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Elementary Fermions: Strings, Planck Constant, Preons and Hypergluons
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期82-100,共19页
Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism ... Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism which is proportional to Planck’s constant. This may be the result of two massless bosons (hypergluons) coupled by a preon (prequark) exchange. It also gives a physical explanation to the origin of the Planck constant, and origin of spin. 展开更多
关键词 FERMIONS Preons Hypergluons strings Real Fields Planck Constant INTERFERENCE SPIN
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Stringy Phenomenology with Preon Models
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期1-7,共7页
We compare, following Pati, global symmetries, our topological supersymmetric preon model with the heterotic E<sub>8</sub> × E<sub>8</sub> string theory. We include Pati’s supergravity ba... We compare, following Pati, global symmetries, our topological supersymmetric preon model with the heterotic E<sub>8</sub> × E<sub>8</sub> string theory. We include Pati’s supergravity based preon model in this work and compare the preon interactions of his model to ours. Based on preon-string symmetry comparison and preon phenomenological results, we conclude that the fundamental particles are likely preons rather than standard model particles. . 展开更多
关键词 Topological Field Theory Chern-Simons Theory SUPERSYMMETRY string Theory
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Towards 6D Little String Theory of Particles
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期546-561,共16页
A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predicti... A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predictions are discussed. 展开更多
关键词 Standard Model Composite Models SUPERSYMMETRY Little string Theory T-DUALITY HOLOGRAPHY
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Investigating the expression profiles of cysteine string proteins(CSPs)in cochlear tissue
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作者 Shili Zhang Caiji Wang +1 位作者 Yuehua Qiao Xi Shi 《Journal of Otology》 CAS CSCD 2024年第4期193-199,共7页
Objective:This study aims to explore the expression patterns of cysteine string protein alpha(CSPα)and cysteine string protein beta(CSPβ)in the mammalian inner ear,with an emphasis on their temporal dynamics during ... Objective:This study aims to explore the expression patterns of cysteine string protein alpha(CSPα)and cysteine string protein beta(CSPβ)in the mammalian inner ear,with an emphasis on their temporal dynamics during the developmental stages of C57BL/6 mice.Methods:We utilized immunofluorescence staining to assess the localization and distribution of CSPαand CSPβwithin the inner ears of C57BL/6 mice and miniature pigs.Additionally,this method facilitated the investigation of their temporal expression profiles.Results:In adult C57BL/6 mice and miniature pigs,CSPαand CSPβwere identified in the cytoplasm of inner hair cells and spiral ganglion cells,yet were absent in outer hair cells.Both proteins were found to colocalize with Ctbp2 on the basal side of the cytoplasm in inner hair cells’basilar membrane.Expression of CSPαwas observed at the nerve fiber termini at the basilar membrane’s base of inner and outer hair cells 10 days postnatally in C57BL/6 mice.Notably,expression of both CSPαand CSPβin the cytoplasm of inner hair cells emerged on the 12th day post-birth,aligning with the timeline for registering cochlear potentials.The expression levels of both proteins increased with age,but were consistently absent in outer hair cells.Contrastingly,expression of CSPαand CSPβwas present in the cytoplasm of inner hair cells in miniature pigs as early as one day post-birth,yet remained absent in the three rows of outer hair cells.Conclusion:CSPαand CSPβexhibit predominant and specific expression in inner hair cells and spiral ganglion cells.A unique expression pattern was observed for CSPα,which was also present at the nerve fiber endings of both inner and outer hair cells.The developmental expression trajectory of CSPαand CSPβin mouse inner hair cells is characterized by an initial absence,followed by a gradual increase.Moreover,the timing of expression onset between mice and miniature pigs indicates distinct temporal dynamics,suggesting a potential role in auditory development. 展开更多
关键词 Cysteine string protein CSPα CSPβ Miniature pig C57BL/6 mouse
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Detachable string magnetically controlled capsule endoscopy for the noninvasive diagnosis of esophageal diseases:A prospective,blind clinical study
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作者 Yan-Ling Yang Huang-Wen Qin +5 位作者 Zhao-Yu Chen Hui-Ning Fan Yi Yu Wei Da Jin-Shui Zhu Jing Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1121-1131,共11页
