Zigbee, which has the standard IEEE 802.15.4. It is advisable method to build wireless personal area network (WPAN) which demands a low power consumption that can be produced by Zigbee technique. Our paper gives measuring efficiency of Zigbee involving the Physical Layer (PL) and Media Access Control (MAC) sub-layer , which allow a simple interaction between the sensors. We model and simulate two different scenarios, in the first one, we tested the topological characteristics and performance of the IEEE802.15.4 standard in terms of throughput, node to node delay and figure of routers for three network layouts (Star, Mesh and Cluster Tree) using OPNET simulator. The second scenario investigates the self-healing feature on a mesh topology from earlier design until it supports a large number of end points (>64,000) with dynamic routing. The self-healing is done by removing a router from the network during operation, and seeing the end devices find an alternate path to communicate with the coordinator.
This research aims to know the reality of succession planning in the researched organization and how it occupies the important jobs in the organization and its readiness for sudden and urgent events that lead to the vacancy of these jobs, and the importance of this research is that it is one of the rare Arab and Iraqi studies and research in this field, as it is one of the first researches It deals with the reality of succession planning in light of the retirement law No. (26) of 2019, and the research problem was the absence of consecutive planning programs and the weak preparation of suitable candidates to face sudden and urgent conditions as replacements for current leaders who occupy the leading and key positions in the depar
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In this study, the behavior of screw piles models with continuous helix was studied by conducting laboratory experimental tests on a single screw pile that has several aspect ratios (L/D) under the influence of static axial compression loads. The screw piles were inserted in a soft soil that has a unit weight of 18.72 kN/m3 and moisture content of 30.19%. Also, the soil has a liquid limit of 55% and a plasticity index of 32%. A physical laboratory model was designed to investigate the ultimate compression capacity of the screw pile and measure the generated porewater pressure during the loading process. The bedding soil was prepared according to the field unit weight and moisture content and the failure load was assumed correspondin
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The present work represents a theoretical study for the correction of spherical aberration of an immersion lens of axial symmetry operating under the effect of space charge, represented by a second order function and preassigned magnification conditions in a focusing of high current ion beams. The space charge depends strongly on the value of the ionic beam current which is found to be very effective and represents an important factor effecting the value of spherical aberration .The distribution of the space charge was measured from knowing it's density .It is effect on the trajectory of the ion beam was studied. To obtain the trajectories of the charged particles which satisfy the preassined potential the axial electrostatic potential w
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The aim of the research is to determine the impact of evaluation of investment projects after the preparation of investment budgets taking into consideration within the investment budgets the concept of competitive strategy, as the harmony between the preparation of investment budgets and competitive strategy will contribute to the success of economic unity and achieve profits well and achieve a competitive advantage. Strategies for economic units because the most important factor to them is the costs produced and the progress of the research problem is focused on "Is it possible to include a strategy of competition, especially within the investment budget when prepared The study concluded that the investment plan prepared by the
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Water samples were collected from output of water for Al-Wahda plant where located in al-karrada area in Baghdad city to study water contamination with bacteria, fungi and Algae. The study lasted one year started on August, 2016 to July,2017.Results were acquired according to two tests performed, the first is biological test included total coliform,E.coli, pseudomonas aeruginosa, total fungi, Diatom and non Diatom Algae and the second is physiochemical test included temperature, turbidity and residual chlorine. The results of bacteria were within the permitted specification in the Iraqi standards no. 14/2270 for the year 2015 except August was exceeded the permitted standard for total coliform, it was 1.1< cell/100 ml.Total Fungi, Dia
... Show MoreIn this paper, variable gain nonlinear PD and PI fuzzy logic controllers are designed and the effect of the variable gain characteristic of these controllers is analyzed to show its contribution in enhancing the performance of the closed loop system over a conventional linear PID controller. Simulation results and time domain performance characteristics show how these fuzzy controllers outperform the conventional PID controller when used to control a nonlinear plant and a plant that has time delay.
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