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• 1451. [Article] Glacier Change in the North Cascades, Washington: 1900-2009

  Glaciers respond to local climate changes making them important indicators of regional climate change. The North Cascades region of Washington is the most glaciated region in the lower-48 states with approximately ...

  Citation × Citation Citation Abstract Copy Title: Glacier Change in the North Cascades, Washington: 1900-2009 Author: Dick, Kristina Amanda Year: 2013 Glaciers respond to local climate changes making them important indicators of regional climate change. The North Cascades region of Washington is the most glaciated region in the lower-48 states with approximately 25% of all glaciers and 40% of the total ice-covered area. While there are many on-going investigations of specific glaciers, little research has addressed the entire glacier cover of the region. A reference inventory of glaciers was derived from a comparison of two different inventories dating to about 1958. The different inventories agree within 93% of total number of glaciers and 94% of total ice-covered area. To quantify glacier change over the past century aerial photographs, topographic maps, and geologic maps were used. In ~1900 total area was about 533.89 ± 22.77 km2 and by 2009 the area was reduced by -56% ± 3% to 236.20 ± 12.60 km2. Most of that change occurred in the first half of the 20th century, between 1900 and 1958, -245.59 ± 25.97 km2 (-46% ± 5%) was lost, followed by a period of stability/growth in mid-century (-1% ± 3% from 1958-1990) then decline since the 1990s (-9% ± 3% from 1990-2009). The century-scale loss is associated with increasing regional temperatures warming in winter and summer; precipitation shows no trend. On a decadal time scale winter precipitation and winter and summer temperatures are important factors correlated with area loss. Topographically, smaller glaciers at lower elevations with steeper slopes and higher mean insolation exhibited greater loss than higher, gentler more shaded glaciers. Title: Glacier Change in the North Cascades, Washington: 1900-2009 Author: Dick, Kristina Amanda Year: 2013 Glaciers respond to local climate changes making them important indicators of regional climate change. The North Cascades region of Washington is the most glaciated region in the lower-48 states with approximately 25% of all glaciers and 40% of the total ice-covered area. While there are many on-going investigations of specific glaciers, little research has addressed the entire glacier cover of the region. A reference inventory of glaciers was derived from a comparison of two different inventories dating to about 1958. The different inventories agree within 93% of total number of glaciers and 94% of total ice-covered area. To quantify glacier change over the past century aerial photographs, topographic maps, and geologic maps were used. In ~1900 total area was about 533.89 ± 22.77 km2 and by 2009 the area was reduced by -56% ± 3% to 236.20 ± 12.60 km2. Most of that change occurred in the first half of the 20th century, between 1900 and 1958, -245.59 ± 25.97 km2 (-46% ± 5%) was lost, followed by a period of stability/growth in mid-century (-1% ± 3% from 1958-1990) then decline since the 1990s (-9% ± 3% from 1990-2009). The century-scale loss is associated with increasing regional temperatures warming in winter and summer; precipitation shows no trend. On a decadal time scale winter precipitation and winter and summer temperatures are important factors correlated with area loss. Topographically, smaller glaciers at lower elevations with steeper slopes and higher mean insolation exhibited greater loss than higher, gentler more shaded glaciers. Close

• 1452. [Article] Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones)

  I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, ...

  Citation × Citation Citation Abstract Copy Title: Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones) Author: Welch, Brandi Lynn Year: 2016 I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic pattern emerged within A. occidentalis, with at least one northern and two southern populations. A clade containing all A. minimus sequences was recovered. However, this clade falls within the larger clade of A. occidentalis, rendering A. occidentalis paraphyletic. Furthermore, the A. minimus sequences showed north-south geographic structuring within the clade. Population genetic analyses were performed based on geographic location within the Pacific Northwest. I found high genetic differentiation coupled with low gene flow between most populations, with the exception of the Portland and North Coast Range populations. These data suggest the presence of more than two species of Apochthonius in the Pacific Northwest. Title: Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones) Author: Welch, Brandi Lynn Year: 2016 I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic pattern emerged within A. occidentalis, with at least one northern and two southern populations. A clade containing all A. minimus sequences was recovered. However, this clade falls within the larger clade of A. occidentalis, rendering A. occidentalis paraphyletic. Furthermore, the A. minimus sequences showed north-south geographic structuring within the clade. Population genetic analyses were performed based on geographic location within the Pacific Northwest. I found high genetic differentiation coupled with low gene flow between most populations, with the exception of the Portland and North Coast Range populations. These data suggest the presence of more than two species of Apochthonius in the Pacific Northwest. Close

