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Aircraft Observation and Simulation of the Supercooled Liquid Water Layer in a Warm Conveyor Belt over North China
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作者 Jiefan YANG Fei YAN +3 位作者 Hengchi LEI Shuo JIA Xiaobo DONG Xiangfeng HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期529-544,共16页
This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer... This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft observation.Although the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics schemes.The conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water layer.However,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin scheme.To reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics. 展开更多
关键词 warm conveyor belt Microphysical properties supercooled liquid water microphysics schemes
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Oil-Film Clutch in Soft-Start of Belt Conveyor 被引量:3
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作者 周满山 魏宸官 +1 位作者 于岩 张媛 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期142-145,共4页
The oil film clutch, which is superior in speed adjustment, is capable of being used in the belt conveyor to carry out soft start operation. According to running properties of both belt conveyor and oil film clutch... The oil film clutch, which is superior in speed adjustment, is capable of being used in the belt conveyor to carry out soft start operation. According to running properties of both belt conveyor and oil film clutch, equations that are used to decide the lubricating oil flow and the number of oil films (i.e. the number of rotating and stationary plates) are deduced theoretically. Also key parameters are provided for the design of the hydraulic system. All these together provide the theoretical basis for the soft start design of the belt conveyor and references for the application of the oil film clutch in similar fields. 展开更多
关键词 belt conveyor soft start oil film clutch lubricating theory
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KEY TECHNOLOGY OF SEMI-CONTINOUS CONVEYOR SYSTEM IN DEEP SURFACE MINE
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作者 苏靖 刘胜富 任天贵 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1996年第2期102+99-102,共5页
The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of co... The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of conveyor system are studied, and their calculating models are built up. 展开更多
关键词 surface mine semi-continous conveyor system key technology
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Research on Dynamic Tension for Belt Conveyor with Constant Force Automatic Take-Up Assembly
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作者 孟国营 陈京丽 李玉瑾 《Journal of China University of Mining and Technology》 2003年第2期187-191,共5页
The article Provides a dynamic model for belt conveyor. Based on the drive-force of conveyor, take-up tension of take-up assembly, gravity of conveyor belt and material, and friction between belt and idlers, it gives ... The article Provides a dynamic model for belt conveyor. Based on the drive-force of conveyor, take-up tension of take-up assembly, gravity of conveyor belt and material, and friction between belt and idlers, it gives a viscoelastic dynamic equation for conveyor belt. It presents a calculation method of analytic solution to both viscoelastic dynamic equation and geometric dynamic equation when automatic take-up assembly is applied to belt conveyor. The article also makes a study of design method of limiting and eliminating the conveyor belt's elastic vibration. 展开更多
关键词 belt conveyor dynamic equation displacement calculation conveyor belt tension calculation limiting vibration impact
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Research on Vibration Characteristics of Large Scale Belt Conveyor and Its Application
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作者 Gao Yang 《International Journal of Technology Management》 2014年第8期24-26,共3页
High speed and large capacity belt conveyor is the main development trend. In the design, calculated and used of belt conveyor must be considered the high speed, large capacity, dynamic load. This paper starts from th... High speed and large capacity belt conveyor is the main development trend. In the design, calculated and used of belt conveyor must be considered the high speed, large capacity, dynamic load. This paper starts from the analysis of conveyor belt transverse vibration. Through calculate transverse vibration natural frequency of conveyor belt, and analyze the lateral stability of belt conveyor. 展开更多
关键词 Belt conveyor conveyor belt vibration characteristics control method
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Fuzzy-immune control strategy of a hydro-viscous soft start device of a belt conveyor 被引量:6
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作者 XIE Fang-wei HOU You-fu +1 位作者 XU Zhi-peng ZHAO Rui 《Mining Science and Technology》 EI CAS 2009年第4期544-548,共5页
