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3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles
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作者 Dun Cao Jia Ru +3 位作者 Jian Qin Amr Tolba Jin Wang Min Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1365-1384,共20页
Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transp... Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time complexity.Network modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is established.This paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety. 展开更多
关键词 Internet of vehicles road networks 3D road model structure recognition GIS
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Assembly and analysis of the Populus deltoides mitochondrial genome:the first report of a multicircular mitochondrial conformation for the genus Populus
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作者 Yanshu Qu Pengyan Zhou +2 位作者 Chunfa Tong Changwei Bi Li’an Xu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期717-733,共17页
Genomics research of Populus deltoides,an important timber species that is widely planted worldwide,is an important part of poplar breeding.Currently,the nuclear and chloroplast genome of P.deltoides have been sequenc... Genomics research of Populus deltoides,an important timber species that is widely planted worldwide,is an important part of poplar breeding.Currently,the nuclear and chloroplast genome of P.deltoides have been sequenced,but its mitochondrial genome(mitogenome)has not been reported.To further explore the evolution and phylogeny of P.deltoides,the mitogenome of P.deltoides I-69 was assembled using reads from Nanopore and Illumina sequencing platforms and found to consist of 802,637 bp and three circular chromosomes(336,205,280,841,and 185,591 bp)containing 58 genes(34 protein-coding genes,21 tRNA genes,and 3 rRNA genes).RNA analysis in combination with several species showed signifi cantly fewer RNA editingsites in the mitogenomes of poplar and other angiosperms than in gymnosperms.Sequence transfer analysis showed extensive mitogenome rearrangements in Populus species,and with evolution from lower to higher plants,tRNA transfer from chloroplasts to mitochondria became increasingly frequent.In a phylogenetic analysis,the evolutionary status of P.deltoides was determined,and the section Populus was supported.Our results based on the fi rst report of a multicircular conformation of the Populus mitogenome provide a basis for further study of the evolution and genetics of P.deltoides and other Populus species and for breeding programs. 展开更多
关键词 Mitochondrial genome Multi-circular Populus deltoids Comparative genomics PHYLOGENY
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Automatic Quality Inspection of Bakery Products Based on Shape and Color Information 被引量:2
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作者 Babar Khan Fang Han +1 位作者 Zhijie Wang Ather Iqbal 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第5期88-96,共9页
An automatic intelligent system for the colour and texture inspection of bakery products is proposed.In this system,advance classification technique featuring Support Vector Machine and biologically inspired HMAX base... An automatic intelligent system for the colour and texture inspection of bakery products is proposed.In this system,advance classification technique featuring Support Vector Machine and biologically inspired HMAX based shape descriptor integrated with biologically plausible RGB Opponent-Colour-Channel Descriptor is used to classify bakery products to their respective classes based on the shape and based on their colour referring to different baking durations. The results of this paper are compared with other methods for the automatic bakery products inspection. It is discovered that biologically inspired computer vision models performs accurately and efficiently as compared to the computer vision models which are not biologically plausible,in the bakery products quality inspection. It is also discovered that the One Versus One SVM and Directed Acyclic Graph SVM acquired the maximum accurate classification rate. The proposed method acquired classification accuracy of 95% and 100% for the biscuit shape and biscuit colour recognition,respectively. The proposed method is also consistently stable and invariant. This shows that the biologically inspired computer vision models have the capability to replace existing inspection methods as more reliable and accurate alternative. 展开更多
关键词 BAKERY products quality inspection computer VISION HMAX OPPONENT COLOR channel RGB COLOR DESCRIPTOR Support VECTOR Machine (SVM)
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Research and Application of Log Defect Detection and Visualization System Based on Dry Coupling Ultrasonic Method
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作者 Yongning Yuan Dong Zhang +4 位作者 Usama Sayed Hao Zhu Jun Wang Xiaojun Yang Zheng Wang 《Journal of Renewable Materials》 EI 2023年第11期3917-3932,共16页
