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Plant Phenomics 2021年第1期3卷 57-64页

作者： Tianyi Kou Ji Ye Jing Wang Yan Peng Zefang Wang chenjun Shi Xu Wu Xitian Hu Haihong chen Ling Zhang xiaohong chen Yiming Zhu Huiliang Li Songlin Zhuang Terahertz Technology Innovation Research Institute Shanghai Key Lab of Modern Optical SystemTerahertz Science Cooperative Innovation CenterUniversity of Shanghai for Science and TechnologyShanghai Institute of Intelligent Science and TechnologyShanghaiChina Department of Pharmacy Second Military Medical UniversityShanghaiChina School of Pharmacy Nanjing Medical UniversityNanjingChina Shanghai Institute of Intelligent Science and Technology Tongji University ShanghaiChina

Panax quinquefolium is a perennial herbaceous plant that contains many beneficial ginsenosides with diverse pharmacological effects.24(R)-pseudoginsenoside F_(11)is specific to ***,a useful biomarker for distinguishing this species from other related ***,because of its nonconjugated property and the complexity of existing detection methods,this biomarker cannot be used as the identification *** herein present a stable 24(R)-pseudoginsenoside F_(11)fingerprint spectrum in the terahertz band,thereby proving that F_(11)can be detected and quantitatively analyzed via terahertz *** also analyzed the sample by high-performance liquid chromatography-triple quadrupole mass *** difference between the normalized data for the two analytical methods was less than 5%.Furthermore,*** from different areas and other substances can be clearly distinguished based on these terahertz spectra with a standard principal component *** method is a fast,simple,and cost-effective approach for identifying and quantitatively analyzing ***.

关键词： ginsenoside conjugated thereby

Review of Recent Progress in Robotic Knee Prosthesis Related Techniques:Structure,Actuation and Control

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Journal of Bionic Engineering 2021年第4期18卷 764-785页

作者： Yuanxi Sun Hao Tang Yuntao Tang Jia Zheng Dianbiao Dong xiaohong chen Fuqiang Liu Long Bai Wenjie Ge Liming Xin Huayan Pu Yan Peng Jun Luo State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China School of Mechanical Engineering Tianjin UniversityTianjin 300072China College of Mechanical Engineering Chongqing UniversityChongqing 400044China School of Advanced Manufacturing Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering Vrije Universiteit Brussel1050 BrusselsBelgium Department of Mechanical&Industrial Engineering University of TorontoToronto M5S 2E8Canada Research Institute of Unmanned Surface Vessel(USV)Engineering Shanghai UniversityShanghai 200444China

As the essential technology of human-robotics interactive wearable devices,the robotic knee prosthesis can provide above-knee amputations with functional knee compensations to realize their physical and psychological social *** the development of mechanical and mechatronic science and technology,the fully active knee prosthesis that can provide subjects with actuating torques has demonstrated a better wearing performance in slope walking and stair ascent when compared with the passive and the semi-active ***,with intelligent human-robotics control strategies and algorithms,the wearing effect of the knee prosthesis has been greatly enhanced in terms of stance stability and swing ***,to help readers to obtain an overview of recent progress in robotic knee prosthesis,this paper systematically categorized knee prostheses according to their integrated functions and introduced related research in the past ten years(2010−2020)regarding(1)mechanical design,including uniaxial,four-bar,and multi-bar knee structures,(2)actuating technology,including rigid and elastic actuation,and(3)control method,including mode identification,motion prediction,and automatic *** and qualitative analysis and comparison of robotic knee prosthesis-related techniques are *** development trends are concluded as follows:(1)bionic and lightweight structures with better mechanical performance,(2)bionic elastic actuation with energy-saving effect,(3)artificial intelligence-based bionic prosthetic ***,challenges and innovative insights of customized lightweight bionic knee joint structure,highly efficient compact bionic actuation,and personalized daily multi-mode gait adaptation are also discussed in-depth to facilitate the future development of the robotic knee prosthesis.

