4,538 research outputs found
Bandwidth Efficient Root Nyquist Pulses for Optical Intensity Channels
Indoor diffuse optical intensity channels are bandwidth constrained due to the multiple reflected paths between the transmitter and the receiver which cause considerable inter-symbol interference (ISI). The transmitted signal amplitude is inherently non-negative, being a light intensity signal. All optical intensity root Nyquist pulses are time-limited to a single symbol interval which eliminates the possibility of finding bandlimited root Nyquist pulses. However, potential exists to design bandwidth efficient pulses. This paper investigates the modified hermite polynomial functions and prolate spheroidal wave functions as candidate waveforms for designing spectrally efficient optical pulses. These functions yield orthogonal pulses which have constant pulse duration irrespective of the order of the function, making them ideal for designing an ISI free pulse. Simulation results comparing the two pulses and challenges pertaining to their design and implementation are discussed
Greenhouse screening for Fusarium wilt resistance in lupine
Fusarium wilt can cause total crop failure. Evaluation of Ffusarium resistance in heavily infected soil were performed in a grenhouse where the dominant fusarium species in the soil in descending order was F. oxysporum then F. avenaceum, F. culmorum, F. solani, F. gibbosum. Large fusarium wilt presure was observed and fully susceptible lines were completely destroyed by Fusarium wilt caused by F. oxisporum. Segregation in F2 and F3 in L. angustifolius showed that resistant genotypes have two dominant non-allelic resistance genes to wilt. We call this gene Relation to fusarium oxisporum (Rfo1,Rfo2). Susceptible genotypes have either two wild genes (++ ++) or one wild and one dominant resistant gene (++ Rfo2 Rfo2, or Rfo1Rfo1 ++). Crossing ‘++ Rfo2Rfo2’ to ‘Rfo1Rfo1 ++’ segregates in 9:7 resistant to susceptible in F2, respectively. The same segregation was observed by crossing ‘Rfo1Rfo1 Rfo2Rfo2’ to ‘++ ++’. We recommend the use of these resistant genes in breeding in areas with potential Fusarium wilt problems
An Extended Huckel Theory based Atomistic Model for Graphene Nanoelectronics
An atomistic model based on the spin-restricted extended Huckel theory (EHT)
is presented for simulating electronic structure and I-V characteristics of
graphene devices. The model is applied to zigzag and armchair graphene
nano-ribbons (GNR) with and without hydrogen passivation, as well as for
bilayer graphene. Further calculations are presented for electric fields in the
nano-ribbon width direction and in the bilayer direction to show electronic
structure modification. Finally, the EHT Hamiltonian and NEGF (Nonequilibrium
Green's function) formalism are used for a paramagnetic zigzag GNR to show
2e2/h quantum conductance.Comment: 5 pages, 8 figure
Italian Colonisation & Libyan Resistance the Al-Sanusi of Cyrenaica (1911 – 1922)
This paper seeks to analyse Italian Colonialism in Libya from 1911-1922 against the backdrop of the anti-colonial Sanusi Order. Part A seeks to set the colonial context and ambitions of the European powers in North Africa (and the Maghrib). Part B will outline the emergence of the Sanusi resistance as well as the origins and evolution of the Order from mid-1800’s to a religious-politico organisation by 1911. Part C will investigate the Turco-Italian War (1911-12) whereby Italy officially occupied Libya, it will examine the role of the Sanusi resistance during the first colonial war, subsequent conflicts and the years of the Accords (when a semblance of peace appeared to be on the horizon) and conclude briefly on the impact of the Sanusi Order
A theoretical model for single molecule incoherent scanning tunneling spectroscopy
Single molecule scanning tunneling spectroscopy (STS), with dephasing due to
elastic and inelastic scattering, is of some current interest. Motivated by
this, we report an extended Huckel theory (EHT) based mean-field
Non-equilibrium Green's function (NEGF) transport model with electron-phonon
scattering treated within the self-consistent Born approximation (SCBA).
Furthermore, a procedure based on EHT basis set modification is described. We
use this model to study the effect of the temperature dependent dephasing, due
to low lying modes in far-infrared range for which hw<<kT, on the resonant
conduction through highest occupied molecular orbital (HOMO) level of a phenyl
dithiol molecule sandwiched between two fcc-Au(111) contacts. Furthermore, we
propose to include dephasing in room temperature molecular resonant conduction
calculations.Comment: 12 pages, 5 figure
Effects of Neutrino Inverse Seesaw Mechanism on the Sparticle Spectrum in CMSSM and NUHM2
We study the implications of the inverse seesaw mechanism (ISS) on the
sparticle spectrum in the Constrained Minimal Supersymmetric Standard Model
(CMSSM) and Non-Universal Higgs Model (NUHM2). Employing the maximal value of
the Dirac Yukawa coupling involving the up type Higgs doublet provides a 2-3
GeV enhancement of the lightest CP-even Higgs boson mass. This effect permits
one to have lighter colored sparticles in the CMSSM and NUHM2 scenarios with
LSP neutralino, which can be tested at LHC14. We present a variety of LHC
testable benchmark points with the desired LSP neutralino dark matter relic
abundance.Comment: 18 pages, 10 figures and 2 table
Accelerated modernity
This paper aims to show how current undergraduate students use social media in their daily lives, taking the first ten minutes of the day as a concentrated insight into their priorities of practice. The work draws on primary data from four focus groups of UK business students in higher education. Through the application of Rosa’s construct of social acceleration, initial findings indicate a hierarchy of priorities, shaped by economic, cultural and structural drivers in what social media is engaged with, in what sequence, and for what purpose. These choices reflect acceleration in the changes to the technology, the pace of social changes and the accelerated expectations of the pace of life. This article seeks to reimagine transmedia in the context of social media identity in an accelerated modernity. Here we have the intersection of three important rapidly changing constructs for the analysis of the use of media. These are the widespread, ubiquitous use of social media, the acceleration of late modernity and the impact of transmedia practice on how users engage with media
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