1,457 research outputs found

    Lunar beneficiation

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    Natural concentrations of industrially valuable minerals are far less likely to be found on the Moon than on the Earth. But that is all the more reason for devising beneficiation processes to concentrate and extract the useful mineral components in lunar rocks and soils. As an example of a useful mineral that can be beneficiated, it has been estimated that ilmenite abundance accounts for 15 and 20 percent of the volume of the Apollo 11 and 17 basalts and 2 and 5 percent by volume in the Apollo 11 and 17 soils. Reduction of lunar ilmenite with hydrogen imported from Earth appears to one of the more practical schemes for obtaining lunar oxygen. While the reported concentrations are significant, a more highly concentrated ilmenite extract would improve the efficiency of the reduction process. The topics covered include electrostatic concentration, magnetic concentration, lunar soil sizing, and electrical sizing

    Beneficiation and extraction of nonterrestrial materials, part 2

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    A review of options for processing extraterrestrial materials was dominated by industrial materials scientist who tried to identify which processes utilizing space materials could be implemented in the near term. The most practical process seem to us to be the extraction of lunar oxygen and the extraction of metals and ceramics from the residues of the reduction process. The growth of space activity will be accompanied by increased demand for liquid oxygen for each round trip to the Moon. The oxygen and the intermediary product water will be needed for the life support at the base. The reduced metals and ceramics may be considered byproducts or may develop into primary products. Some of the same processes would be directly applicable to recovery of products from asteroids. We also discussed other processes for directly utilizing asteroid metals. Some of the topics covered include beneficiation and oxygen extraction methods, metallurgy, and extraterrestrial cement

    Lunar cement

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    With the exception of water, the major oxide constituents of terrestrial cements are present at all nine lunar sites from which samples have been returned. However, with the exception of relatively rare cristobalite, the lunar oxides are not present as individual phases but are combined in silicates and in mixed oxides. Lime (CaO) is most abundant on the Moon in the plagioclase (CaAl2Si2O8) of highland anorthosites. It may be possible to enrich the lime content of anorthite to levels like those of Portland cement by pyrolyzing it with lunar-derived phosphate. The phosphate consumed in such a reaction can be regenerated by reacting the phosphorus product with lunar augite pyroxenes at elevated temperatures. Other possible sources of lunar phosphate and other oxides are discussed

    Applying default probabilities in an exponential barrier structural model

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    This paper shows that the use of a time-dependant barrier in a structural model improve its flexibility because it allows to incorporate, as input, the probability of default. The main result achieved is the assessment that the default barrier is, indeed,characterized by a non flat structure. JEL Classification: G13, G33default structural models, barrier options with exponential boundaries, implied default probability

    RAPID WEBGIS DEVELOPMENT FOR EMERGENCY MANAGEMENT

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    The use of spatial data during emergency response and management helps to make faster and better decisions. Moreover spatial data should be as much updated as possible and easy to access. To face the challenge of rapid and updated data sharing the most efficient solution is largely considered the use of internet where the field of web mapping is constantly evolving. ITHACA (Information Technology for Humanitarian Assistance, Cooperation and Action) is a non profit association founded by Politecnico di Torino and SITI (Higher Institute for the Environmental Systems) as a joint project with the WFP (World Food Programme). The collaboration with the WFP drives some projects related to Early Warning Systems (i.e. flood and drought monitoring) and Early Impact Systems (e.g. rapid mapping and assessment through remote sensing systems). The Web GIS team has built and is continuously improving a complex architecture based entirely on Open Source tools. This architecture is composed by three main areas: the database environment, the server side logic and the client side logic. Each of them is implemented respecting the MCV (Model Controller View) pattern which means the separation of the different logic layers (database interaction, business logic and presentation). The MCV architecture allows to easily and fast build a Web GIS application for data viewing and exploration. In case of emergency data publication can be performed almost immediately as soon as data production is completed. The server side system is based on Python language and Django web development framework, while the client side on OpenLayers, GeoExt and Ext.js that manage data retrieval and user interface. The MCV pattern applied to javascript allows to keep the interface generation and data retrieval logic separated from the general application configuration, thus the server side environment can take care of the generation of the configuration file. The web application building process is data driven and can be considered as a view of the current architecture composed by data and data interaction tools. Once completely automated, the Web GIS application building process can be performed directly by the final user, that can customize data layers and controls to interact with the

    Monitoring Covid-19 contagion growth in Europe. CEPS Working Document No 2020/03, March 2020

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    We present an econometric model which can be employed to monitor the evolution of the COVID-19 contagion curve. The model is a Poisson autoregression of the daily new observed cases, and can dynamically show the evolution of contagion in different time periods and locations, allowing for the comparative evaluation of policy approaches. We present timely results for nine European countries currently hit by the virus. From the findings, we draw four main conclusions. First, countries experiencing an explosive process (currently France, Italy and Spain), combined with high persistence of contagion shocks (observed in most countries under investigation), require swift policy measures such as quarantine, diffuse testing and even complete lockdown. Second, in countries with high persistence but lower contagion growth (currently Germany) careful monitoring should be coupled with at least “mild” restrictions such as physical distancing or isolation of specific areas. Third, in some countries, such as Norway and Denmark, where trends seem to be relatively under control and depend on daily contingencies, with low persistence, the approach to restrictive measures should be more cautious since there is a risk that social costs outweigh the benefits. Fourth, countries with a limited set of preventive actions in place (such as the Netherlands, Switzerl

    Fighting Segregation, Teaching Multiculturalism: The Beginning of the Education/Instruccion Narrative of the 1970s Hartford Civil Rights Movement

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    In 1970, in the North End of Hartford, Connecticut, a multicultural research action group named Education/Instruccion targeted institutional racism to address issues such as poverty, housing discrimination, and educational opportunity. This historical narrative explores how three activists (Julia Ramos, Ben Dixon, and Boyd Hinds) created the organization in their pursuit of social justice for African-Americans and Puerto Ricans in the city

    Improving Lesbian, Gay, Bisexual, and Transgender Health Care Outcomes

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    Many lesbian, gay, bisexual, and transgender (LGBT) individuals report experiencing discrimination in their health care that leads to avoidance of regular appointments with providers. Lack of regular primary care can delay diagnoses of preventable conditions and increase patient risks for chronic disease complications. A systematic review of the literature was conducted to understand LGBT cultural competencies for nursing and other health care providers. The Cochrane Handbook for Systematic Reviews and Melnyk\u27s levels of evidence framed this systematic literature review. Articles for inclusion were limited to those published in English between 2008 and 2018. Keywords used in the literature search included LGBT health disparity, LGBT cultural competency orientation, and nursing LGBT education. The search yielded 70 article results, which were further reduced to 12 articles by critically analyzing the applicability of the literature to the practice-related questions and removing duplicate articles. Five articles met the criteria for Levels III-IV (case-control or cohort), 6 met the criteria for Level II (randomized control trials), and 1 was Level 1 (systematic review). The analysis of evidence demonstrated the importance of providing education to nurses and other health care providers regarding LGBT cultural competency. Recommendations are offered for best practice strategies regarding the inclusion of LGBT cultural competencies in nursing orientation modules. Application of the findings may lead to positive social change if knowledgeable health care providers engage the LGBT population in primary care leading to improved health care outcomes
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