2011 Vol. 37, No. 1

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Research of Key Technologies about Electrical Safety of Coal Mine
SUN Ji-ping
2011, 37(1): 1-4.
<Abstract>(53) <PDF>(14)
Abstract:
The paper analyzed fire sources of domestic gas explosion accidents from 2005 to 2009 and got a conclusion that gas explosion accidents were mostly caused by electrical fire source, which accounted for 48.1%. It analyzed safety performances of mine-used electrical devices and proposed operation places and safety requirements of each type of electrical devices. Firstly, systems and devices with weak current for coal mine monitoring, communication, control and signals should primarily be intrinsically safe and signals transmitting between the devices must be intrinsically safe. Secondly, electrical devices with large power should be flameproof type devices and wiring cavity of the devices should be separated from main cavity. Thirdly, special cap-lamp cannot be operated on or off when gas concentration achieves explosion concentration value. Fourthly, explosion-proof electrical devices should be used in non-explosion places such as underground shaft station of mine with low gas concentration. Fifthly, trolley locomotive and normal mine-used electrical devices cannot be used in mine with coal and gas outburst. Sixthly, time-delay measures should be used in under-voltage and no-voltage protection of underground electrical devices so as to decrease cutting off times of local ventilator. Seventhly, immersible pumps with large power should be used for underground draining devices. Eighthly, switches should be set at air-intake places of total wind pressure, otherwise methane sensors should be set with functions of power-off and interlocking when methane is over limit. The paper provides some guidance to improve electrical safety performance of coal mine and avoid or decrease accidents of gas explosion and mine submerging.
Research of Mine-used Service System of Dispatching and Communication Based on Soft Switch Platform and Its Implementatio
GU Jun, HUO Zhen-long, XU Xi-liang, WANG Wei
2011, 37(1): 5-9.
<Abstract>(48) <PDF>(6)
Abstract:
In view of special requirements of dispatching functions of voice communication in coal mine underground, the paper analyzed soft switch technique for VoIP communication, proposed an implementing method of mine-used dispatching and communication service in soft switch platform, and introduced a design scheme of mine-used service system of dispatching and communication based on soft switch platform by use of FreeSWITCH. The system provides dispatching and communication services such as calling, monitoring, interjecting, contesting calling, forcedly demolishing calling, group calling, listening only, listening and speaking, adding/deleting provisional members, setting/canceling chairman, recording and so on with high expansibility, and can select hardwares of server according to number of users underground. The testing result verified validity of the system, which provides a practical scheme for dispatching and communication service platform in coal mine underground.
Research of Multi-layer DEM Modeling and Its Application in Stratum Visualizatio
WEI Yong-yong
2011, 37(1): 9-12.
<Abstract>(46) <PDF>(4)
Abstract:
The paper proposed a method of using visual language IDL as modeling tool to realize 3D visualization of stratum. Basic idea of the method is as following: (1) Obtaining statue data of stratum, making interpolation analysis of the data, and expressing surface of stratum by regular or irregular grid networks to form single-layer DEM. (2) Interpolating or fitting each surface of stratum according to forming method of single-layer DEM so as to obtain distribution of 3D space of different stratum. If there is no fault in stratum, connecting the grid networks of adjacent surfaces of stratum to build topological relation, which can obtain solid model of stratum. If there is intersection in stratums, doing detection of sample points or height judgment for cross region to determine range of the cross region to build 3D model of stratum. (3) Constructing volume data, using multi-layer DEM to make hierarchical assignment, and using different properties to mark stratums, which can realize visualization of geological space. The test result showed that the method has certain practicality.
Design of Vibration Detecting System for Rolling Bearing of Shearer Based on DSP
CHEN Qiao-ying, LIN Hang, XIANG Ji-feng
2011, 37(1): 13-15.
<Abstract>(33) <PDF>(7)
Abstract:
The paper briefly described mathematics model of vibration of rolling bearing of shearer and structure and basic working principle of eddy-current vibration displacement sensor, proposed a design scheme of vibration detecting system for rolling bearing of shearer, which takes TMS320F2812 as core controller and eddy-current vibration displacement sensor as front signal collecting part, and gave hardware design and software flow of the system. The underground testing result showed that the system has high reliability and strong real-time performance.
