The Urban Observatory Uses GIS to Seek to Better Understand Cities

Filed in GIS Data by  on July 26, 2013

   Understanding life in the twenty-first century is growing increasingly difficult because of its complexity and interconnectedness. This is especially true for the large, urban areas around the globe. However, the Urban Observatory is hoping that their mapping project will help a wide variety of people better understand cities with their new exhibit and website. Launched on July 8, 2013, the Urban Observatory is a live museum that allows access to a large amount of data about major cities around the world. With this data, users can explore maps of major cities simultaneously. Consequently, these maps can have a large range of uses that include generating a better understand of cities, their inhabitants, and their impacts on the globe.

Created by Richard Wurman and Jon Kamen of @radical.media along with Jack Dangermond of Esri, the Urban Observatory is a large collection of interactive digital maps that anyone can access in order to compare and contrast the organization and structure of urban areas. The purpose of the project is to provide a context in which a deeper meaning of our cities can be derived. The project came about in response to the growing urbanization of our planet. Currently, more than half of the world’s population lives in cities, and the number is predicted to rise to nearly seventy percent by 2050. However, it is difficult to compare and contrast cities to increase our understanding because, so far, maps of these cities have been inconsistent. They are often drawn on different scales and use different symbols.

The Urban Observatory exhibit hopes to change that through the collection of a large amount of GIS data on cities and then displaying it visually on their interactive maps. The observatory allows users to compare and contrast a wide variety of systems and structures including water distribution, power grids, street networks, population density, public transit, open public spaces, among sanitation services among others. The hope is that users, whether it is government officials, business leaders, or ordinary citizens, can determine the impact of urban growth and how that growth is impacting the world. The maps from the Urban Observatory can also be used to view and compare such things as population age, quality of life, health care and cost of living in a dynamic way.

Comparison of population densities between London, New York, and Tokyo.

Comparison of population densities between London, New York, and Tokyo.

The exhibit has been called a live museum with data pulse. The Urban Observatory features maps, images, videos, and data sets for certain cities by taking advantage of such technologies as cloud computing and a large amount of GIS data. The Urban Observatory incorporates two basic elements: the exhibit and the website. The exhibit was unveiled on July 8, 2013 at the Esri International User Conference in San Diego, California. The website can be accessed by anyone with a web browser and it contains many of the functions found at the exhibit. Online users can compare cities side-by-side using the elegant web-based maps, and the application allows people to zoom in on maps with a common scale. The Urban Observatory hopes to add more web applications in the future.

The Urban Observatory exhibit, on the other hand, is a map display on several separate large, flat screen monitors with computers so that users can interact with the city maps. Each one of the monitors is a dynamic display of GIS data: themed maps which show similar types of maps for different cities. The maps include color-coded maps, point location dot maps, planimetric maps, and two-and three-dimensional maps. Many of the maps and data sets are combined in order to create an interactive, vivid experience for users. The maps of the exhibit are organized into the five major categories of work, movement, people, public, and systems. The categories are then further classified into subcategories and themes, either by subject, specific issues, or specific phenomena like daily traffic volume.

The exhibit and website of the Urban Observatory is possible because of the large amount of data collected from urban areas. More than sixteen cities across the globe contributed data for the project. This rich collection of data can not only be visualized with the maps but they can also be set in context in order to help with analysis. This data provides a wealth of information about cities and its residents that can provide a large variety of uses. The maps provide data on work that include employment by industry and occupation, growth, and annual revenues. They can give more information about residential land use, demographic changes, and home and property ownership. The maps can also display the location of public services like hospitals, museums, and law enforcement while providing information on systems like electricity, gas, sanitation, and water.

Ultimately, the purpose of the Urban Observatory is to provide a better understanding of the world’s cities through interactive maps based on all types of GIS data. Plus, the Urban Observatory is encouraging both cities and individuals to contribute to the project by submitting their own data. The hope is that by being able to compare and contrast different aspects of cities, users can examine and analyze every aspect of urban life. The Urban Observatory provides a simpler way to comprehend the complexity of urban life in the twenty-first century.

Link :http://www.gislounge.com/the-urban-observatory-uses-gis-to-seek-to-better-understand-cities/

Five GIS and Mapping Apps for iPhone

Filed in GIS Software and Applications by  on July 11, 2013

   Mobile devices offer productivity benefits for GIS, especially in the field. Cartographers both novice and professionals have taken advantage of this handheld technology to turn it into a useful GIS tool.  The popularity of smartphones such as the iPhone as a data gathering device through apps is growing.

