In this study, the electro-hydraulic servo system for speed control of fixed displacement hydraulic motor using proportional valve and (PID) controller is investigated theoretically ,experimentally and simulation . The theoretical part includes the derivation of the nonlinear mathematical model equation of (valve – motor ) combination system and the derivation of the transfer function for the complete hydraulic system , the stability test of the system during the operation through the transfer function using MATLAB package
V7.1 have been done. An experimental part includes design and built hydraulic test rig and simple PID controller .The best PID gains have been calculated experimentally and simulation, speed control performance tests for the system at different thermal conditions for hydraulic oil have been done , Simulation analysis for (EHSS) using Automation Studio package V5.2 have been done . Comparison was made between experimental work and simulation work .The experimental results show good performance for (EHSS) using simple (PID) controller at hydraulic oil temperature around (60 – 70 ) and good speed response and performance for hydraulic motor with constant rotation speed (700) rpm with different load disturbance applied on the hydraulic motor .
The investigation of the effect of tempering on thermal analysis of
Al-Ti-Si alloy and its composites with MgO and SiC particles was
performed. Thermal analysis was performed before and after
tempering by DSC scan. Optical microscopy was used to identify the
phases and precipitations that may be formed in base alloy and
composites. X-ray diffraction test indicated that the Al3Ti is the main
phase in Al-Ti-Si alloy in addition to form Al5Ti7Si12 phase. Some
chemical reactions can be occurred between reinforcements and
matrix such as MgO.Al2O3 in Al-Ti/MgO, and Al4C3 and Al(OH)3 in
Al-Ti/SiC composite. X-ray florescence technique is used to
investigate the chemical composition of the fabricated specimens.
H
One of the most important challenges facing the development of laser weapons is represented by the attenuation of the laser beam as it passed through the layers of atmosphere.This paper presents a theoretical study to simulate the effect of turbulence attenuation and calculates the decrease of laser power in Iraq. The refractive index structure C_n^2 is very important parameter to measure the strength of the atmospheric turbulence, which is affected by microclimate conditions, propagation path, season and time in the day. The results of measurements and predictions are based on the Kolmogorov turbulence theory. It was demonstrated by simulations that the laser weapons in Iraq were severely affected due to the large change in temperatures,
... Show MoreThe research location is the northern part of the Basin of Limboto Lake; the focus of the research is the limestone outcrop with 24 meter thickness in Yosonegoro area. The purpose of the study is to find out facies, standard microfacies and depositional environment on Limboto limestone. The research method carried out consisted of three methods namely the measured section, petrographic analysis and biostratigraphy analysis.
The limestone facies in the Yosonegoro area consist of two facies. Then, based on sedimentary structure, composition, color, precipitation texture, terrestrial origin components and the organism content, the two facies can divided into three different microfacies. Paleobathyme
... Show MoreThe researchers aim of this research to analyze the reality of educational services in the city of Ramadi in order to reveal the efficiency of the spatial distribution of schools at the level of residential neighborhoods and the requirements of the population, based on the standards and indicators for this service.
The research problem related to the educational function of the city of Ramadi was formulated by asking about the efficiency of the spatial distribution of educational services and whether there is a balance in the distribution of schools to residential neighborhoods in a way that meets the requirements of the population, and in order to answer the research problem, the research hypothesis was formulated that there is
... Show MoreHypocrisy is found in various aspects of life, whether in religion, politics, or social parts. Hence, some of the church's hypocrisy is an outcome of different ups and downs in life. Starting with the problem in the novel, some of the hypocritical pastors engaged in an immense role in affecting the folk's lives because they persuaded people that God ordered them to do so. To accomplish their personal interests, the abusive monks disguise their verbal speech, smiles, and fine clothes like mild sheep to delusional followers, leaving them with guilt, shame, and spiritual scars. The present study aims to examine the hypocrisy and heresy of the church as portrayed in Okezie Nwoka's novel entitled God of Mercy. It reflects the source of
... Show MoreThe economy of a city has an important role not only in its establishment but also in its development. This is quite clear in the city of Baghdad throughout its history since its building in 762 A.D. In addition, most of its problems that the city is suffering from are basically related to not giving enough importance to the economic factors in the master planning of Baghdad since 1950’s. This may explain the failiars of master plans in dealing with the actual population growth and the city's inability to absorb such increases and interrelated and diverse activities which are negatively reflected on the economic variables particularly the effect on the land values, and the strong competitions amongst the land uses without previ
... Show MoreThe reciprocal relationship between the text and the mask in the printed product is one of the most important relationships that frame the level of communication between the appearance and the interior, although it is not cared for by some designers and publishing institutions. Therefore, the problem of research is determined by the following question (What is the dialectical relationship between the text and the mask in the literary books covers design?). The research aims to shed light on this problematic relationship at the level of reception and aesthetics at the same moment. The theoretical framework included two sections: the first (mask and text ... the concept and the mutual relationship), while the second section (trends in the
... Show MoreArabic calligraphy has a special status as one of the most important oriental arts, which has been enhanced by the Islamic value. The Arabic fonts have been diverse in their classification into soft lines such as Diwani, thuluth and patch lines and others, and geometrical lines such as Kufic lines and their various types. The contemporary artist was also able to adapt the Arabic calligraphy of all kinds in the construction of the painting or line formations, especially after the development of the artistic digital techniques and computer software. Here comes the role of the industrial designer as being more in touch with the practical, technical and productive life, which requires great care in adapting the line formations of the Arabic
... Show MoreOrganism is considered one of the intellectual products that search for compatibility and harmony with the natural environment. Man has adopted on since the ancient times in choosing his residence through imitating nature such as animal burrows, hives, bird nests and others of the natural manifestations being spontaneous inspirations. With the development of the age, these concepts turned into an analysis that examines the philosophy that deals with the shapes and functions of various elements in the nature as a source of inspiration, and discusses the call for contemplation and achieving benefits physically and spiritually in line with the nature of the organic thought that seeks to keep up with modern technologies that are characterize
... Show MorePrevious experimental studies have suggested that hot mixed asphalt (HMA) concrete using hydrated lime (HL) to partially replace the conventional limestone dust filler at 2.5% by the total weight of all aggregates showed an optimum improvement on several key mechanical properties, fatigue life span and moisture susceptibility. However, so far, the knowledge of the thermal response of the modified asphalt concrete and thermal influence on the durability of the pavement constructed are still relatively limited but important to inform pavement design. This paper, at first, reports an experimental study of the tensile fatigue life of HMA concrete mixes designed for wearing layer application. Tests were conducted under three different temperatur
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