A test of independence based on a generalized correlation function

In this paper, we propose a novel test of independence based on the concept of correntropy. We explore correntropy from a statistical perspective and discuss its properties in the context of testing independence. We introduce the novel concept of parametric correntropy and design a test of independence based on it. We further discuss how the proposed test relaxes the assumption of Gaussianity. Finally, we discuss some computational issues related to the proposed method and compare it with state-of-the-art techniques.     

Characteristics of slurry coated CdSeTe films

CdSe_xTe_1?x films were deposited by the slurry coating technique using CdSe_xTe_1?x powders synthesized in the laboratory. X-ray diffraction studies indicated the formation of a hexagonal phase. From EDAX compositional analysis, the individual concentrations of Se and Te in the films were estimated. Analysis of the optical data indicate the band gap to vary from 1.44 to 1.68 eV as the value of ‘x’ changes from 0 to 1. XPS analysis was also carried out on the films. The films were used as photoanodes in polysulphide electrolyte and it was observed that the films with composition CdSe_0.6Te_0.4 exhibited the maximum photoactivity. The Mott–Schottky plot indicated an n-type behaviour. Spectral response measurements were made and the electrodes exhibited a quantum efficiency of 0.6.     

Contact-Barrier Free,High Mobility,Dual-Gated Junctionless Transistor Using Tellurium Nanowire

The gate-all-around nanowire transistor, due to its extremely tight electrostatic control and vertical integration capability, is a highly promising candidate for sub-5 nm technology nodes. In particular, the junctionless nanowire transistors are highly scalable with reduced variability due to avoidance of steep source/drain junction formation by ion implantation. Here a dual-gated junctionless nanowire p-type field effect transistor is demonstrated using tellurium nanowire as the channel. The dangling-bond-free surface due to the unique helical crystal structure of the nanowire, coupled with an integration of dangling-bond-free, high quality hBN gate dielectric, allows for a phonon-limited field effect hole mobility of 570 cm² V⁻¹ s⁻¹ at 270 K, which is well above state-of-the-art strained Si hole mobility. By lowering the temperature, the mobility increases to 1390 cm² V⁻¹ s⁻¹ and becomes primarily limited by Coulomb scattering. The combination of an electron affinity of ≈ 4 eV and a small bandgap of tellurium provides zero Schottky barrier height for hole injection at the metal-contact interface, which is remarkable for reduction of contact resistance in a highly scaled transistor. Exploiting these properties, coupled with the dual-gated operation, we achieve a high drive current of 216 μA μm⁻¹ while maintaining an on-off ratio in excess of 2 × 10⁴. The findings have intriguing prospects for alternate channel material based next-generation electronics.     

Composite-two-phase wavelength reservation scheme for dynamic optical networks

An enhanced hybrid scheme of wavelength reservation for dynamic wavelength routed optical networks is proposed. The performance of a newly introduced composite-two-phase reservation protocol (C2P-RP) is evaluated and compared with the existing hybrid reservation protocol. By offering connection requests an enhanced scope of finding an end-to-end available wavelength, the C2P-RP scheme shows improved connection-request blocking performance.     

Structural and electrical properties of brush plated ZnTe films

Zinc telluride thin films were deposited by the brush plating technique at a potential of −0.90 V (SCE) on conducting glass and titanium substrates at different temperatures in the range 30–90 °C. The films were polycrystalline in nature with peaks corresponding to the cubic phase. Direct band gap of 2.30 eV was observed. XPS studiers indicated the formation of ZnTe. Depth profiling studies indicated a uniform distribution of Zn and Te throughout the entire thickness. EDAX measurements were made on the films and it was found that there was a slight excess of Te. The carrier concentration was found to vary from 10¹⁴–10¹⁵ cm⁻³ with increase of substrate temperature. The mobility was found to vary from 5 to 60 cm² V⁻¹ s⁻¹.     

