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• 1. [Article] Wider Dissemination of Household Travel Survey Data Using Geographical Perturbation Methods

  Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which ...

  Citation × Citation Citation Abstract Copy Title: Wider Dissemination of Household Travel Survey Data Using Geographical Perturbation Methods Author: Clifton, Kelly J., Gehrke, Steven R. Year: 2014 Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which contribute to regional and statewide travel demand models. These data have utility beyond travel demand modeling in their application to transportation policy and travel behavior research. As the demand on these data increase, so have the quantity of information collected. Detailed geospatial referencing of the home, work and other travel destinations are common practice and permit the integration with other spatially archived data sources, such as land use characteristics, transportation system information, and other built environment, social and economic data. Other public agencies, private consultancies, non-profits and educational institutions may benefit from access to the original data with applications to areas such public health, equity, transportation safety and urban planning. Oregon Modeling Collaborative (OMC) has entered into an agreement with Oregon Modeling Steering Committee (OMSC) to host and make available Oregon Household Activity Survey (OHAS) datasets. But wide distribution of these important and expensive data is limited by the requirement to protect the confidentiality of survey participants, who are guaranteed anonymity in exchange for participation. Data are often aggregated to a geographic level such as Census tracts or transportation analysis zones (TAZs) before disseminating to the public, which limits the utility of this information. This project aims to develop a methodology to permit dissemination of these spatially-explicit data to a wider range of public constituents while at the same time, protecting the identities of study participants. Making use of these data, this project will use geographical perturbation methods to add noise to the original data to protect confidentiality while at the same time allowing the detailed geo-spatial referencing to be included in the disseminated data. The process includes: The coordinates (locations) will be geographically perturbed (masked) so that they do not reveal the identity of the traveler while at the same time retaining spatial relevance and resolution. Here the limits of the perturbation (minimum and maximum displacement) need to be determined that a) ensure confidentiality and b) minimize the errors introduced to the data. The original and perturbed (masked) data will be compared using various statistical approaches to develop a set of confidence measures for different types of transportation applications. For example, geographically perturbed (masked) may be more robust for automobile travel measures, such as vehicle miles traveled (VMT) or transit accessibility than for detailed pedestrian or bicycle trip attributes. This exercise will allow spatially-explicit OHAS data to be released to the public with some information about the confidence to which it can be applied. These data will be archived at Portland State University and made available to the public. The information and algorithms can be shared with other agencies collecting and archiving travel data, such as the National Household Travel Survey, metropolitan planning organizations and state departments of transportation, to permit wider dissemination of their data. Title: Wider Dissemination of Household Travel Survey Data Using Geographical Perturbation Methods Author: Clifton, Kelly J., Gehrke, Steven R. Year: 2014 Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which contribute to regional and statewide travel demand models. These data have utility beyond travel demand modeling in their application to transportation policy and travel behavior research. As the demand on these data increase, so have the quantity of information collected. Detailed geospatial referencing of the home, work and other travel destinations are common practice and permit the integration with other spatially archived data sources, such as land use characteristics, transportation system information, and other built environment, social and economic data. Other public agencies, private consultancies, non-profits and educational institutions may benefit from access to the original data with applications to areas such public health, equity, transportation safety and urban planning. Oregon Modeling Collaborative (OMC) has entered into an agreement with Oregon Modeling Steering Committee (OMSC) to host and make available Oregon Household Activity Survey (OHAS) datasets. But wide distribution of these important and expensive data is limited by the requirement to protect the confidentiality of survey participants, who are guaranteed anonymity in exchange for participation. Data are often aggregated to a geographic level such as Census tracts or transportation analysis zones (TAZs) before disseminating to the public, which limits the utility of this information. This project aims to develop a methodology to permit dissemination of these spatially-explicit data to a wider range of public constituents while at the same time, protecting the identities of study participants. Making use of these data, this project will use geographical perturbation methods to add noise to the original data to protect confidentiality while at the same time allowing the detailed geo-spatial referencing to be included in the disseminated data. The process includes: The coordinates (locations) will be geographically perturbed (masked) so that they do not reveal the identity of the traveler while at the same time retaining spatial relevance and resolution. Here the limits of the perturbation (minimum and maximum displacement) need to be determined that a) ensure confidentiality and b) minimize the errors introduced to the data. The original and perturbed (masked) data will be compared using various statistical approaches to develop a set of confidence measures for different types of transportation applications. For example, geographically perturbed (masked) may be more robust for automobile travel measures, such as vehicle miles traveled (VMT) or transit accessibility than for detailed pedestrian or bicycle trip attributes. This exercise will allow spatially-explicit OHAS data to be released to the public with some information about the confidence to which it can be applied. These data will be archived at Portland State University and made available to the public. The information and algorithms can be shared with other agencies collecting and archiving travel data, such as the National Household Travel Survey, metropolitan planning organizations and state departments of transportation, to permit wider dissemination of their data. Close