• 1453. [Article] Geology, Alteration and Mineralization of a Silicic Volcanic Center, Glass Buttes, Oregon

  Glass Buttes, a Pliocene silicic volcanic complex within the High Lava Plains province of Oregon, was erupted approximately 5.0 to 5.8 million years ago. Geologic mapping revealed that the eastern portion ...

  Citation × Citation Citation Abstract Copy Title: Geology, Alteration and Mineralization of a Silicic Volcanic Center, Glass Buttes, Oregon Author: Johnson, Michael James Year: 1984 Glass Buttes, a Pliocene silicic volcanic complex within the High Lava Plains province of Oregon, was erupted approximately 5.0 to 5.8 million years ago. Geologic mapping revealed that the eastern portion of the complex is underlain by rhyolitic glass domes, flows and rare pyroclastis flows. Basalt flows are interlayered with and onlap the silicic glass. Younger basalt flows, erupted from local vents, overlie silicic glass and onlapping basalts. The eastern end of Glass Buttes is hydrothermally altered at the surface; a weak geothermal anomaly coincides with the altered areas. Alteration, localized by northwest trending normal faults, occurs primarily as opalite replacement of rhyolite glass with associated cinnabar, alunite, clay-rich vein material, hematite, and hyalite. Alteration paragenesis at the surface was defined, and physicochemical conditions during hydrothermal activity were inferred from alteration minerals and assemblages and trace element content of alteration minerals. Alteration identified in the subsurface is interpreted to be related to an older hydrothermal system. Carbonate, pyrite, quartz, and minor smectite and chlorite occur in vugs and fractures, and partially replace subsurface basalt. Abundant fine-grained disseminated pyrite occurs in permeable units. Pyrite separates from disseminations and veins within basalt and permeable glassy units contain up to 13 ppm Au. The pyrite samples are also anomalous with respect to arsenic and antimony. Title: Geology, Alteration and Mineralization of a Silicic Volcanic Center, Glass Buttes, Oregon Author: Johnson, Michael James Year: 1984 Glass Buttes, a Pliocene silicic volcanic complex within the High Lava Plains province of Oregon, was erupted approximately 5.0 to 5.8 million years ago. Geologic mapping revealed that the eastern portion of the complex is underlain by rhyolitic glass domes, flows and rare pyroclastis flows. Basalt flows are interlayered with and onlap the silicic glass. Younger basalt flows, erupted from local vents, overlie silicic glass and onlapping basalts. The eastern end of Glass Buttes is hydrothermally altered at the surface; a weak geothermal anomaly coincides with the altered areas. Alteration, localized by northwest trending normal faults, occurs primarily as opalite replacement of rhyolite glass with associated cinnabar, alunite, clay-rich vein material, hematite, and hyalite. Alteration paragenesis at the surface was defined, and physicochemical conditions during hydrothermal activity were inferred from alteration minerals and assemblages and trace element content of alteration minerals. Alteration identified in the subsurface is interpreted to be related to an older hydrothermal system. Carbonate, pyrite, quartz, and minor smectite and chlorite occur in vugs and fractures, and partially replace subsurface basalt. Abundant fine-grained disseminated pyrite occurs in permeable units. Pyrite separates from disseminations and veins within basalt and permeable glassy units contain up to 13 ppm Au. The pyrite samples are also anomalous with respect to arsenic and antimony. Close

• 1454. [Article] Engaging Global Service: Organizational Motivations for and Perceived Benefits of Hosting International Volunteers

  An increasingly popular way for global citizens to contribute to communities around the world is through international volunteering. In tandem with this growing trend, academic research in the field has ...

