Методическая разработка для студентов, обучающихся по направлению 120100 «Геодезия и дистанционное зондирование»
XIII. Перескажите текст, опираясь на вопросы, приведенные в
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- XV. Составьте собственные диалоги, используя данные слова и фразы.
| XIII. Перескажите текст, опираясь на вопросы, приведенные в
упражнении XII. XIV. Научимся разговаривать по телефону. Выучите следующий диалог: I. Good morning. My name is Ivan. Can I speak to Mary? M. Hello, Ivan. Mary speaking. Can I help you, Ivan? I. Mary, can you give me Lena`s number? M. Just a moment (минуточку). It` s 2438957. I. Thank you so much, Mary. I`m very much obliged to you. M. You are always welcome, Ivan. Thank you for calling. Goodbye for now. XV. Составьте собственные диалоги, используя данные слова и фразы. Can you come to…? Can you lend me … It`s good to hear from you (приятно слышать Вас); she/he isn`t in; Can you ask her/him to ring me?; I`ll ring back later (перезвоню позднее); Can I take a message? XVI. Прочитайте и переведите следующий текст со словарем: Datum In surveying and geodesy, a datum is a reference point or surface against which position measurements are made, and an associated model of the shape of the earth for computing positions. Horizontal datum is used for describing a point on the earth's surface in latitude and longitude or another coordinate system. Vertical datum is used to measure elevations or underwater depths. Horizontal datum The horizontal datum is the model used to measure positions on the earth. A specific point on the earth can have substantially different coordinates, depending on the datum used to make the measurement. There are hundreds of locally-developed horizontal datums around the world, usually referenced to some convenient local reference point. Contemporary datums, based on increasingly accurate measurements of the shape of the earth, are intended to cover larger areas. The WGS 84 datum, which is almost identical to the NAD83 datum used in North America, is a common standard datum. 29 Vertical datum A vertical datum is used for measuring the elevations of points on the earth's surface. Vertical data are either tidal, based on sea levels, gravimetric, based on a geoid, or geodetic, based on the same ellipsoid models of the earth used for computing horizontal datums. In common usage, elevations are often cited in height above sea level; this is a widely used tidal datum. Because ocean tides cause water levels to change constantly, the sea level is generally taken to be some average of the tide heights. Mean lower low water — the average of the lowest points the tide reached on each day during a measuring period of several years — is the datum used for measuring water depths on some nautical charts, for example; this is called the chart datum. Whilst the use of sea- level as a datum is useful for geologically recent topographic features, sea level has not stayed constant throughout geological time, so is less useful when measuring very long-term processes. [Источник: Wikipedia, URL: https://en.wikipedia.org/wiki/Geodetic_datum (время обращения - 17.06.15)]. жүктеу/скачать 0.86 Mb. Достарыңызбен бөлісу:
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