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Online Crime Reporting: A new threat to police legitimacy?
Get PDFPolice are more likely to be perceived as legitimate when officers are procedurally just during interactions with the public (i.e. impartial, transparent, fair and respectful). Efforts to reinforce these skills have largely focused on contacts initiated by officers. Less attention has been paid to interactions with crime victims. Moreover, in recent years many police departments have sought to increase efficiency by directing victims to report online, rather than communicating directly with an officer. Very little is known about how victims experience online reporting systems. This study surveyed 1,198 property crime victims who used a large US police department’s online reporting portal. The primary objective was to evaluate the online reporting system using a procedural justice lens. One out of eight respondents said the agency’s online system was difficult to use, and just 16.7% were satisfied with the agency’s handling of their online report. Bivariate and multivariate analyses are used to identify factors associated with satisfaction, and qualitative data are used to document the specific problems victims encountered while using the online portal. Recommendations for improving online reporting are provided, including a discussion of enhancing procedural justice in technology-mediated police communications
Modern Trail of Tears: The Commodification of First Foods and Medicines in Relation to Food Apartheid and Genocide of Indigenous Peoples
Get PDFI am asking you to share in a cultural conversation with me. I will use different fonts in order to express my autobiographical and ethnographic Indigenous story separate from traditional academic writing This will not be a traditional thesis by any means of academic writing; this will also be a living document in a format of a cited reflection in order to continue the conversation not only through my Indigenous Research but also through community, and ideally will create everlasting solutions. However, this will be an introduction into my Indigenous writing and Indigenous voice.
I will be discussing the next steps of my ethnographic, autobiographical thesis which is a method that I have been focusing on over the last several years that was introduced to me by Indigenous scholars Rachel Black Elk (Lakota, Lumbee) and Renea Perry (Tlingit/Inupiat/N. European) of Portland State University. I recognized the importance of this style as I found my voice in academic writing, after the month that I spent traveling in Kenya in July 2023. I am working in the ideology of a scholarly cited reflection and have been reading Indigenous scholarship in this format as well to draw further inspiration and direction. I will also introduce additional Indigenous Scholarship that I will be studying as I continue to write my thesis in order to deconstruct, decolonize and Re-Indigenize myself as well as my writing and this process. This thesis is an open invitation to the public beyond academia and will be presented as such to the communities as a living document
Projected Loss of Rock Glacier Habitat in the Contiguous Western United States with Warming
Get PDFRock glaciers support alpine biodiversity and may respond more slowly to warming than snow or glaciers. While responses of snow and glaciers to climate change are relatively well understood, a robust assessment of rock glacier environmental niche, future distributions of rock glaciers and potential for development of rock glaciers from current glaciers is lacking. Using process-relevant, high-resolution environmental descriptors, we develop a species distribution model of the topographic, geologic and hydroclimatic niche of rock glaciers that provides novel estimates of potential rock glacier distributions for different climates. We identify mean annual air temperature and headwall area as the dominant controls on rock glacier spatial distributions, with rock glaciers more likely to be found in areas with mean annual temperatures close to −5°C, little rain, northern aspects and broad headwalls. While rock glacier climate equilibration may take hundreds of years, we find that equilibration to present climate will result in a 50% reduction in rock glacier habitat and equilibration to late 21st-century climate under a high-end warming scenario will result in a 99% reduction in rock glacier habitat across the western USA. Under future conditions, we find limited potential for glacier to rock glacier transformation (3% of glacierized area), concentrated in cold, high elevation, moderate precipitation areas
Exploring the Relationship Between COVID-19 Transmission and Population Mobility over Time
Get PDFThis study explores the dynamic relationship between COVID-19 transmission and transportation mobility, with an emphasis on understanding the time-varying bidirectional interplay across the different phases of the pandemic. To gain insight into this relationship, we analyzed county-level data on transmission and mobility patterns from the United States over a 74-week period using a comprehensive list of factors including: temporal factors, socio-demographics, health indicators, health care infrastructure attributes, and spatial factors. For our analysis, we proposed a simultaneous econometric model system that explicitly accounts for the bidirectional relationship between COVID-19 transmission and mobility patterns while also accounting for the influence of common unobserved factors on the two variables. The model results strongly support our hypothesis that COVID-19 transmission and mobility patterns are interconnected. Further, our findings show distinct phases of the bidirectional relationship influenced by behavior changes, vaccine availability, and the emergence of new variants. Additionally, we conducted a validation exercise on a hold-out sample to assess the robustness of our model. The results confirm the superiority of the simultaneous model system with enhanced interpretability and prediction capability. By analyzing data from several weeks for the COVID-19 pandemic, our study provides valuable insights into the evolving dynamics and potential strategies for future pandemics
