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VII. Прочитайте и переведите текст.

Methods of Data Collection in GIS/LIS

Spatial data collection is one of the fundamental steps in the creation of a Land Information System (LIS).

The objective of GIS/LIS is to store, retrieve, transform, display and analyze spatial data to solve the complex environmental and social problems facing decision-makers, planners, local and federal governments.

Spatial data collection concerning GIS/LIS may be classified into primary and secondary methods.

The primary methods of spatial data collection refer to driving data directly from the field or from photographs.

The secondary methods refer to the processes in which data are derived from existing documents, such as maps, charts, graphs, etc.

Techniques of Geodesy.

It must be said that all the primary methods of data acquisition require a frame of reference (критерий) (geodetic networks) established by using geodetic surveying techniques. These are traditional terrestrial observation (theodolite, EDM); extraterrestrial processes such as satellite Doppler, Global Positioning System (GPS), photogeodesy.

The essential role of geodesy is to provide the point from which all the calculations and analysis of spatial data may be performed.

Techniques of Surveying.

Terrestrial surveying is the traditional method of spatial data collection.

It should be noted that before the advent of photogrammetry, surveying was the sole method.

The plane table (мензула) equipped with an alidate was the primary method of photographic surveying. Conventional surveying requires skilled and experienced field personnel (опытный персонал полевиков). They can not only observe angles, distances and height differences accurately but also can check the accuracy of the work right in the field.

Introduction of the electronic theodolite or the so-called total station (опорная станция) has made conventional surveying easier and faster. Surveying is a reliable and accurate method of data collection for GIS/LIS.

However, it is not an economical method for areas larger than 25 acres (0,4 га)since the accuracy of surveying is a function of not only the equipment but also the observational procedure, atmospheric conditions, distance between points and number of occupied stations (опорные станции). Generally, photogrammetric methods are used to map large areas.

[Источник: Английский язык. Сборник общенаучных и технических текстов на английском языке: для магистрантов, студентов 1-го, 2-го курсов заоч- ного, дневного и вечернего отделений по специальностям академии [Текст]. Часть 2 / Л.М. Никулина. – Новосибирск: СГГА, 2008. – 69 с., с.41.].

VIII. Заполните пропуски словами, данными под чертой.

1. Spatial … collection is one of the … steps for GIS/LIS.

2. Such data collection may be … into primary and secondary methods.

3. Terrestrial … is the traditional method of data collection.

4. The essential role of … is to find the point for all calculations.

5. Surveying is a … and … method for GIS/LIS.

6. Primary methods of data … require a frame of reference established by using geodetic surveying … .

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