Vitamine K blocking at Changqiang point
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Clinical Observation on Brachial Plexus Block with “One Injection Two Points” Method Guiding by Ultrasound
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作者 Huang Qiang Cai Lingling +10 位作者 Shi Wenjing Fang Zhiyuan Wu Meichao Sun Zhaohui Sun Yulan Li Yong Lu Shangting Xu Hui HWANG DONGWOOK Wang Hongliang Zhang Tao 《World Journal of Integrated Traditional and Western Medicine》 2017年第1期14-17,共4页
OBJECTIVE: To compare the clinical effect of brachial plexus block with "One Injection Two Points" guided under ultrasound and the conventional method guiding by ultrasound. METHODS: 70 patients were randomi... OBJECTIVE: To compare the clinical effect of brachial plexus block with "One Injection Two Points" guided under ultrasound and the conventional method guiding by ultrasound. METHODS: 70 patients were randomized evenly into 2 groups, with 35 patients in each group, while the Experiment Group(Group B) received One Injection Two Points" method, the Control Group(Group A) received the conventional method.The nerve block every 5 s, the success rate of anesthesia, the dosage of local anesthetics, second remedial anesthesia, adverse reactions, etc.were recorded. RESULTS: Group B was superior to group A in the success rate of anesthesia; There were 6 patients in group A who required constant pump injection of Remifentanil to remedy, while no patients in Group B needed remedy treatment. There were no serious adverse reactions in both groups.CONCLUSIONS: The clinical effect of brachial plexus block with "One Injection Two Points" method guided under ultrasoundguiding by ultrasound was superior to that of the conventional method. 展开更多
关键词 Clinical observation Ultrasound-guided Brachial plexus block "One Injection Two points" method
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Synthesis of Polyfluorene-Polytriarylamine Block Copolymer with Emitting Part at Junction Point for Light Emitting Applications 被引量:1
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作者 Mehdi Jahanfar Kenta Suwa +1 位作者 Kousuke Tsuchiya Kenji Ogino Ogino 《Open Journal of Organic Polymer Materials》 2013年第2期46-52,共7页
A block copolymer consisting of polyfluorene (PF) and polytriarylamine (PTAA) functionalized with green emitting phenoxazine moiety at the junction point of two blocks was designed and prepared for electroluminescent ... A block copolymer consisting of polyfluorene (PF) and polytriarylamine (PTAA) functionalized with green emitting phenoxazine moiety at the junction point of two blocks was designed and prepared for electroluminescent application. PF homopolymer was synthesized by Suzuki coupling polymerization, and was reacted with brominated phenoxazine. In the presence of the resulting PF functionalized with phenoxazine, C-N coupling polymerization of 4-(4’-bromophenyl)-4’’-butyldiphenylamine was carried out to afford a triblock copolymer, PTAA-phenoxazine-PF-phenoxazine-PTAA (PF-Ph-PTAA). Two types of random copolymers were also synthesized with fluorene and phenoxazine (PF2) by Suzuki coupling polymerization for comparison. All the polymers were soluble in common organic solvents and readily formed thin films by a solution processing. Prepared polymers exhibited similar UV absorption and PL emission in chloroform solutions. In a film state, the existence of phenoxazine unit drastically changed PL spectra. Although the content of phenoxazine unit in PF-Ph-PTAA was relatively high (13 mol%), it showed similar PL spectrum to that of PF2(phenoxazine content, 0.2 mol%) indicating that phenoxazine unit is isolated in single polymer chain nevertheless the high content. EL device based on PF-Ph-PTAA showed green-emission, suggesting that emission sites predominantly located in the vicinity of phenoxazine moiety because of its shallow HOMO level. 展开更多
关键词 POLYFLUORENE Polytriarylamine block Copolymer JUNCTION point Polymer LIGHT-EMITTING Diode
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Five Steps Block Predictor-Block Corrector Method for the Solution of <i>y''</i>= <i>f</i>(<i>x</i>,<i>y</i>,<i>y'</i>)
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作者 Mathew Remilekun Odekunle Michael Otokpa Egwurube +1 位作者 Adetola Olaide Adesanya Mfon Okon Udo 《Applied Mathematics》 2014年第8期1252-1266,共15页
