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UAV-Assisted FSO Communication System with Amplify-and-Forward Protocol under AOA Fluctuations:A Performance Analysis

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China Communications 2023年第11期20卷 111-130页

作者： Maozhe Xu Guanjun Xu Youran Dong Weizhi Wang Qinyu Zhang zhaohui song Shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghai 200241China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710126China Space Information Research Institute Hangzhou Dianzi UniversityHangzhou310018China Peng Cheng Laboratory Shenzhen 518052China Communication Engineering Research Center Harbin Institute of TechnologyShenzhen 518055China

Free space optical(FSO)communication has recently aroused great interest in academia due to its unique features,such as large transmission band,high data rates,and strong anti-electromagnetic *** the aim of evaluating the performance of an FSO communication system and extending the line-of-sight transmission distance,we propose an unmanned aerial vehicle(UAV)-assisted dual-hop FSO communication system equipped with amplifyand-forward protocol at the relay ***,we consider impairments of atmospheric absorption,pointing errors,atmospheric turbulence,and link interruptions due to angle-of-arrival fluctuations in the relay *** Gamma-Gamma and Malaga distributions are used to model the influence of atmospheric turbulence on the source-to-UAV and UAVto-destination links,*** derive closedform expressions of the probability density function(PDF)and cumulative distribution function(CDF)for the proposed communication system,in terms of the Meijer-G *** on the precise PDF and CDF,analytical expressions for the outage probability,average bit error rate,and ergodic capacity are proposed with the aid of the extended generalized bivariate Fox’s H ***,we show that there is a match between the analytical results and numerical results,and we analyze the influence of the system and channel parameters on the performance.

关键词： amplify-and-forward protocol angle-ofarrival fluctuations FSO communication Malaga distribution UAV relay

High Isolation and Low Correlation Small Size Multi-Antenna for MIMO Mobile Terminals

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China Communications 2012年第5期9卷 100-107页

作者： song zhaohui Ding Zhiyong Harbin Inst Technol Sch Elect & Informat Technol Harbin 150001 Peoples R China

A new method of forming a four-port multi-antenna by a two-unit patch antenna array is proposed to design a high isolation low correlation stroll size multi-antenna. Dual polarization is real-ized by the method of feeding in two ports. Defec-ted Ground Structure （DGS） is used to eliminate the coupling between the two antenna units. The test results show that the isolation between two ports reaches around 20dB, and that the antenna correlation coefficients is less than 0. 5, which meets the requirements of future mobile communi-cation systems and provides a solution to multi-antenna of MIMO terminals.

关键词： MIMO mobile terminal antenna corre-lation diversity

Systematic review and Meta-analysis of 26 randomized controlled clinical trials of Compound Danshen Dripping Pill for non-proliferating diabetic retinopathy

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Chinese Herbal Medicines 2022年第1期14卷 142-153页

作者： Yu Wang Lei Hao Zhipeng Huo Yuanxue Liu Yujing Sun zhaohui song State Key Laboratory of Core Technology in Innovative Chinese Medicine Tasly AcademyTasly Holding Group Co.Ltd.Tianjin 300410China

Objective:Diabetic retinopathy(DR) is the retinal consequence of chronic progressive diabetic microvascular leakage and ***-proliferating diabetic retinopathy(NPDR) is the early stage of *** eventually occurs to some degree in all patients with diabetes *** recent years,many clinical trials have shown that Compound Danshen Dripping Pill(CDDP) may be associated with the improvement of NPDR *** aim of this study was to quantitatively summarize the association between CDDP and the therapeutic effects of ***:It was conducted that a systematic literature search of Pub Med,Web of Science,CNKI,VIP and Wanfang Data updated in June 2020 with the following search terms:"diabetic retinopathy° or"retinopathy° or "DR° or "NPDR°,in combination with "Compound Danshen Dripping Pill° or "Salvia miltiorrhiza° or "Danshen°.Risk ratio(RR) and weighted mean difference(WMD) with their 95% confidence interval(CI) was calculated between treatment and control *** sensitivity analyses were undertaken by removing each individual study when high heterogeneity *** analysis,Metaregression,and publication bias analysis were also *** strength of evidence was evaluated with the Grading of Recommendation,Assessment,Development,and Evaluation(GRADE) ***:Twenty-six RCTs involving 2047 subjects were included to conduct a Meta-analysis after screening the studies,extracting the data,and assessing the study *** Stata15.0 software was utilized for ***-analysis indicated that curative effects of treatment group with CDDP was significantly better than control [RR = 0.54,95% CI(0.40,0.73);moderate-quality evidence].In addition,the results showed that CDDP was significantly associated with improving retinal hemorrhages[WMD =-0.62,95% CI(-0.78,-0.46);low-quality evidence],the vision [WMD = 0.14,and 95% CI(0.09,0.19),low-quality evidence],fundus fluorescence angiography [RR = 0.37 and 95% CI(0.23,0.60);low-qualit

