Geoinformation technologies. Displaying information on an electronic map.
Geoinfo s-we;
C-we federal and municipal government;
C-we design
C-we are military
The graphic image consists of a substrate (background) and the objects themselves
The implementation problem is the difficulty of a formalized description of the subject area and its display on an electronic map.
The main class of geographic information systems (GIS) data are coordinate data containing geometric information and reflecting the spatial aspect. Basic types of coordinate data: point (nodes, vertices); line (open); contour (closed line); polygon (area, region). Relationship types:
Building complex elements from simple objects
Calculated from object coordinates
Defined using a special description and semantics of the input data
The graphics environment is based on vector and raster models. Vector - vectors require less memory.
Raster models are cellular, each cell corresponds to a color and density.
Raster models are divided into regular, irregular and nested (recursive or hierarchical) mosaics. Flat regular tilings come in three types: square, triangle, and hexagon.
Question #13
Basic information technologies: information security technologies
In connection with the introduction of IT, there was a need to protect information.
Types of information threats:
Failures and malfunction of technical facilities
Intentional threats by attackers
The main causes of failures and failures of equipment:
Aging and wear
Incorrect use of resources
Program violations
Troubleshooting:
Redundancy of computer resources
Protection against incorrect use of resources
Identification and timely elimination of errors
Building redundancy - redundancy of hardware components and machine media.
Information redundancy - periodic or permanent backup of data on the main and backup media
Functional redundancy - duplication of functions and introduction additional features in software and app resources.
Deliberate Threats:
With constant human involvement
Malware working without human intervention
Threat protection:
Prohibition of unauthorized access
Impossibility of unauthorized use of resources
Detection of the fact of unauthorized access
The main method of protection against unauthorized access:
Identification
Authentication
Definition of authority
Passwords: simple - constant, complex - dynamically changing:
Modification of simple passwords, one-time passwords
Method "request-response" password selection from the array list
Function Methods
Programs;
External memory(files, directories, logical drives);
RAM;
Time (priority) of processor usage;
I/O ports;
external devices.
There are the following types of user rights for access to resources:
Universal (full provision of the resource);
Functional or partial;
Temporary.
The most common ways to restrict access are:
Differentiation by lists (users or resources);
Using the authorization matrix (rows - identifiers columns - resources computer system);
Question #14
Basic information technologies: CASE-technologies. Objectives of the OMG consortium and the OMA specification. An ideal object-oriented CASE tool. Criteria for evaluation and selection of CASE tools.
Functionally modular approach is based on the principle of algorithmic decomposition with selection functional elements and establishing a strict order of actions to be performed. "-" unidirectional flow of information, insufficient Feedback
Object Oriented the approach is based on object decomposition with a description of the system behavior in terms of the interaction of objects.
Under CASE technology we understand the complex software tools that support software development and maintenance processes, including requirements analysis and formulation, design, code generation, testing, documentation, quality assurance, configuration management, and project management.
Because of the two approaches to software design, there are CASE technologies focused on a structural approach, an object-oriented approach, and a combination. OOP has become widespread. Reasons for this:
Assembly capability software system from prefabricated components
Possibility of accumulation of design solutions in the form of libraries
Easy to make changes to projects due to encapsulation
Rapid adaptation of applications to changing conditions
The possibility of organizing parallel work of analysts, designers and programmers.
The concepts of object-oriented approach and distributed computing became the basis for the creation of the Object Management Group (OMG) consortium. The main activity of the consortium is the development of specifications and standards for the creation of distributed object systems in heterogeneous environments. The specification called Object Management Architecture (OMA) became the basis.
OMA consists of four main components representing the specifications of the various levels of application support.
Object Request Broker Architecture (CORBA) defines how objects interact in a heterogeneous network;
Object services are the main system services used by developers to build applications;
Universal means are high-level system services focused on supporting user applications (e-mail, printing tools, etc.);
Application objects are designed to solve specific application problems.
The concept of an ideal object-oriented CASE tool.
The authors of the most common object-oriented methods are G. Booch, D. Rambo, I. Jacobson (UML).
The classical formulation of the problem of developing a software system (engineering) is a spiral cycle of iterative alternation of the stages of OO analysis, design and implementation.
Question #15
"Basic information technologies: telecommunication technologies."
architecture
Architecture comp. networks
1. peer-to-peer
2. client server
3. client-server for Web technologies
1. terminal - for display and input
MainFrame - all calculations and data
2. Local, corporate, global networks connecting client PCs using resources and servers providing resources.
The view component is an interface;
Application component - responsible for the implementation of functions;
Data access component (resource manager) - responsible for defining and managing data;
1. Access to remote data
"-" low performance
2. Data management server
"+" Part of the data is transmitted
Applied functions are unified
"-" Lack of a clear distinction between the presentation component and the application component.
3. Integrated server
"+"High performance
Centralized Administration
Resource Saving
4. Thin client
"+" Organization of different application components for different tasks, without reconfiguring the server and client.
Question #16
"Basic information technologies: artificial intelligence technologies."
The system is called intelligent if the following main functions are implemented in it:
Accumulate knowledge about the world around the system, classify and evaluate them in terms of pragmatic usefulness and consistency, initiate the processes of obtaining
new knowledge, to correlate new knowledge with previously stored;
To replenish the received knowledge with the help of a logical conclusion that reflects patterns in the world around the system or in the knowledge accumulated by it earlier, to obtain generalized knowledge based on more particular knowledge and logically plan their activities;
Communicate with a person in a language as close as possible to natural human language and receive information from channels similar to those used by a person when perceiving the world around him those knowledge that is stored in memory, and those logical means of reasoning that are inherent in the system.
Knowledge base - set of environments that store knowledge various types. Fact Base- stores specific data. Rule base are elementary expressions. Base of procedures– application programs that perform transformations and calculations. Pattern base– information related to the features of the environment in which the system operates. Metaknowledge base - self knowledge base. Goal base– scenarios to achieve the goals that came from the user or the system itself. planning block– decision planning.
Intelligent information retrieval systems - interaction with problem-oriented databases in natural language.
Expert systems - computing system using expert knowledge and inference procedures to solve problems.
Calculation and logic systems - allow solving management and design tasks according to their formulation and initial data.
hybrid systems
Knowledge representation models:
Semantic networks - graph, vertices - concepts, arcs - relationships between concepts.
Question #17
"Information Technologies of Organizational Management (Corporate Information Technologies)."
Management methods and IT:
1. Resources - DBMS
2. Processes - Workflow
3. Corporate knowledge (communications) - Intranet
1) MRP - a methodology for planning the material resources of an enterprise, used in conjunction with MPS - a methodology for volume-scheduling planning. CRP - methodology for planning production resources (capacity).
MRP2 is an integrated methodology for planning and managing all production resources of an enterprise MRP / CRP and using MPS and FRP - financial resource planning.
ERP - integrated planning of all business resources of the enterprise. For trade, services, finance.
CSRP is resource scheduling synchronized with consumption.
Because many suppliers and buyers are involved in production - a new concept of supply chains - accounting for the analysis of the entire chain of transformation of goods from raw materials to finished products. Further development of supply chains - virtual business- a distributed system of several companies and covering the full life cycle of a product or the division of one company into several virtual businesses.
