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We report on the Chip-on-Plate (COP) packaged high power LED assemblies for solid state lighting (SSL) and backlighting display applications from thermal analysis perspective. Three different light modules with different elements (devices) distribution and heatsink design were considered. Thermal resistance circuit (TRC) model and heat diffusion equation were employed in this study of thermal behavior of the assembly elements. Finite element analysis along with 3D modeling and simulations were used for considered lighting modules and assemblies. Also, the effect of thermal uniformity on the emission spectra was evaluated for different operating powers. Comparative study showed that conventional packages with circularly symmetric having non-uniform devices’ distribution per unit area will have temperature differences ∼7 °C among the chip-elements operating around 1.25 W power level. Also, it was predicted that high elements temperature difference could result in over 2 nm redshift in the emission spectra accompanied by ∼ 4% drop in the output power. However, temperature difference was found to be less than 1 °C for the uniform rectangular array module distribution, which ensures uniform output intensity for all devices. Such findings are extremely useful for designing larger area LED packaging where thermal non-uniformity effects are expected to be more severe for devices’ longevity and performance. [ABSTRACT FROM AUTHOR]

• To enhance the AC conductivity of synthesized β-SVO/aniline nanocomposites. • A hydrothermal approach is used to synthesize the β phase of SVO nanowires. • Different loadings 50 wt%, 60 wt% and 70 wt% of aniline to β-SVO nanowires. • Significant role of magnetic stirring is observed in adsorption of aniline. • Improved AC conductivity with 50 wt% from 8.07 × 10−5 S m−1 to 8.57 × 10−5 S m−1. Ultrathin β-silver vanadium oxide nanowires synthesized by electrochemical polymerization of aniline were studied for their alternating current conductivity and dielectric properties. The structural morphology and the size of the hybrid nanowires before and after the adsorption of aniline were analyzed by using X-ray diffractometer, and an inductor–capacitor–resistance (LCR) measurement system. Moreover, electrical characterization was carried out to study the dielectric parameters as a function of frequency between 100 Hz and 5 MHz at room temperature. [ABSTRACT FROM AUTHOR]