关键词： Compound Danshen Dripping Pill diabetic retinopathy Meta-analysis randomized controlled clinical trial systemic review

Modeling of multibody systems with redundant joints

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Theoretical & Applied Mechanics Letters 2012年第6期2卷 22-26页

作者： zhaohui Qi,a) and Huitao song b) Department of Engineering Mechanics Dalian University of Technology,Dalian 116023,China Department of Engineering Mechanics Dalian University of Technology Dalian 116023 China

This paper deals with the modeling of a multibody system in which some pairs of bodies are connected by more than one joints with the same kinematic *** such system,the redundant joints must be removed out artificially to ensure the solvable condition of the equations of motion being *** is believed but not obvious that the redundant joints have no effect on the system *** give a strict positive proof of this argument and present a method to avoid the ambiguity in the reaction forces of redundant joints through contact analysis of joints.

关键词： multibody systems redundant constraints joints contact analysis

Structures,properties,and applications of zwitterionic polymers

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ChemPhysMater 2022年第4期1卷 294-309页

作者： Keyu Qu Zhiang Yuan Yanyan Wang zhaohui song Xuyang Gong Yi Zhao Qiyu Mu Qinghong Zhan Wenlong Xu Linlin Wang School of Chemistry and Materials Science Ludong UniversityYantai 264025China State Key Laboratory of Long-Acting and Targeting Drug Delivery System Shandong Luye Pharmaceutical Co.Ltd.Yantai 264000China

Zwitterionic polymers have attracted research attention in recent years owing to their unique molecular *** the same repeat unit,positive and negative charges are simultaneously located on a pair of cationic and anionic groups;therefore,zwitterionic polymers have a large dipole moment and numerous charged ***-though the molecular chain of the zwitterionic polymer can be maintained in an electrically neutral state overall,the coexistence of the oppositely charged groups confers extremely high polarity and excellent hydrophilicity to the *** the same time,the electricality of the polymer can be further regulated by the environmental pH and salt ions,which greatly broadens the scope of applications in different *** review introduces various structures of zwitterionic polymers and analyzes the reasons why zwitterionic polymers exhibit pH responsive-ness,anti-polyelectrolyte effects,and superior electrical *** application fields are also summarized by generalizing the research status of zwitterionic polymers,including applications in antifouling coatings,drug delivery,wastewater treatment,and sensors,etc.

关键词： Zwitterionic polymer Structural characteristic Charged group Property Application

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NoC处理单元随机舍入的启发式应用映射

计算机辅助设计与图形学学报 2011年第7期23卷 1263-1269页

作者：宋朝晖马光胜宋大雷哈尔滨工程大学计算机科学与技术学院哈尔滨150001 黑龙江电力职工大学计算机网络中心哈尔滨150030 中国海洋大学工程学院青岛266001

在性能约束的前提下,为了降低能量消耗,针对一个集成了异构IP块以分层星型拓扑互连的片上网络(NoC),采用多电压电平操作,运用一种统一方法来解决应用映射问题,并用混合整数线性程序公式化问题,提出了基于随机舍入的NoC处理单元启发式高... 详细信息

在性能约束的前提下,为了降低能量消耗,针对一个集成了异构IP块以分层星型拓扑互连的片上网络(NoC),采用多电压电平操作,运用一种统一方法来解决应用映射问题,并用混合整数线性程序公式化问题,提出了基于随机舍入的NoC处理单元启发式高效应用映射——HAMU法.实验结果表明,HAMU法的效能明显优于其他启发式方法.