BACKGROUND Traditional esophagogastroduodenoscopy(EGD),an invasive examination method,can cause discomfort and pain in patients.In contrast,magnetically controlled capsule endoscopy(MCE),a noninvasive method,is being ... BACKGROUND Traditional esophagogastroduodenoscopy(EGD),an invasive examination method,can cause discomfort and pain in patients.In contrast,magnetically controlled capsule endoscopy(MCE),a noninvasive method,is being applied for the detection of stomach and small intestinal diseases,but its application in treating esophageal diseases is not widespread.AIM To evaluate the safety and efficacy of detachable string MCE(ds-MCE)for the diagnosis of esophageal diseases.METHODS Fifty patients who had been diagnosed with esophageal diseases were pros-pectively recruited for this clinical study and underwent ds-MCE and conven-tional EGD.The primary endpoints included the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for patients with esophageal diseases.The secondary endpoints consisted of visualizing the esophageal and dentate lines,as well as the subjects'tolerance of the procedure.RESULTS Using EGD as the gold standard,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for esophageal disease detection were 85.71%,86.21%,81.82%,89.29%,and 86%,respectively.ds-MCE was more comfortable and convenient than EGD was,with 80%of patients feeling that ds-MCE examination was very comfortable or comfortable and 50%of patients believing that detachable string v examination was very convenient.CONCLUSION This study revealed that ds-MCE has the same diagnostic effects as traditional EGD for esophageal diseases and is more comfortable and convenient than EGD,providing a novel noninvasive method for treating esophageal diseases. 展开更多
关键词 Clinical trial Detachable string magnetically controlled capsule endoscopy ESOPHAGOGASTRODUODENOSCOPY Noninvasive diagnosis Esophageal diseases
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深入探讨Java中的String类 被引量:1
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作者 李斌 王睿 何成芊 《长沙通信职业技术学院学报》 2009年第3期42-44,共3页
文章分析了java的String类的本质,在此基础上,对其创建原理作了更为详尽的阐述。
关键词 JAVA string string string对象创建
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基于String Kernel和KPCA的负实例语法特征提取算法
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作者 吕威 林文昶 +1 位作者 姚正安 李磊 《计算机工程与应用》 CSCD 北大核心 2009年第20期136-139,共4页
提出通过String Kernel方法把负实例语法数据库中的负实例转化成核矩阵,再用Kernel Principal Component Analysis(KPCA)对转换的核矩阵进行特征提取,进而可将原始负实例数据库按照这些特征分成多个容量较小的特征表。通过构造负实例特... 提出通过String Kernel方法把负实例语法数据库中的负实例转化成核矩阵,再用Kernel Principal Component Analysis(KPCA)对转换的核矩阵进行特征提取,进而可将原始负实例数据库按照这些特征分成多个容量较小的特征表。通过构造负实例特征索引表设计了一个分类器,待检查的句子通过此分类器被分配到某个负实例特征表里进行匹配搜索,而此特征表的特征属性数和记录数要远远小于原始负实例数据库中的相应数目,从而大大提高了检查的速度,同时不影响语法检查的精度。通过比较测试,可看出提出的方法在保证语法检查精确度的同时有更快的速度。 展开更多
关键词 string KERNEL 核主成分分析 负实例 特征提取
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String核负实例语法特征提取算法
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作者 吕威 林文昶 李磊 《计算机工程》 CAS CSCD 北大核心 2009年第23期12-14,共3页
通过String核方法把语法数据库中的负实例转化成核矩阵,采用Kmeans聚类算法对核矩阵进行聚类,将原始负实例数据库分成多个容量较小的特征数据表,使大规模O(n3)核矩阵转换为n/s×O(s3)(s<<n)矩阵,以减少运算量。分析语法检查... 通过String核方法把语法数据库中的负实例转化成核矩阵,采用Kmeans聚类算法对核矩阵进行聚类,将原始负实例数据库分成多个容量较小的特征数据表,使大规模O(n3)核矩阵转换为n/s×O(s3)(s<<n)矩阵,以减少运算量。分析语法检查精度随Kmeans聚类参数的变化规律。实验结果表明,该算法在不降低语法检查精度的前提下提高了语法检查速度。 展开更多
关键词 Kmeans方法 聚类 string 负实例 特征提取
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Suppression strategy for parametrically excited lateral vibration of mass-loaded string
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作者 张长友 朱昌明 林忠钦 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期165-169,共5页
This paper discusses a simple way to suppress the parametrically excited lateral vibration of a mass-loaded string. Supposing that the mass at the lower end of the string is subjected to a vertical harmonic excitation... This paper discusses a simple way to suppress the parametrically excited lateral vibration of a mass-loaded string. Supposing that the mass at the lower end of the string is subjected to a vertical harmonic excitation and neglecting the higher order vibration modes, the equation of motion for the mass-loaded string can be represented by a Mathieus equation with cubic nonlinearity. According to the theory of the Mathieus equation, in the mass-loaded string system, when the vertical vibration frequency of the mass approaches twice the natural frequency of the string lateral vibration, once the vertical vibration amplitude of the mass exceeds a critical value, the parametric resonance will occur in the string. To avoid the parametric resonance, a vibration absorber, composed of a thin beam and two mass blocks attached at both sides of the beam symmetrically, is proposed to install with the mass to reduce its vertical vibration, and ultimately suppress the lateral vibration of the string. Such a suppression strategy is finally validated by experiments. 展开更多