Hardware Design of Intelligent Integrated Protector for Mine Low-voltage Vacuum Feeding Switch
HUAI Li
2011, 37(1): 16-18.
<Abstract>(46) <PDF>(5)
Abstract:
The paper introduced hardware design of an intelligent integrated protector for mine low-voltage vacuum feeding switch based on digital signal processor and expounded technical innovations in process of hardware design of the intelligent integrated protector, including using dsPIC30F6014A digital signal processor, designing negative voltage producing circuit and standby power supply and adding LCD back-lighted control circuit and input part of gas frequency. The intelligent integrated protector adopts four-layer circuit-board structure to decrease size and improve anti-interference ability, and rowed wiring structure of out wiring terminal for convenient change underground. The testing result showed the feasibility of the intelligent integrated protector.
Design of a Battery-powered Early Warning Circuit for Shearer Starting
AN Mei-zhen, QIAN Jiang-yong, CHEN Hu, QIU Jin-bo
2011, 37(1): 19-22.
<Abstract>(44) <PDF>(5)
Abstract:
The paper introduced design schemes of software and hardware, debug methods, problems in debug process and optimization methods of a battery-powered early warning circuit for shearer starting. The circuit takes 12 V battery as system power supply, uses MSP430F149 single-chip microcomputer to control process of early warning when shearer body is powered up, and real-timely monitors battery capacity. If battery voltage checked by the single-chip microcomputer is lower than low-voltage threshold value preset in program, the circuit would give out blinking signal, which can remind users to charge the system battery. The whole circuit works in low power dissipation mode when it is idle to prolong service time. After debug and optimization, the circuit's program runs correctly and static power dissipation of the circuit is only 0.2 mA, which meets design requirement of low power dissipation.
Research of Method of On-line Fault Line Selection and Location of Underground Cable
SUN Quan-cai, JIN Li
2011, 37(1): 23-27.
<Abstract>(30) <PDF>(6)
Abstract:
In order to solve problems that it is hard to confirm fault position when single-phase grounding fault happens in underground power supply system and existing off-line distance measured methods are poor in precision, the paper analyzed characteristics of single-phase grounding fault of underground power supply system with cable and proposed a method of on-line fault line selection and location of underground cable. The method uses polarity of transient zero-sequence reactive power in frequency band of line selection to select fault line when single-phase grounding fault happens in power supply system, and takes zero-sequence voltage of system's bus and zero-sequence current of lines at faulting time as input samples to train wavelet neural network based on characteristics that transient signals with high frequency of some frequency bands map fault distance, so as to realize fault location. The Simulink simulation result verified validity and accuracy of the methods.
Research of Influence of OLTC on Static Voltage Stability Limit
DUAN Jun-dong, ZHU Shan-sha
2011, 37(1): 28-31.
<Abstract>(51) <PDF>(4)
Abstract:
For problems that voltage stability phenomenons caused by OLTC action and load dynamic characteristics are complicated and grasped hardly, the paper analyzed and researched influence of transformation ratio adjustment of OLTC on static voltage stability limit through Pmax-φ and Vcr-φ curves and critical transformation ratio corresponding to OLTC adjustment, so as to get conclusions as following: the Pmax-φ and Vcr-φ curves gradually shift upward with continuous increment of transformation ration of OLTC; the Pmax-φ and Vcr-φ curves gradually shift down with continuous decrease of transformation ration of OLTC; during adjustment of transformation ratio of OLTC, the adjustment range cannot exceed adjustment area determined by critical transformation ratio. The result of an example simulation proved that Pmax-φ and Vcr-φ curves can well describe influence of OLTC adjustment on static voltage stability limit.
Design of Monitoring Node of Coal Mine Gas, Temperature and Humidity Based on ZigBee Protocol
LEI Lin, DONG Hua-li
2011, 37(1): 32-34.
<Abstract>(56) <PDF>(4)
Abstract:
The paper introduced a design scheme of monitoring node of coal mine gas, temperature and humidity based on ZigBee protocol and CC2430 chip. The node firstly uses model LXK-3 gas sensor and model SHT11 temperature and humidity sensor to collect information of gas concentration, temperature and humidity, then processes relational data through 8051 microcontroller embedded in CC2430, and finally realizes ZigBee wireless communication between the nodes by use of functions of data receiving and sending of CC2430. The testing result showed that the node can transmit data correctly.
