Shuttle TPS thermal performance and analysis methodology

Thermal performance of the thermal protection system was approximately as predicted. The only extensive anomalies were filler bar scorching and over-predictions in the high Delta p gap heating regions of the orbiter. A technique to predict filler bar scorching has been developed that can aid in defining a solution. Improvement in high Delta p gap heating methodology is still under study. Minor anomalies were also examined for improvements in modeling techniques and prediction capabilities. These include improved definition of low Delta p gap heating, an analytical model for inner mode line convection heat transfer, better modeling of structure, and inclusion of sneak heating. The limited number of problems related to penetration items that presented themselves during orbital flight tests were resolved expeditiously, and designs were changed and proved successful within the time frame of that program

On Multivariate Power Series of Random Variables Satisfying Some Hierarchy Conditions

Let {X n } n≥1 be a sequence of i.i.d. random vectors such that the distribution of X n is uniquely determined by its moments. We show that for a multivariate power series in the components of {X n } n≥1 that satisfies some algebraic "hierarchy condition” with respect to the vector components, whose coefficients fulfill a suitable positivity property, and which is absolutely L p -convergent for all p ≥ 1, the distribution of the series determines uniquely the distribution of X n . In statistical language, this means that the distribution (if it can be observed, e.g., by sampling from several i.i.d. models) of the power series under consideration is a sufficient statistic for the distribution of X n . Special cases are generalized ARMA models where the dependence structure is not necessarily linear. This applies, e.g., to stock price models with random volatility and to mechanics (kinetic energy). The assertion can also be generalized to the case where the coefficients of the power series form a stochastic process that is independent of {X n } n≥1

Uniqueness of Embedding into a Gaussian Semigroup and a Poisson Semigroup with Determinate Jump Law on a Simply Connected Nilpotent Lie Group

Let {mu((i))(t)}(t >= 0) (i=1,2) be continuous convolution semigroups (c.c.s.) on a simply connected nilpotent Lie group G. Suppose that mu((1))(1)=mu((2))(1). Assume furthermore that one of the following two conditions holds: (i) The c.c.s. {mu((1))(t)}(t >= 0) is a Gaussian semigroup (in the sense that its generating distribution just consists of a primitive distribution and a second-order differential operator) (ii) The c.c.s. {mu((i))(t)}(t >= 0) (i=1,2) are both Poisson semigroups, and the jump measure of {mu((1))(t)}(t >= 0) is determinate (i.e., it possesses all absolute moments, and there is no other nonnegative bounded measure with the same moments). Then mu((1))(t) = mu((2))(t) for all t >= 0. As a complement, we show how our approach can be directly used to give an independent proof of Pap's result on the uniqueness of the embedding Gaussian semigroup on simply connected nilpotent Lie groups. In this sense, our proof for the uniqueness of the embedding semigroup among all c.c.s. of a Gaussian measure can be formulated self-contained

Long-term conservation and rehabilitation of threatened rain forest patches under different human population pressures in West Africa

The management schemes of four rain forest patches in southern Benin and south-western Nigeria, which led to the successful protection of numerous threatened plants and animals over the last 20 plus years, are analysed. Since climatic conditions are similar, tree composition depends largely on different availability of water and documented biodiversity mostly on the availability of taxonomic expertise. Management differs according to accessibility and human population pressure, from total closing off of the forest by an international institute near the mega-polis Ibadan to unmarked borders near Lanzron, a remote village in the lower Ouémé Valley, where foreigners are mostly excluded from visiting the site. In Benin, trees and wildlife (antelopes and monkeys) seem best protected where the local vodoun beliefs are adhered to. This is, however, not sufficient and development aid to support and benefit the local population is needed as exemplified in Zinvié. At the Ibadan and Drabo sites, long-term protection is assured by legally-binding land-titles. Since for all of Lanzron and part of Zinvié these are lacking securing them is a priority. In Ibadan, Nigeria, a major rehabilitation effort is concentrated on bringing relatively old grass land and former village sites under forest cover by planting local trees. Rehabilitation in Drabo, in southern Benin, relies on enriching the naturally occurring fallow succession with rare species from nearby threatened sacred forests. We demonstrate that reversing biodiversity loss is possible but requires a long-term commitment. Recommendations for protecting, stabilizing and enhancing similar small hotspots of biodiversity are made

