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• 31. [Article] Using Landsat TM Imagery to Monitor Vegetation Change Following Flow Restoration to the Lower Owens River, California

  Rehabilitating river corridors to restore valuable riparian habitat consumes significant resources from both governments and private companies. Given these considerable expenditures, it is important to ...

  Citation × Citation Citation Abstract Copy Title: Using Landsat TM Imagery to Monitor Vegetation Change Following Flow Restoration to the Lower Owens River, California Author: Bross, Lesley Crandell Year: 2015 Rehabilitating river corridors to restore valuable riparian habitat consumes significant resources from both governments and private companies. Given these considerable expenditures, it is important to monitor the progress of such projects. This study evaluated the utility of using Landsat Thematic Mapper remotely-sensed data from 2002 and 2009 to monitor vegetation change induced by instream flow restoration to the Lower Owens River in central California. This study compared the results of an unsupervised classification with an NDVI threshold classification to appraise the resources required and effectiveness of each analysis method. The results were inspected by creating standard remote sensing accuracy error matrices and by correlating landscape pattern metrics with bird indicator species. Both sets of classified maps show a noticeable increase in riparian vegetation in the study area following flow restoration in 2006, indicating an improvement of the quality of bird habitat. The study concluded that analyzing vegetation change using the unsupervised classification technique required more effort, expert knowledge, and supplementary data than using the NDVI threshold method. If these prerequisites are met, the output from the unsupervised classification process produces a more precise map of land cover change than the NDVI threshold method. However, if an analyst is lacking either resources or ground verification data, the NDVI threshold technique is capable of providing a generalized, but still valid evaluation of vegetation change. This conclusion is supported by higher correlations between indicator bird species under the unsupervised classification method than were found with the NDVI threshold method. Title: Using Landsat TM Imagery to Monitor Vegetation Change Following Flow Restoration to the Lower Owens River, California Author: Bross, Lesley Crandell Year: 2015 Rehabilitating river corridors to restore valuable riparian habitat consumes significant resources from both governments and private companies. Given these considerable expenditures, it is important to monitor the progress of such projects. This study evaluated the utility of using Landsat Thematic Mapper remotely-sensed data from 2002 and 2009 to monitor vegetation change induced by instream flow restoration to the Lower Owens River in central California. This study compared the results of an unsupervised classification with an NDVI threshold classification to appraise the resources required and effectiveness of each analysis method. The results were inspected by creating standard remote sensing accuracy error matrices and by correlating landscape pattern metrics with bird indicator species. Both sets of classified maps show a noticeable increase in riparian vegetation in the study area following flow restoration in 2006, indicating an improvement of the quality of bird habitat. The study concluded that analyzing vegetation change using the unsupervised classification technique required more effort, expert knowledge, and supplementary data than using the NDVI threshold method. If these prerequisites are met, the output from the unsupervised classification process produces a more precise map of land cover change than the NDVI threshold method. However, if an analyst is lacking either resources or ground verification data, the NDVI threshold technique is capable of providing a generalized, but still valid evaluation of vegetation change. This conclusion is supported by higher correlations between indicator bird species under the unsupervised classification method than were found with the NDVI threshold method. Close

• 32. [Article] The Value of Long-Term Stream Invertebrate Data Collected by Citizen Scientists

  The purpose of this investigation was to systematically examine the variability associated with temporally-oriented invertebrate data collected by citizen scientists and consider the value of such data ...