Research of Complete Core-drilling Technology of Coal Seam and Influence Factors on It
ZHANG Jian-jun, JIANG Cheng-lin, WU Ai-ju
2011, 37(1): 35-37.
<Abstract>(39) <PDF>(5)
Abstract:
In order to solve the problem that coal seam can be drilled only upward but not downward in process of uncovering coal of crossheading and shaft, a core-drilling device of dual-core and single-switch was used to do core-drilling test in shafts of some mine in Shanxi province and crossheading tunnel of Licun Coal Mine of Lu'an Group. Main influencing factor of failing in down core-drilling was summarized, which was residual water in borehole. Some measures were adopted to drain the residual water, including grouting, pumping water and deslagging with pressure air in whole core-drilling process, so as to realize complete core-drilling of coal seam. It was pointed out that the sign of successful core-drilling is that a lot of dry coal dust bursts forth form drilling hole in drilling process of core-drilling device in coal seam.
Research of a Novel Active Power Smoothing Control Strategy for Double-fed Wind Turbine Generator
WANG Xiao-lan, ZHANG Shu-xi
2011, 37(1): 38-43.
<Abstract>(48) <PDF>(3)
Abstract:
In order to solve fluctuation problem of outputting active power of wind turbine generator in certain range caused by uncertainty of wind energy, a large inertia of wind turbine generator and response delay of wind turbine generating system, the paper proposed a novel active power smoothing control strategy for double-fed wind turbine generator. The control strategy adopts coordinated control strategy of variable propeller and variable speed in total wind speed range and on the basis adds a control link of active power error, which takes auxiliary controll dictates of rotor voltage as feedback variable to join into primary controlling dictates of rotor voltage to control SPWM pulse generator, so as to realize smoothing control of outputting active power of stator of wind turbine generator. Matlab/Simulink simulation results indicated that the control strategy effectively suppress fluctuations of outputting active power of double-fed wind turbine generator compared with traditional control strategies.
Research of Audio Codec System Based on SPI Protocol and Its Desig
XU Bo, GUO Qiu-mi
2011, 37(1): 44-49.
<Abstract>(46) <PDF>(5)
Abstract:
The paper introduced SPI communication protocol, proposed a design scheme of audio-stream decoding system by use of ARM-controller LPC2368 and voice-processing chip VS1003, and described structure, transmission theories of SCI and SDI of the system and design of key codes of the system's software in details. The system can realize playing function of audio-analog signals perfectly by initialization debugging and sine-wave testing.
Research of Stability of East Slope of Bayan Obo Iron Mine
ZHANG Fei, LI Mo-ran, ZHOU Lian-chun, SUN Bao-lei, CAO Hua
2011, 37(1): 50-52.
<Abstract>(48) <PDF>(4)
Abstract:
For three unstable landslides of C area of Bayan Obo Iron Mine, with data of engineering geological exploration and rock mechanics test, the paper analyzed and calculated several measures for the secondary reinforcement including cutting slope, reinforcement by anchor cable and grouting by use of 5.5 edition of Lizheng soil analysis software and Canadian rock slope stability analysis software SLIDE5.0, and determined whether the secondary reinforcement measures are effective through the calculated safety factor. The analysis and calculation result showed that the secondary reinforcement measures can make safety factor of the most dangerous landslide to achieve 1.186, which meets requirement of designing safety factor of landslide's stability. At last, it proposed several notices about implementation of the secondary reinforcement measures.
Measurement, Calculation and Analysis of Ground Electric Field of Super High-voltage Transmission Line
FU Chao-guo, SUN Yan-zhou
2011, 37(1): 52-54.
<Abstract>(55) <PDF>(4)
Abstract:
By PMM8053B electromagnetic radiation analyzer and EHP-50C electromagnetic field probe with power frequency, electric field intensity of 500 kV super high-voltage transmission line was measured in some area and electric field intensity in open zone of the area was calculated by use of equivalent charge method. Through comparing the measured and calculated results by use of Matlab, conclusions were gotten that the calculated results are mainly consistent with the measured ones and electric field intensity in buildings and woods is far less than the one in open zone.
Discussion of Problems Needed Attach Importance to in Automation Construction of Coal Mine Enterprise
ZHAO Zeng-yu
2011, 37(1): 55-57.