  Citation × Citation Citation Abstract Copy Title: Engaging Global Service: Organizational Motivations for and Perceived Benefits of Hosting International Volunteers Author: Barnhart, Erin Leslie Year: 2012 An increasingly popular way for global citizens to contribute to communities around the world is through international volunteering. In tandem with this growing trend, academic research in the field has increased to explore the goals, motivations, and impacts of international service on volunteers, host communities, and volunteer-sending organizations. One of the larger gaps in our understanding of global civic engagement though is the specifics of how and why, as well as the overall impact of international service on, host organizations that seek and/or accept international volunteers. Using an exploratory research design to collect and analyze survey data and open-ended email inquiry responses from almost 250 organizational representatives in 50+ countries, this dissertation expands the breadth and depth of knowledge on the relationship between host organizations and international volunteers. Findings include a broad and varied range of potential motivations for hosting international volunteers, from direct benefits to the host organization like leveraging organizational capacity to benefits extended to the broader community and volunteers themselves such as providing opportunities for cross-cultural interaction. In addition, host organization characteristics and opinions were compared between two global regions - Africa and Asia - and statistically significant relationships identified between characteristics and opinions of host organizations and their reported satisfaction with international volunteers. This study contributes new data on and from organizations that host international volunteers. Research findings also support and expand the field's understanding of international volunteer engagement as it relates specifically to organizational capacity and social capital theory. Title: Engaging Global Service: Organizational Motivations for and Perceived Benefits of Hosting International Volunteers Author: Barnhart, Erin Leslie Year: 2012 An increasingly popular way for global citizens to contribute to communities around the world is through international volunteering. In tandem with this growing trend, academic research in the field has increased to explore the goals, motivations, and impacts of international service on volunteers, host communities, and volunteer-sending organizations. One of the larger gaps in our understanding of global civic engagement though is the specifics of how and why, as well as the overall impact of international service on, host organizations that seek and/or accept international volunteers. Using an exploratory research design to collect and analyze survey data and open-ended email inquiry responses from almost 250 organizational representatives in 50+ countries, this dissertation expands the breadth and depth of knowledge on the relationship between host organizations and international volunteers. Findings include a broad and varied range of potential motivations for hosting international volunteers, from direct benefits to the host organization like leveraging organizational capacity to benefits extended to the broader community and volunteers themselves such as providing opportunities for cross-cultural interaction. In addition, host organization characteristics and opinions were compared between two global regions - Africa and Asia - and statistically significant relationships identified between characteristics and opinions of host organizations and their reported satisfaction with international volunteers. This study contributes new data on and from organizations that host international volunteers. Research findings also support and expand the field's understanding of international volunteer engagement as it relates specifically to organizational capacity and social capital theory. Close

• 1455. [Article] Chemical and Petrographic Survey of Large, Igneous-Textured Inclusions in Ordinary Chondrites

  Our inventory of material from the early solar system includes large, igneous-textured inclusions in O chondrites, whose origin and relationship to their host meteorite is unclear. These inclusions occur ...

