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61.
Trine Krogh Kristoffersen 《Mathematical Methods of Operations Research》2005,62(2):255-274
We consider a linear two-stage stochastic program. Whereas optimization in the traditional setting is based solely on expectation,
we include risk measures reflecting dispersions of the random objective. Presenting the mean-risk models, we aim to extend
existing results for the expectation-based model. In particular, we discuss structural properties such as continuity, differentiability
and convexity and address stability issues. Furthermore, we propose algorithmic treatment with a slight variation of the L-shaped
method 相似文献
62.
T. Eichten H. Faissner F.J. Hasert S. Kabe W. Krenz J. Von Krogh J. Morfin K. Schultze G.H. Bertrand-Coremans J. Sacton W. Van Doninck P. Vilain D.C. Cundy D. Haidt M. Jaffre S. Natali P. Musset J.B.M. Pattison W.G. Scott 《Physics letters. [Part B]》1973,46(2):274-280
The v and nucleon total cross-sections have been determined as a function of energy using a sample of 2500 v and 950 event. The results are compared with predictions of scaling and charge symmetry hypotheses. 相似文献
63.
K. E. Kongshaug S. Pedersen-Bjergaard K. E. Rasmussen M. Krogh 《Chromatographia》1999,50(3-4):247-252
Summary Impurity profiling of ecstacy and amphetamine seizures was accomplished by solid-phase microextraction (SPME) combined with
capillary gas chromatography (GC). Samples were dissolved in 0.1 M aqueous acetate buffer (pH 5.0) as the only manual operation
and subsequently subjected to SPME-GC. Ecstacy tablets were analyzed by head-space SPME to avoid contamination of SPME fibers
with insoluble tablet components, while illicit amphetamine powders were exposed to immersed SPME. A SPME fiber of polydimethylsiloxane-divinylbenzene
was found to provide excellent extraction of both polar and non-polar impurities. For both illicit ecstacy and amphetamine,
complex impurity profiles were obtained by SPME providing a high information content. For ecstacy, profiles (relative peak
areas) were repeatable within 2.2 to 12.6% RSD (n=6) while similar data on amphetamine varied between 2.0 and 10.9% RSD (n=6).
No carry-over was observed although each fiber was used for 50 to 100 extractions. 相似文献
64.
65.
E.A. Petruska D.V.S. Muthu S. Carlson A.M. Krogh Andersen L. Ouyang M.B. Kruger 《Solid State Communications》2010,150(5-6):235-239
High-pressure Raman and mid-infrared spectroscopic studies were carried out on ZrP2O7 to 23.2 and 13 GPa respectively. In the pressure range 0.7–4.3 GPa the lattice mode at 248 cm?1 disappears, new modes appear around 380 and 1111 cm?1 and the strong symmetric stretching mode at 476 cm?1 softens, possibly indicating a subtle phase transition. Above 8 GPa all the modes broaden, and all of the Raman modes disappear beyond 18 GPa. On decompression from the highest pressure, 23.2, to 0 GPa all of the modes reappear but with larger full width at half maximum. Lattice dynamics of the high temperature phase of ZrP2O7 were studied using first principles method and compared with experimental values. 相似文献
66.
67.
H. Deden F.J. Hasert W. Krenz J. Von Krogh D. Lanske J. Morfin K. Schultze H. Weerts G.H. Bertrand-Coremans J. Sacton W. Van Doninck P. Vilain D.C. Cundy D. Haidt M. Jaffre S. Natali J.B.M. Pattison W.G. Scott 《Nuclear Physics B》1975,85(2):269-288
High-energy exclusive and inclusive cross sections are discussed in terms of their dependence on the transverse-position variables (impact parameters) of incident and outgoing particles. The objective is to clarify the points of conflict and agreement of various models with each other and with intuitive ideas based on macroscopic collisions. First the impact parameter representation of states and amplitudes is reviewed. New impact parameter conservation laws and sum rules are derived from Lorentz invariance. The generalized optical theorem of Mueller is extended to give the impact parameter distribution of produced particles. Mueller-Regge behaviour is shown to imply three-dimensional limiting fragmentation in (impact parameter, rapidity)- space and a specific linear structure of the final-state particle density in the central region of this space. The predictions of weak- and strong-coupling multiperipheral models, the φ3 ladder eikonal model and the dual resonance model are presented, with emphasis on the dependence of average multiplicity on impact parameter and the dependence of mean square impact parameter on multiplicity. Special techniques for strong-coupling multiperipheral models are used to study the breakdown of the random-walk impact-parameter structure of the weak-coupling case, and to show explicitly that the average multiplicity is a decreasing function of impact parameter in the strongly coupled ABFST model. 相似文献
68.
We have studied the fragmentation behaviour of short, singly protonated oligoribonucleotides on a MALDI Qq-TOF instrument with the aim of using this instrumental set-up to characterise modifications of RNA molecules. Individual ion species from enzymatically generated mixtures were isolated in one quadrupole and subjected to collision-induced dissociation in a second quadrupole followed by separation of the resulting product ions in an orthogonal time-of-flight mass analyser. Complex spectra were generally observed with nearly all types of cleavages along the phosphodiester backbone and of the N-glycosidic bonds (and combinations of these) occurring, albeit at different relative intensities. The most labile part of the backbone was found to be the 5'-P-O bond, resulting in c- and y-ions. Loss of neutral cytosine and guanine occurred equally often, whereas neutral loss of adenosine was less prevalent. Loss of uracil, either neutral or charged species, was not observed. Because the fragmentation pattern observed here is significantly different from what has been reported for singly protonated oligodeoxyribonucleotides, we suggest that the 2'-substituent in the sugar plays a central role in the fragmentation mechanisms of nucleic acids. Finally, we used the acquired knowledge about oligoribonucleotide fragmentation to characterise an in vivo methylated oligoribonucleotide by tandem mass spectrometry. 相似文献
69.
F.J. Hasert W. Krenz J. Von Krogh D. Lanske J. Morfin K. Schultze H. Weerts G.H.B. Coremans H. Mulkens J. Sacton W. Van Doninck D.C. Cundy D. Haidt P. Musset A. Norton J.B.M. Pattison F. Romano A. Rousset A.J. Segar 《Physics letters. [Part B]》1975,59(5):485-489
A study is presented of single πo production in neutrino and antineutrino interactions in Gargamelle filled with freon CF3Br. Limits on the neutral to charged current cross-section ratios and are found to be at 68% confidence level. 相似文献
70.