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• 41. [Article] Waterfall Lasers

  Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated ...

  Citation × Citation Citation Abstract Copy Title: Waterfall Lasers Author: Casperson, Lee W. Year: 1997 Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated with fountains, dams, and natural waterfalls. In many respects these fluid feedback oscillations are similar to the electromagnetic modes of typical lasers, and recognition of this similarity led to the interpretation of the waterfall behavior. Gain profiles for the waterfall oscillations are developed, and the relationship of experimental waterfall data to the laser-like models is considered in detail. Title: Waterfall Lasers Author: Casperson, Lee W. Year: 1997 Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated with fountains, dams, and natural waterfalls. In many respects these fluid feedback oscillations are similar to the electromagnetic modes of typical lasers, and recognition of this similarity led to the interpretation of the waterfall behavior. Gain profiles for the waterfall oscillations are developed, and the relationship of experimental waterfall data to the laser-like models is considered in detail. Close

• 42. [Article] Fluttering Fountains: Annular Geometry

  Under certain conditions of flow rate, height, and feedback, periodic or chaotic fluttering oscillations can be observed as the sheet of water from a dam or waterfall fountain descends through the air. ...

  Citation × Citation Citation Abstract Copy Title: Fluttering Fountains: Annular Geometry Author: Casperson, Lee W. Year: 1995 Under certain conditions of flow rate, height, and feedback, periodic or chaotic fluttering oscillations can be observed as the sheet of water from a dam or waterfall fountain descends through the air. Numerical and analytical interpretations of this phenomenon have recently been reported. The extension of these results to other fountain geometries is discussed here together with experimental observations on an annular waterfall fountain. Title: Fluttering Fountains: Annular Geometry Author: Casperson, Lee W. Year: 1995 Under certain conditions of flow rate, height, and feedback, periodic or chaotic fluttering oscillations can be observed as the sheet of water from a dam or waterfall fountain descends through the air. Numerical and analytical interpretations of this phenomenon have recently been reported. The extension of these results to other fountain geometries is discussed here together with experimental observations on an annular waterfall fountain. Close

• 43. [Article] Migration Movement

  All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements ...

  Citation × Citation Citation Abstract Copy Title: Migration Movement Author: Porte, Robert Year: 2016 All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements of their citizens, they end up doing the work of a dam, they generate power and control floods, but in doing so they destroy life and wreck the surrounding space." Justseeds†(excerpt) As the current administration at the time of this writing continues its program of deportation of women and children from the U.S. to their war torn and violent countries of origin, I want not to engage in an art practice that doesn’t consider the sociopolitical climate of our times. Title: Migration Movement Author: Porte, Robert Year: 2016 All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements of their citizens, they end up doing the work of a dam, they generate power and control floods, but in doing so they destroy life and wreck the surrounding space." Justseeds†(excerpt) As the current administration at the time of this writing continues its program of deportation of women and children from the U.S. to their war torn and violent countries of origin, I want not to engage in an art practice that doesn’t consider the sociopolitical climate of our times. Close

• 44. [Article] Curbing Teen Dating Violence: Evidence from a School Prevention Program

  This research brief summarizes a survey about the effectiveness of programs from Break the Cycle, a nonprofit organization dedicated to developing and fielding dating-violence prevention programs.

  Citation × Citation Citation Abstract Copy Title: Curbing Teen Dating Violence: Evidence from a School Prevention Program Author: Jaycox, Lisa, McCaffrey, Daniel F., Weidmer, Beverly A., Marshall, Grant N., Collins, Rebecca L., Hickman, Laura J., Quigley, Denise D. Year: 2006 This research brief summarizes a survey about the effectiveness of programs from Break the Cycle, a nonprofit organization dedicated to developing and fielding dating-violence prevention programs. Title: Curbing Teen Dating Violence: Evidence from a School Prevention Program Author: Jaycox, Lisa, McCaffrey, Daniel F., Weidmer, Beverly A., Marshall, Grant N., Collins, Rebecca L., Hickman, Laura J., Quigley, Denise D. Year: 2006 This research brief summarizes a survey about the effectiveness of programs from Break the Cycle, a nonprofit organization dedicated to developing and fielding dating-violence prevention programs. Close

• 45. [Article] Formalizing Collaboration: Establishing Domestic Violence Memorandums of Understanding Between Military Installations and Civilian Communities

  The military has begun to encourage collaborative relationships--through formal memorandums of understanding (MOUs)--between military installations and neighboring communities intended to prevent and respond ...

