92 research outputs found
THE STRUGGLE FOR BROADBAND IN RURAL AMERICA
Broadband, Digital Divide, Economic Development, Infrastructure, Rural Development, Community/Rural/Urban Development, Research and Development/Tech Change/Emerging Technologies, L96, R11, R58,
Experimental study of the effects of Reynolds number on high angle of attack aerodynamic characteristics of forebodies during rotary motion
The National Aeronautics and Space Administration and the Defense Research Agency (United Kingdom) have ongoing experimental research programs in rotary-flow aerodynamics. A cooperative effort between the two agencies is currently underway to collect an extensive database for the development of high angle of attack computational methods to predict the effects of Reynolds number on the forebody flowfield at dynamic conditions, as well as to study the use of low Reynolds number data for the evaluation of high Reynolds number characteristics. Rotary balance experiments, including force and moment and surface pressure measurements, were conducted on circular and rectangular aftbodies with hemispherical and ogive noses at the Bedford and Farnborough wind tunnel facilities in the United Kingdom. The bodies were tested at 60 and 90 deg angle of attack for a wide range of Reynolds numbers in order to observe the effects of laminar, transitional, and turbulent flow separation on the forebody characteristics when rolling about the velocity vector
Effects of the Working Fluid Charge in Organic Rankine Cycle Power Systems: Numerical and Experimental Analyses
It is well known that organic Rankine cycle (ORC) power systems often operate in conditions differing from the nominal design point due to variations of the heat source and heat sink conditions. Similar to a vapor compression cycle, the system operation (e.g., subcooling level, pump cavitation) and performance (e.g., heat exchanger effectiveness) of an ORC are affected by the working fluid charge. This chapter presents a discussion of the effects of the charge inventory in ORC systems. In particular, both numerical and experimental aspects are presented. The importance of properly predicting the total amount of working fluid charge for optimizing design and off-design conditions is highlighted. Furthermore, an overview on state-of-the-art modeling approaches is also presented
Agritourism around the globe: Definitions, authenticity, and potential controversy
This commentary identifies the variability in definitions of agritourism that exists in a variety of different countries, discusses reasons why this variability might produce problems, and provides examples of efforts to harmonize these definitions, including an ongoing international dialogue on the topic
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A Multilevel Measurement Model of Social Cohesion
In spite of its currency both in academic research and political rhetoric, there are numerous attempts to define and conceptualize the social cohesion concept but there has been paid little attention to provide a rigorous and empirically tested definition. There are even fewer studies that address social cohesion in a framework of cross-cultural validation of the indicators testing the equivalence of the factorial structure across countries. Finally, as far as we know there is no study that attempt to provide an empirically tested multilevel definition of social cohesion specifying a Multilevel Structural Equation Model. This study aims to cover this gap. First, we provide a theoretical construct of social cohesion taking into account not only its multidimensionality but also its multilevel structure. In the second step, to test the validity of this theoretical construct, we perform a multilevel confirmatory factor analysis in order to verify if the conceptual structure suggested in first step holds. In addition, we test the cross-level structural equivalence and the measurement invariance of the model in order to verify if the same multilevel model of social cohesion holds across the 29 countries analysed. In the final step, we specify a second-order multilevel CFA model in order to identify the existence of a general factor that can be called “social cohesion” operating in society that accounts for the surface phenomena that we observe
Time and dosage effects of meprobamate on visual detection
Sixteen male subjects, 21 years and older, were run in a doubleblind own-control design under three dosages of meprobamate (400, 800 and 1600 mg) and matching placebo, to determine response curves on a visual detection task over a four and one-half hour period, from 5:00 to 9:30 p.m. To control for possible daily cycle effects two additional runs under placebo and 1600 mg meprobamate were conducted from 8:00 a.m. to 12:30 p.m.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46406/1/213_2004_Article_BF00710913.pd
Missing the Unhealthy? Examining Empirical Validity of Material Deprivation Indices (MDIs) Using a Partial Criterion Variable
This study investigates the empirical validity of the material deprivation indices (MDIs) using a partial criterion variable, namely UHCNIR (unmet health care need due to inadequate resources). This alternative approach helps to assess absolute validity (Type I and II errors) and sources of error in the measurement of poverty for a specific aspect of poverty (in this case inability to receive adequate health care due to affordability problems). A simple mismatch analysis identifies a sizable group, around 1% of the adult EU population, missed by MDIs despite being in UHCNIR. A majority of this 1% experiences not only UHCNIR but also multiple other deprivations, commonly reports having some difficulties making ends meet, and prevalently has a disability or a chronic health problem. The analysis reveals that MDIs miss specifically those "unhealthy poor" since these measures do not include a relevant item, and thus cannot adjust for different needs and costs in health care and account for the distinct poverty experiences of these people. Therefore, the main methodological assumption of MDIs, identifying the people in poverty with only a limited set of key deprivation indicators is not supported by this empirical analysis
Towards an EU measure of child deprivation
This paper proposes a new measure of child material and social deprivation (MSD) in the European Union (EU) which includes age appropriate child-specific information available from the thematic deprivation modules included in the 2009 and 2014 waves of the “EU Statistics on Income and Living Conditions” (EU‑SILC). It summarises the main results of the in-depth analysis of these two datasets, identifies an optimal set of robust children MSD items and recommends a child‑specific MSD indicator for use by EU countries and the European Commission in their regular social monitoring. In doing this, the paper replicates and expands on the methodological framework outlined in Guio, Gordon and Marlier (2012), particularly by including additional advanced reliability tests
The Variation of Refractive Powers in Solutions: The Variation of the Position of Absorption Bands of Solutions, as Shewn by Measurements of Refractive Index and of Optical Rotary Power.
Abstract Not Provided
The Variation of Refractive Powers in Solutions: The Variation of the Position of Absorption Bands of Solutions, as Shewn by Measurements of Refractive Index and of Optical Rotary Power.
Abstract Not Provided
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