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Analysis of Snow Distribution and Displacement in the Bogie Region of a High-Speed Train

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1687-1701页

作者： zhihui du Mengge Yu Jiali Liu Xiulong Yao College of Mechanical and Electrical Engineering Qingdao UniversityQingdao266071China National Engineering Research Center for High-Speed EMU CRRC Qingdao Sifang Co.Ltd.Qingdao266111China

Snow interacting with a high-speed train can cause the formation of ice in the train bogie region and affect its *** this study,a wind-snow multiphase numerical approach is introduced for high-speed train bogies on the basis of the Euler-Lagrange discrete phase model.A particle-wall impact criterion is implemented to account for the presence of snow particles on the ***,numerical simulations are conducted,considering various snow particle diameter distributions and *** research results indicate that when the particle diameter is relatively small,the distribution of snow particles in the bogie cavity is relatively ***,as the particle diameter increases,the snow particles in the bogie cavity are mainly located in the rear wheel pairs of the *** the more realistic Rosin-Rammler diameter distribution is applied to snow particles,the positions of snow particles with different diameters vary in the bogie *** precisely,smaller diameter particles are primarily located in the front and upper parts of the bogie cavity,while larger diameter snow particles accumulate at the rear and in the lower parts of the bogie cavity.

关键词： Bogie the wind-snow multiphaseﬂow model particle diameter distribution

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仿真网格中一种基于知识的动态任务调度算法

计算机研究与发展 2008年第2期45卷 261-268页

作者：吴磊都志辉清华大学计算机科学与技术系北京100084

仿真网格是以通用网格技术为基础、面向仿真领域的专用网格,目前国际上对仿真网格的研究尚处于起步阶段.现有的分布式仿真HLA(highlevel architecture)体系结构中的仿真资源和联邦成员是静态绑定的,网格技术的引入使得仿真资源的动态分... 详细信息

仿真网格是以通用网格技术为基础、面向仿真领域的专用网格,目前国际上对仿真网格的研究尚处于起步阶段.现有的分布式仿真HLA(highlevel architecture)体系结构中的仿真资源和联邦成员是静态绑定的,网格技术的引入使得仿真资源的动态分配成为可能.根据仿真网格任务调度的特点,在仿真网格中建立了一种任务调度模型,并针对该模型,提出了一种新的基于知识的动态任务调度算法KMO,该算法适用于将N个相互独立的计算需求不同的仿真任务调度到M个随时间动态变化的仿真资源上,它能对若干次调度后的结果进行统计并提炼成"知识"反馈给算法预处理部分,使得该算法在动态多变的环境中能获得比较稳定的性能.实验结果表明,在仿真网格环境中,该算法的性能优于网格中传统的任务调度算法.

关键词：网格仿真网格任务调度 RR KMO

Gravitational wave astrophysics, data analysis and multimessenger astronomy

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Science China(Physics,Mechanics & Astronomy) 2015年第12期58卷 44-64页

作者： LEE Hyung Mok LE BIGOT Eric-Olivier du zhihui LIN ZhangXi GUO XiangYu WEN LinQing PHUKON Khun Sang PANDEY Vihan BOSE Sukanta FAN Xi-Long HENDRY Martin Department of Physics and Astronomy Seoul National University Research Institute of Information Technology Tsinghua National Laboratory for Information Science and TechnologyTsinghua University Laboratoire Astro Particule et Cosmologie (APC) Universit Paris Diderot-Paris 7 Bc/timent Condorcet Case 7020 75205 Paris Cedex 13 France Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and TechnologyTsinghua University School of Physics The University of Western Australia Department of Physics IIT Kanpur Inter-University Centre for Astronomy and Astrophysics Department of Physics & Astronomy Washington State University School of Physics and Electronics Information Hubei University of Education SUPA School of Physics and Astronomy University of Glasgow

This paper reviews gravitational wave sources and their detection. One of the most exciting potential sources of gravitational waves are coalescing binary black hole systems. They can occur on all mass scales and be formed in numerous ways, many of which are not understood. They are generally invisible in electromagnetic waves, and they provide opportunities for deep investigation of Einstein's general theory of relativity. Sect. 1 of this paper considers ways that binary black holes can be created in the universe, and includes the prediction that binary black hole coalescence events are likely to be the first gravitational wave sources to be detected. The next parts of this paper address the detection of chirp waveforms from coalescence events in noisy *** analysis is computationally intensive. Sect. 2 reviews a new and powerful method of signal detection based on the GPUimplemented summed parallel infinite impulse response filters. Such filters are intrinsically real time alorithms, that can be used to rapidly detect and localise signals. Sect. 3 of the paper reviews the use of GPU processors for rapid searching for gravitational wave bursts that can arise from black hole births and coalescences. In sect. 4 the use of GPU processors to enable fast efficient statistical significance testing of gravitational wave event candidates is reviewed. Sect. 5 of this paper addresses the method of multimessenger astronomy where the discovery of electromagnetic counterparts of gravitational wave events can be used to identify sources, understand their nature and obtain much greater science outcomes from each identified event.