关键词： bionic robotic knee prosthesis prosthetic knee mechanism actuation control

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基于出行者稳定性的简化活动模型结构研究

华南理工大学学报（自然科学版） 2021年第2期49卷 59-67页

作者：陈先龙陈小鸿同济大学道路与交通工程教育部重点实验室上海201804 广州市交通规划研究院信息模型所广东广州510030

本研究回顾了国内外交通模型发展态势,归纳传统四步骤模型和基于活动的模型等各自的局限性,特别是既有交通规划模型在解释、提取出行者稳定性特征以改善模型精度方面的不足。基于大数据为新时代交通模型带来的机遇与挑战,阐述了利用移... 详细信息

本研究回顾了国内外交通模型发展态势,归纳传统四步骤模型和基于活动的模型等各自的局限性,特别是既有交通规划模型在解释、提取出行者稳定性特征以改善模型精度方面的不足。基于大数据为新时代交通模型带来的机遇与挑战,阐述了利用移动通信位置数据解决上述问题的可能性。针对出行者活动“端点—目的”的稳定性特征,定义了区别于传统四步骤模型中以基家和非基家为基础的出行目的分类,提出了充分利用出行者居住地、工作地(学校)和生活出行场所固定特点,区分稳态出行和偶然出行的简化活动模型,建立一种出行生成与出行分布联合计算的改进四步骤模型结构。以广州市花都区为例,对比分析了基于传统最优化模型的标准重力模型、K系数矩阵重力模型结果与稳态出行矩阵估计的差异。结果表明:最优化模型对城市稳态出行的解释存在不足,基于大数据的城市稳态出行特征分析结果更能反映城市交通活动的实际情况。最后,展望了未来更多出行者活动稳定性因素嵌入交通规划模型的可能性。

关键词：四步骤模型基于活动的模型出行者稳定性稳态出行偶然出行重力模型

The Carboniferous reefs in China

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Journal of Palaeogeography 2012年第1期1卷 27-42页

作者： Gong Enpu,Zhang Yongli,Guan Changqing,chen xiaohong Department of Geology,Northeastern University,Shenyang 110819,China Department of Geology Northeastern University Shenyang 110819 China

The Carboniferous period was a unique period for reef developments during the Late Paleozoic;however,in past years,studies dealing with the Carboniferous reefs in China were very *** recent years,the Carboniferous reefs were studied in detail and diverse types of reefs have been discovered in different areas of *** these areas,the Mississippian reefs were primarily built of bryozoans and rugose corals,which were associated with various kinds of calcareous *** the Pennsylvanian,in South China,the reef builders were composed of the rugose coral Fomichevella and phylloid algae,whereas in North China,the reef builders were composed of Chaetetes,bryozoans and *** are two main reef-building communities within Carboniferous reefs in China;an algal reef-building community and a reef-building community dominated by colonial *** evolutionary relationships between these two types of communities can be detected,thus indicating that two different linerages of reef-building communities evolved during the Carboniferous;the former community consists of cyanobacteria,bacteria and calcareous algae,while the latter one consists of various skeletal metazoan *** careful study of the developments of Chinese Carboniferous reefs,the evidence indicates that various communities of organisms played important reef-building functions during this *** occurrence of these metazoan framework reefs also indicates that,during the Carboniferous,most areas in China would have been dominated by the environments with a tropical or subtropical climate.

关键词： Carboniferous reef China evolution marine ecosystem

Purposeless repeated acquisition time-lapse seismic data processing

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Petroleum Science 2008年第1期5卷 31-36页

作者： Li Jingye chen xiaohong Zhao Wei Zhang Yunpeng Key Laboratory for Hydrocarbon Accumulation Mechanism Ministry of Education China University of PetroleumBeijing 102249 China Basin ＆ Reservoir Research Center China University of Petroleum Beijing 102249 China School of Resource and Information China University of Petroleum Beijing 102249 China Research Center of CNOOC Beijing 100027 China

In China, most oil fields are continental sedimentation with strong heterogeneity, which on one side makes the reservoir prospecting and development more difficult, but on the other side provides more space for searching residual oil in matured fields. Time-lapse seismic reservoir monitoring technique is one of most important techniques to define residual oil distribution. According to the demand for and development of time-lapse seismic reservoir monitoring in China, purposeless repeated acquisition time-lapse seismic data processing was studied. The four key steps in purposeless repeated acquisition time-lapse seismic data processing, including amplitude-preserved processing with relative consistency, rebinning, match filtering and difference calculation, were analyzed by combining theory and real seismic data processing. Meanwhile, quality control during real time-lapse seismic processing was emphasized.

