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A Region-Based Analysis for the Feature Concatenation in Deep Forests

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Chinese Journal of Electronics 2022年第6期31卷 1072-1080页

作者： LYU shen-huan CHEN Yi-He ZHOU Zhi-Hua National Key Laboratory for Novel Software Technology Nanjing University

Deep forest is a tree-based deep model made up of non-differentiable modules that are trained without backpropagation. Despite the fact that deep forests have achieved considerable success in a variety of tasks, feature concatenation, as the ingredient for forest representation learning, still lacks theoretical understanding. In this paper, we aim to understand the influence of feature concatenation on predictive performance. To enable such theoretical studies, we present the first mathematical formula of feature concatenation based on the two-stage structure, which regards the splits along new features and raw features as a region selector and a region classifier respectively. Furthermore, we prove a region-based generalization bound for feature concatenation,which reveals the trade-off between Rademacher complexities of the two-stage structure and the fraction of instances that are correctly classified in the selected *** a consequence, we show that compared with the prediction-based feature concatenation(PFC), the advantage of interaction-based feature concatenation(IFC) is that it obtains more abundant regions through distributed representation and alleviates the overfitting risk in local regions. Experiments confirm the correctness of our theoretical results.

关键词： trees (mathematics) raw features pattern classification deep learning (artificial intelligence) deep forest prediction-based feature concatenation forest representation learning tree-based deep model learning (artificial intelligence) region-based generalization feature extraction region-based analysis backpropagation interaction-based feature concatenation

Steering control strategy guide by two preview vision cues

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Science China(Technological Sciences) 2012年第9期55卷 2662-2670页

作者： shen huan LING Rui MAO JianGuo LI ShunMing College of Energy&Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Vision cues play an important role in states feedback in motion ***,the existing driver steering models consider little about vision cues utilized by human drivers during their steering *** paper presents a novel steering control strategy based on two preview points(far point and near point).The far point is used to compensate the steering wheel by predicting the upcoming curvature change with respect to the lane,while the near point as vision feedback,which is used to tune the steering wheel by estimating the errors of vehicle states and lane *** obtain much smoother lateral acceleration during steering,a forward internal model is established using a second-order yaw dynamics system that captures the influence of yaw angular acceleration caused by steering wheel *** input parameter of the second-order system is the vision cues of both the near and far points,and the output parameters are the ideal yaw angle and yaw *** calculate suitable the steering wheel angle,an adaptive controller is designed using fuzzy sliding technology,which is used as the input of the vehicle system *** simulation results show that the proposed method performs better than the existing driver steering models in case of imitating human drivers' behavior,and exhibits excellent adaption to the lane curvature change.

关键词： autonomous driving lateral control driver model fuzzy logic cognitive vehicle

The Unique Strategies of Flight Initiation Adopted by Butterflies on Vertical Surfaces

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Journal of Bionic Engineering 2021年第4期18卷 840-856页

作者： huan shen Aihong Ji Qian Li Wei Wang Guodong Qin Qingfei Han Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China

As the basis of flight behavior,the initiation process of insect flight is accompanied by a transition from crawling mode to flight mode,and is clearly important and *** take flight from a vertical surface,which is more difficult than takeoff from a horizontal plane,but greatly expands the space of activity and provides us with an excellent bionic *** this study,the entire process of a butterfly alighting from a vertical surface was captured by a high-speed camera system,and the movements of its body and wings were accurately measured for the first *** analyzing the movement of the center of mass,it was found that before initiation,the acceleration perpendicular to the wall was much greater than the acceleration parallel to the wall,reflecting the positive effects of the legs during the initiation ***,the angular velocity of the body showed that this process was unstable,and was further destabilized as the flight speed *** the angles between the body and the vertical direction before and after leaving the wall,a significant change in body posture was found,evidencing the action of aerodynamic forces on the *** movement of the wings was further analyzed to obtain the laws of the three Euler angles,thus revealing the locomotory mechanism of the butterfly taking off from the vertical surface.

关键词： flight initiation butterfly vertical surface body and wing kinematics speed and stability strategies

ON THE COASTAL ECONOMIC ZONE AROUND THE YELLOW SEA & BOHAI SEA——Features & Comparative Advantages in Regional Economic Cooperation

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南开经济研究 1994年第S2期 12-20页

作者： Chen Yue NANKAI UNIVERSITY shen huan

Since the middle of the nineteen-eighties, there haveemerged in Northeast Asia many circles or economic zones of whichthe concept of the coastal region around the Yellow Sea and

关键词： Features

Liver transplantation due to cerebrotendinous xanthomatosis end-stage liver disease

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World Journal of Pediatrics 2018年第4期14卷 414-415页

作者： Cong-huan shen Zheng-Xin Wang Department of General Surgery Affiliated Huashan Hospital of Fudan University796 Jiang Su RoadShanghai 200040China

Cerebrotendinous xanthomatosis (CTX) is an autosomal recessive disease characterized by an increase in plasma concentrations of cholestanol and storage of sterols in mul-tiple tissues, especially tendons and the nervous system (1)Neonatal cholestatic jaundice has been rarely reported, but patients may progress to cirrhosis if effective treatment is not provided. Mutations in theCYP27A1 gene leads to decreased synthesis of bile acid, excessive production of cholestanol, and consequent accumulation of cholestanol in tissues in patients with CTX (2)The liver is rarely affected in these patients;however, neonatal cholestatic jaundice can be self-limiting. Reports on liver transplantation for CTX are lacking. Liver transplantation not only cures the liver disease, but also introduces the normalCYP27A1 gene into the patient, which can be potentially beneficial.

