第一篇：英文翻譯

他的研究結果并不明朗，往往揭示出一個微弱的甚至是消極的關于留存收益的FDI與稅務的反映機制。這項研究明顯對哈特曼模型投出了質疑，但一直沒有大的動作嘗試用更好的數據或方法進行重新估計。

文獻中確實體現了Slemrod（1990）的想法，他認為處理雙重征稅的政策可能會影響稅收反應。常見的區別是不對母國以外的收入進行征稅的國家之間，免征國外賺來的收入的納稅義務，以及對母公司潛在的應納稅額收取的全球性稅務，但可能會采取多種方式來處理國外收入來避免跨國公司的雙重征稅。處理雙重征稅的問題有兩個標準的方法，為本國提供信貸或者扣除由跨國公司取得的國外納稅收益。

當研究人員開始研究1986年美國稅制改革對于在美國的外來直接投資的顯著性影響時，這些稅務處理辦法對于影響FDI和稅收分析的潛力，在研究文獻中起到了至關重要的作用。斯科爾斯和歐勝（1990）推測，當美國的稅率增加，美國在全球范圍的跨國公司所產生的FDI可能會增加！這看似有悖常理的概念來自于認識到了信用體系，例如，跨國公司不會在全球征稅系統下看到應納稅額有所增加。在另一方面，美國國內投資者（屬地稅制下的跨國公司）將承擔增加的美國稅項負債的全面沖擊。隨著公司在美國投標了相同的的資產，全球稅收跨國公司將會變得有利并且投入更多。盡管斯科爾斯和歐勝（1990）用很簡單的統計檢驗表明，美國外國直接投資自1986年以后的上升沒有受到其它因素的控制，但是斯文森（1994年）對斯科爾斯和歐勝的假設做了更仔細的檢查，通過對1986年的改革對不同產業FDI產生的不同影響進行檢測，這些產業在改革后稅率都發生了變化。具體來說，斯文森檢查了從1979年到1991年行業面板數據，利用從1986年的稅制改革后行業稅率的變化，發現FDI確實隨著更大的平均稅率增加而增加，尤其是全球征稅的國家。斯文森的研究一個令人擔憂的問題是，他確定了斯科爾斯和歐勝采用平均稅率數據進行檢測時結果是接受假設，但使用實際稅率則是拒絕原假設。奧爾巴赫和哈塞特（1993）提供了推翻斯科爾斯和歐勝假設的進一步證據，他們通過開發FDI模型來預測美國的投資類型，稅制改革應該對其進行支持為了使屬地納稅的跨國公司對抗全球納稅的跨國公司。特別是，他們的模型顯示，屬地稅收跨國公司應該將更多的精力放在激勵合并與收購（M＆A）的外國直接投資，而全球稅收跨國公司應該已經從這樣的FDI投資新設備的情況下氣餒。這些數據似乎表明，1986年美國稅法改革后外商直接投資的大幅增加，是由于跨國公司從全球稅收國家（主要是日本和英國）推進對外直接投資。

因此，在很多方面，1986年的稅制改革對FDI的影響到今天都是一個開放性問題。然而，盡管這個特定的問題如今已經有些過時了，但是給母公司提供信用的全球稅收制度國的FDI應該相對而言對稅率不那么敏感這個話題仍然是持續的熱點。海恩斯表示（1996年）對它做出了最好的表達，根據現存文獻檢測了是否國家級稅會影響美國內區域的FDI，從而創造性地提出了屬地納稅對抗全球納稅的處理辦法。以往的研究探討國家稅收對于國家FDI的分布的影響，結果并不明顯（參見例如，考夫林，Terza和Arromdee，1991）。像聯邦稅，跨國公司根據他們在母國面臨屬地納稅還是全球納稅可能會對國家級稅有不同的反應。海因斯（1996）的實證策略是調查FDI在美國各州的分布，并且研究比較“非信用體系”的狀態下的外國投資者相對于“信用系統”下的外資投資者FDI的稅收敏感度。他發現，隨著稅率高1％，非信用體系投資者FDI的減少比信用體系投資者FDI的減少多 9％。