Re-Evaluating Hypertragulid Diversity in the John Day Basin, Oregon, USA
Get PDFDespite their relative abundance, members of the family Hypertragulidae (Artiodactyla, Mammalia) have proved a conundrum regarding species diversity in the Turtle Cove Member (Oligocene) of the John Day Formation, located in central and eastern Oregon. Three species and two separate genera are described in the area, but previous research lacks statistical support for this level of variation. We use coefficients of variation (V) on measurements of dentition and astragali of hypertragulid specimens designated Hypertragulus hesperius, Hypertragulus minutus, and Nanotragulus planiceps as a metric for determining whether there were multiple species present in the population. Asymptotic and modified signed-likelihood ratio V equality tests show that V values of anterior-posterior molar length and transverse molar width vary significantly when comparing single species of modern ecological analogs (Muntiacus muntjak, Muntiacus reevesi, and Tragulus javanicus) to groupings of a combined population. However, the V equality tests on dental and postcranial measurements yield almost no significant results when comparing variation in the extinct John Day hypertragulids to an extant population comprised of a single species. Similar comparisons between astragali measurements of hypertragulids and T. javanicus express no significant difference in the level of variation from the combined population to a modern single species. The low level of variation in the hypertragulids and the lack of differentiation between dental characters of individuals does not statistically support the hypothesis that there were multiple species present in the population, suggesting either that cryptic species may be present but impossible to identify without soft tissue remains, or there may have been taxonomic over-splitting of a single hypertragulid species in the John Day region
Thermal Regimes of Beaver Impacted Stream Reaches in the Tualatin River Basin
No full textClimate change and urbanization are expected to cause major changes to hydrologic regimes over the Pacific Northwest Region. The Tualatin River Basin, an area of the Pacific Northwest just west of Portland, OR has been subjected to considerable water-quality issues, including stream temperature. As ecosystem engineers, beavers have the potential to mitigate stream degradation and, consequently, there is increasing interest in beaver-related restoration. However, different conclusions have been found on beaver dam impacts to stream thermal regimes. These differences have been attributed to geographical differences in study location and variability in methods and investigated spatiotemporal scales. We investigated summer thermal regimes of three beaver impacted stream reaches of tributaries to the Tualatin River using fiber-optic distributed temperature sensing techniques. Our study approach allowed us to compare thermal regimes across multiple spatial scales. We found considerable variability in thermal regimes among beaver impacted reaches that were influenced by air temperatures, stream depths, surrounding vegetation, and location along study reaches. Thermal sensitivity of the three impacted stream reaches was significantly different (p \u3c0.001). Daily maximum stream temperatures and daily stream temperature range were significantly different (p \u3c0.05) depending on location within stream reach and proximity to beaver dams. Daily maximum stream temperatures were higher in areas of the study reach that had shallow stream depths, and lower in areas that had deeper stream depths. Comparatively, daily maximum temperatures were greater in both areas that had high and low percent canopy cover, indicating stream depth may be more important for influencing daily maximum stream temperatures. Additionally, temperature differences surrounding beaver dams were, on average, cooler downstream when stream depths were greater downstream compared to upstream of beaver dams and warmer, on average, when stream depths were shallower downstream compared to upstream of beaver dams. Our results indicate thermal regimes in beaver impacted reaches are influenced by local factors and vary across spatial scales. Fully understanding the role beaver dams play in influencing stream temperatures requires multi-scale study approaches
A PWM Control Method for Reducing Electromagnetic Noise at the Generation Source in Power Electronic Converters
Get PDFAdvancements in power semiconductor devices are enabling the design of better electrical power conversion systems. Wide Bandgap (WBG) switching devices using materials like Silicon Carbide and Gallium Nitride can operate at higher temperatures, voltages, and frequencies with faster turn-on/off periods, improving converter performance over silicon devices. However, WBG technologies are still new, and the rapid switching transitions of these devices lead to issues such as voltage overshoots, ringing, and electromagnetic interference, which need to be addressed for widespread adoption. This work introduces a new control method for reshaping the switching voltages, which overcomes the disadvantages of fast transition time without increasing system losses. In fact, the proposed method reduces overall switching losses.