  Citation × Citation Citation Abstract Copy Title: Formalizing Collaboration: Establishing Domestic Violence Memorandums of Understanding Between Military Installations and Civilian Communities Author: Hickman, Laura J., Davis, Lois M. Year: 2003 The military has begun to encourage collaborative relationships--through formal memorandums of understanding (MOUs)--between military installations and neighboring communities intended to prevent and respond to domestic violence involving service members. The authors examine the challenges of and recommendations for establishing such MOUs. Title: Formalizing Collaboration: Establishing Domestic Violence Memorandums of Understanding Between Military Installations and Civilian Communities Author: Hickman, Laura J., Davis, Lois M. Year: 2003 The military has begun to encourage collaborative relationships--through formal memorandums of understanding (MOUs)--between military installations and neighboring communities intended to prevent and respond to domestic violence involving service members. The authors examine the challenges of and recommendations for establishing such MOUs. Close

• 46. [Article] Approaches to Making Military-Civilian Domestic Violence Collaborations Work: Lessons Learned From Two Case Studies

  To prevent and respond to domestic violence by or against service members, the military hopes to form and strengthen collaborative relationships between installations and neighboring communities. The authors ...

  Citation × Citation Citation Abstract Copy Title: Approaches to Making Military-Civilian Domestic Violence Collaborations Work: Lessons Learned From Two Case Studies Author: Hickman, Laura J., Davis, Lois M., Steinberg, Paul C. Year: 2004 To prevent and respond to domestic violence by or against service members, the military hopes to form and strengthen collaborative relationships between installations and neighboring communities. The authors present findings from two case studies of military-civilian collaboration and offer suggestions for forming and strengthening these relationships. Title: Approaches to Making Military-Civilian Domestic Violence Collaborations Work: Lessons Learned From Two Case Studies Author: Hickman, Laura J., Davis, Lois M., Steinberg, Paul C. Year: 2004 To prevent and respond to domestic violence by or against service members, the military hopes to form and strengthen collaborative relationships between installations and neighboring communities. The authors present findings from two case studies of military-civilian collaboration and offer suggestions for forming and strengthening these relationships. Close

• 47. [Article] Beavers, firs, salmon, and falling water: Pacific Northwest regionalism and the environment

  Discusses the importance of salmon in defining environmental understanding in the Pacific Northwest. Dam construction, population influx, economic development, and politics have dramatically changed the ...

  Citation × Citation Citation Abstract Copy Title: Beavers, firs, salmon, and falling water: Pacific Northwest regionalism and the environment Author: Lang, William L. Year: 2003 Discusses the importance of salmon in defining environmental understanding in the Pacific Northwest. Dam construction, population influx, economic development, and politics have dramatically changed the geography of Oregon Country since 1850. The technological alterations and population growth redefined the sense of place. However, salmon has remained the most important icon of the Pacific Northwest, both for Native Americans and for nonnatives have who worked to save the salmon from extinction. Salmon have become a "living metaphor" for the region, and their fate reflects an understanding of historical context and the role of people in their relationship to the environment in this particular region. Title: Beavers, firs, salmon, and falling water: Pacific Northwest regionalism and the environment Author: Lang, William L. Year: 2003 Discusses the importance of salmon in defining environmental understanding in the Pacific Northwest. Dam construction, population influx, economic development, and politics have dramatically changed the geography of Oregon Country since 1850. The technological alterations and population growth redefined the sense of place. However, salmon has remained the most important icon of the Pacific Northwest, both for Native Americans and for nonnatives have who worked to save the salmon from extinction. Salmon have become a "living metaphor" for the region, and their fate reflects an understanding of historical context and the role of people in their relationship to the environment in this particular region. Close

• 48. [Article] Simplified Framework Evaluation of Large Water Resource Project Impacts

  The document most frequently used to support a water resource project's economic feasibility is the commercial benefit-cost analysis, which quantifies tangible and direct project consequences. The objective ...

