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science china mathematics 2010年第1期53卷 105-114页

作者： fu baohua institute of mathematics, academy of mathematic and systems science, chinese academy of sciences, beijing 100190, china institute of mathematics Academy of Mathematic and Systems Science Chinese Academy of Sciences Beijing China

We propose two conjectures of Hard Lefschetz type on Chow groups and prove them for some special cases. For abelian varieties, we show that they are equivalent to the well-known conjectures of Beauville and Murre.

关键词： Chow groups abelian varieties Bloch-Beilinson conjectures Beauville conjecture Murre conjecture

IDENTIFICATION OF BOTH CLOSED-AND OPEN-LOOP STOCHASTIC SYSTEM WHILE STABILIZING IT

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Journal of systems science & Complexity 2002年第1期15卷 1-17页

作者： CHEN Hanfu(Han-fu Chen) (Laboratory of systems and Control,institute of systems science, academy of mathematics and systems science,chinese academy of sciences, beijing 100080, china) institute of systems science Academy of Mathematics and Systems Science Chinese Academy of Sciences Laboratory of Systems and Control CAS 北京 100080

This paper proposes a recursive algorithm estimating coefficients of the linear stochastic control system(ARX system) driven by a martingale difference sequence, while adaptively stabilizing the system without introducing external excitation signal. The system is allowed to be unstable and of nonminimum-phase. The estimates derived for the coefficients of both closed-loop and open-loop systems are strongly consistent.

关键词： System identification ARX system unstable nonminimum-phase strong consistency.

Designing regional pattern for ecosystem restoration:A case study

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science china(Technological sciences) 2006年第Z1期49卷 86-97页

作者： LI Guoqiang , MA Keming, fu Bojie & LIU Shiling State Key Lab of systems Ecology, Research Center for Eco-environmental sciences, chinese academy of sciences, beijing 100085, china Department of Water Environment, china institute of Water Resources and Hydropower Research, beijing 100038, china School of Environmental sciences, beijing Normal University, beijing 100875, china State Key Lab of systems Ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing China Department of Water Environment China Institute of Water Resources and Hydropower Research Beijing China School of Environmental sciences Beijing Normal University Beijing China

Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW china. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. (3) Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4) Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.

关键词： environmental factors, GIS, restoration species, Upper Minjiang River Valley.

Genetic analysis and candidate gene identification of salt tolerancerelated traits in maize

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Journal of Integrative Agriculture 2024年第7期23卷 2196-2210页

作者： Hui Fang Xiuyi fu Hanqiu Ge Mengxue Jia Jie Ji Yizhou Zhao Zijian Qu Ziqian Cui Aixia Zhang Yuandong Wang Ping Li baohua Wang Scientific Observing and Experimental Station of Maize in Plain Area of Southern Region Ministry of Agriculture and Rural Affairs/School of Life SciencesNantong UniversityNantong 226019China Maize Research institute Beijing Academy of Agriculture and Forestry Sciences(BAAFS)Beijing 100097China

Soil salinization poses a threat to maize production worldwide,but the genetic mechanism of salt tolerance in maize is not well ***,identifying the genetic components underlying salt tolerance in maize is of great *** the current study,a teosinte-maize BC2F7 population was used to investigate the genetic basis of 21 salt tolerance-related *** total,125 QTLs were detected using a high-density genetic bin map,with one to five QTLs explaining 6.05–32.02%of the phenotypic variation for each *** total phenotypic variation explained(PVE)by all detected QTLs ranged from 6.84 to 63.88%for each *** all 125 QTLs,only three were major QTLs distributed in two genomic regions on chromosome 6,which were involved in three salt tolerance-related *** addition,10 pairs of epistatic QTLs with additive effects were detected for eight traits,explaining 0.9 to 4.44%of the phenotypic ***,18 QTL hotspots affecting 3–7 traits were *** one hotspot(L5),a gene cluster consisting of four genes(ZmNSA1,SAG6,ZmCLCg,and ZmHKT1;2)was found,suggesting the involvement of multiple pleiotropic ***,two important candidate genes,Zm00001d002090 and Zm00001d002391,were found to be associated with salt tolerance-related traits by a combination of linkage and marker-trait association ***00001d002090 encodes a calcium-dependent lipid-binding(CaLB domain)family protein,which may function as a Ca^(2+)sensor for transmitting the salt stress signal downstream,while Zm00001d002391 encodes a ubiquitin-specific protease belonging to the C19-related *** findings provide valuable insights into the genetic basis of salt tolerance-related traits in maize and a theoretical foundation for breeders to develop enhanced salt-tolerant maize varieties.

