Matching Items (42)

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Tendencies of United States Bicycle Commuters: An Analysis of the 2017 National Household Travel Survey

Description

Approximately 1% of the total working population within the United States bikes as their primary mode of commute. Due to recent increased in bicycle facilities as well as a focus on alternative modes of transport, understanding the motivations and type

Approximately 1% of the total working population within the United States bikes as their primary mode of commute. Due to recent increased in bicycle facilities as well as a focus on alternative modes of transport, understanding the motivations and type of people who bike to work is important in order to encourage new users.
In this project, a literature review was completed as well as data analysis of the National Household Travel Survey (NHTS) in order to find specific populations to target. Using these target populations, it is suggested that advertising and workplace encouragement occur to persuade more people to bike to work. Through data analysis it was found that the most impactful variables were the region of the country, gender, population density, and commute distance. Bicycle commuters statistically had fewer vehicles in their households and drove less miles annually.
There were five main target groups found through this analysis; people who bike for other reasons besides work and live in a city with more than 4,000 people per square mile, young professionals between 19-39, women in regions with separated bicycle facilities, those with low vehicle availability, and environmentally conscious individuals. Working to target these groups through advertising campaigns to encourage new users, as well as increasing and improving bicycle facilities, will help create more new bicyclists.

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Date Created
2019-05

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AGE, GENDER, AND TRAVEL SOCIALIZATION EFFECTS ON CHILDHOOD AND ADULTHOOD TRANSIT USE

Description

The objective of this research paper is to analyze and determine the relationships between childhood and adulthood transit behavior. The study investigates gender differences for each generation regarding childhood transit experiences. Childhood travel socialization was studied to understand its effects

The objective of this research paper is to analyze and determine the relationships between childhood and adulthood transit behavior. The study investigates gender differences for each generation regarding childhood transit experiences. Childhood travel socialization was studied to understand its effects on childhood transit experience and perception. Lastly, childhood transit experience and perception were analyzed to determine their effect on adult transit usage. The variables the study analyzed were childhood peer impression of public transit, parental opinion of the safety of public transit, and the respondents’ childhood public transit experience. These variables were investigated to determine if they had an effect on adult use of public transit. The survey Transit Center’s Who’s On Board: 2014 Mobility Attitudes Survey (WOBMAS) was used to perform these analyses. The results showed that gender equality appears to be increasing in younger generations with respect to their ability to travel alone on public transit. In addition, men were more likely to travel by themselves on public transit when compared to women. There is a direct correlation between childhood travel socialization and childhood transit experience and opinion. However, there appears to be no correlation between childhood travel socialization and a child’s likeliness to travel on public transit alone. Childhood travel socialization had a counterintuitive effect on adult transit usage. On the contrary, it appears that childhood experience is significantly linked to adult transit usage. The data suggests that the earlier a person travels on public transit alone, the more likely they are to ride it as an adult.

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Date Created
2019-05

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Effective Stabilization of Expansive Soils

Description

Expansive soils in the United States cause extensive damage to roadways, buildings, and various structures. There are several treatment or methods of mitigation for these expansive soils. These treatments can be physical or chemical treatments that serve to provide more

Expansive soils in the United States cause extensive damage to roadways, buildings, and various structures. There are several treatment or methods of mitigation for these expansive soils. These treatments can be physical or chemical treatments that serve to provide more suitable building qualities for foundations and roadways alike. The main issue with expansive soils, is the volumetric variations, which are known as swelling and consolidation. These behaviors of the soil are usually stabilized through the use of lime solution, Portland Cement Concrete, and a newer technology in chemical treatments, sodium silicate solutions. Although the various chemical treatments show benefits in certain areas, the most beneficial method for stabilization comes from the combination of the chemical treatments. Lime and Portland cement concrete are the most effective in terms of increasing compressive strength and reduction of swell potential. However, with the introduction of silicate into either treatment, the efficacy of the treatments increases by a large amount lending itself more as an additive for the former processes. Sodium silicate solution does not lend itself to effectively increase the compressive strength of expansive soils. The sodium silicate solution treatment needs extensive research and development to further improve the process. A proposed experiment plan has been recommended to develop trends of pH and temperature and its influence on the effectiveness of the treatment. Nonetheless, due to the high energy consumption of the other processes, sodium silicate solution may be a proper step in decreases the carbon footprint, that is currently being created by the synthesis of Portland Cement Concrete and lime.

