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Assessing vegetation community distribution characteristics and succession stages in mountainous areas hosting coming Winter Olympics Games

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Journal of Mountain Science 2021年第11期18卷 2870-2887页

作者： zha.G heng-shuo zha.Tong-gang YU Yang JI Xiao-dong JESÚS Rodrigo-Comino School of Soil and Water Conservation Beijing Forestry UniversityQinghua East Road 35Beijing 100083China Jixian National Forest Ecosystem Research Network Station CNERNBeijing Forestry UniversityBeijing 100083China Departamento de Análisis Geográfico Regional y Geografía Física Facultad de Filosofía y LetrasCampus Universitario de CartujaUniversity of Granada18071 GranadaSpain

Alpine mountain ecosystem shows strong interactions between abiotic and biotic *** also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturbance risk areas in alpine mountains are increasing,it is necessary to understand the relationship between environmental factors and plant *** is also the key consideration for the coming international events such as the Winter Olympic Games,which could generate uncontrolled ecosystem issues not previously *** Yin Mountains in Chongli district,zha.gjiakou City,Hebei Province,China will be the core area of the 2022 Winter Olympic *** hypothesize that disturbances will be caused,therefore,the previous relationships between the habitat factors and plant community and the main environmental limiting factors before hosting them must be assessed to design future restoration ***,we used the two-way indicator species analysis(TWINSPAN)and market basket analysis(MBA)for vegetation classification in 91 sampling *** community and relationships among environmental variables(altitude,slope position,aspect,direction,inclination,soil porosity,soil bulk density,organic matter content and soil pH)were investigated through the trend correspondence(DCA)and canonical correspondence analyses(CCA).Also,the TWINSPAN was used to classify the vegetation into 6 different *** analysis showed that i)the spatial variation of soil moisture and the content of soil organic matter are the main factors limiting the development of shrub and herb communities;ii)the distribution of different forest communities was mainly affected by terrain factors(altitude,aspect and slope position);iii)the dynamic changes of vegetation communities in different altitudes were affected by the fluctuation of environmental factors and human disturbance,and the shrubs and herbaceous plants in mid-to-high altitude areas(above 1400 m)generally show the process o

关键词： Vegetation classification Topographic factors Community distribution Winter Olympic Games

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Research on Embedding Capacity and Efficiency of Information Hiding Based on Digital Images

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International Journal of Intelligence Science 2013年第2期3卷 77-85页

作者： Yanping zha.g Juan Jiang Yongliang zha.heng zha.g Shu zha. School of Computer Science and Technology Anhui University Hefei China

Generally speaking, being an efficient information hiding scheme, what we want to achieve is high embedding capacity of the cover image and high visual quality of the stego image, high visual quality is also called embedding efficiency. This paper mainly studies on the information hiding technology based on gray-scale digital images and especially considers the improvement of embedding capacity and embedding efficiency. For the purpose of that, two algorithms for information hiding were proposed, one is called high capacity of information hiding algorithm (HCIH for short), which achieves high embedding rate, and the other is called high quality of information hiding algorithm (HQIH for short), which realizes high embedding efficiency. The simulation experiments show that our proposed algorithms achieve better performance.

关键词： Information Hiding Embedding Capacity Embedding Efficiency Security Peak-Signal-to-Noise-Rate(PSNR)

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Fabrication of High-Quality Niobium Superconducting Tunnel Junctions

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Chinese Physics Letters 2011年第8期28卷 289-292页

作者： XU Qin-Yin CAO Chun-Hai LI Meng-Yue JIANG Yi zha.Shi-Tong KANG Lin XU Wei-Wei CHEN Jian WU Pei-heng Research Institute of Superconductor Electronics(RISE) Nanjing UniversityNanjing 210093

For high-quality superconducting tunnel junctions(STJs),it is necessary to reduce leakage current as much as *** describe the fabrication of niobium STJs using the selective niobium(Nb)etching process and various ways to minimize the leakage *** experiment shows that the leakage current mainly comes from shorts in the tunnel barrier layer rather than those around the junction *** systematic analysis of the thin film stress,surface morphology and modified junction structures,we fabricate high-quality Nb STJs with a gap voltage of 2.8 mV and a leakage current at 1 mV as low as 8.1%and 0.023%at 4.2 K and 0.3 K,respectively.

