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Distribution pattern of pelagic amphipods and its affecting facors in the East China Sea

Acta Oceanologica Sinica 2006年第5期25卷 112-119页

作者： XU Zhaoli jiang mei Key and Open Laboratory of Marine and Estuary Fisheries of Ministry of Agriculture East China Sea Fisheries Research Insti-tute Chinese Academy of Fisheries Sciences Shanghai 200090 China

On the basis of data from four seasonal cruises in the East China Sea （23°30′-33°N, 118°30′-128°E） from 1997 to 2000, horizontal distribution of amphipods, seasonal variations of abundance and their dynamic mechanisms were approached with quantitative and qualitative methods. Results showed that the average value of amphipod abundance in autumn was 115× 10^-2 ind./m^3, the highest in four seasons. The second occurred in summer with a mean value of 44×10^-2 ind./m^3and the lowest occurred in spring with a mean of 10 × 10^-2 ind./m^3. Amphipods were hardly observed in the north nearshore （ 29° 30′- 33° N and 122°30′- 125°E） in winter and spring. In all seasons, except for the north of the sea in autumn and the south in summer, the abundance in the offshore area was higher than that nearshore. The major species influencing the amphipod abundance were Lestrigonus schizogeneios in spring, L. macrophthalmus and L schizogeneios in summer,L bengalensis and Hyperioides sibaginis in autumn and Gammarus sp. in winter. The amphiped abundance showed a prominent linear correlation with the surface water temperature, but no significant correlation with both other water temperatures and salinity in spring. It was found that water temperature and salinity were not significantly correlated with the variation of amphiped abundance in summer, autumn and winter. In addition, the amphiped abundance in all four seasons can be linearly correlated with the bottom water temperature. The highest abundance area was located in the mixture waters near the side of warm water current in summer. Peak of amphiped abundance in autumn, not in summer told a temporal process for amphipeds to develop their populations. The continuance of warm current was beneficial to the development of amphipod abundance from summer to autumn. Amphipeds are kinds of very important diets for fishes in the offshore East China Sea.

关键词： East China Sea zooplankton pelagic amphipods abundance distribution

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A survey of deep learning-based 3D shape generation

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Computational Visual Media 2023年第3期9卷 407-442页

作者： qun-Ce Xu Tai-jiang Mu Yong-Liang Yang BNRist Department of Computer Science and TechnologyTsinghua UniversityBeijing 100084China Department of Computer Science University of BathBathUK

Deep learning has been successfully used for tasks in the 2D image *** on 3D computer vision and deep geometry learning has also attracted *** achievements have been made regarding feature extraction and discrimination of 3D *** recent advances in deep generative models such as generative adversarial networks,effective generation of 3D shapes has become an active research *** 2D images with a regular grid structure,3D shapes have various representations,such as voxels,point clouds,meshes,and implicit *** deep learning of 3D shapes,shape representation has to be taken into account as there is no unified representation that can cover all tasks *** such as the representativeness of geometry and topology often largely affect the quality of the generated 3D *** this survey,we comprehensively review works on deep-learning-based 3D shape generation by classifying and discussing them in terms of the underlying shape representation and the architecture of the shape *** advantages and disadvantages of each class are further *** also consider the 3D shape datasets commonly used for shape ***,we present several potential research directions that hopefully can inspire future works on this topic.

关键词： 3D representations geometry learning generative models deep learning

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Adaptive Backstepping Sliding Mode Control of Uncertain Semi-Strict Nonlinear Systems and Application to Permanent Magnet Synchronous Motor

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Journal of Systems Science & Complexity 2021年第2期34卷 552-571页

作者： WANG Fang WANG Jian-mei WANG Kun ZONG qun HUA Changchun School of Science Yanshan UniversityQinhuangdao 066004China School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China School of Electrical and Engineering Yanshan UniversityQinhuangdao 066004China

A disturbance observer(DOB)based-backstepping sliding mode control scheme is discussed for a class of semi-strict nonlinear system with unknown parameters and mismatched ***,adaptive technique and DOB are respectively applied to tackle the unknown parameters and mismatched uncertainty,where the DOB can effectively alleviate the chattering problem of sliding mode control(SMC).Then,exponential sliding mode surface is proposed to improve the convergence rate of the sliding mode ***‘explosion of complexity’problem inherent in conventional backstepping control is overcome by designing the novel first-order *** stability of the closed-loop system is analyzed in the framework of Lyapunov stability theory,in which the tracking error converges to an arbitrarily small neighborhood around zero(ASNZ).At last,two examples are given to illustrate the effectiveness of the proposed control strategy.