On a global scale land professionals likereal estate agents and city planners have turned to this technology to assist them when they are out on the field. In fact, in the United Kingdom, O2 partnered with three companies to bring innovative solutions to mapping needs. One of those who joined this collaborative project, Telmap, represented by their CEO Oren Nissim said, “There is clearly high consumer demand for mobile mapping and navigation services, demonstrated by the volume of mobile phones released with an embedded GPS. We are very proud to be working with O2 and believe that, together, we can showcase our Navigator product and perfectly position it to take advantage of this growing market as well as enhance the customer experience.”

Photo courtesy of William Hook

Photo courtesy of William Hook

To get you started, we’ve summed up below five highly recommended GIS and mapping applications on the market for your iPhone.

Mobile Geography Tools

1.    WolfGIS is free to download and compatible with iPhone 3GS and up. It is recommended for those who need to perform computations remotely. How is it helpful?

  • It gives you access to detailed information of land along with the GIS functions that you’re looking for.
  • Timber managements, real estate, farming, construction and even government companies will find the user interface (UI) easy to use.  You only need to bring the property up on the app using its Tract Lock feature. It will take out the necessary computations regarding the boundaries of any property.
  • It’s also easy to zipped data through shape files to authorized personnel. With your mobile phone, you can access this cloud storage service so you can save and retrieve the files anytime and anywhere you are.

Wolf-GIS

Wolf-GIS

2.    Maps 3D – GPS Tracks for Bike, Hike, Ski and Outdoor is perfect for extreme athletes presents a completely new view of the world on your iPhone screen.

  • It gives you that precise and important information using its 3D elevation model programmed.
  • Apart from the 3D display, it provides you with an accurate altimeter that displays your elevation. However, you may find some difficulties when trying to sync it with Facebook or Twitter.

Maps3D

Maps3D

3.    GIS Pro is a reliable tool when on the site. It works whether you’re connected to the internet or not.

  • It has cached or downloaded topographic maps, street maps and satellite images stored on the device. You can even use these to draw lines that will serve as your guide when planning your pipe laying or linear projects.
  • Using your mobile device you can get more information by checking the preloaded templates and import or export them to a computer.
  • With its advanced feature, expect a pricey tag on this app at $99.99 per installation.

GIS Pro

GIS Pro

4.    Make your maps come alive using a fast UI and cached maps on ArcGIS.

  • The app takes out the uncertainty of knowing where you are located. It comes with accurate aerial photographs of the site.
  • One thing that you may not appreciate is the off view presented when you are offline. The downloaded maps and other data gathered cannot be retrieved once you turn it off.
  • However, its simple design makes it stable. Therefore users experience fewer crashes compared to the more complicated and unnecessary tools.

ArcGIS

ArcGIS

5.    Integrity GIS is a premiere application for iDevices. It allows you to use the available data anytime, anywhere.

  • It is packed with features that can deliver the results they need. The only thing that you have to do is find the parameter including the layers that you want to present using its search box. Once it presents the results, you can look at the legends on your map to familiarize yourself quickly, especially with the symbols used.
  • These are only five of the best for the iPhone users. We’re certain that there are other applications out there that can provide similar or better results. If you one that you want to recommend, leave a comment below and let us know.

Integrity GIS

Integrity GIS

About the Author:

Nadia Hyeong Nadia Hyeong often looks at mobile phones, social media, music and gadgets and tech. Her love for reto games takes up most of her spare time. You can always find her on Google+ or Twitter.

 Link :http://www.gislounge.com/five-gis-and-map-apps-iphone/

LEARNING MAPPINGCHOOSING THE RIGHT MAP PROJECTION

 

Choosing the Right Map Projection

The USA four ways

Michael Corey’s guide to smashing the earth for fun and profit

Nearly all maps are an attempt to represent our environment (generally Earth) in a two-dimensional format. The act of systematically transposing a 3D to a 2D object is called projection, and it’s a key concept of cartography, the art and science of making maps.

If you’re already familiar with projections and how they work (and often don’t work), jump down to see my process for choosing and using them in news interactives.

In one sense, making a projection is always a futile effort. Why? Because the Earth is not flat: it’s a spheroid. And it’s impossible to completely accurately flatten a spheroid.

Ever since the first cave-cartographer etched the first mammoth-driving directions to the local watering hole on to the wall of a cave, that impossibility has meant making compromises in accuracy. Done poorly, the result is a bad map: at best an ugly one, and at worst one that dramatically misrepresents your data and its context. But once you know a few of the rules, map projections are your key to prioritizing accuracy, readability, and aesthetics that are appropriate to your unique situation.

Will the Real U.S. Please Stand Up? (Mercator and His Discontents)

Let’s start with a real-world example from my work. Which of the four maps above is the real United States?

Well, none of them is accurate, of course. But which looks right to you?

