34,771 research outputs found

    Energy storage using high pressure electrolysis and methods for reconversion

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    Theoretical and experimental studies on high pressure electrolysis producing hydrogen and oxygen for energy storage and reconversion are reported. Moderate temperature, high pressure hydrogen/oxygen fuel cells with nickel electrodes are investigated for effects of pressure, temperature, and membrane porosity. Test results from an aphodid burner turbine generator combination obtained 40 percent kilowatt hours out of the fuel cell divided by kilowatt hours into the electrolyzer. It is concluded that high pressure hydrogenation of organic materials can be used to synthesize hydrozenes and methanes for making synthetic vehicular fuels

    The Occupational Structure of Further and Higher Education in Ireland and the Netherlands

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    Although most types of education give access to a range of occupations, the educational background determines to a large extent the labour market possibilities of a worker. However, since educational systems vary widely between different countries, there is a question about the specific role of each type of education in a country and the influence of the structure of the educational system as a whole on the relationship between education and the labour market. In this paper a comparison of the occupational structure of further and higher education in Ireland and the Netherlands is made. This comparison is based on a common occupational classification, which provides the possibility of measuring the extent of the occupational domains of types of education and the overlap in occupational domain of different types of education within each country and between both countries. The extent of the occupational domain and the similarities within a country provide information about aspects of the occupational structure of higher education in both countries, while the similarities between types of education in both countries make it possible to determine in a simple way the mutual position of types of education in the two countries. It is shown in the paper that since the Irish education system is more generally oriented than the Dutch system, Ireland has a broader occupational domain for similar types of further and higher education, on average, than the Netherlands. In addition the occupational domains for academics and technicians in Ireland have more overlap between different fields of study than in the Netherlands. Furthermore, despite the fact that the fraction of higher educated people in the Netherlands considerably exceeds the fraction in Ireland – which might result in some qualifications inflation – some types of education in Ireland, such as engineering and agricultural science, at higher levels seem to be closer to the Dutch intermediate vocational level than to the higher level.education, training and the labour market;

    Recent integral cross section validation measurements at the ASP facility

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    This work presents new integral data measured at the ASP 14 MeV neutron irradiation facility at Aldermaston in the UK, which has recently become available for fusion-related work through the CCFE materials programme. Measurements of reaction products from activation experiments using elemental foils were carried out using gamma spectrometry in a high efficiency, high-purity germanium (HPGe) detector and associated digital signal processing hardware. Following irradiation and rapid extraction to the measurement cell, gamma emissions were acquired with both energy and time bins. Integral cross section and half-life data have been derived from these measurements. Selected integral cross section values are presented from the measurement campaigns.Comment: 4 pages, 5 figure

    Implementing fully relativistic hydrodynamics in three dimensions

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    We report on our numerical implementation of fully relativistic hydrodynamics coupled to Einstein's field equations in three spatial dimensions. We briefly review several steps in our code development, including our recasting of Einstein's equations and several tests which demonstrate its advantages for numerical integrations. We outline our implementation of relativistic hydrodynamics, and present numerical results for the evolution of both stable and unstable Oppenheimer-Volkov equilibrium stars, which represent a very promising first test of our code.Comment: 5 Pages, 4 Figures, submitted to Proceedings of the 8th Canadian Conference on General Relativity and Relativistic Astrophysic

    Exercise-induced tendon and bone injury in recreational runners: A test-retest reliability study

