It is now almost two years since the European Union decided to go ahead with pla

游客2024-03-04  16

问题 It is now almost two years since the European Union decided to go ahead with plans to launch a satellite-navigation network to rival America’s existing Global Positioning System (GPS). For much of this time, Galileo, the European system, met with strong opposition from America. However, a round of talks last November seems to have ease American concerns. The final details remained to be negotiated in talks, but the outlook for an agreement was good.
The core of the disagreement between the EU and America was whether the signals from the two competing systems might interfere with one another. More specifically, the Americans wanted the ability to jam Galileo without rendering GPS signals ineffective. The agreement reached in November was the first step in this direction. In return for the modification of Galileo’s signals, the Americans agreed to give Europe technical assistance in developing Galileo, and to make sure that the third generation of GPS, to be carried out in 2012, will conform to Galileo’s standards. This will aid the interoperability (互用性)of the two systems, which is a commercial goal of both sides. It will also, in principle, give the Europeans the ability to jam the American signals in the event of a crisis in which the two sides’ interests differ.
There is a bewildering array Of different sorts of signals involved in each network. GPS currently has two, a civilian channel known as C/A and a military one, Y-channel. Plans for an additional military channel, called M-code, are in the works. Galileo will debut (初次公开) with five different signals: one freely available to all; a commercial service which is more precise; a "safety-of-life" service that can be used for critical applications; a "public regulated service" (PRS) which will be used by the EU’s governments; and a fifth service that combines positioning information with a distress beacon, which could be used by ships at sea. The negotiations in November resolved a conflict between America’s M-code and the European PRS. What remains is to harmonize Galileo’s free signal with the M-code.
Both systems rely on signals precisely timed from atomic clocks carried by the satellites. A user looks at the time on at least four satellites, and triangulates (作三角测量)between them to find his position. Differences in the details of the different signals are what make the fees of applications. Some are more precise than others, and they also have different levels of encryption, to prevent unauthorized users from accessing them.

选项 A、EU and US are always having disagreements on almost everything.
B、US becomes an enemy of EU because of their satellite network.
C、The talks between EU and US have resulted in complete agreement.
D、Even though disagreement still exists, agreement can be expected.

答案 D

解析 由题干中的the first paragraph定位到原文首段。[精析] 原文首段最后一句but the outlook for an agreement was good(但是达成一致的前景乐观)用强转折词but强调协议的前景乐观,也即达成协议有望之意。故D)“虽然分歧依然存在,但达成一致仍可期待”正确。[排除干扰] A)“欧盟和美国总是几乎在所有事情上存在分歧”观点扩大化,原文只提及在卫星方面的分歧;原文只是提及两者to rival(竞争),并未提及两者成为enemy,故排除B);由原文The final details remained to be negotiated in talks(最终细节还有待讨论)可推知C)“欧盟和美国之间的谈判已经达成了完全一致”错误,也排除。
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