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Deep Structure Optimization for Incremental Hierarchical Fuzzy Systems Using Improved Differential Evolution Algorithm
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作者 Yue Zhu Tao Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1139-1158,共20页
The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) a... The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) and thecorrelation of each sub fuzzy system, the uncertainty of the HFS’s deep structure increases. For the HFS, a largenumber of studies mainly use fixed structures, which cannot be selected automatically. To solve this problem, thispaper proposes a novel approach for constructing the incremental HFS. During system design, the deep structureand the rule base of the HFS are encoded separately. Subsequently, the deep structure is adaptively mutated basedon the fitness value, so as to realize the diversity of deep structures while ensuring reasonable competition amongthe structures. Finally, the differential evolution (DE) is used to optimize the deep structure of HFS and theparameters of antecedent and consequent simultaneously. The simulation results confirm the effectiveness of themodel. Specifically, the root mean square errors in the Laser dataset and Friedman dataset are 0.0395 and 0.0725,respectively with rule counts of rules is 8 and 12, respectively.When compared to alternative methods, the resultsindicate that the proposed method offers improvements in accuracy and rule counts. 展开更多
关键词 Hierarchical fuzzy system automatic optimization differential evolution regression problem
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Research on Automatic Test System of Engine Blade Natural Frequency
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作者 LU Yonghua LIU Jingjing +2 位作者 YANG Haibo HUANG Chuan MA Zhicheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期476-487,共12页
Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequ... Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequency before installing them on the engine to avoid resonance.At present,most blade vibration testing systems require manual operation by operators,which has high requirements for operators and the testing process is also very cumbersome.Therefore,the testing efficiency is low and cannot meet the needs of efficient testing.To solve the current problems of low testing efficiency and high operational requirements,a high-precision and high-efficiency automatic test system is designed.The testing accuracy of this system can reach ±1%,and the testing efficiency is improved by 37% compared to manual testing.Firstly,the influence of compression force and vibration exciter position on natural frequency test is analyzed by amplitude-frequency curve,so as to calibrate servo cylinder and fourdimensional motion platform.Secondly,the sine wave signal is used as the excitation to sweep the blade linearly,and the natural frequency is determined by the amplitude peak in the frequency domain.Finally,the accuracy experiment and efficiency experiment are carried out on the developed test system,whose results verify its high efficiency and high precision. 展开更多
关键词 BLADE vibration failure natural frequency automatic test system
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A Dual Source Power Based EV Wireless Charging System
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作者 NAQVI Syed Zohair Raza XIAO Lan JIANG Menghan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期35-42,共8页
Recently,there has been a huge increase in the usage of fuel resources for automobiles which is severely affecting the climate and causing global warming.The use of electric vehicle(EV)is an effective way to protect t... Recently,there has been a huge increase in the usage of fuel resources for automobiles which is severely affecting the climate and causing global warming.The use of electric vehicle(EV)is an effective way to protect the environment and reduce travel costs.However,the EV charging system has a single charging source,and the charging rate is limited.In this paper,an EV wireless charging system based on dual source power supply has been developed.It realizes intelligent switching between 12 V photovoltaic output and 220 V AC dual source power,and has wireless transmission function.Based on the proposed power supply architecture,the micro wireless charging model is built,which enables the EV model to store power and realize static and mobile control through the wireless induction charging system. 展开更多
关键词 renewable energy inductive coupling inductive charging CONVERTERS automatic changeover auto cutoff circuit
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Design of Fully Automatic Specification Selection System for Resistance Welding Equipment
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作者 Xiangkun Lu Zengtai Tian +1 位作者 Hao Xu Yue Guo 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第1期64-68,共5页
A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding ... A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding of multiple parts on a single machine in automobile factories. The system incorporates an automatic recognition system for different workpiece materials using the added machine fixture,visual detection system for nuts and bolts,and secondary graphical confirmation to ensure the correctness of specification calling. This system achieves reliable,fully automatic selection of welding specifications in resistance welding equipment and has shown significant effects in improving welding quality for massproduced workpieces,while solving the problem of specification calling errors that can occur with traditional methods involving process charts and code adjustments. This system is particularly suitable for promoting applications in manual welding of multiple parts on a single machine in automobile factories,ensuring correct specification calling and welding quality. 展开更多
