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Estimating rice paddy areas in China using multi-temporal cloud-free normalized difference vegetation index (NDVI) imagery based on change detection

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Pedosphere 2020年第6期30卷 734-746页

作者： bolun li Chaopu TI Xiaoyuan YAN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The spatial pattern of rice paddies is an essential parameter used for studies of greenhouse gas emissions,agricultural resource management,and environmental *** large spatial scales,previous studies have usually mapped rice paddies using a single vegetation index product based on a traditional classification method,or a combined analysis of various vegetation and water indices derived from the moderate resolution imaging spectroradiometer(MODIS)satellite ***,different indices increase the computational cost and constrain the satellite data sources,and traditional classification methods(e.g.,maximum likelihood classification)may be time-consuming and difficult to carry out over a large area like *** this study,we designed an auto-thresholding and single vegetation index(normalized difference vegetation index(NDVI))-based procedure to estimate the spatial distribution of rice paddies in *** MOD09Q1 product,which was available at MODIS’s highest spatial resolution(250 m),was taken as the input *** auto-threshold function was also introduced into the change detection process to distinguish rice paddies from other *** MODIS-derived maps were validated with ground surveys and then compared with China national statistical data of rice paddy *** results indicated that the best classification result was achieved for plain regions,and that the accuracy declined for hilly regions,where the complex landscape could lead to an underestimation of the rice paddy area.A comparison between the modeled results and other analyses using 500-m MODIS data suggests that rice paddies may be identified routinely using a single vegetation index with finer resolution on large spatial scales.

关键词： HANTS algorithm moderate resolution imaging spectroradiometer(MODIS) land surface water index Otsu’s algorithm rice cultivation

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Natural Disaster Risk Monitoring for Immovable Cultural Relics Based on Digital Twin

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Journal of Geodesy and Geoinformation Science 2024年第1期7卷 90-104页

作者： li bolun DONG Youqiang QIAO Yunfei HOU Miaole WEN Caihuan The International Joint Laboratory of Safety and Energy Conservation for Ancient Buildings Beijing University of Civil Engineering and ArchitectureBeijing 102616China China Cultural Heritage Information and Consulting Center Beijing 100029China Hebei Institute of Geological Surveying and Mapping Langfang 065000China

Natural disaster risk monitoring is an important task for disaster prevention and *** the case of immovable cultural relics,however,the feedback mechanism,risk factors,monitoring logic,and monitoring indicators of natural disaster risk monitoring are *** to achieve intelligent perception and monitoring of natural disaster risk for immovable cultural relics has always been a focus and a challenge for *** on the analysis of the concepts and issues related to the natural disaster risk of immovable cultural relics,this paper proposes a framework for natural disaster risk monitoring for immovable cultural relics based on the digital *** framework focuses on risk monitoring,including the physical entities of natural disaster risk for immovable cultural relics,monitoring indicators,and virtual entity construction.A platform for monitoring the natural disaster risk of immovable cultural relics is *** the Puzhou Ancient City Site as a test bed,the proposed concept can be used for monitoring the natural disaster risk of immovable cultural relics at different scales.

关键词： immovable cultural relics natural disaster risk digital twin risk monitoring

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Development of a new index for automated mapping of ratoon rice areas using time-series normalized difference vegetation index imagery

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Pedosphere 2022年第4期32卷 576-587页

作者： bolun li Shaobing PENG Runping SHEN Zong-liang YANG Xiaoyuan YAN Xiaofeng li Rongrong li Chengye li Guangbin ZHANG School of Geographical Sciences Nanjing University of Information Science and TechnologyNanjing 210044China College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China Jackson School of Geosciences The University of Texas at AustinAustinUSA Institute of Soil Science Chinese Academy of SciencesNanjing 210008China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China

Over recent decades, the global demand for food has continued to grow, owing to population growth and the loss of arable land. Rice ratooning offers new opportunities for increasing rice production and has received renewed interest because of the minimal additional labor input required for its adoption. Regular, regional-scale monitoring of the spatial patterns of both traditional and ratoon rice cropping systems provides essential information for agricultural resource management and food security studies. However, the similar phenological characteristics of traditional double rice and ratoon rice cropping systems make it challenging to accurately classify these cropping practices based on satellite observations alone. In this study, we first proposed an improved phenology-based rice cropping area detection algorithm using moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) imagery. A new index, ratoon rice index, was then developed to automatically delineate ratoon rice cropping areas with the aid of a base map of rice in Hubei Province, China. The accuracy assessment using ground truth data showed that our approach could map both traditional and ratoon rice cropping areas with high user accuracy (91.25% and 91.43%, respectively). The MODIS-retrieved rice cropping areas were validated using annual agricultural census data, and coefficient of determination (R2) values of 0.60 and 0.41 were recorded for traditional and ratoon rice cropping systems, respectively. The total area of ratoon rice was estimated to be 1 283.6 km2, 5.0% of the total rice cropping area, in Hubei Province in 2016. These demonstrated the feasibility of extracting the spatial patterns of both traditional and ratoon rice cropping systems solely from time-series NDVI and field survey data and strides made in facilitating the timely and routine monitoring of traditional and ratoon rice distribution at subnational level. Given sufficient historical sat

