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• 1. [Article] Low Cost Air Quality Monitoring

  As sensor technology becomes more accessible, the development of low cost data collection systems is becoming more useful for both professional research and citizen science. This thesis explores the social ...

  Citation × Citation Citation Abstract Copy Title: Low Cost Air Quality Monitoring Author: Shang, Michelle G. Year: 2017 As sensor technology becomes more accessible, the development of low cost data collection systems is becoming more useful for both professional research and citizen science. This thesis explores the social and physical utility of low cost air monitoring (less than $200), and the design and implementation of a low cost sensor platform air monitoring system. Data is collected and analyzed from Ozone (O3), Carbon Monoxide (CO), Carbon Dioxide (CO2) and particulate matter (PM 2.5) sensors and compared with data from high accuracy instrumentation to assess the viability of using these low cost sensors for ambient air quality monitoring in research. The accuracy of these sensors varied greatly, but some sensors were accurate enough to gather quality lab data for a fraction of the cost of industry standard instruments. Title: Low Cost Air Quality Monitoring Author: Shang, Michelle G. Year: 2017 As sensor technology becomes more accessible, the development of low cost data collection systems is becoming more useful for both professional research and citizen science. This thesis explores the social and physical utility of low cost air monitoring (less than $200), and the design and implementation of a low cost sensor platform air monitoring system. Data is collected and analyzed from Ozone (O3), Carbon Monoxide (CO), Carbon Dioxide (CO2) and particulate matter (PM 2.5) sensors and compared with data from high accuracy instrumentation to assess the viability of using these low cost sensors for ambient air quality monitoring in research. The accuracy of these sensors varied greatly, but some sensors were accurate enough to gather quality lab data for a fraction of the cost of industry standard instruments. Close

• 2. [Article] Combining and Aggregating Environmental Data for Status and Trend Assessments: Challenges and Approaches

  Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess ...

  Citation × Citation Citation Abstract Copy Title: Combining and Aggregating Environmental Data for Status and Trend Assessments: Challenges and Approaches Author: Maas-Hebner, Kathleen G., Harte, Michael, Molina, Nancy, Hughes, Robert M., Schreck, Carl B., Yeakley, J. Alan Year: 2015 Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess local-, regional-, and landscape-level environmental conditions, particularly status and trends, and to improve their ability to make short-and long-term management decisions. Status monitoring assesses the current condition of a population or environmental condition across an area. Monitoring for trends aims at monitoring changes in populations or environmental condition through time. We wrote this paper to inform agency and nongovernmental organization managers, analysts, and consultants regarding the kinds of environmental data that can be combined with suitable techniques and statistically aggregated for new assessments. By doing so, they can increase the (1) use of available data and (2) the validity and reliability of the assessments. Increased awareness of the difficulties inherent in combining and aggregating data for local-and regional-level analyses can increase the likelihood that future monitoring efforts will be modified and/or planned to accommodate data from multiple sources. Title: Combining and Aggregating Environmental Data for Status and Trend Assessments: Challenges and Approaches Author: Maas-Hebner, Kathleen G., Harte, Michael, Molina, Nancy, Hughes, Robert M., Schreck, Carl B., Yeakley, J. Alan Year: 2015 Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess local-, regional-, and landscape-level environmental conditions, particularly status and trends, and to improve their ability to make short-and long-term management decisions. Status monitoring assesses the current condition of a population or environmental condition across an area. Monitoring for trends aims at monitoring changes in populations or environmental condition through time. We wrote this paper to inform agency and nongovernmental organization managers, analysts, and consultants regarding the kinds of environmental data that can be combined with suitable techniques and statistically aggregated for new assessments. By doing so, they can increase the (1) use of available data and (2) the validity and reliability of the assessments. Increased awareness of the difficulties inherent in combining and aggregating data for local-and regional-level analyses can increase the likelihood that future monitoring efforts will be modified and/or planned to accommodate data from multiple sources. Close

• 3. [Article] Acoustic Monitoring of Marine Conservation Areas

  This paper introduces underwater sensing technologies for acoustic monitoring of marine conservation areas. Small networks of individual passive acoustic sensors have been deployed to investigate a low-cost ...

