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101.
Invariants of second-type almost geodesic mappings are obtained in this paper. These invariants are generalizations of Thomas projective parameter and Weyl projective tensor. 相似文献
102.
This paper presents analytical travel time models for the computation of travel time for automated warehouses with the aisle transferring S/R machine (in continuation multi-aisle AS/RS). These models consider the operating characteristics of the storage and retrieval machine such as acceleration and deceleration and the maximum velocity. Assuming uniform distributed storage rack locations and pick aisles and using the probability theory, the expressions of the cumulative distribution functions with which the mean travel time is calculated, have been determined. The computational models enable the calculation of the mean travel time for the single and dual command cycles, from which the performance of multi-aisle AS/RS can be evaluated. A simulation model of multi-aisle AS/RS has been developed to compare the performances of the proposed analytical travel time models. The analyses show that regarding all examined types of multi-aisle AS/RS, the results of proposed analytical travel time models correlate with the results of simulation models of multi-aisle AS/RS. 相似文献
103.
Nenad Miscevic 《Acta Analytica》2013,28(4):509-526
For Rousseau, social contract is a hypothetical one; the paper claims that it is, in contemporary terms, a political thought-experiment (TE). The abductive way of thinking, looking for the best normative pattern in the data, finds its counterpart in the historical abduction in the Second Discourse; the analogy between the two secures the methodological unity of Rousseau’s political philosophy. The proposed reading of the work as a TE shows that it fulfills the necessary requirements put by (hopefully) intuitively acceptable definition of a TE, and fits in the contractarian tradition that has been experimenting with hypothetical arrangements since its start. The reading of The Social Contract as a TE has helped to systematize some of its shortcomings from the wider perspective of methodology of political philosophy. Finally, the political thought experiment (PTE) reading of Rousseau places his central work where it belongs: in the tradition started by Plato’s Republic, continuing with Renaissance and early modern philosophical utopias, culminating in the contractarian social contract TE, and going all the way to the work of Rawls and his present day continuators. We hope that this can contribute to a more positive picture of Rousseau’s work, despite criticism concerning his brusque manner of thought-experimenting. 相似文献
104.
105.
Tomaž Klinc 《Communications in Mathematical Physics》1975,41(3):273-279
It is shown that the set of Case's eigenfunctions of the one speed transport equation is complete in the rigged Hilbert spaceW 2 1 ([?1, 1])?L 2(?1, 1)?W 2 ?1 ([?1, 1]). 相似文献
106.
In the presence of 0.5-1 mol % of FeCl(3) with lithium bromide as a crucial additive, alkynyl Grignard reagents, prepared from the corresponding alkynes and methylmagnesium bromide, react with alkenyl bromides or triflates to give the corresponding conjugated enynes in high to excellent yields. The reaction shows wide applicability to various terminal alkynes and alkenyl electrophiles. 相似文献
107.
Nenad Maraš 《Tetrahedron》2008,64(51):11618-11624
We have evaluated the potential of using tetramethylammonium chloride (Me4NCl) as an alternative methylating agent for phenols under microwave-assisted conditions. Its chemical behavior was tested in a reaction with 2-naphthol in the presence of various bases and solvents. The method was then applied in 1,2-dimethoxyethane or toluene under heterogeneous conditions for the O-methylation of a series of phenolic compounds. We found that many simple phenols can be methylated in the presence of K2CO3, whereas some other less-reactive phenols require the presence of the more reactive Cs2CO3. 相似文献
108.
Nenad Teofanov 《Mediterranean Journal of Mathematics》2016,13(2):745-758
We use sharp convolution estimates for weighted Lebesgue and modulation spaces to obtain an extension of the celebrated Cordero-Gröchenig theorems on boundedness and Schatten–von Neumann properties of localization operators on modulation spaces. We also give a new proof of the Weyl connection based on the kernel theorem for Gelfand–Shilov spaces. 相似文献
109.
110.
Variable neighbourhood search for colour image quantization 总被引:1,自引:0,他引:1
Hansen Pierre; Lazic Jasmina; Mladenovic Nenad 《IMA Journal of Management Mathematics》2007,18(2):207-221
** Email: nenad.mladenovic{at}brunel.ac.uk Colour image quantization is a data compression technique thatreduces the total set of colours in a digital image to a representativesubset. This problem is first expressed as a large M-medianone. The advantages of this model over the usual minimum sum-of-squaresmodel are discussed first and then, the heuristic based on variableneighbourhood search metaheuristic is applied to solve it. Computationalexperience proves that this approach compares favourably withtwo other recent state-of-the-art heuristics, based on geneticand particle swarm searches. 相似文献