关键词 mass-loaded string parametric resonance vibration absorber
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StringB-tree在软件复用中的应用研究
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作者 姚全珠 罗亚红 孙越 《计算机工程与应用》 CSCD 北大核心 2004年第29期166-168,共3页
提出了将StringB-tree用于解决软件复用中的参数化样式匹配问题(parameterizedpatternmatching)。通过对参数化字符串做一个变换,使用StringB-tree这种特殊的数据结构可提高匹配效率。文章的重点有两部分,一个是介绍了StringB-tree这种... 提出了将StringB-tree用于解决软件复用中的参数化样式匹配问题(parameterizedpatternmatching)。通过对参数化字符串做一个变换,使用StringB-tree这种特殊的数据结构可提高匹配效率。文章的重点有两部分,一个是介绍了StringB-tree这种特殊的数据结构的优点及其构建过程;另一个是讲怎样利用StringB-tree解决参数化样式匹配问题。 展开更多
关键词 字符串平衡树参数化字符串 参数化样式匹配 P-匹配 P-出现
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AR-序列的中间项与String代数
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作者 林卫强 《漳州师院学报》 2000年第2期21-23,共3页
设A是一次monomial代数。
关键词 onomil代数 AR序列 中间项 string代数
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浅析String类中“= =”和equals的应用
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作者 陈益 童亚拉 《数字技术与应用》 2010年第2期110-111,共2页
String是编程中常用到的数据类型,Java中的String类是一种引用数据类型。它将从String类对象的两种创建方式入手,分析字符串作比较时"= ="和equals( )的具体应用。
关键词 equal 字符串 数据类型
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String方法在丙氨酸多肽链中的应用 被引量:1
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作者 贾红霞 靳聪明 《浙江理工大学学报(自然科学版)》 2016年第2期297-303,共7页
蛋白质的构象变化在生命过程中起着重要的作用,蛋白质在发挥其功能时常伴有构象变化,有些疾病也是由蛋白质的构象发生变化引起的,典型的例子如老年痴呆、疯牛病等就是某些蛋白质的构象由水溶性的蛋白变成了不溶性的纤维性蛋白引起的。... 蛋白质的构象变化在生命过程中起着重要的作用,蛋白质在发挥其功能时常伴有构象变化,有些疾病也是由蛋白质的构象发生变化引起的,典型的例子如老年痴呆、疯牛病等就是某些蛋白质的构象由水溶性的蛋白变成了不溶性的纤维性蛋白引起的。知道构象变化的过程对理解蛋白质相关性质起着重要作用,但从原子尺度研究构象变化是极具挑战的问题。文章利用String方法从原子尺度研究了多肽链的310-螺旋和α-螺旋之间的构象变化。文中用零温度String方法研究多肽链310-螺旋和α-螺旋之间的构象变化,从不同的初始路径得到了不同的最优路径和过渡态,其中有显著势垒的过渡态是与310-螺旋相似的构型;利用有限温度String方法研究多肽的构象变化,采用了Langevin动力学和分子动力学两种采样法,得到了它的转移路径系综,通过与零温度String方法结果比较说明了模拟结果的有效性。 展开更多
关键词 string方法 多肽链 转移路径 构象变化
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Study of Temperature Distribution Along an Artificially Polluted Insulator String 被引量:24
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作者 B Subba Reddy G R Nagabhushana 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第2期1715-1720,共6页
Insulator becomes wet partially or completely, and the pollution layer on itbecomes conductive, when collecting pollutants for an extended period during dew, light rain, mist,fog or snow melting. Heavy rain is a compl... Insulator becomes wet partially or completely, and the pollution layer on itbecomes conductive, when collecting pollutants for an extended period during dew, light rain, mist,fog or snow melting. Heavy rain is a complicated factor that it may wash away the pollution layerwithout initiating other stages of breakdown or it may bridge the gaps between sheds to promoteflashover. The insulator with a conducting pollution layer being energized, can cause a surfaceleakage current to flow (also temperature-rise). As the surface conductivity is non-uniform, theconducting pollution layer becomes broken by dry bands (at spots of high current density),interrupting the flow of leakage current. Voltage across insulator gets concentrated across drybands, and causes high electric stress and breakdown (dry band arcing). If the resistance of theinsulator surface is sufficiently low, the dry band arcs can be propagated to bridge the terminalscausing flashover. The present paper concerns the evaluation of the temperature distribution alongthe surface of an energized artificially polluted insulator string. 展开更多
关键词 temperature distribution artificially polluted insulator string
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Cooperative adaptive bidirectional control of a train platoon for efficient utility and string stability 被引量:6
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作者 高士根 董海荣 +3 位作者 宁滨 Roberts Clive 陈磊 孙绪彬 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期161-170,共10页
This paper proposes cooperative adaptive control schemes for a train platoon to improve efficient utility and guarantee string stability. The control schemes are developed based on a bidirectional strategy, i.e., the ... This paper proposes cooperative adaptive control schemes for a train platoon to improve efficient utility and guarantee string stability. The control schemes are developed based on a bidirectional strategy, i.e., the information of proximal(preceding and following) trains is used in the controller design. Based on available proximal information(prox-info) of location, speed, and acceleration, a direct adaptive control is designed to maintain the tracking interval at the minimum safe distance. Based on available prox-info of location, an observer-based adaptive control is designed to achieve the same target, which alleviates the requirements of equipped sensors to measure prox-info of speed and acceleration. The developed schemes are capable of on-line estimating of the unknown system parameters and stabilizing the closed-loop system, the string stability of train platoon is guaranteed on the basis of Lyapunov stability theorem. Numerical simulation results are presented to verify the effectiveness of the proposed control laws. 展开更多
