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Characterization of Pattern Formation from Modulation Instability in the Cubic Schrodinger Equation

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Chinese Physics Letters 1998年第9期15卷 659-661页

作者： LONG Tao he xian-tu Graduate School China Academy of Engineering PhysicsBeijing 100088 Institute of Applied Physics and Computational Mathematics Beijing 100088 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

The study of pattern dynamics in a Hamiltonian system(HS)having an infinite number of degree of freedom is very difficult due to the absence of attractors in such *** this letter,we propose a useful method that only a few representative manifolds in phase space are investigated,and it can be used to reveal the pattern formation of *** conserved cubic Schrödinger equation is *** a special model is chosen,this method can be applied to more general case such as the near-integrable HS.

关键词： integrable letter infinite

Diagnostic performance of intravascular ultrasound-based fractional flow reserve in evaluating of intermediate left main stenosis

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Journal of Geriatric Cardiology 2024年第1期21卷 34-43页

作者： Yong-Gang SUI Cheng YANG Chang-Dong GUAN Yan-Lu XU Na-Qiong WU Wei-xian YANG Yong-Jian WU Ke-Fei DOU Yue-Jin YANG Shu-Bin QIAO Wei YU Bo XU Sheng-xian tu Jie QIAN Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Catheterization Laboratories Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Biomedical Instrument Institute School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina National Clinical Research Center for Cardiovascular Diseases BeijingChina

BACKGROUND The recently introduced ultrasonic flow ratio(UFR),is a novel fast computational method to derive fractional flow reserve(FFR)from intravascular ultrasound(IVUS)*** the present study,we evaluate the diagnostic performance of UFR in patients with intermediate left main(LM)*** This is a prospective,single center study enrolling consecutive patients with presence of intermediated LM lesions(diameter stenosis of 30%-80%by visual estimation)underwent IVUS and FFR *** independent core laboratory assessed offline UFR and IVUS-derived minimal lumen area(MLA)in a blinded *** Both UFR and FFR were successfully achieved in 41 LM patients(mean age,62.0±9.9 years,46.3%diabetes).An acceptable correlation between UFR and FFR was identified(r=0.688,Phe area under the curve(AUC)in diagnosis of physiologically significant coronary stenosis for UFR was 0.94(95%CI:0.87-1.01),which was significantly higher than angiographic identified stenosis>50%(AUC=0.66,Pher than IVUS-derived MLA(AUC=0.82;P=0.09).Patient level diagnostic accuracy,sensitivity and specificity for UFR to identify FFR≤0.80 was 82.9%(95%CI:70.2-95.7),93.1%(95%CI:82.2-100.0),58.3%(95%CI:26.3-90.4),*** In patients with intermediate LM diseases,UFR was proved to be associated with acceptable correlation and high accuracy with pressure wire-based FFR as standard *** present study supports the use of UFR for functional evaluation of intermediate LM stenosis.

关键词： stenosis flow fractional

Quasistatic Magnetic Field Generation by an Intense Ultrashort Laser Pulse in Underdense Plasma

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Chinese Physics Letters 2000年第10期17卷 746-748页

作者： ZheNG Chun-Yang ZHU Shao-ping he xian-tu Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088

The quasistatic magnetic field created in the interaction of intense ultrashort laser pulses with underdense plasmas has been investigated by two-dimensional particle *** relativistic ponderomotive force and plasma wave excited in self-modulation processes can drive intense electron current mainly in the propagation *** a result,an azimuthal,multi-mega Gauss order quasi-static magnetic field can be generated around the laserbeam.

