Grey system theory is a multidisciplinary scientific approach, which deals with systems that have partially unknown information (small sample and uncertain information). Grey modeling as an important component of such theory gives successful results with limited amount of data. Grey Models are divided into two types; univariate and multivariate grey models. The univariate grey model with one order derivative equation GM (1,1) is the base stone of the theory, it is considered the time series prediction model but it doesn’t take the relative factors in account. The traditional multivariate grey models GM(1,M) takes those factor in account but it has a complex structure and some defects in " modeling mechanism", "parameter estimation "and "model structure", So that traditional GM(1,M) submitted to many trials of optimizations to getting rid this defects. This research shows the characteristics of the traditional GM(1,M), the problems it suffer from, the method of getting rid of such problems and presents two optimized multivariable grey model of one order derivative equation. the first one is called the Optimized Grey Model abbreviated as OGM(1, M) by adding the linear correction term h1(M-1)and the grey action quantity term (h2) to the traditional model GM(1,M) the latter is called Optimized Background value Grey Model OBGM(1,M) by optimizing the Background value of the last model OGM(1,M). We use two A realistic data represents the water consumption in Baghdad at the period (2016-2022) to compare the two optimized models with the traditional represents the water consumption in Baghdad at the period (2016-2022)). we use the mean absolute percentage error (MAPE) and the determination coefficient R2. To compare the two optimized model with traditional one. The results show that the two optimized have less values than the those of the traditional model GM(I,M), and that verify the correctness of defects analysis of GM(1,M).
A Comparison of Traditional and Optimized Multiple Grey Regression Models with Water Data Application
Ordinary least squares
Grey Models
Multiple Regression Model
Background value
mean absolute percentage error criterion.
Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Study of effect acidic solution (HCl) and (EP/Al2O3 & EP/ TiO2) hybrid on thermal conductivity of epoxy resin.
This research studies the effect of adding micro
nano and hybrid by ratio (1:1) of (Al2O3
TiO2) to epoxy resin on thermal conductivity before and after immersion in HCl acid for (14 day) with normality (0.3 N) at weight fraction (0.02
0.04
0.06
0.08) and thickness (6mm). The results of thermal conductivity reveled that epoxy reinforced by (Al2O3) and mixture (TiO2 Al2O3) increases with increasing the weight fraction
but the thermal conductivity (k) a values for micro and Nano (TiO2) decrease with increasing the weight fraction of reinforced
while the immersion in acidic solution (HCl) that the (k) values after immersion more than the value in before immersion.
This research studies the effect of adding micro, nano and hybrid by ratio (1:1) of (Al2O3,TiO2) to epoxy resin on thermal conductivity before and after immersion in HCl acid for (14 day) with normality (0.3 N) at weight fraction (0.02, 0.04, 0.06, 0.08) and thickness (6mm). The results of thermal conductivity reveled that epoxy reinforced by (Al2O3) and mixture (TiO2+Al2O3) increases with increasing the weight fraction, but the thermal conductivity (k) a values for micro and Nano (TiO2) decrease with increasing the weight fraction of reinforced, while the immersion in acidic solution (HCl) that the (k) values after immersion more than the value in before immersion.
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Publication Date
Wed Jan 01 2020
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees20
Change detection of the land cover for three decades using remote sensing data and geographic information system
The changes in the land cover using geographical information systems and remote sensing techniques for the period (1990 - 2019) for part of the Baghdad governorate in central Iraq are detected and monitored. In this research
four satellite scenes with different sensors were used the TM
ETM+
and OLI
which were obtained by Landsat-5
Landsat-7 and Landsat-8 satellites
respectively. Maximum likelihood method supervised classification is adopted as the main classifier to distinguish different land cover types in the study region. The results showed that there are ten different classes in the values of their reflectance. This study proved that any landcover of the earth’s surface can be studied and determined by its spectral characteristics. The change for each class of the land cover for the study area was determined within the study period. The results of the study confirmed the possibility of identifying the types of land cover and finding the percentage of changes that occur in it and detecting it with high efficiency using the remote sensing technique.
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Publication Date
Mon Nov 01 2010
Journal Name
Al-nahrain Journal Of Science
Chemical Elements Diffusion in the Solar Interior
The standard solar model and equation of state have been used to study relative diffusion of Hydrogen and Helium in the present time for solar interior
as a function of distance and depth from the center of the star. The effects of temperature and density on diffusion velocity for these chemical elements have been explaned.
It is found that heat flow which is arising from these reactions leads to an increase in helium diffusion velocity
while the temperature and density leading to a decrease in Hydrogen diffusion velocity. This means that Hydrogen behaves inversely with that for helium does through these reactions. Accordingly
diffusion percentages for Hydrogen
Helium and other Heavy Elements could be determined for the main sequence stars and white dwarf stars.
Publication Date
Fri Mar 01 2019
Journal Name
Applied Acoustics
Theoretical model of absorption coefficient of an inhomogeneous MPP absorber with multi-cavity depths
Micro-perforated panel (MPP) absorber has been known as an alternative absorber to classical porous material given its facile installation
long durability
environmental friendliness and attractive appearance. Extensive studies of MPP absorber proposing the improvement of its absorption frequency bandwidth have been published. This study presents a MPP absorber introduced with inhomogeneous perforations and with multi-cavity depths. The MPP is divided into two sub-area
where each area has different hole diameter
perforation ratio and a separated backed cavity depth. The acoustic impedance is modelled using electrical equivalent circuit and the absorption coefficient is calculated under normal-incidence of sound. It is found that the inhomogeneous MPP can have good bandwidth of absorption by designing the sub-MPP of smaller perforation ratio with large hole diameter and the one having the larger perforation ratio with smaller hole diameter. The absorption bandwidth can be conveniently controlled by adjusting the cavity depth of each sub-MPP. The results from the experimental work show good agreement with the theoretical model.
