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Hybrid ecophysiological growth model for deciduous Populus tomentosa plantation in northern China

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Forest Ecosystems 2025年第1期 112-120页

作者： Serajis Salekin Mark Bloomberg Benye Xi Jinqiang Liu Yang Liu Doudou Li Euan G.Mason Scion Research (New Zealand Forest Research Institute Ltd.) New Zealand School of Forestry University of Canterbury state key laboratory of Efficient Production of Forest Resources Beijing Forestry University key laboratory for Silviculture and Forest Ecosystem Research in Arid-and Semi-Arid Region of National Forestry and Grassland Administration Beijing Forestry University key laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry University Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College

Short rotation plantation forestry（SRF） is being widely adopted to increase wood production, in order to meet global demand for wood products. However, to ensure maximum gains from SRF, optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth. Hybrid ecophysiological models, such as potentially useable light sum equation（PULSE） models, are useful tools requiring minimal input data that meet the requirements of SRF. PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data. Therefore, it is prudent to question: can adding detailed soil and climatic data reduce errors in this type of model? In addition, PULSE techniques have not been used to model deciduous species, which are a challenge for ecophysiological models due to their phenology. This study developed a PULSE model for a clonal Populus tomentosa plantation in northern China using detailed edaphic and climatic data. The results showed high precision and low bias in height（m） and basal area(m2·ha-1) predictions. While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding, the study suggested that local climatic data could also be employed. The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias.

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The Marine Redox Change and Nitrogen Cycle in the Early Cryogenian Interglacial Time: Evidence from Nitrogen Isotopes and Mo Contents of the Basal Datangpo Formation, Northeastern Guizhou, South China

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Journal of Earth Science 2016年第2期27卷 233-241页

作者： Wei Wei Dan Wang Da Li Hongfei Ling Xi Chen Guangyi Wei Feifei Zhang Xiangkun Zhu Bin Yan state key laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Institute of Geology CAGS Laboratory of Isotope Geology MLR State Key Laboratory for Continental Tectonics and Dynamics

Cryogenian Datangpo Formation was deposited during the interglacial time between the Sturtian and Marinoan ice ages. We studied nitrogen isotope compositions and contents of Mo of the black shales from the basal Datangpo Formation in northeastern Guizhou, South China, for an attempt to reconstruct the marine redox change and nitrogen cycle during the interglacial time. Based on lithostratigraphy as well as geochemical profiles, the basal black shales can be divided into four intervals： Interval 1 has the lowest δ^（15）N value（＋5.0‰）; in interval 2, δ^（15）N values vary between ＋6.4‰ and ＋7.4‰（the first peak）; interval 3 records stable values of δ^（15）N around ＋6‰; and interval 4 is characterized by its higher δ^（15）N values, between ＋6.7‰ and ＋7.8‰（the second peak）. The values of enrichment factor of Mo decrease from 56.8 to 2.6 with the ascending stratigraphic trend. It indicated that immediately after the Sturtian glaciations, the marine seawater above the transitional zone between the shelf to slope of the southern margin of the Yangtze Platform was stratified, with shallow seawater being oxic but deep water being sulfidic. Subsequently, high denitrification rates prevailed in expanded suboxic areas in spite of a short emergence of an oxic condition in the surface seawater, and the deep seawaters were still anoxic or even euxinic.

关键词： nitrogen isotope molybdenum content Early Cryogenian interglacial time black shale,Datangpo Formation Yangtze Platform South China.

