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Leaf pigment retrieval using the PROSAIL model: Influence of uncertainty in prior canopy-structure information

The Crop Journal 2022年第5期10卷 1251-1263页

作者： Jia Sun Lunche Wang Shuo Shi zhenhai li Jian Yang Wei Gong Shaoqiang Wang Torbern Tagesson Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeoscienceWuhan 430079HubeiChina Department of Physical Geography and Ecosystem Science Lund UniversityLund 117 SE-22100Sweden State Key Laboratory of Information Engineering in Surveying Mappingand Remote SensingWuhan UniversityWuhan 430079HubeiChina Key Laboratory of Quantitative Remote Sensing in Ministry of Agriculture and Rural Affairs Beijing Research Center for Information Technology in AgricultureBeijing 100097China Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagen 1172Denmark

Leaf pigments are critical indicators of plant photosynthesis,stress,and physiological *** of radiative transfer models(RTMs)is a promising method for robustly retrieving leaf biochem-ical traits from canopy observations,and adding prior information has been effective in alleviating the“ill-posed”problem,a major challenge in model *** structure parameters,such as leaf area index(LAI)and average leaf inclination angle(ALA),can serve as prior information for leaf pigment *** canopy spectra simulated from the PROSAIL model,we estimated the effects of uncertainty in LAI and ALA used as prior information for lookup table-based inversions of leaf chlorophyll(C _(ab))and car-otenoid(C_(ar)).The retrieval accuracies of the two pigments were increased by use of the priors of LAI(RMSE of C_(ab) from 7.67 to 6.32μg cm^(-2),C_(ar) from 2.41 to 2.28μg cm^(-2))and ALA(RMSE of C_(ab) from 7.67 to 5.72μg cm^(-2),C_(ar) from 2.41 to 2.23μg cm^(-2)).However,this improvement deteriorated with an increase of additive and multiplicative uncertainties,and when 40% and 20% noise was added to LAI and ALA respectively,these priors ceased to increase retrieval *** using an experimental winter wheat dataset also showed that compared with C_(ar),the estimation accuracy of C_(ab) increased more or deteriorated less with uncertainty in prior canopy *** study demonstrates possible limita-tions of using prior information in RTM inversions for retrieval of leaf biochemistry,when large uncer-tainties are present.

关键词： Leaf pigment PROSAIL model Canopy structure Chlorophyll content Leaf area index Leaf angle distribution

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微创经皮钢板内固定技术在锁骨中段粉碎性骨折锁定钢板固定术中应用

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临床误诊误治 2024年第3期37卷 94-98页

作者：唐德胜王晓亚刘西斌康永浩李振海黄骅市人民医院骨科河北黄骅061100

目的探讨微创经皮钢板内固定(MIPPO)技术在锁骨中段粉碎性骨折锁定钢板固定术中的应用价值。方法回顾性选取2020年6月—2022年6月130例锁骨中段粉碎性骨折的临床资料,根据手术方法分为观察组和对照组,每组65例。对照组行传统切开复位... 详细信息

目的探讨微创经皮钢板内固定(MIPPO)技术在锁骨中段粉碎性骨折锁定钢板固定术中的应用价值。方法回顾性选取2020年6月—2022年6月130例锁骨中段粉碎性骨折的临床资料,根据手术方法分为观察组和对照组,每组65例。对照组行传统切开复位内固定,观察组行MIPPO技术联合锁定钢板治疗。比较2组围术期指标、并发症、手术优良率及手术前后疼痛应激介质、肩关节功能指标。结果观察组切口长度、骨折愈合时间短于对照组,术中出血量少于对照组,术后1 d疼痛视觉模拟评分法评分低于对照组(P<0.01)。术后1 d,观察组血清P物质、前列腺素E_(2)低于对照组,β内啡肽高于对照组(P<0.05);术后3、6个月,观察组Constant-Murley肩关节功能评分及肩关节前屈、后伸、外旋活动度高于对照组(P<0.05)。观察组并发症总发生率低于对照组,术后6个月手术优良率高于对照组(P<0.05)。结论 MIPPO技术联合锁定钢板治疗锁骨中段粉碎性骨折能显著提高手术优良率,减少术中出血量,促进肩关节功能恢复,抑制疼痛因子释放,缓解术后早期疼痛,还能降低并发症风险。

