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Sensitivity analysis of Biome-BGCMuSo for gross and net primary productivity of typical forests in China

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Forest Ecosystems 2022年第1期9卷 111-123页

作者： Hongge Ren Li Zhang Min yan xin Tian xingbo zheng Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Research Station of Changbai Mountain Forest Ecosystems Chinese Academy of SciencesAntu133613JilinChina

Background:Process-based models are widely used to simulate forest productivity,but complex parameterization and calibration challenge the application and development of these *** analysis of numerous parameters is an essential step in model calibration and carbon flux ***,parameters are not dependent on each other,and the results of sensitivity analysis usually vary due to different forest types and ***,global and representative sensitivity analysis would provide reliable information for simple ***:To determine the contributions of input parameters to gross primary productivity(GPP)and net primary productivity(NPP),regression analysis and extended Fourier amplitude sensitivity testing(EFAST)were conducted for Biome-BGCMuSo to calculate the sensitivity index of the parameters at four observation sites under climate gradient from ***:Generally,GPP and NPP were highly sensitive to C:Nleaf(C:N of leaves),Wint(canopy water interception coefficient),k(canopy light extinction coefficient),FLNR(fraction of leaf N in Rubisco),MRpern(coefficient of linear relationship between tissue N and maintenance respiration),VPDf(vapor pressure deficit complete conductance reduction),and SLA1(canopy average specific leaf area in phenological phase 1)at all observation *** sensitive parameters occurred at four observation sites within different climate *** and NPP were particularly sensitive to FLNR,SLA1 and Wint,and C:Nleaf in temperate,alpine and subtropical zones,***:The results indicated that sensitivity parameters of China's forest ecosystems change with climate *** found that parameter calibration should be performed according to plant functional type(PFT),and more attention needs to be paid to the differences in climate and *** findings contribute to determining the target parameters in field experiments and model calibration.

关键词： Sensitivity analysis Biome-BGCMuSo Productivity Regression analysis EFAST

Mechanism of Jianpi Qingchang Huashi Recipe in treating ulcerative colitis:A study based on network pharmacology and molecular docking

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World Journal of Clinical Cases 2021年第26期9卷 7653-7670页

作者： Lie zheng xin-Li Wen yan-Cheng Dai Department of Gastroenterology Shaanxi Hospital of Traditional Chinese MedicineShaanxi Provincial Hospital of Traditional Chinese MedicineXi’an 730000Shaanxi ProvinceChina Department of Gastroenterology Shanghai Traditional Chinese Medicine Integrated HospitalShanghai University of Traditional Chinese MedicineShanghai 200082China

BACKGROUND Ulcerative colitis(UC)is a refractory intestinal disease with alternating onset and remission and a long disease course,which seriously affects the health and quality of life of *** goal of treatment is to control clinical symptoms,induce and maintain remission,promote mucosal healing,and reduce *** trials have shown unsatisfactory clinical response *** a supplementary alternative medicine,traditional Chinese medicine has a rich history and has shown good results in the treatment of *** of the quality of herbal medicine and other factors,the curative effect of traditional Chinese medicine is not stable *** mechanism underlying the effect of Jianpi Qingchang Huashi Recipe(JPQCHSR)on inducing UC mucosal healing is not *** To investigate the potential mechanism of JPQCHSR for the treatment of UC based on network pharmacology and molecular *** Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform was used to extract the active components and action targets of JPQCHSR,and the target names were standardized and corrected through UniProt *** related targets of UC were obtained through GeneCards database,and the intersection targets of drugs and diseases were screened by jvenn online analysis *** visual regulatory network of"Traditional Chinese medicine-active components-target-disease"was constructed using Cytoscape software,the protein interaction network was constructed using STRING database,and enrichment analysis of gene ontology and Kyoto Encyclopedia of Genes and Genomes pathways was conducted through R *** last,the active components were docked with the core target through SYBYL-X 2.1.1 *** Through database analysis,a total of 181 active components,302 targets and 205 therapeutic targets were obtained for *** key compounds include quercetin,luteolin,kaempferol,*** core targets involved STAT3,AKT1,TP53,MAPK1,MAPK3,JUN,TNF,