  Citation × Citation Citation Abstract Copy Title: Simplified Framework Evaluation of Large Water Resource Project Impacts Author: Clowes, Brian Woodbridge Year: 1988 The document most frequently used to support a water resource project's economic feasibility is the commercial benefit-cost analysis, which quantifies tangible and direct project consequences. The objective of this type of analysis is simply to maximize net monetary benefits. This analysis assigns an arbitrary monetary value to ecological and social disruptions, if it does not ignore these effects entirely. An improvement on this method is the social benefit-cost analysis, which assesses sane intangible costs such as air and noise pollution. Unfortunately, even the social analysis usually neglects the sometimes profound effects that a large water resource project has upon quality of life, particularly with regards to massive relocations. The purpose of this dissertation is to resolve these problems by presenting a method by which a water resource study team may use five unique viewpoints - technical, organizational, personal, social, and environmental - to quantify and compare the true benefits and costs of project construction and operation. The study team begins by rigorously documenting the three general categories of project consequence (economic, social and environmental) and assigning each benefit or cost a relative value within category according to perceived positive or negative effects. The second step is to use these quantifications to produce three impact vs. dam height curves. The final and most difficult step in this study process is to assign a relative weight to the respective economic, social, and enviromental impact clusters, depending on national priorities and the biases and personal viewpoints of the decisiomaker (s). The final product of this procedure is a single curve which is used to further investigate and assess the overall feasibility of a water resource project and the 'optimum' range of dam heights. All of the possible impacts of a large water resource project, whether they be tangible or intangible, should be investigated in order to produce an authentic indicator of project efficiency. The only way to insure that all impacts are properly accounted for is to perform an exhaustive examination of a water resource project from the five perspectives mentioned above. The body of this dissertation is an example analysis based upon the proposed Three Gorge Dam and Reservoir on the Yangtze River in the People's Republic of China. This project will be the world's largest power plant at 13,000 megawatts. Because of its size, anticipated impacts, and the interest it has generated all over the world, the Three Gorge project is considered the ideal subject of a comprehensive multiple perspective analysis as described in this study. Title: Simplified Framework Evaluation of Large Water Resource Project Impacts Author: Clowes, Brian Woodbridge Year: 1988 The document most frequently used to support a water resource project's economic feasibility is the commercial benefit-cost analysis, which quantifies tangible and direct project consequences. The objective of this type of analysis is simply to maximize net monetary benefits. This analysis assigns an arbitrary monetary value to ecological and social disruptions, if it does not ignore these effects entirely. An improvement on this method is the social benefit-cost analysis, which assesses sane intangible costs such as air and noise pollution. Unfortunately, even the social analysis usually neglects the sometimes profound effects that a large water resource project has upon quality of life, particularly with regards to massive relocations. The purpose of this dissertation is to resolve these problems by presenting a method by which a water resource study team may use five unique viewpoints - technical, organizational, personal, social, and environmental - to quantify and compare the true benefits and costs of project construction and operation. The study team begins by rigorously documenting the three general categories of project consequence (economic, social and environmental) and assigning each benefit or cost a relative value within category according to perceived positive or negative effects. The second step is to use these quantifications to produce three impact vs. dam height curves. The final and most difficult step in this study process is to assign a relative weight to the respective economic, social, and enviromental impact clusters, depending on national priorities and the biases and personal viewpoints of the decisiomaker (s). The final product of this procedure is a single curve which is used to further investigate and assess the overall feasibility of a water resource project and the 'optimum' range of dam heights. All of the possible impacts of a large water resource project, whether they be tangible or intangible, should be investigated in order to produce an authentic indicator of project efficiency. The only way to insure that all impacts are properly accounted for is to perform an exhaustive examination of a water resource project from the five perspectives mentioned above. The body of this dissertation is an example analysis based upon the proposed Three Gorge Dam and Reservoir on the Yangtze River in the People's Republic of China. This project will be the world's largest power plant at 13,000 megawatts. Because of its size, anticipated impacts, and the interest it has generated all over the world, the Three Gorge project is considered the ideal subject of a comprehensive multiple perspective analysis as described in this study. Close

• 49. [Article] Metacommunity Structure of Zooplankton in River Networks: Roles of Environmental and Spatial Factors

  Zooplankton in river systems have seldom been studied in the context of metacommunity ecology. Spatial factors (e.g., river connectivity, directionality, and man-made dams) may play a key role in influencing ...

