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Collisional Penrose process of 4D rotational Einstein-Gauss-Bonnet black holes

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Chinese Physics C 2021年第5期45卷 212-222页

作者： yunlong liu Xiangdong Zhang Department of Physics South China University ofTechnologyGuangzhou 510641China

The collisional Penrose process of massive spinning particles in a rotational Einstein-Gauss-Bonnet(EGB) black hole background is studied. By numerically solving the equations of motion for spinning particles, we find that the energy extraction efficiency increases monotonically with the decrease of the EGB coupling parameterα. Moreover, the efficiency η increases as the particle spin s grows. We also find that the energy extraction efficiency increases with the decrease of the EGB coupling parameter α. When the EGB coupling constant α = 0, our results reduce to the Kerr case, which has been investigated previously.

关键词： Penrose process Gauss Bonnet gravity particle collision

Artificial seed germination and seedling production of Zostera marina *** salinity manipulation

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Acta Oceanologica Sinica 2016年第8期35卷 99-105页

作者： liu yunlong ZHANG Xuelei SONG Wei WANG Zongling College of Environmental Science and Engineering Ocean University of China Key Laboratory of Science and Engineering for Marine Ecology and Environment State Oceanic Administration The First Institute of Oceanography State Oceanic Administration

Vast declines in Zostera marina seagrass beds demand effective methods of rehabilitation. In this study, we developed a practical method by reducing salinity to induce seed germination followed with recovering salinity to facilitate seedling production of Z. marina. The results showed that Z. marina seeds collected from natural seawater（salinity 30） were induced to germinate at reduced salinities. Percent germination（GR） was higher and mean-time-to-germinate（MTG） was shorter at lower salinities. The highest GR and shortest MTG occurred at salinity 0（deionized freshwater）. After germination in freshwater, seeds could develop into seedlings at salinities5–30 and continue the growth. Viability or development of germinated seeds was not significantly different during the 40 d of post-germination incubation at salinities 5–15 after 1–20 d of germination in freshwater. However,during the process of translating germinated seeds from salinity 0 and 5 to salinity 30, reducing the gradients of post-germination acclimation facilitated more seeds forming seedlings in less time. On average, after 60 d of static incubation, including 20 d in freshwater for germination followed with immediate shift to salinity 5 and increasing to salinity 30 at increment of 5 every two days until cultivation at constant salinity 30, 33% of Z. marina seeds produced healthy seedlings. The results indicate that the salinity-manipulation based method of artificial germination and seedling production is practical and effective in supporting rehabilitation of Z. marina bed.

关键词： Zostera marina L. rehabilitation seed germination seedling salinity

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地震波斜入射作用下重力坝地震响应分析

三峡大学学报（自然科学版） 2024年第1期46卷 14-22页

作者：陈灯红曾怡阳赵艺园刘云龙岳梦防灾减灾湖北省重点实验室(三峡大学) 湖北宜昌443002 三峡大学土木与建筑学院湖北宜昌443002

为了研究地震波斜入射作用下重力坝的地震响应,本文基于黏弹性边界及相应的地震动输入方法,分别推导了P波和SV波倾斜入射时的等效地震力,构建了考虑地震波斜入射的黏弹性静-动力统一型人工边界.以黄登混凝土坝为研究对象,研究了P波和SV... 详细信息

为了研究地震波斜入射作用下重力坝的地震响应,本文基于黏弹性边界及相应的地震动输入方法,分别推导了P波和SV波倾斜入射时的等效地震力,构建了考虑地震波斜入射的黏弹性静-动力统一型人工边界.以黄登混凝土坝为研究对象,研究了P波和SV波在不同斜入射角度下混凝土坝的地震响应,重点分析了重力坝在地震作用下的水平、竖直相对位移与主应力.研究结果表明:混凝土重力坝的地震响应中在斜入射情况下P波与SV波有明显的差异,考虑地震波的斜入射很有必要;P波斜入射时,随着入射角度的增加,坝体关键点的水平、竖直相对位移与主应力值逐渐增加(60°时达到最大);SV波斜入射时随着角度的增加关键点相对位移与坝体主应力变化不大,但整体来看入射角度为0°时(即垂直入射)与其他入射角度相比无论是竖直、水平相对位移或坝体关键点主应力均为最大.