3) Intranet - corporate communications. 3 levels of implementation of telecommunication technologies: hardware, software and information. It differs from the Internet only in terms of information. 3 levels of this aspect: 1. Universal language for representing corporate knowledge - does not depend on the subject area. and defines grammar and syntax. Graphical description of data models. Tasks: unification of knowledge representation, unambiguous interpretation of knowledge, division of knowledge processing processes into simple procedures. 2. View models - determine the specifics of the organization's activities. Describe primary data. 3. Factual knowledge - a specific subject area. and are primary data.
Architecture.
1. Centralized architecture on mainframes where data is stored and processed. "+" ease of administration, information protection.
2. Client - server.
Data on the server, not information
For data exchange - a closed protocol
On clients, data is interpreted and converted into information
Fragments of application systems are hosted on clients
«+» low network load, high reliability, flexible setting of the level of user rights, support for large fields.
"-" difficulty of administration (territorial disunity), insufficient degree of protection of information from unauthorized actions, closed protocol (specific to this IS).
The Intranet architecture is a combination of the previous ones. All information and processes on the central computer. At workplaces - the simplest access devices that provide the ability to manage processes in the IS.
"+" information on the server, open type protocol, application programs on the server, facilitated centralized management of the server and slave.
Question #18
"Information technologies in industry and economy"
When designing an automated control system, the issue of compatibility, standardization was often ignored, which made it difficult to implement modern technologies and led to high costs for modernization. Corporate information systems (CIS) based on the principles of corporate information technologies and modern standards have become widespread.
Formation of reporting indicators ( tax services, statistics, investors, etc.) obtained on the basis of standard accounting and statistical reporting;
Development of strategic management decisions for business development based on a base of highly aggregated indicators;
Development of tactical decisions aimed at operational management and solved on the basis of a database of private, highly detailed indicators that reflect various aspects of the local characteristics of the functioning of the structure.
The main difficulties in diagnosis:
Survey, system analysis and assessment of the existing structure and management technologies
Development of new options for organizational structures and IT-based management technologies
Development of provisions for the reorganization of management, an implementation plan, regulations for management workflow.
CIS: - replicable - does not require further development for small businesses.
Custom - unreliable, production with very high specifics
Semi-custom - flexible, large enterprises
PCS principles:
Compatibility of software and hardware of various manufacturers
Comprehensive testing and debugging of the entire system at the stand of the integrator based on the customer's specifications. Technical languages of relay-contact circuits.
The lower level of the process control system is the controllers that provide the primary processing of information. The upper level - powerful computers that perform the functions of database servers and workstations that provide storage, analysis, processing and interaction with the operator. Software - SCADA.
OMAC Open Systems Concepts
Open architecture for hardware and software integration
Modular architecture
Scalability, reconfiguration for specific tasks
economy
Easy to maintain architecture
Question #19
"Information technologies in education"
In the process of informatization of education, it is necessary to highlight the following aspects:
Methodological. Here the main problem is the development of the basic principles of the educational process, corresponding to the modern level of information technology.
Economic. The economic basis of the information society is the branches of the information industry. There is an intensive process of formation of the world "information economy", which consists in the globalization of information, information technology and telecommunications markets.
Technical. At present, a fairly large number of software and technical developments that implement individual IT have been created and implemented. But at the same time, various methodological approaches are used, incompatible technical and software tools, which makes it difficult to replicate.
Technological. The technological basis of the information society is telecommunications and information technologies, which have become leaders in technological progress, an integral element of any modern technology, they generate economic growth, create conditions for the free circulation of large amounts of information and knowledge in society, lead to significant socio-economic transformations and, ultimately account, to the formation of the information society.
methodological aspect. The main advantages of modern information technologies (visibility, the ability to use combined forms of information presentation - data, stereo sound, graphic image, animation, processing and storage of large amounts of information, access to world information resources) should become the basis for supporting the education process.
The main factors affecting the efficiency of use information resources in the educational process:
1. Information overload is a reality. An excess of data causes a decline in the quality of thinking, especially among the educated members of modern society;
2. The introduction of modern information technologies is advisable if it allows you to create additional opportunities in the following areas:
Access to a large amount of educational information;
Figurative visual form of presentation of the studied material;
Support active methods learning;
Possibility of nested modular representation of information.
3. Fulfillment of the following didactic requirements:
The expediency of presenting educational material;
Sufficiency, clarity, completeness, modernity and structuredness of the educational material;
Multi-layered presentation of educational material according to the level of complexity;
Timeliness and completeness of control questions and tests;
Recording of actions during work;
Interactivity, the ability to choose the mode of working with educational material;
The presence in each subject of the main, invariant and variable parts that can be adjusted.
4. Computer support for each subject studied, and this process cannot be replaced by studying a single course in computer science.
Question #20
"Information technologies of computer-aided design."
The creation of CAD products takes place in the following areas:
Universal graphics package for flat drawing, volumetric modeling and photorealistic rendering;
Open graphical environment for building applications
Graphics editor and graphical application environment
Open design environment;
CAD for non-professionals (home use)
The most complete possibilities of a CAD product at the level of a universal graphics package can be traced on the example of AutoCAD 2000. Features:
Ability to work with multiple drawing files in one session without loss of performance;
Contextual pop-up menu that includes a group of clipboard operations
The presence of modeling tools that allow you to edit solid objects at the level of edges and faces;
Ability to access the properties of objects;
Ability to select, group and filter objects by types and properties;
Availability of technology for creating and editing blocks;
Ability to insert hyperlinks into the drawing;
Inclusion of a new drag-and-drop technology interface for working with blocks, external links, image files and drawings;
Control of the thickness (weight) of lines directly with reproduction on the screen;
Ability to work with layers without printing;
Visual work with dimensions and dimension styles;
Availability of controls for views and coordinate systems;
The presence of several modes of visualization from wireframe to shading;
Availability of means to ensure the accuracy of input when creating and editing;
Ability to arrange drawings and print; work with external databases;
The most promising in the field of automated testing is the use of open environments, the main value of which is the automation of the design process: the choice of the structure of the design object; necessary calculations, including geometric, etc. An example of the implementation of this approach is the SPRUT technology, implemented as a graphical shell with a changeable problem orientation. DiaCad.
However DiaCad is only an integral part of the SPRUT technology and is used in cases where it is possible to formalize the design process in a given subject environment. Where this is not possible, interactive drawing tools are used, as well as known graphical editing tools.
Question #21
"System approach to building information systems"
IC design approaches:
cascading
Spiral - continuous development of IS
Systemic
A system is a set of objects, the properties of which are determined by the relationship between the objects. Each object is like a system. The functions of an object are determined by its internal structure. The functions of the system are manifested in the process of its interaction with the external environment. Technical systems are created for a specific purpose. The goal is subjective due to the developer, but comes from the objective needs of society. IT as a system. The emergence of a problem gives rise to a future system.
A system is a finite set of functional elements and relationships between them that are isolated from the environment in accordance with the goal set within a certain time interval for its implementation.
The system approach is implemented by studying the function or structure of the system.
Structural approach - the structure displays the links between the elements of the system, taking into account their interaction in space and time. Serves to study the existing system.
Functional approach - displays the functions of the system, implemented in accordance with the goal set for it.
The structure of the system is described in:
Conceptual level - allows you to qualitatively determine the main subsystems, elements and relationships between them.
logical level– formation of a model that describes the structure of individual subsystems and the interaction between them.
The physical level is the implementation of the structure on known hardware and software.
Principles of a systematic approach:
1. The presence of a single goal for IT within the developed system.
2. Coordination of IT inputs and outputs with the environment
3. Typification of IT structures
4. standardization and interconnection of IT tools
5. Openness of IT as a system
The basic principles and patterns of design are determined by systems engineering.
