Day: July 19, 2010

Temporal Analysis of Sweet Chestnut Decline in Northeastern Portugal using Geostatistical Tools

/ Matt Artz

ISHS Acta Horticulturae 866: I European Congress on Chestnut – Castanea 2009

J. Castro, J.C. Azevedo, and L. Martins

“The rising demand for sweet chestnut (Castanea sativa) in Portugal and elsewhere in Europe has led to more intensive management practices to increase nut production. This intensification has potentially increased the widespread of ink and chestnut blight diseases, causing decline in sweet chestnut orchards health and production and limiting the establishment of new planted areas. In this study we estimated chestnut decline along the last twenty years (1986 to 2006) in the northern part of Portugal using 1986, 1995 and 2006 aerial photography to quantify the damage at the tree level within fixed sample plots according to a categorical scale. Mean damage and damage variance in each date, however, were not significantly different. Geostatistical analyses indicated, however, changes in the spatial distribution of damaged and undamaged areas over time. The spread of decline in the region of study was estimated using Kriging based on the spherical model. During the examined period we observed spread of chestnut decline and increasing damage levels in regions where damage is systematically high. The chestnut productive surface in the region has increased in the last twenty years because new plantations exceeded mortality areas. The spatial analyses applied here have made clearer the relations between the spread of chestnut decline and geographical variables.”

Multi-temporal Analysis for Mexico City Aquifer using a GIS-based on Measured Data

/ Matt Artz

ISMAR7, 09-13 October 2010, Abu Dhabi

Rosío Ruiz and Gerardo Ruiz

“The growth of the population in Mexico City, demand increased amount of water day with day today for providing the vital fluid is resorted to the exploitation of sources, both internal and external, the aquifer of Mexico City, the dependency of groundwater extracted from wells makes it necessary to review the conditions of the aquifer for evolutionary in the aquifers conditions; these revisions are made from the depths of groundwater; measurements obtained values can infer the effect that brings with it the exploitation of this source and at the same time can implement actions to enable their recovery.

“The main objective of this paper is to introduce a system that enables storage of information, analysis and visualization of measurements of static, dynamic levels and specific flow, as well as behavior in the Geographic Information System to support a better understanding of the modeling of the aquifer and better decision making in the operation of the network of the Valley of Mexico wells GIS-based data measured.

“Presents a multi-temporal analysis of the evolution of groundwater until 2009 the aquifer of area Metropolitan of the Mexico City, for which the static and dynamic level of 225 wells measurement was made. Perform hydraulic balance of groundwater, determining degree of overexploitation. Check changes in the static levels of the aquifer system from policies. Start the historical record of dynamic measurements in wells in operation. Determine the behavior of the aquifer in recent years. Differentiate areas of greater exploitation of those recovering.”

Adaptive Cell Tower Location Using Geostatistics

/ Matt Artz

Geographical Analysis, Volume 42 Issue 3, Pages 227 – 244, Published Online 01 July 2010

Mohan R. Akella, Eric Delmelle, Rajan Batta, Peter Rogerson, and Alan Blatt

“In this article, we address the problem of allocating an additional cell tower (or a set of towers) to an existing cellular network, maximizing the call completion probability. Our approach is derived from the adaptive spatial sampling problem using kriging, capitalizing on spatial correlation between cell phone signal strength data points and accounting for terrain morphology. Cell phone demand is reflected by population counts in the form of weights. The objective function, which is the weighted call completion probability, is highly nonlinear and complex (nondifferentiable and discontinuous). Sequential and simultaneous discrete optimization techniques are presented, and heuristics such as simulated annealing and Nelder–Mead are suggested to solve our problem. The adaptive spatial sampling problem is defined and related to the additional facility location problem. The approach is illustrated using data on cell phone call completion probability in a rural region of Erie County in western New York, and accounts for terrain variation using a line-of-sight approach. Finally, the computational results of sequential and simultaneous approaches are compared. Our model is also applicable to other facility location problems that aim to minimize the uncertainty associated with a customer visiting a new facility that has been added to an existing set of facilities.”

Read and Write ESRI Shape Files With R

/ Matt Artz

…from the National Center for Ecological Analysis and Synthesis…

“The ESRI Shape File is a widely used standard data format for storing vector-format geophysical data. R provides several different techniques to import ESRI shape file.

“This example demonstrates use of three R geospatial packages to read and write ESRI Shape Files.”

The Framework of a Geospatial Semantic Web-based Spatial Decision Support System for Digital Earth

/ Matt Artz

International Journal of Digital Earth, Volume 3, Issue 2 June 2010 , pages 111 – 134

Chuanrong Zhang; Tian Zhao; and Weidong Li

“While significant progress has been made to implement the Digital Earth vision, current implementation only makes it easy to integrate and share spatial data from distributed sources and has limited capabilities to integrate data and models for simulating social and physical processes. To achieve effectiveness of decision-making using Digital Earth for understanding the Earth and its systems, new infrastructures that provide capabilities of computational simulation are needed. This paper proposed a framework of geospatial semantic web-based interoperable spatial decision support systems (SDSSs) to expand capabilities of the currently implemented infrastructure of Digital Earth. Main technologies applied in the framework such as heterogeneous ontology integration, ontology-based catalog service, and web service composition were introduced. We proposed a partition-refinement algorithm for ontology matching and integration, and an algorithm for web service discovery and composition. The proposed interoperable SDSS enables decision-makers to reuse and integrate geospatial data and geoprocessing resources from heterogeneous sources across the Internet. Based on the proposed framework, a prototype to assist in protective boundary delimitation for Lunan Stone Forest conservation was implemented to demonstrate how ontology-based web services and the services-oriented architecture can contribute to the development of interoperable SDSSs in support of Digital Earth for decision-making.”

