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Journal of Magnesium and Alloys 2024年第1期12卷 251-266页

作者： fei-er shangguan Wei-li Cheng Yu-hang Chen Ze-qin Cui Hui Yu Hong-xia Wang Li-fei Wang Hang Li Hua Hou School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are *** grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing *** that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing *** electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical *** In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca *** micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly *** In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery.

关键词： Mg-air batteries Mg-Bi-Sn based alloys Electrochemical behaviors Discharge properties

Motion trajectory prediction based on a CNN-LSTM sequential model

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Science China(Information Sciences) 2020年第11期63卷 248-268页

作者： Guo XIE Anqi shangguan Rong fei Wenjiang JI Weigang MA Xinhong HEI School of Automation and Information Engineering School of Computer Science and EngineeringXi'an University of Technology

Accurate monitoring the surrounding environment is an important research direction in the field of unmanned systems such as bio-robotics, and has attracted much research attention in recent years. The trajectories of surrounding vehicles should be predicted accurately in space and time to realize active defense and running safety of an unmanned system. However, there is uncertainty and uncontrollability in the process of trajectory prediction of surrounding obstacles. In this study, we propose a trajectory prediction method based on a sequential model, that fuses two neural networks of a convolutional neural network(CNN) and a long short-term memory network(LSTM). First, a box plot is used to detect and eliminate abnormal values of vehicle trajectories, and valid trajectory data are obtained. Second, the trajectories of surrounding vehicles are predicted by merging the characteristics of CNN space expansion and LSTM time expansion;the hyper-parameters of the model are optimized according to a grid search algorithm, which satisfies the double-precision prediction requirement in space and time. Finally, data from next generation simulation(NGSIM) and Creteil roundabout in France are taken as test cases; the correctness and rationality of the method are verified by prediction error indicators. Experimental results demonstrate that the proposed CNNLSTM method is more accurate and features a shorter time cost, which meets the prediction requirements and provides an effective method for the safe operation of unmanned systems.

关键词： bio-robots unmanned system outlier detection hyper-parameters trajectory prediction

Formation mechanisms and remediation techniques for low-efficiency artificial shelter forests on the Chinese Loess Plateau

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Journal of Arid Land 2022年第8期14卷 837-848页

作者： WANG Yaobin shangguan Zhouping State Key Laboratory of Soil erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China

The construction of artificial shelter forests(ASFs)has resulted in substantial ecological,economic,and societal benefits to the Chinese Loess Plateau(CLP).However,the health and benefits of ASFs are being increasingly threatened by the formation of low-efficiency artificial shelter forests(LEASFs).In this study,LEASFs are systematically analyzed in terms of their status,formation mechanisms,and developmental *** key restoration techniques and schemes were summarized to improve the quality and efficiency of *** are formed by relatively complex mechanisms,but they arise mainly due to poor habitat conditions,improper tree species selections,mismatch between stands and habitat,extensive forest management measures,and human *** restoration and improvement of LEASFs are hindered by water deficits,mismatch between stands and habitat,single management purpose,and low *** are becoming more complex due to their wide range,the challenges associated with their restoration,and insufficient technological measures for their *** key techniques of the quality and efficiency improvement of LEASFs include basic forest tending methods,near-natural restoration,multifunction-oriented improvement,and systematic *** understanding on the formation mechanisms of LEASFs and a scientific approach toward their restoration are urgently needed and critical for the ecological protection and high-quality development of LEASFs on the *** on these analyses,we recommend strengthening the monitoring and supervision of LEASFs,considering the bearing capacity of regional water resources,implementing multiple restoration techniques,promoting multifunction-oriented ecological development,and exploring new management concepts to achieve the sustainable development of ASFs on the CLP.

