A means for utilizing ancillary information in multispectral classification

A method is presented that allows information from ancillary data sources to be incorporated into the results of an existing classification of remotely sensed data. Based upon probabilistic label relaxation procedures, which are used for imbedding spatial context data in image-labeling problems, the method utilizes the source of ancillary information in the form of a set of probabilities. These are injected into a modified relaxation method called supervised relaxation labeling which, on application, develops a labeling for remotely sensed data that strikes a balance in consistency between spectral, spatial, and ancillary data sources of information. Results are presented of a forestry classification in which accuracy is improved from 68% to 81% by incorporating topographic elevation in the manner outlined.     

Calculation of the Transient Response of Long Chains of Slightly Lossy Coupled Resonators

Methods of calculating and of illustrating the transient response of chains of coupled resonators are discussed. Such calculations are particularly useful in understanding the rf field behavior in linear accelerator structures, both of the drift tube and waveguide or coupled cavity types. Resonator chains are also employed in certain kinds of filters and delay lines; the methods to be discussed are applicable in these areas, as well. A frequency adjustment is presented which permits difference equations with a large time step to accurately represent the differential equations for slightly lossy coupled resonators.     

Hydroxyapatite-coated metals: Interfacial reactions during sintering

Electrophoretic deposition (EPD) is a low cost flexible process for producing HA coatings on metal implants. Its main limitation is that it requires heating the coated implant in order to densify the HA. HA typically sinters at a temperature below 1150C, but metal implants are degraded above 1000C. Further, the metal induces the decomposition of the HA coating upon sintering. Recent developments have enabled EPD of metathesis-synthesised uncalcined HA which sinters at 1000C. The effects of temperature on HA-coated Ti, Ti6Al4V, and 316L stainless steel were investigated for dual coatings of metathesis HA sintered at 1000C. The use of dual HA coatings (coat, sinter, coat, sinter) enabled decomposition to be confined to the undercoat (HA layer 1), with the surface coating decomposition free. The tensile strength of the three metals was not significantly affected by the high sintering temperatures (925C < T < 1000C). XRD/SEM/EDS analyses of the interfacial zones revealed that 316L had a negligible HA:metal interfacial zone (1 m) while HA:Ti and HA:Ti6Al4V had large interfacial zones (>10 m) comprising a TiO₂ oxidation zone and a CaTiO₃ reaction zone.     

Computational modeling of heat transfer in magneto-non-Newtonian material in a circular tube with viscous and Joule heating

Numerous industrial and engineering systems, like, heat exchangers, chemical action reactors, geothermic systems, geological setups, and many others, involve convective heat transfer through a porous medium. The diffusion rate, drag force, and mechanical phenomenon are dealt with in the Darcy–Forchheimer model, and hence this model is vital to study the fluid flow and heat transport analysis. Therefore, numerical simulation of the Darcy–Forchheimer dynamics of a Casson material in a circular tube subjected to the energy losses due to the viscous heating and Joule dissipation mechanisms is performed. The novelty of the present investigation is to scrutinize the convective heat transport characteristics in a circular tube saturated with Darcy–Forchheimer porous matrix by utilizing the non-Newtonian Casson fluid. The flow occurs due to the elongation of the surface of a tube with a uniform heat-based source/sink. The similarity solution of the nonlinear problem was obtained using dimensionless similarity variables. The effects of operating parameters related to the flow phenomena are analyzed. Further, the friction factor and Nusselt number are also analyzed in detail. The present flow model ensures no flow reversal and acts as a coolant of the heated cylindrical surface; the existence of the magnetic field, as well as an inertial coefficient, acts as the momentum-breaking forces, whereas Casson fluidity builds it. The Joule heating phenomenon enhances the magnitude of temperature. The thermal field of the Casson fluid is higher at the surface of the circular pipe due to convective thermal conditions.     

Temporal Variation of Energy Fluxes During Dry Season in Tropical Lowland Rice

Temporal variation of ‘surface energy balance’ was quantified on tropical lowland rice for 4 years (2013–2016). High response (10 Hz) eddy covariance system was used to estimate real time data on net radiation (NR), sensible heat (Hs), latent heat (LE), air and soil temperature. Annual, monthly, diurnal as well as phenological crop stage wise variation were analysed. Majority of radiation received from sun was partitioned into latent heat (LE, 44–73%) followed by soil heat (G, 13–42%) and sensible heat (Hs 3–16%) in dry cropping season. This was primarily due to presence of stagnant water in this ecology throughout the cropping period except few days during harvesting. Average Hs was negative in the month of April because of higher evapotranspiration during full grown crop at its reproductive stage as well as stagnant water in field. LE was the major contributor of energy balance and consistently increased from active tillering to grain filling stages then gradually decreased in harvesting. Hs contributing more at the initial stages of rice. Diurnal variation showed maximum Hs during 12:00 to 13:00 hours, whereas, highest LE and G were noticed during 13:00 and 11:30–12:00 hours, respectively. LE and G regressed well than Hs with air temperature and NR.     

Green synthesis of copper sulfide (CuS) nanostructures for heterojunction diode applications

Copper sulfide (CuS) rod shaped nanostructures with an average length 8 to 10 nm are synthesized through green chemical route using biodegradable starch as a capping agent under a nitrogen environment. Owing to the presence of a large number of glucose units linked by glycosidic bonds, starch can cap copper sulfide (CuS) nanoparticles. The preparation of CuS under nitrogen atmosphere produces fine quality CuS nanostructures by minimizing oxidation. XRD pattern reveals pure hexagonal covellite type CuS nanostructure with prime diffraction planes along (101), (102), (103), (006), (008), and (110) directions. The lattice parameters estimated as a?=?3.790 Å and c?=?16.51 Å. HRTEM studies show a well distribution of CuS nanorods. It shows prominent d-value of 0.28 nm corresponding to (103) hexagonal plane of CuS. The optical absorption extended up to 364 nm which is fairly blue shifted over bulk owing to the quantum confinement brought by starch. The photoluminescence emission is observed at 525 nm. The I–V measurements in planar geometry exhibit the linearity that reveals the ohmic behavior of carrier transport in CuS nanostructures. CuS nanostructures have been successfully used as effective p-type layer to fabricate sandwiched heterojunction devices with zinc chalcogenides (ZnO/ZnS and ZnS/ZnO) core/shell nanocomposites. The p-CuS/n-(zinc chalcogenides) heterojunction devices show good diode characteristics with an increase of ideality factor that may be attributed to surface defects and inhomogeneity in the barrier height. The photodetector also exhibits promising characteristics in terms of responsivity and quantum efficiency which are significant corresponding to material properties.