  Citation × Citation Citation Abstract Copy Title: Chemical and Petrographic Survey of Large, Igneous-Textured Inclusions in Ordinary Chondrites Author: Armstrong, Katherine Year: 2014 Our inventory of material from the early solar system includes large, igneous-textured inclusions in O chondrites, whose origin and relationship to their host meteorite is unclear. These inclusions occur in approximately 4% of O chondrites, and are mineralogically, petrographically, and chemically diverse. Petrographic and chemical data from 29 inclusions from 23 host meteorites were collected with optical light and scanning electron microscopy, allowing for the determination of major phase modal abundance and major element bulk chemistry. No correlation between any inclusion property and host meteorite type were found, but some trends were observed. Nine of the inclusions show strong evidence, such as radial variations in texture and chemistry, for having crystallized as a free-floating droplet in a space environment, and may share the same formation process as chondrules. One inclusion is almost certainly shock-melted material that intruded into the host material. Thirteen inclusions have bulk chemistry patterns that suggest the material was vapor fractionated; the remaining sixteen are essentially chondritic, i.e., unfractionated. Broadly, the data support the conclusions of Ruzicka et al. (1998, 2000), which divided large inclusions into Na-poor (vapor fractionated) and Na-rich (unfractionated) groups, suggesting at least two different origins. There is no evidence that any of the inclusions studied formed by igneous differentiation. Title: Chemical and Petrographic Survey of Large, Igneous-Textured Inclusions in Ordinary Chondrites Author: Armstrong, Katherine Year: 2014 Our inventory of material from the early solar system includes large, igneous-textured inclusions in O chondrites, whose origin and relationship to their host meteorite is unclear. These inclusions occur in approximately 4% of O chondrites, and are mineralogically, petrographically, and chemically diverse. Petrographic and chemical data from 29 inclusions from 23 host meteorites were collected with optical light and scanning electron microscopy, allowing for the determination of major phase modal abundance and major element bulk chemistry. No correlation between any inclusion property and host meteorite type were found, but some trends were observed. Nine of the inclusions show strong evidence, such as radial variations in texture and chemistry, for having crystallized as a free-floating droplet in a space environment, and may share the same formation process as chondrules. One inclusion is almost certainly shock-melted material that intruded into the host material. Thirteen inclusions have bulk chemistry patterns that suggest the material was vapor fractionated; the remaining sixteen are essentially chondritic, i.e., unfractionated. Broadly, the data support the conclusions of Ruzicka et al. (1998, 2000), which divided large inclusions into Na-poor (vapor fractionated) and Na-rich (unfractionated) groups, suggesting at least two different origins. There is no evidence that any of the inclusions studied formed by igneous differentiation. Close

• 1456. [Article] Growing STEM Education on the Playground: A Case Study of the Factors That Influence Teachers’ Use of School Gardens

  School gardens can have a profound, positive influence on a student's academic achievement, social skills, and attitudinal orientation. Despite these clear benefits, the use of school gardens as an instructional ...

  Citation × Citation Citation Abstract Copy Title: Growing STEM Education on the Playground: A Case Study of the Factors That Influence Teachers’ Use of School Gardens Author: Poole, Megan Year: 2016 School gardens can have a profound, positive influence on a student's academic achievement, social skills, and attitudinal orientation. Despite these clear benefits, the use of school gardens as an instructional medium is not as prevalent as would be expected. There are several types of obstacles that can prevent teachers from using school gardens, including facets of time, support, and knowledge-based challenges. This multiple case study employs a mixed methods design to uncover factors that influence primary school teachers' decisions to utilize a school garden in their STEM curriculum. The goals of this study were to determine the types of benefits and barriers primary school teachers encountered in the study school district. All of the teacher participants worked within the same school district, had access to established school gardens on their campus, and were supported in their instruction and use of materials by the district's Science and Technology Center (STC). Quantitative data was collected from garden resource and teacher self-efficacy surveys; qualitative data about teacher rationales was extracted from in-depth teacher interviews. Overall analyses determined that aspects of instruction and logistics were the most important factors for a teacher to have in her decision to utilize her school garden. These data are presented and discussed in the context of identifying trends in teachers' use of school gardens as instructional tools so that actions might be taken to remove barriers and increase curriculum opportunities. Title: Growing STEM Education on the Playground: A Case Study of the Factors That Influence Teachers’ Use of School Gardens Author: Poole, Megan Year: 2016 School gardens can have a profound, positive influence on a student's academic achievement, social skills, and attitudinal orientation. Despite these clear benefits, the use of school gardens as an instructional medium is not as prevalent as would be expected. There are several types of obstacles that can prevent teachers from using school gardens, including facets of time, support, and knowledge-based challenges. This multiple case study employs a mixed methods design to uncover factors that influence primary school teachers' decisions to utilize a school garden in their STEM curriculum. The goals of this study were to determine the types of benefits and barriers primary school teachers encountered in the study school district. All of the teacher participants worked within the same school district, had access to established school gardens on their campus, and were supported in their instruction and use of materials by the district's Science and Technology Center (STC). Quantitative data was collected from garden resource and teacher self-efficacy surveys; qualitative data about teacher rationales was extracted from in-depth teacher interviews. Overall analyses determined that aspects of instruction and logistics were the most important factors for a teacher to have in her decision to utilize her school garden. These data are presented and discussed in the context of identifying trends in teachers' use of school gardens as instructional tools so that actions might be taken to remove barriers and increase curriculum opportunities. Close