关键词： low-efficiency artificial shelter forests restoration forest management multifunctional forestry near-natural forestry Three-North Shelter Forest Chinese Loess Plateau

Recent advances of hydrogen production through particulate semiconductor photocatalytic overall water splitting

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Frontiers in Energy 2022年第1期16卷 49-63页

作者： Zhi JIANG Zhen YE Wenfeng shangguan Research Center for Combustion and Environment Technology Shanghai Jiao Tong UniversityShanghai 200240China

Solar energy-driven photocatalytic water splitting has been investigated for decades to produce clean and renewable green *** this paper,the cutting-edge research within the overall water splitting system is summarized from the one-step photocatalytic overall water splitting(POWS)system to the two-step system and the cocatalysts research in this *** addition,the photocatalytic reaction engineering study is also reviewed which is crucial for future *** mini-review provides a picture of survey of recent progress of relevant overall water splitting system,with particular attention paid to material system and mechanistic breakthroughs,and highlights the challenge and opportunity of the current system.

关键词： photocatalysis overall water splitting hydrogen

On total chromatic number of planar graphs without 4-cycles

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Science China Mathematics 2007年第1期50卷 81-86页

作者： Min-le shangguan College of Mathematics Physics and Information Engineering Zhejiang Normal University

Let G be a simple graph with maximum degree Δ(G) and total chromatic number x ve (G). Vizing conjectured that Δ(G) + 1 ? X ve (G) ? δ(G) + 2 (Total Chromatic Conjecture). Even for planar graphs, this conjecture has not been settled yet. The unsettled difficult case for planar graphs is Δ(G) = 6. This paper shows that if G is a simple planar graph with maximum degree 6 and without 4-cycles, then x ve (G) ? 8. Together with the previous results on this topic, this shows that every simple planar graph without 4-cycles satisfies the Total Chromatic Conjecture.

关键词： total chromatic number planar graph F 5-subgraph 05C40

Leaf C:N:P stoichiometric homeostasis of a Robinia pseudoacacia plantation on the Loess Plateau

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Journal of Forestry Research 2023年第4期34卷 929-937页

作者： Zhuoxia Su Bingqian Su Shenglin Mao Zhouping shangguan State Key Laboratory of Soil erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100ShaanxiPeople’s Republic of China

Homeostasis is the adaptability of a species to a changing ***,the ecological stoichiometric homeostasis of Robinia pseudoacacia *** diff erent climatic regions is poorly understood but could provide insights into its adaptability in the loess hilly *** study sampled 20 year-old *** plantations at 10 sites along a north–south transect on the Loess *** in the ecological stoichiometric characteristics of leaf and soil carbon,nitrogen,and phosphorus were analysed and homeostatic characteristics of leaf ecological stoichiometric parameters in diff erent climates were identifi *** aff ecting leaf stoichiometry were *** results show that *** leaves were rich in nitrogen and defi cient in phosphorous during tree growth and *** and phosphorous levels in the soils of the loess region were lower than the average in soils in the rest of *** ecological stoichiometric parameters of *** leaves in two diff erent climates were considered“strictly homeostasis”.Precipitation,available phosphorus,and soil C:P were the main factors aff ecting the variation of C:N:P stoichiometry of *** *** in the loess hilly region has strong ecologically homeostatic characteristics and suggests that it is well-adapted to the area.

关键词： Loess Plateau Robinia pseudoacacia Ecological stoichiometry Homeostasis

Supplier Development under Supply Risk and Reputational Risk

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 360-388页

作者： Zhaowei Miao Yu Wang Rongjing Zhu Lili shangguan School of Management Xiamen UniversityXiamen361005China School of Economics and Management Tsinghua UniversityBeijing100084China

This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local *** reduce dependence on global suppliers and improve supply stability,we develop a differential game model to investigate the optimal investment decisions of the OEM towards the local supplier under different risk scenarios and the impact of different risks on the optimal *** results show that investment efficiency and risks have a significant impact on OEM investment ***,when the OEM has higher investment efficiency,investing in the local supplier is profitable for the OEM;conversely,when the investment efficiency of the OEM is lower,it does not *** addition,an increase in the supply risk of the global supplier will lower the entry threshold for OEM investment,but an increase in the supply risk of the local supplier and the reputational risk of both will increase this threshold,meaning that only the OEM with significantly higher investment efficiency can profit.