关键词：黏弹性边界斜入射重力坝地震响应地震动输入

河北省农灌机井“以电折水”计量体系建设与应用

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中国水利 2024年第1期 48-51页

作者：刘淼侯爽康之增刘云龙河北省水利科学研究院石家庄050057 河北工程大学水利水电学院邯郸056009 河北省水资源研究与水利技术试验推广中心石家庄050061 国网河北省电力有限公司石家庄050057

农业灌溉用水计量问题是取用水监管的重要内容之一。为适应北方地区农业灌溉机井“点多、面广、产权分散”的分布特点,河北省积极探索并形成了农灌机井“以电折水”计量体系。介绍了“以电折水”计量的理论基础和河北省“以电折水”计... 详细信息

农业灌溉用水计量问题是取用水监管的重要内容之一。为适应北方地区农业灌溉机井“点多、面广、产权分散”的分布特点,河北省积极探索并形成了农灌机井“以电折水”计量体系。介绍了“以电折水”计量的理论基础和河北省“以电折水”计量体系建设历程,提出了河北省“以电折水”计量体系的框架、内涵解读、业务应用场景,以及未来发展建议。

关键词：农灌机井以电折水计量建设与应用河北省

Differential Splicing of Skipped Exons Predicts Drug Response in Cancer Cell Lines

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Genomics, Proteomics & Bioinformatics 2021年第6期19卷 901-912页

作者： Edward Simpson Steven Chen Jill L.Reiter yunlong liu Center for Computational Biology and Bioinformatics Indiana University School of MedicineIndianapolisIN 46202USA Department of BioHealth Informatics School of Informatics and ComputingIndiana University-Purdue University IndianapolisIndianapolisIN 46202USA Department of Medical and Molecular Genetics Indiana University School of MedicineIndianapolisIN 46202USA

Alternative splicing of pre-mRNA transcripts is an important regulatory mechanism that increases the diversity of gene products in *** studies have linked specific transcript isoforms to altered drug response in cancer;however,few algorithms have incorporated splicing information into drug response *** this study,we evaluated whether basal-level splicing information could be used to predict drug sensitivity by constructing doxorubicin-sensitivity classification models with splicing and expression *** detailed splicing differences between sensitive and resistant cell lines by implementing quasi-binomial generalized linear modeling(QBGLM)and found altered inclusion of 277 skipped *** additionally conducted RNA-binding protein(RBP)binding motif enrichment and differential ex-pression analysis to characterize cis-and trans-acting elements that potentially influence doxorubicin response-mediating splicing *** results showed that a classification model built with skipped exon data exhibited strong predictive *** discovered an association between differentially spliced events and epithelial-mesenchymal transition(EMT)and observed motif enrichment,as well as differential expression of RBFOX and ELAVL RBP family *** work demonstrates the potential of incorporating splicing data into drug response algorithms and the utility of a QBGLM approach for fast,scalable identification of relevant splicing differences between large groups of samples.

关键词： Alternative splicing Transcript isoform Splicing regulation Drug sensitivity Precision medicine

Energy conditions in the new model of loop quantum cosmology

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Chinese Physics C 2021年第11期45卷 143-150页

作者： Gaoping Long yunlong liu Xiangdong Zhang Department of Physics South China University of TechnologyGuangzhou 510641China Department of Physics Beijing Normal UniversityBeijing 100875China

Recently,a de-Sitter epoch has been found in the new model of loop quantum cosmology,which is governed by the scalar constraint with both Euclidean and Lorentz *** singularity free bounce in the new LQC model and the emergent cosmology constant strongly suggest that the effective stress-energy tensor induced by quantum corrections must violate the standard energy *** this study,we perform an explicit calculation to analyze the behaviors of specific representative energy conditions,i.e.,average null,strong,and dominant energy *** reveal that the average null energy condition is violated at all times,while the dominant energy condition is violated only at a period around the bounce *** strong energy condition is violated not only at a period around the bounce point but also in the whole period from the bounce point to the classical phase corresponding to the de Sitter *** results will shed some light on the construction of a wormhole and time machine,which usually require exotic matter to violate energy conditions.

关键词： energy condition loop quantum cosmology quantum gravity

Dynamic Response of Floating Body Subjected to Underwater Explosion Bubble and Generated Waves with 2D Numerical Model

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Computer Modeling in Engineering & Sciences 2019年第2期118卷 397-423页

作者： Zhaoli Tian yunlong liu Shiping Wang A Man Zhang Youwei Kang College of Shipbuilding Engineering Harbin Engineering UniversityHarbinHeilongjiangChina Division of Applied Mathematics Brown UniversityProvidence RI 02912USA CIMC Offshore Co.Ltd. YantaiShandongChina.

