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For compact Calabi-Yau geometries with D5-branes we study N = 1 effective super-potentials depending on both open-and closed-string fields. We develop methods to derive the open/closed Picard-Fuchs differential equations, which control D5-brane deformations as well as complex structure deformations of the compact Calabi-Yau space. Their solutions encode the(More)
This paper provides a review of the available tuning guidelines for model predictive control, from theoretical and practical perspectives. It covers both popular dynamic matrix control and generalized predictive control implementations, along with the more general state-space representation of model predictive control and other more specialized types, such(More)
In this work we compute relative periods for B-branes, realized in terms of divisors in a compact Calabi-Yau hypersurface, by means of direct integration. Although we exemplify the method of direct integration with a particular Calabi-Yau geometry, the recipe automatically generalizes for divisors in other Calabi-Yau geometries as well. From the calculated(More)
The majority of models of inflation in string theory predict an absence of measurable grav-itational waves, r << 10 −3. The most promising proposals for making string theoretic models that yield measurable tensor fluctuations involve axion fields with slightly broken shift symmetry. We consider such models in detail, with a particular focus on the N-flation(More)
A novel framework to model the chronology of incidents is presentedsdepicting the relationship of initiating events with the various regulating and protection systems of the processseventually leading to consequences, varying from zero to high severities. The key premise is that the departures and subsequent returns of process and product quality variables,(More)
The increasingly aggressive global competition for the production of higher quality polymer products at lower costs, along with a general trend away from new capital investments in the U.S., has placed considerable pressure on the process engineers in the U.S. to operate the existing polymer plants more efficiently and to use the same plant for the(More)
This paper presents computational evidence for the occurrence of diradical mechanism of self-initiation in thermal polymerization of methyl methacrylate. Two self-initiation mechanisms of interest were explored with first-principles density functional theory calculations. Singlet and triplet potential energy surfaces were constructed. The formation of two(More)
Part II presents step (iii) of the dynamic risk analysis methodology; that is, a novel Bayesian analysis method that utilizes near-misses from distributed control system (DCS) and emergency shutdown (ESD) system databases—to calculate the failure probabilities of safety, quality, and operability systems (SQOSs) and probabilities of occurrence of incidents.(More)
In this study, the mechanism of self-initiation in spontaneous thermal polymerization of ethyl and n-butyl acrylate is explored using first-principles calculations. Density functional theory (with B3LYP functional and 6-31G* basis set) was used to study [4 + 2] and [2 + 2] cycloaddition reactions on the singlet and triplet potential energy surfaces.(More)