Performance Analysis of Joint Relay and Transmit–Receive Antenna Selection for Low Density Parity Check-Asynchronous Distributed Space Time Block Coded Cooperative Diversity System

In this work we propose a joint relay and transmit–receive antenna selection method for amplify and forward asynchronous distributed space time block coded (ADSTBC) system. To the LDPC coded signal received from the source at the relays, we apply linear dispersion codes which are optimized over the delay profile of the system to produce the ADSTBC. Selection of the best transmit–receive antenna pair between source and selected relays, and that of between the selected relays and destination is done on the basis of instantaneous signal to noise ratio (SNR) of the respective paths. The relays and transmit-receive antenna pairs are selected by maximizing the end-to-end instantaneous SNR. Performance analysis of the system is done on the basis of pair wise error probability and outage probability (P_out).     

Crosstalk analysis in CNT bundle interconnects for VLSI application

Crosstalk noise voltage levels have been estimated at the far end of a victim line in capacitive coupled single‐walled carbon nanotube (SWCNT) bundle interconnects under the influence of interconnect dimensions. The reported work on crosstalk analysis in SWCNT bundle interconnects to date have assumed the value of coupling capacitance as equivalent to the coupling effect between metal interconnects of same dimensions. In this paper, we propose an improved model to extract inter‐bundle real‐life coupling capacitances to fill that gap. A similar analysis is performed for a copper‐based interconnect, and comparison is made with result obtained for CNT‐based interconnect at 22‐nm technology. SPICE simulation results reveal that the crosstalk noise voltage level at the far end of the victim line in CNT bundles is significantly lower than that in conventional metal (copper) conductors in three different cases, keeping the pitch fixed but varying the value of interconnect spacing and width. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Pseudo super-miscibility: Blends of semi-crystalline nylon pairs exhibiting a single Tg and a single Tm

Physical blends of nylon 6 (or nylon 66) homopolymer with random copolymers of nylon 6/nylon 66 or of nylon 6/nylon 12 were melt extruded into films and characterized by Differential Scanning Calorimetry (DSC) and X-ray Diffraction (XRD) techniques. The films containing up to 50–65% of the copolymer exhibited only a single melting temperature (T_m) corresponding to that of the pure homopolymer without any trace of the otherwise crystallizable, lower melting copolymer component. These observations are quite unusual since the binary blends of the homopolymers of nylon 6, nylon 66, and nylon 12 exhibit their characteristic 2 T_m's. That result was significant in that at least 20% nylon 6 units (T_m = 222°C) can be incorporated into nylon 66 (T_m = 262°C) without any depression either in the T_m or in the crystallinity of nylon 66 while retaining its T_m = 262°C as the only melting phase. Also, it has now become possible to develop blend compositions based on ≥ 4 polyamide moieties that exhibit a single T_g, high crystallinity, and a sigle T_m corresponding to the higest melting component. We believe that the observed phenomenon, pseudo super-miscibility, is kinetically driven (i.e., only the higher melting homopolymer crystallizes), rather than thermodynamically or crystallographically, since the structural units originate from polymers that are inherently not isomorphic. In view of the unexpected observation, at least in the field of nylons and its technological significance, we anticipate renewed interest in this area and more definitive understanding to emerge from future studies.     

Variation of major fatty acids in F8 generation of opium poppy (Papaver somniferum × Papaver setigerum) genotypes

The fatty acid compositions in F₈ genotypes of a cross between Papaver somniferum×Papaver setigerum were studied. The oil content in both species was quite variable, ie 38·0% in P setigerum and 47·8% in P somniferum, while C18 fatty acids were quite comparable. The F₈ genotypes had higher oil contents (>40%) and fatty acid concentrations than the parental species. Linoleic acid ranged between 68% (BRO 54) and 74·4% (BRO 59) and oleic acid varied between 13·6% (BRO 65) and 20·3% (BRO 54). High oleic desaturation ratio (ODR, >0·79) and C18 polyunsaturated fatty acid (>87%) with very low C18: 3 (0·37±0·01) indicate the possibility of using poppy oil for the edible oil industry. Oleic (18:1) acid was not correlated with the other fatty acids, except for significant negative correlation with linoleic (C18: 2) acid. © 1998 SCI.     

Recent Advancements in Wide Band Semiconductors (SiC and GaN) Technology for Future Devices

Silicon - Wide bandgap (WBG) semiconductor materials have the capability of making power electronic components with a smaller size, faster switching speed, more reliability, and greater efficiency...