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Nitrogen addition promotes soil carbon accumulation globally

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Sc.ence china Life Sc.ences 2025年第1期68卷 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang guoping c.en Jiangling Zhu c.engjun Ji Biao Zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest china School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and environmental change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(c) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global c cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOc) storage, but its effect on SOc components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOc and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOc(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOc components, N addition promoted the accumulation of plant-derived c(9.7%–28.5%) over microbial-derived c(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile c. consistently, N addition led to a greater increase in particulate organic c(11.9%) than mineral-associated organic c(3.6%), suggesting that N addition promotes c accumulation across all pools, with more increase in unstable than stable pools. The responses of SOc and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated c and a subsequent decrease in the overall stability of soil c pool, which underscores the importance of considering the effects of N enrichment on SOc components for a better understanding of c dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability

Active control and experiment study of a flexible hub-beam system

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Acta Mechanica Sinica 2010年第2期26卷 289-298页

作者： guoping cai Youyou Teng c. W. Lira Department of engineering Mechanics State Key Laboratory of Ocean Engineering Shanghai Jiaotong University 200240 Shanghai China Department of Building and construction City Universityof Hong Kong Tat Chee Avenue Kowloon Hong Kong China

The first-order approximation coupling （FOAc） model was proposed recently for dynamics and control of flexible hub-beam systems. This model may deal with system dynamics for both low and high rotation speed, while the classical zeroth-order approximation coupling （ZOAc） model is only available for low rotation speed. This paper assumes the FOAc model to present experimental study of active positioning control of a flexible hub-beam system. Linearization and nonlinear control strategies are both considered. An experiment system based on a DSP TMS320F2812 board is introduced. The difference between linearization and nonlinear control strategies are studied both numerically and experimentally. Simulation and experimental results indicate that, linearized controller can make the system reach an expected position with suppressed vibration of flexible beam, but the time taken to position is longer than expected, whereas nonlinear controller works well with precise positioning, suppression of vibration and time control.

关键词： Flexible hub-beam system First-order approximation coupling (FOAc) model Linearizationcontrol Nonlinear control Experiment

H型试剂对于大直径泥水盾构泥水分离处理的影响与应用

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岩土工程学报 2025年第1期47卷 153-163页

作者：张箭任国平尹义豪钟小春张春雷梁禹河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 中铁十四局集团大盾构工程有限公司江苏南京211800 河海大学环境学院江苏南京210098 中山大学土木工程学院广东珠海519082

针对广东湛江湾海底隧道施工中出现的盾构废弃泥浆脱水速率慢、泥渣含水率高与废浆排放污染等问题,研发了一种新型H型脱水试剂。通过絮凝脱水试验、微观机理试验以及现场生产试验,揭示了泥浆泥水分离体积比/上清液浊度/粒径分布和Zeta... 详细信息

针对广东湛江湾海底隧道施工中出现的盾构废弃泥浆脱水速率慢、泥渣含水率高与废浆排放污染等问题,研发了一种新型H型脱水试剂。通过絮凝脱水试验、微观机理试验以及现场生产试验,揭示了泥浆泥水分离体积比/上清液浊度/粒径分布和Zeta电位等变化规律,综合评价H型试剂与3种聚丙烯酰胺(PAM)在泥浆脱水效果方面的差异。结果表明:H型试剂与泥浆作用的最优添加量为0.5%;与PAM相比,H型试剂前期沉降速度较慢,但脱水后的泥渣含水率降低了约18.1%,且上清液非常清澈,7.8的pH值符合直接外排条件;H型试剂兼具了较好的桥网作用与电中和作用,使粒径ca排水通道,降低泥浆的黏滞性,提高泥浆压滤脱水的效率;与原脱水试剂相比,现场使用0.1%的H型试剂,可提高30.5%的脱水泥样含固率,降低20%的工程成本。

关键词：泥水盾构泥水分离絮凝脱水机理研究现场试验

Predictive Tracking control of Network-Based Agents With communication Delays

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IEEE/cAA Journal of Automatica Sinica 2018年第6期5卷 1150-1156页

作者： Tianyong Zhang guoping Liu School of Automation Harbin University of Science and TechnologyHarbin 150080 cTGT center School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of engineering University of South Wales PontypriddCF37 1DLUK

This paper investigates the remote tracking control problem of Network-based Agents with communication delays existing in both forward and feedback communication channels.A networked predictive tracking controller is proposed to compensate the negative effects caused by bilateral time-delays in a wireless network. Furthermore, the problem of consecutive data loss in the feedback channel is solved using aforementioned controller, where lateral movement perturbations are *** and experiments are provided for several cases,which verify the realizability and effectiveness of the proposed controller.

