Infrastructure Engineering - Research Publications
Now showing items 1-12 of 1059
Optical Sensing of Vegetation Water Content: A Synthesis Study
(Institute of Electrical and Electronics Engineers, 2015-04-01)
Vegetation water content (VWC) plays an important role in parameterizing the vegetation influence on microwave soil moisture retrieval. During the past decade, relationships have been developed between VWC and vegetation indices from satellite optical sensors, in order to create large-scale VWC maps based on these relationships. Among existing vegetation indices, the normalized difference vegetation index (NDVI) and the normalized difference water index (NDWI) have been most frequently used for estimating VWC. This work compiles and inter-compares a number of equations developed for VWC derivation from NDVI and NDWI using satellite data and ground samples collected from field campaigns carried out in the United States, Australia, and China. Four vegetation types are considered: corn, cereal grains, legumes, and grassland. While existing equations are reassessed against the entire compiled data sets, new equations are also developed based on the entire data sets. Comparing with existing equations, results show superiorities for the new equations based on statistical analysis against the entire data set. NDWI1640 and NDVI are found to be the preferred indices for VWC estimation based on the availability and the error statistics of the compiled data sets. It is recommended that the new equations can be applied in the future global remote sensing application for VWC map retrieval.
Time efficient post-disaster housing reconstruction with prefabricated modular structures
(The Urban International Press, 2014-09-01)
With many natural disasters such as earthquakes, cyclones, bushfires and tsunamis destroying human habitats around the world, post-disaster housing reconstruction has become a critical topic. The current practice of post-disaster reconstruction consists of various approaches that carry affected homeowners from temporary shelters to permanent housing. While temporary shelters may be provided within a matter of days as immediate disaster relief, permanent housing can take years to complete. However, time is critical, as affected communities will need to restore their livelihoods as soon as possible. Prefabricated modular construction has the potential to drastically improve the time taken to provide permanent housing. Due to this time-efficiency, which is an inherent characteristic of modular construction, it can be a desirable strategy for post-disaster housing reconstruction. This paper discusses how prefabricated modular structures can provide a more time-efficient solution by analysing several present-day examples taken from published postdisaster housing reconstruction processes that have been carried out in different parts of the world. It also evaluates how other features of modular construction, such as ease of decommissioning and reusability, can add value to postdisaster reconstruction processes and organisations that contribute to the planning, design and construction stages of the reconstruction process. The suitability of modular construction will also be discussed in the context of the guidelines and best practice guides for post-disaster housing reconstruction published by international organisations. Through this analysis and discussion, it is concluded that prefabricated modular structures are a highly desirable time-efficient solution to post-disaster housing reconstruction.
Spatio-temporal event detection using probabilistic graphical models (PGMs)
(IEEE xplore, 2013)
Event detection concerns identifying occurrence of interesting events which are meaningful and understandable. In dynamic fields, as time passes the attribute of phenomenon varies in spatial locations. Detecting events in dynamic fields requires an approach to deal with the highly granular data arriving in real time. This paper proposes a spatiotemporal event detection algorithm in dynamic fields which are monitored by wireless sensor networks (WSNs). The algorithm provides a method using probabilistic graphical models (PGMs) in WSNs to cope with the uncertainty of sensor readings. The algorithm incorporates the ability of Markov chains in temporal dependency modelling and Markov random fields theory to model the spatial dependency of sensors in a distributed fashion. Experimental evaluation of the proposed algorithm demonstrates that the decentralized approach improves the F1-score to 82% and 29% better precision than simple threshold technique. In addition, the performance of the algorithm was evaluated and compared with respect to the scalability (in terms of communication complexity). In comparison with the centralized approach the decentralized algorithm can substantially improve the scalability of communication in wireless sensor networks.
mo' justis: the law of defamation in Texas
(The Victorian Bar, 2008/2009)
When the local newspaper published a satirical article lampooning the justice dispensed in the local juvenile court the judge and prosecutor sued for libel and the case continued for five years before the newspaper’s right to publish was upheld. The application to appeal the decision in favour of the newspaper was denied by the US Supreme Court.
The brethren updated [Review of the book The nine: inside the secret world of the Supreme Court]
This book looks at the process underlying the nomination, confirmation and appointment of some US Federal judges including the resignation of Justice O'Connor of the Supreme Court.
[Review of the book How the states got their shapes]
This book considers the political and legal reasons underlying the present location of the borders (or boundaries) of the states making up the United States of America.