This study focuses on the modeling of manufactured damper when used in steel buildings. The main aim of the manufactured dampers is to protect the steel buildings from the damaging effects that may result due to earthquakes by introducing an extra damping in addition to the traditional damping.
Only Pure Manufactured Dampers, has been considered in this study. Viscous modeling of damping is generally preferred in structural engineering as it leads to a linear model then it has been used during this study to simulate the behavior of the Pure Manufactured Damper.
After definition of structural parameters of a manufactured damper (its stiffness and its damping) it can be used as a structural element that can be added to a mathematical model of the structure. As the damping of manufactured dampers is generally greater than the damping of traditional materials, then the resulting damping matrix for the whole structure will be classified as a nonclassical damping. As most of literature on earthquake engineering have been written in terms of terminology related to mode superposition method and as this method is applicable to classical damping only. Then, this study tried to check the accuracy of the mode superposition method when applied to a structure with manufactured dampers. In this checking, approximated results of mode superposition method have been compared with more accurate results of direct integration method. From this comparison, it has been noted that the mode superposition method has different levels of accuracy depending on the relation between the fundamental
frequency of the structure and the dominate frequency of the earthmotion. If the frequency of the structure is approaching to a dominate frequency of the earthmotion, then the damping effect will be important and the difference between the direct integration method and the model superposition method is increasing and vice versa
The paper uses the Direct Synthesis (DS) method for tuning the Proportional Integral Derivative (PID) controller for controlling the DC servo motor. Two algorithms are presented for enhancing the performance of the suggested PID controller. These algorithms are Back-Propagation Neural Network and Particle Swarm Optimization (PSO). The performance and characteristics of DC servo motor are explained. The simulation results that obtained by using Matlab program show that the steady state error is eliminated with shorter adjusted time when using these algorithms with PID controller. A comparative between the two algorithms are described in this paper to show their effectiveness, which is found that the PSO algorithm gives be
... Show MoreParasitic diseases including amoebiasis, blastocystosis, giardiasis, trichomoniasis, and schistosomiasis, are all globally wide spread with harmful consequences. The present study was carried out to provide information of the prevalence of these diseases in some regions of Baghdad. Objectives: to detect the prevalence of human pathogenic parasites in some regions of Baghdad in stool samples and urine samples, and to determine the most common age group affected. Methods: Data were collected from Al-Kindy Teaching Hospital and Medical City Teaching Hospital, in the lab of parasitology from November 2018 to May 2019. The present study included (400) sample, which were collected from patients at different ages of both genders, samples of the st
... Show MoreWe used to think of grammar as the bones of the language and vocabulary as the flesh to be added given that language consisted largely of life generated chunks of lexis. This “skeleton image” has been proverbially used to refer to that central feature of lexis named collocation- an idea that for the first 15 years of language study and analysis gave a moment‟s thought to English classroom material and methodology.
The work of John Sinclair, Dave Willis, Ron Carter, Michael McCarthy, Michael Lewis, and many others have all contributed to the way teachers today approach the area of lexis and what it means in the teaching/learning process of the language. This also seems to have incorporated lexical ideas into the teaching mechanis
Background: Melatonin is the main hormone secreted by the pineal gland. This indole compound (N-acetyl-5-methoxytryptamine) is derived from serotonin after two biochemical steps. Melatonin has been implicated in some pharmacological effects including sedative/hypnotic, anticonvulsant activity and others. The aim of this study was to investigate the antinociceptive effect of different doses of melatonin administered i.p. to mice, and then, to find the dose- response line of melatonin in mice as analgesic agent.
Methods: The dose response effect of melatonin (10, 50, and 100mg/kg) were assessed against control using tail flick test in mice as a model of nociceptive pain. In this model, all doses of melatonin were given intraperitoneally
Back ground : Fever is a common medical problem in
children. parents have been shown unrealistic fears of
harmful effects of fever in their children. Resulting in
inappropriate management of fever in their children.
Objective: the objective of this study was to survey
parents about their knowledge andattitude concerning fever
in their children.
Methods : The study involved random selection of
parents who brought their febrile children to emergency
department or out-patient clinics of five teaching and non
teaching hospitals in Baghdad from first of October to end
of December 2002.
Parents of 400 febrile children were interviewed using a
standard questionnaire to obtain sociodemographic
informatio
Back ground : Fever is a common medical problem in children. parents have been shown unrealistic fears of harmful effects of fever in their children. Resulting in inappropriate management of fever in their children. Objective: the objective of this study was to survey parents about their knowledge andattitude concerning fever in their children. Methods : The study involved random selection of parents who brought their febrile children to emergency department or out-patient clinics of five teaching and non teaching hospitals in Baghdad from first of October to end of December 2002. Parents of 400 febrile children were interviewed using a standard questionnaire to obtain sociodemographic information and current knowledge of fever. Results: Ap
... Show MoreMany studies have focused on identifying and classifying freshwater fishes in Iraq, concerned with describing, organizing, and drawing up a list of freshwater fishes in Iraq or the Tigris and Euphrates rivers. Within the most recent updates at the beginning of 2023, 53 native freshwater and 20 exotic (alien or introduced) fish species are recorded and described. This study reviewed the database of morphology and molecular studies of freshwater fish in Iraq and reported species while surveying the fish fauna at different water bodies of the country from 2010 to the beginning of 2023. In conclusion, 29 species (about 40.3%) of all 72 fish species in Iraq still need to be available information on their molecular data.