Preferred Language
Articles
/
ijs-10164
Modified Model to Calculate Low Earth Orbit (LEO) for A satellite with Atmospheric Drag
...Show More Authors

In this paper, the satellite in low Earth orbit (LEO) with atmospheric drag perturbation have been studied, where Newton Raphson method to solve Kepler equation for elliptical orbit (i=63 , e = 0.1and 0.5, Ω =30 , ω =100 ) using a new modified model. Equation of motion solved using 4th order Rang Kutta method to determine the position and velocity component which were used to calculate new orbital elements after time step ) for heights (100, 200, 500 km) with (A/m) =0.00566 m2/kg. The results showed that all orbital elements are varies with time, where (a, e, ω, Ω) are increased while (i and M) are decreased its values during 100 rotations.The satellite will fall to earth faster at the lower height and width using big values for eccentricity (e) and (A/m) ratio. Were the results got lifetime at height = 200, e = 0.1 equal 11 days for A/m =0.02 m2/kg, while satellite's lifetime at height = 200, e = 0.1 for A/m = 0.09 m2/kg equal 6 days.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jan 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Birefringence for Elliptical-Core Fibers with Low Ellipticities
...Show More Authors

Model birefringence was measured for elliptical-core fibers with low ellipticities, note the birefringence depends strongly on the frequency, especially when fiber is being operated near the higher mode cutoff where ν  for circular fiber of the single-mode type that correspond to the birefringence maximum. When ν  this also correspond to the birefringence maximum that can be introduced in an elliptical core fiber while still operating in the single-mode regime near the higher mode cutoff. Also the birefringence is proportional to the fiber core ellipticity when core ellipticity is much less than unity, but this birefringence deviates from the linear for the large core ellipticities.

View Publication Preview PDF
Crossref
Publication Date
Mon Oct 28 2019
Journal Name
Iraqi Journal Of Science
Re-Evaluation Solution Methods for Kepler's Equation of an Elliptical Orbit
...Show More Authors

An evaluation was achieved by designing a matlab program to solve Kepler’s equation of an elliptical orbit for methods (Newton-Raphson, Danby, Halley and Mikkola). This involves calculating the Eccentric anomaly (E) from mean anomaly (M=0°-360°) for each step and for different values of eccentricities (e=0.1, 0.3, 0.5, 0.7 and 0.9). The results of E were demonstrated that Newton’s- Raphson Danby’s, Halley’s can be used for e between (0-1). Mikkola’s method can be used for e between (0-0.6).The term  that added to Danby’s method to obtain the solution of Kepler’s equation is not influence too much on the value of E. The most appropriate initial Gauss value was also determined to

... Show More
View Publication Preview PDF
Scopus (10)
Crossref (6)
Scopus Crossref
Publication Date
Sun Jan 14 2018
Journal Name
Journal Of Engineering
A Nonlinear MIMO-PID Neural Controller Design for Vehicle Lateral Dynamics model based on Modified Elman Neural Network
...Show More Authors

This paper presents a new design of a nonlinear multi-input multi-output PID neural controller of the active brake steering force and the active front steering angle for a 2-DOF vehicle model based on modified Elman recurrent neural. The goal of this work is to achieve the stability and to improve the vehicle dynamic’s performance through achieving the desired yaw rate and reducing the lateral velocity of the vehicle in a minimum time period for preventing the vehicle from slipping out the road curvature by using two active control actions: the front steering angle and the brake steering force. Bacterial forging optimization algorithm is used to adjust the parameters weights of the proposed controller. Simulation resul

... Show More
View Publication Preview PDF
Publication Date
Sun Nov 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Theoretical and experimental studies for different compounds to calculate: electronic transfer, energy gap and NLO properties
...Show More Authors

This work involves theoretical and experimental studies for seven compounds to calculate the electrons spectrum and NLO properties. The theoretical study is done by employing the Time Depending Density Functional Theory TD-DFT and B3LYP/high basis set 6-311++G (2d,2p), using Gaussian program 09. Experimental study by UV/VIS spectrophotometer device to prove the theoretical study. Theoretical and experimental results were applicable in spectrum and energy gap values, in addition to convergence theoretically the energy gap results from ΔEHOMO-LUMO and UV/VIS. spectrum. Consider the theoretical method very appropriate to compounds that absorb in vacuum UV.