Chances are, you probably are most comfortable with the map at the top left. This is what we’re all used to seeing, not least because it’s the view of the United States you get in Google Maps. In many of the news applications I build, it’s a perfectly good canvas for overlaying points on a map.

But it’s not always the best choice. At the Center for Investigative Reporting, we wanted to show the value of homeland security grants awarded to state and local law enforcement (and even outlying territories) on one map. The challenge was how to get Hawaii and Alaska on the same map. If we wanted to use one of the standard “slippy map” APIs (Google MapsLeafletOpenLayersBing—the kind of map you can drag around)—there are two easy options. The first is to make the default view the lower 48 states, and to not show Alaska and Hawaii unless someone chose to drag the map there. The second option is to show all 50 states at one time, which means every state besides Alaska would be too small for a user to click on or even easily see.

The US with Alaska and Hawaii in Mercator--a bad map

The United States with Alaska and Hawaii in Mercator—a bad map.

Neither of these options were OK with us. Alaska and Hawaii are both states with small populations, true, but they also have a lot of spending per capita, and thus were important to prominently include. So we chose a third approach; we used insets for outlying areas, but there’s still a problem. Which Alaska is the real Alaska?

Alaska in several projections

Alaska in several projections

Which is the real Hawaii?

Hawaii in several projections

Hawaii in several projections

In both of these examples, the first image is based on the same projection as that upper left corner map in my first example, called a Mercator projection. Frankly, for Hawaii, it’s not a terrible choice. But Alaska is a different story. As any Alaskan will tell you, Mercator makes a mess of it.

Yet that terrible Alaska map is probably the version you’re most familiar with.

But why is Mercator likely to be the projection you’re most familiar with? I’ll give you two choices for who to hold responsible. You can blame Uncle Google (who adopted a modified Mercator projection in the first year of Google Maps in 2005) or you can blame Uncle 16th Century Flemish Cartographer Gerardus Mercator.

Mercator’s projection is by far the best-known by laymen, and it’s the most common world map you’ll generally see. Map zealots are down on poor Uncle Mercator, but I’m here to tell you that Mercator is a perfect example of how a given map projection can be hugely helpful or quite misleading depending on the situation.

Mercator world map

Mercator world map

The big beef against Mercator is that it makes Greenlanders feel too good about themselves. It makes areas near to the Earth’s polar regions (Greenland, Alaska and Antarctica, for example) look much larger than they are relative to areas nearer to the equator. This is because Mercator’s balancing act in flattening the globe involved, in effect, stretching the far northern and far southern parts of the world out like silly putty until he had a flat, rectangular map. In the image above, you’ll notice that Greenland appears nearly as large as South America, which is wildly untrue: Greenland has an area of about 836,300 square miles, compared to South America’s 6.9 million square miles. Why did such a crappy map become ubiquitous?

Because the tradeoff for all that distortion in areas where most people don’t want to go (sorry, Greenland) is that it’s a really handy tool for sea navigation by compass—the main reason maps existed for most of the last 500 years.

Think about the maps in the back of the in-flight magazine on an airplane—the ones with all the curvy lines between destinations. This is a good illustration of a phenomenon common to many global projections: a straight-line course between two points on the globe actually appears as a curved line in 2D. And it’s pretty hard to measure distances and angles between curved lines. That’s the brilliance of Mercator’s projection—on a Mercator map, straight courses over the ocean can be accurately drawn as straight lines. Sailors could also easily and accurately calculate the headings they needed by simply measuring the angle between their straight-line courses and Mercator’s straight meridians.

Most of us are not currently navigating on the high seas, however, so shouldn’t we just ditch that dinosaur?

Many cartographers will tell you we should, but when it comes to building interactives for the web, I’m here to argue with them a bit, for two reasons:

  1. You might throw off your users by presenting them with an unfamiliar map of a familiar place, wasting mental energy that should be focused on your data findings.

  2. On a purely practical level, not using Mercator sometimes means you’ll need to use some software that isn’t made for the casual web developer on the street. (Though D3.js does have built-in support for some projections.)

For the times when you genuinely do need to go beyond Mercator, here’s the process I use to make an informed projection choice. Let’s start with the basics.

Pick Your Poison/Choose Your Medicine

The first step in knowing which projection to use is the same as the first step in any visualization: ask yourself what is the most important thing to get across. For example, if you want to show concentric rings of distance around a central point, especially in a limited geographic area (a town or a state), you would use a different projection than if you want to show points across a large nation like the United States. In the first case, you would prioritize a projection that preserved precise angles and directions between objects in a area over a projection that would preserve the areas of similar-sized shapes over a wide geographic area. You can’t really have both.

In most cases, your choice will be significantly informed by the size of the area you care about mapping at any one time.

