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Semi-Active Damping of Mechanical Vibrating Systems Using Variable Stiffness Actuator
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      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.

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Publication Date
Wed Dec 01 2021
Journal Name
Baghdad Science Journal
Improvement of the Fault Tolerance in IoT Based Positioning Systems by Applying for Redundancy in the Controller Layer
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In recent years, the positioning applications of Internet-of-Things (IoT) based systems have grown increasingly popular, and are found to be useful in tracking the daily activities of children, the elderly and vehicle tracking. It can be argued that the data obtained from GPS based systems may contain error, hence taking these factors into account, the proposed method for this study is based on the application of IoT-based positioning and the replacement of using IoT instead of GPS.  This cannot, however, be a reason for not using the GPS, and in order to enhance the reliability, a parallel combination of the modern system and traditional methods simultaneously can be applied. Although GPS signals can only be accessed in open spaces, GP

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Publication Date
Wed Jan 01 2020
Journal Name
Karbala Journal Of Physical Education Sciences
The effect of using a designed device to develop the technical performance of the descending landing skill facing with half a cycle on the parallel device of the technical men's
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The research included five sections containing the first section on the introduction of the research and its importance and was addressed to the importance of the game of gymnastic and skilled parallel effectiveness and the importance of learning, but the problem of research that there is a difference in learning this skill and difficulty in learning may be one of the most important reasons are fear and fear of falling and injury, And a lack of sense of the movement of the movement is one of the obstacles in the completion of the skill and the goal of research to design a device that helps in learning the skill of descending Almtor facing with half a cycle according to the typical locomotor track on the parallel device of the technical men'

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Publication Date
Wed Dec 15 2010
Journal Name
Iraqi Journal Of Laser
Photodynamic Inactivation of Candida Albicans Sensitized by Malachite Green
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The aim of this study is to investigate the ability of malachite green (MG) combined with 650nm diode laser to kill Candida albicans and to spectrally study the MG photodegradation after photodynamic therapy (PDT) spectrally. Cultures of Candida albicans were exposed to 40mW, 650 nm diode laser in the absence of MG. In PDT group, the MG was added to the Candida suspension for 5 min then exposed to diode laser for (5, 10, 15, 20) min at power density of 0.59W/cm2. The absorption spectrum of the photosensitized fungal suspension was obtained. The data were submitted to T-test (p<0.05). A 650nm diode laser in the presence of MG reduced the number of CFU/ml in 98.4%. Laser with 650nm alone and MG alone did not reduce significantly the num

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
INFLUENCE OF AMBIENT TEMPERATURE ON STIFFNESS OF ASPHALT PAVING MATERIALS
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Asphalt pavement properties in Iraq are highly affected by elevated summer air temperatures. One of these properties is stiffness (resilient modulus). To explain the effect of air temperatures on stiffness of asphalt concrete, it is necessary to determine the distribution of temperatures through the pavement asphalt concrete layers. In this study, the distribution of pavement temperatures at three depths (2cm,7cm, 10cm) below the pavement surface is determined by using the temperature data logger instrument. A relationship for determining pavement temperature as related to depth and air temperature has been suggested. To achieve the objective of this thesis, the prepared specimens have been tested for indirect tension in accordance with

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Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of the Shapiro-Wilk test Jureckova test using simulation and multiple distributions
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 إن المقصود باختبارات حسن المطابقة هو التحقق من فرضية العدم القائمة على تطابق مشاهدات أية عينة تحت الدراسة لتوزيع احتمالي معين وترد مثل هكذا حالات في التطبيق العملي بكثرة وفي كافة المجالات وعلى الأخص بحوث علم الوراثة والبحوث الطبية والبحوث الحياتية ,عندما اقترح كلا من   Shapiro والعالم Wilk  عام 1965 اختبار حسن المطابقة الحدسي مع معالم القياس
(

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Publication Date
Wed Sep 01 2021
Journal Name
Journal Of Engineering
Thermal Buckling of Laminated Composite Plates Using a Simple Four Variable Plate Theory
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In this study, the thermal buckling behavior of composite laminate plates cross-ply and angle-ply all edged simply supported subjected to a uniform temperature field is investigated, using a simple trigonometric shear deformation theory. Four unknown variables are involved in the theory, and satisfied the zero traction boundary condition on the surface without using shear correction factors, Hamilton's principle is used to derive equations of  motion depending on a Simple Four Variable Plate Theory for cross-ply and angle-ply, and then solved through Navier's double trigonometric sequence, to obtain critical buckling temperature for laminated composite plates. Effect of changing some design parameters such as, ortho

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Publication Date
Thu Sep 08 2022
Journal Name
Mathematical Statistician And Engineering Applications
δ-Semi Normal and δ-Semi Compact Spaces
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In this paper by using δ-semi.open sets we introduced the concept of weakly δ-semi.normal and δ-semi.normal spaces . Many properties and results were investigated and studied. Also we present the notion of δ- semi.compact spaces and we were able to compare with it δ-semi.regular spaces

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Physics
Short-term effect of ultrasound therapy on stiffness elbow joint
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Elbow stiffness is hard to treat and commonly resulted from trauma or degenerative arthritis. This study aimed to demonstrate the effectiveness of using ultrasound therapy in management of stiff elbow joint resulted from several etiological factors. A total number of 42 patients (35 male and 7 female) allocated randomly from the Department of Physiotherapy at Al-yarmouk Teaching Hospital during 2013. Each patient examined physically by physiotherapist taking in consideration the measurement of the joint movement angle using goniometer in flexion and the extension, and the pain score using visual analogue scale (VAS). Ultrasound therapy initiated thrice weekly for two weeks. At the time of entry, the means degree of flexion and extension

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Publication Date
Thu Jun 16 2022
Journal Name
Al-khwarizmi Engineering Journal
Intelligent Tuning Control of two Link Flexible Manipulator with Piezoelectric Actuator
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This paper represents an experimental study on the application of smart control represented by the use of the fuzzy logic controller. Two-link flexible manipulators that are used in airspace and military applications are made of flexible materials characterized by low frequency and damping ratio. To solve this problem, this paper proposes the use of smart materials (piezoelectric transducers), where each link is bonded with a pair of piezoelectric transducers that act as a sensor and another as an actuator. As the arm vibrates because of the movement generated by the motor, this voltage is controlled by a regulator inside the LABVIEW® 2020 software and sends the output control voltage to the piezoelectric actuator. Experimental results

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Publication Date
Fri Sep 01 2023
Journal Name
Iraqi Journal Of Physics
Influence of NiTi Spring Dimensions and Temperature on the Actuator Properties
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Nitinol (NiTi) is used in many medical applications, including hard tissue replacements, because of its suitable characteristics, including a close elastic modulus to that of bones. Due to the great importance of the mechanical properties of this material in tissue replacements, this work aims to study the hysteresis response in an attempt to explore the ability of the material to remember its previous mechanical state in addition to its ability to withstand stress and to obtain the optimal dimensions and specifications for the manufacturer of NiTi actuators. Stress-strain examination is done in a computational way using a mutable Lagoudas MATLAB code for various coil radii, environment temperatures, and coil lengths. The computational m

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