219,873 research outputs found
Simple drag prediction strategies for an Autonomous Underwater Vehicle’s hull shape
No full textThe range of an AUV is dictated by its finite energy source and minimising the energy consumption is required to maximise its endurance. One option to extend the endurance is by obtaining the optimum hydrodynamic hull shape with balancing the trade-off between computational cost and fluid dynamic fidelity. An AUV hull form has been optimised to obtain low resistance hull. Hydrodynamic optimisation of hull form has been carried out by employing five parametric geometry models with a streamlined constraint. Three Genetic Algorithm optimisation procedures are applied by three simple drag predictions which are based on the potential flow method. The results highlight the effectiveness of considering the proposed hull shape optimisation procedure for the early stage of AUV hull desig
An hierarchical approach to hull form design
No full textAs ship design tools become more integrated and more advanced analysis tools are introduced, the ability to rapidly develop and modify hull forms becomes essential. Modern hull design applications give an experienced user the ability to create almost any shape of hull. However, the direct manipulation of hull surface representations is laborious and may limit the exploration of design concept to the fullest extent. Transformation of parent forms and parametric hull generation tools can provide a quick solution, but neither method is conducive for innovative design. A hull design tool is required that can integrate the separate techniques creating a fair hull form surface that can be modified easily throughout the design process. This paper explores the concept of separating the hull surface into global and local features by establishing a hierarchical definition structure and introduces some of the benefits of this approach
Political correspondence relating to Kingston-upon-Hull, 1678-1835
No full textThis study covers aspects of political life at Kingston-upon-Hull between 1678 and 1835, and is part history and part edition. The historical section is an essay on the character and course of Hull politics between these dates. The edition on which that essay is based, consists of a selection from the surviving correspondence. The resulting picture is fragmentary, but it does contribute to our understanding of Hull at that time.
The years 1678 to 1835 were marked by a political stability
at Hull established during the first ten years and challenged only during the concluding five. Until the mid 1830's local political power was held by a merchant-maritime oligarchy which in times of need called upon local magnates who served the town as High Stewards.
The Crown had some influence at Hull, as it was a garrison
town and port; but the town corporation, Trinity House, Dock Company, and a number of wealthy families, some of whom had reached gentry status, held the monopoly of political influence. The freeman electorate was large, and as elections approached, unregistered voters pressed
the Bench for their franchise. Some attempt was made by the corporation to restrict this. The paying of polling money was almost inevitable, especially in the later eighteenth century, and wise candidates also contributed to local charities, clubs and racing plates.
Members of Parliament kept the town fully informed of national political issues especially up to about 1710. From then until the late 1760's the members seem less assiduous in their correspondence, and also in their performance in the Commons. Between 1766 and 1820 the Rockingham Fitzwilliam interest returned many personal nominees, and the quality of many of the members rose. These Whig magnates did not, however, have a monopoly at Hull. Wilberforce stood as an independent and later several government, or perhaps Tory candidates, were returned. Closely contested and expensive elections were common after 1796.
Threats from Jacobites and American privateers, with the possibility of a French invasion, caused local political squabbles, but the French danger may have helped prevent the spread of revolutionary societies and Radicalism was really born in Hull in 1818 with the Political Protestants. However it played some part in turning Hull Whig/Liberal opinion against Liverpool's Tory government.