In order to optimize the wood internal quality detection and evaluation system and improve the comprehensive utilization rate of wood,this paper invented a set of log internal defect detection and visualization system... In order to optimize the wood internal quality detection and evaluation system and improve the comprehensive utilization rate of wood,this paper invented a set of log internal defect detection and visualization system by using the ultrasonic dry coupling agent method.The detection and visualization analysis of internal log defects were realized through log specimen test.The main conclusions show that the accuracy,reliability and practicability of the system for detecting the internal defects of log specimens have been effectively verified.The system can make the edge of the detected image smooth by interpolation algorithm,and the edge detection algorithm can be used to detect and reflect the location of internal defects of logs accurately.The content mentioned above has good application value for meeting the requirement of increasing demand for wood resources and improving the automation level of wood nondestructive testing instruments. 展开更多
关键词 Ultrasonic method log defect detection visualization system dry coupling B-scan pulse transmission method bilinear image interpolation algorithm edge detection algorithm
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Optimal Quota-Share and Excess-of-Loss Reinsurance and Investment with Heston’s Stochastic Volatility Model
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作者 伊浩然 舒慧生 单元闯 《Journal of Donghua University(English Edition)》 CAS 2023年第1期59-67,共9页
An optimal quota-share and excess-of-loss reinsurance and investment problem is studied for an insurer who is allowed to invest in a risk-free asset and a risky asset.Especially the price process of the risky asset is... An optimal quota-share and excess-of-loss reinsurance and investment problem is studied for an insurer who is allowed to invest in a risk-free asset and a risky asset.Especially the price process of the risky asset is governed by Heston's stochastic volatility(SV)model.With the objective of maximizing the expected index utility of the terminal wealth of the insurance company,by using the classical tools of stochastic optimal control,the explicit expressions for optimal strategies and optimal value functions are derived.An interesting conclusion is found that it is better to buy one reinsurance than two under the assumption of this paper.Moreover,some numerical simulations and sensitivity analysis are provided. 展开更多
关键词 optimal reinsurance optimal investment quota-share and excess-of-loss reinsurance stochastic volatility(SV)model exponential utility function
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Path Planning of UAV by Combing Improved Ant Colony System and Dynamic Window Algorithm
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作者 徐海芹 邢浩翔 刘洋 《Journal of Donghua University(English Edition)》 CAS 2023年第6期676-683,共8页
A fusion algorithm is proposed to enhance the search speed of an ant colony system(ACS)for the global path planning and overcome the challenges of the local path planning in an unmanned aerial vehicle(UAV).The ACS sea... A fusion algorithm is proposed to enhance the search speed of an ant colony system(ACS)for the global path planning and overcome the challenges of the local path planning in an unmanned aerial vehicle(UAV).The ACS search efficiency is enhanced by adopting a 16-direction 24-neighborhood search way,a safety grid search way,and an elite hybrid strategy to accelerate global convergence.Quadratic planning is performed using the moving average(MA)method.The fusion algorithm incorporates a dynamic window approach(DWA)to deal with the local path planning,sets a retracement mechanism,and adjusts the evaluation function accordingly.Experimental results in two environments demonstrate that the improved ant colony system(IACS)achieves superior planning efficiency.Additionally,the optimized dynamic window approach(ODWA)demonstrates its ability to handle multiple dynamic situations.Overall,the fusion optimization algorithm can accomplish the mixed path planning effectively. 展开更多
关键词 ant colony system(ACS) dynamic window approach(DWA) path planning dynamic obstacle
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Compression Mechanical Performance Simulation and Parameter Optimization of Degradable Ureteral Stent Based on ABAQUS
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作者 刘璐 刘肖燕 郝矿荣 《Journal of Donghua University(English Edition)》 CAS 2023年第1期1-7,共7页