<Abstract>(29) <PDF>(3)
Abstract:
The paper discussed problems need attaching importance in automation construction of coal mine enterprise and proposed some suggestions for promoting the construction, including drawing up corresponding policies more quickly, paying attention to modularized and intellectualized design of automation systems and construction of stand-alone automation and single-system automation, and attaching importance to selection and application of sensor, implementing machine, visualization technology and optical fiber technology, convenient and safety performances of design of automation system and development of alterable and expansive automation system.
Research of Preventing Longitudinal Tearing of Belt Conveyor of Coal Mine
CAO Jian, ZHANG Shu-yang, ZHANG Shu-li, GENG Bo
2011, 37(1): 57-59.
<Abstract>(28) <PDF>(11)
Abstract:
The paper analyzed main causes of longitudinal tearing accident of belt conveyor of coal mine, namely belt could be teared by anchor pole, puncheon, waste rock or roller, and proposed some preventing methods for longitudinal tearing of belt conveyor including strengthening routing inspection, using belt with pre-tearing net as far as possible, and setting protecting sensors of pre longitudinal tearing. The paper can provide certain guidance to prevent longitudinal tearing accident of belt conveyor of coal mine.
Analysis of Necessity and Feasibility of CAN Bus Used in Safety Protection System of Mine-used Diesel Vehicle
ZHOU Xu, YAN Wei-guang, SUN Yong, ZHANG Li-bin, CHEN Ya
2011, 37(1): 59-61.
<Abstract>(32) <PDF>(3)
Abstract:
The paper introduced application status of safety protection system of mine-used diesel vehicle at present and analyzed necessity and feasibility of CAN bus technology used in the safety protection system and its applying advantages. It pointed out that application of CAN bus technology in safety protection system and other control systems of mine-used diesel vehicle is good for realizing optimization and modernization of electrical control scheme of whole diesel vehicle.
Reliability Design of Electrical Control System of Coal Mine Tunneller
WANG De-guang
2011, 37(1): 61-63.
<Abstract>(52) <PDF>(4)
Abstract:
The paper briefly introduced composition of electrical control system of coal mine tunneller, analyzed some design factors which affect reliability of electrical control system of tunneller such as technique security, software reliability, electromagnetic compatibility and environment adaptability, and proposed concrete reliability design schemes of electrical control system, which can provide some technique support for more reliable and safer application of electrical control system of coal mine tunneller.
Research of Real-time Performance of Profibus-DP Single Master-station System
CHEN Mei, YAO Qi-yun, LI Xin, CHEN Wei, LIU Zhen-ying
2011, 37(1): 64-67.
<Abstract>(55) <PDF>(4)
Abstract:
The paper analyzed operating mechanism of data link layer of Profibus-DP protocol, described time parameters that compose Profibus-DP bus cycle in details, and gave concrete calculating formulas of real-time indexes of Profibus-DP system named message cycle time, token target rotation time and system reaction time. Combining an example of some Profibus-DP single master-station system, it analyzed factors which affect real-time performance of Profibus-DP single master-station system through calculating system reaction time, and finally proposed methods to improve real-time performance of Profibus-DP single master-station system, including improving communication speed and decreasing number of substations and changed data.
Application Status of Data Mining Technology in Power Marketing System
HAO Xiao-hong, ZHU Jie, WANG Wei-zhou, HU Zhen-bang
2011, 37(1): 68-71.
<Abstract>(59) <PDF>(4)
Abstract:
For problems of incomplete data collection and certain inaccurate data, the paper analyzed and discussed application status and prospect of data mining technologies such as association rule, classification, time series and series mining, clustering, space mining in power marketing system based on data characteristics of power marketing system.
Discussion of Design of Coal Mine Safety Management System Based on Fingerprint Identificatio
XU Qin
2011, 37(1): 72-74.
<Abstract>(36) <PDF>(3)
Abstract:
By analyzing existing status of coal mine safety management, the paper proposed a coal mine safety management system based on fingerprint identification technology and gave the general design idea, design method and design schemes of software and hardware. The system adopts fingerprint identification technology to make authentication for downhole workers and restrain workers training, so as to standardize workers' action and improve supervision for managers.