  Citation × Citation Citation Abstract Copy Title: The Value of Long-Term Stream Invertebrate Data Collected by Citizen Scientists Author: Edwards, Patrick Michael Year: 2016 The purpose of this investigation was to systematically examine the variability associated with temporally-oriented invertebrate data collected by citizen scientists and consider the value of such data for use in stream management. Variability in invertebrate data was estimated for three sources of variation: sampling, within-reach spatial and long-term temporal. Long-term temporal data were also evaluated using ordinations and an Index of Biotic Integrity (IBI). Through two separate investigations over an 11-year study period, participants collected more than 400 within-reach samples during 44 sampling events at three streams in the western United States. Within-reach invertebrate abundance coefficient of variation (CV) ranged from 0.44–0.50 with approximately 62% of the observed variation strictly due to sampling. Long-term temporal CV ranged from 0.31–0.36 with 27–30% of the observed variation in invertebrate abundance related to climate conditions (El Niño strength) and sampling year. Ordinations showed that citizen-generated assemblage data could reliably detect differences between study streams and seasons. IBI scores were significantly different between streams but not seasons. The findings of this study suggest that citizen data would likely detect a change in mean invertebrate density greater than 50% and would also be useful for monitoring changes in assemblage. The information presented here will help stream managers interpret and evaluate changes to the stream invertebrate community detected by citizen-based programs. Title: The Value of Long-Term Stream Invertebrate Data Collected by Citizen Scientists Author: Edwards, Patrick Michael Year: 2016 The purpose of this investigation was to systematically examine the variability associated with temporally-oriented invertebrate data collected by citizen scientists and consider the value of such data for use in stream management. Variability in invertebrate data was estimated for three sources of variation: sampling, within-reach spatial and long-term temporal. Long-term temporal data were also evaluated using ordinations and an Index of Biotic Integrity (IBI). Through two separate investigations over an 11-year study period, participants collected more than 400 within-reach samples during 44 sampling events at three streams in the western United States. Within-reach invertebrate abundance coefficient of variation (CV) ranged from 0.44–0.50 with approximately 62% of the observed variation strictly due to sampling. Long-term temporal CV ranged from 0.31–0.36 with 27–30% of the observed variation in invertebrate abundance related to climate conditions (El Niño strength) and sampling year. Ordinations showed that citizen-generated assemblage data could reliably detect differences between study streams and seasons. IBI scores were significantly different between streams but not seasons. The findings of this study suggest that citizen data would likely detect a change in mean invertebrate density greater than 50% and would also be useful for monitoring changes in assemblage. The information presented here will help stream managers interpret and evaluate changes to the stream invertebrate community detected by citizen-based programs. Close

• 33. [Article] From Drought Monitoring to Forecasting: a Combined Dynamical-Statistical Modeling Framework

  Drought is the most costly hazard among all natural disasters. Despite the significant improvements in drought modeling over the last decade, accurate provisions of drought conditions in a timely manner ...

  Citation × Citation Citation Abstract Copy Title: From Drought Monitoring to Forecasting: a Combined Dynamical-Statistical Modeling Framework Author: Yan, Hongxiang Year: 2016 Drought is the most costly hazard among all natural disasters. Despite the significant improvements in drought modeling over the last decade, accurate provisions of drought conditions in a timely manner is still one of the major research challenges. In order to improve the current drought monitoring and forecasting skills, this study presents a hybrid system with a combination of remotely sensed data assimilation based on particle filtering and a probabilistic drought forecasting model. Besides the proposed drought monitoring system through land data assimilation, another novel aspect of this dissertation is to seek the use of data assimilation to quantify land initial condition uncertainty rather than relying entirely on the hydrologic model or the land surface model to generate a single deterministic initial condition. Monthly to seasonal drought forecasting products are generated using the updated initial conditions. The computational complexity of the distributed data assimilation system required a modular parallel particle filtering framework which was developed and allowed for a large ensemble size in particle filtering implementation. The application of the proposed system is demonstrated with two case studies at the regional (Columbia River Basin) and the Conterminous United States. Results from both synthetic and real case studies suggest that the land data assimilation system significantly improves drought monitoring and forecasting skills. These results also show how sensitive the seasonal drought forecasting skill is to the initial conditions, which can lead to better facilitation of the state/federal drought preparation and response actions. Title: From Drought Monitoring to Forecasting: a Combined Dynamical-Statistical Modeling Framework Author: Yan, Hongxiang Year: 2016 Drought is the most costly hazard among all natural disasters. Despite the significant improvements in drought modeling over the last decade, accurate provisions of drought conditions in a timely manner is still one of the major research challenges. In order to improve the current drought monitoring and forecasting skills, this study presents a hybrid system with a combination of remotely sensed data assimilation based on particle filtering and a probabilistic drought forecasting model. Besides the proposed drought monitoring system through land data assimilation, another novel aspect of this dissertation is to seek the use of data assimilation to quantify land initial condition uncertainty rather than relying entirely on the hydrologic model or the land surface model to generate a single deterministic initial condition. Monthly to seasonal drought forecasting products are generated using the updated initial conditions. The computational complexity of the distributed data assimilation system required a modular parallel particle filtering framework which was developed and allowed for a large ensemble size in particle filtering implementation. The application of the proposed system is demonstrated with two case studies at the regional (Columbia River Basin) and the Conterminous United States. Results from both synthetic and real case studies suggest that the land data assimilation system significantly improves drought monitoring and forecasting skills. These results also show how sensitive the seasonal drought forecasting skill is to the initial conditions, which can lead to better facilitation of the state/federal drought preparation and response actions. Close

