Monday, May 28, 2012

Satellite images help doctors count people from space

For the first time, the population of an entire city has been estimated from space through a pioneering project to speed up medical and disaster relief efforts. By analysing satellite images of disaster zones and famine, war or disease-hit areas where census data is unreliable, or cities unreachable, researchers hope to make rapid and more accurate estimates of how many people might need help.

"Population numbers are crucial to everything we do," says Ruby Siddiqui of the global charity, Medicins Sans Frontières, a collaborator in the project to evaluate the satellite counting technique. "We need to plan the size, scale and mode of interventions, and without population numbers we can't do this," she says.

At present, groups like MSF rely on the "quadrat" method to estimate population size. Surveyors visit a sample of individual households to find out how many people live in each type of dwelling. From this, they estimate the population of the entire town or refugee camp. But the method is slow, it demands teams of up to a dozen samplers, and requires careful data analysis afterwards. Also, such operations can be hazardous or impossible to carry out in conflict zones such as Syria.

To overcome some of these obstacles, Chris Grundy of the London School of Hygiene and Tropical Medicine has led a project to estimate the population of Am Timan in Chad using satellite images.

The entire population is to receive meningitis vaccinations, and MSF wants to know how many doses to order.

Preliminary results presented last week in London at the annual research meeting of MSF revealed that the satellite method matched the quadrat method for accuracy. Also, it took about half the time to deliver an answer, although Grundy says that with refinement it has the potential to be much faster.

Surveyors, including Siddiqui, still had to visit households in Am Timan to estimate how many people typically lived in each kind of building, but they could then make a city-wide estimate by counting the total number of each type of dwelling in the satellite image, either through a computer automated analysis or by manual counting.

The quadrat method, which required sampling visits to 1160 dwellings, gave a population of 49,722. The satellite technique, which required sampling visits to only 348 dwellings, gave estimates of 46,625 for the manual and 45,400 for the automated method.

"These results are very good, and there's no doubt they'd be good enough for what MSF wants to do," says Grundy. But the team hopes to make it faster still, potentially eliminating the need to sample dwellings first.

Grundy's team is also evaluating the counting method in 11 refugee camps around the world, including in earthquake-hit Haiti. "We now know it works, that MSF can do it. The next step is to simplify it," he says.

Written By:- Andy Coghlan

Tuesday, May 8, 2012

GIS Cloud

Cloud computing is rapidly emerging as a technology almost every industry that provides or consumes software, hardware, and infrastructure can leverage. The technology and architecture that cloud service and deployment models offer are a key area of research and development for GIS technology.

What Is Cloud Computing? 

Although there are several variations on the definition of cloud computing, some basic tenets characterize this coming revolution. Cloud computing furnishes technological capabilities—commonly maintained off premises—that are delivered on demand as services via the Internet. Cloud GIS offerings can range from data storage to end-user Web applications to other focused computing services. Esri considers cloud computing and technology important in the development and vision of the ArcGIS platform.


Public versus Private Cloud

There are several types of cloud computing deployment scenarios.


The National Institute of Standards and Technology (NIST) is emerging as the preferred provider of the de facto definition of cloud computing and the distribution models, seen here with some Esri examples.

Public Cloud

The public cloud is the most commonly referenced regarding the topic of cloud computing, where the infrastructure and applications are owned by the organization selling cloud services.

Private Cloud

Since many traditional vendors and users are not quite ready to jump into public cloud computing or are restricted from doing so, the cloud service tiers are replicated within a private cloud environment, behind the firewall, and maintained within the parameters of the host organization.

Hybrid Cloud

Many believe that the sweet spot for cost optimization in an organization will rely on a delicate balance of public, or community, and private clouds. However, since this hybrid cloud solution is commonly bound together by proprietary technology, it will only be embraced by enterprise computing in the future as standards are developed.

Cloud Service Models

Three core options compose the service model within the cloud computing environment.

Each service category can be leveraged independently or consumed in combination with other service tiers.

Software as a Service (SaaS)

SaaS comprises end-user applications delivered as a service rather than as traditional, on-premises software. The most commonly referenced example of SaaS is Salesforce.com, which provides a customer relationship management (CRM) system accessible via the Internet.

Platform as a Service (PaaS)

PaaS provides an application platform, or middleware, as a service on which developers can build and deploy custom applications. Common solutions provided in this tier range from APIs and tools to database and business process management systems to security integration, allowing developers to build applications and run them on the infrastructure that the cloud vendor owns and maintains. Microsoft's Windows Azure platform services are often referenced as PaaS solutions at this middleware tier.

Infrastructure as a Service (IaaS)

IaaS primarily encompasses the hardware and technology for computing power, storage, operating systems, or other infrastructure, delivered as off-premise, on-demand services rather than as dedicated, on-site resources such as the Amazon Elastic Compute Cloud (Amazon EC2).

Source:- ESRI Technology Topics

3D Motion Data Capturing Device for GIS

3D ArcGIS Explorer Desktop globe
The Microsoft Xbox 360 Kinect is one of most powerful consumer-oriented “Natural User Interface” devices available today. Its near-infrared camera produces 3D motion data of anything in front of the it and coupled with a standard webcam and quadraphonic microphone, the device is jammed pack with input sensors. The Microsoft Education team promotes Kinect and has prepared over a 100 lessons and activities to promote “active” learning. Microsoft also claims the Kinect may be useful as an assistive technology device and in promoting collaboration.

What you might not know is that the Kinect can plug to your computer and be used as an interface device!
Think about young students actively controlling a 3D ArcGIS Explorer Desktop globe – investigating the Earth while moving arms, legs, and torso to direct navigation, display data, or conduct an analysis. What an interesting way to engage young, energetic learners.

Last week, I demonstrated this concept at the meeting of the Esri Education Team. I connected my Kinect to my Windows laptop and we took turns controlling ArcGIS Explorer Desktop! To get the environment setup, I used the USC’s Institute for Creative Technologies recommendations. This set-up requires installing a set of drivers and then running the FAAST toolkit. Basically, FAAST allows you to create a mapping between Kinect-detected body movements to keyboard strokes. So, when I raise my right arm, the World spins right!

How to make the Kinect work for you:
  • Acquire a stand-alone Xbox 360 Kinect or if you have a Kinect, just get an external USB power supply. Locate a computer with Windows 7, ArcGIS Explorer Desktop, and a free USB port. 
  • Visit the USC Institute for Creative Technologies to install drivers and configure the Kinect. 
  • Create your own mapping file or you can start with my simple mapping file.

Remember, these steps might require a little extra “tech-savvyness” and the FAAST toolkit from USC is an open source (neither a Microsoft nor Esri) project. Use at your own risk.

Post your comments and links using the Kinect to control ArcGIS Explorer Desktop below! Everyone should be able to create a fluid interaction with ArcGIS Explorer Desktop using the Kinect. Good luck!

Written By :-  Tom Baker,Esri Education Manager