The present work covers the analytical design process of three dimensional (3-D) hip joint prosthesis with numerical fatigue stress analysis. The analytical generation equations describing the different stem constructive parts (ball, neck, tour, cone, lower ball) have been presented to reform the stem model in a mathematical feature. The generated surface has been introduced to FE solver (Ansys version 11) in order to simulate the induced dynamic stresses and investigate the effect of every design parameter (ball radius, angle of neck, radius of neck, neck ratio, main tour radius, and outer tour radius) on the max. equivalent stresses for hip prosthesis made from titanium alloy. The dynamic loading case has been studied to a stumbling case. The load has been applied on the cap tip as a concentrated load distributed on the interface of ball and socket. The results show that the decreasing of max. Fatigue stress by (175) MPa could be obtained by increasing the outer tour radius from (10)mm to (15) mm and that will change the max. Fatigue zone location from the tour section to the neck. The ball radius and neck angle must be as lower as possible to decrease the fatigue stresses. The most dominate parameter to increase the safety factor is the radius of neck.
This paper features the modeling and design of a pole placement and output Feedback control technique for the Active Vibration Control (AVC) of a smart flexible cantilever beam for a Single Input Single Output (SISO) case. Measurements and actuation actions done by using patches of piezoelectric layer, it is bonded to the master structure as sensor/actuator at a certain position of the cantilever beam.
The smart structure is modeled based on the concept of piezoelectric theory, Bernoulli -Euler beam theory, using Finite Element Method (FEM) and the state space techniques. The number of modes is reduced using the controllability and observability grammians retaining the first three
dominant vibratory modes, and for the reduced syste
This study focuses on CFD analysis in the field of the shell and double concentric tube heat exchanger. A commercial CFD package was used to resolve the flow and temperature fields inside the shell and tubes of the heat exchanger used. Simulations by CFD are performed for the single shell and double concentric tube.
This heat exchanger included 16 tubes and 20 baffles. The shell had a length of 1.18 m and its diameter was 220 mm. Solid Works 2014, ANSYS 15.0 software was used to analyze the fields of flow and temperature inside the shell and the tubes. The RNG k-ε model was used and it provided good results. Coarse and fine meshes were investigated, showing that aspect ratio has no significant effect. 14 million
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The article critically analyzes traditional translation models. The most influential models of translation in the second half of the 20th century have been mentioned, among which the theory of formal and dynamic equivalence, the theory of regular correspondences, informative, situational-denotative, functional-pragmatic theory of communication levels have been considered. The selected models have been analyzed from the point of view of the universality of their use for different types and types of translation, as well as the ability to comprehend the deep links established between the original and the translation.
Аннотация
It was confirmed in this research that the ligand calcichrome formed stable complex with calcium ion at pH of 8.5 which verified by UV/Vis and FTIR spectral analysis and the complexation occurred via hydroxyl groups .
The stoichiometric ratio of the formed complex was found to be 1:1 by mole ratio and continuous variation methods . Dry ashing method of the complex and flame emission photometric analysis offered a calcium percentage in calcium complex equal 4.5% with an error of 2.41% due to experimental errors .
This paper deals with the role of the clergy in the Church and artists in the emergence of this art, which is represented by an atmosphere of spiritual, aesthetic, artistic, technical and engineering very magnificence and is located in two Find.Chapter One: the stages of stained glass in the Middle AgesThe Architects Goths to get rid of the walls gradually, based Baloctav plane, columns and beams strengthened with the vehicle, as previously mentioned, making the building looks like a glass of excessive use of colored windows building, this art has been known to the art of stained glass And the second chapter: the stages of stained glass in the Middle Ages Department of Winston (Winston) works of stained glass since its inception in the t
... Show MoreBackground: The hippocampus is empirically assumed to have different functions, of which the best known are: the representation of self-location in cognitive dimensions, and the storage and retrieval of memory.
Materials and methods: Eleven adult male albino rats were used. Brain specimens were processed into paraffin blocks, sectioned (10 μm thick), and stained using Haematoxylin and Eosin, and Luxol Fast Blue MBS counterstained with Cresyl Violet. Morphometric analysis was done through eyepiece micrometers.
Results: The lamellae of the hippocampus were morphometrically evaluated in context of embryogenesis and nerve fiber content.
Conclusion: This study confirmed the existence of differences in nerve
Background: Several factors render chronic lymphocytic leukemia (CLL) an interesting subject for study by researchers. These include marked progress in understanding the molecular biology of normal and neoplastic lymphocytes and recent advances in molecular genetics techniques. Among molecular markers, matrix metalloproteinase-9 (MMP-9), have been widely studied.
Objectives: The aim of the study is to evaluate the role of MMP-9 in the pathogenesis of CLL and to assess its prognostic role.
Patients and methods: A retrospective cross-sectional study done on 60 patients with chronic lymphocytic leukemia compared with 20 controls (anemic patients), all recruited at the Medical City Teaching Hospital laboratories from January 2004 to De
The paper presents mainly the dynamic response of an angle ply composite laminated plates subjected to thermo-mechanical loading. The response are analyzed by analytically using Newmark direct integration method with Navier solution, numerically by ANSYS. The experimental investigation is to fabricate the laminates and to find mechanical and thermal properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus, longitudinal and transverse thermal expansion. Present of temperature could increase dynamic response of plate also depending on lamination angle, type of mechanical load and the value of temperature.