THE COMPARISON OF THE METHODS ESTIMATING THE FRACTIONAL DIFFERENCES OF PARAMETER AND ITS DEPENDENCE ON ESTIMATION THE BEST LINEAR MODEL OF TIME SERIES IN THE ENVIRONMENTAL FIELD
Publication Date
Thu Dec 28 2017
Journal Name
Al-khwarizmi Engineering Journal
Aircraft Lateral-Directional Stability in Critical Cases via Lyapunov Exponent Criterion
wing rock
nonlinear dynamic system
limit cycle oscillation
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
... Show MorePublication Date
Sun Oct 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Statistical testing mediation in structural equations models variables with practical application
/ الانموذج الهيكلي
الوساطة
الخطوات السببية
structural model
mediation
steps causal.
Abstract:
This study is studied one method of estimation and testing parameters mediating variables in a structural equations model SEM is causal steps method, in order to identify and know the variables that have indirect effects by estimating and testing mediation variables parameters by the above way and then applied to Iraq Women Integrated Social and Health Survey (I-WISH) for year 2011 from the Ministry of planning - Central statistical organization to identify if the variables having the effect of mediation in the model by the step causal methods by using AMOS program V.23, it was the independent variable X represents a phenomenon studied (cultural case of the
Publication Date
Thu Jun 20 2019
Journal Name
Baghdad Science Journal
Social Worked-Examples Technique to Enhance Student Engagement in Program Visualization
Engagement
Introductory Programming Education
Program Visualization
Worked-example
Learning programming is among the top challenges in computer science education. A part of that, program visualization (PV) is used as a tool to overcome the high failure and drop-out rates in an introductory programming course. Nevertheless, there are rising concerns about the effectiveness of the existing PV tools following the mixed results derived from various studies. Student engagement is also considered a vital factor in building a successful PV, while it is also an important part of the learning process in general. Several techniques have been introduced to enhance PV engagement; however, student engagement with PV is still challenging. This paper employed three theories—constructivism, social constructivism and cognitive load t
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(2)
Publication Date
Wed Feb 01 2023
Journal Name
Baghdad Science Journal
3-D Packing in Container using Teaching Learning Based Optimization Algorithm
Container
Gravitational Search Algorithm
Mathematics
Teaching Learning Based Optimization Algorithm
3-D Packing
The paper aims to propose Teaching Learning based Optimization (TLBO) algorithm to solve 3-D packing problem in containers. The objective which can be presented in a mathematical model is optimizing the space usage in a container. Besides the interaction effect between students and teacher, this algorithm also observes the learning process between students in the classroom which does not need any control parameters. Thus, TLBO provides the teachers phase and students phase as its main updating process to find the best solution. More precisely, to validate the algorithm effectiveness, it was implemented in three sample cases. There was small data which had 5 size-types of items with 12 units, medium data which had 10 size-types of items w
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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Low Loss in a Gas Filled Hollow Core Photonic crystal fiber
"Photonic crystal
microstructure fabrication
optical fibers"
The work in this paper focuses on the experimental confirming of the losses in photonic crystal fibers (PCF) on the transmission of Q-switched Nd:YAG laser. First HC-PCF was evacuated to 0.1 mbar then the microstructure fiber (PCF) was filled with He gas & gas. Second the input power and output power of Q-switched Nd:YAG laser was measured in hollow core photonic bandgap fiber (HCPCF). In this work loss was calculated in the hollow core photonic crystal fiber (HCPCF) filled with air then N2, and He gases respectively. It has bean observed that the minimum loss obtained in case of filling (HC-PCF) with He gas and its equal to 15.070 dB/km at operating wavelength (1040-1090) nm.
(2)
Publication Date
Wed Sep 15 2021
Journal Name
Al-academy
Dramatic wonder in children's theater performances: ميادة مجيد امين اسماعيل الباجلان
miraculous
dramatic
children's theater
Dramatic wonders at children's theatre shows Search summary The importance of the current study is to present an important concept, from the point of view of those interested in the field of literature and the theater of the child, namely (miraculous) because it represents an innate tendency immersed in the child's mind, and therefore it is easy to impress him when attracting him with a text and a presentation addressed to him, to achieve the aesthetic and intellectual vision, so the problem of research was in the following question: (dramatic wonders in children's theater performances) and the importance of research lies in the importance of the importance of the role of wonder for dramatic discourse in children's theatre performances,
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Publication Date
Fri Sep 01 2017
Journal Name
Pak. J. Pharm. Sci.
(6)
Publication Date
Mon Jan 01 2024
Journal Name
Anais Da Academia Brasileira De Ciências
Morphological study for Accipitrid birds (Accipitridforms, Accipitridae) in Iraq; part two
A part two of Accipitridae Family members that belong to three genera:
Circus
Gyps
and Neophron were documented as morphometrics
distribution ranges
and conservation status were reviewed and comprehensively discussed. A total of
29 voucher specimens belong to six species which are conserved in the “Iraq Natural
History Research Center and Museum INHM” as follow: Marsh Harrier Circus aeruginosus
(Linnaeus
1758)
Hen Harrier Circus cyaneus (Linnaeus
1766)
Montagus Harrier Circus
pygargus (Linnaeus
1758)
Pallid Harrier Circus macrourus (Gmelin
1770)
Egyptian
vulture Neophron percnopterus (Linnaeus
1758)
and Griffon vulture Gyps fulfus (Hablitz
1783). The results revealed significant criteria about near threatened NT species IUCN
and Birdlife International listed as Pallid Harrier Circus macrourus
and Endangered
(EN) species as Egyptian vulture Neophron percnopterus globally decreasing population
trend.
Publication Date
Tue Jul 28 2020
Journal Name
Iraqi Journal Of Science
Bacteremia Associated with Pressure Ulcers at Alyarmuk Teaching Hospital in Baghdad
Fifty patients(24 female and 26 male)with pressure ulcersassociated with different diseasesand attending AL-yarmouk Teaching Hospital in Baghdad were selected in this study. The duration of sample collection was from March to December 2018. All blood samples collected from patients were submitted to a blood culturing technique to examine bacteremia. The results showed that12 blood bacterial isolates were obtained. The isolated bacteria were subjected to Vitek-2, which is an accurate identification technique. The results of the blood culturing technique revealed that 33.3% were Gram negative bacteria, while 66.6% were Gram positive. Diagnosis by Vitek-2 showed that 33.3% wereStaphylococcus spp. , 33.3% were Enterococcus
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(1)
Publication Date
Thu Nov 01 2018
Journal Name
Advances In Animal And Veterinary Sciences