Considering the control difficulties of a hydro-viscous trol algorithm was derived. A fuzzy-immune PID controller was soft start (HVSS) device of a belt conveyor, a fuzzy-immune con- designed based on immune feedbac... Considering the control difficulties of a hydro-viscous trol algorithm was derived. A fuzzy-immune PID controller was soft start (HVSS) device of a belt conveyor, a fuzzy-immune con- designed based on immune feedback regulations and adaptability of the fuzzy logic inference. Using MATLAB software, we simulated the controller and compared the HVSS device with a conven- tional PID controller and a fuzzy PID controller. The simulation results show that the controller is not only very reliable as a PID controller, robust and requires only a short adjustment time of fuzzy control, but possesses also capacity of global optimization of the immune algorithm. To verify our theoretical analysis and simulation, a HVSS test-bed was developed. The experimental results demonstrate that the fuzzy-immune PID controller managed to start the belt conveyor softly and to follow an S-shaped curve while the output speed correctly followed the preset speed with only small fluctuations in speed. 展开更多
关键词 fuzzy-immune hydro-viscous soft-start control strategy belt conveyor PID
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Mechanism of hydro-viscous soft start of belt conveyor 被引量:9
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作者 MENG Qing-rui HOU You-fu 《Journal of China University of Mining and Technology》 EI 2008年第3期459-465,共7页
The mechanism of a hydro-viscous soft start is of great importance in the design of a hydro-viscous clutch and its control system. To explain the mechanism of a hydro-viscous soft start, the startup process of a belt ... The mechanism of a hydro-viscous soft start is of great importance in the design of a hydro-viscous clutch and its control system. To explain the mechanism of a hydro-viscous soft start, the startup process of a belt conveyor was numerically analyzed with the modified Reynolds equation, an energy equation and a temperature-viscosity equation. The effect of temperature and grooves of the friction disk surface on torque transfer and load capacity of the oil film have also been analyzed. The results show that 1) the grooves are the basis of forming dynamic pressure but they may reduce the capacity of torque transfer to a certain extent, 2) during the startup process, temperature has little effect on torque transfer and load capacity and the variation in load capacity of the oil film is very small, indicating that it is preferable to use the flow rate as a control object than the pressure of the feed cylinder. The results have been verified by an experiment. 展开更多
关键词 hydro-viscous clutch soft start belt conveyor torque transfer load capacity
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Dynamic characteristics of conveyor belts 被引量:8
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作者 HOU You-fu MENG Qing-mi 《Journal of China University of Mining and Technology》 EI 2008年第4期629-633,共5页
The dynamic characteristics of a belt conveyor are determined to a large extent by the properties of the belt. This paper describes experiments designed to establish the dynamic properties of belting material. The dyn... The dynamic characteristics of a belt conveyor are determined to a large extent by the properties of the belt. This paper describes experiments designed to establish the dynamic properties of belting material. The dynamic elastic modulus, viscous damping and rheologicat constants of the belt were measured. Several properties were studied as a function of the tensile loading on the belt. These included longitudinal vibration, the natural vibration frequency in the transverse direction and the response to an impulse excitation. Vibration response was observed under several different excitation frequencies. Most of these properties have not been tested previously under conditions appropriate for the ISO/DP9856 standard. Two types of belt were tested, a steel reinforced belt and a fabric reinforced belt. The test equipment was built to provide data appropriate for designing belt conveyors. It was observed that the stress wave propagation speed increased with tensile load and that tensile load was the main factor influencing longitudinal vibrations. 展开更多
关键词 experimental investigation dynamic characteristics conveyor belt
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Virtual straightening of scraper conveyor based on the position and attitude solution of industrial robot model 被引量:3
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作者 Suhua Li Jiacheng Xie +3 位作者 Fang Ren Xin Zhang Xuewen Wang Binbin Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第5期1149-1170,共22页
The movement of the floating connecting mechanism between a hydraulic support and scraper conveyor is space movement;thus,when the hydraulic support pushes the scraper conveyor,there is an error between the actual dis... The movement of the floating connecting mechanism between a hydraulic support and scraper conveyor is space movement;thus,when the hydraulic support pushes the scraper conveyor,there is an error between the actual distance of the scraper conveyor and the theoretical moving distance.As a result,the scraper conveyor cannot obtain the straightness requirement.Therefore,the movement law of the floating connecting mechanism between the hydraulic support and scraper conveyor is analyzed and programmed into the Unity3D to realize accurate pushing of the scraper conveyor via hydraulic support.The Coal Seam?Equipment Joint Virtual Straightening System is established,and a straightening method based on the motion law of a floating connection is proposed as the default method of the system.In addition,a straightening simulation of the scraper conveyor was performed on a complex coal seam floor,the results demonstrate that the average straightening error of the scraper conveyor is within 2-8 mm,and is in direct proportion to the fluctuation of the coal seam floor in the strike of the seam with high accuracy,the straightness of scraper conveyor is more affected by the subsidence terrain during straightening than by the bulge terrain.And some conclusions are verified by experiment.Based on the verification of the relevant conclusions,a comparison and analysis of Longwall Automation Steering Committee(LASC)straightening technology and default straightening method in the simulation system shows that the straightness accuracy of LASC straightening technology under complex floor conditions is slightly less than that of the default straightening method in the proposed system. 展开更多
