A Gaussian Integral Filter with Multivariate Laplace Process Noise

This paper introduces the concept of the Gaussian integral filter (GIF), the limit of the Gaussian sum filter (GSF) for when the number of mixands tends to infinity. The GIF is obtained via a combination of GSF, quadrature, and interpolation. While it is a very general concept, in this paper the GIF is used to represent multiviariate Laplace (ML) distributions defining the process noise when tracking a maneuvering target. The filter is first applied to a linear three-dimensional toy problem, and then to a maneuvering target tracking problem in Earth orbit. For the more complex maneuvering target tracking problem, the filter requires only 1.4 times the computational resources of an unscented Kalman filter (UKF), while having errors up to 11 times smaller. For the same problem, the UKF slowly diverges.Comment: IEEE International Conference on Information Fusion, Charleston, SC, U.S.A., June 27-30, 202

Polarization Requirements for Ensemble Implementations of Quantum Algorithms with a Single Bit Output

We compare the failure probabilities of ensemble implementations of quantum algorithms which use pseudo-pure initial states, quantified by their polarization, to those of competing classical probabilistic algorithms. Specifically we consider a class algorithms which require only one bit to output the solution to problems. For large ensemble sizes, we present a general scheme to determine a critical polarization beneath which the quantum algorithm fails with greater probability than its classical competitor. We apply this to the Deutsch-Jozsa algorithm and show that the critical polarization is 86.6%.Comment: 11 pages, 3 figure

An Imaging Technique for Safe Spacecraft Landing and Autonomous Hazard Avoidance

©2006 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.Presented at SMC-IT 2006, 2nd IEEE International Space Mission Challenges for Information Technology,17-20 July 2006, Pasadena, California.DOI: 10.1109/SMC-IT.2006.15The focus of this paper is to present an image transformation algorithm to interpret historical imagery land data for autonomous safe landing of a robotic spacecraft. Inherent geographical hazards of Martian terrain may impede safe landing for a science exploration spacecraft. Surface visualization software for hazard detection and avoidance may therefore be applied to enable an autonomous and intelligent spacecraft descent upon entering the planetary atmosphere. The methodology proposed involves integrating linear algebra and computer vision/graphics techniques, with the intrinsic parameters governing spacecraft dynamic motion and camera calibration, in order to assess hazards that might impede spacecraft landing. In this paper, we provide algorithmic details and simulation results of our methodology applied to a representative Mars landing descent profile

Real-world, multicentre evaluation of the incidence and risk factors for non-susceptible Stenotrophomonas maltophilia isolates

Background: Stenotrophomonas maltophilia is a cause of infection most commonly in the opportunistic host. Trimethoprim-sulfamethoxazole and levofloxacin are considered first-line treatment agents. With reports of increasing resistance to these first-line agents, it is important to determine risk factors associated with a non-susceptible isolate. Methods: This was a real-world, multicentre, retrospective case-control study from five centres in the southeast United States evaluating S. maltophilia. The primary outcome was risk factors associated with non-susceptibility of S. maltophilia isolates to ≥1 antimicrobial agents. Secondary outcomes include incidence of S. maltophilia non-susceptibility, all-cause mortality, and 30-day readmission rates. Results: There were 325 patients included in the study. For the primary outcome, the only factor associated with non-susceptibility per univariate analysis was isolation from urine culture (13.3% vs. 5.4%; P = 0.014), whereas the presence of mechanical ventilation (37.7% vs. 21.5%) and intensive care unit admission (35.3% vs. 18.4%) were associated with susceptibility (P \u3c 0.001). For the secondary outcomes, non-susceptibility was present in 49% of isolates with 43 of 325 (13.2%), 53 of 324 (16.4%), and 105 of 172 (61%) to TMP-SMX, levofloxacin, and ceftazidime, respectively. Resistance to chloramphenicol and tigecycline was observed among 5/26 and 11/16 of tested isolates, respectively. Sixty-six patients (20%) experienced all-cause, inpatient mortality (18% susceptible vs. 23% non-susceptible; P = 0.280) and 44 patients (17%) were readmitted within 30 days of discharge (16% susceptible vs. 18% non-susceptible; P = 0.673). Conclusion: S. maltophilia non-susceptibility had a prevalence of ∼50% to at least one first-line or commonly used agent. More research is needed to delineate risk factors for non-susceptible isolates

Growth and persistence of 17 annual medic (Medicago spp.) accessions on clay soils in central Queensland

