馬鴻娟外文資料翻譯
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1、 畢業(yè)設(shè)計(jì)(論文)外文資料翻譯 題 目: 移動(dòng)通信系統(tǒng)的進(jìn)化與發(fā)展 Evolution and Development Toward Mobile Commuinication Systems 院系名稱: 信息學(xué)院 專業(yè)班級(jí): 電科1002 學(xué)生姓名: 馬鴻娟 學(xué) 號(hào): 201048360229 指導(dǎo)教師: 咸金龍 教師職稱: 講 師 附 件: 1.外文資料翻譯譯文;2.外文原文。
2、 2014年3月10日 附件1:外文資料翻譯譯文 一、 引 言 互聯(lián)網(wǎng)是將分布在世界各地的計(jì)算機(jī)連接起來(lái)的巨大網(wǎng)絡(luò),,發(fā)送數(shù)據(jù)使用基于TCP / IP堆棧的分組交換技術(shù)。通過(guò)增強(qiáng)功能的有線/無(wú)線協(xié)議在通信技術(shù)和基礎(chǔ)設(shè)施領(lǐng)域取得持續(xù)不斷的提高,互聯(lián)網(wǎng)已經(jīng)取得了巨大的成功和聲望。在過(guò)去的時(shí)間里伴隨著在溝通模式(有線和無(wú)線)上的成長(zhǎng)與加速進(jìn)展和廣泛要求閑置產(chǎn)能和連通性,互聯(lián)網(wǎng)幾乎在每個(gè)方面頻繁修改和變更。同時(shí)支持互聯(lián)網(wǎng)的設(shè)備也是一個(gè)難以置信的進(jìn)步在無(wú)線和移動(dòng)技術(shù)領(lǐng)域。因?yàn)樵谶^(guò)去的幾年中,無(wú)數(shù)的快速改進(jìn)見(jiàn)證了移動(dòng)和無(wú)線技術(shù)領(lǐng)域的發(fā)展,同時(shí)這兩中技術(shù)服務(wù)需求大大上升,用戶驅(qū)動(dòng)的服務(wù)
3、需求徹底變革了全球電信的精神和本質(zhì)(弗里曼和羅杰,2004),并且已經(jīng)形成了現(xiàn)代電信領(lǐng)土。這研究工作,我們給出了不同代的移動(dòng)通信系統(tǒng)的詳細(xì)調(diào)查,我們的目的不是選擇一個(gè)最好的,因?yàn)樵S多技術(shù)仍在發(fā)展。我們有期望更詳細(xì)的了解不同的情況下不同技術(shù)將更好地工作和性能退化的來(lái)源。 本文的其余部分組織如下。第2節(jié)中,我們概述不同的無(wú)線技術(shù)。在第3節(jié)中,我們比較分析移動(dòng)通信系統(tǒng)(即前幾代1 G,2G和3G)和逐步分析其特點(diǎn),闡述了各種幻想未來(lái)利用3G和4G技術(shù)。最后在第四部分,我們給出了結(jié)論。 二、回顧文獻(xiàn) 2.1介紹1G、2 G、3 G和4G 無(wú)線空中接口序列意味著它在世界是最常見(jiàn)的標(biāo)準(zhǔn)。它們幾乎
4、通過(guò)所有的代(即1、2、3、4G)的開(kāi)發(fā)和研究被結(jié)構(gòu)化,包括各種派生或交替使用的術(shù)語(yǔ)來(lái)描述它們。 1G:1 G的技術(shù)是模擬(只能)即1 G無(wú)線手機(jī)行使模擬技術(shù)。這些設(shè)備是笨重和裸露并且可靠,但是他們有效 2G:2G的技術(shù)是數(shù)字——在美國(guó),主要設(shè)備和服務(wù)是數(shù)字。數(shù)字蜂窩服務(wù)有很大的全球部署。他們?nèi)〉昧艘粋€(gè)重要的進(jìn)步在聲音的質(zhì)量上(因?yàn)槟M信息非常受到失真比起數(shù)字信息)并且增強(qiáng)能力,因?yàn)檎Z(yǔ)音電話以更有效的方式可以被多路復(fù)用。它提供了不同的服務(wù),如某種程度的web訪問(wèn)設(shè)備,數(shù)字語(yǔ)音通話和短消息服務(wù)(SMS)。GSM、時(shí)分多址和碼分多址是幾個(gè)手機(jī)標(biāo)準(zhǔn)的2G技術(shù)。 3G:3 G(史密斯.2
5、000年)的無(wú)線技術(shù)致力于提供合理迅速的無(wú)線通信來(lái)支持更有用的服務(wù),如數(shù)據(jù)、視頻和多媒體以及聲音。無(wú)線移動(dòng)通信技術(shù)在目前的形式通常被2.5G(Gozalvez .2001年)(稱為邊緣技術(shù)),但只是3 G網(wǎng)絡(luò)現(xiàn)有的權(quán)利是美國(guó)EVDO & UMTS(HSPDA)并且由(Sprint / Verizon)和Cingular運(yùn)營(yíng)商相對(duì)提供。3G把未來(lái)發(fā)展深入到業(yè)務(wù)/私人無(wú)線技術(shù),特別是在移動(dòng)通信領(lǐng)域和一些預(yù)期的功能以及特性的3G系統(tǒng): ?增強(qiáng)功能,為多媒體通信(即數(shù)字?jǐn)?shù)據(jù)和語(yǔ)音、視頻和遠(yuǎn)程控制系統(tǒng)) ?支持利用到所有先進(jìn)的模式(即郵箱、傳真、尋呼、移動(dòng)電話、上網(wǎng)、視頻會(huì)議等) ?廣泛的帶寬和高
6、速能力(超過(guò)2 Mbps) ?提供靈活的路由(中繼器、衛(wèi)星、局域網(wǎng)等) 4G:4G(Woerner,2001)的無(wú)線技術(shù)還在繼續(xù)進(jìn)行,并且迎接即將到來(lái)的無(wú)線設(shè)備標(biāo)準(zhǔn)。區(qū)別4 G和3 G技術(shù)的關(guān)鍵是提高數(shù)據(jù)的傳輸速率和安全,就像它是3 G超過(guò)2.5 g或2G。4G被期待提供更多的增強(qiáng)版本就像當(dāng)初相3G所承諾的也要做出相同的進(jìn)步 一樣(如。,提高多媒體、視頻直播,全球訪問(wèn)和通過(guò)各種各樣的設(shè)備實(shí)現(xiàn)全球可移植性)。通常,1G被定義為是時(shí)間跨度十到十五年的技術(shù)發(fā)展結(jié)果,因此,4 g將轉(zhuǎn)向在2010期開(kāi)始的任何部署,假設(shè)3 G開(kāi)發(fā)涵蓋了2000 - 2010年期間。因而通過(guò)利用OFDM(羅伯遜,199
7、9)(正交頻分復(fù)用)技術(shù)4 G將為顧客提供一流的視頻和音頻點(diǎn)播,進(jìn)而能夠更好的分配網(wǎng)絡(luò)資源,并且多個(gè)客戶端利用多個(gè)頻道同時(shí)進(jìn)行。不同于3 G網(wǎng)絡(luò)分組交換和電路交換的混合網(wǎng)絡(luò),4G將僅僅基于分組交換就有可能連接整個(gè)世界無(wú)論地球的表面還是在其以上。 2.2碼分多址(CDMA) CDMA(Gharavi .2001年)是一種多路復(fù)用并且通過(guò)頻率或時(shí)間不共享通道的 技術(shù)(如FDMA或TDMA),然而它在編碼信息的一些獨(dú)特的相關(guān)代碼,每個(gè)頻道和利用動(dòng)態(tài)干擾效應(yīng)的一個(gè)特定的代碼復(fù)用。此外,它指的是一個(gè)數(shù)字蜂窩電話系統(tǒng),利用這些多重存取方案。CDMA已經(jīng)被應(yīng)用于許多通信系統(tǒng)(即Omni-TRACS衛(wèi)星系
