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Research in Astronomy and Astrophysics 2024年第8期24卷 32-41页

作者： Yingze Shan Xiaoxuan liu Xing Yang Haoyu Yuan houjun lü Guangxi Key laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China

Theoretically,a supra-massive neutron star or magnetar may be formed after the merger of binary neutron ***210323A is a short-duration gamma-ray burst(GRB)with a duration of lasting~1 *** light curve of the prompt emission of GRB 210323A shows a signal-peaked structure and a cutoff power-law model can adequately fit the spectra with E_p=1826±*** interestingly,it has an extremely long-lasting plateau emission in the X-ray afterglow with a duration of~10^(4)s,and then follows a rapid decay with a decay slope~*** temporal feature is challenging by invoking the external shock *** this paper,we suggest that the observed long-lasting X-ray plateau emission is caused by the energy injection of dipole radiation from supra-massive magnetar,and the abrupt decay following the longlasting X-ray plateau emission is explained by supra-massive magnetar collapsing into a black *** is the short GRB(SGRB)with the longest X-ray internal plateau emission powered by a supra-massive neutron *** this is the case,one can estimate the physical parameters of a supra-massive magnetar,and compare with other *** also discuss the possible gravitational-wave emission,which is powered by a supra-massive magnetar and its detectability,and the possible kilonova emission,which is powered by r-process and magnetar spin-down to compare with the observed data.

关键词： (stars)gamma-ray burst general-(stars)gamma-ray burst individual(GRB 210323A)-stars magnetars

Transfer matrix method for free and forced vibrations of multi-level functionally graded material stepped beams with different boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 983-1000页

作者： Xiaoyang SU Tong HU Wei ZHANG houjun KANG Yunyue CONG Quan YUAN School of Civil Engineering and Architecture Guangxi UniversityNanning 530004China Scientific Research Center of Engineering Mechanics Guangxi UniversityNanning 530004China State Key laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Guangxi UniversityNanning 530004China

Functionally graded materials(FGMs)are a novel class of composite materials that have attracted significant attention in the field of engineering due to their unique mechanical *** study aims to explore the dynamic behaviors of an FGM stepped beam with different boundary conditions based on an efficient solving *** the assumptions of the Euler-Bernoulli beam theory,the governing differential equations of an individual FGM beam are derived with Hamilton’s principle and decoupled via the separation-of-variable ***,the free and forced vibrations of the FGM stepped beam are solved with the transfer matrix method(TMM).Two models,i.e.,a three-level FGM stepped beam and a five-level FGM stepped beam,are considered,and their natural frequencies and mode shapes are *** demonstrate the validity of the method in this paper,the simulation results by ABAQUS are also *** this basis,the detailed parametric analyses on the frequencies and dynamic responses of the three-level FGM stepped beam are carried *** results show the accuracy and efficiency of the TMM.

关键词： transfer matrix method(TMM) free vibration forced vibration functionally graded material(FGM) stepped beam

Distributed Secondary Control Based on Dynamic Diffusion Algorithm for Current Sharing and Average Voltage Regulation in DC Microgrids

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 597-607页

作者： Dawei liao Fei Gao Daniel J.Rogers Wentao Huang Dong liu houjun Tang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Engineering Science University of OxfordOxford OX12JDU.K. IEEE

This paper introduces a distributed secondary control scheme for achieving current sharing and average voltage regulation objectives in a DC *** proposed scheme employs a dynamic diffusion algorithm(DDA)instead of the consensus algorithm to enable distributed communication among *** help understand DDA,the relation of DDA and other diffusion algorithms is discussed in detail and its superiority is shown by comparison with diffusion and consensus ***,considering the discrete nature and different sampling time of the digital controller and communication network,a z-domain model of the entire DC microgrid is *** influence of communication and secondary control parameters on the system stability is *** on the established model,the tolerable communication rates are ***-time simulations conducted on the OPAl-RT platform validate the effectiveness of the proposed scheme,showcasing its advantages in terms of convergence speed and stability.

关键词： Cooperative control DC microgrid diffusion algorithm discrete-time modeling distributed secondary control

Reconstruction using artificial intelligence,a promising way to explore the cosmic web

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 179-179页

作者： houjun Mo Department of Astronomy University of MassachusettsAmherst MA 01003USA

One of the most important goals in modern cosmology is to understand the large-scale mass distribution of the universe(the cosmic web),and how galaxies form and evolve in the ecosystem of the cosmic *** this is done by large redshift surveys of galaxies,which can be used to trace the large-scale structure and to sample the properties of galaxies.