关键词： Supplier investment supplier development supply risk reputational risk dual sourcing

Species Composition, Richness and Aboveground Biomass of Natural Grassland in Hilly-Gully Regions of the Loess Plateau, China

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Journal of Integrative Agriculture 2014年第11期13卷 2527-2536页

作者： DENG Lei shangguan Zhou-ping State Key Laboratory of Soil erosion and Dryland Farming on the Loess Plateau Northwest A&F University

In order to study the characteristics of species composition, richness and aboveground biomass of natural grasslands, and then ifnd out the relations between species richness and aboveground productivity of the communities and possible mechanisms to form the relations, four typical grassland communities （Artemisia capillaries （AC）, Thymus quinquecostatus （TQ）, Stipa bungeana （SB） and Stipa grandis （SG）） along with a succession sequence in hilly-gully regions of the Loess Plateau, China, were investigated by ifeld survey and laboratory analysis. The results were summarized as follows：Different succession stages had different species compositions as well as different proportions of plant life forms and photosynthetic types, and Asteraceae, Poaceae and Leguminosae were their dominant species as well as their dominant perennial herb species;and different succession stages had signiifcantly different species richness and aboveground biomasses. There were many relation patterns （linear positive correlation, unrelated relations and unimodal relations） between the species richness and aboveground biomass in different succession stages and a signiifcant unimodal relation between the species richness and aboveground biomass in all the grassland communities and the highest species diversity appeared at a moderate level of productivity. The results suggest the unimodal relations in all the grassland communities are accumulative results of the relations in each succession stage.

关键词： life forms photosynthetic types productivity species diversity

Simulating the vegetation-producing process in small watersheds in the Loess Plateau of China

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Journal of Arid Land 2012年第3期4卷 300-309页

作者： KaiBo WANG ZhouPing shangguan State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an710075 China Northwest Agriculture and Forestry University Yangling 712100 China

Small watersheds are the basic composition unit of the Loess Plateau in China. An accurate estimation of vegetation net primary productivity （NPP） is of great significance for eco-benefit evaluation in small watershed management in this region. Here we describe the development and testing of a vegetation-producing process model （VPP） of a small watershed in the Loess Plateau. The model couples three modules： radiation adjustment; soil hydrological processes; and vegetation carbon assimilation. Model validation indicates that the VPP model can be used to estimate the NPP of small watersheds in the region. With the VPP model, we estimated the spatial NPP distributions in the Yangou watershed for 2007. The results show that in the Yangou watershed the NPP is relatively low, averaging 168 g C/（m^2.a）. Trees and shrubs have a higher NPP than crops and grasses. The NPP is larger on the partly shaded and shaded slopes than on the partly sunny and sunny slopes. The NPP on the slopes increases gradually on 0-20° slopes and decreases slightly on slopes steeper than 20°. Our simulation indicates that the vegetation type is the most important factor in determining the NPP distribution in small watersheds in the Loess Plateau.

关键词： small watershed net primary productivity vegetation-producing process model solar radiation soil hydrologicalprocess vegetation carbon assimilation

Dynamics of forest biomass carbon stocks from 1949 to 2008 in Henan Province,east-central China

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Journal of Forestry Research 2018年第2期29卷 434-443页

作者： Yanfang Wang Ling Liu Zhouping shangguan State Key Laboratory of Soil erosion and Dryland Farming on the Loess Plateau Northwest A&F University College of Agriculture Henan University of Science and Technology

We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,*** to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub *** estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor *** used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub *** the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10;g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 *** stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub *** storageincreased at an average annual rate of 0.8 Tg carbon over the study *** was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory ***-leaved forest was the main contributor to forest carbon *** 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 *** results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.

关键词： Forest biomass carbon stock Forest resource inventory Henan Province