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101.
Martin Charles Golumbic 《Graphs and Combinatorics》1988,4(1):307-321
Let be a family of sets. The intersection graph of is obtained by representing each set in by a vertex and connecting two vertices by an edge if and only if their corresponding sets intersect. Of primary interest are those classes of intersection graphs of families of sets having some specific topological or other structure. The grandfather of all intersection graphs is the class of interval graphs, that is, the intersection graphs of intervals on a line.The scope of research that has been going on in this general area extends from the mathematical and algorithmic properties of intersection graphs, to their generalizations and graph parameters motivated by them. In addition, many real-world applications involve the solution of problems on such graphs.In this paper a number of topics in algorithmic combinatorics which involve intersection graphs and their representative families of sets are presented. Recent applications to computer science are also discussed. The intention of this presentation is to provide an understanding of the main research directions which have been investigated and to suggest possible new directions of research. 相似文献
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Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Elliott JR Escobar CO Estabrooks P Gibney MC Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Nauenberg U Ong P Pinfold J Punkar G Purohit MV Raab JR Santoro AF Sidhu JS Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundia AB Witherell MS 《Physical review letters》1988,60(14):1379-1381
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R. Kleiss A. D. Martin W. J. Stirling 《Zeitschrift fur Physik C Particles and Fields》1988,39(3):393-398
We study means of identifying top quarks of mass in the range 70–120 GeV at the CERN and FNAL \(\bar pp\) colliders. We show that “W+dijet” production presents a serious background to the conventional “isolated electron+dijet” signature of top. We study an improved signature, calculate the expected event rates, and discuss the determination of the mass of the top quark. 相似文献
107.
S. W. Martin 《Applied Physics A: Materials Science & Processing》1989,49(3):239-247
That ionic conductivity in glass is a non-exponential process and has been known for many years. The amorphous structure of glass and hence a distribution of cation sites has often been thought to be the cause for the non-exponentiality. Almost completely unresearched, however, has been the effect of glass composition on the nature of the relaxation process. In this paper, we review the observations that have been made of the relationships between glass composition and the non-exponential character of the conductivity relaxation as well combine our recent wide composition range studies of sodium aluminoborate and lithium phosphate glasses to delineate the major features of the correlation. By examining glass compositions ranging from 0.02 to 60 mole% alkalioxide, it is observed that the rapid development of non-exponentiality within 1% Na2O is accompanied by a similar rapid decrease in the average cation-cation separation distance, this being calculated using the composition and density. Other quantities such as the dc conductivity or activation energy are observed to vary too slowly with composition to produce a linear correlation with the extent of non-exponentiality as monitored in the parameter of the stretched exponentialkww function. 相似文献
108.
An optical fiber-chromatographic sensor, aiming at simultaneous and selective response to multiple components following a chromatographic separation, is described. We report an improved approach for immobilization of octadecyl (C(18)) and methyl (C(1)) moieties as stationary phase on an optical fiber suitable as a sensing phase for organic solutes. By this approach, the stability and lifetime of the sensing layer as well as the detectability and retention behavior of the chromatographic sensor could be improved. Infrared spectroscopy was employed to confirm the presence of C(18) and C(1) moieties on the modified surface of the optical fiber. The chromatographic sensor was applied, with good sensitivity and chemical selectivity, to the simultaneous separation and detection of bromobenzene and toluene, using water as the mobile phase. 相似文献
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