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Stability analysis in an AVQ model of Internet congestion control algorithm

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 22-28页

作者： ZHAN Zhen-qiu zhu Jie XU Di Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China

This paper focuses on the local stability of a classical congestion control model in the Intemet, namely adaptive virtual queue （AVQ） algorithm with feedback delay. Firstly, necessary and sufficient stability conditions in terms of key tuning parameters are given, which can provide exact guidelines for setting system parameters. Furthermore, by computing the rightmost characteristic root, the optimal parameter configuration for AVQ is derived, which can guarantee superior stability performance. Finally, some simulation examples are given to illustrate the correctness of the theoretical analysis.

关键词： congestion control AVQ stability time delay system

Mass-producible low-cost flexible electronic fabrics for azo dye wastewater treatment by electrocoagulation

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Chinese Journal of Chemical Engineering 2023年第7期59卷 222-230页

作者： Chaoyi Yin Jingyuan Ma jian qiu Ruifang Liu Long Ba State Key Laboratory of Bioelectronics School of Biological Science and Medical Engineering Southeast UniversityNanjing 210096China State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneCollege of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Electrocoagulation is progressively becoming an ecologically friendly water treatment method owing to its lack of secondary pollution,high active ingredient concentration,high treatment effectiveness,simple equipment,and simplicity of automated control ***,electrocoagulation is offered as a method for treating wastewater containing azo dyes using a revolutionary flexible electronic fabric that can be mass-producible at a reasonable price.A computer-controlled machine embroiders 316L stainless steel fiber(316L SSF)onto an insulating fabric to manufacture a flexible electronic device of cathode and anode with a monopolar arrangement on the fabric *** methyl orange(MO)solution to simulate azo dye wastewater,the decolorization rate of 500 ml MO reached 99.25% under the conditions of 50 mg·L^(-1)initial mass concentration,120 min electrolysis time,15 mA·g^(-1)current density,1 cm electrode spacing,0.1 mol·L^(-1)NaCl,pH 7.6,200 r·min^(-1)rotational speed of the stirrer,and 22-25℃ room *** addition,it is feasible to embroider flexible electronic fabrics with varied sizes and numbers of electrodes based on the amount of treated sewage to increase the degradation rate,which has significant practical application value.

关键词： Flexible electronic fabric 316L Stainless steel fiber Embroidery Electrocoagulation Wastewater treatment

Comparison of three filters in asteroid-based autonomous navigation

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Research in Astronomy and Astrophysics 2014年第3期14卷 329-344页

作者： Wen Cui Kai-jian zhu State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control Center

At present, optical autonomous navigation has become a key technologyin deep space exploration programs. Recent studies focus on the problem of orbit de-termination using autonomous navigation, and the choice of filter is one of the mainissues. To prepare for a possible exploration mission to Mars, the primary emphasisof this paper is to evaluate the capability of three filters, the extended Kalman filter（EKF）, unscented Kalman filter （UKF） and weighted least-squares （WLS） algorithm,which have different initial states during the cruise phase. One initial state is assumedto have high accuracy with the support of ground tracking when autonomous navi-gation is operating; for the other state, errors are set to be large without this *** addition, the method of selecting asteroids that can be used for navigation fromknown lists of asteroids to form a sequence is also presented in this study. The simula-tion results show that WLS and UKF should be the first choice for optical autonomousnavigation during the cruise phase to Mars.

关键词： celestial mechanics asteroids equation of state methods: data analysis techniques: image processing

Coupled quantum molecular cavity optomechanics with surface plasmon enhancement

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Photonics Research 2017年第5期5卷 450-456页

作者： jian LIU KA-DI zhu Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education) School of Physics and Astronomy Shanghai Jiao Tong University

Cavity optomechanics is applied to study the coupling behavior of interacting molecules in surface plasmon systems driven by two-color laser beams. Different from the traditional force–distance measurement, due to a resonant frequency shift or a peak splitting on the probe spectrum, we have proposed a convenient method to measure the van der Waals force strength and interaction energy via nonlinear spectroscopy. The minimum force value can reach approximately 10^(-15) N, which is 3 to 4 orders of magnitude smaller than the widely applied atomic force microscope(AFM). It is also shown that two adjacent molecules with similar chemical structures and nearly equal vibrational frequencies can be easily distinguished by the splitting of the transparency peak. Based on this coupled optomechanical system, we also conceptually design a tunable optical switch by van der Waals interaction. Our results will provide new approaches for understanding the complex and dynamic interactions inmolecule–plasmon systems.