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Date Created
2018-12

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Life Cycle Sustainability Analysis (LSCA) of Enzyme-Induced Carbonate Precipitate (EICP)

Description

Current practice and a new technology for mitigating fugitive dust on construction sites are compared on the basis of economic, environmental and social impacts for this assessment. Fugitive dust can have serious health impacts, such as repertory illnesses and valley

Current practice and a new technology for mitigating fugitive dust on construction sites are compared on the basis of economic, environmental and social impacts for this assessment. Fugitive dust can have serious health impacts, such as repertory illnesses and valley fever, on affected persons and is regulated by the Environmental Protection Agency and enforced by state and local agencies. Current practice consists of either relatively continuous application of potable water, a valuable resource, or application of expensive polymers, however, water application is considered the best available technology (BAT). The new technology, developed by the Center of Bio-medicated and Bio-inspired Geotechnics at Arizona State University, consists of application of Enzyme-Induced Carbonate Precipitate (EICP) to create an erosion-resistant crust. This crust is considered a "one and done" solution, until it is disturbed, however will last longer and stay more effective than quickly evaporating water. Future work will need to include how much disturbance is required to disturb the crust until ineffective towards mitigating fugitive dust. Results of the comparison show that a single EICP treatment produces 37 times less pollutants, uses 41 times less water and is 1.14 times cheaper than using water treatment to mitigate fugitive dust on a 7 acre site for 2 weeks (14 days). 14 days is the threshold at where EICP treatment becomes less expensive than water application for the purpose of mitigating fugitive dust. The EICP treatment benefits include lowering global warming inducing emissions, providing better air quality, becoming more cost effective, staying constantly effective to mitigate fugitive dust, and saving potable water.

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Date Created
2018-12

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Risk Assessment and Toxicity to Terrestrial Plants of Soil Contaminated by Heavy Hydrocarbons and Treated with Ozone

Description

Terrestrial crude oil spills compromise a soil’s ability to provide ecosystem services by inhibiting plant life and threatening groundwater integrity. Ozone gas, a powerful oxidant, shows promise to aid in soil recovery by degrading petroleum hydrocarbons into more bioavailable and

Terrestrial crude oil spills compromise a soil’s ability to provide ecosystem services by inhibiting plant life and threatening groundwater integrity. Ozone gas, a powerful oxidant, shows promise to aid in soil recovery by degrading petroleum hydrocarbons into more bioavailable and biodegradable chemicals. However, previous research has shown that ozone can change the soil pH and create harmful organic compounds.
The research objective was to determine the short-term ecological toxicity of ozonation byproducts on seed germination of three distinct plant types (radish, lettuce, and grass) compared to untreated and uncontaminated soils. We hypothesize that the reduction of heavy hydrocarbon contamination in soil by ozone application will provide more suitable habitat for the germinating seeds. The effect of ozone treatment on seed germination and seedling quality was measured using ASTM standards for early seedling growth in conjunction with a gradient of potting soil amendments. Ozonation parameters were measured using established methods and include total petroleum hydrocarbons (TPH), dissolved organic carbon (DOC), and pH.
This study demonstrated the TPH levels fall up to 22% with ozonation, suggesting TPH removal is related to the amount of ozone delivered as opposed to the type of crude oil present. The DOC values increase comparably across crude oil types as the ozonation dose increases (from a background level of 0.25 g to 6.2 g/kg dry soil at the highest ozone level), suggesting that DOC production is directly related to the amount of ozone, not crude oil type. While ozonation reduced the mass of heavy hydrocarbons in the soil, it increased the amount of ozonation byproducts in the soil. For the three types of seeds used in the study, these changes in concentrations of TPH and DOC affected the species differently; however, no seed type showed improved germination after ozone treatment. Thus, ozone treatment by itself had a negative impact on germination potential.
Future research should focus on the effects of post-ozonation, long-term bioremediation on eco-toxicity. By helping define the eco-toxicity of ozonation techniques, this research can improve upon previously established ozone techniques for petroleum remediation and provide economic and environmental benefits when used for soil treatment.