关键词： Time-lapse seismic purposeless repeated acquisition rebinning match filtering amplitude-preserved processing

Regional Evaluations of the Meteorological Drought Characteristics across the Pearl River Basin, China

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American Journal of Climate Change 2012年第1期1卷 48-55页

作者： Qiang Zhang Mingzhong Xiao xiaohong chen Department of Water Resources and Environment Sun Yat-sen University Guangzhou China Key Laboratory of Water Cycle and Water Security in Southern China of Guangdong High Education Institute Sun Yat-sen University Guangzhou China School of Geography and Planning and Guangdong Key Laboratory for Urbanization and Geo-Simulation Sun Yat-sen University Guangzhou China

Regional evaluation of drought characteristics provides critical information for water resource management. In this case, this study attempts to analyze the probability behaviors of drought events of a given severity in the Pearl River Basin and to construct severity-area-frequency curves of drought events. Due to possible impacts of complicated topographical properties and diverse climate types within the Pearl River Basin, the entire Pearl River Basin is subdivided into different homogeneous regions. In general, the Pearl River Basin can be categorized into four homogeneous regions, and the severity-area-frequency analysis results for the short-, medium- and long-term drought episodes within each homogeneous regions indicate stressful challenge for the water resource management in the Pearl River Basin due to the fact that severe droughts usually occur over the entire Pearl River Basin. Meanwhile, the Pearl River Delta will face a higher risk of drought when compared to other regions of the Pearl River Basin in terms of the medium-term drought. The Pearl River Basin is highly economically development and is heavily populated, thus impacts of droughts and related resilience resolutions or policies should be taken into account in the formulation of regional sustainable development of water resources and socio-economy within the Pearl River Basin, China.

关键词： Regional Drought Severity-Area-Frequency Curves Cluster Algorithm The Pearl River Basin

Spatio-Temporal Variations of Precipitation Extremes in the Yangtze River Basin (1960-2002), China

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Atmospheric and Climate Sciences 2011年第1期1卷 1-8页

作者： Qiang Zhang xiaohong chen Becker Stefan 不详

Daily precipitation data during 1960-2002 from 150 stations in the Yangtze River basin were analyzed with the help of linear trend analysis. Highest 5-day and 10-day precipitation amount (R5D and R10D) and percentile daily precipitation maxima (prec95p for 95th percentile and prec99p for 99th percentile) were accepted as the precipitation extreme index. The frequency of the R5D and R10D was in downward trend, this phenomenon is more obvious in the middle Yangtze River basin;The stations with total precipitation of R5D and R10D are in significant upward trend (> 95% confidence level) are mostly located in the lower Yangtze River basin and the south-western part of the Yangtze River basin;2) the spatial distribution of the frequency of total precipitation of the percentile daily precipitation maxima is similar to that of R5D and R10D. However the frequency of prec95p and prec99p is in significant upward trend. The upward trend of total precipitation changes of prec95p and prec99p is more obvious than that of frequency of prec95p and prec99p. The regions dominated by upward trend of frequency/total precipitation of prec95p and prec99p are also the lower Yangtze River basin and south-western part of the Yangtze River basin. Therefore the occurrence probability of the flash floods in the lower Yangtze River basin and south-western part of the Yangtze River basin will be greater.

关键词： Extreme Precipitation Linear Trend Spatial Distribution Pattern Yangtze River Basin

An Empirical Research on the Evolution Model of Competitiveness Between Different Life Cycle Stages in Chinese Enterprises

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Journal of Systems Science and Information 2008年第4期6卷 351-370页

作者： xiaohong chen Yu Cao Yueru Ma School of Business Central South University Changsha 410083 China

The characteristic of enterprise competitiveness is different between different life cycle stages. In this paper we surveyed the enterprise competitiveness＇s differences in various stages of the life cycle and the evolution model of three aspects of enterprise com- petitiveness as resource, capability and dynamic capability by questionnaire survey. The result shows that there are significant differences between different life cycle stages of en- terprise competitiveness in China. The enterprise competitiveness is stronger and stronger during the periods from the enterprise＇s birth to maturity, while in the enterprise＇s recession period the competitiveness becomes much weaker. The competitiveness＇s constitutive features in each stage are as follows： in the enterprise＇s born stage the enterprise is lack of resources and its competition mainly relies on the ability; in the enterprise＇s growth stage the enterprise＇s resources become richer and are as important as enterprise＇s ability in the constitution of enterprise competitiveness; in the maturity stage the enterprise＇s people, money and material resources all become very rich but the role of capability in enterprise competitiveness begins to decrease; in the enterprise＇s recession stage the en- terprise resources begin to exhaust, and the enterprise＇s competitiveness returns to rely on capability, and in this period the enterprise＇s learning ability, innovation ability and dynamic mechanisms perform worst, which will affect the enterprise＇s revival and lead to the ultimate death of enterprise. These conclusions have great value for reference to the enterprise＇s competitive strategy making for different life cycle stages.

