12,744 research outputs found
Interference and Deployment Issues for Cognitive Radio Systems in Shadowing Environments
In this paper we describe a model for calculating the aggregate interference
encountered by primary receivers in the presence of randomly placed cognitive
radios (CRs). We show that incorporating the impact of distance attenuation and
lognormal fading on each constituent interferer in the aggregate, leads to a
composite interference that cannot be satisfactorily modeled by a lognormal.
Using the interference statistics we determine a number of key parameters
needed for the deployment of CRs. Examples of these are the exclusion zone
radius, needed to protect the primary receiver under different types of fading
environments and acceptable interference levels, and the numbers of CRs that
can be deployed. We further show that if the CRs have apriori knowledge of the
radio environment map (REM), then a much larger number of CRs can be deployed
especially in a high density environment. Given REM information, we also look
at the CR numbers achieved by two different types of techniques to process the
scheduling information.Comment: to be presented at IEEE ICC 2009. This posting is the same as the
original one. Only author's list is updated that was unfortunately not
correctly mentioned in first versio
AGRICULTURAL TERRORISM: POTENTIAL ECONOMIC EFFECTS ON THE POULTRY INDUSTRY IN MISSISSIPPI
An input/output model was developed to estimate the potential economic impact of intentional attacks by agricultural terrorists using Exotic Newcastle Disease (END) on the poultry industry in Mississippi. The model measured impacts in terms of income, employment, output, and tax changes in the poultry industry.Risk and Uncertainty,
Hypocenter Distribution of Low Frequency Event at Papandayan Volcano
Papandayan volcano is a stratovolcano with irregular cone-shaped has eight craters around the peak. The most active crater in Papandayan is a Mas crater. Distribution of relocated event calculated using Geiger Adaptive Damping Algorithm (GAD) shows that the epicenter of the event centered below Mas crater with maximum rms 0.114. While depth of the hypocenter range between 0-2 km and 5-6 km due to activity of steam and gas
Partisipasi Petani dalam Peningkatan Produksi Padi Sawah (suatu Kasus pada Perkumpulan Petani Pemakai Air di Desa Lalousu Kecamatan Wonggeduku Kabupaten Konawe)
This study aims to determine the participation of farmers in irrigation management and the level of farmer participation in increasing rice production. This type of research is a case study of predetermined subjects and objects. The method used in this study is a survey method, while the method for collecting data is a questionnaire. The population in this study were all farmers who were members of the P3A group. The sampling technique was carried out with Simple Random Sampling (simple random) with a sample of 46 farmers. Analysis of the data used to determine the relationship of participation of farmers using water in increasing rice production is the analysis of Chi-Square. The results of the study indicate that: 1) Participation of farmers in irrigation management activities is included in the high category or participating; and 2) there is a relationship between participation and production of paddy rice in Lalousu village, wonggeduku sub-district, konawe district
Impact of alloy disorder on the band structure of compressively strained GaBiAs
The incorporation of bismuth (Bi) in GaAs results in a large reduction of the
band gap energy (E) accompanied with a large increase in the spin-orbit
splitting energy (), leading to the condition that
which is anticipated to reduce so-called CHSH Auger
recombination losses whereby the energy and momentum of a recombining
electron-hole pair is given to a second hole which is excited into the
spin-orbit band. We theoretically investigate the electronic structure of
experimentally grown GaBiAs samples on (100) GaAs substrates by
directly comparing our data with room temperature photo-modulated reflectance
(PR) measurements. Our atomistic theoretical calculations, in agreement with
the PR measurements, confirm that E is equal to for
9. We then theoretically probe the inhomogeneous
broadening of the interband transition energies as a function of the alloy
disorder. The broadening associated with spin-split-off transitions arises from
conventional alloy effects, while the behaviour of the heavy-hole transitions
can be well described using a valence band-anticrossing model. We show that for
the samples containing 8.5% and 10.4% Bi the difficulty in identifying a clear
light-hole-related transition energy from the measured PR data is due to the
significant broadening of the host matrix light-hole states as a result of the
presence of a large number of Bi resonant states in the same energy range and
disorder in the alloy. We further provide quantitative estimates of the impact
of supercell size and the assumed random distribution of Bi atoms on the
interband transition energies in GaBiAs. Our calculations support
a type-I band alignment at the GaBiAs/GaAs interface, consistent
with recent experimental findings
AN ANALYSIS OF STRATEGIC AND PERFORMANCE CHANGES OF TRUCK CARRIERS IN THE AGRICULTURAL COMMODITY AND FOOD MARKETS
Agribusiness,
IMPACT OF STRATEGIC CHANGES ON THE PERFORMANCE OF TRUCKING FIRMS IN THE AGRICULTURAL COMMODITY TRANSPORTATION MARKET
Econometric models were developed to estimate factors that influence strategic changes and evaluate the impacts that strategic changes will have on the subsequent performance of agricultural commodity trucking firms. Results reveal that GDP and change in firm size will have positive impacts on strategic changes made by firms.Public Economics,
Isoprene oxidation by the gram-negative model bacterium variovorax sp. WS11
Plant-produced isoprene (2-methyl-1,3-butadiene) represents a significant portion of global volatile organic compound production, equaled only by methane. A metabolic pathway for the degradation of isoprene was first described for the Gram-positive bacterium Rhodococcus sp. AD45, and an alternative model organism has yet to be characterised. Here, we report the characterisation of a novel Gram-negative isoprene-degrading bacterium, Variovorax sp. WS11. Isoprene metabolism in this bacterium involves a plasmid-encoded iso metabolic gene cluster which differs from that found in Rhodococcus sp. AD45 in terms of organisation and regulation. Expression of iso metabolic genes is significantly upregulated by both isoprene and epoxyisoprene. The enzyme responsible for the initial oxidation of isoprene, isoprene monooxygenase, oxidises a wide range of alkene substrates in a manner which is strongly influenced by the presence of alkyl side-chains and differs from other well-characterised soluble diiron monooxygenases according to its response to alkyne inhibitors. This study presents Variovorax sp. WS11 as both a comparative and contrasting model organism for the study of isoprene metabolism in bacteria, aiding our understanding of the conservation of this biochemical pathway across diverse ecological niches
AN ANALYSIS OF INTERMODAL INFORMATION TECHNOLOGY USAGE BY INTERMODAL PORTS AND TERMINALS IN THE AGRICULTURAL AND FOOD- PRODUCT MARKET
Agribusiness, Research and Development/Tech Change/Emerging Technologies,
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