View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Sat Dec 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
A Modified Method for NADH Stain That is Used to Stain a Muscle Sample From Myopathic Patient
...Show More Authors

This  srudy   aimed  to   use  a   new  concentration   from   l\!J3T (Nitroblue tetrazolium) which using NADH   stain ( by used eight different concentrations from (0.2% to 0.06% ).

That stain is a mitochondrial and cytoplasmic histochemical stain which gi ves more infom1ation about the metabolic activity of muscle fiber, so it is valuable in determining the types of muscle fibers and good fiber differentiation type {T) and type (TT)  fibers), by reducing NBT in the location of enzyme and gives a blue color in different degrees according to the types of muscle fibers, and we noticed that the concentration 0.1% from NBT gives a good result and di

... Show More
View Publication Preview PDF
Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
A Modified Key Scheduling Algorithm for RC4
...Show More Authors

Rivest Cipher 4 (RC4) is an efficient stream cipher that is commonly used in internet protocols. However, there are several flaws in the key scheduling algorithm (KSA) of RC4. The contribution of this paper is to overcome some of these weaknesses by proposing a new version of KSA coined as modified KSA . In the initial state of the array is suggested to contain random values instead of the identity permutation. Moreover, the permutation of the array is modified to depend on the key value itself. The proposed performance is assessed in terms of cipher secrecy, randomness test and time under a set of experiments with variable key size and different plaintext size. The results show that the RC4 with improves the randomness and secrecy with

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 01 2023
Journal Name
Iraqi Journal Of Physics
Calculation Mars – Earth distance and Mars orbital elements with Julian date
...Show More Authors

In this paper, the Mars orbital elements were calculated. These orbital elements—the major axis, the inclination (i), the longitude of the ascending node (W), the argument of the perigee (w), and the eccentricity (e)—are essential to knowing the size and shape of Mars' orbit. The quick basic program was used to calculate the orbital elements and distance of Mars from the Earth from 25/5/1950 over 10000 days. These were calculated using the empirical formula of Meeus, which depended on the Julian date, which slightly changed for 10000 days; Kepler's equation was solved to find Mars' position and its distance from the Sun. The ecliptic and equatorial coordinates of Mars were calculated. The distance between Mars and the center of the E

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Agricultural And Statistical Sciences
USE OF MODIFIED MAXIMUM LIKELIHOOD METHOD TO ESTIMATE PARAMETERS OF THE MULTIPLE LINEAR REGRESSION MODEL
...Show More Authors

Scopus
Publication Date
Thu May 11 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Modified Thompson –Type Testimators for the Parameters of Simple Linear Regression Model
...Show More Authors

 Dens itiad ns vcovadoay fnre Dec2isco0D,ia asrn2trcds4 fenve ns 6ocfo ts ida%n2notd, rasr sedno6t(a asrn2trcd fnre sc2a 2cynwnvtrnco co nrs wcd2 /nt sedno6t(a fan(er wtvrcd ﯿ)ﺔ mh         Dens r,ia cw asrn2trcds et/a laao vcosnyaday wcd asrn2trno( rea itdt2arads ﻘ cw sn2i%a %noatd da(dassnco 2cya%4 feao t idncd asrn2tra cw rea itdt2arad /t%ua )ﻘm ns t/tn%tl%a4 st, ﻘxh Dens ﻘx ets laao dawadday no srtrnsrnvt% %nradtrudas ts (uass icnor tlcur rea itdt2arad ﻘh         Dea aMidassncos wcd Snts4 Oato -9utday 8ddcd )O-8m toy .a%trn/a 8wwnvnaov, cw rea idcicsay asrn2trcds tda clrtnoayh 1u2adnvt% dasu%rs tda idc/nyay feao rea

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 01 2020
Journal Name
Baghdad Science Journal
A Modified Support Vector Machine Classifiers Using Stochastic Gradient Descent with Application to Leukemia Cancer Type Dataset
...Show More Authors

Support vector machines (SVMs) are supervised learning models that analyze data for classification or regression. For classification, SVM is widely used by selecting an optimal hyperplane that separates two classes. SVM has very good accuracy and extremally robust comparing with some other classification methods such as logistics linear regression, random forest, k-nearest neighbor and naïve model. However, working with large datasets can cause many problems such as time-consuming and inefficient results. In this paper, the SVM has been modified by using a stochastic Gradient descent process. The modified method, stochastic gradient descent SVM (SGD-SVM), checked by using two simulation datasets. Since the classification of different ca

... Show More
View Publication Preview PDF
Scopus (10)
Crossref (6)
Scopus Clarivate Crossref