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51.
Heinz Prüfer 《Mathematische Zeitschrift》1923,17(1):35-61
Ohne Zusammenfassung 相似文献
52.
Dual method for the solution of a one-stage stochastic programming problem with random RHS obeying a discrete probability distribution 总被引:1,自引:0,他引:1
A. Prékopa 《Mathematical Methods of Operations Research》1990,34(6):441-461
In this paper we present a method for the solution of a one stage stochastic programming problem, where the underlying problem is an LP and some of the right hand side values are random variables. The stochastic programming problem that we formulate contains probabilistic constraint and penalty, incorporated into the objective function, used to penalize violation of the stochastic constraints. We solve this problem by a dual type algorithm. The special case where only penalty is used while the probabilistic constraint is disregarded, the simple recourse problem, was solved earlier by Wets, using a primal simplex algorithm with individual upper bounds. Our method appears to be simpler. The method has applications to nonstochastic programming problems too, e.g., it solves the constrained minimum absolute deviation problem.
Zusammenfassung In dieser Arbeit wird eine Methode vorgestellt zur Lösung einstufiger stochastischer Programme, wobei das zugrundeliegende Problem ein LP mit zufälligen rechten Seiten darstellt. Das resultierende stochastische Programm enthält Wahrscheinlichkeitsrestriktionen und Strafterme, letztere innerhalb der Zielfunktion zur Bestrafung von Abweichungen in den stochastischen Restriktionen. Wir lösen dieses Problem mit einem dualen Algorithmus. Der Spezialfall, in dem ausschließlich Strafterme benutzt werden und Wahrscheinlichkeitsrestriktionen unberücksichtigt bleiben, d.h. das einfache Kompensationsmodell, wurde bereits früher von Wets mittels eines primalen Simplex-Algorithmus mit einzelnen oberen Schranken gelöst. Unsere Methode scheint einfacher zu sein. Die Methode ist auch auf nicht-stochastische Programme anwendbar, z.B. auf das Problem minimaler absoluter Abweichungen von Nebenbedingungen.相似文献
53.
We demonstrate that a more efficient redox hydrogel structure can be achieved by engineering the size and the surface charge of the bioelectrocatalyst. Deglycosylated glucose oxidase (GOx) modified electrode exhibits higher current density than native GOx, for the same molar composition of the hydrogel. This improvement is very likely due to a more efficient hydrogel structure rather than a better intrinsic electron transfer between the FAD/FADH2 redox center and the redox mediator. 相似文献
54.
55.
S. Szpikowski P. Klosowski L. Próchniak 《Zeitschrift für Physik A Hadrons and Nuclei》1990,335(3):289-292
We discuss the quadrupole electric transitions in the frame of the supersymmetric model for light nuclei (s —d shell). We present the construction of an isoscalar transition operator based on the assumption of the dynamicalSO BF (6) symmetry. Theoretical transition probabilities for nuclei belonging to the supermultiplet characterized by a particle numberN=5 show quite a good agreement with experimental data. 相似文献
56.
M. -G. Porquet Ts. Venkova A. Astier I. Deloncle A. Prévost F. Azaiez A. Buta D. Curien O. Dorvaux G. Duchêne B. J. P. Gall F. Khalfallah I. Piqueras M. Rousseau M. Meyer N. Redon O. Stézowski R. Lucas A. Bogachev 《The European Physical Journal A - Hadrons and Nuclei》2006,28(2):153-159
The 87Kr nucleus has been produced as fission fragment in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. High-spin states of this neutron-rich isotope have been
identified for the first time. Its level scheme has been obtained up to 6.3MeV excitation energy and spin I ∼ 23/2ℏ. Its structure is interpreted by analogy with those of the heavier isotones. The proposed configurations involve
both proton and neutron excitations from several sub-shells located close to the Fermi levels, particularly νd5/2, πp3/2f5/2 and πg9/2. Moreover, a revised spin value of 5/2- for the 87Br ground state is proposed. 相似文献
57.
