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 study of services in villages is one of the imperative matters that must be focused on, because it leads to increased attention, which reduces the differences between the countryside and the urban. The extent of its.
It is well known that community services need to be reached by a person, unlike the anchor services that reach people, here the population distribution plays an important and prominent role in signing these services, so the dispersed distribution pattern and the gathering pattern appeared in the distribution, thus an effect on the time and distance that the person walked to obtain The services are community-based. Therefore
... Show MoreDelays occur commonly in construction projects. Assessing the impact of delay is sometimes a contentious
issue. Several delay analysis methods are available but no one method can be universally used over another in
all situations. The selection of the proper analysis method depends upon a variety of factors including
information available, time of analysis, capabilities of the methodology, and time, funds and effort allocated to the analysis. This paper presents computerized schedule analysis programmed that use daily windows analysis method as it recognized one of the most credible methods, and it is one of the few techniques much more likely to be accepted by courts than any other method. A simple case study has been implement
Human resources are considered as strategic fortune for being the main driver of the development wheel in the society, and the field of education and learning is one of the main pillars of this fortune for its great effect in the process of economic and social progress of individuals. I was the subject of education to the concerns of many countries, as adopted national policies . And regional support and the reduction of constraints, so came our study (education hub for human development) to identify the role of education in human development and to identify the obstacles facing the education process and the extent of its impacts negatively on the process of human development also contribute to the knowledge of school enrollment and the
... Show MoreThe current research aims to provide a conceptual and applied frame on the subject of multi- level analysis in the research of business administration. The research tries to address some of the problems that befall the preparation of research and studies at the Arab level and local level, where the unity of theory and measurement and analysis, as well as clarify the various types of conceptual constructs and give researchers the ability to distinguish different models related to the level of analysis. On the other hand, this research provides an example of
... Show More<p>Photovoltaic (PV) systems are becoming increasingly popular; however, arc faults on the direct current (DC) side are becoming more widespread as a result of the effects of aging as well as the trend toward higher DC voltage levels, posing severe risk to human safety and system stability. The parallel arc faults present higher level of current as compared with the series arc faults, making it more difficult to spot the series arc. In this paper and for the aim of condition monitoring, the features of a DC series arc fault are analyzed by analysing the arc features, performing model’s simulation in PSCAD, and carrying out experimental studies. Various arc models are simulated and investigated; for low current arcs, the heur
... Show MoreSystem is one of the concepts that fused stages of human thought his contemplations , and the evolution of his ideas and know the universe and existence , was formed several systems and numerous multi- humanitarian field , for example : the political system , the economic system , the system of philosophical , scientific system ... etc. .The current research around trying to find the identity of the system aesthetic in general and theater in particular , the detection of compositions and how Cklath within shifts functional and conceptual , which confirms the importance of Altgria creative as characterized by the following heading towards experimentation and update ongoing , and in particular what we find in the discourse of postmodernism
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