Study of Different Rates of Application of Pendimethalin and Acetochlor onWeed Infestation and Grain Yield of Fababean

A fababean weed control trial was conducted during the 2016-2017 growing season. The aim of this study is to investigate the effect of two preemergence herbicides Pendimethalin and Acetochlor on weed infestation in a fababean crop. Dominant weed botanical families in the experimental site belong to Asteraceae and Poaceae. Results showed that the improvement of fababean grain yield depends on the weed control efficacy. Treatment with Pendimethalin at 1228 g/ha widely decrease fababean weed infestations recording 91.7% and 90.56 respectively on visual efficacy rating and weed biomass reduction. Acetochlor at 1050 g/ha recorded the lowest efficacies 53.3% and 62.1% respectively on visual efficacy rating and weed biomass reduction. Plots treated with Pendimethalin at 1228 g/ha recorded the best yields with an average of 3.32 tons / ha

Devil's Thorn (Emex spinosa (L.) Campd.) Response to Tribenuron-methyl and 2,4-D in Ouazzane Region of Morocco

A soft wheat weed control trial was conducted during the 2016-2017 growing season. The aim of this study is to investigate the effect of two postemergence herbicides Tribenuron-methyl and 2,4 D on Emex spinosa infestation in a soft wheat crop. Treatments consist on two Tribenuron-methyl rates of application and two 2,4-D rates of application. The experimental design was a random block with tree repetitions and observations were made 60 days after application of herbicides. Results showed that treatment with Tribenuron-methyl at 9.50g/ha and 14.25g/ha widely decrease E. spinosa infestations. Tribenuron-methyl at 9.50g/ha recorded 87.8%, 86.1% and 90.5% respectively on E. spinosa density reduction, E. spinosa height reduction, and E. spinosa dry biomass reduction. Tribenuron-methyl at 14.25g/ha recorded 96.3%, 95.5% and 98.7% respectively on E. spinosa density reduction, E. spinosa height reduction, and E. spinosa dry biomass reduction. 2,4 D at 400g/ha and 600g/ha recorded the lowest efficacies that did not exceed 75.2% in all observed parameters

On the performance of adaptive coding schemes for energy efficient and reliable clustered wireless sensor networks

Clustering is the key for energy constrained wireless sensor networks (WSNs). Energy optimization and communication reliability are the most important consideration in designing efficient clustered WSN. In lossy environment, channel coding is mandatory to ensure reliable and efficient communication. This reliability is compromised by additional energy of coding and decoding in cluster heads. In this paper, we investigated the trade-offbetween reliability and energy efficiency and proposed adaptive FEC/FWD and FEC/ARQ coding frameworks for clustered WSNs. The proposed schemes consider channel condition and inter-node distance to decide the adequate channel coding usage. Simulation results show that both the proposed frameworks are energy efficient compared to ARQ schemes and FEC schemes, and suitable to prolong the clustered network lifespan as well as improve the reliability

New high-Q discrete-time LC bandpass filter design with center frequency broadband tuning

Discrete-time switched-capacitor filters have been in wide-spread used for a few years, for the realization of stable, accurate and high quality filters. This paper describes the design of a new 8-path pseudo switched-capacitor LC bandpass filter and its command circuit made up by a ring voltage controlled oscillator (VCO) with 'XOR' gates. The proposed architecture presents the possibility of tuning over a frequency broadband allowing to sweep different channels with a high quality factor. This circuit is intended to replace the surface acoustic wave (SAW) filters in broadband wireless applications. Experimental results carried out on a prototype show quality factors up to 200, and a tunable center frequency range of 300 MHz [250-550 MHz]

Atelier 1: Mesures par analyseur de réseaux

National audienc

Investigation of the aging of power GaN HEMT under operational switching conditions, impact on the power converters efficiency

International audienceThis paper investigates the aging of a 650 V, 30 A GaN HEMT power transistor under operational switching conditions. The switching stress respects the Safe Operation Area (SOA) of the tested transistor. The aging campaign lasted 1008 h and was carried out through a developed switching application with high power efficiency. The global aging results show the degradation of five parameters: drain current ID, on-state resistance RDS(ON), transconductance gm, gate leakage current IGSS, and threshold voltage VTH. The major causes that affect the reliability of the GaN HEMT are hard switching, long time of test and high intensity of the stress. The existence of trapped charge in the gate-drain access region after aging is demonstrated using pulsed measurements. The effects of this degradation on power converters are studied by modeling the static characteristics of the aged GaN HEMT using an accurate method based on the Levenberg-Marquardt Algorithm. The accuracy and consistent convergence of the developed SPICE model provide a good way to investigate the reliability of GaN HEMTs by a simulation approach

Investigation of the aging of power GaN HEMT under operational switching conditions, impact on the power converters efficiency

International audienc

Atelier 1: Mesures par analyseur de réseaux

National audienc

Atelier 1: Mesures par analyseur de réseaux

National audienc