WEB GIS

INTRODUCTION GEOGRAPHIC INFORMATION SYSTEM THE INTERNET AND THE WEB WEB GIS CONCEPT WEB GIS ORIGIN AND EVOLUTION WHY WEB GIS?

WEB GIS ARCHITECTURE WEB GIS MAPPING TECHNOLOGIES WEB GIS CHARACTERISTICS WEB GIS SOFTWARE AVAILABLE WEB GIS APPLICATIONS

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The increasing popularity of the Internet has led to the development of Web applications, known as Web GIS.

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Web GIS, as the combination of the Web and geographic information system (s), has

grown into a rapidly developing discipline since its inception in 1993. •

A Web GIS system offers different GIS services for analysis and visualization of geographical information on the Web.

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By using Web GIS applications, users may view, query, analyze, and download spatial information from anywhere at any time.

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Web GIS applications evolved from the delivery of static maps conveyed in raster formats (e.g., JPEG, GIF, PNG) to an actual stage in which map is generated

dynamically from a database and transmitted in the vector format. •

The Web has unlocked the power of GIS, from offices to laboratories. It has put GIS in the homes of millions and in the hands of billions.

• Everything that happens, happens somewhere. •

Knowing “what” is “where” and “why” it is there, can be critically important for making decisions in personal life as well as in an organization.

• GIS is the technology as well as the science for handling the “where” type of questions and for making intelligent decisions based on space and location. • GIS is a system of hardware, software, and procedures that capture, store, edit, manipulate, manage, analyze, share, and display geo-referenced data. • GIS technology has been around since before the Internet and the Web.

• GIS allows a user to see locations, events, features, and environmental changes with unprecedented clarity, showing layer upon layer of information such as environmental trends, soil stability, etc.

• The Internet didn’t gain popularity until the 1990s. Before then, the Internet was complex to use, • In 1990, Tim Berners-Lee, dramatically changed the way the Internet was used. • He invented HTTP, HTML, and the URL.

• He developed the world’s first Web server and a Web browser, naming his invention as the “World Wide Web WWW”, • The terms Internet and the World Wide Web are synonymous in the minds of many, but they have different meaning.

• The Internet is a massive network of networks that connects millions of computers (via protocols such as HTTP, SMTP, FTP, etc.) worldwide.

• The World Wide Web is a system of interlinked hypertext documents and programs that can be accessed via the Internet primarily by using HTTP. • So it is that the Web is the “face” of the Internet.

• Web GIS is a type of distributed information system. • Web GIS is any GIS that uses Web technology to communicate between components. • Web GIS are a special case of Web applications, meant to deal with complex geographic data and share them across several users for different business goals. • Web GIS, this kind of systems require special focus on spatial data which may be acquired from different sources and stored in different formats.

• The fusion of the Internet and the Web and traditional disciplines has created many new ones, and Web GIS is one of these disciplines. • Web GIS has evolved rapidly since 1993, especially in the so-called “Web 2.0” era. • In 1993, the Xerox Corporation developed a Web-based map viewer, marking the origin of Web GIS. The Web site provided simple map zoom capabilities, layer selection, and map projection conversion functions.

1962 CGIS Roger Tomlinson Father of GIS

1969 Internet

1990 Tim Berners-Lee Father of the Web HTTP, HTML, URL

1993 Web GIS Xerox PARC Viewer

• GIS Desktop tools and applications have enabled users to view and analyze spatial data in its proper format. • With the evolution of GIS, the sophistication of these analytical tools has increased tremendously, thereby increasing the cost and time required to understand and use these tools efficiently. • Additionally, most end-users today are interested in the interpretation of the final results in its final format or through visual representation.

Conventional GIS GIS Data

GIS Data

Alfiya Zhaparkulova

Akylbek Chymyrov

GIS Data

Nagima Alimbekova

GIS Data GIS Data GIS Data

Kamilia Mukhanova

GIS Data

Tatygul Urmambetova

Kydyr Nazarkulov

Adilet Bekturov

GIS Data GIS Data

Erik Zheentaev

Nurbek Chymbyldaev

Why Web GIS?

• The emergence of Web GIS is unlocking the power of GIS to a wider audience. • Web GIS provides GIS users: – easy access to geographic information data, – spatial information and GIS modeling and processing tools. – It provides an open and distributed architecture for disseminating geospatial data and web processing tools on the Internet.

• The Web has made GIS not only more accessible to people in their offices, homes, and on the go, but also more flexible through Web-based APIs.

Web GIS

Alfiya Zhaparkulova

Nagima Alimbekova

Akylbek Chymyrov

Kydyr Nazarkulov

GIS Data Kamilia Mukhanova

Adilet Bekturov

Tatygul Urmambetova Nurbek Chymbyldaev

• The simplest architecture of Web GIS is a two – tier system that involves a server and a client, where the server is a Web application server, and the client is a Web browser, a desktop application, or a mobile application.

• a more efficient architecture is a 3-tier architecture which allows a flexible separation of the domain logic (Application Tier) from the data source (Database Tier) and the data presentation logics (Presentation Tier).

