3,772 research outputs found

    Railroads and the Making of Modern America -- Tools for Spatio-Temporal Correlation, Analysis, and Visualization

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    This project aims to integrate large-scale data sources from the Digging into Data repositories with other types of relevant data on the railroad system, already assembled by the project directors. Our project seeks to develop useful tools for spatio-temporal visualization of these data and the relationships among them. Our interdisciplinary team includes computer science, history, and geography researchers. Because the railroad "system" and its spatio-temporal configuration appeared differently from locality-to-locality and region-to-region, we need to adjust how we "locate" and "see" the system. By applying data mining and pattern recognition techniques, software systems can be created that dynamically redefine the way spatial data are represented. Utilizing processes common to analysis in Computer Science, we propose to develop a software framework that allows these embedded concepts to be visualized and further studied

    Water levels in artesian and nonartesian aquifers of Florida, 1971-72

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    The Department of Natural Resources, Bureau of Geology, is publishing as its Information Circular No. 85 the report entitled, "Water Levels in Artesian and Non-Artesian Aquifers of Florida, 1971-72," by Henry G. Healy, of the U. S. Geological Survey. In order to prevent future shortages developing from increasing demands, the present supplies of ground water must be properly appraised before they can be effectively utilized. Records of trends and fluctuations of ground water have long formed a basis for such an appraisal. (105 page document

    John S. Mbiti (1931-2019)

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    TRIBUTE TO JOHN S. MBITI (30 November 1931 - 6 October 2019

    John S. Mbiti (1931-2019)

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    TRIBUTE TO JOHN S. MBITI (30 November 1931 - 6 October 2019

    Desert locust populations, rainfall and climate change: insights from phenomenological models using gridded monthly data

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    Using autocorrelation analysis and autoregressive integrated moving average (ARIMA)modelling, we analysed a time series of the monthly number of 1° grid squares infested with desert locust Schistocerca gregaria swarms throughout the geographical range of the species from 1930–1987. Statistically significant first- and higher-order autocorrelations were found in the series. Although endogenous components captured much of the variance, adding rainfall data improved endogenous ARIMA models and resulted in more realistic forecasts. Using a square-root transformation for the locust data improved the fit. The models were only partially successful when accounting for the dramatic changes in abundance which may occur during locust upsurges and declines, in some cases successfully predicting these phenomena but underestimating their severity. Better fitting models were also produced when rainfall data were added to models of an equivalent series for desert locust hoppers (nymphs) that incorporated lagged data for locust swarms as independent variables, representing parent generations. The results are discussed in relation to predicting likely changes in desert locust dynamics with reference to potential effects of climate change

    Tribute to John S. Mbiti

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    We continue to mourn John S. Mbiti, the Kenyan professor, author and theologian who died in Switzerland on 6 October, 2019 at the age of 87. He was one of the founders of our African Proverbs Project and the African Proverbs Working Group. He was one of cornerstones of our African Proverbs, Sayings and Stories Website

    A Statistical Description of AGN Jet Evolution from the VLBA Imaging and Polarimetry Survey (VIPS)

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    A detailed analysis of the evolution of the properties of core-jet systems within the VLBA Imaging and Polarimetry Survey (VIPS) is presented. We find a power-law relationship between jet intensity and width that suggests for the typical jet, little if any energy is lost as it moves away from its core. Using VLA images at 1.5 GHz, we have found evidence that parsec-scale jets tend to be aligned with the the direction of emission on kiloparsec scales. We also found that this alignment improves as the jets move farther from their cores on projected scales as small as ~50-100 pc. This suggests that realignment of jets on these projected scales is relatively common. We typically find a modest amount of bending (a change in jet position angle of ~5 deg.) on these scales, suggesting that this realignment may typically occur relatively gradually.Comment: Accepted to ApJ, 20 pages, 8 figure

    Technology for an intelligent, free-flying robot for crew and equipment retrieval in space

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    Crew rescue and equipment retrieval is a Space Station Freedom requirement. During Freedom's lifetime, there is a high probability that a number of objects will accidently become separated. Members of the crew, replacement units, and key tools are examples. Retrieval of these objects within a short time is essential. Systems engineering studies were conducted to identify system requirements and candidate approaches. One such approach, based on a voice-supervised, intelligent, free-flying robot was selected for further analysis. A ground-based technology demonstration, now in its second phase, was designed to provide an integrated robotic hardware and software testbed supporting design of a space-borne system. The ground system, known as the EVA Retriever, is examining the problem of autonomously planning and executing a target rendezvous, grapple, and return to base while avoiding stationary and moving obstacles. The current prototype is an anthropomorphic manipulator unit with dexterous arms and hands attached to a robot body and latched in a manned maneuvering unit. A precision air-bearing floor is used to simulate space. Sensor data include two vision systems and force/proximity/tactile sensors on the hands and arms. Planning for a shuttle file experiment is underway. A set of scenarios and strawman requirements were defined to support conceptual development. Initial design activities are expected to begin in late 1989 with the flight occurring in 1994. The flight hardware and software will be based on lessons learned from both the ground prototype and computer simulations

    A comparison between phone-based psychotherapy with and without text messaging support in between sessions for crisis patients

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    BACKGROUND: Few studies have tested whether individually tailored text messaging interventions have an effect on clinical outcomes when used to supplement traditional psychotherapy. This is despite the potential to improve outcomes through symptom monitoring, prompts for between-session activities, and psychoeducation. OBJECTIVE: The intent of the study was to explore the use of individually tailored between-session text messaging, or short message service (SMS), as an adjunct to telephone-based psychotherapy for consumers who present to the Emergency Department (ED) in situational and/or emotional crises. METHODS: Over a 4-month period, two therapists offered 68 prospective consumers of a telephone-based psychotherapy service individually tailored between-session text messaging alongside their telephone-based psychotherapy. Attendance and clinical outcomes (depression, anxiety, functional impairment) of those receiving messages were compared against a historical control group (n=157) who received telephone psychotherapy only. RESULTS: A total of 66% (45/68) of the consumers offered SMS accepted the intervention. A total of 432 messages were sent over the course of the trial, the majority involving some kind of psychoeducation or reminders to engage in therapy goals. There were no significant differences in clinical outcomes between consumers who received the SMS and those in the control group. There was a trend for participants in the intervention group to attend fewer sessions than those in the control group (mean 3.7, SD 1.9 vs mean 4.4, SD 2.3). CONCLUSIONS: Both groups showed significant improvement over time. Individually tailored SMS were not found to improve clinical outcomes in consumers receiving telephone-based psychotherapy, but the study was underpowered, given the effect sizes noted and the significance level chosen. Given the ease of implementation and positive feedback from therapists and clients, individually tailored text messages should be explored further in future trials with a focus on enhancing the clinical impact of the tailored text messages, and utilizing designs with additional power to test for between-group effects.Gareth Furber, Gabrielle Margaret Jones, David Healey, Niranjan Bidargadd
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