綜上所述，文獻精細的指出了當考慮到稅收對FDI的影響時，資料多的用不了。跨國公司在母國和東道國都遭遇了大量不同級別的稅率和處理雙重征稅的政策，這能極大的改變稅收對鼓勵跨國公司投資的影響。正如上文所提到的，經驗方法和數據樣本相差甚遠，因此稅（以及在美國1986年的稅收改革之類的）在多大程度上影響FDI仍然是顯著的問題。證據似乎更有力的說明了，一個跨國公司在客國申報納稅而形成的處理國外稅的信用系統是相對無關緊要的。

文獻中還存在其他的弱點需要解決。首先，所有上述考察（最好）產業層面的數據模型的研究通常是屬于公司層面的活動。這可以通過依靠理論來解釋經驗證據來制造問題。這方面最明顯的例子是使用平均稅率為利率變量，這在變量設置上是一個完全的錯誤。平均或實際稅率是否作為稅務義務的的測度很少被討論，但正如作為例證的斯文森（1994）研究所說，它對FDI會產生十分不同的影響。

文獻也只是最近才開始研究除企業所得稅以外的其他稅。例如，德賽，弗利和海因斯（2004）最近的工作論文提出的證據表明，間接營業稅對FDI的影響與企業所得稅對FDI的影響是一定范圍內是相同的。與此類似，雙邊國際稅收協定對FDI的影響直到最近仍然是未被開發的實證課題。關于談判減少國家在其他事項上的代扣所得稅的稅收協定有成千上萬個。沃德-Dreimeier（2003年）和Blonigen和Davies（2004）發現沒有證據表明這些條約在任何顯著的方面影響FDI的活動.3.3機構

機構的質量有可能是影響FDI活動的一個重要的決定因素，特別是對于由于各種原因而較不發達的國家。首先對資產欠缺法律保護增加了企業進行投資的資產不太可能征收的機會。機構質量差需要運作良好的市場（和/或貪污），這就增加了做生意的成本，也就減少了FDI的活動。最后，在一定程度上機構質量差導致基礎設施差（即公共產品），當FDI確實進入市場則預計盈利能力會下降。

盡管這些基本假設是無爭議的，但估計機構對外國直接投資的影響幅度是困難的，因為沒有任何準確的機構測量。大部分措施是一個國家的政治，法律和一些經濟體制的復合指數，根據官員或熟悉國家機制的商人的調查結果制定。由于受訪者來自不同的國家導致國家間的可比性值得商榷。另外，機構通常會保持長久，因此隨著時間的推移在一個國家內很少會發生有意義的變化。

由于這些原因，盡管跨國FDI研究通常包括機構以及或者貪污腐敗的措施，但并不經常把它作為分析的重點。魏的論文（2000年;2000B）是一個例外，表明各種腐敗指數與FDI有著強烈的負相關性，但其他的研究中沒有發現這樣的證據（如惠勒和么，1992年）。海因斯（1995）提供了一個有趣的“自然實驗”的方法，通過研究1977年的美國反海外腐敗法中關于處罰美國跨國公司賄賂外國官員的規定。他估計在法案實行的之后一段時間后會發現該法案對FDI的負面效應。這種自然實驗分析為將來提出更令人信服的證據帶來了希望，盡管發現這樣的天然實驗是非常困難的。3.4 貿易保護

