Free Space Optics (FSO) plays a vital role in modern wireless communications due to its advantages over fiber optics and RF techniques where a transmission of huge bandwidth and access to remote places become possible. The specific aim of this research is to analyze the Bit-Error Rate (BER) for FSO communication system when the signal is sent the over medium of turbulence channel, where the fading channel is described by the Gamma-Gamma model. The signal quality is improved by using Optical Space-Time Block- Code (OSTBC) and then the BER will be reduced. Optical 2×2 Alamouti scheme required 14 dB bit energy to noise ratio (Eb/N0) at 10-5 bit error rate (BER) which gives 3.5 dB gain as compared to no diversity scheme. The results show that using Multiple-Input-Multiple-Output (MIMO) technique represented by Alamouti scheme gives the improved BER performance as compared with no diversity (Single-Input-Single-Output (SISO)) technique.
Background: For various reasons, inguinal hernia repair under local anaesthesia is not well accepted to both patients and surgeons. The patients fear from pain and surgeons need full relaxation and co-operation to do successful hernia repairMethods: purpose of this study is to evaluate the effectiveness of local anaesthesia in inguinal hernia repair.prospective study was made from January 2011-0ctober 2013 , on a total of 50 patients with inguinal hernia operated on under local anaesthesia. Patients were selected primarily on the basis of their willingness to accept the procedure after the technique was described to them.Results: In this study 50 patient and 58 herniorrhaphies done for them during a period of about 34months were evaluate
... Show Moreتنتاب العلاقةَ الأمريكية الإيرانية تجاذباتٌ ومشاحنات أدخلت العالم في حالة من الغموض السياسي، وجعلت بعض المراقبين والمحللين السياسيين لا يستبعدون توجيه الولايات المتحدة الأمريكية أو إسرائيل ضربة عسكرية لإيران، إذ يرى المدقق في واقع تلك العلاقة المضطربة: أن الأمور كلما بلغت حافة الهاوية عادت من جديد إلى ساحة الحوار والمفاوضات، ويبدو: أن الإستراتيجية الأمريكية التي يتبعها الرئيس (باراك أو
... Show Morethis research five grammatical terminology, and predicate and ascribed to it and added and genitive, examined scientific accuracy envisaged in placed and how they conform to the content then proposed five alternative terminology, and proved that this alternative terminology reflects more accurately the content of conventional terminology in Arabic grammar lesson, logical approach relies on analysis of morphological derivation of the term and its language, and recommended research to pursue critical studies in grammatical terminology, because such research has Significant impact in removing the grammatical ambiguity of some scholars, as well as instrumental in the development of methods of teaching Arabic grammar, to return to the relatio
... Show MoreVirtual reality technology is the science of the embodiment of things and move spontaneously among non-real from one place to another with the full sense of the form, touch, sound, enables the user tried out and deal with it, like a real natural world and open up new worlds for human ambitious to let him overlooks the supposed world. Internet has become part of our daily lives, especially with the presence of mobile devices; that revolutionized the world of social networking. Access to information and build relationships change in the era of digital technology. The woman is not in isolation from this era; she found to herself a wide area for the production of ideas.
When we talk about woman in the modern means of communication, this a
well log analysis is used to determine the rock properties like porosity, water saturation, and shale volume. Archie parameters in Archie equation, which sometimes considered constants greatly affect the determination of water saturation, also these parameters may be used to indicate whether the rocks are fractured or not so they should be determined. This research involves well logging analysis for Zubair formation in Luhais field which involves the determination of Archie parameters instead of using them as constant.
The log interpretation proved that the formation is hydrocarbon reservoir, as it could be concluded from Rwa (high values) and water saturation values (low values), the lithology of Zubair from cro
... Show MoreThe objective of this work is to study the influence of end milling cutting process parameters, tool material and geometry on multi-response outputs for 4032 Al-alloy. This can be done by proposing an approach that combines Taguchi method with grey relational analysis. Three cutting parameters have been selected (spindle speed, feed rate and cut depth) with three levels for each parameter. Three tools with different materials and geometry have been also used to design the experimental tests and runs based on matrix L9. The end milling process with several output characteristics is solved using a grey relational analysis. The results of analysis of variance (ANOVA) showed that the major influencing parameters on multi-objective response w
... Show MoreTo deduct the childhood status in Iraq, it was important manner to use statistical tools and approaches concerned with interpreting the causal relationships and their attitudes and use classification method for the important effects (variables) to draw an obvious picture of the phenomena under study in order to make it useful through investing, updating and improving it in by demographic studies in the future. Two statistical methods had been used in the field of analyzing data of multivariate analysis namely, Cluster Analysis and Factor Analysis.
The present study focuses on four fundamental axes .The nutrition axis, health axis, Educational axis, and the social axis. The study has ca
... Show MoreRegression analysis models are adopted by using SPSS program to predict the 28-day compressive strength as dependent variable and the accelerated compressive strength as independent variable. Three accelerated curing method was adopted, warm water (35ºC) and autogenous according to ASTM C C684-99 and the British method (55ºC) according to BS1881: Part 112:1983. The experimental concrete mix design was according to ACI 211.1. Twenty eight concrete mixes with slump rang (25-50) mm and (75-100)mm for rounded and crushed coarse aggregate with cement content (585, 512, 455, 410, 372 and 341)Kg/m3.
The experimental results showed that the acc
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