In-situ observations of damage-fracture evolution in surrounding rock upon unloading in 2400-m-deep tunnels

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International Journal of Mining Science and Technology 2023年第4期33卷 437-446页

作者： Haosen Guo Qiancheng Sun Guangliang Feng Shaojun Li Yaxun Xiao Jiangxi key laboratory of Disaster prevention-mitigation and Emergency Management Nanchang 330013China key laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of EducationYichang 443002China College of Civil Engineering and Architecture China Three Gorges UniversityYichang 443002China state key laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China

The damage-fracture evolution of deep rock mass has obvious particularity,which is revealed in 2400-mdeep tunnels by field *** evolution of the excavation damaged zone depth is consistent with that of the fractured zone *** ratio of the excavation damaged zone depth to the excavation fractured zone depth is greater than 2.0 in a rock mass with both high strength and good integrity,but less than1.5 in a rock mass with lower strength or poor *** disintegration in a rock mass with high strength and fair integrity is more likely to occur when it contains more than two groups of primary fractures in damaged *** develop outward in zonal disintegration but are totally different from the single-zone fracture,in which the fractures develop inward,and it is the starting position of the fractured zone when the excavation surface of the middle pilot is 7–9 m close to the pre-set borehole and it stops after the excavation surface of the baseplate is 11–14 m *** most intense evolution occurs around 2–4 m from the pre-set borehole in the sidewall expansion *** research results provide a reference for the monitoring scheme and support design of CJPL-Ⅲin its future construction.

关键词： Deep tunnel Fractured zone Damaged zone In-situ observation Unloading of rock mass

Multi-parameter Sensitivity Analysis and Application Research in the Robust Optimization Design for Complex Nonlinear System

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 55-62页

作者： MA Tao ZHANG Weigang ZHANG Yang TANG Ting state key laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University

The current research of complex nonlinear system robust optimization mainly focuses on the features of design parameters, such as probability density functions, boundary conditions, etc. After parameters study, high-dimensional curve or robust control design is used to find an accurate robust solution. However, there may exist complex interaction between parameters and practical engineering system. With the increase of the number of parameters, it is getting hard to determine high-dimensional curves and robust control methods, thus it＇s difficult to get the robust design solutions. In this paper, a method of global sensitivity analysis based on divided variables in groups is proposed. By making relevant variables in one group and keeping each other independent among sets of variables, global sensitivity analysis is conducted in grouped variables and the importance of parameters is evaluated by calculating the contribution value of each parameter to the total variance of system response. By ranking the importance of input parameters, relatively important parameters are chosen to conduct robust design analysis of the system. By applying this method to the robust optimization design of a real complex nonlinear system-a vehicle occupant restraint system with multi-parameter, good solution is gained and the response variance of the objective function is reduced to 0.01, which indicates that the robustness of the occupant restraint system is improved in a great degree and the method is effective and valuable for the robust design of complex nonlinear system. This research proposes a new method which can be used to obtain solutions for complex nonlinear system robust design.

关键词： complex nonlinear system global sensitivity analysis robust optimization design grouped variables

Sb_(2)WO_(6)/BiOBr 2D nanocomposite S-scheme photocatalyst for NO removal

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Journal of Materials Science & Technology 2020年第21期56卷 236-243页

作者： Yanyu Wang Kai Wang Jinlong Wang Xiaoyong Wu Gaoke Zhang Hubei key laboratory of Mineral Resources Processing and Environment State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhan430070China

Photocatalysis technology is an efficient method for removing nitrogen oxides at low ***,dimension-matched Sb_(2)WO_(6)/BiOBr photocatalysts were synthesized at room temperature via precipitation-deposition *** visible light irradiation,the as-obtained Sb_(2)WO_(6)/Bi OBr photocatalysts showed enhanced photocatalytic performance compare with the pure Sb_(2)WO_(6) and BiOBr for removal of *** optimal ratio for photocatalytic performance of Sb_(2)WO_(6)/BiOBr composite was found to be 30 wt.%of Sb_(2)WO_(6),which showed excellent recycling property even after 5 ***,in situ DRIFT was carried out to reveal the time-dependent evolution of reaction intermediates during photocatalytic NO *** probable photocatalytic mechanism was considered based on the active species capture *** enhanced photocatalytic performance for the Sb_(2)WO_(6)/BiOBr composite photocatalyst perhaps is attributed to the interaction between BiOBr and Sb2WO6 and S-scheme charge transfer path.

