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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data

Journal of Integrative Agriculture 2024年第4期23卷 1164-1178页

作者： yunping chen Jie Hu Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu Macro Agriculture Research Institute College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China International Food Policy Research Institute NWWashingtonD.C.20005USA

Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural ***,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy *** this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)*** PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature *** on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover ***,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice ***,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively

关键词： ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data

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“互联网+医疗”模式在肺癌术后肺康复患者的应用效果研究

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中国现代医生 2024年第8期62卷 17-19,63页

作者：双小燕陈柳陈云萍季媛江西省肿瘤医院胸部肿瘤外科江西南昌330029 江西省肿瘤医院麻醉手术室江西南昌3300291

目的探讨“互联网+医疗”模式在肺癌术后肺康复患者的应用效果。方法选取笔者医院2022年6月至2023年1月接受择期肺癌手术治疗的87例肺癌患者,按随机数字表法分为对照组44例与观察组43例;对照组行常规干预,观察组行基于“互联网+医疗”... 详细信息

目的探讨“互联网+医疗”模式在肺癌术后肺康复患者的应用效果。方法选取笔者医院2022年6月至2023年1月接受择期肺癌手术治疗的87例肺癌患者,按随机数字表法分为对照组44例与观察组43例;对照组行常规干预,观察组行基于“互联网+医疗”模式干预;对比两组肺功能指标[用力肺活量(forced vital capacity,FVC)、第1秒用力肺活量(first second forced vital capacity,FEV1)、呼吸流量(respiratory flow,PEF)]、心肺耐力水平[6min步行试验(6min walking test,6MWT)]、呼吸劳累感及生活质量[世界卫生组织生存质量测定简表(World Health Organization quality of life,WHOQOL-BREF)]。结果干预6个月,研究组FVC、FEV1、PEF、6MWT距离、WHOQOL-BREE评分均较对照组高,呼吸疲劳感评分较对照组低,差异有统计学意义(P<0.05)。结论肺癌术后康复患者采用“互联网+医疗”模式干预可改善肺功能,提高心肺耐力,减轻呼吸疲劳感,提升生活质量。

关键词：肺癌互联网医疗肺康复

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Multiclassification algorithm and its realization based on least square support vector machine algorithm

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Journal of Systems Engineering and Electronics 2005年第4期16卷 901-907页

作者： Fan Youping chen yunping Sun Wansheng Li Yu Inst. of Bulk Grid Secttrity Faculty of Electrical Engineering Wuhan Univ. Wuhan 430072 P. R. China Automation Coll. Chongqing Univ. Chongqing 400044 P. R. China

As a new type of learning machine developed on the basis of statistics learning theory, support vector machine （SVM） plays an important role in knowledge discovering and knowledge updating by constructing non-linear optimal classifter. However, realizing SVM requires resolving quadratic programming under constraints of inequality, which results in calculation difficulty while learning samples gets larger. Besides, standard SVM is incapable of tackling multi-classification. To overcome the bottleneck of populating SVM, with training algorithm presented, the problem of quadratic programming is converted into that of resolving a linear system of equations composed of a group of equation constraints by adopting the least square SVM（LS-SVM） and introducing a modifying variable which can change inequality constraints into equation constraints, which simplifies the calculation. With regard to multi-classification, an LS-SVM applicable in multi-dassiftcation is deduced. Finally, efficiency of the algorithm is checked by using universal Circle in square and twospirals to measure the performance of the classifier.

关键词： control theory & control engineering artificial intelligence machine learning support vector machine.

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Spatio-temporal Dynamic Evolution and the Factors Impacting Eco-efficiency in chengdu-Chongqing Economic Circle

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Journal of Resources and Ecology 2022年第6期13卷 986-998页

作者： LI Hongli chen yunping Institute of Jiangxi Economic Development Jiangxi Normal UniversityNanchang 330224China School of Finance JiangxiNormal UniversityNanchang330224China