The City of Frisco, Texas, Earns Esri President’s Award

/ Matt Artz

SAFER GIS Application Provides Enhanced School Public Safety

The City of Frisco, Texas, was honored with the Esri President’s Award for outstanding geographic information system (GIS) work, particularly in providing improved public safety for its schools. The award was presented Monday, July 12, at the 2010 Esri International User Conference, held in San Diego, California.

The city developed an application called Situational Awareness For Emergency Response (SAFER), which provides fire, police, and emergency responders with access to maps and live data feeds while en route to a school incident. SAFER takes advantage of Esri business partner GeoComm’s GeoLynx solution, which is built using Esri technology. The system became fully operational in 2009.

“The project makes the schools, students, and first responders safer,” says Susan Olson, GIS manager, City of Frisco, Texas. “It enables city public safety departments to better serve the school district and will eventually help all commercial business owners. Implementing this system has allowed the departments to reduce operations costs by having all the relevant information in one place. It lowers risk and better prepares responders on the way to an emergency.”

“The city’s GIS, and the SAFER project in particular, is an example of how smaller local government agencies can do important work cost-effectively,” says Russ Johnson, public safety manager, Esri. “The GIS team leveraged the city’s local government ELA [enterprise license agreement] to open up more GIS capabilities for other departments. One of the results is that the city is better prepared to take action in an emergency.”

The city uses GeoLynx Mobile software, deployed on mobile data computers in its emergency vehicles, to access GIS information remotely. It has GeoLynx 9-1-1 at its dispatch stations, and the emergency operations center uses a custom ArcGIS Server Web application. SAFER integrates multiple databases and gives people information such as aerial maps (obliques and orthophotography), footage from hundreds of school surveillance cameras, dispatch data, campus photos, floor plans, and automated vehicle locations.

With SAFER, users can

  • Visualize an incident for immediate planning and response.
  • Improve communication between first responders and other staff.
  • Make critical decisions using a common operating picture.

“The City of Frisco’s SAFER program demonstrates the role that GIS can play in enhancing communications for multiple agencies and ultimately improving emergency response to its citizens,” says Jody Sayre, vice president of Client Services at GeoComm. “The project team was highly engaged in this project from day one, and it is very deserving of this award.”

SAFER is just one of the city’s successful GIS programs. Other GIS applications include CityWorks for public works work order management, reverse 911 notifications, carrying out law enforcement warrants, and water utility billing. These GIS applications help the city manage growth; according to recent census information, Frisco is the fastest-growing city in the United States. GIS helps it design new infrastructure and improve existing resources to accommodate this continued growth.

[Source: ESRI press release]

Towards Real-Time Geodemographics: Clustering Algorithm Performance for Large Multidimensional Spatial Databases

/ Matt Artz / 1 Comment

Transactions in GIS, Volume 14 Issue 3, June 2010, p 283-297

Muhammad Adnan, Paul A Longley, Alex D Singleton, and Chris Brunsdon

“Geodemographic classifications provide discrete indicators of the social, economic and demographic characteristics of people living within small geographic areas. They have hitherto been regarded as products, which are the final “best” outcome that can be achieved using available data and algorithms. However, reduction in computational cost, increased network bandwidths and increasingly accessible spatial data infrastructures have together created the potential for the creation of classifications in near real time within distributed online environments. Yet paramount to the creation of truly real time geodemographic classifications is the ability for software to process and efficiency cluster large multidimensional spatial databases within a timescale that is consistent with online user interaction. To this end, this article evaluates the computational efficiency of a number of clustering algorithms with a view to creating geodemographic classifications “on the fly” at a range of different geographic scales.”

Adapting to the Impacts of Climate Variability and Change on Agriculture

/ Matt Artz / 1 Comment

Belay Tseganeh Kassie, H. Hengsdijk, R. Roetter, H. van Keulen, and Girma Mamo

This project is part of the joint Finnish-Netherlands-Ethiopian project Exploring alternative scenarios of adapting to climate change (AlterCLIMA) financed by the Academy of Finland, Development Research programme.

“Ethiopia is highly vulnerable to climate variability and change, due to its dependence on rainfed agriculture, low level of socio-economic development, and limited disaster management skills. Quantitative climate impact assessments on Ethiopian agriculture are scarce. This study is being conducted in two case studies, the Central Rift Valley and North Wollo, differing in environmental conditions, food security, poverty, and adaptive capacity.”