Technology of Spraying for Dust Suppression in Fully Mechianized Face and Its Applicatio
KOU Li-wen, JIANG Shu-guang, WANG Lan-yun, ZOU Li-li, LI Ya-dong
2011, 37(1): 75-78.
<Abstract>(50) <PDF>(4)
Abstract:
The paper analyzed dust source and dust generating characteristics in fully mechanized face and emphatically introduced methods of spraying for dust suppression applied in processes of shearer mining, support moving, coal caving, crusher working, coal transshipping and dust-catched water curtain. The practical application in Changcun Coal Mine verified effectiveness of the technology of spraying for dust suppression.
Monitoring and Control System of Digital Mine Hoist Based on Double Ring Networks
SONG Qing-jun, JIANG Hai-yan, YANG Yong-teng, GUO Fan-ca
2011, 37(1): 78-80.
<Abstract>(74) <PDF>(8)
Abstract:
The paper introduced application status of industrial Ethernet in digital mine construction, proposed network framework of a digital monitoring and control system of mine hoist based on double ring networks and Siemens S7-200 PLC, and introduced software and hardware designs of the system. The system can realize monitoring functions of working status, running parameters, fault parameters and fault status of mine hoist and control functions of starting, accelerating, stably running, decelerating, stopping and emergency braking of mine hoist. The actual application showed that the system runs stably and reliably and has perfect detection and protection functions.
Design of 1-wire Bus Mode Monitoring System of Ground Freezing and Its Application
ZHAO Yu-ming, ZHAI Yan-zhong, LI Chang-zhong
2011, 37(1): 80-83.
<Abstract>(28) <PDF>(7)
Abstract:
In order to solve problems of multi-wire and multi-point measuring mode used in ground freezing construction in China at present such as large cable dosage, complex wiring and installation, high cost and large transmitting waste of signal, the paper proposed a design scheme of monitoring system of ground freezing by use of 1-wire technology and introduced software and hardware designs of the system. Application of the system in freezing construction of submine of Zhangji Coal Mine verified stability and reliability of the system, but forecasting function of the system needs to be perfected and improved further.
Application of Electric Power Monitoring System of Coal Mine Based on Industrial Ethernet
LI Da-feng, ZHAO Shuai, WU Feng
2011, 37(1): 84-86.
<Abstract>(40) <PDF>(6)
Abstract:
The paper introduced structure and application of electric power monitoring system of coal mine based on industrial Ethernet in Qianqiu Coal Mine. The practise showed the system can realize function of remote monitoring of power supply systems of underground and ground substations, which can decrease production cost and improve working efficiency.
Design of Intelligent Protection System of Belt Conveyor Based on PLC
MA Yong-hui, SUN Yan-bing, WANG Gui-hua
2011, 37(1): 86-89.
<Abstract>(51) <PDF>(5)
Abstract:
In view of problems of single function, low reliability and poor integration and expansibility of system in existing protection system of belt conveyor of coal mine, and comparing common fault types of belt conveyor, the paper proposed an intelligent protection system of belt conveyor based on PLC and introduced hardware structure and software design of the system. The system can be operated singly and locked with several levels, has perfect interfaces of communication networking with strong expansibility, supports transmission through industrial Ethernet and has intelligent integrated control function. The actual application verified validity and reliability of the system.
Principle of On-line Monitoring System of Mine Main Ventilator and Its Applicatio
MIAO Yu-song, SONG Hai-jun
2011, 37(1): 89-92.
<Abstract>(34) <PDF>(7)
Abstract:
The paper analyzed design principle of software and hardware of on-line monitoring system of mine main ventilator and introduced concrete application of the system in Junde Coal Mine from points of sensor selection, communication mode, monitoring interface of industrial control computer. The practice showed that the system runs stably, decreases labor intensity, effectively avoids accidents of sudden pause of main ventilator and improves safety and reliability performance of main ventilator running.
Design of Control System of Electric Executer of Hydro-valve Based on STC89C51
CAO Jing-long, AN Bai-xiu, NIU Jie
2011, 37(1): 92-95.