外國直接投資和貿易保護之間的假設聯系被大多數貿易經濟學家看作是還算明朗的。即高貿易保護應該讓企業更有可能替代子公司生產出口以避免貿易生產成本。這通常被稱為關稅跳躍投資。也許是因為這個理論相當簡單而且尋常，一般情況下很少有研究專門檢驗這一假設。另一個可能的原因是數據驅動。在各行業間一致的非關稅保護形式很難進行量化。許多企業層面的研究采用產業級別的措施來控制各種貿易保護方案，但往往結果好壞參半，其中包括Grubert和Mutti（1991），科格特和張（1996），和Blonigen（1997）。一種替代產業階層措施是通過反傾銷給企業提供特定的相當大的反傾銷稅來實現的。公司面臨著要使用更加精確的措施來應對法律保護，Belderbos（1997）和Blonigen（2002）均發現關稅跳躍FDI更有力的證據，盡管Blonigen的分析結果強烈暗示出這種反應只有總部設在發達國家的跨國公司才能看到。這可能是關稅跳躍貿易保護與其他措施混合的另一個原因，外商直接投資需要大量的費用，很多小出口企業可能無法融資或尋找有利可圖的方面。事實上，貿易保護可以明確地針對FDI較少的進口來源地。這表明外國直接投資和貿易保護可能是內源性的，關于這一問題幾乎沒有被實證過。有一個例外是Blonigen和FIGLIO（1998年），他們發現的證據表明，增加外國直接投資進入美國參議員的州或美國眾議院的地區，會增加他們把票投給進一步的貿易保護的可能性。3.5 貿易效應

先前討論到這一點的局部均衡研究在很大程度上忽略了外商直接投資的貿易影響，而這與潛在的FDI 的變化拉動力有著密切的聯系。可能最常引用FDI的動機是作為出口到東道國家的替代品。由于巴克利和卡森（1981）的模型所呈現出的，可以認為出口是固定成本較低，但運輸和貿易壁壘可變成本較高。與子公司服務于同一市場引入FDI允許大幅降低這些可變成本，但可能涉及更高的大于出口成本的固定成本。這表明了一個自然發展規律，一旦國外市場對跨國公司的產品需求達到足夠大的規模，那么將會從出口發展到FDI。

在早期的論文中利普西和Weiss（1981;1984）對美國對東道國的FDI 以及出口進行回歸分析，發現了一個正相關性，這違背了FDI替代出口的原理。然而，這些論文忽略了東道國市場這個變量的內生性，這一變量可以將跨國公司引進FDI以及出口產品的意愿朝著相同的方向增加或者減少。Grubert和Mutti（1991）根據出口銷售，使用了利普西和Weiss（1981）類似的數據得到了負相關的回歸結果，盡管結果在統計學上是不顯著的。

Blonigen（2001）認為，問題在于貿易流量，要么是用最終產品替代了跨國公司的分支機構在同一國家生產產品，要么是將生產最終產品所使用的中間產品作為流量統計。前一種情況導致“貿易”和“外國直接投資”之間的負相關關系，而后者顯示兩者之間的正相關關系。Blonigen使用日本出口美國的10位制的關稅協調制度下產品級別的貿易和FDI數據，結果顯示日本對美國的FDI增加引起日本生產這些產品的中間產品的出口也增加了，但是最終產品的出口卻下降了。赫德和里斯（2001）和斯文森（2004）分別使用日本企業層面的數據以及美國行業層面的數據提出了類似的證據。

上述討論中一個潛在的問題是企業之間的關系（如投入到分銷商的供應商），有可能影響FDI決策。日本企業往往在供應商和分銷商間有更正式和公開的連接，所謂縱向聯系財閥。赫德，里斯和斯文森（1995）探討了是否其他日本企業在美國的一個州或鄰近州的選址會通過企業相似的縱向聯系財閥影響隨后日本跨國公司的FDI。他們發現確實是這樣，特別對于汽車部門來說，并且把這個作為有正式的供應商-經銷商關系的企業之間產生了聚集經濟的證據。

