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Full-Text Articles in Engineering

Two-Phase Anaerobic Digestion To Reduce The Nox Emission Potential Of Biogas, Nathaniel Manuel Olivas Dec 2015

Two-Phase Anaerobic Digestion To Reduce The Nox Emission Potential Of Biogas, Nathaniel Manuel Olivas

Master's Theses

Anaerobic digestion can be used to decrease the mass of organic wastes to be disposed of while producing useful biogas (CH4 and CO2) for heat or power production, but in air basins with strict emissions limits, biogas combustion is difficult to implement due to the high costs of controlling NOx emissions. NOx production can be minimized by blending H2 gas with CH4 at a volume ratio of 15:85 H2:CH4, which allows burning at ultra-lean air-to-fuel ratios. For biogas systems, a potential low-cost NOx control strategy is to produce H2-CH …


Spatial Variability Of Soil Velocity Using Passive Surface Wave Testing, Daniel Raymond Wagstaffe Dec 2015

Spatial Variability Of Soil Velocity Using Passive Surface Wave Testing, Daniel Raymond Wagstaffe

Master's Theses

Lifelines such as highways, pipelines, telecommunication lines, and powerlines provide communities with vital services, and their functionality is dependent upon the foundation soil that supports them. However, when designing the infrastructure, it can be difficult to know where to test the soil in order to give spatially representative sampling, particularly for long, lifeline structures. Finding this distance requires knowledge of the spatial correlation and/or the spatial variability of the soil parameter (stiffness, cohesion, etc.). But this correlation distance is not typically found in practice because it requires large amounts of data and the costs of retrieving that data can be …


Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts Dec 2015

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO2-supplemented raceway ponds, each with a 33-m2 surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …


Investigating The Correlation Between Freeway Service Levels And Freeway Service Patrol Assists, Nora Chin Sep 2015

Investigating The Correlation Between Freeway Service Levels And Freeway Service Patrol Assists, Nora Chin

Master's Theses

The Bay Area Metropolitan Transportation Commission’s (MTC) Freeway Service Patrol’s highway motorist response service is reporting a reduction in their service levels. We analyze the relationship between the reduction in the Bay Area Freeway Service Patrol’s (FSP) motorist assists and changes in vehicle miles traveled (VMT), California Highway Patrol (CHP) reported incidents, and cover research on the impact of new and old vehicle fleet turnover. VMT and CHP incidents have differential effects on FSP assists. Although incidents occurring on freeways with high traffic flows tend to cause more congestion, the trend in local VMT along Bay Area freeway corridors does …


Measuring The Influence That Components Have On Pedestrian Route Choice In Activated Alleys, Samuel Hirsher Gross Jun 2015

Measuring The Influence That Components Have On Pedestrian Route Choice In Activated Alleys, Samuel Hirsher Gross

Master's Theses

This paper explores how cities have integrated formal planning into improving public space. Through a review of literature on the topic, this the paper identifies the potential design has to renovate narrow streets and alleys, within the public right of way. By preforming an assessment of plans and programs, this paper identifies the common themes or components that have been used by planners, architects, and engineers to improve the urban environment for pedestrians. Based on this information, a pilot study was created to measure the influence the most common components have on pedestrian route choice. The results are then compared …


Using Archived Transit Data To Analyze The Effect Of Rainfall On Transit Performance Measures At The Route Level, Nicholas F. Bleich Jun 2015

Using Archived Transit Data To Analyze The Effect Of Rainfall On Transit Performance Measures At The Route Level, Nicholas F. Bleich

Master's Theses

This study investigates the effect of rainfall on transit performance measures at the route level in the Puget Sound region of Washington State. Transit agencies are required to report certain performance metrics to the Federal Transit Administration (FTA), but performance measures can also be used to evaluate service and provide customers with information regarding the transit system. Using a three-year sample of archived automatic vehicle location (AVL) and hydrologic data the relationships between ridership, travel time, delay, and rainfall were investigated. The analysis of daily ridership and rainfall resulted in no statistically significant results, however, the results are supported by …