关键词： maize salt tolerance-related traits QTL mapping region-based association analysis

FLOW-PIPE-SEEPAGE COUPLING ANALYSIS OF SPANNING INITIATION OF A PARTIALLY-EMBEDDED PIPELINE

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Journal of Hydrodynamics 2010年第4期22卷 478-487页

作者： GAO fu-ping LUO Cheng-cai Key Laboratory for Hydrodynamics and Ocean Engineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China Centre for Offshore Foundation systems The University of Western Australia Nedlands WA 6907 Australia

The initiation of pipeline spanning involves the coupling between the flow over the pipeline and the seepage-flow in the soil underneath the *** pipeline spanning initiation is experimentally observed and discussed in this *** is qualitatively indicated that the pressure-drop induced soil seepage failure is the predominant cause for pipeline spanning initiation.A flow-pipe-seepage sequential coupling Finite Element Method（FEM） model is proposed to simulate the coupling between the water flow-field and the soil seepage-field.A critical hydraulic gradient is obtained for oblique seepage failure of the sand in the direction tangent to the *** study is performed to investigate the effects of inflow velocity,pipe embedment on the pressure-drop,and the effects of soil internal friction angle and pipe embedment-to-diameter ratio on the critical flow velocity for pipeline spanning *** is indicated that the dimensionless critical flow velocity changes approximately linearly with the soil internal friction angle for the submarine pipeline partially-embedded in a sandy seabed.

关键词： submarine pipeline pipeline spanning seepage failure flow-pipe-seepage coupling

Enhancing Green Ammonia Electrosynthesis Through Tuning Sn Vacancies in Sn‑Based MXene/ MAX Hybrids

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Nano-Micro Letters 2024年第5期16卷 154-168页

作者： Xinyu Dai Zhen‑Yi Du Ying Sun Ping Chen Xiaoguang Duan Junjun Zhang Hui Li Yang fu baohua Jia Lei Zhang Wenhui Fang Jieshan Qiu Tianyi Ma Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials of Liaoning Province College of ChemistryInstitute of Clean Energy ChemistryLiaoning UniversityShenyang 110036People’s Republic of China State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024People’s Republic of China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601People’s Republic of China School of Chemical Engineering The University of AdelaideAdelaideSA 5005Australia State Key Laboratory of High‑Efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021NingxiaPeople’s Republic of China School of science RMIT UniversityMelbourneVIC 3000Australia Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China College of Chemical Engineering State Key Laboratory of Chemical Resource EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia ***,relevant out-lab research is still in its ***,a novel Sn-based MXene/MAX hybrid with abundant Sn vacancies,Sn@Ti_(2)CTX/Ti_(2)SnC–V,was synthesized by controlled etching Sn@Ti_(2)SnC MAX phase and demonstrated as an efficient electrocatalyst for electrocatalytic N2 *** to the synergistic effect of MXene/MAX heterostructure,the existence of Sn vacancies and the highly dispersed Sn active sites,the obtained Sn@Ti2CTX/Ti_(2)SnC–V exhibits an optimal NH_(3) yield of 28.4μg h^(−1) mg_(cat)^(−1) with an excellent FE of 15.57% at−0.4 V versus reversible hydrogen electrode in 0.1 M Na_(2)SO_(4),as well as an ultra-long ***,this catalyst represents a satisfactory NH3 yield rate of 10.53μg h^(−1) mg^(−1) in the home-made simulation device,where commercial electrochemical photovoltaic cell was employed as power source,air and ultrapure water as feed *** as-proposed strategy represents great potential toward ammonia production in terms of financial cost according to the systematic technical economic *** work is of significance for large-scale green ammonia production.

关键词： Green ammonia synthesis N2 electroreduction Renewable energy Sn MXene/MAX hybrid

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2 Graduate University of the chinese academy of sciences, beijing 100049, china 3 College of Resources and Environmental science, Nanjing Agricultural University, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of the chinese academy of sciences Beijing China College of Resources and Environmental science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Output tracking by ILC for stochastic systems

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Output tracking by ILC for stochastic systems

第二十一届中国控制会议

作者： CHEN Han-fu (institute of systems science academy of mathematics and systems science, chinese academy of sciences, beijing 100080)

＜正＞The paper proposes an iterative learning control （ILC） algorithm for a linear stochastic system presented in state space form to track a desired realizable trajectory. The control generated by the algorithm converges to the optimal one a. s. under the condition that the product input-output coupling matrices is full-column rank in addition to some assumptions on noises. No other knowledge about system matrices and covariance matrices is required.

关键词： iterative learning control stochastic system a. s. convergence tracking stochastic approximation

来源： cnki会议评论

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综合集成系统重构及宏观经济研究中的应用

系统工程学报 2001年第5期16卷 349-353页

作者：舒光复中国科学院数学与系统科学研究院系统科学研究所北京100080

在介绍了从定性到定量综合集成的特点以后介绍了其实现的方法之一———综合集成系统重构分析 .然后提出了用系统重构灵敏度分析处理专家意见不一致的情况 ,它可与专家对有关方面的熟悉程度、经验的可信度相结合进行研讨与综合。

关键词：综合集成系统重构宏观经济决策支持系统

Stochastic Approximation with Non-Additive Measurement Noise

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Stochastic Approximation with Non-Additive Measurement Noise