Math modeling for helicopter simulation of low speed, low altitude and steeply descending flight

A math model was formulated to represent some of the aerodynamic effects of low speed, low altitude, and steeply descending flight. The formulation is intended to be consistent with the single rotor real time simulation model at NASA Ames Research Center. The effect of low speed, low altitude flight on main rotor downwash was obtained by assuming a uniform plus first harmonic inflow model and then by using wind tunnel data in the form of hub loads to solve for the inflow coefficients. The result was a set of tables for steady and first harmonic inflow coefficients as functions of ground proximity, angle of attack, and airspeed. The aerodynamics associated with steep descending flight in the vortex ring state were modeled by replacing the steady induced downwash derived from momentum theory with an experimentally derived value and by including a thrust fluctuations effect due to vortex shedding. Tables of the induced downwash and the magnitude of the thrust fluctuations were created as functions of angle of attack and airspeed

The transmission of nosocomial pathogens in an intensive care unit: a space–time clustering and structural equation modelling approach

We investigated the incidence of cases of nosocomial pathogens and risk factors in an intensive treatment unit ward to determine if the number of cases is dependent on location of patients and the colonization/infection history of the ward. A clustering approach method was developed to investigate the patterns of spread of cases through time for five microorganisms [methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter spp., Klebsiella spp., Candida spp., and Pseudomonas aeruginosa] using hospital microbiological monitoring data and ward records of patient-bed use. Cases of colonization/infection by MRSA, Candida and Pseudomonas were clustered in beds and through time while cases of Klebsiella and Acinetobacter were not. We used structural equation modelling to analyse interacting risk factors and the potential pathways of transmission in the ward. Prior nurse contact with colonized/infected patients, mediated by the number of patient-bed movements, were important predictors for all cases, except for those of Pseudomonas. General health and invasive surgery were significant predictors of cases of Candida and Klebsiella. We suggest that isolation and bed movement as a strategy to manage MRSA infections is likely to impact upon the incidence of cases of other opportunist pathogen

Minocycline attenuates lipopolysaccharide (LPS)-induced neuroinflammation, sickness behavior, and anhedonia

© 2008 Henry et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Accessing and assessing lunar resources with PROSPECT

PROSPECT is a package in development by ESA to assess the in-situ resource potential of lunar regolith. PROSPECT will: obtain sub-surface regolith samples, extract volatiles, identify chemical species, quantify abundances, and characterize isotopes

EVALUATING THE EFFECTIVENESS OF THE COURSEWARE DEVELOPMENT PROJECT: PILOT STUDIES

This project involves a comprehensive generalizable and transferable evaluation of the Courseware Development Project (CDP) at Dalhousie University\u27s School of Business Administration. This C$3 million, three-year project is divided into four levels over three time phases. The results of the study of the impact of this unique project are expected to be both relevant and applicable to other universities in Canada and throughout the world. This on-going evaluation of the CDP centers around a systems model where: inputs are divided into drivers and materials; throughputs are the conversion processes on a matrix composed of six parties (faculty, students, staff, administrators, organizational structure and processes, and contributing/participating corporations) as the rows and the four levels of the CDP as the columns; and outputs are divided into manifest and latent variables. Demographic, attitudinal, behavioral, and organizational variables will be used in a time series analysis. Using an action research model over the proposed three-year full study, the researchers will assess which elements Of the project are effective at the end of each year of the evaluation. Based on this information the researchers will keep the effective elements in place for the next year and modify any ineffective elements based on the first year\u27s results and competing theory. This cycle will be repeated after year two. Thus the proposed study will contribute to evaluation methodology as described in this paper by treating simultaneously both a case study and a quasiexperiment of the impact of computers on (business) education. A preliminary description of the effects arising from Level 0, the integration of computers in the business school, and Level 1, courseware development. is given here. The general impact of the project upon faculty, staff, and students is described and preliminary findings are presented

Revista de Indias y Anuario de Estudios Americanos. Visibilidad y uso de la edición electrónica

Una década americanista en línea, 2010, [En línea], Puesto en línea el 25 mayo 2010[EN] In this article we analyze the online visibility and content usage of two Americanist Journals published by CSIC, Revista de Indias and Anuario de Estudios Americanos. The online edition dates back to 2007; contents are comparable in terms of accessible documents, and both Journals are published in Open Access, with a 6-months embargo. We also discuss some methodological issues in terms of the need of a data normalization allowing the measurement of genuine downloads assimilable to document reading. Both Journals registered close to 500,000 normalized downloads along 2008 and 2009, most coming from Latin America and the United States (70%). Data show a high degree of repeated downloads of the same document from the same user (25% of total downloads) and indexation downloads (25% of normalized downloads), and also the lack of correlation between Journal’s visibility (webpage visits) and content usage (document downloads). Access restriction has a negative effect, as evidenced by the low downloading of embargoed documents[ES] En este artículo analizamos los datos de visibilidad y uso de las dos revistas de temática americanista editadas por el CSIC, Revista de Indias y Anuario de Estudios Americanos. La edición electrónica de ambas data de 2007, y su contenido en artículos accesibles es comparable; ambas se publican en Acceso Abierto (OA) con un embargo de acceso de 6 meses. También analizamos cuestiones metodológicas relativas al análisis de descargas, en el sentido de la necesidad de una normalización de los datos que permita determinar las descargas reales, asimilables a una lectura del documento. Durante los años 2008 y 2009, ambas revistas han recibido cerca de 500.000 descargas normalizadas, que provienen en su mayoría de Latinoamérica y Estados Unidos (70%). Los datos muestran el elevado número de descargas repetidas de documentos en periodos cortos de tiempo por el mismo usuario (25% de las totales registradas) y de descargas de indización (25% de las descargas normalizadas), y también la falta de correlación entre visibilidad de las revistas (visitas a páginas web) y uso de los contenidos (descarga de documentos). La restricción de acceso tiene un efecto perjudicial, evidenciado por el bajo nivel de descarga de los documentos sometidos a embargoPeer reviewe

Mass Spectrometers for In-Situ Resource Utilisation

The Open University has a heritage in developing small mass spectrometers for planetary lander payloads. The first was a 6 cm radius magnetic sector instrument for light element isotopic analysis (H, C, N, and O), part of the Gas Analysis Package (GAP) on the Beagle 2 Mars lander. The second was the Ptolemy ion trap mass spectrometer (ITMS) on the Philae lander which successfully operated and returned results during the comet landing in November 2014. The Ptolemy ion trap unit fits within a 10 x 10 x 10 cm cube, including RF, detector and ion source electronics and is capable of a mass range from 10 to 150 amu at unit resolution. Development is continuing for purposes ranging from lander instruments (ProSPA and LUVMI), to rugged deployable probes (penetrators) and for process monitoring within ISRU plant. Many of the planned developments are aimed at the various stages of lunar ISRU, from resource prospecting to demonstration and optimisation of extraction processes