关键词： Jianpi Qingchang Huashi Recipe Ulcerative colitis Network pharmacology Molecular docking Inflammatory disease

Influence of carrier concentration on the resistive switching characteristics of a ZnO-based memristor

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Nano Research 2016年第4期9卷 1116-1124页

作者： Yihui Sun Xiaoqin yan xin zheng Yichong Liu yanwei Shen Yue Zhang State Key Laboratory for Advanced Metals and Materials School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Municipal Key Laboratory of New Energy Materials and Technologies University of Science and Technology Beijing Beijing 100083 China

Sandwich-style memristor devices were synthesized by electrochemical deposition with a ZnO film serving as the active layer between Al-doped ZnO （AZO） and Au electrodes. The carrier concentration of the ZnO films is controlled by adding HNO3 during the growth process. A resulting increase in carrier concentration from 10^17 to 10^19 cm^-3 was observed, along with a corresponding drop in the on--off ratio from 6,437% to 100%. The resistive switching characteristics completely disappeared when the carrier concentration was above 1029 cm-3, making it unsuitable for a memory device. The decreasing switching ratio is attributed to a reduction in the driving force for oxygen vacancy drift. Systematic analysis of the migration of oxygen vacancies is presented, including the concentration gradient and electrical potential gradient. Such oxygen vacancy migration dynamics provide insight into the mechanisms of the oxygen vacancy drift and provide valuable information for industrial production of memristor devices.

关键词： resistive switch carrier concentration driving force potential gradient concentration gradient

Landslide susceptibility assessment using the certainty factor and analytic hierarchy process

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Journal of Mountain Science 2017年第5期14卷 906-925页

作者： FAN Wen WEI xin-sheng CAO yan-bo zheng Bin Department of Geological Engineering Chang'an University Xi'an 710054 China

A new approach combining the certainty factor(CF) and analytic hierarchy process(AHP) methods was proposed to assess landslide susceptibility in the Ziyang district, which is situated in the Qin-Ba Mountain region, China. Landslide inventory data were collected based on field investigations and remote sensing interpretations. A total of 791 landslides were identified. A total of 633 landslides were randomly selected from this data setas the training set, and the remaining landslides were used for validation as the test set. Nine factors, including the slope angle, slope aspect, slope curvature, lithology, distance to faults, distance to streams, precipitation, road network intensity degree and land use were chosen as the landslide causal factors for further susceptibility assessment. The weight of each factor and its subclass were calculated by AHP and CF methods. Landslide susceptibility was compared between the bivariate statistical method and the proposed CF-AHP method. The results indicate that the distance to streams, distance to faults and lithology are the most dominant causal factors associated with landslides. The susceptibility zonation was categorized into five classes of landslide susceptibility, i.e., very high, high, moderate, low and very low level. Lastly, the relative operating characteristics(ROC) curve was used to validate the accuracy of the new approach, and the result showed a satisfactory prediction rate of 78.3%, compared to 69.2% obtained with the landslide susceptibility index method. The results indicate that the CF-AHP combined method is more appropriate for assessing the landslide susceptibility in this area.

关键词： Ziyang district Landslide Certainty factor Analytic hierarchy process Susceptibility assessment ArcGIS

Non-negligible factors in low-pressure sprinkler irrigation:droplet impact angle and shear stress

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Journal of Arid Land 2022年第11期14卷 1293-1316页

作者： HUI xin zheng Yudong MUHAMMAD Rizwan Shoukat TAN Haibin yan Haijun College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Engineering Research Center of Agricultural Water-Saving and Water Resources Ministry of EducationBeijing 100083China Semi-arid Agriculture Engineering&Technology Research Center of China Shijiazhuang 050051China

