radiation profile
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Author(s):  
G. I. Oyet ◽  
P. Audu ◽  
B. S. Chibor

The effect of thermal radiation on the Physiochemical properties of soil around gas flare site in the Niger Delta region was assessed in Emuoha Local Government Area of River State, Nigeria, for a period of twelve months. Radiation profile was determined at different times (hours) – 6, 10, 14, 18 and 22, in the four seasons (early dry, early wet, late dry and late wet) of the year. Soil samples were taken at different depths (cm) (0-15 and 15-30) for physicochemical attributes at different distances (m) (0-150, 150-300, 300-450, 450-600 and 1000 -2000) from the flare site and thermal radiation was also determined at the respective distances. Results of effect of time and seasonal variations on radiation profile showed that environmental temperature (oC) ranged from 29.2 ± 0.3 at 22 hours of early wet season to 33.0 ± 0.4 at 14 hours of late dry season; radiation temperature ranged from 35.4 ± 1.2 at 22 hours of late wet season to 42.0 ± 1.4 at 14 hours of late dry season, while thermal radiation (w/m2) ranged from 490.83 ± 7.7 at 22 hours of late wet season to 535.69 ± 9.69 at 14 hours of late dry season. Results of effect of flare distance on physicochemical properties of soil showed that as the distance (m) from flare site increases from 0 – 150 to 1000 – 2000, the radiation intensity (w/m2) decreases from 603.84 ± 5.7 – 428.83 ± 0.75, and values of pH, OC, N, P,  and exchangeable cations - K+, Na+, Ca2+, Mg2+ increases in the range {pH (4.94 ± 0.02 – 5.50 ± 0.00), OC (1.09 ± 0.01 – 2.05 ± 0.00), N (0.07 ±0.01 – 0.09 ± 0.00), P (10.90 ± 0.03 – 12.10 ± 5.19), K+ (0.28 ± 0.01 – 1.86 ± 0.01), Na+ (0.48 ± 0.00 – 1.04 ± 0.00), Ca2+ (1.65 ± 0.01 – 2.85 ± 0.00), Mg2+ (0.73 ± 0.01 – 1.24 ± 0.01)}, These values seemed not to be affected by the thermal radiation and flare distance , oil and grease and THC decreases in the range 203.30 ± 0.88 – 61.33 ± 0.33 and 352.90 ± 2.08 – 10.04 ± 0.04 respectively. Similar trend was observed with soil samples taken at 15-30cm depth. Statistical analysis showed there is significant difference (p<0.001) in soil attributes as distance from flare distance increases. Further studies should be carried out to investigate the relationship between soil around flare site and crop performance on different agro-ecological zone of Rivers State.


2021 ◽  
Vol 2110 (1) ◽  
pp. 012007
Author(s):  
J Annovasho ◽  
V Rahayu ◽  
A Ardimas ◽  
R A Firdaus

Abstract This study aims to determine the dimensions of the antenna and reflector which can optimally work at a frequency of 2.45 GHz. A good antenna is an antenna that has high directive capability, high performance, and inexpensive. In this work, the proposed antenna model was a Bi-Circular Loop (BCL) with a reflector using a frying pan (Wajanbolic). The methods were used in this research for instance computational simulation, fabrication, and characterization. Simulations were carried out using the Finite Different Time Domain (FDTD) technique. The simulation results were compared with the measurement process. In the first simulation, four reflectors sizes could qualify as antennas, namely diameters of 309.00 mm, 335.00 mm, 364.00 mm, and 381.00 mm. The four reflectors sizes were optimized by changing the radius parameter of the BCL antenna. The best results were obtained on the reflector with a diameter of 364.00 mm and a BCL radius of 17.38 mm. The simulation results showed a radiation profile consisting of an RL value of -35.69 dB and a gain value of 16.40 dBi. Based on the fabrication and measurement of the antenna, the RL value was -54.75 dB and the directional antenna gain was 16.00 dBi. An antenna with such performance can be used as a point-to-point Wi-Fi transmitter.


