17 research outputs found

    Enabling High-Power SmallSats with Advanced Thermal Management

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    High-power Small Satellites have the potential to provide new and advanced capabilities; however, significant challenges prevent wide-spread use. Of these, thermal management of high-heat loads is significant. Although advances in thermal acquisition, transport, and storage are available; thermal dissipation technologies for high-power systems are lacking. Several design concepts are presented focused on high-efficiency, lightweight deployable radiating technologies. Analysis showed that realistic deployable radiator designs offer 220% more thermal dissipation than body-mounted radiator designs, which directly correlates to the same amount of increase in feasible total bus power. Using deployable radiators, a nominal 6U Small Satellite can realistically dissipate around 200 W

    Using Additive Manufacturing to Print a CubeSat Propulsion System

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    Small satellites, such as CubeSats, are increasingly being called upon to perform missions traditionally ascribed to larger satellite systems. However, the market of components and hardware for small satellites, particularly CubeSats, still falls short of providing the necessary capabilities required by ever increasing mission demands. One way to overcome this shortfall is to develop the ability to customize every build. By utilizing fabrication methods such as additive manufacturing, mission specific capabilities can be built into a system, or into the structure, that commercial off-the-shelf components may not be able to provide. A partnership between the University of Texas at El Paso, COSMIAC at the University of New Mexico, Northrop Grumman, and the NASA Glenn Research Center is looking into using additive manufacturing techniques to build a complete CubeSat, under the Small Spacecraft Technology Program. The W. M. Keck Center at the University of Texas at El Paso has previously demonstrated the ability to embed electronics and wires into the addtively manufactured structures. Using this technique, features such as antennas and propulsion systems can be included into the CubeSat structural body. Of interest to this paper, the team is investigating the ability to take a commercial micro pulsed plasma thruster and embed it into the printing process. Tests demonstrating the dielectric strength of the printed material and proof-of-concept demonstration of the printed thruster will be shown

    Environmental pollution with oil-products in the refinery area

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    Niekontrolowane wycieki węglowodorów są istotną ingerencją w środowisko gruntowe. Hamują one wymianę gazową, ograniczają dostęp światła, zmniejszają stężenie rozpuszczonego tlenu, zanieczyszczają glebę i grunty, zaburzają homeostazę, a przede wszystkim mają działanie toksyczne, mutagenne i kancerogenne na wszystkie organizmy żywe. W artykule przedstawiono wyniki badań stanu jakościowego środowiska gruntowego w rejonie instalacji petrochemicznych w zakresie zawartości w nich węglowodorów. Na podstawie porównania wyników badań geochemicznych do wartości progowych zawartych w rozporządzeniu Ministra Środowiska dotyczących standardów jakości gleby i ziemi stwierdzono, że gleby i grunty na terenach rafineryjnych są zanieczyszczone substancjami ropopochodnymi ponad dopuszczalne wartości, co kwalifikuje je do oczyszczania.Uncontrolled seepages of hydrocarbons significantly affect the ground environment. They hinder gaseous exchange, limit access of the light, reduce concentration of dissolved oxygen, contaminated the soil and ground, disturb homeostasis, and before all - are toxic, mutagenic and cancerous to all living organisms. The results of analyses of the qualitative state of ground environment in the area of petrochemic installations on hydrocarbon content are presented in the paper. Basing on the comparison of geochemical analyses and threshold values in the Regulation about soil and ground standards of the Minister of Environment it was stated that soils and grounds in the refinery areas were polluted with oil-products. The admissible concentrations were exceeded, and thus the grounds were qualified to the treatment programs

    Mapping never-never land: An examination of pinson mounds cartography

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    The well-known map of the Pinson Mounds site published by William Myer in 1922 illustrates numerous earthworks, including 34 mounds and extensive embankments, most of which are not visible today. Researchers have long debated the existence of these features and the accuracy of Myer\u27s map in general. Using early photographs, topographic maps, gradiometry, and, most important, the 1917 field map upon which the 1922 map was based, it is clear that a number of the mapped features were not visible to Myer and were simply products of his imagination. Furthermore, we provide strong evidence that the Inner Citadel embankment and several associated mounds never existed

    The technical and economical perspectives for the production and storage of hydrogen in Poland

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    This article presents the potential of hydrogen production and storage technology in Poland. The decomposition of fossil fuels (methane reforming using steam, partial methane oxidation, autothermal reforming and coal gasification), decomposition of biological material (biological and thermochemical methods) and nuclear technologies as possible key methods of hydrogen production in Poland are discussed. The total estimated technical potential of hydrogen production was set at 37 million Mg per year nationally. Coal gasification was the most prospective technology. The methods of hydrogen storage in porous materials and polymers were also analyzed. The possibilities of using hydrogen in transport were also presented

    2021 American College of Rheumatology Guideline for the Treatment of Rheumatoid Arthritis

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    Guidelines and recommendations developed and/or endorsed by the American College of Rheumatology (ACR) are intended to provide general guidance for commonly encountered clinical scenarios. The recommendations do not dictate the care for an individual patient. The ACR considers adherence to the recommendations described in this guideline to be voluntary, with the ultimate determination regarding their application to be made by the clinicians in light of each patient’s individual circumstances. Guidelines and recommendations are intended to promote beneficial or desirable outcomes but cannot guarantee any specific outcome. Guidelines and recommendations developed and endorsed by the ACR are subject to periodic revision as warranted by the evolution of medical knowledge, technology, and practice. ACR recommendations are not intended to dictate payment or insurance decisions, or drug formularies or other third-party analyses. Third parties that cite ACR guidelines should state that these recommendations are not meant for this purpose. These recommendations cannot adequately convey all uncertainties and nuances of patient care. The American College of Rheumatology is an independent, professional, medical and scientific society that does not guarantee, warrant, or endorse any commercial product or service. OBJECTIVE. To develop updated guidelines for the pharmacologic management of rheumatoid arthritis. METHODS. We developed clinically relevant population, intervention, comparator, and outcomes (PICO) questions. After conducting a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the certainty of evidence. A voting panel comprising clinicians and patients achieved consensus on the direction (for or against) and strength (strong or conditional) of recommendations. RESULTS. The guideline addresses treatment with disease-modifying antirheumatic drugs (DMARDs), including conventional synthetic DMARDs, biologic DMARDs, and targeted synthetic DMARDs, use of glucocorticoids, and use of DMARDs in certain high-risk populations (i.e., those with liver disease, heart failure, lymphoproliferative disorders, previous serious infections, and nontuberculous mycobacterial lung disease). The guideline includes 44 recommendations (7 strong and 37 conditional). CONCLUSION. This clinical practice guideline is intended to serve as a tool to support clinician and patient decision-making. Recommendations are not prescriptive, and individual treatment decisions should be made through a shared decision-making process based on patients’ values, goals, preferences, and comorbidities
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