Preferred Language
Articles
/
3xajR4cBVTCNdQwChEBW
Proxy-based sliding mode vibration control with an adaptive approximation compensator for euler-bernoulli smart beams
...Show More Authors

Proxy-based sliding mode control PSMC is an improved version of PID control that combines the features of PID and sliding mode control SMC with continuously dynamic behaviour. However, the stability of the control architecture maybe not well addressed. Consequently, this work is focused on modification of the original version of the proxy-based sliding mode control PSMC by adding an adaptive approximation compensator AAC term for vibration control of an Euler-Bernoulli beam. The role of the AAC term is to compensate for unmodelled dynamics and make the stability proof more easily. The stability of the proposed control algorithm is systematically proved using Lyapunov theory. Multi-modal equation of motion is derived using the Galerkin method. The state variables of the multi-modal equation are expressed in terms of modal amplitudes that should be regulated via the proposed control system. The proposed control structure is implemented on a simply supported beam with two piezo-patches. The simulation experiments are performed using MATLAB/SIMULINK package. The locations of piezo-transducers are optimally placed on the beam. A detailed comparison study is implemented including three scenarios. Scenario 1 includes disturbing the smart beam while no feedback loop is established (open-loop system). In scenario 2, a PD controller is applied on the vibrating beam. Whereas, scenario 3 includes implementation of the PSMC+AAC. For all previously mentioned scenarios, two types of disturbances are applied separately: 1) an impulse force of 1 N peak and 1 s pulse width, and 2) a sinusoidal disturbance with 0.5 N amplitude and 20 Hz frequency. For impulse disturbance signals, the results show the superiority of the PSMC+AAC in comparison with the conventional PD control. Whereas, both the PSMC+ACC and the PD control work well in the case of a sinusoidal disturbance signal and the superiority of the PSMC is not clear.

Crossref
Publication Date
Mon Feb 13 2023
Journal Name
Journal Of Educational And Psychological Researches
Challenges Facing Blended Education from the Point Of View of Teachers Teaching Children with Disabilities
...Show More Authors

The current research aims to identify: 1) the challenges facing blended education from the point of view of teachers of students with disabilities. 2) The challenges facing blended education from the point of view of teachers of students with disabilities according to the gender variable (males-females). 3) The challenges facing blended education from the point of view of teachers of students with disabilities, according to the academic qualifications of graduates

(institute-bachelors-masters). 4) The challenges facing blended education from the point of view of male and female teachers, according to the functional service period with students with disabilities (less than 8 years - from 9 to 15 years - 16 years and above). 5) the

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The relationship between critical thinking, epistemological beliefs, and learning strategies with the students’ academic performance
...Show More Authors

The present study was conducted to investigate the relationship between critical thinking, epistemological beliefs, and learning strategies with the academic performance of high school first-grade male and female students in Yazd. For this purpose, from among all first-grade students, as many as 250 students (130 females and 120 males) were selected by using multistage cluster sampling. The data needed were then collected through using California Critical Thinking Skills Test, Schommer's Epistemological Beliefs Questionnaire, Biggs’ Revised Two Factor Study Process Questionnaire. The findings indicated that there is a positive significant relationship between critical thinking and academic performance and achievement. Moreover, four fa

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Study the Effect of Face Sheets Material on Strength of Sandwich Plates with Circular Hole
...Show More Authors

This study aims to investigate the effect of changing skins material on the strength of sandwich plates with circular hole when subjected to mechanical loads. Theoretical, numerical and experimental analyses are done for sandwich plates with hole and with two face sheet materials. Theoretical analysis is performed by using sandwich plate theory which depends on the first order shear deformation theory for plates subjected to tension and bending separately. Finite element method was used to analyse numerically all cases by ANSYS program.