  Citation × Citation Citation Abstract Copy Title: Acoustic Monitoring of Marine Conservation Areas Author: Zurk, Lisa, Ou, Helen, Schecklman, Scott, Lutwak, Ayal Year: 2014 This paper introduces underwater sensing technologies for acoustic monitoring of marine conservation areas. Small networks of individual passive acoustic sensors have been deployed to investigate a low-cost solution for monitoring motorized vessels and marine ambient noise in large areas. A data processing package, called “Conservancy-Watch,” is introduced for environmental management and conservation of natural resources. The package includes passive sensing database creation, ambient noise monitoring to identify long-term trends and impacts, classification of organic and boat vessel events, detection of marine mammals and estimation of their call density, and detection of motorized vessels. Test results on data collected at several conservation sites in Hawaii have confirmed the detection capability of individual hydrophone sensors. Title: Acoustic Monitoring of Marine Conservation Areas Author: Zurk, Lisa, Ou, Helen, Schecklman, Scott, Lutwak, Ayal Year: 2014 This paper introduces underwater sensing technologies for acoustic monitoring of marine conservation areas. Small networks of individual passive acoustic sensors have been deployed to investigate a low-cost solution for monitoring motorized vessels and marine ambient noise in large areas. A data processing package, called “Conservancy-Watch,” is introduced for environmental management and conservation of natural resources. The package includes passive sensing database creation, ambient noise monitoring to identify long-term trends and impacts, classification of organic and boat vessel events, detection of marine mammals and estimation of their call density, and detection of motorized vessels. Test results on data collected at several conservation sites in Hawaii have confirmed the detection capability of individual hydrophone sensors. Close

• 4. [Article] Development of a Knowledge-Based Scheduling and Quality Monitoring Software

  Here we detail the development of an intelligent scheduling and quality monitoring software package for a law firm. The scheduling aspect of the software forecasts preparation time of a batch of legal ...

  Citation × Citation Citation Abstract Copy Title: Development of a Knowledge-Based Scheduling and Quality Monitoring Software Author: Byrne, P. Year: 1993 Here we detail the development of an intelligent scheduling and quality monitoring software package for a law firm. The scheduling aspect of the software forecasts preparation time of a batch of legal documents. The quality monitoring aspect determines the probability that documents within batches will be returned for corrections. The software has been termed intelligent because the system updates its rules to reflect changes in the values of particular variables. Title: Development of a Knowledge-Based Scheduling and Quality Monitoring Software Author: Byrne, P. Year: 1993 Here we detail the development of an intelligent scheduling and quality monitoring software package for a law firm. The scheduling aspect of the software forecasts preparation time of a batch of legal documents. The quality monitoring aspect determines the probability that documents within batches will be returned for corrections. The software has been termed intelligent because the system updates its rules to reflect changes in the values of particular variables. Close

• 5. [Article] Risk-Based Monitoring: A Model and Application to FDA’s Imported Food Monitoring Program

  Regulatory agencies intervene in risky situations by outlawing practices that impose risks on society or by proscribing practices that reduce risk. Because public resources for enforcing regulation are ...

  Citation × Citation Citation Abstract Copy Title: Risk-Based Monitoring: A Model and Application to FDA’s Imported Food Monitoring Program Author: Martin, Sheila A., Beaulieu, Nancy Dean, Williams, Richard Year: 1999 Regulatory agencies intervene in risky situations by outlawing practices that impose risks on society or by proscribing practices that reduce risk. Because public resources for enforcing regulation are limited, public policy has recently emphasized maximizing the benefit from enforcement by considering the risk reduction achievable from each intervention. This emphasis requires a shift of resources to monitoring situations in which regulatory violations are most likely, their welfare effects are most serious, and their detection is probable and relatively inexpensive. This article is a risk-based monitoring model applied to the Food and Drug Administration's (FDA) import monitoring program. Although some components of the model are specific to FDA's data and regulatory needs, this model's basic structure is applicable to many situations in which a decisionmaker seeks to identify the most cost-effective choices for reducing risk. Title: Risk-Based Monitoring: A Model and Application to FDA’s Imported Food Monitoring Program Author: Martin, Sheila A., Beaulieu, Nancy Dean, Williams, Richard Year: 1999 Regulatory agencies intervene in risky situations by outlawing practices that impose risks on society or by proscribing practices that reduce risk. Because public resources for enforcing regulation are limited, public policy has recently emphasized maximizing the benefit from enforcement by considering the risk reduction achievable from each intervention. This emphasis requires a shift of resources to monitoring situations in which regulatory violations are most likely, their welfare effects are most serious, and their detection is probable and relatively inexpensive. This article is a risk-based monitoring model applied to the Food and Drug Administration's (FDA) import monitoring program. Although some components of the model are specific to FDA's data and regulatory needs, this model's basic structure is applicable to many situations in which a decisionmaker seeks to identify the most cost-effective choices for reducing risk. Close

