Analytic Decision Rules for Financial Stochastic Programs

Contemporary financial stochastic programs typically involve a trade-offbetween return and (downside)-risk. Using stochastic programming we characterize analytically (rather than numerically) the optimal decisions that follow from characteristic single-stage and multi-stage versions of such programs. The solutions are presented in the form of decision rules with a clear-cut economic interpretation. This facilitates transparency and ease of communication with decision makers. The optimal decision rules exhibit switching behavior in terms of relevant state variables like the assets to liabilities ratio. We find that the model can be tuned easily using Value-at-Risk (VaR) related benchmarks. In the multi-stage setting, we formally prove that the optimal solution consists of a sequence of myopic (single-stage) decisions with risk-aversion increasing over time. The optimal decision rules in the dynamic setting therefore exhibit identical features as in the static context

Radio frequency studies in the NASA Lewis Bumay Torus

The fluctuations in potential of the plasma in the NASA Lewis Bumpy Torus were observed using capacitive probes over frequencies from 1 kHz to 25 MHz and a wide range of operating conditions. The spectra were found to differ greatly above and below a background gas pressure of 3.0.000034 torr deuterium. Above this pressure the spectrum was dominated by the ion spoke frequency and a spectral index was defined. Below this pressure the spectrum below 200 kHz was lower in lower in amplitude by a factor of ten and no spectral index could be defined. At these lower pressures, fluctuations that appeared to be ion spokes were observed, but had a dependence of frequency on operating conditions which was previously unreported

The pronunciation of Latin

Thesis (M.A.)--Boston Universit

L'innovation mise à l'épreuve. Une expérience de télévision payante

Rapport CSI-Lyonnaise des Eaux-DumezIl ne suffit pas d'inventer, il faut encore capter des clients, convaincre des partenaires de s'emparer de l'idée ou du dispositif technique. Or voici que l'innovation étudiée ici devance largement ce discours : nos innovateurs sont convaincus, certes par la qualité et la valeur de leur dispositif ; mais ils mettent surtout leur énergie à construire des réseaux dans lesquels il va pouvoir s'insérer, ils accordent la première place à la manière de le commercialiser, ils mettent en place de multiples tests, ils travaillent à convaincre les différents partenaires de tous les avantages qu'il peut apporter. Aurions-nous découvert des innovateurs parfaits — nous voulons dire plus sociologues que techniciens ? Notre innovation est un service : le monde des services serait-il plus sensible à la construction des marchés que celui des techniques et des biens ? Dans le cadre d'une recherche collective sur l'innovation de service dans différents groupes, ce travail analyse une expérience de télévision en “pay per view”, développée par la filiale Communications de la Lyonnaise des Eaux-Dumez

Electromagnetic wave speed in polar ice: Validation of the CMP technique with high resolution dielectric-profiling and gamma-density measurements

The accuracy of the traveltime-velocity and traveltime-depth profile derived from ground-penetrating radar (GPR) common-midpoint (CMP) surveys at different frequencies is investigated for the first time ever by direct comparison with the profile calculated from high resolution dielectric-profiling (DEP) ice core data.In addition, we compare two traveltime profiles calculated from ice core density data by means of different dielectrical mixture models with the DEP based profile.CMP surveys were carried out at frequencies of 25, 50, 100 and 200 MHz near the new European deep drilling site DML05 in Dronning Maud Land, Antarctica, during the 1998/99 field season.An improved scanning capacitor for high resolution DEP and a Gamma-densiometer for density measurements were used to determine thecomplex dielectric constant and the density at 5 mm increments along the ice core B32, retrieved in 1997/98 at DML05.The comparisons with DEP and density based velocity series show that the CMP velocity series are slightly higher, but asymptotically approach the core based velocities with depth.Root-mean-square differences of the DEP velocity series range between 8% for the 25 MHz CMP and 2% in the case of the 200 MHz survey.Density based velocities differ from the DEP velocities by less than 1%.The traveltime-depth series calculated from the interval velocities show a better agreement between all series than the velocity series.Differences are between 5.7 and 1.4% for the 25 and 200 MHz CMP measurements, and less than 0.6% for the density data.Based on these comparisons we evaluate the accuracy with which the depth of electromagnetic reflectors observed in common-offset profiles can be determined and discuss reasons for the observed differences between CMP- and core based profiles.Moreover, we compare the errors determined from the field measurements with those estimated from GPR system characteristics to provide a measure that can be used to estimate the accuracy of GPR analyses for the planning of GPR campaigns.Our results show that CMP surveys are a useful technique to determine the depth of radar reflectors in combination with common-offset measurements, especially on a region-wide basis

Computer program for preliminary design and analysis of V/STOL tip-turbine fans

Computer program for design and analysis of V/STOL tip turbine fan

La città diffusa dopo la crescita. Dinamiche di mutazione emergenti e prospettive per un progetto di ricomposizione urbanistica

Diversi ambienti insediativi al centro-nord del paese, connotati da fenomeni di dispersione insediativa, mostrano i sintomi di una contrazione degli usi che investe tanto i tradizionali spazi produttivi quanto degli spazi dell’abitare. Il capannone e la casa di famiglia, sottoutilizzati, testimoniano l’affievolirsi dei processi di mobilitazione e di autopromozione all’origine di queste forme urbane. Ciò non significa che la città diffusa abbia smesso di crescere. Nuove esigenze spaziali e qualitative si rivolgono a format di offerta che continuano a consumare suolo entro logiche diverse da quelle del passato: insediamenti insularizzati e “generici”, senza alcun rapporto col suolo, fatta eccezione per la localizzazione in prossimità di nodi infrastrutturali. In questo quadro, le dinamiche non governate di sottoutilizzo e dismissione possono favorire uno scenario in cui rovine precoci convivono con nuove edificazioni, erodendo fatalmente gli ultimi suoli liberi di contesti già molto urbanizzati. Questo contributo ragiona ad una ipotesi alternativa, in cui si tenta di integrare processi di decadimento e di produzione del nuovo, e di ricomporre i materiali urbani esistenti entro prospettive di sostenibilità economica e finanziaria

Baladen itzultze eta moldatze moduez

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