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Final Paper
“Geographic information system in the road sector”
Student:
Barysenka Dzianis
丹尼斯
Student id:
21806280
Submitted to:
Assoc. Prof. 张明媛
2018, Dalian
Contents
1. Introductiom........................................................................................................3
2. GIS tasks related to data analysis and visualization..............................................................5
3. The use of GIS in practice………………………………………………………………….....6
4. GIS in transport……………………………………………………………………….………7
5. GIS in the road sector…………………………………………………………………............9
6. Conclusion………………………………………………………………………….…………13
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1. Introduction
In our age of information technology boomers, one can observe the massive introduction
of spatial information processing. And, of course, geographic information systems (GIS) play a
major role in this matter.
Perhaps the main purpose of GIS is the most "natural" (for humans) presentation of both
spatial information and any other information related to objects located "in space" (so-called
attribute information). The ways of presenting attribute information are different: it can be a
numeric value from a sensor, a table from the database (both local and remote) about the
characteristics of the object, its photograph, or a real video image.
Geographic information systems have become a common tool to help solve various
information tasks. They are implemented and successfully work in areas such as automatic
mapping, resource management and management. However, very few GIS can ensure the daily
operations of the maintenance and operation of transport networks. The problem lies in the
processing and inclusion in the system of a different nature and source of information creation.
The objects included in the GIS, as a rule, in addition to geodetic data, also have
technological characteristics presented in the form of various databases. But in addition to these
reference characteristics, additional information is needed related to the type of representation of
cartographic information, technological calculations and the inclusion of technical
documentation in the information system.
To solve these problems successfully, software is needed that allows creating a unified
information environment on the basis of GIS, including both standard GIS functions and
technological ones related to CAD and modern data acquisition methods (GPS).
2. The main goal of the implementation of such an information system is to organize a
general solution of GIS and CAD problems with a high degree of automation of graphic
work, accumulation and systematization of information in the form of databases, charts
and maps, efficient storage and retrieval of information in the form of electronic archives.
In addition, the system should be provided with the continuous development of
functionality for solving new problems. Reference information and regulatory data
should be presented on real cartographic material with the possibility of issuing a "hard
copy" of both graphic and textual information. According to this task, it is necessary to
enter any configurations of transport networks into a computer, linking them to city
facilities, and further monitor any changes in the network using a monitoring system,
perform calculations on maintenance, repair, and simulate various distribution options for
traffic flows. No less important is the support of engineering documentation necessary to
maintain the current state of road networks.
At the stage of entering information, GIS is of great assistance in the visual presentation
of primary information, here there is much in common with the systems of automated control of
production and other objects (CAD and ACS). If a complex object can be represented in the form
of a scheme, then a GIS can be a convenient interface for accessing information from its sources.
For example, it may be a diagram of the transport network (roads, railways, pipelines). In this
case, using the GIS, the user can point the cursor to a certain element of the scheme and get
information about the characteristics and condition of the corresponding object: the diameter and
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thickness of the pipe walls, the gauge, the presence of trains on the stretch, the type of road
surface, the well productivity, the “history” of creation , inspections and repairs, etc. It is also
important that GIS contain convenient tools for creating and editing such schemes and, of
course, for organizing communication with the primary sources of information. A separate
direction, closely related to GIS, is the means of geolocation (GPS), which provide with a given
accuracy the determination of the geographical position of objects.
GIS saves information about the real world in the form of a set of thematic layers that are
combined based on geographic location. This simple but very flexible approach proved its value
in solving various real-world tasks: to track the movement of vehicles and materials, to display
in detail the real situation and planned activities, to simulate the global circulation of the
atmosphere.
Any geographic information contains information about the spatial position, whether it is
georeferencing or other coordinates, or links to an address, postal code, electoral district or
census district, land or forest identifier, road name, etc.
When using such links, a procedure called geocoding is used to automatically locate the
objects. With its help, you can quickly identify and see on the map where the object or
phenomenon you are interested in, such as the house where your friend lives or the organization
you need, where an earthquake or flood occurred, which route is easier and faster to get to your
destination or at home.
In GIS, it is most convenient to use a relational structure, in which data is stored in
tabular form. This simple approach is quite flexible and is widely used in many, both GIS and
non-GIS applications.