关键词 Virtual reality Scraper conveyor Hydraulic support Posture solution Straightness control
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Theoretical research on hydroviscous speed-adjusting clutch in soft-start of belt conveyor 被引量:4
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作者 周满山 张媛 《Journal of Coal Science & Engineering(China)》 2005年第1期79-82,共4页
Through research on the application of hydroviscous speed-adjusting clutch in belt conveyor, this paper concluded that hydroviscous speed-adjusting clutch has many advantages such as controllable start and stop, overl... Through research on the application of hydroviscous speed-adjusting clutch in belt conveyor, this paper concluded that hydroviscous speed-adjusting clutch has many advantages such as controllable start and stop, overload protection and multi-motor power equilibrium. But its theory when used in large power fan and pump could not meet the needs of belt conveyor soft-start operation. Focusing on the theo- retical analysis of the lubrication oil flow needed by the transmission procedure to form the oil-film. Put forward concrete calculation methods of lubrication flow and how to de- cide number of oil-films used in belt conveyor. 展开更多
关键词 belt conveyor hydroviscous speed-adjusting clutch soft-start lubrication theory
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Second generation fully differential current conveyor based analog circuits 被引量:1
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作者 A.Tonk N.Afzal 《Journal of Semiconductors》 EI CAS CSCD 2019年第4期23-28,共6页
In this paper, we present a new voltage-mode biquad filter that uses a six-terminal CMOS fully differential current conveyor(FDCCII). The FDCCII with only 23 transistors in its structure and operating at ± 1.5 V,... In this paper, we present a new voltage-mode biquad filter that uses a six-terminal CMOS fully differential current conveyor(FDCCII). The FDCCII with only 23 transistors in its structure and operating at ± 1.5 V, is based on a class AB fully differential buffer. The proposed filter has the facility to tune gain, ωo and Q. A circuit division circuit(CDC) is employed to digitally control the FDCCII block. This digitally controlled FDCCII is used to realize a new reconfigurable fully-differential integrator and differentiator. We performed SPICE simulations to determine the performance of all circuits using CMOS 0.25 μm technology. 展开更多
关键词 CURRENT conveyors fully DIFFERENTIAL digitally CONTROLLED INTEGRATOR DIFFERENTIATOR
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ROLE OF A WARM AND WET TRANSPORT CONVEYOR OF ASIAN SUMMER MONSOON IN A BEIJING HEAVY RAINSTORM ON JULY 21,2012 被引量:2
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作者 LIU Yan-ju DING Yi-hui +1 位作者 ZHANG Ying-xian SONG Ya-fang 《Journal of Tropical Meteorology》 SCIE 2017年第3期302-313,共12页
A heavy rainstorm named Beijing "7.21"heavy rainstorm hit Beijing on 21 to 22 July 2012, which is recorded as the most severe rainstorm since 1951. The daily precipitation amount in many stations in Beijing ... A heavy rainstorm named Beijing "7.21"heavy rainstorm hit Beijing on 21 to 22 July 2012, which is recorded as the most severe rainstorm since 1951. The daily precipitation amount in many stations in Beijing has broken the history record. Based on the NCAR/NCEP reanalysis data and precipitation observation,the large-scale conditions which caused the "7.21"heavy rainstorm are investigated, with the emphasis on the relationship between it and an equatorial convergence zone, Asian summer monsoon as well as the tropical cyclone over the ocean from the Philippines to the South China Sea(SCS). The results indicated that a great deal of southerly warm and wet moisture carried by northward migrating Asian summer monsoon provided plenty of moisture supplying for the "7.21"heavy rainstorm. When the warm and wet moisture met with the strong cold temperature advection induced by cold troughs or vortexes, an obviously unstable stratification formed, thus leading to the occurrence of heavy precipitation. Without this kind of intense moisture transport, the rainstorm only relying on the role of the cold air from mid-and higher-latitudes could not reach the record-breaking intensity. Further research suggested that the northward movement of an Asian monsoonal warm and wet moisture transport conveyor(MWWTC) was closely related with the active phase of a 30-60 day intra-seasonal oscillation of the Asian summer monsoon. During this time, the monsoon surge triggered and maintained the northward movement of the MWWTC. In addition, compared with another heavy rainstorm named"63.8"heavy rainstorm, which occurred over the Huaihe River Basin in the mid-August 1963 and seriously affected North China, a similar MWWTC was also observed. It was just the intense interaction of the MWWTC with strong cold air from the north that caused this severe rainstorm. 展开更多
关键词 Beijing "7.1" heavy rainstorm Asian summer monsoon warm and wet transport conveyor
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Conveyor-Belt Detection of Conditional Deep Convolutional Generative Adversarial Network 被引量:2