其他研究考慮了橫向聯系財閥對日本FDI的影響。橫向聯系財閥是在許多行業間企業集團的分組，但中心是圍繞日本大型銀行。這樣的活動對FDI的三大潛在影響已經被提出。主要的潛在影響是利用橫向聯系財閥的銀行作為低成本集資的來源，這將增加公司的整體投資，包括對外投資。正如霍什、卡什亞普和Scharfstein（1991）提到的，有一個財閥銀行成員這樣的關系可以降低監督成本，降低資金成本。他們對日本制造業企業進行分析發現的證據表明，比起其他企業這些橫向聯系財閥的公司在投資活動中比較少受限。隨后的研究中檢測了是否橫向聯系財閥增加了日本企業的對外直接投資，但往往結果很不顯著或敏感（例如，見Belderbos和Sleugwaegen，1996）。

Blonigen，埃利斯和福斯滕（2005年）注意到了橫向聯系財閥的另一個可能的影響俄林模型的精確檢驗公式的形成遭遇了巨大的障礙，當有多于兩個國家和地區的兩個以上的生產要素時該模型預測貿易流量則可能有較大的不確定性。

第二篇：英文翻譯

Introduction: with the rapid development of the economy, China ‘smprehensive national power has been improved effectively.As a saying said;“Want to become rich first road”.So China has begun to build the high-speed rail since years ago.The building of the high~speed rail is suited to China's national conditions and help our country to run well in the strong competition of the world.大多數經濟學家認為：交通基礎設施的供應水平和能力必須適度超前，否則就會影響社會經濟持續、穩定 和健康發展。這就意味著要加大對交通基礎設施的投資，但是政府在加大交通基礎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。從中國目前的經濟發展和人民的收入狀況來說，我認為中國高 鐵弊大于利.Most economists believe that: the supply and capability of transportation infrastructure must advance appropriately, otherwise it will affect the sustainable, stable and healthy development of social economy.This means that we have to increase the investment into transportation infrastructure,But while government increase the investment into transportation infrastructure, it will to some extent decrease the practical measures to improve people's livelihood.From China's current situation, I think it will do more harm than good to build high-speed railway in China.Piont1: Building too fast go against the laws of economic development, causing many problems, such as loan repayment, staff placement.And high-speed railway construction needs large investment, from the use of the actual situation, the possibility of short-term cost recovery do not, there is also the problem of capital wasting.建設速度過快，容易違背經濟發展規律,同時面對的問題較多，例如貸款償還，員工安置等。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。武廣高鐵總投資約 1166 億元，目前的線路至少能開 120 對車，但實際上只開了 33 對，而且還坐不滿，這是資本的嚴重浪費。所 以說高鐵建設不僅需要大筆的投資，而且從運用的實際的情況來看，短期收回成本的可能性根本就沒有。The fast building speed will violate the rule of economic development, and at same time it faced many problems, such as loan repayment, staff placement.First high-speed railway of China-from Beijing to Tianjin, it was launched in August 2008, after one year it lossed 70 millions.The total investment of

Wuhan-Guangzhou high-speed rail was about 110 billions yuan, now it is able to drive at least 120 pairs of cars, but in fact only 33 to drive, and lots of seats are empty, this is a serious waste of capital.The high-speed railway not only requires large construction investment, but also, it is impossible to recovery the short-term cost based on its actural implement.Poiimnt2: The building of the high spee

d rail can drive the development of the industry related.for example, the building need many workers and the new technology, so it expand the employment and promiot the technological innovation.In another word through the building, more steel products are needed.Another important hand is transport during the Spring Festival.During this period of time, large numbers of people going home together.So the high speed rail can relieve the transportation pressure ectively 高鐵的票價較高，例如京津高鐵，它行駛 30 分鐘，卻要 69 元票價，讓人望而生嘆啊。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。武廣高鐵開通后，原有 的一些客運列車停運，意味著中低收入者將被迫選擇高鐵，接受高票價。這種行為傷及了底層人民的最根 本利 e 而且建設過程中容易出現貪污腐敗問題。The fare of high Speed Rail is higher, for example, the Beijing-Tianjin high-speed rail, it costs 69 yuan for only drive 30minuts.China's GDP ranks the second in the world, but per capita GDP still ranks out of hundreds in the world, the poor is the majority.When Wuhan-Guangzhou high-speed railway was used, the original passenger trains were stopped, which means low-incomer will be forced to choose high-speed rail and accept the high fares.This action has