关键词：锁骨粉碎性骨折锁定钢板微创经皮钢板内固定肩关节功能 P物质前列腺素E_(2) 疼痛并发症

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油气管道高速总线信号质量检测技术研究

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中国仪器仪表 2024年第9期 34-38页

作者：黄忠胜吕志勇王昊李振海张晓玲国家管网集团西部管道责任有限公司新疆乌鲁木齐830013 北京东土科技股份有限公司北京100144 沈阳工业大学辽宁沈阳110870

油气管道高速总线核心技术中采用无线通信中已经成熟应用的OFDM技术,实现了多节点,长距离,高带宽和实时传输特性。通过对频带和时隙资源的有效利用,保证信号质量稳定的实时传输数据。相对于传统现场总线和以太网总线技术,带宽更高、传... 详细信息

油气管道高速总线核心技术中采用无线通信中已经成熟应用的OFDM技术,实现了多节点,长距离,高带宽和实时传输特性。通过对频带和时隙资源的有效利用,保证信号质量稳定的实时传输数据。相对于传统现场总线和以太网总线技术,带宽更高、传输速率更大。针对实际生产应用过程中信号质量检测的问题,本文根据上行还是下行链路方向,提出了两种信号质量检测方法。同时介绍了PHB总线网络信号质量检测技术的实现原理,并提出对PHB总线网络的信号质量好坏的评判标准,为运行维护PHB总线过程中监控信号质量,排查网络问题,以及为各仪表设备厂商、线缆和连接器厂商等开发适合PHB总线的终端设备调试时提供了一种可靠的测量信号质量的方法。

关键词： PHB 现场总线信号质量检测

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全热交换芯体在非国标乃至极端工况下的性能研究

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建筑科技 2024年第3期8卷 44-50页

作者：常远李振海车闫瑾裘舒年张盛世辛电波同济大学机械与能源工程学院上海201804 青岛海信日立空调系统有限公司山东青岛266071 浙江科技大学土木与建筑工程学院浙江杭州310023

为探索非国标乃至极端工况下各种影响因素对全热交换芯体性能的影响特点,使用非对称式高分子基膜材制作了2个不同规格的正方形全热交换芯体,在焓差实验室中进行性能测试。采用控制变量法进行分组分析,详细探究室外干球温度、室外相对湿... 详细信息

为探索非国标乃至极端工况下各种影响因素对全热交换芯体性能的影响特点,使用非对称式高分子基膜材制作了2个不同规格的正方形全热交换芯体,在焓差实验室中进行性能测试。采用控制变量法进行分组分析,详细探究室外干球温度、室外相对湿度等自变量在非国标数值甚至极端数值时,对芯体显热效率、潜热效率以及焓效率的影响。结果表明:室外干球温度仅对芯体冬季潜热效率有明显影响;夏季室外相对湿度较低时,芯体的潜热效率和焓效率相较于标准工况明显升高,冬季室外相对湿度升高,芯体潜热效率下降;回南天、梅雨天工况下,显热效率较标准工况有所下降,潜热效率显著下降,焓效率受空气温湿度影响波动较大;冬季严寒工况下,芯体的显热效率、潜热效率以及焓效率均基本稳定。

关键词：全热交换器新风热回收传热传质焓效率

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Deep neural network algorithm for estimating maize biomass based on simulated Sentinel 2A vegetation indices and leaf area index

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The Crop Journal 2020年第1期8卷 87-97页

作者： Xiuliang Jin zhenhai li Haikuan Feng Zhibin Ren Shaokun li Institute of Crop Sciences Chinese Academy of Agricultural SciencesKey Laboratory of Crop Physiology and EcologyMinistry of AgricultureBeijing 100081China Beijing Research Center for Information Technology in Agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102JilinChina