• 34. [Article] Performance and Application of an Inexpensive Method for Measurement of Nitrogen Dioxide

  To make air quality monitoring accessible to a broad range of people (i.e. consumers, educational groups, and environmental activist) a low-cost method for sampling nitrogen dioxide (NO₂) was modeled after ...

  Citation × Citation Citation Abstract Copy Title: Performance and Application of an Inexpensive Method for Measurement of Nitrogen Dioxide Author: Parra, Jeremy Year: 2013 To make air quality monitoring accessible to a broad range of people (i.e. consumers, educational groups, and environmental activist) a low-cost method for sampling nitrogen dioxide (NO₂) was modeled after the Palmes and Gunnison diffusion samplers. This article describes the results of using cost-effective passive diffusion tubes for measuring NO₂ in outdoor environments. Samplers are compared against a collocated chemiluminescence (active) monitor in a gas exposure chamber for concentration of NO₂ between 10 and 200 ppb/v (parts per billion per volume). In these calibration experiments diffusion samplers had strong correlation to the active monitor, R2 = 0.94 for a one week sample interval, and a R2 = 0.91 for a two week sample interval. A four week study was conducted with a collocated active monitor and a total of 42 samplers. The samplers were divided into 6 groups and exposed in one week and two week intervals under environmental conditions: temperature 18 - 31°C, relative humidity 27 - 57 %, wind speed 0.4 - 3 m/s, and NO₂ concentration 2 - 22 ppb/v. The precision, calculated as the relative standard deviation, for the one week sample interval was found to be 8.2%, and for the two week sample interval 20.2%. Three cleaning methods of exposed samplers are compared in order to identify bias in reusing components. Using the best cleaning method the mean NO₂ absorbance of a dry sampler is 1.3 ± 0.4 ppb/v as opposed to a zero absorbance for unused samplers. Faculty Mentor: Linda George Title: Performance and Application of an Inexpensive Method for Measurement of Nitrogen Dioxide Author: Parra, Jeremy Year: 2013 To make air quality monitoring accessible to a broad range of people (i.e. consumers, educational groups, and environmental activist) a low-cost method for sampling nitrogen dioxide (NO₂) was modeled after the Palmes and Gunnison diffusion samplers. This article describes the results of using cost-effective passive diffusion tubes for measuring NO₂ in outdoor environments. Samplers are compared against a collocated chemiluminescence (active) monitor in a gas exposure chamber for concentration of NO₂ between 10 and 200 ppb/v (parts per billion per volume). In these calibration experiments diffusion samplers had strong correlation to the active monitor, R2 = 0.94 for a one week sample interval, and a R2 = 0.91 for a two week sample interval. A four week study was conducted with a collocated active monitor and a total of 42 samplers. The samplers were divided into 6 groups and exposed in one week and two week intervals under environmental conditions: temperature 18 - 31°C, relative humidity 27 - 57 %, wind speed 0.4 - 3 m/s, and NO₂ concentration 2 - 22 ppb/v. The precision, calculated as the relative standard deviation, for the one week sample interval was found to be 8.2%, and for the two week sample interval 20.2%. Three cleaning methods of exposed samplers are compared in order to identify bias in reusing components. Using the best cleaning method the mean NO₂ absorbance of a dry sampler is 1.3 ± 0.4 ppb/v as opposed to a zero absorbance for unused samplers. Faculty Mentor: Linda George Close

• 35. [Article] Algorithm for Premature Ventricular Contraction Detection from a Subcutaneous Electrocardiogram Signal

  Cardiac arrhythmias occur when the normal pattern of electrical signals in the heart breaks down. A premature ventricular contraction (PVC) is a common type of arrhythmia that occurs when a heartbeat originates ...

