Thrust chamber performance using Navier-Stokes solution

The viscous, axisymmetric flow in the thrust chamber of the space shuttle main engine (SSME) was computed on the CRAY 205 computer using the general interpolants method (GIM) code. Results show that the Navier-Stokes codes can be used for these flows to study trends and viscous effects as well as determine flow patterns; but further research and development is needed before they can be used as production tools for nozzle performance calculations. The GIM formulation, numerical scheme, and computer code are described. The actual SSME nozzle computation showing grid points, flow contours, and flow parameter plots is discussed. The computer system and run times/costs are detailed

Electronic structure Fermi liquid theory of high T(sub c) superconductors: Comparison with experiments

For years, there has been controversy on whether the normal state of the Cu-oxide superconductors is a Fermi liquid or some other exotic ground state. However, some experimentalists are clarifying the nature of the normal state of the high T(sub c) superconductors by surmounting the experimental difficulties in producing clean, well characterized surfaces so as to obtain meaningful high resolved photoemission data, which agrees with earlier positron-annihilation experiments. The experimental work on high resolution angle resolved photoemission by Campuzano et al. and positron-annihilation studies by Smedskjaer et al. has verified the calculated Fermi surfaces in YBa2Cu3O7 superconductors and has provided evidence for the validity of the energy band approach. Similar good agreement was found for Bi2Sr2CaCu2O8 by Olson et al. As a Fermi liquid (metallic) nature of the normal state of the high T(sub c) superconductors becomes evident, these experimental observations have served to confirm the predictions of the local density functional calculations and hence the energy band approach as a valid natural starting point for further studies of their superconductivity

Electronic structure Fermi liquid theory of high Tc superconductors: Comparison of predictions with experiments

Predictions of local density functional (LDF) calculations of the electronic structure and transport properties of high T(sub c) superconductors are presented. As evidenced by the excellent agreement with both photoemission and positron annihilation experiments, a Fermi liquid nature of the 'normal' state of the high T(sub c) superconductors become clear for the metallic phase of these oxides. In addition, LDF predictions on the normal state transport properties are qualitatively in agreement with experiments on single crystals. It is emphasized that the signs of the Hall coefficients for the high T(sub c) superconductors are not consistent with the types of dopants (e.g., electron-doped or hole-doped) but are determined by the topology of the Fermi surfaces obtained from the LDF calculations

Mind-reading versus neuromarketing: how does a product make an impact on the consumer?

Purpose – This research study aims to illustrate the mapping of each consumer’s mental processes in a market-relevant context. This paper shows how such maps deliver operational insights that cannot be gained by physical methods such as brain imaging. Design/methodology/approach – A marketed conceptual attribute and a sensed material characteristic of a popular product were varied across presentations in a common use. The relative acceptability of each proposition was rated together with analytical descriptors. The mental interaction that determined each consumer’s preferences was calculated from the individual’s performance at discriminating each viewed sample from a personal norm. These personal cognitive characteristics were aggregated into maps of demand in the market for subpanels who bought these for the senses or for the attribute. Findings – Each of 18 hypothesized mental processes dominated acceptance in at least a few individuals among both sensory and conceptual purchasers. Consumers using their own descriptive vocabulary processed the factors in appeal of the product more centrally. The sensory and conceptual factors tested were most often processed separately, but a minority of consumers treated them as identical. The personal ideal points used in the integration of information showed that consumers wished for extremes of the marketed concept that are technologically challenging or even impossible. None of this evidence could be obtained from brain imaging, casting in question its usefulness in marketing. Research limitations/implications – Panel mapping of multiple discriminations from a personal norm fills three major gaps in consumer marketing research. First, preference scores are related to major influences on choices and their cognitive interactions in the mind. Second, the calculations are completed on the individual’s data and the cognitive parameters of each consumer’s behavior are aggregated – never the raw scores. Third, discrimination scaling puts marketed symbolic attributes and sensed material characteristics on the same footing, hence measuring their causal interactions for the first time. Practical implications – Neuromarketing is an unworkable proposition because brain imaging does not distinguish qualitative differences in behavior. Preference tests are operationally effective when designed and analyzed to relate behavioral scores to major influences from market concepts and sensory qualities in interaction. The particular interactions measured in the reported study relate to the major market for healthy eating. Originality/value – This is the first study to measure mental interactions among determinants of preference, as well as including both a marketed concept and a sensed characteristic. Such an approach could be of great value to consumer marketing, both defensively and creatively

Device measures fluid drag on test vehicles

Electromechanical drag balance device measures the aerodynamic drag force acting on a vehicle as it moves through the atmosphere and telemeters the data to a remote receiving station. This device is also used for testing the hydrodynamic drag characteristics of underwater vehicles

Large anisotropy in the optical conductivity of YNi2B2C

The optical properties of YNi$_2$B$_2$C are studied by using the first-principles full-potential linearized augmented plane wave (FLAPW) method within the local density approximation. Anisotropic behavior is obtained in the optical conductivity, even though the electronic structure shows 3D character. A large peak in $\sigma_z$ is obtained at 2.4 eV. The anisotropic optical properties are analyzed in terms of interband transitions between energy levels and found that the Ni site plays an important role. The electronic energy loss spectroscopy (EELS) spectra are also calculated to help elucidate the anisotropic properties in this system.Comment: revtex4, 4 pages, 5 figures, to appear in PR