Portfolio

Selected research works in algorithm development, spatial analysis and modeling, and web-based geovisualization. Informal records of tech exploration and solutions are shared in my personal blog at Blogging on Earth.

GIS Algorithms

Cartogram Algorithms

Fast computer algorithms for automatic generation of contiguous cartograms with complete topological integrity

Detect and Measure Gerrymandering

A computer algorithm that can detect and delineate gerrymandered political district boundaries

Maximum Inscribed Circles for Distortion Visualization

maximum inscribed circle

Computer algorithms for generating a series of non-overlapping maximum inscribed circles or euql-sized circles for map distortion visulization

One to Many Flow Layout

Computer algorithm for automatic rendering of one-to-many flow data

Spatial Analysis and Modeling

	Date	Title	Description
	Sep 1, 2010	Introurban Migration	Big spatial analytics of intraurban migration using tax parcel data
	Sep 1, 2023	LUXE ABM	A stylized ABM for economic-theory-informed land use change

Web GIS

Animated Cartogram

Animated Cartogram showing 2012 Presidential Election Results

webgis

cartogram

election

The size of geometries does not tell everything. Cartogram is a cartographic technique or product that transforms geometry to show statistics like population or electoral…

Monday, December 1, 2014

Carsi Model

Interactive map showing the modeled COVID-19 prevalance and death

webgis

public health

The CARSI (Center for Advanced Research of Spatial Information) Model uses an embedded recursive SIR (susceptible, infected, removed) model to simultaneously solve for two…

Wednesday, September 1, 2021

Sean C. Ahearn, Shipeng Sun

Global Cropland Excess Nitrogen

Global Excess Nitrogen in Cropland by Various Sources and Geographical Distribution in 2010

webgis

environment

agriculture

The widespread application of fertilizer in croplands has resulted in varying levels of excess nitrogen in the soil. This project is a web-based, interactive visualization…

Sunday, September 1, 2013

New York State Congressional Districting

New York State Congressional Districts Proposed by IRC, legislation, and court in 2022

webgis

redistricting

gerrymandering

The delineation of electoral district boundaries is a fundamental component of democratic practice in the United States. However, gerrymandering—the manipulation of district…

Wednesday, September 1, 2021