The compression performance of a degradable ureteral stent is analyzed and the parameters are optimized by a finite element modeling method.The degradable ureteral stent explored in this paper is developed from poly(g... The compression performance of a degradable ureteral stent is analyzed and the parameters are optimized by a finite element modeling method.The degradable ureteral stent explored in this paper is developed from poly(glycolic acid)(PGA)and poly(lactic-co-glycolic acid)(PLGA)degradable materials.Based on the actual measurement of fabric structure parameters,the three-dimensional model of the stent is established with the help of the modeling software.The finite element analysis software is used to simulate the compression process of the degradable ureteral stent.The parameters of materials,interactions and boundary conditions are set according to the compression environment of the stent for modeling and simulation.On this basis,the friction coefficient of yarns,the yarn radius,and the braided angle of the stent are further compared.The comparison test is carried out by a single variable.The experimental results show that the change of yarn friction coefficient has little influence on the compressive stress,while the yarn radius and the braided angle of the stent have a great influence on the compressive stress. 展开更多
关键词 degradable ureteral stent geometric model compression performance finite element modeling method
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Research and Design of Consistent Project Cases for the Software Engineering Course Group
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作者 Junwei Du Guozhu Liu +3 位作者 Quan Liu Xinglu Ma Meijiao Xu Wenfeng Liu 《计算机教育》 2023年第12期94-105,共12页
In order to enhance the abilities of practical innovation and solving complex engineering problems of students in the engineering context,we design a course cluster teaching model based on a unified enterprise-level p... In order to enhance the abilities of practical innovation and solving complex engineering problems of students in the engineering context,we design a course cluster teaching model based on a unified enterprise-level project case.The program divides the knowledge points required by the project into the corresponding courses,and divides their realization into the practical teaching cases,so as to realize the design of teaching practice cases embodied in the unified project framework.This model allows students to practice projects based on the unified project background while learning knowledge from different courses.It not only allows students to learn abstract,fragmented,and difficult-to-understand knowledge systems thoroughly,but also integrates the knowledge into the practice of the enterprise-level project development,helping students experience the value of knowledge in complex engineering projects and thus improving their ability to solve complex engineering problems while learning theoretical knowledge. 展开更多
关键词 Software engineering Course group Course training Comprehensive project cases School-enterprise cooperation
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Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming
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作者 Zhongyang Wang Youqing Wang Zdzisław Kowalczuk 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期131-140,共10页
In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed metho... In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection. 展开更多
关键词 Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)
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THE LONG TIME BEHAVIOR OF THE FRACTIONAL ORNSTEIN-UHLENBECK PROCESS WITH LINEAR SELF-REPELLING DRIFT
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作者 夏晓宇 闫理坦 杨晴 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期671-685,共15页
Let B^(H) be a fractional Brownian motion with Hurst index 1/2≤H<1.In this paper,we consider the equation(called the Ornstein-Uhlenbeck process with a linear self-repelling drift)dX_(t)^(H)=dB_(t)^(H)+σ X_(t)^(H)... Let B^(H) be a fractional Brownian motion with Hurst index 1/2≤H<1.In this paper,we consider the equation(called the Ornstein-Uhlenbeck process with a linear self-repelling drift)dX_(t)^(H)=dB_(t)^(H)+σ X_(t)^(H)dt+vdt-θ(∫_(0)^(t)(X_(t)^(H)-X_(s)^(H))ds)dt,whereθ<0,σ,v∈ℝ.The process is an analogue of self-attracting diffusion(Cranston,Le Jan.Math Ann,1995,303:87–93).Our main aim is to study the large time behaviors of the process.We show that the solution X^(H)diverges to infinity as t tends to infinity,and obtain the speed at which the process X^(H)diverges to infinity. 展开更多
关键词 fractional Brownian motion stochastic difference equations rate of convergence ASYMPTOTIC
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Set-Membership Filtering Approach to Dynamic Event-Triggered Fault Estimation for a Class of Nonlinear Time-Varying Complex Networks
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作者 Xiaoting Du Lei Zou Maiying Zhong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期638-648,共11页