• 1457. [Article] Wiki-based Collaborative Creative Writing in the ESL Classroom

  Despite the growing number of L2 studies examining digitally-mediated collaborative writing, the vast majority of these studies have focused on academic writing tasks. This study examined the dynamics ...

  Citation × Citation Citation Abstract Copy Title: Wiki-based Collaborative Creative Writing in the ESL Classroom Author: Elabdali, Rima Year: 2016 Despite the growing number of L2 studies examining digitally-mediated collaborative writing, the vast majority of these studies have focused on academic writing tasks. This study examined the dynamics and perceptions of groups of ESL students who used wikis to write collaborative short stories. The study also compared the short stories written in groups with posttest short stories written individually in terms of creativity, accuracy, and complexity. The study involved nine students taking a Creative Writing course in an intensive English program at a large university in the U.S. It followed a multiple case study design; the students were divided into three pairs and one triad (four case studies). For three weeks, the groups engaged in a series of wiki-based and creative writing activities and produced four collaborative short stories. During the following three-week period, the students wrote nine individual short stories using a similar writing prompt to the one used in the collaborative task. For each student, the collaborative and individual writing samples were compared on the three dimensions of creativity, accuracy, and complexity to examine whether collaboration influenced the quality of the product. Further, the dynamics of collaboration were explored through analyzing the wiki discussions and revision histories for each group. Finally, students’ perceptions of the task were surveyed through individual interviews and self-assessment questionnaires. While there was not a clear effect of collaboration on the creativity and accuracy of the short stories, the complexity was slightly higher for the majority of the informants. The analysis of the short stories also indicated that ESL students faced difficulty writing in a genre that does not have a strict pre-established outline. Analysis of the wiki discussions and revision history showed trends of group dynamics in the four case studies. Further analysis of perception data revealed that although the majority of the informants had a negative perception of the collaborative task, they expressed a positive attitude toward the individual creative writing task. Title: Wiki-based Collaborative Creative Writing in the ESL Classroom Author: Elabdali, Rima Year: 2016 Despite the growing number of L2 studies examining digitally-mediated collaborative writing, the vast majority of these studies have focused on academic writing tasks. This study examined the dynamics and perceptions of groups of ESL students who used wikis to write collaborative short stories. The study also compared the short stories written in groups with posttest short stories written individually in terms of creativity, accuracy, and complexity. The study involved nine students taking a Creative Writing course in an intensive English program at a large university in the U.S. It followed a multiple case study design; the students were divided into three pairs and one triad (four case studies). For three weeks, the groups engaged in a series of wiki-based and creative writing activities and produced four collaborative short stories. During the following three-week period, the students wrote nine individual short stories using a similar writing prompt to the one used in the collaborative task. For each student, the collaborative and individual writing samples were compared on the three dimensions of creativity, accuracy, and complexity to examine whether collaboration influenced the quality of the product. Further, the dynamics of collaboration were explored through analyzing the wiki discussions and revision histories for each group. Finally, students’ perceptions of the task were surveyed through individual interviews and self-assessment questionnaires. While there was not a clear effect of collaboration on the creativity and accuracy of the short stories, the complexity was slightly higher for the majority of the informants. The analysis of the short stories also indicated that ESL students faced difficulty writing in a genre that does not have a strict pre-established outline. Analysis of the wiki discussions and revision history showed trends of group dynamics in the four case studies. Further analysis of perception data revealed that although the majority of the informants had a negative perception of the collaborative task, they expressed a positive attitude toward the individual creative writing task. Close

• 1458. [Article] Regional Travel Options 2007-08 Program Evaluation

  To help implement the Growth Concept, Metro’s Regional Travel Options (RTO) Program works to increase awareness of non-SOV alternatives and increase the provision of those alternatives. The program complements ...