8、統(tǒng)(弗里曼.2004年)和全球定位系統(tǒng)(GPS)。圖1提供了一個(gè)通用架構(gòu)的一個(gè)通信CDMA系統(tǒng)。 2.3寬帶碼分多址(WCDMA) WCDMA是一種寬帶數(shù)字無(wú)線接入技術(shù)。1998年,歐洲電信標(biāo)準(zhǔn)協(xié)會(huì)(ETSI)用它來(lái)支持3 G多媒體應(yīng)以此來(lái)進(jìn)行寬帶數(shù)字電臺(tái)訪問(wèn)。WCDMA提供了一個(gè)創(chuàng)新服務(wù)能力,并且提高網(wǎng)絡(luò)速度,同時(shí)與2 G技術(shù)相比服務(wù)成本更低。它是由世界十大供應(yīng)商中八個(gè)優(yōu)先提供的3G標(biāo)準(zhǔn)。運(yùn)營(yíng)商可以輕易地從GSM進(jìn)步到WCDMA,以后儲(chǔ)蓄投資就可以通過(guò)再利用GSM設(shè)置和服務(wù)。 2.4全球移動(dòng)通訊系統(tǒng)(GSM) 當(dāng)代移動(dòng)通訊最受人歡迎的標(biāo)準(zhǔn)是GSM(巴赫.2000)。世界各地超過(guò)2
9、0億人(超過(guò)250個(gè)國(guó)家/地區(qū))使用GSM提供的服務(wù)。它與它的發(fā)展開(kāi)始相區(qū)別在于集中性演講和信號(hào)通道的數(shù)字化,表明它是假定為2G移動(dòng)通信系統(tǒng)。目前它由第三代項(xiàng)目提出已經(jīng)變成一個(gè)開(kāi)放標(biāo)準(zhǔn)的GSM。根據(jù)消費(fèi)者的判斷,GSM系統(tǒng)的主要優(yōu)勢(shì)已經(jīng)由高質(zhì)量的數(shù)字語(yǔ)音通道和低價(jià)格替代為打電話(如SMS)并且形成了網(wǎng)絡(luò)運(yùn)行商的未來(lái)。當(dāng)開(kāi)放標(biāo)準(zhǔn)擴(kuò)充兼容性時(shí)它便成為潛在的設(shè)備。此外,這些標(biāo)準(zhǔn)允許網(wǎng)絡(luò)提供商提供漫游設(shè)施這意味著客戶可以在世界各地利用手機(jī)。圖2說(shuō)明了GSM系統(tǒng)的總體架構(gòu)。 2.5通用分組無(wú)線服務(wù)(GPRS) GSM移動(dòng)電話用戶受益于一個(gè)新的移動(dòng)數(shù)據(jù)服務(wù)叫做GPRS(布拉頓.2001)。GPRS是2
10、 G向3 G系統(tǒng)的轉(zhuǎn)化的命令式進(jìn)化。在GSM網(wǎng)絡(luò)它通過(guò)利用空閑的TDMA頻道提供了一個(gè)合理的數(shù)據(jù)傳輸速度,。它提供了友好的計(jì)費(fèi)系統(tǒng)和高容量通道并且減少了呼叫建立時(shí)間。GPRS系統(tǒng)優(yōu)化分組交換數(shù)據(jù)網(wǎng)絡(luò)并且是完全從手機(jī)網(wǎng)絡(luò)過(guò)渡的電路交換,分組交換。圖3描述了GPRS系統(tǒng)的總體架構(gòu)。GPRS提高GSM數(shù)據(jù)服務(wù)提供: ?使用GSM語(yǔ)音以合理的低成本支持靈活的共存等提供各種各樣的服務(wù) ?提供叢發(fā)性交通支持 ?提供快速訪問(wèn)時(shí)間 ?有效利用網(wǎng)絡(luò)和無(wú)線資源 三、技術(shù)比較 3G下一步是超越2 G標(biāo)準(zhǔn)發(fā)展(例如CDMA和GSM)。3 G的重要方面包括技能合并蜂窩移動(dòng)網(wǎng)絡(luò)和互聯(lián)網(wǎng),多媒體通過(guò)提高射程和
11、語(yǔ)音服務(wù)質(zhì)量以及數(shù)據(jù)服務(wù)將應(yīng)用程序添加到一個(gè)無(wú)線電腦/移動(dòng)電話。在不久的將來(lái), 4G是即將到來(lái)的無(wú)線網(wǎng)絡(luò)技術(shù),它將實(shí)現(xiàn)3G網(wǎng)絡(luò)到4G網(wǎng)絡(luò)的轉(zhuǎn)換。 四、結(jié)論 在本研究工作中,我們已經(jīng)調(diào)查了四個(gè)無(wú)線技術(shù)即1 G,2G、3 G和4 G。我們得出結(jié)論,4G移動(dòng)技術(shù)于其能力和對(duì)世界的無(wú)線移動(dòng)通信靈活性將刺激用戶對(duì)寬帶無(wú)線應(yīng)用程序的興趣。幾乎可以肯定的說(shuō)無(wú)線移動(dòng)技術(shù)滿足了很多著眼于無(wú)線世界的用戶。最后報(bào)告闡述了在過(guò)去的不同的移動(dòng)通信技術(shù)和他們的發(fā)展歷程以及發(fā)展走向4G通信系統(tǒng)。他們互相詳細(xì)的對(duì)比討論以便能更好地對(duì)向4G通信系統(tǒng)進(jìn)化和發(fā)展進(jìn)行認(rèn)識(shí)和了解。在本研究工作中,我們以讀者可能獲得最大范圍話題的方
12、式試圖收集盡可能多的信息。 附件2:外文原文 Evolution and Development Toward Mobile Commuinication Systems 1 . Introduction The Internet is the network of large-scale group of connected computers around the world that sends out data using packet switching technique based on the TCP/IP stack. (Wright and Steven, 1995
13、) With a continuous improvement in the field of communication technologies (ITU-R, 2000) and infrastructures by means of enhancing the functionalities of the wired/wireless protocols, the Internet has achieved the massive success and popularity. Over the time with the growing and accelerating progre
14、sses in communication patterns (wired and wireless) and wildly demands for spare capacity and connectivity, the Internet in almost every aspect frequently experiences modifications and changes in order to bring up-to-date. Along with the requirements supporting the Internet has been an implausible p