The present study addresses the problem of fault estimation for a specific class of nonlinear time-varying complex networks,utilizing an unknown-input-observer approach within the framework of dynamic event-triggered ... The present study addresses the problem of fault estimation for a specific class of nonlinear time-varying complex networks,utilizing an unknown-input-observer approach within the framework of dynamic event-triggered mechanism(DETM).In order to optimize communication resource utilization,the DETM is employed to determine whether the current measurement data should be transmitted to the estimator or not.To guarantee a satisfactory estimation performance for the fault signal,an unknown-input-observer-based estimator is constructed to decouple the estimation error dynamics from the influence of fault signals.The aim of this paper is to find the suitable estimator parameters under the effects of DETM such that both the state estimates and fault estimates are confined within two sets of closed ellipsoid domains.The techniques of recursive matrix inequality are applied to derive sufficient conditions for the existence of the desired estimator,ensuring that the specified performance requirements are met under certain conditions.Then,the estimator gains are derived by minimizing the ellipsoid domain in the sense of trace and a recursive estimator parameter design algorithm is then provided.Finally,a numerical example is conducted to demonstrate the effectiveness of the designed estimator. 展开更多
关键词 Dynamic event-triggered mechanism(DETM) fault estimation nonlinear time-varying complex networks set-member-ship filtering unknown input observer
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Intelligent Small Sample Defect Detection of Concrete Surface Using Novel Deep Learning Integrating Improved YOLOv5
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作者 Yongming Han Lei Wang +1 位作者 Youqing Wang Zhiqiang Geng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期545-547,共3页
Dear Editor,This letter presents an intelligent small sample defect detection of concrete surface using novel deep learning integrating the improved YOLOv5 based on the Wasserstein GAN(WGAN)enhancement algorithm.The p... Dear Editor,This letter presents an intelligent small sample defect detection of concrete surface using novel deep learning integrating the improved YOLOv5 based on the Wasserstein GAN(WGAN)enhancement algorithm.The proposed method is capable of producing top-notch data sets to address the issues of insufficient samples and substandard quality. 展开更多
关键词 CONCRETE integrating ALGORITHM
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DeepSVDNet:A Deep Learning-Based Approach for Detecting and Classifying Vision-Threatening Diabetic Retinopathy in Retinal Fundus Images
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作者 Anas Bilal Azhar Imran +4 位作者 Talha Imtiaz Baig Xiaowen Liu Haixia Long Abdulkareem Alzahrani Muhammad Shafiq 《Computer Systems Science & Engineering》 2024年第2期511-528,共18页
Artificial Intelligence(AI)is being increasingly used for diagnosing Vision-Threatening Diabetic Retinopathy(VTDR),which is a leading cause of visual impairment and blindness worldwide.However,previous automated VTDR ... Artificial Intelligence(AI)is being increasingly used for diagnosing Vision-Threatening Diabetic Retinopathy(VTDR),which is a leading cause of visual impairment and blindness worldwide.However,previous automated VTDR detection methods have mainly relied on manual feature extraction and classification,leading to errors.This paper proposes a novel VTDR detection and classification model that combines different models through majority voting.Our proposed methodology involves preprocessing,data augmentation,feature extraction,and classification stages.We use a hybrid convolutional neural network-singular value decomposition(CNN-SVD)model for feature extraction and selection and an improved SVM-RBF with a Decision Tree(DT)and K-Nearest Neighbor(KNN)for classification.We tested our model on the IDRiD dataset and achieved an accuracy of 98.06%,a sensitivity of 83.67%,and a specificity of 100%for DR detection and evaluation tests,respectively.Our proposed approach outperforms baseline techniques and provides a more robust and accurate method for VTDR detection. 展开更多
关键词 Diabetic retinopathy(DR) fundus images(FIs) support vector machine(SVM) medical image analysis convolutional neural networks(CNN) singular value decomposition(SVD) classification
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The first mitogenome of Lauraceae(Cinnamomum chekiangense)
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作者 Changwei Bi Ning Sun +3 位作者 Fuchuan Han Kewang Xu Yong Yang David K.Ferguson 《Plant Diversity》 SCIE CAS CSCD 2024年第1期144-148,共5页
There are three distinct genetic systems in higher plants,the dominant nuclear genome and the semi-autonomous organelle genomes(plastids and mitochondria).In contrast to the conserved plastid genome(plastome),the plan... There are three distinct genetic systems in higher plants,the dominant nuclear genome and the semi-autonomous organelle genomes(plastids and mitochondria).In contrast to the conserved plastid genome(plastome),the plant mitochondrial genome(mitogenome)is characterized by an intriguing“evolutionary paradox”distinguished by a remarkably low mutation rate but with a significantly high rearrangement rate(Palmer and Herbon,1988;Lai et al.,2022). 展开更多