关键词 seat spot welding welding specifications fully automatic
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Design and Construction of Automatic Monitoring System for Open-pit Coal Mine Slopes
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作者 Yu LUO 《Asian Agricultural Research》 2024年第6期19-21,24,共4页
[Objectives]To monitor the stability of open-pit coal mine slopes in real time and ensure the safety of coal mine production.[Methods]The automatic monitoring system of coal mine slope was explored in depth,and the co... [Objectives]To monitor the stability of open-pit coal mine slopes in real time and ensure the safety of coal mine production.[Methods]The automatic monitoring system of coal mine slope was explored in depth,and the core functions of the system were designed comprehensively.According to the design function of the automatic monitoring system,the slope automatic monitoring system was constructed.Besides,in accordance with the actual situation of the slope,the monitoring frequency of slopes was set scientifically,and the key indicators such as rainfall,deep displacement and surface displacement of the slopes were monitored in an all-round and multi-angle way.[Results]During the monitoring period,the overall condition of the slope remained good,and no landslides or other geological disasters occurred.At the same time,the overall rainfall in the slope area remained low.In terms of monitoring data,the horizontal displacement and settlement of the slopes increased first and then tended to be stable.Specifically,the maximum horizontal displacement during the monitoring period was 22.74 mm,while the maximum settlement was 18.65 mm.[Conclusions]The automatic slope monitoring system has obtained remarkable achievements in practical application.It not only improves the accuracy and efficiency of slope stability monitoring,but also provides valuable reference experience for similar projects. 展开更多
关键词 SLOPE MONITORING Automatic MONITORING technology Global Navigation Satellite system (GNSS) MONITORING system EARLY WARNING
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Automatic Monitoring System for 3-D Deformation of Crustal Fault Based on Laser and Machine Vision
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作者 Qingshan Wang Guoying Su +3 位作者 Qingzun Ma Haiquan Yin Zhihang Liu Chuanzhen Lv 《Instrumentation》 2024年第2期44-52,共9页
An automatic monitoring method of the 3-D deformation is presented for crustal fault based on laser and machine vision. The laser source and screen are independently set up in the headwall and footwall, the collimated... An automatic monitoring method of the 3-D deformation is presented for crustal fault based on laser and machine vision. The laser source and screen are independently set up in the headwall and footwall, the collimated laser beam creates a circular spot on the screen, meanwhile, the industrial camera captures the tiny deformation of the crustal fault by monitoring the change of the spot position. This method significantly reduces the cost of equipment and labor, provides daily sampling to ensure high continuity of data. A prototype of the automatic monitoring system is developed, and a repeatability test indicates that the error of spot jitter can be minimized by consecutive samples. Meanwhile, the environmental correction model is determined to ensure that environmental changes do not disturb the system. Furthermore, the automatic monitoring system has been applied at the deformation monitoring station(KJX02) of China Beishan underground research laboratory, where continuous deformation monitoring is underway. 展开更多
关键词 deformation measurement crustal fault automatic monitoring laser spot machine vision
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Design of Intelligent Window Automatic Monitoring System Based on Microcontroller Control
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作者 Liyan Gao Rongfang Zong 《Journal of Electronic Research and Application》 2024年第4期34-40,共7页
To ensure the safety of residents’lives and property by using automatic opening and closing of ordinary windows,this article designs an intelligent window automatic monitoring system.The article proposes a software a... To ensure the safety of residents’lives and property by using automatic opening and closing of ordinary windows,this article designs an intelligent window automatic monitoring system.The article proposes a software and hardware design scheme for the system,which comprises a microcontroller control module,temperature and humidity detection module,harmful gas detection module,rainfall detection module,human thermal radiation induction module,Organic Light-Emitting Diode(OLED)display module,stepper motor drive module,Wi-Fi communication module,etc.Users use this system to monitor environmental data such as temperature,humidity,rainfall,harmful gas concentrations,and human health.Users can control the opening and closing of windows through manual,microcontroller,and mobile application(app)remote methods,providing users with a more convenient,comfortable,and safe living environment. 展开更多
关键词 Smart window Automatic monitoring STM32 microcontroller Mobile application
