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91.
Digraph games are cooperative TU-games associated to digraph competitions: domination structures that can be modeled by directed
graphs. Examples come from sports competitions or from simple majority win digraphs corresponding to preference profiles for
a group of individuals within the framework of social choice theory. Brink and Gilles (2000) defined theβ-measure of a digraph competition as the Shapley value of the corresponding digraph game. This paper provides a new characterization
of theβ-measure. 相似文献
92.
93.
Georg Stamou 《Journal of Geometry》1993,47(1-2):155-162
In this paper we study certain associated ruled surfaces of a nonparabolic rectilinear congruenceS in the simply isotropic space. We give two characterizations of the curvature ofS via minimal properties and a new characterization of the pseudospherical congruences of this space.
Herrn Prof. Dr. O. Giering zum 60. Geburtstag gewidmet 相似文献
Herrn Prof. Dr. O. Giering zum 60. Geburtstag gewidmet 相似文献
94.
95.
96.
Hans Peters Hans van der Stel Ton Storcken 《Mathematical Methods of Operations Research》1993,38(2):213-229
A voting scheme assigns to each profile of alternatives reported byn individuals a compromise alternative. A voting scheme is strategy-proof if no individual is better off by lying, i.e., not reporting a best alternative. In this paper the main results concern the case where the set of alternatives is the Euclidean plane and the preferences are Euclidean. It is shown that for strategy-proof voting schemes continuity is equivalent to convexity of the range of the voting scheme. Using a result by Kim and Roush (1984), this leads to characterizations of surjective or unanimous, anonymous, strategy-proof voting schemes.Furthermore, the paper contains an extensive discussion of related results in the area. 相似文献
97.
We present a new algorithm for the identification of ring pairs in Cherenkov detectors. The approach combines linear regression methods for the construction of an appropriate reference quantity, methods from statistics for the evaluation of hypotheses and Monte Carlo simulation runs for the tuning of threshold levels. 相似文献
98.
Patterson JR Barker A Briere RA Gibbons LK Makoff G Papadimitriou V Somalwar S Wah YW Winstein B Winston R Woods M Yamamoto H Swallow E Bock GJ Coleman R Enagonio J Hsiung YB Stanfield K Stefanski R Yamanaka T Blair G Gollin GD Karlsson M Okamitsu JK Tschirhart R Brisson JC Debu P Peyaud B Turlay R Vallage B 《Physical review letters》1990,64(13):1491-1494
99.
Preservation mechanisms of trehalose in food and biosystems 总被引:15,自引:0,他引:15
The stability or shelf-life of food and biomaterials has always been a critical issue in the food and pharmaceutical industry. Trehalose (alpha-D-glucopyranosyl-alpha-D-glucopyranoside), a non-reducing diglucose sugar found in nature, confers to certain plant and animal cells the ability to survive dehydration for decades and to restore activity soon after rehydration. The interaction between trehalose and cell membranes or proteins, however, remains a debated subject, and a significant amount of work has been done to elucidate the mechanisms resulting in this unique behavior of preservation. This study shows how an interfacial phenomena approach has led to the use of trehalose as an excipient during freeze drying of a variety of products in the pharmaceutical industry. It also suggests opportunities as an ingredient for dried and processed food, as well as a non-toxic cryoprotectant of vaccines and organs for surgical transplants. 相似文献
100.
Werner Georg Nowak 《Monatshefte für Mathematik》1988,106(1):57-63
Assuming the Riemann Hypothesis to be true, an asymptotic with a sharp error term is established for the number of primitive lattice points inside a rational ellipseau
2+buv+cv
2x (a, b, c integers,b
2–4ac<0). A generalization of the result is given applying (as an example) to counting functions of Pythagorean triangles. 相似文献