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    Background: Long-distance runners are prone to injuries including Achilles tendinopathy and medial tibial stress syndrome. We have developed an Internet comprehensive self-report questionnaire examining the medical history, injury history, and running habits of adult recreational runners. Objective: The objective of the study was to evaluate two alternative forms of test-retest reliability of a comprehensive self-report Internet questionnaire retrospectively examining the medical history, injury history, and running habits among a sample of adult recreational runners. This will contribute to the broad aims of a wider study investigating genetics and running injury. Methods: Invitations to complete an Internet questionnaire were sent by email to a convenience pilot population (test group 1). Inclusion criteria required participants to be a recreational runner age 18 or over, who ran over 15 km per week on a consistent basis. The survey questions addressed regular running habits and any injuries (including signs, symptoms, and diagnosis) of the lower limbs that resulted in discontinuation of running for a period of 2 consecutive weeks or more, within the last 2 years. Questions also addressed general health, age, sex, height, weight, and ethnic background. Participants were then asked to repeat the survey using the Internet platform again after 10-14 days. Following analysis of test group 1, we soft-launched the survey to a larger population (test group 2), through a local running club of 900 members via email platform. The same inclusion criteria applied, however, participants were asked to complete a repeat of the survey by telephone interview after 7-10 days. Selected key questions, important to clarify inclusion or exclusion from the wider genetics study, were selected to evaluate test-retest reliability. Reliability was quantified using the kappa coefficient for categorical data. Results: In response to the invitation, 28 participants accessed the survey from test group 1, 23 completed the Internet survey on the first occasion, and 20 completed the Internet retest within 10-21 days. Test-retest reliability scored moderate to almost perfect (kappa=.41 to .99) for 19/19 of the key questions analyzed. Following the invitation, 122 participants accessed the survey from test group 2, 101 completed the Internet survey on the first occasion, and 50 were randomly selected and contacted by email inviting them to repeat the survey by telephone interview. There were 33 participants that consented to the telephone interview and 30 completed the questionnaire within 7-10 days. Test-retest reliability scored moderate to almost perfect for 18/19 (kappa=.41 to .99) and slight for 1/19 of the key questions analyzed. Conclusions: We successfully developed a self-reported, retrospective questionnaire, delivered using Internet software, providing stable and reliable answers. We demonstrate that our survey provides a relatively quick, easy to complete, and cost effective method to collect epidemiological data from recreational runners and evaluate these participants for inclusion into a genetic study

    It's Not Just the ATMs: Technology, Firm Strategies, Jobs, and Earnings in Retail Banking

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    The authors examine trends in job content and earnings in selected jobs in two American banks. Firm restructuring and technological changes resulted in higher earnings for college-educated workers. The banks followed different strategies in implementing these changes for lower-skill jobs, with different effects on bank tellers in particular. The authors conclude that technology enables workplace reform but does not determine its effect on jobs and earnings; these effects are contingent on managerial strategies. This focus on organizational processes and managerial strategy provides a complementary approach to accounts of growing inequality that center solely on the role of individual skills and technological change.

    Modeling radiation belt radial diffusion in ULF wave fields: 1. Quantifying ULF wave power at geosynchronous orbit in observations and in global MHD model

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    [1] To provide critical ULF wave field information for radial diffusion studies in the radiation belts, we quantify ULF wave power (f = 0.5–8.3 mHz) in GOES observations and magnetic field predictions from a global magnetospheric model. A statistical study of 9 years of GOES data reveals the wave local time distribution and power at geosynchronous orbit in field-aligned coordinates as functions of wave frequency, solar wind conditions (Vx, ΔPd and IMF Bz) and geomagnetic activity levels (Kp, Dst and AE). ULF wave power grows monotonically with increasing solar wind Vx, dynamic pressure variations ΔPd and geomagnetic indices in a highly correlated way. During intervals of northward and southward IMF Bz, wave activity concentrates on the dayside and nightside sectors, respectively, due to different wave generation mechanisms in primarily open and closed magnetospheric configurations. Since global magnetospheric models have recently been used to trace particles in radiation belt studies, it is important to quantify the wave predictions of these models at frequencies relevant to electron dynamics (mHz range). Using 27 days of real interplanetary conditions as model inputs, we examine the ULF wave predictions modeled by the Lyon-Fedder-Mobarry magnetohydrodynamic code. The LFM code does well at reproducing, in a statistical sense, the ULF waves observed by GOES. This suggests that the LFM code is capable of modeling variability in the magnetosphere on ULF time scales during typical conditions. The code provides a long-missing wave field model needed to quantify the interaction of radiation belt electrons with realistic, global ULF waves throughout the inner magnetosphere

    Experimental Predictions of The Functional Response of A Freshwater Fish

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    The functional response is the relationship between the feeding rate of an animal and its food density. It is reliant on two basic parameters; the volume searched for prey per unit time (searching rate) and the time taken to consume each prey item (handling time). As fish functional responses can be difficult to determine directly, it may be more feasible to measure their underlying behavioural parameters in controlled conditions and use these to predict the functional response. Here, we tested how accurately a Type II functional response model predicted the observed functional response of roach Rutilus rutilus, a visually foraging fish, and compared it with Type I functional response. Foraging experiments were performed by exposing fish in tank aquaria to a range of food densities, with their response captured using a two-camera videography system. This system was validated and was able to accurately measure fish behaviour in the aquaria, and enabled estimates of fish reaction distance, swimming speed (from which searching rate was calculated) and handling time to be measured. The parameterised Type II functional response model accurately predicted the observed functional response and was superior to the Type I model. These outputs suggest it will be possible to accurately measure behavioural parameters in other animal species and use these to predict the functional response in situations where it cannot be observed directly
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