关键词： leakage tunnel film

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In-Situ SRPES Study on the Band Alignment of (0001)CdS/CdTe Heterojunction

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Chinese Physics Letters 2012年第5期29卷 201-204页

作者： GAO Jun-Ning JIE Wan-Qi YUAN Yan-Yan zha.Gang-Qiang XU Ling-Yan WU heng WANG Ya-Bin YU Hui ZHU Jun-Fa State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029

The band alignment of a (0001)CdS/CdTe heterojunction is in situ studied by synchrotron radiation photoemission spectroscopy (SRPES).The heterojunction is formed through stepwise deposition of a CdTe film on a wurtzite (0001)CdS single crystalline substrate via molecular beam *** shows an upward band bending of 0.55 eV,the valence band offset △Ev is calculated to be 0.65 e V and the conduction band offset △ Ec is 0.31 *** interracial band alignment is sketched to display type-Ⅰ band alignment.

关键词： alignment sketch bending

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Individual and joint effects of borderline ankle-brachial index and high plasma total homocysteine on all-cause death in hypertensive adults

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Journal of Geriatric Cardiology 2022年第7期19卷 522-530页

作者： Jun-Pei LI Tian-Yu CAO Xiao-Yuan zha.Yun YU Zi-heng TAN Zai-Hua Cheng Hua-Bo YING Wei ZHOU Lin-Juan ZHU Tao WANG Li-Shun LIU Hui-Hui BAO Xiao HUANG Xiao-Shu Cheng Department of Cardiology the Second Affiliated Hospital of Nanchang UniversityNanchangChina University of California Santa BarbaraCAUSA Rancheng Community Health Service Center WuyuanChina Center for Prevention and Treatment of Cardiovascular Diseases the Second Affiliated Hospital of Nanchang UniversityNan-changChina Graduate School at Shenzhen Tsinghua UniversityShenzhenChina

BACKGROUND The cardiovascular hazards of total homocysteine(tHcy)are long *** addition,despite the acknow-ledgment on the importance of low ankle-brachial index(ABI)(<0.9),borderline ABI(0.91-0.99)was once commonly *** study aims to explore the independent and joint effect of tHcy level and borderline ABI on all-cause death in hypertensive *** This study included 10,538 participants from China H-type Hypertension Registry *** was described into two groups:normal ABI(1.00-1.40)and borderline *** level was also divided into two groups:<15.02 and≥15.02μmo/*** groups were analyzed,using COX proportional hazard regression model,separately and pairwise to observe the independ-ent and joint effect on all-cause *** A total of 126(1.2%)deaths were observed in the 1.7 years follow-up *** ABI has a higher predicted risk of death than normal ABI(HR=1.87,95%CI:1.17-3.00)after adjusting for potential *** with tHcy level<15.02μmo/L(low tHcy),those with tHcy≥15.02μmo/L(high tHcy)had higher risk to event outcome(HR=1.99,95%CI:1.30-3.05).According to the cumulative hazard curve,group with borderline ABI and high tHcy level has significantly higher altitude and larger increasing rate over follow-up period compare to other *** those with borderline ABI,participants with high tHcy had higher death risk than those with low tHcy,nevertheless,no significant different between borderline and normal ABI among those with low tHcy *** Borderline ABI and tHcy level both have independent predictive value on all-cause *** combined group of borderline ABI and high tHcy has highest risk factor of outcomes,which suggested the mutual additive value of border-line ABI and *** attention should be given to the importance of borderline ABI in hypertensive population,especially with elevated tHcy level.

关键词： hypertensive death ankle

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Theoretical analysis and experimental verification of thermal decomposition mechanism of CuSe

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Transactions of Nonferrous Metals Society of China 2022年第10期32卷 3478-3486页

作者： Huan LUO heng XIONG Wen-long JIANG Lang LIU Guo-zheng zha.Tian-tian ZHEN Bin YANG Bao-qiang XU National Engineering Research Center of Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Yunnan Provincial Key Laboratory for Nonferrous Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Non-Ferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China

Experiments on the thermal decomposition of CuSe were carried out by using a thermogravimetric analyzer(TGA)at different heating *** kinetic parameters and mechanisms were discussed based on model-free and model-based *** decomposition rate and decomposition behavior of CuSe were investigated by using a vacuum thermogravimetric *** results showed that the R3 model was identified as the most probable mechanism function under the present experimental *** average values of activation energy and the pre-exponential factor were 12.344 J/mol and 0.152 s^(−1),*** actual decomposition rate of CuSe was found to be 0.0030 g/(cm^(2)·min).

