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1、精選優(yōu)質(zhì)文檔-傾情為你奉上關于煤礦安全監(jiān)控系統(tǒng)技術的研究無線射頻的新的發(fā)展和運用使得RFID(射頻識別)技術的應用越來越廣泛。同時結合礦山與RFID技術的特點,我們建立了一個地下的安全完整的、實時靈活的監(jiān)測系統(tǒng)。這套系統(tǒng)能在發(fā)生危險時自動報警并且提高搜索和救援的效率。該系統(tǒng)可以管理危害氣體的濃度、規(guī)劃工人的安排、進出巷道通過工作的訪問控制、巷道人員的分布和工人的資料,實現(xiàn)地下管理的信息化和可視化,提高礦業(yè)生產(chǎn)管理水平和礦井安全生產(chǎn)水平。關鍵詞:射頻識別,安全監(jiān)控系統(tǒng),電子標簽,讀寫器煤礦事故往往發(fā)生在中國近幾年,除了礦業(yè)主的安全和法律意識薄弱,滯后的安全機構和采礦的人員和設備的不完善管理人員是
2、重要原因。通過分析近期內(nèi)一些十分嚴重的事故,一般存在以下常見問題:(1)地面人員和地下人員之間的信息溝通不及時;(2)地面人員不能動態(tài)地掌握井下人員的分布和操作情況,并且不能掌握地下人員的確切位置;(3)一旦煤礦事故發(fā)生,救援效率低,效果較差。因此,準確、迅速實施煤礦安全監(jiān)控職能非常重要和緊迫,有效管理礦工,并確保救援高效率的運作。 文章中提出的煤炭采礦人員和車輛安全監(jiān)測系統(tǒng)可以跟蹤、監(jiān)視和定位在礦井實時的有害氣體,人員和車輛以及提供有關網(wǎng)絡的礦井巷道,個人的定位,車輛的位置,危險區(qū)域的動態(tài)信息和地面人員相應線索。如果發(fā)生意外,該系統(tǒng)還可以查詢有關人員的分配,人員數(shù)量,人員撤離路線,以提供從事
3、故救援監(jiān)視計算機科學依據(jù)。同時,管理人員可以利用系統(tǒng)的日??记诠δ軐嵤┑V工考勤管理。 一、RFID技術簡介 射頻識別是一種非接觸式自動識別技術進行排序,可以自動識別的無線電頻率信號的目標,迅速跟蹤貨物和交換數(shù)據(jù)。身份查驗工作無須人工操作,并能在各種嚴峻的環(huán)境下工作。RFID技術可識別高速對象和多個標簽同時識別,操作簡單快捷。RFID技術是產(chǎn)生于第二次世界大戰(zhàn),它是在繼承傳統(tǒng)的編碼技術,其主要的核心部分是電子標簽,識別系統(tǒng)可以讀取電子標簽存儲通過無線電波的資料排放的讀者從幾厘米到數(shù)米的作家,并確定貨物的身份,人民和電子標簽代表的對象。1.1 RFID的系統(tǒng)組成 射頻識別系統(tǒng)(見圖1)通常由電子標
4、簽,讀寫器和計算機通訊網(wǎng)絡組成。1.1.1電子標簽 電子標簽存儲相關信息確定的對象,它通常是在確定的目標付諸表決,并通過它儲存的信息可以讀取和射頻讀寫器寫入通過非接觸模式。1.1.2讀寫器 讀寫器是一個可以用來讀取和寫入射頻技術的電子標簽信息的設備。標簽上的信息的讀寫器讀取都可以處理,由計算機網(wǎng)絡系統(tǒng)傳輸。1.1.3計算機通信網(wǎng)絡 在RFID系統(tǒng),計算機通信網(wǎng)絡一般是用來管理數(shù)據(jù)和完整的通信傳輸功能。該讀寫器可以通過連接標準接口的計算機通信網(wǎng)絡,實現(xiàn)通訊和數(shù)據(jù)傳輸。1.2 RFID的工作原理系統(tǒng) RFID技術是一種非接觸式信息傳遞的通過空間耦合交變磁場或電磁場(射頻信號實現(xiàn)方式排序),并通過傳
5、輸?shù)男畔⒋_定的目標。它的工作原理可描述如下:在一個區(qū)域讀寫器發(fā)出的能量,形成電磁場,以及區(qū)域的大小取決于工作頻率和天線尺寸,當電子標簽通過此區(qū)域,系統(tǒng)檢查了讀寫器和存儲電磁波由讀寫器發(fā)出的信號能量是由標記電能需要,和標記的內(nèi)部信息傳遞給讀者,作家的對無線電波的形式,讀者,作家接受了電子標簽的數(shù)據(jù),編碼并實施故障檢查判斷數(shù)據(jù)的有效性,并傳送數(shù)據(jù),為數(shù)據(jù)處理計算機通信網(wǎng)絡。標簽進入磁場后,接收解讀器發(fā)出的射頻信號,憑借感應電流所獲得的能量發(fā)送出存儲在芯片中的產(chǎn)品信息(Passive Tag,無源標簽或被動標簽),或者主動發(fā)送某一頻率的信號(Active Tag,有源標簽或主動標簽);解讀器讀取信息
6、并解碼后,送至中央信息系統(tǒng)進行有關數(shù)據(jù)處理。一套完整的RFID系統(tǒng), 是由閱讀器(Reader)與電子標簽(TAG)也就是所謂的應答器(Transponder)及應用軟件系統(tǒng)三個部份所組成, 其工作原理是Reader發(fā)射一特定頻率的無線電波能量給Transponder, 用以驅(qū)動 Transponder電路將內(nèi)部的數(shù)據(jù)送出,此時 Reader便依序接收解讀數(shù)據(jù), 送給應用程序做相應的處理。以RFID卡片閱讀器及電子標簽之間的通訊及能量感應方式來看大致上可以分成, 感應偶合(Inductive Coupling) 及后向散射偶合(Backscatter Coupling)兩種, 一般低頻的RFI
7、D大都采用第一種式, 而較高頻大多采用第二種方式。閱讀器根據(jù)使用的結構和技術不同可以是讀或讀/寫裝置,是RFID系統(tǒng)信息控制和處理中心。閱讀器通常由耦合模塊、收發(fā)模塊、控制模塊和接口單元組成。閱讀器和應答器之間一般采用半雙工通信方式進行信息交換,同時閱讀器通過耦合給無源應答器提供能量和時序。 在實際應用中,可進一步通過Ethernet或WLAN等實現(xiàn)對物體識別信息的采集、處理及遠程傳送等管理功能。應答器是RFID系統(tǒng)的信息載體,目前應答器大多是由耦合原件(線圈、微帶天線等)和微芯片組成無源單元。1.3 RFID的技術特點1.3.1數(shù)據(jù)讀取和寫入 RFID讀取器可以讀取數(shù)據(jù)到數(shù)據(jù)庫中沒有接觸,一