关键词 AUTONOMOUS distinguished Palmer
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Development Method of Wireless Application Based on Wireless Makeup Language and Web Database Technology
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作者 张利 邵世煌 +1 位作者 王建 尹美华 《Journal of Donghua University(English Edition)》 EI CAS 2002年第4期128-131,共4页
Wireless technology is a new emerging delivery networks and development scheme of wireless internet is given widely attention currently. In order to make international visitors to surge education website at any time, ... Wireless technology is a new emerging delivery networks and development scheme of wireless internet is given widely attention currently. In order to make international visitors to surge education website at any time, anywhere by mobile handsets. The communication method of web database, such as CGI, ISAPI, JDBC and so on have been aralyzed and a new Active Server Page &Wireless Makeup Language (ASP-WML) based approach is presented. The dynamical refreshment of the homepage of wireless website and the automatic query of main information have been realized. At last, the wireless website of Dong Hua University is taken as an example to testify the possibility of wireless website design which is mentioned above. 展开更多
关键词 WEB databases WIRELESS application ASP-WML Dynamic SERVICES
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Development of Intelligent Garment Coordination and Virtual Try-on System for Fashion Retailing with RFID Technology
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作者 曾献辉 丁永生 邵世煌 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期127-130,共4页
Improving customer experience has become a more and more important role in enhancing customer service in fashion retailing business. In this study,a kind of intelligent garment coordination and try-on system for fashi... Improving customer experience has become a more and more important role in enhancing customer service in fashion retailing business. In this study,a kind of intelligent garment coordination and try-on system for fashion retailing was proposed. Radio Frequency Identification (RFID) technology was used to identify customer and garment item automatically. The intelligent procedure for garment coordination recommendation using Artificial Neural Network (ANN) was developed to imitate fashion designers' decision-making on garment coordination. Virtual try-on algorithm based on the customer's 2D image was accomplished using image-warping technique. The system architecture and the software framework were also described. The results show that the system is a practical and useful application for fashion retailers. 展开更多
关键词 虚拟企图 服装协作 零卖的时尚 收音机频率鉴定(RFID ) 人工的神经网络(ANN )
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Monitoring and Recognition of Debris Flow Infrasonic Signals 被引量:7
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作者 LIU Dun-long LENG Xiao-peng +2 位作者 WEI Fang-qiang ZHANG Shao-jie HONG Yong 《Journal of Mountain Science》 SCIE CSCD 2015年第4期797-815,共19页
Low frequency infrasonic waves are emitted during the formation and movement of debris flows, which are detectable in a radius of several kilometers, thereby to serve as the precondition for their remote monitoring.Ho... Low frequency infrasonic waves are emitted during the formation and movement of debris flows, which are detectable in a radius of several kilometers, thereby to serve as the precondition for their remote monitoring.However, false message often arises from the simple mechanics of alarms under the ambient noise interference.To improve the accuracy of infrasound monitoring for early-warning against debris flows, it is necessary to analyze the monitor information to identify in them the infrasonic signals characteristic of debris flows.Therefore, a large amount of debris flow infrasound and ambient noises have been collected from different sources for analysis to sum up their frequency spectra, sound pressures, waveforms, time duration and other correlated characteristics so as to specify the key characteristic parameters for different sound sources in completing the development of the recognition system of debris flow infrasonic signals for identifying their possible existence in the monitor signals.The recognition performance of the system has been verified by simulating tests and long-term in-situ monitoring of debris flows in Jiangjia Gully,Dongchuan, China to be of high accuracy and applicability.The recognition system can provide the local government and residents with accurate precautionary information about debris flows in preparation for disaster mitigation and minimizing the loss of life and property. 展开更多
关键词 泥石流灾害 特征识别 监测预警 声信号 识别系统 次声波 运动过程 远程监控
