14,517 research outputs found

    Quantitative evaluation of multiband photographic techniques Final report

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    Quantitative evaluation of multiband photographic techniques using combination of black and white and color photo

    Arkansas Cotton Variety Test 1999

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    The primary aim of the Arkansas Cotton Variety Test is to provide unbiased data regarding the agronomic performance of cotton varieties in the major cotton growing areas in Arkansas. This information helps seed dealers establish marketing strategies and assists producers in choosing varieties to plant. In this way the annual test facilitates the inclusion of new, improved genetic material into Arkansas cotton production. The 1999 test had 67 entries (including 25 transgenic genotypes and 35 first-year entries), which were evaluated at sixsites in eastern Arkansas. The presence of four transgenic and five first-year entries among the top 10 yielding entries suggests that improvement is being accomplished in varietal development. This report also includes the Mississippi County Variety Test (an on-farm evaluation of selected varieties) and on-farm variety trials conducted by the Cooperative Extension Service

    Optical image of a cometary nucleus: 1980 flyby of Comet Encke

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    The feasibility was investigated of obtaining optical images of a cometary nucleus via a flyby of Comet Encke. A physical model of the dust cloud surrounding the nucleus was developed by using available physical data and theoretical knowledge of cometary physics. Using this model and a Mie scattering code, calculations were made of the absolute surface brightness of the dust in the line of sight of the on-board camera and the relative surface brightness of the dust compared to the nucleus. The brightness was calculated as a function of heliocentric distance and for different phase angles (sun-comet-spacecraft angle)

    The EU Water Initiative at 15: Origins, Processes and Assessment

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    This article examines the activities and achievements of the European Union Water Initiative, a transnational, multi-actor partnership established in 2002 by the European Commission to support water governance reforms around the world. Two regional components of the initiative – (a) Africa and (b) Eastern Europe, Caucasus and Central Asia – are studied with a focus on their organizational structures, activities, policies and achievements. The analysis provides evidence for improved regional dialogue and cooperation in the water sector, but also points to persistent weaknesses, in particular a lack of resources, ownership and mutual understanding as to the overall aims of the Initiative

    Driver Accelerator Design for the 10 kW Upgrade of the Jefferson Lab IR FEL

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    An upgrade of the Jefferson Lab IR FEL is now under construction. It will provide 10 kW output light power in a wavelength range of 2-10 microns. The FEL will be driven by a modest-sized 80-210 MeV, 10 mA energy-recovering superconducting RF (SRF) linac. Stringent phase space requirements at the wiggler, low beam energy, and high beam current subject the design to numerous constraints. These are imposed by the need for both transverse and longitudinal phase space management, the potential impact of collective phenomena (space charge, wakefields, beam break-up (BBU), and coherent synchrotron radiation (CSR)), and interactions between the FEL and the accelerator RF system. This report addresses these issues and presents an accelerator design solution meeting the requirements imposed by physical phenomena and operational necessities.Comment: submission THC03 for LINAC200

    Regional agriculture surveys using ERTS-1 data

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    The Center for Remote Sensing Research has conducted studies designed to evaluate the potential application of ERTS data in performing agricultural inventories, and to develop efficient methods of data handling and analysis useful in the operational context for performing large area surveys. This work has resulted in the development of an integrated system utilizing both human and computer analysis of ground, aerial, and space imagery, which has been shown to be very efficient for regional crop acreage inventories. The technique involves: (1) the delineation of ERTS images into relatively homogeneous strata by human interpreters, (2) the point-by-point classification of the area within each strata on the basis of crop type using a human/machine interactive digital image processing system; and (3) a multistage sampling procedure for the collection of supporting aerial and ground data used in the adjustment and verification of the classification results

    Living and working in space. A history of Skylab

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    The history of Skylab is examined with emphasis on program development from previous Apollo missions, modifications to spacecraft, onboard experiments, and flight crew training. A listing of the missions and an evaluation of results are included with a brief description of the workshop's reentry

    Kilohertz QPOs in Neutron Star Binaries modeled as Keplerian Oscillations in a Rotating Frame of Reference

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    Since the discovery of kHz quasi-periodic oscillations (QPO) in neutron star binaries, the difference between peak frequencies of two modes in the upper part of the spectrum, i.e. Delta (omega)=omega_h-omega_K has been studied extensively. The idea that the difference Delta(omega) is constant and (as a beat frequency) is related to the rotational frequency of the neutron star has been tested previously. The observed decrease of Delta(omega) when omega_h and omega_k increase has weakened the beat frequency interpretation. We put forward a different paradigm: a Keplerian oscillator under the influence of the Coriolis force. For such an oscillator, omega_h and the assumed Keplerian frequency omega_k hold an upper hybrid frequency relation: omega^2_h-omega^2_K=4*Omega^2, where Omega is the rotational frequency of the star's magnetosphere near the equatorial plane. For three sources (Sco X-1, 4U 1608-52 and 4U 1702-429), we demonstrate that the solid body rotation Omega=Omega_0=const. is a good first order approximation. Within the second order approximation, the slow variation of Omega as a function of omega_K reveals the structure of the magnetospheric differential rotation. For Sco X-1, the QPO have frequencies approximately 45 and 90 Hz which we interpret as the 1st and 2nd harmonics of the lower branch of the Keplerian oscillations for the rotator with vector Omega not aligned with the normal of the disk: omega_L/2 pi=(Omega/pi)(omega_K/omega_h)sin(delta) where delta is the angle between vector Omega and the vector normal to the disk.Comment: 13 pages, 3 figures, accepted for publications in ApJ Letter

    Wipeout? Entrepreneurship, policy interaction and the EU’s 2030 renewable energy target

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    This is the author accepted manuscript. The final version is available from Taylor & Francis (Routledge) via the DOI in this record.In 2014, the European Council set energy and climate targets for 2030 that will have far-reaching implications for the decarbonisation of Europe’s economy as well as the nature and success of the energy integration project, the Energy Union. The targets mark a qualitative shift towards a more technology-neutral EU climate and energy policy than represented in targets for 2020, decided in 2007. Existing explanations emphasise the role of non-state actors but do not fully account for the muted advocacy for a multiple targets approach. This article examines the alternative explanatory power of the concepts of problem surfing and spillover, taken from the multiple streams approach, for interpreting the inability of multiple targets advocates to make a real impact on the policy agenda. Findings suggest that the problematisation of the EU’s ‘flagship’ instrument, the EU-ETS, by policy entrepreneurs and subsequent structural internal alignment of the policy community offer a complementary explanation
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