Stick- slip is the continuous stopping& release of the Bit/BHA due to the irregular down-hole rotation prompted by the existing relationship between the friction torque and the torque applied from the surface to free the bit.

   Friction coefficient between BHA and wellbore is the main player of stick slip amount, which can be mitigated by support a good lubricators as additives in drilling mud.

   Mathematical (or empirical) solves should be done through adjusting all parameters which supposed to reduce stick- slip as low as possible using different models, one of the main parameters is drilling mud. As per Nanoparticles drilling fluid is a new technology that offers high performance

Traditionally, path selection within routing is formulated as a shortest path optimization problem. The objective function for optimization could be any one variety of parameters such as number of hops, delay, cost...etc. The problem of least cost delay constraint routing is studied in this paper since delay constraint is very common requirement of many multimedia applications and cost minimization captures the need to
distribute the network. So an iterative algorithm is proposed in this paper to solve this problem. It is appeared from the results of applying this algorithm that it gave the optimal path (optimal solution) from among multiple feasible paths (feasible solutions).

The method binery logistic regression and linear discrimint function of the most important statistical methods used in the classification and prediction when the data of the kind of binery (0,1) you can not use the normal regression therefore resort to binary logistic regression and linear discriminant function in the case of two group in the case of a Multicollinearity problem between the data (the data containing high correlation) It became not possible to use binary logistic regression and linear discriminant function, to solve this problem, we resort to Partial least square regression.

In this, search the comparison between binary lo

In this paper, a least squares group finite element method for solving coupled Burgers' problem in   2-D is presented. A fully discrete formulation of least squares finite element method is analyzed, the backward-Euler scheme for the time variable is considered, the discretization with respect to space variable is applied as biquadratic quadrangular elements with nine nodes for each element. The continuity, ellipticity, stability condition and error estimate of least squares group finite element method are proved.  The theoretical results  show that the error estimate of this method is . The numerical results are compared with the exact solution and other available literature when the convection-dominated case to illustrate the effic

العوامل المؤثرة في نشأة النظام السياسي الامريكي

السياسة الامريكية وحركة الاصلاح السياسي في السودان

وظائف الدولة (في الفكر السياسي العربي الاسلامي)

تعد ظاهرة النخبة من اهم الموضوعات التي يعنى بها دارسو العلوم السياسية، اذ تشكل هذه الظاهرة محور نشاطات الجماعة السياسية، وبالرغم من تباين النظريات المتعلقة بتفسير وجود هذه الظاهرة ونشأتها، فان هناك اتفاقا على ارتباط هذه الظاهرة بتوزيع القوة داخل المجتمع الانساني فبعد ان كانت هذه الكلمة )النخبة( تستخدم في القرن السابع عشر لوصف سلع ذات تفوق معين امتد استعمالها فيما بعد ليشمل الاشارة الى فئات اجتماعية متفوقة ك