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农业工程学报 2006年第2期22卷 1-5页

作者：董乔雪王一鸣 jean francois barczi 贺超兴中国农业大学(东校区)信息与电气工程学院北京100083 中国科学院自动化研究所中法联合实验室LIAMA 北京100080 中国农业科学院蔬菜花卉研究所北京100081

对番茄生长模型参数进行准确估算是模型得以验证和面向应用的前提条件。基于番茄拓扑结构,采用非线性最小二乘优化方法,通过对植株形态数据的多目标拟合,实现模型参数的最优估计和校准。非线性最小二乘法的权值根据目标数据自动调整,使... 详细信息

对番茄生长模型参数进行准确估算是模型得以验证和面向应用的前提条件。基于番茄拓扑结构,采用非线性最小二乘优化方法,通过对植株形态数据的多目标拟合,实现模型参数的最优估计和校准。非线性最小二乘法的权值根据目标数据自动调整,使得不同量纲和不同数值范围的观测数据可以在同一水平上进行,提高了计算的精度和稳定性;另一方面用差商近似代替导数加快了算法的收敛速度。通过应用拟合优度检验,得出模型输出对观测值的拟合程度较好,说明模型合理,参数可靠。实践表明该估算方法是对模型进行验证的一个行之有效的方法。

关键词：番茄模型参数估算多目标拟合非线性最小二乘方法

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不同光截获下番茄形态结构的动态模拟与比较

中国农业大学学报 2005年第5期10卷 26-31页

作者：董乔雪王一鸣 jean francois barczi 贺超兴中国农业大学信息与电气工程学院北京100083 中国科学院自动化研究所中法联合实验室北京100080 中国农业科学院蔬菜花卉研究所北京100081

为研究不同光截获对番茄植株形态结构的影响,基于结构-功能互反馈建模原理建立了番茄结构-功能模型。采用基于番茄拓扑结构的多目标估算方法,利用实验观测数据对模型进行多目标校准和验证。对局部遮阴和无遮阴栽培条件下番茄植株的生长... 详细信息

为研究不同光截获对番茄植株形态结构的影响,基于结构-功能互反馈建模原理建立了番茄结构-功能模型。采用基于番茄拓扑结构的多目标估算方法,利用实验观测数据对模型进行多目标校准和验证。对局部遮阴和无遮阴栽培条件下番茄植株的生长过程进行动态模拟,并对不同生长阶段番茄植株的形态结构、器官周期累积生物量以及器官三维形态输出进行比较,结果表明:无遮阴栽培条件下,番茄植株茎杆节间短粗,叶片和果实较大,而局部遮阴栽培条件下番茄植株茎杆细长,叶片稀薄,果实较小。不同光截获下模型的输出结果与观测数据拟合较好,验证了模型的有效性。

关键词：番茄形态结构结构-功能模型无遮阴栽培局部遮阴栽培

番茄的结构-功能模型Ⅰ:基于有限态自动机的3D形态构建

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中国生态农业学报 2006年第4期14卷 195-199页

作者：董乔雪王一鸣 jean francois barczi 中国农业大学(东校区)信息与电气工程学院北京100083 中国科学院自动化研究所中法联合实验室LIAMA 北京100080

根据番茄的形态结构特点及其演变规则,应用有限态自动机的数学理论,研究建立了番茄动态发展的随机结构模型。该模型建立在对番茄结构的宏观抽象和生理年龄(PHYAGE)与生长年龄(GA)这两个最重要的基本概念之上,利用“事件驱动”的状态转... 详细信息

根据番茄的形态结构特点及其演变规则,应用有限态自动机的数学理论,研究建立了番茄动态发展的随机结构模型。该模型建立在对番茄结构的宏观抽象和生理年龄(PHYAGE)与生长年龄(GA)这两个最重要的基本概念之上,利用“事件驱动”的状态转移机制模拟了番茄生长过程、分枝过程和死亡过程,其中利用了二项随机分布模拟番茄的动态生长,离散的Markov链用于模拟番茄的分枝模式。番茄的有限态自动机模型完成了对主茎上节间长度、果实个数以及叶子结构的随机模拟。并利用试验统计分析获得的参数结果,模拟出番茄在不同生长阶段的3D结构。该动态的番茄结构模型,为与生理生态模型进行接口建立互影响、互反馈的结构-功能模型打下了基础。

关键词：番茄结构模型有限态自动机随机分布

番茄的结构-功能模型Ⅱ:基于器官水平的功能模型与验证研究

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中国生态农业学报 2007年第1期15卷 122-126页

作者：董乔雪王一鸣 jean francois barczi 侯加林中国农业大学信息与电气工程学院北京100083 中国科学院自动化研究所中法联合实验室北京100080

建立了番茄动态生长的功能模型,从个体和器官的角度,研究生物量在植物体内的生产和分配规律、器官的动态生长规则。模型根据蒸腾作用计算物质的生产;根据节间、叶柄、叶片和果实等器官的汇强和扩展规律对物质进行分配;根据与物质量的动... 详细信息

