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Seismic response of pile-supported structures considering the coupling of inertial and kinematic interactions in different soil sites

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FRONTIERS OF STRUCTURAL AND CIVIL ENGINEERING 2024年第9期18卷 1350-1361页

作者： Zhao, Huiling Zhang, fan Shanghai Univ Dept Civil Engn Shanghai 200444 Peoples R China

Dynamic soil-pile-superstructure interaction is crucial for understanding pile behavior in earthquake-prone ground. Evaluating the safety of piles requires determining the seismic bending moment caused by combined inertial and kinematic interactions, which is challenging. This paper addresses this problem through numerical simulations of piles in different soil sites, considering soil nonlinearity. Results reveal that the period of the soil site significantly affects the interaction among soil, piles, and structures. Bending moments in soft and hard soil sites exceed those in medium soil sites by more than twice. Deformation modes of piles exhibit distinct characteristics between hard and soft soil sites. Soft soil sites exhibit a singular inflection point, while hard soil sites show two inflection points. In soft soil sites, pile-soil kinematic interaction gradually increases bending moment from tip to head, with minor influence from superstructure's inertial interaction. In hard soil sites, significant inertial effects from soil, even surpassing pile-soil kinematic effects near the tip, lead to reversed superposition bending moment. Superstructure's inertial interaction notably impacts pile head in hard soil sites. A simplified coupling method is proposed using correlation coefficient to represent inertial and kinematic interactions. These findings provide insights into complex seismic interactions among soil, piles, and structures.

关键词： pile seismic response soft soil inertial interaction kinematic interaction PSEUDOSTATIC APPROACH STRUCTURE SYSTEMS CYCLIC MOBILITY BEHAVIOR MODEL

Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

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Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： Ning LI Pingzhi fan Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control

Effect of Incubation Temperature and Warming Solutions on the Viability and Maturation of Vitrified-thawed Human Immature Oocytes

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Journal of Reproduction and Contraception 2011年第2期22卷 65-74页

作者： Yu-ling HUANG Xiao-lin LONG Xiao-fang SUN Yong fan Hong-zi du Wen-hong ZHANG Yu SHI Li LI Han-yan LIU Reproductive Center of the Third Affiliated Hospital of Guangzhou Medical College Guangzhou 510150 China

Objective To investigate the viability and maturation of frozen-thawed human immature oocytes exposed to different temperature of vitrification and warming solutions. Methods The immature oocytes in germinal vesicle （GV） and matephase I （MI ） stages were collected from our ICSI patients and exposed to different temperature of vitrification and warming solutions before frozen in the freezing/thawing procedures. The different temperature groups were as follows： Group A, equilibration solution at 37℃, vitrification solution at room temperature, warming solution at 37℃; Group B, both vitrification and warming solution at room temperature; Group C, both vitrification and warming solutions at 37℃; Group D, the frozen-thawed oocytes and the fresh oocytes were cultured for in vitro maturation. The survival rate and maturation rate were compared among groups. The oocytes were examined using immunofluorescent stainingand confocal microscopy to check the spindle configuration and chromosome arrangement. Results The survival rates and MII rates of GV stage oocytes in groups A, B, C were 100%（15/15）, 81.3%（13/16）, 68.8%（11/16） and 33.3%（2/6）, 83.3%（10/12）,72.7%（8/11）, respectively. The survival rate of group C was significantly lower than that of the control （P〈0.05）. The normal spindle and chromosome configuration were only observed in group B, with the rates of 20% （2/20） and 10% （1/10）, respectively. The survival rates of MI stage in groups A, B, C were 71.4%（10/14）, 100% （12/12） and 83.3%（10/12）, no significantly difference from that of the contro1（100%, 14/14）. The MII rates of MI stage in groups A, B and C were 0%（0/14）, 66.7%（8/12） and 80% （8/10）, respectively. The MⅡ rate in group A was significantly lower than that in other groups （P〈0.01）. Only one oocyte in group C was found with normal spindle and chromosome configurations. Conclusion The appropriate operation temperature of vitrification and warming solutions can improve the outcomes of the vitrified-thawed human im

