3,323 research outputs found
Estimation of Rain Attenuation at EHF bands for Earth-to-Satellite Links in Bangladesh
Due to heavy congestion in lower frequency bands, engineers are looking for
new frequency bands to support new services that require higher data rates,
which in turn needs broader bandwidths. To meet this requirement, extremely
high frequency (EHF), particularly Q (36 to 46 GHz) and V (46 to 56 GHz) bands,
is the best viable solution because of its complete availability. The most
serious challenge the EHF band poses is the attenuation caused by rain. This
paper investigates the effect of the rain on Q and V bands' performances in
Bangladeshi climatic conditions. The rain attenuations of the two bands are
predicted for the four main regions of Bangladesh using ITU rain attenuation
model. The measured rain statistics is used for this prediction. It is observed
that the attenuation due to rain in the Q/V band reaches up to 150 dB which is
much higher than that of the currently used Ka band. The variability of the
rain attenuation is also investigated over different sessions of Bangladesh.
The attenuation varies from 40 dB to 170 dB depending on the months. Finally,
the amount of rain fade required to compensate the high rain attenuation is
also predicted for different elevation angles.Comment: Int'l Conf. on Electrical, Computer and Communication Engineering
(IEEE sponsored), Cox's Bazar, Bangladesh, February 2017, pp. 589-59
Hybrid CNN-SVD Based Prominent Feature Extraction and Selection for Grading Diabetic Retinopathy Using Extreme Learning Machine Algorithm
Funding Information: This work was supported in part by the National Research Foundation of Korea-Grant funded by the Government of Korea (Ministry of Science and ICT) under Grant NRF-2020R1A2B5B02002478, and in part by Sejong University through the Faculty Research Program under Grant 20212023Peer reviewedPublisher PD
Long - term fertilization effect of organic carbon and total nitrogen on floodplain soil
Soil organic matter is the most often reported indicator of soil quality and productivity and an evidence of previous soil management. Therefore, in 2017, a laboratory incubation study was carried out in the experimental filed of Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh, Bangladesh under control condition at 25°C for 104 days to investigate the influence of long term manuring and fertilization on soil respiration by means of C mineralization. Soil samples were collected from floodplain soil with rice-rice cropping pattern at Bangladesh Agricultural University (BAU) experimental farm having eight treatments. Long term (33 years) application of fertilizers and manure resulted in significant differences in soil organic carbon, total N content, and soil pH KCl between the treatments. The soil organic carbon and total N content varied among the different treatments from14.9 g OC kg-1 to 17.0 g OC kg-1 and1.60 g N kg-1 (control) to 1.78 g N kg-1 (application of NPK). The soil pH varied among the different treatments from 5.65(application of NK) to 4.89 (application of N). This result indicates that more stable organic carbon was formed in NPK treated soil which is less prone to de-composition if present crop management has been changed
MSGM : A Markov Model Based Similarity Guide Matrix for Optimising Ordered Problems by Balanced-Evolution Genetic Algorithms
Peer reviewe
- …