光纖通信外文資料及翻譯(適用于外文翻譯+中英文對(duì)照)-文庫吧
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【正文】 議設(shè)計(jì)為相切 環(huán)，以調(diào)度中心為切點(diǎn)；如果局調(diào)度中心局域網(wǎng)偏離網(wǎng)絡(luò)地理中心，建議設(shè)計(jì)為相交環(huán)，由于調(diào)度中心不在交點(diǎn)，為了環(huán)間可靠轉(zhuǎn)接，各環(huán)相交至少兩點(diǎn)，互為保護(hù)路由。 6 結(jié)束語 在實(shí)際的配網(wǎng)自動(dòng)化的通信系統(tǒng)，必須構(gòu)建一個(gè)成本低、收效高的雙向通信系統(tǒng)，用可以接受的費(fèi)用在可靠性和信息流量方面提供非常高的性能。同時(shí)，由于配電網(wǎng)自動(dòng)化系統(tǒng)所要完成的功能太多而系統(tǒng)復(fù)雜，采用單一的通信系統(tǒng)來滿足所有的功能需要是不現(xiàn)實(shí)的，也是不經(jīng)濟(jì)的。因此，在配電網(wǎng)自動(dòng)化系統(tǒng)中，要應(yīng)用多種通信方式，按綜合的經(jīng)濟(jì)技術(shù)指標(biāo)而選取其中最優(yōu)的組合。在電力系統(tǒng)中 較常用的通信方式還有一點(diǎn)多址數(shù)字微波、數(shù)傳電臺(tái)、無線擴(kuò)頻、專線電纜、郵電本地網(wǎng)、載波、擴(kuò)頻載波等，可供組網(wǎng)時(shí)選擇。 l附件 2：外文原文（復(fù)印件） Optical fiber munication in power distribution automation applications onpaper1 Foreword The first phase in the evolution of munication works is dominated by thewide spread of telephony and covers over 90 years . However the telegraph preceded thetelephone by more than 30 years and the teletypewriter by half a century . In1844Samuel Morse the telegraph’s inventor sent the first telegraph message fromWashington . to his coleague Afred Vail in Baltimore Maryland. Shortly after theinvention of the telephone by Alexander Grahan Bell in 1876 it was realized thattelephone wires had to converge on central points where telephonetotelephoneconnections could be made .These points were manual switchboardStaffed by operator .This was followed by the introduction of electromechanicalswitching and in 1889Almond invented the first twomotion stepbstepswitch. The golden age of automatic telephony occurred after Word War ∏ when theentire longdistance work was automated .The invention of the transistor spurred the application ofElectronics to switching systems and led to the deployment of the first electronicswitching in the late 1950s . Electronic switching made it possible to design and buildswitches with greater capacity. The second phase of working which occurred in the 1960s included three majormilestones:software switching digital transmission and satellite The third phase of the evolution of munication works occurred in the 1970s andis characterized by the introduction of data works and packer switching achieve patibility between puters and packetswitched work theinternational Telegraph and Telephone Consultative Committee CCITT from the Frenchacronym established a wordstandard protocol called in 1976. This phase ofworking is also characterized by the introduction and wide acceptance of local areaworksLANs. The invention of the laser which stands for light amplification bysimulated emission of radiation in 1959 led to major technical developments in the fieldof optical munication. 1970 Corning Glass Works r
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