7,499 research outputs found

    Multiwavelength pyrometry for nongray surfaces in the presence of interfering radiation

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    A NASA developed multiwavelength pyrometry technique for nongray surfaces was extended to also measure surface temperature in the presence of interfering radiation. This radiation is produced by heat lamps used to raise the temperature of the surface. The necessary instruments are a spectral radiometer, an auxiliary radiation source, and a computer. Four radiation spectra are recorded: (1) the unobstructed spectrum characterizing an auxiliary radiation source; (2) the unobstructed spectrum characterizing the interfering radiation; (3) the radiation spectrum consisting of surface emission plus the interfering radiation; and (4) a spectrum consisting of the radiations of (3) plus the reflected radiation due to the incidence of the auxiliary radiation source on this surface. With these spectra, application of two variable, nonlinear, least squares, curve fitting computer software determines the surface temperature and the spectral emissivity. Use of the method to measure the surface temperature of silicon carbide under a simulated interference condition is shown at a low temperature just above ambient. The instrumentation necessary to extend the method to elevated temperatures is discussed

    Changes in earth's energy flows and clouds in 228-year simulation with a high resolution AGCM

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    Preliminary investigation on auto-thermal extrusion of ground tire rubber

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    Ground tire rubber (GTR) was processed using an auto-thermal extrusion as prerequisite to green reclaiming of GTR. The reclaimed GTR underwent a series of tests: thermogravimetric analysis combined with Fourier-transform infrared spectroscopy (TGA-FTIR), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and static headspace and gas chromatography-mass spectrometry (SHS-GC-MS) in order to evaluate the impact of barrel heating solution (with/without external barrel heating) on reclaiming process of GTR. Moreover, samples were cured to assess the impact of reclaiming heating solution on curing characteristics and physico-mechanical properties. Detailed analysis of the results indicated that the heat supplied by the machinery was replaced by energy generated due to the high shearing phenomenon, what significantly influenced energy consumption and hereby lowered processing costPostprint (published version

    Survey of finance companies, 2000

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    Against a backdrop of robust economic activity, the finance company sector expanded briskly over the second half of the 1990s. The value of receivables held by finance companies in the United States rose nearly 50 percent, or about 11 percent a year, between 1996 and 2000. Business lending remained finance companies' major line of activity; the importance to the sector of consumer lending and leasing declined slightly, and the importance of real estate lending rose a bit. These and other findings from the Federal Reserve's mid-2000 benchmark survey of finance companies, as well as developments in the sector since that time, are discussed in this article.Finance companies

    Analysis of Commodity Program Adjustments for U.S. Rice in Stochastic Framework

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    Potential adjustments in U.S. commodity program for rice are evaluated in this paper using stochastic analysis in a global modeling framework. Corresponding threshold and loss-compensatory increases in target price and loan rates are determined with assumed outright and gradual elimination of direct payments. Results show that if direct payments (DP) are eliminated in 2012, a 23% increase in both the target price (TP) and loan rate (LR) triggers counter-cyclical payments (CCP) 80% of the time; and it will take an increase of 48% in TP and LR to generate CCP enough to compensate for the loss in total DP. If DP is gradually removed over 5 years, the trigger and compensatory increases in TP and LR are 41% and 46%, respectively. Furthermore, if DP is eliminated outright and TP maintained, an increase of 71% in LR triggers loan deficiency payments (LDP) 75% of the time; and it will take an increase of 130% in LR to generate enough LDP to recoup the total loss in DP. Under gradual removal of DP, the trigger and compensatory increases in LR are 71% and 92%, respectively.U.S. commodity program, threshold and loss-compensatory increases, stochastic analysis, Agricultural and Food Policy, Crop Production/Industries, Q18,

    40 Gbps Access for Metro networks: Implications in terms of Sustainability and Innovation from an LCA Perspective

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    In this work, the implications of new technologies, more specifically the new optical FTTH technologies, are studied both from the functional and non-functional perspectives. In particular, some direct impacts are listed in the form of abandoning non-functional technologies, such as micro-registration, which would be implicitly required for having a functioning operation before arrival the new high-bandwidth access technologies. It is shown that such abandonment of non-functional best practices, which are mainly at the management level of ICT, immediately results in additional consumption and environmental footprint, and also there is a chance that some other new innovations might be 'missed.' Therefore, unconstrained deployment of these access technologies is not aligned with a possible sustainable ICT picture, except if they are regulated. An approach to pricing the best practices, including both functional and non-functional technologies, is proposed in order to develop a regulation and policy framework for a sustainable broadband access.Comment: 10 pages, 6 Tables, 1 Figure. Accepted to be presented at the ICT4S'15 Conferenc

    A catalog of atmospheric densities from the drag on five artificial satellites

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    Atmospheric densities from satellite drag dat

    Ground state and excitation dynamics in Ag doped helium clusters

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    We present a quantum Monte Carlo study of the structure and energetics of silver doped helium clusters AgHen_n for nn up to 100. Our simulations show the first solvation shell of the Ag atom to be composed by roughly 20 He atoms, and to possess a structured angular distribution. Moreover, the electronic 2^2P1/22_{1/2}\leftarrow ^2S1/2_{1/2} and 2^2P3/22_{3/2}\leftarrow ^2S1/2_{1/2} electronic transitions of the embedded silver impurity have been studied as a function of the number ofhelium atoms. The computed spectra show a redshift for n15n\leq 15 and an increasing blueshift for larger clusters, a feature attributed to the effect of the second solvation shell of He atoms. For the largest cluster, the computed excitation spectrum is found in excellent agreement with the ones recorded in superfluid He clusters and bulk. No signature of the direct formation of proposed AgHe2_2 exciplex is present in the computed spectra of AgHe100_{100}.Comment: 4 Pages, 3 Figures, submitted to Phys. Rev. Let

    Climate change and climate uncertainty in the Murray-Darling Basin

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    Human activity has modified the environment at all scales from the smallest ecosystems to the global climate systems. In the analysis of the Murray-Darling Basin, it is necessary to take account of effects of human activity ranging from local changes in water tables and soil structure through basin-level effects of the expansion of irrigation to changes in precipitation pattern arising from the accumulation of greenhouse gases in the atmosphere. In this paper, we analyse the impact of, and adjustments to, climate change in the Murray-Darling Basin, using a simulation model that incorporates a state-contingent representation of uncertainty.Environmental Economics and Policy,
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