Mapping Large Areas

When you’re mapping a large area, like the continental United States, the first concern is making sure that the projection you use is going to represent the entire map area reasonably well. Lucky for you, mapping agencies everywhere have often already flagged a good projection for whatever country you’re interested in, so your first stop is to look for that.

Let’s take the United States, for example. Here’s the U.S. National Atlas Equal Area projection:

U.S. National Atlas Equal Area Projection

U.S. National Atlas Equal Area Projection

The major difference you’ll probably notice off the bat between this and Mercator is the border with Canada in the western half of the United States: Instead of being a straight horizontal line, it’s curved. By solving the mathmatical problem of how to flatten the globe differently, Albers does a much better job of showing each state in proportion to all the others than something like Mercator.

So problem solved, right? Why don’t we just all use Albers? Because the U.S. National Atlast Equal Area projection is heavily optimized for the characteristics of the United States: wider east to west than north to south. South America, for example, is the opposite and requires different projections.

If you have looked around and still haven’t found a good answer, you can also try out this amazing tool to help choose a projection.

Mapping Small Areas

When you’re mapping a smaller area, like a city, you don’t have to worry as much about distortion as you get farther away from the center. But since you’re much more zoomed in, precision becomes a primary concern.

If you measure the distance between a city in Colorado and a city in California and you’re off by a half mile it’s no big deal. But if you’re giving someone walking directions to a restaurant near her office, being a half mile off is pretty unacceptable.

For a regional map—a few counties, or even many smaller states—a UTM (Universal Transverse Mercator, not the same as a Mercator, confusingly) projection might be a good choice. One of the biggest advantages of a UTM is that measuring distances between two points is a snap. Measuring distances between points in more familiar latitude and longitude degrees requires some pretty complex math, though modern software tools often have distance calculations built in. But in UTM, there are no degrees—the map units are measured in meters. That makes for high accuracy, easy math and easy conversions.

UTM zones

UTM zones

The trade-off is that this trick only works over relatively small areas. UTM keeps distortion down by dividing the earth into 60 zones, each of which is about 300-475 miles wide east-to-west, depending on what latitude you’re at. Inside that zone, and usually into the next zone east or west, measurements are quite accurate. But that accuracy fades the farther away from the origin you get. That means you need to know which zone your map area is in, and it makes UTM a poor choice for national or world maps.

How to Project Your Map

OK, you know which projection you want to use, but how to do you get it into that projection?

There are numerous options, depending on what technology you’re using. The common currency of spatial data is the ESRI shapefile, so we’ll stick to that for this article. (If you’re database-inclined, I’d definitely recommend looking into PostGIS, but that’s another article.)

There are a few steps to getting your map projected correctly:

  1. Determine what projection the map is currently in
  2. Tell your software of choice what the new projection will be
  3. Convert!
  4. Save your new map with a useful filename so you can tell what you did later

Determine what projection your source map is in

This will vary with what kind of spatial file you’re using, but we’re assuming shapefile.

A shapefile actually is a folder containing several files. There are sometimes more, but shapefiles almost always have a .shp, a .dbf and a .prj file. As you might have guessed, the projection information is in the .prj file.

Here’s a .prj file from a California shapefile:

GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],
PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]]

Well, that’s helpful, right? Thankfully, you’re not on your own. Spatial software like Quantum GIS or ArcGIS will figure it out for you.

In Quantum GIS, for example, in Layer Properties > General > Specify, you can see that the program has identified the projection (using the .prj file) as EPSG 4326. That EPSG code is an example of anSRID (Spatial Reference System Identifier) — a unique, shorthand code that identifies the projection. And once you have an SRID, you’re in business. Nearly every piece of spatial software will project whatever you want into whatever project you want, as long as you know the SRID you have and the SRID you want.

Quantum GIS SRS selector

Incidentally, EPSG 4326, also called WGS 84, is a very common spatial reference system, and many of the shapefiles or other spatial data you ever download will be in SRID 4326.

Technically, WGS 84 is not even a projection, and this is an important distinction. SRID 4326/WGS84 is an example of an un-projected datum. A datum is a mathematical model of the earth as a spheroid, and there are actually quite a few different ones in use. Every projection has a datum under the hood, but a spatial reference system is only “projected” when it has been mathematically translated to a 2D surface. Since SRID 4326 coordinates are still in degrees representing points on a spheroid, they’re not projected. The U.S. Census Bureau uses another un-projected datum, NAD 83, when it releases most (if not all) of its shapefiles.

Unfortunately, in many cases, the spatial data you receive from a government agency or other source will not include projection information. This is annoying—never do this to someone when you become a powerful government GIS official—and it can be a difficult problem to solve.