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作者 Xiaoli Hao Xiaojuan Meng +2 位作者 Yueqin Zhang JinDong Xue Jinyue Xia 《Computers, Materials & Continua》 SCIE EI 2021年第11期2671-2685,共15页
In underground mining,the belt is a critical component,as its state directly affects the safe and stable operation of the conveyor.Most of the existing non-contact detection methods based on machine vision can only de... In underground mining,the belt is a critical component,as its state directly affects the safe and stable operation of the conveyor.Most of the existing non-contact detection methods based on machine vision can only detect a single type of damage and they require pre-processing operations.This tends to cause a large amount of calculation and low detection precision.To solve these problems,in the work described in this paper a belt tear detection method based on a multi-class conditional deep convolutional generative adversarial network(CDCGAN)was designed.In the traditional DCGAN,the image generated by the generator has a certain degree of randomness.Here,a small number of labeled belt images are taken as conditions and added them to the generator and discriminator,so the generator can generate images with the characteristics of belt damage under the aforementioned conditions.Moreover,because the discriminator cannot identify multiple types of damage,the multi-class softmax function is used as the output function of the discriminator to output a vector of class probabilities,and it can accurately classify cracks,scratches,and tears.To avoid the features learned incompletely,skiplayer connection is adopted in the generator and discriminator.This not only can minimize the loss of features,but also improves the convergence speed.Compared with other algorithms,experimental results show that the loss value of the generator and discriminator is the least.Moreover,its convergence speed is faster,and the mean average precision of the proposed algorithm is up to 96.2%,which is at least 6%higher than that of other algorithms. 展开更多
关键词 Multi-class detection conditional deep convolution generative adversarial network conveyor belt tear skip-layer connection
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MISO-Type Voltage-Mode Universal Biquadratic Filter Using Single Universal Voltage Conveyor 被引量:2
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作者 Kanhaiya Lal Pushkar Kavya Gupta 《Circuits and Systems》 2017年第9期227-236,共10页
A universal biquadratic filter using single universal voltage conveyor (UVC), two resistors and two capacitors is presented in this paper. The proposed structure has three inputs and one output and can realize all the... A universal biquadratic filter using single universal voltage conveyor (UVC), two resistors and two capacitors is presented in this paper. The proposed structure has three inputs and one output and can realize all the five standard biquadratic filters: low-pass (LP), high-pass (HP), band-pass (BP), band-reject (BR) and all-pass (AP) from the same circuit configuration. The presented universal filter offers low active and passive sensitivities. SPICE (Version 16.5) simulation results using 0.18 μm TSMC technology have been included. 展开更多
关键词 UNIVERSAL VOLTAGE conveyor VOLTAGE-MODE Filter ANALOG Circuit Design
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Theoretical and experimental investigation on optimization of a non-contact air conveyor 被引量:1
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作者 钟伟 黎鑫 +2 位作者 陶国良 路波 香川利春 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期353-361,共9页
Air film conveyors equipped with porous pads have been developed to bring the liquid crystal display(LCD) into a non-contact state during transportation process. In this work, a theoretical model including flow proper... Air film conveyors equipped with porous pads have been developed to bring the liquid crystal display(LCD) into a non-contact state during transportation process. In this work, a theoretical model including flow property of porous media and Reynolds equation is established within a representative region in order to optimize the design parameters of a partial porous air conveyor. With the theoretical model, an optimization method using nondominated sorting genetic algorithm – II(NSGA-II) is applied for a two-objective optimization to achieve a minimum air consumption and maximum load capacity. Three Pareto-optimal solutions are selected to analyze the influence of each parameter on the characteristics of the air conveyor, and the results indicate that the position of the porous pads has the most significant impact on the performance and of course must be determined with care. Furthermore, experimental results in terms of the supporting force versus gap clearance show that the optimized air conveyor can greatly improve the load capacity over the normal one, indicating that the optimization method is applicable for practical use. 展开更多
关键词 OPTIMIZATION genetic algorithm porous media air conveyor pressure distribution
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Optimal Driving of Large Belt Conveyor with Multi-roller Variable-Frequency Drive 被引量:1
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作者 付俊青 王聪 李玉瑾 《Journal of China University of Mining and Technology》 2004年第2期231-237,共7页