关键词： ultrashort intense Pulse

滇中磨盘山不同演替阶段林分结构及物种多样性研究

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西北林学院学报 2024年第3期39卷 67-76页

作者：欧阳田甜赵洋毅涂晓云和娴越王帅兵段旭西南林业大学生态与环境学院云南昆明650224 国家林业和草原局云南玉溪森林生态系统国家定位观测研究站云南昆明650224 玉溪师范学院化学生物与环境学院云南玉溪653100

为探明中亚热带不同演替阶段林分结构特征及其与物种多样性的关系,以滇中磨盘山处于演替前期、中期和后期的针叶纯林、针阔混交林、常绿阔叶林3种典型林分为对象,量化研究不同演替阶段林分空间结构多个指标变化规律和物种多样性指数的差... 详细信息

为探明中亚热带不同演替阶段林分结构特征及其与物种多样性的关系,以滇中磨盘山处于演替前期、中期和后期的针叶纯林、针阔混交林、常绿阔叶林3种典型林分为对象,量化研究不同演替阶段林分空间结构多个指标变化规律和物种多样性指数的差异,并借助冗余分析探究二者间相互作用关系;再利用多元分布对林分空间结构参数进行全面描述和综合评价。结果表明,林分空间结构参数在不同演替阶段林分中差异显著,群落演替对树种混交度、林层差异度的影响最大,均在演替后期达到最大值,分别为0.703、0.511;综合比较多元分布结果发现,3种林分类型中,以常绿阔叶林空间结构相对最为合理;乔木层物种丰富度、Simpson指数、Shannon-Weiner指数和Pielou均匀度指数均随着演替进展而上升,并在常绿阔叶林中各指数最高;树种隔离程度是影响乔木层物种多样性的主要驱动因子,其次是胸径结构及林分密度。研究结果可为该地区林分结构调整和森林可持续经营提供理论依据。

关键词：林分结构物种多样性多元分布群落演替磨盘山

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中药单体及提取物涂层冠脉介入器械的研究进展

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中国中药杂志 2024年第15期49卷 4022-4030页

作者：赖思佳王达洋王保福涂婧贻王显北京中医药大学东直门医院北京100700 北京中医药大学心血管研究所北京100700 北京中医药大学北京100029 中日友好医院北京100029

近年来,我国心血管疾病发病率和病死率仍在升高,疾病负担下降的拐点尚未出现。经皮冠状动脉介入(percutaneous coronary intervention,PCI)技术是治疗冠状动脉粥样硬化性心脏病的有效手段,其中药物洗脱支架及药物涂层球囊是目前临床中... 详细信息

近年来,我国心血管疾病发病率和病死率仍在升高,疾病负担下降的拐点尚未出现。经皮冠状动脉介入(percutaneous coronary intervention,PCI)技术是治疗冠状动脉粥样硬化性心脏病的有效手段,其中药物洗脱支架及药物涂层球囊是目前临床中最常用的2种PCI器械,但仍存在再狭窄及晚期血栓事件的问题。如何在保护内皮细胞活性的同时抑制血管平滑肌细胞增殖,进而既抑制再狭窄又抗血栓形成,是研究的热点及难点。中药单体及提取物尤其是中药单体组合涂层具有多靶点潜力,是对人工合成化合物涂层的重要补充。该文综述了应用于PCI器械药物涂层的中药单体(三氧化二砷、紫杉醇、水蛭素、川芎嗪、大黄素、苦参素、姜黄素等)、中药单体组合(紫杉醇/水蛭素、栀子苷/黄芩苷)、中药提取物(莪术提取物、昆明山海棠提取物),并对其中存在的问题及未来发展进行讨论,以期为研发新的PCI器械提供参考。

关键词：药物涂层中药支架球囊再狭窄支架血栓

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灵活性负荷参与电网调度的经济优化运行

科学技术与工程 2024年第7期24卷 2767-2774页

作者：崔喾张新燕何广渝王志磊王显岚张洪图新疆大学电气工程学院乌鲁木齐830047

在“碳达峰、碳中和”的背景下,大规模新能源并网使系统出现了调峰压力大、新能源消纳难等问题。随着灵活性负荷占比的不断增大,根据灵活性负荷的不同特性,针对系统面临的问题提出了“源-网-荷-储”相协调的双层优化运行模型。首先,基... 详细信息

