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Parameter influence on electron collection efficiency of a bare electrodynamic tether

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Science China(Information Sciences) 2018年第2期61卷 24-35页

作者： gangqiang li Zheng H.ZHU Department of Earth and Space Science and Engineering York University Department of Mechanical Engineering York University

This study develops a coupled multiphysics finite element method for the dynamic analysis of a bare flexible electrodynamic tether. Contrary to the existing methods, the new method discretizes and solves the orbital motion limited equation and the dynamic equation of an elastic flexible tether ***, the new method is verified via comparison with the existing methods in a straight tether ***, the number of tether elements, tether bending deformation, and two design parameters at the cathodic end affecting the electrical current are investigated. It is determined that the tether bending deformation and the two parameters i.e., the impedance ZT and ΦPWhave a significant impact on the electron collection efficiency of an electrodynamic tether system. The results indicate that the proposed method should be applied in the refined mission analysis.

关键词： multiphysics coupled finite element electrodynamic tether electron collection efficiency

libration and end body swing stabilization of a parallel partial space elevator system

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Chinese Journal of Aeronautics 2021年第3期34卷 187-199页

作者： Gefei SHI gangqiang li Zheng H.ZHU School of Aeronautics and Astronautics Sun Yat-Sen UniversityGuangzhou 510275China Department of Mechanical Engineering York UniversityTorontoOntario M3J 1P3Canada

This paper studies the libration and stabilization of a parallel partial space elevator system in circular orbits. The system is made up of two paralleled partial space elevators, each of which consists of one main satellite, one end body and a climber moving along the tether between *** libration characteristics of the elevator are studied through numerical analysis by a new dynamic model, and a novel control strategy is proposed to stabilize the swing of the end body by projecting the climber speeds only. Optimal control method is used to implement the new control strategy in the case where the climbers move in opposite direction. The simulation results validate the effectiveness of the proposed control strategy whose application will neither sacrifice the transport efficiency nor exacerbate libration significantly.

关键词： libration stabilization Nonlinear dynamics Optimal control Parallel partial space elevator Space tether

Improved Design of Architecture of the Battlefield Situation Comprehensive Display System

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武汉大学学报:自然科学英文版 2023年第4期28卷 309-316页

作者： liU Yu ZHANG lili li gangqiang Teaching and Research Department of Unit 91976 PLAGuangzhou 510430GuangdongChina

The traditional chimney software architecture design,which is based on the application object,scale and equipment,is difficult to meet the urgent need of multi-resolution,multi-viewpoint,two-dimensional and three-dimensional consistent battlefield situation comprehensive *** to the idea of ***'s general operational diagram,the architecture of the current battlefield situation integrated display system is upgraded and *** at the problems of information splitting and real-time undifferentiated access of multi-domain heterogeneous data,technical means such as spatial analysis and multi-source data integration are put forward,and the problems of fast loading and visualization of 3D models of the large battlefield space are solved by designing force clustering and motion trajectory smoothing *** method improves the service ability and the level of the battlefield situation comprehensive display system,and has a broad arrange of application.

关键词： common operational picture(COP) architecture of battlefield situation visualization computer model

Expression, characterization, and antimicrobial ability of T4 lysozyme from methylotrophic yeast Hansenula polymorpha A16

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Science China(life Sciences) 2011年第6期54卷 520-526页

作者： WANG Nan WANG YueJu li gangqiang SUN Ning liU DeHu Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Department of Natural Sciences Northeastern State UniversityBroken ArrowOklahoma 74014USA

Lysozyme is an enzyme that is essential for protection against bacterial *** this study,a T4 lysozyme gene was cloned into the yeast expression vector pPIC9K under the control of the Pichia pastoris glyceraldehyde-3-phosphate dehydrogenase promoter (pGAP).A Hansenula polymorpha-derived ribosomal DNA (rDNA)-targeting element was inserted into the expression vector and was critical for stable DNA integration into the *** *** T4 lysozyme was successfully expressed in the yeast *** A16;0.49 g L-1 secreted recombinant T4 lysozyme was obtained 72 h after incubation in culture broth that had an initial pH of *** T4 lysozyme showed lytic activity against the cell walls of the gram positive bacteria,Micrococcus lysodeikticus,and the gram negative bacteria Xanthomonas campestris *** and Xanthomonas oryzae *** zone of inhibition assay was used to evaluate antimicrobial *** spectrometry showed the N-terminal sequence of recombinant T4 lysozyme was identical to that of the native ***-PAGE indicated that the molecular mass of recombinant T4 lysozyme was 18.7 kD which corresponds to a monomer of the native ***-PAGE without 0.2 mol L-1 dithiothreitol treatment detected two bands (15 and 31 kD) suggesting that some recombinant T4 lysozyme formed interand intra-molecular disulfide bonds which resulted in loss of enzyme activity.