System engineering is a branch of cybernetics that studies the planning, design, construction and behavior of complex IS, which are based on computers.
Design can be thought of as a cycle, each iteration of which is more detailed and less general.
Analysis->Synthesis->Evaluation->analysis…
Design properties:
Divergence is the expansion of the boundaries of the design situation in order to provide a wider space for finding a solution.
Transformation is the stage of creating principles and concepts
Convergence - covers traditional design (programming, debugging, detailing)
Question #22
"Analysis and formation of a conceptual model of the subject area."
All information describing a specific subject area must be abstracted and formalized in a certain way.
The main directions of formalization of information about the subject area are:
Classification theory based on taxonomic and meronomic description of information. The taxonomic description is based on the ideology of sets, while the meronomic description is carried out through a strictly formalized definition of classes;
A theory of measurement that offers a basis for qualitative and quantitative measurements through classification and ordinal scales;
Semiotics, which studies sign systems from the point of view of syntactic, semantic and pragmatic.
Subject area- the real world, which should be reflected in the information base.
Data- the result of monitoring the state of the subject area.
Data- a type of information characterized by a high degree of formatting, in contrast to the freer structures characteristic of speech, text and visual information
Information base(database) - a collection of data intended for joint use.
Knowledge- the result of theoretical and practical human activity, reflecting the accumulation of previous experience And characterized by a high degree of structuring.
Knowledge can be divided into three main components:
Declarative, representing a general description of the object, which does not allow them to be used without prior structuring in a specific subject area;
Conceptual (systemic) knowledge, containing, in addition to the first part, the relationship between concepts and the properties of concepts;
Procedural (algorithmic) knowledge that allows obtaining a solution algorithm.
Item- any material thing, an object of knowledge.
Property- what is inherent in objects, what distinguishes them from other objects or makes them similar to other objects. Properties are manifested in the process of interaction of objects.
sign- everything in which objects, phenomena are similar to each other or in which they differ from each other; indicator, side of an object or phenomenon, by which one can recognize, define or describe an object or phenomenon.
Attribute- an integral, essential, necessary property, a sign of an object or phenomenon, without which they cannot exist.
Thus, for the current state of information technology, it is necessary to move from an informational description of the subject area to a representation at the data level, carried out on the basis of decomposition, abstraction, and aggregation.
Decomposition- this is the division of the system (programs, tasks) into components, the combination of which allows solving this problem.
Abstraction allows you to choose the right components for decomposition.
Aggregation- the process of combining objects into a certain group, not necessarily for the purposes of classification. Aggregation is performed for some purpose.
Introduction…………………………………………………………………………...3
1. Geoinformation technologies and systems…..……..…………………..4
2. Structure and functions of GIS…………………………………………………...7
Conclusion………………………………………………………………………...9
List of used sources……………………………………………...10
INTRODUCTION
The emergence of geographic information systems is attributed to the beginning of the 60s of the XX century. It was then that the prerequisites and conditions for informatization and computerization of areas of activity related to the modeling of geographical space and the solution of spatial problems appeared. Their development is linked to research conducted by universities, academic institutions, defense departments and mapping services.
For the first time, the term "geographic information system" appeared in English-language literature and was used in two versions, such as geographic information system and geographic information system, very soon it also received the abbreviation GIS. A little later, this term entered the Russian scientific lexicon, where it exists in two equivalent forms: the original complete one in the form of a “geographic information system” and the reduced one in the form of a “geographic information system”. The first of them very soon became the official parade, and a completely reasonable desire for brevity in speech and texts reduced the last of them to the abbreviation "GIS".
Geoinformation systems and technologies
A geographic information system (GIS) is a multifunctional information system designed for collecting, processing, modeling and analyzing spatial data, displaying and using them in solving computational problems, preparing and making decisions. The main purpose of GIS is to form knowledge about the Earth, individual territories, terrain, as well as to bring the necessary and sufficient spatial data to users in a timely manner in order to achieve the greatest efficiency of their work.
Geoinformation technologies (GIT) are information technologies for processing geographically organized information.
The main feature of a GIS, which determines its advantages in comparison with other AIS, is the presence of a geoinformation basis, i.e. digital cards (CC), giving necessary information about the earth's surface. At the same time, the Central Committee must ensure:
accurate binding, systematization, selection and integration of all incoming and stored information (single address space);
complexity and clarity of information for decision-making;
opportunity dynamic simulation processes and phenomena;
the possibility of automated solution of problems related to the analysis of the characteristics of the territory;
the ability to quickly analyze the situation in emergency cases.
The history of the development of GIT goes back to the work of R. Tomleson on the creation of the Canadian GIS (CGIS), carried out in 1963-1971.
In a broad sense, GIT is data sets and analytical tools for working with coordinated information. GIT is not information technology in geography, but information technology for processing geographically organized information.
The essence of GIT is manifested in its ability to associate with cartographic (graphic) objects some descriptive (attributive) information (primarily alphanumeric and other graphic, sound and video information). As a rule, alphanumeric information is organized in the form of relational database tables. In the simplest case, each graphical object (and usually point, line and area objects are distinguished) is assigned a table row - an entry in the database. The use of such a connection, in fact, opens up such rich functionality for the GIT. These capabilities vary from system to system, of course, but there is a basic set of functionality that is typically found in any GIT implementation, such as the ability to answer "what is this?" questions. indicating the object on the map and "where is it?" selection on the map of objects selected by some condition in the database. The basic can also include the answer to the question "what's next?" and its various modifications. Historically, the first and most universal use of GIT is information retrieval, reference systems. Thus, GIT can be considered as a kind of extension of database technology for coordinated information. But even in this sense, it is new way integration and structuring of information. This is due to the fact that in the real world most of the information relates to objects for which their spatial position, shape and relative position play an important role, and therefore, GIT in many applications significantly expand the capabilities of conventional DBMS, since GIT is more convenient and intuitive to use. and provide the DL with their "cartographic interface" for organizing a query to the database, along with the means of generating a "graphical" report. And finally, GIT adds a completely new functionality to conventional DBMSs - the use of spatial relationships between objects. The essence of GIT is manifested in its ability to associate with cartographic (graphic) objects some descriptive (attributive) information (primarily alphanumeric and other graphic, sound and video information). As a rule, alphanumeric information is organized in the form of relational database tables. In the simplest case, each graphical object (point, line or area) is assigned a table row - an entry in the database. Using this connection provides the rich functionality of GIT. These capabilities vary from system to system, of course, but there is a basic set of functionality that is typically found in any GIT implementation, such as the ability to answer "what is this?" questions. indicating the object on the map and "where is it?" selection on the map of objects selected by some condition in the database. The basic can also include the answer to the question "what's next?" and its various modifications. Historically, the first and most universal use of GIT is information retrieval, reference systems.
Thus, GIT can be considered as a kind of extension of database technology for coordinated information. But even in this sense, it represents a new way of integrating and structuring information. This is due to the fact that in the real world most of the information refers to objects for which their spatial position, shape and relative position play an important role. Consequently, GIT in many applications significantly expand the capabilities of conventional DBMS.
GIT, like any other technology, is focused on solving a certain range of tasks. Since the areas of application of GIS are quite wide (military affairs, cartography, geography, urban planning, organization of transport dispatching services, etc.), due to the specifics of the problems solved in each of them, and the features associated with a specific class of tasks being solved and with requirements for initial and output data, accuracy, technical means, etc., it is quite problematic to talk about any single GIS technology.