Droplet shear stress is considered as an important indicator that reflects soil erosion in sprinkler irrigation more accurately than kinetic energy,and the effect of droplet impact angle on the shear stress cannot be *** this study,radial distribution of droplet impact angles,velocities,and shear stresses were investigated using a two-dimensional video disdrometer with three types of low-pressure sprinkler(Nelson D3000,R3000,and Komet KPT)under two operating pressures(103 and 138 kPa)and three nozzle diameters(3.97,5.95,and 7.94 mm).Furthermore,the relationships among these characteristical parameters of droplet were analyzed,and their influencing factors were comprehensively *** various types of sprinkler,operating pressures,and nozzle diameters,the smaller impact angles and larger velocities of droplets were found to occur closer to the sprinkler,resulting in relatively low droplet shear *** increase in distance from the sprinkler caused the droplet impact angle to decrease and velocity to increase,which contributed to a significant increase in the shear stress that reached the peak value at the end of the ***,the end of the jet was the most prone to soil erosion in the radial direction,and the soil erosion in sprinkler irrigation could not only be attributed to the droplet kinetic energy,but also needed to be combined with the analysis of its shear *** comparing the radial distributions of average droplet shear stresses among the three types of sprinklers,D3000 exhibited the largest value(26.94-3313.51 N/m^(2)),followed by R3000(33.34-2650.80 N/m^(2)),and KPT(16.15-2485.69 N/m^(2)).From the perspective of minimizing the risk of soil erosion,KPT sprinkler was more suitable for low-pressure sprinkler irrigation than D3000 and R3000 *** addition to selecting the appropriate sprinkler type to reduce the droplet shear stress,a suitable sprinkler spacing could also provide acceptable results,because the distance

关键词： center pivot irrigation system water droplet universal model soil erosion water-saving irrigation

Neural Dynamics for Distributed Collaborative Control of Manipulators With Time Delays

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IEEE/CAA Journal of Automatica Sinica 2022年第5期9卷 854-863页

作者： Long Jin xin zheng xin Luo School of Information Science and Engineering Lanzhou UniversityLanzhou 730000 IEEE State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

Time-delay phenomena extensively exist in practical systems,e.g.,multi-agent systems,bringing negative impacts on their *** work analyzes a collaborative control problem of redundant manipulators with time delays and proposes a time-delayed and distributed neural dynamics *** assumptions that the network topology is fixed and connected and the existing maximal time delay is no more than a threshold value,it is proved that all manipulators in the distributed network are able to reach a desired *** proposed distributed scheme with time delays considered is converted into a time-variant optimization problem,and a neural dynamics solver is designed to solve it ***,the proposed neural dynamics solver is proved to be stable,convergent and ***,the allowable threshold value of time delay that ensures the proposed scheme’s stability is *** examples and comparisons are provided to intuitively prove the validity of the proposed neural dynamics scheme and solver.

关键词： Distributed collaborative control neural dynamics redundancy resolution repetitive motion planning(RMP) time delay

A monolithic 3D IGZO-RRAM-SRAM-integrated architecture for robust and efficient compute-in-memory enabling equivalent-ideal device metrics

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Science China(Information Sciences) 2025年

作者： Shengzhe yan Zhaori CONG Zi WANG Zhuoyu DAI Zeyu GUO Zhihang QIAN Xufan LI Xu zheng Chuanke CHEN Nianduan LU Chunmeng DOU Guanhua yanG Xiaoxin XU Di GENG Jinshan YUE Lingfei WANG Ling LI Ming LIU Institute of Microelectronics of the Chinese Academy of Sciences University of Chinese Academy of Sciences

