Konsep dan Definisi Sistem Informasi Geografis

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Teknik Geomatika | Institut Teknologi Sepuluh Nopember

CM224422 – Sistem Informasi Geografis

Konsep dan Definisi Sistem Informasi

Geografis

Cherie Bhekti Pribadi

[email protected]

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Materi Perkuliahan

Minggu Sub-CPMK Materi

1 Konsep dan definisi Sistem Informasi Geografis Definisi SIG 2-3 Sistem penyimpanan data spasial serta komponen data

dalam Sistem Informasi Geografis

Data Spasial

Komponen Data Spasial 4-5 Format data dalam Sistem Informasi Geografis Format Data

Sumber Data Kualitas Data

6-7 Integrasi Data Spasial Referensi Data Spasial

Integrasi Data Spasial

8 Evaluasi Tengah Semester Materi Minggu 1-7

9-10 Perbedaan antar masing-masing data dalam format Sistem Informasi Geografis

Fitur Data Spasial 11-12 Konversi data spasial serta metode konversi yang

digunakan

Konversi Data Spasial

Metode Konversi Data Spasial 13 Proses konversi data dalam pengolahan data spasial Proses Konversi Data Spasial 14 Proses topologi data spasial beserta struktur data dalam

Sistem Informasi Geografis

Definisi Topologi Struktur Data Spasial 15 Basis data atribut dalam Sistem Informasi Geografis Basis Data Atribut

16 Evaluasi Akhir Semester Materi Minggu 8-16

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Spatial Thinking

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Spatial Thinking

The objective of this section is to illustrate how we think geographically every day with mental

maps and to highlight the importance of asking geographic questions.

Mental mapsare maps of our environment that are stored in our brain

We rely on our mental maps to get from one place to another, to plan our daily activities,

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Spatial Thinking

A B

C

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Spatial Thinking

A B

C

Take a moment to look at each map and compare the maps with the following

questions in mind:

1. What similarities are there on each map?

2. What are some of the differences?

3. Which places or features are illustrated on the map?

4. What assumptions are made in each map?

5. At what scale is the map drawn?

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Geographic Concepts

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Geographic Concepts

The one concept that distinguishes geography from other fields is location, which is central to a GIS.

Location is simply a position on the surface of the earth

a. Locations in nominal or absolute terms ike city names such as New York, Tokyo, or London refer to nominal locations.

b. Location that use some type of reference system to define positions on the earth’s surface. For instance, defining a location on the surface of the earth using latitude and longitude.

c. Location can also be defined in relative terms. For instance, Cairo, Egypt, is north of Johannesburg, South Africa; New Zealand is southeast of Australia

Location

Unlike nominal or absolute locations that define single points, relative locations provide a bit more information and situate one place in relation to another.

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Geographic Concepts

Direction refers to the position of something relative to something else usually along a line.

In order to determine direction, a reference point or benchmark from which direction will be measured needs to be established.

In geography and GISs, there are three more standard benchmarks that are used to define the directions of true north, magnetic north, and grid north

Direction

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Geographic Concepts

Complementing the concepts of location and direction is distance.

Distance refers to the degree or amount of separation between locations and can be measured in nominal or absolute terms with various units.

Absolute distance is measured or calculated using a standard metric. The formula for the distance between two points on a planar (i.e., flat) surface is the following:

Distance

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Geographic Concepts

Where distance suggests a measurable quantity in terms of how far apart locations are situated, space is a more abstract concept that is more commonly described rather than measured.

One kind of space that is of particular relevance to a GIS is topological space.

Simply put, topological space is concerned with the nature of relationships and the connectivity of locations within a given space.

What is importantwithin topological space are

(1) how locations are (or are not) related or connected to each other

(2) the rules that govern such geographic relationships.

Space

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Geographic Concepts

Transportation maps like those discussed previously illustrate how we move through the environments where we live, work, and play. This movement and, in particular,

destination-oriented travel are generally referred to as navigation.

Three following types of geographic knowledge when navigating through space:

a. Landmark knowledge refers to our ability to locate and identify unique points, patterns, or features (e.g., landmarks) in space.

b. Route knowledge permits us to connect and travel between landmarks by moving through space.

c. Survey knowledge enables us to understand where landmarks are in relation to each other and to take shortcuts.

Navigation

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GIS Defined

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GIS Defined

A GIS is a computer based system for management of geographic data.

▶ Geographic data is any data that is geographically referenced i.e.location known.

▶ Information implies that data are organized to yield useful knowledge

▶ System implies GIS is made up of several inter-related and linked components with different functions

From a software perspective, a GIS consists of a special type of computer program capable of storing, editing, processing, and presenting geographic data and information as maps

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GIS Defined

Spatial data refer to the real-world geographic objects of interest, such as streets, buildings,

lakes, and countries, and their respective locations.

From a software perspective, a GIS consists of a special type of computer program capable of storing, editing, processing, and presenting geographic data and information as maps

Attributes, such as a name, number of stories, depth, or population. GIS software keeps track of both the spatial and attribute data and permits us to link the two types of data together to create information and facilitate analysis

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GIS Defined

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GIS Defined

Why way of doing things

Utilize the benefits of information technology - compact storage

- access by many users - better organization of data

Consistency, access formats etc

Faster execution of exististore it in the computer - The “modernng tasks

Newer kinds of operations possible

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GIS Defined

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GIS Defined

Doing newer things … data integration

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GIS Defined

PROCEDURE GIS MANUAL

Display:

300-400 properties

seconds fewminutes

Query: searchfor a

property by address seconds fewminutes

Map Analysis: find

freehold owners seconds fewhours

GIS vs Manual Operations

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GIS Defined

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GIS Defined

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GIS Software

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GIS Software

Several GIS software providers, such as

a. Environmental Systems Research Institute Inc. (http://www.esri.com), which distributes ArcGIS,

b. PitneyBowes (http://www.pbinsight.com), which distributes MapInfo GIS.

c. GRASS (http://grass.itc.it), which is freely distributed and maintained by the open- source community

All GIS software, regardless of vendor, consists of a database management system that is capable of handling and integrating two types of data: spatial data and

attribute data

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Konsep dan Definisi Sistem Informasi Geografis