The 1830's, with the campaign for the Reform and Municipal
Corporation Acts, led to a crystallisation of local political parties which culminated in the defeat of the Tory corporation in the municipal election of 1835. The activities of the radical Acland added to the political strife, but he overplayed his hand. The stability
created by conflict in the 1680's was transformed by conflict in the 1830's. The intervening years thus have some unity
Hull, Robert N. -- 1953-66 -- Correspondence, Individual -- letter, 1956-12-26
No full textLetter from Hull, Robert N. to Alvarez, Ramos M. dated 1956-12-26.Sabin Collection Fair Use Policy</a
Municipal maternity services Policy and provision 1900-1939 with particular reference to Kingston upon Hull and its municipal maternity home
No full textSIGLEAvailable from British Library Document Supply Centre-DSC:DXN009868 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Flux compactifications of M-theory on twisted tori
No full textWe find the bosonic sector of the gauged supergravities that are obtained from 11-dimensional supergravity by Scherk-Schwarz dimensional reduction with flux to any dimension D. We show that, if certain obstructions are absent, the Scherk-Schwarz ansatz for a finite set of D-dimensional fields can be extended to a full compactification of M-theory, including an infinite tower of Kaluza-Klein fields. The internal space is obtained from a group manifold (which may be non-compact) by a discrete identification. We discuss the symmetry algebra and the symmetry breaking patterns and illustrate these with particular examples. We discuss the action of U-duality on these theories in terms of symmetries of the D-dimensional supergravity, and argue that in general it will take geometric flux compactifications to M-theory on non-geometric backgrounds, such as U-folds with U-duality transition functions
Bayesian surface estimation from multiple cameras using a prior based on the visual hull and its application to image based rendering
No full textThe problem of visible surface estimation for image-based rendering is tackled using a new approach, which combines visual hull and surface estimation techniques. It is shown that the new method combines the best features of both approaches, being more robust than direct surface element estimation and more flexible than the visual hull. The new method uses an estimate of the visual hull as a prior on the ill-posed problem of surface element estimation. To improve the computational preformance of the algorithm, a multiresolution approach to surface patch estimation is used. The patches thus estimated can then be tracked over time, to provide an accurate model of the surface geometry, which is then used for estimation of the scene from arbitrary viewpoints. After a brief description of the algorithm, results are presented to show the improvement in performance which can be obtained using either technique alone. The paper concludes with a discussion of extensions to the work currently under investigation
The lichen flora of Hull, with particular reference to zonal distribution and environmental monitoring
No full textYesThe role of lichens as environmental monitors is widely recognised. Not only are they valuable as indicators of habitat stability and enyironmental continuity, but they are also effectiye in monitoring environmental quality. more particularly air and soil (and more recently water) pollution. In the past. the main role of lichens in this context has been to
monitor sulphur dioxide air pollution. especially stable and rising levels (Seaward 1993).
Howeyer, it has also been shown that lichens arc effective monitors of falling levels of
gaseous sulphur dioxide and indeed of other pollutants. some of which are manifesting
themselves as a consequence of the reduction in the former; of particular interest in this
respect is the use of lichens to detect and determine the extent of qualitative changes in air pollution such as the impact of acid rain and hypertrophication (Seaward 1997: Seaward & Coppins 2(04)
Portrait of Representative Cordell Hull.
No full textHandwritten inscription: \u27To Mr. Felton M. Johnston, with highest esteem Cordell Hull\u27https://egrove.olemiss.edu/fmjohnston/1107/thumbnail.jp
Analysis on the hull girder ultimate strength of a bulk carrier using simplified method based on an incremental-iterative approach
No full textThe hull girder ultimate strength of a typical bulk carrier is analyzed using a simplified method based on an incremental-iterative approach. First, vertical bending moment is examined by seven different methods. The moment versus curvature curves and the values of the ultimate longitudinal moments at collapse states are determined for both hogging and sagging cases. Second, the ultimate strength under coupled vertical and horizontal bending moment is accounted. An interaction curve is obtained, which corresponds to the results of series of calculation for the ship hull subject to bending conditions with different angles of curvature. It is found that the interaction curve is asymmetrical because the hull cross section is not symmetrical with respect to the horizontal axis and the structural response of the elements under compression is different from that under tension due to nonlinearity caused by buckling. The angles of the resultant bending moment vector and that of the curvature vector are different in investigated cases. The interaction design equations proposed by other researches are also addressed to discuss the results presented by this study
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