关键词： CuSe thermal decomposition non-isothermal kinetics mechanism

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中国东部油气区的资源潜力

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石油学报 2003年第5期24卷 1-3,9页

作者：查全衡何文渊中国石油天然气集团公司咨询中心北京100724

东部油气区是中国最重要的石油生产基地。经过 40多年的勘探开发后 ,其生产潜力是一个备受关注的问题。对东部油气区钻探程度、储量年增长曲线、储量发现率曲线和资源探明率 4项指标进行了分析 ,充分考虑了本区实际存在的勘探目标和资... 详细信息

东部油气区是中国最重要的石油生产基地。经过 40多年的勘探开发后 ,其生产潜力是一个备受关注的问题。对东部油气区钻探程度、储量年增长曲线、储量发现率曲线和资源探明率 4项指标进行了分析 ,充分考虑了本区实际存在的勘探目标和资源潜力 ,初步提出了适合我国国情的勘探分期标准。依据 4项指标将本区勘探领域分为老区生产层系和新区与老区新层系两大类。研究结果表明 ,前一类处于勘探中期 ,储量可以持续稳定增长 ;后一类处于勘探早期。

关键词：中国东部油气区资源潜力勘探目标勘探阶段分期指标

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基于多传感器信息决策级融合的刀具磨损在线监测

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兵工学报 2021年第9期42卷 2024-2031页

作者：李恒叶祖坤查文彬王禹林南京理工大学计算机科学与技术学院江苏南京210094 中国船舶集团有限公司第七○五研究所昆明分部云南昆明650106 南京理工大学机械工程学院江苏南京210094

针对无法精确掌控机械加工过程中刀具磨损状态的现状,提出一种基于多传感器信息决策级融合的刀具磨损在线动态监测模型。该模型对采集的振动、力、声发射传感器信号进行特征提取后,将特征按传感器类型划分为独立样本。划分后的独立样本... 详细信息

针对无法精确掌控机械加工过程中刀具磨损状态的现状,提出一种基于多传感器信息决策级融合的刀具磨损在线动态监测模型。该模型对采集的振动、力、声发射传感器信号进行特征提取后,将特征按传感器类型划分为独立样本。划分后的独立样本分别对同一个刀具磨损量进行回归预测,进而对每一个独立样本预测得到的刀具磨损量进行加权综合决策,最终决策出刀具磨损量。实验结果表明:刀具磨损在线动态监测模型能够有效地提高刀具磨损动态预测精度,平均预测准确率可达97.9%;与现有研究方法相比,预测准确率至少提升4%以上,预测时间仅为0.016 s,具有较大优势。

关键词：刀具磨损在线监测信息决策级融合多层神经网络特征提取

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分阶段风险投资中再谈判行为与道德风险问题

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系统工程 2018年第12期36卷 83-96页

作者：查博张恒孙晓辉西安翻译学院创新创业学院陕西西安710105

探讨了分阶段风险投资中创业企业面对不完全资本市场和风投公司面对道德风险及不确定性时的模型,分析了分阶段投资在模型中作用。在对比初期一次性投资和分阶段投资后,结合再谈判行为的特性,发现了一些有意义的结论:不管在第二阶段有没... 详细信息

探讨了分阶段风险投资中创业企业面对不完全资本市场和风投公司面对道德风险及不确定性时的模型,分析了分阶段投资在模型中作用。在对比初期一次性投资和分阶段投资后,结合再谈判行为的特性,发现了一些有意义的结论:不管在第二阶段有没有再谈判行为,随着创业企业努力成本的提升,风投公司的利润水平在分阶段投资时会接近最优情况。不管在第二阶段有没有再谈判行为,随着创业企业努力成本的提升,分阶段投资中的努力水平(无论次优方案还是最优方案)都要高于初期一次性投资中的努力水平,并且次优方案中的努力水平会接近最优方案中的努力水平。对创业企业来讲,当第二阶段没有再谈判行为时,所有情况(次优方案和最优方案)下的最优股权都相同;当存在再谈判行为时,次优股权分配要高于最优股权分配。通过对创业板上市公司公布数据的实证分析,也验证了以上结论的正确性。

关键词：风险投资分阶段再谈判行为道德风险

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三聚磷酸二氢铝的生产及其在涂料中的应用

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现代涂料与涂装 2013年第9期16卷 28-32页

作者：张亨锦西化工研究院辽宁葫芦岛125000

介绍了三聚磷酸二氢铝的理化性质、发展现状及生产方法。综述了国内三聚磷酸二氢铝的粉体化、表面改性及防腐涂料应用研究情况。

关键词：三聚磷酸二氢铝性质生产改性应用研究进展

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