关键词： enterprise competitiveness evolution model empirical research life cycle

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基于可能度的交叉口信号控制区间优化模型

华南理工大学学报（自然科学版） 2022年第10期50卷 29-40页

作者：陈小红胡芳广西大学数学与信息科学学院/广西应用数学中心广西南宁530004 广西大学经济学院/中国-东盟金融合作学院广西南宁530004

为了满足城市道路不确定性交通需求,提高不确定环境下交通信号控制方案的可靠性,针对交通信号控制配时参数优化问题,结合区间优化理论提出了交叉口信号配时参数区间优化模型。首先,采用5 min采集标段确定高峰期交通量区间,并以此交通量... 详细信息

为了满足城市道路不确定性交通需求,提高不确定环境下交通信号控制方案的可靠性,针对交通信号控制配时参数优化问题,结合区间优化理论提出了交叉口信号配时参数区间优化模型。首先,采用5 min采集标段确定高峰期交通量区间,并以此交通量区间作为控制系统输入参数;其次,以交叉口机动车平均控制延误区间为目标函数,构建区间值信号配时参数非线性优化模型;再者,以交叉口服务水平为性能目标,利用区间可能度模型对区间值优化模型进行转换,并采用遗传算法求解;最后,运用VISSIM仿真软件分别对北京市典型的三相位与两相位交叉口晚高峰时段进行模拟仿真。结果表明,该配时参数区间优化模型可行、有效。对于交通量波动较大的三相位交叉口,该区间优化方法明显优于Webster方案、鲁棒优化方法、实测数据,平均延误和交叉口通行能力较实测结果的优化程度分别为26.57%与7.07%;对于交通量相对平稳的两相位交叉口,区间优化方法可行,且能达到预期控制效果,但均弱于其他方案。进一步,选取北京市东三环8个交叉口进行信号配时参数区间优化,以高峰时段内5 min采集标段的饱和度和车均延误的波动趋势来分析控制方案的稳定性。分析表明,区间优化方法对各个路口高峰时段间而言都能达到预期控制效果,且更适合于交通量波动相对较大的交叉口,其方案的控制效果更稳定。

关键词：城市交通交通信号控制交通量区间非线性区间优化区间可能度交叉口服务水平

Research on the ecological compensation standard of the basin pollution control project based on evolutionary game theory and by taking Xiangjiang River as a case

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Frontiers of Engineering Management 2019年第4期6卷 575-583页

作者： Dongbin HU Huiwu LIU xiaohong chen Yang chen School of Business Resource-Conserving&Environment-Friendly Society and Ecological Civilization 2011 Collaborative Innovation Center of Hunan ProvinceCentral South UniversityChangsha 410083China School of Business Central South UniversityChangsha 410083China Institute of Big Data and Internet Innovation Hunan University of Technology and BusinessChangsha 410205China

Ecological compensation is a new resource and environment management *** one of the main areas for implementing ecological compensation policies,basin ecological compensation has become an important measure for encouraging basin pollution control projects and improving the quality of regional economic *** applying the basic game analysis of evolutionary game theory and building an evolutionary game model with a“reward-punishment”mechanism,this paper compares the interest-related decision-making behaviors of the upstream and downstream stakeholders of basin ecological *** using data on the water quality of Xiangjiang River Basin,this paper calculates the rewards and penalties in different intervals by building a parametric regression mathematical model and employing the local linear regression *** show that a decline in water quality should be fined RMB 925500 yuan,an improvement in water quality should be awarded RMB 1227800 yuan,and a deteriorating water quality should be severely fined RMB 5087600 yuan.

关键词： evolutionary game ecological compensation standard Xiangjiang River Basin