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Neural Network-Powered License Plate Recognition System Design
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作者 Sakib Hasan Md Nagib Mahfuz Sunny +1 位作者 Abdullah Al Nahian Mohammad Yasin 《Engineering(科研)》 2024年第9期284-300,共17页
The development of scientific inquiry and research has yielded numerous benefits in the realm of intelligent traffic control systems, particularly in the realm of automatic license plate recognition for vehicles. The ... The development of scientific inquiry and research has yielded numerous benefits in the realm of intelligent traffic control systems, particularly in the realm of automatic license plate recognition for vehicles. The design of license plate recognition algorithms has undergone digitalization through the utilization of neural networks. In contemporary times, there is a growing demand for vehicle surveillance due to the need for efficient vehicle processing and traffic management. The design, development, and implementation of a license plate recognition system hold significant social, economic, and academic importance. The study aims to present contemporary methodologies and empirical findings pertaining to automated license plate recognition. The primary focus of the automatic license plate recognition algorithm was on image extraction, character segmentation, and recognition. The task of character segmentation has been identified as the most challenging function based on my observations. The license plate recognition project that we designed demonstrated the effectiveness of this method across various observed conditions. Particularly in low-light environments, such as during periods of limited illumination or inclement weather characterized by precipitation. The method has been subjected to testing using a sample size of fifty images, resulting in a 100% accuracy rate. The findings of this study demonstrate the project’s ability to effectively determine the optimal outcomes of simulations. 展开更多
关键词 Intelligent Traffic Control systems Automatic License Plate Recognition (ALPR) Neural Networks Vehicle Surveillance Traffic Management License Plate Recognition Algorithms Image Extraction Character Segmentation Character Recognition Low-Light Environments Inclement Weather Empirical Findings Algorithm Accuracy Simulation Outcomes DIGITALIZATION
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Design and implementation of digital closed-loop drive control system of a MEMS gyroscope 被引量:5
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作者 王晓雷 李宏生 杨波 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期35-40,共6页
In order to effectively control the working state of the gyroscope in drive mode, the drive characteristics of the micro electromechanical system (MEMS) gyroscope are analyzed in principle. A novel drive circuit for... In order to effectively control the working state of the gyroscope in drive mode, the drive characteristics of the micro electromechanical system (MEMS) gyroscope are analyzed in principle. A novel drive circuit for the MEMS gyroscope in digital closed-loop control is proposed, which utilizes a digital phase-locked loop (PLL) in frequency control and an automatic gain control (AGC) method in amplitude control. A digital processing circuit with a field programmable gate array (FPGA) is designed and the experiments are carried out. The results indicate that when the temperature changes, the drive frequency can automatically track the resonant frequency of gyroscope in drive mode and that of the oscillating amplitude holds at a set value. And at room temperature, the relative deviation of the drive frequency is 0.624 ×10^-6 and the oscillating amplitude is 8.0 ×10^-6, which are 0. 094% and 18. 39% of the analog control program, respectively. Therefore, the control solution of the digital PLL in frequency and the AGC in amplitude is feasible. 展开更多
关键词 micro electromechanical system (MEMS) digitalgyroscope drive frequency phase-locked loop (PLL) oscillating amplitude automatic gain control (AGC)
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Application of Automatic Water-saving Irrigation System in Roof Gardens 被引量:1
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作者 周炼 张美 《Journal of Landscape Research》 2009年第4期75-79,共5页
Based on the special site conditions of roof gardens,it was put forward to introduce automatic water-saving irrigation system into the roof garden constructions,such as the solar energy and microcomputer auto water-sa... Based on the special site conditions of roof gardens,it was put forward to introduce automatic water-saving irrigation system into the roof garden constructions,such as the solar energy and microcomputer auto water-saving irrigation system,aiming to solve the photosynthetic noon break phenomenon of plants and relieve the stress from high temperature. 展开更多
关键词 AUTOMATIC IRRIGATION WATER-SAVING IRRIGATION ROOF GARDEN
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On-Board Data Acquisition System for Automatic Shift System of Vehicle
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作者 席军强 陈慧岩 +1 位作者 丁华荣 窦建革 《Journal of Beijing Institute of Technology》 EI CAS 2001年第4期436-442,共7页