Accurate estimation of biomass is necessary for evaluating crop growth and predicting crop *** is also a key trait in increasing grain yield by crop *** aims of this study were(i)to identify the best vegetation indices for estimating maize biomass,(ii)to investigate the relationship between biomass and leaf area index(LAI)at several growth stages,and(iii)to evaluate a biomass model using measured vegetation indices or simulated vegetation indices of Sentinel 2A and LAI using a deep neural network(DNN)*** results showed that biomass was associated with all vegetation *** three-band water index(TBWI)was the best vegetation index for estimating biomass and the corresponding R2,RMSE,and RRMSE were 0.76,2.84 t ha−1,and 38.22%*** was highly correlated with biomass(R2=0.89,RMSE=2.27 t ha−1,and RRMSE=30.55%).Estimated biomass based on 15 hyperspectral vegetation indices was in a high agreement with measured biomass using the DNN algorithm(R2=0.83,RMSE=1.96 t ha−1,and RRMSE=26.43%).Biomass estimation accuracy was further increased when LAI was combined with the 15 vegetation indices(R2=0.91,RMSE=1.49 t ha−1,and RRMSE=20.05%).Relationships between the hyperspectral vegetation indices and biomass differed from relationships between simulated Sentinel 2A vegetation indices and *** estimation from the hyperspectral vegetation indices was more accurate than that from the simulated Sentinel 2A vegetation indices(R2=0.87,RMSE=1.84 t ha−1,and RRMSE=24.76%).The DNN algorithm was effective in improving the estimation accuracy of *** provides a guideline for estimating biomass of maize using remote sensing technology and the DNN algorithm in this region.

关键词： Biomass estimation Maize Vegetation indices Deep neural network algorithm LAI

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The Kinetics for Electrochemical Removal of Ammonia in Coking Wastewater

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Chinese Journal of Chemical Engineering 2011年第4期19卷 570-574页

作者： liANG zhenhai li Su GUO Wenqian FAN Caimei College of Chemistry and Chemical Engineering Taiyuan University of Technology Taiyuan 030024 China

Electrochemical removal of ammonia is a new and effective method in coking *** reaction mechanism of ammonia removal was proved by stable polarization curve in this ***,the supposing of reaction steps of the electrode were *** then reaction parameter of the electrode was measured by Tafel ***,the reaction mechanism was determined by quasi-equilibrium *** results showed that Cl2+H2O→HOCl+H++Cl was the rate-determining step,the calculated apparent transfer coefficient was uniform to the experimental value.

关键词：氨氮去除焦化废水电化学动力学极化曲线电极反应化学去除反应机理反应步骤

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siRNA药物在肿瘤靶向治疗中的研究进展

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药学进展 2024年第7期48卷 548-560页

作者：张从一牧原李振海王欣月蔡文秋刘晓婧邹倩李梦玮中国药科大学生命科学与技术学院江苏南京210009

小干扰RNA(siRNA)是一种新型核酸药物,其通过RNA干扰(RNAi)机制,在转录后水平靶向沉默靶基因的表达,从而发挥治疗疾病的作用。siRNA作为一种精准、特异、高效的基因沉默疗法,在肿瘤靶向治疗领域备受瞩目。目前,已有多款抗肿瘤siRNA疗法... 详细信息

小干扰RNA(siRNA)是一种新型核酸药物,其通过RNA干扰(RNAi)机制,在转录后水平靶向沉默靶基因的表达,从而发挥治疗疾病的作用。siRNA作为一种精准、特异、高效的基因沉默疗法,在肿瘤靶向治疗领域备受瞩目。目前,已有多款抗肿瘤siRNA疗法进入临床试验阶段。综述了近年来siRNA在肿瘤靶向治疗中的研究进展,包括siRNA作用机制、抗肿瘤siRNA药物研发近况,以及siRNA药物体内递送的优化策略,旨在为抗肿瘤siRNA药物的研发与临床应用提供新思路。

关键词： RNA干扰小干扰RNA 肿瘤靶向治疗肝外靶向纳米载体

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Modeling of Earth’s Gravity Fields Visualization Based on Quad Tree

