Preferred Language
Articles
/
alkej-156
Aircraft Lateral-Directional Stability in Critical Cases via Lyapunov Exponent Criterion
...Show More Authors

Based on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore the variation of Lyapunov exponent parameter as function of time is introduced. The numerical result indicated that the system became lightly damped at high angle of attack with increasing the amplitude of aircraft state variables limit cycle. A good agreement between the numerical result and published work is obtained for the onset of limit cycle oscillation, almost at .

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Dec 02 2012
Journal Name
Baghdad Science Journal
Stability of Back Propagation Training Algorithm for Neural Networks
...Show More Authors

In this paper, we derive and prove the stability bounds of the momentum coefficient µ and the learning rate ? of the back propagation updating rule in Artificial Neural Networks .The theoretical upper bound of learning rate ? is derived and its practical approximation is obtained

View Publication Preview PDF
Crossref
Publication Date
Tue Jul 30 2024
Journal Name
Academia Open
Positioning Preterm Newborns for Cardiorespiratory Stability A Global Insight
...Show More Authors

Publication Date
Fri Mar 28 2003
Journal Name
Journal Of Engineering
STABILITY OF UNREINFORCED AND REINFORCED EMBANKMENTS ON SOFT SOILS
...Show More Authors

Publication Date
Fri Mar 14 2003
Journal Name
Journal Of Engineering
Slope Stability of Embankments by the Finite Element Method
...Show More Authors

Publication Date
Thu Dec 31 2015
Journal Name
Kerbala Journal Of Pharmaceutical Sciences
Investigation the Factors Affecting on Gatifloxacin Eye Drop Stability
...Show More Authors

This research included the study of different factors that may effect on gatifloxacin stability (anew quinolone synthetic antibacterial agent) in its aqueous solution in order to develop and optimize the best delivary of the drug to the eye (as eye drop) with maximum local concentration and minimum systemic absorption and toxicity.Different formulas of gatifloxacin solution for ophthalmic use (0.3%)w/v were prepared in citrate, acetate,citrate/phosphate and phosphate buffers,their tonicity adjusted with suitable quantity of sodium chloride.The effect of different factors that might affectthe stability of gatifloxacin in its prepared ophthalmic solution was studied and determined spectrophotometrically at 287 nm. The results showed t

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
The emotional stability development, Ages 11 to 14 Years
...Show More Authors

The current research aims to identify 1) the differences of emotional stability development level according to the variable of age; and 2) the differences of emotional stability development level according to the variable of gender (male, female). This study employed a descriptive approach, whereby a total of 165 primary and secondary school student was randomly selected from the directorate of AL -rusafa side (1st rusafa) of Baghdad province to constitute the sample of the study. The questionnaire was created based on the previous testes and studies that are relevant to emotional stability, and all its psychometrics features were examined. The researcher analyzed the data using SPSS statistic

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 20 2022
Journal Name
2022 4th International Conference On Current Research In Engineering And Science Applications (iccresa)
Noise Detection and Removing in Heart Sound Signals via Nuclear Norm Minimization Problems
...Show More Authors

Heart sound is an electric signal affected by some factors during the signal's recording process, which adds unwanted information to the signal. Recently, many studies have been interested in noise removal and signal recovery problems. The first step in signal processing is noise removal; many filters are used and proposed for treating this problem. Here, the Hankel matrix is implemented from a given signal and tries to clean the signal by overcoming unwanted information from the Hankel matrix. The first step is detecting unwanted information by defining a binary operator. This operator is defined under some threshold. The unwanted information replaces by zero, and the wanted information keeping in the estimated matrix. The resulting matrix

... Show More
View Publication
Scopus Crossref
Publication Date
Sun Jun 03 2018
Journal Name
Baghdad Science Journal
Spectrophotometric Determination of Sulphite in Various Water Samples Via Chromium-1,5-Diphenylcarbazide Complex
...Show More Authors

A simple and rapid spectrophotometric method for the determination of sulphite SO3-2 is described. The method is based on the rapid reduction of known amount of chromate CrO4-2 in the presence of sulphite in acidic medium of 2N H2SO4. The amount of excess of chromate was measured after it reactions with 1,5-diphenylcarbazide which finally gives a pink-violet, water soluble and stable complex, which exhibit a maximum absorption at 542 nm. Beer's law was obeyed in the concentration range from 0.004-6.0 µg of sulphite in a final volume of 25 ml with a molar absorbtivity of 4.64×104 l.mol-1.cm-1, Sandal's sensitivity index of 0.001724 ?g .cm-2 and relative standard deviation of ±0.55 - ±0.83 depending on the concentration level. The present

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Wed Aug 23 2017
Journal Name
Journal Of Physics G: Nuclear And Particle Physics
Shell closures in Fl superheavy isotopes via determination of alpha decay preformation factor
...Show More Authors

View Publication
Scopus (7)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Fri Sep 25 2020
Journal Name
International Journal Of Drug Delivery Technology
Simultaneous Determination of Trace Mefenamic Acid in Pharmaceutical Samples via Flow Injection Fluorometry
...Show More Authors

Mefenamic acid belongs to non-steroidal anti-inflammatory drugs that are used widely for the treatment of analgesia. Our aim from this study is to establish a new assay for the quantitative determination of mefenamic acid (MFA) in the pharmaceutical sample by two sensitive and rapid flow injection-fluorometric methods. A homemade fluorometer was used in fluorescence measurements, which using solid-state laser diode 405 and 532 nm as a source, combined with a continuous flow injection technique. The first method depends on the effect of MFA on calcein blue (CLB) fluorescence at 405 nm. Another method is a study of rhodamine-6G (Rh-6G) fluorescence after adding MFA, and recording at 532 nm. Optimum parameters as fluorescent dye concen

... Show More
View Publication
Scopus (5)
Crossref (4)
Scopus Crossref