关键词 train platoon string stability cooperative adaptive control efficient utility
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Function of note strings in Japanese Tit alarm calls to the Common Cuckoo:a playback experiment 被引量:10
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作者 Jiangping Yu Weiwei Lv +5 位作者 Hongwei Xu Nehafta Bibi Yangyang Yu Yunlei Jiang Wei Liang Haitao Wang 《Avian Research》 CSCD 2017年第3期141-146,共6页
Background: Birds produce alarm calls to convey information about threats. Some Passerine alarm calls consist of several note strings, but few studies have examined their function. Previous studies have shown that Jap... Background: Birds produce alarm calls to convey information about threats. Some Passerine alarm calls consist of several note strings, but few studies have examined their function. Previous studies have shown that Japanese Tits(Parus minor) can alter the calling rate and number and combination of notes in response to predators. We previously found the combinations of note types in Japanese Tit alarm calls to be significantly different in response to the Sparrowhawk(Accipiter nisus) and Common Cuckoo(Cuculus canorus).Methods: Through playback experiments, we tested whether the note strings in Japanese Tit alarm calls to the Common Cuckoo have different functions in conveying information. The note strings of selected alarm calls were divided into the categories of C and D, and different calls were then constructed separately based on the two note string categories. Original alarm calls(C–D), C calls and D calls were played back to male Japanese Tits during the incubation period.Results: Male Japanese Tits had a significantly stronger response to C calls than to C–D calls, and they showed a significantly stronger response to both C and C–D calls than to D calls, suggesting that Japanese Tits discriminated between the C and D calls.Conclusions: Our study demonstrated that the C-and D-category note strings of Japanese Tit alarm calls to the Common Cuckoo have different functions, which supports the previous finding that different note strings in an alarm call can provide different information to receivers. However, the exact meanings of these note strings are not yet known, and further investigation is therefore required. 展开更多
关键词 Alarm call Male Japanese Tit Note strings FUNCTION Brood parasitism PLAYBACK
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PRINCIPAL RESONANCE IN TRANSVERSE NONLINEAR PARAMETRIC VIBRATION OF AN AXIALLY ACCELERATING VISCOELASTIC STRING 被引量:4
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作者 陈立群 Jean W.ZU 吴俊 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2004年第3期307-316,共10页
To investigate the principal resonance in transverse nonlinear parametric vibration of an axially accelerating viscoelastic string,the method of multiple scales is applied directly to the nonlinear partial differentia... To investigate the principal resonance in transverse nonlinear parametric vibration of an axially accelerating viscoelastic string,the method of multiple scales is applied directly to the nonlinear partial differential equation that governs the transverse vibration of the string.To derive the governing equation,Newton's second law,Lagrangean strain,and Kelvin's model are respectively used to account the dynamical relation,geometric nonlinearity and the viscoelasticity of the string material. Based on the solvability condition of eliminating the secular terms,closed form solutions are obtained for the amplitude and the existence conditions of nontrivial steady-state response of the principal parametric resonance.The Lyapunov linearized stability theory is employed to analyze the stability of the trivial and nontrivial solutions in the principal parametric resonance.Some numerical examples are presented to show the effects of the mean transport speed,the amplitude and the frequency of speed variation. 展开更多
关键词 principal parametric resonance axially accelerating string VISCOELASTICITY method of multiple scales stability
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Simulations of the flipping images and microparameters of molecular orientations in liquids according to the molecule string model 被引量:3
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作者 王丽娜 赵兴宇 +1 位作者 张丽丽 黄以能 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期392-397,共6页