8、旦和處理多個標簽,并寫入了下一階段物流處理標簽的物流處理的狀態(tài)。1.3.2小型化和多樣化的形式 RFID將不會受到大小或形式時,它讀取數(shù)據(jù)有限,因此無須使用固定大小的文件或打印質(zhì)量以適應精度。此外,電子標簽的RFID可以應用在不同產(chǎn)品體積小,所以我們可以更靈活地控制生產(chǎn)線產(chǎn)品的生產(chǎn),特別是應用程序。1.3.3反污染 RFID技術具有強大的抗水,污染性質(zhì),石油或毒品。而在黑暗或污染環(huán)境,RFID還可以讀取數(shù)據(jù)。1.3.4重復使用 由于RFID是電子數(shù)據(jù),可重復寫入,所以標簽可以重復使用。1.3.5滲透性 如果RFID是由紙張,木材,塑料或非金屬或非透明材料覆蓋,它可以進行交流,除了為這些鐵桿或其
9、他金屬材料。1.3.6數(shù)據(jù)存儲容量大 數(shù)據(jù)容量將擴大與記憶力的開發(fā),以及由所運貨物的材料質(zhì)量越大,該卷的容量的要求,標簽也增加,RDID不會受到限制。1.3.7系統(tǒng)安全 該系統(tǒng)由中央計算機存儲的數(shù)據(jù),工件將在很大程度上提高系統(tǒng)的安全。1.3.8數(shù)據(jù)安全 結帳方式或循環(huán)冗余校驗方法將被用于確保數(shù)據(jù)的準確性在無線電頻率標簽儲存。二、總的設計和工作原理監(jiān)測系統(tǒng)2.1系統(tǒng)設計 除履行的功能需求,設計項目應充分考慮穩(wěn)定性,可靠性,抗干擾能力,容錯能力和異常保護,因此該系統(tǒng)的總設計應體現(xiàn)在以下幾個方面。(1)設計可以有效地識別和監(jiān)測地下人員,實現(xiàn)人性化,信息化和自動化。(2)設計可以有效地提供人員的傳遞和
10、輸出,出勤和監(jiān)測及相關管理信息,一旦事故發(fā)生,設計可確保救援的正常實施。(3)該系統(tǒng)的設計可具有本質(zhì)安全,維護和擴展。(4)設計可以有效地測試了有害氣體的濃度,并迅速作出反應。2.2系統(tǒng)工作原理 地鐵站設備發(fā)射的加密信息到外部的天線,形成一定的信號發(fā)射區(qū)。這種RFID卡由工人將被激活時,將進入發(fā)射區(qū),并與目標識別加密攜帶的信息是由發(fā)射模塊發(fā)射和變電站設備將接收這些信號,抽象的目標識別代碼,發(fā)送代碼到地面計算機系統(tǒng)完成系統(tǒng)的功能。當有害氣體的濃度達到一定值時,對變電站設備的氣體傳感器的信息傳輸?shù)紸 / D轉換器,轉換后的信息,他們傳送到監(jiān)測網(wǎng)絡,實現(xiàn)了測試和監(jiān)測。三、該系統(tǒng)的組成和結構 安全監(jiān)測
11、系統(tǒng)包括地面部分和地下部分(見圖2)。 該系統(tǒng)采用了SAP的產(chǎn)品掛設計,以確保為13小時后正常,在不斷的惡劣環(huán)境并提供電源系統(tǒng)運行斷電。 地下部分和地上部分采用了RS - 485串行接口標準的通信與RS - 232標準的串行交互連接與傳輸網(wǎng)絡。數(shù)據(jù)轉換接口,主要是由組成的電源板,信號轉換板和安全螺栓,它是在礦井口的人選,而主要是用來確保監(jiān)測點之間的地下和地面監(jiān)測信息交流中心,因此系統(tǒng)并不需要RFID技術和A / D轉換器。圖3是與地面和地下的通信信號交流。3.1地下部分 地下部分是監(jiān)測系統(tǒng)的核心部分,它包括現(xiàn)場總線和一組用于監(jiān)測和控制人員變電站系列?,F(xiàn)場總線是變電站網(wǎng)絡的連接和傳遞信息。一些變
12、電站是用于定位的地下工作者和設備的實時性。人事定位模式和設備是信號強度監(jiān)測方法,當電子標簽由一個工人站附近進行一定的定位是,通過該站獲得的信號是強烈的,所以我們可以判斷標簽的位置,而當電子標簽中的兩站疊加區(qū)域,兩站的信號強度會有所不同,我們可以通過比較判斷信號的強度,標記的位置。其他變電站主要組成由傳感器,A / D轉換器,微控制器和RFID模塊,它們可以監(jiān)視有害氣體的實時性和獲取信息的傳輸,當有害氣體濃度超過安全值,在當?shù)氐墓ぷ髌脚_和地下固定監(jiān)測點同時發(fā)出警報。在地下部分變電站采用有線通信,串行接口與RS - 232串行數(shù)據(jù)接口標準,傳輸總線和串行接口是為將來擴展系統(tǒng)的功能使用。3.2地面部
13、分 地面部分主要包括管理運作體系,它是整個安全監(jiān)測系統(tǒng)的基礎,其主要職能是完成信息獲取,實時處理和檢查點存儲。從地下不僅包括對有害氣體的濃度,但對地下的人員和設備的信息,而這些大尺寸的數(shù)據(jù)都存儲在數(shù)據(jù)庫中通過諸如監(jiān)測和控制基地的壓縮信息。四、結論 在這篇文章中,我們應用在煤炭開采管理的RFID技術,并設立了一個地下的安全與完整性監(jiān)測系統(tǒng),實時性和靈活性,這可能發(fā)生危險時自動報警,提高了搜索和救援效率。該系統(tǒng)可以管理的危害氣體濃度,規(guī)劃安排的工人,為進出巷道工程通過訪問控制,巷道支護人員和工人的數(shù)據(jù)分布,實現(xiàn)信息化和可視化管理的地下,并在很大程度上提高采礦生產(chǎn)管理水平和礦井安全生產(chǎn)水平。安全監(jiān)測
14、系統(tǒng)是基于對煤礦安全生產(chǎn),以及RFID模塊是主要的設備,以及有線通信網(wǎng)絡是韌帶,以及監(jiān)測中心PC計算機為中心的計算機管理系統(tǒng)。該系統(tǒng)可以改善礦工的安全機制,降低管理成本,該技術將是采礦安全生產(chǎn)監(jiān)管的新趨勢。參考資料Guo, Yanli. (2005). Mine Application Example of South Africa Mining Industry. Automatic Identification Technology & Application. No. 5.Klaus Finkenzeller. (2003). RFID Handbook: Fundamental
