318 research outputs found

    DBL SmartCity: An Open-Source IoT Platform for Managing Large BIM and 3D Geo-Referenced Datasets

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    The `smart city\u27 approach has been promoted as an effective way to manage urban environments. Information and communication technology in general, as well as `Internet of Things\u27 systems in particular, constitute an essential component of all smart city initiatives. However, many past and current smart city implementations place only an insufficient emphasis on the geo-spatial and 3D nature of data. In order to fill this gap, we present DBL SmartCity, an open-source smart city IoT platform that is based on open standards and designed from the ground-up to effectively store, manage, and present large sets of BIM and 3D geo-referenced data

    The Evolution and Changing Context of Social Work Education

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    The nature of social work education has changed dramatically over the course of my academic career: From the degree(s) required for a faculty position to the number of years of practice experience; from expectations for research and publication, to criteria for promotion and tenure; from residential instruction to distance education; from an emphasis on foundation curriculum to practice competencies and outcomes; and, from a commitment to service to a quest to be the highest “ranked” program within the highest ranked institution. Given that change is an ongoing phenomenon, it is difficult to anticipate curriculum direction or plan one’s career path with a high degree of certainty. The future is often determined by external events, fate, where you are at a specific time, the assistance of others, and the opportunities that are presented. These changes and the evolution of social work education as a field of professional practice can best be demonstrated by reflecting on my own experiences in becoming a faculty member and serving in various academic positions over the last 45 years. The contrast between my personal experiences and those of the typical student in 2014 may help demonstrate some of the changes that have occurred in social work education over the intervening years

    Crop root system plasticity for improved yields in saline soils.

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    Crop yields must increase to meet the demands of a growing world population. Soil salinization is increasing due to the impacts of climate change, reducing the area of arable land for crop production. Plant root systems are plastic, and their architecture can be modulated to (1) acquire nutrients and water for growth, and (2) respond to hostile soil environments. Saline soils inhibit primary root growth and alter root system architecture (RSA) of crop plants. In this review, we explore how crop root systems respond and adapt to salinity, focusing predominately on the staple cereal crops wheat, maize, rice, and barley, that all play a major role in global food security. Cereal crops are classified as glycophytes (salt-sensitive) however salt-tolerance can differ both between species and within a species. In the past, due to the inherent difficulties associated with visualising and measuring root traits, crop breeding strategies have tended to focus on optimising shoot traits. High-resolution phenotyping techniques now make it possible to visualise and measure root traits in soil systems. A steep, deep and cheap root ideotype has been proposed for water and nitrogen capture. Changes in RSA can be an adaptive strategy to avoid saline soils whilst optimising nutrient and water acquisition. In this review we propose a new model for designing crops with a salt-tolerant root ideotype. The proposed root ideotype would exhibit root plasticity to adapt to saline soils, root anatomical changes to conserve energy and restrict sodium (Na+) uptake, and transport mechanisms to reduce the amount of Na+ transported to leaves. In the future, combining high-resolution root phenotyping with advances in crop genetics will allow us to uncover root traits in complex crop species such as wheat, that can be incorporated into crop breeding programs for yield stability in saline soils.Megan C. Shelden, and Rana Munn

    Communications technologies in collaborative design

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997.Includes bibliographical references (leaves 76-78).by Dennis R. Shelden.M.S

    Dynamic Density: An Air Traffic Management Metric

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    The definition of a metric of air traffic controller workload based on air traffic characteristics is essential to the development of both air traffic management automation and air traffic procedures. Dynamic density is a proposed concept for a metric that includes both traffic density (a count of aircraft in a volume of airspace) and traffic complexity (a measure of the complexity of the air traffic in a volume of airspace). It was hypothesized that a metric that includes terms that capture air traffic complexity will be a better measure of air traffic controller workload than current measures based only on traffic density. A weighted linear dynamic density function was developed and validated operationally. The proposed dynamic density function includes a traffic density term and eight traffic complexity terms. A unit-weighted dynamic density function was able to account for an average of 22% of the variance in observed controller activity not accounted for by traffic density alone. A comparative analysis of unit weights, subjective weights, and regression weights for the terms in the dynamic density equation was conducted. The best predictor of controller activity was the dynamic density equation with regression-weighted complexity terms
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