关键词： cropping area estimationcross correlogram moderate resolution imaging spectroradiometer(MODIS) ratoon rice index spectral matching

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Suppression of Multi-Harmonic Currents in the High-Speed Magnetically Suspended Motor Based on Adaptive Cascaded Notch Filters with Variable Phase Angle

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Guidance, Navigation and Control 2024年第2期4卷 104-122页

作者： Xianzhang Wang Xiangbo Xu Shao Chen lingbo Zheng Junfeng li bolun li School of Technology Beijing Forestry University Beijing 100084 P.R.China

Rotor imbalance is identified as one of the predominant vibration sources in high-speed magnetically suspended *** to factors such as rotor machining accuracy errors and uneven material distribution,synchronous vibration interference is ***,sensor runout generates harmonic currents,which are attributed to material irregularities and inhomogeneity in the roundness of the sensor detection *** currents can generate harmonic vibrational forces that are transmitted to the motor housing,jeopardizing control accuracy and the device's operational *** order to achieve real-time reduction of harmonic currents at specified frequencies and improve the accuracy of harmonic suppression,this paper proposes an algorithm for variable phase anglefiltering of an adaptive cascaded mode *** paper performed dynamic modeling and analysis of the magnetically suspended rotor system with rotor imbalance and verified the correctness of the dynamic ***,the structure of an adaptive notchfilter with variable phase angle is introduced,highlighting the capability to maintain stability by adjusting the compensatory phase of the *** comparing the harmonic current suppression performance of cascaded and parallel mode notchfilters,the cascaded method can better enhance the overall frequency selectivity,emphasizing its ability to adjust the compensation phase based on the phase angle of the input signal at different frequencies to maintain system *** and experimental results show that harmonic currents can be successfully suppressed in the cascade mode,and the amplitude of the synchronous frequency current is reduced by 94.4%.

关键词： Multi-harmonic current suppression rotor imbalance sensor runout cascaded mode notchfilter variable phase angle

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Stability Conditions for Event-triggered Control Systems with limited Bandwidth and Network Delay

Stability Conditions for Event-triggered Control Systems wit...

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第30届中国控制与决策会议

作者： Qing Gao bolun li Rundong Dou Department of Enterprise Management and Information Technology Weichai Power Co. Ltd. School of Economics and Management Hebei University of Technology University of Science and Technology of China

This paper proposes a model-based event-triggered control strategy to reduce the occupation of network resources. We study the problems of the bounded network delay in event-triggered quantized feedback control *** order to avoid the Zeno behavior, an event-triggering condition is designed to ensure the asymptotic stability of the system and a lower bound of the stabilizing quantization bit rates is obtained. The updating strategy based on the time stamp is introduced, and the constraints on the network delay are given. Based on these conditions, an upper bound on the tolerable network delay is derived. Simulations are done to demonstrate the effectiveness of the control strategy proposed in this paper.

关键词： Quantized Feedback Control Event-Triggered Control Asymptotic Stability Network Delay

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肌层浸润性膀胱癌保留膀胱的综合治疗策略

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中南大学学报（医学版） 2018年第1期43卷 82-89页

作者：李博伦李源中南大学湘雅医院泌尿外科长沙410008

膀胱癌是泌尿系常见的恶性肿瘤,其中肌层浸润性膀胱癌的标准治疗方案是膀胱根治性切除术,但该手术对于患者自身及术后生活均会造成巨大的影响。对此,不少国内外学者指出部分合适的患者可以选择以保留膀胱的手术为主,同时辅以放射治疗、... 详细信息