关键词： Coupled quantum molecular cavity optomechanics with surface plasmon enhancement THz

An Autophosphorylation Site of the Protein Kinase SOS2 Is Important for Salt Tolerance in Arabidopsis

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Molecular Plant 2009年第1期2卷 183-190页

作者： Hiroaki Fujii jian-Kang zhu Department of Botany and Plant Sciences 2150 Batchelor Hall University of California Riverside CA 92521 USA

The protein kinase SOS2 （Salt Overly Sensitive 2） is essential for salt-stress signaling and tolerance in Arabidopsis. SOS2 is known to be activated by calcium-SOS3 and by phosphorylation at its activation loop. SOS2 is autophosphorylated in vitro, but the autophosphorylation site and its role in salt tolerance are not known. In this study, we identified an autophosphorylation site in SOS2 and analyzed its role in the responses of Arabidopsis to salt stress. Mass spectrometry analysis showed that Ser 228 of SOS2 is autophosphorylated. When this site was mutated to Ala, the autophosphorylation rate of SOS2 decreased. The substrate phosphorylation by the mutated SOS2 was also less than that by the wild-type SOS2. In contrast, changing Ser228 to Asp to mimic the autophosphorylation enhanced substrate phosphorylation by SOS2. Complementation tests in a sos2 mutant showed that the S228A but not the $228D mutation partially disrupted the function of SOS2 in salt tolerance. We also show that activation loop phosphorylation at Thr168 and autophosphorylation at Ser228 cannot substitute for each other, suggesting that both are required for salt tolerance. Our results indicate that Ser 228 of SOS2 is autophosphorylated and that this autophosphorylation is important for SOS2 function under salt stress.

关键词： SOS2 autophosphorylation salt tolerance protein kinase Arabidopsis

An optimized sequential extraction scheme for molybdenum association in environmental samples

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Acta Geochimica 2016年第2期35卷 111-119页

作者： Liang Liang jian-Ming zhu State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 People's Republic of China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083China University of Chinese Academy of Sciences Beijing 100049People's Republic of China

By comparing three sequential extraction pro- cedures, a new optimized extraction scheme for the molyb- denum association in environmental samples was proposed. Five operational steps were described as exchangeable （KH2PO4 ＋ K2HPO4： including water-soluble）, associated with organic matter （NaOH）, Fe-Mn oxides and/or carbonates （HC1）, sulfides （H2O2） and residue （HNO3 ＋ HF ＋ H2O2）. An optimized extraction scheme was com- pared with Tessier＇s procedure and the Commission of European Communities Bureau of Reference （BCR） was applied to black shales. Results showed Tessier＇s procedure gave the lowest concentration values for exchangeable molybdenum and the highest values for the residual molybdenum, which could not present the efficiency of the extraction reagents. BCR＇s procedure showed the highest values in oxidizable molybdenum and presented four fractions of molybdenum, which did not demonstrate the fractions of molybdenum in the black shales in detail. The optimized extraction scheme demonstrated a certain improvement on extraction efficiency over Tessier＇s proce- dure for the lowest residual molybdenum, and revealed morefeatured fraction information of molybdenum in black shales than BCR＇ s. Therefore, after a comparison with other two extraction procedures, the optimized extraction scheme proved suitable for the molybdenum in black shales and it also showed an accurate determination of the molybdenum in the fractions and source of bioavailable Mo.