关键词： vitrification human immature oocytes spindle chromosome temperature

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有向动态网络中基于模体演化的链路预测方法

计算机应用研究 2019年第5期36卷 1441-1445,1453页

作者：杜凡刘群重庆邮电大学计算智能重庆市重点实验室

以往传统的链路预测方法大多数针对无向网络,而实际上大多数社交网络是有向的,并且没有考虑网络中同一节点对之间的重复边以及微观演化信息,因此不能较好地解决有向动态网络中的链路预测问题。针对有向网络,将节点对之间的重复边信息转... 详细信息

以往传统的链路预测方法大多数针对无向网络,而实际上大多数社交网络是有向的,并且没有考虑网络中同一节点对之间的重复边以及微观演化信息,因此不能较好地解决有向动态网络中的链路预测问题。针对有向网络,将节点对之间的重复边信息转换为该节点对之间连边的权值;接着采用了基于三元组模体的演化模型,对滑动窗口中相邻时间片的模体转换概率进行统计后,采用指数加权滑动平均法对其进行时序分析得到不同模体转换概率的预测矩阵,进而使用该矩阵对网络中的链边进行预测。这不仅充分利用了网络微观演化信息,而且解决了动态网络中重复边的问题。最后对实验结果进行分析发现,在高全局聚类系数高平均度的网络中AUC相比Triad Transition Matrix方法提高了近0.01,而相比CN方法提高更多。因此,所提方法能够较好地应用网络微观演化信息进行链路预测。

关键词：时序链路预测有向网络模体演化时序分析

坝面帷幕灌浆技术在竹银水库主坝坝基处理中的应用

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水利水电科技进展 2011年第6期31卷 55-58页

作者：曾凡杜中国水利水电第八工程局有限公司湖南长沙410007

针对竹银水库主坝坝基地质条件及工期紧张、基坑面临被暴雨淹没的实际情况,对河床坝基采取先进行坝体填筑、后在坝面进行帷幕灌浆基础处理的施工方法,并针对已填筑坝体、坝体与坝基接触段、基岩采取不同的技术措施,确保帷幕灌浆幕体与... 详细信息

针对竹银水库主坝坝基地质条件及工期紧张、基坑面临被暴雨淹没的实际情况,对河床坝基采取先进行坝体填筑、后在坝面进行帷幕灌浆基础处理的施工方法,并针对已填筑坝体、坝体与坝基接触段、基岩采取不同的技术措施,确保帷幕灌浆幕体与填筑坝体结合良好,形成完整的垂直防渗体系。该施工方法既解决了坝体填筑与基础处理的矛盾,又使工程得以安全度汛,使总体工期得到了保证,可供类似工程参考。

关键词：帷幕灌浆防渗坝基处理施工方案竹银水库

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黄河下游河道冲淤演变的分析

水资源保护 2005年第2期21卷 50-52,56页

作者：袁杜帆合肥工业大学土木建筑工程学院安徽合肥230009

从大量实测水文泥沙的观测资料出发,分析了黄河下游不同粒径泥沙的冲淤特性,讨论拦减粗沙及三门峡和小浪底水库修建后对下游河道冲淤的影响,给出近年来黄河下游河道冲淤的基本特性及其影响因素,提出了黄河下游减淤的一些措施,获得了一... 详细信息

从大量实测水文泥沙的观测资料出发,分析了黄河下游不同粒径泥沙的冲淤特性,讨论拦减粗沙及三门峡和小浪底水库修建后对下游河道冲淤的影响,给出近年来黄河下游河道冲淤的基本特性及其影响因素,提出了黄河下游减淤的一些措施,获得了一些有益的成果。

关键词：冲淤泥沙黄河下游含沙量

Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction:Efficient photodegradation of organic pollutant and toxicity evaluation

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Journal of Materials Science & Technology 2024年第3期170卷 200-211页

