7 research outputs found

    Puffer: Pop-Up Flat Folding Explorer Robot

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    A repeatably reconfigurable robot, comprising at least two printed circuit board (PCB) rigid sections, at least one PCB flexible section coupled to the at least two PCB rigid sections, at least one wheel, hybrid wheel propeller, wheel and propeller, or hybrid wheel screw propeller rotatably coupled to at least one of the at least two PCB rigid sections and at least one actuator coupled to the at least two PCB rigid sections, wherein the at least one actuator folds and unfolds the repeatably reconfigurable robot

    NeBula: Team CoSTAR's robotic autonomy solution that won phase II of DARPA Subterranean Challenge

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    This paper presents and discusses algorithms, hardware, and software architecture developed by the TEAM CoSTAR (Collaborative SubTerranean Autonomous Robots), competing in the DARPA Subterranean Challenge. Specifically, it presents the techniques utilized within the Tunnel (2019) and Urban (2020) competitions, where CoSTAR achieved second and first place, respectively. We also discuss CoSTARÂżs demonstrations in Martian-analog surface and subsurface (lava tubes) exploration. The paper introduces our autonomy solution, referred to as NeBula (Networked Belief-aware Perceptual Autonomy). NeBula is an uncertainty-aware framework that aims at enabling resilient and modular autonomy solutions by performing reasoning and decision making in the belief space (space of probability distributions over the robot and world states). We discuss various components of the NeBula framework, including (i) geometric and semantic environment mapping, (ii) a multi-modal positioning system, (iii) traversability analysis and local planning, (iv) global motion planning and exploration behavior, (v) risk-aware mission planning, (vi) networking and decentralized reasoning, and (vii) learning-enabled adaptation. We discuss the performance of NeBula on several robot types (e.g., wheeled, legged, flying), in various environments. We discuss the specific results and lessons learned from fielding this solution in the challenging courses of the DARPA Subterranean Challenge competition.The work is partially supported by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004), and Defense Advanced Research Projects Agency (DARPA)

    Analysis of fetal biometric measurements in the last 30 years

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    Objectives. To compare fetal biometric measurements with standard growth charts for ultrasound parameters existing from the last 30 years. Study design. A preliminary prospective study. Setting. Artemisia Mean Centre of Perinatal Diagnosis, Rome, Italy. Material and method. A cross sectional study involving 1000 pregnant women with uncomplicated singleton pregnancy between 14th and 41th weeks of gestation from 1 January to 30 June 2008. All recruited pregnant women enrolled had an abdominal ultrasonography for fetal biometry. For each measurement, regression models were fitted to estimate the mean and SD. The results were compared with existing references from the last 30 years using Student’s T distribution. Moreover, neonatal weights were obtained from 1977 to 2008 by ISTAT. Results. One thousand normal fetuses from pregnant women, between 22th and 23th weeks, between 32th and 33th weeks and at 38th week, were thoroughly measured. There were significant differences from the comparison with our data for each gestational age: femur length and homer length, abdominal circumference, head circumference and occipito-frontal diameter were longer than all parameters of existing references from the last 30 years. The analysis of neonatal weights on ISTAT data from 1977 to 2007 demonstrated a significant increment through the years. Conclusion. Fetus is grown up across the years. It is necessary to modify the standard growth charts for ultrasound parameters existing from the last 30 years with actually fetal biometric measurements. It is helpful for a correct clinical approach and for an appropriate management mother-fetus

    Prognostic Significance of PET/CT in Patients with Chronic Lymphocytic Leukemia (CLL) Treated with Frontline Chemoimmunotherapy

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    The role of positron emission tomography/computed tomography (PET/CT) in identifying Richter Syndrome (RS) is well established, while its impact on the survival of patients with chronic lymphocytic leukemia (CLL) has been less explored. The clinical characteristics and PET/CT data of 40 patients with a biopsy-proven CLL who required frontline chemoimmunotherapy, FCR (fludarabine, cyclophosphamide, rituximab) in 20 patients, BR (bendamustine, rituximab) in 20, were retrospectively analyzed. Standardized uptake volume (SUVmax) values ≥ 5 were observed more frequently in patients with deletion 11q (p = 0.006) and biopsies characterized by a rate of Ki67 positive cells ≥ 30% (p = 0.02). In the multivariate analysis, the presence of large and confluent PCs emerged as the only factor with a negative impact on progression-free survival (PFS), and overall survival (OS). Deletion 11q also revealed a significant and independent effect on PFS. SUVmax values ≥ 5 showed no statistical impact on PFS while in multivariate analysis, they revealed a significant adverse impact on OS (median survival probability not reached vs. 56 months; p = 0.002). Moreover, patients with higher SUVmax values more frequently developed Richter Syndrome (p = 0.015). Our results show that higher SUVmax values identify CLL patients with a pronounced rate of proliferating cells in the lymph-node compartment, inferior survival, and an increased risk of developing RS

    Search for intermediate-mass black hole binaries in the third observing run of Advanced LIGO and Advanced Virgo

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    International audienceIntermediate-mass black holes (IMBHs) span the approximate mass range 100−105 M⊙, between black holes (BHs) that formed by stellar collapse and the supermassive BHs at the centers of galaxies. Mergers of IMBH binaries are the most energetic gravitational-wave sources accessible by the terrestrial detector network. Searches of the first two observing runs of Advanced LIGO and Advanced Virgo did not yield any significant IMBH binary signals. In the third observing run (O3), the increased network sensitivity enabled the detection of GW190521, a signal consistent with a binary merger of mass ∌150 M⊙ providing direct evidence of IMBH formation. Here, we report on a dedicated search of O3 data for further IMBH binary mergers, combining both modeled (matched filter) and model-independent search methods. We find some marginal candidates, but none are sufficiently significant to indicate detection of further IMBH mergers. We quantify the sensitivity of the individual search methods and of the combined search using a suite of IMBH binary signals obtained via numerical relativity, including the effects of spins misaligned with the binary orbital axis, and present the resulting upper limits on astrophysical merger rates. Our most stringent limit is for equal mass and aligned spin BH binary of total mass 200 M⊙ and effective aligned spin 0.8 at 0.056 Gpc−3 yr−1 (90% confidence), a factor of 3.5 more constraining than previous LIGO-Virgo limits. We also update the estimated rate of mergers similar to GW190521 to 0.08 Gpc−3 yr−1.Key words: gravitational waves / stars: black holes / black hole physicsCorresponding author: W. Del Pozzo, e-mail: [email protected]† Deceased, August 2020
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