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Analysis of Influencing Factors on Lift Coefficients of Autonomous Sailboat Double Sail Propulsion System Based on Vortex Panel Method

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China Ocean Engineering 2019年第6期33卷 746-752页

作者： sun zhao-yang YU Jian-cheng ZHANG Ai-qun JIN Qian-long State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

Sail is the core part of autonomous sailboat and wing sail is a new type of sail. Wing sail generates not only propulsion but also lateral force and heeling moment. The latter two will affect the navigation status and bring resistance. Double sail can effectively reduce the center of wind pressure and heeling moment. In order to study the effect of distance between two sails, airfoil and attack angle on the total lift coefficient of double sail propulsion system, pressure coefficient distribution and lift coefficient calculation model have been established based on vortex panel method. By using the basic finite solution, the fluid dynamic forces on the two-dimensional sails are *** results show that, the distance in the range of 0 to 1 time chord length, when using the same airfoil in the fore and aft sail, the total lift coefficient of the double sail increases with the increase of distance, finally reaches a stable value in the range of one to three times chord length. Lift coefficients of thicker airfoils are more sensitive to the change of distance. The thicker the airfoil, the longer distance is required of the total lift coefficient toward *** different airfoils are adopted in fore and aft sail, the total lift coefficient increases with the increase of the thickness of aft sail. The smaller the thickness difference is, the more sensitive to the distance change the lift coefficient is. The thinner the fore sail is, the lower the influence will be on the lift coefficient of aft sail.

关键词： autonomous sailboat wing sail double sail vortex panel method lift coefficient

Distribution of persistent organochlorine pesticides in tissue/organ of silver carp (Hypophthalmichthys molitrix) from Guanting Reservoir, China

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Journal of Environmental Sciences 2005年第5期17卷 722-726页

作者： sun yang-zhao WANG Xue-tong LI Xing-hong XU Xiao-bai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 China

The concentration of organochlorine pesticides（OCPs） in tissues and organs of silver carp（Hypophthalmichthys mofitrix） from Guanting Reservoir were investigated to evaluate the pollution potential and distribution of OCPs. A total of 16 OCPs were measured and the concentrations were in the range of 1.61-69.01 ng/g wet weight（ww） for total OCPs, 0.16- 0.75 ng/g ww for HCB. 0.75 -26.80 ng/g ww for SHCH（sum of α-,β-, γ- and δ-HCH） and 0.68-35.94 ng/g ww for SDDT（ sum of p, p＇-DDE, p, p＇-DDD, o, p＇-DDT and p, p＇- DDT）. The mean concentrations of total OCPs, HCB, ∑HCH, and ∑DDT were 18.04, 0.96, 7.14 and 9.28 ng/g ww, respectively. Among the organochlorine pesticides, β-HCH and p, p＇-DDE were the most dominant compounds in tissue and organ with the average concentrations of 4.42 and 8.14 ng/g, respectively. The results obtained in this study show that the levels of 16 OCP residues found in silver carps are low and pose no threat to human health and wildlife fed upon them on the basis of existing related quality guidelines. However, recent input of lindane and DDT might still exist in the area investigated and further investigation should be carried on.

关键词： organochlorine pesticides silver carp distribution Guanting Reservoir

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狐肉骨粉安全性能评价

饲料研究 2024年第8期47卷 121-125页

作者：谭展清李光玉孙伟丽赵海平隗晗高娅薇孙朝阳刘可园青岛农业大学动物科技学院山东青岛266109 河北省特色动物种质资源挖掘与创新重点实验室河北秦皇岛066004

试验使用狐屠体生产肉骨粉,旨在研究狐屠体制作肉骨粉的可行性,评价狐肉骨粉安全性。试验分别从我国13个狐主要养殖区中随机选取处于取皮期、体重15 kg左右健康蓝狐3只(共39只)。狐屠体(含内脏和趾爪),经过绞碎、高压水解、脱脂、烘干... 详细信息

