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Архитектура Аудит Военная наука Иностранные языки Медицина Металлургия Метрология Образование Политология Производство Психология Стандартизация Технологии |
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Архитектура Аудит Военная наука Иностранные языки Медицина Металлургия Метрология Образование Политология Производство Психология Стандартизация Технологии |
UNIT 3 – GEOGRAPHIC INFORMATION SYSTEM (GIS)
1. GIS “Geographic Information System”. A GIS is an information system which handles geographic information. GIS is more than just a special kind of information system. It is a technology. A technology is “the whole body of1 methods and materials (документация, средства) used to achieve the stated objectives”. GIS technology is often confused with other sciences and technologies that deal with spatial data handling. These include: remote sensing, cartography surveying, geodesy, photogrammetry, and of course, the “father” science to GIS, geography. 2. A GIS is an organized collection of2 computer hardware, software, geographic data, and personnel designed to efficiently capture, store, update, manipulate, analyse, and display all forms of geographically referenced information3. It (GIS) is a computer system manipulating geographic data. Geographical data describes objects from the real world in terms of: – the object’s position with respect to a known coordinate system; – the object’s physical attributes associated with the geographical position; – the spatial relationship of the object with surrounding geographical features4 (topology). 3. Spatial Information Theory. Spatial information is always related to geographic space, i.e., large-scale space5. This is the space beyond the human body, space represents the surrounding geographic world (географ. пространство). Within such space, we constantly move around, we navigate in it, we conceptualise it in different ways. Geographic space is also the space of topographic and cadastral features (зд. характеристик объектов). Geographic space is distinct from small-scale space, or “table-top” space6. Geographic information technology is used to manipulate (выбор и анализ) objects in geographic space and to acquire knowledge from spatial facts (данные). 4. Geographical information is a unity of spatial and attribute (non-spatial) information describing an entity, e.g., the coordinates of the centre of the gravity, the identifier (ID), the address and the building year of a house. Spatial information contain coordinates, coordinate system, spatial accuracy, and geometric and topological information of an entity. Attribute information contain identifying, linking, timing and describing information of an entity, e.g. the ID, the address, the building year and colour of a building. An entity is a thing in the real world with an independent existence. The distinction between spatial and attribute information is largely arbitrary; both spatial and attribute information describe dimensions of an entity7. 5. So, just what is a GIS? GIS is a powerful set of tools8 for collecting, storing, retrieving at will, transforming, and displaying spatial data from the real world. Spatial data are data which represent objects that have physical dimensions – they take up space. Geographic spatial data occur on, in, or above the planet Earth. In the context of GIS technology, spatial data are landscape features which can be represented on a map. Spatial data occur in three forms: points, lines, and polygons or areas. In two-dimensional space, there exist no other alternatives. A soil type or forest stand appears on the land as a polygon. Rivers and roads are lines (or very narrow polygons), and wells, stream intersections, or eagle nests are points. All features of the landscape can be reduced to9 one of these three spatial data categories. This is an important concept because GIS technology is a computer technology. To use computers for handling spatial data, we must reduce our data to the computer’s level of comprehension10. We must specify three things for the computer. (1) Where each feature is in geographic space, (2) What each feature is, and (3) What is each feature’s spatial relationship to other features on the map. 6. The history of GISs started from “computer-mapping” programs in the early 1960s. The Harvard Graphic Laboratory was one of the most effective research groups developing computer-based map analysis programs. The fundamental components of a GIS and its environment (GIS-environment) are: 1. Input (a data input subsystem which collects and/or processes spatial data derived from existing maps, remote sensors, etc.). 2. Data storage and retrieval (a data storage and retrieval subsystem which organizes the spatial data in a form which permits it to be quickly retrieved, as well as permitting rapid and accurate updates and corrections11). 3. Manipulation (a data manipulation and analysis subsystem which performs a variety of tasks). 4. Output (an output which is capable of displaying all or part of the original database).
