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991.
992.
This paper provides extensions of the work on subsampling by Bertail et al. in J. Econ. 120:295–326 (2004) for strongly mixing case to weakly dependent case by application of the results of Doukhan and Louhichi in Stoch. Proc.
Appl. 84:313–342 (1999). We investigate properties of smooth and rough subsampling estimators for sampling distributions of converging and extreme
statistics when the underlying time series is η- or λ-weakly dependent. 相似文献
993.
Paul Gardiner 《Construction Management & Economics》2013,31(11):1011-1012
994.
Paul E. Mertes 《Datenschutz und Datensicherheit - DuD》2010,34(9):633-637
Die aktuelle E-Mail-Rechtssprechung macht es deutlich: Die Zeit der Beliebigkeit in der E-Mail-Kommunikation ist vorbei: E-Mails
haben sich zu einer ernstzunehmenden und rechtswirksamen Kommunikationsform entwickelt. 相似文献
995.
Shichao Ding Paul A. MeehanWilliam J.T. Daniel 《Journal of Materials Processing Technology》2011,211(3):376-381
Millipede forming, a novel sheet metal forming method, has been proposed and developed recently to overcome fundamental limitations in conventional roll forming. For this new method, there are two main aspects: use of an optimal transitional surface and implementation of a method to feed the strip through the transition surface. Achieving the optimal transitional surface involves defining the change of surface shape between a flat strip and a final shaped product conceptualised to the strip's mid-surface, regardless of the strip's thickness.In this paper, one method of implementing a transition surface, Millipede forming, is introduced. A prototype has been built to demonstrate the working principle and can be used to produce some simple profiles, within a short forming length of 200 mm. 相似文献
996.
Leticia Cubo Dr. Michael Groessl Dr. Paul J. Dyson Prof. Adoración G. Quiroga Dr. Carmen Navarro‐Ranninger Prof. Angela Casini Dr. 《ChemMedChem》2010,5(8):1335-1343
The reactivity of three cytotoxic trans‐PtII complexes bearing aliphatic amine ligands, with transferrin and single‐stranded oligonucleotides as DNA models, was investigated by ESI‐MS and the results obtained are discussed in comparison with cisplatin. Tandem MS studies provided additional information on the preferential Pt binding sites. To determine whether trans‐PtII complexes can migrate from a peptide to an oligonucleotide, transfer experiments were also performed using ESI‐MS, and competitive binding of the trans‐PtII complexes toward a model peptide and different oligonucleotides was also investigated. Significant differences in the reactivity of the trans complexes with respect to cisplatin were observed. In general, adduct formation with the selected peptide is favored for the trans compounds, whereas cisplatin shows a preference for oligonucleotides, especially if adjacent G–G residues are present. The results are discussed in relation to the possible mechanism of action of the trans‐PtII complexes. 相似文献
997.
Christopher J. Shepherd Gareth J. Appleby-Thomas James M. Wilgeroth Paul J. Hazell Derek F. Allsop 《International Journal of Impact Engineering》2011,38(12):981-988
The effects of projectile penetration into soft tissue are often studied using the tissue simulant ballistic soap. Consequently, a full understanding of the high strain-rate response of ballistic soap is desirable. Using the plate-impact technique, key shock parameters have been measured for impacts in the range 81–968 m/s, allowing derivation of the Hugoniot equation-of-state for soap in the US–uP and σX–uP planes. A polynomial Hugoniot relationship was found in the US–uP plane, with the general form US = 1.96 + 2.41uP − 0.72uP2 (ρ0 = 1.107 g/cc). Further, embedded lateral manganin stress gauges were employed to interrogate the evolution of lateral stress within the soap. A gradient in lateral stress, whose magnitude increased incrementally with impact stress, was apparent behind the shock for σX >1 GPa. It is proposed that at higher values of σX, increased compression of hydrocarbon chains acts to increase the materials resistance to shear, a phenomenon consistent with steric hindrance. 相似文献
998.
999.
1000.
We developed an unmanned air vehicle (UAV) suitable for small parabolic-flight experiments. The flight speed of 100 m s − 1 is sufficient for zero-gravity parabolas of 16 s duration. The flight path’s length of slightly more than 1 km and 400 m
difference in altitude is suitable for ground controlled or supervised flights. Since this fits within the limits set for
model aircraft, no additional clearance is required for operation. Our UAV provides a cost-effective platform readily available
for low-g experiments, which can be performed locally without major preparation. A payload with a size of up to 0.9 ×0.3 ×0.3 m3 and a mass of ∼5 kg can be exposed to 0 g
0–5 g
0, with g
0 being the gravitational acceleration of the Earth. Flight-duration depends on the desired acceleration level, e.g. 17 s at
0.17 g
0 (lunar surface level) or 21 s at 0.38 g
0 (Martian surface level). The aircraft has a mass of 25 kg (including payload) and a wingspan of 2 m. It is powered by a jet
engine with an exhaust speed of 450 m s − 1 providing a thrust of 180 N. The parabolic-flight curves are automated by exploiting the advantages of sophisticated micro-electronics
to minimize acceleration errors. 相似文献