• In such circumstances, if any part of the application needs to be changed, other parts do not get affected by that change, and the web application remains scalable to changes in different development environments • The architecture is composed of three layers: the client layer (presentation), the application logic layer and the database layer, as illustrated in figure below.

• A multi-tier architecture follows a Client/ server architecture. • In Web GIS, – the client or the application sends an HTTP request to the web server. – The web server forwards the request to the application server. – The application server then responds to the request by forwarding it to the appropriate map server and manages the load amongst the map servers. – The Map server then further synthesizes the request and performs the appropriate GIS function while retrieving the data from the data server.

• An important part of every Web GIS application is its mapping or visualization technology, which makes it possible to show data in the form of maps. • There are three ways in which visualization functionality is implemented:– Static map renderers, – Slippy maps, and – Flash mapping.

• Web mapping deals at least with two basic problems: map generation, and map transmission.

• STATIC MAP RENDERERS • They render maps in the form of images in raster formats (e.g., JPEG, GIF, PNG). and then send the image back to the user who can view it using a web or desktop application.

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Static map renderers do not allow any user interaction with the maps.

• They do not allow users to pan or zoom in, out or around the map.

• SLIPPY (TILE-BASED) MAPS • This technique works by dividing the map into a discrete number of zoom levels, so that each zoom level has an identical number of tiles. • Instead of accessing the whole map at once, a tile-based client builds the map by accessing individual tiles and then assembling them to form a map. • Google Maps, Microsoft Virtual Earth, Yahoo Maps, Mapnik, Open Layers, and ArcGiS are based on tile based or slippy maps. • It is an alternative to static maps because they are dynamic and faster to load. • The coordinates identified when a user clicks to view the finest level of detail acts as the origin of the tiling divisions and all the tiles are numbered.

• FLASH MAPPING • Flash maps are based on vector graphics.

• Vector graphics move applications beyond simply viewing maps and into an interactive, rich client experience that uses features within map data. • Adobe® Flash (SWF) and Scalable Vector Graphics (SVG) are the two most common vector map formats. • Vector graphics look good whether zoomed in or zoomed out, and they allow for dynamic resizing without having to request a new image from the map server.

• The advantages of Web GIS over traditional desktop GIS, including the following: •

A global reach: a user can access Web GIS applications from their home computer

or cell phone. •

A large number of users: desktop GIS is used by only one user at a time, while a Web GIS can be used by dozens or hundreds of users simultaneously.

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Better cross – platform capability: the majority of clients of Web GIS are Web browsers.

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Low cost as averaged by the number of users: Generally, you do not need to buy software or pay to use Web GIS.

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Easy to use for end users: desktop GIS is intended for professional users. Web GIS is intended for a broad audience, “if I don’t know how to use your site, it’s your fault”.

• ESRI: ArcIMS – A Web GIS viewer (also known as an Internet map server) is a program to view maps on the Internet as generated by geographic information system (GIS) software.

• AutoDesk: MapGuide – Is a web-based map-making platform that enables users to quickly develop and deploy web mapping applications and geospatial web services.

• Intergraph: GeoMedia WebMap • UMN: MapServer • MapInfo: MapXtreme • Caris: Spatial Fusion • Bentley: ModelServer Publisher

• Web GIS System for Real-Time Field Data Collection Using a Personal Mobile Phone • Traditional field data collection (i.e. pen-and-paper based) is a time consuming. • For example, we need to prepare basemaps, collect an ancillary dataset, and other paperwork. • This is not practical to use in real-time disaster information collection, which occurs in unpredictable places and requires a quick emergency response. • We need to find an alternate way to collect field data in a handy and timely manner at low cost, such as using a personal mobile phone. • Figure below shows the detailed system design of field data collection using a personal mobile phone.

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• Basically this system can be divided into three sections: • Field Data Collection: includes a GPS embedded mobile phone or GPS plus mobile phone. • Automation Process: All functions of receiving mails, data injection and format conversion processes will be performed automatically • End Users: interfaces with the Web-GIS. Users can download up-to-date survey data in an ESRI Shape file format through their Web-GIS browser. User can also perform basic GIS functions such as distance measurement, finding the closet facilities within user defined search distances, labeling of attribute names, linking between survey records and maps, and viewing the attached image files through a Web-GIS browser as illustrated in Figure below.

• Web GIS Applications in Transportation

• Real-time advanced traffic information system. • Real-time traffic congestion management. • Automatic trip planning.

• Transportation and land use integration. • Public participation in transportation planning process.

• Zillow for Housing Information • Zillow provides information on: – sales price, – asking price, and – characteristics of homes in a given location.

• This application interfaces with other online tools such as Walkscore and Google Streetview to provide a more comprehensive picture of homes’ value and amenities.

• Walk Score • This application calculates a walkability score for a given location based on the number of destinations (e.g., restaurants, parks, grocery stores) within walking distance. • Closer destinations are weighted more heavily than further destinations. • Other applications on the site include a tool to analyze your commute and a tool that calculates your housing and transportation costs.