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Vision-based Stabilization of Nonholonomic Mobile Robots by Integrating Sliding-mode Control and Adaptive Approach 被引量:4
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作者 CAO Zhengcai YIN Longjie FU Yili 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期21-28,共8页
Vision-based pose stabilization of nonholonomic mobile robots has received extensive attention.At present,most of the solutions of the problem do not take the robot dynamics into account in the controller design,so th... Vision-based pose stabilization of nonholonomic mobile robots has received extensive attention.At present,most of the solutions of the problem do not take the robot dynamics into account in the controller design,so that these controllers are difficult to realize satisfactory control in practical application.Besides,many of the approaches suffer from the initial speed and torque jump which are not practical in the real world.Considering the kinematics and dynamics,a two-stage visual controller for solving the stabilization problem of a mobile robot is presented,applying the integration of adaptive control,sliding-mode control,and neural dynamics.In the first stage,an adaptive kinematic stabilization controller utilized to generate the command of velocity is developed based on Lyapunov theory.In the second stage,adopting the sliding-mode control approach,a dynamic controller with a variable speed function used to reduce the chattering is designed,which is utilized to generate the command of torque to make the actual velocity of the mobile robot asymptotically reach the desired velocity.Furthermore,to handle the speed and torque jump problems,the neural dynamics model is integrated into the above mentioned controllers.The stability of the proposed control system is analyzed by using Lyapunov theory.Finally,the simulation of the control law is implemented in perturbed case,and the results show that the control scheme can solve the stabilization problem effectively.The proposed control law can solve the speed and torque jump problems,overcome external disturbances,and provide a new solution for the vision-based stabilization of the mobile robot. 展开更多
关键词 非完整移动机器人 视觉控制器 稳定控制器 自适应方法 滑模控制 LYAPUNOV理论 机器人动力学 神经动力学
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Characteristics of nutrients in the Jiulong River and its impact on Xiamen Water, China 被引量:3
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作者 陈宝红 暨卫东 +4 位作者 陈金民 林彩 黄海宁 霍云龙 纪贤标 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1055-1063,共9页
Water samples were collected at 20 sites on 4 occasions in 2009(twice in May,and once in both August and November) along the Jiulong River,South China to examine how nutrient inputs from the Jiulong River could affect... Water samples were collected at 20 sites on 4 occasions in 2009(twice in May,and once in both August and November) along the Jiulong River,South China to examine how nutrient inputs from the Jiulong River could affect the nutrient status of the Xiamen Water.Samples were analyzed for nitrite(NO2-N),nitrate(NO3-N),ammonium(NH4-N),phosphate(PO4-P),silicate(SiO3-Si),salinity,and temperature,to determine the nutrient and trophic status of the river.The results indicate that nutrients are derived mainly from river runoff.NO3-N was the main form of DIN in most parts of the river.In addition,NO3-N,DIN,and SiO3-Si behave conservatively.There is a surplus of DIN and SiO3-Si in the river,and PO4-P is a limitation on phytoplankton growth.The concentration of DIN is typically above 0.60 mg/dm3,and higher than 1.00 mg/dm3in most parts of the river.The concentration of PO4-P is typically above 0.02 mg/dm3,while the concentration of SiO3-Si is higher than 1.00 mg/dm3.Between 2003 and 2008,samples were collected 3 times per year(May,August and November) at 27 sites in the Xiamen Water and analyzed for NO2-N,NO3-N,NH4-N,PO4-P,salinity,and temperature.We discovered that the Jiulong River was the key source of DIN into the Xiamen Water,but not PO4-P,indicating the reason of the N/P molar ratio imbalance in the Xiamen Water.In the future,the effects of high DIN concentrations on the phytoplankton communities and marine ecosystems of the Xiamen Water shall be studied. 展开更多
关键词 营养特性 九龙江 水样 厦门 中国 NO3-N NH4-N 浮游植物生长
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Qualitative Algebra and Graph Theory Methods for Dynamic Trend Analysis of Continuous System 被引量:3
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作者 张卫华 吴重光 王春利 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第2期308-315,共8页
质的代数学的方程是质的模拟的基础,它被用来表示不变的连续过程的动态行为。当质的变量的价值和操作被重新定义时,质的代数学的方程能被转变成签署的直接的图,它经常被用来预言动态变化的趋势。然而,基于人工的尝试使用传统的质的... 质的代数学的方程是质的模拟的基础,它被用来表示不变的连续过程的动态行为。当质的变量的价值和操作被重新定义时,质的代数学的方程能被转变成签署的直接的图,它经常被用来预言动态变化的趋势。然而,基于人工的尝试使用传统的质的代数学方法为动态趋势解决一个复杂问题是困难的。现代质的代数学的一个重要方面是为复杂系统建模并且描绘与相应电脑辅助的自动推理。在这研究,一个质的爱方程基于多重条件被建议,它使签署的直接的图能更好描述复杂系统并且改进差错诊断分辨率。到一个工业盒子的申请证明方法表现很好。 展开更多
关键词 连续系统 代数和 图论 代数方程 图形符号 计算机辅助 定性仿真 动态行为
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