15、s and Applications in Contactless Smart Cards and Identification (second Edition). John wiley & Sons, 2003.Liu, Lili & Yao, Meng. (2004). Coal Mine Security Intelligent Control System Based on RFID. Global Electronics China. No.9. P.22-25.Nadeem Raza, Viv Bradshaw, Matthew Hague, et al. (199
16、9). Application of Technology. The Institution of Electrical Engineer, 1999.Qiu, Like. (2007). The Principle of Staff Positioning System for Those Working in Underground Coalmine and Its Application in Xinglongzhuang Coalmine. Coal Mine Modernization. No.1. P.28-29.Simson Garfinekel, Beth Rosenberg.
17、 (2005). RFID, Applications, Security and Privacy. Addison-wesley, 2005.Tan, Min & Liu, Yu. (2007). RFID Technical System Engineering and Application Directory. Beijing: China Machine Press. April of 2007.Zhou, Xiaoguang & Wang, Xiaohua. (2006). Technical Principle and Application Example of
18、 RFID. Beijing: Posts & Telecom Press. Dec. of 2006.附錄 BStudy on the Technology of the Coal Mining Safety Monitoring SystemZhi Chang, Zhangeng Sun & Junbao GuSchool of Mechanical and Electronic Engineering, Tianjin Polytechnic UniversityTianjin , ChinaE-mail: changzhi2007.coolAbstractNew dev
19、elopment and application of the wireless radio frequency make the application of the RFID (Radio Frequency Identification) technology become more and more extensively, and combining the characteristics of RFID technology with the mine, we established an underground safety monitoring system with inte
20、grality, real-time and flexibility, which could automatically alarm when dangers happen and enhance the search and rescue efficiency. The system could manage the harm-gas concentration, planning arrangement of workers, access control for the works passing in and out laneway, distribution of laneway
21、personnel and workers data, realize the informationization and visualization of the underground management, and enhance the mining production management level and the work safety level of the mine.Keywords: RFID, Safety monitoring system, E-tag, Reader-writerMining accidents often happened in China
22、in recent years, and except for mine owners weak safety and legal consciousness, the lagged safety establishments and the imperfect managements of the mining personnel and equipments were the important causes. Through analyzing several extra serious accidents in the near period, following common pro