关键词： T4 lysozyme antimicrobial activity Hansenula polymorpha pGAP rDNA

南疆典型灌区春播前表层土壤含水率空间分布研究

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干旱地区农业研究 2024年第2期42卷 264-271,292页

作者：刘一凡吕廷波宋仁友张晓宇陈伏龙付鑫法李港强石河子大学水利建筑工程学院新疆石河子832000 现代节水灌溉兵团重点实验室新疆石河子832000

采用7种插值方法(反距离权重法、径向基函数法、全局多项式法、局部多项式法、普通克里金法、泛克里金法、经验贝叶斯克里金法)对小海子灌区(南疆典型灌区)土壤含水率进行空间分布特征评估。结果表明:(1)研究区表层土壤含水率介于4.99%~... 详细信息

采用7种插值方法(反距离权重法、径向基函数法、全局多项式法、局部多项式法、普通克里金法、泛克里金法、经验贝叶斯克里金法)对小海子灌区(南疆典型灌区)土壤含水率进行空间分布特征评估。结果表明:(1)研究区表层土壤含水率介于4.99%~24.99%,变异系数为27.6%,属于中等变异,且具有中等的空间自相关性,指数模型拟合变异函数的效果较好。(2)对于同时受结构性因素与随机性因素影响的小海子灌区,将确定性插值径向基函数法应用于土壤含水率插值的精度较高。(3)通过对灌区表层土壤含水率空间分布图的分析,发现小海子灌区春播前土壤含水率在空间上呈现出西南高、东北低的规律,且受地下水位及灌溉措施影响较大;表层土壤含水率大于15%的面积占总面积的64.9%,从整体上看,灌区西南部与中部的土壤含水率已达到播种要求,东北部地区达到“干播湿出”的播种要求,灌区可安排相应的春播活动。

关键词：土壤水分空间分布空间插值法精度评价南疆灌区

Community Detection in Blockchain Social Networks

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Journal of Communications and Information Networks 2021年第1期6卷 59-71页

作者： Sissi Xiaoxiao Wu Zixian Wu Shihui Chen gangqiang li Shengli Zhang College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060China Peng Cheng Laboratory Shenzhen 518060China

In this work,we consider community detection in blockchain *** specifically take the Bitcoin network and Ethereum network as two examples,where community detection serves in different *** the Bitcoin network,we modify the traditional community detection method and apply it to the transaction social network to cluster users with similar *** the Ethereum network,on the other hand,we define a bipartite social graph based on the smart contract transactions.A novel community detection algorithm which is designed for low-rank signals on graph can help find users’communities based on user-token *** on these results,two strategies are devised to deliver on-chain advertisements to those users in the same *** implement the proposed algorithms on real *** adopting the modified clustering algorithm,the community results in the Bitcoin network are basically consistent with the ground-truth of the betting site community which has been announced to the ***,we run the proposed strategy on real Ethereum data,visualize the results and implement an advertisement delivery on the Ropsten test net.

关键词： blockchain Bitcoin Ethereum community detection recommendation

A Communication Method of Distributed Tactical Training Simulation System Suitable for Remote Interconnection

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Wuhan University Journal of Natural Sciences 2021年第6期26卷 473-480页

作者： li gangqiang liU Yu ZHANG lili li Chunhong ZHANG Wei Teaching and Research Department of Unit 91976 PLAGuangzhou 510430GuangdongChina Operational Laboratory of Naval Command College PLANanjing 210016JiangsuChina

The traditional distributed tactical training simulation system is limited by the availability and bandwidth of military network transmission channel and does not have the feasibility of remote interconnection and spatial sub-regional *** this paper,a new communication method of distributed tactical training simulation system is proposed to solve the problem of strong business coupling between nodes and system availability under the condition of low *** operator of federated exchange,federated queue and their concepts and design requirements are firstly proposed,and the inverted tree,triangle,ring exchange topology and circular queue structure are further ***,the expected goal of high-speed interworking between nodes in the cluster and high reliable transmission between clusters is *** example also shows that this method can significantly improve the throughput of single switching node and federated node after using reliability confirmation mechanism.

