Geographic Information Sciences Commons^™

Gis Professional Certification 2.0: Putting Gis To The Test, Nancy Obermeyer

Purdue GIS Day

No abstract provided.

Gis Day 2014 Additional Resources, Larry Theller

Purdue GIS Day

No abstract provided.

Using Census Bureau Data For Current And Historical Gis Research, Bert Chapman

Libraries Faculty and Staff Presentations

Provides examples of how geographic information system (GIS) data can be used to conduct historical and contemporary research using Census Bureau data and mapping and other resources. Such data and mapping can enhance understanding of historical and contemporary subjects in a multidisciplinary variety of topics.

Common Metrics For Web-Based Mapping Applications In Academic Libraries, Ningning Kong, Tao Zhang, Ilana Stonebraker

Libraries Faculty and Staff Scholarship and Research

Purpose – This study aims to establish common metrics for web-based mapping applications to facilitate user decision making and enhance information providers’ product design.

Design/methodology/approach – The metrics were developed from a combination of literature review and case studies. From the literature review, we identified three major areas of assessment for web-based mapping applications. We then studied six online applications to refine the metrics.

Findings – Our results suggest that web-based mapping applications can be evaluated from three major aspects: data content, GIS functionality, and usability. We have developed detailed measures for each factor through our evaluation of the six …

Manifold Learning Based Spectral Unmixing Of Hyperspectral Remote Sensing Data, Jun-Hwa Chi

Open Access Dissertations

Nonlinear mixing effects inherent in hyperspectral data are not properly represented in linear spectral unmixing models. Although direct nonlinear unmixing models provide capability to capture nonlinear phenomena, they are difficult to formulate and the results are not always generalizable. Manifold learning based spectral unmixing accommodates nonlinearity in the data in the feature extraction stage followed by linear mixing, thereby incorporating some characteristics of nonlinearity while retaining advantages of linear unmixing approaches. Since endmember selection is critical to successful spectral unmixing, it is important to select proper endmembers from the manifold space. However, excessive computational burden hinders development of manifolds for …

Identifying Ditch Geometry And Top Of The Bank Location Using Airborne Lidar Point Cloud, Naime Celik

Open Access Theses

The geometry of agricultural drainage ditches is very important in crop production as it impacts drainage of cropland and affects vegetation and soil erosion along the banks of the ditches. Thus, implementation of water conservation and management practices in engineered and natural ditches necessitates determination of ditch geometry along the reach of the ditch. This study explores the use of airborne commercial Light Detection and Ranging (LiDAR) technology to identify the top of the ditch banks. The method was developed to obtain the normalized cross sectional shape of the ditch using one-dimensional spline fits to ground classified points from the …

The Microsoft Geospatial Library, Michael Kallay

2011 Symposium on Data-Driven Approaches to Droughts

In SQL Server 2008, Microsoft introduced support for geospatial data, with a rich set of spatial queries and constructions, in both Cartesian and geodetic coordinates. Most of this functionality is also available as an independent (free download) .NET library. This talk will focus on this library, touching on the differences in functionality between its TSQL and C# interfaces.

Land Use As It Relates To Land Slope, James D. Plourde, Bryan C. Pijanowski

GIS Day

The goal of this project is to analyze the relationship between the slope of land and agricultural land use. The output was analyzed to determine a threshold point at which agriculture practices drop off in relation to higher slope values. Slope of the land is important to agricultural practices because it impacts drainage and net crop primary production. Agricultural land was extracted from the 2001 National Land Cover Dataset using reclassification tools in ArcGIS 9.3. The slope of the contiguous United States was derived from the United States Geological Survey National Elevation Dataset by using the slope tool in the …

Lower Tropospheric Temperature Variability Over The Usa: A Gis Approach, Souleymane Fall, Dev Niyogi, Gilbert L. Rochon

GIS Day

We use the high resolution North American Regional Analysis (NARR) dataset to build for the United States a Temperature Change Index (TCI) based on four contributing variables derived from the layer-averaged temperature and lapse rate of the 1000mb - 700mb layer (near-surface to 3000 meters) for the 1979-2008 period. The analysis uses Geographic Information Systems (GIS) methods to identify distinct regional patterns based on aggregate temperature trends and variability scores. The resulting index allows us to identify and compare regions that experience high (low) temperature trends and variability that are referred to as hot spots (cold spots). The upper Midwest …