• 6. [Article] Behavioral Reactivity Associated With Electronic Monitoring of Environmental Health Interventions-A Cluster Randomized Trial with Water Filters and Cookstoves

  Subject reactivity—when research participants change their behavior in response to being observed—has been documented showing the effect of human observers. Electronics sensors are increasingly used to ...

  Citation × Citation Citation Abstract Copy Title: Behavioral Reactivity Associated With Electronic Monitoring of Environmental Health Interventions-A Cluster Randomized Trial with Water Filters and Cookstoves Author: Thomas, Evan A., Tellez-Sanchez, Sarita, Wick, Carson, Kirby, Miles Year: 2016 Subject reactivity—when research participants change their behavior in response to being observed—has been documented showing the effect of human observers. Electronics sensors are increasingly used to monitor environmental health interventions, but the effect of sensors on behavior has not been assessed. We conducted a cluster randomized controlled trial in Rwanda among 170 households (70 blinded to the presence of the sensor, 100 open) testing whether awareness of an electronic monitor would result in a difference in weekly use of household water filters and improved cookstoves over a four-week surveillance period. A 63% increase in number of uses of the water filter per week between the groups was observed in week 1, an average of 4.4 times in the open group and 2.83 times in the blind group, declining in week 4 to an insignificant 55% difference of 2.82 uses in the open, and 1.93 in the blind. There were no significant differences in the number of stove uses per week between the two groups. For both filters and stoves, use decreased in both groups over four-week installation periods. This study suggests behavioral monitoring should attempt to account for reactivity to awareness of electronic monitors that persists for weeks or more. Title: Behavioral Reactivity Associated With Electronic Monitoring of Environmental Health Interventions-A Cluster Randomized Trial with Water Filters and Cookstoves Author: Thomas, Evan A., Tellez-Sanchez, Sarita, Wick, Carson, Kirby, Miles Year: 2016 Subject reactivity—when research participants change their behavior in response to being observed—has been documented showing the effect of human observers. Electronics sensors are increasingly used to monitor environmental health interventions, but the effect of sensors on behavior has not been assessed. We conducted a cluster randomized controlled trial in Rwanda among 170 households (70 blinded to the presence of the sensor, 100 open) testing whether awareness of an electronic monitor would result in a difference in weekly use of household water filters and improved cookstoves over a four-week surveillance period. A 63% increase in number of uses of the water filter per week between the groups was observed in week 1, an average of 4.4 times in the open group and 2.83 times in the blind group, declining in week 4 to an insignificant 55% difference of 2.82 uses in the open, and 1.93 in the blind. There were no significant differences in the number of stove uses per week between the two groups. For both filters and stoves, use decreased in both groups over four-week installation periods. This study suggests behavioral monitoring should attempt to account for reactivity to awareness of electronic monitors that persists for weeks or more. Close

• 7. [Article] A Strategy for Monitoring Glaciers

  Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Assessing and predicting the effect of glaciers on water resources require a monitoring ...

