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Full-Text Articles in Engineering
Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar
Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar
Dissertations
The sites at which the development is hindered by real or perceived contamination are called as Brownfield sites. It is a common trend in industry to develop these types of sites with surface and peripheral containments. It might prove unwise to develop the sites in this manner from a long term perspective without considering the associated risk. Because of this, a model has been proposed for long term risk assessments of brownfield containments.
Objectives of this study were to develop a contaminant transport model for flow of contaminants towards the surface and peripheral containments inside the site, a model for …
Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen
Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen
Dissertations
Grinding process is introduced to provide fine particles of coal fly ash that enhances the strength gain of cement mortars. It is discovered that grinding can make all the studied fly ashes more suitable for concrete use at higher replacement value than previously anticipated even when the effect of high carbon content is considered.
In this study, new mechanisms for strength gain of fly ash mortars are proposed. They are dispersion and nucleation, which are results from the presence of fly ash in the cement mortar. These effects are shown to enhance the hydration of cement. The pozzolanic action of …
A Methodology For Solving The Network Toll Design Problem, Mei Chen
A Methodology For Solving The Network Toll Design Problem, Mei Chen
Dissertations
Congestion pricing has been regarded as an efficient method to reduce network-wide travel cost. In this dissertation, a methodology for toll design is developed to provide policy-makers with suggestions on both where to charge tolls and how much the tolls should be. As opposed to the traditional approach of marginal social cost pricing, this methodology is capable of dealing with the more realistic case, in which only a small number of links can be tolled. Furthermore, this methodology is expanded to accommodate multiple user groups.
The toll design problem can be formulated using both deterministic and stochastic route choice models. …
Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim
Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim
Dissertations
The study of Water Treatment Plant (WTP) residuals is of recent origin and very little information is available in literature regarding these residuals. These waste materials have high solids contents, even in the mechanically dewatered condition, making it difficult to handle. These, along with stringent environmental regulations have forced the water utilities to look for new disposal options for these residuals. For this purpose as well as for evaluating suitable options for the beneficial reuse of residuals, it is essential to characterize WTP residuals.
As the dewatered residuals are plastic, the researcher may be prompted to treat these materials as …
Optimization Of Urban Traffic Control Strategies By A Network Design Model, Wu Sun
Optimization Of Urban Traffic Control Strategies By A Network Design Model, Wu Sun
Dissertations
The efficiency of congested urban transportation networks can be improved by implementing appropriate traffic control strategies, such as signal control timing, turning movement control; implementation of one-way traffic policies, lane distribution controls etc.. In this dissertation, the following strategies are addressed: 1) Intersection left turn addition/deletion, 2) Lane designation,. and 3) Signal optimization.
The analogy between the network design problem (NDP) and the optimization of traffic control strategies motivated the formulation of an urban transportation network design problem (UTNDP) to optimize traffic control strategies. An UTNDP is a typical bi-level programming program, where the lower level problem is a User …
Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski
Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski
Dissertations
The objective of this study was the development of a new computer program called PF-Model to analyze pneumatic fracturing of geologic formations. Pneumatic fracturing is an in situ remediation process that involves injecting high pressure gas into soil or rock matrices to enhance permeability, as well as to introduce liquid and solid amendments. PF-Model has two principal components: (1) Site Screening, which heuristically evaluates sites with regard to process applicability; and (2) System Design, which uses the numerical solution of a coupled algorithm to generate preliminary design parameters.
Designed as an expert system, the Site Screening component is a high …