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91.
92.
Miguel A. Goberna Mercedes Larriqueta Virginia N. Vera de Serio 《Journal of Computational and Applied Mathematics》2008
Many mathematical programming models arising in practice present a block structure in their constraint systems. Consequently, the feasibility of these problems depends on whether the intersection of the solution sets of each of those blocks is empty or not. The existence theorems allow to decide when the intersection of non-empty sets in the Euclidean space, which are the solution sets of systems of (possibly infinite) inequalities, is empty or not. In those situations where the data (i.e., the constraints) can be affected by some kind of perturbations, the problem consists of determining whether the relative position of the sets is preserved by sufficiently small perturbations or not. This paper focuses on the stability of the non-empty (empty) intersection of the solutions of some given systems, which can be seen as the images of set-valued mappings. We give sufficient conditions for the stability, and necessary ones as well; in particular we consider (semi-infinite) convex systems and also linear systems. In this last case we discuss the distance to ill-posedness. 相似文献
93.
Ericka Santacruz Gabriela Huelgas Sandra K. Angulo Virginia M. Mastranzo Simón Hernández-Ortega Judit A. Aviña Eusebio Juaristi Cecilia Anaya de Parrodi Patrick J. Walsh 《Tetrahedron: Asymmetry》2009,20(24):2788-2794
New chiral thioureas 1–8 containing 1,2-ethylendiamine or trans-1,2-diaminocyclohexane as the carbon skeleton, and containing an (S)-α-phenylethyl group have been prepared (79–98% yield). Thioureas 1–8 were used as ligands for the zinc-based catalyzed asymmetric hydrosilylation of acetophenone with polymethylhydrosiloxane (PMHS). The best result was achieved with monothiourea 1 (up to 75% ee), in toluene and a catalyst load of 5 mol %. 相似文献
94.
95.
Virginia R. Young 《Insurance: Mathematics and Economics》2008,42(2):691-703
We develop a pricing rule for life insurance under stochastic mortality in an incomplete market by assuming that the insurance company requires compensation for its risk in the form of a pre-specified instantaneous Sharpe ratio. Our valuation formula satisfies a number of desirable properties, many of which it shares with the standard deviation premium principle. The major result of the paper is that the price per contract solves a linear partial differential equation as the number of contracts approaches infinity. One can represent the limiting price as an expectation with respect to an equivalent martingale measure. Via this representation, one can interpret the instantaneous Sharpe ratio as a market price of mortality risk. Another important result is that if the hazard rate is stochastic, then the risk-adjusted premium is greater than the net premium, even as the number of contracts approaches infinity. Thus, the price reflects the fact that systematic mortality risk cannot be eliminated by selling more life insurance policies. We present a numerical example to illustrate our results, along with the corresponding algorithms. 相似文献
96.
Tyihk Ern Mricz gnes M. Ott Pter G. Hajnos Michal L. Gowniak Kazimierz 《平面色谱法杂志一现代薄层色谱法》2008,21(5):331-336
JPC – Journal of Planar Chromatography – Modern TLC - The accumulation of hydrogen peroxide (H2O2) is an early and crucial step in paclitaxel-induced cancer cell death before commitment... 相似文献
97.
E Mincsovics Gy Kátay P G Ott Zs Király-Véghely Á M Móricz E Tyihák 《Chromatographia》2005,62(13):s51-s56
The first results of the combination of BioArena and OPLC with flowing eluent wall technique (FEW) show an especially attractive solution of the detection of antimicrobial activity and compound isolation based on peak collection. Because of the different separation mechanisms applied for on-line FEW–OPLC isolation of red wine constituents and for further off-line OPLC investigation of fractions, the combined system yields high selectivity. 相似文献
98.
Lucas Montero De Espinosa Juan C. Ronda Marina Galià Virginia Cádiz Michael A.R. Meier 《Journal of polymer science. Part A, Polymer chemistry》2009,47(21):5760-5771
The acyclic diene metathesis (ADMET) polymerization of a phosphorus‐containing α,ω‐diene prepared from a plant oil derived building block is reported. Different ruthenium based metathesis catalysts and conditions were tested to optimize the ADMET polymerization of this monomer. Undecylenyl undecenoate was used as fully renewable comonomer to obtain polyesters with different phosphorus contents and to increase the renewable content of the final polymers. Copolymerization caused marked variations in the molecular weights leading to polyesters from 6 to 38 KDa. The effect of the ADMET polymerization temperature in the thermal properties of the copolymers was studied and their thermal degradation and flame retardant properties were evaluated. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5760–5771, 2009 相似文献
99.
M. Ott 《Fresenius' Journal of Analytical Chemistry》1938,113(3-4):81-83
Ohne Zusammenfassung 相似文献
100.