Theory has it that increasing the step length improves the accuracy of a method. In order to affirm this we increased the step length of the concept in [1] by one to get k = 5. The technique of collocation and interpo... Theory has it that increasing the step length improves the accuracy of a method. In order to affirm this we increased the step length of the concept in [1] by one to get k = 5. The technique of collocation and interpolation of the power series approximate solution at some selected grid points is considered so as to generate continuous linear multistep methods with constant step sizes. Two, three and four interpolation points are considered to generate the continuous predictor-corrector methods which are implemented in block method respectively. The proposed methods when tested on some numerical examples performed more efficiently than those of [1]. Interestingly the concept of self starting [2] and that of constant order are reaffirmed in our new methods. 展开更多
关键词 Step Length Power Series block PREDICtoR block CORRECtoR Constant Order Step Size Grid points Self Starting Efficiency
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Optimization of block-floating-point realizations for digital controllers with finite-word-length considerations
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作者 吴俊 胡协和 +1 位作者 陈生 褚健 《Journal of Zhejiang University Science》 EI CSCD 2003年第6期651-657,共7页
The closed-loop stability issue of finite-precision realizations was investigated for digital control-lers implemented in block-floating-point format. The controller coefficient perturbation was analyzed resultingfrom... The closed-loop stability issue of finite-precision realizations was investigated for digital control-lers implemented in block-floating-point format. The controller coefficient perturbation was analyzed resultingfrom using finite word length (FWL) block-floating-point representation scheme. A block-floating-point FWL closed-loop stability measure was derived which considers both the dynamic range and precision. To facilitate the design of optimal finite-precision controller realizations, a computationally tractable block-floating-point FWL closed-loop stability measure was then introduced and the method of computing the value of this measure for a given controller realization was developed. The optimal controller realization is defined as the solution that maximizes the corresponding measure, and a numerical optimization approach was adopted to solve the resulting optimal realization problem. A numerical example was used to illustrate the design procedure and to compare the optimal controller realization with the initial realization. 展开更多
关键词 Digital controller Finite word length block floating point Closed loop stability OPTIMIZATION
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A New Preconditioner with Two Variable Relaxation Parameters for Saddle Point Linear Systems with Highly Singular(1,1) Blocks
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作者 Yuping Zeng Chenliang Li 《American Journal of Computational Mathematics》 2011年第4期252-255,共4页
In this paper, we provide new preconditioner for saddle point linear systems with (1,1) blocks that have a high nullity. The preconditioner is block triangular diagonal with two variable relaxation paremeters and it i... In this paper, we provide new preconditioner for saddle point linear systems with (1,1) blocks that have a high nullity. The preconditioner is block triangular diagonal with two variable relaxation paremeters and it is extension of results in [1] and [2]. Theoretical analysis shows that all eigenvalues of preconditioned matrix is strongly clustered. Finally, numerical tests confirm our analysis. 展开更多
关键词 SADDLE point Linear Systems block TRIANGULAR PRECONDITIONER Krylov SUBSPACE Methods
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A CLASS OF r-POINT (r+1)ST-ORDER A-STABLE ONE-BLOCK METHODS WITH DAMPING AT THE INFINITE POINT
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作者 Zhao Shuangsuo(赵双锁) +1 位作者 Zhang Guofeng(张国风) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2002年第2期161-178,共18页
This paper presents a class of r-point (r+1)st-order A-stable one-block methods with damping at the infinite point (DIAOB r,r+1 ). Under the conditions of the same order, A-stability, operation count (at each iterativ... This paper presents a class of r-point (r+1)st-order A-stable one-block methods with damping at the infinite point (DIAOB r,r+1 ). Under the conditions of the same order, A-stability, operation count (at each iterative step) and storage space are the same as the methods in , the methods in the paper improve the stability in a neighborhood at the infinite point. And, by using the OOPI method , it possesses much faster rate of convergence for solving systems of nonlinear equations produced by the DIAOB r,r+1 . 展开更多
关键词 one-block method STIFF problem A-stability DAMPING at INFINITE point.