At the same time, any GIT includes a number of operations that can be considered as basic. They differ in specific implementations only in details, for example, software service scanning and post-scanner processing, the possibilities of geometric transformation of the original image, depending on the initial requirements and the quality of the material, etc.
Structure and functions of GIS
Geographic information systems include five key components: hardware, software, data, performers and methods.
Hardware. This is the computer running the GIS. GIS today run on various types of computer platforms, from centralized servers to stand-alone or networked desktop computers.
GIS software contains the functions and tools needed to store, analyze and visualize geographic (spatial) information. The key components of the software products are:
Tools for entering and operating geographic information database management system (DBMS or DBMS);
Tools for supporting spatial queries, analysis and visualization (display);
Graphical user interface (GUI or GUI) for easy access to tools and functions.
Data is probably the most important component. Location data (geographical data) and associated tabular data may be collected and prepared by the user or purchased from vendors. In the process of managing spatial data, a geographic information system combines (or rather combines) geographic information with other types of data. For example, already accumulated data on the population, the nature of soils, the proximity of dangerous objects, etc. (depending on the task that will have to be solved using GIS) can be associated with a specific piece of an electronic map. Moreover, in complex, distributed systems for collecting and processing information, often not existing data is associated with an object on the map, but their source, which makes it possible to monitor the state of these objects in real time. This approach is used, for example, to deal with emergencies such as forest fires or epidemics.
Performers are people who work with software products and develop plans for their use in solving real problems. It may seem strange that people working with software, are considered as an integral part of the GIS, but this has its own meaning. The point is that for effective work A geographic information system needs to adhere to the methods provided by the developers, therefore, without trained performers, even the most successful development can lose all meaning.
GIS users can be both technical specialists who develop and maintain the system, as well as ordinary employees (end users) who are helped by GIS to solve current everyday affairs and problems.
Methods. The success and efficiency (including economic) of the use of GIS largely depends on a properly drawn up plan and rules of work, which are drawn up in accordance with the specific tasks and work of each organization.
The structure of a GIS, as a rule, includes four mandatory subsystems:
1) Data entry, providing input and / or processing of spatial data obtained from maps, remote sensing materials, etc.;
2) Storage and retrieval, which allows you to quickly obtain data for appropriate analysis, update and correct them;
3) Processing and analysis, which makes it possible to evaluate parameters, solve computational and analytical problems;
4) Representation (issuance) of data in various forms (maps, tables, images, block diagrams, digital terrain models, etc.)
Thus, the creation of maps in the circle of "duties" of GIS is far from the first place, because in order to get a hard copy of the map, most of the functions of GIS are not needed at all, or they are applied indirectly. Nevertheless, both in world and domestic practice, GIS are widely used precisely for preparing maps for publication and, to a lesser extent, for analytical processing of spatial data or managing the flow of goods and services.
CONCLUSION
The use of geoinformation systems not only changes our ideas about the ways of knowing reality, but also makes significant adjustments to the theoretical foundations of mapping. As figuratively writes A.M. Berlyant, “electronic cards no longer smell of printing ink, but wink from the screen with bright lights of icons and chameleon-like change color depending on our desire and mood.” The synthesis of geoinformation technologies and Internet space gives grounds to talk about a special geoinformation space.
In principle, the main stages of computer mapping coincide with the stages of conventional historical research, but some specific points should also be emphasized. First of all, they are connected with the search for sources and their preparation for analysis. Spatial analysis requires, in addition to the creation of databases already familiar to the historian (mainly statistical ones), the selection of cartographic sources, and this, in turn, is impossible without an understanding of traditional methods of making maps, knowledge of the history of cartography, ideas about projections, etc. Fundamentally new for computer source science is the process of creating a source for analysis, since it involves .
Similar information.
Geoinformation technologies can be defined as a set of software and technological, methodological means of obtaining new types of information about the world. They are designed to improve the efficiency of: management processes, storage and presentation of information, processing and decision support. This consists in the introduction of geoinformation technologies in science, production, education and the application in practice of the information received about the surrounding reality.
Geoinformation technologies are new information technologies aimed at achieving various goals, including informatization of production and management processes. A feature of geographic information systems (hereinafter referred to as GIS) is that, as information systems, they are the result of the evolution of these systems and therefore include the foundations for the construction and operation of information systems. GIS as a system includes many interrelated elements, each of which is directly or indirectly connected with each other element, and any two subsets of this set cannot be independent without violating the integrity, unity of the system.
Another feature of GIS is that it is an integrated information system. Integrated systems are built on the principles of integrating the technologies of various systems. They are often used in so many different areas that their name often does not define all their capabilities and functions. For this reason, GIS should not be associated with solving problems of only geodesy or geography. "Geo" in the name of geographic information systems and technologies defines the object of research, and not the subject area of using these systems.
The integration of GIS with other information systems gives rise to their multidimensionality. In GIS, complex information processing is carried out from data collection to its storage, updating and presentation, so GIS should be considered from different perspectives.
How control systems GIS are designed to support decision making for the optimal management of land and resources, urban development, transportation and retail, use of the oceans or other spatial features. Unlike information systems, in GIS there are many new technologies for spatial data analysis, combined with electronic office technologies and optimizing solutions based on this. Because of this, GIS is an effective method for transforming and synthesizing a variety of data for management tasks.
How geosystems GIS integrate technologies for collecting information from such systems as: geographic information systems, cartographic information systems, automated mapping systems, automated photogrammetric systems, land information systems, automated cadastral systems, etc.
How database systems GIS are characterized by a wide range of data collected using different methods and technologies. At the same time, it should be emphasized that they combine the capabilities of text and graphic databases.
How simulation systems GIS uses the maximum number of modeling methods and processes used in other information systems and, first of all, in CAD.
How systems for obtaining design decisions GIS largely use the concepts and methods of computer-aided design and solve a number of special design problems that are not found in typical computer-aided design.
How information presentation systems GIS are the development of automated systems of documentary support using modern multimedia technologies. They have the means of business graphics and statistical analysis, and in addition to this, thematic mapping tools. It is the effectiveness of the latter that provides a diverse solution to problems in different industries when using data integration based on cartographic information.
How applied systems GIS is unparalleled in breadth, as it is used in transport, navigation, geology, geography, military affairs, topography, economics, ecology, etc.
How mass use systems GIS allows the use of cartographic information at the level of business graphics, which makes them available to any schoolchild or businessman, and not just a specialist geographer. That is why the adoption of many decisions based on GIS technologies is not limited to the creation of maps, but only uses cartographic data.
Organization of data in GIS. Thematic data is stored in GIS in the form of tables, so there are no problems with their storage and organization in databases. The greatest problems are the storage and visualization of graphic data.
The main class of GIS data is coordinate data containing geometric information and reflecting the spatial aspect. Basic types of coordinate data: point (nodes, vertices), line (open), contour (closed line), polygon (range, region). In practice, to build real objects, a larger amount of data is used (for example, a dangling node, a pseudo-knot, a normal node, a covering, a layer, etc.). On fig. 3.1 shows the main of the considered elements of coordinate data.
The considered data types have large quantity various connections, which can be divided into three groups:
- relationships to build complex objects from simple elements;
- relationships calculated by the coordinates of objects;
- relationships defined by specific description and semantics at data entry.