23、blems generally existed (Qiu, 2007, P.28-29), (1) the information communication between the ground personnel and the underground was not timely, (2) ground personnel could not dynamically grasp the underground personnels distribution and operation situation, and could not exactly position undergroun
24、d personnel, (3) once the mine accident happened, the efficiency of rescue was low, and the effect was worse. Therefore, it is very important and urgent to exactly and quickly carry out the coal mining safety monitoring function (Liu, 2004, P.22-25 & Guo, 2005), effectively manage the miners, an
25、d ensure the high-efficiency operation of the rescue.The coal mining personnel and vehicle safety monitoring system proposed in the article can track, monitor and position the harmful gases, personnel and vehicles in the mine real time, and offer dynamic information about the mine laneway network, p
26、ersonal position, vehicle position, dangerous region and corresponding clews for ground personnel. If the accident happens, the system also can inquire about the personnel distribution, the personnel quantity, the personnel withdrawal line to offer scientific references for the accident rescue from
27、the monitoring computer. At the same time, the mangers can utilize the daily attendance function in the system to implement attendance management for miners.1. Introduction of the RFID technologyRFID (Zhou, 2006 & Nadeem Raza, 1999) is a sort of non-contact automatic identification technology, a
28、nd it can automatically identify the objective by the radio frequency signals, quickly track the goods and exchange data. The identification work needs not human operation, and can work under various severe environments. RFID technology can identify high-speed objects and identify multiple tags simu
29、ltaneously, and the operation is quick and simple. RFID technology was generated in the Second World War, and it is the successor of the traditional code technology, and its major core part is the E-tag, and the identification system could read the information stored in the E-tag through the radio w
30、aves emitted by the reader-writer from a few centimeters to a few meters, and identify the identity of the goods, people and objects represented by the E-tag.1.1 Composing of RFID systemRFID system (seen in Figure 1) is generally composed by E-tag, reader-writer and computer communication network(Si
31、mson Garfinekel, 2005).1.1.1 E-tagE-tag stores correlative information of the identified objects, and it is usually put on the identified objects, and the information stored by it can be read and written by the radio frequency reader-writer through the non-contact mode.1.1.2 Reader-writerThe reader-
