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Effect of the Grain for Green Project on freshwater ecosystem services under drought stress

Journal of Mountain Science 2022年第4期19卷 974-986页

作者： han hui-qing YANG Jian-qiang LIU Yue ZhanG Ying-jia WANG Jun-wen College of Architecture and Urban Planning Guizhou Institute of TechnologyGuiyang 550003China College of Economics and Management Guizhou Institute of TechnologyGuiyang 550003China

The Grain for Green Project(GGP) is an important measure for the prevention of sloping farmland and the restoration of natural *** project has been critical to the restoration of ecological environments in western China. However,the effect of the GGP on freshwater ecosystem services under extreme climates remains unclear. Thus, taking the middle and upper reaches of the Wujiang River Basin in western China as an example, this study assessed the variation of three freshwater ecosystem services(e.g., water yield, soil retention and nutrient retention) impacted by the GGP under drought stress by employing the Integrated Valuation of Ecosystem Services and Tradeoffs(In VEST) model. In addition,the trade-off/synergistic relationship between three freshwater ecosystem services was analyzed based on the Pearson correlation coefficient. As revealed from the results, the effect of the GGP on the water yield and nutrient retention under drought stress was significantly higher than that on the soil *** the increase in the drought degree, the variation rate of the water yield and nutrient retention impacted by the GGP increased, whereas that of the soil retention decreased. The GGP in droughts of different seasons resulted in a significant heterogeneity in the changes of three freshwater ecosystem services. The correlation coefficients between the water yield and soil retention as well as that between the water yield and the nutrient retention increased, and the correlation coefficients declined between soil and nutrient retention under different drought degrees following the GGP. Unlike for the summer drought case, there were no significant changes in the correlation coefficients between three freshwater ecosystem services in spring, autumn and winter droughts. The results suggest that the amount of farmland converted to shrubland should be regulated to reduce the trade-off intensity between freshwater ecosystem services. In addition, food security and e

关键词： Grain for Green Project Freshwater ecosystem services Drought Spatial pattern Tradeoff and synergy

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优良紫花苜蓿品种骑士t在庆阳市的适应性研究

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饲料研究 2024年第5期47卷 117-121页

作者：张金霞窦晓利耿智广梁万鹏韩庆辉庆阳市农业科学研究院甘肃庆阳745000 甘肃省农业科学院畜草与绿色农业研究所甘肃兰州730070 北京佰青源畜牧业科技发展有限公司北京101500

试验旨在探讨紫花苜蓿骑士t在庆阳市的综合生产能力及适应性。试验采用随机区组试验方法,分析引进品种骑士t、当地主栽品种甘农5号和陇东紫花苜蓿的田间生产性状、生长势、鲜草产量、营养成分和饲用价值。结果表明,苜蓿不同品种生长曲... 详细信息

试验旨在探讨紫花苜蓿骑士t在庆阳市的综合生产能力及适应性。试验采用随机区组试验方法,分析引进品种骑士t、当地主栽品种甘农5号和陇东紫花苜蓿的田间生产性状、生长势、鲜草产量、营养成分和饲用价值。结果表明,苜蓿不同品种生长曲线一致,但同一品种不同时期生长速度不同;3个苜蓿品种种植当年(春播)产量低,但品质优、营养价值高,初花期粗蛋白(CP)含量20%以上,酸性洗涤纤维(ADF)含量在28%~30%之间,中性洗涤纤维(NDF)含量在35.0%~38.5%之间,相对饲用价值(RFV)在161~172之间。骑士t播种当年越冬率为100%,抗寒性好,翌年第一茬株高达105.24 cm,显著高于甘农5号和陇东紫花苜蓿(P<0.05);茎粗为3.46 mm,显著低于甘农5号(P<0.05);鲜草产量达1 235.06 kg/667 m2。甘农5号抗旱性好,越夏成活率为73.38%,分枝较多,鲜草产量明显高于陇东紫花苜蓿(P<0.05)。骑士t粗脂肪含量低,但RFV高,鲜干比为2.96,粗蛋白和磷含量可达22.6%和0.3%,ADF和NDF含量为28.8%和35.97%,RFV为172,相对饲草品质(RFQ)为170,总可消化养分(TDN)含量为60%。研究表明,骑士t适宜在庆阳市及气候相似的区域种植。

关键词：紫花苜蓿骑士t 生长特性庆阳市

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Tradeoffs and synergies between ecosystem services : A comparison of the karst and non-karst area

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Journal of Mountain Science 2020年第5期17卷 1221-1234页

作者： han hui-qing LIU Yue GAO Hong-juan ZhanG Ying-jia WANG Zhe CHEN Xiao-qiao College of Architecture and Urban Planning Guizhou Institute of TechnologyGuiyang 550003China School of Geography and Resources Guizhou Education UniversityGuiyang 550018China

Under the influence of various natural and human factors, the relationship between the ecosystem services provided for human beings by a karst ecosystem is becoming increasingly complex, profoundly limiting the effective and sustainable development of the social economy and ecosystem protection in karst areas. Taking Guizhou, China as an example, which includes both karst(including five different landforms) and non-karst area, the study explored and compared the tradeoff and synergy between ecosystem services in both terrain types. The results showed higher change rates of water yield and soil retention in karst areas than those in non-karst areas, with only small differences in the carbon storage and crop production change. The ecosystem service relationships in the karst area from 1995 to 2005 were consistent with the relationships in the non-karst area. However, differences were observed in most of these relationships from 2005 to 2015. The relationships between ecosystem services in different karst landforms from 1995 to 2005 remained the same, but there are differences found in the relationships of ecosystem services from 2005 to 2015. The trade-off and synergistic relationships between ecosystem services in the different landforms were closely related to the changes of climate and land use, particularly related to rainfall, rainfall erosivity, farmland, and forestland.