15、rogress in the field of wire-less and mobile technologies. Since during the last few years, a countless fast improvements have been observed in the area of mobile and wireless technologies, and these two drastically rising user-driven service demands have significantly and intensely revolutionized
16、the spirit and nature of worldwide telecommunications (Freeman and Roger, 2004) inthese millenniums and have developed the modern telecom territory. In this research work, we present the detail survey of the different generations of the mobile communication systems and our purpose is not to choose a
17、 victor because many of the technologies are still in progress. Somewhat, we anticipate to get in detail knowledge of the situations wherein different technologies would work better, and the sources of performance degradation. The remainder of this paper is structured as follows. In Section 2, we
18、 give an overview of the different wireless technologies. In Section 3, we present the comparative analysis of 4thgeneration mobile communications system to the earlier generations (1G, 2G and 3G) and progressively analyze their characteristics, and elaborate the various visions for the future utili
19、zation of 3G and 4G technologies. Finally in Section 4, we present the conclusions of this work. 2. Review of Literature 2.1 Introduction to 1G, 2G, 3G and 4G The list of wire-less air interface protocols which follows signifies the most familiar standards in exercise around the world nowadays
20、. They’re structured almost by means of generations (i.e., 1stG, 2ndG, 3rdG and 4thG) of development and include various derivations or alternate terms used to describe them. 1G: 1G of technology was analog (voice-only) i.e., 1G wireless phones exercised analog technology. These devices were weight
21、y and exposure was unreliable, however they effectively 2G: The 2G of technology is digital – in the United States, mostly devices & services are digital. Digital cellular services are vastly deployed world-wide. They presented a significant development in the quality of voice (since analog infor
22、mation is much subject to distortions as that of digital information) and enhanced capacity as well, as voice calls in a more efficient way can be multiplexed. It provides the different services like some degree of web-access facility, digital voice calling and short message service (SMS). The GSM,
23、TDMA and CDMA are the few cell phone standards of 2G. 3G: The 3G (Smith et al., 2000) of wireless technology is committed to provide reasonably speedy wireless communication to support more useful services such as data, video and multimedia as well as voice. The wire-less mobile communication tech
24、nology in it’s present form is often known as 2.5 G (Gozalvez et al., 2001) (called EDGE technology) but simply existing right networks of 3G in the United States are EVDO & UMTS (with HSPDA) offered by (Sprint/Verizon) and Cingular carriers, respectively. The 3G offers next to future advances into
25、the business/private wire-less technology, particularly in a field of mobile communications and some expected capabilities and features of 3G systems are: ? Enhanced features for multimedia communications (i.e., digital data & voice, video & remote controls system) ? Supporting to utilize onto a
