In this paper the effect of engagement length, number of teeth, amount of applied load, wave propagation time, number of cycles, and initial crack length on the principal stress distribution, velocity of crack propagation, and cyclic crack growth rate in a spline coupling subjected to cyclic torsional impact have been investigated analytically and experimentally. It was found that the stresses induced due to cyclic impact loading are higher than the stresses induced due to impact loading with high percentage depends on the number of cycles and total loading time. Also increasing the engagement length and the number of teeth reduces the principal stresses (40%) and
(25%) respectively for increasing the engagement length from (0.15 to 0.23) and the number of teeth from (8 to 10). while increasing the other parameters (amount of applied load, wave propagation time, number of cycles, and initial crack length) increase the principal stresses at the root of the tooth (37% when the applied load rises from (8 KN to 11KN) and (62% when the wave
propagation time rises from (0.5 to 1).
In this paper, a single link flexible joint robot is used to evaluate a tracking trajectory control and vibration reduction by a super-twisting integral sliding mode (ST-ISMC). Normally, the system with joint flexibility has inevitably some uncertainties and external disturbances. In conventional sliding mode control, the robustness property is not guaranteed during the reaching phase. This disadvantage is addressed by applying ISMC that eliminates a reaching phase to ensure the robustness from the beginning of a process. To design this controller, the linear quadratic regulator (LQR) controller is first designed as the nominal control to decide a desired performance for both tracking and vibration responses. Subsequently, discontinuous con
... Show MoreThe present research was conducted to investigate the effectiveness of a training program to improve some aspects of sensory integration disorder and its effect on self-direction among a sample of children with intellectual disabilities. The study sample consists of (10 subjects as an experimental group) were exposed to the training program، and the control group consists of (10 subjects as a control group) were not exposed to the training program. The study included the following tools: A scale of self-direction for intellectual disability (prepared by the researcher). Training program (prepared by the researcher). The Results of the study showed the following: There are no statistically significant differences between the means ranks
... Show MoreThe research aims to get acquainted with the evaluation of the reality of the application of the curriculum axis from among the eight Iraqi academic accreditation standards in a sample of governmental and private universities and colleges in Iraq and to identify the main and secondary reasons for it as well as to provide proposed mechanisms and procedures to help reduce gaps, If the research problem is represented in the weak availability of the requirements of the curriculum axis in universities and colleges (the study sample) due to the weak documentation and successful implementation of them and interest in them is still below the level of ambition, In order to arrive at scientific facts, the researchers adopted the comparativ
... Show MoreThe Iraqi economy has suffered for a long period of inflation because of the Iraq war and the resolutions and the sanctions that were imposed on Iraq, this phenomenon overshadowed at various aspects of the economy including the tax revenue that the State seeks to optimize the total income for the budget, the research covers the years 1990-2010, these years have been divided according to the country's economic variables.
The research adopted on econometrics analysis that is based on the information and data available on topics and has been using statistical methods to test functions are formulated.
Research concluded that rates of inflation and GDP impact is limited to direct taxation and indirect in current prices a
... Show MoreThe study of Shiranish Formation rocks in southern part of Iraq at Ansab area well (KH-6)
were carried out. The formation is tongued with tayarat formation, which bounded from top
and bottom, the upper tongue at thickness 49m. and tongued at depth (476-525m.) the lower
tongue at thickness 4m. tongued at (541-537m.).
The rocks of this formation were divided into three sedimentary microfacies:
1- Dolomitized formininferal Wackestone facies.
2- Dolomitized formininferal Mudstone facies.
3- Dolostone facies.
34 slides were investigated depending on mineralogical, compositional and biological
processes and compared diagenesis which reflect open marine shelf at lower part of formation
(F.Z.2) (S.M.F.8), but at the
In light of the increasing interest in Child-rearing in nurseries and kindergartens and the most important experiences gained by the child at this stage that form the basis for the subsequent stages of her/his physical mental and social growth.
The significance of the research concentrates the need to asses the affecting variables on the child growth to create opportunities for her/him to have intact rearing.
The research also aims to classify these variables at each age level and highlight its moral role.
The problem of the research is the lack of clarity of different variables impact of the child growth in different age levels in nurseries and kindergart
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