In the general case, spatial (coordinate) data models can have a vector or raster (cellular) representation, contain or not contain topological characteristics. This approach allows to classify models into three types: raster model; vector non-topological model; vector topological model. All these models are mutually convertible. Nevertheless, when obtaining each of them, it is necessary to take into account their features. In the GIS form of representation of coordinate data, there are two main subclasses of models: vector and raster (cellular or mosaic). A class of models is possible that contain characteristics of both vectors and mosaics. They're called hybrid models.
Rice. 3.1.
Graphical representation of a situation on a computer screen involves displaying various graphic images on the screen. The generated graphic image on the computer screen consists of two different parts from the point of view of the storage environment - a graphic "substrate" or a graphic background and other graphic objects. In relation to these other graphic images, the "image-substrate" is an "areal" or spatial two-dimensional image. The main problem in the implementation of geoinformation applications is the difficulty of a formalized description of a specific subject area and its display on an electronic map.
Thus, geoinformation technologies are intended for the widespread introduction into practice of methods and means of information interaction over spatio-temporal data, presented in the form of a system of electronic maps, and subject-oriented environments for processing heterogeneous information for various categories of users.
Let's take a closer look at the main graphical models.
Vector patterns widely used in GIS. They are built on vectors that occupy a part of the space, in contrast to the raster models that occupy the entire space. This determines their main advantage - the requirement for orders of magnitude less memory for storage and less time spent on processing and presentation, and most importantly - a higher accuracy of positioning and data presentation. When building vector models, objects are created by connecting points with straight lines, arcs of circles, polylines. Areal objects - areas are defined by sets of lines.
Vector models are used primarily in transport, utility, marketing GIS applications. GIS systems that work primarily with vector models are called vector GIS. In real GIS, they do not deal with abstract lines and points, but with objects containing lines and areas occupying a spatial position, as well as with complex relationships between them. Therefore, a complete vector GIS data model displays spatial data as a collection of the following main parts: geometric (metric) objects (points, lines and polygons); attributes - features associated with objects; connections between objects. Vector models (of objects) use as an elementary model a sequence of coordinates forming a line. A line is a boundary, segment, chain or arc. The main types of coordinate data in the class of vector models are defined through the base element line as follows. A point is defined as a degenerate line of zero length, a line is defined as a line of finite length, and an area is represented by a sequence of connected segments. Each section of the line can be a boundary for two areas or two intersections (nodes). The common boundary segment between two intersections (nodes) has different names that are synonymous in the GIS domain. Graph theorists prefer the term "edge" to the word "line", and use the term "vertex" to denote an intersection. The US National Standard officially sanctioned the term "chain". On some systems ( Arcinfo, GeoDraw) the term "arc" is used. Unlike ordinary vectors in geometry, arcs have their own attributes. Arc attributes designate the polygons on either side of them. In relation to arc sequential encoding, these polygons are referred to as left and right. The concept of an arc (chain, edge) is fundamental to vector GIS.
Vector models receive different ways. One of the most common is the vectorization of scanned (bitmap) images.
Vectorization- the procedure for selecting vector objects from a raster image and obtaining them in vector format. Vectorization requires high quality (distinct lines and contours) of raster images. To ensure the required clarity of the lines, sometimes you have to improve the image quality.
During vectorization, errors are possible, the correction of which is carried out in two stages:
- 1) correction of a bitmap image before its vectorization;
- 2) correction of vector objects.
Vector models display continuous objects or phenomena using discrete data sets. Therefore, we can talk about vector discretization. At the same time, the vector representation makes it possible to reflect greater spatial variability for some regions than for others, compared with a raster representation, which is due to a clearer display of boundaries and their less dependence on the original image (image) than with a raster display. This is typical of social, economic, demographic phenomena, the variability of which is more intense in a number of regions.
Some objects are vector objects by definition, such as the boundaries of the corresponding land plot, the boundaries of districts, etc. Therefore, vector models are commonly used to collect coordinate geometry data (topographic records), legal boundary data, and so on.
Features of vector models: in vector formats, a dataset is defined by database objects. The vector model can organize the space in any sequence and gives "random access" to the data. It is easier to carry out operations with linear and point objects, for example, network analysis - the development of traffic routes along the road network, the replacement of symbols. In raster formats, a point feature must occupy an entire cell. This creates a number of difficulties related to the ratio between the size of the raster and the size of the object.
As for the accuracy of vector data, here we can talk about the advantage of vector models over raster ones, since vector data can be encoded with any conceivable degree of accuracy, which is limited only by the capabilities of the method of internal representation of coordinates. Typically, 8 or 16 decimal places (single or double precision) are used to represent vector data. Only some classes of data obtained during the measurement process correspond to the accuracy of vector data: these are data obtained by precise surveying (coordinate geometry); maps of small areas based on topographic coordinates and political boundaries defined by precise surveying.
Not all natural phenomena have characteristic clear boundaries that can be represented in the form of mathematically defined lines. This is due to the dynamics of phenomena or ways of collecting spatial information. Soils, vegetation types, slopes, wildlife habitats - all these objects do not have clear boundaries. Typically, lines on a map are 0.4 mm thick and are often considered to represent the uncertainty of an object's position. In a raster system, this uncertainty is given by the cell size. Therefore, it should be remembered that in a GIS, the size of the raster cell and the uncertainty in the position of the vector object, and not the accuracy of the coordinates, give the real indication of accuracy. To analyze relationships in vector models, it is necessary to consider their topological properties, i.e. consider topological models, which are a type of vector data models.
IN raster models discretization is carried out most in a simple way- the entire object (the study area) is displayed in spatial cells that form a regular network. Each cell of the raster model corresponds to the same size, but different characteristics (color, density) surface area. The model cell is characterized by one value, which is the average characteristic of the surface area. This procedure is called pixelation. Raster models are divided into regular, irregular And nested(recursive or hierarchical) mosaics. There are three types of flat regular tilings: square (Figure 3.2), triangle, and hexagon (Figure 3.3).
Rice. 3.2.
Rice. 3.3.
The square shape is convenient for processing large amounts of information, the triangular shape is for creating spherical surfaces. Triangular networks of irregular shape are used as irregular mosaics ( Triangulated Irregular Network - TIN) and Thyssen polygons (Figure 3.4). They are convenient for creating digital models of terrain marks from a given set of points.
Thus, the vector model contains information about the location of the object, and the raster model contains information about what is located at one or another point of the object. Vector models are binary or quasi-binary.
Rice. 3.4.
If the vector model provides information about where this or that object is located, then the raster model provides information about what is located in one or another point of the territory. This determines the main purpose of raster models - the continuous display of the surface. In raster models, a two-dimensional element of space, a pixel (cell), is used as an atomic model. An ordered set of atomic models forms a raster, which, in turn, is a model of a map or geo object. Vector models are binary or quasi-binary. Bitmaps allow you to display halftones and color shades. Typically, each raster element or each cell should have only one density or color value. This does not apply in all cases. For example, when the boundary of two coverage types can pass through the center of a raster element, the element is given a value that characterizes the majority of the cell or its center point.
Some systems allow multiple values for a single raster element. For raster models, there are a number of characteristics: resolution, value, orientation, zones, position.
Permission- the minimum linear size of the smallest portion of the displayed space (surface), displayed by one pixel. Pixels are usually rectangles or squares, less often triangles and hexagons are used. A raster with a higher resolution has smaller size cells. A high resolution implies an abundance of details, many cells, minimum size cells.