试验使用狐屠体生产肉骨粉,旨在研究狐屠体制作肉骨粉的可行性,评价狐肉骨粉安全性。试验分别从我国13个狐主要养殖区中随机选取处于取皮期、体重15 kg左右健康蓝狐3只(共39只)。狐屠体(含内脏和趾爪),经过绞碎、高压水解、脱脂、烘干、粉碎等程序制作成肉骨粉,分别测定常规营养成分、重金属、兽药残留以及犬瘟热病毒,进行安全性评价。结果表明,肉骨粉中的粗蛋白含量在55%~67%之间,符合《饲料用骨粉及肉骨粉》一级指标中粗蛋白的要求。铅、砷、汞、镉、铬重金属元素含量符合国标对肉骨粉卫生安全标准的要求。磺胺二甲嘧啶、磺胺甲恶唑、磺胺间甲氧嘧啶、磺胺嘧啶、青霉素、土霉素和庆大霉素符合食品中对兽药最大残留限量的标准要求。研究表明,狐肉骨粉的营养价值丰富,卫生和安全指标满足蛋白质饲料原料标准。

关键词：狐屠体肉骨粉安全评价

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An Accurate Numerical Scheme for Mean-Field Forward and Backward SDEs with Jumps

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 243-274页

作者： Yabing sun Jie yang Weidong zhao College of Science National University of Defense TechnologyChangsha 410073China School of Mathematics and Statistics Shandong UniversityWeihai 264209China School of Mathematics Shandong UniversityJinan 250100China

In this work,we propose an explicit second order scheme for decoupled mean-ﬁeld forward backward stochastic differential equations with *** sta-bility and the rigorous error estimates are presented,which show that the proposed scheme yields a second order rate of convergence,when the forward mean-ﬁeld stochastic differential equation is solved by the weak order 2.0 Itˆo-Taylor *** experiments are carried out to verify the theoretical results.

关键词： Mean-field forward backward stochastic differential equation with jumps stability analysis error estimates

Causal reasoning in typical computer vision tasks

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Science China(Technological Sciences) 2024年第1期67卷 105-120页

作者： ZHANG KeXuan sun QiYu zhao ChaoQiang TANG yang Key Laboratory of Advanced Control and Optimization for Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China National Key Laboratory of Air based Information Perception and Fusion Luoyang 471000China Luoyang Institute of Electro Optical Equipment of Avic Luoyang 471000China

Deep learning has revolutionized the field of artificial *** on the statistical correlations uncovered by deep learning-based methods,computer vision tasks,such as autonomous driving and robotics,are growing *** being the basis of deep learning,such correlation strongly depends on the distribution of the original data and is susceptible to uncontrolled *** the guidance of prior knowledge,statistical correlations alone cannot correctly reflect the essential causal relations and may even introduce spurious *** a result,researchers are now trying to enhance deep learningbased methods with causal *** theory can model the intrinsic causal structure unaffected by data bias and effectively avoids spurious *** paper aims to comprehensively review the existing causal methods in typical vision and visionlanguage tasks such as semantic segmentation,object detection,and image *** advantages of causality and the approaches for building causal paradigms will be *** roadmaps are also proposed,including facilitating the development of causal theory and its application in other complex scenarios and systems.

关键词： causal reasoning computer vision tasks vision-language tasks semantic segmentation object detection

Broadband intelligent programmable metasurface with polarization-modulated self-adaptive electromagnetic functionality switching

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Photonics Research 2024年第7期12卷 1395-1409页

作者： XIMING LI RUI XU XIAOFENG sun YUAN zhao zhao yang GUOHONG DU College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China

Programmable metasurfaces have received a great deal of attention due to their ability to dynamically manipulate electromagnetic(EM) waves. Despite the rapid growth, most of the existing metasurfaces require manual control to switch among different functionalities, which poses severe limitations on practical applications. Here, we put forth an intelligent metasurface that has self-adaptive EM functionality switching in broadband without human participation. It is equipped with polarization discrimination antennas(PDAs) and feedback components to automatically adjust functionalities for the different incident polarization information.