<Abstract>(65) <PDF>(5)
Abstract:
The paper introduced structure and working principle of an electric executer of hydro-valve based on STC89C51 single-chip microcomputer and expounded composition and design schemes of software and hardware of control system of the electric executer. The control system takes STC89C51 single-chip microcomputer as core, uses ring distributor and power amplifier to control rotator speed and rotator angle of step motor so as to control opening degree of the hydro-valve, and adopts a flow sensor and a pressure sensor to collect hydro-parameter signals, which are sent to STC89C51 single chip microcomputer after AD conversion so as to form closed loop control. The control system has functions of CAN communication and human-machine interaction.
Design of Automatic Control System of Active Carbon Project
ZHOU Guo-bi
2011, 37(1): 96-98.
<Abstract>(36) <PDF>(2)
Abstract:
In order to solve problems of many manual labors required, unstable production quality and low production rate because correlative parameters cannot be real-timely monitored in producing process of active carbon production of existing production lines of active carbon, the paper introduced composition, network structure and design of man-machine interface of an automatic control system of active carbon project. The system integrates producing automatic subsystems of active carbon project through industrial Ethernet and field bus technologies and realizes functions of sequential control, close-down linkage, parameter collection, real-time monitoring of key parameters and automatic adjustment of key links of whole active carbon project. The actual application verified the system's feasibility and validity.
Application of TE151A Hydraulic Pressure Station in Mine Hoist and Its Maintenance
TAO Zhi-yong
2011, 37(1): 98-100.
<Abstract>(31) <PDF>(7)
Abstract:
The paper introduced composition and working principle of TE151A hydraulic pressure station of mine hoist and expounded daily maintaining methods of TE151A hydraulic pressure station. For common fault phenomenas of TE151A hydraulic pressure station, it analyzed possible fault causes and proposed corresponding solving measures. The paper provides some reference for operating and maintaining workers of TE151A hydraulic pressure station.
Research of Harm Analysis of Capacitance Current of Renlou Coal Mine and Its Treatment
DUAN Lian, DU Gao-xi
2011, 37(1): 100-102.
<Abstract>(63) <PDF>(4)
Abstract:
In order to solve the problem that single-phase grounding capacitance current of isolated neutral system could cause secondary disaster and equipment damage in distribution network and generate single-phase arc grounding over-voltage and ferromagnetic resonance over-voltage, the paper analyzed and evaluated testing data of capacitance current of distribution network of Renlou Coal Mine, established a treating scheme of capacitance current according to evaluating results, namely changing isolated neutral system to neutral grounding running mode by arc suppression coil, and gave concrete implementing scheme. The running result showed that the scheme greatly decreases rate of accidents of arc grounding over-voltage with high amplitude and restrains ferromagnetic resonance over-voltage, which was good for prolonging usage time of cable.
Research of Harm Analysis of Capacitance Current of Renlou Coal Mine and Its Treatment
DUAN Lian
2011, 37(1): 102-104.
<Abstract>(52) <PDF>(4)
Abstract:
In order to solve the problem that single-phase grounding capacitance current of isolated neutral system could cause secondary disaster and equipment damage in distribution network and generate single-phase arc grounding over-voltage and ferromagnetic resonance over-voltage, the paper analyzed and evaluated testing data of capacitance current of distribution network of Renlou Coal Mine, established a treating scheme of capacitance current according to evaluating results, namely changing isolated neutral system to neutral grounding running mode by arc suppression coil, and gave concrete implementing scheme. The running result showed that the scheme greatly decreases rate of accidents of arc grounding over-voltage with high amplitude and restrains ferromagnetic resonance over-voltage, which was good for prolonging usage time of cable.
Part IV of Lecture of Internet of Things and Sensor Mine —Plan and Construction of Internet of Things of Sensor Mine and Coal Enterprise
ZHANG Shen, DING En-jie, XU Zhao, HUA Gang
2011, 37(1): 105-105.
<Abstract>(62) <PDF>(6)
Abstract:
The paper pointed out that M2M platform of Internet of things of sensor mine should provide open interfaces for services of application layer and suit to requirements of perfecting "six systems" for safe act of rescue, leaders going into mine and disaster monitoring of coal mine. It gave four-layer structure of Internet of things of coal enterprise, pointed out that construction of Internet of things of sensor mine is a key of construction of Internet of things of whole coal enterprise and main functions of the other layers should be safety and resource management of coal mine, and analyzed application modes of Internet of things of coal enterprise of mining group, province and the state. At last, it proposed problems which need paying attention to in construction of Internet of things of sensor mine.

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