32、writer is the equipment which can be used to read and write the information of the E-tag by the radio frequency technology. The tag information read by the reader-writer can be managed and transmitted by the computer network system.1.1.3 Computer communication networkIn the RFID system, the computer
33、 communication network is generally used to manage the data and complete the function of communication transmission. The reader-writer can connect with the computer communication network by the standard interface to realize the communication and data transmission.1.2 Work principle of RFID systemRFI
34、D technology is a sort of non-contact information transfer mode realized by the radio frequency signals through space coupling (alternating magnetic field or electromagnetic field), and it identifies the objective through the transferred information. Its work principle can be described as follows (K
35、laus Finkenzeller, 2003): reader-writer emits energy in one region, form the electromagnetic field, and the size of the region is decided by the work frequency and antenna size, and when the E-tag passes this region, the system checks the signal of the reader-writer and stores the electromagnetic wa
36、ve energies emitted by the reader-writer to be the electric energy needed by the tag, and the tag transmits the interior information to the reader-writer by the form of the radio wave, and the reader-writer accepts the data of the E-tag, encodes and implement fault check to judge the validity of the
37、 data, and transfers the data to the computer communication network for the data processing.1.3 Technical characteristics of RFID1.3.1 Data read and writeRFID reader can read the data to the database without contact, and process multiple tags once, and write the logistic processing state into the ta
38、g for the logistic processing in the next stage.1.3.2 Miniaturized and diverse formRFID will not be limited by the size or form when it reads data, so it needs not to use the paper with fixed size or print quality to fit for the precision. In addition, E-tag of RFID can be applied in different produ
39、cts by small size, so we can more flexibly control the production of the products, especially the application on the production line.1.3.3 Anti-pollutionRFID possesses strong anti-pollution nature for water, oil or drugs. And in the dark or polluted environment, RFID also can read data.1.3.4 Repetit
40、ive useBecause RFID is electric data which can be written repetitively, so the tag can be used repetitively.1.3.5 PenetrabilityIf RFID is covered by the paper, wood, plastics or non-metal or non-transparent materials, it can communicate through these materials except for the irons or other metals.1.