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Geo-Spatial Information Science 2010年第3期13卷 216-220页

作者： LUO Zhicai li zhenhai ZHONG Bo School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China Key Laboratory of Geospace Enviromnent and Geodesy Ministry of Education 129 Luoyu Road Wuhan 430079 China

The problems of the earth's gravity fields' visualization are both focus and puzzle currently. Aiming at multiresolution rendering, modeling of the Earth's gravity fields' data is discussed in the paper by using LOD algorithm based on Quad Tree. First, this paper employed the method of LOD based on Quad Tree to divide up the regional gravity anomaly data, introduced the combined node evaluation system that was composed of viewpoint related and roughness related systems, and then eliminated the T-cracks that appeared among the gravity anomaly data grids with different resolutions. The test results demonstrated that the gravity anomaly data grids' rendering effects were living, and the computational power was low. Therefore, the proposed algorithm was a suitable method for modeling the gravity anomaly data and has potential applications in visualization of the earth's gravity fields.

关键词： LOD Quad Tree earth’s gravity fields multiresolution rendering

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脂肪酶固定化常用载体及方法的研究进展

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工业微生物 2024年第2期54卷 110-123页

作者：陈莉莉张建国丛文杰周化岚王明轩李振海王继国上海理工大学健康科学与工程学院食品科学与工程研究所上海200093 天筛(上海)科技有限公司上海200439

脂肪酶被广泛应用于生物传感器、精细化工和生物催化等诸多领域,在此情形下脂肪酶固定化是提高其重复利用率和催化效率的重要手段。文章按照微生物属、海洋属、动植物属的分类,分别介绍了脂肪酶的不同来源,重点总结了金属有机框架、介... 详细信息

脂肪酶被广泛应用于生物传感器、精细化工和生物催化等诸多领域,在此情形下脂肪酶固定化是提高其重复利用率和催化效率的重要手段。文章按照微生物属、海洋属、动植物属的分类,分别介绍了脂肪酶的不同来源,重点总结了金属有机框架、介孔氧化硅和凝胶等常用的新型酶固定化载体,并讨论了吸附法、共价交联法、包埋法、复合法等脂肪酶固定化常用方法的优缺点,以期为后续研究提供理论依据和参考。

关键词：脂肪酶固定化金属有机框架介孔氧化硅凝胶

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Remaining oil distribution characteristics in an oil reservoir with ultra-high water-cut

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Energy Geoscience 2024年第1期5卷 219-223页

作者： Hongmin Yu Youqi Wang li Zhang Qingxin Zhang zhenhai Guo Benzhe Wang Tao Sun SINOPEC Petroleum Exploration and Development Research Institute Beijing100083China Shengli Oil Production Plant SINOPEC Shengli Oilfield BranchDongyingShandong257051China

An accurate mapping and understanding of remaining oil distribution is very important for water control and stabilize oil production of mature oilfields in ultra-high water-cut ***,the Tuo-21 Fault Block of the Shengtuo Oilfield has entered the stage of ultra-high water cut(97.2%).Poor adaptability of the well pattern,ineffective water injection cycle and low efficiency of engineering measures(such as workover,re-perforation and utilization of high-capacity pumps)are the significant problems in the ultra-high water-cut *** order to accurately describe the oil and water flow characteristics,relative permeability curves at high water injection multiple(injected pore volume)and a semiquantitative method is applied to perform fine reservoir simulation of the Sand group 3e7 in the *** accurate reservoir model is built and history matching is *** distribution characteristics of remaining oil in lateral and vertical directions are quantitatively simulated and *** results show that the numerical simulation considering relative permeability at high injection multiple can reflect truly the remaining oil distribution characteristics after water flooding in an ultrahigh water-cut *** distribution of remaining oil saturation can be mapped more accurately and quantitatively by using the‘four-points and five-types’classification method,providing a basis for potential tapping of various remaining oil types of oil reservoirs in late-stage of development with high water-cut.

关键词： Ultra-high water-cut High water injection multiple Four-points and five-types Numerical simulation Remaining oil distribution

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