  Citation × Citation Citation Abstract Copy Title: Regional Travel Options 2007-08 Program Evaluation Author: Dill, Jennifer, Brown, Stephan Year: 2010 To help implement the Growth Concept, Metro’s Regional Travel Options (RTO) Program works to increase awareness of non-SOV alternatives and increase the provision of those alternatives. The program complements other strategies, including land use policies and infrastructure investment. The most comprehensive data available for this evaluation come from commute surveys of employees at work sites that participate in outreach programs offered by TriMet. All of the RTO evaluations have used these data as a benchmark for overall progress, though the data only captures commute travel. The 2008 data reflect the commute patterns of about 120,000 employees commuting to 549 worksites. The long-term trend is positive, with the share of work trips made by modes other than single-occupant vehicles (SOVs) generally increasing since 1996 Figure 3. However, the data for 2007 and 2008 show a decline since 2006 in the share of work trips made on transit. Increases in bicycling and walking, compressed work weeks, and telecommuting helped offset that decline. The share of trips made in carpools and vanpools has remained about the same for the past four years, and is still lower than 1996. Title: Regional Travel Options 2007-08 Program Evaluation Author: Dill, Jennifer, Brown, Stephan Year: 2010 To help implement the Growth Concept, Metro’s Regional Travel Options (RTO) Program works to increase awareness of non-SOV alternatives and increase the provision of those alternatives. The program complements other strategies, including land use policies and infrastructure investment. The most comprehensive data available for this evaluation come from commute surveys of employees at work sites that participate in outreach programs offered by TriMet. All of the RTO evaluations have used these data as a benchmark for overall progress, though the data only captures commute travel. The 2008 data reflect the commute patterns of about 120,000 employees commuting to 549 worksites. The long-term trend is positive, with the share of work trips made by modes other than single-occupant vehicles (SOVs) generally increasing since 1996 Figure 3. However, the data for 2007 and 2008 show a decline since 2006 in the share of work trips made on transit. Increases in bicycling and walking, compressed work weeks, and telecommuting helped offset that decline. The share of trips made in carpools and vanpools has remained about the same for the past four years, and is still lower than 1996. Close

• 1459. [Article] Leveraging Contextual Relationships Between Objects for Localization

  Object localization is currently an active area of research in computer vision. The object localization task is to identify all locations of an object class within an image by drawing a bounding box around ...

  Citation × Citation Citation Abstract Copy Title: Leveraging Contextual Relationships Between Objects for Localization Author: Olson, Clinton Leif Year: 2015 Object localization is currently an active area of research in computer vision. The object localization task is to identify all locations of an object class within an image by drawing a bounding box around objects that are instances of that class. Object locations are typically found by computing a classification score over a small window at multiple locations in the image, based on some chosen criteria, and choosing the highest scoring windows as the object bounding-boxes. Localization methods vary widely, but there is a growing trend towards methods that are able to make localization more accurate and efficient through the use of context. In this thesis, I investigate whether contextual relationships between related objects can be leveraged to improve localization efficiency through a reduction in the number of windows considered for each localization task. I implement a context-driven localization model and evaluate it against two models that do not use context between objects for comparison. My model constrains the search spaces for the target object location and window size. I show that context-driven methods substantially reduce the mean number of windows necessary for localizing a target object versus the two models not using context. The results presented here suggest that contextual relationships between objects in an image can be leveraged to significantly improve localization efficiency by reducing the number of windows required to find the target object. Title: Leveraging Contextual Relationships Between Objects for Localization Author: Olson, Clinton Leif Year: 2015 Object localization is currently an active area of research in computer vision. The object localization task is to identify all locations of an object class within an image by drawing a bounding box around objects that are instances of that class. Object locations are typically found by computing a classification score over a small window at multiple locations in the image, based on some chosen criteria, and choosing the highest scoring windows as the object bounding-boxes. Localization methods vary widely, but there is a growing trend towards methods that are able to make localization more accurate and efficient through the use of context. In this thesis, I investigate whether contextual relationships between related objects can be leveraged to improve localization efficiency through a reduction in the number of windows considered for each localization task. I implement a context-driven localization model and evaluate it against two models that do not use context between objects for comparison. My model constrains the search spaces for the target object location and window size. I show that context-driven methods substantially reduce the mean number of windows necessary for localizing a target object versus the two models not using context. The results presented here suggest that contextual relationships between objects in an image can be leveraged to significantly improve localization efficiency by reducing the number of windows required to find the target object. Close