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2. GIS tasks related to data analysis and visualization.
Request and analysis. In the presence of GIS and geographic information, you can get
answers to simple questions (Who is the owner of this section of the road? At what distance are
the road service objects located from each other? Where is the intersection you are interested in?)
And more complex requests that require additional analysis (Where are the places for the
construction of new facilities? How will the construction of a new road affect traffic. With the
help of GIS, you can identify and set patterns for searching, play scenarios of the "what if" type.
Modern GIS has many powerful tools for analysis, two of which are most significant: proximity
analysis and overlay analysis.
To analyze the proximity of objects to each other in a GIS, a process called buffering is
used. It helps to answer questions like: How many railway crossings are within 100 km from the
beginning of the road? What is the intensity of traffic on a road in a section within 5 km of a
given traffic interchange?
The overlay process involves the integration of data located in different thematic layers.
In the simplest case, this is a display operation, but for a number of analytical operations, data
from different layers are physically combined. Overlaying, or spatial association, allows, for
example, to integrate data on soils, slope, vegetation and land tenure with land tax rates.
Visualization. For many types of spatial operations, the end result is the presentation of
data as a map or a graph. A map is a very efficient and informative way of storing, presenting
and transmitting geographic (spatially referenced) information. Previously, maps were created
for centuries. GIS provides new amazing tools that expand and develop the art and scientific
foundations of cartography. With its help, the visualization of the maps themselves can be easily
supplemented with reporting documents, three-dimensional images, graphs and tables,
photographs and other means, for example, multimedia.
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3. The use of GIS in practice
Make spatial queries and analyze. The ability of GIS to search databases and perform
spatial queries has allowed many companies to save millions of dollars. GIS helps to reduce the
time to receive responses to customer requests; identify areas suitable for the required activities;
identify relationships between different parameters (for example, soil, climate and crop yields);
identify the places of electrical breaks. Realtors use GIS to search, for example, all houses in a
certain area with slate roofs, three rooms and 10-meter kitchens, and then give a more detailed
description of these buildings. The request can be refined by the introduction of additional
parameters, such as cost. You can get a list of all houses that are located at a certain distance
from a certain highway, a forest-park area or a place of work.
Improve integration within the organization. Many organizations using GIS have found
that one of its main advantages lies in new opportunities for improving the management of their
own organization and its resources based on the geographical association of available data and
the possibility of their sharing and coordinated modification by different departments. The
possibility of sharing and constantly expanding and corrected by different structural units of the
database allows to increase the efficiency of work of each unit and the organization as a whole.
For example, a company engaged in engineering communications can clearly plan repair or
maintenance work, starting with obtaining complete information and displaying relevant areas,
such as water mains, on a computer screen (or on paper copies), and ending with the automatic
identification of the inhabitants affected and notifying them of the timing of the alleged outage or
interruption of the water supply.
Making more informed decisions. GIS, like other information technologies, confirms the
well-known saying that better information helps to make a better decision. However, GIS is not a
tool for issuing decisions, but a tool to help speed up and improve the efficiency of the decisionmaking procedure, providing answers to queries and functions for analyzing spatial data,
presenting the results of the analysis in a visual and easy-to-understand way. GIS helps, for
example, in solving such tasks as providing a variety of information at the request of planning
authorities, resolving territorial conflicts, choosing the best (from different points of view and
according to different criteria) places for placing objects, etc. The information required for
decision-making can be presented in a concise cartographic form with additional text
explanations, graphs and diagrams. The availability of information that is accessible to
perception and generalization allows the responsible employees to concentrate their efforts on
finding a solution without spending significant time collecting and comprehending available
heterogeneous data. You can quickly consider several solutions and choose the most effective
and effective.
Create maps. Maps in GIS have a special place. The process of creating maps in GIS is
much simpler and more flexible than in the traditional methods of manual or automatic mapping.
It begins with the creation of a database. As a source of source data, you can use the digitization
of ordinary paper maps. GIS-based cartographic databases can be continuous (without dividing
into separate sheets and regions) and not related to a specific scale. On the basis of such
databases, you can create maps (in electronic form or as hard copies) to any territory, of any
scale, with the necessary load, with its selection and display with the required symbols. At any
time, the database can be updated with new data (for example, from other databases), and the
data in it can be corrected as necessary.
