Free and open source GIS in South America: political inroads and local advocacy

Geographical information systems (GIS) practitioners worldwide enjoy a growing array of free and open source software (FOSS) options. This software has expanded the accessibility of GIS in economically developing countries while fostering local technical expertise. This article reviews FOSS GIS uptake and advocacy in South America, especially how it relates to a climate of political friendliness toward FOSS in the region. The use or absence of FOSS GIS is assessed in public-facing web maps in South America, first at the national government level, and then at the provincial level using Argentina as a country of study. Local technical support groups and software development initiatives surrounding FOSS GIS in South America are then summarized. Finally, three case studies are presented of notable efforts to build FOSS GIS technical communities at the local level: the FOSSGIS Brasil online magazine, the Geoinquietos Argentina professional network, and the FOSS.4GIS.GOV conference in Brazil. A study of the leaders, dynamics, and practices of these groups can inform others in similar circumstances around the world who are trying to promote FOSS GIS adoption, development, skills, and services

Geographies of Empty Spaces on Print and Digital Reference Maps: A Study of Washington State

J. B. Harley’s insistence that “there is no such thing as an empty space on a map” invites critical inquiry into which places are being left blank in popular reference maps, and why. I discuss the myriad reasons that items may not appear on a map, and invite a rethinking of the way selection is conceptualized in cartographic education. In this study, several GIS-supported methods are used to identify and compare consistently empty areas in print and digital maps of Washington State made by Google, Microsoft, OpenStreetMap, Rand McNally, National Geographic, and the state Department of Transportation. I then examine the physical and human landscapes of these places using imagery overlays, queries of land ownership data, and observations from site visits. In the state of Washington, empty spaces on the map are highly connected with regional and global economies, and are essential for supporting the needs of urban life such as food, electricity, construction, and waste disposal. City dwellers may not ever see or recognize the intensive land uses occurring in these geographies, whose landowners include an intriguing mix of large industries, multiple levels of government, religious colonies, and individuals searching for space and solitude

Hamming Codes

We will be looking into the application of Matrix Algebra in forming Hamming Codes. Hamming Codes are essential not just in the detection of errors, but also in the linear concurrent correction of these errors. The matrices we will use, will have entries that are binary units. Binary units are mathematically convenient, and their simplicity permits the representation of many open and closed circuits used in communication systems. The entries in the matrices will represent a message that is meant for transmission or reception, akin to the contemporary application of Hamming Codes in wireless communication. We will use Hamming (7,4) Codes which are linear subspaces of the 7-dimensional vector space over F2, the base field

Using Free and Open Source Software to Teach University GIS Courses Online: Lessons Learned During a Pandemic

During the remote learning necessitated by the COVID-19 pandemic, university GIS students did not always have home access to the kinds of software and hardware that they would ordinarily get in their on-campus lab facilities. In this situation, the free and cross-platform nature of FOSS opened the door for some students to continue their GIS education uninterrupted. In this article, I describe how one university allowed students to choose FOSS such as QGIS, PostGIS, and GeoDa as alternatives to proprietary software in upper-division GIS coursework. These were used to teach techniques such as point pattern analysis, visibility analysis, hydrological modeling, proximity surfaces, LISA analysis, process modeling, open data access, and data summation. I share specific software tools, commands, and plugins used to apply these techniques in lab assignments. I discuss how these approaches can form a lasting part of the GIS curriculum beyond the pandemic, and how students can position these FOSS skills as they prepare for the GIS job market

What can we see from the road? Applications of a cumulative viewshed analysis on a US state highway network

In many parts of the world, motorized travel is one of the most common ways that people interact with their regional landscape. This study investigates how travelers\u27 understandings of place might be influenced by what landforms they can see from a vehicle. It uses a cumulative viewshed analysis on the Washington State (United States) highway network to determine which physical landscape features are most frequently visible or obscured from the road. Adapting ideas from Kevin Lynch\u27s The Image of the City, I propose spatial data processing methods to derive landmarks, edges, and districts that could most contribute to the mental maps of travelers and should be prioritized for labeling on print, electronic, and augmented reality maps. Other applications of the cumulative viewshed include deriving scenic byways, siting proposed construction for high or low visibility, and guiding conversations about critical toponymy and perceptions of place