Do not guess! Even if you find that your data seems pretty close to a known projection, different projections use completely different mathematical models of the earth’s spheroid, which can make your points appear a long distance from their actual locations.

First, check the agency’s website to see if they have a projection that all their spatial data is released in. As long as you got the data directly from them, you’re OK in this case. If you don’t find that clearly stated, contact the agency that created the data, and insist on speaking with a GIS person—no one else will have any idea what you’re talking about.

Find the SRID of your target projection

There are a few ways you might find the SRID of the new projection you want. If you found the projection on a government mapping site, the site might list the EPSG ID of the projection.

If you’re not lucky enough to have an SRID in hand, your next best friend is a search engine andspatialreference.org. For example, if you need to look up the Google Maps Mercator projection, just search “Google maps projection EPSG” in Google or Yahoo. You’ll actually get a number of different answers, but EPSG:3857 comes up the most. Of course we’re not just going to take the search engine’s word for it. Now go to spatialreference.org and search EPSG:3857 to see if that makes sense.

And at http://spatialreference.org/ref/sr-org/7483/, we get this description:

EPSG:3857 — WGS84 Web Mercator (Auxiliary Sphere)

Projection used in many popular web mapping applications (Google/Bing/OpenStreetMap/etc). Sometimes known as EPSG:900913.

Ding! Ding! Ding! We have a winner.

You’ll notice that there are a few numbers here: EPSG:3857, 900913 (hint: it spells “Google,” and isn’t really an official SRID), and SR-ORG:7483. Always go with the EPSG code when available—it’s the most widely used system by far.

If there’s no ID, the agency might list a projection name like “California State Plane system.” TheU.S. state plane coordinate system divides regions of each state into zones, which each use their own, slightly different projection. This makes things a bit complicated if your map covers a large area, but the advantage is a high degree of accuracy for local maps (like a city or metro area).

In a case like this, you’ll need to figure out which zone your map covers. Let’s take another California example. Los Angeles county is in Zone 5. So if you’re mapping LA, a good choice would be California State Plane Zone 5. If we search “California State Plane Zone 5 EPSG” in Google, the top result includes a list of projections:

SPCS ID Datum and Grid Name EPSG ID 203 NAD83 / Arizona West 26950 301 NAD83/ Arkansas North 26951 302 NAD83 / Arkansas South 26952 401 NAD83 / California zone 1 26941 402 NAD83 / California zone 2 26942 403 NAD83 / California zone 3 26943 404 NAD83/ California zone 4 26944 405 NAD83 / California zone 5 26945 406 NAD83 / California zone 6 26946 501 NAD83 / Colorado North 26953 502 NAD83 / Colorado Central 26954 503NAD83 / Colorado South 26955

Looks like EPSG:26945 is our winner. And spatialreference.org agrees.

Convert the shapefile to the new projection

In Quantum GIS, this is as easy as right-clicking the layer you want to project, choose Save As, then choose Browse next to CRS (that stands for coordinate reference system), and search by EPSG.

Save your new map with a useful filename

This seems like a minor point, but I have maybe 10 identical shapefiles of the California state border in different projections. Do yourself a favor and include the SRID in the filename (e.g. california_border_4326.shp).

Insets

Let’s get back to the police grants map we started talking about at the top. As I said earlier, we decided that insets for Alaska and Hawaii were the way to go. But that doesn’t mean we should use the same projection for the insets as we did for the main map—in fact, using the same one in a case where you’re using insets is often a pretty bad choice.

Check out what happens to Hawaii when we put it in EPSG:2163, AKA U.S. National Atlas Equal Area Projection, the projection we used for the main map.

Hawaii tipping over

Hawaii tipping over

The point is: find the best projection for each individual inset.

Where to Go from Here

If you can believe it we’ve barely scratched the surface. I’ve left out a lot about the theories and terminologies behind each projection system in the hope that you’ll get your feet wet, get hooked, and come back for more. Start here: Map Projections: From Spherical Earth to Flat Map Projections presentation by Nathaniel Kelso (Apple, formerly Stamen Design) (Slides 47-55) D3 and the Power of Projections

So send your geometry teacher a thank you card, because it’s about to get nerdy as you start practicing the best ways to slice and dice the planet.

Map data sources: Natural EarthU.S. National AtlasU.S. Census BureauNational Geospatial-Intelligence Agency

 

COMPARISON OF FREE SOFTWARE DESKTOP GIS

 

WRITTEN BY GIMI AAUCTU ON DECEMBER 16, 2013. POSTED IN ARTICLES

The Research Group in Information Management (GIMI) of the Pedagogical and Technological University of Colombia , made ​​a comparison on free GIS software, based on quality metrics defined in the standard ISO 9126-3. The results were presented at the 5th Conference of Latin American and Caribbean gvSIG , held in Buenos Aires in October 2013.