关键词： gravitational waves data analysis multimessenger

Reconstruction algorithm of super-resolution infrared image based on human vision processing mechanism

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Frontiers of Optoelectronics 2015年第2期8卷 195-202页

作者： Shaosheng DAI zhihui du Haiyan XIANG Jinsong LIU Chongqing Key Laboratory of Signal and Information Processing Chongqing University of Posts and Telecommunications Chongqing 400065 China

Aiming at solving the problem of low resolu- tion and visual blur in infrared imaging, a super-resolution infrared image reconstruction method using human vision processing mechanism （HVPM） was proposed. This method combined a mechanism of vision lateral inhibition with an algorithm projection onto convex sets （POCS） reconstruction, the improved vision lateral inhibition network was utilized to enhance the contrast between object and background of low-resolution image sequences, then POCS algorithm was adopted to reconstruct super- resolution image. Experimental results showed that the proposed method can significantly improve the visual effect of image, whose contrast and information entropy of reconstructed infrared images were improved by approxi- mately 5 times and 1.6 times compared with traditional POCS reconstruction algorithm, respectively.

关键词： human vision processing mechanism(HVPM) projection onto convex sets (POCS) super-resolution infrared image reconstruction algorithm

Modern Literature Research on Children Sweat Syndrome based on TF-IDF

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Journal of Clinical and Nursing Research 2022年第2期6卷 15-21页

作者： Hongli Luo Jiangwei Yu zhihui du Shiyu Tan Guizhou University of Traditional Chinese Medicine Guiyang 550025China

Objective:To explore the characteristics of intelligent syndrome diagnosis and intelligent syndrome differentiation of pediatric sweat syndrome by retrospectively studying the traditional Chinese medicine(TCM)-based diagnosis and rule of drug use on pediatric sweat syndrome in China Academic Journal Full-text Database(CNKI),Wanfang Database(WF)and VIP ***:Modern literature on pediatric sweat syndrome was collected with Endnote software,and the collected data were input into The Microsoft Excel 2010 ***-IDF relative entropy quantitative analysis was used to extract the intelligent diagnosis and intelligent medication rule of pediatric sweat syndrome in modern ***:TF-IDF was used to obtain the syndrome’s type-symptom fuzzy matrix and syndrome’s type-TCM fuzzy matrix of qi-yin deficiency and ***:The intelligent syndrome diagnosis and intelligent syndrome differentiation law of modern data mining in the treatment of children sweat syndrome accord with the basic theory of TCM,and can provide clinical reference to a certain extent.

关键词： Children sweat syndrome TF-IDF Medication rule Data mining

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数值相对论与引力波天文学

中国科学：物理学、力学、天文学 2017年第1期47卷 55-72页

作者：曹周键都志辉中国科学院数学与系统科学研究院北京100190 清华大学计算机科学与技术系北京100084

引力波直接探测已经被LIGO成功实现.在这个重大实验发现中,理论模型的重要作用得到充分体现.有效单体数值相对论模型不仅提升了既定硬件的灵敏度,把实验结果的置信度从4.6σ加强到5.1σ,而且还辨认出该引力波源是并合双黑洞.以这次实验... 详细信息

引力波直接探测已经被LIGO成功实现.在这个重大实验发现中,理论模型的重要作用得到充分体现.有效单体数值相对论模型不仅提升了既定硬件的灵敏度,把实验结果的置信度从4.6σ加强到5.1σ,而且还辨认出该引力波源是并合双黑洞.以这次实验结果所给出的双星并合事件率推断,地面引力波探测器接下来还会给出更多的引力波事件.这些引力波实验数据可以被用来进行天文学和基本物理学的研究.随着数据的积累和新脉冲星的加入,脉冲星计时计划的引力波探测精度也越来越高.空间引力波探测计划包括eLISA、太极和天琴等也在积极准备中.可以预期,引力波天文学将逐渐形成.在引力波天文学中,从信号读取到参数反演都离不开理论模型.不做任何解析近似的数值相对论是现实引力波源建模的通用工具.爱因斯坦方程的复杂数学结构和所需的庞大程序构架是数值相对论的两大困难.结合引力波天文学,本文对数值相对论的关键困难、发展历程、研究现状和在引力天文学中的应用等给出比较系统的描述.