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4. GIS in transport
In principle, the application of geographic information systems can be found almost
everywhere. But the greatest return can be obtained where the spatial importance of the
information is of primary importance. The situation is obvious for geology, ecology,
cartography, land use, military affairs - here GIS has been working for a long time and very
successfully. The first systems were created there. In the transport sphere, these systems come in
our days. This "lag" is due to several factors. On the one hand, transport has long been operating
without the use of these systems, and an increase in the efficiency of their use is not so obvious.
On the other hand, the use of GIS in transport requires the presence of certain functionality in
these systems that is not required in other areas of GIS application. And of course, the purely
productive, more conservative nature of the transport sector plays its role, if we compare it with
ecology, which gives more space for scientific research and experimentation. Nevertheless, the
tools for creating GIS are developing, and today we already have their full arsenal for creating
full-featured transport GIS.
In general, most GIS applications, both in transport and in other areas, are determined by
their ability to relate spatial and descriptive information and the possibility of their combined
analysis. The specificity of transport (as well as telecommunications) is that for many tasks there
is no need for a whole map, just a diagram showing the objects that make up the transport
network and their relations.
In transport, GIS can be used to solve three groups of problems:
• infrastructure management and development;
• park management and logistics;
• traffic control.
Currently, GIS in the transport sector are successfully used. Here are some of the
directions:
Airports: airport property management, modeling and monitoring of noise pollution,
environmental assessment, selection of places and construction of new airport facilities,
optimization of aircraft parking, assessment and capacity planning, informing passengers about
the airport plan and its immediate surroundings.
Railways: real estate management, infrastructure management (energy supply, track
facilities, alarms and communications), train and cargo tracking, traffic analysis, monitoring and
response to emergency situations, passenger information, marketing, risk assessment, network
development planning, distribution funds for repair and development.
Highways: planning (joint analysis of traffic load and roadbed condition), design
(selection of optimal corridors for building new routes), construction (displaying the state of
construction projects and determining priorities), operation (analysis of various repair strategies
and distribution of funds, joint display and analysis of maps and construction drawings from
CAD), traffic monitoring and collection of statistics on the functioning of the subordinate road
network.
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Urban passenger transport: planning and analysis of the route network, scheduling,
tracking of rolling stock, linking schedules with other modes of transport, inventory of
equipment at stops and end points, support for the operation of power supply systems, alarm
systems and communications, preparation and analysis of crash reports, demographic analysis ,
analysis of passenger traffic and route restructuring.
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5. GIS in the road sector
Accounting for complex road facilities is not easy. For a long time, road accounting
databases are maintained in the road sector, each road has a passport. Using this kind of
information in tabular form or turning to the cumbersome paper passports of individual roads
requires a good abstract thinking and knowledge of the territory. If this is not the case, then it is
quite difficult to get a clear picture of the state of the roads, and even more so about the complex
pattern of their interconnections. In addition, road maintenance is one of the most dynamic areas,
changes in which require the constant updating of information in disparate databases and
outdated passports.
This circumstance has led to the emergence of many companies producing road atlases,
filling the gap in the timely updating of information and a visual representation of the roads.
However, paper maps are focused on the road user who needs a fairly specific range of
information that can be reflected in the atlas on a single paper map. How to be services that need
very accurate and diverse data about the roads?
Many of these services, which had long since transferred their databases to computers,
began to turn to computer graphics, that is, electronic maps and geo-information technologies,
allowing them to relate the available information to its presentation in space. Those who took the
first steps in this not simple business, could not only get a comfortable work technology, but also
became convinced of the economic advantage of reliable information.
Road management has a complex structure. The object of road facilities - roads - has its
own specific features. The specificity of roads places special demands on GIS technologies.
A road is not only a roadway along which a car rolls, but also a whole complex of
technical road structures - bridges, tunnels, ramps, road signs and roadside structures. Their
location is strictly defined: bridges over obstacles, road signs - in places where certain road
conditions change.
The construction of the road, like any other object, is preceded by large construction
survey and design work. Design materials are by far the most reliable, and in some cases the only
cartographically professional material on the road position on the ground. Road designers have
significantly outstripped their colleagues from the road service in terms of electronic maps and
have long been using electronic graphic materials. Naturally, they use CAD packages, most of
which are very convenient for creating and designing drawings, but not for electronic maps.