Experimental results on a small-scale prototype have shown that silicon-based devices improved the efficiency of a 380W DC-DC converter from 78% to 87% and reduced noise by 20dB+. A maximum of 9% efficiency improvement was observed in a 220W 100Vin DC to 100Vrms three-phase AC converter. Using Silicon Carbide (SiC) devices for 750W DC-DC and DC-AC converters resulted in about 15dB to 20dB+ reduction in electrical noise and about 1% efficiency improvement in the proposed case compared to the conventional switching method. The system Electromagnetic Interference (EMI) performance under proposed and classical switching methods is tested and compared, and results show about 5dB to 10dB reduction in conducted EMI for frequencies above 1MHz to 30MHz range. The proposed control technique allows breaking the relationship between converter efficiency and electromagnetic noise in state-of-the-art solutions, thereby speeding up the adoption of new WBG-based power-switching devices by addressing challenges related to electromagnetic noise, leading to higher power density and efficiency
Fast-Tracking Transit: Unveiling Portland\u27s First Bus Rapid Transit Line and Signal Optimization Strategies
Get PDFThis presentation on the Division Transit Project will provide an overview of the project elements including roadway design, bus station design, traffic signal timing and operations and the Next Gen Transit Signal Priority (TSP) system. We will discuss some lessons learned and provide before and after results from the project.https://pdxscholar.library.pdx.edu/trec_seminar/1258/thumbnail.jp
Addressing Transportation Emissions through State Climate and Energy Policy
Get PDFOregon has adopted policies to reduce greenhouse gas emissions from the energy and transportation sectors. This presentation will provide some background on these policy frameworks and explore how these policies impact transportation fuels and the transportation sector more broadly.https://pdxscholar.library.pdx.edu/trec_seminar/1257/thumbnail.jp
LSP Needs Analysis in the Context of International Minor League Baseball
Get PDFExamining the language and cultural needs of international minor league baseball players through the lens of English for Specific Purposes (ESP) this study utilizes applied linguistics and sports sociology and aims to inform player development strategies to enhance on- and off-field communication. Survey data was gathered on language use preferences, focusing on players\u27 attitudes and behaviors in professional settings. Ethical considerations included surveys in English and Spanish and voluntary participation, with data collected at the Oakland Athletics Complex in Mesa, Arizona, from 18 out of 20 players.
Findings reveal that players recognize the importance of English proficiency for effective gameplay and communication in the U.S., prioritizing baseball-specific vocabulary for communication with coaches and teammates. The study also highlights players\u27 desire for autonomy and authenticity in communication and the need for integrating baseball-specific content into language education programs.
Implications for player development and language education emphasize tailored approaches such as live classes, conversation focused curriculum, and maximizing speaking time to address the unique linguistic and cultural needs of international minor league players