• 2. [Article] Development of a Pedestrian Demand Estimation Tool

  Most research on walking behavior has focused on mode choice or walk-trip frequency. In contrast, this study is one of the first to analyze the destination choice behaviors of pedestrians. Using about ...

  Citation × Citation Citation Abstract Copy Title: Development of a Pedestrian Demand Estimation Tool Author: Clifton, Kelly, Singleton, Patrick Allen, Muhs, Christopher D., Schneider, Robert J. Year: 2015 Most research on walking behavior has focused on mode choice or walk-trip frequency. In contrast, this study is one of the first to analyze the destination choice behaviors of pedestrians. Using about 4,500 walk trips from a 2011 household travel survey in the Portland, OR, region, we estimated multinomial logit pedestrian destination choice models for six trip purposes. Independent variables included terms for impedance (walk-trip distance); size (employment by type, households); supportive pedestrian environments (parks, a pedestrian index of the environment variable called PIE); barriers to walking (terrain, industrial-type employment); and traveler characteristics. Unique to this study was the use of small-scale destination zone alternatives. Distance was a significant deterrent to pedestrian destination choice, and people in carless or childless households were less sensitive to distance for some purposes. Employment (especially retail) was a strong attractor: doubling the number of jobs nearly doubled the odds of choosing a destination for home-based shopping walk trips. More attractive pedestrian environments were also positively associated with pedestrian destination choice after controlling for other factors. These results shed light on determinants of pedestrian destination choice behavior, and sensitivities in the models highlight potential policy-levers to increase walking activity. In addition, the destination choice models can be used in regional travel demand models or as pedestrian planning tools to evaluate land use and transportation policy and investment scenarios. Title: Development of a Pedestrian Demand Estimation Tool Author: Clifton, Kelly, Singleton, Patrick Allen, Muhs, Christopher D., Schneider, Robert J. Year: 2015 Most research on walking behavior has focused on mode choice or walk-trip frequency. In contrast, this study is one of the first to analyze the destination choice behaviors of pedestrians. Using about 4,500 walk trips from a 2011 household travel survey in the Portland, OR, region, we estimated multinomial logit pedestrian destination choice models for six trip purposes. Independent variables included terms for impedance (walk-trip distance); size (employment by type, households); supportive pedestrian environments (parks, a pedestrian index of the environment variable called PIE); barriers to walking (terrain, industrial-type employment); and traveler characteristics. Unique to this study was the use of small-scale destination zone alternatives. Distance was a significant deterrent to pedestrian destination choice, and people in carless or childless households were less sensitive to distance for some purposes. Employment (especially retail) was a strong attractor: doubling the number of jobs nearly doubled the odds of choosing a destination for home-based shopping walk trips. More attractive pedestrian environments were also positively associated with pedestrian destination choice after controlling for other factors. These results shed light on determinants of pedestrian destination choice behavior, and sensitivities in the models highlight potential policy-levers to increase walking activity. In addition, the destination choice models can be used in regional travel demand models or as pedestrian planning tools to evaluate land use and transportation policy and investment scenarios. Close

• 3. [Article] Isolated Water Circulation and Filtration System

  One big issue we are addressing is the large amount greywater produced by average households around the country. Still, the main problem is that, in areas affected by drought such as California, people ...