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Publication Date
Thu Dec 19 2024
Journal Name
Journal Of Studies And Researches Of Sport Education
The effect of using the educational bag on the level of learning some offensive skills with the epee weapon
The effect of using the educational bag on the level of learning some offensive skills with the epee weaponDr. Lamia Hassan Al-Diwan
D. Fatima Abdel-Maliki
Dr. Kholoud Laith Abdel Karim2005 Technical and technological development has been increasing day after day and has included all areas of life
including the educational process
which has benefited from technologies such as (computer
video
and pictorial models) in introducing them as tools to aid the learning process. Educational packages have proven their effectiveness in education as they prepare learners with different areas of experience. Sensory audio-visual
through which the learner acquires different educational experiences through interaction
practice
participation
and communication with the data of the surrounding environment through the diversity of knowledge sources that suit his inclinations and needs. The research aimed to prepare an educational bag to teach some offensive skills in the epee weapon. And to find out the effect of using the proposed educational bag on the level of learning some offensive skills in the epee weapon. We hypothesized that the proposed educational package has a positive impact on the level of learning some offensive skills with the epee weapon. There were statistically significant differences in testing the level of learning some offensive skills with the epee weapon between the post-tests of the experimental and control groups
and in favor of the experimental group. The researchers used the experimental method to suit the nature of solving the research problem
and the research sample was chosen intentionally from the girls’ fencing club players (beginners) in the governorate. Basra for the year 2005. The number of players was (16)
which represented the entire study population. The experiment was conducted in the sports hall of the South Oil Sports Club in Basra. We concluded that the educational package has a positive impact on the level of learning some offensive skills in the epee weapon. There were statistically significant differences in the learning level test for some offensive skills in the epee weapon between the experimental group and the control group in the post-tests and in favor of the experimental group. We recommended the necessity of using the proposed educational curriculum to learn some offensive skills in the epee weapon in fencing lessons or in sports clubs. Adopting modern techniques in training
teaching or teaching fencing skills and searching for new methods. Conducting similar studies on other skills or different samples.Keywords: educational bag
offensive skills with an epee weapon
fencing game. Teaching methods. Basra Girl Sports ClubLamya Hassan Aldewan [email protected] of Basra - College of Education and Sports Scienceshttps://orcid.org/0000-0003-0377-6915
Keywords
educational bag
offensive skills with an epee weapon
fencing game. Teaching methods. Basra Girl Sports Club
Publication Date
Fri Jul 29 2022
Journal Name
Journal For Vascular Ultrasound
A Comparative Study of the Right and Left Carotid Arteries in Relation to Age for Patients With Diabetes and Hypertension
Introduction:
Introduction: Age
hypertension
and diabetes can cause significant alterations in arterial structure and function
including
changes in lumen diameter (LD)
intimal-medial thickness (IMT)
flow velocities
and arterial compliance. These are also considered
risk markers of atherosclerosis and cerebrovascular disease. A difference between right and left carotid artery blood flow and
IMT has been reported by some researchers
and a difference in the incidence of nonlacunar stroke has been reported between
the right and left brain hemispheres. The aim of this study was to determine whether there are differences between the right and
left common carotid arteries and internal carotid arteries in patients with hypertension and diabetes for 2 age groups.
Methods: We studied 250 patients with both diabetes and hypertension. Patients were divided into 2 age groups with the
old age group being 56 to 75 years and the young age group 35 to 55 years. The bilateral common carotid and internal carotid
arteries were evaluated with B-mode ultrasound and Doppler examinations. The LD and IMT were measured for both common
carotid arteries
and spectral waveform parameters and indices were recorded for both internal carotid arteries.
Results: The difference in LD between the left and right common carotid arteries for the old age group was 11.64% and for the
young age group was 6.42%
with significant P values of <.05 for both age groups. The difference in IMT between the left and
right common carotid arteries was 18.27% in the old age group compared with 15.38% in the young age group
with significant
P values of <.05. There was a difference in peak systolic velocity between the left and right internal carotid arteries of 4.85%
in the old age group which was not significant
compared with 14.28% in the young age group with a significant P value <.05
whereas the difference in end-diastolic velocity between the left and right internal carotid arteries was not significant for both
age groups. Differences between the right and left internal carotid arteries for resistive index
pulsatility index
and pressure
gradient were significant only in the young age group.
Conclusion: We found significant differences between the right and left common carotid and internal carotid arteries in
patients with diabetes and hypertension which were more prominent in the young age group. Values for common carotid IMT
and LD were significantly higher in the left common carotid artery versus the right common carotid artery in both age groups.
Differences between the 2 carotid sides may be attributed to anatomic variations in the common carotid artery origins which
lead to differences in stress between the 2 sides
Age, hypertension, and diabetes can cause significant alterations in arterial structure and function, including changes in lumen diameter (LD), intimal-medial thickness (IMT), flow velocities, and arterial compliance. These are also considered risk markers of atherosclerosis and cerebrovascular disease. A difference between right and left carotid artery blood flow and IMT has been reported by some researchers, and a difference in the incidence of nonlacunar stroke has been reported between the right and left brain hemispheres. The aim of this study was to determine whether there are differences between the right and left common carotid arteries and internal carotid arteries in patient
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