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基于AutoCAD动态块和脚本文件的批量展点方法 被引量:3
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作者 唐桂彬 李俊锋 刘帅 《地理空间信息》 2016年第2期75-78,9,共4页
AutoCAD在工程测量领域有着较强的通用性,通过深入剖析AutoCAD属性块、动态块功能和脚本文件的运行原理,提出一种基于AutoCAD带属性动态块和脚本文件的批量展点方法,并运用VBA宏语言实现展点数据脚本文件的快速编写。实验表明,该方法不... AutoCAD在工程测量领域有着较强的通用性,通过深入剖析AutoCAD属性块、动态块功能和脚本文件的运行原理,提出一种基于AutoCAD带属性动态块和脚本文件的批量展点方法,并运用VBA宏语言实现展点数据脚本文件的快速编写。实验表明,该方法不但可同时完成点符号和点注记的展绘,而且能保证二者的整体性,具备较强的可调整性,有利于后期图面的清绘工作。 展开更多
关键词 AUtoCAD 动态图块 脚本文件 VBA 批量展点
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GPS Block IIF卫星频间钟差偏差分析 被引量:1
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作者 李黎 李浩军 +1 位作者 龙四春 张立亚 《大地测量与地球动力学》 CSCD 北大核心 2014年第3期169-172,共4页
使用37个IGS站的实测数据解算了4颗在轨Block IIF卫星(PRN01、PRN24、PRN25、PRN27)的IFCB值并进行特性分析。结果表明,目前所有GPS Blcok IIF卫星三频信号间存在的IFCB量级在cm到dm级;快速解算方法比非差估计方法更加省时高效;12、6、8... 使用37个IGS站的实测数据解算了4颗在轨Block IIF卫星(PRN01、PRN24、PRN25、PRN27)的IFCB值并进行特性分析。结果表明,目前所有GPS Blcok IIF卫星三频信号间存在的IFCB量级在cm到dm级;快速解算方法比非差估计方法更加省时高效;12、6、8、4 h的周期组合模型能较好地描述IFCB的变化,精度可达cm级;现有的IFCB计算方法、模型也适用于所有的Block IIF卫星。 展开更多
关键词 精密单点定位 三频信号 频间钟差偏差 block IIF卫星 历元间差分
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车载可见光视距通信系统块误码率的研究
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作者 牛明博 杨建 +1 位作者 黄小琼 李国兴 《汽车技术》 北大核心 2025年第1期33-40,共8页
为了提高车载通信质量和可靠性,通过分析基础设施与车辆间信道传输模型和道路基础设施参数的影响,引入车载可见光通信技术。根据基础设施与车辆间的视距信道进行建模,分析信号传输中的通信损耗;利用视距通信误码率(BER)、停机概率及块... 为了提高车载通信质量和可靠性,通过分析基础设施与车辆间信道传输模型和道路基础设施参数的影响,引入车载可见光通信技术。根据基础设施与车辆间的视距信道进行建模,分析信号传输中的通信损耗;利用视距通信误码率(BER)、停机概率及块误码率(BLER)推导系统性能的闭式解析式;分析复合指向误差对视距通信系统的误码率、停机概率以及块误码率的影响。试验结果表明:在无衰落和视距传输条件下,增加路灯高度可以降低误码率,通信链路距离增加将增大误码率;提高停机阈值,视距链路的停机概率降低;增加发送比特块数量有助于改善块误码率性能;考虑指向误差后,误码率、停机概率以及块误码率均增加,表明指向误差对系统通信有衰弱作用。 展开更多
关键词 可见光通信 误码率 停机概率 块误码率 复合指向误差
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基于block bootstrap的厚尾相依序列均值变点检验
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作者 秦瑞兵 杨晓琴 《贵州师范大学学报(自然科学版)》 CAS 2017年第5期56-59,共4页
针对无穷方差重尾相依序列的均值变点检验问题,基于序列自正则方法构造CUSUM型统计量,并在原假设下得到其渐近分布,在备择假设下得到检验的容许性。由于其渐近分布依赖于尾指数κ,且考虑到序列之间具有相依性,提出基于残差的block boots... 针对无穷方差重尾相依序列的均值变点检验问题,基于序列自正则方法构造CUSUM型统计量,并在原假设下得到其渐近分布,在备择假设下得到检验的容许性。由于其渐近分布依赖于尾指数κ,且考虑到序列之间具有相依性,提出基于残差的block bootstrap方法。蒙特卡洛模拟表明该检验统计量和该抽样方法的有效性。 展开更多
关键词 重尾 block BOOTSTRAP CUSUM检验 变点 自正则化
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西安丝路国际会议中心隔震节点构造研究
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作者 胡军锋 《城市建筑》 2025年第1期197-201,共5页
近年来,结构隔震设计越来越多地应用到工程实践之中。西安丝路国际会议中心作为大跨度复杂结构的典型案例,通过结构隔震技术运用,有效减小地震作用并提高结构抗震性能。当然,结构隔震技术的运用会给建筑设计带来难度,特别是可位移的墙... 近年来,结构隔震设计越来越多地应用到工程实践之中。西安丝路国际会议中心作为大跨度复杂结构的典型案例,通过结构隔震技术运用,有效减小地震作用并提高结构抗震性能。当然,结构隔震技术的运用会给建筑设计带来难度,特别是可位移的墙体和柱头等,给建筑墙体封堵和管线布置都带来新的挑战。文章以西安丝路国际会议中心项目为例,分析结构隔震技术运用对建筑封堵的新要求,梳理隔震节点构造设计的要点与难点问题,并提出针对性的解决措施,以期为类似工程案例提供参考。 展开更多
关键词 建筑隔震封堵 要点难点 节点构造
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全钢轮胎包络刚性试验研究
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作者 张存猛 王君 周磊 《轮胎工业》 2025年第1期52-58,共7页
以全钢轮胎为研究对象,采用不同尺寸的包络块,分析不同加载速度下轮胎径向负荷与凸起位移之间的关系,并用斜率法和两点法分别对不同径向负荷区间的包络刚性进行求解分析。结果表明:在初始状态下,轮胎的包络刚性不受包络块顶点半角、最... 以全钢轮胎为研究对象,采用不同尺寸的包络块,分析不同加载速度下轮胎径向负荷与凸起位移之间的关系,并用斜率法和两点法分别对不同径向负荷区间的包络刚性进行求解分析。结果表明:在初始状态下,轮胎的包络刚性不受包络块顶点半角、最终加载负荷的影响;采用径向负荷>5 000 N的数据计算的包络刚性值与采用整体数据计算的包络刚性值较为接近,径向负荷≤5 000 N的数据对结果影响较小。 展开更多