Nutrient Transformations In Algae Raceway Ponds Fed Municipal Wastewater, Carter Michael Reiff Jun 2015

Nutrient Transformations In Algae Raceway Ponds Fed Municipal Wastewater, Carter Michael Reiff

Master's Theses

While treating domestic wastewater, algae can be grown and harvested for biofuel production. Water is a vital resource and it is imperative to conserve and reuse as much as possible. Several pilot and lab scale experiments were conducted to further research into a full scale wastewater treatment and biofuel production facility. This thesis will include these topics: nitrogen and phosphorus concentrations of clarified wastewater pond feed, nitrogen and phosphorus transformations by algae, and the potential of algae cell disruption technologies to increase nutrient solubilization.

The pilot scale experiments were conducted using nine 33 m2, 0.3 m deep multi-culture …


Clarification Of Recreational Pool Water Using Biological Additives Produced By Biowish(Tm), Reese Nathaniel Wilson Jun 2015

Clarification Of Recreational Pool Water Using Biological Additives Produced By Biowish(Tm), Reese Nathaniel Wilson

Master's Theses

Effects of commercially available bacterial products were investigated on two common recreational pool contaminants: sunscreen and cyanuric acid (CYA). Microbial products developed by BiOWiSH Technologies, Inc. were tested for enhancing mechanical filtration and water clarification in bench-scale bioreactors, with conditions mimicking those of recreational pool water. Bacterial consortia included proprietary mixes of Bacillus, Lactobacillus and Pseudomonas, and other genera of bacteria. BiOWiSH products are either fermented on a solid substrate consisting of rice bran and soy meal, or they are mixed with a soluble diluent. Twenty-nine BiOWiSH products were tested throughout forty experiments.

Experiments were carried out to determine both …


Locating Optimal Water Quality Monitoring Locations Using Demand Coverage Index Method, Jeffrey Scott Brake Jun 2015

Locating Optimal Water Quality Monitoring Locations Using Demand Coverage Index Method, Jeffrey Scott Brake

Master's Theses

Water quality regulations are always expanding especially in the field of water quality monitoring; however, threats to our water distribution systems still remain. Components of water distribution systems are susceptible to intentional and accidental contamination; therefore, they represent highly vulnerable aspects of our vital infrastructure.

An analysis was performed on a city in California with a population of 30,000 to 40,000 residents. The analysis is performed to determine the optimal locations of monitoring stations throughout the water distribution system. The method presented by Liu and colleagues (Liu et al, 2012) selects the optimal monitoring locations for the virtual California city …


Criticality And Risk Assessment For Pipe Rehabilitation In The City Of Santa Barbara Sewer System, Rossi Carmelo Rossi Ii Jun 2015

Criticality And Risk Assessment For Pipe Rehabilitation In The City Of Santa Barbara Sewer System, Rossi Carmelo Rossi Ii

Master's Theses

Aging sewer infrastructure is posing greater and greater risk to the health and well-being of City residents. Issues can range from pipe blockages in sewer laterals to Sanitary Sewer Overflows. This thesis develops a risk analysis method that can be used by municipalities to maintain and rehabilitate sewer assets. Risk combines the effect of Likelihood of Failure (LOF) and Consequence of Failure (COF) to perform a complete two-dimensional analysis that allows for relative comparison between different pipes in the system. The LOF rating has been equated to pipe integrity while the COF rating was related to the environmental, economic, and …


Treatment Of Petroleum Hydrocarbons In Oil-Based Drill Cutting Mud Using Biowish Bioaugmentation Products, Diego Jose Cardenas Zepeda Jun 2015

Treatment Of Petroleum Hydrocarbons In Oil-Based Drill Cutting Mud Using Biowish Bioaugmentation Products, Diego Jose Cardenas Zepeda

Master's Theses

The efficacy of BiOWiSHTM-Thai Aqua, a commercially discontinued microbial product, in remediating oil based drill-cutting mud (DCM) was researched in this study. Experimentation was performed directly on DCM and on sand contaminated with oil extracted from DCM. A gas chromatograph-mass spectrometrer and a respirometer were used for analysis of total petroleum hydrocarbons (TPH) and CO2 production respectively. Five experiments were analyzed by TPH extraction and analysis; four experiments were analyzed by respirometric analysis. The specific microcosm conditions tested in the experiments were control, nutrient-only control, and bioaugmentation product.