Data acquisition, analysis and calibrating system affiliated with the vehicle is developed for the research on the automatic shift system (ASS). Considering the vehicle’s hard environment such as vibration, high and ... Data acquisition, analysis and calibrating system affiliated with the vehicle is developed for the research on the automatic shift system (ASS). Considering the vehicle’s hard environment such as vibration, high and low temperature, electromagnetic disturbance and so on, the most suitable project is selected. PC104 transfers data with ECU by serial communication and a solid state disk is used as a FLASH ROM. Some techniques including frequency division of data is adopted in the software design in order to ensure the sampling frequency. The analysis and debug software is also contrived according to the characteristic of the ASS. The system plays an important role in the development of the ASS because of the good reliability and practicability in the application. 展开更多
关键词 automatic shift system data acquisition serial communication
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Design and Application of Automatic Test System of Soil Water Characteristic Curve
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作者 唐玉邦 徐磊 +3 位作者 虞利俊 裴勤 王恒义 黄万喜 《Agricultural Science & Technology》 CAS 2014年第11期2026-2029,共4页
[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic c... [Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic curve was designed by combining the conceptions of soil moisture content and soil water potential. [Method] Electronic soil moisture tension meter was used to determine the real-time tension value of soil moisture in the tested container, and the electronic Weigh sensor was used to determine soil Weigh. Minusing method was used to calculate soil moisture content, based on which the soil water characteristic curve was plotted. [Result] Through the filed survey of 2 different kinds of soil in Jiangsu Province, the results were as fol ows: soil of different composition showed different trend in soil water characteristic curve that the soil water characteristic relation of the sandy soil in the old course of the Yel ow River in Xuzhou was Y=-0.000 2X3+0.027 7X2-1.644 5X+38.161, R2=0.991 9; while the soil water characteristic relation of the saline-alkali soil in Jinhai Farm of Dafeng was Y=-0.00 2X2-0.426X+39.905, R2=0.991 3. [Con-clusion] The automatic test system of soil water characteristic curve soil water char-acteristics curve could reflect soil moisture content and soil water potential, as wel as reflect the effectiveness of soil water to plant growth, providing basis for the sci-entific irrigation. 展开更多
关键词 Soil water characteristics curve Water tension meter Automatic detec-tion Wireless charging
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Reflections on the Automated Essay Scoring System of English Writing in Vocational Colleges
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作者 李恩亮 《疯狂英语(理论版)》 2018年第4期29-30,共2页
English Teaching in higher vocational colleges emphasizes the principle of "practical use and adequate sufficiency". English courses should not only lay a good foundation for language, but also pay more atte... English Teaching in higher vocational colleges emphasizes the principle of "practical use and adequate sufficiency". English courses should not only lay a good foundation for language, but also pay more attention to the training of practical language skills, especially the ability to use English to deal with daily and foreign business activities. Higher vocational college students who are relatively weak in their basic English writing are particularly prominent,far from the regulated requirements. Because of the poor basic learning ability of higher vocational college students, it is very important for teachers to supervise and get feedback. But the ratio of students to English teachers in some higher vocational colleges has reached 130 : 1, so it is becoming more and more important for teachers to adopt computer aided correction composition system. 展开更多
关键词 higher VOCATIONAL COLLEGE English WRITING automatic composition SCORE
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An Insect Imaging System to Automate Rice Light-Trap Pest Identification 被引量:23
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作者 YAO Qing LV Jun +4 位作者 LIU Qing-jie DIAO Guang-qiang YANG Bao-jun CHEN Hong-ming TANGJian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第6期978-985,共8页
Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and ... Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and leads to fatigue and an increase in the error rate. A rice light-trap insect imaging system is developed to automate rice pest identification. This system can capture the top and bottom images of each insect by two cameras to obtain more image features. A method is proposed for removing the background by color difference of two images with pests and non-pests. 156 features including color, shape and texture features of each pest are extracted into an support vector machine (SVM) classifier with radial basis kernel function. The seven-fold cross-validation is used to improve the accurate rate of pest identification. Four species of Lepidoptera rice pests are tested and achieved 97.5% average accurate rate. 展开更多
关键词 automatic identification imaging system rice light-trap pests SVM cross-validate
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Design and dynamic simulation of hydraulic system of a new automatic transmission 被引量:15
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作者 王书翰 徐向阳 +3 位作者 刘艳芳 戴振坤 TEN BERGE P 曲巍 《Journal of Central South University》 SCIE EI CAS 2009年第4期697-701,共5页