Effect of deposition time on optical and luminescence properties of ZnS thin films prepared by photo assisted chemical deposition technique

Photo assisted chemical deposition method (PCD) is a new procedure for the deposition of compound semiconducting materials which is less explored. In this method the deposition is carried out with the irradiation of UV light on the reaction bath. PCD scores advantages for its low cost, use of flexible substrates and capability of large area deposition compared to other chemical methods like chemical bath deposition (CBD), electro chemical deposition (ECD), etc. Zinc sulfide films have been deposited on glass substrate by aqueous alkaline solution comprised of zinc nitrate, hydrazine hydrate, ammonium nitrate, ammonia and thiourea. The samples were prepared under UV illumination for different durations and characterized. The thickness of the samples increases with the deposition time. XRD patterns revealed the crystalline nature of samples with more number of dips. Optical study showed a low absorbance and constant transparency throughout the visible region disclosing the stiochiometric nature of the film. Obtained band gap energies were in good agreement with the theoretical value. Photoluminescence spectra showed two blue emission bands around 450 and 470 nm, and the intensity was found to depend on the thickness of the films.     

Properties of brush plated CdxZn1−xTe thin films

Cd_xZn_1−xTe (0  x  0.5) thin films were deposited for the first time by the brush plating technique using cadmium sulphate, zinc sulphate and tellurium dioxide precursors. The deposition current density was maintained at 100 mA cm⁻². X-ray diffraction studies indicated the formation of cubic phase with (1 1 1), (2 2 0), (3 1 1) orientations. From optical absorption measurements the band gaps of the films are found to be direct. AFM studies indicate a surface roughness around 54 Å. Density of the films of different composition has been estimated. Laser Raman studies indicated CdTe like LO and TO phonons.     

Bandpass solar exoatmospheric irradiance and Rayleigh opticalthickness of sensors on board Indian Remote Sensing Satellites-1B, -1C,-1D, and P4

This paper reports the bandpass solar exoatmospheric irradiance and Rayleigh optical thickness for six categories of sensors, namely, the linear imaging self scanning sensor (LISS)-I, -II, -III, the wide field sensor (WiFS), the panchromatic (PAN), and the ocean color monitor (OCM) which have been flown on Indian Remote Sensing Satellites (IRS)-1B, -1C, -1D, and -P4 platforms, based on laboratory measurements of relative spectral response (RSR) of each band. These estimates have been compared with similar contemporary international sensors     

Address Generation Optimization for Embedded High-Performance Processors: A Survey

Nowadays embedded systems are growing at an impressive rate and provide more and more sophisticated applications characterized by having a complex array index manipulation and a large number of data accesses. Those applications require high performance specific computation that general purpose processors can not deliver at a reasonable energy consumption. Very long instruction word architectures seem a good solution providing enough computational performance at low power with the required programmability to speed up the time to market. Those architectures rely on compiler effort to exploit the available instruction and data parallelism to keep the data path busy all the time. With the density of transistors doubling each 18 months, more and more sophisticated architectures with a high number of computational resources running in parallel are emerging. With this increasing parallel computation, the access to data is becoming the main bottleneck that limits the available parallelism. To alleviate this problem, in current embedded architectures, a special unit works in parallel with the main computing elements to ensure efficient feed and storage of the data: the address generator unit, which comes in many flavors. Future architectures will have to deal with enormous memory bandwidth in distributed memories and the development of address generators units will be crucial for effective next generation of embedded processors where global trade-offs between reaction-time, bandwidth, energy and area must be achieved. This paper provides a survey of methods and techniques that optimize the address generation process for embedded systems, explaining current research trends and needs for future.

Thermal distribution calculations for block level placement in embedded systems

Reliability is a very important concern for the embedded systems. Thermal distribution has become an important reliability concern for today’s integrated circuits and these circuits are being used increasingly in embedded systems. In traditional design flows, the temperature of the chip is assumed to be uniform across the substrate. However, non-uniform thermal distribution can be a major source of inaccuracy in delay and clock skew computations, and can have an impact on elctromigration reliability and self-heating effects for today’s very deep submicron technology. Hence, it has become necessary to obtain design with uniform temperature distribution to ensure minimum temperature gradient and avoid hot spots across the chip area. This will minimise reliability problems during the operation of the chip. The uniform temperature distribution can be achieved by appropriate placement of circuit blocks during the physical design. In this paper, thermal distribution of single chip embedded system on silicon is discussed. The thermal distribution calculations require evaluation of switching activity factor of circuit blocks. This factor is determined by computing activities of the blocks based on the application software of embedded system.