هندسة المباني

تقنيات حديثة في الخرسانة عالية الكفاءة

لقد حاول المعماريون والمهندسون المتخصصون بتكنولوجيا مواد البناء، من تطوير خواص القوة ، والتحمل لمادة الخرسانة ، حتى بات إستخدام الخرسانة التقليدية بخواصها المعروفه إساءة للمبنى والبيئة ، وكما يقولون فإن الحاجة أم الإختراع، فكانت الحاجة إما لمباني تناطح السحاب،وأبراج تصل إلى ارتفاعات غير تقليدية ، ومن أهم اسباب الإختراع والتطوير مادة الخرسانة عالية الكفاءة  .High performance concrete (HPC) لكن ماهي …

أكمل القراءة »

الطوب الهوائي المجهز -طوب الحاضر والمستقبل

 الملف المرفق عن كيفية التصنيع ومكونات الطوب الهوائي المجهز  Autoclaved Aerated Concrete Block- AAC   والذي يطلق علية المتخصصون طوب الحاضر والمستقبل، يحوي الملف المرفق بالإضافة إلى ذلك اهم خصائصها الفيزيائية والميكانيكيهالمقاله المرفقة من إعداد:  م . رائد العطل،  مهندس معماري،  ماجستير تكنولوجيا مواد البناء  

أكمل القراءة »

PERISTALTIC TRANSPORT OF A COMPRESSIBLE VISCOUS LIQUID IN AN AXISYMMETRIC CYLINDRICAL PORE WITH SLIP AT THE WALLS

للكاتبين : Islam M. EL-Desoky and A. A. Mousa Department of Basic Engineering sciences, Faculty of Engineering, Menofia University, Shebin El-Kom, Menofia, Egypt. ABSTRACT In real systems, there is always a certain amount of slip, which, however, is hard to detect experimentally because of the required space resolution. In this paper, the motion of a compressible viscous liquid with “slip” …

أكمل القراءة »

AN EFFICIENT INTERACTING BOUNDARY LAYER SOLVER

للكاتب : Tarek M. A. El-Mistikawy Department of Engineering Mathematics and Physics, Faculty of Engineering, Cairo University, Giza, Egypt. ABSTRACT An efficient numerical solver for the two-dimensional supersonic interacting boundary layer equations is constructed. It is a two-sweep iterative approach that converges fast with the use of an enhancing parameter. It uses variable step sizes in both the streamwise and …

أكمل القراءة »

THREE DIMENSIONAL LAMINAR FLOW OF HERSCHEL-BULKLEY FLUIDS IN THE ENTRANCE REGION OF A RECTANGULAR DUCT

للكاتب : M. E. Sayed-Ahmed and Karem M. Kishk Department of Engineering Mathematics and Physics, Faculty of Engineering, Fayoum University   ABSTRACT In this study, we present a numerical solution for three dimensional laminar flow of Herschel-Bulkley non-Newtonian fluids in the entrance region of a rectangular duct. The governing equations are solved iteratively by using finite difference method to obtain …

أكمل القراءة »

A DISCONTINUOUS FUNCTIONAL CAUCHY PROBLEM

للكاتب : E. R HASSAN Faculty of Engineering, Al-A zhar University, Nasr City, Cairo, Egypt. ABSTRAT. The existence of extremal solutions of the following functional Cauchy prob-lem [FCP] is investigated here. The main results established for non-funational Cauchy problem [N-FCP] in R [J. Math. Anal. Appl.198(1996),657-670] are generalized here in R, as well as in R’as well as in Rⁿ

أكمل القراءة »

THERMODYNAMIC MODELLING OF THE EXCESS GIBBS ENERGY AND ASSESSMENT OF THE TERNARY SYSTEM (GA-P-IN)

للكاتبين : Y. DJABALLAH and A. BELGACEM-BOUZIDA Laboratoire d’Etude Physico-Chimique des Matériaux (LEPCM) Physics Department, Faculty of Science, University of Batna, Algeria ABSTRACT Three semiconductor binary systems (Ga-P), (P-In) and (Ga-In) were optimized, using CALPHAD method and the polynomial Redlich-Kister model to describe the Gibbs energy of the liquid phase. Together with published data on (GaP-PIn) pseudobinary system, isothermal sections …

أكمل القراءة »

APPLICATION OF THE MARQUARDT-LEVENBERG MINIMIZATION METHOD TO OPTIMIZE PARAMETERS OF A THERMODYNAMIC MODEL

للكاتبين : N. BOUKHALFA1 and A-H. MÉNIAI2 1Department of Industrial Chemistry. University of Biskra, Algeria. 2Department of Industrial Chemistry. University of Constantine, Algeria ABSTRACT In this modeling work, we have applied the Marquardt-Levenberg method to optimize parameters of a thermodynamic model. The mathematical method was applied for 11 systems including aqueous solutions of electrolytes. The thermodynamic model used requires three …

أكمل القراءة »

AN EXTENSION OF THE MAJORANA UNIQUENESS THEOREM TOBANACH AND HILBERT SPACES

للكاتب : E. R. HASSAN Department of Mathematics and Physics, Faculty of Engineering, Al-Azhar University, Nasr City,Cairo, Egypt. ABSTRACT In [Proc. Ame. Math. Soc. vol.111, n01,1991] Majorana has considered the question of uniqueness for Cauchy problem for ordinary differential equation in R. The present paper extends these results to certain class of one-dimensional nonlinear integral equation of Volterra type, as …

أكمل القراءة »

A PROPOSED SOLUTION FOR THE LONGITUDINAL IMPACT OF A RIGID BODY ON AN ELASTIC ROD

للكاتب : Hafez G.H.M. Faculty of Engineering, Ain Shams Univ., Cairo, Egypt. ABSTRACT The longitudinal impact of a rigid body on a flexible rod is theoretically investigated. The mathematical model is numerically solved by the method of characteristics. The boundary conditions at the contact end are fully discussed. A new treatment for the contact end is then developed without using …

أكمل القراءة »