A new hydraulic system of a novel automatic transmission (AT) was designed. The dimension and structure of valves and cylinders were designed by theoretical calculation. The dynamic simulation model of hydraulic syste... A new hydraulic system of a novel automatic transmission (AT) was designed. The dimension and structure of valves and cylinders were designed by theoretical calculation. The dynamic simulation model of hydraulic system of AT was established by ITI-SimulationX. Simulation results and theoretical design results were compared to confirm the simulation model. Based on the confirmed simulation model, the simulation results of pressure and flow of the hydraulic system were analyzed. The dynamic simulation method is very helpful for designing and analyzing the performance of hydraulic system and further optimization design. The theoretical design method and dynamic simulation model are feasible for the real industrial applications. The research results can be used in hydraulic system design and optimization. 展开更多
关键词 automatic transmission hydraulic system dynamic simulation
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Development of an automatic monitoring system for rice light-trap pests based on machine vision 被引量:15
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作者 YAO Qing FENG Jin +9 位作者 TANG Jian XU Wei-gen ZHU Xu-hua YANG Bao-jun LU Jun XIE Yi-ze YAO Bo WU Shu-zhen KUAI Nai-yang WANG Li-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第10期2500-2513,共14页
Monitring pest populations in paddy fields is important to effectively implement integrated pest management.Light traps are widely used to monitor field pests all over the world.Most conventional light traps still inv... Monitring pest populations in paddy fields is important to effectively implement integrated pest management.Light traps are widely used to monitor field pests all over the world.Most conventional light traps still involve manual identification of target pests from lots of trapped insects,which is time-consuming,labor-intensive and error-prone,especially in pest peak periods.In this paper,we developed an automatic monitoring system for rice light-trap pests based on machine vision.This system is composed of an itelligent light trap,a computer or mobile phone client platform and a cloud server.The light trap firstly traps,kills and disperses insects,then collects images of trapped insects and sends each image to the cloud server.Five target pests in images are automatically identifed and counted by pest identification models loaded in the server.To avoid light-trap insects piling up,a vibration plate and a moving rotation conveyor belt are adopted to disperse these trapped insects.There was a close correlation(r=0.92)between our automatic and manual identification methods based on the daily pest number of one-year images from one light trap.Field experiments demonstrated the effectiveness and accuracy of our automatic light trap monitoring system. 展开更多
关键词 automatic monitoring system light trap rice pest machine vision image processing convolutional neural network
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Fault diagnosis for down-hole conditions of sucker rod pumping systems based on the FBH-SC method 被引量:9
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作者 Kun Li Xian-Wen Gao +1 位作者 Hai-Bo Zhou Ying Han 《Petroleum Science》 SCIE CAS CSCD 2015年第1期135-147,共13页
Dynamometer cards are commonly used to analyze down-hole working conditions of pumping systems in actual oil production. Nowadays, the traditional supervised learning methods heavily rely on the classification accurac... Dynamometer cards are commonly used to analyze down-hole working conditions of pumping systems in actual oil production. Nowadays, the traditional supervised learning methods heavily rely on the classification accuracy of the training samples. In order to reduce the errors of manual classification, an automatic clustering algorithm is proposed and applied to diagnose down-hole conditions of pumping systems. The spectral clustering (SC) is a new clustering algorithm, which is suitable for any data distribution. However, it is sensitive to initial cluster centers and scale parameters, and needs to predefine the cluster number. In order to overcome these shortcom- ings, we propose an automatic clustering algorithm, fast black hole-spectral clustering (FBH-SC). The FBH algo- rithm is used to replace the K-mean method in SC, and a CritC index function is used as the target function to automatically choose the best scale parameter and clus- tering number in the clustering process. Different simulation experiments were designed to define the relationship among scale parameter, clustering number, CritC index value, and clustering accuracy. Finally, an example is given to validate the effectiveness of the proposed algorithm. 展开更多
关键词 Sucker rod pumping systems Fault diagnosis Spectral clustering Automatic clustering Fast black hole algorithm
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Improved Smith prediction monitoring AGC system based on feedback-assisted iterative learning control 被引量:4
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作者 张浩宇 孙杰 +2 位作者 张殿华 陈树宗 张欣 《Journal of Central South University》 SCIE EI CAS 2014年第9期3492-3497,共6页