Conducting comparative born of the need to select a set of free tools that would allow the creation of a platform for managing the Land Use Plan (POT) of the different municipalities in Colombia.

SIG-OT Colombia

The tools have been tested gvSIG , GRASS , Kosmo , OpenJump , Saga , uDig and Quantum . The evaluation parameters, falls under the ISO 9126 standard – 3, were:

  • Basic functionality: for the development of GIS applied to the POT is essential to have a tool that facilitates the management of layers and their attributes.
  • Spatial analysis is considered important, because proper management for the POT analysis of geographical data for decision-making is required.
  • Ability vector: vector data processing is the most common observed in different GIS consulted therefore considered indispensable.
  • Raster Capacity: data processing raster GIS for Land Management Plans are not considered necessities, however, is necessary to evaluate this parameter.
  • Interoperability: is of great importance because many GIS systems are composed of various (databases, map servers) so it must have characteristics that allow their interaction. Yield capacity in response times and streamline back GIS creation processes.
  • Generating maps: tools and / or functions to create colorful maps and generate reports are important because they facilitate the publication of results.
  • Documentation and support: documentation and tool support are considered complementary because they are not fundamental to the development of GIS.

According to the evaluation of the parameters specified above and a detailed study of the various components and functions of the tools, supported by 5 theses developed by researchers GIMI, presented below the score for each of the tools assessed:

 
gvSIG
GRASS
Kosmo
OpenJump
Saga
uDIG
Quantum
Basic Functionality
4.76
5.00
4.22
4.31
3.50
4.72
4.60
Spatial Analysis
5.00
5.00
2.06
3.86
4.82
2.86
3.89
Vectorial capacity
4.75
4.80
3.45
4.50
3.00
4.80
5.00
Capacity raster
4.79
5.00
1.00
3.00
4.25
0.00
0.00
Interoperability
5.00
4.84
3.45
2.95
0.86
4.49
3.94
Performance
5.00
5.00
4.08
3.28
3.18
4.40
4.00
Map generation
4.94
4.71
3.36
2.97
1.88
3.02
3.73
Documentation and Support
5.00
5.00
5.00
5.00
5.00
5.00
5.00

From the table above and taking into account the number of parameters, factors, indices and indicators considered, it can be concluded that performing grading tools, gvSIG has better performance in terms of free GIS tools:

Tool
Score
gvSIG
4.90
GRASS
4.88
Kosmo
3.47
OpenJump
3.70
Saga
3.01
uDIG
3.96
Quantum
4.01

For the development of any suite, or application, you must use the best tools to develop a quality system that meets all the metrics proposed by different international institutes such as ISO, based on the results of the comparison, suggests using the gvSIG tool for the development of Geographic Information Systems focused on the management of Land Management Plans, particularly in Colombia.  
should be noted that the results of the comparison depend on the application that will be developed, and thus functionalities that this requires.

This text is a short summary of the article written by Juan Sebastián González Sanabria , assistant professor at the Pedagogical and Technological University of Colombia (Tunja, Boyacá – Colombia) and  Gustavo Caceres Castellanos , a professor associated Pedagogical and Technological University of Colombia (Tunja, Boyacá – Colombia). 

Watch Amtrak’s Trains Move Along Their Routes in Real Time

Watch Amtrak’s Trains Move Along Their Routes in Real Time

Watch Amtrak's Trains Move Along Their Routes in Real Time
Reuters

This week Amtrak released “Track a Train” — an interactive, Google-powered, real-time-ish status map of its 300-plus daily trips. America’s passenger rail provider says it created the feature because checking train status is the second most-popular action on its website, after buying tickets. Now travelers and train enthusiasts alike can see how slow fast a particular Amtrak train is moving at any given time.

Requisite snark aside, the service looks both polished and useful. (You can find it in the lower-left corner of Amtrak’s main site.) The base map gives a national overview of Amtrak’s service at the moment. Active trains are indicated by a blue arrow pointing in the direction they’re traveling. Stations are shown as smaller white dots. A purple circle enclosing a number shows how many trains are in high-traffic areas and lets users zoom in with one click.

A status window for each individual train gives the train number, direction, origin, final destination, and speed. There’s also a status flag: green indicates on-time trains; amber, late trains. One check this morning found a gray flag to indicate a route with a service disruption. The most handy feature is a scrollable history that gives the local times every arrival a train has made (or will make) on that route.

Yes, that is an Acela moving at 134 miles per hour — just a glimpse of what Amtrak trains are capable of doing when proper track configuration allows.