关键词： Adaptive law DOB filter semi-strict nonlinear system SMC

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The novel usage of thiourea nitrate in aryl nitration

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Chinese Chemical Letters 2014年第1期25卷 87-89页

作者： Ge Meng mei-Lin Zheng A-qun Zheng mei Wang Juan Shi School of Pharmacy Xi’an Jiaotong University School of Science Xi’an Jiaotong University

Thiourea nitrate （TN） was easily prepared from thiourea and nitric acid to explore its use as a new nitration reagent, Nitrations of various aromatic compounds utilizing TN in concentrated sulfuric acid were studied, TN could convert aromatic compounds to the corresponding nitrated derivatives with various abnormal yields under mild conditions. The results suggested that the reaction mechanism might be different from those of traditional nitration reagents.

关键词： Thiourea nitrate Nitration Thiourea Aromatic compounds

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Tribological behavior of AISI302 austenitic stainless steel modified by elevated temperature nitrogen plasma immersion ion implantation

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 301-304页

作者： jiang Shao-qun MA Xin-xin SUN Yue School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

AISI302 stainless steel samples were modified by elevated temperature nitrogen plasma immersion ion implantation at temperature ranging from 330 ℃ to 450 ℃. The tribological behaviors of the implanted layers of the samples were investigated. The samples were characterized by Auger electron spectroscopy (AES), glancing angle X-ray diffraction (GXRD), and nanoindentation. The results show that the implantation temperature plays an important rule on the microstructure and surface properties of the implanted layers. The thickness of the modified layer implanted at 390 ℃ is about 9 μm. It is improved about two orders compared with that of the implanted at room temperature. The surface nanohardness and the wear resistance of elevated temperature implanted layers increase significantly, and the friction coefficient decreases obviously in comparison with the unimplanted one. These data suggests that the improvement results from the formation of new phases such as ε-(Fe, Cr, Ni)2+xN, or noncrystal phase.

关键词： austenite stainless steel elevated temperature plasma immersion ion implantation tribology nanohardness

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Multi-view video color correction using dynamic programming

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1115-1120页

作者： Shao Feng jiang Gangyi Yu mei Faculty of Information Science and Engineering Ningbo Univ. Ningbo 315211 P. R. China National Key Lab of Software New Technology Nanjing Univ. Nanjing 210093 P. R. China

Color inconsistency between views is an important problem to be solved in multi-view video systems. A multi-view video color correction method using dynamic programming is proposed. Three-dimensional histograms are constructed with sequential conditional probability in HSI color space. Then, dynamic programming is used to seek the best color mapping relation with the minimum cost path between target image histogram and source image histogram. Finally, video tracking technique is performed to correct multi-view video. Experimental results show that the proposed method can obtain better subjective and objective performance in color correction.

关键词： multi-view video color correction dynamic programming video tracking

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Numerical simulation of pedestrian flow past a circular obstruction

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Acta Mechanica Sinica 2011年第2期27卷 215-221页

作者： Yan-qun jiang Ru-Xun Liu Ya-Li Duan Department of Mathematics Southwest University of Science and Technology 621010 Mianyang China Department of Mathematics University of Science and Technology of China 230026 Hefei China

In this paper, a revisiting Hughes’ dynamic continuum model is used to investigate and predict the essential macroscopic characteristics of pedestrian flow, such as flow, density and average speed, in a two dimensional continuous walking facility scattered with a circular obstruction. It is assumed that pedestrians prefer to walk a path with the lowest instantaneous travel cost from origin to destination, under the consideration of the current traffic conditions and the tendency to avoid a high-density region and an obstruction. An algorithm for the pedestrian flow model is based on a cellcentered finite volume method for a scalar conservation law equation, a fast sweeping method for an Eikonal-type equation and a second-order TVD Runge-Kutta method for the time integration on unstructured meshes. Numerical results demonstrate the effectiveness of the algorithm. It is verified that density distribution of pedestrian flow is influenced by the position of the obstruction and the path-choice behavior of pedestrians.