The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning co... The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning control strategy, which learned unknown modeling error by using previous control information repeatedly, was introduced into Smith prediction monitoring AGC system. Firstly, conventional Smith predictor and improved Smith predictor with PI-P controller were analyzed. Secondly, on the basis of establishing of feedback-assisted iterative learning control strategy for improved Smith predictor, process control signal update law and control error were deduced, then convergence condition of this strategy was put forward and proved. Finally, after modeling the automatic position control system, the PI-P Smith prediction monitoring AGC system with feedback-assisted iterative learning control was researched through simulation. Simulation results indicate that this system remains stable during model mismatching. The robustness and response of monitoring AGC is improved by development of feedback-assisted iterative learning control strategy for PI-P Smith predictor. 展开更多
关键词 automatic gauge control Smith predictor monitoring automatic gauge control (AGC) feedback-assisted iterativelearning control automatic position control
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Integrated Virtual Assembly Process Planning System 被引量:5
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作者 LIU Jianhua HOU Weiwei SHANG Wei NING Ruxin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期717-728,共12页
Assembly process planning(APP) for complicated products is a time-consuming and difficult work with conventional method. Virtual assembly process planning(VAPP) provides engineers a new and efficiency way. Previou... Assembly process planning(APP) for complicated products is a time-consuming and difficult work with conventional method. Virtual assembly process planning(VAPP) provides engineers a new and efficiency way. Previous studies in VAPP are almost isolated and dispersive, and have not established a whole understanding and discussed key realization techniques of VAPP from a systemic and integrated view. The integrated virtual assembly process planning(IVAPP) system is a new virtual reality based engineering application, which offers engineers an efficient, intuitive, immersive and integrated method for assembly process planning in a virtual environment. Based on analysis the information integration requirement of VAPP, the architecture of IVAPP is proposed. Through the integrated structure, IVAPP system can realize information integration and workflow controlling. In order to mode/the assembly process in IVAPP, a hierarchical assembly task list(HATL) is presented, in which different assembly tasks for assembling different components are organized into a hierarchical list. A process-oriented automatic geometrical constraint recognition algorithm(AGCR) is proposed, so that geometrical constraints between components can be automatically recognized during the process of interactive assembling. At the same time, a progressive hierarchical reasoning(PHR) model is discussed. AGCR and PHR will greatly reduce the interactive workload. A discrete control node model(DCNM) for cable harness assembly planning in IVAPP is detailed. DCNM converts a cable harness into continuous flexed line segments connected by a series of section center points, and designs can realize cable harness planning through controlling those control nodes. Mechanical assemblies (such as transmission case and engine of automobile) are used to illustrate the feasibility of the proposed method and algorithms. The application of IVAPP system reveals advantages over the traditional assembly process planning method in shortening the time-consumed in assembly planning and in minimizing the handling difficulty, excessive reorientation and dissimilarity of assembly operations. 展开更多
关键词 virtual assembly assembly model assembly task collision detection automatic constraint recognition cable harness assembly process planning
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Investigation of Knowledge Transfer Approaches to Improve the Acoustic Modeling of Vietnamese ASR System 被引量:5
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作者 Danyang Liu Ji Xu +1 位作者 Pengyuan Zhang Yonghong Yan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1187-1195,共9页
It is well known that automatic speech recognition(ASR) is a resource consuming task. It takes sufficient amount of data to train a state-of-the-art deep neural network acoustic model. As for some low-resource languag... It is well known that automatic speech recognition(ASR) is a resource consuming task. It takes sufficient amount of data to train a state-of-the-art deep neural network acoustic model. As for some low-resource languages where scripted speech is difficult to obtain, data sparsity is the main problem that limits the performance of speech recognition system. In this paper, several knowledge transfer methods are investigated to overcome the data sparsity problem with the help of high-resource languages.The first one is a pre-training and fine-tuning(PT/FT) method, in which the parameters of hidden layers are initialized with a welltrained neural network. Secondly, the progressive neural networks(Prognets) are investigated. With the help of lateral connections in the network architecture, Prognets are immune to forgetting effect and superior in knowledge transferring. Finally,bottleneck features(BNF) are extracted using cross-lingual deep neural networks and serves as an enhanced feature to improve the performance of ASR system. Experiments are conducted in a low-resource Vietnamese dataset. The results show that all three methods yield significant gains over the baseline system, and the Prognets acoustic model performs the best. Further improvements can be obtained by combining the Prognets model and bottleneck features. 展开更多
关键词 BOTTLENECK feature (BNF) cross-lingual automatic speech recognition (ASR) PROGRESSIVE neural networks (Prognets) model transfer learning
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