The importance of vibrations in rotating rotors in engineering applications has been examined, as has the best approach to interpreting vibration data. The most extensively used analytical approaches for rotating shaft vibration analysis have been investigated. In this research, a detailed study was made of the Rayleigh and Dunkerley methods due to their importance in the special calculations to find the amplitude of vibrations in the rotation system. The multi-node method was used to calculate both Dunkerley's and Rayleigh's methods. An experimental platform was built to study the vibrations that occur in the rotating shafts, and the results were compared with theoretical calculations and with different distances of the bearings. It proved that there is very little error between the experimental and theoretical results. The vibration signal from the sensors was analyzed using the LABVIEW program. Rayleigh's method was compared to the exact method, and it was considered the most accurate method. It was found that it made very little difference, up to about 0.06%. As for the Dunkerley method, the difference between it and the proper method is about 4%, which is acceptable. Then a comparison was made between Rayleigh's and Dunkerley's methods, and it was found that Dunkerley's method is the most appropriate in the calculations.
Abstract Background: One of the most important methods to replace lost teeth is dental implants. In order to increase the strength of connection of the implant with the jaw bone to provide early loading after placement, implant is coated by different coating materials that achieved that purpose. The aim of this study was to evaluate the influence of coating CP Ti implant with calcium carbonate on the strength of bone-implant interface after two and six weeks of implantation in rabbit femur bone by torque removal test, histological and histomorphometric analysis. Materials and methods: Coating the surface of commercially pure titanium screws with extra pure synthetic calcium carbonate via electrophoretic deposition method (EPD) was done. The
... Show MoreThe effect of the tensor term in the Skyrme interaction has been estimated in calculating the static and dynamic nuclear properties in sd and fp-shell model spaces nuclei. The nuclear shell gaps have been studied with different Skyrme parameterizations; Skxta and Skxtb with tensor interaction, SkX, SkM, and SLy4 without tensor interaction, and Skxcsb with consideration of the effect of charge symmetry breaking. We have examined the stability of N = 28 for 42Si and 48Ca. The results showed that the disappearance of the magicity occurs in the shell closure of 42Si. Furthermore, excitation energy, quadrupole deformation, neutron separation energy, pairing energy, and density profile have also been calculated. Quadrupole deformation indicates a
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Praise be to Allah, the Lord of the Worlds, the best prayer and the best prayer, on our master Muhammad, and on his pure God, and his companions and the faithful, and who followed them by charity to the day of religion. This relationship between emphasis, is a sincere, and this harmony, such as the relationship between water, and the green, but it is good, but, with greenery, it is better, and as well as alone, is a beautiful view, but the most beautiful, with the most beautiful. From here he was starting on myself in writing the fundamentalist research of jurisprudence, to show the depth of this interconnection. The doctrine as a new term, then the taj al-Din al-Suobki came after three centuries, and a
... Show MoreThe manifestations of climate change are increasing with the days: sudden rains and floods, lakes that evaporate, rivers that experience unprecedentedly low water levels, and successive droughts such as the Tigris, Euphrates, Rhine, and Lape rivers. At the same time, energy consumption is increasing, and there is no way to stop the warming of the Earth's atmosphere despite the many conferences and growing interest in environmental problems. An aspect that has not received sufficient attention is the tremendous heat produced by human activities. This work links four elements in the built environment that are known for their high energy consumption (houses, supermarkets, greenhouses, and asphalt roads) according t
... Show MoreThe study of the subject shows us the couflict between Somalian- Ethiopian. About Al-Oaghaden (1960-1978). This province is purely Somalian area in their language ،manners ،
traditions ،and their most population from Migrant bedouin.
In the last nineteenth century ،Ethiopia had entered to exit from plateau ،and become nearly from Red Sea and Indian Ocean.
The study shows us ،the conflict between colonization countries ،about African horn ،then fore Ethiopia entered as partner to divide the zone area ، and that division hadn’t Cares about the unity of people ،or the similar of language or religoun ،for this reason which had interference happened between broders and division about the same tribe from more Century ،
The current study aims to examine the experience of female students with disabilities who studying in university in kingdom of Saudi Arabia. To this end, the researcher used semi-structured interview as an instrument to collect the study data which regards as one of the descriptive approach tools. The sample comprised (12) disabled-female students from multidiscipline within both college of arts and college of education. To analyze the collected data, the author utilized a thematic analysis method following six steps as stated by (Braun and Clark, 2006). The findings revealed that disabled students have a high self-confidence which push them forward to take part in activities that hold on campus. Besides, significant variation were shown
... Show MoreMoney laundering is consider a crime in legal perspective and aphenomenon of negative effects in economic and Social perspective for thevarious countries of the world by the diversity of their economies to make thebadly damaged in the banking service and its reputation in some cases may leadto bankruptcy of banks, and the fact that banks is one of the most importantcircles that revolve the illicit funds, Due to its branched the banking operations,speed and overlap and increase it's complicated with the progress of bankingoperations and the use of electronic services modern here's challenges atvarious levels between the application of the legislation to combat moneylaundering and between actual fact it must find ways and means of legislat
... Show Moremethodology six sigma Help to reduce defects by solving problems effectively, and works Lean to reduce losses through the flow of the manufacturing process and when integrating these two methodologies (Lean and six sigma), the methodology of Lean six sigma will form the entrance to the organizers of the optimization process and increase the quality and reduce lead times and costs . by focusing on the needs of the customer. this process uses statistical tools and techniques to analyze and improve processes.
We have conducted this research in the General Company for Electrical Industries and adopted its product (machine cooling water three taps) as a sample for research. In order to determine t
... Show MoreThis study calculated the surface roughness length (Zo), zero-displacement length (Zd) and height of the roughness elements (ZH) using GIS applications. The practical benefit of this study is to classify the development of Baghdad, choose the appropriate places for installing wind turbines, improve urban planning, find rates of turbulence, pollution and others. The surface roughness length (Zo) of Baghdad city was estimated based on the data of the wind speed obtained from an automatic weather station installed at Al-Mustansiriyah University, the data of the satellite images digital elevation model (DEM), and the digital surface model (DSM), utilizing Remote Sensing Techniques. The study area w
... Show MoreA stylistic study in the poetry of Hafiz Ibrahim, praise be to God, Lord of the worlds, and prayers and peace be upon his best messengers, and the seal of his prophets, Muhammad and his good and pure family, and after ...
The poet Hafez Ibrahim is considered one of the well-known poets in the modern era, and his language was distinguished by sobriety, eloquence in expressions, and beautiful meanings And he had my journey in the study of his poetry a stylistic study, and the research came with an introduction in which the concept of stylistics was briefly explained, since it was studied by many researchers, then divided the research into three topics: I studied in the first the construction of the poem, and I stood at the most importan