Preferred Language
Articles
/
alkej-544
Semi-Active Damping of Mechanical Vibrating Systems Using Variable Stiffness Actuator
...Show More Authors

      In this research, a variable stiffness actuator is proposed to enhance the damping of the mechanical vibrating system. The frequency response analysis of the vibrating system is dependant in order to analyze and synthesis this semi-active damping, where the suggested process is using active filter to estimate the present frequency of the vibration system, and this will limit the value of the stiffness of the vibrated system. Two active filter s are needed, low-pass-filter (LPF) to choose the higher stiffness of the actuator at small frequencies as well as more damping and high-pass-filter (HPF) to choose the lower stiffness of the actuator at high frequencies as well as more damping, and so the result will be good damping as a wholre.

      These smart systems and others will increase the importance of the mechatronics systems. This job has a case study to explain the semi-active damping system proposed.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jan 03 2010
Journal Name
Journal Of The Faculty Of Medicine Baghdad
The Effect of Long Term Use of Combined Pills and Depo-Provera on Bone Density Parameters
...Show More Authors

Background: Promotion of bone health is particularly important for young women at reproductive age group, as the critical years for building bone mass are from pre-adolescence to about age 30 years.
patients and Methods: This cross sectional study was performed on three groups, first group of 30 women who had used combined pills for more than 2 years, second group of 30 women who had used Depo-Provera for more than 2 years, last group contain 30 women who had used barrier method or they didn’t use any contraceptive as a control group.Bone mineral density (BMD) of lumbar spine (L2-L4), right proximal femur was determined by dual energy x-ray absorptiometry in (femoral neck, greater trochanter, ward’s t

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 15 2019
Journal Name
Al-khwarizmi Engineering Journal
Experimental and Theoretical Study of the Energy Flow of a Two Stages Four Generators Adsorption Chiller
...Show More Authors

This work is concerned with a two stages four beds adsorption chiller utilizing activated carbon-methanol adsorption pair that operates on six separated processes. The four beds that act as thermal compressors are powered by a low grade thermal energy in the form of hot water at a temperature range of 65 to 83 °C.  As well as, the water pumps and control cycle consume insignificant electrical power. This adsorption chiller consists of three water cycles. The first water cycle is the driven hot water cycle. The second cycle is the cold water cycle to cool the carbon, which adsorbs the methanol. Finally, the chilled water cycle that is used to overcome the building load. The theoretical results showed that average cycle cooling power

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Dec 01 2022
Journal Name
Iraqi Journal Of Physics
Investigation of Radio Frequency Signal Propagation of Wireless Services in Oyo, Oyo State, South Western Nigeria
...Show More Authors

This study reported the investigation of the Radio Frequency (RF) signal propagation of Global System for Mobile Communications (GSM) coverage in Emmanuel Alayande College of Education (EACOED), Oyo, Oyo State, Nigeria. The study aims at amplifying the quality of service and augment end users' sensitivity of the wireless services operation. The drive test method is adopted with estimation of coverage level and received signal strength. The Network Cell Info Lite application installed in three INFINIX GSM mobile phones was employed to take the measurement of the signal strength received from the transmitting stations of different mobile networks. The results of the study revealed that MTN has the maximum signal strength with a mean value

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Sep 30 2023
Journal Name
Journal Of The College Of Education For Women
The Problem of Paradox and its Manifestations: A Study in the Titles of Najm Wali's Novels
...Show More Authors

The irony pushes us to inquire about what is in the text of contradiction, irony, suspense, and other acts of paradox, as well as a departure from what is logical, or familiar, that attracts the attention of the addressee, and this is what drives us to introspect the text and interrogate it in order to get to know the intended product of the text or its real or metaphorical intent. On the other hand, the irony is more in the literary text than in the scientific texts. Therefore, critics add the word literature to it in their definition.

 As it is represented by the paradox, we will seek to study the paradox of the title and the problematic that it may pose as the beginning of the text, and i

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jan 03 2024
Journal Name
Revista Brasileira De Engenharia Agrícola E Ambiental
Effect of cold plasma technique on the quality of stored fruits - A case study on apples
...Show More Authors

The consumption of fresh fruits has increased nowadays due to the lifestyle of the consumers. Maintaining the quality and nutritional value of cut fruits during storage is difficult compared to whole fruits. Deterioration of internal and external quality usually occurs in freshly harvested fruits. It is necessary to use different techniques to maintain the quality and increase the shelf life of the freshly cut product. This research studied the effect of treating apple slices with cold plasma once and with filtered water again on quality characteristics (hardness, moisture content, sugar content, carbohydrate content, and color) after being stored for five days. The best treatment was determined using two different pressures of the plasma j

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Clarivate Crossref
Publication Date
Tue Mar 30 2021
Journal Name
Iraqi Journal Of Science
Effects of Gum Arabic-Coated Magnetite Nanoparticles on the Removal of Pb Ions from Aqueous Solutions
...Show More Authors

To study the removal of lead (Pb) ions from aqueous solutions, novel magnetite nanoparticles (NPs) of Ni0.31Mg0.15Ag0.04Fe2.5O4 were synthesized by coprecipitation synthesis using metal sulfates, and then coated with Gum Arabic (GA). The prepared NPs were analyzed using various spectroscopic and analytical methods, such as X-Ray diffraction analysis (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray spectroscopy (EDX), Fourier Transform Infra-Red spectroscopy (FT-IR), and Atomic Absorption Spectrophotometer (AAS). By using XRD analysis, the cubic inverse spinel structure of the prepared NPs was proven, showing average values of crystallite size, latt

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (5)
Scopus Crossref
Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Physics
The Effect of PVC Powder content on the Elastic Moduli and Acoustic Impedance of Epoxy Composites
...Show More Authors

The primary purpose of the present research was to study the effect of polyvinyl chloride (PVC) powder content on ultrasonic wave velocity in PVC/Epoxy composites. The second part is concerned with the relations of dynamic elastic moduli with the ultrasonic wave velocities, to determine how ultrasonic waves can affect them.
Experimental data have been obtained using the sonic viewer (model -5217 A) device to generate two types of waves, longitudinal waves of frequency 63 kHz and transverse waves of frequency 33 kHz and to measure the transit time required for those waves to travel through individual sample.
The experimental results have shown that the propagation of the ultrasonic velocity increases directly with PVC content in the

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 01 2018
Journal Name
Al Mustansiriyah Journal Of Pharmaceutical Sciences
Effect of Lead Exposure on Some Biochemical Parameter of Battery Factory and Benzene Fuel Stations Workers
...Show More Authors

Publication Date
Mon Aug 01 2022
Journal Name
Biochemical And Cellular Archives
EVALUATION OF THE TOXICITY OF DELTAMETHRIN INSECTICIDE ON SOME HEMATOLOGICAL PARAMETERS AND OXIDATIVE STRESS ON MICE
...Show More Authors

Publication Date
Tue May 01 2012
Journal Name
Arab Journal Of Plant Protection
Influence of Cabbage Aphid Density Brevicoryne brassicae (L.) on the Numerical Response of Chrysoperla carnea (Stephens)
...Show More Authors