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Created

Date Created
2020-05

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Voluntourism Participants' Attitude Toward the Environment, Culture, and Community

Description

Volunteering can lead to many positive outcomes on individuals in terms of social, psychological, and professional development. This study sought to understand the process and mindset of volunteers and how their experience affects attitudes towards environment. The purpose of this

Volunteering can lead to many positive outcomes on individuals in terms of social, psychological, and professional development. This study sought to understand the process and mindset of volunteers and how their experience affects attitudes towards environment. The purpose of this study is to analyze the attitude change of volunteers toward the environment, culture, and community after volunteering at a community of a background different than theirs. In this study, the volunteer setting is in Shonto, a Native American community in the Navajo Nation, Arizona. This study utilized a qualitative research approach. A total of 12 participants were interviewed in this study. All participants were members of Engineers Without Borders (EWB) at Arizona State University and have traveled to Shonto. Questions were asked to participants about their experiences with EWB and their volunteering experiences in Shonto. The main findings were categorized into four themes: 1) motivations; 2) preconceived perceptions and exposure; 3) collaboration and connection; and 4) commonality and reflection. The findings can be described as a process that participants go through in their entire volunteering experience. The first two themes occur before individuals volunteer and the last two themes occur after. First, individuals develop certain motivations to volunteer. Then, the preconceived perceptions of individuals were analyzed, and it was presumed that these perceptions were a result of their upbringing and exposure, or lack thereof, to the community they volunteer at. The last two themes occur after the individuals have volunteered. Individuals are able to collaborate and form a connection with the community, which influences their awareness and their ability to reflect on their experiences. These last two themes are important because they indicate the change of perceptions that volunteers perceive. These findings connect the motivations that volunteers have all the way to their attitude changes after volunteering. Further, findings demonstrate that the preconceived perceptions are influenced by an individual’s upbringing or exposure, but these misconceptions are changed after volunteering experience, which supports contact theory. Through these findings the study contributes to the existing literature on voluntourism. This study is applicable to organizations and tour operators who offer volunteer tourism programs and work with communities of different backgrounds. It can provide individuals an insight to other volunteering experiences.

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Date Created
2020-05

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Modernizing Structural Analysis and Design Education

Description

As structural engineers in practice continue to improve their methods and advance their analysis and design techniques through the use of new technology, how should structural engineering education programs evolve as well to match the increasing complexity of the industry?

As structural engineers in practice continue to improve their methods and advance their analysis and design techniques through the use of new technology, how should structural engineering education programs evolve as well to match the increasing complexity of the industry? This thesis serves to analyze the many differing opinions and techniques on modernizing structural engineering education programs through a literature review on the content put out by active structural engineering education reform committees, articles and publications by well-known educators and practitioners, and a series of interviews conducted with key individuals specifically for this project. According to the opinions analyzed in this paper, structural engineering education should be a 5-year program that ends with a master’s degree, so that students obtain enough necessary knowledge to begin their positions as structural engineers. Firms would rather continue the education of new-hires themselves after this time than to wait and pay more for students to finish longer graduate-type programs. Computer programs should be implemented further into education programs, and would be most productive not as a replacement to hand-calculation methods, but as a supplement. Students should be tasked with writing codes, so that they are required to implement these calculations into computer programs themselves, and use classical methods to verify their answers. In this way, engineering programs will be creating critical thinkers who can adapt to any new structural analysis and design programs, and not just be training students on current programs that will become obsolete with time. It is the responsibility of educators to educate current staff on how to implement these coding methods seamlessly into education as a supplement to hand calculation methods. Students will be able to learn what is behind commercial coding software, develop their hand-calculation skills through code verification, and focus more on the ever-important modeling and interpretation phases of problem solving. Practitioners will have the responsibility of not expecting students to graduate with knowledge of specific software programs, but instead recruiting students who showcase critical thinking skills and understand the backbone of these programs. They will continue the education of recent graduates themselves, providing them with real-world experience that they cannot receive in school while training them to use company-specific analysis and design software.

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Date Created
2020-05

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An Evaluation of Basic Oxygen Furnace Slag as Post-Treatment for Acid Rock Drainage

Description

Oxic beds containing basic oxygen furnace slag were evaluated as potential post-treatment method for sulfate reducing bioreactor (SRB) treatment of acid rock drainage. SRB effluent was pumped into BOF slag/sand leach beds, also known as oxic slag beds (OSBs), at

Oxic beds containing basic oxygen furnace slag were evaluated as potential post-treatment method for sulfate reducing bioreactor (SRB) treatment of acid rock drainage. SRB effluent was pumped into BOF slag/sand leach beds, also known as oxic slag beds (OSBs), at various flow rates. OSB influent versus effluent concentrations of dissolved metals (specifically magnesium and manganese) and water quality parameters (pH, dissolved oxygen concentration, and conductivity) were compared. The OSBs increased the pH of the SRB effluents from 6.2–6.7 to 7.5–8.3. Dissolved oxygen concentration increased from 2-4 mg L^(-1) to approximately 8 mg L^(-1). Conductivity remained similar, with some effluent values being less than influent. Manganese concentration was observed to be reduced through OSB post-treatment by an average of 8.2% reduction and a maximum of 23 % reduction. Magnesium was not reduced during OSB post-treatment. Other metal concentrations changes were analyzed. Recommendations the design of OSBs for future studies were made, and a proposed design was configured.

