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51.
The adhesion to glass of rubbers with different relaxation properties but similar surface condition has been compared using the thin film peel test. At higher peeling stresses, the rubber–glass interface fractured at constant velocity and all rubbers gave the same adhesive energy values. However, at lower peel stresses, the lossy rubber appeared to adhere more strongly due to a crack-slowing phenomenon at the rubber–glass interface.  相似文献   
52.
Cost minimization multi-product production problems with static production resource usage and internal product flow requirements have been solved by linear programming (LP) with input/output analysis. If the problem is complicated by interval resource estimates, interval linear programming (ILP) can be used. The solution of realistic problems by the above method is cumbersome. This paper suggests that linear goal programming (LGP) can be used to model a multi-product production system. LGP's unique modeling capabilities are used to solve a production planning problem with variable resource parameters. Input/output analysis is used to determine the technological coefficients for the goal constraints and is also used to derive an information sub-model that is used to reduce the number of variable resource goal constraints. Preliminary findings suggest that the LGP approach is more cost-efficient (in terms of CPU time) and in addition provides valuable information for aggregate planning.  相似文献   
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Cross sections for inclusive inelastic electron scattering from H, D, Be, Al, Cu and Au have been measured at 6° for incident energies up to 19.5 GeV. Within the stated errors, the cross sections were found to be directly proportional to the sum of the constituent nucleon cross sections.  相似文献   
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Deep-inelastic structure functions W1 and W2 have been extracted from electron-proton scattering cross sections that were measured in recent experiments at SLAC. The structure functions display deviations from scaling in the variable ω in the kinetic range 1.5 ? ω ? 3.0 and 2 ? Q2 ? 15 GeV2.  相似文献   
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Summary Two generalisations of Brownian motion to several-dimensional time are considered and the topology of their level sets is analysed. It is shown that for these maps non-trivial contours are quite rare — their union has Lebesgue measure zero. The boundedness of all contours is established for the generalisation due to Lévy. For the other, the Brownian sheet, a partial result concerning the behaviour of the zero contour near the boundary is established.Most of the results in this paper were obtained in the course of an S.R.C studentship at the University of Oxford, and appear in the ensuing D. Phil. thesis. I wish to acknowledge the encouragement of my supervisor John Kingman, and the stimulus of correspondence with J.B. Walsh and R. Pyke.  相似文献   
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This paper presents a real-world, capacitated examination timetabling problem from Universiti Malaysia Pahang (UMP), Malaysia. The problem has constraints which have not been modelled before, these being the distance between examination rooms and splitting exams across several rooms. These constraints provide additional challenges in defining a suitable model and in developing a constructive heuristic. One of the contributions of this paper is to formally define this real-world problem. A further contribution is the constructive heuristic that is able to produce good quality solutions for the problem, which are superior to the solutions that are produced using the university’s current software. Moreover, our method adheres to all hard constraints which the current systems fails to do.  相似文献   
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