impair interests of the low class people, and the corruption problem will be prone to easily during the process of building.新建高鐵實際是在現有幾種交通方式的基礎上新增一種交通方式。建成之后會與高速公路、現有鐵路、飛 機、船運形成競爭關系，在原有運力并不緊張的背景下必然形成運力過剩。新建的高鐵主要是客運專線，因此高鐵并不會加快貨物與資金的周轉速度，不會降低全社會運行成本。要修建如此龐大的高速鐵路網，必將消耗大量的資金，必將擠占人們收入上漲的空間與企業利潤空間（加重稅負）如果將此財政投入醫療、。社保、教育、技術研究，則會消除人們存錢的預防養老動機從而擴大消費，利于中國經濟可持續發展。綜 上所述，在中國大規模修建高鐵對中國經濟的長遠發展來講是弊大于利，不利于擴大內需、不利于產業結 構調整 結論：The high-speed railway will compete with the existing highway, railway, aircraft, shipping after it consummation which will lead to a situation capacity.The new high-speed railway is mainly to carry passenger, so it will not speed up the turnover rate between cargos and the capital and will not decrease the costs of the whole social transportation.To build such a large network of high-speed rail will need a large amount of money, the government must increase the taxes of people and enterprise to raise the capital.If this financial investment used in health care, social security, education, tec

第三篇：英文翻譯

Overview of the Global System for Mobile Communications 1 History of GSM During the early 1980s, analog cellular telephone systems were experiencing rapid growth in Europe, particularly in Scandinavia and the United Kingdom, but also in France and Germany.Each country developed its own system, which was incompatible with everyone else’s in equipment and operation.This was an