  Citation × Citation Citation Abstract Copy Title: Algorithm for Premature Ventricular Contraction Detection from a Subcutaneous Electrocardiogram Signal Author: Shelly, Iris Lynn Year: 2016 Cardiac arrhythmias occur when the normal pattern of electrical signals in the heart breaks down. A premature ventricular contraction (PVC) is a common type of arrhythmia that occurs when a heartbeat originates from an ectopic focus within the ventricles rather than from the sinus node in the right atrium. This and other arrhythmias are often diagnosed with the help of an electrocardiogram, or ECG, which records the electrical activity of the heart using electrodes placed on the skin. In an ECG signal, a PVC is characterized by both timing and morphological differences from a normal sinus beat. An implantable cardiac monitor (ICM) is a device used to help physicians diagnose and monitor infrequent cardiac arrhythmias that may not be observed during an ECG recording performed during a normal clinic visit. These devices are implanted under the skin of the chest and simply monitor and record the electrical activity of the heart. The recorded signal is referred to as a subcutaneous electrocardiogram, or SECG. This thesis proposes and tests a novel algorithm that uses an SECG signal to perform PVC detection and is suitable for implementation within an implantable cardiac monitoring device. The proposed algorithm uses a combination of morphological and timing criteria to identify PVCs in near real time. Current commercially-available ICMs do not provide a PVC detection feature, so the proposed algorithm could help provide physicians with valuable additional diagnostic information about a clinically-significant arrhythmia. Title: Algorithm for Premature Ventricular Contraction Detection from a Subcutaneous Electrocardiogram Signal Author: Shelly, Iris Lynn Year: 2016 Cardiac arrhythmias occur when the normal pattern of electrical signals in the heart breaks down. A premature ventricular contraction (PVC) is a common type of arrhythmia that occurs when a heartbeat originates from an ectopic focus within the ventricles rather than from the sinus node in the right atrium. This and other arrhythmias are often diagnosed with the help of an electrocardiogram, or ECG, which records the electrical activity of the heart using electrodes placed on the skin. In an ECG signal, a PVC is characterized by both timing and morphological differences from a normal sinus beat. An implantable cardiac monitor (ICM) is a device used to help physicians diagnose and monitor infrequent cardiac arrhythmias that may not be observed during an ECG recording performed during a normal clinic visit. These devices are implanted under the skin of the chest and simply monitor and record the electrical activity of the heart. The recorded signal is referred to as a subcutaneous electrocardiogram, or SECG. This thesis proposes and tests a novel algorithm that uses an SECG signal to perform PVC detection and is suitable for implementation within an implantable cardiac monitoring device. The proposed algorithm uses a combination of morphological and timing criteria to identify PVCs in near real time. Current commercially-available ICMs do not provide a PVC detection feature, so the proposed algorithm could help provide physicians with valuable additional diagnostic information about a clinically-significant arrhythmia. Close

• 36. [Article] Solving Chemical Problems of Environmental Importance Using Cavity Ring-Down Spectroscopy

  Cavity ring-down (CRD) is a sensitive variant of traditional absorption spectroscopy that has found increasing use in a number of chemical measurement applications. This review focuses on applications ...

  Citation × Citation Citation Abstract Copy Title: Solving Chemical Problems of Environmental Importance Using Cavity Ring-Down Spectroscopy Author: Atkinson, Dean B. Year: 2003 Cavity ring-down (CRD) is a sensitive variant of traditional absorption spectroscopy that has found increasing use in a number of chemical measurement applications. This review focuses on applications of cavity ring-down spectroscopy that will be of interest to environmental chemists and analytical chemists working on environmental problems. The applications are classified into direct monitoring approaches, indirect analysis methods and ancillary studies and a differentiation is made between field-tested instruments and proof of principle studies. Title: Solving Chemical Problems of Environmental Importance Using Cavity Ring-Down Spectroscopy Author: Atkinson, Dean B. Year: 2003 Cavity ring-down (CRD) is a sensitive variant of traditional absorption spectroscopy that has found increasing use in a number of chemical measurement applications. This review focuses on applications of cavity ring-down spectroscopy that will be of interest to environmental chemists and analytical chemists working on environmental problems. The applications are classified into direct monitoring approaches, indirect analysis methods and ancillary studies and a differentiation is made between field-tested instruments and proof of principle studies. Close

• 37. [Article] Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012

  Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012 Author: Miller, Rich, Sytsma, Mark D. Year: 2013 Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were collected using plant rakes, benthic dredges, plankton nets, and crayfish traps. No invasive aquatic plants, gastropods, snails, bivalves or crayfish were detected in the lakes. Title: Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012 Author: Miller, Rich, Sytsma, Mark D. Year: 2013 Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were collected using plant rakes, benthic dredges, plankton nets, and crayfish traps. No invasive aquatic plants, gastropods, snails, bivalves or crayfish were detected in the lakes. Close

• 38. [Article] Spatial patterns of air toxins in the region

  This Atlas draws on the Portland Air Toxics Assessment (PATA) study to explore the regional variation of air quality. The PATA study presents an extraordinary opportunity to think about how the creation ...