26、ll advanced modes (i.e., electronic-mail, fax, paging, cellular-telephones, web-surfing, video-conferencing etc) ? Extensive bandwidth & high-speed capability (upwards of 2 Mbps) ? Providing flexibility for Routing(repeaters, satellites, LANs etc) 4G: The 4G (Woerner, 2001) of wireless technolo
27、gy is still underway and stands to be the upcoming wireless devices standard. The key difference between 4G and 3G technologies is the improved data transfer rates and security, like it is for 3G over 2.5G or 2G. The 4G is looked forward to offer more enhanced versions of the same advancements promi
28、sed by 3G (e.g., improved-multimedia, video-streaming, global-access and worldwide-portability through all kinds of devices). Normally, a generation is defined by the result of technology grows over a time-frame of ten-to-fifteen year, hence, 4G would turn to whatever is deployed in the 2010 period
29、onward, supposing 3G exploitation covers the 2000-2010 period. Somewhat, 4G would provide customers with on demand first-class video and audio by utilizing OFDM (Robertson, 1999) (Orthogonal Frequency Division Multiplexing) technique and would able to better allocate network resources to multiple cl
30、ients by making use of multiple channels simultaneously. Unlike the 3G networks which are a mixture of packet-switching and circuit-switching networks, 4G (Hui et al., 2003) will be based on packet switching only and might actually connects the whole world and be operable from any place above or on
31、the surface of the globe. 2.2 Code Division Multiple Access (CDMA) CDMA (Gharavi et al., 2001) is a type of multiplexing which doesn’t share the channels by frequency or time (like FDMA or TDMA), however it en-codes information by some unique codes related to each channel and exploits dynamic
32、 interferences effects of a particular code to do multiplexing. In addition, it refers to a digital cellular telephony system which utilizes these multiple access schemes. CDMA has since been applied in a number of communication systems (i.e., Omni-TRACS satellite system (Freeman et al., 2004) and G
33、lobal Positioning System (GPS) (Hatch et al., 2002)). Figure 1 presents a general architecture of a CDMA system. 2.2.3 Wideband Code Division Multiple Access WCDMA (Bidaud, 2001) is a type of wideband digital radio-access technology. In 1998, the European Telecommunications Standard Institute (ET
34、SI) used it to support 3G multimedia applications for wideband digital radio-access. WCDMA offers an innovative service capability, improved network speed and low-cost for services (data and voice) compared to 2G technologies. It is the foremost worldwide 3G-standard preferred by eight of the world'
35、s ten largest service-providers. Operators can softly progress from GSM on the way to WCDMA, hence saving investments via reutilizing the GSM setups and services (Gozalvez et al., 2001). 2.4 Global System for Mobile Communications For mobile communications the most well-liked standard in the wor
36、ld is GSM (Bach, 2000). More than 2-billion people across the world (over 250 countries/territories) use the services offered by the GSM. It distinguishes much from its ancestors given that collectively speech and signaling channels are digital, indicating that it is assumed as the 2G mobile communi