There are plenty of basic Google Maps features, too, including a traditional zoom feature, a search window that auto-fills for stations or route names, and a satellite viewing option. (You can’t zoom in close enough to see the actual track, however, perhaps for security reasons.) There’s even a nifty national “reset” button that takes you take back to the base screen that the original Google Maps would be wise to steal.

So there it is: not groundbreaking, of course, but functional, clean, and customer friendly. Amtrak’s management is always being criticized for its shortcomings. That’s the way it should be for a taxpayer-subsidized service, and indeed sometimes the flaws are glaring (as in the case of its inefficient food service). But Amtrak’s innovations deserve some credit, too.

At times it’s even been ahead of the technological curve. Amtrak has taken the lead implementing positive train control safety upgrades, and it was using mobile ticketing well before transit agencies started doing the same in major U.S. cities (if anything, it made the shift too quickly, confusing some older customers). Its WiFi service is a mess, of course, but private-sector in-flight Internet providers haven’t exactly perfected that system, either.

Anyone interested in learning more about the “Track a Train” system might turn to a Q&A that Amtrak conducted (if you will) with Google Maps product manager Dylan Lorimer. It’s mostly vanilla stuff, but one of Lorimer’s answers is entertaining:

As you know, our trains go to a lot of places. If you could go to any of our 500 destinations, where would you go?

Remember that train robbery scene from Breaking Bad (season 5, episode 5), where they steal the supply of methylamine? Maybe there? Just kidding. For sure, I’d take the Empire Builder through Glacier National Park! I can’t wait to do that one day.

Two things. One, he’s so obviously not just kidding. Two, let’s just hope he doesn’t hop thatEmpire Builder during a government shutdown. If he does, though, at least he’ll be able to see whether or not he’ll arrive at that closed park on-time.

Keywords: Google MapsAmtrak

Eric Jaffe is a contributing writer to The Atlantic Cities and the author of The King’s Best Highway: The Lost History of the Boston Post Road, the Route That Made America. He lives in New York. All posts »

Epic Flooding in Calgary, By the Numbers

Officials and residents are beginning to clean up Calgary, where the worst flooding in Alberta’s history forced 75,000 people from their homes on Friday.

A torrent of water from the Bow and Elbow Rivers, which nearly overran the city’s bridges, receded slowly over the weekend, leaving streets full of silt, waterlogged cars, and whole neighborhoods without electricity or working sewers. For most residents, the mandatory evacuation order was lifted on Sunday.

The flooding, Premier Alison Redford said, was “like nothing that we’ve ever seen before in Alberta. We will live with this forever.” Schools will be closed until at least Thursday, and the city has asked residents to steer clear of downtown for the foreseeable future.

Today, as residents confront the damage to their homes in the Calgary area, the surging waters have moved downstream toward Medicine Hat, a city 200 miles to the southeast, which is bracing for a record flow in the South Saskatchewan River today.

So just how bad has the flooding in Alberta been? These stats should help put this historic event in context:

  • 1,097,000: the population of Calgary, which is Canada’s third-largest city and fifth-largest metro area. It’s bigger than all but nine U.S. cities.
  • 75,000: the number of people who were under a mandatory evacuation order in the city beginning on Friday.
  • 4: the number of people who have died so far in Alberta as a result of the floods. One woman, age 88, was found dead in Calgary.
  • 12: number of prisoners relocated as a result of rising water
  • 11: number of bridges that remained closed in Calgary on Monday morning.
  • 1,700: the number of cubic meters per second flowing in the Bow River in Calgary, the city’s highest recorded flow since 1897.
  • 3: the number of times greater the peak levels of the Bow and Elbow Rivers were this weekend than in 2005, when floods caused $275 million in damage.
  • 6-7: number of times the normal water volume flowing through the Bow River on Friday.
  • 10: rows of the Saddledome, Calgary’s hockey arena, that were submerged by flood waters.

Below, via Reuters, scenes from around the city over the weekend:


The Bow River over flows its banks into the downtown core and residential areas in Calgary, Alberta June 22, 2013. The heaviest floods in decades shut down the Canadian oil capital of Calgary on Friday, forcing the evacuations of tens of thousands of residents and shutting the Alberta city’s downtown core. Some 1,300 troops were deployed to help with rescues and the mandatory evacuations that forced 100,000 people from their homes in Calgary and thousands more in the small towns surrounding the city. (REUTERS/Andy Clark)


The grounds of the Calgary Stampede remain under water after they were flooded in Calgary, Alberta June 22, 2013. The flooding Bow River shut down all of the centre of Calgary, Canada’s oil capital, and will remind closed until mid week. The flood forced tens of thousands of residents to leave their soggy homes. Heavy rain also closed roads and brought down bridges elsewhere in the province of Alberta, and there are reports of up to 4 deaths from the flooding. Many communities across southern Alberta are on mandatory evacuation orders because of severe flooding. (REUTERS/Melissa Renwick)