Author(s):  
T. Stalin Subbiah ◽  
R. Mahesh ◽  
P. Parthiban ◽  
A. Das

The present study is aimed at evaluating the radiation profile along the coast of the Poompuhar- Nagore range, which is known to be hydrodynamically active and is enriched with anthropogenic activities. The study of radiation on the coastal belt and evaluating their dynamics (magnitude and spatio-temporal variability) is crucial both for the coastal inhabitants as well as possible exploration of rare-earth minerals. The effective gamma radiation during the new moon along the coastal range varies between 0.9 to 3.55 ?sv.h-1, respectively. The annual equivalent dose is estimated up to gamma radiation of 0.26 to 2.80 ?sv.h-1. Generally, the concentrations of the gamma radiation measured are elevated in certain areas namely Chinnagudi, Kuttiyandiyur, and Chandrapadi. In particular, the gamma radioactivity is high at Chandrapadi and Chinnagudi during the new moon as it shows considerable amounts of radiation. There is a definite variation due to the moon phase on the gamma radiation profile of the area studied. Out of the eight coastal villages under study, about 60% of the coastal line shows high levels of gamma radiation during both new moon and full moon phases.


2021 ◽  
Vol 164 ◽  
pp. 112179
Author(s):  
Diogo R. Ferreira ◽  
Pedro J. Carvalho ◽  
Ivo S. Carvalho ◽  
Chris Stuart ◽  
Peter J. Lomas

2021 ◽  
Vol 18 (01) ◽  
pp. 29-141
Author(s):  
Mohandas Pillai

We consider the Yang–Mills problem on [Formula: see text] with gauge group [Formula: see text]. In an appropriate equivariant reduction, this Yang–Mills problem reduces to a single scalar semilinear wave equation. This semilinear equation admits a one-parameter family of solitons, each of which is a re-scaling of a fixed solution. In this work, we construct a class of solutions, each of which consists of a soliton whose length scale is asymptotically constant, coupled to large radiation, plus corrections which slowly decay to zero in the energy norm. Our class of solutions includes ones for which the radiation component is only “logarithmically” better than energy class. As such, the solutions are not constructed by a priori assuming the length scale to be constant. Instead, we use an approach similar to a previous work of the author regarding wave maps. In the setup of this work, the soliton length scale asymptoting to a constant is a necessary condition for the radiation profile to have finite energy. An interesting point of our construction is that, for each radiation profile, there exist one-parameter families of solutions consisting of the radiation profile coupled to a soliton, which has any asymptotic value of the length scale.


2021 ◽  
Author(s):  
Jinran Qie ◽  
Erfan Khoram ◽  
Dianjing Liu ◽  
Ming Zhou ◽  
Li Gao

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1063
Author(s):  
Audrius Merfeldas ◽  
Pranas Kuzas ◽  
Darius Gailius ◽  
Zilvinas Nakutis ◽  
Mindaugas Knyva ◽  
...  

In this paper, the near-field radiated susceptibility pre-mapping method is proposed using the improved near-field probe power radiation profile assessment. The modelling of the electromagnetic field strength in 80–3000 MHz range in the proximity of the near-field probe was performed. The −6 dB aperture boundaries of the near-field probe and their variation, due to the proximity of the radio frequency (RF) printed circuit board (PCB) components, were determined, while the aperture map distortion, arising from the proximity of the passive RF PCB components were evaluated. The scanning path requirements for the RF susceptibility mapping were determined. The simulation of improved near-field probe absolute magnetic field strength reference map in open-air conditions is carried out in this work. The comparative analysis using the absolute maximum difference metric of orthogonal absolute magnetic field map cross-sections between the reference map and magnetic field maps affected by the proximity of the components was carried out. The experimental study of the RF amplifier stage susceptibility map with susceptibility mapping measurement results are presented in this work.


Author(s):  
Sergey Korolyov ◽  
Aleksandr Bogdanov ◽  
Sergey Shmelyov ◽  
Vladimir Biryukov

There are presented theoretical and experimental investigations of wheel steel laser thermal treatment with the use of ytterbium fiber laser. Thermal treatment modes are obtained on the basis of the mathematical modeling preliminarily carried out of the heat propagation processes by a finite element method.


Author(s):  
Audrius Merfeldas ◽  
Pranas Kuzas ◽  
Darius Gailius ◽  
Zilvinas Nakutis ◽  
Mindaugas Knyva ◽  
...  

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