Meaning- an element of information stored in a raster element (pixel). Since typed data is used during processing, i.e. the need to define raster model value types. The type of values in the raster cells is determined both by the real phenomenon and by the features of the GIS. In particular, in different systems you can use different value classes: integers, real (decimal) values, literal values. Integer numbers can serve as optical density characteristics or codes indicating a position in an attached table or legend. For example, the following legend is possible, indicating the name of the soil class: O - empty class, 1 - loamy, 2 - sandy, 3 - gravelly, etc.
Orientation- the angle between the direction to the north and the position of the columns of the raster.
Zone raster model includes cells adjacent to each other that have the same value. A zone can be individual objects, natural phenomena, ranges of soil types, elements of hydrography, etc. To indicate all zones with the same value, the concept of "zone class" is used. Naturally, not all image layers may have zones. The main characteristics of the zone are its meaning and position.
buffer zone- a zone, the boundaries of which are removed at a known distance from any object on the map. Buffer zones of various widths can be created around selected objects based on tables of associated characteristics.
Position usually given by an ordered pair of coordinates (row number and column number) that uniquely define the position of each element of the displayed space in the raster. When comparing vector and raster models, we note the convenience of vector models for organizing and working with object relationships. However, by using simple tricks, such as including relationships in attribute tables, you can organize relationships in raster systems as well.
Questions need to be addressed accuracy display in raster models. In raster formats, in most cases it is not clear whether the coordinates refer to the center point of a pixel or to one of its corners. Therefore, the anchoring accuracy of a raster element is defined as 1/2 of the width and height of the cell.
Raster models have the following advantages:
- The raster does not require a preliminary acquaintance with the phenomena, the data is collected from a uniformly distributed network of points, which makes it possible in the future to obtain objective characteristics of the objects under study based on statistical processing methods. Due to this, raster models can be used to study new phenomena about which no material has been accumulated. Due to its simplicity, this method is most widely used;
- raster data is easier to process using parallel algorithms and thus provide higher performance compared to vector data;
- some tasks, such as creating a buffer zone, are much easier to solve in raster form;
- many raster models allow you to enter vector data, while the reverse procedure is very difficult for vector models;
- rasterization processes are much simpler algorithmically than vectorization processes, which often require expert judgment.
A digital map can be organized into multiple layers (overlays or underlay maps). Layers in GIS represent a set of digital cartographic models built on the basis of association (typing) of spatial objects that have common functional features. The set of layers forms the integrated basis of the graphical part of the GIS. An example of integrated GIS layers is shown in fig. 3.5.
Rice. 3.5.
An important point in the design of a GIS is the dimension of the model. Two-dimensional coordinate models (2D) and three-dimensional (3D) are used. Two-dimensional models are used to build maps, while three-dimensional models are used for modeling geological processes, designing engineering structures (dams, reservoirs, quarries, etc.), modeling gas and liquid flows.
There are two types of 3D models:
- 1) pseudo-three-dimensional, when the third coordinate is fixed;
- 2) true three-dimensional representation.
Most modern GIS perform complex information processing:
- collection of primary data;
- accumulation and storage of information;
- various types of modeling (semantic, simulation, geometric, heuristic);
- automated design;
- documentation support.
The many tasks that arise in life have led to the creation of various GIS that can be classified according to the following criteria:
- 1) by functionality:
- full-featured GIS general purpose,
- specialized GIS are focused on solving a specific problem in any subject area,
- information and reference systems for home and information and reference use.
The functionality of a GIS is also defined architectural principle their constructions:
- closed systems - do not have expansion options, they are able to perform only the set of functions that is uniquely defined at the time of purchase,
- open systems are easy to adapt, expandable, as they can be completed by the user himself using a special apparatus (embedded programming languages);
- 2) spatial (territorial) coverage:
- global (planetary),
- nationwide,
- regional,
- local (including municipal);
- 3) problem-thematic orientation:
- general geographic,
- environmental and nature management,
- sectoral (water resources, forest management, geological, tourism, etc.);
- 4) the way geographic data is organized:
- vector,
- raster,
- vector-raster GIS.
As data sources for the formation of GIS are:
- cartographic materials(topographic and general geographical maps, maps of administrative-territorial division, cadastral plans, etc.). Information received from maps is georeferenced, so it is convenient to use it as a base GIS layer. If there are no digital maps for the study area, then the graphic originals of the maps are converted into digital view;
- remote sensing data(hereinafter referred to as RSD) are increasingly being used to form GIS databases. ERS primarily includes materials obtained from space carriers. For remote sensing, a variety of technologies for obtaining images and transmitting them to Earth are used, carriers of imaging equipment (spacecraft and satellites) are placed in different orbits and equipped with different equipment. Thanks to this, images are obtained that differ in different levels of visibility and detail in the display of objects of the natural environment in different spectral ranges (visible and near infrared, thermal infrared and radio range). All this leads to a wide range of environmental problems solved with the use of remote sensing. Remote sensing techniques include aerial and ground surveys and other non-contact methods such as hydroacoustic seabed surveys. The materials of such surveys provide both quantitative and qualitative information about various objects of the natural environment;
- materials of field surveys of territories include data from topographic, engineering and geodetic surveys, cadastral surveys, geodetic measurements of natural objects performed by levels, theodolites, electronic total stations, GPS receivers, as well as the results of surveys of territories using geobotanical and other methods, for example, studies on the movement of animals, soil analysis and etc.;
- statistical data contain data from state statistical services for various sectors of the national economy, as well as data from stationary measuring observation posts (hydrological and meteorological data, information on environmental pollution, etc.));
- literature data(reference publications, books, monographs and articles containing a variety of information on certain types of geographical objects).
In GIS, only one type of data is rarely used, most often it is a combination of various data for any territory.
The main areas of GIS use:
- electronic cards;
- urban economy;
- state land cadastre;
- ecology;
- remote sensing;
- economy;
- special military systems.
In practice, GIS such as Arcinfo And ArcView GIS. Both systems were developed by an American company ESRI(www.esri.com, www.dataplus.ru) and are very common in the world.
From relatively simple Western GIS, which began their pedigree with the analysis of territories in the amount necessary for business and relatively simple applications, we can call the system mapinfo, which is also very widespread in the world. This system is progressing very quickly and today can compete with the most advanced GIS.
Corporation Intergraph(www.intergraph.com) supplied by GIS mge, based on an AutoCAD-like system microstation, produced in turn by the company Bendy. System MGE is a whole family of various software products that help to solve the largest number of problems that exist in the field of geoinformatics.
All of these products also have Internet GIS servers that allow you to publish digital maps on the Internet. True, we have to talk only about viewers, since today it is possible to provide editing of topological maps from the side remote client The Internet is impossible due to the underdevelopment of both GIS and Internet technologies.
Just recently entered the GIS market and microsoft, thus confirming that GIS will become in the near future such a system that every user who has the slightest respect for himself should have on his computer, as he has today excel or word. Microsoft released a product mappoint (Microsoft MapPoint 2000 Business Mapping Software), which will be included in office 2000. This component of the office product will focus primarily on business planning and analysis.
Repetition of the concept Arcinfo, but much inferior to the latter in terms of functional completeness is the domestic system GeoDraw, developed at TsGI IGRAN (Moscow). Its capabilities are limited today mainly by small-scale maps. From our point of view, the “elder” of domestic geoinformatics, GIS, looks much “stronger” here Sinteks ABRIS. In the latter, functions for the analysis of spatial information are well represented.
