Physical Sciences and Mathematics Commons^™

Performance Assessment Of Gnss Augmentation System Using Quasi-Zenith Satellite System For Real-Time Precise Positioning Method In Indonesia, Irwan Gumilar, Brian Bramanto, Rifky Yusuf Ananta, Dwi Haryanto, Hasanuddin Zaenal Abidin, Surono Surono, Nobuhiro Kishimoto

International Journal of Geospatial and Environmental Research

The Quasi-Zenith Satellite System (QZSS) is one of the GNSS technologies owned by the Japanese government, which orbits around East Asia, Asia Pacific, and Oceania. One of the advantages of the QZSS satellite is that it corrects the measurements using precise ephemeris, clock, and other augmenting corrections, and is primarily used for the Real-Time Precise Point Positioning (RTPPP) method. This study aimed to examine the QZSS system's performance for RTPPP measurements in Indonesia. Magellan System Japan's (MSJ) receiver was applied to collect the GNSS and the augmenting data to perform the RTPPP. RTPPP method was then made into the static …

A Comparative Study Of Delineated Watersheds Using Aster And Srtm In Johor, Malaysia, Nafisah Khalid, Maisarah Abdul Halim, Siti Nur A’Tirah Shahimi

International Journal of Geospatial and Environmental Research

The availability of watershed delineation that has been generated from DEM data is difficult to obtain and the accessibility of DEM data which are unrestricted and precise are hard to obtain in Malaysia. The aim of this study is to examine the accuracy of watershed delineation between Digital Elevation Model (DEM) from ASTER and SRTM in Johor State Malaysia. In this study, free online data sources from USGS website are used to delineate watershed from ASTER and SRTM satellite imageries. The hydrological modelling tool namely ArcSWAT is utilized to delineate watersheds for both DEM datasets. Both DEM data that had …

Exploratory Spatial Data Analysis In Traffic Safety, Amin Azimian, Dimitra Pyrialakou

International Journal of Geospatial and Environmental Research

This paper presents an exploratory spatial data analysis (ESDA) of road traffic crashes at different severity levels in West Virginia (WV). Although ESDA can support transportation safety decision-making by helping planners understand and summarize crash data, it is underutilized in practice. This paper describes the application of five representative easy-to-use method to identify crash patterns and high crash-risk counties in WV. Analysis of crash data from 2010 to 2015 indicated that traffic crashes in WV were not spatially correlated. However, crash severities were found to be positively correlated.

Identifying Geographical Interdependency In Critical Infrastructure Systems Using Open Source Geospatial Data In Order To Model Restoration Strategies In The Aftermath Of A Large-Scale Disaster, Varun Ramachandran, Tom Shoberg, Suzanna Long, Steven Corns, Hector Carlo

International Journal of Geospatial and Environmental Research

In the wake of a large-scale disaster, strategies for emergency search and rescue, short-term recovery and medium- to long-term restoration are needed. While considerable effort is geared to developing strategies for the former two options, little comprehensive guidance exists on the latter. However, medium- to long-term restoration has a significant effect on local, regional and national economies and is essential to community vitality. In part, the deficit of robust strategies can be linked to the complexity in the data acquisition and limited methodologies to understand the interconnectedness of the relevant systems elements. This research utilizes infrastructure data for Supply Chain …

A Soil Parameters Geodatabase For The Modeling Assessment Of Agricultural Conservation Practices Effects In The United States, Mauro Di Luzio, Martin L. Norfleet, Jeffrey G. Arnold, Jimmy R. Williams, James R. Kiniry

International Journal of Geospatial and Environmental Research

Soil parameters for hydrology modeling in cropland dominated areas, from the regional to local scale, are part of critical biophysical information whose deficiency may increase the uncertainty of simulated conservation effects and predicting potential. Despite this importance, soil physical and hydraulic parameters lack common, wide-coverage repositories combined to digital maps as required by various hydrology-based agricultural water quality models.

This paper describes the construction of a geoprocessing workflow and the resultant hydrology-structured soil hydraulic, physical, and chemical parameters geographic database for the entire United States, named US-SOILM-CEAP. This database is designed to store a-priori values for a suit of models, …

Impacts Of Remotely Sensed Land Use Data On Watershed Hydrologic Change Assessment, Gi-Choul Ahn, Steven I. Gordon, Carolyn J. Merry

International Journal of Geospatial and Environmental Research

Urbanization affects the stream system of a watershed. Increased urbanization alters the land cover and surface characteristics, the stream channel characteristics, and pollutant load of a stream system by increasing the amount of impervious surface. Once rural, forest, or wetland areas are changed to streets, highways, parking lots, sidewalks, and building rooftops. This results in large volumes of runoff being generated for an intense storm over a relatively short time period. As a result, sensitive ecosystems are likely to be damaged by increased urbanization.

Projecting the impact of land use changes on a watershed scale often requires the use of …

Assessing Survivability Of The Beijing Subway System, Yan Li, Hyun Kim

International Journal of Geospatial and Environmental Research

The Beijing subway system, the third largest in the world, serves more than ten million passengers a day. As Beijing is the capital city of China and thus a booming urban center, its subway system has experienced rapid evolution from a local single line system to a complicated network. Due to its constantly increasing complexity, the system is both a critical asset for a local transit artery and a bridge between intercity transportation modes, increasing the issue of network survivability in the face of potential outages of network components. In this study, we provide a connectivity-based survivability measure with which …