Prediction of explosive yield and other characteristics of liquid propellant rocket explosions Final report

Explosive hazards and yield predictions for liquid rocket propellant

Distorted Copulas: Constructions and Tail Dependence

Given a copula C, we examine under which conditions on an order isomorphism ψ of [0, 1] the distortion C ψ: [0, 1]2 → [0, 1], C ψ(x, y) = ψ{C[ψ−1(x), ψ−1(y)]} is again a copula. In particular, when the copula C is totally positive of order 2, we give a sufficient condition on ψ that ensures that any distortion of C by means of ψ is again a copula. The presented results allow us to introduce in a more flexible way families of copulas exhibiting different behavior in the tails

Western Wheatgrass Recovery From Drought

Native grasses are predictably taller in wet years than in dry years and their density also increases with favorable precipitation. These responses of western wheatgrass are more dramatic on mechanically treated rangeland when precipitation is adequate. Measurements taken in July 1991 confirmed that western wheatgrass was slightly taller and density at least two times greater on mechanically treated claypan soils compared with untreated soils 13 and 18 years following treatment. Increases of this magnitude constitute a potentially greater carrying capacity which livestock producers should be prepared to utilize. This report briefly summarizes the effects of mechanical treatment on height and density of western wheatgrass 13 and 18 years following treatment and in a wet year following several dry years

Conjunctors and their residual implicators: characterizations and construction methods

In many practical applications of fuzzy logic it seems clear that one needs more flexibility in the choice of the conjunction: in particular, the associativity and the commutativity of a conjunction may be removed. Motivated by these considerations, we present several classes of conjunctors, i.e. binary operations on $[0,1]$ that are used to extend the boolean conjunction from $\{0,1\}$ to $[0,1]$, and characterize their respective residual implicators. We establish hence a one-to-one correspondence between construction methods for conjunctors and construction methods for residual implicators. Moreover, we introduce some construction methods directly in the class of residual implicators, and, by using a deresiduation procedure, we obtain new conjunctors

Inclusion of ionic interactions in force field calculations of charged biomolecules – DNA structural transitions.

The potential of mean force (PMF) approach for treating polyion–diffuse ionic cloud interactions [D. M. Soumpasis (1984) Proceedings of the National Academy of Sciences USA81, 5116–5120] has been combined with the AMBER force field describing intramolecular interactions. The resultant generalized AMBER-PMF force field enables one to treat the conformational stabilities and structural transitions of charged biomolecules in aqueous electrolytes more realistically. For example, we have used it to calculate the relative stabilities of the B and Z conformations of d(C-G)6, and the B and heteronomous (H) conformations of dA12 · dT12, as a function of salt concentration. In the case of d(C-G)6, the predicted B–ZI transition occurs at 2.4M and is essentially driven by the phosphate-diffuse ionic cloud interactions alone as suggested by the results of earlier PMF calculations. The ZII conformer is less stable than the B form under all conditions. It is found that the helical parameters of the refined B and Z structures change with salt concentration. For example, the helical rise of B-DNA increases about 10% and the twist angle decreases by the same amount above 1M NaCl. In the range of 0.01–0.3M NaCl, the H form of dA12 · dT12 is found to be more stable than the B form and its stability increases with increasing salt concentration. The computed greater relative stability of the H conformation is likely due to noninclusion of the free energy contribution from the spine of hydration, a feature presumed to stabilize the B form of this sequence

Copulas constructed from horizontal sections

In analogy with the study of copulas whose diagonal sections have been fixed, we study the set $\mathcal{C}_h$ of copulas for which a horizontal section $h$ has been given. We first show that this set is not empty, by explicitly writing one such copula, which we call \textit{horizontal copula}. Then we find the copulas that bound both below and above the set $\mathcal{C}_h$. Finally we determine the expressions for Kendall's tau and Spearman's rho for the horizontal and the bounding copulas

Reanalysis of the FEROS observations of HIP 11952

Aims. We reanalyze FEROS observations of the star HIP 11952 to reassess the existence of the proposed planetary system. Methods. The radial velocity of the spectra were measured by cross-correlating the observed spectrum with a synthetic template. We also analyzed a large dataset of FEROS and HARPS archival data of the calibrator HD 10700 spanning over more than five years. We compared the barycentric velocities computed by the FEROS and HARPS pipelines. Results. The barycentric correction of the FEROS-DRS pipeline was found to be inaccurate and to introduce an artificial one-year period with a semi-amplitude of 62 m/s. Thus the reanalysis of the FEROS data does not support the existence of planets around HIP 11952.Comment: 7 pages, 8 figures, 1 tabl