420 research outputs found

    High temperature glass thermal control structure and coating

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    A high temperature stable and solar radiation stable thermal control coating is described which is useful either as such, applied directly to a member to be protected, or applied as a coating on a re-usable surface insulation (RSI). It has a base coat layer and an overlay glass layer. The base coat layer has a high emittance, and the overlay layer is formed from discrete, but sintered together glass particles to give the overlay layer a high scattering coefficient. The resulting two-layer space and thermal control coating has an absorptivity-to-emissivity ratio of less than or equal to 0.4 at room temperature, with an emittance of 0.8 at 1200 F. It is capable of exposure to either solar radiation or temperatures as high as 2000 F without significant degradation. When used as a coating on a silica substrate to give an RSI structure, the coatings of this invention show significantly less reduction in emittance after long term convective heating and less residual strain than prior art coatings for RSI structures

    Reusable silica surface-insulation material

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    Material was specifically developed for manufacture of insulating tiles, but it can be molded into other shapes as required. Basic raw materials are high-purity silica fiber, fumed-silica powder, and reagent-grade starch. Only purest materials are used, and care must be taken to avoid contamination during processing

    Fibrous refractory composite insulation

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    A refractory composite insulating material was prepared from silica fibers and aluminosilicate fibers in a weight ratio ranging from 1:19 to 19:1, and about 0.5 to 30% boron oxide, based on the total fiber weight. The aluminosilicate fiber and boron oxide requirements may be satisfied by using aluminoborosilicate fibers and, in such instances, additional free boron oxide may be incorporated in the mix up to the 30% limit. Small quantities of refractory opacifiers, such as silicon carbide, may be also added. The composites just described are characterized by the absence of a nonfibrous matrix

    Silica reusable surface insulation

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    A reusable silica surface insulation material is provided by bonding amorphous silica fibers with colloidal silica at an elevated temperature. The surface insulation is ordinarily manufactured in the form of blocks (i.e., tiles)

    Reaction cured glass and glass coatings

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    The invention relates to reaction cured glass and glass coatings prepared by reacting a compound selected from the group consisting of silicon tetraboride, silicon hexaboride, other boron silicides, boron and mixtures with a reactive glass frit composed of a porous high silica borosilicate glass and boron oxide. The glassy composites of the present invention are useful as coatings on low density fibrous porous silica insulations used as heat shields and for articles such as reaction vessels that are subjected to high temperatures with rapid heating and cooling and that require resistance to temperature and repeated thermal shock at temperatures up to about 1482C (2700PF)

    Adjustable high emittance gap filler

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    A flexible, adjustable refractory filler is disclosed for filling gaps between ceramic tiles forming the heat shield of a space shuttle vehicle, to protect its aluminum skin during atmospheric reentry. The easily installed and replaced filler consists essentially of a strip of ceramic cloth coated, at least along both its longitudinal edges with a room temperature vulcanizable silicone rubber compound with a high emittance colored pigment. The filler may have one or more layers as the gap width requires. Preferred materials are basket weave aluminoborosilicate cloth, and a rubber compounded with silicon tetraboride as the emittance agent and finely divided borosilicate glass containing about 7.5% B2O3 as high temperature binder. The filler cloth strip or tape is cut to proper width and length, inserted into the gap, and fastened with previously applied drops of silicone rubber adhesive

    What Your Radiologist Might be Missing: Using Machine Learning to Identify Mislabeled Instances of X-ray Images

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    Label quality is an important and common problem in contemporary supervised machine learning research. Mislabeled instances in a data set might not only impact the performance of machine learning models negatively but also make it more difficult to explain, and thus trust, the predictions of those models. While extant research has especially focused on the ex-ante improvement of label quality by proposing improvements to the labeling process, more recent research has started to investigate the use of machine learning-based approaches to identify mislabeled instances in training data sets automatically. In this study, we propose a two-staged pipeline for the automatic detection of potentially mislabeled instances in a large medical data set. Our results show that our pipeline successfully detects mislabeled instances, helping us to identify 7.4% of mislabeled instances of Cardiomegaly in the data set. With our research, we contribute to ongoing efforts regarding data quality in machine learning

    What Your Radiologist Might be Missing: Using Machine Learning to Identify Mislabeled Instances of X-ray Images

    Get PDF
    Label quality is an important and common problem in contemporary supervised machine learning research. Mislabeled instances in a data set might not only impact the performance of machine learning models negatively but also make it more difficult to explain, and thus trust, the predictions of those models. While extant research has especially focused on the ex-ante improvement of label quality by proposing improvements to the labeling process, more recent research has started to investigate the use of machine learning-based approaches to identify mislabeled instances in training data sets automatically. In this study, we propose a two-staged pipeline for the automatic detection of potentially mislabeled instances in a large medical data set. Our results show that our pipeline successfully detects mislabeled instances, helping us to identify 7.4% of mislabeled instances of Cardiomegaly in the data set. With our research, we contribute to ongoing efforts regarding data quality in machine learning

    Fenoldapam for Acute Kidney Injury in Children

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    We report two cases of children with severe cardiomyopathy requiring treatment with ventricular assist devices who developed acute kidney injury and were treated with fenoldopam. Therapy with fenoldopam appeared successful in one case in that renal replacement therapy was avoided with improvement in urine output and renal function. These are the first reported cases of fenoldopam use in children with acute kidney injury receiving mechanical circulatory support

    Nonsteroidal Anti-Inflammatory Drugs Are an Important Cause of Acute Kidney Injury in Children

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    Objective To characterize nonsteroidal anti-inflammatory drug (NSAID)-associated acute kidney injury (AKI) in children. Study design We conducted a retrospective chart review of children diagnosed with AKI through the use of International Classification of Diseases, Ninth Revision diagnosis code 584.5 or 584.9 from January 1999 to June 2010. Medical records were reviewed to confirm the diagnosis of AKI and to quantify NSAID administration. Pediatric RIFLE criteria were used to codify AKI. Patients were not classified as having NSAID-associated AKI if they had a diagnosis explaining AKI or comorbid clinical conditions predisposing to AKI development. Results Patients (N = 1015) were identified through International Classification of Diseases, Ninth Revision screening. Twenty-one children had clinical, laboratory, and radiographic studies suggesting NSAID-associated acute tubular necrosis and 6 had findings suggesting NSAID-associated acute interstitial nephritis, representing 2.7% (27 of 1015) of the total cohort with AKI and 6.6% when excluding complex patients with multifactorial AKI. Children with NSAID-associated AKI had a median (range) age of 14.7 years (0.5-17.7 years); 4 patients (15%) were (75%) for whom dosing data were available received NSAIDs within recommended dosing limits. Patients (100% vs 0%, P \u3c .001), intensive care unit admission (75% vs 9%, P = .013), and a longer length of stay (median 10 vs 7 days, P = .037). Conclusions NSAID-associated AKI accounted for 2.7% of AKI in this pediatric population. AKI typically occurred after the administration of correctly dosed NSAIDs. Young children with NSAID-associated AKI may have increased disease severity
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