Simplified Levenberg-Marquardt Algorithm based PAPR Reduction for OFDM System with Neural Network

In recent years, OFDM is the key transmission technique in the communication system. This is because of the high channel estimation, strong against multipath fading and increased spectral efficiency. Because of the independently modulated subcarriers, the Peak to Average Power Ratio (PAPR) is very high in OFDM systems. Previously we use a number of PAPR reduction schemes using clipping, adding windows etc. But in these methods we cannot achieve the optimum reduction or the BER performance is high or the system is very complex. On considering the BER performance and system complexity we employ a new method based on the Neural Network (NN). In this new method we achieve significant PAPR reduction with great BER improvement and complexity reduction. In the simulations we seen that the PAPR reduction and BER performance are very good. DOI: 10.17762/ijritcc2321-8169.15080

Growth of staghorn coral Acropora aspera (Dana) (Scleractinia: Acropridae) in relation to environmental factors at Kavaratti atoll (Lakshadweep Islands), India

Skeletal extension and calcification were measured over 2 years in branches of the staghorn coral Acropora aspera from a shallow-water si te. Correlations were made between growth parameters and environmental variables monitored over the same period. Calcification .varied significal)tly (9.4- 17.4 mg. 28d - ') than skeletal extension (3.1 -4.7 mm. 28d -') and unlike extension, it varied significantly between seasons with lowest values during southwest monsoon (June-September). Seasonal reduction in calcification was probably associated with the reduced availability oflight due to increased cloud cover and sediments in water. Extension, however, seemed to be under the direct influence of currents and sediments. The effect of environmen tal factors seemed more critical to calcification

Skeletal extension of staghorn coral Acropora formosa in relation to environment at Kavaratti atoll (Lakshadweep)

Growth study for 2 years, in rspect of skeletal extension, was conducted in situ at Kavaratti atoll. Average annual rate of extension of branches was 7.9 ± 2 cm for first year and 8.2 ± 1.8 em for second year. Growth of individual branches exhibited intracolony variations. Monthly rate of growth was found to be slower during monsoon (June-September) when compared to premonsoon (February-May) .and postmonsoon (October-January) seasons. Environmental conditions at the study area, with the exceptIOn of the amount of sediments in water, seemed conducive to the growth of Acropora formosa

Managing human resource management tensions in project-based organisations: evidence from Bangalore

The article analyses the methods used by a large Indian software company to manage HRM tensions with arising from its activities as a project based organisation. These measures are found to be only partially successful

Altered vitamin B12 metabolism in the central nervous system is associated with the modification of ribosomal gene expression: new insights from comparative RNA dataset analysis

Recent studies have confirmed the direct role of vitamin B12 (VitB12) in the central nervous system (CNS) homeostasis; nevertheless, the detailed mechanisms are poorly understood. By analyzing RNA-Seq and microarray datasets obtained from databanks, this study aims to identify possible basic mechanisms, related to the brain, involved in altering the gene expression under VitB12 deficiency mimicking conditions. The database inquiry returned datasets generated from distinctly heterogeneous experimental sets and considering the quality and relevance requirements, two datasets from mouse and one from rat models were selected. The analyses of individual datasets highlighted a change in ribosomal gene expression in VitB12 deficiency mimicking conditions within each system. Specifically, a divergent regulation was observed depending on the animal model: mice showed a down regulation of the ribosomal gene expression, while rats an upregulation. Interestingly, E2f1 was significantly upregulated under VitB12 deficiency mimicking conditions in the animal models, with a greater upregulation in rats. The rat model also revealed putative E2F1 Transcription Factor Binding Sites (TFBSs) in the promoter of the differently regulated genes involved in ribosomal gene expression. This suggested the possibility that E2F1, being greater expressed in rats, could activate the ribosomal genes having E2F1 TFBSs, thus giving a plausible explication to the divergent regulation observed in animal models. Despite the great diversity of the experimental sets used to generate the datasets considered, a common alteration of the ribosomes exists, thereby indicating a possible basic and conserved response to VitB12 deficiency. Moreover, these findings could provide new insights on E2F1 and its association with CNS homeostasis and VitB12 deficiency