Seventeen accessions of annual medics were evaluated on clay soil sites at Emerald, Theodore, Biloela and Mundubbera, central Queensland. Successful medics could have a role in both permanent and ley pastures. However, these are marginal areas for medics with winter (June-August) rainfalls of 80-100 mm. The accessions were selected on the basis of results in southern Queensland, a more favoured area for medics. There were 9 accessions of Medicago truncatula (barrel medic), 4 of M. scutellata (snail medic), 2 of M. polymorpha (burr medic) and 1 each of M. aculeata (keg medic) and M. orbicularis (button medic). Lucerne (M. sativa) cv. Trifecta was sown at 3 sites. All sites except Theodore were irrigated in the year of establishment (1993). The medic seedlings at Theodore died in 1993 and the trial was resown in 1994. Measurements were made of seed set in the first year and whenever it occurred in later years, seedling density in most years and yield when there was adequate growth. Selected measurements were made of soil seed reserves. Measurements ceased in 1998

Using Bayesian multispecies models to evaluate fish and invertebrate detection probability and distribution in the hypersaline Bahia Grande tidal basin

Objective In 2000, the Laguna Atascosa National Wildlife Refuge acquired the Bahia Grande (Texas) management unit, a space that had lain barren and arid for 70 years. A large cooperative partnership launched a restoration project to replenish the basin and recover its original tidal hydrology. In 2005, the construction of a pilot channel successfully restored water throughout the basin, and plans to eventually widen the channel were developed. Our study aims to evaluate an estuarine habitat restoration by assessing ecological drivers and the impacts on species diversity. Methods We evaluated species richness, detection/occupancy rates, and species–habitat relationships, and we estimated the sampling effort required to achieve a given level of relative precision if relative abundance was used instead of occupancy to inform future sampling. Sampling gear included bag seines for juvenile life stages and gill nets for capturing subadult and adult life stages. For analysis, we used a Bayesian negative binomial linear mixed-effects model to evaluate richness–habitat relationships and a hierarchical Bayesian multispecies model to evaluate individual species–habitat relationships, and we calculated the total number of fish captured and relative standard error by gear and sample year to produce a precise estimate of relative abundance. Result Overall, 29 species were caught between 2018 and 2021. Salinity emerged as a clear driver in the Bahia Grande, as both species richness and individual-level responses were negatively associated with high salinity values. We found that catch estimated as relative abundance had much variability, as is typical of most survey programs assuming constant detectability, and the number of net sets or seine hauls required to achieve a given level of relative precision varied considerably depending on the species, season, year, and gear type. The most collected species were found in the upper extremes of their salinity tolerances—potentially a unique adaptation to this hypersaline system. Conclusion Baseline data suggest that for the channel widening to be successful, there must be a noticeable increase in suitable habitat characteristics throughout the basin. Impact statement Habitat restoration is a unique opportunity to assess changes in aquatic communities. We used hierarchical Bayesian models to describe prerestoration community relationships for one of the largest coastal restorations in Texas. This flexible framework can be applied to other complex habitat restorations

Neutrinos and Gamma Rays from Galaxy Clusters

The next generation of neutrino and gamma-ray detectors should provide new insights into the creation and propagation of high-energy protons within galaxy clusters, probing both the particle physics of cosmic rays interacting with the background medium and the mechanisms for high-energy particle production within the cluster. In this paper we examine the possible detection of gamma-rays (via the GLAST satellite) and neutrinos (via the ICECUBE and Auger experiments) from the Coma cluster of galaxies, as well as for the gamma-ray bright clusters Abell 85, 1758, and 1914. These three were selected from their possible association with unidentified EGRET sources, so it is not yet entirely certain that their gamma-rays are indeed produced diffusively within the intracluster medium, as opposed to AGNs. It is not obvious why these inconspicuous Abell-clusters should be the first to be seen in gamma-rays, but a possible reason is that all of them show direct evidence of recent or ongoing mergers. Their identification with the EGRET gamma-ray sources is also supported by the close correlation between their radio and (purported) gamma-ray fluxes. Under favorable conditions (including a proton spectral index of 2.5 in the case of Abell 85, and sim 2.3 for Coma, and Abell 1758 and 1914), we expect ICECUBE to make as many as 0.3 neutrino detections per year from the Coma cluster of galaxies, and as many as a few per year from the Abell clusters 85, 1758, and 1914. Also, Auger may detect as many as 2 events per decade at ~ EeV energies from these gamma-ray bright clusters.Comment: Accepted for publication in Ap

Consuming Lines of Difference: The Politics of Wealth and Poverty along the Color Line

Commentators on African American life have often focused on poverty, evaded African American wealth, and ignored the ways genteel affluence and impoverishment were constructed along turn-of-the-century color lines. Documentary research and archaeology at the Madam CJ Walker home in Indianapolis, Indiana illuminates how the continuum of wealth and poverty was defined and negotiated by one of African America’s wealthiest early 20th century entrepreneurs. The project provides an opportunity to compare the ways in which wealth was defined and experienced along the color line in the early 20th century and how such notions of Black affluence shaped racialized definitions of poverty and materialit