关键词： Sb_(2)WO_(6) BiOBr Photocatalytic NO removal S-scheme

Robust power allocation algorithm for analog network coding with imperfect CSI

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Science China(Information Sciences) 2014年第4期57卷 124-133页

作者： ZHANG ChenSi GE JianHua LI Jing HU Yun state key laboratory of Integrated Service Networks Xidian University

Power allocation promises significant benefits in wireless ***,these benefits depend on knowledge of the channel state information(CSI),which is hardly ***,robust algorithms that take into account such CSI uncertainties play an important role in the design of practical *** this paper,we formulate the power allocation problem as the maximum individual outage probability minimization subject to total power consumption for analog network coding(ANC)protocol of a two-way relay *** show that these problems can be cast as convex optimization ***-robust power allocation algorithm is first developed under the ideal assumption of perfect *** we introduce robust optimization methodology that accounts for the imperfect *** show that ignoring CSI uncertainties in our designs can lead to drastic performance *** the other hand,the proposed robust power allocation provides significant performance gain over non-robust power allocation and uniform power allocation in terms of overall system outage probability over a wide range of channel estimation *** work highlights the importance of the proposed robust algorithm in realistic two-way relaying networks.

关键词： analog network coding(ANC) outage probability two-way relay robust power allocation imperfect channel state information(CSI)

Development of Chinese large-scale space end-effector

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Journal of Central South University 2011年第3期18卷 600-609页

作者：刘宏谭益松刘伊威介党阳高凯蔡鹤皋 state key laboratory of Robotics and System Harbin Institute of Technology

In order to achieve large tolerance capture and high stiffness connection for space payload operations,a Chinese large-scale space end-effector (EER) was *** flexible steel cables were adopted to capture the payload with large capture *** screw transmission mechanism and plane shape-constraint four bar linkage mechanism were utilized to connect the payload with high *** experiments show that capture tolerances in X,Y,Z,Pitch,Yaw,Roll directions are 100 mm,100 mm,120 mm,10.5°,10.5°,12°,*** maximum connection stiffness is 4 800 N·*** end-effector could meet the requirements for space large tolerance capture and high stiffness connection in the future.

关键词： large tolerance capture high stiffness connection end-effector flexible steel cable ball screw four bar linkage

Contrary description logic: Gentzen deduction system

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Science China(Information Sciences) 2017年第11期60卷 171-179页

作者： Wei LI Yuefei SUI Jie LUO Bo CHEN state key laboratory of Software Development Environment Beihang University key laboratory of Intelligent Information Processing Institute of Computing TechnologyChinese Academy of Sciences

Traditional description logics are based on complementary rather than contrary concepts. This work proposes a contrary description logic based on the contrary concept constructors ～, ?(instead of ?).A Gentzen-type deduction system is applied to make the system sound and complete with the three-valued semantics of contrary description logic.

关键词： description logics contradictory contrary soundness completeness

A new class of ion-ion interaction: Z-bond

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Science China Chemistry 2015年第3期58卷 495-500页

作者： Kun Dong Suojiang Zhang Qian Wang state key laboratory of Multiphase Complex Systems Beijing key laboratory of Ionic Liquids Clean Process Institute Process Engineering Chinese Academy of Sciences

The hydrogen-bond interactions in ionic liquids have been simply described by the conventional hydrogen-bond model of A–H···B. Coupling with the strong electrostatic force, however, hydrogen bond between the cation and anion shows particular features in the geometric, energetic, electronic, and dynamic aspects, which is inherently different from that of the conventional hydrogen bond. A general model could be expressed as +[A–H···B]-, in which A and B represent heavy atoms and "+" and "–" represent the charges of the cation containing A atom and anion containing B atom, respectively. Because the structure shows a "zig-zag" motif, this coupling interaction is defined here as the Z-bond. The new model could be generally used to describe the interactions in ionic liquids, as well as bio-systems involved in ions, ionic reaction, and ionic materials.

关键词： ionic liquid interaction hydrogen bond Z-bond