Preferred Language
Articles
/
9Rc5e44BVTCNdQwCC0lc
Inducing Frictional Force to Enhance the Transient Response in Beams
...Show More Authors

This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jan 01 2013
Journal Name
International Journal Of Contemporary Mathematical Sciences
Equivalent between the Criterion and the Three Open Set's Conditions in Disk-Cyclicity
...Show More Authors

A vector in a separable infinite dimensional Hilbert space is called disk-cyclic for bounded operator if the orbit α : 0, α∈;|∝| 1is dense in. The useful tool used to discover codisk-cyclic operation is called the disk-cyclic Criterion. In this paper we will show that some equivalent conditions of the

View Publication
Crossref
Publication Date
Tue Apr 19 2022
Journal Name
Ishraqat Tanmawia
The reality of the divorce problem in Iraqi society Reasons, solutions and results
...Show More Authors

Praise be to God, who created people from one soul, and made her husband, and prayers and peace be upon His Messenger, Mercy given and the grace given, and on a machine and companions pure. Divorce cases have increased in recent years in a worrying manner, especially since divorce has unforeseen consequences at the individual and social levels. The source of concern stems from the fact that the cohesion and integrity of society starts from a family as it is the cornerstone of the social structure, which is the foundation upon which the large society is based. Marital life may suffer from problems and obstacles that are difficult to solve, so the man presents the divorce of his wife and that the phenomenon of divorce is not a result of it, b

... Show More
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Study the Characteristic of the Coupling Parameter ( ? ) in Dusty Plasma by Computer modeling
...Show More Authors

Computer modeling has been used to investing the Coulomb coupling parameter ?. The effects of the structure parameter K, grain charge Z, plasma density N, temperature dust grain Td, on the Coulomb coupling parameter had been studied. It was seen that the ? was increasing with increasing Z and N, and decrease with increasing K and T. Also the critical value of ? that the phase transfer of the plasma state from liquid to solid was studied.

View Publication Preview PDF
Crossref
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The Chronic Effects of Salinity in the Biology of ?? Rotifers Brachionus calyciflorus Pallas
...Show More Authors

The present study included the effect of chronic exposure for two concentrations of NaC? salt on the biology of fresh water zooplankton species Brachionus calyciflorus (from ^otifera). The concentrations 0.5 , 0.75%o were used for chronic exposure to investigate its effects on the life tables, range of the rate of expectation for further life and reproduction. The rotifer B. calyciflorus was sensitive to salinity and may tried to protect the species by increasing the size (2.22 ind./clutch lor control group and 2.9? for 0.5%o concentration) and number of clutches produced ?.1? clutch/female for control group and 2.9 ' ' ' for 0.75 %0 concentration) beside stimulation the animal to produce the first clutch of eggs earlier? ? small reduction

... Show More
View Publication Preview PDF
Publication Date
Mon Oct 31 2022
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
The adoption of green management in Iraqi construction industry: The challenges and benefits
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Mon Jul 01 2019
Journal Name
Iop Conference Series: Materials Science And Engineering
Characteristic Zero Resolution of Weyl Module in the Case of the Partition (8,7,3)
...Show More Authors
Abstract<p>In this paper, we studied the resolution of Weyl module for characteristic zero in the case of partition (8,7,3) by using mapping Cone which enables us to get the results without depended on the resolution of Weyl module for characteristic free for the same partition.</p>
View Publication
Scopus (16)
Crossref (2)
Scopus Crossref
Publication Date
Thu Sep 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Analyzing the relationship between stock market volatility and economic activity in the USA
...Show More Authors

This study examines the dynamic relationship between stock market and economic activity in the United States to verify the possibility of using financial indicators to monitor the turning points in the expected path of future economic activity. Has been used methodology (Johansen - Juselius) for the Co-integration and causal (Granger) to test the relationship between the (S & P 500 , DJ) index  and gross domestic product (GDP) in the United States for the period
(1960-2009). The results of the analysis revealed the existence of a causal relationship duplex (two-way) between the variables mentioned. which means the possibility of the use stock market indicators to pre

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jan 01 2020
Journal Name
International Journal Of Psychosocial Rehabilitation
The problems faced by First-grade intermediate students in studying the Arabic language
...Show More Authors

This study investigates the challenges encountered by first-grade intermediate students in learning the Arabic language. It aims to identify specific obstacles that hinder language acquisition and proficiency among this demographic. Through qualitative and quantitative methods, including surveys and interviews with students, teachers, and parents, the research highlights key issues such as limited vocabulary, difficulties in grammar, lack of engagement with the material, and inadequate teaching resources. The findings reveal a complex interplay between cognitive, social, and educational factors that contribute to these challenges. The study underscores the need for targeted interventions, such as enhanced pedagogical strategies and improved

... Show More
Preview PDF
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Enrichment Programs on the Performance of Gifted Students in KSA
...Show More Authors

       The current study aimed at identifying the impact of each of the full and part time summer enrichment programs on the performance of gifted students. Moreover, it aimed to study the difference between the full and part time programs on the performance of gifted students. The study sample consisted of (115) students from the full time programs and (137) students from the part time programs, they have been randomly selected from the gifted students participating in the full and part time summer enrichment programs. The researcher used the scale of student performance. The results indicated that there were statistically significant differences between the averages of the pre and post applications of the

... Show More
View Publication Preview PDF
Publication Date
Mon Mar 15 2021
Journal Name
Al-academy
The effectiveness of media communication and its problems in the contemporary theatrical presentation
...Show More Authors

View Publication
Crossref