  Citation × Citation Citation Abstract Copy Title: Metacommunity Structure of Zooplankton in River Networks: Roles of Environmental and Spatial Factors Author: Zhao, Kun, Song, Kun, Pan, Yangdong, Wang, Lizhu Year: 2017 Zooplankton in river systems have seldom been studied in the context of metacommunity ecology. Spatial factors (e.g., river connectivity, directionality, and man-made dams) may play a key role in influencing the metacommunity structure of rotifers because of their small body size and weak mobility. In contrast, local environmental factors (e.g., physicochemical habitat) may be more important to crustaceans due to their larger body size and stronger mobility. We sampled zooplankton and environmental factors during wet and dry seasons from 47 sites along the Ying River in China to assess the roles of the spatial and environmental factors in structuring zooplankton metacommunities. We used Moran’s eigenvector map and asymmetric eigenvector map to model the influences of river connectivity, directionality, and man-made dams on zooplankton metacommunity structure. We then used partial redundancy analysis to identify individual and interactive effects of spatial and environmental factors on both the entire zooplankton assemblages and two zooplankton groups of different body sizes and mobility. A total of 101 taxa were identified and taxa richness was higher in the wet season (72) than in the dry season (58). Zooplankton assemblages were primarily dominated by rotifers. For the dry season, environmental factors such as total nitrogen, water temperature, and pH explained a significant portion of variation in zooplankton community; river connectivity was more important than river directionality to zooplankton metacommunity structure. For the wet season, spatial factors were more influential than environmental factors such as dissolved oxygen and water transparency; river directionality played an important role in influencing the spatial structures of both environmental condition and zooplankton metacommunity. We also found significant effects of man-made dams on zooplankton metacommunity structure. Spatial factors are more influential in structuring small body size and weak mobility rotifer communities, while environmental factors are more important in determining the variation of crustaceans due to their larger body size and stronger mobility. We concluded that river connectivity and directionality should be considered as key factors for better understanding the spatial processes of planktonic passive dispersers in river networks. Our study provides new insight on understanding riverine zooplankton metacommunity ecology and contributes to the knowledge of river ecosystem health monitoring and management. Title: Metacommunity Structure of Zooplankton in River Networks: Roles of Environmental and Spatial Factors Author: Zhao, Kun, Song, Kun, Pan, Yangdong, Wang, Lizhu Year: 2017 Zooplankton in river systems have seldom been studied in the context of metacommunity ecology. Spatial factors (e.g., river connectivity, directionality, and man-made dams) may play a key role in influencing the metacommunity structure of rotifers because of their small body size and weak mobility. In contrast, local environmental factors (e.g., physicochemical habitat) may be more important to crustaceans due to their larger body size and stronger mobility. We sampled zooplankton and environmental factors during wet and dry seasons from 47 sites along the Ying River in China to assess the roles of the spatial and environmental factors in structuring zooplankton metacommunities. We used Moran’s eigenvector map and asymmetric eigenvector map to model the influences of river connectivity, directionality, and man-made dams on zooplankton metacommunity structure. We then used partial redundancy analysis to identify individual and interactive effects of spatial and environmental factors on both the entire zooplankton assemblages and two zooplankton groups of different body sizes and mobility. A total of 101 taxa were identified and taxa richness was higher in the wet season (72) than in the dry season (58). Zooplankton assemblages were primarily dominated by rotifers. For the dry season, environmental factors such as total nitrogen, water temperature, and pH explained a significant portion of variation in zooplankton community; river connectivity was more important than river directionality to zooplankton metacommunity structure. For the wet season, spatial factors were more influential than environmental factors such as dissolved oxygen and water transparency; river directionality played an important role in influencing the spatial structures of both environmental condition and zooplankton metacommunity. We also found significant effects of man-made dams on zooplankton metacommunity structure. Spatial factors are more influential in structuring small body size and weak mobility rotifer communities, while environmental factors are more important in determining the variation of crustaceans due to their larger body size and stronger mobility. We concluded that river connectivity and directionality should be considered as key factors for better understanding the spatial processes of planktonic passive dispersers in river networks. Our study provides new insight on understanding riverine zooplankton metacommunity ecology and contributes to the knowledge of river ecosystem health monitoring and management. Close

• 50. [Article] Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2

  The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, ...

  Citation × Citation Citation Abstract Copy Title: Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2 Author: Van Glubt, Sarah Year: 2017 The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids. Title: Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2 Author: Van Glubt, Sarah Year: 2017 The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids. Close