Space fabrication: Graphite composite truss welding and cap forming subsystems

An automated beam builder for the fabrication of space structures is described. The beam builder forms a triangular truss 1.3 meters on a side. Flat strips of preconsolidated graphite fiber fabric in a polysulfone matrix are coiled in a storage canister. Heaters raise the material to forming temperature then the structural cap section is formed by a series of rollers. After cooling, cross members and diagonal tension cords are ultrasonically welded in place to complete the truss. The stability of fabricated structures and composite materials is also examined

An analytical investigation of NO sub x control techniques for methanol fueled spark ignition engines

A thermokinetic SI engine simulation was used to study the effects of simple nitrogen oxide control techniques on performance and emissions of a methanol fueled engine. As part of this simulation, a ring crevice storage model was formulated to predict UBF emissions. The study included spark retard, two methods of compression ratio increase and EGR. The study concludes that use of EGR in high turbulence, high compression engines will both maximize power and thermal efficiency while minimizing harmful exhaust pollutants

Nonparametric methods for the characteristic model

Characteristics models have been found to be useful in many areas of economics. However, their empirical implementation tends to rely heavily on functional form assumptions. In this paper we develop a revealed preference-based nonparametric approach to characteristics models. We derive the minimal necessary and sufficient empirical conditions under which data on the market behaviour of individual, heterogeneous, pricetaking consumers are nonparametrically consistent with the consumer characteristics model. Where these conditions hold, we show how information may be recovered on individual consumer’s marginal valuations of product attributes. In some cases marginal valuations are point identified and in other cases we can only recover bounds. Where the conditions fail we highlight the role which the introduction of unobserved product attributes can play in rationalising the data. We implement these ideas using consumer panel data on the Danish milk market

Current viewpoints on oxide adherence mechanisms

Additional hot stage Auger experiments have provided surface segregation data for NiCrAl + or - Y or Zr alloys in agreement with other investigations. This data, combined with experimental and theoretical evidence of the Al2O3-metal bond strength, is presented in support of a chemical mechanism of Al2O3 scale adhesion. Both the detrimental effects of sulfur segregation and the beneficial effects of dopant segregation may be important. Chemical features of the dopants are compared in light of these proposed mechanisms, namely delta H sub f (sulfide), delta H sub f (oxide), electron orbital configuration, and insolubility in Ni

ALTERNATIVE METHODS OF ACCOUNTING FOR LIVESTOCK CAPITAL FORMATION: AN APPLICATION TO SOUTHERN U.S. AGRICULTURE

Livestock Production/Industries,

Detecting Identity by Descent and Estimating Genotype Error Rates in Sequence Data

Existing methods for identity by descent (IBD) segment detection were designed for SNP array data, not sequence data. Sequence data have a much higher density of genetic variants and a different allele frequency distribution, and can have higher genotype error rates. Consequently, best practices for IBD detection in SNP array data do not necessarily carry over to sequence data. We present a method, IBDseq, for detecting IBD segments in sequence data and a method, SEQERR, for estimating genotype error rates at low-frequency variants by using detected IBD. The IBDseq method estimates probabilities of genotypes observed with error for each pair of individuals under IBD and non-IBD models. The ratio of estimated probabilities under the two models gives a LOD score for IBD. We evaluate several IBD detection methods that are fast enough for application to sequence data (IBDseq, Beagle Refined IBD, PLINK, and GERMLINE) under multiple parameter settings, and we show that IBDseq achieves high power and accuracy for IBD detection in sequence data. The SEQERR method estimates genotype error rates by comparing observed and expected rates of pairs of homozygote and heterozygote genotypes at low-frequency variants in IBD segments. We demonstrate the accuracy of SEQERR in simulated data, and we apply the method to estimate genotype error rates in sequence data from the UK10K and 1000 Genomes projects

Averages of shifted convolutions of d3(n)d_3(n)

We investigate the first and second moments of shifted convolutions of the generalised divisor function $d_3(n)$.Comment: 22 page

Comparison of Productivity of Different Breeds of Meat Goats Under Low-to-Moderate-Input Systems in the United States

Abstract Boer and Kiko goats were imported in the 1990s to enhance the productivity of the US base population of Spanish meat goats. Successful breed introductions require adaptation to the destination environment. Well-planned, low-input management is a good route to meat goat enterprise profitability using proper goat genetics. Reproduction drives profit more than growth and carcass traits. Results of breed evaluation studies on doe reproductive and health traits, the Boer goat influence tended to be negative compared with Kiko and Spanish goat influences. Reduced doe herd reproductive output suggests reduced enterprise profitability. Differences in growth or carcass traits among sire breeds have not consistently favored any particular breed. Boer goat genetics improved visual conformation, which increases market value. Improved visual appraisal has not translated into enhancements for objectively measured carcass traits. Proper breed selection and use in meat goat mating systems are important for enhanced doe herd productivity and profitability in low-input, limited-resource operations. Keywords: Productivity, Breeds, Meat Goat Breeds, Input System

Cognitive and emotional variables in childhood anxiety

Research was conducted on 60 subjects from mental health agencies in order to determine that childhood anxiety and depression can be differentiated. The 60 subjects were given the CDI and the RCMAS self-report measures in order to be placed in groups. This allowed the subjects to be divided into 4 groups: Anxious, Anxious/Depressed, Depressed and Not Anxious/Not Depressed. The 4 groups were then given 2 additional self-report measures, the STAIC and FSSC -R to measure whether Anxious and the Anxious/Depressed children exhibited more fears and anxious traits than did the Depressed and Not Anxious/Not Depressed children. Analyses of variance revealed that the Anxious and Anxious/Depressed subjects were significantly different from the Depressed and Not Anxious/Not Depressed subjects. Anxiety is closely related to the cognitive and emotional component of fear. The study was successful in demonstrating significant differences of cognitions and feelings experienced by depressed and anxious children