Information technology
Riyam Alaa Johni; Kanar Roshen Tariq; Roshen Tariq Ahmadhamdi; David Iyan Forsyth
Abstract
This paper presents a theoretical investigation on a type of Fiber Optic Sensing system used for seismic monitoring which incorporates an array of Fiber Bragg Gratings (FBGs) in the sensing medium. An interferometry array contains a group of interferometry sub-arrays, every sub-array including a plurality ...
Read More
This paper presents a theoretical investigation on a type of Fiber Optic Sensing system used for seismic monitoring which incorporates an array of Fiber Bragg Gratings (FBGs) in the sensing medium. An interferometry array contains a group of interferometry sub-arrays, every sub-array including a plurality of interferometry. Each interferometer in a sub-array is realized with a particular pair of fiber Bragg gratings and a sensing length of optical fiber located between the respective pair of fiber Bragg gratings. The fiber Bragg gratings in every respective couple of fiber Bragg gratings have a similar characteristic wavelength that is altered from the characteristic wavelength of every other couple of fiber Bragg gratings in the sub-array. The sub-arrays are interconnected to minimize the common-wavelength crosstalk among the sensors in the overall interferometry array. Our work focuses on investigating the selection of the optimum wavelength for use in the system. The study was performed using state-of-the-art simulation techniques for strain and temperature changes in the FBG sensor array. The cumulative results obtained can be used to help designers produce an optimized performance for similar fiber optic hydrophones in the future. It has been shown that the wavelength 1300nm region gives the best performance in this type of fiber optic hydrophone system.
Physics
Miran Hama Rahim Saeed
Abstract
In this article, two wideband microstrip rectangular patch antennas have been designed and simulated for V band communication systems at resonant frequencies 45 GHz and 60 GHz. Rogers RO4730G3 is used as substrate dielectric with dielectric constant 2.98. The dimensions of the antennas are 6.23mm*6.7mm*0.7mm ...
Read More
In this article, two wideband microstrip rectangular patch antennas have been designed and simulated for V band communication systems at resonant frequencies 45 GHz and 60 GHz. Rogers RO4730G3 is used as substrate dielectric with dielectric constant 2.98. The dimensions of the antennas are 6.23mm*6.7mm*0.7mm and 6mm*6.4mm*0.7mm respectively, with very simple geometrical configuration. To investigate the performance, the designs were then simulated using (CST) Studio Suite software package. The dimensions have been well studied and optimized to obtain acceptable results of Voltage Standing Wave Ration (VSWR), return loss, gain, bandwidth (BW) and radiation pattern. The 45 GHz antenna provides a gain of 6.73 dBi with the BW of 5.5 GHz and 1.03 of VSWR. Meanwhile, the 60 GHz design offers 6.92 dBi of gain with BW of 11.57 GHz and 1.05 of VSWR. The achieved results illustrate that both designs provide a good performance and are applicable for future 5G communication systems or any applications in the V band region.
Mathematic
Arkan Nawzad Mustafa; Hanaa Jamal Ahmad
Abstract
In this paper, the effect of contaminated object on an SIRS Model with vaccination and hospitalization compartments is modeled. Positivity and boundedness properties of the solutions of model are proved, basic reproduction number of the model is founded through criteria which make the eigen values of ...
Read More
In this paper, the effect of contaminated object on an SIRS Model with vaccination and hospitalization compartments is modeled. Positivity and boundedness properties of the solutions of model are proved, basic reproduction number of the model is founded through criteria which make the eigen values of the Jacobean matrix at the disease free equilibrium point, negative. Globally stability analysis of the disease free equilibrium point is proved when the basic reproduction number is less than unity and the vaccination efficacy approaches unity. The existence, uniqueness of the endemic equilibrium point are investigated when the basic reproduction number greater than unity. Parameter values regarding to spreading covid-19 in Kurdistan region are estimated. Finally, sensitivity analysis of the reproduction number is carried out.