A random laser is a non-conventional laser whose feedback mechanism is based on dissorder-induced light. However, random lasers occur in gain media with numerous scatterers and produce coherent laser emission without any predesigned cavity. The generation of coherent emission from multiple scattering is quite general and its basic principles are shown here using sulforhodamine B-TiO suspensions system. These suspensions were pumped with 337.1 nm pulses from N2 laser and the spectral and temporal behavior of light emitted from the pumped surface was recorded. When we pump power above a certain threshold a dramatic narrowing of the emission line width and a shortening of the emitted pulses were observed. We have experimentally found that in a random laser based scattering, the threshold pumping density decreases with pump energy increased.
Among the different passive techniques heat pipe heat exchanger (HPHE) seems to be the most effective one for energy saving in heating ventilation and air conditioning system (HVAC). The applications for nanofluids with high conductivity are favorable to increase the thermal performance in HPHE. Even though the nanofluid has the higher heat conduction coefficient that dispels more heat theoretically but the higher concentration will make clustering .Clustering is a problem that must be solved before nanofluids can be considered for long-term practical uses. Results showed that the maximum value of relative power is 0.13 mW at nanofluid compared with other concentrations due to the low density of nanofluid at this concentration. For highe
... Show MoreSome of the main challenges in developing an effective network-based intrusion detection system (IDS) include analyzing large network traffic volumes and realizing the decision boundaries between normal and abnormal behaviors. Deploying feature selection together with efficient classifiers in the detection system can overcome these problems. Feature selection finds the most relevant features, thus reduces the dimensionality and complexity to analyze the network traffic. Moreover, using the most relevant features to build the predictive model, reduces the complexity of the developed model, thus reducing the building classifier model time and consequently improves the detection performance. In this study, two different sets of select
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يهدف البحث الى قياس مستوى ارتباط وتأثير القدرات المعرفية الدينامية في تنافسية الاعمال، وتكونت العينة من (155) فردا في اربعة مصانع للالبان في بغداد وهي (ابو غريب، والزراعة، والحلال، وعيون الرافدين) اذ تمثل مجتمع البحث من اصحاب المصانع، والمديرين والعاملين في السيطرة النوعية والبحث والتطوير والمهندسين والفنيين والعاملين ذوي الخبرة في صناعة الالبان. وجرى تحليل البيانات واختبار الفرضيات باستخدام الادوات الإحصا
... Show Moreيستهدف البحث الحالي التعرف إلى 1 .بناء مقياس سمات الشخصية المفضلة لدى معلمي ومعلمات التربية الخاصة في العراق من وجهة نظر ذوي اإلختصاص والعاملين في هذا المجال. 2 .مستوى توافر سمات الشخصية المفضلة لدى معلمي ومعلمات التربية الخاصة في العراق من وجهة نظر ذوي اإلختصاص والعاملين في هذا المجال. 3 .داللة الفروق اإلحصائية في سمات الشخصية المفضلة لدى معلمي ومعلمات التربية الخاصة ً في الع ارق من وجهة نظر ذوي اإلختصاص والعا
... Show MoreFinancial institutions, including banks, remain a major target for money launderers in order to transfer illegal funds to legitimate funds through limited internal audit procedures and external auditing.
The study is a study of the operations of money laundering and what can be done by the verification efforts when integrated in the fight against them, by analyzing the level of cooperative relationship and communication between them. To achieve the objectives of the study, a questionnaire prepared for this purpose was distributed to an appropriate sample of (60) auditors of the internal audit staff of the Central Bank of Iraq and the external auditors working in the Federal control foundation Accordingly , appropriate methods wer
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This paper deals with load-deflection behavior the jointed plain concrete pavement system using steel dowel bars as a mechanism to transmit load across the expansion joints. Experimentally, four models of the jointed plain concrete pavement system were made, each model consists of two slabs of plain concrete that connected together across expansion by two dowel bars and the concrete slab were supported by the subgrade soil. Two variables were dealt with, the first is diameter of dowel bar (12, 16 and 20 mm) and the second is type of the subgrade soil, two types of soil were used which classified according to the (AASHTO): Type I (A-6) and type II (A-7-6). Experimental results showed that increasing dowel bar diameter from 12 mm to 20 mm
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جمعت 50 حية مائية Natrix tessellata على وجبتين الأولى 25 حية عند فصل الربيع تحديدا من منتصف آذار الى منتصف نيسان، اما المجموعة الثانية ، 25 حية لفصل الصيف من منتصف حزيران الى منتصف تموز. اذ عزلت الذكور عن الإناث و حللت قطع من لحم الذكر و قطع من
E-commerce is the most important result of information technology in this day and age, has resulted in the use of commercial transactions to changes in economic, social, and psychological, and produced a new type of shopping, jobs, and create new job opportunities, and changed the traditional work environment. The challenge currently facing economic units is how to transfer this technology and its integration within the community, especially after the massive developments that have occurred in the areas of commercial and congested markets units, the economic and the products and services the many and varied and intensified competition among these units to achieve a profit, leading to the emergence of e-commerce as on
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