The low frequency load of an underwater explosion bubble and the generated waves can cause significant rigid motion of a ship that threaten its *** order to study the fluid-structure interaction qualitatively,a two-dimensional underwater explosion bubble dynamics model,based on the potential flow theory,is established with a double-vortex model for the doubly connected bubble dynamics simulation,and the bubble shows similar dynamics to that in 3-dimensional domain.A fully nonlinear fluid-structure interaction model is established considering the rigid motion of the floating body using the mode-decomposition *** test of the model is implemented by simulating the free rolling motion of a floating body in still *** the simulation of the interaction of the underwater explosion bubble,the generated waves and the floating body based on the presented model,the influences of the buoyancy parameter and the distance parameter are *** is found that the impact loads on floating body caused by underwater explosion bubble near the free surface can be divided into 3 components:bubble pulsation,jet impact,and slamming load of the generated waves,and the intensity of each component changes nonlinearly with the buoyance *** bubble pulsation load decays with the increase in the horizontal ***,the impact load from the generated waves is not monotonous to *** increases with the distance within a particular distance threshold,but decays thereafter.

关键词： Underwater explosion bubble dynamics fluid-structure interaction double-vortex model waves generated by underwater explosion.

Variance-Constrained Control for Uncertain Stochastic Systems via Disturbance Observers

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Variance-Constrained Control for Uncertain Stochastic System...

第36届中国控制会议

作者： yunlong liu Ping Zhou Mingzhi liu Key Laboratory of Integrated Automation for Process Industry Ministry of EducationNortheastern University Tianjin Airlines Company Limited

ISBN: (纸本)9781538629185

In this paper, the robust variance-constrained composite control problem is investigated for linear uncertain discretetime stochastic systems. The parameter uncertainties are allowed to be norm-bounded and enter into the state matrix. The purpose of this problem is to design a disturbance observer to estimate the disturbance generated by an exogenous system, then construct the control strategy by integrating the output of the disturbance observer with state-feedback control law, such that, for all admissible parameter uncertainties, the system state of the closed-loop system is mean square bounded, and the steady state variance of each state is not more than the individual prescribed upper bound. And a LMI method is developed to deal with the control problem, which is related to a linear matrix inequality. An illustrative numerical example is provided to demonstrate the effectiveness of the proposed design approach.

关键词： Stochastic System Variance Constraint Disturbance Observer Composite Control

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特急曲线水利隧洞针梁台车设计与施工

施工技术（中英文） 2024年第8期53卷 54-59页

作者：刘翔刘云龙魏波汤宇尹来容童昌中铁五局集团第一工程有限责任公司湖南长沙410117 长沙理工大学汽车与机械工程学院湖南长沙410114

水利基础设施建设过程中,特急曲线水利隧洞具有弯多、弯急的特点。普通针梁台车在此类隧洞工程施工中,出现弯道碰壁、受压变形等诸多问题,传统施工装备与技术的适应性难题亟待解决。以金沙江向家坝灌区北总干渠一期工程望江岩隧洞衬砌... 详细信息

水利基础设施建设过程中,特急曲线水利隧洞具有弯多、弯急的特点。普通针梁台车在此类隧洞工程施工中,出现弯道碰壁、受压变形等诸多问题,传统施工装备与技术的适应性难题亟待解决。以金沙江向家坝灌区北总干渠一期工程望江岩隧洞衬砌施工为依托,在传统全圆针梁台车既有设计方法的基础上,开展加大单次衬砌长度、整体快速拆合、优化结构形式、改变脱模方式、实现高通用性等方面研究;研制特急曲线水利隧洞全圆针梁台车,创新台车不同状态下的施工工法,解决了台车在曲线处行走时会触碰隧洞壁,台车过特急曲线隧洞需重复拆卸及安装,衬砌完成后上、下侧模在受力状态下出现模板反向咬合等问题,有效推动了特急曲线隧洞施工装备设计方法革新。实际应用结果表明,所开发的特急曲线水利隧洞全圆针梁台车及其相关施工技术大幅度提高了特急曲线水利隧洞施工效率,降低了施工成本,保证了施工安全和工程质量。

关键词：水利工程隧洞台车模板设计施工技术