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261.
Sebastian Czerwiński 《Information Processing Letters》2008,108(2):64-67
Suppose k runners having different constant speeds run laps on a circular track of unit length. The Lonely Runner Conjecture states that, sooner or later, any given runner is at distance at least 1/k from all the other runners. We prove here that the statement of the conjecture holds if we eliminate only one chosen runner. The proof uses a simple double-counting argument in the setting of finite fields. We also demonstrate that the original problem reduces to an analogous statement in particular ring Zn, where n is the sum of speeds of two distinct runners. In consequence we obtain a simple computational procedure for verifying the conjecture for any given set of integer speeds. Finally we derive some simple consequences of our results for coloring integer distance graphs. 相似文献
262.
Osama Abboud Konstantin Pussep Aleksandra Kovacevic Katharina Mohr Sebastian Kaune Ralf Steinmetz 《Multimedia Systems》2011,17(3):177-197
Peer-to-Peer (P2P) techniques for multimedia streaming have been shown to be a good enhancement to the traditional client/server
methods when trying to reduce costs and increase robustness. Due to the fact that P2P systems are highly dynamic, the main
challenge that has to be addressed remains supporting the general resilience of the system. Various challenges arise when
building a resilient P2P streaming system, such as network failures and system dynamics. In this paper, we first classify
the different challenges that face P2P streaming and then present and analyze the possible countermeasures. We classify resilience
mechanisms as either core mechanisms, which are part of the system, or as cross-layer mechanisms that use information from
different communication layers, which might inflict additional costs. We analyze and present resilience mechanisms from an
engineering point of view, such that a system engineer can use our analysis as a guide to build a resilient P2P streaming
system with different mechanisms and for various application scenarios. 相似文献
263.
Weirich Sebastian; Hoffmann Ferdinand; Mei?ner Lucia; Heinz Andreas; Bengner Thomas 《Canadian Metallurgical Quarterly》2011,25(6):806
Objective: It has been suggested that women have a better face recognition memory than men. Here we analyzed whether this advantage depends on a better encoding or consolidation of information and if the advantage is visible during short-term memory (STM), only, or whether it also remains evident in long-term memory (LTM). Method: We tested short- and long-term face recognition memory in 36 nonclinical participants (19 women). We varied the duration of item presentation (1, 5, and 10 s), the time of testing (immediately after the study phase, 1 hr, and 24 hr later), and the possibility to reencode items (none, immediately after the study phase, after 1 hr). Results: Women showed better overall face recognition memory than men (ηp2 = .15, p 相似文献
264.
Synergistic properties in hybrid materials can emerge if the inorganic matrix has an electronic influence on the organic constituents and vice versa. This paper describes the drastic effect of SiO2 in periodically ordered mesoporous organosilica materials (PMOs) on ethylene groups. A sophisticated, in situ solid‐state NMR spectroscopy study showed that the ozonolysis of ethylene groups follows an entirely different mechanism than is normal for organic, molecular groups. Ultimately, this leads to the topotactic transformation of the PMO material. Only if silicon is not in the alpha position to the double bond does it became possible to establish a new method to functionalize PMOs materials: the targeted scission of the ethylene group and the creation of functionalized pockets inside the pore walls of the mesoporous solid. 相似文献
265.
266.
Caroline Weidemann Sebastian Stahl Hermann Nirschl 《Food and Bioproducts Processing》2013,91(4):515-524
In this paper a new method for cleaning of filter media is presented, and the cleanability with different textures and surface finishes is compared. With the method described, it is possible to evaluate the quality of the cleaning process. According to the German VDMA standard cleaning test, riboflavin and malt extract are applied as model contaminants for evaluation of the cleaning results. To compare the cleanability of filter media with different properties and geometries the results are adapted to the law of mass transfer and to the Sherwood number, a dimensionless parameter describing the quality of a cleaning process. 相似文献
267.
Shelf life extension of whole Norway lobster Nephrops norvegicus using modified atmosphere packaging
Sebastian G. Gornik Amaya Albalat Chonchanok Theethakaew Douglas M. Neil 《International journal of food microbiology》2013
Once a nuisance by-catch, today the Norway lobster (Nephrops norvegicus) is a valuable UK fisheries commodity. Unfortunately, the species is very susceptible to quality deterioration post harvest as it quickly develops black spots and also spoils rapidly due to bacterial growth. Treatment with chemicals can stop the blackening and carefully monitored cold storage can result in a sensory shelf life of up to 6.5 days. The high susceptibility to spoilage greatly restricts the extent to which N. norvegicus can be distributed to retailers and displayed for sale. The application of modified atmosphere (MA) could be extremely beneficial, allowing the chilled product to stay fresh for a long period of time, thus ensuring higher sales. In the present study, we identified a gas mix for the MA packaging (MAP) of whole N. norvegicus lobster into 200 g retail packs. Our results show that a shelf life extension to 13 days can be achieved when retail packs are stored in MAP at 1 °C. Effectiveness of the MAP was evaluated by using a newly developed QIM for MA-packaged whole N. norvegicus and also by analyzing bacterial plate counts. Changes in the microflora and effects of different storage temperatures on the quality of the MA packs are also presented. The main specific spoilage organism (SSO) of modified atmosphere packaged Norway lobster is Photobacterium phosphoreum. 相似文献
268.
Sumesh George Mailadil Thomas Sebastian 《Journal of the European Ceramic Society》2010,30(12):2585-2592
The Li2Mg1?xZnxTi3O8 (x = 0–1) and Li2A1?xCaxTi3O8 (A = Mg, Zn and x = 0–0.2) ceramics are synthesized by solid-state ceramic route and the microwave dielectric properties are investigated. The Li2MgTi3O8 ceramic shows ?r = 27.2, Qu × f = 42,000 GHz, and τf = (+)3.2 ppm/°C and Li2ZnTi3O8 has ?r = 25.6, Qu × f = 72,000 GHz, and τf = (?)11.2 ppm/°C respectively when sintered at 1075 °C/4 h. The Li2Mg0.9Zn0.1Ti3O8 dielectric ceramic composition shows the best dielectric properties with ?r = 27, Qu × f = 62,000 GHz, and τf = (+)1.1 ppm/°C. The effect of Ca substitution on the structure, microstructure and microwave dielectric properties of Li2A1?xCaxTi3O8 (A = Mg, Zn and x = 0–0.2) has also been investigated. The materials reported in this paper are excellent in terms of dielectric properties and cost of production compared to commercially available high Q dielectric resonators. 相似文献
269.
270.