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Date Created
2020-05

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Effect of Drought Policies on Los Angeles Water Demand

Description

From 2007 to 2017, the state of California experienced two major droughts that required significant governmental action to decrease urban water demand. The purpose of this project is to isolate and explore the effects of these policy changes on water

From 2007 to 2017, the state of California experienced two major droughts that required significant governmental action to decrease urban water demand. The purpose of this project is to isolate and explore the effects of these policy changes on water use during and after these droughts, and to see how these policies interact with hydroclimatic variability. As explanatory variables in multiple linear regression (MLR) models, water use policies were found to be significant at both the zip code and city levels. Policies that specifically target behavioral changes were significant mathematical drivers of water use in city-level models. Policy data was aggregated into a timeline and coded based on categories including user type, whether the policy was voluntary or mandatory, the targeted water use type, and whether the change in question concerns active or passive conservation. The analyzed policies include but are not limited to state drought declarations, regulatory municipal ordinances, and incentive programs for household appliances. Spatial averages of available hydroclimatic data have been computed and validated using inverse distance weighting methods. The data was aggregated at the zip code level to be comparable to the available water use data for use in MLR models. Factors already known to affect water use, such as temperature, precipitation, income, and water stress, were brought into the MLR models as explanatory variables. After controlling for these factors, the timeline policies were brought into the model as coded variables to test their effect on water demand during the years 2000-2017. Clearly identifying which policy traits are effective will inform future policymaking in cities aiming to conserve water. The findings suggest that drought-related policies impact per capita urban water use. The results of the city level MLR models indicate that implementation of mandatory policies that target water use behaviors effectively reduce water use. Temperature, income, unemployment, and the WaSSI were also observed to be mathematical drivers of water use. Interaction effects between policies and the WaSSI were statistically significant at both model scales.

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Created

Date Created
2018-12

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Passive Thermosyphon Solar Water Heater for Existing Swimming Pool

Description

Water heaters that are manufactured for swimming pools come in several forms, most of which require an electrical input for a source of power. Passive-circulation systems, however, require no electrical power input because fluid circulation occurs as a result of

Water heaters that are manufactured for swimming pools come in several forms, most of which require an electrical input for a source of power. Passive-circulation systems, however, require no electrical power input because fluid circulation occurs as a result of thermal gradients. In solar-based systems, thermal gradients are developed by energy collected from sunlight. The combination of solar collection and passive circulation yields a system in which fluids, particularly water, are heated and circulated without need of assistance from external mechanical or electrical sources. The design of such a system was adapted from that of forced-circulation solar collector systems, as were the equations describing its thermodynamic properties. The design was developed based on such constraints as material corrosion resistance, overall system cost, and location-controlled size limitations. The thermodynamic description of the designed system was adjusted on the basis of the designed system’s physical aspects, such as the configuration and material of each component within the solar collector. Numerical analysis performed with the altered thermodynamic equations projected a total energy gain of 7.39 W between 9:00 and 10:00 A.M. and a total energy gain of 13.12 W between 4:00 and 5:00 P.M. The temperature of heated water exiting the collector system was projected to be 17.62°C in the morning and 25.56°C in the afternoon. The morning projection utilized an initial fluid temperature of 12°C and an ambient air temperature of 13°C, while the afternoon projection utilized an initial fluid temperature of 17°C and an ambient air temperature of 22°C. Field testing of the designed passive thermosyphon solar collector system was performed over a period of about one month with one temperature measurement taken at the collector outlet in the morning and another taken in the afternoon. For an ambient air temperature of 13°C, the linear regression developed from the morning dataset yielded an outlet water temperature of 20°C and that for the afternoon dataset yielded an outlet water temperature of 39°C for an ambient air temperature of 17°C. The percentage error between the projected and measured results was 13.51% for the morning period and 52.58% for the afternoon period. Numerical simulation and field data demonstrated that while the collector system operated successfully, its effects were limited to the volume of water immediately surrounding the outlet of the system; the rate of circulation within the system was too low for there to be a meaningful increase in the temperature of the water body at large. The stated results demonstrate that while the particular configuration of passive circulation solar collection technology developed in this instance is capable of transferring solar thermal energy to water without additional energy sources, significant modifications are necessary in order to improve the effectiveness of the technology. Such changes may come from improvements in material availability or alterations to the configuration of components of the collector system.

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Date Created
2021-05