  Citation × Citation Citation Abstract Copy Title: Isolated Water Circulation and Filtration System Author: Gurganus, Adrik, Mwawai, Mellonie, Cedillo-Nielsen, Wysteria, Rekart, Morgan, Hoffman, Zander Year: 2016 One big issue we are addressing is the large amount greywater produced by average households around the country. Still, the main problem is that, in areas affected by drought such as California, people have little available clean water, and this system will greatly benefit these people directly. The Isolated water system uses a filtration combined of organic materials, soaps, dirt, foods and sink to filter out the grey used water. Since the water system is not connected with the local water system if there were a natural disaster the owner would have free access to a water source while the city water would be damaged and inaccessible. Title: Isolated Water Circulation and Filtration System Author: Gurganus, Adrik, Mwawai, Mellonie, Cedillo-Nielsen, Wysteria, Rekart, Morgan, Hoffman, Zander Year: 2016 One big issue we are addressing is the large amount greywater produced by average households around the country. Still, the main problem is that, in areas affected by drought such as California, people have little available clean water, and this system will greatly benefit these people directly. The Isolated water system uses a filtration combined of organic materials, soaps, dirt, foods and sink to filter out the grey used water. Since the water system is not connected with the local water system if there were a natural disaster the owner would have free access to a water source while the city water would be damaged and inaccessible. Close

• 4. [Article] Residential Greywater Recycling System

  In a typical household, a majority of the fresh water is utilized by the shower, bathroom sinks and laundry. Water exiting from these fixtures is considered greywater. This is wasteful because the greywater ...

  Citation × Citation Citation Abstract Copy Title: Residential Greywater Recycling System Author: Bui, Sophia, Clark, Clare, Hoang, Anthony, Le, Kim, Mishler, Skyler, Soler, Janette, Tran, Teresa Year: 2016 In a typical household, a majority of the fresh water is utilized by the shower, bathroom sinks and laundry. Water exiting from these fixtures is considered greywater. This is wasteful because the greywater is being combined with blackwater making it unusable. If greywater could be separated and captured, it can be reused for other purposes. We came to the conclusion that greywater is able to be recycled and reused for flushing excreta. Title: Residential Greywater Recycling System Author: Bui, Sophia, Clark, Clare, Hoang, Anthony, Le, Kim, Mishler, Skyler, Soler, Janette, Tran, Teresa Year: 2016 In a typical household, a majority of the fresh water is utilized by the shower, bathroom sinks and laundry. Water exiting from these fixtures is considered greywater. This is wasteful because the greywater is being combined with blackwater making it unusable. If greywater could be separated and captured, it can be reused for other purposes. We came to the conclusion that greywater is able to be recycled and reused for flushing excreta. Close

• 5. [Article] puddl: Gamifying Water Conservation

  As the global population surges, the demand for fresh water will only increase. With no technological breakthrough on the horizon, it is more important than ever to conserve water and not waste this precious ...

  Citation × Citation Citation Abstract Copy Title: puddl: Gamifying Water Conservation Author: Assenberg, Quince, Chen, Jack, Glenn, Denny, Lam, Jessica Year: 2016 As the global population surges, the demand for fresh water will only increase. With no technological breakthrough on the horizon, it is more important than ever to conserve water and not waste this precious resource. Water conservation is a serious issue, and will only become more severe as global warming worsens. As the global temperature increases, and rainfall becomes more sporadic, it will be important for communities to find new ways to save water. This push has already been made in certain areas in the united states, California, where they were forced to reduce their water consumption by 25%. Through our fieldwork and other research, we discovered three important factors that would shape our project. The first was all about flow! The flow in a sewage system is integral to its ability to function. If the flow of a sewage system gets too low, you encounter a number of logistical problems. Additionally, if you use too much water, you could adversely affect the ecosystems from which you took the water. Salmon, and their food chain, are affected the most by the overuse of water. When talking with Catherine Howells, we also learned about water conservation. Certain areas in the world, like Perth, Australia, are very good at conserving water, whereas other areas, like Phoenix, Arizona are not.. However, no matter where you are, it is very hard to conserve more than thirty percent of water usage. The average American family of four uses 400 gallons of water per day. On average, approximately 70 percent of that water is used indoors, with the bathroom being the largest consumer. This leaves a large amount of water to be conserve, especially when you consider the average Australian family of the same size uses on 238 gallons of water per day! Also, certain applications use a huge portion of a person’s daily water usage, for instance the toilet and washer equal forty‐eight percent of a household' water consumption, and by learning new ways to reduce this, families could save a lot of water! Title: puddl: Gamifying Water Conservation Author: Assenberg, Quince, Chen, Jack, Glenn, Denny, Lam, Jessica Year: 2016 As the global population surges, the demand for fresh water will only increase. With no technological breakthrough on the horizon, it is more important than ever to conserve water and not waste this precious resource. Water conservation is a serious issue, and will only become more severe as global warming worsens. As the global temperature increases, and rainfall becomes more sporadic, it will be important for communities to find new ways to save water. This push has already been made in certain areas in the united states, California, where they were forced to reduce their water consumption by 25%. Through our fieldwork and other research, we discovered three important factors that would shape our project. The first was all about flow! The flow in a sewage system is integral to its ability to function. If the flow of a sewage system gets too low, you encounter a number of logistical problems. Additionally, if you use too much water, you could adversely affect the ecosystems from which you took the water. Salmon, and their food chain, are affected the most by the overuse of water. When talking with Catherine Howells, we also learned about water conservation. Certain areas in the world, like Perth, Australia, are very good at conserving water, whereas other areas, like Phoenix, Arizona are not.. However, no matter where you are, it is very hard to conserve more than thirty percent of water usage. The average American family of four uses 400 gallons of water per day. On average, approximately 70 percent of that water is used indoors, with the bathroom being the largest consumer. This leaves a large amount of water to be conserve, especially when you consider the average Australian family of the same size uses on 238 gallons of water per day! Also, certain applications use a huge portion of a person’s daily water usage, for instance the toilet and washer equal forty‐eight percent of a household' water consumption, and by learning new ways to reduce this, families could save a lot of water! Close