In geology, the position of GIS PARK (Laneco, Moscow) is strong, which also implements unique methods for modeling the corresponding processes.
Two domestic systems can be considered the most "advanced" in the field of presentation and duty of large-scale saturated maps of cities and master plans of large enterprises: GeoCosm(GEOID, Gelendzhik) and InGeo (CSI Integro, Ufa, www.integro.ru). These systems are among the youngest and therefore were developed immediately using the most modern technologies. And the InGeo system was developed not so much by surveyors as by specialists who consider themselves professionals in the field of simulation modeling and cadastral systems.
In general, almost every organization in Russia creates its own GIS. However, this process is very difficult, and the probability of its completion unsuccessfully is incomparably higher than the probability of a problem-free implementation, not to mention the possibility of a commercial product that allows alienation from developers.
I must say that such GIS samples mainly get to Russia that are focused either on working mainly with small-scale maps (for example, M1: 1000000 - M1: 50000), or on business analysis of geographically distributed information, moreover, for displaying a map in such systems the task of meeting all the necessary standards for the presentation of cartographic information is not set.
At the forefront of geoinformatics - in the field of work with very rich and cumbersome large-scale (M1:2000 or M1:500) city maps, such Western GIS are not very well adapted. Other GIS, which are designed to model complex dynamic processes occurring in urban areas, or physical processes in engineering communications, cost many thousands of dollars for each workplace, and therefore the prospects for their sales in Russia during the crisis are very poor. They are practically not imported into our country. Mostly not the most developed products are sold, which are difficult to apply at the city level to the extent that it is necessary for most city services.
Here are some GIS that may be of interest.
The most well-proven for working with small-scale "natural" maps (geology, agriculture, navigation, ecology, etc.) are GIS such as ArcInfo and ArcView GIS. Both systems were developed by the American company ESRI (www.esri.com., www.dataplus.ru.) and are very common in the world.
Of the relatively simple Western GIS, which began their lineage with the analysis of territories in the amount necessary for business and relatively simple applications, one can name the MapInfo system, which is also very widespread in the world. This system is progressing very quickly and today can compete with the most advanced GIS.
Intergraph Corporation (www.intergraph.com) supplies the MGE GIS based on the AutoCAD-like MicroStation system, produced in turn by Bently. The MGE system is a whole family of various software products that help to solve the largest number of problems that exist in the field of geoinformatics.
All of these products also have Internet GIS servers that allow you to publish digital maps on the Internet. True, we have to talk only about viewers, since today it is impossible to provide editing of topological maps from the side of a remote Internet client due to the underdevelopment of both GIS and Internet technologies.
Literally recently, GIS and Microsoft entered the market, thereby confirming that GIS will become in the near future such a system that every user with little or no self-respect should have on his computer, as he has Excel or Word today. Microsoft released the MapPoint product (Microsoft MapPoint 2000 Business Mapping Software), which was included in Office 2000. This component of the office product will focus mainly on business planning and analysis.
Domestic gis
A repetition of the ArcInfo concept, but much inferior to the latter in terms of functional completeness, is the domestic GeoDraw system developed at the TsGI IGRAN (Moscow). Its capabilities are limited today mainly by small-scale maps. From our point of view, the "elder" of domestic geoinformatics, GIS Sinteks ABRIS, looks much "stronger" here. In the latter, functions for the analysis of spatial information are well represented.
In geology, the positions of GIS PARK (Laneco, Moscow) are strong, which also implements unique methods for modeling the corresponding processes.
Two domestic systems can be considered the most "advanced" in the field of presentation and maintenance of large-scale saturated maps of cities and master plans of large enterprises: GeoCosm (GEOID, Gelendzhik) and InGeo (CSI "Integro", Ufa, www.integro.ru ). These systems are among the youngest and therefore were developed immediately using the most modern technologies. And the InGeo system was developed not so much by surveyors as by specialists who consider themselves professionals in the field of simulation modeling and cadastral systems.
In general, almost every organization in Russia creates its own GIS. However, as we wanted to show in this article, this process is very difficult, and the probability of its completion unsuccessfully is incomparably higher than the probability of a problem-free implementation, not to mention the possibility of a commercial product that allows alienation.
Geoinformatics(GIS tehnology, geo-informatics) - science, technology and production activities for scientific substantiation, design, creation, operation and use of geographic information systems, for the development of geoinformation technologies, or GIS technologies (GIS tehnology), on applied aspects, or applications GIS (GIS application) for practical or geoscientific purposes.
Geoinformation technologies- (GIS technology) - syn. GIS technologies are the technological basis for the creation of geographic information systems, which makes it possible to implement the functionality of a GIS.
Geographic Information System(geographic(al) information system, GIS, spatial information system) - syn. geographic information system, GIS - an information system that provides the collection, storage, processing, access, display and distribution of spatially coordinated data (spatial data).
GIS can be used:
a) as information systems (visual databases), whose task is to store information about spatial objects and issue it upon request with visualization of objects;
b) as an information system with elements of processing the results of topographic and geodetic surveys with their further entry into the database;
c) as complexes serving the full cycle for the production of cartographic products, starting with the collection and processing of initial information and ending with the preparation of original layouts of maps.
GIS requires powerful hardware: mass storage devices, display subsystems, high-speed network equipment.
IN The basis of any GIS is information about any part of the earth's surface: a country, a continent or a city. The database is organized as a set of layers of information. The main layer contains a geo-referenced map of the area (topographic base). Other layers are superimposed on it, carrying information about the objects located in the given territory: communications, industrial facilities, land plots, soils, utilities, land use, and others. In the process of creating and superimposing layers on top of each other, the necessary connections are established between them, which allows you to perform spatial operations with objects through modeling and intelligent data processing. As a rule, information is presented graphically in vector form, which reduces the amount of stored information and simplifies visualization operations. Graphical information is associated with textual, tabular, calculated information, coordinate binding to a map of the area, video images, audio comments, a database with a description of objects and their characteristics. GIS allows you to extract any type of data, visualize them. Many GIS include analytical features that allow you to model processes based on cartographic information.
The main areas of application of GIS:
Geodetic, astronomical-geodetic and gravimetric works;
Topological works;
Cartographic and map publishing works;
aerial photography;
Formation and maintenance of data banks of the above works for all levels of government of the Russian Federation, to display the political structure of the world, an atlas of roads and railways, the borders of the Russian Federation and foreign countries, economic zones, etc.
But no matter how complex the functions performed by a particular GIS are, in any case, the information system works with spatial objects and various types their presentations. Therefore, we can say: the data processed by GIS is nothing but electronic maps. An electronic map is organized as a set of layers, the functional purpose of which is to combine spatial objects (more precisely, a set of data characterizing them in a visual database) that have any general properties. These properties can be:
Belonging to one type of spatial objects (a layer of buildings, a layer of hydro facilities, a layer of administrative boundaries, etc.);
Display on the map in one color;
Representation on the map with the same graphical primitives (lines, points, polygons), etc.
In addition, the layer can add properties to objects. For example, objects belonging to a layer cannot be edited, deleted, shown, etc.
The multilayer organization of an electronic map with a flexible layer management mechanism allows you to combine and display a much larger amount of information than on a conventional map. As separate layers, you can also represent the original data, in the process of processing which a map is obtained. The data on these layers, as a rule, can be processed both interactively and semi-automatically and automatically.
GIS contains data about spatial objects in the form of their digital representations (vector, raster, quadrotomy and others), includes a set of GIS functionalities corresponding to the tasks, in which the operations of geoinformation technologies, or GIS technologies (GIS tehnology) are implemented, supported by software, hardware, information, legal, personnel and organizational support.
