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Prediction Model of Kinetic Energy Conversion of Tandem Dual-Oscillator Based on Flow-Induced Vibration Experiment

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China Ocean Engineering 2022年第5期36卷 707-719页

作者： BAI Xu sun meng HAN Chuan-yu sun Hai School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Marine Renewable Energy Laboratory Department of Naval Architecture&Marine EngineeringUniversity of MichiganAnn Arbor MI 48109-2145USA College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

Flow-induced vibration energy harvesting devices typically use an elastically supported body immersed in an oncoming flow to convert the sea and river current's hydrokinetic energy into electrical *** proportion of energy the device collects is greatly influenced by parameters such as the water flow velocity,spacing between device components,structure size,and damping *** parameter optimization and performance predictions of flow-induced vibration energy harvesting devices,we train a model of the power harvesting efficiency under different damping ratios,stiffnesses,spacing ratios,and reduced velocities based on experimental *** improve the prediction accuracy,a feedforward network structure is optimized by using the topological evolutionary algorithm and a radial basis function *** analysis reveals that the radial basis function network model provides the best agreement with the experimental results and realizes accurate predictions of the power harvested by a dual-oscillator system in the vortex-induced vibration,transition region,and *** prediction results show that the model's maximum power harvesting efficiency occurs in the vortex-induced *** efficiency increases and then decreases with increasing stiffness and reduced velocity in this phase;an increase in the spacing ratio causes the effi-ciency to decrease and then increase;finally,increasing the damping ratio enhances the *** device achieves maximum power harvesting efficiency at a reduced velocity of U_(r)=*** proposed model effectively predicts the maximum efficiency and the corresponding damping ratio and stiffness of the vortex-induced vibration and galloping,providing a new method for predicting tandem dual-oscillator hydrodynamic power conversion in flow-induced vibration.

关键词： flow-induced vibration tandem double-oscillator radial basis function prediction

A Metadata Reconstruction Algorithm Based on Heterogeneous Sensor Data for Marine Observations

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Journal of Ocean University of China 2023年第6期22卷 1541-1550页

作者： GUO Shuai sun meng MAO Xiaodong College of Science Qingdao University of TechnologyQingdao 266520China College of Information and Control Engineering Qingdao University of TechnologyQingdao 266520China

Vast amounts of heterogeneous data on marine observations have been accumulated due to the rapid development of ocean observation *** state-of-art methods are proposed to manage the emerging Internet of Things(IoT)sensor ***,the use of an inefficient data management strategy during the data storage process can lead to missing metadata;thus,part of the sensor data cannot be indexed and utilized(i.e.,‘data swamp’).Researchers have focused on optimizing storage procedures to prevent such disasters,but few have attempted to restore the missing *** this study,we propose an AI-based algorithm to reconstruct the metadata of heterogeneous marine data in data swamps to solve the above ***,a MapReduce algorithm is proposed to preprocess raw marine data and extract its feature tensors in ***,load the feature tensors are loaded into a machine learning algorithm and clustering operation is *** similarities between the incoming data and the trained clustering results in terms of clustering results are also ***,metadata reconstruction is performed based on existing marine observa-tion data processing *** experiments are designed using existing datasets obtained from ocean observing systems,thus verifying the effectiveness of the *** results demonstrate the excellent performance of our proposed algorithm for the metadata recon-struction of heterogenous marine observation data.

关键词： Internet of Things(IoT) sensor data data swamp metadata reconstruction

Pollen tube,a one-way special train for special passengers

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Science Bulletin 2017年第17期62卷 1165-1166页

作者： Xiongpo Peng meng-Xiang sun College of Life Science Wuhan UniversityWuhan 430072China

Double fertilization is a specific characteristic of angiosperms,in which two sperm cells fuse with the egg and central cell respectively[1].Different from that of animals,the two sperm cells of angiosperms have lost their ***,to fulfill the double fertilization,the two immobile sperm cells have to be sent to the female games by a specific structure,the pollen *** landing on the stigma of the pistil,the pollen grain germinates and devel-

关键词：列车单向花粉管伸长精子细胞旅客中央细胞被子植物卵细胞

Gamete Recognition in Higher Plants:An Abstruse but Charming Mystery

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Journal of Integrative Plant Biology 2008年第7期50卷 868-874页

作者： Xiong-Bo Peng meng-Xiang sun Key Laboratory of Ministry of Education for Plant Developmental Biology College of Life Sciences Wuhan University Wuhan 430072 China

Although much effort has been made to uncover the mechanism underlying double fertilization, little knowledge has been acquired for understanding the molecular base of gamete recognition, mainly because of technical limitations. Still, progress has been made in terms of the mechanism, including the identification of candidate molecules that are involved in gamete recognition in angiosperms. New cues for gamete recognition have been found by the successful separation of the gametes and construction of gamete-specific cDNA libraries in several species, and the application of molecular approaches for studying this process by mutations. Thus, the topic is considered an abstruse but charming mystery.

关键词： central cell egg cell fertilization gamete recognition sperm cell.

