【正文】 advanced science and technology activities in Dalian youth units。 schools ”for the school mission and on behavior, raising habits, pursuingdevelopment, hing research,benefit, the high quality。從圖中可以看出，某一載 波可在兩個不同的地理區(qū)域重復使用，只要這兩個地區(qū)離的足夠遠，相互之間的 干擾足夠小。為了盡量提高抗干擾的能力，無線接口使 用了一系列技術(shù)。小區(qū)的形狀是不規(guī)則的，這取 決于是否有現(xiàn)成的基站，地理地形，無線電信號傳播中存在的障礙，等等。為了最有效地利用帶寬，系統(tǒng)設計的目的是通過基站的服務區(qū)到周邊小區(qū)，理論上是一個正六邊形。質(zhì)量改進的原因 還在于使用先進的技術(shù)如電源控制或跳頻改善了無線連接的控制,，傳播條件的適應性等。請注意，無線電頻率復用也取得了一定增益，這 也已用于模擬系統(tǒng)。此外，電話費用也降低了，因為GSM 是國際標準，生產(chǎn)數(shù)量大，競爭水平高。既使當用 戶從一個國家移動到另一個國家，電話也可以使用同一個個人號碼。和這些系統(tǒng)相比，GSM 提供的更重要的第二代數(shù)字系統(tǒng)主要優(yōu)勢 體現(xiàn)在： 〃標準化； 〃容量； 〃質(zhì)量； 〃安全。完成提供功能和接口描述的 功能個體在系統(tǒng)中都有定義。隨著美國后來在GSM 領(lǐng)域制造了一個詞條PCS1900 作為GSM 的拓展,GSM 系統(tǒng)已發(fā)展至 各大洲,并且縮寫詞GSM 現(xiàn)在已可以代表移動通信的全局系統(tǒng)。商業(yè)服務在1991 年中期開始了，截至1993 年有 36 個GSM 網(wǎng)絡在22 個國家誕生了。每個國家開發(fā)了它自己的系統(tǒng)，在設備和操作 上是互不相容的。ISDN patibility In 1989, GSM responsibility was transferred to the European Telemunication Standards Institute(ETSI), and phase I of the GSM specifications were published in service was started in mid1991, and by 1993 there were 36 GSM networks in 22 standardized in Europe, GSM is not only a European 200 GSM networks are operational in 110 countries around the the beginning of 1994, there were million subscribers worldwide, which had grown to more than 55 million by October North America making a delayed entry into the GSM field with a derivative of GSM called PCS1900, GSM systems exist on every continent, and the acronym GSM now aptly stands for Global System for Mobile developers of GSM chose an unproven(at the time)digital system, as opposed to the thenstandard analog cellular systems like AMPS in the United States and TACS in the United had faith that advancements in pression algorithms and digital signal processors would allow the fulfillment of the original criteria and the continual improvement of the system in terms of quality and over 8,000 pages of GSM remendations try to allow flexibility and petitive innovation among suppliers, but provide enough standardization to guarantee proper interworking between the ponents of the done by providing functional and interface descriptions for each of the functional entities defined in the General Concepts Analog Versus Digital Telephony Systems Firstgeneration systems were the early 1980s these underwent rapid development in the NMT system was used by all the Nordic countries, and the TACS system in the United Kingdom and Italy, there was a variety of systems and no patibility among with these systems, the main advantages offered by GSM, which is the most important of the secondgeneration digital systems, are: Support for international roaming 社保、教育、技術(shù)研究，則會消除人們存錢的預防養(yǎng)老動機從而擴大消費，利于中國經(jīng)濟可持續(xù)發(fā)展。s GDP ranks the second in the world, but per capita GDP still ranks out of hundreds in the world, the poor is the WuhanGuangzhou highspeed railway was used, the original passenger trains were stopped, which means lowiner will be forced to choose highspeed rail and accept the high action hasimpair interests of the low class people, and the corruption problem will be prone to easily during the process of 。中國的 GDP 總量 高居世界第二，但人均 GDP 在世界的排名卻還在百名開外，窮人還是絕大多數(shù)。中國第一條高 鐵客運專線——從北京到天津，它在 2008 年 8 月通車后一年就虧損了 7 個億。這就意味著要加大對交通基礎(chǔ)設施的投資，但是政府在加大交通基礎(chǔ)設施投資力度的同時，用于改善民生的措施實際卻在相對地減少。s enjoy what joy remains 今宵別夢寒Tonight39。第一篇：《送別》英文翻譯送別A Valediction李叔同by Li Shutong 長亭外Beyond the distant pavilion 古道邊Beside the ancient road 芳草碧連天Jade green and fragrant, high grass joins the sky 晚風拂柳笛聲殘 Evening breeze sways dripping willows dying flutenotes linger still 夕陽山外山On the hill behind the hill, the sun sets 天之涯地之角To the ends of the earth and corners of the seas 知交半零落Half our friends are scattered 一斛濁酒盡余歡With a scoop of thick wine let39。s cold dreams shall be held at bay長亭外古道邊On the ancient road by the Farewell Pavilion，芳草碧連天green grass stretches far into the With willow trees in evening wind and sounds of a staccato flute, 夕陽山外山the setting sun sil