作者： Yanyan Zhao Xu fan Hongxing Zheng Enzhou Liu Jun fan Xuejun Wang College of Biology Pharmacy and Food Engineering Shangluo UniversityShangluo 726000China QinLing-Bashan Mountains Bioresources Comprehensive Development C.I.C. Shaanxi University of TechnologyHanzhong 723001China School of Chemical Engineering Northwest UniversityXi’an 710069China

Constructing of heterojunction was identified as a feasible way to improve photocatalytic activity of *** this work,a n-p type Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction was successfully prepared for organic pollutants *** Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction exhibited much higher pho-tocatalytic activity towards Rhodamine B(92.24%,expose to visible light for 60 min),norfloxacin(81.73%,expose to visible light for 90 min)and levofloxacin(87.46%,expose to visible light for 90 min)than pure Bi_(2)WO_(6)and pure AgInS_(2).Toxicity analysis indicated the low environmental toxicity of Rhodamine B degradation intermediates for Rye seeds and Sudangrass seeds germination and *** study displayed that AgInS_(2)and Bi_(2)WO_(6)work as the primary photocatalyst to form·O_(2)−and ·OH,*** improved photocatalytic activity of the Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction was due to the im-proved light response range and intensified carrier separation ***,a S-scheme charge transfer mechanism including multiple charge transfer channels was *** work could provide an effective strategy for organic pollutants degradation in wastewater.

关键词： Photocatalysis S-scheme heterojunction AgInS_(2) Bi_(2)WO_(6) Toxicity experiments

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大面积混凝土温度应力试验研究

混凝土 2016年第12期 130-133页

作者：杜帆杜红秀太原理工大学建筑与土木工程学院山西太原030024

为研究大面积混凝土的温度变形问题,针对地下车库底板和顶板掺与不掺密实剂的C40大面积混凝土,进行了弹性模量试验,利用振弦式应变计和热电偶进行了应变、温度现场实测,进行了温度应力分析。研究表明:混凝土弹性模量随着龄期的增长而增... 详细信息

为研究大面积混凝土的温度变形问题,针对地下车库底板和顶板掺与不掺密实剂的C40大面积混凝土,进行了弹性模量试验,利用振弦式应变计和热电偶进行了应变、温度现场实测,进行了温度应力分析。研究表明:混凝土弹性模量随着龄期的增长而增大;混凝土内部的应变均为膨胀,应变随着温度的降低而增大;掺入密实剂后应变显著减小;混凝土内部的应力均为膨胀压应力,比起不掺密实剂的混凝土,掺密实剂的混凝土压应力较小。

关键词：地下车库大面积混凝土密实剂应变温度应力

Soliton resolution and asymptotic stability of N-solutions for the defocusing Kundu–Eckhaus equation with nonzero boundary conditions

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Communications in Theoretical Physics 2024年第1期76卷 1-6页

作者： Engui fan Yanxi Zhang School of Mathematical Sciences and Key Laboratory of Mathematics for Nonlinear Science Fudan UniversityShanghai200433China Tianjin Xinhua High School No.99 machang RoadTianjin300204China

In this paper,we address interesting soliton resolution,asymptotic stability of N-soliton solutions and the Painleve asymptotics for the Kundu-Eckhaus(KE)equation with nonzero boundary conditions iq_(t)+q_(xx)-2(l|q|^(2)-1)q+4β^(2)(lql^(4)-1)q+4iβ(lql^(2))_(x)q=0,q(x,0)=q_(0)(x)-±1,x→±∞.The key to proving these results is to establish the formulation of a Riemann-Hilbert(RH)problem associated with the above Cauchy problem and find its connection with the RH problem of the defocusing NLS *** the■-steepest descent method and the results of the defocusing NLS equation,we find complete leading order approximation formulas for the defocusing KE equation on the whole(x,t)half-plane including soliton resolution and asymptotic stability of N-soliton solutions in a solitonic region,Zakharov-Shabat asymptotics in a solitonless region and the Painlevéasymptotics in two transition regions.

关键词： defocusing Kundu-Eckhaus equation Riemann-Hilbert problems steepest descent method soliton resolution asymptotic stability Painleve transcendents