In response to the 14th National Five-year Plan of China and to better explore new strategies for promoting regional coordinated green development, the eco-efficiency values of chengdu-Chongqing Economic Circle and the corresponding temporal analysis from 2004 to 2018 were assessed in this paper using the super-SBM model and Markov chain. Meanwhile, the spatial analysis of eco-efficiency was conducted by a geographically weighted regression model. Although eco-efficiency has risen at an increasing rate, the economic development of chengdu-Chongqing Economic Circle was still ecologically ineffective. This means there is an urgent need to improve the efficiency of resource utilization and promote technological innovation. During the study period, the evolution of the eco-efficiency presented as a “π” shape, and was accompanied by the phenomenon of “club convergence”. There was also a strong tendency for eco-efficiency to maintain the original status quo, which indicates that it lacked sufficient momentum for improvement, so it was difficult to achieve a leapfrog transfer. Spatially, the eco-efficiency was distributed from northwest to southeast in a high-low-high manner. The spatial-temporal differences of eco-efficiency narrowed but the effect of agglomeration was relatively weak and there was a polarization trend. Further investigation suggests that the differences in the development level of urbanization, opening, technology, environmental regulation and advancement of industrial structure led to the spatial differences of eco-efficiency. Each city in the Economic Circle should make every effort to improve eco-efficiency accordingly, and thus to promote the green development of the whole region, so as to lay a foundation for driving the green and coordinated development of the central and western regions.

关键词： super SBM model Markov chain spatial and temporal disparities geographically weighted regression

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Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas

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Journal of Mountain Science 2024年第5期21卷 1647-1662页

作者： ZHANG yunping LIN Jianping HUANG Yimin chen Zebin ZHU chenhui YUAN Hao School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Key Laboratory of Low Carbon Recycling Technology for Municipal Solid Waste in Jiangxi Province Ganzhou 341000China

With rapid economic development,the size of urban land in China is expanding *** Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban *** delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the *** is of practical significance for the construction of green urban *** study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)*** the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final *** results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability *** results of convex hull model show that the urban expansion type of Nankang is *** the future,the urban expansion will mainly occur in the northern part of the *** PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated *** final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study *** results of the delineation can promote

关键词： Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development

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风险指标在提高传输功率极限中的应用

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高电压技术 2006年第7期32卷 105-108页

作者：徐箭陈允平武汉大学电气工程学院武汉430072

针对现有风险模型考虑系统稳定性过于简单的缺点,在实用动态安全域的基础上提出了一种新的风险指标并将它应用到提高输电线路传输功率极限的计算中,综合考虑超极限运行的经济效益和故障后的紧急控制成本,确定系统最佳运行点。该指标采... 详细信息

针对现有风险模型考虑系统稳定性过于简单的缺点,在实用动态安全域的基础上提出了一种新的风险指标并将它应用到提高输电线路传输功率极限的计算中,综合考虑超极限运行的经济效益和故障后的紧急控制成本,确定系统最佳运行点。该指标采用事故发生的概率来考虑其不确定性,利用紧急控制成本来衡量失稳事故的严重性。以江苏电网为例的验算结果表明,采用该风险指标确定的系统运行点能有效协调系统运行的安全性与经济性要求,经济、社会效益可观。

关键词：风险指标实用动态安全域紧急控制成本输电线路传输功率极限

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A mutation in TBXT causes congenital vertebral malformations in humans and mice

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Journal of Genetics and Genomics 2024年第4期51卷 433-442页

作者： Shuxia chen yunping Lei Yajun Yang chennan Liu Lele Kuang Li Jin Richard HFinnell Xueyan Yang Hongyan Wang Obstetrics and Gynecology Hospital State Key Laboratory of Genetic Engineering at School of Life SciencesKey Laboratory of Reproduction Regulation of NPFPCInstitute of Reproduction and DevelopmentFudan UniversityShanghai 200438China Shanghai Key Laboratory of Metabolic Remodeling and Health Institute of Metabolism and Integrative BiologyFudan UniversityShanghai 200438China Center for Precision Environmental Health Department of Molecular and Cellular BiologyBaylor College of MedicineHoustonTX 77030USA MOE Key Laboratory of Contemporary Anthropology School of Life SciencesFudan UniversityShanghai 200438China Department of Assisted Reproduction Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China Children’s Hospital Fudan University399 Wanyuan RoadShanghai 201102China

T-box transcription factor T(TBXT;T)is required for mesodermal formation and axial skeletal *** it has been extensively studied in various model organisms,human congenital vertebral malformations(CVMs)involving T are not well ***,we report a family with 15 CVM patients distributed across 4 *** affected individuals carry a heterozygous mutation,T c.596A>G(p.Q199R),which is not found in unaffected family members,indicating co-segregation of the genotype and *** vitro assays show that T p.Q199R increases the nucleocytoplasmic ratio and enhances its DNA-binding affinity,but reduces its transcriptional activity compared to the *** determine the pathogenicity of this mutation in vivo,we generated a Q199R knock-in mouse model that recapitulates the human CVM *** heterozygous Q199R mice show subtle kinked or shortened tails,while homozygous mice exhibit tail filaments and severe vertebral ***,we show that the Q199R mutation in T causes CVM in humans and mice,providing previously unreported evidence supporting the function of T in the genetic etiology of human CVM.