关键词：片上网络混合整数线性程序随机舍入启发式应用映射

普光主体南部区块海相地层安全优快钻井技术实践

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断块油气田 2024年第4期31卷 707-713页

作者：宋兆辉中石化石油工程技术研究院有限公司北京102206

针对普光主体南部区块海相地层裂缝发育、存在大段盐膏层、储层井漏风险高、钻井时效低等问题,文中通过引入科学优化钻井系统,建立区域地质模型和岩石可钻性剖面,研选高效钻头和提速工具,实时优化钻井参数;构建强封堵复合盐钻井液体系,... 详细信息

针对普光主体南部区块海相地层裂缝发育、存在大段盐膏层、储层井漏风险高、钻井时效低等问题,文中通过引入科学优化钻井系统,建立区域地质模型和岩石可钻性剖面,研选高效钻头和提速工具,实时优化钻井参数;构建强封堵复合盐钻井液体系,动态精准计算钻井液井下循环当量密度,优化钻井液防漏堵漏措施;采用封隔式分级注水泥新型固井工具,形成一整套安全优快钻井技术。该技术在P3021-5井现场应用中取得了良好效果:飞仙关组单趟钻机械钻速达15.22 m/h,创工区最高纪录;盐膏层全程保持稳定,并有效预防了低压储层井漏和卡钻风险;缩短完井周期5 d。

关键词：科学优化钻井系统优快钻井海相普光主体南部区块

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树莓状聚合物纳微米封堵剂的制备及性能评价

石油钻探技术 2024年第3期52卷 84-90页

作者：宋兆辉中石化石油工程技术研究院有限公司北京102206

为解决硬脆性泥页岩地层井壁失稳问题,国内外通过乳液聚合方法研发了纳微米封堵剂,但在应用过程中存在纳微米尺寸不易保持、钻井液易起泡等问题。为此,以苯乙烯、甲基丙烯酸甲酯作为聚合反应单体,二乙烯基苯作为聚合反应内交联剂,以淀... 详细信息

为解决硬脆性泥页岩地层井壁失稳问题,国内外通过乳液聚合方法研发了纳微米封堵剂,但在应用过程中存在纳微米尺寸不易保持、钻井液易起泡等问题。为此,以苯乙烯、甲基丙烯酸甲酯作为聚合反应单体,二乙烯基苯作为聚合反应内交联剂,以淀粉纳米粒子为乳液稳定剂,通过Pickering乳液聚合法制备了一种用于水基钻井液的树莓状纳微米封堵剂(即表面吸附淀粉纳米粒子的交联P(St-co-MMA)微球)。对树莓状纳微米封堵剂的粒子直径、形貌及结构特点进行了表征分析,并对其性能进行了室内评价试验,结果发现,树莓状纳微米封堵剂能显著降低聚合物氯化钾钻井液的API滤失量和渗透封堵仪(PPA)滤失量,可有效封堵地层纳微米级孔隙,解决了钻井液的起泡问题,且对钻井液流变性能影响较小,能够满足页岩油气钻井井壁稳定的需求。

关键词：泥页岩井壁稳定 Pickering乳液乳液聚合纳微米封堵剂淀粉封堵性能

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高性能水基钻井液处理剂研究进展及发展趋势

化学通报 2024年第7期87卷 831-837页

作者：宋兆辉中石化石油工程技术研究院有限公司北京102206

钻井液是石油钻井工程的“血液”,具有清洁井眼、保护钻具、稳定井壁和平衡地层压力等重要作用。本文综述了高性能水基钻井液处理剂的研究进展,主要包括抑制剂、润滑剂、包被剂和降滤失剂,包含了国内外的最新研究成果,也涉及国外油服公... 详细信息

钻井液是石油钻井工程的“血液”,具有清洁井眼、保护钻具、稳定井壁和平衡地层压力等重要作用。本文综述了高性能水基钻井液处理剂的研究进展,主要包括抑制剂、润滑剂、包被剂和降滤失剂,包含了国内外的最新研究成果,也涉及国外油服公司和化学品公司在工程现场已经规模应用的先进产品。最后在现有高性能水基钻井液处理剂研究及应用的基础上,对其发展趋势进行了展望。

关键词：水基钻井液抑制剂润滑剂包被剂降滤失剂