7. One more important thing we must tell the computer is what various spatial features are. The labels we attach are called attributes, and landscape features can have an unlimited variety. For example, a lake may be described by its name, depth, water quality, fish populations, chemical composition, color, bottom contour, algal levels, salinity, taste, biological productivity, ownership, etc. As new information is required, it must be added to the GIS database. Furthermore, as we use the GIS we may transform data already in the database to produce new information internally12. For example, fish population sizes, productivity levels, access, and other factors might be combined to set catch limits of fish species, which in turn become new attributes describing the lake. 8. The power of GIS is most apparent when the quantity of data involved is too large to be handled manually. The ability to perform complex spatial analysis rapidly provides a quantitative as well as qualitative advantage. The GIS offers a practical means to manage large and diverse spatial data base and provides effective tools to understand the relationships among diverse phenomena. The GIS has not only made the production and analysis of geographic information more efficient it is changing the way geographic information is perceived and used13. It is a technology that makes geographic data more malleable. 9. Despite the analytical power of this technology, a GIS, like any other system, does not and cannot exist on its own14. To be successful it must exist within a suitable organizational framework15. There must be an organization of people, facilities and equipment responsible for implementing and maintaining the GIS. Ultimately, a GIS is used to produce information that is needed by a user. The client may be a person or a group of people. To be useful to the client, information must be of the right kind and quality, presented in an appropriate format to the client to use and to be available at the right time. The GIS is operated by staff who report to a management16. That management is given the mandate to operate the GIS facilities17 in such a manner as to serve some user community within an industry, business, or government organization. 10. The data used in a GIS represent something about the real world at some point in time18. The most important aspects of data quality are: accuracy, precision, time, currency and completeness. The information in a GIS is represented in two basic forms: as maps and as tables. What distinguishes a GIS from other systems is the ability to integrate georeferenced data19. GISs are a powerful resource that provide flexible methods for exploring relationships among geographic data and assisting experts from diverse fields in pooling knowledge to solve complex problems, and to assist the users in accomplishing the goals of their respective organizations.
Notes:
Exercises Ex.1. Pronounce correctly: achieve, achievement, accurate, accurately, accuracy, arbitrary; process, processing, processed; concept, conceptual; quantity, quality, qualify, qualified, qualification; use, user, uses, used, using, useful, useless; exist, existing, existence; equip, equipped, equipment; object, objective, objectives; space, spatial, non-spatial; analyse, analyser, analysing, analysis [s], analyses, analyst; special, spatial; specify, specified, specifying, specification; geodesy, geodetic, geography, geographically; hardware, software
Ex.2. While translating pay attention to the nouns in the function of an attribute: data handling; data quality; data category; a data input subsystem; data storage and retrieval subsystem; computer system; coordinate system; large-scale space; small-scale space; “table-top” space; landscape features; soil type; stream intersections; eagle nets; computer-based map analysis program; analysis subsystem; fish population sizes; bottom contour; productivity level; spatial data base; user community; business or government organization Ex.3. Form pairs of synonyms: a) objective, different, effective, means, personnel, assist, perform, industry, quantity, include, handle, method, data, deal with, explore, accuracy, software, basic, to use, object, to acquire, to change, feature, rapid b) be concerned with, efficient, process, goal, contain, program, entity, staff, information, quick, to get, dimensions, precision, to transform, peculiarity, implement, various, facilities, to make use of, fundamental, business, investigate (study), help, technique
Ex.4. Complete the sentences: 1. GIS technology is the “whole body” of… 2. GIS is a computer system… 3. Geographic space is the space… 4. Geographic information technology is used to… 5. Geographic information is a unity of… 6. GIS is a powerful set of tools (resource) for… 7. Spatial data are data which… 8. To use computers for handling spatial data, we… 9. The fundamental components of a GIS and its environmental are… 10. As new information is required, it… 11. The power of GIS is most apparent when… 12. The GIS offers a practical means to manage… 13. To be successful GIS must exist within… 14. To be useful to the client, information must be of… 15. The most important aspects of data quality are: … 16. GISs are a powerful resource that provide… Ex.5. Translate the following sentences into Russian: 1. GISs is one of the most powerful systems for the effective use of geographic information. 2. This research team is one of the most effective groups developing computer-based maps analysis programs. 3. The ability to perform complex spatial analysis in a period of time is very important nowadays. 4. A GIS makes the production and analysis of geographic data more efficient. 5. A GIS cannot exist on its own (doesn't operate in a vacuum). 6. The information must be presented in an appropriate format to the client to use and to be available at the right time. 7. The most important aspects of data quality are: accuracy, precision, time, currency and completeness. 8. GISs are a powerful resource that provide flexible methods for exploring relationships among geographic data and assisting experts from diverse fields, in pooling knowledge to solve complex problems. 9. The ability to integrate georeferenced data distinguishes a GIS from other systems. 10. Sciences and technologies that deal with spatial data handling.