Abstract Compute-in-memory (CIM) based on various devices such as static random access memory (SRAM) and resistive random access memory (RRAM) and other emerging devices such as indium-gallium-zinc-oxide (IGZO) transistor, magnetoresistive RAM (MRAM), and ferroelectric RAM (FeRAM) has been explored for better performance and energy efficiency on neural networks applications. However, CIM based on a single-type device suffers a variety of non-ideal metrics to reach the simultaneous optimal accuracy, density, and energy efficiency. This work presents equivalent-ideal CIM (Eq-CIM), a monolithic 3D(M3D) IGZO-RRAM-SRAM integrated architecture for robust and efficient compute-in-memory enabling equivalent-ideal device metrics. To overcome the non-ideality (variation, endurance, temperature, etc.) of the single-type devices, system-technology co-optimization (STCO) is performed. This work highlights the non-ideality-aware functionality breakdown for robust high accuracy and simultaneous high density/efficiency, by utilizing 2T0C IGZO for temporal activation storage, RRAM for high-density weight storage, and SRAM for accurate CIM. Device-to-algorithm variation transfer is applied to analyze the system-level accuracy. We benchmark Eq-CIM architecture on CIFAR-10/ImageNet, with 5.06×storage density and 5.05×/2.45×area/energy efficiency compared with single-type-device-based CIM, and high robustness (<0.27%accuracy loss) from-40℃ to 120℃.

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Austenite grain growth of medium-carbon alloy steel with aluminum additions during heating process

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 282-290页

作者： Zi-yi Liu yan-ping Bao Min Wang xin Li Fan-zheng Zeng State key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Xiangtan Iron & Steel Co. Ltd.of Hunan Valin

In this study, the effects of heating temperature(850–1100°C) and holding time(30–150 min) on the grain growth behavior of austenite in medium-carbon alloy steel were investigated by conducting experiments. The abnormal grain growth and mixed grain structure phenomenon are explained using an equilibrium precipitation phase diagram calculated by Thermo-Calc software package. The Al N particles were observed by field-emission scanning electron microscopy(FESEM), and the amount of AlN precipitations was detected by electron probe microanalysis(EPMA). Based on the research results, it was found that the average grain size of austenite in the test steel increased continuously with the increase of temperature and holding time. Furthermore, the abnormal growth of austenite occurred in the test steel at 950°C, and the heating temperature affected the austenite grain size more significantly. In addition, the decline in the amount of AlN second-phase particle in the test steel, which weakened the "pinning" effect on austenite grain boundaries, resulted in abnormal growth and the development of mixed austenite grain structures. The prediction model for describing the austenite grain growth of medium-carbon alloy steel during heating was established by regression analysis of the experimental data, and the model was verified to be highly accurate.

关键词： alloy steel austenite grain AlN growth model

Assessment of internal quality of billets using ultrasonic three-dimensional layered characterization

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Journal of Iron and Steel Research International 2024年第11期31卷 2727-2739页

作者： yan-bo Liu Min Li zheng Zhao Zhong-xin Wang De-bin yang School of Mechanical Engineering University of Science and Technology BeijingBeijing100083China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China

To address the challenge of visualizing internal defects within castings, ultrasonic nondestructive testing technology has been introduced for the detection and characterization of internal defects in castings. Ultrasonic testing is widely utilized for detecting and characterizing internal defects in materials, thanks to its strong penetration ability, wide testing area, and fast scanning speed. However, traditional ultrasonic testing primarily relies on one-dimensional waveforms or two-dimensional images to analyze internal defects in billets, which hinders intuitive characterization of defect quantity, size, spatial distribution, and other relevant information. Consequently, a three-dimensional (3D) layered characterization method of billets internal quality based on scanning acoustic microscope (SAM) is proposed. The method starts with a layered focus scanning of the billet using SAM and pre-processing the obtained sequence of ultrasonic images. Next, the ray casting is employed to reconstruct 3D shape of defects in billets, allowing for characterization of their quality by obtaining characteristic information on defect spatial distributions, quantity, and sizes. To validate the effectiveness of the proposed method, specimens of 42CrMo billets are prepared using five different processes, and the method is employed to evaluate their internal quality. Finally, a comparison between the ultrasonic image and the metallographic image reveals a difference in dimensional accuracy of only 2.94%. The results indicate that the new method enables visualization of internal defect information in billets, serving as a valuable complement to the traditional method of characterizing their internal quality.

关键词： Internal quality of billets Ultrasonic testing Scanning acoustic microscope Layered characterization Three-dimensional reconstruction