In the present work, the surface properties of mixed binary surfactants containing sodium dodecylbenzene sulfate (SDBS) and Tween 80 (TW80) surfactants in aqueous solutions were studied at temperature 293 K using surface tension measurements. The critical micelle concentration (cmc) magnitude for both individual surfactants and their mixtures were established the obtained results revealed that the magnitude of cmc of the mixtures are less than the magnitude of individual surfactants and decrease with the increase in Tween 80 percent in solution which indicate the nonideal mixing of the two surfactants. The values of molecular interaction parameters and the mole fraction of surfactants in the micelle (X1) were calculated on the basis of Rubingh’s model and showed that the interaction parameter is always negative but at 0.9 mole fraction of TW80 surfactant (α1) is positive
An automatic text summarization system mimics how humans summarize by picking the most significant sentences in a source text. However, the complexities of the Arabic language have become challenging to obtain information quickly and effectively. The main disadvantage of the traditional approaches is that they are strictly constrained (especially for the Arabic language) by the accuracy of sentence feature functions, weighting schemes, and similarity calculations. On the other hand, the meta-heuristic search approaches have a feature tha
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يعد الغضب من المظاهر الانفعالية الشائعة في مرحلة الطفولة المبكرة وذلك بسبب كثرة المواقف المثيرة لغضب الطفل في هذه المرحلة ، كما ان الطفل في هذه المرحلة سرعان ما يكتفي في كثير من الاحيان بان غضبه وبكائه طريقة سهلة للوصول الى ما يريد . ويعد المختصون في هذا المجال ، بان نوبات غضب الاطفال ، هي شيء عام طبيعي عند جميع الاطفال ، لكن عندما تكون نوبات عنيفة
... Show MoreThis paper presents a robust control method for the trajectory control of the robotic manipulator. The standard Computed Torque Control (CTC) is an important method in the robotic control systems but its not robust to system uncertainty and external disturbance. The proposed method overcome the system uncertainty and external disturbance problems. In this paper, a robustification term has been added to the standard CTC. The stability of the proposed control method is approved by the Lyapunov stability theorem. The performance of the presented controller is tested by MATLAB-Simulink environment and is compared with different control methods to illustrate its robustness and performance.
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لقد حدا بالمهتمين في الميدان التربوي، والادارة التربوية بصورة خاصة، ان يجدوا علاقات ايجابية بين متغيرات الميدان التربوي عامة والاداري بصورة خاصة وقد تمخض هذا عن وجود علاقة ايجابية بين اداء المديرين ورؤساء الاقسام ودرجة التقويم، ومن هنا يتضح انه كلما كان التقويم عالياً في درجته، يتضح ان هناك اداءً فاعلاً ولكن ليس بالشكل الحقيقي لمعنى التقويم ما لم يكن هناك
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بين الحين والآخر تتصاعد الصيحات مطالبة بإصلاح النظام التعليمي لكي يتوافق هذا النظام مع ما يحدث في العالم من تطورات علمية وتكنولوجية تترك بصماتها على مختلف قطاعات الحياة .
ويعد المعلم وبلا شك ركنا أساسيا في هذا النظام ،وذلك لما للمعلم من تأثير أساسي في عملية التعليم والتعلم . ماذا يجدي إذا ما طورنا مناهجنا، واحسنا مباني مدارسنا، وأكثرنا من الوسائل والتقنيات ،ولم نوفر المع
... Show MoreThe study of the Baghdad personalities is an important issue because the owners of these personalities usually belong to the elite, which play a distinct role in the development of any society in all political, economic, social and cultural fields. These include the study of the personal personality of Father Anastas Marie Carmeli to highlight many aspects of personality And his clear fingerprints on the movement of society in the field of culture and thought
That Karamli's efforts in the field of language, literature and history made him one of the most prominent pioneers of Renaissance late in the history of modern Iraq
In linear regression, an outlier is an observation with large residual. In other words, it is an observation whose dependent-variable value is unusual given its values on the predictor variables. An outlier observation may indicate a data entry error or other problem.
An observation with an extreme value on a predictor variable is a point with high leverage. Leverage is a measure of how far an independent variable deviates from its mean. These leverage points can have an effect on the estimate of regression coefficients.
Robust estimation for regression parameters deals with cases that have very high leverage, and cases that are outliers. Robust estimation is essentially a
... Show MoreIn this work, the synergistic effect of chlorinated rubber (additive I),with zeolite 3A (additive II), zeolite 4A (additive III), and zeolite 5A (additive IV) in (1:1) weight percentage, on the flammability for unsaturated polyester resin was studied in the weight ratios for (3,7,10,13&15%) by preparing films of (130×130×3) mm in diameters. Three standard test methods used to measure were the flame retardation which are; ASTM: D-2863, ASTM: D- 635& ASTM: D-3014. Results obtained from these tests indicated that all of the additives were effective additive IV has the highest efficiency as a flame retardant.
The banking sector is currently facing great challenges resulting from intense competition in the financial environment, and this is what makes the supreme audit bodies and the Central Bank audit as the highest supervisory authority on banks in order to achieve profit and not be exposed to loss, and this requires identifying the banking strengths and risks that constitute points Weakness that affects the future performance and the life of the bank, which requires special supervisory care, and from this point of view, the research aims to use the CAMELS model as a control tool in banks, through the use of its six indicators: capital adequacy, asset quality, management quality, profits, liquidity And sensitivity to market risks, th
... Show MoreIn this article, the lattice Boltzmann method with two relaxation time (TRT) for the D2Q9 model is used to investigate numerical results for 2D flow. The problem is performed to show the dissipation of the kinetic energy rate and its relationship with the enstrophy growth for 2D dipole wall collision. The investigation is carried out for normal collision and oblique incidents at an angle of . We prove the accuracy of moment -based boundary conditions with slip and Navier-Maxwell slip conditions to simulate this flow. These conditions are under the effect of Burnett-order stress conditions that are consistent with the discrete Boltzmann equation. Stable results are found by using this kind of boundary condition where d
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