• 6. [Article] véLo-CK

  Portland is known as Bike City U.S.A for its promotion of a eco friendly method of transportation and support of biking infrastructure. Although our city has this progressive reputation, there is a negative ...

  Citation × Citation Citation Abstract Copy Title: véLo-CK Author: Blakley, Anna, Cordisco, Jonathan, Huang, Jonathan, Huang, Justin, Perlman, Emma, Prasad, Ruhika, Suri, Siddarth, Swindell, Will Year: 2015 Portland is known as Bike City U.S.A for its promotion of a eco friendly method of transportation and support of biking infrastructure. Although our city has this progressive reputation, there is a negative aspect of a bike-loving city that has not received attention. The Oregon Household Activity survey in 2011 states that “about 29 percent of adults in Multnomah, Clackamas and Washington counties own a bike”. As more people has decided to commute with bikes, theft has increased dramatically. According to the Portland Police Bureau, “Portland thieves last year took more than 2,100 bikes worth well over $1 million combined”. In an attempt to solve this problem, the police bureau has proposed to create a task force to patrol areas of possible bike theft. Although this is a step in the right direction, it is not a realistic solution to this problem. The cost to employ more policemen to patrol the city would be high and most of these crimes are not prosecuted by in court. We talked to people who have experienced bike theft in Portland. Kimberly K said “I didn't understand how they could have stolen my bike because I had a cable lock. I was really angry and was afraid my insurance wouldn't pay for it.” John B said “I didn’t have enough money to buy a new bike and I didn’t buy bike insurance so I couldn’t buy a bike for over a year. Title: véLo-CK Author: Blakley, Anna, Cordisco, Jonathan, Huang, Jonathan, Huang, Justin, Perlman, Emma, Prasad, Ruhika, Suri, Siddarth, Swindell, Will Year: 2015 Portland is known as Bike City U.S.A for its promotion of a eco friendly method of transportation and support of biking infrastructure. Although our city has this progressive reputation, there is a negative aspect of a bike-loving city that has not received attention. The Oregon Household Activity survey in 2011 states that “about 29 percent of adults in Multnomah, Clackamas and Washington counties own a bike”. As more people has decided to commute with bikes, theft has increased dramatically. According to the Portland Police Bureau, “Portland thieves last year took more than 2,100 bikes worth well over $1 million combined”. In an attempt to solve this problem, the police bureau has proposed to create a task force to patrol areas of possible bike theft. Although this is a step in the right direction, it is not a realistic solution to this problem. The cost to employ more policemen to patrol the city would be high and most of these crimes are not prosecuted by in court. We talked to people who have experienced bike theft in Portland. Kimberly K said “I didn't understand how they could have stolen my bike because I had a cable lock. I was really angry and was afraid my insurance wouldn't pay for it.” John B said “I didn’t have enough money to buy a new bike and I didn’t buy bike insurance so I couldn’t buy a bike for over a year. Close

• 7. [Article] A Study on the Current State of Contaminants of Concern Research, With a Focus on Biosolids and Regulations

  Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport ...