关键词 全钢轮胎 包络刚性 两点法 斜率法 包络块顶点半角
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基于PointNet++的船体分段合拢面智能识别方法 被引量:4
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作者 陈尚伟 汪骥 +1 位作者 刘玉君 张学晨 《船舶工程》 CSCD 北大核心 2019年第12期138-141,共4页
船体分段合拢面的精度检测是分段总组合拢过程中的重要环节。在船体分段合拢面的精度检测方面,三维扫描仪相对全站仪有着巨大优势,但三维扫描仪在扫描过程中会记录很多与合拢面无关的点。文章对三维扫描仪扫描出的点云数据进行合拢面的... 船体分段合拢面的精度检测是分段总组合拢过程中的重要环节。在船体分段合拢面的精度检测方面,三维扫描仪相对全站仪有着巨大优势,但三维扫描仪在扫描过程中会记录很多与合拢面无关的点。文章对三维扫描仪扫描出的点云数据进行合拢面的智能识别;采用深度学习理论对PointNet++点云网络进行改进,使用CAD模型导出的点云数据构建有标注的船体分段点云数据集,进而使用Adam优化算法对网络进行优化训练。最终,网络模型对分段合拢面的识别在验证集上获得精确率73%、召回率90%的效果。 展开更多
关键词 三维扫描仪 点云 pointNet++ 船体分段合拢面 深度学习
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42号大号码道岔心轨不解锁问题研究
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作者 李振武 郑起 +2 位作者 赵常伟 万大磊 徐健 《铁道通信信号》 2025年第1期104-107,共4页
42号大号码道岔通常设置于高铁正线2条线路交汇处或线路所,而作为不同高铁线路的岔路口,线路所多为无人值守。当道岔出现故障后,维修人员处理时间相对较长,对行车影响较大。为此,沈阳高铁基础设施段经过近3年对京哈高速线、哈大高速线22... 42号大号码道岔通常设置于高铁正线2条线路交汇处或线路所,而作为不同高铁线路的岔路口,线路所多为无人值守。当道岔出现故障后,维修人员处理时间相对较长,对行车影响较大。为此,沈阳高铁基础设施段经过近3年对京哈高速线、哈大高速线22组42号大号码道岔心轨不解锁问题进行深度分析,发现温度变化和结构因素是造成道岔心轨不解锁的主要原因。通过数据比对和研究试验,采取调整道岔框架尺寸、几何参数、道岔密贴力,以及改进外锁闭配件结构等措施,同时规范42号大号码道岔工电联合整治作业流程,可初步解决42号大号码道岔心轨不解锁问题,有益于保障高速铁路行车安全。 展开更多
关键词 高速铁路 大号码道岔 提速道岔 卡阻故障 工电联调
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Rocking Block线碰撞离散化研究 被引量:2
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作者 张宏剑 庄方方 +2 位作者 王辰 季宝锋 石玉红 《动力学与控制学报》 2017年第4期330-334,共5页
针对Rocking Block中的线碰撞问题,首先采用离散化思想将线碰撞问题离散为多点碰撞系统,而后基于LZB方法对所建多点碰撞系统进行动力学建模.仿真结果表明随着离散点数的增加,基于LZB方法的多点碰撞模型能够很好地刻画Rocking Block中的... 针对Rocking Block中的线碰撞问题,首先采用离散化思想将线碰撞问题离散为多点碰撞系统,而后基于LZB方法对所建多点碰撞系统进行动力学建模.仿真结果表明随着离散点数的增加,基于LZB方法的多点碰撞模型能够很好地刻画Rocking Block中的相关线碰撞问题,且精度与离散程度紧密相关. 展开更多
关键词 线碰撞 多点碰撞 非光滑动力学 ROCKING block
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Hybrid Numerical Method with Block Extension for Direct Solution of Third Order Ordinary Differential Equations 被引量:2
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作者 M. K. Duromola A. L. Momoh 《American Journal of Computational Mathematics》 2019年第2期68-80,共13页
This paper focuses on the development of a hybrid method with block extension for direct solution of initial value problems (IVPs) of general third-order ordinary differential equations. Power series was used as the b... This paper focuses on the development of a hybrid method with block extension for direct solution of initial value problems (IVPs) of general third-order ordinary differential equations. Power series was used as the basis function for the solution of the IVP. An approximate solution from the basis function was interpolated at some selected off-grid points while the third derivative of the approximate solution was collocated at all grid and off-grid points to generate a system of linear equations for the determination of the unknown parameters. The derived method was tested for consistency, zero stability, convergence and absolute stability. The method was implemented with five test problems including the Genesio equation to confirm its accuracy and usability. The rate of convergence (ROC) reveals that the method is consistent with the theoretical order of the proposed method. Comparison of the results with some existing methods shows the superiority of the accuracy of the method. 展开更多