关键词： galaxies cosmic universe

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省属高校仪器设备政府采购的实践与探索

实验技术与管理 2010年第12期27卷 224-227页

作者：吕厚均黑龙江大学资产管理处

从回顾政府采购的概念、组织形式和采购方式入手,简述了政府采购制度的产生及黑龙江省政府采购的现状,提出了构建省属高校仪器设备政府采购模式,介绍了黑龙江大学加强仪器设备政府采购工作的具体措施及成效。

关键词：政府采购设备采购地方高校

Cold gas contents of galaxies and their relations to the stellar and dark-matter components

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 180-180页

作者： houjun Mo Department of Astronomy University of MassachusettsAmherst MA 01003USA

One of the most important goals of modern cosmology is to understand how galaxies form and evolve in ecosystems defined by the cosmic density field. The formation of galaxies is a process through which cold baryonic g... 详细信息

关键词： galaxies stellar stars

同方期刊数据库

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浅谈高支模技术在工程中的应用

城市建筑 2014年第30期11卷 84-85页

作者：吕厚俊南通华新建工集团有限公司南通226600

本文论述了高支模施工技术的施工的方法。在实际应用中严格按设计方案施工，取得了理想的效果。

关键词：高支撑间距剪刀撑跨度

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深基坑综合围护施工技术

城市建筑 2014年第30期11卷 81-82,120页

作者：吕厚俊南通华新建工集团有限公司

太仓市文化艺术中心项目基坑开挖最大深度为14.1 m。浅基坑采用土钉墙支护，深基坑采用钻孔灌注桩加一道混凝土支撑，在灌注桩外侧施工一排旋喷桩作为防渗止水帷幕，基底采用深井降水。结果表明，该围护设计及施工安全、经济。

关键词：基坑支护灌注桩旋喷桩止水帷幕混凝土支撑

数字示波器中FPGA间高速信号传输同步方法

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电子科技大学学报 2024年第2期53卷 219-226页

作者：高媛赵禹王厚军叶芃军委装备发展部北京100034 电子科技大学(深圳)高等研究院深圳518110

数据采集系统是数字示波器(DSO)的核心组成单元,随着示波器带宽采样率的逐步提升,单片模数转换器(ADC)+现场可编辑门控阵列(FPGA)的架构难以满足超高速以及多通道的应用场景,因此,高端示波器中数据采集系统普遍采用“主从”FPGA控制架... 详细信息

数据采集系统是数字示波器(DSO)的核心组成单元,随着示波器带宽采样率的逐步提升,单片模数转换器(ADC)+现场可编辑门控阵列(FPGA)的架构难以满足超高速以及多通道的应用场景,因此,高端示波器中数据采集系统普遍采用“主从”FPGA控制架构。在该架构下,多个FPGA之间信号的同步传输是实现采集系统的同步和精确采集的重要前提。针对多FPGA板卡之间的信号同步传输问题,提出了一种FPGA之间高速信号同步传输的方法,借助FPGA的IODElAY单元,通过测试数据训练找到最稳定的同步传输区间,实现多FPGA之间的同步传输。在自研的数字示波器上的实验表明,该方法能够有效实现FPGA之间高速信号的同步传输。

关键词：超高速数据采集系统现场可编辑门控阵列传输同步数字存储示波器

美联储加息冲击下跨境资本流动监管的“双支柱”调控研究

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国际金融研究 2024年第3期 76-86页

作者：胡小文项后军安徽师范大学经济管理学院广东金融学院金融与投资学院

后疫情时代美国超宽松货币政策导致其通胀高企,美联储开启史诗级加息周期,国际资本大幅快速回流美国,导致全球金融风险显著上升,人民币汇率波动加剧,亟须加强跨境资本流动的宏观审慎监管。本文构建一个包含无息外汇准备金逆周期调节跨... 详细信息

后疫情时代美国超宽松货币政策导致其通胀高企,美联储开启史诗级加息周期,国际资本大幅快速回流美国,导致全球金融风险显著上升,人民币汇率波动加剧,亟须加强跨境资本流动的宏观审慎监管。本文构建一个包含无息外汇准备金逆周期调节跨境资本流动的小型开放动态随机一般均衡框架,研究“双支柱”调控应对美联储加息冲击的效果。结果表明:第一,美联储加息冲击下,国内产出和通胀下滑,人民币贬值;此时采取降低外汇存款准备金政策能稳定汇率并降低经济波动,主要机制是下调外汇存款准备金能增加国内金融机构外汇贷款的资金供给,降低国内企业融资成本。第二,提升利率政策虽然有助于稳定汇率,但会增大经济波动且削弱货币政策有效性;而“双支柱”调控不仅能降低产出和汇率波动,还不会降低货币政策有效性。第三,“双支柱”政策最优组合是货币政策盯住国内产出和通胀波动,宏观审慎政策盯住国际资本流动。据此,本文认为,我国应采用“双支柱”调控应对美联储激进加息,降低利率以应对通胀和产出下滑,降低外汇存款准备金率以促进汇率稳定。

关键词：美联储加息跨境资本流动双支柱动态随机一般均衡