undesirable situation, because not only was the mobile equipment limited to operation within national boundaries, which in a unified Europe were increasingly unimportant, but there was also a very limited market for each type of equipment, so economies of scale and the subsequent savings could not be realized.The Europeans realized this early on, and in 1982 the Conference of European s Posts and Telegraphs(CEPT)formed a study group called the Group Special Mobile(GSM)to study and develop a pan-European public land mobile system.The proposed system has to meet certain criteria: ·Good subjective speech quality ·Low terminal and service cost ·Support for international roaming ·Ability to support handheld terminals ·Support for range of new services and facilities ·Spectral efficiency ·ISDN compatibility In 1989, GSM responsibility was transferred to the European Telecommunication Standards Institute(ETSI), and phase I of the GSM specifications were published in 1990.Commercial service was started in mid-1991, and by 1993 there were 36 GSM networks in 22 countries.Although standardized in Europe, GSM is not only a European standard.Over 200 GSM networks are operational in 110 countries around the world.In the beginning of 1994, there were 1.3 million subscribers worldwide, which had grown to more than 55 million by October 1997.With 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 communications.The developers of GSM chose an unproven(at the time)digital system, as opposed to the then-standard analog cellular systems like AMPS in the United States and TACS in the United Kingdom.They had faith that advancements in compression 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 cost.The over 8,000 pages of GSM recommendations try to allow flexibility and competitive innovation among suppliers, but provide enough standardization to guarantee proper interworking between the components of the system.This done by providing functional and interface descriptions for each of the functional entities defined in the system.2 General Concepts 2.1 Analog Versus Digital Telephony Systems First-generation systems were analog.During the early 1980s these underwent rapid development in Europe.Although 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 compatibility among them.Compared with these systems, the main advantages offered by GSM, which is the most important of the second-generation digital systems, are: ·Standardization;·Capacity;·Quality;·Security.Standardization guarantees compatibility among systems of different countries, allowing subscribers to use their own terminals in those countries that have adopted the digital standard.The lack of standardization in the first-generation system limited service to within the borders of a country.Mobility is improved, since roaming is no longer limited to areas covered by a certain system.Calls can be charged and handled using the same personal number even when the subscriber moves from one country to another.Standardization also allows the operator to buy entities of the network from different vendors, since the functional elements of the network and the interfaces between these elements are standardized.This means that a mobile phone from any manufacturer is able to communicate with any network, even if this network is built with entities from different vendors.This leads to a large economy of scale and results in cost reduction for both the operator and the subscriber.Furthermore, the phone cost is also reduced, because GSM is an international standard, produced quantities are greater and the level of competition is high.With respect to capacity, the use of the radio resource is much more efficient in a digital system such as GSM than in an analog system.This means that more users can be allocated in the same frequency bandwidth.This is possible with the use of advanced digital techniques, such as voice compression algorithms, channel coding, and multiple access techniques.Note that capacity gains are also achieved with radio frequency reuse, which had also used in analog systems.Frequency reuse means that a given carrier can be employed in different areas.The quality in digital transmission systems is better, thanks to the channel coding schemes that increase the robustness in the face of noise and disturbances such as interference caused by other users or other systems.The quality improvement is also due to the improved control of the radio link, and adaptations to propagation conditions, with advanced techniques such as power control or frequency hopping.This will be explained in greater detail in the next section.In terms of security, powerful authentication and encryption techniques for voice and data communications are enabled with GSM, which guarantees protected access to the network, and confidentiality.2.2 Cellular Telephony In mobile radio systems, one of the most important factors is the frequency spectrum.In order to make the best use of the bandwidth, the system is designed by means of the division of the service area into neighboring zones, or cells, which in theory have a hexagonal shape.Each cell has a Base Transceiver Station(BTS), which to avoid interference operates on a set of radio channels different from those of the adjacent cells.This division allows for the use of the same frequencies in nonadjacent cells.A group of cells that as a whole use the entire radio spectrum available to the operator is referred to as a cluster.The shape of a cell is irregular, depending on the availability of a spot for the BTS, the geography of the terrain, the propagation of the radio signal in the presence of obstacles, and so on.In dense urban areas, for instance, where the mobile telephony traffic is important, the diameter of the cells is often reduced in order to increase capacity.This is allowed since the same frequency channels are used in a smaller area.On the other hand, reducing the cell diameter leads to a decrease in the distance necessary to reuse the frequencies(that is, the distance between two co-channel cells), increasing co-channel interference.In order to minimize the level of interference, several techniques are used on the radio interface.A basic example of cluster organization is shown in Figure 1.In this example, we see a reuse attern for seven different frequencies, f1 to f7.These frequencies correspond to the beacon carrier of each cell, on which signaling information about the cell is broadcast(see Section 2.7).It can be seen from this figure that a given carrier can be reused in two separate geographical areas, as long as these areas are far enough from each other to reduce the effect of interference.With this technique of dividing the area in cells and clusters, the operator can increase the area it is able to cover with a limited frequency bandwidth.Figure 1 Example of a Cell Planning

在80 年代初期期間，模式手機系統在歐洲體驗迅速增長，特別在斯堪的那

維亞和英國，以及法國和德國。每個國家開發了它自己的系統，在設備和操作 上是互不相容的。這是一個不受歡迎的情況，因為不僅移動通信設備被限制在國 界之內，這在統一的歐洲是越來越不重要的，而且每種類型的設備都只有一個非 常有限的市場，因此經濟尺度及隨后的儲蓄不可能體會。

歐洲人早就意識到了這點，并且在1982 年歐洲郵電管理聯合會(CEPT)上形 成了移動通信特別研究組(GSM)來研發一個能在全歐洲大陸通用的移動通信系 統。提出的系統必須符合以下標準： 〃通話質量好

〃終端及服務費用低 〃支持國際漫游

〃能夠支持可隨身攜帶的終端 〃支持一系列新的服務和設備 〃效率高

〃與ISDN 兼容

1989 年，GSM 的責任轉移了到歐洲電信標準學院(ETSI)，并且GSM 規格的

第一階段也在1990 年出版了。商業服務在1991 年中期開始了，截至1993 年有 36 個GSM 網絡在22 個國家誕生了。GSM 不僅僅是歐洲標準，盡管它是在歐洲 規范化的。現已有200 多個GSM 網絡在全球110 個國家和地區運行。1994 年初 期全球有1,300,000 用戶，截至1997 年10 月已突破55,000,000 用戶。隨著美國