The relaxation dynamics of liquids is one of the fundamental problems in liquid physics, and it is also one of the key issues to understand the glass transition mechanism. It will undoubtedly provide enlightenment on ... The relaxation dynamics of liquids is one of the fundamental problems in liquid physics, and it is also one of the key issues to understand the glass transition mechanism. It will undoubtedly provide enlightenment on understanding and calculating the relaxation dynamics if the molecular orientation flipping images and relevant microparameters of liquids are studied. In this paper, we first give five microparameters to describe the individual molecular string (MS) relaxation based on the dynamical Hamiltonian of the MS model, and then simulate the images of individual MS ensemble, and at the same time calculate the parameters of the equilibrium state. The results show that the main molecular orientation flipping image in liquids (including supercooled liquid) is similar to the random walk. In addition, two pairs of the parameters are equal, and one can be ignored compared with the other. This conclusion will effectively reduce the difficulties in calculating the individual MS relaxation based on the single-molecule orientation flipping rate of the general Glauber type, and the computer simulation time of interaction MS relaxation. Moreover, the conclusion is of reference significance for solving and simulating the multi-state MS model. 展开更多
关键词 relaxation dynamics glass transition Ising model molecular string
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Effect of information delay on string stability of platoon of automated vehicles under typical information frameworks 被引量:11
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作者 肖凌云 高峰 《Journal of Central South University》 SCIE EI CAS 2010年第6期1271-1278,共8页
The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal ve... The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal vehicle dynamics model was built by taking the information delay into consideration, and three typical information frameworks, i.e., leader-predecessor framework (LPF), multiple-predecessors framework (MPF) and predecessor-successor framework (PSF), were defined and their related spacing error dynamics models in frequency domain were proposed. The string stability of platoon of automated vehicles was analyzed for the LPF, MPF and PSF, respectively. Meanwhile, the related sufficient string stable conditions were also obtained. The results demonstrate that the string stability can be guaranteed tbr the LPF and PSF with considering the information delay, but the ranges of the control gains of the control laws are smaller than those without considering the information delay. For the MPF, the "weak" string stability, which can be guaranteed without considering the information delay, cannot be obtained with considering the information delay. The comparative simulations further demonstrate that the LPF shows better string stability, but the PSF shows better string scalable performance. 展开更多
关键词 string stability information delay information framework automated vehicle intelligent transportation system
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Influence of friction on buckling of a drill string in the circular channel of a bore hole 被引量:2
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作者 Valery Gulyayev Natalya Shlyun 《Petroleum Science》 SCIE CAS CSCD 2016年第4期698-711,共14页
Enhancement of technology and techniques for drilling deep directed oil and gas bore hole is one of the most important problems of the current petroleum industry.Not infrequently, the drilling of these bore holes is a... Enhancement of technology and techniques for drilling deep directed oil and gas bore hole is one of the most important problems of the current petroleum industry.Not infrequently, the drilling of these bore holes is attended by occurrence of extraordinary situations associated with technical accidents. Among these is the Eulerian loss of stability of a drill string in the channel of a curvilinear bore hole. Methods of computer simulation should play a dominant role in prediction of these states. In this paper, a new statement of the problem of critical buckling of the drill strings in 3D curvilinear bore holes is proposed. It is based on combined use of the theory of curvilinear elastic rods, Eulerian theory of stability, theory of channel surfaces, and methods of classical mechanics of systems with nonlinear constraints. It is noted that the stated problem is singularly perturbed and its solutions have the shapes of localized harmonic wavelets. The calculation results showed that the friction effects lead to essential redistribution of internal axial forces, as well as changing the eigenmode shapes and sites of their localization. These features make the buckling phenomena less predictable and raise the role of computer simulation of these effects. 展开更多
关键词 Directed bore hole Drill string Critical states Singular perturbation Friction forces Harmonic wavelet
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