关键词： equipped adjust polarization

Visual Semantic Segmentation Based on Few/Zero-Shot Learning:An Overview

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1106-1126页

作者： Wenqi Ren yang Tang Qiyu sun Chaoqiang zhao Qing-Long Han Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China National Key Laboratory of Air-Based Information Perception and Fusion Aviation Industry Corporation of ChinaLuoyang 471000China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

Visual semantic segmentation aims at separating a visual sample into diverse blocks with specific semantic attributes and identifying the category for each block,and it plays a crucial role in environmental *** learning-based visual semantic segmentation approaches count heavily on largescale training data with dense annotations and consistently fail to estimate accurate semantic labels for unseen *** obstruction spurs a craze for studying visual semantic segmentation with the assistance of few/zero-shot *** emergence and rapid progress of few/zero-shot visual semantic segmentation make it possible to learn unseen categories from a few labeled or even zero-labeled samples,which advances the extension to practical ***,this paper focuses on the recently published few/zero-shot visual semantic segmentation methods varying from 2D to 3D space and explores the commonalities and discrepancies of technical settlements under different segmentation ***,the preliminaries on few/zeroshot visual semantic segmentation,including the problem definitions,typical datasets,and technical remedies,are briefly reviewed and ***,three typical instantiations are involved to uncover the interactions of few/zero-shot learning with visual semantic segmentation,including image semantic segmentation,video object segmentation,and 3D ***,the future challenges of few/zero-shot visual semantic segmentation are discussed.

关键词： Visual segmentation separating

Flexible, self-cleaning, and high-performance ceramic nanofiber-based moist-electric generator enabled by interfacial engineering

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Science China(Technological Sciences) 2022年第2期65卷 450-457页

作者： WANG LiMing FENG LanLan sun zhao yang HE Xinyang WANG RongWu QIN XiaoHong YU JianYong Key Laboratory of Textile Science&Technology Ministry of EducationCollege of TextilesDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China

Due to their long-term stability, even under extreme conditions, oxide ceramics have attracted significant attention in emerging fields like moist-electric generation. However, the inherent brittleness and low voltage output of oxide ceramic-based moistelectric generators(MEGs) limit their applications in wearable electronics. Herein, a facile strategy involving the combination of sol-gel electrospinning and calcination is used to fabricate flexible and freestanding Ti O_(2)/Zr O_(2)(TZ) composite nanofiber-based MEGs. The excellent flexibility of the TZ nanofiber membranes can be attributed to the suppression of their crystal structure transformation, dispersion of stress concentration, and reduction of crack propagation via interfacial engineering. The porous structure of the electrospun nanofiber membrane features an abundance of charged narrow channels for the diffusion of water molecules and generates a streaming potential. The optimal voltage output reached ~0.8 V, which is the highest value reported for an oxide ceramic-based MEG. Furthermore, the as-fabricated nanofiber-based MEG exhibits good self-cleaning capability to degrade organic pollutants under ultraviolet irradiation. By integrating mechanical flexibility, high performance, and a selfcleaning effect, this work presents a new idea for exploring diverse, efficient, and wearable oxide ceramic-based MEGs.

关键词： moist-electric generation ceramic nanofiber electrospinning flexible self-cleaning

Exploring the Interplay between Local Chain Structure and Stress Distribution in Polymer Networks

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Chinese Journal of Polymer Science 2024年第6期42卷 874-885页

作者： Jin-Tong Xue yang Bai Li Peng Xian-Bo Huang zhao-Yan sun School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China National-certified Enterprise Technology Center Kingfa Science and Technology Co.Ltd.Guangzhou510663China

The mechanical behavior of polymer networks is intrinsically correlated with the local chain topology and chain *** this study,we delve into this relationship through the lens of coarse-grained molecular dynamics(CG-MD)*** aim is to illuminate the intricate interplay between local topology and stress distribution within polymer monomers,cross-linkers,and various components with distinct cross-link connections,thereby elucidating their collective impact on the mechanical properties of polymer *** mainly focus on how specific local structures contribute to the overall mechanical response of the *** particular,we employ local stress analysis to unravel the mechanics of these *** findings reveal the diverse responses of individual components,such as junctions,strands,cross-linkers between junctions,and dangling chain ends,when subjected to ***,we observe that these components exhibit varying degrees of deformation tolerance,underscoring the significance of their roles in determining the mechanical characteristics of the *** investigations highlight junctions as primary contributors to stress accumulation,and particles with higher local stress showing a stronger correlation between stress and Voronoi ***,our results indicate that both strands and cross-linkers between junctions exhibit heightened stress levels as strand lengths *** study enhances our understanding of the multifaceted factors governing the mechanical attributes of cross-linked polymer systems at the microstructural level.

关键词： Local chain structure Local stress Molecular dynamics simulation