  Citation × Citation Citation Abstract Copy Title: A Strategy for Monitoring Glaciers Author: Fountain, Andrew G., Krimmel, Robert M., Trabant, Dennis C. Year: 1997 Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Assessing and predicting the effect of glaciers on water resources require a monitoring program to provide basic data for this understanding. The monitoring program of the U.S. Geological Survey employs a nested approach whereby an intensively studied glacier is surrounded by less intensively studied glaciers and those monitored solely by remote sensing. Ideally, each glacierized region of the United States would have such a network of glaciers. The intensively studied glacier provides a detailed understanding of the physical processes and their temporal changes that control the mass exchange of the glaciers in that region. The less intensively studied glaciers are used to assess the variability of such processes within the region. Title: A Strategy for Monitoring Glaciers Author: Fountain, Andrew G., Krimmel, Robert M., Trabant, Dennis C. Year: 1997 Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Assessing and predicting the effect of glaciers on water resources require a monitoring program to provide basic data for this understanding. The monitoring program of the U.S. Geological Survey employs a nested approach whereby an intensively studied glacier is surrounded by less intensively studied glaciers and those monitored solely by remote sensing. Ideally, each glacierized region of the United States would have such a network of glaciers. The intensively studied glacier provides a detailed understanding of the physical processes and their temporal changes that control the mass exchange of the glaciers in that region. The less intensively studied glaciers are used to assess the variability of such processes within the region. Close

• 8. [Article] Simultaneous Life Extension and Crack Monitoring of Fatigue-Damaged Steel Members Using Multifunctional Carbon Nanotube-Based Composites

  Steel structures including bridges are susceptible to cracking, particularly due to fatigue-sensitive details found in older designs. Therefore, one of the major challenges to keep those steel bridges ...

  Citation × Citation Citation Abstract Copy Title: Simultaneous Life Extension and Crack Monitoring of Fatigue-Damaged Steel Members Using Multifunctional Carbon Nanotube-Based Composites Author: Ahmed, Shafique, Schumacher, Thomas, Thostenson, Erik T., McConnell, Jennifer Year: 2017 Steel structures including bridges are susceptible to cracking, particularly due to fatigue-sensitive details found in older designs. Therefore, one of the major challenges to keep those steel bridges in service is to rehabilitate existing and potential fatigue damage. There are several conventional approaches to extend the fatigue-life of damaged steel members, e.g., drilling a crack stop-hole to reduce the stress concentration at the crack tip as well as welding and bolting of steel plates or adhesive-bonding of fiber-reinforced polymers (FRP) to reduce the overall stresses. Improvement in material properties of FRP and adhesives make them a viable candidate to apply for extending the fatigue-life of steel members. However, drawbacks include the potential for debonding of the adhesive layer and/or interfaces between adhesive and adherents as well as difficulty in monitoring fatigue crack growth after rehabilitation. In this research, a holistic approach is proposed and evaluated for simultaneous extension of fatigue-life and monitoring by integrating a carbon nanotube (CNT)-based sensing layer with an adhesively-bonded FRP reinforcement. CNT-based sensing layers have a nerve-like electric resistance network, which enables distributed sensing capabilities to monitor stress levels, crack growth, and damage progression. Using laboratory-scale experiments, the simultaneous fatigue-life extension and crack monitoring capability of multifunctional CNT-based composites was evaluated. This paper introduces the fundamental concept of integrated fatigue-rehabilitation and monitoring of steel members, presents a laboratory-scale experiment to demonstrate the feasibility and effectiveness, and discusses challenges for implementation in real structures.Title: Simultaneous Life Extension and Crack Monitoring of Fatigue-Damaged Steel Members Using Multifunctional Carbon Nanotube-Based Composites Title: Simultaneous Life Extension and Crack Monitoring of Fatigue-Damaged Steel Members Using Multifunctional Carbon Nanotube-Based Composites Author: Ahmed, Shafique, Schumacher, Thomas, Thostenson, Erik T., McConnell, Jennifer Year: 2017 Steel structures including bridges are susceptible to cracking, particularly due to fatigue-sensitive details found in older designs. Therefore, one of the major challenges to keep those steel bridges in service is to rehabilitate existing and potential fatigue damage. There are several conventional approaches to extend the fatigue-life of damaged steel members, e.g., drilling a crack stop-hole to reduce the stress concentration at the crack tip as well as welding and bolting of steel plates or adhesive-bonding of fiber-reinforced polymers (FRP) to reduce the overall stresses. Improvement in material properties of FRP and adhesives make them a viable candidate to apply for extending the fatigue-life of steel members. However, drawbacks include the potential for debonding of the adhesive layer and/or interfaces between adhesive and adherents as well as difficulty in monitoring fatigue crack growth after rehabilitation. In this research, a holistic approach is proposed and evaluated for simultaneous extension of fatigue-life and monitoring by integrating a carbon nanotube (CNT)-based sensing layer with an adhesively-bonded FRP reinforcement. CNT-based sensing layers have a nerve-like electric resistance network, which enables distributed sensing capabilities to monitor stress levels, crack growth, and damage progression. Using laboratory-scale experiments, the simultaneous fatigue-life extension and crack monitoring capability of multifunctional CNT-based composites was evaluated. This paper introduces the fundamental concept of integrated fatigue-rehabilitation and monitoring of steel members, presents a laboratory-scale experiment to demonstrate the feasibility and effectiveness, and discusses challenges for implementation in real structures.Title: Simultaneous Life Extension and Crack Monitoring of Fatigue-Damaged Steel Members Using Multifunctional Carbon Nanotube-Based Composites Close