Csilla Mišľanová Jana Príbojová Martina Valachovičová Zuzana Žilinská 《Analytical letters》2017,50(15):2359-2368
Cyclosporine, tacrolimus, sirolimus, and everolimus are commonly used immunosuppressants following organ transplantation. Their monitoring is used to determine the optimal dose for therapeutic effectiveness and minimize toxicity. High-performance liquid chromatographic–tandem mass spectrometry with positive electrospray ionization and multiple reaction monitoring mode was validated for the determination of cyclosporine A, tacrolimus, sirolimus, and everolimus in whole blood. A C18 analytical column was employed with a gradient elution of pH 4.0 aqueous 10?mmol/L ammonium acetate and acetonitrile. For the pretreatment of whole blood, simple protein precipitation was used with methanol:zinc sulfate. The calibration curves were linear from 20.0 to 1000?ng/mL for cyclosporine A, 1.0 to 50?ng/mL for tacrolimus and sirolimus, and 1.0 to 30?ng/mL for everolimus. The intra-assay precision and inter-assay precision were less than 15%. The method provides reliable and reproducible results according to the linearity, precision, accuracy, recovery, and matrix effects. The method has been introduced to routine clinical practice in Slovakia for the determination of immunosuppressants in patients after kidney transplantation. 相似文献
58.
Birgit Prüger Dr. Gretchen E. Hofmeister Prof. Dr. Christian Borch Jacobsen David G. Alberg Prof. Dr. Martin Nielsen Dr. Karl Anker Jørgensen Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(12):3783-3790
Transition‐metal‐free formal Sonogashira coupling and α‐carbonyl arylation reactions have been developed. These transformations are based on the nucleophilic aromatic substitution (SNAr) of β‐carbonyl sulfones to electron‐deficient aryl fluorides, producing a key intermediate that, depending on the reaction conditions, gives the aromatic alkynes or α‐aryl carbonyl compounds. The development of these reactions is presented and, based on investigations under basic and acidic conditions, mechanisms have been proposed. To develop the formal Sonogashira coupling further, a milder, two‐step protocol is also disclosed that expands the reaction concept. The scope of these reactions is demonstrated for the synthesis of Sonogashira and α‐carbonyl arylated products from a range of electron‐deficient aryl fluorides with a variety of functional groups and aryl‐, heteroaryl‐, alkyl‐, and alkoxy‐substituted sulfone nucleophiles. These transition‐metal‐free reactions complement the metal‐catalyzed versions in terms of substitution patterns, simplicity, and reaction conditions. 相似文献
59.
60.
A. Perjéssy H. K. Al‐Amood G. F. Fadhil N. Prónayová 《Journal of Physical Organic Chemistry》2011,24(2):140-146
A series of substituted chlorinated chalcones namely, 3‐(2,4‐dichlorophenyl)‐1‐(4′‐X‐phenyl)‐2‐propen‐1‐one, have been synthesized, X being H, NH2, OMe, Me, F, Cl, CO2Et, CN, and NO2. Dual substituent parameter (DSP) models of 13C NMR chemical shift (CS) have revealed that π‐polarization concept could be utilized to explain the reverse field effect at CO, the enhanced substituent field effect at CO, C‐2, and C‐5, and the decreased sensitivity of substituent field effect at C‐6. Chlorine atoms dipole direction at the benzylidene ring either enhances or reduces substituent effect depending on how they couple with the substituent dipole at the probe site. The correlation of 13C NMR CS of C‐2, C‐5, and C‐6 with σ and σ indicates that chlorine atoms in the benzylidine ring deplete the ring from charges. Both MSP of Hammett and DSP of Taft 13C NMR CS models give similar trends of substituent effects at C‐2, C‐5, and C‐6. However, the former fail to give a significant correlation for CO and C‐6 13C NMR CS. MSP of σq and DSP of Taft and Reynolds models significantly correlated 13C NMR CS of Cβ. MSP of σq fails to correlate C‐1′ 13C NMR CS. Investigation of 13C NMR CS of non‐chlorinated chalcones series: 3‐phenyl‐1‐(4′‐X‐phenyl)‐2‐propen‐1‐one has revealed similar trends of substituent effects as in the chlorinated chalcones series for C‐1′, CO, Cα, and Cβ. In contrast, the substituent effect of the non‐chlorinated chalcone series at C‐2, C‐5, and C‐6 did not correlate with any substituent constant. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献