关键词： Pedestrian flow · Continuum model ·Finite volume method · Unstructured meshes · Obstruction

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Effect of precipitates on high-temperature strength and irradiation behavior of vanadium-based alloys

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Journal of Iron and Steel Research International 2018年第12期25卷 1270-1277页

作者： Shao-ning jiang Li-qun Xu Fa-rong Wan School of Mechanical and Automotive Engineering Qilu University of Technology (Shandong Academy of Science) Jinan 250353ShandongChina School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The formation of precipitates and their effect on mechanical properties and irradiation damage in V-4CraTi alloys have been investigated using transmission electron microscope,high-temperature tensile tests and high-voltage electron microscope (HVEM).V-4Cr-4Ti alloys were aged for 20-40 h at 873 K,and extremely fine precipitates were produced during the aging process,which coarsened with aging *** results of high-temperature (773,873 and 973 K)tensile tests showed an increase in strength with increasing aging time (i.e:,increasing size of precipitates)while a decrease in the uniform *** was evidence that presence of precipitates strengthened V-4Cr-4Ti *** situ HVEM observations showed that the precipitates restricted the growth rate of dislocation loops induced during electron irradiation at 773 *** interactions between precipitates and irradiation-induced dislocation loops were *** presence of particles alleviated the increase in irradiation hardening up to an irradiation dose of 3.42 dpa (displacement per atom).The precipitates shrank in size during electron irradiation,which was due to the dissolution of constituent atoms of the precipitates into the alloy matrix.

关键词： Aging Precipitate strengthening Electron irradiation Irradiation defect Dislocation loop

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The RNAome landscape of tomato during arbuscular mycorrhizal symbiosis reveals an evolving RNA layer symbiotic regulatory network

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Plant Communications 2023年第1期4卷 148-166页

作者： Zhen Zeng Yang Liu Xing-Yu Feng Sai-Xi Li Xing-mei jiang Jian-qun Chen Zhu-Qing Shao State Key Laboratory of Pharmaceutical Biotechnology School of Life SciencesNanjing UniversityNanjing 210023China

Arbuscular mycorrhizal symbiosis(AMS)is an ancient plant-fungus relationship that is widely distributed in terrestrial *** formation of symbiotic structures and bidirectional nutrient exchange requires the regulation of numerous ***,the landscape of RNAome during plant AMS involving different types of regulatory RNA is poorly *** this study,a combinatorial strategy utilizing multiple sequencing approaches was used to decipher the landscape of RNAome in tomato,an emerging AMS *** annotation of the tomato genome was improved by a multiple-platform sequencing strategy.A total of 3,174 protein-coding genes were upregulated during AMS,42%of which were alternatively ***-transcriptome analysis revealed that genes from 24 orthogroups were consistently induced by AMS in eight phylogenetically distant *** additional orthogroups were specifically induced by AMS in all surveyed dicot AMS host ***,these orthogroups were absent or not induced in monocots and/or non-AMS hosts,suggesting a continuously evolving AMS-responsive network in addition to a conserved core regulatory ***,we detected 587 lncRNAs,ten miRNAs,and 146 circRNAs that responded to AMS,which were incorporated to establish a tomato AMSresponsive,competing RNA-responsive endogenous RNA(ceRNA)***,a tomato symbiotic transcriptome database(TSTD,https://***/TSTD)was constructed to serve as a resource for deep deciphering of the AMS regulatory *** results help elucidate the reconfiguration of the tomato RNAome during AMS and suggest a sophisticated and evolving RNA layer responsive network during AMS processes.

关键词： tomato RNAome landscape arbuscular mycorrhizal symbiosis evolution ceRNA network

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EXPERIMENTAL RESEARCH ON A SUPERCAVITATING SLENDER BODY OF REVOLUTION WITH VENTILATION

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Journal of Hydrodynamics 2002年第2期14卷 17-23页

作者： Feng, Xue-mei Lu, Chuan-Jing Hu, Tian-qun Dept. of Eng. Mech. Shanghai Jiaotong Univ. Shanghai 200240 China

The behavior of supercavitating and cavitatlng flow around a conical body of revolution with and without ventilation at several angles of attack was studied experimentally. The hydrodynamic forces for a range of cavitation number were measured. Comparisons of the appearance and the hydrodynamic forces in condition of cavity with and without ventilation were made over the same range of the cavitation number, and a well agreement was obtained. The changes of the drag were especially studied. The experimental results showed that the drag of the model decreased with the presence of supercavity under the ventilation condition.

关键词： Angle measurement Bodies of revolution Drag Force control Ventilation

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