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Aircraft Lateral-Directional Stability in Critical Cases via Lyapunov Exponent Criterion
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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 .

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Publication Date
Mon Oct 30 2023
Journal Name
Digest Journal Of Nanomaterials And Biostructures
Concentration effect on the vibrational and electronic properties of MgXZn7-XO7 wurtzoids nanostructure via DFT
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In the present work, the ternary compound MgxZn7-x O7Wurtzoid with variable Zn and Mg contents was analyzed using density functional theory with B3LYP 6-311G**basis set. The electronic and vibrational properties of MgxZn7-xO7 wurtzoids, were investigated, including energy gaps, bond lengths, spectral properties, such like infrared spectra and Raman. IR and Raman spectra were compared with experimental longitudinal optical modes frequency results. The theoretical results agree well with experiments and previous data. It has been found that the energy gap is increasing with the increased Mg concentration, and that the longitudinal optical position exposes a UV shift movement with an increase in the concentration.

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Publication Date
Sun Nov 30 2014
Journal Name
International Journal Of Advanced Research In Science, Engineering And Technology
Structural Characteristics and photoconductivity of Cerium doped Zinc Sulfide Nanoparticles synthesized via coprecipitation method
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ZnS:Ce3+ nanoparticles were prepared by a simple microwave irradiation method under mild condition. The starting materials for the synthesis of ZnS:Ce3+ quantum dots were zinc acetate (R & M Chemical) as zinc source, thioacetamide as a sulfur source, cerium chloride as cerium source and ethylene glycol as a solvent. All chemicals were analytical grade products and used without further purification. The quantum dots of ZnS:Ce3+ with cubic structure were characterized by X-ray powder diffraction (XRD), the morphology of the film is seen by scanning electron microscopy (SEM) also by field effect scanning electron microscopy (FESEM) and XRD. Upon exposure to 460 nm light at zero bias voltage, ZnS:Ce3+/p-Si showed a high sensitivity of 4000% an

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Publication Date
Tue Jul 01 2014
Journal Name
Political Sciences Journal
Political pluralism between rejection and acceptance Astrobiological study of the most prominent contemporary Islamic trends
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التعددية السياسية بين الرفلض والقبول دراسة نظرية لأبرز الاتجاهات الاسلامية المعاصرة

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Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Educational And Psychological Researches
الفكــر التـــربـــوي عنـــد ابو يوسف يعقوب بن اسحق الكنــــدي ( دراسة نظرية )
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Every era characterizes with its thought and life philosophy , where Muslims left behind them educational and intellectual heritage we should proud of it because it reflects the image of past and lights the way of present and future path where we should make use of it to fit with our statuesque and contemporary issues because we don’t know about it but little as result of ignorance or imitation of the western culture.

      It’s wrong to regard heritage from the past but aphasia of Islamic and Arab genies that its roots tracing back to past and extending to future .

      Islamic Arab educational thought regards one of the ric

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Publication Date
Sun Jun 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
أستخدام نظرية الخيارات في أدارة المخاطرة في المصارف الأسلاميه دراسه نظريه- أستطلاعيه في المصرفين الأسلاميين في الأردن
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- المقدمهIntroduction    

الخيارات أحدى الأدوات المالية المشتقة التي تشتق قيمتها من قيمة الموجود الأساسي
Underlying Asset، وقد يكون الموجود الأساسي سهما عاديا أو مؤشر أسهم أو عقد مستقبلية سلع أو عقد مستقبلية على أوراق المديونية . وبالرغم من أن الدلائل تشير إلى أن التعامل بالخيارات يعود إلى أوائل القرن السادس العشر الميلادي آلا انه ونتيجة للعديد من الابتكارات ال

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Publication Date
Sat Mar 02 2019
Journal Name
Biochem. Cell.arch.
EVALUATION OF PRIMARY IMPLANTS STABILITY IN IMMEDIATE AND DELAYED TREATMENT PROTOCOLS ACCORDING TO BONE DENSITY, JAWS, GENDER AND AGE UTILIZING PERIOTEST M DEVICE
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Publication Date
Thu Apr 01 2021
Journal Name
Annals Of The Romanian Society For
Relation Study between Chromogranin a and Other Clinical Biomarker in Iraqi Children with Growth Hormone Deficiency Undergo Treated Via Recombinant Growth Hormone
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Growth hormone deficiency is a condition that occurs when a limited volume of growth hormone is released by the pituitary gland since growth hormone deficiency causes growth delays, short stature, and overall physical development delays. symptoms differ based on the age at which they occur .Aim of this study Estimating the level of growth hormone serotonin ,IGF-1 and Chromogranin A before and after with treatment recombinant growth hormone and It is the first study in Iraq that sheds light on the relationship between Chromogranin and other variables ( somatostatin, IGF-1,GH) ,also the prediction of Chromogranin A as a newly biochemical marker in children with growth hormone deficiency. In this study, 30 samples were collected from children

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Publication Date
Thu Jun 29 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Emulsion Liquid Membrane for Pesticides Removal from Aqueous Solution: Emulsion Stability, Extraction Efficiency and Mass Transfer Studies
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The current study investigated the stability and the extraction efficiency of emulsion liquid membrane (ELM) for Abamectin pesticide removal from aqueous solution. The stability was investigated in terms of droplet emulsion size distribution and emulsion breakage percent. The proposed ELM included a mixture of corn oil and kerosene (1:1) as a diluent, Span 80 (sorbitan monooleate) as a surfactant and hydrochloric acid (HCl) as a stripping agent without utilizing a carrier agent. Parameters such as homogenizer speed, surfactant concentration, emulsification time and internal to organic volume ratio (I/O) were evaluated. Results show that the lower droplet size of 0.9 µm and higher stable emulsion in terms of breakage percent of 1.12 % we

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Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
Study the Relationship between Beta Decay Stability of Nuclide and its Shape for Some even-even Isobars
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The aim of this work is to learn the relationship of the stability of (β) emitter isobars with their shape for some isobaric elements with even mass number (A=152 - 162). To reach this goal firstly the most stable isobar have been determined by plotting mass parabola (plotting the binding energy (B.E) as a function of the atomic number (Z)) for each isobaric family. Then three-dimensional representation graphics for each nucleus in these isobaric families have been plotted to illustrate the deformation in the shape of a nucleus. These three-dimensional representation graphics prepared by calculating the values of semi-axis minor (a), major (b) and (c) ellipsoid axis’s. Our results show that the shape of nuclides which is represented the

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Publication Date
Fri Dec 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
Determination of Implant Primary Stability: A Comparison of the Surgeon’s Tactile Sense and Objective Measurements
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Background: Evaluation and measurement of primary stability could be achieved by several methods, including the resonance frequency analysis (RFA) and implant insertion torque (IT) values. The need for a sufficient primary stability, guaranteed by an adequate insertion torque and implant stability quotient values, increased its importance mainly in one stage implants or in immediate loading protocols. The aims of this study was to find if there is a correlation between the peak insertion torque (PIT) and ISQ values of implants inserted in the jaws of different bone quality which regarded as two important clinical determinant factors for prediction of implant primary stability, and to evaluate and compare whether an experienced clinician cou

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