Heat transfer in unsteady MHD couette flow of an electrically conducting,viscous, incompressible rarefied gas

An analytical study is performed to examine the heat transfer characteristics on the flow of a viscous, incompressible rarefied gas in a parallel plate channel under the action of transverse magnetic field when (i) suction velocity normal to the plate is constant, (ii) the second plate oscillates in time about a constant non-zero mean, (iii) fluid is subjected to a constant heat source of absorption type. Apprximate solutions for velocity, temperature, phase, and amplitude of skin-friction and rate of heat transfer are evaluated. Mean temperature profiles, phase and amplitude of rate of heat transfer at both plates are discussed graphically followed by a quantitative discussion. Mean rate of heat transfer is tabulated in Table I.     

Diffusion of rare gases of solar wind origin from lunar fines as bubbles

A diffusion mechanism is proposed which takes into account phenomena observed in ion-implanted solids, in particular the precipitation of rare gas in the form of bubbles and their migration. The composition of rare gases in the bubbles is inferred from the calculated distribution of solar wind rare gas ions as a function of depth in the grains. These calculations are made for the location and average composition of Apollo 11 samples. It is shown by analogy with experimental observations in ion-implanted solids that the bubbles would migrate towards the surface and that the diffusion constant for this migration would be strongly depth dependent. Relative abundances of rare gas nuclides remaining behind due to the resultant degassing are estimated for one Apollo 11 soil sample and are compared with observed relative abundances for this sample. A qualitative explanation of some of the experimental observations of Ducati et al. on individual lunar grains is also offered.     

Cogeneticity of Tavidar volcanics: Evidence by mixing line calculation

The Tavidar volcanics belong to a trachybasalt-trachyandesite-rhyolite association. Distribution and behavior of major and trace elements and field relationships indicate that intermediate and acidic volcanics of the area are cogenetic, whereas the basaltic phase is younger. Cogeneticity also is confirmed by the mixing line calculation. In the present case, instead of two pole mixing, three pole mixing between end members andesite, quartztrachyte, and rhyolite has been considered. Results show that a perfect linearity in data exists between andesites and quartztrachyte and between quartztrachyte and rhyolites.     

Extraction and validation of cartosat-1 DEM

CARTOSAT-1 satellite, launched in May, 2005 is a dedicated along track stereo mission providing high quality data for topographic and cartographic applications. The present paper describes the evaluation of the Cartosat-1 stereo data, mainly through the generation and validation of DEM for moderately undulating and hilly areas. Photogrammetric techniques have been used for generation of DEM and Orthoimage for two cases i.e. 1) using RPCs (Rational Polynomial Coefficients) and 2) using RPCs along with ground control points. Root Mean Square Error (RMSE) in elevation values for the moderately undulating (Dehradun) and hilly area (Shimla), are found to be 4.38 and 3.69m respectively.     

A genetic model of thrust-bounded intermontane basin using scaled sandbox analogue models: an example from the Karewa Basin, Kashmir Himalayas, India

The Himalayan mountain system has many depressions of regional dimensions, which are found oriented mostly E–W to NE–SW, mainly to the north of the main boundary fault (MBF). The Karewa Basin in the Kashmir Himalaya has sediments belonging to late Neogene to Quaternary formations, which represent an almost 1,300-m-thick succession of sand, mud and gravels exposed in the river valleys and the plateau margins of the entire Kashmir Valley. Sandbox analogue experiments show a great variety of wedge shapes showing significant changes in the taper angles due to the change in basal friction. Between two pop-ups or depressions (pop-down) of significant dimensions develop along the strike of the growing wedge. In order to maintain the critical angle, these depressions initially receive material from the hinterland, and later on, from the foreland end of the wedge. The depressions have developed due to the change in the surface slope of the wedge, and receive the eroded material only from the adjacent upheaved portions of the wedge. On continuation of the experiments (in cases where the wedge is highly unstable), these depressions are coupled with the wedge along with their sand-fills. The depositional history of the Karewa sediments indicates a sequential evolutionary pattern of the basin and thus represents a natural analogue of the sandbox experiments.     

A Platform for Visualizing and Experimenting with Measures of Semantic Similarity in Ontologies and Concept Maps

This article describes research in the ongoing search for better semantic similarity tools: such methods are important when attempting to reconcile or integrate knowledge, or knowledge‐related resources such as ontologies and database schemas. We describe an extensible, open platform for experimenting with different measures of similarity for ontologies and concept maps. The platform is based around three different types of similarity, that we ground in cognitive principles and provide a taxonomy and structure by which new similarity methods can be integrated and used. The platform supports a variety of specific similarity methods, to which researchers can add others of their own. It also provides flexible ways to combine the results from multiple methods, and some graphic tools for visualizing and communicating multi‐part similarity scores. Details of the system, which forms part of the ConceptVista open codebase, are described, along with associated details of the interfaces by which users can add new methods, choose which methods are used and select how multiple similarity scores are aggregated. We offer this as a community resource, since many similarity methods have been proposed but there is still much confusion about which one(s) might work well for different geographical problems; hence a test environment that all can access and extend would seem to be of practical use. We also provide some examples of the platform in use.     

Lithospheric structure beneath Laxmi Ridge and late Cretaceous geodynamic events

The geophysically unusual Laxmi Ridge (eastern basin, Arabian Sea) is associated with a prominent elongated negative gravity anomaly. A seismically and geodynamically constrained detailed 2D gravity modeling suggests an 11-km-thick normal oceanic crust and an asthenospheric upwarp to a depth of 35 km. We attribute the apparent thickening of the crust to a possible emplacement of an anomalous subcrustal low-density layer between 11 and 19 km depth. We hypothesize that a K-T boundary bolide impact near the Bombay offshore led to several geological events, including eruption of Deccan flood basalts. The spreading Carlsberg Ridge in the Indian Ocean and rifting associated with Deccan volcanism generated the compressive regime, which perhaps originated the Laxmi Ridge.     

A rapid method of trace analysis of uranium(VI) from phosphorites

A new spectrophotometric method for the microdetermination of uranium(VI) from phosphorites in the presence of commonly occurring metal ions has been developed. Uranium is extracted from chloroform solution of N-phenyl-2-naphtho-hydroxamic acid (N-P-2-NHA) at pH 4.0–4.5. The orange-red extract has the maximum absorption at 515 nm. The extraction was quantitative and obeys Beer's law at 515 nm.     

The Neogene/Quaternary boundary in India: A review

The Neogene/Quaternary boundary has been variously defined in different continents. A global review of the problem shows that only the Olduvai event on the palaeomagnetic timescale may provide an universally acceptable isochronous datum for delineating this boundary. The N/Q boundary in the Siwaliks, Kashmir and the Andamans in India is defined in the light of recent research.