Longitudinal profiled plate straightening process based on curvature integral method

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Journal of Iron and Steel Research International 2021年第3期28卷 291-302页

作者： Jian-liang sun Kai Li meng-qian sun Xiang-hui Lu Yan Peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina Department of Mechatronics Engineering Hebei Construction Material Vocational and Technical CollegeQinhuangdao066004HebeiChina

Considering the variable cross section thickness of longitudinal profiled plate and the dynamic reductions of straightening rolls,an analytical model combining curvature integral method with linear decreasing straightening scheme was proposed to investigate the longitudinal profiled plate straightening ***,the calculation flow and solution algorithm of longitudinal profiled plate straightening process were *** verify the proposed model,calculated straightening forces were compared with the measured values,and very good agreements were ***,the reduction,contact angle,reverse bending curvature,residual curvature,straightening force and straightening moment of longitudinal profiled plate in the straightening process were calculated and analyzed,and the calculated results show that the curvature integral method can be used to reveal the mechanism of longitudinal profiled plate straightening.

关键词： Longitudinal profiled plate straightening Curvature integral method Linear decreasing straightening scheme Residual curvature

Extracting terms from clinical records of traditional Chinese medicine

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Frontiers of Medicine 2014年第3期8卷 347-351页

作者： Cungen Cao meng sun Shi Wang Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Software College of Beihang University Beijing100191 China

Health records of traditional Chinese medicine contain valuable clinical inlormation which can be used for improvement of disease treatment and for medical research. In this paper, we present a practical iterative extraction method for extracting terms from the records. The method is based on a set of extraction rules, the Mesh, and the likelihood ratio technique, and achieved a precision rate of 88.18% and a recall rate of 94.21%.

关键词： term extraction rule-based likelihood ratio

Embryogenesis,a process of pattern formation

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Frontiers in Biology 2011年第1期6卷 1-2页

作者： meng-Xiang sun Key Laboratory of Ministry of Education for Plant Developmental Biology College of Life SciencesWuhan UniversityWuhan 430072China

Plant embryogenesis is traditionally defined as a developmental process from zygote to mature embryo,which has the potential to form a complete plant(Bhojwani,1974;Hu,2005).In dicotyledonous species,the fertilized egg or zygote usually divides according to a stereotyped pattern and gives rise to an embryo that consists of an embryonic shoot,cotyledons,hypocotyls,and an embryonic ***,the basic body plan of the plant is established during the ***,the shoot-leaf-stem structure,not including the root,is repeatedly photocopied as a basic unit throughout plant vegetative growth(Wolpert et al.,2002).In this case,embryogenesis is a seemingly endless process and the epitome of plant ***,recent studies on the molecular mechanism of embryogenesis revealed that the basic plant body plan is laid down as the establishment of the radial and apical-basal *** this process,both the radial concentric tissue layers and the apicalbasal sections of the plant body are generated,especially the root and shoot stem cell pools,which are essential for postembryonic growth(De Smet and Jürgens,2007;De Smet et al.,2010).All further development and morphogenesis are governed or guided by this basic ***,embryogenesis is,in fact,a process of pattern formation.

关键词： pattern process traditionally

The Feasibility of Constraining Dark Energy Using LAMOST Redshift Survey

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Chinese Journal of Astronomy and Astrophysics 2006年第2期6卷 155-164页

作者： Lei sun meng Su Zu-Hui Fan Department of Astronomy Peking University Beijing 100871

We consider using future redshift surveys with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） to constrain the equation of state of dark energy w. We analyze the Alcock ＆ Paczynski （AP） effect imprinted on the two-point correlation function of galaxies in redshift space. The Fisher matrix analysis is applied to estimate the expected error bounds of w0 and wα from galaxy redshift surveys, w0 and wα being the two parameters in the equation of state parametrization w（z） = w0 ＋ wαz/（1 ＋ z）. Strong degeneracies between w0 and wα are found. The direction of the degeneracy in w0 - wα plane, however, rotates counter-clockwise as the redshift increases. LAMOST can potentially contribute in the redshift range up to 0.5. In combination with other high redshift surveys, such as the proposed Kilo-Aperture Optical Spectrograph project （KAOS）, the joint constraint derived from galaxy surveys at different redshift ranges is likely to efficiently break the degeneracy of w0 and wα. We do not anticipate that the nature of dark energy can be well constrained with LAMOST alone, but it may help to reduce the error bounds expected from other observations, such as the Supernova/Acceleration Probe （SNAP）.

关键词： Cosmology: theory - galaxies: distances and redshifts - galaxy clustering - large-scale structure of Universe

New insights into cell-cell communications during seed development in flowering plants

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Journal of Integrative Plant Biology 2022年第2期64卷 215-229页

作者： Wei Wang Hanxian Xiong Kaiting sun Bo Zhang meng-Xiang sun State Key Laboratory of Hybrid Rice College of Life SciencesWuhan UniversityWuhan430072 China

The evolution of seeds is a major reason why flowering plants are a dominant life form on *** developing seed is composed of two fertilization products,the embryo and endosperm,which are surrounded by a maternally derived seed *** evidence indicates that efficient communication among all three seed components is required to ensure coordinated seed *** communication within plant seeds has drawn much attention in recent *** this study,we review current knowledge of cross-talk among the endosperm,embryo,and seed coat during seed development,and highlight recent advances in this field.

关键词： cell-cell communication embryo endosperm seed coat