后來在GSM 領域制造了一個詞條PCS1900 作為GSM 的拓展,GSM 系統已發展至 各大洲,并且縮寫詞GSM 現在已可以代表移動通信的全局系統。

GSM 開發商選擇了一個當時未經證明的數字系統，與后來的標準模式蜂窩系 統相對，就象美國叫AMPS，而英國叫TACS 一樣。他們堅信能夠推進壓縮算法 和數字信號處理器使其能夠根據質量和費用將原始標準和系統連續改善。GSM 推薦8,000 頁設法使得在與供應商競爭之中體現靈活性和創新，但提供 足夠的標準來保證在系統的組分之間適當配合工作。完成提供功能和接口描述的 功能個體在系統中都有定義。

第一代系統是模擬的。上個世紀80 年代初期在歐洲迅速發展。雖然所有北 歐國家使用TACS 系統，英國和意大利使用NMT 系統，它們之間還有各式各樣 的系統不兼容。和這些系統相比，GSM 提供的更重要的第二代數字系統主要優勢 體現在： 〃標準化； 〃容量； 〃質量； 〃安全。

標準化保證了不同國家系統之間的兼容性，允許采取了數字化標準的國家的 訂戶使用他們自己的終端。在第一代系統中缺乏標準化的有限服務為在國家的邊 界之內。流動性被改進，漫游不再被限制到某一系統包括的面積之內。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。因為網絡的功能元件和這些元素之間的接口被規范化，操作員可以從不同的 供營商購買。這意味著所有制造商的移動電話能與任何網絡溝通，即使這個網絡 是由不同的供營商的功能元件建立的。這為操作員和訂戶帶來費用成本的降低。此外，電話費用也降低了，因為GSM 是國際標準，生產數量大，競爭水平高。能力方面，數字系統如GSM 比模擬系統使用的無線資源更有效。這意味著 更多的用戶可以使用同一頻帶。這就有可能利用先進的數字技術，如語音壓縮算 法，信道編碼和多址接入技術。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。頻率復用意味著同一載波可以在不同的地區重復使用。由于這種信道編碼方案，提高了可靠性及對噪音和其他用戶或系統的干擾能 力，數字傳輸系統的質量更好了。質量改進的原因還在于改善了對無線連接的控 制，并適應傳播條件下，使用先進的技術，如電源控制或跳頻。質量改進的原因 還在于使用先進的技術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。這些將在下文中做更詳盡的解釋。

在安全方面，GSM 具有語音和數據通信的強大的認證和加密技術的功能，保 證了保護接入網絡和保密性。

在移動通信系統中，一個最重要的因素就是頻譜。為了最有效地利用帶寬，系統設計的目的是通過基站的服務區到周邊小區，理論上是一個正六邊形。每個 小區有一個收發基站（BTS），其中，以避免相鄰小區的不同無線信道在運行時 產生相互干擾。這樣可以在不相鄰的小區使用同一載頻。一組小區，作為一個整 體，給運營商提供整個無線電頻譜是指一個區群。小區的形狀是不規則的，這取 決于是否有現成的基站，地理地形，無線電信號傳播中存在的障礙，等等。例如，在人口密集的城市地區，移動電話的通行非常重要，小區的直徑往往 會減小，以提高其通行能力。

這是允許的，因為同一頻道只在一個較小的地區內使用。另一方面，小區直 徑的減小導致使用同一頻率的小區間的距離（即兩個公共通道小區間的距離）縮 小了，增強了各頻道之間的相互干擾。為了盡量提高抗干擾的能力，無線接口使 用了一系列技術。