建立了番茄动态生长的功能模型,从个体和器官的角度,研究生物量在植物体内的生产和分配规律、器官的动态生长规则。模型根据蒸腾作用计算物质的生产;根据节间、叶柄、叶片和果实等器官的汇强和扩展规律对物质进行分配;根据与物质量的动态关系计算各器官的几何尺寸;利用试验数据对模型参数进行估计。通过对参数进行比较和分析得出它们对各器官生长的影响程度和器官本身的扩展规律。并对模型输出与测量数据的拟合程度进行了残差分析,验证了模型的合理性和有效性。

关键词：番茄器官结构-功能模型生产和分配扩展规律

Design and Experimental Testing of a Moving Coil Actuator with Compensation Coil

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 707-716页

作者： Boyuan Yin Xianwu Zeng John Frederick Eastham Emelie Nilsson jean-francois Rouquette jean Rivenc Ludovic Ybanez Xiaoze Pei Department of Electronics&Electrical Engineering University of BathBathBA27AYUnited Kingdom Airbus UpNext BlangnacFrance Airbus CRT BlangnacFrance Department of Mechanical Engineering University of BathBathBA27AYUnited Kingdom

Hydrogen-powered electric aircraft have attracted significant interests aiming to achieve decarbonization *** DC electric networks are facing great challenges in DC fault protection *** interrupters are widely used in low voltage and medium voltage power systems due to being environmentally friendly with low *** this paper a moving coil actuator with compensation coils for a vacuum interrupter,as part of a hybrid direct current circuit breaker,is designed and experimentally *** coils are used to improve operating speed compared with original moving coil *** between four possible connections of compensation coils and original moving coil actuator are carried *** results show comparisons between different connections of actuator coils in terms of opening time and coil current with a range of pre-charged capacitor *** performance of each actuator connection is also *** actuator with compensation coils is shown to have a higher current rising rate and achieve faster opening speed,which is a critical requirement for electric aircraft network *** parallel connection actuator achieves the highest opening speed within 3.5 ms with capacitor voltage of 50 V.

关键词： Circuit breaker compensation coil moving coil actuator vacuum interrupter

From Control Theory to Gravitational Waves

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Advances in Pure Mathematics 2024年第2期14卷 49-100页

作者： jean-francois Pommaret CERMICS Ecole des Ponts Paris Tech Paris France

When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D1:η→ξ such that Dξ = η implies D1η = 0. When D is involutive, the procedure provides successive first-order involutive operators D1,...,Dn when the ground manifold has dimension n. Conversely, when D1 is given, a much more difficult “inverse problem” is to look for an operator D:ξ→η having the generating CC D1η = 0. If this is possible, that is when the differential module defined by D1 is “torsion-free”, that is when there does not exist any observable quantity which is a sum of derivatives of η that could be a solution of an autonomous OD or PD equation for itself, one shall say that the operator D1 is parametrized by D. The parametrization is said to be “minimum” if the differential module defined by D does not contain a free differential submodule. The systematic use of the adjoint of a differential operator provides a constructive test with five steps using double differential duality. We prove and illustrate through many explicit examples the fact that a control system is controllable if and only if it can be parametrized. Accordingly, the controllability of any OD or PD control system is a “built in” property not depending on the choice of the input and output variables among the system variables. In the OD case and when D1 is formally surjective, controllability just amounts to the formal injectivity of ad(D1), even in the variable coefficients case, a result still not acknowledged by the control community. Among other applications, the parametrization of the Cauchy stress operator in arbitrary dimension n has attracted many famous scientists (G. B. Airy in 1863 for n = 2, J. C. Maxwell in 1870, E. Beltrami in 1892 for n = 3, and A. Einstein in 1915 for n = 4).

关键词： Differential Operator Differential Sequence Killing Operator Riemann Operator Bianchi Operator Cauchy Operator Control Theory Controllability Elasticity General Relativity

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构建安全连接,筑牢通信行业高质量发展底座

数字经济 2024年第4期 93-95页

作者： jean-francois Ouillet 泰雷兹集团

身处数字化时代,以新一代信息通信技术为核心的物联网(IoT)正在重塑各行各业,为数字经济发展注入强劲动力;同时,也在改变着每个人与周围世界互动的方式,为日常生活带来更多便捷选择。物联网不断为行业数字化转型提供新支撑、为数字经济... 详细信息

身处数字化时代,以新一代信息通信技术为核心的物联网(IoT)正在重塑各行各业,为数字经济发展注入强劲动力;同时,也在改变着每个人与周围世界互动的方式,为日常生活带来更多便捷选择。物联网不断为行业数字化转型提供新支撑、为数字经济发展拓展新空间,整个市场也在持续探索更灵活便捷、安全可靠的连接方式,以应对新挑战。

