Thermal Effects for Shaft-Pre-Stress on Rotor Dynamic System

This Paper outlines study behaviour of rotating shaft with high speed under thermal effects. The method of obtaining the frequency response functions of a rotor system with study whirl effect in this revision the raw data obtained from the experimental results (using Smart Office program) are curve-fitted by theoretical data regenerated from some of the experimental data and simulating it using finite element (ANSYS 12). (FE) models using the Eigen analysis capability were used to simulate the vibration. The results were compared with experimental data show analysis data with acceptable accuracy and performance. The rotating effect causes un-symmetry in the system matrices, resulting in complexity in decoupling the mathematical models of the system for the purpose of modal analysis. Different method is therefore required, which can handle general system matrices rather than symmetrical matrices, which is normal for passive structures. Mathematical model of the system from the test data can be assembled. The frequency response functions are extracted, Campbell diagram are draw and simulated. (FE) is used to carry out such as simulation since it has good capability for Eigen analysis and also good graphical facility. Keywords: Thermal effects, Modelling, Campbell diagram, Whirl, Rotor dynamics.Comment: Published by: Academic Research Publishing Agency. All rights reserved, 6 pages, 4 figures, 1 pictur

Estimation Of The Economic Impact Of Brain Drain On The Labor Expelling Country

The emigration of human resources leads to many losses for the labor expelling country. Such losses would, without doubt, adversely affect the economic and social development programs in multiple aspects including state loss of migrants efforts in producing the desired growth whether in the planning and preparation stages or in the implementation stage and the cost opportunity represented in the financial resources spent on the migrants prior to their emigration which could have been utilized in other areas taking into account, the limited financial resources in the underdeveloped countries which are mainly labor expelling countries. Hence, the loss of such countries is doubled. They neither benefited from their labor after years of spending in education and health, nor they saved their funds and exploited in other alternatives like improving education and health services, providing job opportunities for residents, improving the innovation climate or even increasing civil production to improve the living standards of individuals. The study is devoted to analyze and measure of economic effects of labor emigration in the labor expelling economy, through taking Egypt – the largest Arab country suffering from this phenomenon- as an example and using data derived from Egyptian sources. Estimates have emphasized growing losses generated by the Egyptian labor emigration, especially by brain drain. The paper concludes that measures and policies must be adopted to stop this drain by addressing the causes of labor emigration or rather, the existing properties of the labor expelling country. Also, efforts must be made to ensure that data related to immigration is always available, updated and estimated by official bodies having human, financial and technical capabilities for this task

Assessing The Impact Of The Global Financial Crisis On GCC Countries

No doubt, the international financial crisis that started in the United States of America will cast its effects on all countries of the world, developed and developing. Yet these effects vary from one country to another for several reasons. The GCC countries would not escape these negative effects of this severe crisis. The negative effects of the crisis on gulf countries come from many aspects: first, decrease in price of oil on whose revenues the development programs in these countries depend; second, decrease in the value of US$and the subsequent decrease in the assets owned by these countries in US$; third, a case of economic stagnation will prevail in the world with effects starting to appear. It is obvious that this would be reflected on the real sector in the economies causing a series of negative effects through decrease of the world demand for exports of GCC countries of oil, petrochemicals and aluminum.  Lastly, increased inflation rates with decreased interest rates will result in a decrease in real interest with an accompanying decrease in incentives for saving and consequently investment and economic development. The main aim of the research is to assess the economic effects of the global financial crisis on GCC countries. The paper results are that the big reserves of foreign currencies achieved by the GCC countries in the past few years have helped increase their ability to bear the effects of the financial effects on one hand and their ability to adopt expansionary policies through pumping liquidity to absorb the regressive effects of the crisis on the other. The paper recommends the necessity of taking precautionary procedures for the effects which will result from the expansionary policies effective in GCC countries

Small-Scale Catchment Analysis of Water Stress in Wet Regions of the U.S.: An Example from Louisiana

Groundwater is increasingly being overdrafted in the Southeastern U.S., despite abundant rainfall and the apparent availability of surface water. Using the state of Louisiana as an example, the current study quantifies the stresses on water resources and investigates the potential for opportunities to use surface water in lieu of groundwater pumping. The assessment is based on a fine watershed scale (12-digit Hydrological Unit Code [HUC] boundaries) water balance between the availability of surface and groundwater and surface water and groundwater demand. Water demand includes environmental flows, as well as public supply, rural domestic, industrial, power generation, agricultural, and aquaculture sectors. The seasonality of water stress is also addressed by incorporating monthly variations in surface water supply and irrigation demands. We develop several new weighting schemes to disaggregate the water withdrawals, provided by the U.S. Geological Survey on a county scale, to the HUC12 scale. The analysis on the smaller HUC12 scale is important for identifying areas with high water stress that would otherwise be masked at a larger scale (e.g. the county or HUC8 watershed scales). The results indicate that the annual water stress in Louisiana is below one (i.e. there is more water available than is used) for most watersheds; however, some watersheds (15 of the HUC12 units) show stresses greater than one, indicating an insufficient water supply to meet existing demands. The areas of the highest water stress are largely attributable to water consumption for power generating plants or irrigation. Moreover, estimating the stresses on surface water and groundwater sources separately confirms our speculation of abundant surface water and demonstrates a significant over-drafting/deficit of groundwater in many of the states aquifer systems. These results have implications for identifying new opportunities for reallocation of surface water use to reduce groundwater pumping and improve water sustainability in the region. Seasonal fluctuations in surface water supply and water withdrawals for irrigation highlight the fact that the water system is under more stress during the summer season. This observation underscores the need for infrastructure for shortterm surface water storage in agricultural regions. The water budget analysis presented here can be useful for stakeholders in developing water management plans and can also help to inform the development of a water code that will enable Louisiana to successfully manage and conserve its water resources for the future

