EC Analysis of Multi-Antenna System over 5G and Beyond Networks and its Application to IRS-Assisted Wireless Systems

Wireless Personal Communications - Recently, the theory of effective rate has attracted much attention, since it can take the delay aspect into account when performing channel capacity analysis. In...     

Photophysical studies of copolymers of N‐vinylcarbazole

The absorption, fluorescence excitation and emission spectroscopy, and time‐dependent spectrofluorimetry have been used to study the photophysics of copolymers of N‐vinylcarbazole with different monomers like vinyl acetate, methyl acrylate, methyl methacrylate, butyl acrylate, and butyl methacrylate in dichloromethane. In all the copolymers and at different N‐vinylcarbazole content, the absorption spectra reflect only the monomer carbazole units. The two kinds of excited monomer species of N‐vinylcarbazole are present in S₁ state. Short‐lived (～3 ns) excited monomer decays forming low energy excimer obtained by the complete overlap of the excited carbazole monomer. The long‐lived excited monomer (～8 ns) decays to ground state without formation of any excimer. The high energy excimer is relatively short‐lived and is formed by the partial overlap of the carbazole units. The presence of bulky group in the copolymer chain hinders the formation of excimers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 372–380, 2006     

Security Functional Components for Building a Secure Network Computing Environment

ABSTRACT

It is difficult to define reliable security policy components that should be applied to validate a secure computing environment. The job gets further complicated when one has to deal with multiple policies in single computing environment. This paper demonstrates how we can overcome the difficulties of defining reliable security components by using evaluation criteria. In this paper we use common criteria to derive the security functional components for a multipolicy-based network computing environment. In the verification process, the derived policy components are related to the specific security objectives of the network communication environment. The evidence listed in the case study supports the claims that the proposed network security policy interpretation framework is a complete and cohesive set of requirements.     

Preparation of cobalt ferrite from the thermolysis of cobalt tris(malonato)ferrate(III)trihydrate precursor

Thermal decomposition of cobalt tris(malonato)ferrate(III)trihydrate precursor, Co₃[Fe(CH₂C₂O₄)₃]·3H₂O has been investigated from ambient temperature to 600 °C in static air atmosphere using various physico-chemical techniques, i.e. TG–DTG–DSC, XRD, Mössbauer and IR spectroscopic techniques. The precursor undergoes dehydration and decomposition simultaneously to yield cobalt malonate and iron(II) malonate intermediates at 205 °C. At higher temperature (325 °C) these intermediate species undergo exothermic decomposition to yield CoO and α-Fe₂O₃, respectively. Finally cobalt ferrite, CoFe₂O₄, has been obtained as a result of solid–solid reaction between Fe₂O₃ and CoO at a temperature (380 °C) much lower than that of ceramic method. SEM analysis of the final thermolysis product reveals the formation of monodisperse cobalt ferrite nano-particles with an average particle size of 45 nm. Magnetic studies show that these particles have a saturation magnetization of 3095 G and Curie temperature of 504 °C. Lower magnitude of these parameters as compared to the bulk values is attributed to the smaller particle size.     

Three-Dimensional Visualization of Transgenic Tobacco Leaves

We have done a three-dimensional visualization of transgenic tobacco (Nicotiana tabacum) leaves for the study of chloroplast gene expression and regulation. The aim was to visualize tobacco leaves shot with tungsten particles. These tungsten particles were coated with the foreign DNA and shot into the leaf using the biolistic technique of DNA insertion. The visualization can be used to examine the leaves to gauge the efficiency of the shooting process, i.e.,to see what parts of the leaves have been effectively penetrated by the DNA-coated tungsten particles and also to judge the depth of penetration. The image data for the 3D visualization was collected at planes 10 microns apart, using a prototype version of a High Numerical Aperture Reflecting Microscope. The raw image data collected from the microscope was restored using the Row Action Projection (RAP) algorithm and the Partial Minimization and Constrained Iteration (PCMI) algorithm. These restored images were then used for 3D visualization using the Visualization Toolkit.     

Magnetorheological finishing of grooved drum surface and its performance analysis in winding process

The fine level finishing of grooved drum surfaces is an essential requirement for enhancing the performance of the winding machines in today’s textil     

Wetted Wall Cyclones for Bioaerosol Sampling

A wetted wall bioaerosol sampling cyclone with an aerosol sampling flow rate of 1250 L/min and a continuous liquid outflow rate of about 1 mL/min was developed by upgrading an existing system. The aerosol-to-hydrosol collection efficiency curve for the upgraded device was shown to have a cutpoint of 1.2 μ m aerodynamic diameter (AD) and an average collection efficiency of 90% over the size range of 2 to 10.2 μ m AD. Tests with near-monodisperse cells and clusters of Bacillus atrophaeus (aka BG) spores showed an average aerosol-to-hydrosol collection efficiency of 98% over the size range from 1.7 to 9.8 μ m AD. Pressure drop across the cyclone, which is also the ideal specific power, was 5.5 kPa (22 inches H₂O). Stokes scaling was used to design geometrically similar cyclones with nominal air sampling flow rates of 100 and 300 L/min. Extensive tests were performed with the 100 L/min unit and check tests with the 300 L/min. Results with the scaled units showed similar, although somewhat lower collection efficiencies than the 1250 L/min device, but with lower consumption of liquid and lower pressure losses. For the 100 L/min cyclone, the cutpoint of the aerosol-to-hydrosol efficiency curve was 1.2 μ m AD, and the average collection efficiency for single cells and clusters of BG spores was 86% over a size range of 1.2 to 8.3 μ m AD. Also, for the 100 L/min cyclone, typical output liquid flow rates were 100 μ L/min, and the pressure loss was 1.6 kPa (6.4 inches H₂O).