关键词： Molybdenum Sequential extractionprocedure Black shales

Micro RNAs and Short-interfering RNAs in Plants

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Journal of Integrative Plant Biology 2007年第6期49卷 817-826页

作者： Ramanjulu Sunkar jian-Kang zhu Department of Biochemistry and Molecular Biology Oklahoma State University Stillwater OK 74078 USA Department of Botany and Plant Sciences University of California Riverside CA 95251 USA

Gene silencing can occur either at the transcriptional level or post-transcriptional level or both. Many instances of sequence-specific silencing requires small RNAs that can be divided into two major classes： microRNAs （miRNAs） and short-interfering RNAs （siRNAs）. miRNAs function in post-transcriptional gene silencing by guiding mRNA degradation or translational repression, Endogenous siRNAs are more diverse in plants than in animals and can direct post-transcriptional gene silencing through mRNA degradation or transcriptional gene silencing by trigger- ing DNA methylation and histone modifications. This review discusses recent advances in the field of small RNA- guided gene silencing in plants including rice.

关键词： gene silencing microRNAs short-interfering RNAs plants.

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方钢管混凝土柱穿入式组合节点耗能机制

Profiles of Blow-up Solutions for the Gross-Pitaevskii Equation

工程力学 2025年第1期42卷 116-128页

作者：徐庆元雷建雄丁发兴周期石张华帅邱远光杨建军中南大学土木工程学院湖南长沙410075 中铁城建集团有限公司湖南长沙410075 中铁城建第一工程有限公司湖南长沙410075

开展了4个翼缘削弱的钢管混凝土柱穿入式组合节点抗震性能与三维实体有限元精细化模型分析。在混凝土三轴塑性损伤和钢材混合强化模型基础上，进一步引入钢材的韧性损伤模型，探讨了钢梁削弱程度对节点抗震性能与破坏形式的影响规律，... 详细信息

开展了4个翼缘削弱的钢管混凝土柱穿入式组合节点抗震性能与三维实体有限元精细化模型分析。在混凝土三轴塑性损伤和钢材混合强化模型基础上，进一步引入钢材的韧性损伤模型，探讨了钢梁削弱程度对节点抗震性能与破坏形式的影响规律，结果显示引入钢材韧性损伤的有限元模型分析结果与试验结果更加吻合，且钢梁削弱程度降低了该节点的刚度、承载力和耗能。随后对不同钢梁尺寸和柱端拉筋强构造下的组合节点进行了承载力、刚度和塑性耗能分配与失效机制的影响规律分析，分析结果表明：穿入式节点分别在梁-柱抗弯承载力比介于1.66~2.11、梁-柱线刚度比介于1.90~1.96、梁-柱截面刚度比介于1.16~1.21时，将由梁耗能向柱耗能转变;柱端拉筋强构造技术后，由于拉筋直接约束混凝土，大幅度提升了柱端抗弯承载力和耗能能力，组合节点在高轴压比时仍维持梁端失效破坏模式;根据《建筑抗震设计规范》，梁-柱抗弯承载力比取值小于1时为强柱弱梁，这对穿入式组合节点强柱弱梁的定义较为保守。

关键词：方钢管混凝土柱钢-混凝土组合梁穿入式组合节点韧性损伤塑性耗能

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Acta Mathematicae Applicatae Sinica 2010年第4期26卷 597-606页

作者： Shi-hui zhu jian Zhang College of Mathematics Sichuan UniversityChengdu 610064China College of Mathematics and Software Science Sichuan Normal UniversityChengdu 610066China

This paper is concerned with the blow-up solutions of the Cauchy problem for Gross-Pitaevskii *** terms of Merle and Raphёel＇s arguments as well as Carles＇ transformation,the limiting profiles of blow-up solutions are *** addition,the nonexistence of a strong limit at the blow-up time and the existence of L2 profile outside the blow-up point for the blow-up solutions are obtained.

关键词： Gross-Pitaevskii equation blow-up solution Bose-Einstein condensate limiting profile harmonic potential