  Citation × Citation Citation Abstract Copy Title: A Study on the Current State of Contaminants of Concern Research, With a Focus on Biosolids and Regulations Author: Fulton, Maren Year: 2016 Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport via stormwater runoff. Biosolids are composed of numerous constituents, with a number of environmentally persistent and potentially toxic contaminants of emerging concern identified as present in large concentrations. Research is needed to understand the transport and fate mechanisms of these compounds in biosolids. Additionally, this research is needed to determine a new priority framework to regulate CECs, both on the national level and regional levels. Wastewater treatment plant influent and effluent treatment regulations and practices may be improved upon as more knowledge accrues regarding contaminants of emerging concern behavior in the environment. The United States environmental regulatory process is a constant work in progress. Inherited from decades-old public health traditions, environmental regulatory programs arose to address the issues of public health as water and air quality issues surfaced. The Toxic Substances Control Act (TSCA) (15 U.S.C. 2601), enacted in 1976, provided the EPA regulatory authority to protect the environment and consumers’ health against risks posed by chemicals in commerce. TSCA only retroactively addressed chemical hazards, after they had been deemed unsafe and previously unrestricted in the public. A bill to overhaul TSCA, the Frank R. Lautenberg Chemical Safety for the 21st Century Act (House Amendment to the Senate Amendment to H.R. 2576, TSCA Modernization Act of 2015), was passed by the Senate on June 7, 2016 and sent on for President Obama’s signature. The amended law will give the EPA new authority to evaluate the safety of a new chemical before it enters the marketplace. It will also allow EPA to evaluate the safety of chemicals already known to be risks, including chemicals found to persist in the human body and in the environment. The Columbia River is presented as a case study as an example of a significant waterbody with research and regulatory gaps concerning CECs. The Columbia River waterbody was chosen as it represents an important natural resource for which data gaps exist on CEC sources and pathways into the waterbody, and which also does not receive adequate protective regulations under the national regulatory framework. Title: A Study on the Current State of Contaminants of Concern Research, With a Focus on Biosolids and Regulations Author: Fulton, Maren Year: 2016 Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport via stormwater runoff. Biosolids are composed of numerous constituents, with a number of environmentally persistent and potentially toxic contaminants of emerging concern identified as present in large concentrations. Research is needed to understand the transport and fate mechanisms of these compounds in biosolids. Additionally, this research is needed to determine a new priority framework to regulate CECs, both on the national level and regional levels. Wastewater treatment plant influent and effluent treatment regulations and practices may be improved upon as more knowledge accrues regarding contaminants of emerging concern behavior in the environment. The United States environmental regulatory process is a constant work in progress. Inherited from decades-old public health traditions, environmental regulatory programs arose to address the issues of public health as water and air quality issues surfaced. The Toxic Substances Control Act (TSCA) (15 U.S.C. 2601), enacted in 1976, provided the EPA regulatory authority to protect the environment and consumers’ health against risks posed by chemicals in commerce. TSCA only retroactively addressed chemical hazards, after they had been deemed unsafe and previously unrestricted in the public. A bill to overhaul TSCA, the Frank R. Lautenberg Chemical Safety for the 21st Century Act (House Amendment to the Senate Amendment to H.R. 2576, TSCA Modernization Act of 2015), was passed by the Senate on June 7, 2016 and sent on for President Obama’s signature. The amended law will give the EPA new authority to evaluate the safety of a new chemical before it enters the marketplace. It will also allow EPA to evaluate the safety of chemicals already known to be risks, including chemicals found to persist in the human body and in the environment. The Columbia River is presented as a case study as an example of a significant waterbody with research and regulatory gaps concerning CECs. The Columbia River waterbody was chosen as it represents an important natural resource for which data gaps exist on CEC sources and pathways into the waterbody, and which also does not receive adequate protective regulations under the national regulatory framework. Close