Vector graphics - the earliest form computer graphics. Its main primitives are point (node), line (edge), and plane. Because point and plane are special cases of line, it is common to refer to vector graphics as line graphics.
Raster graphics are the newest form of computer graphics. The central element is a pixel. Currently, due to the high resolution of bitmap screens, a distinction is made between passive and interactive visualization. The distribution of halftone dots is a hierarchical method of handling in spatial data storage, wherein the area to be processed is divided into halftone cells of the same size. The reference is given through row and column indices, which can be organized as matrices.
By territorial coverage distinguish between global or planetary GIS (global GIS), subcontinental GIS, national GIS, often with the status of state, regional GIS (regional GIS), sub-regional GIS and local or local GIS (local GIS).
GIS differ in the subject area of information modeling, for example, urban GIS, or municipal GIS, MGIS (urban GIS), environmental GIS (environmental GIS), etc.; among them, a special name, as especially widespread, was given to land information systems.
Problem Orientation A GIS is determined by the tasks it solves (scientific and applied), among them is the inventory of resources (including the cadastre), analysis, assessment, monitoring, management and planning, decision support.
Integrated GIS, IGIS (integrated GIS, IGIS) combine the functionality of GIS and digital image processing systems (remote sensing materials) in a single integrated environment.
Polyscale or scale-independent GIS (multiscale GIS) are based on multiple, or multiscale representations of spatial objects (multiple representation, multiscale representation), providing graphical or cartographic reproduction of data at any of the selected scale levels based on a single data set with the highest spatial resolution.
Spatio-temporal GIS (spatio-temporal GIS) operate with spatio-temporal data.
The implementation of geoinformation projects (GIS project), the creation of a GIS in the broad sense of the word, includes the following steps:
Pre-project study (feasibility stady), including the study of user requirements (user requirements) and the functionality of the GIS software used,
Feasibility study, assessment of the cost/benefit ratio (costs/benefits);
GIS system design (GIS design), including the pilot project stage (pilot-project), GIS development (GIS development);
Testing on a small territorial fragment, or test area (test area),
Prototyping or creating a prototype, prototype (prototype);
GIS implementation, operation and use.
Scientific, technical, technological and applied aspects of the design, creation and use of GIS are studied by geoinformatics.
The GIS software core can be divided into parts: instrumental geoinformation systems, viewers, vectorizers, tools spatial modeling, means of remote sensing.
Instrumental geographic information systems provide input of geospatial data, storage in structured databases, implementation of complex queries, spatial analysis, output of hard copies.
Viewers are designed to view the information entered earlier and structured by access rights, while allowing you to perform information queries from databases generated using instrumental GIS, including outputting cartographic data to a hard drive.
Vectorizers raster cartographic images are designed to input spatial information from the scanner, including semi-automatic means of converting raster images into vector form.
Spatial modeling tools operate with spatial information focused on particular tasks such as modeling the process of spreading pollution, modeling geological phenomena, analyzing the terrain.
Remote sensing facilities designed for processing and decoding digital images of the earth's surface obtained from aircraft and artificial satellites.
best product in the professional GIS world, Arc/Info for Windows NT is considered.
Of the many programs that can be called GIS software the following can be recommended: Map Objects v.1.2; Map Objects Internet Server; Spatial Data Engine v.2.1.1.
GIS viewers are programs that perform only the functions of viewing and converting various formats used for GIS. Two such products are most commonly used: WinGIS v.3.2 (PROGIS); Business Map Pro (ESRI).
TO desktop GIS include MapInfo Professional (MapInfo); PC ARC/INFO v.3.5.1 (ESRI); ArcView GIS v.3.0a (ESRI); Spatial Analyst (ESRI); Network Analyst (ESRI).
TO spatial processing systems include Surfer v.6.0 (Golden Software, Inc.) and NRTSGIT authorings.
Geographic information system map info was developed in the late 80s by Mapping Information Systems Corporation (U.S.A.). GIS MapInfo works on PC platforms (Windows 3.x/95/98/NT), PowerPC (MacOS), Alpha, RISC (Unix). MapBasic data files and programs are portable from platform to platform without conversion.
The MapInfo package is specially designed for processing and analyzing information that has an address or spatial reference. The operations that support communication with the database are so simple that a little experience with any database is enough to immediately use the possibilities of computer mapping in your field of activity. MapInfo is a mapping database. The built-in powerful SQL MM query language, thanks to the geographical expansion, allows you to organize selections taking into account the spatial relationships of objects, such as remoteness, nesting, overlap, intersection, area, etc. Database queries can be saved as templates for reuse. MapInfo has the ability to search and plot objects on the map by coordinates, address, or index system.
MapInfo allows you to edit and create electronic maps. Digitization is possible both with the help of a digitizer (graphic tablet) and from a scanned image. MapInfo supports GIF, JPEG, TIFF, PCX, BMP, TGA (Targa), BIL (SPOT satellite photos) raster formats. MapInfo Universal Translator imports maps created in formats of other geoinformation and CAD systems: AutoCAD (DXF, DWG), Intergraph/MicroStation Design (DGN), ESRI Shape file, AtlasGIS, ARC/INFO Export (E00). Digital information from GPS (global positioning navigation devices) and other electronic devices is entered into MapInfo without the use of additional programs.
In MapInfo, you can work with data in Excel formats, Access, xBASE, Lotus 1-2-3 and text format. Data file conversion is not required. Cartographic objects are added to the records in these files. Data of different formats can be used simultaneously in one session. From MapInfo you can access remote databases ORACLE, SYBASE, INFORMIX, INGRES, QE Lib, DB2, Microsoft SQL, etc.
MapInfo has 5 main window types: Map, List, Legend, Graph, and Report. In the window Map tools for editing and creating cartographic objects, scaling, changing projections and other functions for working with a map are available. Information related to cartographic objects can be presented in the form of a table in the window List. In the window Schedule data from tables can be displayed in the form of graphs and charts of various types. In the window Legend symbols of objects on the map and thematic layers are displayed. In the window Report tools are provided for scaling, layout, and saving templates for multi-sheet maps. Working with MapInfo, you can generate and print reports with map fragments, lists, graphs and labels. When printing, MapInfo uses standard operating system drivers.
Thematic cartography is a powerful tool for analyzing and visualizing spatial data. On the thematic map, it is easy to understand the connections between various objects and see trends in the development of various phenomena. In MapInfo, you can create thematic maps of the following main types: cartograms, column and pie charts, icon method, point density, qualitative background method, and continuous surface-grid. A combination of thematic layers and methods of buffering, zoning, merging and splitting objects, spatial and attribute classification allows you to create synthetic multicomponent maps with a hierarchical legend structure.
MapInfo is an open system. The MapBasic programming language allows you to create your own GIS based on MapInfo. MapBasic supports data exchange between processes (DDE, DLL, RPC, XCMD, XFCN), integration into the SQL query program. The joint use of MapInfo and the MapBasic development environment allows everyone to create their own GIS for solving specific application problems.
Localization of the MapInfo/MapBasic Professional package has been done so that it works with Russian data without problems, i.e. sorting and indexing is carried out according to the rules of the Russian language. The delivery of the Russian version of MapInfo includes libraries of conventional symbols, a number of utilities and CAD functions that expand the capabilities of the package, in accordance with the requirements of the Russian market of geographic information systems.