关键词：信息通信技术通信行业数字化转型数字化时代安全连接强劲动力灵活便捷连接方式

21世纪全球新建水库编目:丰度、热点区及总蓄水量

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Science Bulletin 2024年第14期69卷 2179-2182页

作者：范晨雨宋春桥 Jida Wang Yongwei Sheng 蔺亚玲苑春雨 Md Safat Sikder jean-francois Crétaux 刘凯陈探曾繁轩柯灵红 Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China University of Chinese Academy of Sciences Nanjing(UCASNJ)Nanjing 211135China Department of Geography and Geographic Information Science University of Illinois Urbana-ChampaignUrbana IL 61801USA Department of Geography and Geospatial Sciences Kansas State UniversityManhattan KS 66506USA Department of Geography University of CaliforniaLos Angeles CA 90095USA Laboratoire d’Études en Géophysique et Océanographie Spatiales(LEGOS) CNES-IRD-CNRS-UT3Universitéde ToulouseToulouse 31401France College of Hydrology and Water Resources Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China

Dams and reservoirs play an essential role in regulating and managing water *** the middle of the 20th century,the growing demand for water and hydropower has led to an unprecedented boom in reservoir construction worldwide[1,2].Meanwhile,reservoir construction has also resulted in a variety of ecological and socioeconomic impacts[3–5].Reservoirs transform natural flow regimes into conditions favored by human *** associated flow regulations,especially in reservoirs constructed in recent decades(e.g.,after 2000)with greater seasonal variability[6,7],represent a strong human-induced alteration of the hydrologic *** reservoir construction continues to boom in many parts of the world,an up-to-date and openaccess inventory of reservoirs worldwide remains critically desired.

关键词： reservoir reservoirs alteration

Application of near-infrared spectroscopy for fast germplasm analysis and classification in multi-environment using intact-seed peanut(Arachis hypogaea L.)

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Oil Crop Science 2024年第2期9卷 132-141页

作者： Fentanesh Chekole Kassie Gilles Chaix Hermine Bille Ngalle Maguette Seye Coura Fall Hodo-Abalo Tossim Aissatou Sambou Olivier Gibert Fabrice Davrieux Joseph Martin Bell jean-francois Rami Daniel Fonceka Joel Romaric Nguepjop Department of Plant Biology and Physiology Faculty of SciencesUniversity of Yaounde IYaoundeP.O.Box 337Cameroon Department of Plant Science College of AgricultureWolaita Sodo UniversitySodoP.O.Box 138Ethiopia CIRAD UMR AGAP InstitutMontpellierFrance AGAP Institut Univ MontpellierCIRADINRAEInstitut AgroMontpellierFrance ChemHouse Research Group MontpellierFrance Centre D’Etudes Regional Pour L’Amelioration de L’Adaptation a La Secheresse(CERAAS/ISRA) Route de KhomboleThiesBP 3320Senegal Dispositif de Recherche et de Formation en Partenariat Innovation et Amelioration Varietale en Afrique de L’Ouest(IAVAO)CERAASRoute de KhomboleThiesBP 3320Senegal CIRAD UMR QUALISUDSaint PierreFrance

Peanut is a worldwide oilseed crop and the need to assess germplasm in a non-destructive manner is important for seed nutritional *** this study,Near Infrared Spectroscopy(NIRS)was applied to rapidly assess germplasm variability from whole seed of 699 samples,field-collected and assembled in four genetic and environmentbased sets:one set of 300 varieties of a core-collection and three sets of 133 genotypes of an interspecific population,evaluated in three environments in a large spatial scale of two countries,Mbalmayo and Bafia in Cameroon and Nioro in Senegal,under rainfed *** elemental spectra were gathered on six subsets of seeds of each sample,after three rotation scans,with a spectral resolution of 16 cm-1over the spectral range of867 nm to 2530 *** were then processed by principal component analysis(PCA)coupled with Partial least squares-discriminant analysis(PLS-DA).As results,a huge variability was found between varieties and genotypes for all NIR wavelength within and between *** magnitude of genetic variation was particularly observed at 11 relevant wavelengths such as 1723 nm,usually related to oil content and fatty acid *** yielded the most chemical attributes in three significant PCs(i.e.,eigenvalues>10),which together captured 93%of the total variation,revealing genetic and environment structure of varieties and genotypes into four clusters,corresponding to the four samples *** pattern of genetic variability of the interspecific population covers,remarkably half of spectrum of the core-collection,turning out to be the ***,a PLS-DA model was developed and a strong accuracy of 99.6%was achieved for the four sets,aiming to classify each seed sample according to environment *** confusion matrix achieved for the two sets of Bafia and Nioro showed 100%of instances classified correctly with 100%at both sensitivity and specificity,confirming that their seed quality was different f

关键词： Groundnut Oilseed Near infrared spectroscopy Germplasm analysis Environment Nutritional Breeding