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 Dec 10 2019
Journal Name
Biochemical And Cellular Archives
THE EFFECT OF ADDING DIFFERENT LEVELS OF GREEN TEA POWDER (CAMELLIA SINENSIS) TO THE DIET ON PRODUCTIVE PERFORMANCE FOR MEAT BROILERS
...Show More Authors

This study has been carried out in the Station of Poultry Researches which is affiliated to the General Office of Agricultural Researches / Ministry of Agriculture during the period from 01/04/2018 to 14/05/2018 there are 300 one day old chick of type (Ross 308) used in this study, and has been fed on diets which green tea powder (Camellia sinensis) has been added to it with the levels 0.5 , 1 , 1.5 , 2 g/kg as a feed for the treatments T 2 , T 3 , T 4 and T 5 respectively and compared to the control treatment T 1 which is devoid of addition, every treatment included three replicates each one has 20 birds in order to study the effect of adding a various levels of green tea powder (Camellia sinensis) to the diet on the productive performance

... Show More
Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Educational And Psychological Researches
Positive thinking and its relation to self academic motivation and the trend towards teaching profession among the students of education colleges
...Show More Authors

The research aims to know the relation between positive thinking and self academic motivation, trend towards teaching profession. So a sample of (344) male and female student of the morning study of education colleges from the two universities of Baghdad and al Mustansria for the academic year 2012-2013.

So three tools had been used to achieve the procedures of the research which are: the scale of positive thinking constracted by Abdal satar Ibrahim year 2010, the scale of self academicmotivation constracted by (Gottfried) and adapted by Hanan Hussan year 2010, the scale of teaching profession trend constracted by Enayat Zaki year 1974.

And by using the statistical means of person

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
Journal Of The Mechanical Behavior Of Materials
Investigation of the performance of integrated intelligent models to predict the roughness of Ti6Al4V end-milled surface with uncoated cutting tool
...Show More Authors
Abstract<p>Titanium alloys are broadly used in the medical and aerospace sectors. However, they are categorized within the hard-to-machine alloys ascribed to their higher chemical reactivity and lower thermal conductivity. This aim of this research was to study the impact of the dry-end-milling process with an uncoated tool on the produced surface roughness of Ti6Al4V alloy. This research aims to study the impact of the dry-end milling process with an uncoated tool on the produced surface roughness of Ti6Al4V alloy. Also, it seeks to develop a new hybrid neural model based on the training back propagation neural network (BPNN) with swarm optimization-gravitation search hybrid algorithms (PSO-GS</p> ... Show More
View Publication
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Sun Feb 03 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Effect of The Mental image Building Dimensions for The Company to Aattract Attention of Iraqi Consumers for local Products: Exploratory Study
...Show More Authors

The survey showed sample opinions of officials in the general company for vegetable oils industry, and the statement of the order of the effect of these dimensions depending on the degree of importance, the questionnaire was used as a key tool in collecting data and information of the sample consisted of 30 officials, arithmetic mean, standard deviation, percentages, Spearman correlation coefficient and the global statistical analysis as a statistical methods that based on statistical program (SPSS), The researcher came to several conclusions, most important that there is high agreement by the respondents of the importance of the dimensions of building a mental picture of the company and to attract the consumer's attention, Also research

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jun 03 2017
Journal Name
International Journal Of Science And Research
The Sealing Ability of New Bioceramic Material Used to Repair Furcal Perforation Compared with the Traditional Repair Materials: UV Spectrophotometer Analysis
...Show More Authors

Abstract: Iatrogenic furcal root perforations are serious complications during dental treatment. This study was aimed to compare the sealing ability of new bioceramic root repair material TotalFill® with the other perforation repair materials (GIC, MTA and Biodentine) using a dye- extraction method.Materials and Methods: Forty extracted, human mandibular molars with non-fused well developed root were collected. Artificial perforations were made from the external surface of the teeth. Then the teeth were randomly divided into 4 experimental groups (n= 10) according to the type of repair material used in this study; Medifil glass ionomercement, TotalFill® bioceramic root repair material, BiodentineTM and MTA Plus. The specimens were then im