41、3.6 Big memory capacity of dataThe data capacity will be extended with the development of the memory scale, and the quality of the material carried by the goods is larger, the requirement of the capacity for the volume label also increase, and RDID will not be restrained.1.3.7 System safetyThe syste
42、m stores the data from the central computer to the work piece which will largely enhance the safety of the system.1.3.8 Data safetyThe checkout method or the cycle redundancy checkout method will be used to ensure the data veracity stored in the radio frequency tag.2. Total design and work principle
43、 of the monitoring system2.1 System designExcept for fulfilling the function requirements, the design project should fully consider the stability,reliability,anti-jamming ability, fault-tolerance ability and abnormity protection, so the total design of the system should be embodied in following aspe
44、cts.(1) The design could effectively identify and monitor underground personnel, and realize the humanization,informationization and automatization.(2) The design could effectively offer personnels passing in and out, attendance and monitoring and relative management information, and once the accide
45、nt happens, the design could ensure the normal implementation of the rescue.(3) The design of the system could possess the natures of safety, maintenance and expansion.(4) The design could effectively test the concentration of harmful gases and quickly react.2.2 System work principleThe underground
46、station equipment emits the encrypted information to the exterior by the antenna and forms certain signal emission region. The RFID cards carried by the workers will be activated when they enter into the emission region, and the information carried with the encrypted objective identification are emi
47、tted by the emission module, and the substation equipment will receive these signals and abstract the objective identification code, and transmit the code to the ground computer system to complete the function of the system. When the concentration of the harmful gases achieves certain value, the gas
48、 sensor of the substation equipment transmits the information to the A/D converter, and after the information are converted, they are transmitted to the monitoring network to realize the test and monitoring.3. Composing and structure of the systemThe safety monitoring system includes the ground part
49、 and the underground part (seen in Figure 2).The products in the system adopt the sap hanging design (Tan, 2007) to ensure the normally and continually running of the system in the severe environment and offer power supply for 13 hours after power-down.The underground part and the ground part adopt
50、the RS-485 serial interface standard communication and the RS-232 standard serial interaction to connect with the transmission network. The data conversion interface is mainly composed by the power supply board, signal conversion board and safety bolt, and it is placed on the mouth of the mine, and
51、it is mainly used to ensure the information exchange between the underground monitoring points and the ground monitoring center, so the system needs not the RFID and A/D converter. Figure 3 is the exchange of the communication signals between the ground and the underground.3.1 Underground partThe un
52、derground part is the core part of the monitoring system, and it includes the fieldbus and a series of substations which are used to monitor and control the personnel. The fieldbus is the network which connects the substation and transmits information. Some substations are used to position the under
53、ground workers and equipments real time. The positioning mode of the personnel and equipments is the signal strength monitoring method, and when the E-tag carried by one worker is near certain positioning station, the signals acquired by the station are strong, so we can judge the position of the ta
54、g, and when the E-tag is in the superposition region of two stations, the signal strengths of two station will be different, and we can judge the position of the tag by comparing the strengths of the signals. Other substations are mainly composed by sensor, A/D converter, micro-controller and RFID m
55、odule, and they can monitor the harmful gases real time and acquire the transmission of the information, and when the concentration of the harmful gases exceeds the safety value, the ground work platform and the underground fixed monitor point emit the alarm simultaneously. The substation in the und
56、erground part adopts the wire communication, the serial interface and the RS-232 serial data interface standard, and the bus transmission and the serial interface are used for the future expansion of the system function.3.2 Ground partThe ground part mainly includes the management operation system,
57、and it is the base of the whole safety monitoring system, and its main functions are to complete the information acquirement, real-time processing and storage of the check point. The information from the underground include not only the concentration of the harmful gases, but the information about t
58、he underground personnel and equipment, and these large-size data are all stored in the database through compression as the base of the monitoring and controlling.4. ConclusionsIn this article, we applied the RFID technology in the coal mining management, and established an underground safety monitoring system with integrality, real-time and flexibility, which could automatically alarm when dangers happened and enhanced the search and rescue efficiency. The system could manag
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