• 9. [Article] Oregon Lake Watch, 2014 Annual Report

  The Oregon Lake Watch (OLW) volunteer monitoring program is now in its second year of operation, continuing its focus on early detection of aquatic invasive species (AIS), with a secondary focus on lake ...

  Citation × Citation Citation Abstract Copy Title: Oregon Lake Watch, 2014 Annual Report Author: Jordan, Meredith, Miller, Rich, Strecker, Angela L. Year: 2015 The Oregon Lake Watch (OLW) volunteer monitoring program is now in its second year of operation, continuing its focus on early detection of aquatic invasive species (AIS), with a secondary focus on lake water quality. The aquatic invasive species chosen as Watch List priorities for the OLW are based on the Oregon Department of Agriculture’s Noxious Weed List (Oregon Department of Agriculture Noxious Weed Control Program 2014) as well as professional judgement (more information can be found in Oregon Lake Watch Final Report 2014). This report summarizes the data collected by 15 of 24 OLW volunteers over 2014, across 110 sampling events and 20 Oregon lakes. Data collected by trained volunteers includes sightings of both native and aquatic invasive plants and animals, as well as recordings of lake temperature profiles, and Secchi depth, a measure of clarity. Of the 16 original water bodies surveyed in OLW’s first year (2013), 12 were surveyed again in 2014, and 8 are new waterbodies. Long-term monitoring of these lakes provides valuable information over time, and expanding the number of lakes monitored, especially in the case of monitoring for invasive species, means that more potentially harmful invasions can be stopped sooner. Ideally, the OLW will continue to monitor these current lakes, and expand their volunteer network to cover more waterbodies across Oregon as this program continues to grow. Title: Oregon Lake Watch, 2014 Annual Report Author: Jordan, Meredith, Miller, Rich, Strecker, Angela L. Year: 2015 The Oregon Lake Watch (OLW) volunteer monitoring program is now in its second year of operation, continuing its focus on early detection of aquatic invasive species (AIS), with a secondary focus on lake water quality. The aquatic invasive species chosen as Watch List priorities for the OLW are based on the Oregon Department of Agriculture’s Noxious Weed List (Oregon Department of Agriculture Noxious Weed Control Program 2014) as well as professional judgement (more information can be found in Oregon Lake Watch Final Report 2014). This report summarizes the data collected by 15 of 24 OLW volunteers over 2014, across 110 sampling events and 20 Oregon lakes. Data collected by trained volunteers includes sightings of both native and aquatic invasive plants and animals, as well as recordings of lake temperature profiles, and Secchi depth, a measure of clarity. Of the 16 original water bodies surveyed in OLW’s first year (2013), 12 were surveyed again in 2014, and 8 are new waterbodies. Long-term monitoring of these lakes provides valuable information over time, and expanding the number of lakes monitored, especially in the case of monitoring for invasive species, means that more potentially harmful invasions can be stopped sooner. Ideally, the OLW will continue to monitor these current lakes, and expand their volunteer network to cover more waterbodies across Oregon as this program continues to grow. Close

• 10. [Article] Event Detection Using Correlation within Arrays of Streaming PMU Data

  This thesis provides a synchrophasor data analysis methodology that leverages both statistical correlation techniques and a statistical distribution in order to identify data inconsistencies, as well as ...