关键词： interconnection distributed system simulation training federation message queue

游离双足趾腓侧皮瓣修复相邻双指指腹缺损7例

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中华显微外科杂志 2024年第1期47卷 39-43页

作者：陈鑫梅俊霞杨坤宋振磊张艳娟李刚强苑巧巧许诺周口淮海医院显微手足外科周口市手足外科临床医学研究中心河南周口466000

目的:探讨应用双足趾腓侧皮瓣修复相邻双指指腹缺损的临床效果。方法:自2020年8月至2023年1月,周口淮海医院显微手足外科采用双足趾腓侧皮瓣修复7例14指指腹缺损,男4例,女3例;年龄19~45岁,平均28岁。创面位于左手4例,右手3例;示、中... 详细信息

目的:探讨应用双足趾腓侧皮瓣修复相邻双指指腹缺损的临床效果。方法:自2020年8月至2023年1月,周口淮海医院显微手足外科采用双足趾腓侧皮瓣修复7例14指指腹缺损,男4例,女3例;年龄19~45岁,平均28岁。创面位于左手4例,右手3例;示、中指损伤3例,中、环指损伤2例,拇、示指损伤2例,软组织缺损面积为1.2 cm×1.5 cm~3.0 cm×2.5 cm,皮瓣切取面积为1.5 cm×1.8 cm~3.2 cm×2.8 cm。其中急诊修复1例,择期手术修复6例;皮瓣供区直接闭合,创缘缝合张力较大时于足底内侧切取中厚皮片移植。术后采用门诊复诊、微信联系定期随访,观察手指外形、感觉、功能恢复与皮瓣挛缩情况以及双足趾活动情况。结果:术后7例皮瓣均顺利成活,皮瓣供区甲级愈合。术后定期随访6个月~2年,平均9个月。皮瓣外形美观、感觉优良,TPD达3~6 mm,手指功能恢复满意。趾皮瓣供区均只遗留线形瘢痕,关节活动度及行走步态正常。按中华医学会手外科学会上肢部分功能评定试用标准评定:优5例,良2例。结论:应用双足趾腓侧游离皮瓣是同期修复相邻双指指腹缺损的理想方法,可以达到良好的重建效果。

关键词：趾腓侧皮瓣指腹软组织缺损显微外科技术

春灌定额对棉田水温盐分布及棉花苗期生长发育的影响

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新疆农业科学 2024年第6期61卷 1336-1344页

作者：付鑫法吕廷波王久龙李港强宋仁友刘一凡石河子大学水利建筑工程学院/现代节水灌溉兵团重点实验室新疆石河子832000

【目的】研究新疆南疆小海子灌区不同春灌定额对棉田水温盐和棉花苗期生长的影响,为小海子灌区棉花苗期的春灌定额提供科学依据。【方法】设置3个春灌水分处理(W_(1):1350 m^(3)/hm^(2)、W_(2):1800 m^(3)/hm^(2)、W_(3):2250 m^(3)/hm^... 详细信息

【目的】研究新疆南疆小海子灌区不同春灌定额对棉田水温盐和棉花苗期生长的影响,为小海子灌区棉花苗期的春灌定额提供科学依据。【方法】设置3个春灌水分处理(W_(1):1350 m^(3)/hm^(2)、W_(2):1800 m^(3)/hm^(2)、W_(3):2250 m^(3)/hm^(2)),分析不同春灌定额对棉田水温盐与棉花苗期生长发育的影响。【结果】0~60 cm土层平均土壤含水率W_(3)处理高于W_(1)和W_(2)处理,在其上部耕作层保水能力更好。W_(3)处理较W_(1)、W_(2)处理不同土壤深度地温低,膜下地温均高于2膜间裸行地温。W_(1)处理表层含盐量低于W_(2)和W_(3)处理,0~50 cm的盐分淋洗率分别为6.77%、22.22%和30.03%,春灌水量越大淋洗盐分的效果越好,50~100 cm土壤平均积盐率分别为-39.89%、-58.95%和-68.91%,随着灌水量的增加,盐分被水分带入深层增多。W_(1)处理棉花幼苗的株高、茎粗与叶面积最大,一定的水分亏缺有利于棉花幼苗的生长。【结论】不同春灌定额均有一定程度的洗盐增墒作用,表现为W_(3)>W_(2)>W_(1)处理。

关键词：春灌土壤水分土壤盐分土壤温度盐分淋洗棉田