23,064 research outputs found

    Evaluation of rape-seed oil production, extraction and use as fuel in modified diesel engines

    Get PDF
    End of project reportIt is now well established that rape-seed oil can provide a sustainable source of renewable fuel for diesel engines. The main problem is a high viscosity and vaporisation temperature, which could lead to pumping, atomisation and combustion difficulties. These problems can be overcome in either of two ways: by further processing of the oil to improve its pumping and combustion properties (usually achieved by esterification and layer separation to produce biodiesel) or by some peripheral modifications to the engine to allow it to cope with the more viscous fuel. Engine conversion kits for this purpose are widely available. The second option has attractions in Ireland, at least in the short-term, for a number of reasons. Plants can be established quickly, and so could make an immediate if small contribution to the achievement of Ireland’s substitution target in the Transport Biofuels Directive (Commission of European Communities, 2003). The small operating scale of coldpressing oil extraction plants could be achieved without undue difficulty, and the capital investment required to launch such a project is relatively low. In the event of a biodiesel plant being established at some stage in the future, the option of sourcing some of the oil requirement from these extraction plants would still be available.This study was commissioned by Sustainable Energy Ireland. The complete report has been published on their web-site (www.sei.ie)

    Smart Growth: A Catalyst for Public-Interest Investment

    Get PDF
    Written by a former mayor of Seattle, this Article describes the smart growth movement as a way to sustain the livability of large urban centers in the twenty-first strategy. It describes some of the problems facing urban areas experiencing population growth, namely traffic, rising housing prices and a scarcity of open space. The smart growth movement seeks to address these problems in a cost efficient and environmentally friendly manner. Specifically, it seeks to do so through increased citizen participation in development decisions an constructive dialogue regarding development on individual neighborhoods. Ultimately, the goal of the movement is to make urban areas more attractive to live and work in, creating both investment and jobs. The Article also describes some of the community sacrifices required by the movement, including low-density residential neighborhoods, dependence on the automobile, and the separation of the middle and upper income households from the urban poor

    An air-bearing weight offload system for ground test of heavy LSS structures

    Get PDF
    The capability and use of the Gravity Offload Facility (GOF) are discussed. Briefly explained are the: truss and base casting; carriage assembly; carriage weldment; vertical lift axis control; lifting cylinder; payload gimbal; motion base layout; and control processor

    The PACTUM model: product analysis of cost and time using mathematics

    Get PDF
    Establishing a mathematical supply-chain model is a proposition that has received attention due to its inherent benefits of evolving global supply-chain efficiencies. This paper discusses the prevailing relationships found within apparel supply-chain environments, and contemplates the complex issues indicated for constituting a mathematical model. Principal results identified within the data suggest, that the multifarious nature of global supply-chain activities require a degree of simplification in order to fully dilate the necessary factors which affect, each sub-section of the chain. Subsequently, the research findings allowed the division of supply-chain components into sub-sections, which amassed a coherent method of product development activity. Concurrently, the supply-chain model was found to allow systematic mathematical formulae analysis, of cost and time, within the multiple contexts of each sub-section encountered. The paper indicates the supply-chain model structure, the mathematics, and considers how product analysis of cost and time can improve the comprehension of product lifecycle management

    Magnetic domain formation in itinerant metamagnets

    Get PDF
    We examine the effects of long-range dipolar forces on metamagnetic transitions and generalize the theory of Condon domains to the case of an itinerant electron system undergoing a first-order metamagnetic transition. We demonstrate that within a finite range of the applied field, dipolar interactions induce a spatial modulation of the magnetization in the form of stripes or bubbles. Our findings are consistent with recent observations in the bilayer ruthenate Sr3_3Ru2_2O7_7.Comment: 4 pages, 3 figures, minor changes, references adde

    Plant Populations and Row Widths for Diploid Sugar-beet Varieties.

    Get PDF
    End of Project ReportThe aim of this work was to see whether the introduction of diploid varieties, with their more erect leaf growth, would require any adjustment of the traditional plant spacing and row width recommendations for sugar beet. Five trials were carried out in 1996-98 in which the diploid variety Celt was sown at three row widths: 51, 56 and 61 cm. At each row width, seed spacings were adjusted to give four plant densities between 30,000 and 89,000 plants/ha. In four of the trials, field establishment was between 75 and 90%. In these trials, there was a slight increase in sugar yield with population up to 75,000 plants/ha, and little or no change above this level. There was a slight increase in extractability at higher populations, but not sufficient to have a significant effect on extractable sugar yield. In one trial where plant establishment was reduced by very cold weather, yield and sugar content continued to increase up to the highest plant count of 65,000 plants/ha. Over the five trials, there were no yield or quality differences between 51- and 56-cm rows. There was a reduction of 3.5% in extractable sugar yield in 61-cm rows, though this reached statistical significance in only one trial. Taking into account the high emergence that is normally achieved with diploid varieties, these results suggest that no change should be made to the seed spacings currently recommended for triploid varieties. For those using 61-cm rows, a small yield increase could probably be achieved by reducing row width.Teagasc acknowledges the support of Irish Sugar plc and Sugar Beet Levy Farmer Funds in the financing of this projec

    The Magnetic Topology of the Weak-Lined T Tauri Star V410 - A Simultaneous Temperature and Magnetic Field Inversion

    Full text link
    We present a detailed temperature and magnetic investigation of the T Tauri star V410 Tau by means of a simultaneous Doppler- and Zeeman-Doppler Imaging. Moreover we introduce a new line profile reconstruction method based on a singular value decomposition (SVD) to extract the weak polarized line profiles. One of the key features of the line profile reconstruction is that the SVD line profiles are amenable to radiative transfer modeling within our Zeeman-Doppler Imaging code iMap. The code also utilizes a new iterative regularization scheme which is independent of any additional surface constraints. To provide more stability a vital part of our inversion strategy is the inversion of both Stokes I and Stokes V profiles to simultaneously reconstruct the temperature and magnetic field surface distribution of V410 Tau. A new image-shear analysis is also implemented to allow the search for image and line profile distortions induced by a differential rotation of the star. The magnetic field structure we obtain for V410 Tau shows a good spatial correlation with the surface temperature and is dominated by a strong field within the cool polar spot. The Zeeman-Doppler maps exhibit a large-scale organization of both polarities around the polar cap in the form of a twisted bipolar structure. The magnetic field reaches a value of almost 2 kG within the polar region but smaller fields are also present down to lower latitudes. The pronounced non-axisymmetric field structure and the non-detection of a differential rotation for V410 Tau supports the idea of an underlying α2\alpha^2-type dynamo, which is predicted for weak-lined T Tauri stars.Comment: Accepted for A&A, 18 pages, 10 figure
    • …
    corecore