膀胱癌是泌尿系常见的恶性肿瘤,其中肌层浸润性膀胱癌的标准治疗方案是膀胱根治性切除术,但该手术对于患者自身及术后生活均会造成巨大的影响。对此,不少国内外学者指出部分合适的患者可以选择以保留膀胱的手术为主,同时辅以放射治疗、化学治疗等辅助性治疗的综合治疗方案,术后对患者进行密切的随访,其疗效同根治性膀胱切除术相近,且手术风险及并发症的发生率也显著低于根治性膀胱切除术,而患者则可以保留有功能的膀胱。

关键词：肌层浸润性膀胱癌保留膀胱治疗三联治疗

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Endothelial phosphodiesterase 4B inactivation ameliorates endothelial-to-mesenchymal transition and pulmonary hypertension

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1726-1741页

作者： Yanjiang Xing Yangfeng Hou Tianfei Fan Ran Gao Xiaohang Feng bolun li Junling Pang Wenjun Guo Ting Shu Jinqiu li Jie Yang Qilong Mao Ya Luo Xianmei Qi Peiran Yang Chaoyang liang Hongmei Zhao Wenhui Chen Jing Wang Chen Wang State Key Laboratory of Respiratory Health and Multimorbidity Institute of Basic Medical SciencesChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100005China Department of Lung Transplantation National Center for Respiratory MedicineNational Clinical Research Center for Respiratory DiseasesChina–Japan Friendship HospitalInstitute of Respiratory MedicineChinese Academy of Medical SciencesBeijing 100029China Haihe Laboratory of Cell Ecosystem Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300051China The State Key Laboratory of Complex Severeand Rare DiseasesInstitute of Basic Medical SciencesChinese Academy of Medical SciencesDepartment of PathophysiologyPeking Union Medical CollegeBeijing 100005China Department of Pharmacy West China HospitalSichuan UniversityChengdu 610044China

Pulmonary hypertension (PH) is a fatal disorder characterized by pulmonary vascular remodeling and obstruction. The phosphodiesterase 4 (PDE4) family hydrolyzes cyclic AMP (cAMP) and is comprised of four subtypes (PDE4A–D). Previous studies have shown the beneficial effects of pan-PDE4 inhibitors in rodent PH;however, this class of drugs is associated with side effects owing to the broad inhibition of all four PDE4 isozymes. Here, we demonstrate that PDE4B is the predominant PDE isozyme in lungs and that it was upregulated in rodent and human PH lung tissues. We also confirmed that PDE4B is mainly expressed in the lung endothelial cells (ECs). Evaluation of PH in Pde4b wild type and knockout mice confirmed that Pde4b is important for the vascular remodeling associated with PH. In vivo EC lineage tracing demonstrated that Pde4b induces PH development by driving endothelial-to-mesenchymal transition (EndMT), and mechanistic studies showed that Pde4b regulates EndMT by antagonizing the cAMP-dependent PKA–CREB–BMPRII axis. Finally, treating PH rats with a PDE4B-specific inhibitor validated that PDE4B inhibition has a significant pharmacological effect in the alleviation of PH. Collectively, our findings indicate a critical role for PDE4B in EndMT and PH, prompting further studies of PDE4B-specific inhibitors as a therapeutic strategy for PH.

关键词： Phosphodiesterase 4B Pulmonary hypertension Endothelial-to-mesenchymal transition

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Gefitinib and fostamatinib target EGFR and SYK to attenuate silicosis:a multi-omics study with drug exploration

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Signal Transduction and Targeted Therapy 2022年第6期7卷 2066-2078页

作者： Mingyao Wang Zhe Zhang Jiangfeng liu Meiyue Song Tiantian Zhang Yiling Chen Huiyuan Hu Peiran Yang bolun li Xiaomin Song Junling Pang Yanjiang Xing Zhujie Cao Wenjun Guo Hao Yang Jing Wang Juntao Yang Chen Wang State Key Laboratory of Medical Molecular Biology Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100005China Laboratory of Stem Cell and Tissue Engineering Orthopedic Research InstituteState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengdu 610041China Department of Pulmonary and Critical Care Medicine The First Hospital of Shanxi Medical UniversityTaiyuan 030001China NHC Key Laboratory of Pneumoconiosis Taiyuan 030001China Shanxi Province Key Laboratory of Respiratory Disease Taiyuan 030001China Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship HospitalBeijing 100029China Department of Respiratory and Critical Care Medicine The First Affiliated Hospital of Xi’an Jiao tong UniversityXi’an 710061China Key Lab of Transplant Engineering and Immunology MOHRegenerative Medical Research CenterWest China HospitalSichuan UniversityChengdu 610041China