Ex.6. Translate into English using the text: 1. Технология – это (весь) комплекс методов и средств. 2. Обработка пространственных данных. 3. Все типы (виды) геопространственной информации. 4. Геопространственная связь объекта с особенностями (элементами) местности. 5. ГИС технологии используются для выбора и анализа (to manipulate) объекта в геопространстве. 6. ГИС – это технология, которая делает данные более гибкими (в зависимости от их назначения). 7. Как пространственная, так и атрибутивная информация, описывают характеристики объекта. 8. Реальная действительность (объект) – это то, что существует в реальном мире независимо. 9. Получать информацию из пространственных данных. 10. Привести данные в соответствующую компьютерную программу. 11. Группа, разрабатывающая программы анализа цифровых карт. 12. Быстрая и точная обновленная редакция и корректирование. 13. Объем (массив) данных слишком большой для обработки вручную. 14. Как количественное, так и качественное преимущество. 15. Проводить (выполнять) сложный анализ геопространственных данных. 16. ГИС – эффективное средство для понимания геореляционных связей между различными явлениями. 17. ГИС должна функционировать (существовать) в рамках соответствующей организационной, интегрированной системы. 18. Должен быть штат сотрудников, помещения, оснащение, средства для функционирования и эксплуатации ГИС. 19. Информация должна быть грамотной, качественной и своевременной. 20. Основной характеристикой ГИС является способность объединения (слияния) геопространственных данных. 21. Специалисты из различных областей.
Ex.7. Answer the questions: 1. What is a GIS? 2. What is a technology? 3. What is a GIS designed for? 4. What sciences is GIS technology often confused with? 5. What is geographic space? 6. What is geographic information used for? 7. Is geographic information a unity of spatial and attribute information describing an entity (object)? 8. What do spatial and attribute information describe? 9. What are spatial data? 10. In what three forms are spatial data presented on a map? 11. What are the main three things do we have to specify for the computer? 12. What is a history of a GIS? 13. What are the fundamental components of a GIS and its environment? 14. When is the power of a GIS most apparent? 15. What is necessary for a GIS to be successful? 16. What are the most important aspects of data quality? 17. In what two basic forms is the information presented? 18. What distinguishes a GIS from other systems? 19. What are the main functions of a GIS? Ex.8. Useful English (read, translate and learn by heart): – to handle data (information); to acquire knowledge (information) – to achieve the stated objective; to deal with; with respect to… – to manipulate objects in geographic space; large-scale space; small-scale space; – the research group developing computer-based map analysis programs – the most important aspects a data manipulation and analysis subsystem performs a variety of tasks; experts from diverse fields; flexible methods – to produce new information; information needed by the user; – to solve complex problems; the ability to perform complex spatial analysis – GIS technology makes geographic data more malleable – relationships among geographic data; the relationship among diverse phenomena |
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GIS facilities