This study concluded that there might be potential for bioaugmentation of TPH …


A Risk Analysis Model For The Maintenance And Rehabilitation Of Pipes In A Water Distribution System: A Statistical Approach, Hernan Cortez Jun 2015

A Risk Analysis Model For The Maintenance And Rehabilitation Of Pipes In A Water Distribution System: A Statistical Approach, Hernan Cortez

Master's Theses

ABSTRACT

The network of pipes in potable water distribution systems (WDS) are comprised of thousands of pipes made of various materials including PVC, concrete, cast iron, and steel, among several others. The pipes are subjected to internal and external conditions that lead to their failure. Stress conditions include, but are not limited to internal pressures, traffic loading, and corrosion. The deterioration of a pipe decreases its mechanical strength which results in an increase of its probability of failure. Failures lead to loss of service which translates to loss of money due to the cost of repairs and buildup of traffic …


Methodologies For Simplified Lifeline System Risk Assessments, Michael Germeraad May 2015

Methodologies For Simplified Lifeline System Risk Assessments, Michael Germeraad

Master's Theses

Natural hazards are a growing risk across the globe. As regions have urbanized, single events impact greater proportions of the population, and the populations within those regions have become more dependent on infrastructure systems. Regional resilience has become closely tied to the performance of infrastructure. For a comprehensive risk assessment losses caused by lifeline outage must be considered alongside structural and nonstructural risks. Many well developed techniques quantify structural and nonstructural risk; however, there are insufficient procedures to determine the likelihood of lifeline outages. Including lifelines in seismic assessments will provide a comprehensive risk, improving a decision maker’s capacity to …


Development And Lab Calibration Of The Pnuematic In-Situ Soil Caving Index Sampler (Piscis), Michael A. Grolle Mar 2015

Development And Lab Calibration Of The Pnuematic In-Situ Soil Caving Index Sampler (Piscis), Michael A. Grolle

Master's Theses

The caving/sloughing of sandy layers into drilled shafts is a common and costly phenomenon in the drilling industry. A prototype soil-testing device known as the Pneumatic In-situ Soil Caving Index Sampler (PISCIS) has been developed to test sandy layers above the water table for their propensity to cave/slough into a drilled shaft during the drilling process. The PISCIS fits down a Cone Penetration Test (CPT) hole and uses air pressure to agitate a sample off of the hole wall that is then collected and weighed. Large-scale lab testing was conducted using sand under a variety of simulated overburden pressures and …


Nutrient Removal From Clarified Municipal Wastewater Using Microalgae Raceway Ponds, Justin Andrew Kraetsch Mar 2015

Nutrient Removal From Clarified Municipal Wastewater Using Microalgae Raceway Ponds, Justin Andrew Kraetsch

Master's Theses

Shallow, mixed raceway ponds can be used to grow microalgae for the dual purposes of wastewater treatment and biofuel feedstock production. To improve the environmental sustainability of microalgae biofuels and to alleviate resource limitations, nutrients remaining after biofuel production should be recycled for additional cultivation. This thesis considers three topics: wastewater treatment by algae, nitrogen and phosphorus assimilation by algae, and algae cell disruption to facilitate nutrient recovery.

The main experimental work was done in pilot raceway ponds growing polycultures of microalgae on clarified municipal wastewater. In addition, two lab-scale pretreatment technologies were tested for their ability to disrupt cells, …