However, it is in these formats that detailed (large-scale) maps and plans for engineering needs
are created. As a rule, AutoCAD systems or its versions are used, which store graphics in nontopological DXF and DWG formats. Engineers are quite satisfied with these formats and the
convenience of CAD systems for design, which is quite true. For those who use GIS technology,
I would like to be able to attract and use this rich and good in quality (plausibility) graphics and
other information applied to the drawing. That is, you need the ability to access the CAD formats
and, if necessary, their "painless", with the least loss of information, conversion into a GIS
system. This will provide a fairly receipt of relevant information.
Dynamism of roads is associated with the constant growth and reconstruction of the road
network. Road maps do not reflect reality as early as 2-3 years after the circulation and are
completely become obsolete in 8-10 years. To track these changes on large-scale engineering
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materials is quite time-consuming and difficult. The most expedient way is to use remote sensing
materials - aerial and space images, the roads on which are clearly interpreted. Although the
pictures are not yet a cheap pleasure, however, replacing multi-month field surveys of the road
network with computer processing of remote sensing data may become economically viable if
not today, then in a very near future. Therefore, the ability to access remote sensing materials
should be provided in the GIS.
Roads functional purpose is to ensure the interconnection of objects of the organization of
space: settlements, industrial enterprises, recreational zones, etc. The road network is
superimposed on a specific land use system, testing and influencing the environment. The road
workers have to turn to the information of land surveyors, cadastre, geologists, ecologists,
foresters. In turn, the materials of the road workers are also in demand in other areas of the
organization and accounting of land use. In order for graphic materials on the same territory,
obtained from different sources, to be somehow comparable, it is necessary, at a minimum, to
conduct them in a single coordinate system. It is better to use the rules of reference of longitude
and latitude from the Greenwich meridian and equator already established by cartographers, that
is, in other words, to maintain a graphic database in real geographical coordinates. Here in this
CAD is not strong and these GIS functions are inferior. Most professional geographic
information systems cope well with the problem of translating maps into geographic coordinates
and certain projections.
The road network as an element of infrastructure is used in almost all types of human
activity. In addition, roads are an important factor in making many business decisions: in
organizing and optimizing transportation, construction, economic development, the location of
certain objects and so on. Many state and commercial structures apply to the materials of road
builders. Among the road workers themselves, a large number of different services work
essentially with the same road network. In order to coordinate the needs of many in obtaining
reliable and up-to-date information about roads, it makes sense to create centralized nodes of a
single database with multi-user access, including in the Internet environment. Information
systems used should provide multi-user access and update not only databases, but also charts of
maps.
The road economy is based on taking into account many factors of the development and
functioning of the territory. Without modern computer technologies, multifactor analysis of
territories is practically impossible for decision making, for example, at the choice of a new road
passenger traffic or the calculation of pollution zones. The solution of such a plan of tasks is the
prerogative of GIS technology.
Unlike other features, roads have a specific feature — linearity. The point is that the
length of the roads is not comparable to their width, therefore, conventionally, they are often
presented as lines. Accounting for events on the road is carried out in linear reference systems, in
kilometers and meters along the road. Each major road has its own “zero” of reference, from
which then the measurement system is fixed in the form of kilometer posts. It is with this
reference system (and not with the geographic coordinate) that the database is connected, which
the road workers and other services working on the roads have (for example, traffic safety
services). The technology of installation of kilometer posts is not very accurate, so kilometers
along the roads turn out to be “chopped”, that is, kilometer posts are not always 1000 meters
apart from each other. Distances can be more and less. The possibility of program linking the
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linear and geographical measurement systems is necessary, taking into account the
"conventionality" of kilometer marks on the roads.
Specially processing the information obtained by remote sensing methods using sensor
devices (various cameras on board aircraft, etc.), as well as using the receivers of the global
positioning system (GPS), you can get the axis of the road, and use GIS to create a route . The
created route using the technology of "dynamic segmentation" provides a linear binding of
objects, and the objects can be both point (pipes, gas stations, bridges) and linear (forest belt,
right of way, etc.). Thus, it is not necessary to know the geographical coordinates of road objects.
It is enough to have data on their distance from the beginning of the road or from the nearest
kilometer column with known distances between all previous columns.