关键词： consecutive data loss network-based agents networked predictive control remote tracking time-delay

Robust fault-tolerant control for wing flutter under actuator failure

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chinese Journal of Aeronautics 2016年第4期29卷 1007-1017页

作者： Gao Mingzhou cai guoping Department of engineering Mechanics State Key Laboratory of Ocean Engineering Shanghai Jiaotong University

Many control laws, such as optimal controller and classical controller, have seen their applications to suppressing the aeroelastic vibrations of the aeroelastic system. However, those control laws may not work effectively if the aeroelastic system involves actuator faults. In the current study for wing flutter of reentry vehicle, the effect of actuator faults on wing flutter system is rarely considered and few of the fault-tolerant control problems are taken into account. In this paper, we use the radial basis function neural network and the finite-time H-infinity adaptive fault-tolerant control technique to deal with the flutter problem of wings, which is affected by actuator faults, actuator saturation, parameter uncertainties and external disturbances. The theory of this article includes the modeling of wing flutter and fault-tolerant controller design. The stability of the finite-time adaptive fault-tolerant controller is theoretically proved. Simulation results indicate that the designed fault-tolerant flutter controller can effectively deal with the faults in the flutter system and can promptly suppress the wing flutter as well. (c) 2016 chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd. This is an open access article under the cc BY-Nc-ND license.

关键词： Actuator fault Actuator saturation Aeroservoelasticity Fault-tolerant control Flutter Observer

片状铝粉与SiO_(2)气凝胶对硅溶胶/苯丙乳液双层涂料隔热性能的影响

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涂料工业 2025年第1期55卷 58-63页

作者：刘传龙刘荣鑫王莉杜国平山东兖州建设总公司山东济宁272100 南昌大学物理与材料学院南昌330031 丹东市第二中学辽宁丹东118000

为提高涂料保温隔热性能,以硅溶胶为主要成膜物,苯丙乳液为辅助成膜物,在基体表面形成双层隔热涂层,其中底层和顶层涂料分别以SiO_(2)气凝胶、片状铝粉作为隔热填料。系统研究了片状铝粉和SiO_(2)气凝胶对双层涂料隔热性能的影响,并对... 详细信息

为提高涂料保温隔热性能,以硅溶胶为主要成膜物,苯丙乳液为辅助成膜物,在基体表面形成双层隔热涂层,其中底层和顶层涂料分别以SiO_(2)气凝胶、片状铝粉作为隔热填料。系统研究了片状铝粉和SiO_(2)气凝胶对双层涂料隔热性能的影响,并对相关隔热机理进行了探讨。结果表明:片状铝粉含量为4%时涂层的隔热效果最好,与空白板相比隔热温差达到9.1℃;SiO_(2)气凝胶的添加量为4%~5%时,涂层的隔热性能最佳。片状铝粉的添加可使涂料具有反射型隔热性能,而SiO_(2)气凝胶的添加使涂料具有阻隔型隔热特性。结合这两者的隔热特性,成功构建了具有双机制隔热特性的双层涂料结构,其隔热温差达到了10.9℃,高于单一涂层的隔热效果。

关键词：硅溶胶双层涂料片状铝粉 SiO_(2)气凝胶隔热保温

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cycle-slip Detection of GPS carrier Phase with Methodology of SA4 Multi-wavelet Transform

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chinese Journal of Aeronautics 2012年第2期25卷 227-235页

作者： HUO guoping MIAO Lingjuan School of Automation Beijing Institute of Technology Beijing 100081 China Key Laboratory of Intelligent control and Decision of complex Systems Beijing 100081 China