Diagnostic Medical Errors: Patient\u27s Perspectives on a Pervasive Problem

Introduction. The Institute of Medicine defines diagnostic error as the failure to establish an accurate or timely explanation for the patient\u27s health problem(s), or effectively communicate the explanation to the patient. To our knowledge, no studies exist characterizing diagnostic error from patient perspectives using this definition. Objective. We sought to characterize diagnostic errors experienced by patients and describe patient perspectives on causes, impacts, and prevention strategies. Methods. We screened 77 adult inpatients at University of Vermont Medical Center and conducted 27 structured interviews with patients who experienced diagnostic error in the past five years. We performed qualitative analysis using Grounded Theory. Results. In the past five years, 39% of interviewed patients experienced diagnostic error. The errors mapped to the following categories: accuracy (30%), communication (34%) and timeliness (36%). Poor communication (13 responses) and inadequate time with doctors (7) were the most identified causes of errors. Impacts of errors included emotional distress (17 responses), adverse health outcomes (7) and impaired activities of daily living (6). Patients suggested improved communication (11 responses), clinical management (7) and access to doctors (5) as prevention strategies. For communication, patients rated talk to your doctor highest (mean 8.4, on 1-10 Likert scale) and text message lowest (4.8). Conclusions/Recommendations. Diagnostic errors are common and have dramatic impact on patients\u27 well-being. We suggest routine surveillance to identify errors, support for patients who have experienced errors, and implementation of patient and provider checklists to enhance communication. Future studies should investigate strategies to allow care providers adequate time with patients.https://scholarworks.uvm.edu/comphp_gallery/1246/thumbnail.jp

Spotlight on Open Educational Resources: Promoting Low-Cost Solutions for Student Course Materials

Poster for event where CWU Professor Sterling Quinn and Librarian Maura Valentino discuss incorporating OERs into course materials.https://digitalcommons.cwu.edu/libraryevents/1234/thumbnail.jp

On the assessment of pedestrian distress in urban winds

Urban winds can cause a risk to pedestrian safety if not properly assessed. High-rise buildings produce a complex flow field at ground level, where regions of accelerated and recirculating flows are present. Gust wind speeds provide an indication of the maximal speed pedestrian might experience due to the unsteady flow. In this study, low- and high-fidelity numerical and experimental techniques to predict pedestrian level winds are tested on a realistic full-scale test-route at the University of Birmingham Campus during a storm event. Results show that it is beneficial to increase the complexity of simulations as a direct correspondence exists between the gust wind speed and the turbulent environment. While not much gain is achieved switching from Irwin Probes to hot-wire anemometry, LES greatly outperforms RANS and challenges experimental simulations in terms of reliability. The validity of the peak factor is also questioned and a general comment on the adequacy of each technique is discussed

Trains in crosswinds – comparison of full-scale on-train measurements, physical model tests and CFD calculations

In this paper a major series of experiments is described that included extensive full-scale measurements of cross wind induced pressures on the Class 43 New Measurement Train over an extended 21 month period, together with wind tunnel, moving model tests and CFD calculations, and allows, for the first time, a proper evaluation of the adequacy of these techniques. Static wind tunnel tests and moving model tests show good agreement with each other, both in terms of the measured pressure field around the train and in the overall side force per unit length over the yaw angle range from 15 to 30°. Similarly the wind tunnel tests and the CFD calculations show good agreement with each other for yaw angles up to 15°. Two different analyses of the full-scale data were carried out - an analysis of 1 s average wind speeds and forces, and an analysis of specific gusts. There was a very great deal of scatter in the results and only the results from simple track topographies were found to agree well with the model and computational results

Transient aerodynamic pressures and forces on trackside and overhead structures due to passing trains. Part 1 Model scale experiments Part 2 Standards applications

This is the first part of a two-part paper that describes the results of an experimental investigation to measure the aerodynamic pressure forces on structures in the vicinity of railway tracks. The investigations were carried out in order to obtain a fundamental understanding of the nature of the phenomenon and to obtain data for a variety of railway infrastructure geometries of particular relevance to the UK situation, in order to provide material for a National Annex to the relevant Eurocode. The experiments were carried out on the moving model TRAIN Rig, with models of three different sorts of trains with different nose types, and a variety of infrastructures types: vertical hoardings, overbridges, station canopies and trestle platforms. The transient loads that were measured had a characteristic form: a positive pressure peak followed by a negative pressure peak. In general the magnitudes of the two peaks were different, and varied with infrastructure type and position, as well as with train type. As would be expected, the more streamlined the train, the lower were the magnitudes of the pressure transients. A comparison of the experimental results was made with a variety of existing model- scale and full-scale data and a broad consistency was demonstrated, within the limits that the rather different experimental conditions in the various cases would allow. An analysis of the scaling of these pressure transients was carried out, and it was shown that whilst there was a reasonable coalescence around a theoretical formulation, the complexity of the flows involved meant that a general scaling formulation could not be achieved. Part 2 of this paper will consider the application of the results to the development of revised standards formulations. </jats:p