Microstrip antenna with DGS based on CSRR array for WiMAX applications

This paper reports a novel method for designing a miniaturized microstrip antenna with DGS based on CSRR array which operates in the frequency of 2.6GHz for low band WiMAX application. The proposed antenna is designed using ANSYS HFSS simulation software. The antenna with optimized parameters is fabricated using FR-4 substrate of thickness 1.6 mm. The simulated and measured performances of the antenna in terms of return loss, directivity and radiation patterns are presented in this work. When Complimentary Split Ring Resonators (CSRRs) array are placed on the ground plane, the resonant frequency is shifted  to a lower value and patch size is reduced .The measurements were taken and compared with the simulated results. The performance characteristics obtained from the measurements show that the proposed antenna is suited for WiMAX application at 2.6GHz

Evaluation of Cytotoxic Potential of Acorus calamus Rhizome

The present work evaluated the cytotoxicity of methanolic and aqueous extracts of rhizome of Acorus calamus Linn. which is a well known medicinal plant used in traditional treatment. Both extracts were found to be cytotoxic as determined by Allium cepa root tip assay and XTT assay in MDA-MB-435S and Hep3B cell lines. Results of the study indicate that the plant possesses antitumor properties and may serve as a potential source for investigation and development of anticancer drugs

A blinded determination of H0H_0 from low-redshift Type Ia supernovae, calibrated by Cepheid variables

Presently a ${>}3\sigma$ tension exists between values of the Hubble constant $H_0$ derived from analysis of fluctuations in the Cosmic Microwave Background by Planck, and local measurements of the expansion using calibrators of type Ia supernovae (SNe Ia). We perform a blinded reanalysis of Riess et al. 2011 to measure $H_0$ from low-redshift SNe Ia, calibrated by Cepheid variables and geometric distances including to NGC 4258. This paper is a demonstration of techniques to be applied to the Riess et at. 2016 data. Our end-to-end analysis starts from available CfA3 and LOSS photometry, providing an independent validation of Riess et al. 2011. We obscure the value of $H_0$ throughout our analysis and the first stage of the referee process, because calibration of SNe Ia requires a series of often subtle choices, and the potential for results to be affected by human bias is significant. Our analysis departs from that of Riess et al. 2011 by incorporating the covariance matrix method adopted in SNLS and JLA to quantify SN Ia systematics, and by including a simultaneous fit of all SN Ia and Cepheid data. We find $H_0 = 72.5 \pm 3.1$ (stat) $\pm 0.77$ (sys) km s$^{-1}$ Mpc$^{-1}$ with a three-galaxy (NGC 4258+LMC+MW) anchor. The relative uncertainties are 4.3% statistical, 1.1% systematic, and 4.4% total, larger than in Riess et al. 2011 (3.3% total) and the Efstathiou 2014 reanalysis (3.4% total). Our error budget for $H_0$ is dominated by statistical errors due to the small size of the supernova sample, whilst the systematic contribution is dominated by variation in the Cepheid fits, and for the SNe Ia, uncertainties in the host galaxy mass dependence and Malmquist bias.Comment: 38 pages, 13 figures, 13 tables; accepted for publication in MNRA

Carrier Transport in High Mobility InAs Nanowire Junctionless Transistors

Ability to understand and model the performance limits of nanowire transistors is the key to design of next generation devices. Here, we report studies on high-mobility junction-less gate-all-around nanowire field effect transistor with carrier mobility reaching 2000 cm2/V.s at room temperature. Temperature-dependent transport measurements reveal activated transport at low temperatures due to surface donors, while at room temperature the transport shows a diffusive behavior. From the conductivity data, the extracted value of sound velocity in InAs nanowires is found to be an order less than the bulk. This low sound velocity is attributed to the extended crystal defects that ubiquitously appear in these nanowires. Analyzing the temperature-dependent mobility data, we identify the key scattering mechanisms limiting the carrier transport in these nanowires. Finally, using these scattering models, we perform drift-diffusion based transport simulations of a nanowire field-effect transistor and compare the device performances with experimental measurements. Our device modeling provides insight into performance limits of InAs nanowire transistors and can be used as a predictive methodology for nanowire-based integrated circuits.Comment: 22 pages, 5 Figures, Nano Letter

Quintuplets: record of a premature delivery

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