Defect Diagnosis in Rotors Systems by Vibrations Data Collectors Using Trending Software

Vibration measurements have been used to reliably diagnose performance problems in machinery and related mechanical products. A vibration data collector can be used effectively to measure and analyze the machinery vibration content in gearboxes, engines, turbines, fans, compressors, pumps and bearings. Ideally, a machine will have little or no vibration, indicating that the rotating components are appropriately balanced, aligned, and well maintained. Quick analysis and assessment of the vibration content can lead to fault diagnosis and prognosis of a machine's ability to continue running. The aim of this research used vibration measurements to pinpoint mechanical defects such as (unbalance, misalignment, resonance, and part loosening), consequently diagnosis all necessary process for engineers and technicians who desire to understand the vibration that exists in structures and machines. Keywords- vibration data collectors; analysis software; rotating components.Comment: 11 pages,6 figures,1 pictuer,1 schem

Clinical comparison of three aligner systems

Objectives: The object of this clinical study was to compare three different aligner systems. The aim was to help the ortho-dontist with choosing an adequate aligner philosophy/therapy system.Materials and methods: This study included 60 randomly chosen patients. Mild to moderate cases were selected, and patients were assigned to three groups of 20 patients each. One group was treated with Invisalign (20 patients), the sec-ond group was treated with CA Clear Aligner and the third group of patients was treated with the Orthocaps aligner sys-tem. In all cases, attachments were used to additionally en-hance the fitting and efficiency of the aligner.Results: All investigated aligner systems achieved the predict-ed goal of the treatment, although with significant differences concerning accuracy, the predicted duration of treatment and the number of refinements. Significant differences were deter-mined, especially regarding the efficiency, duration and cost of treatments.Conclusion: Aligner orthodontics allow for handling difficult treatment cases despite different aligner philosophies, differ-ent materials and different durations of treatment. There were significant differences concerning the envisaged time of treatment. In moderate cases, a significant difference con-cerning duration and costs was determined. IntroductionThere are many orthodontic systems on the market, and it can be difficult for clinicians to choose. The aim of this clinical study was to compare three different aligner systems. The main differences between the systems are described. The study combines a report of 60 treated patients, treated with three currently available systems. Comparisons were made based on factors useful to the clinician, including comfort, cost, and whether the intended treatment goal was reache

Madrasah Education System and Terrorism: Reality and Misconception

Since the terrorist attacks on September 11, 2001, the Islamic schools known as madrasah havebeen of increasing interest to analysts and to officials involved in formulating U.S. foreign policytoward the Middle East, Central, and Southeast Asia. Madrasah drew added attention when itbecame known that several Taliban leaders and Al-Qaeda members had developed radicalpolitical views at madrasah in Pakistan, some of which allegedly were built and partially financedthrough Saudi Arabian sources. These revelations have led to accusations that madrasah promoteIslamic extremism and militancy, and are a recruiting ground for terrorism. Others maintain thatmost of these religious schools have been blamed unfairly for fostering anti-U.S. sentiments andargue that madrasah play an important role in countries where millions of Muslims live in povertyand the educational infrastructure is in decay. This paper aims to study a misconception of therole and functions of Islamic traditional religious schools which have been linked with theactivities of terrorism. The study will be specifically focus on practice of the traditional Islamicschool, which is locally called as ‘madrasah system\u27

The Prediction of Tear Strength of plain weave fabric Using Linear Regression Models

The aim of the study is to predict the tear strength of plain weave fabric by knowing the yarn count, yarn tensile strength and the fabric linear density. A total of nine fabric samples (produced of three different yarn counts which were 36.88, 29.50 and 9.83 tex) were produced in deferent densities at weft direction which were 4.33, 7.08 and 8.26 threads per cm, while the density was fixed at the warp direction in 9.84 ends per cm . Tensile strength was tested for these fabrics at warp and weft direction. The results were analyzed and incorporated in the Min-Tab program and the development of regression coefficients and correlation between variables to obtain equations to predict the tear strength at warp and weft direction