The sandwich plates were investigated experimentally under bending and buckling load separately. The relationship between stresses and the ratio of hole diameter to plate width (d/b) are built, by

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Mar 30 2023
Journal Name
Al-mustansiriyah Journal Of Science
CA72-4 as a Promising Prognostic and Diagnostic Biomarker in Iraqi Patients with Colorectal Cancer
...Show More Authors

Colorectal cancer (CRC), the second most fatal cancer and the 3rd most common cancer is expected to cause 0.9 million deaths globally in 2025. Carcinoembryonic antigen (CEA) is currently used in the follow-up of patients with colorectal cancer, and in this study, we are trying to find a better marker than CEA in following up on patients' health and knowing the effectiveness of the treatment used and as a diagnostic marker for colorectal cancer. To determine the significance of Cancer antigen 72-4 (CA72-4) as a prognosis predictor in patients with colorectal cancer, compare its prognostic validity to the CEA biomarker. this case-control study includes (150) participants, 100 patients (59 males and 41 females), and 50 healthy controls

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Thu Jul 01 2004
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
THE HAEMOPROTEIDS OF THE AVIAN FAMILY SCOLOPACIDAE IN IRAQ WITH DESCRIPTION OF A NEW SPECIES
...Show More Authors

Three scolopacids out of 150 are found infected with Haemoproteus scolopaci Galli-
Valerio 1929 and H. tringae n. sp. A detailed description of the new taxon is presented along
with a comparison of the diagnostic measurements between the two species.

View Publication Preview PDF
Publication Date
Sun Jan 01 2006
Journal Name
Smj
Treatment of alopecia areata by topical diclofenac sodium gel in comparison with benzoyl peroxide gel
...Show More Authors

KE Sharqie, AA Al-Nuaimy, WJ Kadhum, SMJ, 2006 - Cited by 2

View Publication
Publication Date
Thu Oct 01 2009
Journal Name
Iraqi Journal Of Physics
Gray-Scale Image Brightness/Contrast Enhancement with Multi-Model Histogram linear Contrast Stretching (MMHLCS) method
...Show More Authors

Gray-Scale Image Brightness/Contrast Enhancement with Multi-Model
Histogram linear Contrast Stretching (MMHLCS) method

View Publication Preview PDF
Publication Date
Sun Dec 01 2013
Journal Name
Baghdad Science Journal
Study the Effect of Plant Pathogenic Fungi in solid media in comparison with common Fungicide
...Show More Authors

A study carried out for study effect of furfural that extracted from corn cobs by using specialized reaction system laboratory on phytopathogenic fungi: Pythium aphanidermatum, Rhizoctonia solani, Macrophomina phaseolina and Fusarium solani in addition to biocontrol fungus Trichoderma viride were isolated from infected plants and from their rhizosphere . The preparation results of different concentrations from stock solution in concentration 1% of furflural showed that The concentration was 100 ppm of furfural was inhibited the growth of P. aphanidermatum46.7 % and the was in concentration 400 ppm. while the concentration 500 ppm caused inhibition 50% and 41.1% of R. solani and F. solani respectively. Whereas the concentration 500 pp

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Sep 05 2010
Journal Name
Baghdad Science Journal
Detection of interleukin-6 and interleukin-8 in serum from women with recurrent spontaneous abortion
...Show More Authors

To investigate the role of IL-6 and IL-8 in the immune-regulatory mechanisms involved in the recurrent spontaneous abortion of the first trimester of pregnancy. Serum level of IL-6 and IL-8 were determined in 25 women of age (20-35) years who had a spontaneous abortion of unknown aetiology during the first trimester of pregnancy .They were compared with the corresponding levels of 20 pregnant and non-pregnant women as control groups .cytokine levels were measured by (ELISA) technique .The women with spontaneous abortion had highly significant (P < 0.01) increased serum level of IL-8 and highly significant (P < 0.01 ) decreased level of IL-6 compared to those with normal pregnant and non-pregnant women. The results of this study ma

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
MECHANICAL DEGRADATION OF HIGH MOLECULAR WEIGHT POLYMER WITH SURFACTANT ADDITION IN A ROTATING DISK APPARATUS
...Show More Authors

Mechanical degradation hampers the practical usage of polymers for turbulent drag reduction
application. Mechanical degradation refers to the chemical process in which the activation energy of
polymer chain scission is exceeded by mechanical action on the polymer chain, and bond rupture
occurs. When a water-soluble polymer and surfactant are mixed in water solution, the specific structures
(aggregates) are formed, in which polymer film is formed around micelle. In this work, Xanthan gum (XG) –
Sodium lauryl ether sulfate (SELS) complex formation and its effect on percentage viscosity reduction
(%VR) was studied. It was found that SELS surfactant reduced the mechanical degradation of XG much
more efficiently than th

... Show More
View Publication Preview PDF
Crossref