一個基本的區群組織的結構如圖1 所示。在這個例子中，我們看到了一個復 用模式的7 個不同的頻率，f1 至f7。這些頻率對應于每個小區的信標載波，整個

小區的信號信息就靠它們被傳播出去（見第2.7 節）。從圖中可以看出，某一載 波可在兩個不同的地理區域重復使用，只要這兩個地區離的足夠遠，相互之間的 干擾足夠小。這一技術把地區分成小區和區群，經營者可以利用有限的帶寬增加 覆蓋區域的面積。

第四篇：英文翻譯

School Profile

Jin Yuan Primary School was founded in 1966，and now it has 40 years? history.Thepredecessor of the school is ShiMian kuang Children Shool.In May 1993 ,It was placed under the Dalian Development Zone.In 2002, the new building was reconstruction in the school site.Now it occupies a total area of 18500 square meters, with a total construction area of 9020 square meters, it has got 30 class and 1478 students.Our school always adhere to the school mission-“To lay the foundation for the development of student life” and school

philosophy “To train the younger generation for adapting to the new society”.with “implementing quality education, making our school into modernization, distinctive characteristics, high-grade The 'people satisfaction' schools ”for the school mission and goals.Focusing on behavior, raising habits, pursuingdevelopment, hing research,benefit, the high quality;grasping

characteristics, treeing famous“ as the school ideas.”Innovation in operating a school, Distinctive Features,“ as the school way.Our school has been named the standardization of school facilities,education and management of Dalian advanced group, Green School of Dalian , big break in Dalianadvanced unit for physical education curriculum standard education health system,development zone course reform summary advanced unit, the characteristics of the development of school-based curriculum development awards such as prizes, Excellence Award and many other honors.In addition, teaching and research training center was also named the Development of information technology, sports, music, experimental point of school mental health disciplines.School emphasis on ”Science Education“, it has been named the Science and technology activities advanced units;land-sea model training base in Liaoning Province;Dalian Science and Technology Advanced Unit;advanced science and technology activities in Dalian youth units;The intelligent robot teaching activities carried out to further broaden the field of science teaching in recent years, we got soccer robot competition and the Youth Science and Technology Invention Contest winners many times in national, provincial and municipal.Our school was known by scientific and technological innovations, it has become a golden source of education and school characteristics of primary brand, and its fruitful results of educating people to win recognition of the higher education sector and social praise.Our school actively promoting international exchanges and cooperation.Based on the national culture, the students involved in multicultural perspective, let the student to have the ability to

communicate with different culture and cultural understanding

ability, feeling the other civilizations, inheriting Chinese culture, and for students build facing the world, developing yourself and

development of China's platform.At present,we have established the friendly and cooperative relations with Singapore, Britain and other countries of the schools.Our school is committed to the construction of educational information, establishing the educational information to promote the development strategy of modernization of school education.We was honored with the first model school education information by Dalian Municipal Bureau of Education.Physical education in our schoolis also flourished, we always adhere to the ”Sunshine Sports“ project.To ensure that every student at least one hour of exercise a day, each have a favorite sport, the school was named the physical education curriculum standards of Dalian advanced unit, DalianBig calisthenics demonstration school, Dalian”campus football

project“ Development of school.In recent years,school ?s sports teams in all kinds of various game had good performance , and it becomes the school?sbeautifulcard.Standing at a new starting point, facing the new century, we will try to”build multicultural education, reveal personality, improve

the educational grade, promote the connotation development" as our target, makes determined efforts, scientific planning, and strive to improve the level and constantly expand its reputation, trying to be the children paradise of JinYuan Primary School.

第五篇：英文翻譯

whether the university student should pay more atteion on studying or not ?the answer issure.First of all,during these time,we can touch more things,whichwehave not ever meet before and make a graetinflunce on our future life,If we don't handle it well,maybe we will lose a lot of thingswe adapt to sociaty more easily and more diffcult.we have time to play, but when you are playing and relaxing, dont forget the things you must do at school.school life is on of the best sections of your life.you need school life and time to learn and do things.