• 1460. [Article] State Need-Based Aid and Four-Year College Student Retention: A Statewide Study

  Every college age student should have the opportunity to attend college and earn a degree, but the fiscal realities for lower income students prevent the majority from attending and the vast majority from ...

  Citation × Citation Citation Abstract Copy Title: State Need-Based Aid and Four-Year College Student Retention: A Statewide Study Author: McFall, Kara Lynn Year: 2013 Every college age student should have the opportunity to attend college and earn a degree, but the fiscal realities for lower income students prevent the majority from attending and the vast majority from completing college, thus perpetuating an intergenerational trend of limited postsecondary education and a likelihood of marginal income and status. Past research studies have shown that, among lower income students, those who receive higher levels of grant funding to offset college expenses are more likely to persist toward completing their educations than those who do not receive the same level of grant funding and thus are forced to rely upon other means, such as student loans or employment, to pay for college. The majority of this research was conducted prior to the recession that began in December 2007 (National Bureau of Economic Research, 2008), which has been more severe and longer lasting than any economic contraction since the Great Depression (Dwyer & Lothian, 2012); more current research is needed to determine whether the educational retention behaviors of lower income students in the current challenging economic climate are positively impacted by grant funding. In this study I used quantitative methods to analyze a specific state policy change to determine whether a significant change in the grant funding provided to lower income students resulted in increased retention rates for these students. This study examines school years from 2006-2010, thus encompassing the recent financial crisis and affording an opportunity to explore the persistence behaviors of lower income students during the greatest financial crisis of modern times. The ultimate purpose of the study is to provide conclusions from the research to postsecondary policy makers in the hopes of informing policy and supporting continuing funding of need-based financial aid for lower income students. Title: State Need-Based Aid and Four-Year College Student Retention: A Statewide Study Author: McFall, Kara Lynn Year: 2013 Every college age student should have the opportunity to attend college and earn a degree, but the fiscal realities for lower income students prevent the majority from attending and the vast majority from completing college, thus perpetuating an intergenerational trend of limited postsecondary education and a likelihood of marginal income and status. Past research studies have shown that, among lower income students, those who receive higher levels of grant funding to offset college expenses are more likely to persist toward completing their educations than those who do not receive the same level of grant funding and thus are forced to rely upon other means, such as student loans or employment, to pay for college. The majority of this research was conducted prior to the recession that began in December 2007 (National Bureau of Economic Research, 2008), which has been more severe and longer lasting than any economic contraction since the Great Depression (Dwyer & Lothian, 2012); more current research is needed to determine whether the educational retention behaviors of lower income students in the current challenging economic climate are positively impacted by grant funding. In this study I used quantitative methods to analyze a specific state policy change to determine whether a significant change in the grant funding provided to lower income students resulted in increased retention rates for these students. This study examines school years from 2006-2010, thus encompassing the recent financial crisis and affording an opportunity to explore the persistence behaviors of lower income students during the greatest financial crisis of modern times. The ultimate purpose of the study is to provide conclusions from the research to postsecondary policy makers in the hopes of informing policy and supporting continuing funding of need-based financial aid for lower income students. Close