On Chung's Law of Large Numbers on Simply Connected Step 2-Nilpotent Lie Groups

Ordóñez Cabrera and Sung (2002) have proved that under certain "moment” conditions, for triangular arrays of weighted Banach-valued random variables, a.s. convergence, convergence in L 1, convergence in probability, and complete convergence to 0 are equivalent, thus giving a variant of Chung's law of large numbers. We extend their result (under slightly sharper technical conditions) to symmetric random variables on simply connected step 2-nilpotent Lie groups

A new Proof for the Lévy Construction of Second Kind for Stable Laws

We give a direct proof for the "Lévy construction of second kind” for stable laws on the real line without referring to the construction of "first kind.

Class reconstruction driven adversarial domain adaptation for hyperspectral image classification

We address the problem of cross-domain classification of hyperspectral image (HSI) pairs under the notion of unsupervised domain adaptation (UDA). The UDA problem aims at classifying the test samples of a target domain by exploiting the labeled training samples from a related but different source domain. In this respect, the use of adversarial training driven domain classifiers is popular which seeks to learn a shared feature space for both the domains. However, such a formalism apparently fails to ensure the (i) discriminativeness, and (ii) non-redundancy of the learned space. In general, the feature space learned by domain classifier does not convey any meaningful insight regarding the data. On the other hand, we are interested in constraining the space which is deemed to be simultaneously discriminative and reconstructive at the class-scale. In particular, the reconstructive constraint enables the learning of category-specific meaningful feature abstractions and UDA in such a latent space is expected to better associate the domains. On the other hand, we consider an orthogonality constraint to ensure non-redundancy of the learned space. Experimental results obtained on benchmark HSI datasets (Botswana and Pavia) confirm the efficacy of the proposal approach

Uniqueness of the embedding continuous convolution semigroup of a Gaussian probability measure on the affine group and an application in mathematical finance

Let {mu((i))(t)}(t >= 0) (i = 1, 2) be continuous convolution semigroups (c.c.s.) of probability measures on Aff(1) (the affine group on the real line). Suppose that mu((1))(1) = mu((2))(1). Assume furthermore that {mu((1))(t)}(t >= 0) is a Gaussian c.c.s. (in the sense that its generating distribution is a sum of a primitive distribution and a second-order differential operator). Then mu((1))(1) = mu((2))(1) for all t >= 0. We end up with a possible application in mathematical finance

Invasive floating water weeds – killing life and commerce

Weeds by definition are plants that grow in the wrong place. When their seeds or other plant parts are transported to other regions where their natural enemies are absent, they can multiply unhindered. Indigenous plants, especially those that are adapted for invading disturbed areas, can also become weeds. The first category is a particularly good target for classical biological control. Insects, mites and micro-organisms that feed on them are imported from their original area and released against the new invader. Against indigenous plants however, biological control is far less promising. By the end of 1980s, many of the water bodies in West Africa were invaded by alien plant species considered to be among the world’s worst aquatic weeds: water hyacinth Eichhornia crassipes, water lettuce Pistia stratiotes, and water fern Salvinia molesta. They were accidentally or deliberately introduced as ornamentals or for use in aquariums from their native range South America to many parts of the world where they have become invasive

Thoracic Gas Volume in Athletes and Non-Athletes

The purpose of this study was to analyze the predicted thoracic gas volume versus measured thoracic gas volume in college students, comparing NCAA collegiate athletes versus non-athletes using the Bod Pod. Forty-four college students, both males and females, athletes and non-athletes, completed a body composition test to obtain the predicted thoracic gas volume. The participants were then instructed by the Bod Pod software through the measured thoracic gas volume test. Due to low statistical power, athletes and non-athletes were unable to be compared, however, results of a two sample t-test showed that there was a statistically significant difference between measured thoracic gas volume and predicted thoracic gas volume within the population as a whole. The average predicted thoracic gas volume was 3.66 liters ± 0.103 while the measured thoracic gas volume was 4.02 liters ± 0.165. The significance level for the test was p ≤ 0.05 and the p-value obtained from the statistical analysis was p ≤ 0.001. It was concluded that within this study, there was a significant difference between the predicted and measured thoracic gas volumes of the population