Conceptual design, evaluation and research identification for Remote Augmented Propulsive Lift Systems (RALS) with ejectors for VTOL aircraft

Ejector concepts for use with a remote augmented lift system (RALS) exhaust nozzle were studied. A number of concepts were considered and three were selected as having the greatest promise of providing the desired aircraft and exhaust gas cooling and lift enhancement. A scale model test program is recommended to explore the effects of the more important parameters on ejector performance

Genomic regions associated with common root rot resistance in the barley variety Delta

Common root rot (CRR) caused by Bipolaris sorokiniana is a serious disease constraint in the dry temperate cereal growing regions of the world. Currently little is known about the genetic control of resistance to CRR in cereals. In this study based on a Delta/Lindwall barley population we have undertaken a bulked segregant analysis (BSA) and whole genome mapping approach utilising Diversity Arrays Technology (DArT) to identified quantitative trait loci (QTL) associated with CRR expression. One QTL each was identified on chromosomes 4HL and 5HL explaining 12 and 11% of the phenotypic variance, respectively

Atlas 5013 tank corrosion test

The type and cause of corrosion in spot welded joints were determined by X-ray and chemical analysis. Fatigue and static tests showed the degree of degradation of mechanical properties. The corrosion inhibiting effectiveness of WD-40 compound and required renewal period by exposing typical joint specimens were examined

Factors affecting the retention of knowledge workers.

One of the characteristics of knowledge workers is their high level of mobility. The cost of labour turnover of these key resources is high in both financial and non financial terms. There is thus a need to understand what the factors are that underpin the retention cognitions of knowledge workers. Data was collected from 306 knowledge workers in full time employment representing a wide range of demographic groupings. The results showed that job satisfaction and organisational commitment do not predict knowledge workers’ proposed future length of service. Factor analysis revealed seven underlying dimensions of retention cognitions. Cluster analysis revealed nine distinct clusters of knowledge workers with regard to their retention cognitions. High levels of individualism, need for challenge and focus on personal development were demonstrated. The implications of these findings are discussed

Conservation laws in the continuum 1/r21/r^2 systems

We study the conservation laws of both the classical and the quantum mechanical continuum $1/r^2$ type systems. For the classical case, we introduce new integrals of motion along the recent ideas of Shastry and Sutherland (SS), supplementing the usual integrals of motion constructed much earlier by Moser. We show by explicit construction that one set of integrals can be related algebraically to the other. The difference of these two sets of integrals then gives rise to yet another complete set of integrals of motion. For the quantum case, we first need to resum the integrals proposed by Calogero, Marchioro and Ragnisco. We give a diagrammatic construction scheme for these new integrals, which are the quantum analogues of the classical traces. Again we show that there is a relationship between these new integrals and the quantum integrals of SS by explicit construction.Comment: 19 RevTeX 3.0 pages with 2 PS-figures include

Fusarium pseudograminearum crown rot: growth patterns in planta

Crown rot (causal agent Fusarium pseudograminearum) is a major constraint on wheat production in Australia and globally. While discolouration of tissues is commonly used to screen for resistance, the degree to which the pathogen colonises the full range of seedling and adult host tissues is an important aspect of the disease process. After coleoptile inoculation, seedlings were examined using quantitative PCR to determine the spread of F. pseudograminearum into different host tissues during crown rot pathogenesis at 14 and 28 days after inoculation. Quantitative PCR and visual assessment indicated that while most seedling tissues (leaf sheath, leaf blade, sub-crown internode, primary root and secondary root) were colonised, the basal portion of leaf sheath tissue supported the highest density of F. pseudograminearum. Microscopic assessment demonstrated the growth of hyphae predominantly in the parenchyma cells, with passage into and out of seedling shoot tissues being predominantly via stomata. Assessment of colonised stem tissues in inoculated field trials of adult plants at 16 and 22 weeks after planting indicate a strong correlation between visual discolouration and fungal biomass, with the discolouration occurring in the parenchymatous hypoderm. Hyphae spread from the culm base vertically through the tissues, initially via the hypoderm and the central pith cavity. Colonisation of sclerified cells occurs later in the disease process. Both xylem and phloem tissues became colonised by 16 weeks after planting in all host genotypes tested. Nodal tissues do not appear to constitute any major impediment to the spread of fungal infection. The observation of F. pseudograminearum colonisation of vascular tissues is consistent with the hypothesis of compromised vascular flow of either or both of the xylem and phloem pathways during crown rot disease

High time resolution observation of the transient event of 5 March 1979

The detection of an intense gamma ray burst with the monitor proportional counter on the HEAO 2 spacecraft is discussed with particular emphasis on the measurement of the time of onset of the event. Based on the mean observed counting rate in the burst and assuming a sharp rise, the uncertainty in the burst onset is found to be + or - 220 microseconds. The time of occurrence was 57124.826908 + or - 0.000220 s UT on March 5, 1979, and the location of the HEAO 2 satellite at this time was latitude 22.15 deg, longitude -27.60 deg at an altitude of 525.0 km

Solutions to the Multi-Component 1/R Hubbard Model

In this work we introduce one dimensional multi-component Hubbard model of 1/r hopping and U on-site energy. The wavefunctions, the spectrum and the thermodynamics are studied for this model in the strong interaction limit $U=\infty$. In this limit, the system is a special example of $SU(N)$ Luttinger liquids, exhibiting spin-charge separation in the full Hilbert space. Speculations on the physical properties of the model at finite on-site energy are also discussed.Comment: 9 pages, revtex, Princeton-May1

The Effects of Fish Trap Mesh Size on Reef Fish Catch off Southeastern Florida

Catch and mesh selectivity of wire-meshed fish traps were tested for eleven different mesh sizes ranging from 13 X 13 mm (0.5 x 0.5") to 76 x 152 mm (3 X 6"). A total of 1,810 fish (757 kg) representing 85 species and 28 families were captured during 330 trap hauls off southeastern Florida from December 1986 to July 1988. Mesh size significantly affected catches. The 1.5" hexagonal mesh caught the most fish by number, weight, and value. Catches tended to decline as meshes got smaller or larger. Individual fish size increased with larger meshes. Laboratory mesh retention experiments showed relationships between mesh shape and size and individual retention for snapper (Lutjanidae), grouper (Serranidae), jack (Carangidae), porgy (Sparidae), and surgeonfish (Acanthuridae). These relationships may be used to predict the effect of mesh sizes on catch rates. Because mesh size and shape greatly influenced catchability, regulating mesh size may provide a useful basis for managing the commercial trap fishery