  Citation × Citation Citation Abstract Copy Title: Event Detection Using Correlation within Arrays of Streaming PMU Data Author: Landford, Jordan Year: 2016 This thesis provides a synchrophasor data analysis methodology that leverages both statistical correlation techniques and a statistical distribution in order to identify data inconsistencies, as well as power system contingencies. This research utilizes archived Phasor Measurement Unit (PMU) data obtained from the Bonneville Power Administration in order to show that this methodology is not only feasible, but extremely useful for power systems monitoring, decision support, and planning purposes. By analyzing positive sequence voltage angles between a pair of PMUs at two different substation locations, an historic record of correlation is established. From this record, a Rayleigh distribution of correlation coefficients is calculated. The statistical parameters of this Rayleigh distribution are used to infer occurrences of power system and data events. To monitor an entire system, a simple solution would be observing each of these parameters for every PMU combination. One issue with this approach is that correlation of some PMU pairs may be redundant or yield little value to monitoring capabilities. Additionally, this approach quickly encounters scalability issues as each additional PMU adds considerably to computation - for example, if the system contains n PMUs the amount of computations will be n(n-1)/2. System-wide monitoring of these parameters in this fashion is cumbersome and inefficient. To address these issues, an alternative scheme is proposed which involves monitoring only a subset of PMUs characterized by electrically coupled zones, or clusters, of PMUs. These clusters include both electrically-distant and electrically-near PMU sites. When monitored over an event, these yield statistical parameters sufficient for detecting event occurrences. This clustering scheme can be utilized to significantly decrease computation time and allocation of resources while maintaining optimal system observability. Results from the statistical methods are presented for a select few case studies for both data and power system event detection. In addition, determination of cluster size and content is discussed in detail. Lastly, the viability of monitoring pertinent statistical parameters over various clustering schemes is demonstrated. Title: Event Detection Using Correlation within Arrays of Streaming PMU Data Author: Landford, Jordan Year: 2016 This thesis provides a synchrophasor data analysis methodology that leverages both statistical correlation techniques and a statistical distribution in order to identify data inconsistencies, as well as power system contingencies. This research utilizes archived Phasor Measurement Unit (PMU) data obtained from the Bonneville Power Administration in order to show that this methodology is not only feasible, but extremely useful for power systems monitoring, decision support, and planning purposes. By analyzing positive sequence voltage angles between a pair of PMUs at two different substation locations, an historic record of correlation is established. From this record, a Rayleigh distribution of correlation coefficients is calculated. The statistical parameters of this Rayleigh distribution are used to infer occurrences of power system and data events. To monitor an entire system, a simple solution would be observing each of these parameters for every PMU combination. One issue with this approach is that correlation of some PMU pairs may be redundant or yield little value to monitoring capabilities. Additionally, this approach quickly encounters scalability issues as each additional PMU adds considerably to computation - for example, if the system contains n PMUs the amount of computations will be n(n-1)/2. System-wide monitoring of these parameters in this fashion is cumbersome and inefficient. To address these issues, an alternative scheme is proposed which involves monitoring only a subset of PMUs characterized by electrically coupled zones, or clusters, of PMUs. These clusters include both electrically-distant and electrically-near PMU sites. When monitored over an event, these yield statistical parameters sufficient for detecting event occurrences. This clustering scheme can be utilized to significantly decrease computation time and allocation of resources while maintaining optimal system observability. Results from the statistical methods are presented for a select few case studies for both data and power system event detection. In addition, determination of cluster size and content is discussed in detail. Lastly, the viability of monitoring pertinent statistical parameters over various clustering schemes is demonstrated. Close