That cycle-slips remain undetected will significantly degrade the accuracy of the navigation solution when using carrier phase measurements in global positioning system （GPS）. In this paper, an algorithm based on length-4 symmetric/anti-symmetric （SA4） orthogonal multi-wavelet is presented to detect and identify cycle-slips in the context of the feature of the GPS zero-differential carrier phase measurements. Associated with the local singularity detection principle, cycle-slips can be detected and located precisely through the modulus maxima of the coeffic.ents achieved by the multi-wavelet transform. Firstly, studies are focused on the feasibility of the algorithm employing the orthogonal multi-wavelet system such as Geronimo-Hardin-Massopust （GHM）, chui-Lian （cL） and SA4. Moreover, the mathematical characterization of singularities with Lipschitz exponents is explained, the modulus maxima from wavelet to multi-wavelet domain is extended and a localization formula is provided from the modulus maxima of the coeffic.ents to the original observation. Finally, field experiments with real receiver are presented to demonstrate the effectiveness of the proposed algorithm. Because SA4 possesses the specific nature of good multi-filter properties （GMPs）, it is superior to scalar wavelet and other orthogonal multi-wavelet candidates distinctly, and for the half-cycle slip, it also remains better detection, location ability and the equal complexity of wavelet transform.

关键词： satellite navigation cycle-slip detection orthogonal multi-wavelet good multi-filter properties singularity detection

Analysis of the Mechanism Underlying Tibetan Plateau Vortex Frequency Difference between Strong and Weak MJO Periods

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Journal of Meteorological Research 2017年第3期31卷 530-539页

作者： guoping LI Fuhu ZHAO School of Atmospheric Sc.ences Chengdu University of Information Technology collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology chongqing Meteorological Observatory

In this paper, the NcEP/DOE reanalysis data, OLR data from NOAA, Australian Meteorological Bureau real-time multivariate MJO index, and Tibetan Plateau vortex （TPV） statistical data from the c.engdu Institute of Plateau Met- eorology, are used to discuss the modulation of the TPV by the MJO, through applying the wavelet analysis and com- posite analysis. The results show that：（1） The MJO plays an important role in modulating the TPV, as the number of TPVs generated in strong MJO periods is three times that in weak periods. （2） During strong （weak） MJO periods, the Tibetan Plateau （TP） is in control of a low-frequency, low-pressure cyclone （high-pressure, anticyclone） system, and thus the atmospheric circulation conditions over the plateau are conducive （inconducive） to the generation of TPVs. （3） During strong （weak） MJO periods, southerly （northerly） winds prevail in the east of the TP, while north- erly （southerly） winds in the west. Over the northern part of the TP, easterly （westerly） flow is predominant, while westerly （easterly） flow prevails over the south, thus conducive （inconducive） to the formation of cyclonic circula- tion （i.e., TPVs） at low altitude over the TP. （4） In strong MJO periods, water vapor is relatively less abundant over most of the TP, inconducive to the generation of TPVs; however, moisture transported by the south branch trough and the low-frequency, high-pressure anticyclone system from the Bay of Bengal, are very important for the develop- ment of TPVs. As the strength of the MJO changes continuously during its eastward propagation, the inten- sity of tropical convection and vertical circulation structures of the tropical atmosphere also change accordingly. Al- ternation between favorable and unfavorable conditions for the generation of TPVs occurs, thus resulting in signifi- cant frequency differences of TPVs between strong and weak MJO periods.

关键词： Tibetan Plateau vortex MJO modulation real-time multivariate MJO index composite analysis

Review of dynamics and active control of large-scale space membrane antenna

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Astrodynamics 2024年第1期8卷 1-26页

作者： Xiang Liu guoping cai Department of engineering Mechanics MOE Key Laboratory of HydrodynamicsChongqing Research InstituteShanghai Jiao Tong UniversityShanghai200240China

Large-scale space membrane antennas have significant potential in satellite communication,space-based early warning,and Earth *** of their large size and high flexibility,the dynamic analysis and control of membrane antenna are *** maintain the working performance of the antenna,the pointing and surface accuracies must be strictly ***,the accurate dynamic modeling and effective active control of large-scale space membrane antennas have great theoretical significance and practical value,and have attracted considerable interest in recent *** paper reviews the dynamics and active control of large-scale space membrane ***,the development and status of large-scale space membrane antennas are ***,the key problems in the dynamics and active control of large membrane antennas,including the dynamics of wrinkled membranes,large-amplitude nonlinear vibration,nonlinear model reduction,rigid-flexible-thermal coupling dynamic modeling,on-orbit modal parameter identification,active vibration control,and wave-based vibration control,are discussed in ***,the research outlook and future trends are presented.

关键词： large-scale space membrane antenna dynamicmodeling active control