in this paper, an electromechanically coupled mathematic model of multi-roller driving system for belt conveyor is set up, and the computing equations for dynamic displacement and dynamic tension of the conveyor are a... in this paper, an electromechanically coupled mathematic model of multi-roller driving system for belt conveyor is set up, and the computing equations for dynamic displacement and dynamic tension of the conveyor are also formulated when the hoister is used for straining. Based on the belt conveyor of main inclined shaft in Chengzhuang coal mine, the driving torque, driving power and starting-speed characteristic of each electric motor are studied and measured when multi-roller variable-frequency drive (power distribution 2∶1) is used. The optimal control and the optimal starting-acceleration of the multi-roller variable-frequency drive are determined by a large number of industrial experiments and theoretical calculations. 展开更多
关键词 BELT conveyor multi-roller variable-frequency DRIVE ELECTROMECHANICAL coupled mathematic model control CHARACTERISTIC starting-acceleration CHARACTERISTIC
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Applying BP neural network to detect conveyor belt fire with multi-sensors 被引量:1
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作者 郭键 李明 郭凯 《Journal of Coal Science & Engineering(China)》 2004年第2期66-69,共4页
A kind of feed forward neural network with three layers was applied to detect conveyor belt fire faster. And backward propagation (BP) algorithm was used to train the network parameters. The appropriate parameters and... A kind of feed forward neural network with three layers was applied to detect conveyor belt fire faster. And backward propagation (BP) algorithm was used to train the network parameters. The appropriate parameters and architecture of network were ob- tained after training with 81 pair of data. Matlab was used to simulate and the experi- ment result shows training time is least and error reduces most rapidly when ten neu- rons were in hidden layer and momentum coefficient is equal to 0.95. Temperature, rate of temperature change, dense of carbon monoxide and rate of carbon monoxide dense change were considered as four parameters to detect the PVC belt fire in this paper. It is indicated that the network can give alarm as fire takes place about 350 s. The network can effectively detect the fire at the early stage of conveyor belt fire. At the same time, the reliability of alarm can be increased and the anti-interference capability can be en- hanced when using this network. 展开更多
关键词 neural network FIRE conveyor belt carbon monoxide
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Experimental Study of Kinetic Properties of Pyrolysis for Conveyor Belt in Coal Mine 被引量:1
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作者 SONG Zheng-chang 《Journal of China University of Mining and Technology》 EI 2005年第4期314-316,共3页
The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis ... The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis and derivative thermo-gravimetric analysis, and the curves of pyrolysis properties were achieved. On this basis, the activation energy and reaction order of pyrolysis were obtained in combination with theoretical analysis, aiming to provide data for further numerical simulation and simulating experiment of mine fire. 展开更多
关键词 conveyor belt COMBUSTION PYROLYSIS mine fire
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Dynamics simulation of the belt conveyor possessing feedback loop during starting 被引量:1
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作者 席平原 张海涛 刘军 《Journal of Coal Science & Engineering(China)》 2005年第1期83-85,共3页
Synthesizing the mechanical models of the belt, the driver and the take-up device, the dynamics model was established on the longitudinal vibration of the overall belt conveyor system with finite elemental method, and... Synthesizing the mechanical models of the belt, the driver and the take-up device, the dynamics model was established on the longitudinal vibration of the overall belt conveyor system with finite elemental method, and S-function simulation block of asynchronous motor owing feedback function was built in Matlab/Simulink software, the simulation block indicates that motor rotation speed and its output moment vary with load and time, and the motor is a dynamic feedback system in working process. The state space block was adopted to express model of the belt. Thus it created simulation model of established dynamic model of overall belt conveyor system with Mat- lab/Simulink software, and simulates the course of starting by properly setting simulation parameters, and processes data for visualization. 展开更多
关键词 belt conveyor dynamics simulation starting process feedback loop
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Development of belt conveyor driving system 被引量:1
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作者 付峻青 王聪 霍伟 《Journal of Coal Science & Engineering(China)》 2004年第1期83-87,共5页
A short review for the existing various driving methods for belt conveyor was given, which include the analysis and comparison about the advantages, disadvantages and suitable application range of these methods. Based... A short review for the existing various driving methods for belt conveyor was given, which include the analysis and comparison about the advantages, disadvantages and suitable application range of these methods. Based on this the vari-able-frequency-control(VFC) method for belt conveyor drive was fully discussed with focus on its application in medium-high voltage range. The principle of Neutral Point Clamped (NPC) Three-Level Inverter using high-voltage IGBTs together with the control strategy of rotor field-oriented vector control for induction motor drive were illustrated. 展开更多
关键词 belt conveyor driving system variable-frequency-control three-level inverter
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