... Show More
Preview PDF
Publication Date
Thu Nov 13 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of the addition of silanated poly propylene fiber to polymethylmethacrylate denture base material on some of its mechanical properties
...Show More Authors

Background: Poly propylene fibers with and without silane treatment have been used to reinforce heat cure denture base acrylic but, some mechanical properties like transverse strength, impact strength, tensile strength, hardness, wear resistance and wettability. Which are related to the clinical use of the prosthesis are not evaluated yet. The aim of the study is to identify the influence of incorporation of treated and untreated fibers on these properties Materials and methods: Eighty four heat cure acrylic specimens were constructed by conventional flasking technique. They were divided into six groups according to the tests and each group was subdivided into two subgroups control and experimental groups (seven samples for each subgroup

... Show More
View Publication Preview PDF
Publication Date
Thu Nov 13 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of small cardamom extracts on Mutans streptococci in comparison to chlorhexidine gluconate and de-ionized water (In vitro study (
...Show More Authors

Background: Herbs are being widely explored to discover alternatives to synthetic antibacterial agents.Small Cardamom often referred to as queen of spices because of its very pleasant aroma and taste, have a history as old as human race. Most people use cardamom as a spice and are largely unaware of its numerous health benefits. The purpose of this study was to evaluate the effect of different concentrations of water and alcoholic cardamom extracts on sensitivities, growth, and adherence of Mutans streptococci in vitro. Materials and Methods: In this study, saliva was collected from ten volunteers (College students 18-22 years). Agar well technique was used to study the sensitivities of Mutans streptococci to different concentrations of s

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of Black Cardamom Extracts on Mutans Streptococci in Comparison to Chlorhexidine Gluconate and De-ionized Water (In Vitro Study)
...Show More Authors

Background: Spices and herbs have been used by many cultures to enhance the flavor and aroma of food and for their medicinal value. Black cardamom is one of these spices widely used in cooking because of its unique taste and powerful flavor. The aim of study was to test the effect of black cardamom on Mutans Streptococci in comparison to chlorhexidine gluconate (0.2%) and de-ionized water. Materials and methods: Dried fruits of black cardamom were extracted by using alcohol (70% ethanol). Saliva was collected from seven volunteers. Agar well technique with different concentrations of black cardamom extracts was used to test the sensitivities of Mutans Streptococci, as well black cardamom extracts effect on viable counts of Mutans Streptococ

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Nov 13 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Nasopharyngeal Dimensions in Relation to Some Dento-Cranial Variables in Class I and II Skeletal Patterns (A Comparative Cephalometric Study)
...Show More Authors

Background: The size of the nasopharyngeal airway was believed to have an important role in the development of the dentofacial structure. This study was carried out to test the relation between the nasopharyngeal dimensions with some dento-cranial measurements in class I and II jaw relationship. Materials and Methods: This study was done on 60 subjects (30 males and 30 females) at age range 18-25 years. Cephalometric radiograph has been taken to each subject and the measurements were recorded. The sample was divided into two groups, class I skeletal relationship (15 males and 15 females) and class II skeletal relationship (15 males and 15 females). Comparisons between the different study groups were undertaken. Results: In class I skeletal

... Show More
View Publication Preview PDF
Publication Date
Thu Nov 13 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Assessment of serum levels of MMP-8 and hs CRP in chronic periodontitis patients in relation to atherosclerotic cardiovascular disease
...Show More Authors

Background: Periodontitis and Atherosclerosis Cardiovascular disease are chronic inflammatory diseases which are highly prevalent. During the last two decades, there has been an increasing interest in the impact of oral health on atherosclerosis and subsequent cardiovascular disease.Aims of the study wereto evaluate the periodontal health status in study groups (Atherosclerotic cardiovascular disease patients with chronic periodontitis and patients having chronic periodontitis),to estimate the serum levels of Matrixmetalloproteinase-8(MMP-8) and high sensitive C-reactive protein(hs CRP) in study and control groups and compare between them. Also,test the correlation between the serum levels of MMP-8 and hs CRP with clinical periodontal par

... Show More
View Publication Preview PDF