关键词： Liver transplantation cerebrotendinous xanthomatosis end-stage liver disease

Effects of Morphological Integrity of Secondary Feather on Their Drag Reduction in Pigeons

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Journal of Bionic Engineering 2022年第5期19卷 1422-1438页

作者： Qian Li huan shen Qingfei Han Aihong Ji Zhendong Dai Stanislav N.Gorb Institute of Bio-Inspired Structure and Surface Engineering College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing 210016China Department of Functional Morphology and Biomechanics Kiel UniversityAm Botanischen Garten 924118 KielGermany

Flight feathers of birds interact with the air flow during *** the observed low drag and high lift values at wind speeds from 9.0 to 19.8 m/s can be achieved due to the feather aerodynamics remains *** the present paper,we tested and compared morphological changes,drag reduction and flow visualization results of intact,damaged,and artificial feathers at different wind speeds in a wind *** the analysis of the drag force and resultant force angle,we proved that the integrity of feathers,whose barbs are usually closely interconnected,played an important role in the drag,which potentially triggers excellent drag reduction *** wind tunnel tests indicated that intact secondary feathers had a surprisingly high maximum drag reduction property at v?=?9 m/s compared with the feathers,where the integrity of barbs was *** hook cascades facilitated elasticity under pressure and suitable permeability in an intact feather,when the hooks were *** was indicated that the suitable permeability of intact feathers would prevent flow separation and reduce drag force at low wind speed;at high wind speed,elasticity under pressure and suitable permeability in an intact feather would facilitate strong squeezing effect,helping feathers withstand larger aerodynamic forces to which they might be subjected during *** was revealed that the intact secondary feather is a compromise between strong lift generation and drag reduction,which has a great significance for the bird’s flight.

关键词： Morphological integrity Secondary feather Drag reduction Wind tunnel Smoke visualization Bioinspiration

Synergistic Copper and Chiral Lewis Base Catalysis for the Asymmetric Synthesis of Pyrrolo[1,2-a]indoles

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Chinese Journal of Chemistry 2021年第12期39卷 3292-3296页

作者： Jia-huan shen Fei Tian Wu-Lin Yang Wei-Ping Deng Shanghai Key Laboratory of New Drug Design and School of Pharmacy East China University of Science and Technology130 Meilong RoadShanghai 200237China

The first asymmetric decarboxylative[3+2]-cycloaddition of ethynyl indoloxazolidones with carboxylic acids has been developed under synergistic catalysis of copper and chiral Lewis *** protocol provides a direct and modular approach to biologically important pyrrolo[1,2-a]indoles bearing two vicinal stereogenic centers with excellent diastereo-and enantioselectivities(up to>20:1 dr and>99%ee).In addition,the utility of this methodology was demonstrated by scaled-up reaction and several synthetic transformations of the cycloadduct.

关键词： Copper Lewis base Synergistic catalysis Pyrrolo[1,2-a]indoles Asymmetric synthesis

Design and Theoretical Research on Aerial-Aquatic Vehicles:A Review

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Journal of Bionic Engineering 2023年第6期20卷 2512-2541页

作者： Yi Sun Xuefei Liu Kai Cao huan shen Qian Li Guangming Chen Jiajun Xu Aihong Ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringState Key Laboratory of Mechanics and Control for Aerospace StructuresNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

With the rapid development of unmanned aerial and underwater vehicles,various tasks,such as biodiversity monitoring,surveying,and mapping,as well as,search and rescue can now be completed in a single medium,either underwater or in the *** systematically examining the water–air cross-medium locomotion of organisms,there has been growing interest in the development of aerial-aquatic *** goal of this review is to provide a detailed outline of the design and cross-medium theoretical research of the existing aerial-aquatic vehicles based on the research on the organisms capable of transiting between water and *** these designs and theoretical frameworks have been validated in many aerial-aquatic vehicles,there are still many problems that need to be addressed,such as inflexible underwater motion and unstable medium *** a result,supplementation of the existing cross-medium biomimetic research,vehicle design,power selection,and cross-medium theory is urgently required to optimize the key technologies in ***,by summarizing the existing designs and theoretical approaches on aerial-aquatic vehicles,including biomimetic research on water–air cross-medium locomotion in nature,different power selections,and cross-medium theoretical research,the relative problems and development trends on aerial-aquatic vehicles were thoroughly explored,providing significant help for the subsequent research process.

关键词： Aerial-aquatic vehicle Cross-medium motion Power selection Control theory Biomimetic

TPFTZ(Tianjin Port Free Trade Zone)——A New Pattern of China's Openning to the Outside World

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南开经济研究 1994年第S1期 35-39,20页

作者： Zhu Qinyuan: Director of Administrative Committe of the TPFTZ shen huan

Under the guidance of Deng Xiao-ping’s strategic think-ing of openning to the outside world, the structure of om-nibearing openness has basically taken shape in China. Follow-

关键词： Free TPFTZ Tianjin Port Free Trade Zone A New Pattern of China’s Openning to the Outside World