关键词： Congenital vertebral malformation TBXT T gene Loss-of-function mutation

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电力市场环境下基于风险的电力系统安全评估

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高电压技术 2006年第3期32卷 96-98页

作者：徐箭陈允平武汉大学电气工程学院武汉430072

为研究电力市场环境下的安全问题,引入了风险指标的概念,将事故的严重后果以及市场环境下事故的不确定性都计入风险指标中,用量化风险指标衡量系统的安全水平。关于事故的严重性考虑了其对系统稳定的影响及事故后的经济影响。最后结合... 详细信息

为研究电力市场环境下的安全问题,引入了风险指标的概念,将事故的严重后果以及市场环境下事故的不确定性都计入风险指标中,用量化风险指标衡量系统的安全水平。关于事故的严重性考虑了其对系统稳定的影响及事故后的经济影响。最后结合西部系统合作协会(WSCC—9)系统,说明了该方法的应用。

关键词：电力市场安全评估风险指标 WSCC-9

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基于动态安全域的电力系统暂态稳定预防控制、紧急控制及其协调

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电力自动化设备 2009年第8期29卷 1-7页

作者：徐箭陈允平武汉大学电气工程学院湖北武汉430072

针对预防控制和紧急控制之间的互补性特点,建立了预防控制和紧急控制协调控制优化问题的数学模型,并在基于扩展等面积准则的动态安全域的基础上,提出了预防控制措施和紧急控制措施搜索算法以及协调控制的优化策略。在进行预防控制措施... 详细信息

针对预防控制和紧急控制之间的互补性特点,建立了预防控制和紧急控制协调控制优化问题的数学模型,并在基于扩展等面积准则的动态安全域的基础上,提出了预防控制措施和紧急控制措施搜索算法以及协调控制的优化策略。在进行预防控制措施搜索时,利用适应度函数解决了失稳模式冲突所带来的初始可行解难以求解的问题,全面反映了不同故障不同失稳模式的动态安全域交集的分布。提出的紧急控制措施搜索算法根据切机搜索过程中失稳模式的改变情况来改变最优切机点,避免了切机负效应的影响。最后在8机32节点的系统上进行的算例验证了所提方法的正确性。

关键词：动态安全域暂态稳定预防控制紧急控制协调

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Preheating-assisted solid-state friction stir repair of Al-Mg-Si alloy plate at different rotational speeds

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 725-736页

作者： Hui Wang Yidi Li Ming Zhang Wei Gong Ruilin Lai yunping Li State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Research Institute of Light Alloy Central South UniversityChangsha 410083China

Additive friction stir deposition(AFSD)is a novel structural repair and manufacturing technology has become a research hotspot at home and abroad in the past five *** this work,the microstructural evolution and mechanical performance of the Al-Mg-Si alloy plate repaired by the preheating-assisted AFSD process were *** evaluate the tool rotation speed and substrate preheating for repair quality,the AFSD technique was used to additively repair 5 mm depth blind holes on 6061 aluminum alloy *** results showed that preheat-assisted AFSD repair significantly improved joint bonding and joint strength compared to the control non-preheat substrate ***,increasing rotation speed was also beneficial to improve the metallurgical bonding of the interface and avoid volume *** preheating conditions,the UTS and elongation were positively correlated with rotation *** the process parameters of preheated substrate and tool rotation speed of 1000 r/min,defect-free specimens could be obtained accompanied by tensile fracture occurring in the substrate rather than the repaired *** UTS and elongation reached the maximum values of 164.2MPa and 13.4%,which are equivalent to 99.4%and 140%of the heated substrate,respectively.

关键词： additive friction stir deposition structural repair tool rotation speed Al alloy

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