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Stress Analysis of Guide Rails of Elevators
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The mechanical design of elevator elements is always performed by international standards. The engineer selects the appropriate elements of elevator according to catalogues without knowing scientific details. Therefore, a theoretical analysis is achieved at two operating conditions for guide rails (1) safety gear operation, and (2) running condition with the loads unevenly distributed on the elevator car. The guide rail is considered a continuous beam with variable supports. Then the British code is listed showing the equations used in it.

The theoretical equations showed that guide rails are never subjected to stress in simultaneous combined buckling and bending in the plane, where the bending moment is exerted. It is always a combination of pressure and bending. Consequently, it is wrong to consider a simultaneous effect of buckling and bending. The equations in the catalogues oppose the theoretical results concerning buckling of guide rails. Therefore, a recommended calculation method for guide rails is presented to be an acceptable method for analysis of guide rail.

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Publication Date
Mon Dec 24 2018
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
REVISION OF THE FAMILY CHLOROPIDAE (DIPTERA) IN IRAQ
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    The aim of this study is to survey and make to revision the genera and species of Chloropidae fauna of Iraq. The investigation showed four species belonging four genera, which belongs to two subfamilies, and one unidentified species belonging to the genus Elachiptera Maquart, The specimens were compared with stored insects at Department of Entomology and invertebrates, Iraq Natural History Research Center and Museum.

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Publication Date
Tue Dec 26 2017
Journal Name
Al-khwarizmi Engineering Journal
Optimization of Wear Parameters in AISI 4340 Steel
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Abstract

 This study investigated the optimization of wear behavior of AISI 4340 steel based on the Taguchi method under various testing conditions. In this paper, a neural network and the Taguchi design method have been implemented for minimizing the wear rate in 4340 steel. A back-propagation neural network (BPNN) was developed to predict the wear rate. In the development of a predictive model, wear parameters like sliding speed, applying load and sliding distance were considered as the input model variables of the AISI 4340 steel. An analysis of variance (ANOVA) was used to determine the significant parameter affecting the wear rate. Finally, the Taguchi approach was applied to determine

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Publication Date
Wed Jul 29 2020
Journal Name
Iraqi Journal Of Science
Some Chaotic Properties of G- Average Shadowing Property
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 Let  be a metric space and  be a continuous map. The notion of the  -average shadowing property ( ASP )  for a continuous map on  â€“space is introduced  and the relation between the ASP and average shadowing property(ASP)is investigated. We show that if  has ASP, then   has ASP for every . We prove that if a map  be pseudo-equivariant with dense set of periodic points and has the ASP,  then  is weakly mixing. We also show that if   is a expansive pseudo-equivariant homeomorphism that has the ASP and  is topologically mixing,  then  has a  -specification. We obtained that the identity map  on  has the ASP  if and only if th

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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
Strategies of Understanding Written Texts in EFL Classrooms
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Reading strategies are of interest for what they reveal about the ways readers manage their interaction with written texts and how these strategies are related to text understanding, acquisition ,storage ,and retrieval of information .In EFL comprehension lessons, the students try to work out interpretations of the meaning related to the written word through the usage of different comprehension strategies. Yet, there are moments where the participants in the classroom fail to reach a successful understanding of the passage read despite the guidance of the teacher. The present research aims at investigating and identifying moments of comprehension failure and reasons behind them .It also aims at specifying the different strategies used in

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Publication Date
Thu May 04 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Degree of Monotone Approximation in , p Lα Spaces
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The aim of this paper is to study the best approximation of unbounded functions in the
weighted spaces
,
1, 0 ,
p
p L α
α ≥>.
Key Words: Weighted space, unbounded functions, monotone approximation

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Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
The Realization of positive politeness strategies in language
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0

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Publication Date
Thu Sep 30 2021
Journal Name
Iraqi Journal Of Science
The Dynamics of Biological Models with Optimal Harvesting
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      This paper aims to introduce a concept of an equilibrium point of a dynamical system which will call it almost global asymptotically stable. We also propose and analyze a prey-predator model with a suggested  function growth in prey species. Firstly the existence and local stability of all its equilibria are studied. After that the model is extended to an optimal control problem to obtain an optimal harvesting strategy. The discrete time version of Pontryagin's maximum principle is applied to solve the optimality problem. The characterization of the optimal harvesting variable and the adjoint variables are derived. Finally these theoretical results are demonstrated with numerical simulations.

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Publication Date
Sun Aug 01 2021
Journal Name
International Journal Of Mechanical Engineering And Robotics Research
International Journal of Mechanical Engineering and Robotics Research
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This paper proposes feedback linearization control (FBLC) based on function approximation technique (FAT) to regulate the vibrational motion of a smart thin plate considering the effect of axial stretching. The FBLC includes designing a nonlinear control law for the stabilization of the target dynamic system while the closed-loop dynamics are linear with ensured stability. The objective of the FAT is to estimate the cubic nonlinear restoring force vector using the linear parameterization of weighting and orthogonal basis function matrices. Orthogonal Chebyshev polynomials are used as strong approximators for adaptive schemes. The proposed control architecture is applied to a thin plate with a large deflection that stimulates the axial loadi

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Publication Date
Thu Nov 01 2001
Journal Name
Renewable Energy
Optoelectronic properties of a-Si1−xGex:H thin films
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Publication Date
Mon Jan 01 2007
Journal Name
Journal Of Al-nahrain University
Applications Of Strong-Lensing For Some Gravitational Lenses
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In our work present, the application of strong-Lensing observations for some gravitational lenses have been adopted to study the geometry of the universe and to explain the physics and the size of the quasars. The first procedure was to study the geometrical of the Lensing system to determine the relation between the redshift of the gravitational observations with its distances. The second procedure was to compare between the angular diameter distances "DA" calculated from the Euclidean case with that from the Freedman models, then evaluating the diameter of the system lens. The results concluded that the phenomena are restricted to the ratio of distance between lens and source with the diameter of the lens noticing.