关键词： Ecosystem service Tradeoff and synergy Spatial pattern Karst area Guizhou

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Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 878-892页

作者： Honghai Wang qing-Long han the College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state *** the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay *** that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the *** this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first *** allowable regions of consensus protocol parameters are *** necessary and sufficient conditions for determining effective protocol parameters are *** designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent ***,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are ***,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.

关键词： Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay

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Learning topological defects formation with neural networks in a quantum phase transition

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Communications in Theoretical Physics 2024年第5期76卷 68-76页

作者： han-qing Shi Hai-qing Zhang Center for Gravitational Physics Department of Space ScienceBeihang UniversityBeijing 100191China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Neural networks possess formidable representational power,rendering them invaluable in solving complex quantum many-body *** they excel at analyzing static solutions,nonequilibrium processes,including critical dynamics during a quantum phase transition,pose a greater challenge for neural *** address this,we utilize neural networks and machine learning algorithms to investigate time evolutions,universal statistics,and correlations of topological defects in a one-dimensional transverse-field quantum Ising ***,our analysis involves computing the energy of the system during a quantum phase transition following a linear quench of the transverse magnetic field *** excitation energies satisfy a power-law relation to the quench rate,indicating a proportional relationship between the excitation energy and the kink ***,we establish a universal power-law relationship between the first three cumulants of the kink numbers and the quench rate,indicating a binomial distribution of the ***,the normalized kink-kink correlations are also investigated and it is found that the numerical values are consistent with the analytic formula.

关键词： neural networks machine learning transverse-field quantum Ising model kibble-zurek mechanism

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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第03期11卷 159-171页

作者： Rui Wen Shao Jun Wei Wu Zheng Xing Wang hui Xu han qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

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Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records

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Petroleum Science 2024年第2期21卷 1241-1256页

作者： hui-Wen Pang han-qing Wang Yi-Tian Xiao Yan Jin Yun-Hu Lu Yong-Dong Fan Zhen Nie National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China

Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network ***, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model.

关键词： Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records

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Escape probability for isotropic emitters near Kerr black hole with astrometric

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Communications in Theoretical Physics 2024年第5期76卷 128-133页

作者： Yu-Xuan han qing-Hua Zhu qing-Guo Huang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China School of Fundamental Physics and Mathematical Sciences hangzhou Institute for Advanced Study UCASHangzhou 310024China

The paper investigates the escape probability for isotropic emitters near a Kerr black *** propose a new approach to obtain the escape probability in a general manner,going beyond previous case-by-case *** approach is based on studies of the black hole shadow with astrometric observable and can be applied to emitters with an arbitrary 4-velocities and locations,even to the emitters outside of the equatorial *** also consider representative examples illustrating how escape probabilities vary with distance,velocity,and inclination ***,this new approach provides an effective method for studying escape probabilities near Kerr black holes.

关键词： Kerr black hole photon escape probability isotropic emitters

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Role of texture before rolling: a research based on texture and magnetic properties of 4.5 wt.% Si non-oriented electrical steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1973-1986页

作者： Yu-fan Wang Guo-qing Zu Shi-cheng Sun Ying han Wei-wei Zhu hui Wu Yu Zhao Xu Ran Key Laboratory of Advanced Structural Materials of Ministry of Education Changchun University of TechnologyChangchun 130012JilinChina CRRC Changchun Railway Vehicles Co. Ltd.Changchun 130000JilinChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia

The evolution of microstructure,texture,and magnetic properties with random texture,near-copper texture,weak near-cube texture,and strong λ fiber(/ND(normal direction))before rolling of non-oriented electrical steel was *** recrystallized hot bands with different textures but similar grain sizes were prepared by pre-annealing at low-temperature and high-temperature normalization *** was observed that the final annealed products exhibited similar recrystallized *** contrast,the final annealed product with more 2 fiber before rolling exhibited a stronger cube *** the fiber before rolling becoming stronger,the proportion of(111)deformed matrices became larger,which could be observed in the early recrystallization *** overwhelmingly dominant 2 orientation nuclei are formed in the(111)deformed matrix and become the dominant ***,the best magnetic properties are obtained in the products with strong 2 fiber before rolling,corresponding to the strong cube texture and low anisotropyparameter.

关键词： Texture before rolling Non-oriented electrical steel-Nucleation Grain growth Magnetic property

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Hyperbolic Tangent Function-Based Protocols for Global/Semi-Global Finite-Time Consensus of Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1381-1397页

作者： Zongyu Zuo Jingchuan Tang Ruiqi Ke qing-Long han Seventh Research Division Beihang University(BUAA)Beijing 100191China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia IEEE

This paper investigates the problem of global/semi-global finite-time consensus for integrator-type multi-agent *** hyperbolic tangent function-based protocols are pro-posed to achieve global and semi-global finite-time consensus for both single-integrator and double-integrator multi-agent systems with leaderless undirected and leader-following directed commu-nication *** new protocols not only provide an explicit upper-bound estimate for the settling time,but also have a user-prescribed bounded control *** addition,compared to some existing results based on the saturation function,the pro-posed approach considerably simplifies the protocol design and the stability *** examples and an application demonstrate the effectiveness of the proposed protocols.

关键词： Consensus protocol finite-time consensus hyper-bolic tangent function multi-agent systems.

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