  Citation × Citation Citation Abstract Copy Title: Spatial patterns of air toxins in the region Author: George, Linda Acha, Shandas, Vivek Year: 2009 This Atlas draws on the Portland Air Toxics Assessment (PATA) study to explore the regional variation of air quality. The PATA study presents an extraordinary opportunity to think about how the creation of new information can help us better plan our cities, but it also challenges us to think about the impacts of the choices we make. Title: Spatial patterns of air toxins in the region Author: George, Linda Acha, Shandas, Vivek Year: 2009 This Atlas draws on the Portland Air Toxics Assessment (PATA) study to explore the regional variation of air quality. The PATA study presents an extraordinary opportunity to think about how the creation of new information can help us better plan our cities, but it also challenges us to think about the impacts of the choices we make. Close

• 39. [Article] Comparative self-monitoring behavior and recall of verbal and nonverbal interactional information about partner in conversations with ablebodied and disabled partners

  When strangers meet, there is a high level of uncertainty due to the infinite number of possible alternatives in behavior between the two people. Previous research indicates that communicators will attempt ...

  Citation × Citation Citation Abstract Copy Title: Comparative self-monitoring behavior and recall of verbal and nonverbal interactional information about partner in conversations with ablebodied and disabled partners Author: Werkman, Doris L. Year: 1986 When strangers meet, there is a high level of uncertainty due to the infinite number of possible alternatives in behavior between the two people. Previous research indicates that communicators will attempt to reduce the level of uncertainty by using available verbal and nonverbal information of the other, by seeking similarities with the other, and by observing the situation itself. This information is used to predict attitudes and beliefs, as well as to attribute characteristics of the other. Other studies indicate that a person will increase her level of self-monitoring activity when the level of uncertainty is increased. Title: Comparative self-monitoring behavior and recall of verbal and nonverbal interactional information about partner in conversations with ablebodied and disabled partners Author: Werkman, Doris L. Year: 1986 When strangers meet, there is a high level of uncertainty due to the infinite number of possible alternatives in behavior between the two people. Previous research indicates that communicators will attempt to reduce the level of uncertainty by using available verbal and nonverbal information of the other, by seeking similarities with the other, and by observing the situation itself. This information is used to predict attitudes and beliefs, as well as to attribute characteristics of the other. Other studies indicate that a person will increase her level of self-monitoring activity when the level of uncertainty is increased. Close

• 40. [Article] System Engineering in Health Care System: A Case Study for Self-Monitoring Technology, Diabetes

  This paper aims to spot areas that policy should focus on in order to have a healthy ecosystem for the current and potential diabetic people in U.S by implementing a roadmapping analysis to 15 years ...

  Citation × Citation Citation Abstract Copy Title: System Engineering in Health Care System: A Case Study for Self-Monitoring Technology, Diabetes Author: Alswine, Nouf, Alkharboosh, Haitham Year: 2017 This paper aims to spot areas that policy should focus on in order to have a healthy ecosystem for the current and potential diabetic people in U.S by implementing a roadmapping analysis to 15 years from now. It examines several drivers involved in societal issue that technological capability can solve. Also, system engineering view used to cover several interconnected aspect to this social problem. The paper uses a self-monitoring technology as a case study to examine this issues Title: System Engineering in Health Care System: A Case Study for Self-Monitoring Technology, Diabetes Author: Alswine, Nouf, Alkharboosh, Haitham Year: 2017 This paper aims to spot areas that policy should focus on in order to have a healthy ecosystem for the current and potential diabetic people in U.S by implementing a roadmapping analysis to 15 years from now. It examines several drivers involved in societal issue that technological capability can solve. Also, system engineering view used to cover several interconnected aspect to this social problem. The paper uses a self-monitoring technology as a case study to examine this issues Close