Silicosis is the most prevalent and fatal occupational disease with no effective therapeutics,and currently used drugs cannot reverse the disease *** still,there are still challenges to be addressed to fully decipher the intricated ***,specifying the essential mechanisms and targets in silicosis progression then exploring anti-silicosis pharmacuticals are desperately *** this work,multi-omics atlas was constructed to depict the pivotal abnormalities of silicosis and develop targeted *** utilizing an unbiased and time-resolved analysis of the transcriptome,proteome and phosphoproteome of a silicosis mouse model,we have verified the significant differences in transcript,protein,kinase activity and signaling pathway level during silicosis progression,in which the importance of essential biological processes such as macrophage activation,chemotaxis,immune cell recruitment and chronic inflammation were ***,the phosphorylation of EGFR(p-EGFR)and SYK(pSYK)were identified as potential therapeutic targets in the progression of *** inhibit and validate these targets,we tested fostamatinib(targeting SYK)and Gefitinib(targeting EGFR),and both drugs effectively ameliorated pulmonary dysfunction and inhibited the progression of inflammation and ***,our drug discovery with multi-omics approach provides novel and viable therapeutic strategies for the treatment of silicosis.

关键词： silicosis SYK drugs

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电液全可变气门工作周期的划分及特征时间与占比变化规律的研究

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机械工程学报 2017年第12期53卷 201-208页

作者：韩伟强李博仑潘锁柱李鑫西华大学流体及动力机械教育部重点实验室成都610039

电液全可变气门系统的精确控制直接影响其物理作用效果。通过采集该系统的四个信号(电磁阀阀前油压信号、油腔内油压信号、气门附加升程信号以及电磁阀驱动电流信号),分析信号特征位置间的时间差,将系统一个完整的工作周期划分成六个特... 详细信息

电液全可变气门系统的精确控制直接影响其物理作用效果。通过采集该系统的四个信号(电磁阀阀前油压信号、油腔内油压信号、气门附加升程信号以及电磁阀驱动电流信号),分析信号特征位置间的时间差,将系统一个完整的工作周期划分成六个特征阶段(电磁阀开启延迟、电磁阀安装位置延迟、气门惯性延迟、充油阶段、泄油阶段以及电磁阀关闭延迟)。加上总延迟与完整的工作周期,共得到8个特征时间。通过分析控制参数对不同特征时间时长与占比的影响规律,得到的结果如下:不同特征时间对控制参数变化的敏感性不同,且特征时间对控制参数变化不敏感时,其占比不一定能忽略。减小系统总延迟、优化系统的控制参数、减小附加升程都有助于缩短系统工作总周期,提高系统的响应速度。研究为系统的精确控制与系统优化提供了理论与试验基础。

关键词：柴油机电液全可变气门工作周期划分特征时间占比

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基于CP-ABE和区块链的时间锁加密电子投票方案

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计算机应用研究 2023年第11期40卷 3408-3415,3424页

作者：沈华李博轮湖北工业大学计算机学院武汉430068 桂林电子科技大学广西可信软件重点实验室广西桂林541004

现有电子投票系统无法同时满足投票数据隐私性、投票者之间的公平性、投票者资格控制的灵活性、投票结果的精准性、投票结果的延时公布等多元应用需求。针对上述问题,提出了一种基于CP-ABE和区块链的时间锁加密电子投票方案。该方案综... 详细信息

现有电子投票系统无法同时满足投票数据隐私性、投票者之间的公平性、投票者资格控制的灵活性、投票结果的精准性、投票结果的延时公布等多元应用需求。针对上述问题,提出了一种基于CP-ABE和区块链的时间锁加密电子投票方案。该方案综合考虑了电子投票在实际场景中的多元应用需求,通过结合CP-ABE算法和Fabric技术,将属性加密后的投票链接数据存入区块链账本,满足属性策略的投票用户才能访问其链接,实现了灵活控制投票资格的机制,从而保证能获取针对不同用户群体属性的精确投票结果;基于改进的时间锁加密方案将投票数据进行加密上链,在预计投票结果公布之前为投票数据的机密性提供了保障,避免恶意节点造成合谋攻击问题,同时实现了投票结果延时公布的功能。实验从用户属性限制、投票链接获取、投票数据上链,以及投票结果延时这四个方面验证所提方案的有效性。系统测试结果表明,该方案可以有效地控制投票资格,符合属性策略的投票用户能成功获取投票链接并发送至区块链存储,同时为投票数据的机密性提供了保障。通过性能分析、安全性分析以及对比分析表明了该方案的可行性。

关键词：区块链电子投票时间锁加密 Fabric

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