37、cation system. GSM now becomes an open standard that is presently proposed by the 3GPP. According to the consumer judgment, the GSM system’s main advantage has been high-quality digital-voice channels and reduced price alternative to make calls (like SMS) and from a network operator prospective, it
38、 has been the potential to employ equipments as of various providers as the open standards accepts simpleinter-compatibility. In addition, these standards permitted networks providers to allow roaming facilities that means the customers can utilize their phones whole across the world. Figure 2 illu
39、strates the general architecture of a GSM system. 2.5 General Packet Radio Service (GPRS) The GSM mobile phones users get benefit from a new mobile data service called GPRS (Bratton et al., 2001). The GPRS is an imperative step in the evolution of 2G mobile systems towards 3G systems. It offers
40、a reasonable data transfer speed, via utilizing unoccupied TDMA channels in the GSM networks. It provides friendly billing system, high capacity channel and reduced call setup time. The GPRS system is optimized for the packet switched data networks and is transition totally from the cellular network
41、 of circuit switched to packet switched. Figure 3 describes the general architecture of a GPRS system. GPRS improves GSM data services providing: ? offer variety of services at reasonably low-cost to support flexible co-existence using GSM voice ? provide bursty traffic support ? possible
42、support for connectivity to the Internet ? providing fast-access time ? utilize network and radio resources efficiently 3. Comparison of Technologies The 3G is the next step leaving beyond the 2G standards (for instance CDMA and GSM). The important aspects of 3G consist of the skills to
43、merge the cellular mobile networks with the internet, adding multimedia applications to a wirelesscomputer/mobile phone by improving the range and QoS of voice and data services. In near future, the 4G is the upcoming technology of wire-less networks which will switch from 3G to 4G networks. 4. C
44、onclusions In this research work, we have surveyed four wireless technologies namely 1G, 2G, 3G and 4G. We conclude that the 4G mobile technologies will stimulate subscriber interest in broadband wireless applications because of its ability and flexibility towards the world of wireless mobile comm
45、unications. A concentrated effort seems to categorize how wire-less mobile technologies can accompaniment a more user focused world of wire-less. Finally the report elaborates the different Mobile Communication Technologies that have been developed in the past and their evolution and development tow
46、ards 4th generation communication systems. Their detail comparison with each other has been discussed to have a better knowledge and understanding about the technological advancement made towards the evolution and development of 4thgeneration communication systems. In this research work, we have tried to gather as much information as possible and assemble it in such a manner that the reader can gain maximum knowledge of the topic.
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