Heavy equipment begin repairs after a span of a railway bridge was swept away by flood waters on the Sheep River in Okotoks, Alberta, south of Calgary June 23, 2013. Power outages in the Canadian oil capital of Calgary could last for weeks or even months, city authorities said on Sunday, as record breaking flood waters moved downstream to threaten smaller communities in southeastern Alberta. (REUTERS/Andy Clark)


Two men carrying a canoe walk on a muddy street after the community of Bowness was flooded by the Bow River in Calgary, Alberta, June 23, 2013. (REUTERS/Melissa Renwick)


Muddy photographs dry on a bulletin board after it was salvaged from a flooded house in the community of Bowness in Calgary, Alberta, June 23, 2013. Power outages in the Canadian oil capital of Calgary could last for weeks or even months, city authorities said on Sunday, as record breaking flood waters moved downstream to threaten smaller communities in southeastern Alberta. (REUTERS/Melissa Renwick)


A pair of ducks swim on a flooded street in Calgary, Alberta June 23, 2013. An estimated 65,000 people have been allowed to return to their homes as flood waters recede. (REUTERS/Andy Clark)


Gophers line the city sidewalks after their homes were flooded in the East Village area of Calgary, Alberta June 22, 2013. The flooding Bow River shut down all of the centre of Calgary, Canada’s oil capital, and will remind closed until mid week The flood forced tens of thousands of residents to leave their soggy homes. Heavy rain also closed roads and brought down bridges elsewhere in the province of Alberta, and there are reports of up to 4 deaths from the flooding. Many communities across southern Alberta are on mandatory evacuation orders because of severe flooding. (REUTERS/Todd Korol)


The Bow River overflows its banks into a residential area in Calgary, Alberta June 22, 2013. The heaviest floods in decades shut down the Canadian oil capital of Calgary on Friday, forcing the evacuations of tens of thousands of residents and shutting the Alberta city’s downtown core. Some 1,300 troops were deployed to help with rescues and the mandatory evacuations that forced 100,000 people from their homes in Calgary and thousands more in the small towns surrounding the city. (REUTERS/Andy Clark)


A house is surrounded by water after the Bow River overflowed its banks nearby into residential areas of Calgary, Alberta June 22, 2013. (REUTERS/Andy Clark)


A woman takes a photo of the flooded East Village in Calgary, Alberta June 22, 2013. Southern Alberta braced for more disruption on Saturday from floods that have killed at least two people, forced about 100,000 people from their homes and blacked out the center of Canada’s oil capital, Calgary. Communities to the south and east of Calgary were put on high alert as the flood waters moved across the region. But with rainfall easing up, authorities were hopeful that the worst might now be over. (REUTERS/Todd Korol)

Keywords: CalgaryWeatherRainFloodsFlooding

Henry Grabar is a freelance writer and a former fellow at The Atlantic Cities. He lives in New York. All posts »

New Satellite Maps Reveal the Staggering Extent of Europe’s Flooding

How bad is the historic flooding that’s turning Europe into a certain terrific Kevin Costner flick? Take a look at these images captured by the Landsat 8 satellite that NASA featured todayalong with a nifty, sliding comparison tool. The first is from May 6 and shows the farmland around the city of Wittenberg, population 50,000:

What a nice, docile-looking river. It’s the Elbe – a major European waterway that meanders through the lowlands of Germany and the Czech Republic. See if you recognize the same river in this shot from June 7:

The blue rivulet is gone, replaced with a massive watery boa the color of milky coffee. When this photo was taken, the Elbe was swollen to a height of  22 feet, prompting workers in Wittenberg to make a defensive perimeter of sandbags around town. Yesterday, German police had to shut down the city center in anticipation of the Elbe soon cresting.

This monumental dousing has drawn comparisons to the terrible European flood of 2002, supposedly a “once in a century” event. But meteorologist Jeff Masters has noted that in some places in Germany this year’s flooding is worse – the Danube River rose to its highest recorded level since 1501, and the Saale also broke a record that was set 400 years ago.

Zooming in, here’s Wittenberg again in May:

And the same area last week:

Nutso. The flooding, caused partly by an unusual weather pattern that’s dumped torrents of rain over Europe, has smashed down dykes and reportedly killed at least 23 people. The costs of cleaning up after this mess is likely to be in the billions of euros.

Images courtesy of NASA / U.S. Geological Survey

John Metcalfe is a staff writer at The Atlantic Cities. All posts »