Most studies indicated that the values of atmospheric variables have changed from their general rates due to pollution or global warming etc. Hence, the research indicates the changes of direct solar radiation values over a whole century i.e. from 1900 to 2000 depending on registered data for four cities, namely (Mosul - Baghdad - Rutba - Basra. Moreover, attemptsto correlate the direct solar radiation with the temperature values have been recorded over that period. The results showed that there is a decreasing pattern of radiation quantities over time throughout the study period, where the value of direct radiation over the city of Baghdad 5550 w/m2 was recorded in the year 1900, but this ratio decreased cle
... Show MoreIn this paper, a theoretical study to the effect of journal misalignment on the static characteristics of oil filled porous journal bearing when lubricated with couple stress fluid has been carried out.
The analytical model used through this work is for a bearing with isotropic permeability. Considering isotropic permeability the Reynolds' equation for the oil film is modified to include a so – called filter term and the effect of fluid coupled stress. The pressure equation for the porous medium is obtained from Darcy's law and continuity equation. The equation which was used to evaluate the oil film thickness was modified to include the effect of possible misalignment in longitudinal and transverse directions. The governing eq
... Show MoreObjective: The study aimed to identify the adolescents' fast foods and snacks, and find out the relationship between fast
food, snacks and adolescents' demographic data (gender and Body Mass Index). Methodology: A descriptive study
was conducted on impact of fast foods and snacks upon adolescents' Body Mass Index in secondary schools at Baghdad
city, starting from 20
th of April 2013 to the end of October 2014. Non- probability (purposive) sample of 1254
adolescents were chosen from secondary schools of both sides of Al-Karkh and Al-Russafa sectors. Data was collected
through a specially constructed questionnaire format include (12) items multiple choice questions. The validity of the
questionnaire was determined thr
Abstract
This study investigates the mechanical compression properties of tin-lead and lead-free alloy spherical balls, using more than 500 samples to identify statistical variability in the properties in each alloy. Isothermal aging was done to study and compare the aging effect on the microstructure and properties.
The results showed significant elastic and plastic anisotropy of tin phase in lead-free tin based solder and that was compared with simulation using a Crystal Plasticity Finite Element (CPEF) method that has the anisotropy of Sn installed. The results and experiments were in good agreement, indicating the range of values expected with anisotropic properties.
Keywords<
... Show MoreThis study deals with the impact of leadership styles in its three main dimensions (democratic, autocratic, lenient) as an independent variable of the dimensions of functional combustion (emotional stress, inhumanity, personal achievement). The research sought to achieve a set of goals, the most prominent of which are: studying the reality of the researched organization to identify the leadership patterns used in its management and its impact on the phenomenon of functional combustion, Moreover, knowing the extent of support for these established patterns and their contribution to mitigating the phenomenon of functional combustion in the organization's environment, and testing the impact of these leadership patte
... Show More- Epstein, B., and sobel , M. (1954)."Some Thearems Relevant to life Testing from an Exponential population" Annals of Mathematical Statistics, 25, 373 – 381 .
- Epstein, B., and Tsao, C.K.(1953) "Some Tests Based on Order Observation From Two Exponential Populations" Annals of Mathematical Statistics , 24 , 458 – 466 .
- Hogg, R.V. and Tonis, E,A. (1963), "An Iterated procedure for Testing the Equality of several Exponential Distributions" Journal of the American Statistical Association, 58 , 435 – 443.
- Kumar, S. , and patel , H. I. (1971) "ATest for the Comparision of two Exponential Disributions" Technometrics , 13 , 183 – 189 .<
Foreign trade is very important in global economies because of its impact on the sustainability of economic growth by stimulating economic activity, creating jobs and expanding production . On the other side , this policy is a major obstacle to many developing countries and the reason is due to the nature of the economies of those countries because they rely mostly on one or a few economic resources, which makes them rely mostly on exports to that resource while they import most of the needs of their local market Which makes them in a spiral of underdevelopment , dependence and economic exposure, which requires them to break that cycle and the launch of economic development Perhaps one of the most important means to a
... Show MoreThe current research deals with short term forecasting of demand on Blood material, and its' problem represented by increasing of forecast' errors in The National Center for Blood Transfusion because using inappropriate method of forecasting by Centers' management, represented with Naive Model. The importance of research represented by the great affect for forecasts accuracy on operational performance for health care organizations, and necessity of providing blood material with desired quantity and in suitable time. The literatures deal with subject of short term forecasting of demand with using the time series models in order to getting of accuracy results, because depending these models on data of last demand, that is being sta
... Show MoreThe researcher highlighted the general budget in Iraq for the period (2003-2018) facing the challenges of administrative and financial corruption, in addition to the fluctuations in oil prices, the repercussions and many problems suffered and will suffer the Iraqi government in the process of preparing the general budget of the state and weak contribution of the agricultural and industrial sectors and other economic sectors and neglect altogether, oil has become the main supplier in funding Iraq's budget after 2003, and the impact on the unemployment rates in Iraq, which recorded fluctuating rates and then increased during the period (2012-2018) to achieve this, an inductive method was adopted, using theoretical and descriptive a
... Show MoreDue to the energy crisis and the stringent environmental regulations, diesel engines are offering good hope for automotive vehicles. However, a lot of work is needed to reduce the diesel exhaust emissions and give the way for full utilization of the diesel fuel’s excellent characteristics.
A kind of cetane number improver has been proposed and tested to be used with diesel fuel as ameans of reducing exhaust emissions. The addition of (2-ethylhexyl nitrate) was designed to raise fuel cetane number to three stages, 50, 52 and 55 compared to the used conventional diesel fuel whose CN was 48.5. The addition of CN improver results in the decre
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