关键词：数值相对论引力波天文学爱因斯坦方程匹配滤波方法

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GPU支持的低延迟引力波数据处理

中国科学：物理学、力学、天文学 2017年第1期47卷 73-85页

作者：都志辉温琳清清华大学计算机系清华信息科学与技术国家实验室北京100084 西澳大利亚大学物理系澳大利亚帕斯6009

只有快速识别出引力波信号,才可以制导电磁望远镜及时探测到相关的电磁信号,对于全面了解引力波源所发生的天体物理过程,具有十分重要的科学意义.本文针对在激光干涉引力波天文台(Laser Interferometer Gravitational-Wave Observatory,... 详细信息

只有快速识别出引力波信号,才可以制导电磁望远镜及时探测到相关的电磁信号,对于全面了解引力波源所发生的天体物理过程,具有十分重要的科学意义.本文针对在激光干涉引力波天文台(Laser Interferometer Gravitational-Wave Observatory,LIGO)在线运行的并行求和无限冲击响应滤波(Summed Parallel Infinite Impulse Response,SPIIR)流水线数据处理系统,具体介绍了如何在图形处理单元(Graphics Processing Unit,GPU)上采用多种性能优化手段,大幅度提高其数据处理的速度来满足LIGO低延迟实时数据处理的要求.并进一步描述了如何在高新LIGO(Advanced LIGO)基础上实现极低延迟数据处理的计算方法、性能优化方法与相关的工具支持.

关键词：引力波数据处理并行计算图形处理单元

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基于IA-64的虚拟接口结构设计

清华大学学报（自然科学版） 2006年第4期46卷 576-579页

作者：杨丰都志辉唐瑞春清华大学计算机科学与技术系北京100084

针对IA-64平台地址空间和数据空间的特点,该文给出一种简单有效的地址转换与数据表示方法,在此基础上提出可以有效保持虚拟接口结构(v irtua l in terfacearch itecture,V IA)各层抽象描述与具体实现相一致的设计方案。在自主研制的V I... 详细信息

针对IA-64平台地址空间和数据空间的特点,该文给出一种简单有效的地址转换与数据表示方法,在此基础上提出可以有效保持虚拟接口结构(v irtua l in terfacearch itecture,V IA)各层抽象描述与具体实现相一致的设计方案。在自主研制的V IA通信硬件基础上,实现了一个软硬件有机结合的实例THV IA 64。测试结果表明THV IA 64不仅可以稳定运行,而且具有很高的通信性能,8 B延迟为9μs,最大带宽为119 M B/s。对比数据表明V IA在IA-64平台上可以展示出更好的性能。

关键词：虚拟接口结构(VIA) 用户层通信机群 IA-64

基于OGSA标准的发票数据库网格IDBGrid的设计与实现

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计算机工程与应用 2005年第22期41卷 197-201页

作者：史隆都志辉清华大学计算机科学与技术系北京100084

该文根据OGSA标准提出将分布于全国各地的成千发票数据库虚拟化,通过对原系统的重新规划与设计,建成一个具有超强的存储和运算能力的发票数据库网格IDBGrid,IDBGrid在Web服务资源框架基础上提供网格数据库管理系统注册服务、网格数据库... 详细信息

该文根据OGSA标准提出将分布于全国各地的成千发票数据库虚拟化,通过对原系统的重新规划与设计,建成一个具有超强的存储和运算能力的发票数据库网格IDBGrid,IDBGrid在Web服务资源框架基础上提供网格数据库管理系统注册服务、网格数据库管理服务、网格数据服务、网格数据库复制服务、网格数据库监控服务、网格数据库故障转移服务等,提供一个统一、透明的数据库网格访问和整合界面,通过网格环境下数据库服务器之间的协同处理达到提高资源利用率、运行性能,降低开发和维护成本,增强系统健壮性和可用性的目的,文章重点研究了异构环境下数据库管理系统的网格化管理的关键技术。

关键词：数据库网格开放网格体系结构 Web服务资源框架