在“碳达峰、碳中和”的背景下,大规模新能源并网使系统出现了调峰压力大、新能源消纳难等问题。随着灵活性负荷占比的不断增大,根据灵活性负荷的不同特性,针对系统面临的问题提出了“源-网-荷-储”相协调的双层优化运行模型。首先,基于分时电价策略引导用户用电行为,建立提升源荷双方综合满意度以及净负荷波动最小的上层多目标模型,利用粒子群算法对上层模型进行求解得到优化后的负荷需求响应并带入下层模型中。其次,根据源荷双方的供需关系,确定参与调度灵活负荷的运行方式,构建以系统调度运行成本最小为目标的下层模型,并采用Cplex求解器求解。最后,以某地区实际系统为例,结果表明了灵活性负荷参与电网调度可缓解电网调峰压力,提高了可再生能源消纳能力,并验证了本文所提模型的有效性。

关键词：分时电价策略灵活性负荷系统调度源-网-荷-储

Bursting behaviours in cascaded stimulated Brillouin scattering

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Chinese Physics B 2012年第1期21卷 310-313页

作者： Liu Zhan-Jun he xian-tu Zheng Chun-Yang Wang Yu-Gang Institute of Applied Physics and Computational Mathematics Beijing 100094China State Key Laboratory of Nuclear Physics and Technology Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China

Stimulated Brillouin scattering is studied by numerically solving the Vlasov Maxwell system. A cascade of stim- ulated Brillouin scattering can occur when a linearly polarized laser pulse propagates in a plasma. It is found that a stimulated Brillouin scattering cascade can reduce the scattering and increase the transmission of light, as well as intro- duce a bursting behaviour in the evolution of the laser-plasma interaction. The bursting time in the reflectivity is found to be less than half the ion acoustic period. The ion temperature can affect the stimulated Brillouin scattering cascade, which can repeat several times at low ion temperatures and can be completely eliminated at high ion temperatures. For stimulated Brillouin scattering saturation, higher-harmonic generation and wave wave interaction of the excited ion acoustic waves can restrict the amplitude of the latter. In addition, stimulated Brillouin scattering cascade can restrict. the amplitude of the scattered light.

关键词： bursting behaviour stimulated Brillouin scattering cascade

Dipole AlfvenVortex with Finite Ion Larmor Radius in a Low-Beta Plasma

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Chinese Physics Letters 2000年第7期17卷 517-518页

作者： WANG Xu-Yu he xian-tu LIU Zhen-Xing CAO Jin-Bin Institute of Applied Physics&Computational Mathematics Beijing 100088 Laboratory of Space Weather Center for Space Science&Applied ResearchChinese Academy of SciencesBeijing 100080

A set of nonlinear fluid equations which include the effects of ion gyroradius is derived to describe Alfven vortex. The correction of finite ion gyroradius to the Alfven vortex in the inertial region is much more significant than that in the kinetic region. The amplitude of the vortex is enhanced in both regions. The scale of the vortex in the kinetic region becomes larger whereas it becomes smaller in the inertial region.

关键词： vortex Radius radius

Design of an Indirect-Drive Pulse Shape for ~1.6 MJ Inertial Confinement Fusion Ignition Capsules

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Chinese Physics Letters 2014年第4期31卷 89-92页

作者： WANG Li-Feng WU Jun-Feng YE Wen-Hua FAN Zheng-Feng he xian-tu Institute of Applied Physics and Computational Mathematics Beijing 100094 heDPS Center for Applied Physics and Technology Peking Universir~y Beijing 100871

We present a design of indirect-drive pulse shape for inertial confinement fusion ignition capsules using laser energy 1.6 MJ with a moderate gain （~10） on the Shenguang 1V laser facility. The trade-off fuel compression （pressure） for resistance to the hydrodynamic instability （HI） in the recent high-foot （HF） implosion campaign [Dittrieh T t et al Phys. Rev. Lett. 112 （2014）055002] is recovered. The proposed design modifies the ＂main＂ pulse shape, which features a decompression-recompression step for the fuel shell resulting in higher areal density than that of the ＂simple＂ HF design, and thereby approaches the conditions required for ignition avoiding at the expense of more laser energy while holding the HI under control.

关键词： INERTIAL confinement fusion HYDRODYNAMICS DEUTERIUM TRITIUM SHOCK waves