Each route in a single route system is measured in linear units common to the system.
However, the origin of each road is its own route. For example, on the ring road of the Small
Moscow Ring, there are 14 sections (routes), each of which starts from zero and has its own
length. The meaning of linear measurements of roads is that now any events on the road can be
identified and identified in the system of linear measurements, as it actually happens. So, in any
database on roads there is necessarily a link to the code of the road, the kilometer and meter of
the beginning of the event and the kilometer and meter of its completion (or its length). There
can be many events on the road, and they define the most diverse aspects of the road, while not
fixing the beginning and end of the event in a line-node topology - a node. This determines, for
example, the locations of bridges and tunnels, sections of roads with different surfaces, visibility
zones, periods of construction and repair of sections of roads, etc. In the same way is tied to the
location of traffic accidents. That is, the events on the roads can be continuous (for example, the
period of road construction or high-speed traffic), broken (for example, repair sites) or individual
points (for example, road signs or traffic accidents). Databases of different events are stored as
attributive properties to road routes in the form of DBMS tables (which is being done now) and
can be maintained in different departments independently, relying on a single system of road
routes. Events can be as stable as, for example, established conventional signs on the roads, and
quite dynamic - sections of road repair or accident. The kilometer marks of events recorded in
the tables are counted nominally from the location of the pillars, and the meter values are set by
measurement on the ground. Because of the “ruberness” of kilometers in the database, there can
be paradoxical data that an event occurred at 34 km and 1004 meters! That is, between 34 and 35
kilometers more than 1000 meters, which corresponds to reality. Such situations occur not only
in Russia, but also in many other countries of the world.
One of the most promising ways to clarify the location of kilometer posts is the use of
GPS receivers, which allow you to receive signals from satellites and track coordinates in
minutes. The data received in the field are easily transferred to stationary computers and
perceived by GIS. There are more expensive, but more efficient methods of inventory of objects
along the roads from a moving car with the help of an installed video camera and special
software that promptly processes the information received.
Roads and road objects are very complex and expensive technical facilities that require
constant monitoring and consideration of their main characteristics. Naturally, with certification,
diagnostics and other works, a huge amount of heterogeneous information accumulates, which
needs to be systematized and analyzed. Here information systems based on modern computer
technologies, in particular GIS, should provide great assistance. However, the introduction of
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GIS technology occurs with difficulty. The main reasons for this state of affairs are the
following:
• Lack of clear centralized policies and concepts for the development of information
systems;
• Lack of regulatory and other documents clearly regulating the main provisions for the
creation of sectoral information systems;
• Insufficient level of interaction of road workers with other services (surveyors,
ecologists, etc.)
When creating and developing road GIS, problems arise, both peculiar to any GIS, and
specific, road. Consider some of the most serious ones:
1. The choice of the optimal data model. In the road sector, this issue is particularly acute
because of the complexity and diversity of information about road objects. The road
infrastructure GIS data model should provide support for various types of data, their reliable
storage, compatibility with other systems, etc.
2. Lack of vertical communication at all levels of information systems. The disconnection
of vertical links is due to the poor compatibility of data formats of various GIS-like systems.
3. Lack of horizontal communication between similar systems. Horizontal disunity is
explained by the lack of a unified concept for the creation and development of such systems,
when each enterprise or the division begins to create its own structure, not compatible with other
similar developments.
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6.Conclusion
Basic principles and approaches to the creation of GIS roads
• This system should be created on the basis of the adopted regulatory documents and be,
if possible, compatible with other systems (including non-expensive). This condition implies the
use of accepted classifications, numberings, etc.
• When creating a system, it is worth examining very carefully the choice of the optimal
data model, the platform used and the software.
• The system must be open, i.e. complementary and changeable
• Easy and intuitive user interface, which, as a rule, has not got rid of the psychological
barrier when working with a computer.
• Considering that the creation of such a system involves considerable time and material
costs, it is necessary to develop such a scheme for its implementation, when some results of its
work can be used at the first stage (creating maps, for example), and then only expand and adapt
it tasks. In this case, a certain amount of "unnecessary" work arises, but in the end this scheme
justifies itself.
One can be sure that such GIS will more and more take over the management of road
facilities and become an integral tool for the road builder in the information society.
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