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Problem statement: Microstructure of the grain will influence the properties of a polycrystalline manganites when different dopant is introduced. In this work, an effort had been made to investigate the influence of Ca, Ba and Sr substitution in La site. Approach: Polycrystalline manganites compound of [La.sub.0.67][A.sub.0.33]Mn[O.sub.3] where A = Ba, Sr and Ca had been prepared via conventional solid-state reaction method. The structure, microstructure, magnetic and electrical properties had been investigated using XRD, SEM, VSM and four-point probe techniques. Results: XRD spectrums showed that LBMO and LCMO were in single-phase orthorhombic structure whereas LSMO was rhombohedral structure. Scanning electron micrographs showed that LSMO had smaller average grain size as compared to LBMO. However, for LCMO, there was no clear grain boundary that can be observed and all the grains were well connected. The difference in the microstructure image might be due to the variance A-site cation that differs in grain growth. The Curie temperature, [T.sub.c] of LBMO and LSMO was 343.0 and 363.5 K, respectively. But the [T.sub.c] for LCMO was lower then 300 K. The [T.sub.p] for LCMO was 215 K while it was near or above 300K for LBMO and LSMO. All samples showed extrinsic Magnetoresistance (MR) effect. Higher MR was observed well below [T.sub.c] or [T.sub.p] where MR value increased monotonically with the decrease of temperature. This was associated with the different grain and grain boundary formation when different cation was substituted. LCMO displayed the highest low-field MR value (-15.82% at 0.2 T, 90 K) and high-field MR (-25.60% at 1 T, 300 K). Conclusion: Hence, electrical and magnetic transition temperature ([T.sub.p] and [T.sub.c]) were affected by the average A-site cation radius. Key words: Ceramic, low field magnetoresistance, magnetoresistance, INTRODUCTION In recent year there has been a lot of research study in Colossal Magnetoresistance (CMR) effects in rare-earth manganite perovskite with general formula [La.sub.[1-x]][A.sub.x]Mn[O.sub.3] (A = Ba, Sr, Pb [...]

The new video coding standard, H.264/MPEG-4 AVC, uses variable block sizes ranging from 4 x 4 to 16 x 16 in interframe coding. This new feature has achieved significant coding gain compared to coding a macroblock (MB) using fixed block size. However, this feature results in extremely high computational complexity when brute force rate distortion optimization (RDO) algorithm is used. This paper proposes a fast intermode decision algorithm to decide the best mode in intercoding. It makes use of the spatial homogeneity and the temporal stationarity characteristics of video objects. Specifically, spatial homogeneity of a MB is decided based on the MB's edge intensity, and temporal stationarity is decided by the difference of the current MB and it colocated counterpart in the reference frame. Based on the homogeneity and stationarity of the video objects, only a small number of intermodes are selected in the RDO process. The experimental results show that the fast intermode decision algorithm is able to reduce on the average 30% encoding time, with a negligible peak signal-to-noise ratio loss of 0.03 dB or, equivalently, a bit rate increment of 0.6%. Index Terms--Video coding, H.264, AVC, RDO, homogeneity, stationarity, inter mode.

Rate constants for the reaction H + NO2 --> OH + NO are measured. The temperature range of 1100-2000 K in reflected shock wave experiments is used for this purpose and the theoretical results are combined with modern dynamical theory to rationalize the thermal rate behavior.

Inner product evaluation can be considered to be basic to all digital signal processing algorithms. Distributed arithmetic {DA) is a bit serial memory-oriented method that implements inner products. In DA, memory increases exponentially as the number of coefficients increases. This deters the use of DA in the implementation of DSP algorithms. This paper explores the possibility of combining DA principles with the residue number system (RNS) to exploit the advantages of both. A new technique for the computation of the inner product in the RNS domain using modular multipliers and DA principles is proposed. The resulting architecture is elegant, uses minimum memory and adders, and hence is VLSI efficient. The proposed architecture is extremely efficient in terms of speed and does not involve conversion of data into residues although computation is performed in residue domain. Index Terms - Distributed arithmetic, modular multiplier, residue number system.

A novel Markov random field model for estimating dense motion and uncovered background fields in images, is presented.

Penicillium marneffei is a thermally dimorphic fungus that can cause severe opportunistic infections in endemic regions of Southeast Asia, particularly in individuals infected with human immunodeficiency virus-1, but has rarely been reported in solid organ transplant recipients. Herein, we report the first case, to our knowledge, of P. marneffei infection in a lung transplant recipient, occurring in a 41-year-old woman 28 months post lung transplantation, after recent travel to Vietnam. We have reviewed the literature to derive some management principles for this rare infection in this clinical context. The number of P. marneffei infections in transplant recipients may increase, as a result of increasing rates of transplantation and travel to endemic areas. [ABSTRACT FROM AUTHOR]