关键词 HYBRID Modified block Grid pointS Interpolation and COLLOCATION
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基于AutoCAD的地表离散点预计程序设计与软件实现 被引量:1
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作者 田迎斌 李幸丽 《煤炭工程》 北大核心 2020年第5期111-115,共5页
在"三下采煤"研究工作过程中经常需要对地表分布的离散点进行开采沉陷预计,以获得建(构)筑物移动和变形的具体数值,为煤矿地下开采方案设计和地表建(构)筑物损坏级别预测等提供依据。按照常规预计方法和技术手段,预计过程中... 在"三下采煤"研究工作过程中经常需要对地表分布的离散点进行开采沉陷预计,以获得建(构)筑物移动和变形的具体数值,为煤矿地下开采方案设计和地表建(构)筑物损坏级别预测等提供依据。按照常规预计方法和技术手段,预计过程中基础数据的获取、组织和修改等操作过程效率较低且易出错。针对上述问题,提出了通过在AutoCAD中创建带属性的工作面和离散点参照块,并通过AutoLisp程序提取和组建工作面预计参数数据文件和离散点数据文件,然后调用概率积分法预计程序获得了离散点的预计结果。同时,开发了工作面属性扩展、离散点预计和绘制离散点移动变形曲线等相关命令,并进行了程序设计和软件实现。 展开更多
关键词 CAD 离散点预计 扩展属性 参照块
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Dynamical signatures of the one-dimensional deconfined quantum critical point
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作者 Ning Xi Rong Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期73-82,共10页
We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product... We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product states.The scaling of the correlation functions and the dispersion of the conserved current correlations explicitly show the emergence of enhanced continuous symmetries at these DQCPs.The dynamical structure factors in several different channels reveal the development of deconfined fractionalized excitations at the DQCPs.Furthermore,we find an effective spin-charge separation at the DQCP between the ferromagnetic(FM)and valence bond solid(VBS)phases,and identify two continua associated with different types of fractionalized excitations at the DQCP between the X-direction and Z-direction FM phases.Our findings not only provide direct evidence for the DQCP in one dimension but also shed light on exploring the DQCP in higher dimensions. 展开更多
关键词 one-dimensional antiferromagnetism spin frustration deconfined quantum critical point spin dynamics infinite time-evolving block decimation
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Numerical Solution of Nonlinear Fredholm-Volterra Integtral Equations via Piecewise Constant Function by Collocation Method 被引量:1
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作者 A. Shahsavaran 《American Journal of Computational Mathematics》 2011年第2期134-138,共5页
In this work, we present a computational method for solving nonlinear Fredholm-Volterra integral equations of the second kind which is based on replacement of the unknown function by truncated series of well known Blo... In this work, we present a computational method for solving nonlinear Fredholm-Volterra integral equations of the second kind which is based on replacement of the unknown function by truncated series of well known Block-Pulse functions (BPfs) expansion. Error analysis is worked out that shows efficiency of the method. Finally, we also give some numerical examples. 展开更多
关键词 NONLINEAR Fredholm-Volterra Integral Equation block-Pulse FUNCTION Error Analysis COLLOCATION points
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